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From: Ignoramus22979 on 6 May 2010 16:05
I would like to know if there is some "dummy" program that looks to
the outside worls as a MTA, but in reality all it does is accept
incoming mail and simply disregards it (drops to bit bucket).

I know that sendmail can be configured to do what I want, but it is a
lot of overhead given what I want.

Thanks

i
From: Grant Taylor on 6 May 2010 18:23
Ignoramus22979 wrote:
> I would like to know if there is some "dummy" program that looks to
> the outside worls as a MTA, but in reality all it does is accept
> incoming mail and simply disregards it (drops to bit bucket).

I'd look at a honey pot or spam detection program to do this.

If you aren't actually doing any thing with the mail, it should be
trivial to write such a program. The SMTP state machine is not
difficult, and you could have (x)inetd spawn an instance of your program
for each connection.



Grant. . . .
From: Claus Aßmann on 6 May 2010 20:10
Ignoramus22979 wrote:
> I would like to know if there is some "dummy" program that looks to
> the outside worls as a MTA, but in reality all it does is accept
> incoming mail and simply disregards it (drops to bit bucket).

Several MTA distributions come with test suites and contain
smtp sinks, e.g., postfix, MeTA1, and probably others.
From: David F. Skoll on 7 May 2010 07:00
Ignoramus22979 wrote:

> I would like to know if there is some "dummy" program that looks to
> the outside worls as a MTA, but in reality all it does is accept
> incoming mail and simply disregards it (drops to bit bucket).

Here's one in Perl. Run it from (x)inetd.

Regards,

David.

#!/usr/bin/perl -w

# Null SMTP server. Accepts and throws away everything on stdin.
# Run it via inetd.

print "220 /dev/null SMTP Ready\n";
my $in_data = 0;
$| = 1;
while(<>) {
$in_data = 0 if ($in_data && /^\.\r?$/);
next if $in_data;
if (/^QUIT\r?$/i) {
print "221 didn't even know you were here\n";
last;
}
if (/^DATA/i) {
print "350 sure, but I will throw it away\n";
$in_data = 1;
next;
}
print "250 sent to /dev/null as planned\n";
}
From: wisdomkiller & pain on 7 May 2010 13:49
Ignoramus22979 wrote:

> I would like to know if there is some "dummy" program that looks to
> the outside worls as a MTA, but in reality all it does is accept
> incoming mail and simply disregards it (drops to bit bucket).
>
> I know that sendmail can be configured to do what I want, but it is a
> lot of overhead given what I want.
>
A good one is smtarpit - it is intended for just that purpose, to trap
spammers by delayed smtp negotiation sequences and block their outgoing
ports and ressources.
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