wireshark/epan/dissectors/packet-ieee8021ah.c

447 lines
15 KiB
C

/* packet-ieee8021ah.c
* Routines for 802.1ah ethernet header disassembly
*
* $Id$
*
* 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/addr_resolv.h>
#include "packet-ieee8023.h"
#include "packet-ieee8021ah.h"
#include "packet-ipx.h"
#include "packet-llc.h"
#include "packet-vlan.h"
#include <epan/etypes.h>
#include <epan/prefs.h>
void proto_reg_handoff_ieee8021ah(void);
void dissect_ieee8021ah_common(tvbuff_t *tvb, packet_info *pinfo,
proto_tree *tree, proto_tree *parent, int tree_index);
/* GLOBALS ************************************************************/
/* ethertype for 802.1ah tag - encapsulating an Ethernet packet */
static unsigned int ieee8021ah_ethertype = ETHERTYPE_IEEE_802_1AH;
static int proto_ieee8021ah = -1;
static int proto_ieee8021ad = -1;
/* dot1ad B-tag fields */
static int hf_ieee8021ad_priority = -1;
static int hf_ieee8021ad_cfi = -1;
static int hf_ieee8021ad_id = -1;
static int hf_ieee8021ad_svid = -1;
static int hf_ieee8021ad_cvid = -1;
/* dot1ah C-tag fields */
static int hf_ieee8021ah_priority = -1;
static int hf_ieee8021ah_drop = -1; /* drop eligibility */
static int hf_ieee8021ah_nca = -1; /* no customer addresses (c_daddr & c_saddr are 0) */
static int hf_ieee8021ah_res1 = -1; /* 2 bits reserved; ignored on receive */
static int hf_ieee8021ah_res2 = -1; /* 2 bits reserved; delete frame if non-zero */
static int hf_ieee8021ah_isid = -1; /* I-SID */
static int hf_ieee8021ah_c_daddr = -1; /* encapsulated customer dest addr */
static int hf_ieee8021ah_c_saddr = -1; /* encapsulated customer src addr */
static int hf_ieee8021ah_etype = -1;
static int hf_ieee8021ah_len = -1;
static int hf_ieee8021ah_trailer = -1;
static gint ett_ieee8021ah = -1;
static gint ett_ieee8021ad = -1;
/* FUNCTIONS ************************************************************/
void
capture_ieee8021ah(const guchar *pd, int offset, int len, packet_counts *ld)
{
guint16 encap_proto;
if (!BYTES_ARE_IN_FRAME(offset, len, IEEE8021AH_LEN + 1)) {
ld->other++;
return;
}
encap_proto = pntohs( &pd[offset + IEEE8021AH_LEN - 2] );
if (encap_proto <= IEEE_802_3_MAX_LEN) {
if ( pd[offset + IEEE8021AH_LEN] == 0xff
&& pd[offset + IEEE8021AH_LEN + 1] == 0xff ) {
capture_ipx(ld);
}
else {
capture_llc(pd, offset + IEEE8021AH_LEN,len,ld);
}
}
else {
capture_ethertype(encap_proto, pd, offset + IEEE8021AH_LEN, len, ld);
}
}
/* Dissector *************************************************************/
static
void
dissect_ieee8021ad(tvbuff_t *tvb, packet_info *pinfo,
proto_tree *tree)
{
proto_tree *ptree = NULL;
proto_tree *tagtree = NULL;
guint32 tci, ctci;
guint16 encap_proto;
proto_tree *volatile ieee8021ad_tree;
proto_tree *volatile ieee8021ad_tag_tree;
int proto_tree_index;
tvbuff_t *volatile next_tvb = NULL;
/* set tree index */
proto_tree_index = proto_ieee8021ad;
/* add info to column display */
col_set_str(pinfo->cinfo, COL_PROTOCOL, "802.1ad");
col_clear(pinfo->cinfo, COL_INFO);
tci = tvb_get_ntohs( tvb, 0 );
if (check_col(pinfo->cinfo, COL_INFO)) {
col_add_fstr(pinfo->cinfo, COL_INFO,
"PRI: %d DROP: %d ID: %d",
(tci >> 13), ((tci >> 12) & 1), (tci & 0xFFF));
}
/* create the protocol tree */
ieee8021ad_tree = NULL;
if (tree) {
ptree = proto_tree_add_item(tree, proto_tree_index, tvb, 0, IEEE8021AD_LEN, ENC_NA);
