Hello all,
I'm running postfix-2.9.6 on Ubuntu Server 12.04 LTS amd64.
I recently ran across a bug in postfix's milter implementation, shortly
after switching the server it was running on from sendmail to postfix.
This milter removes recipients that aren't in a whitelist, so I keep a
list of recipients in the RCPT TO method, and then in EOB (which is the
only place you can modify the mail) I loop through them and call delete
recipient on them. This works fine to stop mail from going to
u...@example.org, but fails to stop mail from going to u...@example.org,
or u...@example.org (case difference anywhere, in local part or
domain). The problem is the name sent to the rcpt method is always
lowercase, regardless of what is sent in, but the delete recipient
method appears to be case-sensitive. So if mail is to u...@example.org,
delete(u...@example.org) works, but if mail is u...@example.org, postfix
tells me it's u...@example.org, and delete(u...@example.org) does not
work. But if I hard-code into the milter delete(u...@example.org), the
recipient is removed.
It's worth it to note that sendmail sends the name to the rcpt method in
whatever case it is supposed to use, so I believe postfix should too.
I got the postfix source code and found the code that sends this
information, but I can't debug anything because I can't figure out how
to make that code print to any logs. In src/milter/milter.c and
src/milter/milter8.c, there are plenty of:
if (msg_verbose)
msg_info("%s: skip milter %s", myname, milter->m.name);
type statements, but even if I comment out if(msg_verbose), recompile
and install, I can't find a message like that anywhere. I've sent
'-vvvvv' to postfix itself, and to every service in master.cf including
smtp,smtpd,cleanup and all the others in there by default on Ubuntu
12.04 LTS, which causes many verbose messages to be in the log, but none
from any milter code as far as I can see.
So this message is half bug report, and half asking how to properly
debug the milter code so I can submit a patch. Sorry for the length and
if there are any questions I can answer let me know.
Thanks much!
