Merge branch 'master' of github.com:gchq/CyberChef into node-lib

.eslintrc.json

@@ -102,6 +102,7 @@
         "$": false,
         "jQuery": false,
         "log": false,
+        "app": false,
 
         "COMPILE_TIME": false,
         "COMPILE_MSG": false,

.gitignore

@@ -6,6 +6,8 @@ docs/*
 !docs/*.conf.json
 !docs/*.ico
 .vscode
+.*.swp
+.DS_Store
 src/core/config/modules/*
 src/core/config/OperationConfig.json
 src/core/operations/index.mjs

CHANGELOG.md

@@ -2,6 +2,18 @@
 All major and minor version changes will be documented in this file. Details of patch-level version changes can be found in [commit messages](https://github.com/gchq/CyberChef/commits/master).
 
 
+### [8.27.0] - 2019-03-14
+- 'Enigma', 'Typex', 'Bombe' and 'Multiple Bombe' operations added [@s2224834] | [#516]
+- See [this wiki article](https://github.com/gchq/CyberChef/wiki/Enigma,-the-Bombe,-and-Typex) for a full explanation of these operations.
+- New Bombe-style loading animation added for long-running operations [@n1474335]
+- New operation argument types added: `populateMultiOption` and `argSelector` [@n1474335]
+
+### [8.26.0] - 2019-03-09
+- Various image manipulation operations added [@j433866] | [#506]
+
+### [8.25.0] - 2019-03-09
+- 'Extract Files' operation added and more file formats supported [@n1474335] | [#440]
+
 ### [8.24.0] - 2019-02-08
 - 'DNS over HTTPS' operation added [@h345983745] | [#489]
 
@@ -106,6 +118,9 @@ All major and minor version changes will be documented in this file. Details of
 
 
 
+[8.27.0]: https://github.com/gchq/CyberChef/releases/tag/v8.27.0
+[8.26.0]: https://github.com/gchq/CyberChef/releases/tag/v8.26.0
+[8.25.0]: https://github.com/gchq/CyberChef/releases/tag/v8.25.0
 [8.24.0]: https://github.com/gchq/CyberChef/releases/tag/v8.24.0
 [8.23.1]: https://github.com/gchq/CyberChef/releases/tag/v8.23.1
 [8.23.0]: https://github.com/gchq/CyberChef/releases/tag/v8.23.0
@@ -180,6 +195,7 @@ All major and minor version changes will be documented in this file. Details of
 [#394]: https://github.com/gchq/CyberChef/pull/394
 [#428]: https://github.com/gchq/CyberChef/pull/428
 [#439]: https://github.com/gchq/CyberChef/pull/439
+[#440]: https://github.com/gchq/CyberChef/pull/440
 [#441]: https://github.com/gchq/CyberChef/pull/441
 [#443]: https://github.com/gchq/CyberChef/pull/443
 [#446]: https://github.com/gchq/CyberChef/pull/446
@@ -192,3 +208,4 @@ All major and minor version changes will be documented in this file. Details of
 [#468]: https://github.com/gchq/CyberChef/pull/468
 [#476]: https://github.com/gchq/CyberChef/pull/476
 [#489]: https://github.com/gchq/CyberChef/pull/489
+[#506]: https://github.com/gchq/CyberChef/pull/506

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "cyberchef",
-  "version": "8.24.2",
+  "version": "8.27.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -8171,9 +8171,9 @@
       "integrity": "sha1-ZMTwJfF/1Tv7RXY/rrFvAVp0dVA="
     },
     "libyara-wasm": {
-      "version": "0.0.11",
-      "resolved": "https://registry.npmjs.org/libyara-wasm/-/libyara-wasm-0.0.11.tgz",
-      "integrity": "sha512-rglapPFo0IHPNksWYQXI8oqftXYj5mOGOf4BXtbSySVRX71pro4BehNjJ5qEpjYx+roGvNkcAD9zCsitA08sxw=="
+      "version": "0.0.12",
+      "resolved": "https://registry.npmjs.org/libyara-wasm/-/libyara-wasm-0.0.12.tgz",
+      "integrity": "sha512-AjTe4FiBuH4F7HwGT/3UxoRenczXtrbM6oWGrifxb44LrkDh5VxRNg9zwfPpDA5Fcc1iYcXS0WVA/b3DGtD8cQ=="
     },
     "livereload-js": {
       "version": "2.4.0",
@@ -12507,6 +12507,28 @@
       "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-2.0.0.tgz",
       "integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc="
     },
+    "svg-url-loader": {
+      "version": "2.3.2",
+      "resolved": "https://registry.npmjs.org/svg-url-loader/-/svg-url-loader-2.3.2.tgz",
+      "integrity": "sha1-3YaybBn+O5FPBOoQ7zlZTq3gRGQ=",
+      "dev": true,
+      "requires": {
+        "file-loader": "1.1.11",
+        "loader-utils": "1.1.0"
+      },
+      "dependencies": {
+        "file-loader": {
+          "version": "1.1.11",
+          "resolved": "https://registry.npmjs.org/file-loader/-/file-loader-1.1.11.tgz",
+          "integrity": "sha512-TGR4HU7HUsGg6GCOPJnFk06RhWgEWFLAGWiT6rcD+GRC2keU3s9RGJ+b3Z6/U73jwwNb2gKLJ7YCrp+jvU4ALg==",
+          "dev": true,
+          "requires": {
+            "loader-utils": "^1.0.2",
+            "schema-utils": "^0.4.5"
+          }
+        }
+      }
+    },
     "symbol-tree": {
       "version": "3.2.2",
       "resolved": "https://registry.npmjs.org/symbol-tree/-/symbol-tree-3.2.2.tgz",

package.json

@@ -1,6 +1,6 @@
 {
   "name": "cyberchef",
-  "version": "8.24.2",
+  "version": "8.27.0",
   "description": "The Cyber Swiss Army Knife for encryption, encoding, compression and data analysis.",
   "author": "n1474335 <n1474335@gmail.com>",
   "homepage": "https://gchq.github.io/CyberChef",
@@ -71,6 +71,7 @@
     "sitemap": "^2.1.0",
     "style-loader": "^0.23.1",
     "uglifyjs-webpack-plugin": "^2.0.1",
+    "svg-url-loader": "^2.3.2",
     "url-loader": "^1.1.2",
     "web-resource-inliner": "^4.2.1",
     "webpack": "^4.28.3",
@@ -111,7 +112,7 @@
     "jsqr": "^1.1.1",
     "jsrsasign": "8.0.12",
     "kbpgp": "^2.0.82",
-    "libyara-wasm": "0.0.11",
+    "libyara-wasm": "0.0.12",
     "lodash": "^4.17.11",
     "loglevel": "^1.6.1",
     "loglevel-message-prefix": "^3.0.0",

src/core/Chef.mjs

@@ -89,23 +89,26 @@ class Chef {
             progress = err.progress;
         }
 
-        // Depending on the size of the output, we may send it back as a string or an ArrayBuffer.
-        // This can prevent unnecessary casting as an ArrayBuffer can be easily downloaded as a file.
-        // The threshold is specified in KiB.
-        const threshold = (options.ioDisplayThreshold || 1024) * 1024;
-        const returnType = this.dish.size > threshold ? Dish.ARRAY_BUFFER : Dish.STRING;
-
         // Create a raw version of the dish, unpresented
         const rawDish = this.dish.clone();
 
         // Present the raw result
         await recipe.present(this.dish);
 
+        // Depending on the size of the output, we may send it back as a string or an ArrayBuffer.
+        // This can prevent unnecessary casting as an ArrayBuffer can be easily downloaded as a file.
+        // The threshold is specified in KiB.
+        const threshold = (options.ioDisplayThreshold || 1024) * 1024;
+        const returnType =
+            this.dish.size > threshold ?
+                Dish.ARRAY_BUFFER :
+                this.dish.type === Dish.HTML ?
+                    Dish.HTML :
+                    Dish.STRING;
+
         return {
             dish: rawDish,
-            result: this.dish.type === Dish.HTML ?
-                await this.dish.get(Dish.HTML, notUTF8) :
-                await this.dish.get(returnType, notUTF8),
+            result: await this.dish.get(returnType, notUTF8),
             type: Dish.enumLookup(this.dish.type),
             progress: progress,
             duration: new Date().getTime() - startTime,

src/core/Ingredient.mjs

@@ -27,6 +27,9 @@ class Ingredient {
         this.toggleValues = [];
         this.target = null;
         this.defaultIndex = 0;
+        this.min = null;
+        this.max = null;
+        this.step = 1;
 
         if (ingredientConfig) {
             this._parseConfig(ingredientConfig);
@@ -50,6 +53,9 @@ class Ingredient {
         this.toggleValues = ingredientConfig.toggleValues;
         this.target = typeof ingredientConfig.target !== "undefined" ? ingredientConfig.target : null;
         this.defaultIndex = typeof ingredientConfig.defaultIndex !== "undefined" ? ingredientConfig.defaultIndex : 0;
+        this.min = ingredientConfig.min;
+        this.max = ingredientConfig.max;
+        this.step = ingredientConfig.step;
     }
 
 

src/core/Operation.mjs

@@ -184,6 +184,9 @@ class Operation {
             if (ing.disabled) conf.disabled = ing.disabled;
             if (ing.target) conf.target = ing.target;
             if (ing.defaultIndex) conf.defaultIndex = ing.defaultIndex;
+            if (typeof ing.min === "number") conf.min = ing.min;
+            if (typeof ing.max === "number") conf.max = ing.max;
+            if (ing.step) conf.step = ing.step;
             return conf;
         });
     }

src/core/Utils.mjs

@@ -830,8 +830,9 @@ class Utils {
             const buff = await Utils.readFile(file);
             const blob = new Blob(
                 [buff],
-                {type: "octet/stream"}
+                {type: file.type || "octet/stream"}
             );
+            const blobURL = URL.createObjectURL(blob);
 
             const html = `<div class='card' style='white-space: normal;'>
                     <div class='card-header' id='heading${i}'>
@@ -846,10 +847,19 @@ class Utils {
                             <span class='float-right' style="margin-top: -3px">
                                 ${file.size.toLocaleString()} bytes
                                 <a title="Download ${Utils.escapeHtml(file.name)}"
-                                    href='${URL.createObjectURL(blob)}'
-                                    download='${Utils.escapeHtml(file.name)}'>
+                                    href="${blobURL}"
+                                    download="${Utils.escapeHtml(file.name)}"
+                                    data-toggle="tooltip">
                                     <i class="material-icons" style="vertical-align: bottom">save</i>
                                 </a>
+                                <a title="Move to input"
+                                    href="#"
+                                    blob-url="${blobURL}"
+                                    file-name="${Utils.escapeHtml(file.name)}"
+                                    class="extract-file"
+                                    data-toggle="tooltip">
+                                    <i class="material-icons" style="vertical-align: bottom">open_in_browser</i>
+                                </a>
                             </span>
                         </h6>
                     </div>
@@ -1187,6 +1197,21 @@ String.prototype.count = function(chr) {
 };
 
 
+/**
+ * Wrapper for self.sendStatusMessage to handle different environments.
+ *
+ * @param {string} msg
+ */
+export function sendStatusMessage(msg) {
+    if (ENVIRONMENT_IS_WORKER())
+        self.sendStatusMessage(msg);
+    else if (ENVIRONMENT_IS_WEB())
+        app.alert(msg, 10000);
+    else if (ENVIRONMENT_IS_NODE())
+        log.debug(msg);
+}
+
+
 /*
  * Polyfills
  */

src/core/config/Categories.json

@@ -102,7 +102,11 @@
             "JWT Decode",
             "Citrix CTX1 Encode",
             "Citrix CTX1 Decode",
-            "Pseudo-Random Number Generator"
+            "Pseudo-Random Number Generator",
+            "Enigma",
+            "Bombe",
+            "Multiple Bombe",
+            "Typex"
         ]
     },
     {
@@ -254,7 +258,8 @@
             "XPath expression",
             "JPath expression",
             "CSS selector",
-            "Extract EXIF"
+            "Extract EXIF",
+            "Extract Files"
         ]
     },
     {
@@ -348,6 +353,7 @@
         "ops": [
             "Detect File Type",
             "Scan for Embedded Files",
+            "Extract Files",
             "Remove EXIF",
             "Extract EXIF"
         ]
@@ -359,7 +365,20 @@
             "Play Media",
             "Remove EXIF",
             "Extract EXIF",
-            "Split Colour Channels"
+            "Split Colour Channels",
+            "Rotate Image",
+            "Resize Image",
+            "Blur Image",
+            "Dither Image",
+            "Invert Image",
+            "Flip Image",
+            "Crop Image",
+            "Image Brightness / Contrast",
+            "Image Opacity",
+            "Image Filter",
+            "Contain Image",
+            "Cover Image",
+            "Image Hue/Saturation/Lightness"
         ]
     },
     {

src/core/lib/BCD.mjs

@@ -0,0 +1,756 @@
+/**
+ * Emulation of the Bombe machine.
+ *
+ * @author s2224834
+ * @author The National Museum of Computing - Bombe Rebuild Project
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import OperationError from "../errors/OperationError";
+import Utils from "../Utils";
+import {Rotor, Plugboard, a2i, i2a} from "./Enigma";
+
+/**
+ * Convenience/optimisation subclass of Rotor
+ *
+ * This allows creating multiple Rotors which share backing maps, to avoid repeatedly parsing the
+ * rotor spec strings and duplicating the maps in memory.
+ */
+class CopyRotor extends Rotor {
+    /**
+     * Return a copy of this Rotor.
+     * @returns {Object}
+     */
+    copy() {
+        const clone = {
+            map: this.map,
+            revMap: this.revMap,
+            pos: this.pos,
+            step: this.step,
+            transform: this.transform,
+            revTransform: this.revTransform,
+        };
+        return clone;
+    }
+}
+
+/**
+ * Node in the menu graph
+ *
+ * A node represents a cipher/plaintext letter.
+ */
+class Node {
+    /**
+     * Node constructor.
+     * @param {number} letter - The plain/ciphertext letter this node represents (as a number).
+     */
+    constructor(letter) {
+        this.letter = letter;
+        this.edges = new Set();
+        this.visited = false;
+    }
+}
+
+/**
+ * Edge in the menu graph
+ *
+ * An edge represents an Enigma machine transformation between two letters.
+ */
+class Edge {
+    /**
+     * Edge constructor - an Enigma machine mapping between letters
+     * @param {number} pos - The rotor position, relative to the beginning of the crib, at this edge
+     * @param {number} node1 - Letter at one end (as a number)
+     * @param {number} node2 - Letter at the other end
+     */
+    constructor(pos, node1, node2) {
+        this.pos = pos;
+        this.node1 = node1;
+        this.node2 = node2;
+        node1.edges.add(this);
+        node2.edges.add(this);
+        this.visited = false;
+    }
+
+    /**
+     * Given the node at one end of this edge, return the other end.
+     * @param node {number} - The node we have
+     * @returns {number}
+     */
+    getOther(node) {
+        return this.node1 === node ? this.node2 : this.node1;
+    }
+}
+
+/**
+ * As all the Bombe's rotors move in step, at any given point the vast majority of the scramblers
+ * in the machine share the majority of their state, which is hosted in this class.
+ */
+class SharedScrambler {
+    /**
+     * SharedScrambler constructor.
+     * @param {Object[]} rotors - List of rotors in the shared state _only_.
+     * @param {Object} reflector - The reflector in use.
+     */
+    constructor(rotors, reflector) {
+        this.lowerCache = new Array(26);
+        this.higherCache = new Array(26);
+        for (let i=0; i<26; i++) {
+            this.higherCache[i] = new Array(26);
+        }
+        this.changeRotors(rotors, reflector);
+    }
+
+    /**
+     * Replace the rotors and reflector in this SharedScrambler.
+     * This takes care of flushing caches as well.
+     * @param {Object[]} rotors - List of rotors in the shared state _only_.
+     * @param {Object} reflector - The reflector in use.
+     */
+    changeRotors(rotors, reflector) {
+        this.reflector = reflector;
+        this.rotors = rotors;
+        this.rotorsRev = [].concat(rotors).reverse();
+        this.cacheGen();
+    }
+
+    /**
+     * Step the rotors forward.
+     * @param {number} n - How many rotors to step. This includes the rotors which are not part of
+     * the shared state, so should be 2 or more.
+     */
+    step(n) {
+        for (let i=0; i<n-1; i++) {
+            this.rotors[i].step();
+        }
+        this.cacheGen();
+    }
+
+    /**
+     * Optimisation: We pregenerate all routes through the machine with the top rotor removed,
+     * as these rarely change. This saves a lot of lookups. This function generates this route
+     * table.
+     * We also just-in-time cache the full routes through the scramblers, because after stepping
+     * the fast rotor some scramblers will be in states occupied by other scrambles on previous
+     * iterations.
+     */
+    cacheGen() {
+        for (let i=0; i<26; i++) {
+            this.lowerCache[i] = undefined;
+            for (let j=0; j<26; j++) {
+                this.higherCache[i][j] = undefined;
+            }
+        }
+        for (let i=0; i<26; i++) {
+            if (this.lowerCache[i] !== undefined) {
+                continue;
+            }
+            let letter = i;
+            for (const rotor of this.rotors) {
+                letter = rotor.transform(letter);
+            }
+            letter = this.reflector.transform(letter);
+            for (const rotor of this.rotorsRev) {
+                letter = rotor.revTransform(letter);
+            }
+            // By symmetry
+            this.lowerCache[i] = letter;
+            this.lowerCache[letter] = i;
+        }
+    }
+
+    /**
+     * Map a letter through this (partial) scrambler.
+     * @param {number} i - The letter
+     * @returns {number}
+     */
+    transform(i) {
+        return this.lowerCache[i];
+    }
+}
+
+/**
+ * Scrambler.
+ *
+ * This is effectively just an Enigma machine, but it only operates on one character at a time and
+ * the stepping mechanism is different.
+ */
+class Scrambler {
+    /** Scrambler constructor.
+     * @param {Object} base - The SharedScrambler whose state this scrambler uses
+     * @param {Object} rotor - The non-shared fast rotor in this scrambler
+     * @param {number} pos - Position offset from start of crib
+     * @param {number} end1 - Letter in menu this scrambler is attached to
+     * @param {number} end2 - Other letter in menu this scrambler is attached to
+     */
+    constructor(base, rotor, pos, end1, end2) {
+        this.baseScrambler = base;
+        this.initialPos = pos;
+        this.changeRotor(rotor);
+        this.end1 = end1;
+        this.end2 = end2;
+        // For efficiency reasons, we pull the relevant shared cache from the baseScrambler into
+        // this object - this saves us a few pointer dereferences
+        this.cache = this.baseScrambler.higherCache[pos];
+    }
+
+    /**
+     * Replace the rotor in this scrambler.
+     * The position is reset automatically.
+     * @param {Object} rotor - New rotor
+     */
+    changeRotor(rotor) {
+        this.rotor = rotor;
+        this.rotor.pos += this.initialPos;
+    }
+
+    /**
+     * Step the rotor forward.
+     *
+     * The base SharedScrambler needs to be instructed to step separately.
+     */
+    step() {
+        // The Bombe steps the slowest rotor on an actual Enigma fastest, for reasons.
+        // ...but for optimisation reasons I'm going to cheat and not do that, as this vastly
+        // simplifies caching the state of the majority of the scramblers. The results are the
+        // same, just in a slightly different order.
+        this.rotor.step();
+        this.cache = this.baseScrambler.higherCache[this.rotor.pos];
+    }
+
+
+    /**
+     * Run a letter through the scrambler.
+     * @param {number} i - The letter to transform (as a number)
+     * @returns {number}
+     */
+    transform(i) {
+        let letter = i;
+        const cached = this.cache[i];
+        if (cached !== undefined) {
+            return cached;
+        }
+        letter = this.rotor.transform(letter);
+        letter = this.baseScrambler.transform(letter);
+        letter = this.rotor.revTransform(letter);
+        this.cache[i] = letter;
+        this.cache[letter] = i;
+        return letter;
+    }
+
+    /**
+     * Given one letter in the menu this scrambler maps to, return the other.
+     * @param end {number} - The node we have
+     * @returns {number}
+     */
+    getOtherEnd(end) {
+        return this.end1 === end ? this.end2 : this.end1;
+    }
+
+    /**
+     * Read the position this scrambler is set to.
+     * Note that because of Enigma's stepping, you need to set an actual Enigma to the previous
+     * position in order to get it to make a certain set of electrical connections when a button
+     * is pressed - this function *does* take this into account.
+     * However, as with the rest of the Bombe, it does not take stepping into account - the middle
+     * and slow rotors are treated as static.
+     * @return {string}
+     */
+    getPos() {
+        let result = "";
+        // Roll back the fast rotor by one step
+        let pos = Utils.mod(this.rotor.pos - 1, 26);
+        result += i2a(pos);
+        for (let i=0; i<this.baseScrambler.rotors.length; i++) {
+            pos = this.baseScrambler.rotors[i].pos;
+            result += i2a(pos);
+        }
+        return result.split("").reverse().join("");
+    }
+}
+
+/**
+ * Bombe simulator class.
+ */
+export class BombeMachine {
+    /**
+     * Construct a Bombe.
+     *
+     * Note that there is no handling of offsets here: the crib specified must exactly match the
+     * ciphertext. It will check that the crib is sane (length is vaguely sensible and there's no
+     * matching characters between crib and ciphertext) but cannot check further - if it's wrong
+     * your results will be wrong!
+     *
+     * There is also no handling of rotor stepping - if the target Enigma stepped in the middle of
+     * your crib, you're out of luck. TODO: Allow specifying a step point - this is fairly easy to
+     * configure on a real Bombe, but we're not clear on whether it was ever actually done for
+     * real (there would almost certainly have been better ways of attacking in most situations
+     * than attempting to exhaust options for the stepping point, but in some circumstances, e.g.
+     * via Banburismus, the stepping point might have been known).
+     *
+     * @param {string[]} rotors - list of rotor spec strings (without step points!)
+     * @param {Object} reflector - Reflector object
+     * @param {string} ciphertext - The ciphertext to attack
+     * @param {string} crib - Known plaintext for this ciphertext
+     * @param {boolean} check - Whether to use the checking machine
+     * @param {function} update - Function to call to send status updates (optional)
+     */
+    constructor(rotors, reflector, ciphertext, crib, check, update=undefined) {
+        if (ciphertext.length < crib.length) {
+            throw new OperationError("Crib overruns supplied ciphertext");
+        }
+        if (crib.length < 2) {
+            // This is the absolute bare minimum to be sane, and even then it's likely too short to
+            // be useful
+            throw new OperationError("Crib is too short");
+        }
+        if (crib.length > 25) {
+            // A crib longer than this will definitely cause the middle rotor to step somewhere
+            // A shorter crib is preferable to reduce this chance, of course
+            throw new OperationError("Crib is too long");
+        }
+        for (let i=0; i<crib.length; i++) {
+            if (ciphertext[i] === crib[i]) {
+                throw new OperationError(`Invalid crib: character ${ciphertext[i]} at pos ${i} in both ciphertext and crib`);
+            }
+        }
+        this.ciphertext = ciphertext;
+        this.crib = crib;
+        this.initRotors(rotors);
+        this.check = check;
+        this.updateFn = update;
+
+        const [mostConnected, edges] = this.makeMenu();
+
+        // This is the bundle of wires corresponding to the 26 letters within each of the 26
+        // possible nodes in the menu
+        this.wires = new Array(26*26);
+
+        // These are the pseudo-Engima devices corresponding to each edge in the menu, and the
+        // nodes in the menu they each connect to
+        this.scramblers = new Array();
+        for (let i=0; i<26; i++) {
+            this.scramblers.push(new Array());
+        }
+        this.sharedScrambler = new SharedScrambler(this.baseRotors.slice(1), reflector);
+        this.allScramblers = new Array();
+        this.indicator = undefined;
+        for (const edge of edges) {
+            const cRotor = this.baseRotors[0].copy();
+            const end1 = a2i(edge.node1.letter);
+            const end2 = a2i(edge.node2.letter);
+            const scrambler = new Scrambler(this.sharedScrambler, cRotor, edge.pos, end1, end2);
+            if (edge.pos === 0) {
+                this.indicator = scrambler;
+            }
+            this.scramblers[end1].push(scrambler);
+            this.scramblers[end2].push(scrambler);
+            this.allScramblers.push(scrambler);
+        }
+        // The Bombe uses a set of rotors to keep track of what settings it's testing. We cheat and
+        // use one of the actual scramblers if there's one in the right position, but if not we'll
+        // just create one.
+        if (this.indicator === undefined) {
+            this.indicator = new Scrambler(this.sharedScrambler, this.baseRotors[0].copy(), 0, undefined, undefined);
+            this.allScramblers.push(this.indicator);
+        }
+
+        this.testRegister = a2i(mostConnected.letter);
+        // This is an arbitrary letter other than the most connected letter
+        for (const edge of mostConnected.edges) {
+            this.testInput = [this.testRegister, a2i(edge.getOther(mostConnected).letter)];
+            break;
+        }
+    }
+
+    /**
+     * Build Rotor objects from list of rotor wiring strings.
+     * @param {string[]} rotors - List of rotor wiring strings
+     */
+    initRotors(rotors) {
+        // This is ordered from the Enigma fast rotor to the slow, so bottom to top for the Bombe
+        this.baseRotors = [];
+        for (const rstr of rotors) {
+            const rotor = new CopyRotor(rstr, "", "A", "A");
+            this.baseRotors.push(rotor);
+        }
+    }
+
+    /**
+     * Replace the rotors and reflector in all components of this Bombe.
+     * @param {string[]} rotors - List of rotor wiring strings
+     * @param {Object} reflector - Reflector object
+     */
+    changeRotors(rotors, reflector) {
+        // At the end of the run, the rotors are all back in the same position they started
+        this.initRotors(rotors);
+        this.sharedScrambler.changeRotors(this.baseRotors.slice(1), reflector);
+        for (const scrambler of this.allScramblers) {
+            scrambler.changeRotor(this.baseRotors[0].copy());
+        }
+    }
+
+    /**
+     * If we have a way of sending status messages, do so.
+     * @param {...*} msg - Message to send.
+     */
+    update(...msg) {
+        if (this.updateFn !== undefined) {
+            this.updateFn(...msg);
+        }
+    }
+
+    /**
+     * Recursive depth-first search on the menu graph.
+     * This is used to a) isolate unconnected sub-graphs, and b) count the number of loops in each
+     * of those graphs.
+     * @param {Object} node - Node object to start the search from
+     * @returns {[number, number, Object, number, Object[]} - loop count, node count, most connected
+     *      node, order of most connected node, list of edges in this sub-graph
+     */
+    dfs(node) {
+        let loops = 0;
+        let nNodes = 1;
+        let mostConnected = node;
+        let nConnections = mostConnected.edges.size;
+        let edges = new Set();
+        node.visited = true;
+        for (const edge of node.edges) {
+            if (edge.visited) {
+                // Already been here from the other end.
+                continue;
+            }
+            edge.visited = true;
+            edges.add(edge);
+            const other = edge.getOther(node);
+            if (other.visited) {
+                // We have a loop, record that and continue
+                loops += 1;
+                continue;
+            }
+            // This is a newly visited node
+            const [oLoops, oNNodes, oMostConnected, oNConnections, oEdges] = this.dfs(other);
+            loops += oLoops;
+            nNodes += oNNodes;
+            edges = new Set([...edges, ...oEdges]);
+            if (oNConnections > nConnections) {
+                mostConnected = oMostConnected;
+                nConnections = oNConnections;
+            }
+        }
+        return [loops, nNodes, mostConnected, nConnections, edges];
+    }
+
+    /**
+     * Build a menu from the ciphertext and crib.
+     * A menu is just a graph where letters in either the ciphertext or crib (Enigma is symmetric,
+     * so there's no difference mathematically) are nodes and states of the Enigma machine itself
+     * are the edges.
+     * Additionally, we want a single connected graph, and of the subgraphs available, we want the
+     * one with the most loops (since these generate feedback cycles which efficiently close off
+     * disallowed states).
+     * Finally, we want to identify the most connected node in that graph (as it's the best choice
+     * of measurement point).
+     * @returns [Object, Object[]] - the most connected node, and the list of edges in the subgraph
+     */
+    makeMenu() {
+        // First, we make a graph of all of the mappings given by the crib
+        // Make all nodes first
+        const nodes = new Map();
+        for (const c of this.ciphertext + this.crib) {
+            if (!nodes.has(c)) {
+                const node = new Node(c);
+                nodes.set(c, node);
+            }
+        }
+        // Then all edges
+        for (let i=0; i<this.crib.length; i++) {
+            const a = this.crib[i];
+            const b = this.ciphertext[i];
+            new Edge(i, nodes.get(a), nodes.get(b));
+        }
+        // list of [loop_count, node_count, most_connected_node, connections_on_most_connected, edges]
+        const graphs = [];
+        // Then, for each unconnected subgraph, we count the number of loops and nodes
+        for (const start of nodes.keys()) {
+            if (nodes.get(start).visited) {
+                continue;
+            }
+            const subgraph = this.dfs(nodes.get(start));
+            graphs.push(subgraph);
+        }
+        // Return the subgraph with the most loops (ties broken by node count)
+        graphs.sort((a, b) => {
+            let result = b[0] - a[0];
+            if (result === 0) {
+                result = b[1] - a[1];
+            }
+            return result;
+        });
+        this.nLoops = graphs[0][0];
+        return [graphs[0][2], graphs[0][4]];
+    }
+
+    /**
+     * Bombe electrical simulation. Energise a wire. For all connected wires (both via the diagonal
+     * board and via the scramblers), energise them too, recursively.
+     * @param {number} i - Bombe wire bundle
+     * @param {number} j - Bombe stecker hypothesis wire within bundle
+     */
+    energise(i, j) {
+        const idx = 26*i + j;
+        if (this.wires[idx]) {
+            return;
+        }
+        this.wires[idx] = true;
+        // Welchman's diagonal board: if A steckers to B, that implies B steckers to A. Handle
+        // both.
+        const idxPair = 26*j + i;
+        this.wires[idxPair] = true;
+        if (i === this.testRegister || j === this.testRegister) {
+            this.energiseCount++;
+            if (this.energiseCount === 26) {
+                // no point continuing, bail out
+                return;
+            }
+        }
+
+        for (let k=0; k<this.scramblers[i].length; k++) {
+            const scrambler = this.scramblers[i][k];
+            const out = scrambler.transform(j);
+            const other = scrambler.getOtherEnd(i);
+            // Lift the pre-check before the call, to save some function call overhead
+            const otherIdx = 26*other + out;
+            if (!this.wires[otherIdx]) {
+                this.energise(other, out);
+                if (this.energiseCount === 26) {
+                    return;
+                }
+            }
+        }
+        if (i === j) {
+            return;
+        }
+        for (let k=0; k<this.scramblers[j].length; k++) {
+            const scrambler = this.scramblers[j][k];
+            const out = scrambler.transform(i);
+            const other = scrambler.getOtherEnd(j);
+            const otherIdx = 26*other + out;
+            if (!this.wires[otherIdx]) {
+                this.energise(other, out);
+                if (this.energiseCount === 26) {
+                    return;
+                }
+            }
+        }
+    }
+
+    /**
+     * Trial decryption at the current setting.
+     * Used after we get a stop.
+     * This applies the detected stecker pair if we have one. It does not handle the other
+     * steckering or stepping (which is why we limit it to 26 characters, since it's guaranteed to
+     * be wrong after that anyway).
+     * @param {string} stecker - Known stecker spec string.
+     * @returns {string}
+     */
+    tryDecrypt(stecker) {
+        const fastRotor = this.indicator.rotor;
+        const initialPos = fastRotor.pos;
+        const res = [];
+        const plugboard = new Plugboard(stecker);
+        // The indicator scrambler starts in the right place for the beginning of the ciphertext.
+        for (let i=0; i<Math.min(26, this.ciphertext.length); i++) {
+            const t = this.indicator.transform(plugboard.transform(a2i(this.ciphertext[i])));
+            res.push(i2a(plugboard.transform(t)));
+            this.indicator.step(1);
+        }
+        fastRotor.pos = initialPos;
+        return res.join("");
+    }
+
+    /**
+     * Format a steckered pair, in sorted order to allow uniquing.
+     * @param {number} a - A letter
+     * @param {number} b - Its stecker pair
+     * @returns {string}
+     */
+    formatPair(a, b) {
+        if (a < b) {
+            return `${i2a(a)}${i2a(b)}`;
+        }
+        return `${i2a(b)}${i2a(a)}`;
+    }
+
+    /**
+     * The checking machine was used to manually verify Bombe stops. Using a device which was
+     * effectively a non-stepping Enigma, the user would walk through each of the links in the
+     * menu at the rotor positions determined by the Bombe. By starting with the stecker pair the
+     * Bombe gives us, we find the stecker pair of each connected letter in the graph, and so on.
+     * If a contradiction is reached, the stop is invalid. If not, we have most (but not
+     * necessarily all) of the plugboard connections.
+     * You will notice that this procedure is exactly the same as what the Bombe itself does, only
+     * we start with an assumed good hypothesis and read out the stecker pair for every letter.
+     * On the real hardware that wasn't practical, but fortunately we're not the real hardware, so
+     * we don't need to implement the manual checking machine procedure.
+     * @param {number} pair - The stecker pair of the test register.
+     * @returns {string} - The empty string for invalid stops, or a plugboard configuration string
+     *      containing all known pairs.
+     */
+    checkingMachine(pair) {
+        if (pair !== this.testInput[1]) {
+            // We have a new hypothesis for this stop - apply the new one.
+            // De-energise the board
+            for (let i=0; i<this.wires.length; i++) {
+                this.wires[i] = false;
+            }
+            this.energiseCount = 0;
+            // Re-energise with the corrected hypothesis
+            this.energise(this.testRegister, pair);
+        }
+
+        const results = new Set();
+        results.add(this.formatPair(this.testRegister, pair));
+        for (let i=0; i<26; i++) {
+            let count = 0;
+            let other;
+            for (let j=0; j<26; j++) {
+                if (this.wires[i*26 + j]) {
+                    count++;
+                    other = j;
+                }
+            }
+            if (count > 1) {
+                // This is an invalid stop.
+                return "";
+            } else if (count === 0) {
+                // No information about steckering from this wire
+                continue;
+            }
+            results.add(this.formatPair(i, other));
+        }
+        return [...results].join(" ");
+    }
+
+    /**
+     * Check to see if the Bombe has stopped. If so, process the stop.
+     * @returns {(undefined|string[3])} - Undefined for no stop, or [rotor settings, plugboard settings, decryption preview]
+     */
+    checkStop() {
+        // Count the energised outputs
+        const count = this.energiseCount;
+        if (count === 26) {
+            return undefined;
+        }
+        // If it's not all of them, we have a stop
+        let steckerPair;
+        // The Bombe tells us one stecker pair as well. The input wire and test register we
+        // started with are hypothesised to be a stecker pair.
+        if (count === 25) {
+            // Our steckering hypothesis is wrong. Correct value is the un-energised wire.
+            for (let j=0; j<26; j++) {
+                if (!this.wires[26*this.testRegister + j]) {
+                    steckerPair = j;
+                    break;
+                }
+            }
+        } else if (count === 1) {
+            // This means our hypothesis for the steckering is correct.
+            steckerPair = this.testInput[1];
+        } else {
+            // This was known as a "boxing stop" - we have a stop but not a single hypothesis.
+            // If this happens a lot it implies the menu isn't good enough.
+            // If we have the checking machine enabled, we're going to just check each wire in
+            // turn. If we get 0 or 1 hit, great.
+            // If we get multiple hits, or the checking machine is off, the user will just have to
+            // deal with it.
+            if (!this.check) {
+                // We can't draw any conclusions about the steckering (one could maybe suggest
+                // options in some cases, but too hard to present clearly).
+                return [this.indicator.getPos(), "??", this.tryDecrypt("")];
+            }
+            let stecker = undefined;
+            for (let i = 0; i < 26; i++) {
+                const newStecker = this.checkingMachine(i);
+                if (newStecker !== "") {
+                    if (stecker !== undefined) {
+                        // Multiple hypotheses can't be ruled out.
+                        return [this.indicator.getPos(), "??", this.tryDecrypt("")];
+                    }
+                    stecker = newStecker;
+                }
+            }
+            if (stecker === undefined) {
+                // Checking machine ruled all possibilities out.
+                return undefined;
+            }
+            // If we got here, there was just one possibility allowed by the checking machine. Success.
+            return [this.indicator.getPos(), stecker, this.tryDecrypt(stecker)];
+        }
+        let stecker;
+        if (this.check) {
+            stecker = this.checkingMachine(steckerPair);
+            if (stecker === "") {
+                // Invalid stop - don't count it, don't return it
+                return undefined;
+            }
+        } else {
+            stecker = `${i2a(this.testRegister)}${i2a(steckerPair)}`;
+        }
+        const testDecrypt = this.tryDecrypt(stecker);
+        return [this.indicator.getPos(), stecker, testDecrypt];
+    }
+
+    /**
+     * Having set up the Bombe, do the actual attack run. This tries every possible rotor setting
+     * and attempts to logically invalidate them. If it can't, it's added to the list of candidate
+     * solutions.
+     * @returns {string[][3]} - list of 3-tuples of candidate rotor setting, plugboard settings, and decryption preview
+     */
+    run() {
+        let stops = 0;
+        const result = [];
+        // For each possible rotor setting
+        const nChecks = Math.pow(26, this.baseRotors.length);
+        for (let i=1; i<=nChecks; i++) {
+            // Benchmarking suggests this is faster than using .fill()
+            for (let i=0; i<this.wires.length; i++) {
+                this.wires[i] = false;
+            }
+            this.energiseCount = 0;
+            // Energise the test input, follow the current through each scrambler
+            // (and the diagonal board)
+            this.energise(...this.testInput);
+
+            const stop = this.checkStop();
+            if (stop !== undefined) {
+                stops++;
+                result.push(stop);
+            }
+            // Step all the scramblers
+            // This loop counts how many rotors have reached their starting position (meaning the
+            // next one needs to step as well)
+            let n = 1;
+            for (let j=1; j<this.baseRotors.length; j++) {
+                if ((i % Math.pow(26, j)) === 0) {
+                    n++;
+                } else {
+                    break;
+                }
+            }
+            if (n > 1) {
+                this.sharedScrambler.step(n);
+            }
+            for (const scrambler of this.allScramblers) {
+                scrambler.step();
+            }
+            // Send status messages at what seems to be a reasonably sensible frequency
+            // (note this won't be triggered on 3-rotor runs - they run fast enough it doesn't seem necessary)
+            if (n > 3) {
+                this.update(this.nLoops, stops, i/nChecks);
+            }
+        }
+        return result;
+    }
+}