ieee8021ad_tree = proto_item_add_subtree(ptree, ett_ieee8021ad);
}
encap_proto = tvb_get_ntohs(tvb, IEEE8021AD_LEN - 2);
/* If it's a 1ah frame, create subtree for B-Tag, rename overall
tree to 802.1ah, pass to 1ah dissector */
if (encap_proto == ETHERTYPE_IEEE_802_1AH) {
if (tree) {
tagtree = proto_tree_add_item(ptree, proto_tree_index, tvb, 0, 2, ENC_NA);
ieee8021ad_tag_tree = proto_item_add_subtree(tagtree, ett_ieee8021ad);
/* add fields */
proto_tree_add_uint(ieee8021ad_tag_tree, hf_ieee8021ad_priority, tvb,
0, 1, tci);
proto_tree_add_uint(ieee8021ad_tag_tree, hf_ieee8021ad_cfi, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ad_tag_tree, hf_ieee8021ad_id, tvb, 0, 2, tci);
/* set label of B-tag subtree */
proto_item_set_text(ieee8021ad_tag_tree, "B-Tag, B-VID: %d", tci & 0x0FFF);
}
next_tvb = tvb_new_subset_remaining(tvb, IEEE8021AD_LEN);
if (ptree) {
/* add bvid to label */
proto_item_set_text(ptree, "IEEE 802.1ah, B-VID: %d", tci & 0x0FFF);
dissect_ieee8021ah_common(next_tvb, pinfo, ptree, tree, proto_tree_index);
}
else {
dissect_ieee8021ah_common(next_tvb, pinfo, tree, NULL, proto_tree_index);
}
return;
} else if (encap_proto == ETHERTYPE_IEEE_802_1AD) {
/* two VLAN tags (i.e. Q-in-Q) */
ctci = tvb_get_ntohs(tvb, IEEE8021AD_LEN);
if (tree) {
/* add fields */
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_priority, tvb,
0, 1, tci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_cfi, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_svid, tvb, 0, 2, tci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_priority, tvb,
IEEE8021AD_LEN, 1, ctci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_cfi, tvb,
IEEE8021AD_LEN, 1, ctci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_cvid, tvb, IEEE8021AD_LEN,
2, ctci);
}
proto_item_set_text(ptree, "IEEE 802.1ad, S-VID: %d, C-VID: %d", tci & 0x0FFF,
ctci & 0x0FFF);
/* 802.1ad tags are always followed by an ethertype; call next
dissector based on ethertype */
encap_proto = tvb_get_ntohs(tvb, IEEE8021AD_LEN * 2 - 2);
ethertype(encap_proto, tvb, IEEE8021AD_LEN * 2, pinfo, tree, ieee8021ad_tree,
hf_ieee8021ah_etype, hf_ieee8021ah_trailer, 0);
} else {
/* Something else (shouldn't really happen, but we'll support it anyways) */
if (tree) {
/* add fields */
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_priority, tvb,
0, 1, tci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_cfi, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ad_tree, hf_ieee8021ad_id, tvb, 0, 2, tci);
}
/* label should be 802.1ad not .1ah */
proto_item_set_text(ptree, "IEEE 802.1ad, ID: %d", tci & 0x0FFF);
/* 802.1ad tags are always followed by an ethertype; call next
dissector based on ethertype */
ethertype(encap_proto, tvb, IEEE8021AD_LEN, pinfo, tree, ieee8021ad_tree,
hf_ieee8021ah_etype, hf_ieee8021ah_trailer, 0);
}
}
void
dissect_ieee8021ah_common(tvbuff_t *tvb, packet_info *pinfo,
proto_tree *tree, proto_tree *parent, int tree_index) {
guint32 tci;
guint16 encap_proto;
proto_tree *ptree;
proto_tree *volatile ieee8021ah_tag_tree;
/* for parsing out ethernet addrs */
const guint8 *src_addr, *dst_addr;
tci = tvb_get_ntohl( tvb, 0 );
if (check_col(pinfo->cinfo, COL_INFO)) {
col_add_fstr(pinfo->cinfo, COL_INFO,
"PRI: %d Drop: %d NCA: %d Res1: %d Res2: %d I-SID: %d",
