netdev - How to find I/F to destination

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 04 May 2007 13:48:48 +0100
From:	David Howells <dhowells@...hat.com>
To:	netdev@...r.kernel.org
cc:	Patrick McHardy <kaber@...sh.net>
Subject: How to find I/F to destination

Hi,

I would like to determine through which interface packets sent to a particular
UDP destination will go through, and so determine the MTU size for that
interface.  Can anyone suggest a good way of doing this from within the
kernel?

Doing this will permit AF_RXRPC to obtain a better initial guess as to the
maximum size of the packets that can be sent that way.

I could use the code Patrick gave me to allow AFS to iterate through all the
interfaces and then pick the smallest MTU, but that seems wrong somehow -
though it probably will result in the correct answer 99% of the time.

David
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html