Merge pull request #21861 from jfrazelle/apparmor-examples-for-the-apparmor-gods

Add example to apparmor docs

docs/security/apparmor.md

@@ -20,8 +20,8 @@ Docker automatically loads container profiles. The Docker binary installs
 a `docker-default` profile in the `/etc/apparmor.d/docker` file. This profile
 is used on containers, _not_ on the Docker Daemon.
 
-A profile for the Docker Engine Daemon exists but it is not currently installed 
-with the deb packages. If you are interested in the source for the Daemon
+A profile for the Docker Engine daemon exists but it is not currently installed
+with the `deb` packages. If you are interested in the source for the daemon
 profile, it is located in
 [contrib/apparmor](https://github.com/docker/docker/tree/master/contrib/apparmor)
 in the Docker Engine source repository.
@@ -72,15 +72,15 @@ explicitly specifies the default policy:
 $ docker run --rm -it --security-opt apparmor=docker-default hello-world
 ```
 
-## Loading and Unloading Profiles
+## Load and unload profiles
 
-To load a new profile into AppArmor, for use with containers:
+To load a new profile into AppArmor for use with containers:
 
-```
+```bash
 $ apparmor_parser -r -W /path/to/your_profile
 ```
 
-Then you can run the custom profile with `--security-opt` like so:
+Then, run the custom profile with `--security-opt` like so:
 
 ```bash
 $ docker run --rm -it --security-opt apparmor=your_profile hello-world
@@ -97,39 +97,174 @@ $ apparmor_parser -R /path/to/profile
 $ /etc/init.d/apparmor start
 ```
 
-## Debugging AppArmor
+### Resources for writing profiles
+
+The syntax for file globbing in AppArmor is a bit different than some other
+globbing implementations. It is highly suggested you take a look at some of the
+below resources with regard to AppArmor profile syntax.
+
+- [Quick Profile Language](http://wiki.apparmor.net/index.php/QuickProfileLanguage)
+- [Globbing Syntax](http://wiki.apparmor.net/index.php/AppArmor_Core_Policy_Reference#AppArmor_globbing_syntax)
+
+## Nginx example profile
+
+In this example, you create a custom AppArmor profile for Nginx. Below is the
+custom profile.
+
+```
+#include <tunables/global>
+
+
+profile docker-nginx flags=(attach_disconnected,mediate_deleted) {
+  #include <abstractions/base>
+
+  network inet tcp,
+  network inet udp,
+  network inet icmp,
+
+  deny network raw,
+
+  deny network packet,
+
+  file,
+  umount,
+
+  deny /bin/** wl,
+  deny /boot/** wl,
+  deny /dev/** wl,
+  deny /etc/** wl,
+  deny /home/** wl,
+  deny /lib/** wl,
+  deny /lib64/** wl,
+  deny /media/** wl,
+  deny /mnt/** wl,
+  deny /opt/** wl,
+  deny /proc/** wl,
+  deny /root/** wl,
+  deny /sbin/** wl,
+  deny /srv/** wl,
+  deny /tmp/** wl,
+  deny /sys/** wl,
+  deny /usr/** wl,
+
+  audit /** w,
+
+  /var/run/nginx.pid w,
+
+  /usr/sbin/nginx ix,
+
+  deny /bin/dash mrwklx,
+  deny /bin/sh mrwklx,
+  deny /usr/bin/top mrwklx,
+
+
+  capability chown,
+  capability dac_override,
+  capability setuid,
+  capability setgid,
+  capability net_bind_service,
+
+  deny @{PROC}/{*,**^[0-9*],sys/kernel/shm*} wkx,
+  deny @{PROC}/sysrq-trigger rwklx,
+  deny @{PROC}/mem rwklx,
+  deny @{PROC}/kmem rwklx,
+  deny @{PROC}/kcore rwklx,
+  deny mount,
+  deny /sys/[^f]*/** wklx,
+  deny /sys/f[^s]*/** wklx,
+  deny /sys/fs/[^c]*/** wklx,
+  deny /sys/fs/c[^g]*/** wklx,
+  deny /sys/fs/cg[^r]*/** wklx,
+  deny /sys/firmware/efi/efivars/** rwklx,
+  deny /sys/kernel/security/** rwklx,
+}
+```
+
+1. Save the custom profile to disk in the
+`/etc/apparmor.d/containers/docker-nginx` file.
+
+    The file path in this example is not a requirement. In production, you could
+    use another.
+
+2. Load the profile.
+
+    ```bash
+    $ sudo apparmor_parser -r -W /etc/apparmor.d/containers/docker-nginx
+    ```
+
+3. Run a container with the profile.
+
+    To run nginx in detached mode:
+
+    ```bash
+    $ docker run --security-opt "apparmor=docker-nginx" \
+        -p 80:80 -d --name apparmor-nginx nginx
+    ```
+
+4. Exec into the running container
+
+    ```bash
+    $ docker exec -it apparmor-nginx bash
+    ```
+
+5. Try some operations to test the profile.
+
+    ```bash
+    root@6da5a2a930b9:~# ping 8.8.8.8
+    ping: Lacking privilege for raw socket.
+
+    root@6da5a2a930b9:/# top
+    bash: /usr/bin/top: Permission denied
+
+    root@6da5a2a930b9:~# touch ~/thing
+    touch: cannot touch 'thing': Permission denied
+
+    root@6da5a2a930b9:/# sh
+    bash: /bin/sh: Permission denied
+
+    root@6da5a2a930b9:/# dash
+    bash: /bin/dash: Permission denied
+    ```
+
+
+Congrats! You just deployed a container secured with a custom apparmor profile!
+
+
+## Debug AppArmor
+
+You can use `demsg` to debug problems and `aa-status` check the loaded profiles.
 
