DISCLAIMER: There is no guarantee that I know what I am talking about. Use at your own risk.
This page is about callahead-milter that I cooked up.

Nov 16, 2009, callahead-milter v0.08

Packaged compile fixes in a tarball with some instructions and some minor fixes.

Feb 4, 2007, callahead-milter v0.07

Bugfixes for getservbyname() multithread leak by introducing the -yY command line args. This release defaults to turning off the _FFR_MILTER_REWRITE and _FFR_MILTER_SM_MAP features. To turn them on, use -D_FFR_MILTER_REWRITE=1 and -D_FFR_MILTER_SM_MAP=1 on the compile command line.

In lieu of any real documentaion, here is the updated help output.

Dec 14, 2006, callahead-milter v0.06

Bugfixes for timeout handling, and proper tempfails when that happens. This is a snapshot of code with some new features such as hostmap, but caching is still only half done. Dont try to use the caching.

Oct 18 2006, callahead-milter v0.03

Bugfixes, daemonizing. This version appears to run for at least 12 hours straight in production. Compiled with -O2 and no debugging. Command line used:

/usr/local/sbin/callahead-milter -p /var/run/sendmail/callahead-milter/sock -E -B pop3.ttec.com -H smtp2.mx.ttec.com -u -T -g -VV -z

Updated: Oct 22, 2006
Still running without any apparent leaks or errors. I suppose that means that its safe to use with its current feature set if you can get it to compile.

Oct 16 2006, callahead-milter

Future versions may be released as tarballs.

Oct 13 2006, callahead-milter

A new milter project, callahead-milter is a milter that is designed to be able to perform rcpt and sender callahead/callback smtp verification. It is designed to be able to work closely with sendmail and to do as little harm as possible.

While at version 0.01 the milter is probably completely unsuited for actual use except for those brave and hardy souls looking for adventure, at 2821 lines it was impossible to resist posting its announcement.

Compile Line any of the following: gcc -DDEBUG -g callahead-milter.v001.c -lmilter -lpthread -o callahead-milter -Wall -lresolv -lmcheck
gcc -DDEBUG -g callahead-milter.v001.c -lmilter -lpthread -o callahead-milter -Wall -lresolv
gcc -g callahead-milter.v001.c -lmilter -lpthread -o callahead-milter -Wall -lresolv
gcc -02 callahead-milter.v001.c -lmilter -lpthread -o callahead-milter -Wall -lresolv

If you are not going to take advantage of this milter's ability to utilize the milter-rrres patch's features, you must also add "-D_FFR_MILTER_REWRITE=0 -D_FFR_MILTER_SM_MAP=0" to the compile line.

It is not expected that this version will actually be usuable in any sort of production environment. This is a proof of concept.

Of the notable missing features, aside from full testing and a real build environment, is the lack of smtp connection and verification result caching. That is expected in future, usuable versions.

At this time, it is unexpected that you will be able to compile the milter except on a recently updated testing debian gnu/linux box.

In lieu of any real documentaion, here is the help output.

Applicable licenses and copyright information.

Future versions will be released as tarballs.

Copious troubleshooting can be output by compiling with -DDEBUG using -VVVVV -L logfile.
If you could isolate the problem to a single session reproduced with "sendmail -bs -Am" that would be considerate.
gdb bt output is also welcome.

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