Re: [OT]sendmail ssl authentication

[David <de_bb@arcor.de>]

reader@newsguy.com writes:
> And it does appear there may be some hope since I see mention of
> STARTTLS in the output of swaks:
>   
> reader > swaks --auth --tls-on-connect -p 465 -s smtp.comcast.net   
> To: reader@jtan.com
> Username: My-uid
> Password: My-passwd
> === Trying smtp.comcast.net:465...
> === Connected to smtp.comcast.net.
> === TLS started w/ cipher DHE-RSA-AES256-SHA
> <~  220 OMTA02.emeryville.ca.mail.comcast.net comcast ESMTP server ready

The "--tls-on-connect" initiates a ssmtp connection, i.e. the TLS
session is started right away so that everything is already encrypted
(even the server greeting).

When I telnet to smtp.comcast.net on the SMTP standard port (25) I also
see a "250-STARTTLS" after the EHLO handshake, so this server should
support STARTTLS on the standard port, and that's the correct thing to
do for SSL encrypted authentication. You can try it with

swaks --auth -tls -p 25 -s smtp.comcast.net

If this works, configure sendmail to do authentication with STARTTLS on
the standard port 25 and don't use port 465. If it doesn't work, you
might indeed have to set up stunnel if sendmail doesn't support ssmtp
directly.

-David