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/* packet-vntag.c
*
* $Id$
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include <glib.h>
#include <epan/packet.h>
#include <epan/etypes.h>
void proto_register_vntag(void);
void proto_reg_handoff_vntag(void);
static dissector_handle_t ethertype_handle;
static int proto_vntag = -1;
static int hf_vntag_etype = -1;
/* static int hf_vntag_len = -1; */
static int hf_vntag_trailer = -1;
static gint ett_vntag = -1;
static void
dissect_vntag(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
guint16 encap_proto;
proto_tree *vntag_tree = NULL;
ethertype_data_t ethertype_data;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "VNTAG");
col_clear(pinfo->cinfo, COL_INFO);
if (tree) {
proto_item *ti = proto_tree_add_item(tree, proto_vntag, tvb, 0, 4, ENC_NA);
vntag_tree = proto_item_add_subtree(ti, ett_vntag);
/* XXX, 4 bytes of data */
/* from scapy (http://hg.secdev.org/scapy-com/rev/37acec891993) GPLv2:
BitField("dir", 0, 1),
BitField("ptr", 0, 1),
BitField("dst", 0, 14),
BitField("looped", 0, 1),
BitField("r", 0, 1),
BitField("version", 0, 2),
BitField("src", 0, 12) ]
*/
/* another: http://www.definethecloud.net/access-layer-network-virtualization-vn-tag-and-vepa */
}
encap_proto = tvb_get_ntohs(tvb, 4);
/* copied from packet-vlan.c do we need it also for VNTAG? */
#if 0
if (encap_proto <= IEEE_802_3_MAX_LEN) {
gboolean is_802_2;
/* Is there an 802.2 layer? I can tell by looking at the first 2
bytes after the VLAN header. If they are 0xffff, then what
follows the VLAN header is an IPX payload, meaning no 802.2.
(IPX/SPX is they only thing that can be contained inside a
straight 802.3 packet, so presumably the same applies for
Ethernet VLAN packets). A non-0xffff value means that there's an
802.2 layer inside the VLAN layer */
is_802_2 = TRUE;
/* Don't throw an exception for this check (even a BoundsError) */
if (tvb_length_remaining(tvb, 4) >= 2) {
if (tvb_get_ntohs(tvb, 4) == 0xffff)
is_802_2 = FALSE;
}
dissect_802_3(encap_proto, is_802_2, tvb, 4, pinfo, tree, vntag_tree, hf_vntag_len, hf_vntag_trailer, 0);
} else {
#endif
ethertype_data.etype = encap_proto;
ethertype_data.offset_after_ethertype = 6;
ethertype_data.fh_tree = vntag_tree;
ethertype_data.etype_id = hf_vntag_etype;
ethertype_data.trailer_id = hf_vntag_trailer;
ethertype_data.fcs_len = 0;
call_dissector_with_data(ethertype_handle, tvb, pinfo, tree, ðertype_data);
#if 0
}
#endif
}
void
proto_register_vntag(void)
{
static hf_register_info hf[] = {
{ &hf_vntag_etype,
{ "Type", "vntag.etype", FT_UINT16, BASE_HEX, VALS(etype_vals), 0x0, NULL, HFILL }
},
#if 0
{ &hf_vntag_len,
{ "Length", "vntag.len", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }
},
#endif
{ &hf_vntag_trailer,
{ "Trailer", "vntag.trailer", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }
}
};
static gint *ett[] = {
&ett_vntag
};
proto_vntag = proto_register_protocol("VN-Tag", "VNTAG", "vntag");
proto_register_field_array(proto_vntag, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
}
void
proto_reg_handoff_vntag(void)
{
dissector_handle_t vntag_handle;
/* XXX, add 0x8926 define to epan/etypes.h && etype_vals */
vntag_handle = create_dissector_handle(dissect_vntag, proto_vntag);
dissector_add_uint("ethertype", 0x8926, vntag_handle);
ethertype_handle = find_dissector("ethertype");
}
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