src/core/lib/CanvasComponents.mjs

@@ -0,0 +1,369 @@
+/**
+ * Emulation of the Enigma machine.
+ *
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import OperationError from "../errors/OperationError";
+import Utils from "../Utils";
+
+/**
+ * Provided default Enigma rotor set.
+ * These are specified as a list of mappings from the letters A through Z in order, optionally
+ * followed by < and a list of letters at which the rotor steps.
+ */
+export const ROTORS = [
+    {name: "I", value: "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R"},
+    {name: "II", value: "AJDKSIRUXBLHWTMCQGZNPYFVOE<F"},
+    {name: "III", value: "BDFHJLCPRTXVZNYEIWGAKMUSQO<W"},
+    {name: "IV", value: "ESOVPZJAYQUIRHXLNFTGKDCMWB<K"},
+    {name: "V", value: "VZBRGITYUPSDNHLXAWMJQOFECK<A"},
+    {name: "VI", value: "JPGVOUMFYQBENHZRDKASXLICTW<AN"},
+    {name: "VII", value: "NZJHGRCXMYSWBOUFAIVLPEKQDT<AN"},
+    {name: "VIII", value: "FKQHTLXOCBJSPDZRAMEWNIUYGV<AN"},
+];
+
+export const ROTORS_FOURTH = [
+    {name: "Beta", value: "LEYJVCNIXWPBQMDRTAKZGFUHOS"},
+    {name: "Gamma", value: "FSOKANUERHMBTIYCWLQPZXVGJD"},
+];
+
+/**
+ * Provided default Enigma reflector set.
+ * These are specified as 13 space-separated transposed pairs covering every letter.
+ */
+export const REFLECTORS = [
+    {name: "B", value: "AY BR CU DH EQ FS GL IP JX KN MO TZ VW"},
+    {name: "C", value: "AF BV CP DJ EI GO HY KR LZ MX NW TQ SU"},
+    {name: "B Thin", value: "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV"},
+    {name: "C Thin", value: "AR BD CO EJ FN GT HK IV LM PW QZ SX UY"},
+];
+
+export const LETTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".split("");
+
+/**
+ * Map a letter to a number in 0..25.
+ *
+ * @param {char} c
+ * @param {boolean} permissive - Case insensitive; don't throw errors on other chars.
+ * @returns {number}
+ */
+export function a2i(c, permissive=false) {
+    const i = Utils.ord(c);
+    if (i >= 65 && i <= 90) {
+        return i - 65;
+    }
+    if (permissive) {
+        // Allow case insensitivity
+        if (i >= 97 && i <= 122) {
+            return i - 97;
+        }
+        return -1;
+    }
+    throw new OperationError("a2i called on non-uppercase ASCII character");
+}
+
+/**
+ * Map a number in 0..25 to a letter.
+ *
+ * @param {number} i
+ * @returns {char}
+ */
+export function i2a(i) {
+    if (i >= 0 && i < 26) {
+        return Utils.chr(i+65);
+    }
+    throw new OperationError("i2a called on value outside 0..25");
+}
+
+/**
+ * A rotor in the Enigma machine.
+ */
+export class Rotor {
+    /**
+     * Rotor constructor.
+     *
+     * @param {string} wiring - A 26 character string of the wiring order.
+     * @param {string} steps - A 0..26 character string of stepping points.
+     * @param {char} ringSetting - The ring setting.
+     * @param {char} initialPosition - The initial position of the rotor.
+     */
+    constructor(wiring, steps, ringSetting, initialPosition) {
+        if (!/^[A-Z]{26}$/.test(wiring)) {
+            throw new OperationError("Rotor wiring must be 26 unique uppercase letters");
+        }
+        if (!/^[A-Z]{0,26}$/.test(steps)) {
+            throw new OperationError("Rotor steps must be 0-26 unique uppercase letters");
+        }
+        if (!/^[A-Z]$/.test(ringSetting)) {
+            throw new OperationError("Rotor ring setting must be exactly one uppercase letter");
+        }
+        if (!/^[A-Z]$/.test(initialPosition)) {
+            throw new OperationError("Rotor initial position must be exactly one uppercase letter");
+        }
+        this.map = new Array(26);
+        this.revMap = new Array(26);
+        const uniq = {};
+        for (let i=0; i<LETTERS.length; i++) {
+            const a = a2i(LETTERS[i]);
+            const b = a2i(wiring[i]);
+            this.map[a] = b;
+            this.revMap[b] = a;
+            uniq[b] = true;
+        }
+        if (Object.keys(uniq).length !== LETTERS.length) {
+            throw new OperationError("Rotor wiring must have each letter exactly once");
+        }
+        const rs = a2i(ringSetting);
+        this.steps = new Set();
+        for (const x of steps) {
+            this.steps.add(Utils.mod(a2i(x) - rs, 26));
+        }
+        if (this.steps.size !== steps.length) {
+            // This isn't strictly fatal, but it's probably a mistake
+            throw new OperationError("Rotor steps must be unique");
+        }
+        this.pos = Utils.mod(a2i(initialPosition) - rs, 26);
+    }
+
+    /**
+     * Step the rotor forward by one.
+     */
+    step() {
+        this.pos = Utils.mod(this.pos + 1, 26);
+        return this.pos;
+    }
+
+    /**
+     * Transform a character through this rotor forwards.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    transform(c) {
+        return Utils.mod(this.map[Utils.mod(c + this.pos, 26)] - this.pos, 26);
+    }
+
+    /**
+     * Transform a character through this rotor backwards.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    revTransform(c) {
+        return Utils.mod(this.revMap[Utils.mod(c + this.pos, 26)] - this.pos, 26);
+    }
+}
+
+/**
+ * Base class for plugboard and reflector (since these do effectively the same
+ * thing).
+ */
+class PairMapBase {
+    /**
+     * PairMapBase constructor.
+     *
+     * @param {string} pairs - A whitespace separated string of letter pairs to swap.
+     * @param {string} [name='PairMapBase'] - For errors, the name of this object.
+     */
+    constructor(pairs, name="PairMapBase") {
+        // I've chosen to make whitespace significant here to make a) code and
+        // b) inputs easier to read
+        this.pairs = pairs;
+        this.map = {};
+        if (pairs === "") {
+            return;
+        }
+        pairs.split(/\s+/).forEach(pair => {
+            if (!/^[A-Z]{2}$/.test(pair)) {
+                throw new OperationError(name + " must be a whitespace-separated list of uppercase letter pairs");
+            }
+            const a = a2i(pair[0]), b = a2i(pair[1]);
+            if (a === b) {
+                // self-stecker
+                return;
+            }
+            if (this.map.hasOwnProperty(a)) {
+                throw new OperationError(`${name} connects ${pair[0]} more than once`);
+            }
+            if (this.map.hasOwnProperty(b)) {
+                throw new OperationError(`${name} connects ${pair[1]} more than once`);
+            }
+            this.map[a] = b;
+            this.map[b] = a;
+        });
+    }
+
+    /**
+     * Transform a character through this object.
+     * Returns other characters unchanged.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    transform(c) {
+        if (!this.map.hasOwnProperty(c)) {
+            return c;
+        }
+        return this.map[c];
+    }
+
+    /**
+     * Alias for transform, to allow interchangeable use with rotors.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    revTransform(c) {
+        return this.transform(c);
+    }
+}
+
+/**
+ * Reflector. PairMapBase but requires that all characters are accounted for.
+ *
+ * Includes a couple of optimisations on that basis.
+ */
+export class Reflector extends PairMapBase {
+    /**
+     * Reflector constructor. See PairMapBase.
+     * Additional restriction: every character must be accounted for.
+     */
+    constructor(pairs) {
+        super(pairs, "Reflector");
+        const s = Object.keys(this.map).length;
+        if (s !== 26) {
+            throw new OperationError("Reflector must have exactly 13 pairs covering every letter");
+        }
+        const optMap = new Array(26);
+        for (const x of Object.keys(this.map)) {
+            optMap[x] = this.map[x];
+        }
+        this.map = optMap;
+    }
+
+    /**
+     * Transform a character through this object.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    transform(c) {
+        return this.map[c];
+    }
+}
+
+/**
+ * Plugboard. Unmodified PairMapBase.
+ */
+export class Plugboard extends PairMapBase {
+    /**
+     * Plugboard constructor. See PairMapbase.
+     */
+    constructor(pairs) {
+        super(pairs, "Plugboard");
+    }
+}
+
+/**
+ * Base class for the Enigma machine itself. Holds rotors, a reflector, and a plugboard.
+ */
+export class EnigmaBase {
+    /**
+     * EnigmaBase constructor.
+     *
+     * @param {Object[]} rotors - List of Rotors.
+     * @param {Object} reflector - A Reflector.
+     * @param {Plugboard} plugboard - A Plugboard.
+     */
+    constructor(rotors, reflector, plugboard) {
+        this.rotors = rotors;
+        this.rotorsRev = [].concat(rotors).reverse();
+        this.reflector = reflector;
+        this.plugboard = plugboard;
+    }
+
+    /**
+     * Step the rotors forward by one.
+     *
+     * This happens before the output character is generated.
+     *
+     * Note that rotor 4, if it's there, never steps.
+     *
+     * Why is all the logic in EnigmaBase and not a nice neat method on
+     * Rotor that knows when it should advance the next item?
+     * Because the double stepping anomaly is a thing. tl;dr if the left rotor
+     * should step the next time the middle rotor steps, the middle rotor will
+     * immediately step.
+     */
+    step() {
+        const r0 = this.rotors[0];
+        const r1 = this.rotors[1];
+        r0.step();
+        // The second test here is the double-stepping anomaly
+        if (r0.steps.has(r0.pos) || r1.steps.has(Utils.mod(r1.pos + 1, 26))) {
+            r1.step();
+            if (r1.steps.has(r1.pos)) {
+                const r2 = this.rotors[2];
+                r2.step();
+            }
+        }
+    }
+
+    /**
+     * Encrypt (or decrypt) some data.
+     * Takes an arbitrary string and runs the Engima machine on that data from
+     * *its current state*, and outputs the result. Non-alphabetic characters
+     * are returned unchanged.
+     *
+     * @param {string} input - Data to encrypt.
+     * @returns {string}
+     */
+    crypt(input) {
+        let result = "";
+        for (const c of input) {
+            let letter = a2i(c, true);
+            if (letter === -1) {
+                result += c;
+                continue;
+            }
+            // First, step the rotors forward.
+            this.step();
+            // Now, run through the plugboard.
+            letter = this.plugboard.transform(letter);
+            // Then through each wheel in sequence, through the reflector, and
+            // backwards through the wheels again.
+            for (const rotor of this.rotors) {
+                letter = rotor.transform(letter);
+            }
+            letter = this.reflector.transform(letter);
+            for (const rotor of this.rotorsRev) {
+                letter = rotor.revTransform(letter);
+            }
+            // Finally, back through the plugboard.
+            letter = this.plugboard.revTransform(letter);
+            result += i2a(letter);
+        }
+        return result;
+    }
+}
+
+/**
+ * The Enigma machine itself. Holds 3-4 rotors, a reflector, and a plugboard.
+ */
+export class EnigmaMachine extends EnigmaBase {
+    /**
+     * EnigmaMachine constructor.
+     *
+     * @param {Object[]} rotors - List of Rotors.
+     * @param {Object} reflector - A Reflector.
+     * @param {Plugboard} plugboard - A Plugboard.
+     */
+    constructor(rotors, reflector, plugboard) {
+        super(rotors, reflector, plugboard);
+        if (rotors.length !== 3 && rotors.length !== 4) {
+            throw new OperationError("Enigma must have 3 or 4 rotors");
+        }
+    }
+}

