SSH, The Secure Shell: The Definitive Guide, 2nd Edition

Pine, IMAP, and SSH

Pine is a popular, Unix-based email program from the University of Washington (http://www.washington.edu/pine/). In addition to handling mail stored and delivered in local files, Pine also supports IMAP^[146] for accessing remote mailboxes and SMTP^[147] for posting mail.

In this case study, we integrate Pine and SSH to solve two common problems:

IMAP authentication

In many cases, IMAP permits a password to be sent in the clear over the network. We discuss how to protect your password using SSH, but (surprisingly) not by port forwarding.

Restricted mail relaying

Many ISPs permit their mail and news servers to be accessed only by their customers. In some circumstances, this restriction may prevent you from legitimately relaying mail through your ISP. Once again, SSH comes to the rescue.

We also discuss techniques to avoid Pine connection delays and facilitate access to multiple servers and mailboxes, including the use of a Pine-specific SSH connection script. This discussion will delve into more detail than the previous one on Pine/SSH integration. [4.5.3]

11.3.1 Securing IMAP Authentication

Like SSH, IMAP is a client/server protocol. Your email program (e.g., Pine) is the client, and an IMAP server process (e.g., imapd ) runs on a remote machine, the IMAP host, to control access to your remote mailbox. Also like SSH, IMAP generally requires you to authenticate before accessing your mailbox, typically by password. Unfortunately, in some cases this password is sent to the ...