osmocom/wireshark
14
0
Fork 1
Code Issues Pull requests Projects Releases Wiki Activity
wireshark/epan/dissectors/packet-mpls.c
Michael Mann 9b7fb8a811 Create the ability to have packet scoped "proto" data. Bug 9470 (https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=9470) 
I'm not sold on the name or module the proto_data functions live in, but I believe the function arguments are solid and gives us the most flexibility for the future.  And search/replace of a function name is easy enough to do.

The big driving force for getting this in sooner rather than later is the saved memory on ethernet packets (and IP packets soon), that used to have file_scope() proto data when all it needed was packet_scope() data (technically packet_info->pool scoped), strictly for Decode As.

All dissectors that use p_add_proto_data() only for Decode As functionality have been converted to using packet_scope().  All other dissectors were converted to using file_scope() which was the original scope for "proto" data.

svn path=/trunk/; revision=53520
2013-11-23 02:20:13 +00:00

876 lines
32 KiB
C
Raw Blame History

/* packet-mpls.c
* Routines for MPLS data packet disassembly
* RFC 3032
*
* (c) Copyright Ashok Narayanan <ashokn@cisco.com>
*
* (c) Copyright 2006, _FF_ Francesco Fondelli <francesco.fondelli@gmail.com>
* - added MPLS OAM support, ITU-T Y.1711
* - PW Associated Channel Header dissection as per RFC 4385
* - PW MPLS Control Word dissection as per RFC 4385
* - mpls subdissector table indexed by label value
* - enhanced "what's past last mpls label?" heuristic
*
* (c) Copyright 2011, Shobhank Sharma <ssharma5@ncsu.edu>
* - Removed some mpls preferences which are no longer relevant/needed like
* decode PWAC payloads as PPP traffic and assume all channel types except
* 0x21 are raw BFD.
* - MPLS extension from PW-ACH to MPLS Generic Associated Channel as per RFC 5586
* - Updated Pseudowire Associated Channel Types as per http://www.iana.org/assignments/pwe3-parameters
*
* (c) Copyright 2011, Jaihari Kalijanakiraman <jaiharik@ipinfusion.com>
* Krishnamurthy Mayya <krishnamurthy.mayya@ipinfusion.com>
* Nikitha Malgi <malgi.nikitha@ipinfusion.com>
* - Identification of BFD CC, BFD CV and ON-Demand CV ACH types as per RFC 6428, RFC 6426
* respectively and the corresponding decoding of messages
* - Decoding support for MPLS-TP Lock Instruct as per RFC 6435
* - Decoding support for MPLS-TP Fault-Management as per RFC 6427
*
* (c) Copyright 2012, Aditya Ambadkar and Diana Chris <arambadk,dvchris@ncsu.edu>
* - Added preference to select BOS label as flowlabel as per RFC 6391
*
* $Id$
*
* 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 <epan/packet.h>
#include <epan/ppptypes.h>
#include <epan/etypes.h>
#include <epan/prefs.h>
#include <epan/ipproto.h>
#include <epan/addr_resolv.h>
#include <epan/decode_as.h>
#include "packet-ppp.h"
#include "packet-mpls.h"
#include "packet-pw-common.h"
#include "packet-bfd.h"
/* As per RFC 6428 http://tools.ietf.org/html/rfc6428, Section: 3.3 */
#define ACH_TYPE_BFD_CC 0x0022
#define ACH_TYPE_BFD_CV 0x0023
/* As RFC 6426:http://tools.ietf.org/html/rfc6426, Section: 7.4 */
#define ACH_TYPE_ONDEMAND_CV 0x0025
static gint proto_mpls = -1;
