---
name: "gpgmailtunl"
section: "1p"
platform: "linux"
package: "libgnupg-perl"
version: "0.19-5"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/gpgmailtunl"
---

# gpgmailtunl(1p)

Encrypts an email message into the body of another email.

## 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 between 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)](/gpg/1.md) **gpgmailtunl**(1) **GnuPG**(3)