Sender Rewriting Scheme in Python
This web page is written by Stuart D. Gathman
and
sponsored by
Business Management Systems, Inc.
Last updated Mar 23, 2004
This is a Python implementation of
the Sender Rewriting Scheme.
It is a fairly direct translation of the
draft implementation in Perl
by Shevek. It includes a test suite, which currently checks four
levels of forwarding and subsequent reversal for the Guarded, DB, and
Reversible implementations.
- This package includes scripts to be used as sendmail maps. See
sendmail integration
for instructions on incorporating SRS into
sendmail.cf,
substituting envfrom2srs.py and srs2envtol.py
for the perl scripts.
- SRS.Daemon.Daemon() provides a simple socket daemon suitable
for use with the Exim mailer.
Sendmail integration
Add the following lines to your /etc/mail/sendmail.mc (RedHat /
Fedora):
#
# File listing domains we do not SRS encode for when sending to
#
define(`NO_SRS_FILE',`/etc/mail/no-srs-mailers')dnl
#
# Uncomment the following if you do not wish to SRS encode mail from
# local domains. Only non-local domains need to be SRS encoded to
# satisfy SPF. But encoding all outgoing mail can detect bounce forgeries.
#
dnl define(`NO_SRS_FROM_LOCAL')dnl
#
HACK(`pysrs',`mydomain.com')dnl
- NO_SRS_FILE is the path of a file containing the recipient
MTA's for which you won't do SRS (typically, primary MXes for
who you are secondary). Just leave this away, if you are
secondary for nobody. The no-srs-mailers file is a simple text
file which has one recipient MTA per line.
- SRS_DOMAIN is the domain that your SRS addresses bear (i.e. if
your SRS addresses are srs0=mumble-jumble-toto@mydomain.com,
then the SRS_DOMAIN domain is mydomain.com)
- NO_SRS_FROM_LOCAL : if this is set (define line present), then
no SRS is done if sender is local (i.e. his domain is in
/etc/mail/local-host-names)
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