GPGMAILTUNL(1)

NAME
gpgmailtunl - Encrypts an email message into the body of another email.

SYNOPSIS
gpgmailtunl [options] --encrypt | --decrypt

DESCRIPTION
gpgmailtunl is a filter program that either encrypts an email message using the Gnu Privacy Guard and sends it to another recipient or decrypt an email message and forwards unencrypted to another destination.

It can be used to exchange emails across an open network betweeen two trusted systems.

TYPICAL USAGE
This program is intended to run from program like procmail or sendmail to create an email tunnel between two systems. Of course this is not as secure as using gpg as an end user program, it may be convenient in certain case.

ENCRYPTION
To encapsulates an email within another you pipe the message to gpgmailtunl.

  OPTIONS
GetOptions( \%opt, "encrypt", "decrypt", "sign", "secret-file=s",
        "from=s", "to=s", "subject=s", "homedir=s", "local-user=s",
        "recipient=s",
      )
  or usage;

to  This is the address to which the encrypted message will be sent. This is the only required fields.

recipient
    This sets the keyid that will be used to encrypt the outgoing message. If unset, gpgmailtunl will try to find a key matching the to option.

subject
    Sets the subject of the outgoing message. This defaults to "Encrypted mail".

from
    Sets the From header line of the outgoing message which will contains the encrypted one. sendmail will provides a default one if this is not set.

sign
    If this option is used, the outgoing message will be signed. In this case you should probably use to local-user and secret-file options.

secret-file
    File from which the secret to unlock the private used to sign the message can be read.

local-user
    The keyid of the user that should sign the outgoing message. The default user will be used if not specified.

homedir
    Sets an alternate gpg home directory. (This is where the keyrings are stored.)

DECRYPTION
To extract an email to be forwarded to the final user you pipe the encrypted email to gpgmailtunl using the decrypt switch.

Once decrypted, the encapsulated email message will be sent to the original destinator of the message.

  OPTIONS

homedir
    Sets an alternate gpg home directory. (This is where the keyrings are stored.)

secret-file
    File from which the secret to unlock the private used to decrypt the message can be read.

AUTHOR
Francis J. Lacoste <francis.lacoste@iNsu.COM>

COPYRIGHT
Copyright (c) 1999, 2000 iNsu Innovations Inc.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

SEE ALSO
gpg(1) gpgmailtunl(1) GnuPG(3)