Subject: Re: Must every packet have a creating socket?

From: Andi Kleen <[email-masked]>
Date: Fri, 22 Apr 2005 13:39:46 +0200

Rick Jones <[email-masked]> writes:

>> Can I think that every packet (e.g. IP packet) must
>> have a corresponding creating socket? (i.e. Must every
>> packet be created by a socket?)
>
> No.  ICMP messages come to mind - although I _suppose_ that since
> those are in response to other traffic, you could claim it was in
> response to something sent from a "socket" or "endpoint" - depends on
> how far away you consider it to still be  from a socket.

Actually Linux has kernel private sockets for ICMP.
Very old Linux didnt, but it required ugly special cases
in the transmit path, so it was removed.

-Andi