(tci >> 29), ((tci >> 28) & 1), ((tci >> 27) & 1),
((tci >> 26) & 1), ((tci >> 24) & 3), tci & IEEE8021AH_ISIDMASK);
}
/* create the protocol tree */
ptree = NULL;
ieee8021ah_tag_tree = NULL;
if (tree) {
/* 802.1ah I-Tag */
ptree = proto_tree_add_item(tree, tree_index, tvb, 0, 4, ENC_NA);
ieee8021ah_tag_tree = proto_item_add_subtree(ptree, ett_ieee8021ah);
/* add fields */
proto_tree_add_uint(ieee8021ah_tag_tree, hf_ieee8021ah_priority, tvb,
0, 1, tci);
proto_tree_add_uint(ieee8021ah_tag_tree, hf_ieee8021ah_drop, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ah_tag_tree, hf_ieee8021ah_nca, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ah_tag_tree, hf_ieee8021ah_res1, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ah_tag_tree, hf_ieee8021ah_res2, tvb, 0, 1, tci);
proto_tree_add_uint(ieee8021ah_tag_tree, hf_ieee8021ah_isid, tvb, 1, 3, tci);
proto_item_set_text(ieee8021ah_tag_tree, "I-Tag, I-SID: %d",
tci & IEEE8021AH_ISIDMASK);
/* ensure size of tag */
tvb_ensure_bytes_exist(tvb, 4, 12);
/* parse out IP addrs */
dst_addr = tvb_get_ptr(tvb, 4, 6); /* safe to use this function? */
src_addr = tvb_get_ptr(tvb, 10, 6);
proto_tree_add_ether(tree, hf_ieee8021ah_c_daddr,
tvb, 4, 6, dst_addr);
proto_tree_add_ether(tree, hf_ieee8021ah_c_saddr,
tvb, 10, 6, src_addr);
/* add text to 802.1ad label */
if (parent) {
proto_item_append_text(tree, ", I-SID: %d, C-Src: %s (%s), C-Dst: %s (%s)",
tci & IEEE8021AH_ISIDMASK, get_ether_name(src_addr),
ether_to_str(src_addr), get_ether_name(dst_addr),
ether_to_str(dst_addr));
}
}
encap_proto = tvb_get_ntohs(tvb, IEEE8021AH_LEN - 2);
/* 802.1ah I-tags are always followed by an ethertype; call next
dissector based on ethertype */
/* If this was preceded by a 802.1ad tag, must pass original tree
to next dissector, not 802.1ad tree */
if (parent) {
ethertype(encap_proto, tvb, IEEE8021AH_LEN, pinfo, parent, tree,
hf_ieee8021ah_etype, hf_ieee8021ah_trailer, 0);
}
else {
ethertype(encap_proto, tvb, IEEE8021AH_LEN, pinfo, tree, tree,
hf_ieee8021ah_etype, hf_ieee8021ah_trailer, 0);
}
}
static
void
dissect_ieee8021ah(tvbuff_t *tvb, packet_info *pinfo,
proto_tree *tree)
{
proto_tree *ptree;
guint32 tci;
proto_tree *volatile ieee8021ah_tree;
int proto_tree_index;
/* set tree index */
proto_tree_index = proto_ieee8021ah;
/* add info to column display */
col_set_str(pinfo->cinfo, COL_PROTOCOL, "802.1ah");
col_clear(pinfo->cinfo, COL_INFO);
tci = tvb_get_ntohl( tvb, 0 );
if (check_col(pinfo->cinfo, COL_INFO)) {
col_add_fstr(pinfo->cinfo, COL_INFO,
"PRI: %d Drop: %d NCA: %d Res1: %d Res2: %d I-SID: %d",
(tci >> 29), ((tci >> 28) & 1), ((tci >> 27) & 1),
((tci >> 26) & 1), ((tci >> 24) & 3), (tci & 0x00FFFFFF));
}
/* create the protocol tree */
ieee8021ah_tree = NULL;
if (tree) {
ptree = proto_tree_add_item(tree, proto_tree_index, tvb, 0, IEEE8021AH_LEN, ENC_NA);
ieee8021ah_tree = proto_item_add_subtree(ptree, ett_ieee8021ah);
dissect_ieee8021ah_common(tvb, pinfo, ieee8021ah_tree, tree, proto_tree_index);
}
}
/* Protocol Registration **************************************************/
void
proto_register_ieee8021ah(void)
{
static hf_register_info hf[] = {
{ &hf_ieee8021ah_priority, {
"Priority", "ieee8021ah.priority", FT_UINT32, BASE_DEC,
0, 0xE0000000, NULL, HFILL }},
{ &hf_ieee8021ah_drop, {