src/core/lib/FileSignatures.mjs

@@ -0,0 +1,1727 @@
+/**
+ * File signatures and extractor functions
+ *
+ * @author n1474335 [n1474335@gmail.com]
+ * @copyright Crown Copyright 2018
+ * @license Apache-2.0
+ *
+ */
+import Stream from "./Stream";
+
+/**
+ * A categorised table of file types, including signatures to identify them and functions
+ * to extract them where possible.
+ */
+export const FILE_SIGNATURES = {
+    "Images": [
+        {
+            name: "Joint Photographic Experts Group image",
+            extension: "jpg,jpeg,jpe,thm,mpo",
+            mime: "image/jpeg",
+            description: "",
+            signature: {
+                0: 0xff,
+                1: 0xd8,
+                2: 0xff,
+                3: [0xc0, 0xc4, 0xdb, 0xdd, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe7, 0xe8, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xfe]
+            },
+            extractor: extractJPEG
+        },
+        {
+            name: "Graphics Interchange Format image",
+            extension: "gif",
+            mime: "image/gif",
+            description: "",
+            signature: {
+                0: 0x47, // GIF
+                1: 0x49,
+                2: 0x46,
+                3: 0x38, // 8
+                4: [0x37, 0x39], // 7|9
+                5: 0x61  // a
+            },
+            extractor: null
+        },
+        {
+            name: "Portable Network Graphics image",
+            extension: "png",
+            mime: "image/png",
+            description: "",
+            signature: {
+                0: 0x89,
+                1: 0x50, // PNG
+                2: 0x4e,
+                3: 0x47,
+                4: 0x0d,
+                5: 0x0a,
+                6: 0x1a,
+                7: 0x0a
+            },
+            extractor: extractPNG
+        },
+        {
+            name: "WEBP Image",
+            extension: "webp",
+            mime: "image/webp",
+            description: "",
+            signature: {
+                8: 0x57,
+                9: 0x45,
+                10: 0x42,
+                11: 0x50
+            },
+            extractor: null
+        },
+        {
+            name: "Camera Image File Format",
+            extension: "crw",
+            mime: "image/x-canon-crw",
+            description: "",
+            signature: {
+                6: 0x48, // HEAPCCDR
+                7: 0x45,
+                8: 0x41,
+                9: 0x50,
+                10: 0x43,
+                11: 0x43,
+                12: 0x44,
+                13: 0x52
+            },
+            extractor: null
+        },
+        { // Place before tiff check
+            name: "Canon CR2 raw image",
+            extension: "cr2",
+            mime: "image/x-canon-cr2",
+            description: "",
+            signature: [
+                {
+                    0: 0x49,
+                    1: 0x49,
+                    2: 0x2a,
+                    3: 0x0,
+                    8: 0x43,
+                    9: 0x52
+                },
+                {
+                    0: 0x4d,
+                    1: 0x4d,
+                    2: 0x0,
+                    3: 0x2a,
+                    8: 0x43,
+                    9: 0x52
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "Tagged Image File Format image",
+            extension: "tif",
+            mime: "image/tiff",
+            description: "",
+            signature: [
+                {
+                    0: 0x49,
+                    1: 0x49,
+                    2: 0x2a,
+                    3: 0x0
+                },
+                {
+                    0: 0x4d,
+                    1: 0x4d,
+                    2: 0x0,
+                    3: 0x2a
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "Bitmap image",
+            extension: "bmp",
+            mime: "image/bmp",
+            description: "",
+            signature: {
+                0: 0x42,
+                1: 0x4d,
+                7: 0x0,
+                9: 0x0,
+                14: [0x0c, 0x28, 0x38, 0x40, 0x6c, 0x7c],
+                15: 0x0,
+                16: 0x0,
+                17: 0x0
+            },
+            extractor: extractBMP
+        },
+        {
+            name: "JPEG Extended Range image",
+            extension: "jxr",
+            mime: "image/vnd.ms-photo",
+            description: "",
+            signature: {
+                0: 0x49,
+                1: 0x49,
+                2: 0xbc
+            },
+            extractor: null
+        },
+        {
+            name: "Photoshop image",
+            extension: "psd",
+            mime: "image/vnd.adobe.photoshop",
+            description: "",
+            signature: {
+                0: 0x38,
+                1: 0x42,
+                2: 0x50,
+                3: 0x53,
+                4: 0x0,
+                5: 0x1,
+                6: 0x0,
+                7: 0x0,
+                8: 0x0,
+                9: 0x0,
+                10: 0x0,
+                11: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "Paint Shop Pro image",
+            extension: "psp",
+            mime: "image/psp",
+            description: "",
+            signature: [
+                {
+                    0: 0x50, // Paint Shop Pro Im
+                    1: 0x61,
+                    2: 0x69,
+                    3: 0x6e,
+                    4: 0x74,
+                    5: 0x20,
+                    6: 0x53,
+                    7: 0x68,
+                    8: 0x6f,
+                    9: 0x70,
+                    10: 0x20,
+                    11: 0x50,
+                    12: 0x72,
+                    13: 0x6f,
+                    14: 0x20,
+                    15: 0x49,
+                    16: 0x6d
+                },
+                {
+                    0: 0x7e,
+                    1: 0x42,
+                    2: 0x4b,
+                    3: 0x0
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "Icon image",
+            extension: "ico",
+            mime: "image/x-icon",
+            description: "",
+            signature: {
+                0: 0x0,
+                1: 0x0,
+                2: 0x1,
+                3: 0x0,
+                4: [0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15],
+                5: 0x0,
+                6: [0x10, 0x20, 0x30, 0x40, 0x80],
+                7: [0x10, 0x20, 0x30, 0x40, 0x80],
+                9: 0x00,
+                10: [0x0, 0x1]
+            },
+            extractor: null
+        }
+    ],
+    "Video": [
+        { // Place before webm
+            name: "Matroska Multimedia Container",
+            extension: "mkv",
+            mime: "video/x-matroska",
+            description: "",
+            signature: {
+                31: 0x6d,
+                32: 0x61,
+                33: 0x74,
+                34: 0x72,
+                35: 0x6f,
+                36: 0x73,
+                37: 0x6b,
+                38: 0x61
+            },
+            extractor: null
+        },
+        {
+            name: "WEBM video",
+            extension: "webm",
+            mime: "video/webm",
+            description: "",
+            signature: {
+                0: 0x1a,
+                1: 0x45,
+                2: 0xdf,
+                3: 0xa3
+            },
+            extractor: null
+        },
+        {
+            name: "MPEG-4 video",
+            extension: "mp4",
+            mime: "video/mp4",
+            description: "",
+            signature: [
+                {
+                    0: 0x0,
+                    1: 0x0,
+                    2: 0x0,
+                    3: [0x18, 0x20],
+                    4: 0x66,
+                    5: 0x74,
+                    6: 0x79,
+                    7: 0x70
+                },
+                {
+                    0: 0x33, // 3gp5
+                    1: 0x67,
+                    2: 0x70,
+                    3: 0x35
+                },
+                {
+                    0: 0x0,
+                    1: 0x0,
+                    2: 0x0,
+                    3: 0x1c,
+                    4: 0x66,
+                    5: 0x74,
+                    6: 0x79,
+                    7: 0x70,
+                    8: 0x6d,
+                    9: 0x70,
+                    10: 0x34,
+                    11: 0x32,
+                    16: 0x6d, // mp41mp42isom
+                    17: 0x70,
+                    18: 0x34,
+                    19: 0x31,
+                    20: 0x6d,
+                    21: 0x70,
+                    22: 0x34,
+                    23: 0x32,
+                    24: 0x69,
+                    25: 0x73,
+                    26: 0x6f,
+                    27: 0x6d
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "M4V video",
+            extension: "m4v",
+            mime: "video/x-m4v",
+            description: "",
+            signature: {
+                0: 0x0,
+                1: 0x0,
+                2: 0x0,
+                3: 0x1c,
+                4: 0x66,
+                5: 0x74,
+                6: 0x79,
+                7: 0x70,
+                8: 0x4d,
+                9: 0x34,
+                10: 0x56
+            },
+            extractor: null
+        },
+        {
+            name: "Quicktime video",
+            extension: "mov",
+            mime: "video/quicktime",
+            description: "",
+            signature: {
+                0: 0x0,
+                1: 0x0,
+                2: 0x0,
+                3: 0x14,
+                4: 0x66,
+                5: 0x74,
+                6: 0x79,
+                7: 0x70
+            },
+            extractor: null
+        },
+        {
+            name: "Audio Video Interleave",
+            extension: "avi",
+            mime: "video/x-msvideo",
+            description: "",
+            signature: {
+                0: 0x52,
+                1: 0x49,
+                2: 0x46,
+                3: 0x46,
+                8: 0x41,
+                9: 0x56,
+                10: 0x49
+            },
+            extractor: null
+        },
+        {
+            name: "Windows Media Video",
+            extension: "wmv",
+            mime: "video/x-ms-wmv",
+            description: "",
+            signature: {
+                0: 0x30,
+                1: 0x26,
+                2: 0xb2,
+                3: 0x75,
+                4: 0x8e,
+                5: 0x66,
+                6: 0xcf,
+                7: 0x11,
+                8: 0xa6,
+                9: 0xd9
+            },
+            extractor: null
+        },
+        {
+            name: "MPEG video",
+            extension: "mpg",
+            mime: "video/mpeg",
+            description: "",
+            signature: {
+                0: 0x0,
+                1: 0x0,
+                2: 0x1,
+                3: 0xba
+            },
+            extractor: null
+        },
+        {
+            name: "Flash Video",
+            extension: "flv",
+            mime: "video/x-flv",
+            description: "",
+            signature: {
+                0: 0x46,
+                1: 0x4c,
+                2: 0x56,
+                3: 0x1
+            },
+            extractor: extractFLV
+        },
+    ],
+    "Audio": [
+        {
+            name: "Waveform Audio",
+            extension: "wav",
+            mime: "audio/x-wav",
+            description: "",
+            signature: {
+                0: 0x52,
+                1: 0x49,
+                2: 0x46,
+                3: 0x46,
+                8: 0x57,
+                9: 0x41,
+                10: 0x56,
+                11: 0x45
+            },
+            extractor: null
+        },
+        {
+            name: "OGG audio",
+            extension: "ogg",
+            mime: "audio/ogg",
+            description: "",
+            signature: {
+                0: 0x4f,
+                1: 0x67,
+                2: 0x67,
+                3: 0x53
+            },
+            extractor: null
+        },
+        {
+            name: "Musical Instrument Digital Interface audio",
+            extension: "midi",
+            mime: "audio/midi",
+            description: "",
+            signature: {
+                0: 0x4d,
+                1: 0x54,
+                2: 0x68,
+                3: 0x64
+            },
+            extractor: null
+        },
+        {
+            name: "MPEG-3 audio",
+            extension: "mp3",
+            mime: "audio/mpeg",
+            description: "",
+            signature: [
+                {
+                    0: 0x49,
+                    1: 0x44,
+                    2: 0x33
+                },
+                {
+                    0: 0xff,
+                    1: 0xfb
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "MPEG-4 Part 14 audio",
+            extension: "m4a",
+            mime: "audio/m4a",
+            description: "",
+            signature: [
+                {
+                    4: 0x66,
+                    5: 0x74,
+                    6: 0x79,
+                    7: 0x70,
+                    8: 0x4d,
+                    9: 0x34,
+                    10: 0x41
+                },
+                {
+                    0: 0x4d,
+                    1: 0x34,
+                    2: 0x41,
+                    3: 0x20
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "Free Lossless Audio Codec",
+            extension: "flac",
+            mime: "audio/x-flac",
+            description: "",
+            signature: {
+                0: 0x66,
+                1: 0x4c,
+                2: 0x61,
+                3: 0x43
+            },
+            extractor: null
+        },
+        {
+            name: "Adaptive Multi-Rate audio codec",
+            extension: "amr",
+            mime: "audio/amr",
+            description: "",
+            signature: {
+                0: 0x23,
+                1: 0x21,
+                2: 0x41,
+                3: 0x4d,
+                4: 0x52,
+                5: 0x0a
+            },
+            extractor: null
+        },
+    ],
+    "Documents": [
+        {
+            name: "Portable Document Format",
+            extension: "pdf",
+            mime: "application/pdf",
+            description: "",
+            signature: {
+                0: 0x25,
+                1: 0x50,
+                2: 0x44,
+                3: 0x46
+            },
+            extractor: extractPDF
+        },
+        {
+            name: "PostScript",
+            extension: "ps",
+            mime: "application/postscript",
+            description: "",
+            signature: {
+                0: 0x25,
+                1: 0x21
+            },
+            extractor: null
+        },
+        {
+            name: "Rich Text Format",
+            extension: "rtf",
+            mime: "application/rtf",
+            description: "",
+            signature: {
+                0: 0x7b,
+                1: 0x5c,
+                2: 0x72,
+                3: 0x74,
+                4: 0x66
+            },
+            extractor: extractRTF
+        },
+        {
+            name: "Microsoft Office documents/OLE2",
+            extension: "ole2,doc,xls,dot,ppt,xla,ppa,pps,pot,msi,sdw,db,vsd,msg",
+            mime: "application/msword,application/vnd.ms-excel,application/vnd.ms-powerpoint",
+            description: "Microsoft Office documents",
+            signature: {
+                0: 0xd0,
+                1: 0xcf,
+                2: 0x11,
+                3: 0xe0,
+                4: 0xa1,
+                5: 0xb1,
+                6: 0x1a,
+                7: 0xe1
+            },
+            extractor: null
+        },
+        {
+            name: "Microsoft Office 2007+ documents",
+            extension: "docx,xlsx,pptx",
+            mime: "application/vnd.openxmlformats-officedocument.wordprocessingml.document,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet,application/vnd.openxmlformats-officedocument.presentationml.presentation",
+            description: "",
+            signature: {
+                38: 0x5f, // _Types].xml
+                39: 0x54,
+                40: 0x79,
+                41: 0x70,
+                42: 0x65,
+                43: 0x73,
+                44: 0x5d,
+                45: 0x2e,
+                46: 0x78,
+                47: 0x6d,
+                48: 0x6c
+            },
+            extractor: extractZIP
+        },
+        {
+            name: "EPUB e-book",
+            extension: "epub",
+            mime: "application/epub+zip",
+            description: "",
+            signature: {
+                0: 0x50,
+                1: 0x4b,
+                2: 0x3,
+                3: 0x4,
+                30: 0x6d, // mimetypeapplication/epub_zip
+                31: 0x69,
+                32: 0x6d,
+                33: 0x65,
+                34: 0x74,
+                35: 0x79,
+                36: 0x70,
+                37: 0x65,
+                38: 0x61,
+                39: 0x70,
+                40: 0x70,
+                41: 0x6c,
+                42: 0x69,
+                43: 0x63,
+                44: 0x61,
+                45: 0x74,
+                46: 0x69,
+                47: 0x6f,
+                48: 0x6e,
+                49: 0x2f,
+                50: 0x65,
+                51: 0x70,
+                52: 0x75,
+                53: 0x62,
+                54: 0x2b,
+                55: 0x7a,
+                56: 0x69,
+                57: 0x70
+            },
+            extractor: extractZIP
+        },
+    ],
+    "Applications": [
+        {
+            name: "Windows Portable Executable",
+            extension: "exe,dll,drv,vxd,sys,ocx,vbx,com,fon,scr",
+            mime: "application/x-msdownload",
+            description: "",
+            signature: {
+                0: 0x4d,
+                1: 0x5a,
+                3: [0x0, 0x1, 0x2],
+                5: [0x0, 0x1, 0x2]
+            },
+            extractor: extractMZPE
+        },
+        {
+            name: "Executable and Linkable Format file",
+            extension: "elf,bin,axf,o,prx,so",
+            mime: "application/x-executable",
+            description: "Executable and Linkable Format file. No standard file extension.",
+            signature: {
+                0: 0x7f,
+                1: 0x45,
+                2: 0x4c,
+                3: 0x46
+            },
+            extractor: extractELF
+        },
+        {
+            name: "Adobe Flash",
+            extension: "swf",
+            mime: "application/x-shockwave-flash",
+            description: "",
+            signature: {
+                0: [0x43, 0x46],
+                1: 0x57,
+                2: 0x53
+            },
+            extractor: null
+        },
+        {
+            name: "Java Class",
+            extension: "class",
+            mime: "application/java-vm",
+            description: "",
+            signature: {
+                0: 0xca,
+                1: 0xfe,
+                2: 0xba,
+                3: 0xbe
+            },
+            extractor: null
+        },
+        {
+            name: "Dalvik Executable",
+            extension: "dex",
+            mime: "application/octet-stream",
+            description: "Dalvik Executable as used by Android",
+            signature: {
+                0: 0x64,
+                1: 0x65,
+                2: 0x78,
+                3: 0x0a,
+                4: 0x30,
+                5: 0x33,
+                6: 0x35,
+                7: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "Google Chrome Extension",
+            extension: "crx",
+            mime: "application/crx",
+            description: "Google Chrome extension or packaged app",
+            signature: {
+                0: 0x43,
+                1: 0x72,
+                2: 0x32,
+                3: 0x34
+            },
+            extractor: null
+        },
+    ],
+    "Archives": [
+        {
+            name: "PKZIP archive",
+            extension: "zip",
+            mime: "application/zip",
+            description: "",
+            signature: {
+                0: 0x50,
+                1: 0x4b,
+                2: [0x3, 0x5, 0x7],
+                3: [0x4, 0x6, 0x8]
+            },
+            extractor: extractZIP
+        },
+        {
+            name: "TAR archive",
+            extension: "tar",
+            mime: "application/x-tar",
+            description: "",
+            signature: {
+                257: 0x75,
+                258: 0x73,
+                259: 0x74,
+                260: 0x61,
+                261: 0x72
+            },
+            extractor: null
+        },
+        {
+            name: "Roshal Archive",
+            extension: "rar",
+            mime: "application/x-rar-compressed",
+            description: "",
+            signature: {
+                0: 0x52,
+                1: 0x61,
+                2: 0x72,
+                3: 0x21,
+                4: 0x1a,
+                5: 0x7,
+                6: [0x0, 0x1]
+            },
+            extractor: null
+        },
+        {
+            name: "Gzip",
+            extension: "gz",
+            mime: "application/gzip",
+            description: "",
+            signature: {
+                0: 0x1f,
+                1: 0x8b,
+                2: 0x8
+            },
+            extractor: extractGZIP
+        },
+        {
+            name: "Bzip2",
+            extension: "bz2",
+            mime: "application/x-bzip2",
+            description: "",
+            signature: {
+                0: 0x42,
+                1: 0x5a,
+                2: 0x68
+            },
+            extractor: null
+        },
+        {
+            name: "7zip",
+            extension: "7z",
+            mime: "application/x-7z-compressed",
+            description: "",
+            signature: {
+                0: 0x37,
+                1: 0x7a,
+                2: 0xbc,
+                3: 0xaf,
+                4: 0x27,
+                5: 0x1c
+            },
+            extractor: null
+        },
+        {
+            name: "Zlib Deflate",
+            extension: "zlib",
+            mime: "application/x-deflate",
+            description: "",
+            signature: {
+                0: 0x78,
+                1: [0x1, 0x9c, 0xda, 0x5e]
+            },
+            extractor: extractZlib
+        },
+        {
+            name: "xz compression",
+            extension: "xz",
+            mime: "application/x-xz",
+            description: "",
+            signature: {
+                0: 0xfd,
+                1: 0x37,
+                2: 0x7a,
+                3: 0x58,
+                4: 0x5a,
+                5: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "Tarball",
+            extension: "tar.z",
+            mime: "application/x-gtar",
+            description: "",
+            signature: {
+                0: 0x1f,
+                1: [0x9d, 0xa0]
+            },
+            extractor: null
+        },
+        {
+            name: "ISO disk image",
+            extension: "iso",
+            mime: "application/octet-stream",
+            description: "ISO 9660 CD/DVD image file",
+            signature: [
+                {
+                    0x8001: 0x43,
+                    0x8002: 0x44,
+                    0x8003: 0x30,
+                    0x8004: 0x30,
+                    0x8005: 0x31
+                },
+                {
+                    0x8801: 0x43,
+                    0x8802: 0x44,
+                    0x8803: 0x30,
+                    0x8804: 0x30,
+                    0x8805: 0x31
+                },
+                {
+                    0x9001: 0x43,
+                    0x9002: 0x44,
+                    0x9003: 0x30,
+                    0x9004: 0x30,
+                    0x9005: 0x31
+                }
+            ],
+            extractor: null
+        },
+        {
+            name: "Virtual Machine Disk",
+            extension: "vmdk",
+            mime: "application/vmdk,application/x-virtualbox-vmdk",
+            description: "",
+            signature: {
+                0: 0x4b,
+                1: 0x44,
+                2: 0x4d
+            },
+            extractor: null
+        },
+    ],
+    "Miscellaneous": [
+        {
+            name: "UTF-8 text file",
+            extension: "txt",
+            mime: "text/plain",
+            description: "UTF-8 encoded Unicode byte order mark, commonly but not exclusively seen in text files.",
+            signature: {
+                0: 0xef,
+                1: 0xbb,
+                2: 0xbf
+            },
+            extractor: null
+        },
+        { // Place before UTF-16 LE file
+            name: "UTF-32 LE file",
+            extension: "utf32le",
+            mime: "charset/utf32le",
+            description: "Little-endian UTF-32 encoded Unicode byte order mark.",
+            signature: {
+                0: 0xff,
+                1: 0xfe,
+                2: 0x00,
+                3: 0x00
+            },
+            extractor: null
+        },
+        {
+            name: "UTF-16 LE file",
+            extension: "utf16le",
+            mime: "charset/utf16le",
+            description: "Little-endian UTF-16 encoded Unicode byte order mark.",
+            signature: {
+                0: 0xff,
+                1: 0xfe
+            },
+            extractor: null
+        },
+        {
+            name: "Web Open Font Format",
+            extension: "woff",
+            mime: "application/font-woff",
+            description: "",
+            signature: {
+                0: 0x77,
+                1: 0x4f,
+                2: 0x46,
+                3: 0x46,
+                4: 0x0,
+                5: 0x1,
+                6: 0x0,
+                7: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "Web Open Font Format 2",
+            extension: "woff2",
+            mime: "application/font-woff",
+            description: "",
+            signature: {
+                0: 0x77,
+                1: 0x4f,
+                2: 0x46,
+                3: 0x32,
+                4: 0x0,
+                5: 0x1,
+                6: 0x0,
+                7: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "Embedded OpenType font",
+            extension: "eot",
+            mime: "application/octet-stream",
+            description: "",
+            signature: [
+                {
+                    8: 0x2,
+                    9: 0x0,
+                    10: 0x1,
+                    34: 0x4c,
+                    35: 0x50
+                },
+                {
+                    8: 0x1,
+                    9: 0x0,
+                    10: 0x0,
+                    34: 0x4c,
+                    35: 0x50
+                },
+                {
+                    8: 0x2,
+                    9: 0x0,
+                    10: 0x2,
+                    34: 0x4c,
+                    35: 0x50
+                },
+            ],
+            extractor: null
+        },
+        {
+            name: "TrueType Font",
+            extension: "ttf",
+            mime: "application/font-sfnt",
+            description: "",
+            signature: {
+                0: 0x0,
+                1: 0x1,
+                2: 0x0,
+                3: 0x0,
+                4: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "OpenType Font",
+            extension: "otf",
+            mime: "application/font-sfnt",
+            description: "",
+            signature: {
+                0: 0x4f,
+                1: 0x54,
+                2: 0x54,
+                3: 0x4f,
+                4: 0x0
+            },
+            extractor: null
+        },
+        {
+            name: "SQLite",
+            extension: "sqlite",
+            mime: "application/x-sqlite3",
+            description: "",
+            signature: {
+                0: 0x53,
+                1: 0x51,
+                2: 0x4c,
+                3: 0x69
+            },
+            extractor: null
+        },
+    ]
+};
+
+
+/**
+ * JPEG extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractJPEG(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    while (stream.hasMore()) {
+        const marker = stream.getBytes(2);
+        if (marker[0] !== 0xff) throw new Error(`Invalid marker while parsing JPEG at pos ${stream.position}: ${marker}`);
+
+        let segmentSize = 0;
+        switch (marker[1]) {
+            // No length
+            case 0xd8: // Start of Image
+            case 0x01: // For temporary use in arithmetic coding
+                break;
+            case 0xd9: // End found
+                return stream.carve();
+
+            // Variable size segment
+            case 0xc0: // Start of frame (Baseline DCT)
+            case 0xc1: // Start of frame (Extended sequential DCT)
+            case 0xc2: // Start of frame (Progressive DCT)
+            case 0xc3: // Start of frame (Lossless sequential)
+            case 0xc4: // Define Huffman Table
+            case 0xc5: // Start of frame (Differential sequential DCT)
+            case 0xc6: // Start of frame (Differential progressive DCT)
+            case 0xc7: // Start of frame (Differential lossless)
+            case 0xc8: // Reserved for JPEG extensions
+            case 0xc9: // Start of frame (Extended sequential DCT)
+            case 0xca: // Start of frame (Progressive DCT)
+            case 0xcb: // Start of frame (Lossless sequential)
+            case 0xcc: // Define arithmetic conditioning table
+            case 0xcd: // Start of frame (Differential sequential DCT)
+            case 0xce: // Start of frame (Differential progressive DCT)
+            case 0xcf: // Start of frame (Differential lossless)
+            case 0xdb: // Define Quantization Table
+            case 0xde: // Define hierarchical progression
+            case 0xe0: // Application-specific
+            case 0xe1: // Application-specific
+            case 0xe2: // Application-specific
+            case 0xe3: // Application-specific
+            case 0xe4: // Application-specific
+            case 0xe5: // Application-specific
+            case 0xe6: // Application-specific
+            case 0xe7: // Application-specific
+            case 0xe8: // Application-specific
+            case 0xe9: // Application-specific
+            case 0xea: // Application-specific
+            case 0xeb: // Application-specific
+            case 0xec: // Application-specific
+            case 0xed: // Application-specific
+            case 0xee: // Application-specific
+            case 0xef: // Application-specific
+            case 0xfe: // Comment
+                segmentSize = stream.readInt(2, "be");
+                stream.position += segmentSize - 2;
+                break;
+
+            // 1 byte
+            case 0xdf: // Expand reference image
+                stream.position++;
+                break;
+
+            // 2 bytes
+            case 0xdc: // Define number of lines
+            case 0xdd: // Define restart interval
+                stream.position += 2;
+                break;
+
+            // Start scan
+            case 0xda: // Start of scan
+                segmentSize = stream.readInt(2, "be");
+                stream.position += segmentSize - 2;
+                stream.continueUntil(0xff);
+                break;
+
+            // Continue through encoded data
+            case 0x00: // Byte stuffing
+            case 0xd0: // Restart
+            case 0xd1: // Restart
+            case 0xd2: // Restart
+            case 0xd3: // Restart
+            case 0xd4: // Restart
+            case 0xd5: // Restart
+            case 0xd6: // Restart
+            case 0xd7: // Restart
+                stream.continueUntil(0xff);
+                break;
+
+            default:
+                stream.continueUntil(0xff);
+                break;
+        }
+    }
+
+    throw new Error("Unable to parse JPEG successfully");
+}
+
+
+/**
+ * Portable executable extractor.
+ * Assumes that the offset refers to an MZ header.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractMZPE(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Move to PE header pointer
+    stream.moveTo(0x3c);
+    const peAddress = stream.readInt(4, "le");
+
+    // Move to PE header
+    stream.moveTo(peAddress);
+
+    // Get number of sections
+    stream.moveForwardsBy(6);
+    const numSections = stream.readInt(2, "le");
+
+    // Get optional header size
+    stream.moveForwardsBy(12);
+    const optionalHeaderSize = stream.readInt(2, "le");
+
+    // Move past optional header to section header
+    stream.moveForwardsBy(2 + optionalHeaderSize);
+
+    // Move to final section header
+    stream.moveForwardsBy((numSections - 1) * 0x28);
+
+    // Get raw data info
+    stream.moveForwardsBy(16);
+    const rawDataSize = stream.readInt(4, "le");
+    const rawDataAddress = stream.readInt(4, "le");
+
+    // Move to end of final section
+    stream.moveTo(rawDataAddress + rawDataSize);
+
+    return stream.carve();
+}
+
+
+/**
+ * PDF extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractPDF(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Find end-of-file marker (%%EOF)
+    stream.continueUntil([0x25, 0x25, 0x45, 0x4f, 0x46]);
+    stream.moveForwardsBy(5);
+    stream.consumeIf(0x0d);
+    stream.consumeIf(0x0a);
+
+    return stream.carve();
+}
+
+
+/**
+ * ZIP extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractZIP(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Find End of central directory record
+    stream.continueUntil([0x50, 0x4b, 0x05, 0x06]);
+
+    // Get comment length and consume
+    stream.moveForwardsBy(20);
+    const commentLength = stream.readInt(2, "le");
+    stream.moveForwardsBy(commentLength);
+
+    return stream.carve();
+}
+
+
+/**
+ * PNG extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractPNG(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Move past signature to first chunk
+    stream.moveForwardsBy(8);
+
+    let chunkSize = 0,
+        chunkType = "";
+
+    while (chunkType !== "IEND") {
+        chunkSize = stream.readInt(4, "be");
+        chunkType = stream.readString(4);
+
+        // Chunk data size + CRC checksum
+        stream.moveForwardsBy(chunkSize + 4);
+    }
+
+
+    return stream.carve();
+}
+
+
+/**
+ * BMP extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractBMP(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Move past header
+    stream.moveForwardsBy(2);
+
+    // Read full file size
+    const bmpSize = stream.readInt(4, "le");
+
+    // Move to end of file (file size minus header and size field)
+    stream.moveForwardsBy(bmpSize - 6);
+
+    return stream.carve();
+}
+
+
+/**
+ * FLV extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractFLV(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Move past signature, version and flags
+    stream.moveForwardsBy(5);
+
+    // Read header size
+    const headerSize = stream.readInt(4, "be");
+
+    // Skip through the rest of the header
+    stream.moveForwardsBy(headerSize - 9);
+
+    let tagSize = -11; // Fake size of previous tag header
+    while (stream.hasMore()) {
+        const prevTagSize = stream.readInt(4, "be");
+        const tagType = stream.readInt(1);
+
+        if ([8, 9, 18].indexOf(tagType) < 0) {
+            // This tag is not valid
+            stream.moveBackwardsBy(1);
+            break;
+        }
+
+        if (prevTagSize !== (tagSize + 11)) {
+            // Previous tag was not valid, reverse back over this header
+            // and the previous tag body and header
+            stream.moveBackwardsBy(tagSize + 11 + 5);
+            break;
+        }
+
+        tagSize = stream.readInt(3, "be");
+
+        // Move past the rest of the tag header and payload
+        stream.moveForwardsBy(7 + tagSize);
+    }
+
+    return stream.carve();
+}
+
+
+/**
+ * RTF extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractRTF(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    let openTags = 0;
+
+    if (stream.readInt(1) !== 0x7b) { // {
+        throw new Error("Not a valid RTF file");
+    } else {
+        openTags++;
+    }
+
+    while (openTags > 0 && stream.hasMore()) {
+        switch (stream.readInt(1)) {
+            case 0x7b: // {
+                openTags++;
+                break;
+            case 0x7d: // }
+                openTags--;
+                break;
+            case 0x5c: // \
+                // Consume any more escapes and then skip over the next character
+                stream.consumeIf(0x5c);
+                stream.position++;
+                break;
+            default:
+                break;
+        }
+    }
+
+    return stream.carve();
+}
+
+
+/**
+ * GZIP extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractGZIP(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+
+    /* HEADER */
+
+    // Skip over signature and compression method
+    stream.moveForwardsBy(3);
+
+    // Read flags
+    const flags = stream.readInt(1);
+
+    // Skip over last modification time
+    stream.moveForwardsBy(4);
+
+    // Read compression flags
+    stream.readInt(1);
+
+    // Skip over OS
+    stream.moveForwardsBy(1);
+
+
+    /* OPTIONAL HEADERS */
+
+    // Extra fields
+    if (flags & 0x4) {
+        const extraFieldsSize = stream.readInt(2, "le");
+        stream.moveForwardsby(extraFieldsSize);
+    }
+
+    // Original filename
+    if (flags & 0x8) {
+        stream.continueUntil(0x00);
+        stream.moveForwardsBy(1);
+    }
+
+    // Comment
+    if (flags & 0x10) {
+        stream.continueUntil(0x00);
+        stream.moveForwardsBy(1);
+    }
+
+    // Checksum
+    if (flags & 0x2) {
+        stream.moveForwardsBy(2);
+    }
+
+
+    /* DEFLATE DATA */
+
+    parseDEFLATE(stream);
+
+
+    /* FOOTER */
+
+    // Skip over checksum and size of original uncompressed input
+    stream.moveForwardsBy(8);
+
+    return stream.carve();
+}
+
+
+/**
+ * Zlib extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractZlib(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Skip over CMF
+    stream.moveForwardsBy(1);
+
+    // Read flags
+    const flags = stream.readInt(1);
+
+    // Skip over preset dictionary checksum
+    if (flags & 0x20) {
+        stream.moveForwardsBy(4);
+    }
+
+    // Parse DEFLATE stream
+    parseDEFLATE(stream);
+
+    // Skip over final checksum
+    stream.moveForwardsBy(4);
+
+    return stream.carve();
+}
+
+
+/**
+ * ELF extractor.
+ *
+ * @param {Uint8Array} bytes
+ * @param {number} offset
+ * @returns {Uint8Array}
+ */
+export function extractELF(bytes, offset) {
+    const stream = new Stream(bytes.slice(offset));
+
+    // Skip over magic number
+    stream.moveForwardsBy(4);
+
+    // Read architecture (x86 == 1, x64 == 2)
+    const x86 = stream.readInt(1) === 1;
+
+    // Read endianness (1 == little, 2 == big)
+    const endian = stream.readInt(1) === 1 ? "le" : "be";
+
+    // Skip over header values
+    stream.moveForwardsBy(x86 ? 26 : 34);
+
+    // Read section header table offset
+    const shoff = x86 ? stream.readInt(4, endian) : stream.readInt(8, endian);
+
+    // Skip over flags, header size and program header size and entries
+    stream.moveForwardsBy(10);
+
+    // Read section header table entry size
+    const shentsize = stream.readInt(2, endian);
+
+    // Read number of entries in the section header table
+    const shnum = stream.readInt(2, endian);
+
+    // Jump to section header table
+    stream.moveTo(shoff);
+
+    // Move past each section header
+    stream.moveForwardsBy(shentsize * shnum);
+
+    return stream.carve();
+}
+
+
+// Construct required Huffman Tables
+const fixedLiteralTableLengths = new Array(288);
+for (let i = 0; i < fixedLiteralTableLengths.length; i++) {
+    fixedLiteralTableLengths[i] =
+        (i <= 143) ? 8 :
+            (i <= 255) ? 9 :
+                (i <= 279) ? 7 :
+                    8;
+}
+const fixedLiteralTable = buildHuffmanTable(fixedLiteralTableLengths);
+const fixedDistanceTableLengths = new Array(30).fill(5);
+const fixedDistanceTable = buildHuffmanTable(fixedDistanceTableLengths);
+const huffmanOrder = [16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15];
+
+/**
+ * Steps through a DEFLATE stream
+ *
+ * @param {Stream} stream
+ */
+function parseDEFLATE(stream) {
+    // Parse DEFLATE data
+    let finalBlock = 0;
+
+    while (!finalBlock) {
+        // Read header
+        finalBlock = stream.readBits(1);
+        const blockType = stream.readBits(2);
+
+        if (blockType === 0) {
+            /* No compression */
+
+            // Consume the rest of the current byte
+            stream.moveForwardsBy(1);
+            // Read the block length value
+            const blockLength = stream.readInt(2, "le");
+            // Move to the end of this block
+            stream.moveForwardsBy(2 + blockLength);
+        } else if (blockType === 1) {
+            /* Fixed Huffman */
+
+            parseHuffmanBlock(stream, fixedLiteralTable, fixedDistanceTable);
+        } else if (blockType === 2) {
+            /* Dynamic Huffman */
+
+            // Read the number of liternal and length codes
+            const hlit = stream.readBits(5) + 257;
+            // Read the number of distance codes
+            const hdist = stream.readBits(5) + 1;
+            // Read the number of code lengths
+            const hclen = stream.readBits(4) + 4;
+
+            // Parse code lengths
+            const codeLengths = new Uint8Array(huffmanOrder.length);
+            for (let i = 0; i < hclen; i++) {
+                codeLengths[huffmanOrder[i]] = stream.readBits(3);
+            }
+
+            // Parse length table
+            const codeLengthsTable = buildHuffmanTable(codeLengths);
+            const lengthTable = new Uint8Array(hlit + hdist);
+
+            let code, repeat, prev;
+            for (let i = 0; i < hlit + hdist;) {
+                code = readHuffmanCode(stream, codeLengthsTable);
+                switch (code) {
+                    case 16:
+                        repeat = 3 + stream.readBits(2);
+                        while (repeat--) lengthTable[i++] = prev;
+                        break;
+                    case 17:
+                        repeat = 3 + stream.readBits(3);
+                        while (repeat--) lengthTable[i++] = 0;
+                        prev = 0;
+                        break;
+                    case 18:
+                        repeat = 11 + stream.readBits(7);
+                        while (repeat--) lengthTable[i++] = 0;
+                        prev = 0;
+                        break;
+                    default:
+                        lengthTable[i++] = code;
+                        prev = code;
+                        break;
+                }
+            }
+
+            const dynamicLiteralTable = buildHuffmanTable(lengthTable.subarray(0, hlit));
+            const dynamicDistanceTable = buildHuffmanTable(lengthTable.subarray(hlit));
+
+            parseHuffmanBlock(stream, dynamicLiteralTable, dynamicDistanceTable);
+        } else {
+            throw new Error(`Invalid block type while parsing DEFLATE stream at pos ${stream.position}`);
+        }
+    }
+
+    // Consume final byte if it has not been fully consumed yet
+    if (stream.bitPos > 0)
+        stream.moveForwardsBy(1);
+}
+
+
+// Static length tables
+const lengthExtraTable = [
+    0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 0, 0
+];
+const distanceExtraTable = [
+    0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13
+];
+
+/**
+ * Parses a Huffman Block given the literal and distance tables
+ *
+ * @param {Stream} stream
+ * @param {Uint32Array} litTab
+ * @param {Uint32Array} distTab
+ */
+function parseHuffmanBlock(stream, litTab, distTab) {
+    let code;
+    let loops = 0;
+    while ((code = readHuffmanCode(stream, litTab))) {
+        // console.log("Code: " + code + " (" + Utils.chr(code) + ") " + Utils.bin(code));
+
+        // End of block
+        if (code === 256) break;
+
+        // Detect probably infinite loops
+        if (++loops > 10000)
+            throw new Error("Caught in probable infinite loop while parsing Huffman Block");
+
+        // Literal
+        if (code < 256) continue;
+
+        // Length code
+        stream.readBits(lengthExtraTable[code - 257]);
+
+        // Dist code
+        code = readHuffmanCode(stream, distTab);
+        stream.readBits(distanceExtraTable[code]);
+    }
+}
+
+
+/**
+ * Builds a Huffman table given the relevant code lengths
+ *
+ * @param {Array} lengths
+ * @returns {Array} result
+ * @returns {Uint32Array} result.table
+ * @returns {number} result.maxCodeLength
+ * @returns {number} result.minCodeLength
+ */
+function buildHuffmanTable(lengths) {
+    const maxCodeLength = Math.max.apply(Math, lengths);
+    const minCodeLength = Math.min.apply(Math, lengths);
+    const size = 1 << maxCodeLength;
+    const table = new Uint32Array(size);
+
+    for (let bitLength = 1, code = 0, skip = 2; bitLength <= maxCodeLength;) {
+        for (let i = 0; i < lengths.length; i++) {
+            if (lengths[i] === bitLength) {
+                let reversed, rtemp, j;
+                for (reversed = 0, rtemp = code, j = 0; j < bitLength; j++) {
+                    reversed = (reversed << 1) | (rtemp & 1);
+                    rtemp >>= 1;
+                }
+
+                const value = (bitLength << 16) | i;
+                for (let j = reversed; j < size; j += skip) {
+                    table[j] = value;
+                }
+
+                code++;
+            }
+        }
+
+        bitLength++;
+        code <<= 1;
+        skip <<= 1;
+    }
+
+    return [table, maxCodeLength, minCodeLength];
+}
+
+
+/**
+ * Reads the next Huffman code from the stream, given the relevant code table
+ *
+ * @param {Stream} stream
+ * @param {Uint32Array} table
+ * @returns {number}
+ */
+function readHuffmanCode(stream, table) {
+    const [codeTable, maxCodeLength] = table;
+
+    // Read max length
+    const bitsBuf = stream.readBits(maxCodeLength);
+    const codeWithLength = codeTable[bitsBuf & ((1 << maxCodeLength) - 1)];
+    const codeLength = codeWithLength >>> 16;
+
+    if (codeLength > maxCodeLength) {
+        throw new Error(`Invalid Huffman Code length while parsing DEFLATE block at pos ${stream.position}: ${codeLength}`);
+    }
+
+    stream.moveBackwardsByBits(maxCodeLength - codeLength);
+
+    return codeWithLength & 0xffff;
+}

src/core/lib/FileType.mjs

@@ -0,0 +1,263 @@
+/**
+ * File type functions
+ *
+ * @author n1474335 [n1474335@gmail.com]
+ * @copyright Crown Copyright 2018
+ * @license Apache-2.0
+ *
+ */
+import {FILE_SIGNATURES} from "./FileSignatures";
+import {sendStatusMessage} from "../Utils";
+
+
+/**
+ * Checks whether a signature matches a buffer.
+ *
+ * @param {Object|Object[]} sig - A dictionary of offsets with values assigned to them.
+ *   These values can be numbers for static checks, arrays of potential valid matches,
+ *   or bespoke functions to check the validity of the buffer value at that offset.
+ * @param {Uint8Array} buf
+ * @param {number} [offset=0] Where in the buffer to start searching from
+ * @returns {boolean}
+ */
+function signatureMatches(sig, buf, offset=0) {
+    // Using a length check seems to be more performant than `sig instanceof Array`
+    if (sig.length) {
+        // sig is an Array - return true if any of them match
+        // The following `reduce` method is nice, but performance matters here, so we
+        // opt for a faster, if less elegant, for loop.
+        // return sig.reduce((acc, s) => acc || bytesMatch(s, buf, offset), false);
+        for (let i = 0; i < sig.length; i++) {
+            if (bytesMatch(sig[i], buf, offset)) return true;
+        }
+        return false;
+    } else {
+        return bytesMatch(sig, buf, offset);
+    }
+}
+
+
+/**
+ * Checks whether a set of bytes match the given buffer.
+ *
+ * @param {Object} sig - A dictionary of offsets with values assigned to them.
+ *   These values can be numbers for static checks, arrays of potential valid matches,
+ *   or bespoke functions to check the validity of the buffer value at that offset.
+ * @param {Uint8Array} buf
+ * @param {number} [offset=0] Where in the buffer to start searching from
+ * @returns {boolean}
+ */
+function bytesMatch(sig, buf, offset=0) {
+    for (const sigoffset in sig) {
+        const pos = parseInt(sigoffset, 10) + offset;
+        switch (typeof sig[sigoffset]) {
+            case "number": // Static check
+                if (buf[pos] !== sig[sigoffset])
+                    return false;
+                break;
+            case "object": // Array of options
+                if (sig[sigoffset].indexOf(buf[pos]) < 0)
+                    return false;
+                break;
+            case "function": // More complex calculation
+                if (!sig[sigoffset](buf[pos]))
+                    return false;
+                break;
+            default:
+                throw new Error(`Unrecognised signature type at offset ${sigoffset}`);
+        }
+    }
+    return true;
+}
+
+
+/**
+ * Given a buffer, detects magic byte sequences at specific positions and returns the
+ * extension and mime type.
+ *
+ * @param {Uint8Array} buf
+ * @param {string[]} [categories=All] - Which categories of file to look for
+ * @returns {Object[]} types
+ * @returns {string} type.name - Name of file type
+ * @returns {string} type.ext - File extension
+ * @returns {string} type.mime - Mime type
+ * @returns {string} [type.desc] - Description
+ */
+export function detectFileType(buf, categories=Object.keys(FILE_SIGNATURES)) {
+    if (!(buf && buf.length > 1)) {
+        return [];
+    }
+
+    const matchingFiles = [];
+    const signatures = {};
+
+    for (const cat in FILE_SIGNATURES) {
+        if (categories.includes(cat)) {
+            signatures[cat] = FILE_SIGNATURES[cat];
+        }
+    }
+
+    for (const cat in signatures) {
+        const category = signatures[cat];
+
+        category.forEach(filetype => {
+            if (signatureMatches(filetype.signature, buf)) {
+                matchingFiles.push(filetype);
+            }
+        });
+    }
+    return matchingFiles;
+}
+
+
+/**
+ * Given a buffer, searches for magic byte sequences at all possible positions and returns
+ * the extensions and mime types.
+ *
+ * @param {Uint8Array} buf
+ * @param {string[]} [categories=All] - Which categories of file to look for
+ * @returns {Object[]} foundFiles
+ * @returns {number} foundFiles.offset - The position in the buffer at which this file was found
+ * @returns {Object} foundFiles.fileDetails
+ * @returns {string} foundFiles.fileDetails.name - Name of file type
+ * @returns {string} foundFiles.fileDetails.ext - File extension
+ * @returns {string} foundFiles.fileDetails.mime - Mime type
+ * @returns {string} [foundFiles.fileDetails.desc] - Description
+ */
+export function scanForFileTypes(buf, categories=Object.keys(FILE_SIGNATURES)) {
+    if (!(buf && buf.length > 1)) {
+        return [];
+    }
+
+    const foundFiles = [];
+    const signatures = {};
+
+    for (const cat in FILE_SIGNATURES) {
+        if (categories.includes(cat)) {
+            signatures[cat] = FILE_SIGNATURES[cat];
+        }
+    }
+
+    for (const cat in signatures) {
+        const category = signatures[cat];
+
+        for (let i = 0; i < category.length; i++) {
+            const filetype = category[i];
+            const sigs = filetype.signature.length ? filetype.signature : [filetype.signature];
+
+            sigs.forEach(sig => {
+                let pos = 0;
+                while ((pos = locatePotentialSig(buf, sig, pos)) >= 0) {
+                    if (bytesMatch(sig, buf, pos)) {
+                        sendStatusMessage(`Found potential signature for ${filetype.name} at pos ${pos}`);
+                        foundFiles.push({
+                            offset: pos,
+                            fileDetails: filetype
+                        });
+                    }
+                    pos++;
+                }
+            });
+        }
+    }
+
+    // Return found files in order of increasing offset
+    return foundFiles.sort((a, b) => {
+        return a.offset - b.offset;
+    });
+}
+
+
+/**
+ * Fastcheck function to quickly scan the buffer for the first byte in a signature.
+ *
+ * @param {Uint8Array} buf - The buffer to search
+ * @param {Object} sig - A single signature object (Not an array of signatures)
+ * @param {number} offset - Where to start search from
+ * @returs {number} The position of the match or -1 if one cannot be found.
+ */
+function locatePotentialSig(buf, sig, offset) {
+    // Find values for first key and value in sig
+    const k = parseInt(Object.keys(sig)[0], 10);
+    const v = Object.values(sig)[0];
+    switch (typeof v) {
+        case "number":
+            return buf.indexOf(v, offset + k) - k;
+        case "object":
+            for (let i = offset + k; i < buf.length; i++) {
+                if (v.indexOf(buf[i]) >= 0) return i - k;
+            }
+            return -1;
+        case "function":
+            for (let i = offset + k; i < buf.length; i++) {
+                if (v(buf[i])) return i - k;
+            }
+            return -1;
+        default:
+            throw new Error("Unrecognised signature type");
+    }
+}
+
+
+/**
+ * Detects whether the given buffer is a file of the type specified.
+ *
+ * @param {string|RegExp} type
+ * @param {Uint8Array} buf
+ * @returns {string|false} The mime type or false if the type does not match
+ */
+export function isType(type, buf) {
+    const types = detectFileType(buf);
+
+    if (!(types && types.length)) return false;
+
+    if (typeof type === "string") {
+        return types.reduce((acc, t) => {
+            const mime = t.mime.startsWith(type) ? t.mime : false;
+            return acc || mime;
+        }, false);
+    } else if (type instanceof RegExp) {
+        return types.reduce((acc, t) => {
+            const mime = type.test(t.mime) ? t.mime : false;
+            return acc || mime;
+        }, false);
+    } else {
+        throw new Error("Invalid type input.");
+    }
+}
+
+
+/**
+ * Detects whether the given buffer contains an image file.
+ *
+ * @param {Uint8Array} buf
+ * @returns {string|false} The mime type or false if the type does not match
+ */
+export function isImage(buf) {
+    return isType("image", buf);
+}
+
+
+/**
+ * Attempts to extract a file from a data stream given its offset and extractor function.
+ *
+ * @param {Uint8Array} bytes
+ * @param {Object} fileDetail
+ * @param {string} fileDetail.mime
+ * @param {string} fileDetail.extension
+ * @param {Function} fileDetail.extractor
+ * @param {number} offset
+ * @returns {File}
+ */
+export function extractFile(bytes, fileDetail, offset) {
+    if (fileDetail.extractor) {
+        sendStatusMessage(`Attempting to extract ${fileDetail.name} at pos ${offset}...`);
+        const fileData = fileDetail.extractor(bytes, offset);
+        const ext = fileDetail.extension.split(",")[0];
+        return new File([fileData], `extracted_at_0x${offset.toString(16)}.${ext}`, {
+            type: fileDetail.mime
+        });
+    }
+
+    throw new Error(`No extraction algorithm available for "${fileDetail.mime}" files`);
+}

src/core/lib/Magic.mjs

@@ -2,6 +2,7 @@ import OperationConfig from "../config/OperationConfig.json";
 import Utils from "../Utils";
 import Recipe from "../Recipe";
 import Dish from "../Dish";
+import {detectFileType} from "./FileType";
 import chiSquared from "chi-squared";
 
