schof wrote:
As I understand it, I need to enable some kind of wrapper (either sasl or sslwrap or something else) that will accept incoming SSL connection on behalf of the daemon listening at that port, and then pass the decrypted communication to the correct daemon.
That is one way, but postfix can do this naturally via a TLS patch. Check out the docs on postfix.org and my own (WIP) howto at:
http://opencurve.org/~sunny/nix/postfix/. Its far from being done, but it covers SASL, and TLS/SSL
As for IMAP-SSL? Courier-IMAP does that super easy. Their documentation is all one needs. However you may find yourself doing the following so that you don't use Courier-IMAP's broken PAM setup.
cp /etc/pam.d/other /etc/pam.d/pop3
cp /etc/pam.d/other /etc/pam.d/imap
schof wrote:
How would I then configure my mail client? Obviously to use SSL in the connection, but what about authentication? Password or Kerberos 4 or 5 or MD5 Challenge-Response?
Careful here,
not all SASL authentication mechanisms work with all authentication sources. IIRC Pam only works with PLAIN and LOGIN. However saslauthdb works with CRAM-MD5, DIGEST-MD5. You gotta figure all of this out at compile time. (When you think about one way encryption hashes, you'll see why this is true.)
To make things more confusing PLAIN and LOGIN cannot be sent over a clear text network. However CRAM and DIGEST can.
Sunny Dubey
PS: Sorry for screwing up the posting