2.9.17 Forward rule that I don't understand. Bug maybe?

blankman · Tue Mar 14, 2006 2:18 am

Hello All:
So, I have a rule in my forward chain that I can't figure out.

6   chain=forward dst-address=172.31.5.252 protocol=tcp action=jump jump-target=chat

19:00:32 firewall,info before chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:57208->172.31.5.252:443, len 60
19:00:32 firewall,info ssh chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:57208->172.31.5.252:443, len 60
19:00:32 firewall,info ssl chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:57208->172.31.5.252:443, len 60
19:00:32 firewall,info chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:57208->172.31.5.252:443, len 60

This is what prints this log out:

0   chain=chat protocol=tcp action=log log-prefix="before"

 1   chain=chat dst-address=172.31.5.252 dst-port=22 action=log log-prefix="ssh"

 2   chain=chat dst-address=172.31.5.252 dst-port=443 connection-state=new action=log log-prefix="ssl"

 3   chain=chat action=log log-prefix=""

 4   chain=chat action=reject reject-with=icmp-host-unreachable

Now, maybe I am REALLY out of it, but how can both dst-ports (22,443) be matching?
Anyhelp is much appreciated

So just for the grin of it, I tried one other thing. This time both match on the port, even though it is port 23!

19:09:30 firewall,info before chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:51480->172.31.5.252:23, len 60
19:09:30 firewall,info ssh chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:51480->172.31.5.252:23, len 60
19:09:30 firewall,info ssl chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:51480->172.31.5.252:23, len 60
19:09:30 firewall,info chat: in:ether1 out:ether2, src-mac a:b:c:d:e:f, proto TCP (SYN), w.x.y.z:51480->172.31.5.252:23, len 60

Tue Mar 14, 2006 1:32 pm

It is required to specify protocol (tcp/udp) to match tcp/udp ports.

blankman · Tue Mar 14, 2006 2:14 pm

It is required to specify protocol (tcp/udp) to match tcp/udp ports.

Thanks normis. That did do it. Just for those that might want to use the search feature:

If you are using the dst-port on a firewall filter chain, the system requires you to tell it the protocol of something that "cares" about a port before it will match on your port. Thus the dst-port will only work if you have used something link tcp or udp.

Cheers all.

2.9.17 Forward rule that I don't understand. Bug maybe?

Do you know how to use the scripting function of MT?

2.9.17 Forward rule that I don't understand. Bug maybe?

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