static gint proto_pw_ach = -1;
static gint proto_pw_mcw = -1;
static gint ett_mpls = -1;
static gint ett_mpls_pw_ach = -1;
static gint ett_mpls_pw_mcw = -1;
static char PW_ACH[50] = "PW Associated Channel Header";
const value_string special_labels[] = {
{MPLS_LABEL_IP4_EXPLICIT_NULL, "IPv4 Explicit-Null"},
{MPLS_LABEL_ROUTER_ALERT, "Router Alert"},
{MPLS_LABEL_IP6_EXPLICIT_NULL, "IPv6 Explicit-Null"},
{MPLS_LABEL_IMPLICIT_NULL, "Implicit-Null"},
{MPLS_LABEL_OAM_ALERT, "OAM Alert"},
{MPLS_LABEL_GACH, "Generic Associated Channel Label (GAL)"},
{0, NULL }
};
static dissector_handle_t dissector_data;
static dissector_handle_t dissector_ipv6;
static dissector_handle_t dissector_ip;
static dissector_handle_t dissector_bfd;
static dissector_handle_t dissector_mpls_pm_dlm;
static dissector_handle_t dissector_mpls_pm_ilm;
static dissector_handle_t dissector_mpls_pm_dm;
static dissector_handle_t dissector_mpls_pm_dlm_dm;
static dissector_handle_t dissector_mpls_pm_ilm_dm;
static dissector_handle_t dissector_mpls_psc;
static dissector_handle_t dissector_mplstp_lock;
static dissector_handle_t dissector_mplstp_fm;
static dissector_handle_t dissector_pw_oam;
static dissector_handle_t dissector_pw_eth_heuristic;
static dissector_handle_t dissector_pw_fr;
static dissector_handle_t dissector_pw_hdlc_nocw_fr;
static dissector_handle_t dissector_pw_hdlc_nocw_hdlc_ppp;
static dissector_handle_t dissector_pw_eth_cw;
static dissector_handle_t dissector_pw_eth_nocw;
static dissector_handle_t dissector_pw_satop;
static dissector_handle_t dissector_itdm;
static dissector_handle_t dissector_mpls_pw_atm_n1_cw;
static dissector_handle_t dissector_mpls_pw_atm_n1_nocw;
static dissector_handle_t dissector_mpls_pw_atm_11_aal5pdu;
static dissector_handle_t dissector_mpls_pw_atm_aal5_sdu;
static dissector_handle_t dissector_pw_cesopsn;
enum mpls_default_dissector_t {
MDD_PW_ETH_HEUR = 0
,MDD_PW_SATOP
,MDD_PW_CESOPSN
,MDD_MPLS_PW_FR_DLCI
,MDD_MPLS_PW_HDLC_NOCW_FRPORT
,MDD_MPLS_PW_HDLC_NOCW_HDLC_PPP
,MDD_MPLS_PW_ETH_CW
,MDD_MPLS_PW_ETH_NOCW
,MDD_MPLS_PW_GENERIC
,MDD_ITDM
,MDD_MPLS_PW_ATM_N1_CW
,MDD_MPLS_PW_ATM_N1_NOCW
,MDD_MPLS_PW_ATM_11_OR_AAL5_PDU
,MDD_MPLS_PW_ATM_AAL5_SDU
};
/* TODO the content of mpls_default_payload menu
* should be automatically built like mpls "decode as..." menu;
* this way, mpls_default_payload will be automatically filled up when
* new mpls-specific dissector added.
*/
static const enum_val_t mpls_default_payload_defs[] = {
{
"pw satop"
,pwc_longname_pw_satop
,MDD_PW_SATOP
},
{
"pw cesopsn"
,pwc_longname_pw_cesopsn
,MDD_PW_CESOPSN
},
{
"mpls pw ethernet heuristic"
,"Ethernet MPLS PW (CW is heuristically detected)"
,MDD_PW_ETH_HEUR
},
{
"mpls pw fr dlci"
,"Frame relay DLCI MPLS PW"
,MDD_MPLS_PW_FR_DLCI
},
{
"mpls pw hdlc no_cw fr_port"
,"HDLC MPLS PW (no CW), FR Port mode"
,MDD_MPLS_PW_HDLC_NOCW_FRPORT
},
{
"mpls pw hdlc no_cw hdlc payload_ppp"
,"HDLC MPLS PW (no CW), HDLC mode, PPP payload"
,MDD_MPLS_PW_HDLC_NOCW_HDLC_PPP
},
{
"mpls pw ethernet cw"
,"Ethernet MPLS PW (with CW)"
,MDD_MPLS_PW_ETH_CW
},
{
"mpls pw ethernet no_cw"
,"Ethernet MPLS PW (no CW, early implementations)"
,MDD_MPLS_PW_ETH_NOCW
},
{
"mpls pw generic cw"
,"Generic MPLS PW (with Generic/Preferred MPLS CW)"
