Request: defining a protocol number for SS7 in if_ether.h

From: Thomas Steffen
Date: Mon Aug 08 2005 - 09:17:19 EST


I would like to reserve a protocol number for SS7 MTP2 in the file
if_ether.h. The reason is that I want to include SS7 packages in a
linux cooked trace. There are already several "private" numbers in
this file that represent non-ethernet protocols, so I think this is
the right place for it.

I do not intend to put SS7 tracing support into the Linux kernel. This
would be up to manufacturer of an SS7 card and driver. However, I
intend to extend Ethereal so that it can handle this encapsulation
(the trace file is generated in user space). Once an SS7 driver
supports the Linux tracing interface, it could immediately be used
with Ethereal.

Because this only the reserves a new number, there is no danger of
breaking anything. The only cost of the patch is that it uses up one
protocol number, but since there is a range of 1500 unused protocol
number, I cannot imagine a shortage any time soon.

So would it possible to include this? I also had an discussion on the
Ethereal develeoper list about it, and this seems to be the only
elegant way of capturing SS7 packets and Ethernet frames in one trace.

Thomas (not on the list, so please drop me a copy if you have any comments)
--- include/linux/if_ether.h.org 2005-08-08 16:09:47.000000000 +0200
+++ include/linux/if_ether.h 2005-08-08 16:09:35.000000000 +0200
@@ -92,6 +92,7 @@
#define ETH_P_ECONET 0x0018 /* Acorn Econet */
#define ETH_P_HDLC 0x0019 /* HDLC frames */
#define ETH_P_ARCNET 0x001A /* 1A for ArcNet :-) */
+#define ETH_P_MTP2 0x001B /* MTP2 (bottom of the SS7 stack) */

/*
* This is an Ethernet frame header.