This isn't so much a bug as a potential addition. I applied the gentoo-qmail-1.03-r16-mfcheck.3.patch to the qmail source with all the other patches already applied from -r13. As you probably know, that patch works just fine except for qmail-smtpd.c. The URL I submitted is a diff for just qmail-smtpd.c that adds the mfcheck code to the r13 qmail-smtpd.c file. I have applied this patch and been testing it on a pretty active mail server for a over a day now. I've also using telnet to try connecting with bad domain names and I am getting booted. I consider this functionality critical to qmail. I know it is a small window, but between Midnight last night at 8:00am this morning spamassassin caught 60 spam messages. The night before it caught 300 messages, the night before that 268 messages, the night before that 388 messages. Rejecting fake domains seams to greatly decrease the spam I see. Anyway, I hope this helps you guys out in some way. I'd like to see the mfcheck patch added to qmail because I'm tired of having to manually apply all those patches. Reproducible: Always Steps to Reproduce:
Created attachment 51360 [details, diff] qmail-stmpd.c patch file for qmail-1.03-r13 and mfcheck The other parts of gentoo-qmail-1.03-r16-mfcheck.3.patch must be applied as well... I'm working on a more complete solution (aka a patch with everything..).
Spammers are too smart for that still. Between 2005-02-16 10:00:45.734354500 and 2005-02-16 11:05:16.910481500 (yes, that's a window of just 65 minutes), my mailserver has rejected 1034 messages due to non-existant recipients (SMTP level). SpamAssassin has considered a further 644 messages, of which 591 were classified as spam. For the mail personally directed to me, SpamAssassin missed two spams today. This is running with -r16 with mfcheck AND my custom modification that uses iptables to ignore any host that sends me more than 2 non-existant recipient spams in a minute (the numbers used to be 10x larger before I started doing this). We will NOT be backporting the work of -r16 to older builds. We are still working on -r16, incl. getting qmail-spp fully into place (which provides a LOT more SMTP level checks, incl. doing mfcheck better with whois records).
I guess I wasn't clear with why I posted this. I was actually expecting you to backport this. I actually looked into this because your r16-mfcheck patch fails. These fixes work on r16 for me as well.