,MDD_MPLS_PW_GENERIC
},
{
"itdm"
,"Internal TDM"
,MDD_ITDM
},
{
"mpls pw atm n_to_one cw"
,pwc_longname_pw_atm_n1_cw
,MDD_MPLS_PW_ATM_N1_CW
},
{
"mpls pw atm n_to_one no_cw"
,pwc_longname_pw_atm_n1_nocw
,MDD_MPLS_PW_ATM_N1_NOCW
},
{
"mpls pw atm one_to_one or aal5_pdu"
,pwc_longname_pw_atm_11_or_aal5_pdu
,MDD_MPLS_PW_ATM_11_OR_AAL5_PDU
},
{
"mpls pw atm aal5_sdu"
,pwc_longname_pw_atm_aal5_sdu
,MDD_MPLS_PW_ATM_AAL5_SDU
},
{
NULL
,NULL
,-1
}
};
/* For RFC6391 - Flow aware transport of pseudowire over a mpls PSN*/
static gboolean mpls_bos_flowlabel = FALSE;
static int hf_mpls_label = -1;
static int hf_mpls_label_special = -1;
static int hf_mpls_exp = -1;
static int hf_mpls_bos = -1;
static int hf_mpls_ttl = -1;
static gint mpls_default_payload = 0;
static int hf_mpls_pw_ach_ver = -1;
static int hf_mpls_pw_ach_res = -1;
static int hf_mpls_pw_ach_channel_type = -1;
static int hf_mpls_pw_mcw_flags = -1;
static int hf_mpls_pw_mcw_length = -1;
static int hf_mpls_pw_mcw_sequence_number = -1;
#if 0 /*not used yet*/
/*
* MPLS PW types
* http://www.iana.org/assignments/pwe3-parameters
*/
static const value_string mpls_pw_types[] = {
{ 0x0001, "Frame Relay DLCI ( Martini Mode )" },
{ 0x0002, "ATM AAL5 SDU VCC transport" },
{ 0x0003, "ATM transparent cell transport" },
{ 0x0004, "Ethernet Tagged Mode" },
{ 0x0005, "Ethernet" },
{ 0x0006, "HDLC" },
{ 0x0007, "PPP" },
{ 0x0008, "SONET/SDH Circuit Emulation Service Over MPLS" },
{ 0x0009, "ATM n-to-one VCC cell transport" },
{ 0x000A, "ATM n-to-one VPC cell transport" },
{ 0x000B, "IP Layer2 Transport" },
{ 0x000C, "ATM one-to-one VCC Cell Mode" },
{ 0x000D, "ATM one-to-one VPC Cell Mode" },
{ 0x000E, "ATM AAL5 PDU VCC transport" },
{ 0x000F, "Frame-Relay Port mode" },
{ 0x0010, "SONET/SDH Circuit Emulation over Packet" },
{ 0x0011, "Structure-agnostic E1 over Packet" },
{ 0x0012, "Structure-agnostic T1 (DS1) over Packet" },
{ 0x0013, "Structure-agnostic E3 over Packet" },
{ 0x0014, "Structure-agnostic T3 (DS3) over Packet" },
{ 0x0015, "CESoPSN basic mode" },
{ 0x0016, "TDMoIP AAL1 Mode" },
{ 0x0017, "CESoPSN TDM with CAS" },
{ 0x0018, "TDMoIP AAL2 Mode" },
{ 0x0019, "Frame Relay DLCI" },
{ 0x001A, "ROHC Transport Header-compressed Packets" },/*[RFC4995][RFC4901]*/
{ 0x001B, "ECRTP Transport Header-compressed Packets" },/*[RFC3545][RFC4901]*/
{ 0x001C, "IPHC Transport Header-compressed Packets" },/*[RFC2507][RFC4901]*/
{ 0x001D, "cRTP Transport Header-compressed Packets" },/*[RFC2508][RFC4901]*/
{ 0x001E, "ATM VP Virtual Trunk" },/*[MFA9]*/
{ 0x001F, "Reserved" },/*[Bryant] 2008-04-17*/
{ 0, NULL }
};
static value_string_ext mpls_pw_types_ext = VALUE_STRING_EXT_INIT(mpls_pw_types);
#endif
/*
* MPLS PW Associated Channel Types
* as per http://www.iana.org/assignments/pwe3-parameters
* and http://tools.ietf.org/html/draft-ietf-pwe3-vccv-bfd-05 clause 3.2
*/
static const value_string mpls_pwac_types[] = {
{ 0x0000, "Reserved"},
{ 0x0001, "Management Communication Channel (MCC)"},
{ 0x0002, "Signaling Communication Channel (SCC)"},
{ 0x0007, "BFD Control, PW-ACH-encapsulated (BFD Without IP/UDP Headers)" },
{ 0x000A, "MPLS Direct Loss Measurement (DLM)"},
{ 0x000B, "MPLS Inferred Loss Measurement (ILM)"},