 /**
@@ -92,7 +93,14 @@ class Magic {
      * @returns {string} [type.desc] - Description
      */
     detectFileType() {
-        return Magic.magicFileType(this.inputBuffer);
+        const fileType = detectFileType(this.inputBuffer);
+
+        if (!fileType.length) return null;
+        return {
+            ext: fileType[0].extension,
+            mime: fileType[0].mime,
+            desc: fileType[0].description
+        };
     }
 
     /**
@@ -785,452 +793,9 @@ class Magic {
         }[code];
     }
 
-
-    /**
-     * Given a buffer, detects magic byte sequences at specific positions and returns the
-     * extension and mime type.
-     *
-     * @param {Uint8Array} buf
-     * @returns {Object} type
-     * @returns {string} type.ext - File extension
-     * @returns {string} type.mime - Mime type
-     * @returns {string} [type.desc] - Description
-     */
-    static magicFileType(buf) {
-        if (!(buf && buf.length > 1)) {
-            return null;
-        }
-
-        if (buf[0] === 0xFF && buf[1] === 0xD8 && buf[2] === 0xFF) {
-            return {
-                ext: "jpg",
-                mime: "image/jpeg"
-            };
-        }
-
-        if (buf[0] === 0x89 && buf[1] === 0x50 && buf[2] === 0x4E && buf[3] === 0x47) {
-            return {
-                ext: "png",
-                mime: "image/png"
-            };
-        }
-
-        if (buf[0] === 0x47 && buf[1] === 0x49 && buf[2] === 0x46) {
-            return {
-                ext: "gif",
-                mime: "image/gif"
-            };
-        }
-
-        if (buf[8] === 0x57 && buf[9] === 0x45 && buf[10] === 0x42 && buf[11] === 0x50) {
-            return {
-                ext: "webp",
-                mime: "image/webp"
-            };
-        }
-
-        // needs to be before `tif` check
-        if (((buf[0] === 0x49 && buf[1] === 0x49 && buf[2] === 0x2A && buf[3] === 0x0) || (buf[0] === 0x4D && buf[1] === 0x4D && buf[2] === 0x0 && buf[3] === 0x2A)) && buf[8] === 0x43 && buf[9] === 0x52) {
-            return {
-                ext: "cr2",
-                mime: "image/x-canon-cr2"
-            };
-        }
-
-        if ((buf[0] === 0x49 && buf[1] === 0x49 && buf[2] === 0x2A && buf[3] === 0x0) || (buf[0] === 0x4D && buf[1] === 0x4D && buf[2] === 0x0 && buf[3] === 0x2A)) {
-            return {
-                ext: "tif",
-                mime: "image/tiff"
-            };
-        }
-
-        if (buf[0] === 0x42 && buf[1] === 0x4D) {
-            return {
-                ext: "bmp",
-                mime: "image/bmp"
-            };
-        }
-
-        if (buf[0] === 0x49 && buf[1] === 0x49 && buf[2] === 0xBC) {
-            return {
-                ext: "jxr",
-                mime: "image/vnd.ms-photo"
-            };
-        }
-
-        if (buf[0] === 0x38 && buf[1] === 0x42 && buf[2] === 0x50 && buf[3] === 0x53) {
-            return {
-                ext: "psd",
-                mime: "image/vnd.adobe.photoshop"
-            };
-        }
-
-        // needs to be before `zip` check
-        if (buf[0] === 0x50 && buf[1] === 0x4B && buf[2] === 0x3 && buf[3] === 0x4 && buf[30] === 0x6D && buf[31] === 0x69 && buf[32] === 0x6D && buf[33] === 0x65 && buf[34] === 0x74 && buf[35] === 0x79 && buf[36] === 0x70 && buf[37] === 0x65 && buf[38] === 0x61 && buf[39] === 0x70 && buf[40] === 0x70 && buf[41] === 0x6C && buf[42] === 0x69 && buf[43] === 0x63 && buf[44] === 0x61 && buf[45] === 0x74 && buf[46] === 0x69 && buf[47] === 0x6F && buf[48] === 0x6E && buf[49] === 0x2F && buf[50] === 0x65 && buf[51] === 0x70 && buf[52] === 0x75 && buf[53] === 0x62 && buf[54] === 0x2B && buf[55] === 0x7A && buf[56] === 0x69 && buf[57] === 0x70) {
-            return {
-                ext: "epub",
-                mime: "application/epub+zip"
-            };
-        }
-
-        if (buf[0] === 0x50 && buf[1] === 0x4B && (buf[2] === 0x3 || buf[2] === 0x5 || buf[2] === 0x7) && (buf[3] === 0x4 || buf[3] === 0x6 || buf[3] === 0x8)) {
-            return {
-                ext: "zip",
-                mime: "application/zip"
-            };
-        }
-
-        if (buf[257] === 0x75 && buf[258] === 0x73 && buf[259] === 0x74 && buf[260] === 0x61 && buf[261] === 0x72) {
-            return {
-                ext: "tar",
-                mime: "application/x-tar"
-            };
-        }
-
-        if (buf[0] === 0x52 && buf[1] === 0x61 && buf[2] === 0x72 && buf[3] === 0x21 && buf[4] === 0x1A && buf[5] === 0x7 && (buf[6] === 0x0 || buf[6] === 0x1)) {
-            return {
-                ext: "rar",
-                mime: "application/x-rar-compressed"
-            };
-        }
-
-        if (buf[0] === 0x1F && buf[1] === 0x8B && buf[2] === 0x8) {
-            return {
-                ext: "gz",
-                mime: "application/gzip"
-            };
-        }
-
-        if (buf[0] === 0x42 && buf[1] === 0x5A && buf[2] === 0x68) {
-            return {
-                ext: "bz2",
-                mime: "application/x-bzip2"
-            };
-        }
-
-        if (buf[0] === 0x37 && buf[1] === 0x7A && buf[2] === 0xBC && buf[3] === 0xAF && buf[4] === 0x27 && buf[5] === 0x1C) {
-            return {
-                ext: "7z",
-                mime: "application/x-7z-compressed"
-            };
-        }
-
-        if (buf[0] === 0x78 && buf[1] === 0x01) {
-            return {
-                ext: "dmg, zlib",
-                mime: "application/x-apple-diskimage, application/x-deflate"
-            };
-        }
-
-        if ((buf[0] === 0x0 && buf[1] === 0x0 && buf[2] === 0x0 && (buf[3] === 0x18 || buf[3] === 0x20) && buf[4] === 0x66 && buf[5] === 0x74 && buf[6] === 0x79 && buf[7] === 0x70) || (buf[0] === 0x33 && buf[1] === 0x67 && buf[2] === 0x70 && buf[3] === 0x35) || (buf[0] === 0x0 && buf[1] === 0x0 && buf[2] === 0x0 && buf[3] === 0x1C && buf[4] === 0x66 && buf[5] === 0x74 && buf[6] === 0x79 && buf[7] === 0x70 && buf[8] === 0x6D && buf[9] === 0x70 && buf[10] === 0x34 && buf[11] === 0x32 && buf[16] === 0x6D && buf[17] === 0x70 && buf[18] === 0x34 && buf[19] === 0x31 && buf[20] === 0x6D && buf[21] === 0x70 && buf[22] === 0x34 && buf[23] === 0x32 && buf[24] === 0x69 && buf[25] === 0x73 && buf[26] === 0x6F && buf[27] === 0x6D)) {
-            return {
-                ext: "mp4",
-                mime: "video/mp4"
-            };
-        }
-
-        if ((buf[0] === 0x0 && buf[1] === 0x0 && buf[2] === 0x0 && buf[3] === 0x1C && buf[4] === 0x66 && buf[5] === 0x74 && buf[6] === 0x79 && buf[7] === 0x70 && buf[8] === 0x4D && buf[9] === 0x34 && buf[10] === 0x56)) {
-            return {
-                ext: "m4v",
-                mime: "video/x-m4v"
-            };
-        }
-
-        if (buf[0] === 0x4D && buf[1] === 0x54 && buf[2] === 0x68 && buf[3] === 0x64) {
-            return {
-                ext: "mid",
-                mime: "audio/midi"
-            };
-        }
-
-        // needs to be before the `webm` check
-        if (buf[31] === 0x6D && buf[32] === 0x61 && buf[33] === 0x74 && buf[34] === 0x72 && buf[35] === 0x6f && buf[36] === 0x73 && buf[37] === 0x6B && buf[38] === 0x61) {
-            return {
-                ext: "mkv",
-                mime: "video/x-matroska"
-            };
-        }
-
-        if (buf[0] === 0x1A && buf[1] === 0x45 && buf[2] === 0xDF && buf[3] === 0xA3) {
-            return {
-                ext: "webm",
-                mime: "video/webm"
-            };
-        }
-
-        if (buf[0] === 0x0 && buf[1] === 0x0 && buf[2] === 0x0 && buf[3] === 0x14 && buf[4] === 0x66 && buf[5] === 0x74 && buf[6] === 0x79 && buf[7] === 0x70) {
-            return {
-                ext: "mov",
-                mime: "video/quicktime"
-            };
-        }
-
-        if (buf[0] === 0x52 && buf[1] === 0x49 && buf[2] === 0x46 && buf[3] === 0x46 && buf[8] === 0x41 && buf[9] === 0x56 && buf[10] === 0x49) {
-            return {
-                ext: "avi",
-                mime: "video/x-msvideo"
-            };
-        }
-
-        if (buf[0] === 0x30 && buf[1] === 0x26 && buf[2] === 0xB2 && buf[3] === 0x75 && buf[4] === 0x8E && buf[5] === 0x66 && buf[6] === 0xCF && buf[7] === 0x11 && buf[8] === 0xA6 && buf[9] === 0xD9) {
-            return {
-                ext: "wmv",
-                mime: "video/x-ms-wmv"
-            };
-        }
-
-        if (buf[0] === 0x0 && buf[1] === 0x0 && buf[2] === 0x1 && buf[3].toString(16)[0] === "b") {
-            return {
-                ext: "mpg",
-                mime: "video/mpeg"
-            };
-        }
-
-        if ((buf[0] === 0x49 && buf[1] === 0x44 && buf[2] === 0x33) || (buf[0] === 0xFF && buf[1] === 0xfb)) {
-            return {
-                ext: "mp3",
-                mime: "audio/mpeg"
-            };
-        }
-
-        if ((buf[4] === 0x66 && buf[5] === 0x74 && buf[6] === 0x79 && buf[7] === 0x70 && buf[8] === 0x4D && buf[9] === 0x34 && buf[10] === 0x41) || (buf[0] === 0x4D && buf[1] === 0x34 && buf[2] === 0x41 && buf[3] === 0x20)) {
-            return {
-                ext: "m4a",
-                mime: "audio/m4a"
-            };
-        }
-
-        if (buf[0] === 0x4F && buf[1] === 0x67 && buf[2] === 0x67 && buf[3] === 0x53) {
-            return {
-                ext: "ogg",
-                mime: "audio/ogg"
-            };
-        }
-
-        if (buf[0] === 0x66 && buf[1] === 0x4C && buf[2] === 0x61 && buf[3] === 0x43) {
-            return {
-                ext: "flac",
-                mime: "audio/x-flac"
-            };
-        }
-
-        if (buf[0] === 0x52 && buf[1] === 0x49 && buf[2] === 0x46 && buf[3] === 0x46 && buf[8] === 0x57 && buf[9] === 0x41 && buf[10] === 0x56 && buf[11] === 0x45) {
-            return {
-                ext: "wav",
-                mime: "audio/x-wav"
-            };
-        }
-
-        if (buf[0] === 0x23 && buf[1] === 0x21 && buf[2] === 0x41 && buf[3] === 0x4D && buf[4] === 0x52 && buf[5] === 0x0A) {
-            return {
-                ext: "amr",
-                mime: "audio/amr"
-            };
-        }
-
-        if (buf[0] === 0x25 && buf[1] === 0x50 && buf[2] === 0x44 && buf[3] === 0x46) {
-            return {
-                ext: "pdf",
-                mime: "application/pdf"
-            };
-        }
-
-        if (buf[0] === 0x4D && buf[1] === 0x5A) {
-            return {
-                ext: "exe",
-                mime: "application/x-msdownload"
-            };
-        }
-
-        if ((buf[0] === 0x43 || buf[0] === 0x46) && buf[1] === 0x57 && buf[2] === 0x53) {
-            return {
-                ext: "swf",
-                mime: "application/x-shockwave-flash"
-            };
-        }
-
-        if (buf[0] === 0x7B && buf[1] === 0x5C && buf[2] === 0x72 && buf[3] === 0x74 && buf[4] === 0x66) {
-            return {
-                ext: "rtf",
-                mime: "application/rtf"
-            };
-        }
-
-        if (buf[0] === 0x77 && buf[1] === 0x4F && buf[2] === 0x46 && buf[3] === 0x46 && buf[4] === 0x00 && buf[5] === 0x01 && buf[6] === 0x00 && buf[7] === 0x00) {
-            return {
-                ext: "woff",
-                mime: "application/font-woff"
-            };
-        }
-
-        if (buf[0] === 0x77 && buf[1] === 0x4F && buf[2] === 0x46 && buf[3] === 0x32 && buf[4] === 0x00 && buf[5] === 0x01 && buf[6] === 0x00 && buf[7] === 0x00) {
-            return {
-                ext: "woff2",
-                mime: "application/font-woff"
-            };
-        }
-
-        if (buf[34] === 0x4C && buf[35] === 0x50 && ((buf[8] === 0x02 && buf[9] === 0x00 && buf[10] === 0x01) || (buf[8] === 0x01 && buf[9] === 0x00 && buf[10] === 0x00) || (buf[8] === 0x02 && buf[9] === 0x00 && buf[10] === 0x02))) {
-            return {
-                ext: "eot",
-                mime: "application/octet-stream"
-            };
-        }
-
-        if (buf[0] === 0x00 && buf[1] === 0x01 && buf[2] === 0x00 && buf[3] === 0x00 && buf[4] === 0x00) {
-            return {
-                ext: "ttf",
-                mime: "application/font-sfnt"
-            };
-        }
-
-        if (buf[0] === 0x4F && buf[1] === 0x54 && buf[2] === 0x54 && buf[3] === 0x4F && buf[4] === 0x00) {
-            return {
-                ext: "otf",
-                mime: "application/font-sfnt"
-            };
-        }
-
-        if (buf[0] === 0x00 && buf[1] === 0x00 && buf[2] === 0x01 && buf[3] === 0x00) {
-            return {
-                ext: "ico",
-                mime: "image/x-icon"
-            };
-        }
-
-        if (buf[0] === 0x46 && buf[1] === 0x4C && buf[2] === 0x56 && buf[3] === 0x01) {
-            return {
-                ext: "flv",
-                mime: "video/x-flv"
-            };
-        }
-
-        if (buf[0] === 0x25 && buf[1] === 0x21) {
-            return {
-                ext: "ps",
-                mime: "application/postscript"
-            };
-        }
-
-        if (buf[0] === 0xFD && buf[1] === 0x37 && buf[2] === 0x7A && buf[3] === 0x58 && buf[4] === 0x5A && buf[5] === 0x00) {
-            return {
-                ext: "xz",
-                mime: "application/x-xz"
-            };
-        }
-
-        if (buf[0] === 0x53 && buf[1] === 0x51 && buf[2] === 0x4C && buf[3] === 0x69) {
-            return {
-                ext: "sqlite",
-                mime: "application/x-sqlite3"
-            };
-        }
-
-        /**
-         *
-         * Added by n1474335 [n1474335@gmail.com] from here on
-         *
-         */
-        if ((buf[0] === 0x1F && buf[1] === 0x9D) || (buf[0] === 0x1F && buf[1] === 0xA0)) {
-            return {
-                ext: "z, tar.z",
-                mime: "application/x-gtar"
-            };
-        }
-
-        if (buf[0] === 0x7F && buf[1] === 0x45 && buf[2] === 0x4C && buf[3] === 0x46) {
-            return {
-                ext: "none, axf, bin, elf, o, prx, puff, so",
-                mime: "application/x-executable",
-                desc: "Executable and Linkable Format file. No standard file extension."
-            };
-        }
-
-        if (buf[0] === 0xCA && buf[1] === 0xFE && buf[2] === 0xBA && buf[3] === 0xBE) {
-            return {
-                ext: "class",
-                mime: "application/java-vm"
-            };
-        }
-
-        if (buf[0] === 0xEF && buf[1] === 0xBB && buf[2] === 0xBF) {
-            return {
-                ext: "txt",
-                mime: "text/plain",
-                desc: "UTF-8 encoded Unicode byte order mark detected, commonly but not exclusively seen in text files."
-            };
-        }
-
-        // Must be before Little-endian UTF-16 BOM
-        if (buf[0] === 0xFF && buf[1] === 0xFE && buf[2] === 0x00 && buf[3] === 0x00) {
-            return {
-                ext: "UTF32LE",
-                mime: "charset/utf32le",
-                desc: "Little-endian UTF-32 encoded Unicode byte order mark detected."
-            };
-        }
-
-        if (buf[0] === 0xFF && buf[1] === 0xFE) {
-            return {
-                ext: "UTF16LE",
-                mime: "charset/utf16le",
-                desc: "Little-endian UTF-16 encoded Unicode byte order mark detected."
-            };
-        }
-
-        if ((buf[0x8001] === 0x43 && buf[0x8002] === 0x44 && buf[0x8003] === 0x30 && buf[0x8004] === 0x30 && buf[0x8005] === 0x31) ||
-            (buf[0x8801] === 0x43 && buf[0x8802] === 0x44 && buf[0x8803] === 0x30 && buf[0x8804] === 0x30 && buf[0x8805] === 0x31) ||
-            (buf[0x9001] === 0x43 && buf[0x9002] === 0x44 && buf[0x9003] === 0x30 && buf[0x9004] === 0x30 && buf[0x9005] === 0x31)) {
-            return {
-                ext: "iso",
-                mime: "application/octet-stream",
-                desc: "ISO 9660 CD/DVD image file"
-            };
-        }
-
-        if (buf[0] === 0xD0 && buf[1] === 0xCF && buf[2] === 0x11 && buf[3] === 0xE0 && buf[4] === 0xA1 && buf[5] === 0xB1 && buf[6] === 0x1A && buf[7] === 0xE1) {
-            return {
-                ext: "doc, xls, ppt",
-                mime: "application/msword, application/vnd.ms-excel, application/vnd.ms-powerpoint",
-                desc: "Microsoft Office documents"
-            };
-        }
-
-        if (buf[0] === 0x64 && buf[1] === 0x65 && buf[2] === 0x78 && buf[3] === 0x0A && buf[4] === 0x30 && buf[5] === 0x33 && buf[6] === 0x35 && buf[7] === 0x00) {
-            return {
-                ext: "dex",
-                mime: "application/octet-stream",
-                desc: "Dalvik Executable (Android)"
-            };
-        }
-
-        if (buf[0] === 0x4B && buf[1] === 0x44 && buf[2] === 0x4D) {
-            return {
-                ext: "vmdk",
-                mime: "application/vmdk, application/x-virtualbox-vmdk"
-            };
-        }
-
-        if (buf[0] === 0x43 && buf[1] === 0x72 && buf[2] === 0x32 && buf[3] === 0x34) {
-            return {
-                ext: "crx",
-                mime: "application/crx",
-                desc: "Google Chrome extension or packaged app"
-            };
-        }
-
-        if (buf[0] === 0x78 && (buf[1] === 0x01 || buf[1] === 0x9C || buf[1] === 0xDA || buf[1] === 0x5e)) {
-            return {
-                ext: "zlib",
-                mime: "application/x-deflate"
-            };
-        }
-
-        return null;
-    }
-
 }
 
+
 /**
  * Byte frequencies of various languages generated from Wikipedia dumps taken in late 2017 and early 2018.
  * The Chi-Squared test cannot accept expected values of 0, so 0.0001 has been used to account for bytes

src/core/lib/Stream.mjs

@@ -0,0 +1,263 @@
+/**
+ * Stream class for parsing binary protocols.
+ *
+ * @author n1474335 [n1474335@gmail.com]
+ * @author tlwr [toby@toby.codes]
+ * @copyright Crown Copyright 2018
+ * @license Apache-2.0
+ *
+ */
+
+/**
+ * A Stream can be used to traverse a binary blob, interpreting sections of it
+ * as various data types.
+ */
+export default class Stream {
+
+    /**
+     * Stream constructor.
+     *
+     * @param {Uint8Array} input
+     */
+    constructor(input) {
+        this.bytes = input;
+        this.length = this.bytes.length;
+        this.position = 0;
+        this.bitPos = 0;
+    }
+
+    /**
+     * Get a number of bytes from the current position.
+     *
+     * @param {number} numBytes
+     * @returns {Uint8Array}
+     */
+    getBytes(numBytes) {
+        if (this.position > this.length) return undefined;
+
+        const newPosition = this.position + numBytes;
+        const bytes = this.bytes.slice(this.position, newPosition);
+        this.position = newPosition;
+        this.bitPos = 0;
+        return bytes;
+    }
+
+    /**
+     * Interpret the following bytes as a string, stopping at the next null byte or
+     * the supplied limit.
+     *
+     * @param {number} numBytes
+     * @returns {string}
+     */
+    readString(numBytes) {
+        if (this.position > this.length) return undefined;
+
+        let result = "";
+        for (let i = this.position; i < this.position + numBytes; i++) {
+            const currentByte = this.bytes[i];
+            if (currentByte === 0) break;
+            result += String.fromCharCode(currentByte);
+        }
+        this.position += numBytes;
+        this.bitPos = 0;
+        return result;
+    }
+
+    /**
+     * Interpret the following bytes as an integer in big or little endian.
+     *
+     * @param {number} numBytes
+     * @param {string} [endianness="be"]
+     * @returns {number}
+     */
+    readInt(numBytes, endianness="be") {
+        if (this.position > this.length) return undefined;
+
+        let val = 0;
+        if (endianness === "be") {
+            for (let i = this.position; i < this.position + numBytes; i++) {
+                val = val << 8;
+                val |= this.bytes[i];
+            }
+        } else {
+            for (let i = this.position + numBytes - 1; i >= this.position; i--) {
+                val = val << 8;
+                val |= this.bytes[i];
+            }
+        }
+        this.position += numBytes;
+        this.bitPos = 0;
+        return val;
+    }
+
+    /**
+     * Reads a number of bits from the buffer.
+     *
+     * @TODO Add endianness
+     *
+     * @param {number} numBits
+     * @returns {number}
+     */
+    readBits(numBits) {
+        if (this.position > this.length) return undefined;
+
+        let bitBuf = 0,
+            bitBufLen = 0;
+
+        // Add remaining bits from current byte
+        bitBuf = (this.bytes[this.position++] & bitMask(this.bitPos)) >>> this.bitPos;
+        bitBufLen = 8 - this.bitPos;
+        this.bitPos = 0;
+
+        // Not enough bits yet
+        while (bitBufLen < numBits) {
+            bitBuf |= this.bytes[this.position++] << bitBufLen;
+            bitBufLen += 8;
+        }
+
+        // Reverse back to numBits
+        if (bitBufLen > numBits) {
+            const excess = bitBufLen - numBits;
+            bitBuf &= (1 << numBits) - 1;
+            bitBufLen -= excess;
+            this.position--;
+            this.bitPos = 8 - excess;
+        }
+
+        return bitBuf;
+
+        /**
+         * Calculates the bit mask based on the current bit position.
+         *
+         * @param {number} bitPos
+         * @returns {number} The bit mask
+         */
+        function bitMask(bitPos) {
+            return 256 - (1 << bitPos);
+        }
+    }
+
+    /**
+     * Consume the stream until we reach the specified byte or sequence of bytes.
+     *
+     * @param {number|List<number>} val
+     */
+    continueUntil(val) {
+        if (this.position > this.length) return;
+
+        this.bitPos = 0;
+
+        if (typeof val === "number") {
+            while (++this.position < this.length && this.bytes[this.position] !== val) {
+                continue;
+            }
+            return;
+        }
+
+        // val is an array
+        let found = false;
+        while (!found && this.position < this.length) {
+            while (++this.position < this.length && this.bytes[this.position] !== val[0]) {
+                continue;
+            }
+            found = true;
+            for (let i = 1; i < val.length; i++) {
+                if (this.position + i > this.length || this.bytes[this.position + i] !== val[i])
+                    found = false;
+            }
+        }
+    }
+
+    /**
+     * Consume the next byte if it matches the supplied value.
+     *
+     * @param {number} val
+     */
+    consumeIf(val) {
+        if (this.bytes[this.position] === val) {
+            this.position++;
+            this.bitPos = 0;
+        }
+    }
+
+    /**
+     * Move forwards through the stream by the specified number of bytes.
+     *
+     * @param {number} numBytes
+     */
+    moveForwardsBy(numBytes) {
+        const pos = this.position + numBytes;
+        if (pos < 0 || pos > this.length)
+            throw new Error("Cannot move to position " + pos + " in stream. Out of bounds.");
+        this.position = pos;
+        this.bitPos = 0;
+    }
+
+    /**
+     * Move backwards through the stream by the specified number of bytes.
+     *
+     * @param {number} numBytes
+     */
+    moveBackwardsBy(numBytes) {
+        const pos = this.position - numBytes;
+        if (pos < 0 || pos > this.length)
+            throw new Error("Cannot move to position " + pos + " in stream. Out of bounds.");
+        this.position = pos;
+        this.bitPos = 0;
+    }
+
+    /**
+     * Move backwards through the strem by the specified number of bits.
+     *
+     * @param {number} numBits
+     */
+    moveBackwardsByBits(numBits) {
+        if (numBits <= this.bitPos) {
+            this.bitPos -= numBits;
+        } else {
+            if (this.bitPos > 0) {
+                numBits -= this.bitPos;
+                this.bitPos = 0;
+            }
+
+            while (numBits > 0) {
+                this.moveBackwardsBy(1);
+                this.bitPos = 8;
+                this.moveBackwardsByBits(numBits);
+                numBits -= 8;
+            }
+        }
+    }
+
+    /**
+     * Move to a specified position in the stream.
+     *
+     * @param {number} pos
+     */
+    moveTo(pos) {
+        if (pos < 0 || pos > this.length)
+            throw new Error("Cannot move to position " + pos + " in stream. Out of bounds.");
+        this.position = pos;
+        this.bitPos = 0;
+    }
+
+    /**
+     * Returns true if there are more bytes left in the stream.
+     *
+     * @returns {boolean}
+     */
+    hasMore() {
+        return this.position < this.length;
+    }
+
+    /**
+     * Returns a slice of the stream up to the current position.
+     *
+     * @returns {Uint8Array}
+     */
+    carve() {
+        if (this.bitPos > 0) this.position++;
+        return this.bytes.slice(0, this.position);
+    }
+
+}

src/core/lib/Typex.mjs

@@ -0,0 +1,227 @@
+/**
+ * Emulation of the Typex machine.
+ *
+ * @author s2224834
+ * @author The National Museum of Computing - Bombe Rebuild Project
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import OperationError from "../errors/OperationError";
+import * as Enigma from "../lib/Enigma";
+import Utils from "../Utils";
+
+/**
+ * A set of example Typex rotors. No Typex rotor wirings are publicly available, so these are
+ * randomised.
+ */
+export const ROTORS = [
+    {name: "Example 1", value: "MCYLPQUVRXGSAOWNBJEZDTFKHI<BFHNQUW"},
+    {name: "Example 2", value: "KHWENRCBISXJQGOFMAPVYZDLTU<BFHNQUW"},
+    {name: "Example 3", value: "BYPDZMGIKQCUSATREHOJNLFWXV<BFHNQUW"},
+    {name: "Example 4", value: "ZANJCGDLVHIXOBRPMSWQUKFYET<BFHNQUW"},
+    {name: "Example 5", value: "QXBGUTOVFCZPJIHSWERYNDAMLK<BFHNQUW"},
+    {name: "Example 6", value: "BDCNWUEIQVFTSXALOGZJYMHKPR<BFHNQUW"},
+    {name: "Example 7", value: "WJUKEIABMSGFTQZVCNPHORDXYL<BFHNQUW"},
+    {name: "Example 8", value: "TNVCZXDIPFWQKHSJMAOYLEURGB<BFHNQUW"},
+];
+
+/**
+ * An example Typex reflector. Again, randomised.
+ */
+export const REFLECTORS = [
+    {name: "Example", value: "AN BC FG IE KD LU MH OR TS VZ WQ XJ YP"},
+];
+
+// Special character handling on Typex keyboard
+const KEYBOARD = {
+    "Q": "1", "W": "2", "E": "3", "R": "4", "T": "5", "Y": "6", "U": "7", "I": "8", "O": "9", "P": "0",
+    "A": "-", "S": "/", "D": "Z", "F": "%", "G": "X", "H": "£", "K": "(", "L": ")",
+    "C": "V", "B": "'", "N": ",", "M": "."
+};
+const KEYBOARD_REV = {};
+for (const i of Object.keys(KEYBOARD)) {
+    KEYBOARD_REV[KEYBOARD[i]] = i;
+}
+
+/**
+ * Typex machine. A lot like the Enigma, but five rotors, of which the first two are static.
+ */
+export class TypexMachine extends Enigma.EnigmaBase {
+    /**
+     * TypexMachine constructor.
+     *
+     * @param {Object[]} rotors - List of Rotors.
+     * @param {Object} reflector - A Reflector.
+     * @param {Plugboard} plugboard - A Plugboard.
+     */
+    constructor(rotors, reflector, plugboard, keyboard) {
+        super(rotors, reflector, plugboard);
+        if (rotors.length !== 5) {
+            throw new OperationError("Typex must have 5 rotors");
+        }
+        this.keyboard = keyboard;
+    }
+
+    /**
+     * This is the same as the Enigma step function, it's just that the right-
+     * most two rotors are static.
+     */
+    step() {
+        const r0 = this.rotors[2];
+        const r1 = this.rotors[3];
+        r0.step();
+        // The second test here is the double-stepping anomaly
+        if (r0.steps.has(r0.pos) || r1.steps.has(Utils.mod(r1.pos + 1, 26))) {
+            r1.step();
+            if (r1.steps.has(r1.pos)) {
+                const r2 = this.rotors[4];
+                r2.step();
+            }
+        }
+    }
+
+    /**
+     * Encrypt/decrypt data. This is identical to the Enigma version cryptographically, but we have
+     * additional handling for the Typex's keyboard (which handles various special characters by
+     * mapping them to particular letter combinations).
+     *
+     * @param {string} input - The data to encrypt/decrypt.
+     * @return {string}
+     */
+    crypt(input) {
+        let inputMod = input;
+        if (this.keyboard === "Encrypt") {
+            inputMod = "";
+            // true = in symbol mode
+            let mode = false;
+            for (const x of input) {
+                if (x === " ") {
+                    inputMod += "X";
+                } else if (mode) {
+                    if (KEYBOARD_REV.hasOwnProperty(x)) {
+                        inputMod += KEYBOARD_REV[x];
+                    } else {
+                        mode = false;
+                        inputMod += "V" + x;
+                    }
+                } else {
+                    if (KEYBOARD_REV.hasOwnProperty(x)) {
+                        mode = true;
+                        inputMod += "Z" + KEYBOARD_REV[x];
+                    } else {
+                        inputMod += x;
+                    }
+                }
+            }
+        }
+
+        const output = super.crypt(inputMod);
+
+        let outputMod = output;
+        if (this.keyboard === "Decrypt") {
+            outputMod = "";
+            let mode = false;
+            for (const x of output) {
+                if (x === "X") {
+                    outputMod += " ";
+                } else if (x === "V") {
+                    mode = false;
+                } else if (x === "Z") {
+                    mode = true;
+                } else if (mode) {
+                    outputMod += KEYBOARD[x];
+                } else {
+                    outputMod += x;
+                }
+            }
+        }
+        return outputMod;
+    }
+}
+
+/**
+ * Typex rotor. Like an Enigma rotor, but no ring setting, and can be reversed.
+ */
+export class Rotor extends Enigma.Rotor {
+    /**
+     * Rotor constructor.
+     *
+     * @param {string} wiring - A 26 character string of the wiring order.
+     * @param {string} steps - A 0..26 character string of stepping points.
+     * @param {bool} reversed - Whether to reverse the rotor.
+     * @param {char} ringSetting - Ring setting of the rotor.
+     * @param {char} initialPosition - The initial position of the rotor.
+     */
+    constructor(wiring, steps, reversed, ringSetting, initialPos) {
+        let wiringMod = wiring;
+        if (reversed) {
+            const outMap = new Array(26);
+            for (let i=0; i<26; i++) {
+                // wiring[i] is the original output
+                // Enigma.LETTERS[i] is the original input
+                const input = Utils.mod(26 - Enigma.a2i(wiring[i]), 26);
+                const output = Enigma.i2a(Utils.mod(26 - Enigma.a2i(Enigma.LETTERS[i]), 26));
+                outMap[input] = output;
+            }
+            wiringMod = outMap.join("");
+        }
+        super(wiringMod, steps, ringSetting, initialPos);
+    }
+}
+
+/**
+ * Typex input plugboard. Based on a Rotor, because it allows arbitrary maps, not just switches
+ * like the Enigma plugboard.
+ * Not to be confused with the reflector plugboard.
+ * This is also where the Typex's backwards input wiring is implemented - it's a bit of a hack, but
+ * it means everything else continues to work like in the Enigma.
+ */
+export class Plugboard extends Enigma.Rotor {
+    /**
+     * Typex plugboard constructor.
+     *
+     * @param {string} wiring - 26 character string of mappings from A-Z, as per rotors, or "".
+     */
+    constructor(wiring) {
+        // Typex input wiring is backwards vs Enigma: that is, letters enter the rotors in a
+        // clockwise order, vs. Enigma's anticlockwise (or vice versa depending on which side
+        // you're looking at it from). I'm doing the transform here to avoid having to rewrite
+        // the Engima crypt() method in Typex as well.
+        // Note that the wiring for the reflector is the same way around as Enigma, so no
+        // transformation is necessary on that side.
+        // We're going to achieve this by mapping the plugboard settings through an additional
+        // transform that mirrors the alphabet before we pass it to the superclass.
+        if (!/^[A-Z]{26}$/.test(wiring)) {
+            throw new OperationError("Plugboard wiring must be 26 unique uppercase letters");
+        }
+        const reversed = "AZYXWVUTSRQPONMLKJIHGFEDCB";
+        wiring = wiring.replace(/./g, x => {
+            return reversed[Enigma.a2i(x)];
+        });
+        try {
+            super(wiring, "", "A", "A");
+        } catch (err) {
+            throw new OperationError(err.message.replace("Rotor", "Plugboard"));
+        }
+    }
+
+    /**
+     * Transform a character through this rotor forwards.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    transform(c) {
+        return Utils.mod(this.map[Utils.mod(c + this.pos, 26)] - this.pos, 26);
+    }
+
+    /**
+     * Transform a character through this rotor backwards.
+     *
+     * @param {number} c - The character.
+     * @returns {number}
+     */
+    revTransform(c) {
+        return Utils.mod(this.revMap[Utils.mod(c + this.pos, 26)] - this.pos, 26);
+    }
+}

