eDiscovery tool for bulk decryption of emails in a batch of PST files or loose .eml files, written in Go.

This project is a successor to batch-decipher-pst.

This is a containerized command line tool. However, using a container is only necessary if processing PST archives. I work on a Fedora system using Podman but Docker will work fine as well.

This depends on readpst from the libpst tools for unpacking PST archives. You don't need readpst if you aren't using PST files as input. The version used is compiled from the git repo source, as there are bug fixes that haven't made it into a release yet.

See below for how to build readpst.

I wanted to use go-pst but there is an issue with .msg emails that are attached to other emails. Also, go-pst is not thread-safe. go-pst is used for the getheaders command, and readpst is not required for that command.

If you don't need PST support, simply build the normal way for a Go project. Note: you can easily cross-compile in Go by setting the GOOS environment variable.

go build

First, build readpst.

cd readpst
buildah bud -t readpst .

Next, build the production container.

cd ..
buildah bud -t enigma .

This is not a cracking tool. You will need a legitimate way of obtaining certs and keys from escrow. Two helper commands are provided to help you identify encrypted emails and custodian cert info.

getsigs : Search the sent items folder for signed emails and get certificate metadata showing dates, certificate authority, etc.

getheaders : Collect metadata from email headers and identify if the email is encrypted. NOTE: This doesn't recurse into .msg attachments it looks 1 level deep.

If you have sufficient RAM available, mount a tmpfs to the path /mnt/ramdisk/unpack. This path is used by readpst as a temp workspace for unpacking PST files into text format for further processing. NOTE: This is only available on a Linux host.

Change into your directory with your input files and mount to the path /cases.

podman run -it --rm --tmpfs /mnt/ramdisk/unpack:U -v $(pwd):/cases:Z --userns=keep-id enigma:latest /bin/bash

Enigma uses the Cobra Command framework and has help switches --help. It also uses a YAML config file loaded by Viper. An example config with explanations is provided as config.example.yaml.

Simply run enigma without any sub-commands to get a help overview of how to use the tool. Help is available for every command, ex. enigma decipher --help.