{ 0x000C, "MPLS Delay Measurement (DM)"},
{ 0x000D, "MPLS Direct Loss and Delay Measurement (DLM+DM)"},
{ 0x000E, "MPLS Inferred Loss and Delay Measurement (ILM+DM)"},
{ 0x0021, "IPv4 packet" },
{ 0x0022, "MPLS-TP CC message"},
{ 0x0023, "MPLS-TP CV message"},
{ 0x0024, "Protection State Coordination Protocol (PSC)"},
{ 0x0025, "On-Demand CV"},
{ 0x0026, "LI"},
{ 0x0027, "Pseudo-Wire OAM"},
{ 0x0057, "IPv6 packet" },
{ 0x0058, "Fault OAM"},
{ 0x7FF8, "Reserved for Experimental Use"},
{ 0x7FF9, "Reserved for Experimental Use"},
{ 0x7FFA, "Reserved for Experimental Use"},
{ 0x7FFB, "Reserved for Experimental Use"},
{ 0x7FFC, "Reserved for Experimental Use"},
{ 0x7FFD, "Reserved for Experimental Use"},
{ 0x7FFE, "Reserved for Experimental Use"},
{ 0x7FFF, "Reserved for Experimental Use"},
{ 0, NULL }
};
static value_string_ext mpls_pwac_types_ext = VALUE_STRING_EXT_INIT(mpls_pwac_types);
static dissector_table_t mpls_subdissector_table;
static void mpls_prompt(packet_info *pinfo, gchar* result)
{
g_snprintf(result, MAX_DECODE_AS_PROMPT_LEN, "Data after label %u as",
GPOINTER_TO_UINT(p_get_proto_data(pinfo->pool, pinfo, proto_mpls, 0)));
}
static gpointer mpls_value(packet_info *pinfo)
{
return p_get_proto_data(pinfo->pool, pinfo, proto_mpls, 0);
}
/*
* Given a 4-byte MPLS label starting at offset "offset", in tvbuff "tvb",
* decode it.
* Return the label in "label", EXP bits in "exp",
* bottom_of_stack in "bos", and TTL in "ttl"
*/
void
decode_mpls_label(tvbuff_t *tvb, int offset,
guint32 *label, guint8 *exp,
guint8 *bos, guint8 *ttl)
{
guint8 octet0 = tvb_get_guint8(tvb, offset+0);
guint8 octet1 = tvb_get_guint8(tvb, offset+1);
guint8 octet2 = tvb_get_guint8(tvb, offset+2);
*label = (octet0 << 12) + (octet1 << 4) + ((octet2 >> 4) & 0xff);
*exp = (octet2 >> 1) & 0x7;
*bos = (octet2 & 0x1);
*ttl = tvb_get_guint8(tvb, offset+3);
}
/*
* FF: PW Associated Channel Header dissection as per RFC 4385.
*/
static void
dissect_pw_ach(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
tvbuff_t *next_tvb;
guint16 channel_type;
if (tvb_reported_length_remaining(tvb, 0) < 4) {
proto_tree_add_text(tree, tvb, 0, -1, "Error processing Message");
return;
}
channel_type = tvb_get_ntohs(tvb, 2);
if (tree) {
proto_tree *mpls_pw_ach_tree;
proto_item *ti;
guint16 res;
ti = proto_tree_add_item(tree, proto_pw_ach, tvb, 0, 4, ENC_NA);
mpls_pw_ach_tree = proto_item_add_subtree(ti, ett_mpls_pw_ach);
proto_tree_add_item(mpls_pw_ach_tree, hf_mpls_pw_ach_ver,
tvb, 0, 1, ENC_BIG_ENDIAN);
res = tvb_get_guint8(tvb, 1);
ti = proto_tree_add_uint(mpls_pw_ach_tree, hf_mpls_pw_ach_res,
tvb, 1, 1, res);
if (res != 0)
proto_tree_add_text(mpls_pw_ach_tree, tvb, 1, 1,
"Error: this byte is reserved and must be 0");
else
PROTO_ITEM_SET_HIDDEN(ti);
proto_tree_add_uint_format_value(mpls_pw_ach_tree, hf_mpls_pw_ach_channel_type,
tvb, 2, 2, channel_type,
"%s (0x%04x)",
val_to_str_ext_const(channel_type, &mpls_pwac_types_ext, "Unknown"),
channel_type);
} /* if (tree) */
next_tvb = tvb_new_subset_remaining(tvb, 4);
switch (channel_type) {
case ACH_TYPE_BFD_CC:
call_dissector(dissector_bfd, next_tvb, pinfo, tree); /* bfd_control() */
break;
case ACH_TYPE_BFD_CV:
call_dissector(dissector_bfd, next_tvb, pinfo, tree); /* bfd_control() */
dissect_bfd_mep(next_tvb, tree, 0);
break;
case ACH_TYPE_ONDEMAND_CV:
dissect_mpls_echo(next_tvb, pinfo, tree, NULL);
break;
case 0x21: /* IPv4, RFC4385 clause 6. */
call_dissector(dissector_ip, next_tvb, pinfo, tree);
break;
case 0x7: /* PWACH-encapsulated BFD, RFC 5885 */
call_dissector(dissector_bfd, next_tvb, pinfo, tree);
break;
case 0x57: /* IPv6, RFC4385 clause 6. */
call_dissector(dissector_ipv6, next_tvb, pinfo, tree);
break;
case 0x000A: /* FF: MPLS PM, RFC 6374, DLM */
call_dissector(dissector_mpls_pm_dlm, next_tvb, pinfo, tree);
break;
case 0x000B: /* FF: MPLS PM, RFC 6374, ILM */
call_dissector(dissector_mpls_pm_ilm, next_tvb, pinfo, tree);
break;
case 0x000C: /* FF: MPLS PM, RFC 6374, DM */
call_dissector(dissector_mpls_pm_dm, next_tvb, pinfo, tree);
break;
case 0x000D: /* FF: MPLS PM, RFC 6374, DLM+DM */
call_dissector(dissector_mpls_pm_dlm_dm, next_tvb, pinfo, tree);
break;
case 0x000E: /* FF: MPLS PM, RFC 6374, ILM+DM */
call_dissector(dissector_mpls_pm_ilm_dm, next_tvb, pinfo, tree);
break;
case 0x0024: /* FF: PSC, RFC 6378 */
call_dissector(dissector_mpls_psc, next_tvb, pinfo, tree);
break;
case 0x0026: /* KM: MPLSTP LOCK, RFC 6435 */
call_dissector(dissector_mplstp_lock, next_tvb, pinfo, tree);
break;
case 0x0027: /* KM: MPLSTP PW-OAM, RFC 6478 */
call_dissector(dissector_pw_oam, next_tvb, pinfo, tree);
break;
case 0x0058: /* KM: MPLSTP FM, RFC 6427 */
call_dissector(dissector_mplstp_fm, next_tvb, pinfo, tree);
break;
default:
call_dissector(dissector_data, next_tvb, pinfo, tree);
break;
}
}
gboolean
dissect_try_cw_first_nibble( tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree )
{
guint8 nibble;
nibble = (tvb_get_guint8(tvb, 0 ) >> 4) & 0x0F;
switch ( nibble )
{
case 6:
call_dissector(dissector_ipv6, tvb, pinfo, tree);
return TRUE;
case 4:
call_dissector(dissector_ip, tvb, pinfo, tree);
return TRUE;
case 1:
dissect_pw_ach(tvb, pinfo, tree );
return TRUE;
default:
break;
}
return FALSE;
}
/*
* FF: Generic/Preferred PW MPLS Control Word dissection as per RFC 4385.
*/
static void
dissect_pw_mcw(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
tvbuff_t *next_tvb;
if (tvb_reported_length_remaining(tvb, 0) < 4) {
proto_tree_add_text(tree, tvb, 0, -1, "Error processing Message");
return;
}
if ( dissect_try_cw_first_nibble( tvb, pinfo, tree ))
return;
if (tree) {
proto_tree *mpls_pw_mcw_tree;
proto_item *ti;
ti = proto_tree_add_item(tree, proto_pw_mcw, tvb, 0, 4, ENC_NA);
mpls_pw_mcw_tree = proto_item_add_subtree(ti, ett_mpls_pw_mcw);
proto_tree_add_item(mpls_pw_mcw_tree, hf_mpls_pw_mcw_flags,
tvb, 0, 2, ENC_BIG_ENDIAN);
/* bits 4 to 7 and FRG bits are displayed together */
proto_tree_add_item(mpls_pw_mcw_tree, hf_mpls_pw_mcw_length,
tvb, 1, 1, ENC_BIG_ENDIAN);
proto_tree_add_item(mpls_pw_mcw_tree, hf_mpls_pw_mcw_sequence_number,
tvb, 2, 2, ENC_BIG_ENDIAN);
}
next_tvb = tvb_new_subset_remaining(tvb, 4);
call_dissector(dissector_data, next_tvb, pinfo, tree);
}
static void
dissect_mpls(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
int offset = 0;
guint32 label = MPLS_LABEL_INVALID;
guint8 exp;
guint8 bos;
guint8 ttl;
tvbuff_t *next_tvb;
gboolean found;
guint8 first_nibble;