src/core/operations/BlurImage.mjs

@@ -0,0 +1,102 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64";
+import jimp from "jimp";
+
+/**
+ * Blur Image operation
+ */
+class BlurImage extends Operation {
+
+    /**
+     * BlurImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Blur Image";
+        this.module = "Image";
+        this.description = "Applies a blur effect to the image.<br><br>Gaussian blur is much slower than fast blur, but produces better results.";
+        this.infoURL = "https://wikipedia.org/wiki/Gaussian_blur";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Amount",
+                type: "number",
+                value: 5,
+                min: 1
+            },
+            {
+                name: "Type",
+                type: "option",
+                value: ["Fast", "Gaussian"]
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [blurAmount, blurType] = args;
+
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            switch (blurType){
+                case "Fast":
+                    image.blur(blurAmount);
+                    break;
+                case "Gaussian":
+                    if (ENVIRONMENT_IS_WORKER())
+                        self.sendStatusMessage("Gaussian blurring image. This may take a while...");
+                    image.gaussian(blurAmount);
+                    break;
+            }
+
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error blurring image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the blurred image using HTML for web apps
+     *
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default BlurImage;

src/core/operations/ContainImage.mjs

@@ -0,0 +1,143 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Contain Image operation
+ */
+class ContainImage extends Operation {
+
+    /**
+     * ContainImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Contain Image";
+        this.module = "Image";
+        this.description = "Scales an image to the specified width and height, maintaining the aspect ratio. The image may be letterboxed.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Width",
+                type: "number",
+                value: 100,
+                min: 1
+            },
+            {
+                name: "Height",
+                type: "number",
+                value: 100,
+                min: 1
+            },
+            {
+                name: "Horizontal align",
+                type: "option",
+                value: [
+                    "Left",
+                    "Center",
+                    "Right"
+                ],
+                defaultIndex: 1
+            },
+            {
+                name: "Vertical align",
+                type: "option",
+                value: [
+                    "Top",
+                    "Middle",
+                    "Bottom"
+                ],
+                defaultIndex: 1
+            },
+            {
+                name: "Resizing algorithm",
+                type: "option",
+                value: [
+                    "Nearest Neighbour",
+                    "Bilinear",
+                    "Bicubic",
+                    "Hermite",
+                    "Bezier"
+                ],
+                defaultIndex: 1
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [width, height, hAlign, vAlign, alg] = args;
+
+        const resizeMap = {
+            "Nearest Neighbour": jimp.RESIZE_NEAREST_NEIGHBOR,
+            "Bilinear": jimp.RESIZE_BILINEAR,
+            "Bicubic": jimp.RESIZE_BICUBIC,
+            "Hermite": jimp.RESIZE_HERMITE,
+            "Bezier": jimp.RESIZE_BEZIER
+        };
+
+        const alignMap = {
+            "Left": jimp.HORIZONTAL_ALIGN_LEFT,
+            "Center": jimp.HORIZONTAL_ALIGN_CENTER,
+            "Right": jimp.HORIZONTAL_ALIGN_RIGHT,
+            "Top": jimp.VERTICAL_ALIGN_TOP,
+            "Middle": jimp.VERTICAL_ALIGN_MIDDLE,
+            "Bottom": jimp.VERTICAL_ALIGN_BOTTOM
+        };
+
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Containing image...");
+            image.contain(width, height, alignMap[hAlign] | alignMap[vAlign], resizeMap[alg]);
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error containing image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the contained image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default ContainImage;

src/core/operations/CoverImage.mjs

@@ -0,0 +1,143 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Cover Image operation
+ */
+class CoverImage extends Operation {
+
+    /**
+     * CoverImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Cover Image";
+        this.module = "Image";
+        this.description = "Scales the image to the given width and height, keeping the aspect ratio. The image may be clipped.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Width",
+                type: "number",
+                value: 100,
+                min: 1
+            },
+            {
+                name: "Height",
+                type: "number",
+                value: 100,
+                min: 1
+            },
+            {
+                name: "Horizontal align",
+                type: "option",
+                value: [
+                    "Left",
+                    "Center",
+                    "Right"
+                ],
+                defaultIndex: 1
+            },
+            {
+                name: "Vertical align",
+                type: "option",
+                value: [
+                    "Top",
+                    "Middle",
+                    "Bottom"
+                ],
+                defaultIndex: 1
+            },
+            {
+                name: "Resizing algorithm",
+                type: "option",
+                value: [
+                    "Nearest Neighbour",
+                    "Bilinear",
+                    "Bicubic",
+                    "Hermite",
+                    "Bezier"
+                ],
+                defaultIndex: 1
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [width, height, hAlign, vAlign, alg] = args;
+
+        const resizeMap = {
+            "Nearest Neighbour": jimp.RESIZE_NEAREST_NEIGHBOR,
+            "Bilinear": jimp.RESIZE_BILINEAR,
+            "Bicubic": jimp.RESIZE_BICUBIC,
+            "Hermite": jimp.RESIZE_HERMITE,
+            "Bezier": jimp.RESIZE_BEZIER
+        };
+
+        const alignMap = {
+            "Left": jimp.HORIZONTAL_ALIGN_LEFT,
+            "Center": jimp.HORIZONTAL_ALIGN_CENTER,
+            "Right": jimp.HORIZONTAL_ALIGN_RIGHT,
+            "Top": jimp.VERTICAL_ALIGN_TOP,
+            "Middle": jimp.VERTICAL_ALIGN_MIDDLE,
+            "Bottom": jimp.VERTICAL_ALIGN_BOTTOM
+        };
+
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Covering image...");
+            image.cover(width, height, alignMap[hAlign] | alignMap[vAlign], resizeMap[alg]);
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error covering image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the covered image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default CoverImage;

src/core/operations/CropImage.mjs

@@ -0,0 +1,144 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Crop Image operation
+ */
+class CropImage extends Operation {
+
+    /**
+     * CropImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Crop Image";
+        this.module = "Image";
+        this.description = "Crops an image to the specified region, or automatically crops edges.<br><br><b><u>Autocrop</u></b><br>Automatically crops same-colour borders from the image.<br><br><u>Autocrop tolerance</u><br>A percentage value for the tolerance of colour difference between pixels.<br><br><u>Only autocrop frames</u><br>Only crop real frames (all sides must have the same border)<br><br><u>Symmetric autocrop</u><br>Force autocrop to be symmetric (top/bottom and left/right are cropped by the same amount)<br><br><u>Autocrop keep border</u><br>The number of pixels of border to leave around the image.";
+        this.infoURL = "https://wikipedia.org/wiki/Cropping_(image)";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "X Position",
+                type: "number",
+                value: 0,
+                min: 0
+            },
+            {
+                name: "Y Position",
+                type: "number",
+                value: 0,
+                min: 0
+            },
+            {
+                name: "Width",
+                type: "number",
+                value: 10,
+                min: 1
+            },
+            {
+                name: "Height",
+                type: "number",
+                value: 10,
+                min: 1
+            },
+            {
+                name: "Autocrop",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "Autocrop tolerance (%)",
+                type: "number",
+                value: 0.02,
+                min: 0,
+                max: 100,
+                step: 0.01
+            },
+            {
+                name: "Only autocrop frames",
+                type: "boolean",
+                value: true
+            },
+            {
+                name: "Symmetric autocrop",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "Autocrop keep border (px)",
+                type: "number",
+                value: 0,
+                min: 0
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [xPos, yPos, width, height, autocrop, autoTolerance, autoFrames, autoSymmetric, autoBorder] = args;
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Cropping image...");
+            if (autocrop) {
+                image.autocrop({
+                    tolerance: (autoTolerance / 100),
+                    cropOnlyFrames: autoFrames,
+                    cropSymmetric: autoSymmetric,
+                    leaveBorder: autoBorder
+                });
+            } else {
+                image.crop(xPos, yPos, width, height);
+            }
+
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error cropping image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the cropped image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default CropImage;

src/core/operations/DetectFileType.mjs

@@ -5,7 +5,8 @@
  */
 
 import Operation from "../Operation";
-import Magic from "../lib/Magic";
+import {detectFileType} from "../lib/FileType";
+import {FILE_SIGNATURES} from "../lib/FileSignatures";
 
 /**
  * Detect File Type operation
@@ -24,7 +25,13 @@ class DetectFileType extends Operation {
         this.infoURL = "https://wikipedia.org/wiki/List_of_file_signatures";
         this.inputType = "ArrayBuffer";
         this.outputType = "string";
-        this.args = [];
+        this.args = Object.keys(FILE_SIGNATURES).map(cat => {
+            return {
+                name: cat,
+                type: "boolean",
+                value: true
+            };
+        });
     }
 
     /**
@@ -34,17 +41,27 @@ class DetectFileType extends Operation {
      */
     run(input, args) {
         const data = new Uint8Array(input),
-            type = Magic.magicFileType(data);
+            categories = [];
 
-        if (!type) {
+        args.forEach((cat, i) => {
+            if (cat) categories.push(Object.keys(FILE_SIGNATURES)[i]);
+        });
+
+        const types = detectFileType(data, categories);
+
+        if (!types.length) {
             return "Unknown file type. Have you tried checking the entropy of this data to determine whether it might be encrypted or compressed?";
         } else {
-            let output = "File extension: " + type.ext + "\n" +
-                "MIME type:      " + type.mime;
+            let output = "";
+
+            types.forEach(type => {
+                output += "File extension: " + type.extension + "\n" +
+                    "MIME type:      " + type.mime + "\n";
 
-            if (type.desc && type.desc.length) {
-                output += "\nDescription:    " + type.desc;
-            }
+                if (type.description && type.description.length) {
+                    output += "\nDescription:    " + type.description + "\n";
+                }
+            });
 
             return output;
         }

src/core/operations/DitherImage.mjs

@@ -0,0 +1,79 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64";
+import jimp from "jimp";
+
+/**
+ * Image Dither operation
+ */
+class DitherImage extends Operation {
+
+    /**
+     * DitherImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Dither Image";
+        this.module = "Image";
+        this.description = "Apply a dither effect to an image.";
+        this.infoURL = "https://wikipedia.org/wiki/Dither";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Applying dither to image...");
+            image.dither565();
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error applying dither to image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the dithered image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default DitherImage;

src/core/operations/Enigma.mjs

@@ -0,0 +1,214 @@
+/**
+ * Emulation of the Enigma machine.
+ *
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import {ROTORS, LETTERS, ROTORS_FOURTH, REFLECTORS, Rotor, Reflector, Plugboard, EnigmaMachine} from "../lib/Enigma";
+
+/**
+ * Enigma operation
+ */
+class Enigma extends Operation {
+    /**
+     * Enigma constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Enigma";
+        this.module = "Default";
+        this.description = "Encipher/decipher with the WW2 Enigma machine.<br><br>Enigma was used by the German military, among others, around the WW2 era as a portable cipher machine to protect sensitive military, diplomatic and commercial communications.<br><br>The standard set of German military rotors and reflectors are provided. To configure the plugboard, enter a string of connected pairs of letters, e.g. <code>AB CD EF</code> connects A to B, C to D, and E to F. This is also used to create your own reflectors. To create your own rotor, enter the letters that the rotor maps A to Z to, in order, optionally followed by <code>&lt;</code> then a list of stepping points.<br>This is deliberately fairly permissive with rotor placements etc compared to a real Enigma (on which, for example, a four-rotor Enigma uses only the thin reflectors and the beta or gamma rotor in the 4th slot).<br><br>More detailed descriptions of the Enigma, Typex and Bombe operations <a href='https://github.com/gchq/CyberChef/wiki/Enigma,-the-Bombe,-and-Typex'>can be found here</a>.";
+        this.infoURL = "https://wikipedia.org/wiki/Enigma_machine";
+        this.inputType = "string";
+        this.outputType = "string";
+        this.args = [
+            {
+                name: "Model",
+                type: "argSelector",
+                value: [
+                    {
+                        name: "3-rotor",
+                        off: [1, 2, 3]
+                    },
+                    {
+                        name: "4-rotor",
+                        on: [1, 2, 3]
+                    }
+                ]
+            },
+            {
+                name: "Left-most (4th) rotor",
+                type: "editableOption",
+                value: ROTORS_FOURTH,
+                defaultIndex: 0
+            },
+            {
+                name: "Left-most rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Left-most rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Left-hand rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 0
+            },
+            {
+                name: "Left-hand rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Left-hand rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Middle rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 1
+            },
+            {
+                name: "Middle rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Middle rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Right-hand rotor",
+                type: "editableOption",
+                value: ROTORS,
+                // Default config is the rotors I-III *left to right*
+                defaultIndex: 2
+            },
+            {
+                name: "Right-hand rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Right-hand rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Reflector",
+                type: "editableOption",
+                value: REFLECTORS
+            },
+            {
+                name: "Plugboard",
+                type: "string",
+                value: ""
+            },
+            {
+                name: "Strict output",
+                hint: "Remove non-alphabet letters and group output",
+                type: "boolean",
+                value: true
+            },
+        ];
+    }
+
+    /**
+     * Helper - for ease of use rotors are specified as a single string; this
+     * method breaks the spec string into wiring and steps parts.
+     *
+     * @param {string} rotor - Rotor specification string.
+     * @param {number} i - For error messages, the number of this rotor.
+     * @returns {string[]}
+     */
+    parseRotorStr(rotor, i) {
+        if (rotor === "") {
+            throw new OperationError(`Rotor ${i} must be provided.`);
+        }
+        if (!rotor.includes("<")) {
+            return [rotor, ""];
+        }
+        return rotor.split("<", 2);
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        const model = args[0];
+        const reflectorstr = args[13];
+        const plugboardstr = args[14];
+        const removeOther = args[15];
+        const rotors = [];
+        for (let i=0; i<4; i++) {
+            if (i === 0 && model === "3-rotor") {
+                // Skip the 4th rotor settings
+                continue;
+            }
+            const [rotorwiring, rotorsteps] = this.parseRotorStr(args[i*3 + 1], 1);
+            rotors.push(new Rotor(rotorwiring, rotorsteps, args[i*3 + 2], args[i*3 + 3]));
+        }
+        // Rotors are handled in reverse
+        rotors.reverse();
+        const reflector = new Reflector(reflectorstr);
+        const plugboard = new Plugboard(plugboardstr);
+        if (removeOther) {
+            input = input.replace(/[^A-Za-z]/g, "");
+        }
+        const enigma = new EnigmaMachine(rotors, reflector, plugboard);
+        let result = enigma.crypt(input);
+        if (removeOther) {
+            // Five character cipher groups is traditional
+            result = result.replace(/([A-Z]{5})(?!$)/g, "$1 ");
+        }
+        return result;
+    }
+
+    /**
+     * Highlight Enigma
+     * This is only possible if we're passing through non-alphabet characters.
+     *
+     * @param {Object[]} pos
+     * @param {number} pos[].start
+     * @param {number} pos[].end
+     * @param {Object[]} args
+     * @returns {Object[]} pos
+     */
+    highlight(pos, args) {
+        if (args[13] === false) {
+            return pos;
+        }
+    }
+
+    /**
+     * Highlight Enigma in reverse
+     *
+     * @param {Object[]} pos
+     * @param {number} pos[].start
+     * @param {number} pos[].end
+     * @param {Object[]} args
+     * @returns {Object[]} pos
+     */
+    highlightReverse(pos, args) {
+        if (args[13] === false) {
+            return pos;
+        }
+    }
+
+}
+
+export default Enigma;

src/core/operations/ExtractFiles.mjs

@@ -0,0 +1,100 @@
+/**
+ * @author n1474335 [n1474335@gmail.com]
+ * @copyright Crown Copyright 2018
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import Utils from "../Utils";
+import {scanForFileTypes, extractFile} from "../lib/FileType";
+import {FILE_SIGNATURES} from "../lib/FileSignatures";
+
+/**
+ * Extract Files operation
+ */
+class ExtractFiles extends Operation {
+
+    /**
+     * ExtractFiles constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Extract Files";
+        this.module = "Default";
+        this.description = "TODO";
+        this.infoURL = "https://forensicswiki.org/wiki/File_Carving";
+        this.inputType = "ArrayBuffer";
+        this.outputType = "List<File>";
+        this.presentType = "html";
+        this.args = Object.keys(FILE_SIGNATURES).map(cat => {
+            return {
+                name: cat,
+                type: "boolean",
+                value: cat === "Miscellaneous" ? false : true
+            };
+        }).concat([
+            {
+                name: "Ignore failed extractions",
+                type: "boolean",
+                value: "true"
+            }
+        ]);
+    }
+
+    /**
+     * @param {ArrayBuffer} input
+     * @param {Object[]} args
+     * @returns {List<File>}
+     */
+    run(input, args) {
+        const bytes = new Uint8Array(input),
+            categories = [],
+            ignoreFailedExtractions = args.pop(1);
+
+        args.forEach((cat, i) => {
+            if (cat) categories.push(Object.keys(FILE_SIGNATURES)[i]);
+        });
+
+        // Scan for embedded files
+        const detectedFiles = scanForFileTypes(bytes, categories);
+
+        // Extract each file that we support
+        const files = [];
+        const errors = [];
+        detectedFiles.forEach(detectedFile => {
+            try {
+                files.push(extractFile(bytes, detectedFile.fileDetails, detectedFile.offset));
+            } catch (err) {
+                if (!ignoreFailedExtractions && err.message.indexOf("No extraction algorithm available") < 0) {
+                    errors.push(
+                        `Error while attempting to extract ${detectedFile.fileDetails.name} ` +
+                        `at offset ${detectedFile.offset}:\n` +
+                        `${err.message}`
+                    );
+                }
+            }
+        });
+
+        if (errors.length) {
+            throw new OperationError(errors.join("\n\n"));
+        }
+
+        return files;
+    }
+
+
+    /**
+     * Displays the files in HTML for web apps.
+     *
+     * @param {File[]} files
+     * @returns {html}
+     */
+    async present(files) {
+        return await Utils.displayFilesAsHTML(files);
+    }
+
+}
+
+export default ExtractFiles;

src/core/operations/FlipImage.mjs

@@ -0,0 +1,94 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64";
+import jimp from "jimp";
+
+/**
+ * Flip Image operation
+ */
+class FlipImage extends Operation {
+
+    /**
+     * FlipImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Flip Image";
+        this.module = "Image";
+        this.description = "Flips an image along its X or Y axis.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Axis",
+                type: "option",
+                value: ["Horizontal", "Vertical"]
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [flipAxis] = args;
+        if (!isImage(input)) {
+            throw new OperationError("Invalid input file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Flipping image...");
+            switch (flipAxis){
+                case "Horizontal":
+                    image.flip(true, false);
+                    break;
+                case "Vertical":
+                    image.flip(false, true);
+                    break;
+            }
+
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error flipping image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the flipped image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default FlipImage;

src/core/operations/Fork.mjs

@@ -89,7 +89,7 @@ class Fork extends Operation {
         // Run recipe over each tranche
         for (i = 0; i < inputs.length; i++) {
             // Baseline ing values for each tranche so that registers are reset
-            subOpList.forEach((op, i) => {
+            recipe.opList.forEach((op, i) => {
                 op.ingValues = JSON.parse(JSON.stringify(ingValues[i]));
             });
 

src/core/operations/GenerateQRCode.mjs

@@ -8,7 +8,7 @@ import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import qr from "qr-image";
 import { toBase64 } from "../lib/Base64";
-import Magic from "../lib/Magic";
+import { isImage } from "../lib/FileType";
 import Utils from "../Utils";
 
 /**
@@ -100,9 +100,9 @@ class GenerateQRCode extends Operation {
 
         if (format === "PNG") {
             let dataURI = "data:";
-            const type = Magic.magicFileType(data);
-            if (type && type.mime.indexOf("image") === 0){
-                dataURI += type.mime + ";";
+            const mime = isImage(data);
+            if (mime){
+                dataURI += mime + ";";
             } else {
                 throw new OperationError("Invalid PNG file generated by QR image");
             }

src/core/operations/ImageBrightnessContrast.mjs

@@ -0,0 +1,103 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Image Brightness / Contrast operation
+ */
+class ImageBrightnessContrast extends Operation {
+
+    /**
+     * ImageBrightnessContrast constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Image Brightness / Contrast";
+        this.module = "Image";
+        this.description = "Adjust the brightness or contrast of an image.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Brightness",
+                type: "number",
+                value: 0,
+                min: -100,
+                max: 100
+            },
+            {
+                name: "Contrast",
+                type: "number",
+                value: 0,
+                min: -100,
+                max: 100
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [brightness, contrast] = args;
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (brightness !== 0) {
+                if (ENVIRONMENT_IS_WORKER())
+                    self.sendStatusMessage("Changing image brightness...");
+                image.brightness(brightness / 100);
+            }
+            if (contrast !== 0) {
+                if (ENVIRONMENT_IS_WORKER())
+                    self.sendStatusMessage("Changing image contrast...");
+                image.contrast(contrast / 100);
+            }
+
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error adjusting image brightness or contrast. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default ImageBrightnessContrast;

src/core/operations/ImageFilter.mjs

@@ -0,0 +1,94 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Image Filter operation
+ */
+class ImageFilter extends Operation {
+
+    /**
+     * ImageFilter constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Image Filter";
+        this.module = "Image";
+        this.description = "Applies a greyscale or sepia filter to an image.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Filter type",
+                type: "option",
+                value: [
+                    "Greyscale",
+                    "Sepia"
+                ]
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [filterType] = args;
+        if (!isImage(input)){
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Applying " + filterType.toLowerCase() + " filter to image...");
+            if (filterType === "Greyscale") {
+                image.greyscale();
+            } else {
+                image.sepia();
+            }
+
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error applying filter to image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the blurred image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default ImageFilter;

src/core/operations/ImageHueSaturationLightness.mjs

@@ -0,0 +1,129 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Image Hue/Saturation/Lightness operation
+ */
+class ImageHueSaturationLightness extends Operation {
+
+    /**
+     * ImageHueSaturationLightness constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Image Hue/Saturation/Lightness";
+        this.module = "Image";
+        this.description = "Adjusts the hue / saturation / lightness (HSL) values of an image.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Hue",
+                type: "number",
+                value: 0,
+                min: -360,
+                max: 360
+            },
+            {
+                name: "Saturation",
+                type: "number",
+                value: 0,
+                min: -100,
+                max: 100
+            },
+            {
+                name: "Lightness",
+                type: "number",
+                value: 0,
+                min: -100,
+                max: 100
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [hue, saturation, lightness] = args;
+
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (hue !== 0) {
+                if (ENVIRONMENT_IS_WORKER())
+                    self.sendStatusMessage("Changing image hue...");
+                image.colour([
+                    {
+                        apply: "hue",
+                        params: [hue]
+                    }
+                ]);
+            }
+            if (saturation !== 0) {
+                if (ENVIRONMENT_IS_WORKER())
+                    self.sendStatusMessage("Changing image saturation...");
+                image.colour([
+                    {
+                        apply: "saturate",
+                        params: [saturation]
+                    }
+                ]);
+            }
+            if (lightness !== 0) {
+                if (ENVIRONMENT_IS_WORKER())
+                    self.sendStatusMessage("Changing image lightness...");
+                image.colour([
+                    {
+                        apply: "lighten",
+                        params: [lightness]
+                    }
+                ]);
+            }
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error adjusting image hue / saturation / lightness. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+}
+
+export default ImageHueSaturationLightness;

src/core/operations/ImageOpacity.mjs

@@ -0,0 +1,89 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Image Opacity operation
+ */
+class ImageOpacity extends Operation {
+
+    /**
+     * ImageOpacity constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Image Opacity";
+        this.module = "Image";
+        this.description = "Adjust the opacity of an image.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Opacity (%)",
+                type: "number",
+                value: 100,
+                min: 0,
+                max: 100
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [opacity] = args;
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Changing image opacity...");
+            image.opacity(opacity / 100);
+
+            const imageBuffer = await image.getBufferAsync(jimp.MIME_PNG);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error changing image opacity. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default ImageOpacity;

src/core/operations/InvertImage.mjs

@@ -0,0 +1,79 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64";
+import jimp from "jimp";
+
+/**
+ * Invert Image operation
+ */
+class InvertImage extends Operation {
+
+    /**
+     * InvertImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Invert Image";
+        this.module = "Image";
+        this.description = "Invert the colours of an image.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        if (!isImage(input)) {
+            throw new OperationError("Invalid input file format.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Inverting image...");
+            image.invert();
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error inverting image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the inverted image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default InvertImage;

