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/* packet-erspan.c
* Routines for the disassembly of Cisco's ERSPAN protocol
*
* $Id$
*
* Copyright 2005 Joerg Mayer (see AUTHORS file)
*
* Wireshark - Network traffic analyzer
* By Gerald Combs <gerald@wireshark.org>
* Copyright 1998 Gerald Combs
*
* 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.
*/
/*
* TODO:
* Find out the Unknown values
*
* Specs:
* No real specs exist. Some general description can be found at:
* http://www.cisco.com/en/US/products/hw/routers/ps368/products_configuration_guide_chapter09186a008069952a.html
*
* For ERSPAN packets, the "protocol type" field value in the GRE header
* is 0x88BE.
*
* 0000000: d4c3 b2a1 0200 0400 0000 0000 0000 0000 <-- pcap header
* 0000010: ffff 0000
* 0000010: 7100 0000 <-- 0x71 (DLT_TYPE) = linux_cooked_capture (of course not)
* 0000010: 7507 f845 11d1 0500 <-- pcap record header
* 0000020: 7a00 0000 7a00 0000
* 0000020: 0000 030a 0000 0000 <-- unknown
* 0000030: 0000 0000
* 0000030: 0000 88be <-- GRE header
* 0000030: 1002 0001 0000 0380 <-- ERSPAN header (01: erspan-id)
* 0000040: 00d0 b7a7 7480 0015 c721 75c0 0800 4500 <-- Ethernet packet
* ...
*
*
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <glib.h>
#include <epan/packet.h>
#include <epan/greproto.h>
static int proto_erspan = -1;
static gint ett_erspan = -1;
static int hf_erspan_unknown1 = -1;
static int hf_erspan_vlan = -1;
static int hf_erspan_priority = -1;
static int hf_erspan_unknown2 = -1;
static int hf_erspan_direction = -1;
static int hf_erspan_unknown3 = -1;
static int hf_erspan_spanid = -1;
static int hf_erspan_unknown4 = -1;
#define PROTO_SHORT_NAME "ERSPAN"
#define PROTO_LONG_NAME "ER Switch Packet Analysis"
#define ERSPAN_DIRECTION_INCOMING 0
#define ERSPAN_DIRECTION_OUTGOING 1
static const value_string erspan_direction_vals[] = {
{ERSPAN_DIRECTION_INCOMING, "Incoming"},
{ERSPAN_DIRECTION_OUTGOING, "Outgoing"},
{0, NULL},
};
static dissector_handle_t ethnofcs_handle;
static void
dissect_erspan(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_item *ti;
proto_tree *erspan_tree = NULL;
tvbuff_t *eth_tvb;
guint32 offset = 0;
col_set_str(pinfo->cinfo, COL_PROTOCOL, PROTO_SHORT_NAME);
col_set_str(pinfo->cinfo, COL_INFO, PROTO_SHORT_NAME ":");
if (tree) {
ti = proto_tree_add_item(tree, proto_erspan, tvb, offset, -1,
FALSE);
erspan_tree = proto_item_add_subtree(ti, ett_erspan);
proto_tree_add_item(erspan_tree, hf_erspan_unknown1, tvb, offset, 2,
FALSE);
proto_tree_add_item(erspan_tree, hf_erspan_vlan, tvb, offset, 2,
FALSE);
offset += 2;
proto_tree_add_item(erspan_tree, hf_erspan_priority, tvb, offset, 2,
FALSE);
proto_tree_add_item(erspan_tree, hf_erspan_unknown2, tvb, offset, 2,
FALSE);
proto_tree_add_item(erspan_tree, hf_erspan_direction, tvb, offset, 2,
FALSE);
proto_tree_add_item(erspan_tree, hf_erspan_unknown3, tvb, offset, 2,
FALSE);
proto_tree_add_item(erspan_tree, hf_erspan_spanid, tvb, offset, 2,
FALSE);
offset += 2;
proto_tree_add_item(erspan_tree, hf_erspan_unknown4, tvb, offset, 4,
FALSE);
offset += 4;
}
else {
offset += 8;
}
eth_tvb = tvb_new_subset_remaining(tvb, offset);
call_dissector(ethnofcs_handle, eth_tvb, pinfo, tree);
}
void
proto_register_erspan(void)
{
static hf_register_info hf[] = {
{ &hf_erspan_unknown1,
{ "Unknown1", "erspan.unknown1", FT_UINT16, BASE_HEX, NULL,
0xf000, NULL, HFILL }},
{ &hf_erspan_vlan,
{ "Vlan", "erspan.vlan", FT_UINT16, BASE_DEC, NULL,
0x0fff, NULL, HFILL }},
{ &hf_erspan_priority,
{ "Priority", "erspan.priority", FT_UINT16, BASE_DEC, NULL,
0xe000, NULL, HFILL }},
{ &hf_erspan_unknown2,
{ "Unknown2", "erspan.unknown2", FT_UINT16, BASE_DEC, NULL,
0x1000, NULL, HFILL }},
{ &hf_erspan_direction,
{ "Direction", "erspan.direction", FT_UINT16, BASE_DEC, VALS(erspan_direction_vals),
0x0800, NULL, HFILL }},
{ &hf_erspan_unknown3,
{ "Unknown3", "erspan.unknown3", FT_UINT16, BASE_DEC, NULL,
0x0400, NULL, HFILL }},
{ &hf_erspan_spanid,
{ "SpanID", "erspan.spanid", FT_UINT16, BASE_DEC, NULL,
0x03ff, NULL, HFILL }},
{ &hf_erspan_unknown4,
{ "Unknown4", "erspan.unknown4", FT_BYTES, BASE_NONE, NULL,
0, NULL, HFILL }},
};
static gint *ett[] = {
&ett_erspan,
};
proto_erspan = proto_register_protocol(PROTO_LONG_NAME,
PROTO_SHORT_NAME, "erspan");
proto_register_field_array(proto_erspan, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_erspan(void)
{
dissector_handle_t erspan_handle;
ethnofcs_handle = find_dissector("eth_withoutfcs");
erspan_handle = create_dissector_handle(dissect_erspan, proto_erspan);
dissector_add("gre.proto", GRE_ERSPAN, erspan_handle);
}
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