"DROP", "ieee8021ah.drop", FT_UINT32, BASE_DEC,
0, 0x10000000, NULL, HFILL }},
{ &hf_ieee8021ah_nca, {
"NCA", "ieee8021ah.nca", FT_UINT32, BASE_DEC,
0, 0x08000000, "No Customer Addresses", HFILL }},
{ &hf_ieee8021ah_res1, {
"RES1", "ieee8021ah.res1", FT_UINT32, BASE_DEC,
0, 0x04000000, "Reserved1", HFILL }},
{ &hf_ieee8021ah_res2, {
"RES2", "ieee8021ah.res2", FT_UINT32, BASE_DEC,
0, 0x03000000, "Reserved2", HFILL }},
{ &hf_ieee8021ah_isid, {
"I-SID", "ieee8021ah.isid", FT_UINT32, BASE_DEC,
0, 0x00FFFFFF, NULL, HFILL }},
{ &hf_ieee8021ah_c_daddr, {
"C-Destination", "ieee8021ah.cdst", FT_ETHER, BASE_NONE,
NULL, 0x0, "Customer Destination Address", HFILL }},
{ &hf_ieee8021ah_c_saddr, {
"C-Source", "ieee8021ah.csrc", FT_ETHER, BASE_NONE,
NULL, 0x0, "Customer Source Address", HFILL }},
{ &hf_ieee8021ah_etype, {
"Type", "ieee8021ah.etype", FT_UINT16, BASE_HEX,
VALS(etype_vals), 0x0, NULL, HFILL }},
{ &hf_ieee8021ah_len, {
"Length", "ieee8021ah.len", FT_UINT16, BASE_DEC,
NULL, 0x0, NULL, HFILL }},
{ &hf_ieee8021ah_trailer, {
"Trailer", "ieee8021ah.trailer", FT_BYTES, BASE_NONE,
NULL, 0x0, "802.1ah Trailer", HFILL }}
};
static hf_register_info hf_1ad[] = {
{ &hf_ieee8021ad_priority, {
"Priority", "ieee8021ad.priority", FT_UINT16, BASE_DEC,
0, 0xE000, NULL, HFILL }},
{ &hf_ieee8021ad_cfi, {
"DEI", "ieee8021ad.dei", FT_UINT16, BASE_DEC,
0, 0x1000, "Drop Eligibility", HFILL }},
{ &hf_ieee8021ad_id, {
"ID", "ieee8021ad.id", FT_UINT16, BASE_DEC,
0, 0x0FFF, "Vlan ID", HFILL }},
{ &hf_ieee8021ad_svid, {
"ID", "ieee8021ad.svid", FT_UINT16, BASE_DEC,
0, 0x0FFF, "S-Vlan ID", HFILL }},
{ &hf_ieee8021ad_cvid, {
"ID", "ieee8021ad.cvid", FT_UINT16, BASE_DEC,
0, 0x0FFF, "C-Vlan ID", HFILL }},
};
static gint *ett[] = {
&ett_ieee8021ah,
&ett_ieee8021ad
};
module_t *ieee8021ah_module;
/* registration */
/* dot1ah */
proto_ieee8021ah = proto_register_protocol("IEEE 802.1ah", "IEEE 802.1AH",
"ieee8021ah");
proto_register_field_array(proto_ieee8021ah, hf, array_length(hf));
proto_ieee8021ad = proto_register_protocol("IEEE 802.1ad", "IEEE 802.1AD",
"ieee8021ad");
proto_register_field_array(proto_ieee8021ad, hf_1ad, array_length(hf_1ad));
/* register subtree array for both */
proto_register_subtree_array(ett, array_length(ett));
/* add a user preference to set the 802.1ah ethertype */
ieee8021ah_module = prefs_register_protocol(proto_ieee8021ah,
proto_reg_handoff_ieee8021ah);
prefs_register_uint_preference(ieee8021ah_module, "8021ah_ethertype",
"802.1ah Ethertype (in hex)",
"(Hexadecimal) Ethertype used to indicate IEEE 802.1ah tag.",
16, &ieee8021ah_ethertype);
}
void
proto_reg_handoff_ieee8021ah(void)
{
static gboolean prefs_initialized = FALSE;
static dissector_handle_t ieee8021ah_handle;
static unsigned int old_ieee8021ah_ethertype;
if (!prefs_initialized){
dissector_handle_t ieee8021ad_handle;
ieee8021ah_handle = create_dissector_handle(dissect_ieee8021ah,
proto_ieee8021ah);
ieee8021ad_handle = create_dissector_handle(dissect_ieee8021ad,
proto_ieee8021ad);
dissector_add_uint("ethertype", ETHERTYPE_IEEE_802_1AD, ieee8021ad_handle);
prefs_initialized = TRUE;
}
else {
dissector_delete_uint("ethertype", old_ieee8021ah_ethertype, ieee8021ah_handle);
}
old_ieee8021ah_ethertype = ieee8021ah_ethertype;
dissector_add_uint("ethertype", ieee8021ah_ethertype, ieee8021ah_handle);
}