ente/migration-guides/decrypt/decrypt.go
2023-09-05 13:14:30 +05:30

105 lines
2.2 KiB
Go

package main
import (
"encoding/base64"
"encoding/json"
"fmt"
"os"
)
type Export struct {
Version int `json:"version"`
KDFParams KDF `json:"kdfParams"`
EncryptedData string `json:"encryptedData"`
EncryptionNonce string `json:"encryptionNonce"`
}
type KDF struct {
MemLimit int `json:"memLimit"`
OpsLimit int `json:"opsLimit"`
Salt string `json:"salt"`
}
func resolvePath(path string) (string, error) {
if path[:2] != "~/" {
return path, nil
}
home, err := os.UserHomeDir()
if err != nil {
return "", err
}
return home + path[1:], nil
}
func main() {
defer func() {
if err := recover(); err != nil {
fmt.Println("Error:", err)
}
}()
if len(os.Args) != 4 {
fmt.Println("Usage: ./decrypt <export_file> <password> <output_file>")
return
}
exportFile, err := resolvePath(os.Args[1])
if err != nil {
fmt.Println("Error resolving exportFile path:", err)
return
}
password := os.Args[2]
outputFile, err := resolvePath(os.Args[3])
if err != nil {
fmt.Println("Error resolving outputFile path:", err)
return
}
data, err := os.ReadFile(exportFile)
if err != nil {
fmt.Println("Error reading file:", err)
return
}
var export Export
if err := json.Unmarshal(data, &export); err != nil {
fmt.Println("Error parsing JSON:", err)
return
}
if export.Version != 1 {
fmt.Println("Unsupported version")
return
}
encryptedData, err := base64.StdEncoding.DecodeString(export.EncryptedData)
if err != nil {
fmt.Println("Error decoding encrypted data:", err)
return
}
nonce, err := base64.StdEncoding.DecodeString(export.EncryptionNonce)
if err != nil {
fmt.Println("Error decoding nonce:", err)
return
}
key, err := deriveArgonKey(password, export.KDFParams.Salt, export.KDFParams.MemLimit, export.KDFParams.OpsLimit)
if err != nil {
fmt.Println("Error deriving key:", err)
return
}
decryptedData, err := decryptChaCha20poly1305(encryptedData, key, nonce)
if err != nil {
fmt.Println("Error decrypting data:", err)
return
}
if err := os.WriteFile(outputFile, decryptedData, 0644); err != nil {
fmt.Println("Error writing decrypted data to file:", err)
return
}
fmt.Printf("Decrypted data written to %s\n", outputFile)
}