The program can take a target encrypted directory on the command line.If unspecified, the utility will search the entire system looking for encrypted private directories, as configured by ecryptfs-setup-private.
If an encrypted directory and a wrapped-passphrase file are found, the user is prompted for the login (wrapping) passphrase, the keys are inserted into the keyring, and the data is decrypted and mounted.
If no wrapped-passphrase file is found, the user will be prompted for their mount passphrase. This passphrase is typically 32 characters of [0-9a-f]. All users are prompted to urgently record this randomly generated passphrase when they first setup their encrypted private directory.
The destination mount of the decrypted data is a temporary directory,in the form of /tmp/ecryptfs.XXXXXXXX.
Procedure to follow
If you find yourself in a situation where you need to recover your Encrypted Home or Encrypted Private directory, simply:
1)boot the target system using an Ubuntu 11.04 Desktop LiveCD
2)make sure that your target system's hard drive is mounted
3)open a terminal and run ‘sudo ecryptfs-recover-private'follow the prompts
access your decrypted data and save somewhere else
The utility will do a deep find of the system's hard disk, looking for folders named ".Private", and will interactively ask you if it's the folder you'd like to recover. If you answer "yes", you will then be prompted for the login passphrase that's used to decrypt your wrapped, mount passphrase. Assuming you have the correct credentials, it will mount your Encrypted Home or Private directory in read-only mode, and point you at the temporary directory where it's mounted.
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