struct mplsinfo mplsinfo;
col_set_str(pinfo->cinfo, COL_PROTOCOL, "MPLS");
col_set_str(pinfo->cinfo, COL_INFO, "MPLS Label Switched Packet");
/* Ensure structure is initialized */
memset(&mplsinfo, 0, sizeof(struct mplsinfo));
/* Start Decoding Here. */
while (tvb_reported_length_remaining(tvb, offset) > 0) {
decode_mpls_label(tvb, offset, &label, &exp, &bos, &ttl);
/*
* FF: export (last shim in stack) info to subdissectors and
* update pinfo
*/
mplsinfo.label = label;
p_add_proto_data(pinfo->pool, pinfo, proto_mpls, 0, GUINT_TO_POINTER(label));
mplsinfo.exp = exp;
mplsinfo.bos = bos;
mplsinfo.ttl = ttl;
if (tree) {
proto_item *ti;
proto_tree *mpls_tree;
ti = proto_tree_add_item(tree, proto_mpls, tvb, offset, 4, ENC_NA);
mpls_tree = proto_item_add_subtree(ti, ett_mpls);
if (mpls_bos_flowlabel) {
proto_item_append_text(ti, ", Label: %u (Flow Label)", label);
} else {
proto_item_append_text(ti, ", Label: %u", label);
}
if (label <= MPLS_LABEL_MAX_RESERVED){
proto_tree_add_item(mpls_tree, hf_mpls_label_special, tvb,
offset, 4, ENC_BIG_ENDIAN);
proto_item_append_text(ti, " (%s)",
val_to_str_const(label, special_labels, "Reserved - Unknown"));
} else {
proto_tree_add_item(mpls_tree, hf_mpls_label, tvb, offset, 4,
ENC_BIG_ENDIAN);
}
proto_tree_add_item(mpls_tree, hf_mpls_exp, tvb, offset, 4,
ENC_BIG_ENDIAN);
proto_item_append_text(ti, ", Exp: %u", exp);
proto_tree_add_item(mpls_tree, hf_mpls_bos , tvb, offset, 4,
ENC_BIG_ENDIAN);
proto_item_append_text(ti, ", S: %u", bos);
proto_tree_add_item(mpls_tree, hf_mpls_ttl, tvb, offset, 4,
ENC_BIG_ENDIAN);
proto_item_append_text(ti, ", TTL: %u", ttl);
}
offset += 4;
if ((label == MPLS_LABEL_GACH) && !bos) {
proto_tree_add_text(tree, tvb, 0, -1, "Invalid Label");
}
if ((label == MPLS_LABEL_GACH) && bos) {
g_strlcpy(PW_ACH, "Generic Associated Channel Header",50);
next_tvb = tvb_new_subset_remaining(tvb, offset);
dissect_pw_ach( next_tvb, pinfo, tree );
return;
}
else
g_strlcpy(PW_ACH, "PW Associated Channel Header",50);
if (bos)
break;
}
first_nibble = (tvb_get_guint8(tvb, offset) >> 4) & 0x0F;
next_tvb = tvb_new_subset_remaining(tvb, offset);
/* 1) explicit label-to-dissector binding ? */
found = dissector_try_uint_new(mpls_subdissector_table, label,
next_tvb, pinfo, tree, FALSE, &mplsinfo);
if (found)
return;
/* 2) use the 1st nibble logic (see BCP 4928, RFC 4385 and 5586) */
if (first_nibble == 4) {
call_dissector(dissector_ip, next_tvb, pinfo, tree);
/* IP dissector may reduce the length of the tvb.
We need to do the same, so that ethernet trailer is detected. */
set_actual_length(tvb, offset+tvb_reported_length(next_tvb));
return;
} else if (first_nibble == 6) {
call_dissector(dissector_ipv6, next_tvb, pinfo, tree);
/* IPv6 dissector may reduce the length of the tvb.
We need to do the same, so that ethernet trailer is detected. */
set_actual_length(tvb, offset+tvb_reported_length(next_tvb));
return;
} else if (first_nibble == 1) {
dissect_pw_ach(next_tvb, pinfo, tree);
return;
} else if (first_nibble == 0) {
/*
* FF: it should be a PW with a CW but... it's not
* guaranteed (e.g. an Ethernet PW w/o CW and a DA MAC
* address like 00:xx:xx:xx:xx:xx). So, let the user and
* eventually any further PW heuristics decide.