src/core/operations/MultipleBombe.mjs

@@ -0,0 +1,305 @@
+/**
+ * Emulation of the Bombe machine.
+ * This version carries out multiple Bombe runs to handle unknown rotor configurations.
+ *
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import {BombeMachine} from "../lib/Bombe";
+import {ROTORS, ROTORS_FOURTH, REFLECTORS, Reflector} from "../lib/Enigma";
+
+/**
+ * Convenience method for flattening the preset ROTORS object into a newline-separated string.
+ * @param {Object[]} - Preset rotors object
+ * @param {number} s - Start index
+ * @param {number} n - End index
+ * @returns {string}
+ */
+function rotorsFormat(rotors, s, n) {
+    const res = [];
+    for (const i of rotors.slice(s, n)) {
+        res.push(i.value);
+    }
+    return res.join("\n");
+}
+
+/**
+ * Combinatorics choose function
+ * @param {number} n
+ * @param {number} k
+ * @returns number
+ */
+function choose(n, k) {
+    let res = 1;
+    for (let i=1; i<=k; i++) {
+        res *= (n + 1 - i) / i;
+    }
+    return res;
+}
+
+/**
+ * Bombe operation
+ */
+class MultipleBombe extends Operation {
+    /**
+     * Bombe constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Multiple Bombe";
+        this.module = "Default";
+        this.description = "Emulation of the Bombe machine used to attack Enigma. This version carries out multiple Bombe runs to handle unknown rotor configurations.<br><br>You should test your menu on the single Bombe operation before running it here. See the description of the Bombe operation for instructions on choosing a crib.<br><br>More detailed descriptions of the Enigma, Typex and Bombe operations <a href='https://github.com/gchq/CyberChef/wiki/Enigma,-the-Bombe,-and-Typex'>can be found here</a>.";
+        this.infoURL = "https://wikipedia.org/wiki/Bombe";
+        this.inputType = "string";
+        this.outputType = "JSON";
+        this.presentType = "html";
+        this.args = [
+            {
+                "name": "Standard Enigmas",
+                "type": "populateMultiOption",
+                "value": [
+                    {
+                        name: "German Service Enigma (First - 3 rotor)",
+                        value: [
+                            rotorsFormat(ROTORS, 0, 5),
+                            "",
+                            rotorsFormat(REFLECTORS, 0, 1)
+                        ]
+                    },
+                    {
+                        name: "German Service Enigma (Second - 3 rotor)",
+                        value: [
+                            rotorsFormat(ROTORS, 0, 8),
+                            "",
+                            rotorsFormat(REFLECTORS, 0, 2)
+                        ]
+                    },
+                    {
+                        name: "German Service Enigma (Third - 4 rotor)",
+                        value: [
+                            rotorsFormat(ROTORS, 0, 8),
+                            rotorsFormat(ROTORS_FOURTH, 1, 2),
+                            rotorsFormat(REFLECTORS, 2, 3)
+                        ]
+                    },
+                    {
+                        name: "German Service Enigma (Fourth - 4 rotor)",
+                        value: [
+                            rotorsFormat(ROTORS, 0, 8),
+                            rotorsFormat(ROTORS_FOURTH, 1, 3),
+                            rotorsFormat(REFLECTORS, 2, 4)
+                        ]
+                    },
+                    {
+                        name: "User defined",
+                        value: ["", "", ""]
+                    },
+                ],
+                "target": [1, 2, 3]
+            },
+            {
+                name: "Main rotors",
+                type: "text",
+                value: ""
+            },
+            {
+                name: "4th rotor",
+                type: "text",
+                value: ""
+            },
+            {
+                name: "Reflectors",
+                type: "text",
+                value: ""
+            },
+            {
+                name: "Crib",
+                type: "string",
+                value: ""
+            },
+            {
+                name: "Crib offset",
+                type: "number",
+                value: 0
+            },
+            {
+                name: "Use checking machine",
+                type: "boolean",
+                value: true
+            }
+        ];
+    }
+
+    /**
+     * Format and send a status update message.
+     * @param {number} nLoops - Number of loops in the menu
+     * @param {number} nStops - How many stops so far
+     * @param {number} progress - Progress (as a float in the range 0..1)
+     */
+    updateStatus(nLoops, nStops, progress, start) {
+        const elapsed = new Date().getTime() - start;
+        const remaining = (elapsed / progress) * (1 - progress) / 1000;
+        const hours = Math.floor(remaining / 3600);
+        const minutes = `0${Math.floor((remaining % 3600) / 60)}`.slice(-2);
+        const seconds = `0${Math.floor(remaining % 60)}`.slice(-2);
+        const msg = `Bombe run with ${nLoops} loop${nLoops === 1 ? "" : "s"} in menu (2+ desirable): ${nStops} stops, ${Math.floor(100 * progress)}% done, ${hours}:${minutes}:${seconds} remaining`;
+        self.sendStatusMessage(msg);
+    }
+
+    /**
+     * Early rotor description string validation.
+     * Drops stepping information.
+     * @param {string} rstr - The rotor description string
+     * @returns {string} - Rotor description with stepping stripped, if any
+     */
+    validateRotor(rstr) {
+        // The Bombe doesn't take stepping into account so we'll just ignore it here
+        if (rstr.includes("<")) {
+            rstr = rstr.split("<", 2)[0];
+        }
+        // Duplicate the validation of the rotor strings here, otherwise you might get an error
+        // thrown halfway into a big Bombe run
+        if (!/^[A-Z]{26}$/.test(rstr)) {
+            throw new OperationError("Rotor wiring must be 26 unique uppercase letters");
+        }
+        if (new Set(rstr).size !== 26) {
+            throw new OperationError("Rotor wiring must be 26 unique uppercase letters");
+        }
+        return rstr;
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        const mainRotorsStr = args[1];
+        const fourthRotorsStr = args[2];
+        const reflectorsStr = args[3];
+        let crib = args[4];
+        const offset = args[5];
+        const check = args[6];
+        const rotors = [];
+        const fourthRotors = [];
+        const reflectors = [];
+        for (let rstr of mainRotorsStr.split("\n")) {
+            rstr = this.validateRotor(rstr);
+            rotors.push(rstr);
+        }
+        if (rotors.length < 3) {
+            throw new OperationError("A minimum of three rotors must be supplied");
+        }
+        if (fourthRotorsStr !== "") {
+            for (let rstr of fourthRotorsStr.split("\n")) {
+                rstr = this.validateRotor(rstr);
+                fourthRotors.push(rstr);
+            }
+        }
+        if (fourthRotors.length === 0) {
+            fourthRotors.push("");
+        }
+        for (const rstr of reflectorsStr.split("\n")) {
+            const reflector = new Reflector(rstr);
+            reflectors.push(reflector);
+        }
+        if (reflectors.length === 0) {
+            throw new OperationError("A minimum of one reflector must be supplied");
+        }
+        if (crib.length === 0) {
+            throw new OperationError("Crib cannot be empty");
+        }
+        if (offset < 0) {
+            throw new OperationError("Offset cannot be negative");
+        }
+        // For symmetry with the Enigma op, for the input we'll just remove all invalid characters
+        input = input.replace(/[^A-Za-z]/g, "").toUpperCase();
+        crib = crib.replace(/[^A-Za-z]/g, "").toUpperCase();
+        const ciphertext = input.slice(offset);
+        let update;
+        if (ENVIRONMENT_IS_WORKER()) {
+            update = this.updateStatus;
+        } else {
+            update = undefined;
+        }
+        let bombe = undefined;
+        const output = {bombeRuns: []};
+        // I could use a proper combinatorics algorithm here... but it would be more code to
+        // write one, and we don't seem to have one in our existing libraries, so massively nested
+        // for loop it is
+        const totalRuns = choose(rotors.length, 3) * 6 * fourthRotors.length * reflectors.length;
+        let nRuns = 0;
+        let nStops = 0;
+        const start = new Date().getTime();
+        for (const rotor1 of rotors) {
+            for (const rotor2 of rotors) {
+                if (rotor2 === rotor1) {
+                    continue;
+                }
+                for (const rotor3 of rotors) {
+                    if (rotor3 === rotor2 || rotor3 === rotor1) {
+                        continue;
+                    }
+                    for (const rotor4 of fourthRotors) {
+                        for (const reflector of reflectors) {
+                            nRuns++;
+                            const runRotors = [rotor1, rotor2, rotor3];
+                            if (rotor4 !== "") {
+                                runRotors.push(rotor4);
+                            }
+                            if (bombe === undefined) {
+                                bombe = new BombeMachine(runRotors, reflector, ciphertext, crib, check);
+                                output.nLoops = bombe.nLoops;
+                            } else {
+                                bombe.changeRotors(runRotors, reflector);
+                            }
+                            const result = bombe.run();
+                            nStops += result.length;
+                            if (update !== undefined) {
+                                update(bombe.nLoops, nStops, nRuns / totalRuns, start);
+                            }
+                            if (result.length > 0) {
+                                output.bombeRuns.push({
+                                    rotors: runRotors,
+                                    reflector: reflector.pairs,
+                                    result: result
+                                });
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        return output;
+    }
+
+
+    /**
+     * Displays the MultiBombe results in an HTML table
+     *
+     * @param {Object} output
+     * @param {number} output.nLoops
+     * @param {Array[]} output.result
+     * @returns {html}
+     */
+    present(output) {
+        let html = `Bombe run on menu with ${output.nLoops} loop${output.nLoops === 1 ? "" : "s"} (2+ desirable). Note: Rotors and rotor positions are listed left to right, ignore stepping and the ring setting, and positions start at the beginning of the crib. Some plugboard settings are determined. A decryption preview starting at the beginning of the crib and ignoring stepping is also provided.\n`;
+
+        for (const run of output.bombeRuns) {
+            html += `\nRotors: ${run.rotors.slice().reverse().join(", ")}\nReflector: ${run.reflector}\n`;
+            html += "<table class='table table-hover table-sm table-bordered table-nonfluid'><tr><th>Rotor stops</th>  <th>Partial plugboard</th>  <th>Decryption preview</th></tr>\n";
+            for (const [setting, stecker, decrypt] of run.result) {
+                html += `<tr><td>${setting}</td>  <td>${stecker}</td>  <td>${decrypt}</td></tr>\n`;
+            }
+            html += "</table>\n";
+        }
+        return html;
+    }
+}
+
+export default MultipleBombe;

src/core/operations/NormaliseImage.mjs

@@ -0,0 +1,70 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64";
+import jimp from "jimp";
+
+/**
+ * Normalise Image operation
+ */
+class NormaliseImage extends Operation {
+
+    /**
+     * NormaliseImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Normalise Image";
+        this.module = "Image";
+        this.description = "Normalise the image colours.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType=  "html";
+        this.args = [];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        const image = await jimp.read(Buffer.from(input));
+
+        image.normalize();
+
+        const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+        return [...imageBuffer];
+    }
+
+    /**
+     * Displays the normalised image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default NormaliseImage;

src/core/operations/ParseQRCode.mjs

@@ -6,7 +6,7 @@
 
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
-import Magic from "../lib/Magic";
+import { isImage } from "../lib/FileType";
 import jsqr from "jsqr";
 import jimp from "jimp";
 
@@ -42,64 +42,61 @@ class ParseQRCode extends Operation {
      * @returns {string}
      */
     async run(input, args) {
-        const type = Magic.magicFileType(input);
         const [normalise] = args;
 
         // Make sure that the input is an image
-        if (type && type.mime.indexOf("image") === 0) {
-            let image = input;
+        if (!isImage(input)) throw new OperationError("Invalid file type.");
 
-            if (normalise) {
-                // Process the image to be easier to read by jsqr
-                // Disables the alpha channel
-                // Sets the image default background to white
-                // Normalises the image colours
-                // Makes the image greyscale
-                // Converts image to a JPEG
-                image = await new Promise((resolve, reject) => {
-                    jimp.read(Buffer.from(input))
-                        .then(image => {
-                            image
-                                .rgba(false)
-                                .background(0xFFFFFFFF)
-                                .normalize()
-                                .greyscale()
-                                .getBuffer(jimp.MIME_JPEG, (error, result) => {
-                                    resolve(result);
-                                });
-                        })
-                        .catch(err => {
-                            reject(new OperationError("Error reading the image file."));
-                        });
-                });
-            }
-
-            if (image instanceof OperationError) {
-                throw image;
-            }
+        let image = input;
 
-            return new Promise((resolve, reject) => {
-                jimp.read(Buffer.from(image))
+        if (normalise) {
+            // Process the image to be easier to read by jsqr
+            // Disables the alpha channel
+            // Sets the image default background to white
+            // Normalises the image colours
+            // Makes the image greyscale
+            // Converts image to a JPEG
+            image = await new Promise((resolve, reject) => {
+                jimp.read(Buffer.from(input))
                     .then(image => {
-                        if (image.bitmap != null) {
-                            const qrData = jsqr(image.bitmap.data, image.getWidth(), image.getHeight());
-                            if (qrData != null) {
-                                resolve(qrData.data);
-                            } else {
-                                reject(new OperationError("Couldn't read a QR code from the image."));
-                            }
-                        } else {
-                            reject(new OperationError("Error reading the image file."));
-                        }
+                        image
+                            .rgba(false)
+                            .background(0xFFFFFFFF)
+                            .normalize()
+                            .greyscale()
+                            .getBuffer(jimp.MIME_JPEG, (error, result) => {
+                                resolve(result);
+                            });
                     })
                     .catch(err => {
                         reject(new OperationError("Error reading the image file."));
                     });
             });
-        } else {
-            throw new OperationError("Invalid file type.");
         }
 
+        if (image instanceof OperationError) {
+            throw image;
+        }
+
+        return new Promise((resolve, reject) => {
+            jimp.read(Buffer.from(image))
+                .then(image => {
+                    if (image.bitmap != null) {
+                        const qrData = jsqr(image.bitmap.data, image.getWidth(), image.getHeight());
+                        if (qrData != null) {
+                            resolve(qrData.data);
+                        } else {
+                            reject(new OperationError("Couldn't read a QR code from the image."));
+                        }
+                    } else {
+                        reject(new OperationError("Error reading the image file."));
+                    }
+                })
+                .catch(err => {
+                    reject(new OperationError("Error reading the image file."));
+                });
+        });
+
     }
 
 }

src/core/operations/PlayMedia.mjs

@@ -9,7 +9,7 @@ import { fromHex } from "../lib/Hex";
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import Utils from "../Utils";
-import Magic from "../lib/Magic";
+import { isType, detectFileType } from "../lib/FileType";
 
 /**
  * PlayMedia operation
@@ -66,8 +66,7 @@ class PlayMedia extends Operation {
 
 
         // Determine file type
-        const type = Magic.magicFileType(input);
-        if (!(type && /^audio|video/.test(type.mime))) {
+        if (!isType(/^(audio|video)/, input)) {
             throw new OperationError("Invalid or unrecognised file type");
         }
 
@@ -84,15 +83,15 @@ class PlayMedia extends Operation {
     async present(data) {
         if (!data.length) return "";
 
-        const type = Magic.magicFileType(data);
-        const matches = /^audio|video/.exec(type.mime);
+        const types = detectFileType(data);
+        const matches = /^audio|video/.exec(types[0].mime);
         if (!matches) {
             throw new OperationError("Invalid file type");
         }
-        const dataURI = `data:${type.mime};base64,${toBase64(data)}`;
+        const dataURI = `data:${types[0].mime};base64,${toBase64(data)}`;
         const element = matches[0];
 
-        let html = `<${element} src='${dataURI}' type='${type.mime}' controls>`;
+        let html = `<${element} src='${dataURI}' type='${types[0].mime}' controls>`;
         html += "<p>Unsupported media type.</p>";
         html += `</${element}>`;
         return html;

src/core/operations/RenderImage.mjs

@@ -9,7 +9,7 @@ import { fromHex } from "../lib/Hex";
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import Utils from "../Utils";
-import Magic from "../lib/Magic";
+import {isImage} from "../lib/FileType";
 
 /**
  * Render Image operation
@@ -72,8 +72,7 @@ class RenderImage extends Operation {
         }
 
         // Determine file type
-        const type = Magic.magicFileType(input);
-        if (!(type && type.mime.indexOf("image") === 0)) {
+        if (!isImage(input)) {
             throw new OperationError("Invalid file type");
         }
 
@@ -92,9 +91,9 @@ class RenderImage extends Operation {
         let dataURI = "data:";
 
         // Determine file type
-        const type = Magic.magicFileType(data);
-        if (type && type.mime.indexOf("image") === 0) {
-            dataURI += type.mime + ";";
+        const mime = isImage(data);
+        if (mime) {
+            dataURI += mime + ";";
         } else {
             throw new OperationError("Invalid file type");
         }

src/core/operations/ResizeImage.mjs

@@ -0,0 +1,138 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64.mjs";
+import jimp from "jimp";
+
+/**
+ * Resize Image operation
+ */
+class ResizeImage extends Operation {
+
+    /**
+     * ResizeImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Resize Image";
+        this.module = "Image";
+        this.description = "Resizes an image to the specified width and height values.";
+        this.infoURL = "https://wikipedia.org/wiki/Image_scaling";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Width",
+                type: "number",
+                value: 100,
+                min: 1
+            },
+            {
+                name: "Height",
+                type: "number",
+                value: 100,
+                min: 1
+            },
+            {
+                name: "Unit type",
+                type: "option",
+                value: ["Pixels", "Percent"]
+            },
+            {
+                name: "Maintain aspect ratio",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "Resizing algorithm",
+                type: "option",
+                value: [
+                    "Nearest Neighbour",
+                    "Bilinear",
+                    "Bicubic",
+                    "Hermite",
+                    "Bezier"
+                ],
+                defaultIndex: 1
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        let width = args[0],
+            height = args[1];
+        const unit = args[2],
+            aspect = args[3],
+            resizeAlg = args[4];
+
+        const resizeMap = {
+            "Nearest Neighbour": jimp.RESIZE_NEAREST_NEIGHBOR,
+            "Bilinear": jimp.RESIZE_BILINEAR,
+            "Bicubic": jimp.RESIZE_BICUBIC,
+            "Hermite": jimp.RESIZE_HERMITE,
+            "Bezier": jimp.RESIZE_BEZIER
+        };
+
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (unit === "Percent") {
+                width = image.getWidth() * (width / 100);
+                height = image.getHeight() * (height / 100);
+            }
+
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Resizing image...");
+            if (aspect) {
+                image.scaleToFit(width, height, resizeMap[resizeAlg]);
+            } else {
+                image.resize(width, height, resizeMap[resizeAlg]);
+            }
+
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error resizing image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the resized image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default ResizeImage;

src/core/operations/RotateImage.mjs

@@ -0,0 +1,87 @@
+/**
+ * @author j433866 [j433866@gmail.com]
+ * @copyright Crown Copyright 2018
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import { isImage } from "../lib/FileType";
+import { toBase64 } from "../lib/Base64";
+import jimp from "jimp";
+
+/**
+ * Rotate Image operation
+ */
+class RotateImage extends Operation {
+
+    /**
+     * RotateImage constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Rotate Image";
+        this.module = "Image";
+        this.description = "Rotates an image by the specified number of degrees.";
+        this.infoURL = "";
+        this.inputType = "byteArray";
+        this.outputType = "byteArray";
+        this.presentType = "html";
+        this.args = [
+            {
+                name: "Rotation amount (degrees)",
+                type: "number",
+                value: 90
+            }
+        ];
+    }
+
+    /**
+     * @param {byteArray} input
+     * @param {Object[]} args
+     * @returns {byteArray}
+     */
+    async run(input, args) {
+        const [degrees] = args;
+
+        if (!isImage(input)) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        let image;
+        try {
+            image = await jimp.read(Buffer.from(input));
+        } catch (err) {
+            throw new OperationError(`Error loading image. (${err})`);
+        }
+        try {
+            if (ENVIRONMENT_IS_WORKER())
+                self.sendStatusMessage("Rotating image...");
+            image.rotate(degrees);
+            const imageBuffer = await image.getBufferAsync(jimp.AUTO);
+            return [...imageBuffer];
+        } catch (err) {
+            throw new OperationError(`Error rotating image. (${err})`);
+        }
+    }
+
+    /**
+     * Displays the rotated image using HTML for web apps
+     * @param {byteArray} data
+     * @returns {html}
+     */
+    present(data) {
+        if (!data.length) return "";
+
+        const type = isImage(data);
+        if (!type) {
+            throw new OperationError("Invalid file type.");
+        }
+
+        return `<img src="data:${type};base64,${toBase64(data)}">`;
+    }
+
+}
+
+export default RotateImage;

src/core/operations/ScanForEmbeddedFiles.mjs

@@ -6,7 +6,8 @@
 
 import Operation from "../Operation";
 import Utils from "../Utils";
-import Magic from "../lib/Magic";
+import {scanForFileTypes} from "../lib/FileType";
+import {FILE_SIGNATURES} from "../lib/FileSignatures";
 
 /**
  * Scan for Embedded Files operation
@@ -25,13 +26,13 @@ class ScanForEmbeddedFiles extends Operation {
         this.infoURL = "https://wikipedia.org/wiki/List_of_file_signatures";
         this.inputType = "ArrayBuffer";
         this.outputType = "string";
-        this.args = [
-            {
-                "name": "Ignore common byte sequences",
-                "type": "boolean",
-                "value": true
-            }
-        ];
+        this.args = Object.keys(FILE_SIGNATURES).map(cat => {
+            return {
+                name: cat,
+                type: "boolean",
+                value: cat === "Miscellaneous" ? false : true
+            };
+        });
     }
 
     /**
@@ -41,43 +42,33 @@ class ScanForEmbeddedFiles extends Operation {
      */
     run(input, args) {
         let output = "Scanning data for 'magic bytes' which may indicate embedded files. The following results may be false positives and should not be treat as reliable. Any suffiently long file is likely to contain these magic bytes coincidentally.\n",
-            type,
-            numFound = 0,
-            numCommonFound = 0;
-        const ignoreCommon = args[0],
-            commonExts = ["ico", "ttf", ""],
+            numFound = 0;
+        const categories = [],
             data = new Uint8Array(input);
 
-        for (let i = 0; i < data.length; i++) {
-            type = Magic.magicFileType(data.slice(i));
-            if (type) {
-                if (ignoreCommon && commonExts.indexOf(type.ext) > -1) {
-                    numCommonFound++;
-                    continue;
-                }
+        args.forEach((cat, i) => {
+            if (cat) categories.push(Object.keys(FILE_SIGNATURES)[i]);
+        });
+
+        const types = scanForFileTypes(data, categories);
+
+        if (types.length) {
+            types.forEach(type => {
                 numFound++;
-                output += "\nOffset " + i + " (0x" + Utils.hex(i) + "):\n" +
-                    "  File extension: " + type.ext + "\n" +
-                    "  MIME type:      " + type.mime + "\n";
+                output += "\nOffset " + type.offset + " (0x" + Utils.hex(type.offset) + "):\n" +
+                    "  File extension: " + type.fileDetails.extension + "\n" +
+                    "  MIME type:      " + type.fileDetails.mime + "\n";
 
-                if (type.desc && type.desc.length) {
-                    output += "  Description:    " + type.desc + "\n";
+                if (type.fileDetails.description && type.fileDetails.description.length) {
+                    output += "  Description:    " + type.fileDetails.description + "\n";
                 }
-            }
+            });
         }
 
         if (numFound === 0) {
             output += "\nNo embedded files were found.";
         }
 
-        if (numCommonFound > 0) {
-            output += "\n\n" + numCommonFound;
-            output += numCommonFound === 1 ?
-                " file type was detected that has a common byte sequence. This is likely to be a false positive." :
-                " file types were detected that have common byte sequences. These are likely to be false positives.";
-            output += " Run this operation with the 'Ignore common byte sequences' option unchecked to see details.";
-        }
-
         return output;
     }
 

src/core/operations/SplitColourChannels.mjs

@@ -7,7 +7,7 @@
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import Utils from "../Utils";
-import Magic from "../lib/Magic";
+import {isImage} from "../lib/FileType";
 
 import jimp from "jimp";
 
@@ -38,56 +38,53 @@ class SplitColourChannels extends Operation {
      * @returns {List<File>}
      */
     async run(input, args) {
-        const type = Magic.magicFileType(input);
         // Make sure that the input is an image
-        if (type && type.mime.indexOf("image") === 0) {
-            const parsedImage = await jimp.read(Buffer.from(input));
+        if (!isImage(input)) throw new OperationError("Invalid file type.");
 
-            const red = new Promise(async (resolve, reject) => {
-                try {
-                    const split = parsedImage
-                        .clone()
-                        .color([
-                            {apply: "blue", params: [-255]},
-                            {apply: "green", params: [-255]}
-                        ])
-                        .getBufferAsync(jimp.MIME_PNG);
-                    resolve(new File([new Uint8Array((await split).values())], "red.png", {type: "image/png"}));
-                } catch (err) {
-                    reject(new OperationError(`Could not split red channel: ${err}`));
-                }
-            });
+        const parsedImage = await jimp.read(Buffer.from(input));
 
-            const green = new Promise(async (resolve, reject) => {
-                try {
-                    const split = parsedImage.clone()
-                        .color([
-                            {apply: "red", params: [-255]},
-                            {apply: "blue", params: [-255]},
-                        ]).getBufferAsync(jimp.MIME_PNG);
-                    resolve(new File([new Uint8Array((await split).values())], "green.png", {type: "image/png"}));
-                } catch (err) {
-                    reject(new OperationError(`Could not split green channel: ${err}`));
-                }
-            });
+        const red = new Promise(async (resolve, reject) => {
+            try {
+                const split = parsedImage
+                    .clone()
+                    .color([
+                        {apply: "blue", params: [-255]},
+                        {apply: "green", params: [-255]}
+                    ])
+                    .getBufferAsync(jimp.MIME_PNG);
+                resolve(new File([new Uint8Array((await split).values())], "red.png", {type: "image/png"}));
+            } catch (err) {
+                reject(new OperationError(`Could not split red channel: ${err}`));
+            }
+        });
 
-            const blue = new Promise(async (resolve, reject) => {
-                try {
-                    const split = parsedImage
-                        .color([
-                            {apply: "red", params: [-255]},
-                            {apply: "green", params: [-255]},
-                        ]).getBufferAsync(jimp.MIME_PNG);
-                    resolve(new File([new Uint8Array((await split).values())], "blue.png", {type: "image/png"}));
-                } catch (err) {
-                    reject(new OperationError(`Could not split blue channel: ${err}`));
-                }
-            });
+        const green = new Promise(async (resolve, reject) => {
+            try {
+                const split = parsedImage.clone()
+                    .color([
+                        {apply: "red", params: [-255]},
+                        {apply: "blue", params: [-255]},
+                    ]).getBufferAsync(jimp.MIME_PNG);
+                resolve(new File([new Uint8Array((await split).values())], "green.png", {type: "image/png"}));
+            } catch (err) {
+                reject(new OperationError(`Could not split green channel: ${err}`));
+            }
+        });
 
-            return await Promise.all([red, green, blue]);
-        } else {
-            throw new OperationError("Invalid file type.");
-        }
+        const blue = new Promise(async (resolve, reject) => {
+            try {
+                const split = parsedImage
+                    .color([
+                        {apply: "red", params: [-255]},
+                        {apply: "green", params: [-255]},
+                    ]).getBufferAsync(jimp.MIME_PNG);
+                resolve(new File([new Uint8Array((await split).values())], "blue.png", {type: "image/png"}));
+            } catch (err) {
+                reject(new OperationError(`Could not split blue channel: ${err}`));
+            }
+        });
+
+        return await Promise.all([red, green, blue]);
     }
 
     /**

src/core/operations/Subsection.mjs

@@ -116,7 +116,7 @@ class Subsection extends Operation {
                 }
 
                 // Baseline ing values for each tranche so that registers are reset
-                subOpList.forEach((op, i) => {
+                recipe.opList.forEach((op, i) => {
                     op.ingValues = JSON.parse(JSON.stringify(ingValues[i]));
                 });
 

src/core/operations/Typex.mjs

@@ -0,0 +1,250 @@
+/**
+ * Emulation of the Typex machine.
+ *
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation";
+import OperationError from "../errors/OperationError";
+import {LETTERS, Reflector} from "../lib/Enigma";
+import {ROTORS, REFLECTORS, TypexMachine, Plugboard, Rotor} from "../lib/Typex";
+
+/**
+ * Typex operation
+ */
+class Typex extends Operation {
+    /**
+     * Typex constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Typex";
+        this.module = "Default";
+        this.description = "Encipher/decipher with the WW2 Typex machine.<br><br>Typex was originally built by the British Royal Air Force prior to WW2, and is based on the Enigma machine with some improvements made, including using five rotors with more stepping points and interchangeable wiring cores. It was used across the British and Commonewealth militaries. A number of later variants were produced; here we simulate a WW2 era Mark 22 Typex with plugboards for the reflector and input. Typex rotors were changed regularly and none are public: a random example set are provided.<br><br>To configure the reflector plugboard, enter a string of connected pairs of letters in the reflector box, e.g. <code>AB CD EF</code> connects A to B, C to D, and E to F (you'll need to connect every letter). There is also an input plugboard: unlike Enigma's plugboard, it's not restricted to pairs, so it's entered like a rotor (without stepping). To create your own rotor, enter the letters that the rotor maps A to Z to, in order, optionally followed by <code>&lt;</code> then a list of stepping points.<br><br>More detailed descriptions of the Enigma, Typex and Bombe operations <a href='https://github.com/gchq/CyberChef/wiki/Enigma,-the-Bombe,-and-Typex'>can be found here</a>.";
+        this.infoURL = "https://wikipedia.org/wiki/Typex";
+        this.inputType = "string";
+        this.outputType = "string";
+        this.args = [
+            {
+                name: "1st (left-hand) rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 0
+            },
+            {
+                name: "1st rotor reversed",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "1st rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "1st rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "2nd rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 1
+            },
+            {
+                name: "2nd rotor reversed",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "2nd rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "2nd rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "3rd (middle) rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 2
+            },
+            {
+                name: "3rd rotor reversed",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "3rd rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "3rd rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "4th (static) rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 3
+            },
+            {
+                name: "4th rotor reversed",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "4th rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "4th rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "5th (right-hand, static) rotor",
+                type: "editableOption",
+                value: ROTORS,
+                defaultIndex: 4
+            },
+            {
+                name: "5th rotor reversed",
+                type: "boolean",
+                value: false
+            },
+            {
+                name: "5th rotor ring setting",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "5th rotor initial value",
+                type: "option",
+                value: LETTERS
+            },
+            {
+                name: "Reflector",
+                type: "editableOption",
+                value: REFLECTORS
+            },
+            {
+                name: "Plugboard",
+                type: "string",
+                value: ""
+            },
+            {
+                name: "Typex keyboard emulation",
+                type: "option",
+                value: ["None", "Encrypt", "Decrypt"]
+            },
+            {
+                name: "Strict output",
+                hint: "Remove non-alphabet letters and group output",
+                type: "boolean",
+                value: true
+            },
+        ];
+    }
+
+    /**
+     * Helper - for ease of use rotors are specified as a single string; this
+     * method breaks the spec string into wiring and steps parts.
+     *
+     * @param {string} rotor - Rotor specification string.
+     * @param {number} i - For error messages, the number of this rotor.
+     * @returns {string[]}
+     */
+    parseRotorStr(rotor, i) {
+        if (rotor === "") {
+            throw new OperationError(`Rotor ${i} must be provided.`);
+        }
+        if (!rotor.includes("<")) {
+            return [rotor, ""];
+        }
+        return rotor.split("<", 2);
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        const reflectorstr = args[20];
+        const plugboardstr = args[21];
+        const typexKeyboard = args[22];
+        const removeOther = args[23];
+        const rotors = [];
+        for (let i=0; i<5; i++) {
+            const [rotorwiring, rotorsteps] = this.parseRotorStr(args[i*4]);
+            rotors.push(new Rotor(rotorwiring, rotorsteps, args[i*4 + 1], args[i*4+2], args[i*4+3]));
+        }
+        // Rotors are handled in reverse
+        rotors.reverse();
+        const reflector = new Reflector(reflectorstr);
+        let plugboardstrMod = plugboardstr;
+        if (plugboardstrMod === "") {
+            plugboardstrMod = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+        }
+        const plugboard = new Plugboard(plugboardstrMod);
+        if (removeOther) {
+            if (typexKeyboard === "Encrypt") {
+                input = input.replace(/[^A-Za-z0-9 /%£()',.-]/g, "");
+            } else {
+                input = input.replace(/[^A-Za-z]/g, "");
+            }
+        }
+        const typex = new TypexMachine(rotors, reflector, plugboard, typexKeyboard);
+        let result = typex.crypt(input);
+        if (removeOther && typexKeyboard !== "Decrypt") {
+            // Five character cipher groups is traditional
+            result = result.replace(/([A-Z]{5})(?!$)/g, "$1 ");
+        }
+        return result;
+    }
+
+    /**
+     * Highlight Typex
+     * This is only possible if we're passing through non-alphabet characters.
+     *
+     * @param {Object[]} pos
+     * @param {number} pos[].start
+     * @param {number} pos[].end
+     * @param {Object[]} args
+     * @returns {Object[]} pos
+     */
+    highlight(pos, args) {
+        if (args[18] === false) {
+            return pos;
+        }
+    }
+
+    /**
+     * Highlight Typex in reverse
+     *
+     * @param {Object[]} pos
+     * @param {number} pos[].start
+     * @param {number} pos[].end
+     * @param {Object[]} args
+     * @returns {Object[]} pos
+     */
+    highlightReverse(pos, args) {
+        if (args[18] === false) {
+            return pos;
+        }
+    }
+
+}
+
+export default Typex;

src/core/operations/Untar.mjs

@@ -6,6 +6,7 @@
 
 import Operation from "../Operation";
 import Utils from "../Utils";
+import Stream from "../lib/Stream";
 
 /**
  * Untar operation
@@ -41,38 +42,6 @@ class Untar extends Operation {
      * @returns {List<File>}
      */
     run(input, args) {
-        const Stream = function(input) {
-            this.bytes = input;
-            this.position = 0;
-        };
-
-        Stream.prototype.getBytes = function(bytesToGet) {
-            const newPosition = this.position + bytesToGet;
-            const bytes = this.bytes.slice(this.position, newPosition);
-            this.position = newPosition;
-            return bytes;
-        };
-
-        Stream.prototype.readString = function(numBytes) {
-            let result = "";
-            for (let i = this.position; i < this.position + numBytes; i++) {
-                const currentByte = this.bytes[i];
-                if (currentByte === 0) break;
-                result += String.fromCharCode(currentByte);
-            }
-            this.position += numBytes;
-            return result;
-        };
-
-        Stream.prototype.readInt = function(numBytes, base) {
-            const string = this.readString(numBytes);
-            return parseInt(string, base);
-        };
-
-        Stream.prototype.hasMore = function() {
-            return this.position < this.bytes.length;
-        };
-
         const stream = new Stream(input),
             files = [];
 
@@ -85,7 +54,7 @@ class Untar extends Operation {
                 ownerUID: stream.readString(8),
                 ownerGID: stream.readString(8),
                 size: parseInt(stream.readString(12), 8), // Octal
-                lastModTime: new Date(1000 * stream.readInt(12, 8)), // Octal
+                lastModTime: new Date(1000 * parseInt(stream.readString(12), 8)), // Octal
                 checksum: stream.readString(8),
                 type: stream.readString(1),
                 linkedFileName: stream.readString(100),

src/core/operations/XPathExpression.mjs

@@ -57,7 +57,7 @@ class XPathExpression extends Operation {
 
         let nodes;
         try {
-            nodes = xpath.select(query, doc);
+            nodes = xpath.parse(query).select({ node: doc, allowAnyNamespaceForNoPrefix: true });
         } catch (err) {
             throw new OperationError(`Invalid XPath. Details:\n${err.message}.`);
         }

src/core/vendor/DisassembleX86-64.mjs

@@ -1,3 +1,31 @@
+/*-------------------------------------------------------------------------------------------------------------------------
+Created by Damian Recoskie (https://github.com/Recoskie/X86-64-Disassembler-JS) 
+  & exported for CyberChef by Matt [me@mitt.dev]
+---------------------------------------------------------------------------------------------------------------------------
+MIT License
+
+Copyright (c) 2019 Damian Recoskie
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+-------------------------------------------------------------------------------------------------------------------------*/
+
+
 /*-------------------------------------------------------------------------------------------------------------------------
 Binary byte code array.
 ---------------------------------------------------------------------------------------------------------------------------
@@ -3525,7 +3553,7 @@ export function LoadBinCode( HexStr )
 
   var len = HexStr.length;
 
-  for( var i = 0, el = 0, Sing = 0, int32 = 0; i < len; i += 8 )
+  for( var i = 0, el = 0, Sign = 0, int32 = 0; i < len; i += 8 )
   {
     //It is faster to read 8 hex digits at a time if possible.
 
@@ -3541,22 +3569,22 @@ export function LoadBinCode( HexStr )
 
     //The variable sing corrects the unusable sing bits during the 4 byte rotation algorithm.
 
