Decrypt Synology Backups in Linux

Scenario

You have access to a folder encrypted by a Synology NAS in Linux and you want to decrypt it (without the Synology). Example: offsite backup of an encrypted Synology folder.

Steps

1. Install ecryptfs

   $ sudo apt-get install ecryptfs-utils
   

2. Create a mount point

   sudo mkdir /mnt/synology
   

3. Mount the folder Mount the folder and use the password/key from the original encryption on the Synology.

   $ mount -t ecryptfs /path/to/src /mnt/synology_decrypt
   # aes
   # 32 bytes
   # plaintext passthrough - n
   # filename encryption - y
   

   NOTE: the src folder must not be nested inside a folder encrypted using ecryptfs (ex: encrypted Ubuntu home folder)

References

• http://robertcastle.com/2012/10/howto-recover-synology-encrypted-folders-in-linux/
• http://www.thenakedscientists.com/forum/index.php?topic=49888.0