On Sat, Jun 09, 2001 at 08:52:36AM +0800, Rebecca wrote:
> using ipchains, im only allowing ports 25,53,110,143 but my log shows
> that the senders mail server is probing port 113 (auth). though i
> receive the emails, the packets for 113 is being denied. should i allow
> this? what are the complications?
Port 113 is auth, a service where your server will tell the other mail server
the username of the one making the connection. Take a look at SMTP headers,
you'll find stuff like root@server - the 'root' came from the auth server.
Nowadays it's safe to filter it, make sure you reject it and send a RST
for "Connection refused"; don't make it hang by just dropping the packets.
--
http://www.internet.org.ph .PH is PHilippines not PHone!
Philippine Internet Resources http://www.phildac.org
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