signalmail

signalmail is a Python script to forward Signal messages via email. It relies on signal-cli (https://github.com/AsamK/signal-cli) running in daemon mode to fetch the actual messages. Configuration is done in by copying config_default.ini to $HOME/.local/share/signalmail/config.ini and modifying it.

Please note that messages are NOT END-TO-END ENCRYPTED. Signalmail is an UNOFFICIAL program that does not connect directly to the Signal servers. Messages and attachments are sent "in the clear" via DBus on the local computer, so signalmail relies on DBus security to protect your message. Further, signal-cli is an UNOFFICIAL client that does connect directly to the Signal servers. It is signal-cli that encrypts and decrypts the messages.

Finally, forwarding the message via email is inherently insecure, using the SMTP protocol.

CLI arguments

You may pass the following arguments to signalbot.py:

• --no-sendmail override config and do not send mail
• --debug override config and switch on debug mode
• --keepattachments override config and keep attachments after processing
• --autoreply text of a reply to each incoming Signal message
• --autoattach path to file to send as attachment with autoreply
• --system override config and use system DBus

Known issues

• users are untrusted if they reinstall Signal and therefore messages don't come through. See https://github.com/AsamK/signal-cli/wiki/Manage-trusted-keys

  As a workaround using signal-cli:

  • If you don't care about security, you can manually trust the new key
    signal-cli -u yourNumber trust -a untrustedNumber
  • Better is to verify it with the remote number's SAFETY_NUMBER
    signal-cli -u yourNumber trust -v SAFETY_NUMBER -a untrustedNumber

ToDos

• add possibility to choose between multiple groups to be forwarded to different recipients