The basic issue delt with the inability of our mailer (sendmail 8.8.6,
running on a solaris platform) to handle incoming mail with an address of
the form:
mailto:username@nps.navy.mil
where username is a valid user it's being sent to! We wanted to "trap"
enough information to identify the actual sender, and notify him/her of
the problem.
I got a number of very helpful responses - thanks to all - which
fell into the following general categories:
(1) Turn on logging (syslog) at a high enough level to capture
the complete transaction data, which would identify the
distant sender and host, e.g.
| Apr 20 20:58:42 penthesilea sendmail[18976]: UAA18976:
| <foo@bar.uni-trier.de>... AntiSpam Setup - No free Relaying
| Apr 20 20:58:42 penthesilea sendmail[18976]:
| Ruleset check_rcpt (<foo@bar.uni-trier.de>) rejection:
| 571 <foo@bar.uni-trier.de>... AntiSpam Setup - No free Relaying
| Apr 20 20:58:42 penthesilea sendmail[18976]: UAA18976:
| from=<bern@penthesilea.uni-trier.de>, size=769, class=0, pri=0,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
| nrcpts=0, proto=ESMTP, relay=baz.uni-trier.de [136.199.4711]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This was the easiest "fix," and what we did. In about 20 minutes
we got the "trap" we needed. (Because our host is a campus
mailhub for over 3,000 users, we didn't have that level of logging
turned on.)
(2) Rewrite some of the rules in sendmail.cf to delete the
mailto:
portion of the address, e.g. near the top of S3 include one
of the following rewrites:
R$*mailto:$* $1$2 Drop mailto entirely
We'll likely experiment with this, at some time in the future,
but haven't tried it yet.
(4) Use filters or wrappers. Didn't use because it looked to be
too much work, and we didn't wan't to reject these messages,
but wanted, unless this was legitimate "spam," contact the
sender and help them be able to deliver to the intended
recipients.
(4) Try the sendmail list(s), e.g.:
sendmail-questions@sendmail.org
(Didn't need to, since we got more than enough help here!)
Thanks to (in order received - hope I didn't miss anyone):
"Jeffrey K. Pado" <jkp@cdicad.com>
Jochen Bern <bern@TI.Uni-Trier.DE>
djohnson@nbserv1.dseg.ti.com (Danny Johnson)
Ian MacPhedran <Ian_MacPhedran@engr.USask.Ca>
"Sergey Mokryshev" <mokr@child.ru>
Andrew Mitchell <afm@colltech.com>
Jim Harmon <jharmon@telecnnct.com>
miquel@proton.uab.es (Miquel Cabanas. BBM-UAB)
Mark Baldwin <mark.baldwin@aur.alcatel.com>
-art
This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:12:38 CDT