Greg Moeller <[EMAIL PROTECTED]> wrote:
> The header on his Email looks like:
> From: <>
[...]
> Is an utterly null From line allowed?
Yes. The From: header doesn't even have to exist in a message.
Null envelope senders are also allowed, and in some cases (bounce messages)
required.
> From a normal modem, this guy has managed to get our queue to:
> bash-2.02# /var/qmail/bin/qmail-qstat
> messages in queue: 83261
> messages in queue but not yet preprocessed: 4
> (and this is with a rather powerful multi processor sparc)
>
> What can be done about this sort of thing?
If he's using a static envelope sender (which isn't null), add it to
/var/qmail/control/badmailfrom, and qmail will reject mail from that
envelope sender.
If you know the IP address he's connecting from, add the line
[IP of spammer]:deny
to the tcprules file which controls your qmail-smtpd and recompile the
cdb file (using tcprules). See the documentation for tcpserver, and the
script which starts qmail-smtpd on your system, for details.
> It's really annoying that one idiot with a modem can destroy a rather large
> Qmail system.
It's a design flaw in SMTP. djb's IM2000 proposals would eliminate the
problem.
> (yes, I lock out his IP, but he just dials in and gets another one)
The proper solution here is to contact (frequently, noisily, and until his
account is dead) the abuse department of the ISP he's connecting from.
Charles
--
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Charles Cazabon <[EMAIL PROTECTED]>
GPL'ed software available at: http://www.qcc.sk.ca/~charlesc/software/
Any opinions expressed are just that -- my opinions.
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