lkml.org 
[lkml]   [2004]   [Dec]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: bind() udp behavior 2.6.8.1
>sorry "closed" was the wrong term here.  We are using a PIX Firewall
>Module and it keeps a state table of all connections (tcp and udp).
>Thus when a new udp connection comes in with same high numbered source

UDP does not know connections. As such, _nobody_ can tell whether an UDP
packet belongs to a logically existing "connection" or not.

>port and the firewall has not removed that connection from its state
>table, the firewall drops the packet. The firewall needs about 60ms in
>order to clear that connection from the state table, so if a second udp
>request with the same high number port/ip comes thru before the firewall
>clears the connection from the state table, it will drop the connection
>(which is what we are seeing).
>
>FreeBSD seems to increment future udp requests which prevents this
>problem. It just seems strange that the kernel would not randomize or
>increment these source ports for udp requests.

The kernel does not have problems with UDP, it's probably your firewall.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 14:08    [W:2.941 / U:0.260 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site