-    Sing = int32;
+    Sign = int32;
 
-    //Remove the Sing bit value if active for when the number is changed to int32 during rotation.
+    //Remove the Sign bit value if active for when the number is changed to int32 during rotation.
 
     int32 ^= int32 & 0x80000000;
 
-    //Rotate the 32 bit int so that each number is put in order in the BinCode array. Add the Sing Bit positions back though each rotation.
+    //Rotate the 32 bit int so that each number is put in order in the BinCode array. Add the Sign Bit positions back though each rotation.
 
     int32 = ( int32 >> 24 ) | ( ( int32 << 8 ) & 0x7FFFFFFF );
-    BinCode[el++] = ( ( ( Sing >> 24 ) & 0x80 ) | int32 ) & 0xFF;
+    BinCode[el++] = ( ( ( Sign >> 24 ) & 0x80 ) | int32 ) & 0xFF;
     int32 = ( int32 >> 24 ) | ( ( int32 << 8 ) & 0x7FFFFFFF );
-    BinCode[el++] = ( ( ( Sing >> 16 ) & 0x80 ) | int32 ) & 0xFF;
+    BinCode[el++] = ( ( ( Sign >> 16 ) & 0x80 ) | int32 ) & 0xFF;
     int32 = ( int32 >> 24 ) | ( ( int32 << 8 ) & 0x7FFFFFFF );
-    BinCode[el++] = ( ( ( Sing >> 8 ) & 0x80 ) | int32 ) & 0xFF;
+    BinCode[el++] = ( ( ( Sign >> 8 ) & 0x80 ) | int32 ) & 0xFF;
     int32 = ( int32 >> 24 ) | ( ( int32 << 8 ) & 0x7FFFFFFF );
-    BinCode[el++] = ( ( Sing & 0x80 ) | int32 ) & 0xFF;
+    BinCode[el++] = ( ( Sign & 0x80 ) | int32 ) & 0xFF;
   }
 
   //Remove elements past the Number of bytes in HexStr because int 32 is always 4 bytes it is possible to end in an uneven number.
@@ -3581,11 +3609,10 @@ function NextByte()
 {
   //Add the current byte as hex to InstructionHex which will be displayed beside the decoded instruction.
   //After an instruction decodes InstructionHex is only added beside the instruction if ShowInstructionHex is active.
-
+  var t;
   if ( CodePos < BinCode.length ) //If not out of bounds.
   {
     //Convert current byte to String, and pad.
-    var t;
 
     ( ( t = BinCode[CodePos++].toString(16) ).length === 1) && ( t = "0" + t );
 
@@ -3947,11 +3974,11 @@ function DecodeImmediate( type, BySize, SizeSetting )
 
   var Pad32 = 0, Pad64 = 0;
 
-  //*Initialize the Sing value that is only set for Negative, or Positive Relative displacements.
+  //*Initialize the Sign value that is only set for Negative, or Positive Relative displacements.
 
-  var Sing = 0;
+  var Sign = 0;
 
-  //*Initialize the Sing Extend variable size as 0 Some Immediate numbers Sing extend.
+  //*Initialize the Sign Extend variable size as 0 Some Immediate numbers Sign extend.
 
   var Extend = 0;
 
@@ -4017,21 +4044,33 @@ function DecodeImmediate( type, BySize, SizeSetting )
 
     Pad32 = ( Math.min( BitMode, 1 ) << 2 ) + 4; Pad64 = Math.max( Math.min( BitMode, 2 ), 1 ) << 3;
 
-    //Add the 32 bit section to V32.
-
-    var C64 = 0; V32 += Pos32;
-
-    //If bit mode is 16 bits only the first 16 bits are used, or if Size Attribute is 16 bit.
-
-    ( BitMode <= 0 || SizeAttrSelect <= 0 ) && ( V32 &= 0xFFFF );
-
-    //Adjust the 32 bit relative address section if it was not cropped to 16 bit's.
+    //Carry bit to 64 bit section.
+    
+    var C64 = 0;
+    
+    //Relative size.
+    
+    var n = Math.min( 0x100000000, Math.pow( 2, 4 << ( S + 1 ) ) );
+    
+    //Sign bit adjust.
+    
+    if( V32 >= ( n >> 1 ) ) { V32 -= n; }
+    
+    //Add position.
+    
+    V32 += Pos32;
+    
+    //Remove carry bit and add it to C64.
 
-    ( C64 = ( ( V32 ) > 0xFFFFFFFF ) ) && ( V32 -= 0x100000000 );
+    ( C64 = ( ( V32 ) >= 0x100000000 ) ) && ( V32 -= 0x100000000 );
+    
+    //Do not carry to 64 if address is 32, and below.
+    
+    if ( S <= 2 ) { C64 = false; }
 
-    //Add the 64 bit address section if in 64 bit mode, or higher.
+    //Add the 64 bit position plus carry.
 
-    ( BitMode >= 2 ) && ( ( V64 += Pos64 + C64 ) > 0xFFFFFFFF ) && ( V64 -= 0x100000000 );
+    ( ( V64 += Pos64 + C64 ) > 0xFFFFFFFF ) && ( V64 -= 0x100000000 );
   }
 
   /*---------------------------------------------------------------------------------------------------------------------------
@@ -4052,9 +4091,9 @@ function DecodeImmediate( type, BySize, SizeSetting )
 
     var Center = 2 * ( 1 << ( n << 3 ) - 2 );
 
-    //By default the Sing is Positive.
+    //By default the Sign is Positive.
 
-    Sing = 1;
+    Sign = 1;
 
     /*-------------------------------------------------------------------------------------------------------------------------
     Calculate the VSIB displacement size if it is a VSIB Disp8.
@@ -4074,9 +4113,9 @@ function DecodeImmediate( type, BySize, SizeSetting )
 
       V32 = Center * 2 - V32;
 
-      //The Sing is negative.
+      //The Sign is negative.
 
-      Sing = 2;
+      Sign = 2;
     }
   }
 
@@ -4110,7 +4149,7 @@ function DecodeImmediate( type, BySize, SizeSetting )
 
   //*Return the Imm.
 
-  return ( ( Sing > 0 ? ( Sing > 1 ? "-" : "+" ) : "" ) + Imm.toUpperCase() );
+  return ( ( Sign > 0 ? ( Sign > 1 ? "-" : "+" ) : "" ) + Imm.toUpperCase() );
 
 }
 

src/web/App.mjs

@@ -51,10 +51,12 @@ class App {
      */
     setup() {
         document.dispatchEvent(this.manager.appstart);
+
         this.initialiseSplitter();
         this.loadLocalStorage();
         this.populateOperationsList();
         this.manager.setup();
+        this.manager.output.saveBombe();
         this.resetLayout();
         this.setCompileMessage();
 
@@ -122,6 +124,9 @@ class App {
         // Reset attemptHighlight flag
         this.options.attemptHighlight = true;
 
+        // Remove all current indicators
+        this.manager.recipe.updateBreakpointIndicator(false);
+
         this.manager.worker.bake(
             this.getInput(),        // The user's input
             this.getRecipeConfig(), // The configuration of the recipe
@@ -474,6 +479,7 @@ class App {
             const item = this.manager.recipe.addOperation(recipeConfig[i].op);
 
             // Populate arguments
+            log.debug(`Populating arguments for ${recipeConfig[i].op}`);
             const args = item.querySelectorAll(".arg");
             for (let j = 0; j < args.length; j++) {
                 if (recipeConfig[i].args[j] === undefined) continue;
@@ -499,6 +505,8 @@ class App {
                 item.querySelector(".breakpoint").click();
             }
 
+            this.manager.recipe.triggerArgEvents(item);
+
             this.progress = 0;
         }
 

src/web/HTMLIngredient.mjs

@@ -32,6 +32,9 @@ class HTMLIngredient {
         this.defaultIndex = config.defaultIndex || 0;
         this.toggleValues = config.toggleValues;
         this.id = "ing-" + this.app.nextIngId();
+        this.min = (typeof config.min === "number") ? config.min : "";
+        this.max = (typeof config.max === "number") ? config.max : "";
+        this.step = config.step || 1;
     }
 
 
@@ -42,7 +45,7 @@ class HTMLIngredient {
      */
     toHtml() {
         let html = "",
-            i, m;
+            i, m, eventFn;
 
         switch (this.type) {
             case "string":
@@ -103,6 +106,9 @@ class HTMLIngredient {
                         id="${this.id}"
                         arg-name="${this.name}"
                         value="${this.value}"
+                        min="${this.min}"
+                        max="${this.max}"
+                        step="${this.step}"
                         ${this.disabled ? "disabled" : ""}>
                     ${this.hint ? "<span class='bmd-help'>" + this.hint + "</span>" : ""}
                 </div>`;
@@ -145,10 +151,11 @@ class HTMLIngredient {
                 </div>`;
                 break;
             case "populateOption":
+            case "populateMultiOption":
                 html += `<div class="form-group">
                     <label for="${this.id}" class="bmd-label-floating">${this.name}</label>
                     <select
-                        class="form-control arg"
+                        class="form-control arg no-state-change populate-option"
                         id="${this.id}"
                         arg-name="${this.name}"
                         ${this.disabled ? "disabled" : ""}>`;
@@ -158,14 +165,20 @@ class HTMLIngredient {
                     } else if ((m = this.value[i].name.match(/\[\/([a-z0-9 -()^]+)\]/i))) {
                         html += "</optgroup>";
                     } else {
-                        html += `<option populate-value="${Utils.escapeHtml(this.value[i].value)}">${this.value[i].name}</option>`;
+                        const val = this.type === "populateMultiOption" ?
+                            JSON.stringify(this.value[i].value) :
+                            this.value[i].value;
+                        html += `<option populate-value='${Utils.escapeHtml(val)}'>${this.value[i].name}</option>`;
                     }
                 }
                 html += `</select>
                     ${this.hint ? "<span class='bmd-help'>" + this.hint + "</span>" : ""}
                 </div>`;
 
-                this.manager.addDynamicListener("#" + this.id, "change", this.populateOptionChange, this);
+                eventFn = this.type === "populateMultiOption" ?
+                    this.populateMultiOptionChange :
+                    this.populateOptionChange;
+                this.manager.addDynamicListener("#" + this.id, "change", eventFn, this);
                 break;
             case "editableOption":
                 html += `<div class="form-group input-group">
@@ -237,6 +250,27 @@ class HTMLIngredient {
                     ${this.hint ? "<span class='bmd-help'>" + this.hint + "</span>" : ""}
                 </div>`;
                 break;
+            case "argSelector":
+                html += `<div class="form-group inline">
+                    <label for="${this.id}" class="bmd-label-floating inline">${this.name}</label>
+                    <select
+                        class="form-control arg inline arg-selector"
+                        id="${this.id}"
+                        arg-name="${this.name}"
+                        ${this.disabled ? "disabled" : ""}>`;
+                for (i = 0; i < this.value.length; i++) {
+                    html += `<option ${this.defaultIndex === i ? "selected" : ""}
+                        turnon="${JSON.stringify(this.value[i].on || [])}"
+                        turnoff="${JSON.stringify(this.value[i].off || [])}">
+                            ${this.value[i].name}
+                        </option>`;
+                }
+                html += `</select>
+                    ${this.hint ? "<span class='bmd-help'>" + this.hint + "</span>" : ""}
+                </div>`;
+
+                this.manager.addDynamicListener(".arg-selector", "change", this.argSelectorChange, this);
+                break;
             default:
                 break;
         }
@@ -252,6 +286,9 @@ class HTMLIngredient {
      * @param {event} e
      */
     populateOptionChange(e) {
+        e.preventDefault();
+        e.stopPropagation();
+
         const el = e.target;
         const op = el.parentNode.parentNode;
         const target = op.querySelectorAll(".arg")[this.target];
@@ -264,6 +301,37 @@ class HTMLIngredient {
     }
 
 
+    /**
+     * Handler for populate multi option changes.
+     * Populates the relevant arguments with the specified values.
+     *
+     * @param {event} e
+     */
+    populateMultiOptionChange(e) {
+        e.preventDefault();
+        e.stopPropagation();
+
+        const el = e.target;
+        const op = el.parentNode.parentNode;
+        const args = op.querySelectorAll(".arg");
+        const targets = this.target.map(i => args[i]);
+        const vals = JSON.parse(el.childNodes[el.selectedIndex].getAttribute("populate-value"));
+        const evt = new Event("change");
+
+        for (let i = 0; i < targets.length; i++) {
+            targets[i].value = vals[i];
+        }
+
+        // Fire change event after all targets have been assigned
+        this.manager.recipe.ingChange();
+
+        // Send change event for each target once all have been assigned, to update the label placement.
+        for (const target of targets) {
+            target.dispatchEvent(evt);
+        }
+    }
+
+
     /**
      * Handler for editable option clicks.
      * Populates the input box with the selected value.
@@ -284,6 +352,33 @@ class HTMLIngredient {
         this.manager.recipe.ingChange();
     }
 
+
+    /**
+     * Handler for argument selector changes.
+     * Shows or hides the relevant arguments for this operation.
+     *
+     * @param {event} e
+     */
+    argSelectorChange(e) {
+        e.preventDefault();
+        e.stopPropagation();
+
+        const option = e.target.options[e.target.selectedIndex];
+        const op = e.target.closest(".operation");
+        const args = op.querySelectorAll(".ingredients .form-group");
+        const turnon = JSON.parse(option.getAttribute("turnon"));
+        const turnoff = JSON.parse(option.getAttribute("turnoff"));
+
+        args.forEach((arg, i) => {
+            if (turnon.includes(i)) {
+                arg.classList.remove("d-none");
+            }
+            if (turnoff.includes(i)) {
+                arg.classList.add("d-none");
+            }
+        });
+    }
+
 }
 
 export default HTMLIngredient;

src/web/Manager.mjs

@@ -173,6 +173,7 @@ class Manager {
         this.addDynamicListener("#output-file-download", "click", this.output.downloadFile, this.output);
         this.addDynamicListener("#output-file-slice i", "click", this.output.displayFileSlice, this.output);
         document.getElementById("show-file-overlay").addEventListener("click", this.output.showFileOverlayClick.bind(this.output));
+        this.addDynamicListener(".extract-file,.extract-file i", "click", this.output.extractFileClick, this.output);
 
         // Options
         document.getElementById("options").addEventListener("click", this.options.optionsClick.bind(this.options));

src/web/OutputWaiter.mjs

@@ -336,24 +336,54 @@ class OutputWaiter {
 
 
     /**
-     * Shows or hides the loading icon.
+     * Save bombe object then remove it from the DOM so that it does not cause performance issues.
+     */
+    saveBombe() {
+        this.bombeEl = document.getElementById("bombe");
+        this.bombeEl.parentNode.removeChild(this.bombeEl);
+    }
+
+
+    /**
+     * Shows or hides the output loading screen.
+     * The animated Bombe SVG, whilst quite aesthetically pleasing, is reasonably CPU
+     * intensive, so we remove it from the DOM when not in use. We only show it if the
+     * recipe is taking longer than 200ms. We add it to the DOM just before that so that
+     * it is ready to fade in without stuttering.
      *
-     * @param {boolean} value
+     * @param {boolean} value - true == show loader
      */
     toggleLoader(value) {
+        clearTimeout(this.appendBombeTimeout);
+        clearTimeout(this.outputLoaderTimeout);
+
         const outputLoader = document.getElementById("output-loader"),
-            outputElement = document.getElementById("output-text");
+            outputElement = document.getElementById("output-text"),
+            animation = document.getElementById("output-loader-animation");
 
         if (value) {
             this.manager.controls.hideStaleIndicator();
-            this.bakingStatusTimeout = setTimeout(function() {
+
+            // Start a timer to add the Bombe to the DOM just before we make it
+            // visible so that there is no stuttering
+            this.appendBombeTimeout = setTimeout(function() {
+                animation.appendChild(this.bombeEl);
+            }.bind(this), 150);
+
+            // Show the loading screen
+            this.outputLoaderTimeout = setTimeout(function() {
                 outputElement.disabled = true;
                 outputLoader.style.visibility = "visible";
                 outputLoader.style.opacity = 1;
                 this.manager.controls.toggleBakeButtonFunction(true);
             }.bind(this), 200);
         } else {
-            clearTimeout(this.bakingStatusTimeout);
+            // Remove the Bombe from the DOM to save resources
+            this.outputLoaderTimeout = setTimeout(function () {
+                try {
+                    animation.removeChild(this.bombeEl);
+                } catch (err) {}
+            }.bind(this), 500);
             outputElement.disabled = false;
             outputLoader.style.opacity = 0;
             outputLoader.style.visibility = "hidden";
@@ -494,6 +524,24 @@ class OutputWaiter {
         magicButton.setAttribute("data-original-title", "Magic!");
     }
 
+
+    /**
+     * Handler for extract file events.
+     *
+     * @param {Event} e
+     */
+    async extractFileClick(e) {
+        e.preventDefault();
+        e.stopPropagation();
+
+        const el = e.target.nodeName === "I" ? e.target.parentNode : e.target;
+        const blobURL = el.getAttribute("blob-url");
+        const fileName = el.getAttribute("file-name");
+
+        const blob = await fetch(blobURL).then(r => r.blob());
+        this.manager.input.loadFile(new File([blob], fileName, {type: blob.type}));
+    }
+
 }
 
 export default OutputWaiter;

src/web/RecipeWaiter.mjs

@@ -205,6 +205,7 @@ class RecipeWaiter {
      * @fires Manager#statechange
      */
     ingChange(e) {
+        if (e && e.target && e.target.classList.contains("no-state-change")) return;
         window.dispatchEvent(this.manager.statechange);
     }
 
@@ -340,10 +341,11 @@ class RecipeWaiter {
     /**
      * Moves or removes the breakpoint indicator in the recipe based on the position.
      *
-     * @param {number} position
+     * @param {number|boolean} position - If boolean, turn off all indicators
      */
     updateBreakpointIndicator(position) {
         const operations = document.querySelectorAll("#rec-list li.operation");
+        if (typeof position === "boolean") position = operations.length;
         for (let i = 0; i < operations.length; i++) {
             if (i === position) {
                 operations[i].classList.add("break");
@@ -429,6 +431,23 @@ class RecipeWaiter {
     }
 
 
+    /**
+     * Triggers various change events for operation arguments that have just been initialised.
+     *
+     * @param {HTMLElement} op
+     */
+    triggerArgEvents(op) {
+        // Trigger populateOption and argSelector events
+        const triggerableOptions = op.querySelectorAll(".populate-option, .arg-selector");
+        const evt = new Event("change", {bubbles: true});
+        if (triggerableOptions.length) {
+            for (const el of triggerableOptions) {
+                el.dispatchEvent(evt);
+            }
+        }
+    }
+
+
     /**
      * Handler for operationadd events.
      *
@@ -438,6 +457,8 @@ class RecipeWaiter {
      */
     opAdd(e) {
         log.debug(`'${e.target.querySelector(".op-title").textContent}' added to recipe`);
+
+        this.triggerArgEvents(e.target);
         window.dispatchEvent(this.manager.statechange);
     }
 

src/web/html/index.html

@@ -81,7 +81,11 @@
                     if (!el.classList.contains("loading"))
                         el.classList.add("loading"); // Causes CSS transition on first message
                     el.innerHTML = msg;
-                } catch (err) {} // Ignore errors if DOM not yet ready
+                } catch (err) {
+                    // This error was likely caused by the DOM not being ready yet,
+                    // so we wait another second and then try again.
+                    setTimeout(changeLoadingMsg, 1000);
+                }
             }
 
             changeLoadingMsg();
@@ -271,7 +275,7 @@
                                     <i class="material-icons">content_copy</i>
                                 </button>
                                 <button type="button" class="btn btn-primary bmd-btn-icon" id="switch" data-toggle="tooltip" title="Move output to input">
-                                    <i class="material-icons">loop</i>
+                                    <i class="material-icons">open_in_browser</i>
                                 </button>
                                 <button type="button" class="btn btn-primary bmd-btn-icon" id="undo-switch" data-toggle="tooltip" title="Undo" disabled="disabled">
                                     <i class="material-icons">undo</i>
@@ -319,7 +323,9 @@
                                 </div>
                             </div>
                             <div id="output-loader">
-                                <div class="loader"></div>
+                                <div id="output-loader-animation">
+                                    <object id="bombe" data="<%- require('../static/images/bombe.svg') %>" width="100%" height="100%"></object>
+                                </div>
                                 <div class="loading-msg"></div>
                             </div>
                         </div>

src/web/static/images/bombe.svg

@@ -0,0 +1,261 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+    Turing-Welchman Bombe SVG animation
+
+    @author n1474335 [n1474335@gmail.com]
+    @copyright Crown Copyright 2019
+    @license Apache-2.0
+-->
+<svg version="1.2" baseProfile="tiny" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"
+    x="0px" y="0px" width="550px" height="350px" viewBox="0 0 550 350" xml:space="preserve" onload="setup(evt)">
+<script type="text/ecmascript">
+    // <![CDATA[
+    function setup(evt) {
+        const allRotors = evt.target.ownerDocument.querySelectorAll('.rotor');
+        const rotors = [];
+        const initTime = Date.now();
+        const tick = 360/26;
+        const speed = 1000; // Time for one full rotation of the fast rotor
+ 
+        for (const rotor of allRotors) {
+            const row = parseInt(rotor.classList.value.match(/row(\d)/)[1], 10);
+            const startPos = row === 2 ? tick * Math.floor(Math.random()*26) : 0;
+            const bbox = rotor.getBBox();
+            const x = bbox.width/2 + bbox.x;
+            const y = bbox.height/2 + bbox.y;
+            const wait = row === 0 ? speed/26/1.5 : row === 1 ? speed : speed*26;
+ 
+            rotor.setAttribute("transform", "rotate(" + startPos + ", " + x + ", " + y + ")");
+ 
+            rotors.push({
+                el: rotor,
+                pos: startPos,
+                x: x,
+                y: y,
+                last: initTime,
+                wait: wait
+            });
+        }
+ 
+        setInterval(function() {
+            const now = Date.now();
+            for (const rotor of rotors) {
+                if (now > (rotor.last + rotor.wait)) {
+                    const numTicks = Math.floor((now - rotor.last) / rotor.wait);
+                    rotor.pos = (rotor.pos + tick * numTicks) % 360;
+                    rotor.last = rotor.last + rotor.wait * numTicks;
+                    rotor.el.setAttribute("transform", "rotate(" + rotor.pos + ", " + rotor.x + ", " + rotor.y + ")");
+                } else {
+                    // Don't bother looking at the rest
+                    break;
+                }
+            }
+        }, speed/26/1.5 - 5);
+    }
+    // ]]>
+</script>
+<style>
+    .row0 {--primary-color: #e5d41b;}
+    .row1 {--primary-color: #be1e2d;}
+    .row2 {--primary-color: #337f24;}
+</style>
+ 
+<symbol id="rotor">
+    <g transform="scale(0.1)">
+        <circle id="casing" class="ring-color" style="fill: var(--primary-color, #be1e2d)" cx="692" cy="674" r="505"/>
+        <circle id="alphabet-ring" fill="#7a5340" cx="692" cy="674" r="477"/>
+        <circle id="face" fill="#412612" cx="692" cy="674" r="412"/>
+        <circle id="plate" fill="#F1F2F2" cx="692" cy="674" r="185"/>
+        <g id="alphabet" fill="#ffffff" font-family="sans-serif" font-size="36">
+            <text transform="matrix(0.9731 0.2303 -0.2303 0.9731 779.8848 256.5488)">Z</text>
+            <text transform="matrix(0.8903 0.4554 -0.4554 0.8903 875.2021 288.6948)">Y</text>
+            <text transform="matrix(0.7561 0.6545 -0.6545 0.7561 961.8311 343.6372)">X</text>
+            <text transform="matrix(0.5696 0.8219 -0.8219 0.5696 1033.0146 417.4619)">W</text>
+            <text transform="matrix(0.3454 0.9385 -0.9385 0.3454 1088.1104 515.4634)">V</text>
+            <text transform="matrix(0.1078 0.9942 -0.9942 0.1078 1114.4678 614.5894)">U</text>
+            <text transform="matrix(-0.1302 0.9915 -0.9915 -0.1302 1116.1533 719.1523)">T</text>
+            <text transform="matrix(-0.3623 0.9321 -0.9321 -0.3623 1093.8984 817.2373)">S</text>
+            <text transform="matrix(-0.5767 0.817 -0.817 -0.5767 1048.0635 908.9912)">R</text>
+            <text transform="matrix(-0.7588 0.6514 -0.6514 -0.7588 980.2002 988.5342)">Q</text>
+            <text transform="matrix(-0.8942 0.4476 -0.4476 -0.8942 893.3154 1050.1416)">P</text>
+            <text transform="matrix(-0.9766 0.215 -0.215 -0.9766 797.7471 1087.3965)">O</text>
+            <text transform="matrix(-0.9996 -0.0298 0.0298 -0.9996 692.0405 1100.5684)">N</text>
+            <text transform="matrix(-0.961 -0.2765 0.2765 -0.961 588.2832 1087.9443)">M</text>
+            <text transform="matrix(-0.8654 -0.5011 0.5011 -0.8654 487.3003 1048.2471)">L</text>
+            <text transform="matrix(-0.7244 -0.6894 0.6894 -0.7244 406.814 991.1895)">K</text>
+            <text transform="matrix(-0.5456 -0.838 0.838 -0.5456 339.3418 913.8809)">J</text>
+            <text transform="matrix(-0.3508 -0.9364 0.9364 -0.3508 294.3491 828.2446)">I</text>
+            <text transform="matrix(-0.1295 -0.9916 0.9916 -0.1295 270.9233 742.6519)">H</text>
+            <text transform="matrix(0.1153 -0.9933 0.9933 0.1153 266.8784 638.1958)">G</text>
+            <text transform="matrix(0.3526 -0.9358 0.9358 0.3526 288.9976 533.9849)">F</text>
+            <text transform="matrix(0.5645 -0.8255 0.8255 0.5645 333.0195 443.5317)">E</text>
+            <text transform="matrix(0.7459 -0.666 0.666 0.7459 398.4409 364.5073)">D</text>
+            <text transform="matrix(0.8853 -0.4651 0.4651 0.8853 482.4824 302.3418)">C</text>
+            <text transform="matrix(0.9716 -0.2365 0.2365 0.9716 579.1396 262.5479)">B</text>
+            <text transform="matrix(0.9999 0.0162 -0.0162 0.9999 680.5581 247.4321)">A</text>
+        </g>
+        <g id="holes">
+            <circle stroke="#C49A6C" cx="692" cy="438.782" r="40.816"/>
+            <circle stroke="#C49A6C" cx="927.219" cy="674" r="40.816"/>
+            <circle stroke="#C49A6C" cx="692" cy="909.219" r="40.816"/>
+            <circle stroke="#C49A6C" cx="456.781" cy="674" r="40.816"/>
+            <circle stroke="#C49A6C" cx="574.391" cy="470.295" r="40.816"/>
+            <circle stroke="#C49A6C" cx="895.706" cy="556.39" r="40.816"/>
+            <circle stroke="#C49A6C" cx="809.609" cy="877.706" r="40.816"/>
+            <circle stroke="#C49A6C" cx="488.295" cy="791.609" r="40.816"/>
+            <circle stroke="#C49A6C" cx="488.295" cy="556.39" r="40.816"/>
+            <circle stroke="#C49A6C" cx="809.609" cy="470.293" r="40.816"/>
+            <circle stroke="#C49A6C" cx="895.706" cy="791.609" r="40.816"/>
+            <circle stroke="#C49A6C" cx="574.391" cy="877.705" r="40.816"/>
+        </g>
+        <g id="plate-screws">
+            <g>
+                <circle fill="#BCBEC0" stroke="#808285" stroke-width="2" cx="693.223" cy="543.521" r="25.342"/>
+                <line fill="#939598" stroke="#808285" stroke-width="7" x1="693.446" y1="519.729" x2="693" y2="567.311"/>
+            </g>
+            <g>
+                <circle fill="#BCBEC0" stroke="#808285" stroke-width="2" cx="822.479" cy="675.221" r="25.342"/>
+                <line fill="#939598" stroke="#808285" stroke-width="7" x1="798.689" y1="674.999" x2="846.271" y2="675.445"/>
+            </g>
+            <g>
+                <circle fill="#BCBEC0" stroke="#808285" stroke-width="2" cx="562.605" cy="673.886" r="25.341"/>
+                <line fill="#939598" stroke="#808285" stroke-width="7" x1="538.814" y1="673.663" x2="586.396" y2="674.108"/>
+            </g>
+            <g>
+                <circle fill="#BCBEC0" stroke="#808285" stroke-width="2" cx="691.863" cy="805.587" r="25.341"/>
+                <line fill="#939598" stroke="#808285" stroke-width="7" x1="692.086" y1="781.798" x2="691.64" y2="829.379"/>
+            </g>
+        </g>
+        <path id="pin" fill-rule="evenodd" fill="#D1D3D4" stroke="#939598"
+            d="M956.275,448.71c-0.969,0.389-1.924,0.836-2.848,1.302
+            c-5.875,2.962-10.965,7.197-16.168,11.152c-5.885,4.475-11.93,8.739-17.834,13.187c-10.688,8.049-21.533,15.888-32.24,23.907
+            c-2.199,1.643-4.436,3.238-6.609,4.912c-14.525,11.139-28.867,22.534-43.559,33.452c-9.428,7.004-19.436,13.346-28.354,21.005
+            c-12.459,10.694-24.723,22.592-35.869,34.65c-5.281,5.711-10.656,11.297-16.243,16.711c-3.063,2.967-5.874,5.382-8.114,8.997
+            c-2.256,3.646-4.589,7.558-6.059,11.586c-2.757,7.565,0.999,14.189,3.413,21.241c5.533,16.161-0.56,32.288-11.42,44.675
+            c-6.989,7.974-15.39,15.932-25.247,20.16c-5.45,2.337-12.057,3.965-18.012,4.105c-6.159,0.148-11.914-1.53-17.568-3.802
+            c-5.215-2.094-14.936-7.879-20.029-3.758c-4.529,3.667-8.937,7.59-13.502,11.251c-1.359,1.088-2.961,2.043-4.15,3.33
+            c0.001,0,16.224-17.545,16.596-17.948c2.86-3.092,0.168-9.246-1.066-12.486c-2.088-5.471-3.199-10.951-4.633-16.611
+            c-1.02-4.023-1.841-8.044-1.548-12.215c0.637-9.093,3.98-19.698,8.918-27.356c6.4-9.925,16.834-18.061,27.527-22.879
+            c14.831-6.684,29.543-3.252,44.133,2.23c5.441,2.044,12.285-2.206,16.829-4.831c6.116-3.534,11.542-8.171,16.117-13.547
+            c9.109-10.707,19.505-20.119,29.089-30.368c4.945-5.288,10.229-10.295,15.316-15.45l25.586-29.884l31.963-43.979
+            c0,0,29.025-38.288,29.113-38.409c9.037-11.917,24.822-22.94,25.588-39.161c0.617-13.024-14.27-17.184-24.727-16.841
+            c-7.41,0.242-16.311,0.894-23.117,4.161c-15.1,7.248-28.342,15.616-34.676,31.979c-2.504,6.464-4.865,12.671-6.76,19.319
+            c-2.051,7.208-5.539,11.212-9.826,17.088c-10.779,14.778-24.389,24.73-40.998,32.1c-4.74,2.104-9.229,4.293-14.08,6.129
+            c-3.961,1.5-9.706,3.104-12.91,5.747c-5.948,4.907-10.334,14.214-13.357,21.205c-1.911,4.418-3.278,9.046-5.009,13.535
+            c-2.069,5.37-2.532,11.326-4.88,16.507c-1.33,2.935-1.91,5.994-4.104,8.414c-2.609,2.877-4.623,4.939-8.159,6.693
+            c-3.45,1.713-6.487,3.997-10.305,4.736c-2.717,0.528-5.277,1.418-8.023,1.794c-8.203,1.127-16.54,1.73-24.695,3.159
+            c-3.994,0.7-7.947,2.283-11.792,3.534c-5.167,1.681-10.116,5.972-14.846,8.78c-10.3,6.119-20.007,15.004-27.479,24.277
+            c-5.337,6.625-8.976,14.32-11.926,22.251c-2.169,5.833-4.357,11.754-5.061,17.977c-0.564,5.001-0.074,10.062-0.502,15.077
+            c-0.706,8.26-3.203,17.47-9.294,23.414c-5.363,5.234-14.174,10.834-21.666,12.043c-7.607,1.226-15.016,0.118-20.697-5.407
+            c-5.092-4.954-9.277-11.304-15.816-14.539c-3.873-1.917-8.116-2.357-12.351-1.588c-10.82,1.965-17.767,7.374-18.428,18.637
+            c-0.545,9.325,1.999,15.171,6.731,22.947c4.323,7.103,5.315,15.456,9.255,22.756c4.052,7.503,7.825,15.248,12.169,22.583
+            c3.05,5.156,6.832,9.664,10.749,14.176c1.717,1.978,3.554,4.901,5.732,6.378c5.639,3.827,10.784,3.305,17.032,1.951
+            c2.175-0.473,3.233,0.047,4.694,1.679c1.557,1.74,1.399,1.609,0.505,3.68c-2.732,6.329-4.573,12.085-0.1,18.199
+            c3.421,4.675,8.728,9.01,13.531,12.271c7.165,4.865,14.799,8.835,22.414,12.933c8.94,4.808,18.489,8.188,27.963,11.765
+            c6.597,2.491,11.068,7.997,17.229,11.186c6.945,3.595,13.775,1.032,19.691-3.353c5.688-4.216,9.634-9.578,10.066-16.804
+            c0.415-6.938-1.239-14.501-5.51-20.082c-4.163-5.439-10.751-8.996-13.229-15.664c-2.506-6.741-0.296-14.597,1.313-21.3
+            c1.606-6.687,3.798-12.642,9.227-17.17c5.458-4.554,12.49-7.653,19.583-8.294c7.954-0.721,15.985-0.105,23.912-1.162
+            c7.9-1.052,15.855-4.074,22.918-7.696c5.104-2.616,9.105-6.979,13.309-10.789c8.875-8.052,18.1-16.759,23.735-27.459
+            c4.125-7.834,8.521-15.675,11.016-24.222c1.154-3.962,2.098-8.083,2.316-12.204c0.424-7.886-1.686-16.176,2.564-23.391
+            c5.645-9.582,14.869-17.408,25.563-20.561c8.727-2.571,17.697-4.624,25.963-8.522c7.234-3.413,16-7.686,20.182-14.833
+            c1.822-3.116,3.109-6.775,4.361-10.158c1.752-4.719,3.648-9.389,5.4-14.108c2.082-5.625,4.016-10.898,6.887-16.146
+            c2.551-4.656,6.072-7.849,9.471-11.864c2.504-2.956,4.539-5.815,7.773-8.031c3.229-2.208,6.805-3.835,10.088-5.952
+            c3.469-2.237,6.955-4.47,10.578-6.445c4.242-2.312,8.557-3.716,13.207-4.92c10.176-2.643,19.592-6.376,26.959-14.134
+            c6.977-7.349,13.82-15.747,16.816-25.566c2.938-9.634,3.967-20.147,2.086-30.07c-0.973-5.124-2.291-11.331-5.824-15.367
+            C964.873,446.457,960.432,447.042,956.275,448.71z"/>
+        <circle id="center-nut" fill="#d1a26a" stroke="#a88e75" stroke-width="25" cx="692" cy="674" r="60"/>
+        <g id="pin-screws">
+            <circle fill="#BCBEC0" stroke="#58595B" cx="768.174" cy="545.468" r="18.485"/>
+            <line fill="#BCBEC0" stroke="#939598" stroke-width="5" x1="750.079" y1="545.298" x2="786.273" y2="545.635"/>
+            <path fill="#BCBEC0" stroke="#58595B" d="M819.834,579.439c-10.211-0.094-18.564,8.103-18.66,18.313
+                c-0.094,10.208,8.102,18.562,18.313,18.657c10.205,0.095,18.563-8.102,18.656-18.312
+                C838.24,587.889,830.041,579.535,819.834,579.439z"/>
+            <line fill="#BCBEC0" stroke="#939598" stroke-width="5" x1="819.49" y1="616.02" x2="819.826" y2="579.826"/>
+            <circle fill="#BCBEC0" stroke="#58595B" cx="626.351" cy="736.463" r="18.486"/>
+            <line fill="#BCBEC0" stroke="#939598" stroke-width="5" x1="639.026" y1="749.378" x2="613.672" y2="723.543"/>
+            <circle fill="#BCBEC0" stroke="#58595B" cx="526.668" cy="709.157" r="18.485"/>
+            <line fill="#BCBEC0" stroke="#939598" stroke-width="5" x1="526.498" y1="727.252" x2="526.837" y2="691.059"/>
+            <circle fill="#BCBEC0" stroke="#58595B" cx="654.839" cy="839.752" r="18.486"/>
+            <line fill="#BCBEC0" stroke="#939598" stroke-width="5" x1="636.744" y1="839.583" x2="672.937" y2="839.922"/>
+        </g>
+        <g id="plate-mini-screws">
+            <circle fill="#E6E7E8" stroke="#A7A9AC" cx="786.206" cy="769.987" r="15.332"/>
+            <line fill="#E6E7E8" stroke="#A7A9AC" stroke-width="5" x1="775.494" y1="780.5" x2="796.92" y2="759.472"/>
+            <circle fill="#E6E7E8" stroke="#A7A9AC" cx="599.966" cy="580.227" r="15.333"/>
+            <line fill="#E6E7E8" stroke="#A7A9AC" stroke-width="5" x1="589.254" y1="590.74" x2="610.682" y2="569.712"/>
+        </g>
+        <g id="spring">
+            <line fill="none" stroke="#808285" stroke-width="2" x1="561.307" y1="722.169" x2="534.592" y2="739.515"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="565.744" y1="726.689" x2="539.028" y2="744.034"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="570.179" y1="731.21" x2="543.465" y2="748.555"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="574.616" y1="735.73" x2="547.901" y2="753.074"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="579.052" y1="740.25" x2="552.336" y2="757.596"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="583.722" y1="745.008" x2="557.007" y2="762.354"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="588.158" y1="749.529" x2="561.443" y2="766.873"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="592.595" y1="754.047" x2="565.879" y2="771.393"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="597.03" y1="758.568" x2="570.315" y2="775.913"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="601.466" y1="763.088" x2="574.751" y2="780.434"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="605.902" y1="767.608" x2="579.188" y2="784.953"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="610.338" y1="772.128" x2="583.623" y2="789.474"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="614.775" y1="776.647" x2="588.06" y2="793.994"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="619.211" y1="781.169" x2="592.496" y2="798.513"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="623.648" y1="785.688" x2="596.933" y2="803.034"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="628.084" y1="790.209" x2="601.369" y2="807.553"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="632.52" y1="794.728" x2="605.806" y2="812.074"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="636.956" y1="799.249" x2="610.241" y2="816.593"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="641.393" y1="803.77" x2="614.678" y2="821.113"/>
+            <line fill="none" stroke="#808285" stroke-width="2" x1="645.83" y1="808.288" x2="619.114" y2="825.634"/>
+        </g>
+        <g id="face-nuts">
+            <g>
+                <polygon fill-rule="evenodd" fill="#E6E7E8" stroke="#939598" points="340.617,715.657 300.423,704.888
+                    289.653,664.693 319.077,635.27 359.271,646.04 370.041,686.233   "/>
+                <path fill="#BCBEC0" stroke="#58595B" stroke-width="3" d="M306.759,698.144
+                    c-12.516-12.755-12.326-33.236,0.428-45.752c12.752-12.516,33.234-12.324,45.75,0.431c12.516,12.75,12.324,33.233-0.428,45.748
+                    C339.755,711.087,319.275,710.895,306.759,698.144z"/>
+                <line fill="#939598" stroke="#808285" stroke-width="7" x1="351.527" y1="654.208" x2="308.171" y2="696.757"/>
+            </g>
+            <g>
+                <polygon fill-rule="evenodd" fill="#E6E7E8" stroke="#939598" points="702.77,354.86 662.576,344.091
+                    651.806,303.896 681.23,274.473 721.424,285.243 732.194,325.437  "/>
+                <path fill="#603913" stroke="#3C2415" stroke-width="3" d="M668.912,337.347c-12.516-12.755-12.325-33.236,0.428-45.752c12.752-12.516,33.235-12.324,45.75,0.431
+                    c12.516,12.75,12.324,33.233-0.428,45.748C701.909,350.29,681.428,350.098,668.912,337.347z"/>
+                <line fill="#939598" stroke="#3C2415" stroke-width="7" x1="713.68" y1="293.411" x2="670.324" y2="335.96"/>
+                <line fill="#939598" stroke="#3C2415" stroke-width="7" x1="670.324" y1="293.392" x2="713.68" y2="335.941"/>
+            </g>
+            <g>
+                <polygon fill-rule="evenodd" fill="#E6E7E8" stroke="#939598" points="702.77,1072.723 662.576,1061.953
+                    651.806,1021.759 681.23,992.335 721.424,1003.105 732.193,1043.299   "/>
+                <path fill="#603913" stroke="#3C2415" stroke-width="3" d="M668.912,1055.21c-12.516-12.756-12.325-33.236,0.428-45.752c12.752-12.516,33.235-12.324,45.75,0.431
+                    c12.516,12.75,12.324,33.233-0.428,45.747C701.909,1068.152,681.428,1067.96,668.912,1055.21z"/>
+                <line fill="#939598" stroke="#3C2415" stroke-width="7" x1="713.68" y1="1011.272" x2="670.324" y2="1053.822"/>
+                <line fill="#939598" stroke="#3C2415" stroke-width="7" x1="670.324" y1="1011.254" x2="713.68" y2="1053.804"/>
+            </g>
+            <g>
+                <polygon fill-rule="evenodd" fill="#E6E7E8" stroke="#939598" points="1038.556,715.658 1078.749,704.888
+                    1089.521,664.694 1060.097,635.27 1019.901,646.041 1009.132,686.234  "/>
+                <path fill="#BCBEC0" stroke="#58595B" stroke-width="3" d="M1072.413,698.145
+                    c12.516-12.755,12.326-33.236-0.428-45.752c-12.752-12.516-33.234-12.324-45.75,0.431c-12.516,12.75-12.324,33.233,0.428,45.748
+                    C1039.417,711.087,1059.897,710.896,1072.413,698.145z"/>
+                <line fill="#939598" stroke="#808285" stroke-width="7" x1="1027.646" y1="654.208" x2="1071.001" y2="696.757"/>
+            </g>
+        </g>
+    </g>
+</symbol>
+ 
+<g class="rotor row0"><use xlink:href="#rotor" x="0" y="0" /></g>
+<g class="rotor row0"><use xlink:href="#rotor" x="105" y="0" /></g>
+<g class="rotor row0"><use xlink:href="#rotor" x="210" y="0" /></g>
+<g class="rotor row0"><use xlink:href="#rotor" x="315" y="0" /></g>
+<g class="rotor row0"><use xlink:href="#rotor" x="420" y="0" /></g>
+<g class="rotor row1"><use xlink:href="#rotor" x="0" y="105" /></g>
+<g class="rotor row1"><use xlink:href="#rotor" x="105" y="105" /></g>
+<g class="rotor row1"><use xlink:href="#rotor" x="210" y="105" /></g>
+<g class="rotor row1"><use xlink:href="#rotor" x="315" y="105" /></g>
+<g class="rotor row1"><use xlink:href="#rotor" x="420" y="105" /></g>
+<g class="rotor row2"><use xlink:href="#rotor" x="0" y="210" /></g>
+<g class="rotor row2"><use xlink:href="#rotor" x="105" y="210" /></g>
+<g class="rotor row2"><use xlink:href="#rotor" x="210" y="210" /></g>
+<g class="rotor row2"><use xlink:href="#rotor" x="315" y="210" /></g>
+<g class="rotor row2"><use xlink:href="#rotor" x="420" y="210" /></g>
+</svg>