*/
}
/* 3) use the mpls_default_payload info from user */
switch (mpls_default_payload) {
case MDD_PW_SATOP:
call_dissector(dissector_pw_satop, next_tvb, pinfo, tree);
break;
case MDD_PW_CESOPSN:
call_dissector(dissector_pw_cesopsn, next_tvb, pinfo, tree);
break;
case MDD_PW_ETH_HEUR:
call_dissector(dissector_pw_eth_heuristic, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_FR_DLCI:
call_dissector(dissector_pw_fr, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_HDLC_NOCW_FRPORT:
call_dissector(dissector_pw_hdlc_nocw_fr, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_HDLC_NOCW_HDLC_PPP:
call_dissector(dissector_pw_hdlc_nocw_hdlc_ppp,next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_ETH_CW:
call_dissector(dissector_pw_eth_cw, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_ETH_NOCW:
call_dissector(dissector_pw_eth_nocw, next_tvb, pinfo, tree);
break;
case MDD_ITDM:
call_dissector(dissector_itdm, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_ATM_N1_CW:
call_dissector(dissector_mpls_pw_atm_n1_cw, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_ATM_N1_NOCW:
call_dissector(dissector_mpls_pw_atm_n1_nocw, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_ATM_11_OR_AAL5_PDU:
call_dissector(dissector_mpls_pw_atm_11_aal5pdu, next_tvb, pinfo, tree);
break;
case MDD_MPLS_PW_ATM_AAL5_SDU:
call_dissector(dissector_mpls_pw_atm_aal5_sdu, next_tvb, pinfo, tree);
break;
default: /* fallthrough */
case MDD_MPLS_PW_GENERIC:
dissect_pw_mcw(next_tvb, pinfo, tree);
break;
}
}
void
proto_register_mpls(void)
{
static hf_register_info mplsf_info[] = {
/* MPLS header fields */
{&hf_mpls_label,
{"MPLS Label", "mpls.label",
FT_UINT32, BASE_DEC, NULL, 0xFFFFF000,
NULL, HFILL }
},
{&hf_mpls_label_special,
{"MPLS Label", "mpls.label",
FT_UINT32, BASE_DEC, VALS(special_labels), 0xFFFFF000,
NULL, HFILL }
},
{&hf_mpls_exp,
{"MPLS Experimental Bits", "mpls.exp",
FT_UINT32, BASE_DEC, NULL, 0x00000E00,
NULL, HFILL }
},
{&hf_mpls_bos,
{"MPLS Bottom Of Label Stack", "mpls.bottom",
FT_UINT32, BASE_DEC, NULL, 0x00000100,
NULL, HFILL }
},
{&hf_mpls_ttl,
{"MPLS TTL", "mpls.ttl",
FT_UINT32, BASE_DEC, NULL, 0x0000000FF,
NULL, HFILL }
},
/* PW Associated Channel Header fields */
{&hf_mpls_pw_ach_ver,
{"Channel Version", "pwach.ver",
FT_UINT8, BASE_DEC, NULL, 0x0F,
"PW Associated Channel Version", HFILL }
},
{&hf_mpls_pw_ach_res,
{"Reserved", "pwach.res",
FT_UINT8, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
{&hf_mpls_pw_ach_channel_type,
{"Channel Type", "pwach.channel_type",
FT_UINT16, BASE_HEX, NULL, 0x0,
"PW Associated Channel Type", HFILL }
},
/* Generic/Preferred PW MPLS Control Word fields */
{&hf_mpls_pw_mcw_flags,
{"Flags", "pwmcw.flags",
FT_UINT8, BASE_HEX, NULL, 0x0FC0,
"Generic/Preferred PW MPLS Control Word Flags", HFILL }
},
{&hf_mpls_pw_mcw_length,
{"Length", "pwmcw.length",
FT_UINT8, BASE_DEC, NULL, 0x3F,
"Generic/Preferred PW MPLS Control Word Length", HFILL }
},
{&hf_mpls_pw_mcw_sequence_number,
{"Sequence Number", "pwmcw.sequence_number",
FT_UINT16, BASE_DEC, NULL, 0x0,
"Generic/Preferred PW MPLS Control Word Sequence Number", HFILL }
},
};
static gint *ett[] = {
&ett_mpls,
&ett_mpls_pw_ach,
&ett_mpls_pw_mcw,
};
/* Decode As handling */
static build_valid_func mpls_da_build_value[1] = {mpls_value};
static decode_as_value_t mpls_da_values = {mpls_prompt, 1, mpls_da_build_value};
static decode_as_t mpls_da = {"mpls", "MPLS", "mpls.label", 1, 0, &mpls_da_values, NULL, NULL,
decode_as_default_populate_list, decode_as_default_reset, decode_as_default_change, NULL};