-### Using `dmesg`
+### Use dmesg
 
 Here are some helpful tips for debugging any problems you might be facing with
 regard to AppArmor.
 
 AppArmor sends quite verbose messaging to `dmesg`. Usually an AppArmor line
-will look like the following:
+looks like the following:
 
 ```
 [ 5442.864673] audit: type=1400 audit(1453830992.845:37): apparmor="ALLOWED" operation="open" profile="/usr/bin/docker" name="/home/jessie/docker/man/man1/docker-attach.1" pid=10923 comm="docker" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0
 ```
 
-In the above example, the you can see `profile=/usr/bin/docker`. This means the
+In the above example, you can see `profile=/usr/bin/docker`. This means the
 user has the `docker-engine` (Docker Engine Daemon) profile loaded.
 
 > **Note:** On version of Ubuntu > 14.04 this is all fine and well, but Trusty
 > users might run into some issues when trying to `docker exec`.
 
-Let's look at another log line:
+Look at another log line:
 
 ```
 [ 3256.689120] type=1400 audit(1405454041.341:73): apparmor="DENIED" operation="ptrace" profile="docker-default" pid=17651 comm="docker" requested_mask="receive" denied_mask="receive"
 ```
 
 This time the profile is `docker-default`, which is run on containers by
-default unless in `privileged` mode. It is telling us, that apparmor has denied
-`ptrace` in the container. This is great.
+default unless in `privileged` mode. This line shows that apparmor has denied
+`ptrace` in the container. This is exactly as expected.
 
-### Using `aa-status`
+### Use aa-status
 
-If you need to check which profiles are loaded you can use `aa-status`. The
+If you need to check which profiles are loaded,  you can use `aa-status`. The
 output looks like:
 
 ```bash
@@ -162,17 +297,17 @@ apparmor module is loaded.
 0 processes are unconfined but have a profile defined.
 ```
 
-In the above output you can tell that the `docker-default` profile running on
-various container PIDs is in `enforce` mode. This means AppArmor will actively
-block and audit in `dmesg` anything outside the bounds of the `docker-default`
+The above output shows that the `docker-default` profile running on various
+container PIDs is in `enforce` mode. This means AppArmor is actively blocking
+and auditing in `dmesg` anything outside the bounds of the `docker-default`
 profile.
 
-The output above also shows the `/usr/bin/docker` (Docker Engine Daemon)
-profile is running in `complain` mode. This means AppArmor will _only_ log to
-`dmesg` activity outside the bounds of the profile. (Except in the case of
-Ubuntu Trusty, where we have seen some interesting behaviors being enforced.)
+The output above also shows the `/usr/bin/docker` (Docker Engine daemon) profile
+is running in `complain` mode. This means AppArmor _only_ logs to `dmesg`
+activity outside the bounds of the profile. (Except in the case of Ubuntu
+Trusty, where some interesting behaviors are enforced.)
 
-## Contributing to AppArmor code in Docker
+## Contribute Docker's AppArmor code
 
 Advanced users and package managers can find a profile for `/usr/bin/docker`
 (Docker Engine Daemon) underneath