src/web/stylesheets/components/_pane.css

@@ -91,3 +91,7 @@
     padding-right: 6px;
     padding-left: 6px;
 }
+
+#files .card-header .float-right a:hover {
+    text-decoration: none;
+}

src/web/stylesheets/layout/_io.css

@@ -73,6 +73,30 @@
     background-color: var(--primary-background-colour);
     visibility: hidden;
     opacity: 0;
+    display: flex;
+    justify-content: center;
+    align-items: center;
+
+    transition: all 0.5s ease;
+}
+
+#output-loader-animation {
+    display: block;
+    position: absolute;
+    width: 60%;
+    height: 60%;
+    top: 10%;
+    transition: all 0.5s ease;
+}
+
+#output-loader .loading-msg {
+    opacity: 1;
+    font-family: var(--primary-font-family);
+    line-height: var(--primary-line-height);
+    color: var(--primary-font-colour);
+    left: unset;
+    top: 30%;
+    position: relative;
 
     transition: all 0.5s ease;
 }
@@ -139,16 +163,6 @@
     margin-bottom: 5px;
 }
 
-#output-loader .loading-msg {
-    opacity: 1;
-    font-family: var(--primary-font-family);
-    line-height: var(--primary-line-height);
-    color: var(--primary-font-colour);
-    top: 50%;
-
-    transition: all 0.5s ease;
-}
-
 #magic {
     opacity: 1;
     visibility: visibile;

src/web/stylesheets/preloader.css

@@ -65,8 +65,8 @@
     left: calc(50% - 200px);
     top: calc(50% + 50px);
     text-align: center;
-    margin-top: 50px;
     opacity: 0;
+    font-size: 18px;
 }
 
 .loading-msg.loading {

tests/browser/nightwatch.js

@@ -87,7 +87,7 @@ module.exports = {
         // Check output
         browser
             .useCss()
-            .waitForElementNotVisible("#stale-indicator", 500)
+            .waitForElementNotVisible("#stale-indicator", 1000)
             .expect.element("#output-text").to.have.value.that.equals("44 6f 6e 27 74 20 50 61 6e 69 63 2e");
 
         // Clear recipe

tests/operations/index.mjs

@@ -88,6 +88,10 @@ import "./tests/Media";
 import "./tests/ToFromInsensitiveRegex";
 import "./tests/YARA.mjs";
 import "./tests/ConvertCoordinateFormat";
+import "./tests/Enigma";
+import "./tests/Bombe";
+import "./tests/MultipleBombe";
+import "./tests/Typex";
 
 // Cannot test operations that use the File type yet
 //import "./tests/SplitColourChannels";

tests/operations/tests/Bombe.mjs

@@ -0,0 +1,242 @@
+/**
+ * Bombe machine tests.
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import TestRegister from "../TestRegister";
+
+TestRegister.addTests([
+    {
+        // Plugboard for this test is BO LC KE GA
+        name: "Bombe: 3 rotor (self-stecker)",
+        input: "BBYFLTHHYIJQAYBBYS",
+        expectedMatch: /<td>LGA<\/td> {2}<td>SS<\/td> {2}<td>VFISUSGTKSTMPSUNAK<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "THISISATESTMESSAGE", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        // This test produces a menu that doesn't use the first letter, which is also a good test
+        name: "Bombe: 3 rotor (other stecker)",
+        input: "JBYALIHDYNUAAVKBYM",
+        expectedMatch: /<td>LGA<\/td> {2}<td>AG<\/td> {2}<td>QFIMUMAFKMQSKMYNGW<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "THISISATESTMESSAGE", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: crib offset",
+        input: "AAABBYFLTHHYIJQAYBBYS", // first three chars here are faked
+        expectedMatch: /<td>LGA<\/td> {2}<td>SS<\/td> {2}<td>VFISUSGTKSTMPSUNAK<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "THISISATESTMESSAGE", 3, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: multiple stops",
+        input: "BBYFLTHHYIJQAYBBYS",
+        expectedMatch: /<td>LGA<\/td> {2}<td>TT<\/td> {2}<td>VFISUSGTKSTMPSUNAK<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "THISISATESTM", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: checking machine",
+        input: "BBYFLTHHYIJQAYBBYS",
+        expectedMatch: /<td>LGA<\/td> {2}<td>TT AG BO CL EK FF HH II JJ SS YY<\/td> {2}<td>THISISATESTMESSAGE<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "THISISATESTM", 0, true
+                ]
+            }
+        ]
+    },
+    // This test is a bit slow - it takes about 12s on my test hardware
+    {
+        name: "Bombe: 4 rotor",
+        input: "LUOXGJSHGEDSRDOQQX",
+        expectedMatch: /<td>LHSC<\/td> {2}<td>SS<\/td> {2}<td>HHHSSSGQUUQPKSEKWK<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "4-rotor",
+                    "LEYJVCNIXWPBQMDRTAKZGFUHOS", // Beta
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV", // B thin
+                    "THISISATESTMESSAGE", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: no crib",
+        input: "JBYALIHDYNUAAVKBYM",
+        expectedMatch: /Crib cannot be empty/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: short crib",
+        input: "JBYALIHDYNUAAVKBYM",
+        expectedMatch: /Crib is too short/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "A", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: invalid crib",
+        input: "JBYALIHDYNUAAVKBYM",
+        expectedMatch: /Invalid crib: .* in both ciphertext and crib/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "AAAAAAAA", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: long crib",
+        input: "JBYALIHDYNUAAVKBYM",
+        expectedMatch: /Crib overruns supplied ciphertext/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "CCCCCCCCCCCCCCCCCCCCCC", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: really long crib",
+        input: "BBBBBBBBBBBBBBBBBBBBBBBBBB",
+        expectedMatch: /Crib is too long/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "AAAAAAAAAAAAAAAAAAAAAAAAAA", 0, false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Bombe: negative offset",
+        input: "AAAAA",
+        expectedMatch: /Offset cannot be negative/,
+        recipeConfig: [
+            {
+                "op": "Bombe",
+                "args": [
+                    "3-rotor",
+                    "",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "BBBBB", -1, false
+                ]
+            }
+        ]
+    },
+    // Enigma tests cover validation of rotors and reflector
+]);

tests/operations/tests/Enigma.mjs

@@ -0,0 +1,565 @@
+/**
+ * Enigma machine tests.
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import TestRegister from "../TestRegister";
+
+TestRegister.addTests([
+    {
+        // Simplest test: A single keypress in the default position on a basic
+        // Enigma.
+        name: "Enigma: basic wiring",
+        input: "G",
+        expectedOutput: "P",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    // Note: start on Z because it steps when the key is pressed
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "Z", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Rotor position test: single keypress, basic rotors, random start
+        // positions, no advancement of other rotors.
+        name: "Enigma: rotor position",
+        input: "A",
+        expectedOutput: "T",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "N",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "F",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "W",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Rotor ring setting test: single keypress, basic rotors, one rotor
+        // ring offset by one, basic start position, no advancement of other
+        // rotors.
+        name: "Enigma: rotor ring setting",
+        input: "A",
+        expectedOutput: "O",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "B", "Z",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Rotor ring setting test: single keypress, basic rotors, random ring
+        // settings, basic start position, no advancement of other rotors.
+        name: "Enigma: rotor ring setting 2",
+        input: "A",
+        expectedOutput: "F",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "N", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "F", "A",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "W", "Z",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Stepping: basic configuration, enough input to cause middle rotor to
+        // step
+        name: "Enigma: stepping",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "UBDZG OWCXL TKSBT MCDLP BMUQO F",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "Z",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Ensure that we can decrypt an encrypted message.
+        name: "Enigma: reflectivity",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "Z",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            },
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "Z",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Stepping: with rotors set so we're about to trigger the double step
+        // anomaly
+        name: "Enigma: double step anomaly",
+        input: "AAAAA",
+        expectedOutput: "EQIBM",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "D",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "U",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Stepping: with rotors set so we're about to trigger the double step
+        // anomaly
+        name: "Enigma: double step anomaly 2",
+        input: "AAAA",
+        expectedOutput: "BRNC",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "E",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "U",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Stepping: with rotors set so we're about to trigger the double step
+        // anomaly
+        name: "Enigma: double step anomaly 3",
+        input: "AAAAA AAA",
+        expectedOutput: "ZEEQI BMG",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "D",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "S",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Stepping: with a ring setting
+        name: "Enigma: ring setting stepping",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "PBMFE BOUBD ZGOWC XLTKS BTXSH I",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "H", "Z",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Stepping: with a ring setting and double step
+        name: "Enigma: ring setting double step",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "TEVFK UTIIW EDWVI JPMVP GDEZS P",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "Q", "A",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "C", "D",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "H", "F",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW",
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Four-rotor Enigma, random settings, no plugboard
+        name: "Enigma: four rotor",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "GZXGX QUSUW JPWVI GVBTU DQZNZ J",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "4-rotor",
+                    "LEYJVCNIXWPBQMDRTAKZGFUHOS", "A", "X", // Beta
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "O", "E",
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "P", "F",
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "D", "Q",
+                    "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV", // B thin
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Four-rotor Enigma, different wheel set, no plugboard
+        name: "Enigma: four rotor 2",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "HZJLP IKWBZ XNCWF FIHWL EROOZ C",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "4-rotor",
+                    "FSOKANUERHMBTIYCWLQPZXVGJD", "A", "L", // Gamma
+                    "JPGVOUMFYQBENHZRDKASXLICTW<AN", "A", "J", // VI
+                    "VZBRGITYUPSDNHLXAWMJQOFECK<A", "M", "G", // V
+                    "ESOVPZJAYQUIRHXLNFTGKDCMWB<K", "W", "U", // IV
+                    "AR BD CO EJ FN GT HK IV LM PW QZ SX UY", // C thin
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        // Four-rotor Enigma, different wheel set, random plugboard
+        name: "Enigma: plugboard",
+        input: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        expectedOutput: "GHLIM OJIUW DKLWM JGNJK DYJVD K",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "4-rotor",
+                    "FSOKANUERHMBTIYCWLQPZXVGJD", "A", "I", // Gamma
+                    "NZJHGRCXMYSWBOUFAIVLPEKQDT<AN", "I", "V", // VII
+                    "ESOVPZJAYQUIRHXLNFTGKDCMWB<K", "O", "O", // IV
+                    "FKQHTLXOCBJSPDZRAMEWNIUYGV<AN", "U", "Z", // VIII
+                    "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV", // B thin
+                    "WN MJ LX YB FP QD US IH CE GR"
+                ]
+            }
+        ]
+    },
+    {
+        // Decryption test on above input
+        name: "Enigma: decryption",
+        input: "GHLIM OJIUW DKLWM JGNJK DYJVD K",
+        expectedOutput: "AAAAA AAAAA AAAAA AAAAA AAAAA A",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "4-rotor",
+                    "FSOKANUERHMBTIYCWLQPZXVGJD", "A", "I", // Gamma
+                    "NZJHGRCXMYSWBOUFAIVLPEKQDT<AN", "I", "V", // VII
+                    "ESOVPZJAYQUIRHXLNFTGKDCMWB<K", "O", "O", // IV
+                    "FKQHTLXOCBJSPDZRAMEWNIUYGV<AN", "U", "Z", // VIII
+                    "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV", // B thin
+                    "WN MJ LX YB FP QD US IH CE GR"
+                ]
+            }
+        ]
+    },
+    {
+        // Decryption test on real message
+        name: "Enigma: decryption 2",
+        input: "LANOTCTOUARBBFPMHPHGCZXTDYGAHGUFXGEWKBLKGJWLQXXTGPJJAVTOCKZFSLPPQIHZFXOEBWIIEKFZLCLOAQJULJOYHSSMBBGWHZANVOIIPYRBRTDJQDJJOQKCXWDNBBTYVXLYTAPGVEATXSONPNYNQFUDBBHHVWEPYEYDOHNLXKZDNWRHDUWUJUMWWVIIWZXIVIUQDRHYMNCYEFUAPNHOTKHKGDNPSAKNUAGHJZSMJBMHVTREQEDGXHLZWIFUSKDQVELNMIMITHBHDBWVHDFYHJOQIHORTDJDBWXEMEAYXGYQXOHFDMYUXXNOJAZRSGHPLWMLRECWWUTLRTTVLBHYOORGLGOWUXNXHMHYFAACQEKTHSJW",
+        expectedOutput: "KRKRALLEXXFOLGENDESISTSOFORTBEKANNTZUGEBENXXICHHABEFOLGELNBEBEFEHLERHALTENXXJANSTERLEDESBISHERIGXNREICHSMARSCHALLSJGOERINGJSETZTDERFUEHRERSIEYHVRRGRZSSADMIRALYALSSEINENNACHFOLGEREINXSCHRIFTLSCHEVOLLMACHTUNTERWEGSXABSOFORTSOLLENSIESAEMTLICHEMASSNAHMENVERFUEGENYDIESICHAUSDERGEGENWAERTIGENLAGEERGEBENXGEZXREICHSLEITEIKKTULPEKKJBORMANNJXXOBXDXMMMDURNHFKSTXKOMXADMXUUUBOOIEXKP",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "4-rotor",
+                    "LEYJVCNIXWPBQMDRTAKZGFUHOS", "E", "C", // Beta
+                    "VZBRGITYUPSDNHLXAWMJQOFECK<A", "P", "D", // V
+                    "JPGVOUMFYQBENHZRDKASXLICTW<AN", "E", "S", // VI
+                    "FKQHTLXOCBJSPDZRAMEWNIUYGV<AN", "L", "Z", // VIII
+                    "AR BD CO EJ FN GT HK IV LM PW QZ SX UY", // C thin
+                    "AE BF CM DQ HU JN LX PR SZ VW"
+                ]
+            }
+        ]
+    },
+    {
+        // Non-alphabet characters drop test
+        name: "Enigma: non-alphabet drop",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "ILBDA AMTAZ MORNZ DDIOT U",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "", true
+                ]
+            }
+        ]
+    },
+    {
+        // Non-alphabet characters passthrough test
+        name: "Enigma: non-alphabet passthrough",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "ILBDA, AMTAZ. MORN ZD D IOTU.",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "", false
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: rotor validation 1",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Rotor wiring must be 26 unique uppercase letters",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQ", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: rotor validation 2",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Rotor wiring must be 26 unique uppercase letters",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQo", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: rotor validation 3",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Rotor wiring must have each letter exactly once",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQA", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: rotor validation 4",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Rotor steps must be unique",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<RR", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: rotor validation 5",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Rotor steps must be 0-26 unique uppercase letters",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<a", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    // The ring setting and positions are dropdowns in the interface so not
+    // gonna bother testing them
+    {
+        name: "Enigma: reflector validation 1",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Reflector must have exactly 13 pairs covering every letter",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "A", // III
+                    "AY BR CU DH EQ FS GL IP JX KN MO", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: reflector validation 2",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Reflector must have exactly 13 pairs covering every letter",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "A", // III
+                    "AA BR CU DH EQ FS GL IP JX KN MO TZ VV WY", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: reflector validation 3",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Reflector connects A more than once",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "A", // III
+                    "AY AR CU DH EQ FS GL IP JX KN MO TZ", // B
+                    ""
+                ]
+            }
+        ]
+    },
+    {
+        name: "Enigma: reflector validation 4",
+        input: "Hello, world. This is a test.",
+        expectedOutput: "Reflector must be a whitespace-separated list of uppercase letter pairs",
+        recipeConfig: [
+            {
+                "op": "Enigma",
+                "args": [
+                    "3-rotor",
+                    "", "A", "A",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R", "A", "A", // I
+                    "AJDKSIRUXBLHWTMCQGZNPYFVOE<F", "A", "A", // II
+                    "BDFHJLCPRTXVZNYEIWGAKMUSQO<W", "A", "A", // III
+                    "AYBR CU DH EQ FS GL IP JX KN MO TZ", // B
+                    ""
+                ]
+            }
+        ]
+    },
+]);

tests/operations/tests/MultipleBombe.mjs

@@ -0,0 +1,49 @@
+/**
+ * Bombe machine tests.
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import TestRegister from "../TestRegister";
+
+TestRegister.addTests([
+    {
+        name: "Multi-Bombe: 3 rotor",
+        input: "BBYFLTHHYIJQAYBBYS",
+        expectedMatch: /<td>LGA<\/td> {2}<td>SS<\/td> {2}<td>VFISUSGTKSTMPSUNAK<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Multiple Bombe",
+                "args": [
+                    // I, II and III
+                    "User defined",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R\nAJDKSIRUXBLHWTMCQGZNPYFVOE<F\nBDFHJLCPRTXVZNYEIWGAKMUSQO<W",
+                    "",
+                    "AY BR CU DH EQ FS GL IP JX KN MO TZ VW", // B
+                    "THISISATESTMESSAGE", 0, false
+                ]
+            }
+        ]
+    },
+    /*
+     * This is too slow to run regularly
+    {
+        name: "Multi-Bombe: 4 rotor",
+        input: "LUOXGJSHGEDSRDOQQX",
+        expectedMatch: /<td>LHSC<\/td><td>SS<\/td><td>HHHSSSGQUUQPKSEKWK<\/td>/,
+        recipeConfig: [
+            {
+                "op": "Multiple Bombe",
+                "args": [
+                    // I, II and III
+                    "User defined",
+                    "EKMFLGDQVZNTOWYHXUSPAIBRCJ<R\nAJDKSIRUXBLHWTMCQGZNPYFVOE<F\nBDFHJLCPRTXVZNYEIWGAKMUSQO<W",
+                    "LEYJVCNIXWPBQMDRTAKZGFUHOS", // Beta
+                    "AE BN CK DQ FU GY HW IJ LO MP RX SZ TV", // B thin
+                    "THISISATESTMESSAGE", 0, false
+                ]
+            }
+        ]
+    },
+    */
+]);

tests/operations/tests/Typex.mjs

@@ -0,0 +1,105 @@
+/**
+ * Typex machine tests.
+ * @author s2224834
+ * @copyright Crown Copyright 2019
+ * @license Apache-2.0
+ */
+import TestRegister from "../TestRegister";
+
+TestRegister.addTests([
+    {
+        // Unlike Enigma we're not verifying against a real machine here, so this is just a test
+        // to catch inadvertent breakage.
+        name: "Typex: basic",
+        input: "hello world, this is a test message.",
+        expectedOutput: "VIXQQ VHLPN UCVLA QDZNZ EAYAT HWC",
+        recipeConfig: [
+            {
+                "op": "Typex",
+                "args": [
+                    "MCYLPQUVRXGSAOWNBJEZDTFKHI<BFHNQUW",
+                    false, "B", "C",
+                    "KHWENRCBISXJQGOFMAPVYZDLTU<BFHNQUW",
+                    false, "D", "E",
+                    "BYPDZMGIKQCUSATREHOJNLFWXV<BFHNQUW",
+                    false, "F", "G",
+                    "ZANJCGDLVHIXOBRPMSWQUKFYET<BFHNQUW",
+                    true, "H", "I",
+                    "QXBGUTOVFCZPJIHSWERYNDAMLK<BFHNQUW",
+                    true, "J", "K",
+                    "AN BC FG IE KD LU MH OR TS VZ WQ XJ YP",
+                    "EHZTLCVKFRPQSYANBUIWOJXGMD",
+                    "None", true
+                ]
+            }
+        ]
+    },
+    {
+        name: "Typex: keyboard",
+        input: "hello world, this is a test message.",
+        expectedOutput: "VIXQQ FDJXT WKLDQ DFQOD CNCSK NULBG JKQDD MVGQ",
+        recipeConfig: [
+            {
+                "op": "Typex",
+                "args": [
+                    "MCYLPQUVRXGSAOWNBJEZDTFKHI<BFHNQUW",
+                    false, "B", "C",
+                    "KHWENRCBISXJQGOFMAPVYZDLTU<BFHNQUW",
+                    false, "D", "E",
+                    "BYPDZMGIKQCUSATREHOJNLFWXV<BFHNQUW",
+                    false, "F", "G",
+                    "ZANJCGDLVHIXOBRPMSWQUKFYET<BFHNQUW",
+                    true, "H", "I",
+                    "QXBGUTOVFCZPJIHSWERYNDAMLK<BFHNQUW",
+                    true, "J", "K",
+                    "AN BC FG IE KD LU MH OR TS VZ WQ XJ YP",
+                    "EHZTLCVKFRPQSYANBUIWOJXGMD",
+                    "Encrypt", true
+                ]
+            }
+        ]
+    },
+    {
+        name: "Typex: self-decrypt",
+        input: "hello world, this is a test message.",
+        expectedOutput: "HELLO WORLD, THIS IS A TEST MESSAGE.",
+        recipeConfig: [
+            {
+                "op": "Typex",
+                "args": [
+                    "MCYLPQUVRXGSAOWNBJEZDTFKHI<BFHNQUW",
+                    false, "B", "C",
+                    "KHWENRCBISXJQGOFMAPVYZDLTU<BFHNQUW",
+                    false, "D", "E",
+                    "BYPDZMGIKQCUSATREHOJNLFWXV<BFHNQUW",
+                    false, "F", "G",
+                    "ZANJCGDLVHIXOBRPMSWQUKFYET<BFHNQUW",
+                    true, "H", "I",
+                    "QXBGUTOVFCZPJIHSWERYNDAMLK<BFHNQUW",
+                    true, "J", "K",
+                    "AN BC FG IE KD LU MH OR TS VZ WQ XJ YP",
+                    "EHZTLCVKFRPQSYANBUIWOJXGMD",
+                    "Encrypt", true
+                ]
+            },
+            {
+                "op": "Typex",
+                "args": [
+                    "MCYLPQUVRXGSAOWNBJEZDTFKHI<BFHNQUW",
+                    false, "B", "C",
+                    "KHWENRCBISXJQGOFMAPVYZDLTU<BFHNQUW",
+                    false, "D", "E",
+                    "BYPDZMGIKQCUSATREHOJNLFWXV<BFHNQUW",
+                    false, "F", "G",
+                    "ZANJCGDLVHIXOBRPMSWQUKFYET<BFHNQUW",
+                    true, "H", "I",
+                    "QXBGUTOVFCZPJIHSWERYNDAMLK<BFHNQUW",
+                    true, "J", "K",
+                    "AN BC FG IE KD LU MH OR TS VZ WQ XJ YP",
+                    "EHZTLCVKFRPQSYANBUIWOJXGMD",
+                    "Decrypt", true
+                ]
+            }
+        ]
+    },
+]);

webpack.config.js

@@ -100,8 +100,15 @@ module.exports = {
                     limit: 10000
                 }
             },
+            {
+                test: /\.svg$/,
+                loader: "svg-url-loader",
+                options: {
+                    encoding: "base64"
+                }
+            },
             { // First party images are saved as files to be cached
-                test: /\.(png|jpg|gif|svg)$/,
+                test: /\.(png|jpg|gif)$/,
                 exclude: /node_modules/,
                 loader: "file-loader",
                 options: {
@@ -109,7 +116,7 @@ module.exports = {
                 }
             },
             { // Third party images are inlined
-                test: /\.(png|jpg|gif|svg)$/,
+                test: /\.(png|jpg|gif)$/,
                 exclude: /web\/static/,
                 loader: "url-loader",
                 options: {