module_t * module_mpls;
/* FF: mpls subdissector table is indexed by label */
mpls_subdissector_table = register_dissector_table("mpls.label",
"MPLS protocol",
FT_UINT32, BASE_DEC);
proto_mpls = proto_register_protocol("MultiProtocol Label Switching Header",
"MPLS", "mpls");
proto_pw_ach = proto_register_protocol(PW_ACH,
"PW Associated Channel", "pwach");
proto_pw_mcw = proto_register_protocol("PW MPLS Control Word (generic/preferred)",
"Generic PW (with CW)", "pwmcw");
proto_register_field_array(proto_mpls, mplsf_info, array_length(mplsf_info));
proto_register_subtree_array(ett, array_length(ett));
register_dissector("mpls", dissect_mpls, proto_mpls);
register_dissector("mplspwcw", dissect_pw_mcw, proto_pw_mcw );
module_mpls = prefs_register_protocol( proto_mpls, NULL );
prefs_register_enum_preference(module_mpls,
"mplspref.payload",
"Default decoder for MPLS payload",
"Default decoder for MPLS payload",
&mpls_default_payload,
mpls_default_payload_defs,
FALSE );
/* RFC6391: Flow aware transport of pseudowire*/
prefs_register_bool_preference(module_mpls,
"flowlabel_in_mpls_header",
"Assume bottom of stack label as Flow label",
"Lowest label is used to segregate flows inside a pseudowire",
&mpls_bos_flowlabel);
register_decode_as(&mpls_da);
}
void
proto_reg_handoff_mpls(void)
{
dissector_handle_t mpls_handle;
mpls_handle = find_dissector("mpls");
dissector_add_uint("ethertype", ETHERTYPE_MPLS, mpls_handle);
dissector_add_uint("ethertype", ETHERTYPE_MPLS_MULTI, mpls_handle);
dissector_add_uint("chdlc.protocol", ETHERTYPE_MPLS, mpls_handle);
dissector_add_uint("chdlc.protocol", ETHERTYPE_MPLS_MULTI, mpls_handle);
dissector_add_uint("gre.proto", ETHERTYPE_MPLS, mpls_handle);
dissector_add_uint("gre.proto", ETHERTYPE_MPLS_MULTI, mpls_handle);
dissector_add_uint("ip.proto", IP_PROTO_MPLS_IN_IP, mpls_handle);
mpls_handle = find_dissector("mplspwcw");
dissector_add_uint( "mpls.label", MPLS_LABEL_INVALID, mpls_handle );
dissector_data = find_dissector("data");
dissector_ipv6 = find_dissector("ipv6");
dissector_ip = find_dissector("ip");
dissector_bfd = find_dissector("bfd");
dissector_mpls_pm_dlm = find_dissector("mpls_pm_dlm");
dissector_mpls_pm_ilm = find_dissector("mpls_pm_ilm");
dissector_mpls_pm_dm = find_dissector("mpls_pm_dm");
dissector_mpls_pm_dlm_dm = find_dissector("mpls_pm_dlm_dm");
dissector_mpls_pm_ilm_dm = find_dissector("mpls_pm_ilm_dm");
dissector_mpls_psc = find_dissector("mpls_psc");
dissector_mplstp_lock = find_dissector("mplstp_lock");
dissector_mplstp_fm = find_dissector("mplstp_fm");
dissector_pw_oam = find_dissector("pw_oam");
dissector_pw_eth_heuristic = find_dissector("pw_eth_heuristic");
dissector_pw_fr = find_dissector("pw_fr");
dissector_pw_hdlc_nocw_fr = find_dissector("pw_hdlc_nocw_fr");
dissector_pw_eth_cw = find_dissector("pw_eth_cw");
dissector_pw_eth_nocw = find_dissector("pw_eth_nocw");
dissector_pw_satop = find_dissector("pw_satop_mpls");
dissector_itdm = find_dissector("itdm");
dissector_mpls_pw_atm_n1_cw = find_dissector("mpls_pw_atm_n1_cw");
dissector_mpls_pw_atm_n1_nocw = find_dissector("mpls_pw_atm_n1_nocw");
dissector_mpls_pw_atm_11_aal5pdu= find_dissector("mpls_pw_atm_11_or_aal5_pdu");
dissector_mpls_pw_atm_aal5_sdu = find_dissector("mpls_pw_atm_aal5_sdu");
dissector_pw_cesopsn = find_dissector("pw_cesopsn_mpls");
}
/*
* Editor modelines
*
* Local Variables:
* c-basic-offset: 4
* tab-width: 8
* indent-tabs-mode: nil
* End:
*
* ex: set shiftwidth=4 tabstop=8 expandtab:
* :indentSize=4:tabSize=8:noTabs=true:
*/
Reference in a new issue View git blame Copy permalink