pgpmime-decrypt is a Python 3 script for decrypting PGP/MIME messages on
the command line. It requires a working GnuPG 2 installation and, of course,
the correct secret key.

WARNING: THIS SCRIPT HAS NOT BEEN TESTED THOROUGHLY AND IS
NOT RECOMMENDED FOR PRODUCTION USE. ALWAYS KEEP BACKUPS OF YOUR MESSAGES!

Dependencies:

- GnuPG 2 <https://www.gnupg.org/>
- Python 3.4 <https://www.python.org/>
- PyGPGME 0.3 <https://launchpad.net/products/pygpgme>

On Debian (Jessie), you can install all dependencies with this command:

$ apt-get install python3-gpgme

Usage as a filter:

$ pgpmime-decrypt < input > output

Usage for operating on a message file in place:

$ pgpmime-decrypt -f filename

Note that pgpmime-decrypt only processes a single message at time; it does
not handle mbox files. If you feed it an mbox, it might even read the first
message from it and discard the rest (I have not tested this), so be careful.

To keep the original message as a message/rfc822 attachment, you can add
the --keep option. This is strongly recommended, though some mail clients
may not be able to display these attachments correctly, and the message
contents will probably be displayed twice (once for the decrypted part,
and once again for the attachment).

To use this script as an action in Claws Mail, so you can permanently
decrypt messages from the GUI, choose Configuration - Actions and enter
the following shell command:

/path/to/pgpmime-decrypt -f "%f"

GitHub: https://github.com/kianga/pgpmime
Send feedback to: René Puls <rpuls@kcore.de> (PGP key: D8C3477F8B64D678)