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/* packet-redback.c
*
* $Id$
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
*
* Start of RedBack SE400/800 tcpdump trace disassembly
* Copyright 2005-2007 Florian Lohoff <flo@rfc822.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <glib.h>
#include <epan/packet.h>
#include <epan/etypes.h>
#include <epan/prefs.h>
#include <epan/addr_resolv.h>
#include "packet-ip.h"
static int proto_redback = -1;
static gint ett_redback = -1;
static dissector_handle_t ipv4_handle;
static dissector_handle_t eth_handle;
static dissector_handle_t clnp_handle;
static dissector_handle_t arp_handle;
static dissector_handle_t ppp_handle;
/* wrapper for passing the PIC type to the generic ATM dissector */
static void
dissect_redback(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
guint8 l3off, dataoff, proto;
guint32 context, flags;
guint64 circuit;
guint16 length;
proto_item *ti,*tisub;
proto_tree *subtree = NULL;
tvbuff_t *next_tvb;
context = tvb_get_ntohl(tvb, 0);
flags = tvb_get_ntohl(tvb, 4);
circuit = tvb_get_ntoh64(tvb, 8);
length = tvb_get_ntohs(tvb, 16);
proto = (guint8) tvb_get_ntohs(tvb, 18);
l3off = (guint8) tvb_get_ntohs(tvb, 20);
dataoff = (guint8) tvb_get_ntohs(tvb, 22);
ti = proto_tree_add_text(tree, tvb, 0, length, "Redback");
subtree = proto_item_add_subtree(ti, ett_redback);
tisub = proto_tree_add_text (subtree, tvb, 0, 4,
"Context: 0x%08x", context);
tisub = proto_tree_add_text (subtree, tvb, 4, 4,
"Flags: 0x%08x", flags);
tisub = proto_tree_add_text (subtree, tvb, 8, 8,
"Circuit: 0x%" G_GINT64_MODIFIER "x", circuit);
tisub = proto_tree_add_text (subtree, tvb, 16, 2,
"Length: %u", length);
tisub = proto_tree_add_text (subtree, tvb, 18, 2,
"Protocol: %u", proto);
tisub = proto_tree_add_text (subtree, tvb, 20, 2,
"Layer3 Offset: %u", l3off);
tisub = proto_tree_add_text (subtree, tvb, 22, 2,
"Data Offset: %u", dataoff);
/* Mark the gap as "Data" for now */
if (dataoff > l3off) {
proto_tree_add_text (subtree, tvb, 24, l3off-24, "Data (%d bytes)", l3off-24);
}
switch(proto) {
case 0x01:
/*
* IP - We assume IPv6 has a different protocol although
* i might be wrong - Havent seen any traces
*/
next_tvb = tvb_new_subset(tvb, dataoff, -1, -1);
call_dissector(ipv4_handle, next_tvb, pinfo, tree);
break;
case 0x02:
/*
* Most of the time i have seen this protocol type
* as 802.3 Ethernet containing CLNP for ISIS.
*
* Sometimes the 802.3 header is missing and the packet
* seems to be CLNP anyway. Dissecting this shows
* a broken packet for an unknown reason.
*
*/
next_tvb = tvb_new_subset(tvb, l3off, -1, -1);
if (dataoff > l3off) {
call_dissector(eth_handle, next_tvb, pinfo, tree);
} else {
call_dissector(clnp_handle, next_tvb, pinfo, tree);
}
break;
case 0x06:
/* HACK This is a guess - i dont know what this flag means
* but my best guess is that it means "incoming" e.g.
* the direction of the packet. In case of incoming PPP
* packets there seems to be some padding which does
* not get reflected in the l3off/dataoff
*/
if (flags & 0x00400000) {
next_tvb = tvb_new_subset(tvb, l3off, -1, -1);
} else {
proto_tree_add_text (subtree, tvb, l3off, 4, "Unknown Data (%d bytes)", 4);
next_tvb = tvb_new_subset(tvb, l3off+4, -1, -1);
}
if (l3off == dataoff) {
call_dissector(ppp_handle, next_tvb, pinfo, tree);
} else {
call_dissector(eth_handle, next_tvb, pinfo, tree);
}
break;
case 0x03: /* Unicast Ethernet tx - Seen with PPPoE PADO */
case 0x04: /* Unicast Ethernet rx - Seen with ARP */
case 0x08: /* Broadcast Ethernet rx - Seen with PPPoE PADI */
next_tvb = tvb_new_subset(tvb, l3off, -1, -1);
call_dissector(eth_handle, next_tvb, pinfo, tree);
break;
default:
tisub = proto_tree_add_text (subtree, tvb, 24, length-24,
"Unknown Protocol Data %u", proto);
break;
}
return;
}
void
proto_register_redback(void)
{
static gint *ett[] = {
&ett_redback,
};
proto_redback = proto_register_protocol("Redback", "Redback", "redback");
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_redback(void)
{
dissector_handle_t redback_handle;
ipv4_handle = find_dissector("ip");
eth_handle = find_dissector("eth_withoutfcs");
clnp_handle = find_dissector("clnp");
arp_handle = find_dissector("arp");
ppp_handle = find_dissector("ppp");
redback_handle = create_dissector_handle(dissect_redback, proto_redback);
dissector_add("wtap_encap", WTAP_ENCAP_REDBACK, redback_handle);
}
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