755 lines
31 KiB
C
755 lines
31 KiB
C
/* packet-msdp.c
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* Routines for Multicast Source Discovery Protocol (MSDP) dissection.
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* RFC 3618
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*
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* Copyright 2001, Heikki Vatiainen <hessu@cs.tut.fi>
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*
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* Wireshark - Network traffic analyzer
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* By Gerald Combs <gerald@wireshark.org>
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* Copyright 1998 Gerald Combs
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*
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* SPDX-License-Identifier: GPL-2.0-or-later
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*/
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#include "config.h"
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#include <epan/packet.h>
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#include <epan/to_str.h>
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#include <epan/expert.h>
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void proto_register_msdp(void);
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void proto_reg_handoff_msdp(void);
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/* MSDP (Type-Length-Value) TLV types. The messages are a sequence of TLVs. */
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enum { MSDP_SA = 1,
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MSDP_SA_REQ,
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MSDP_SA_RSP,
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MSDP_KEEP_ALIVE,
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MSDP_NOTIFICATION, /* draft 10, but not RFC 3618 */
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/* These are only assigned in MSDP spec. Their use is specified
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* elsewhere */
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MSDP_TRACE_IN_PROGRESS,
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MSDP_TRACE_REPLY
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};
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static const value_string msdp_types[] = {
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{ MSDP_SA, "IPv4 Source-Active" },
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{ MSDP_SA_REQ, "IPv4 Source-Active Request" },
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{ MSDP_SA_RSP, "IPv4 Source-Active Response" },
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{ MSDP_KEEP_ALIVE, "KeepAlive" },
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{ MSDP_NOTIFICATION, "Notification" },
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{ MSDP_TRACE_IN_PROGRESS, "MSDP traceroute in progress" },
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{ MSDP_TRACE_REPLY, "MSDP traceroute reply" },
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{ 0, NULL },
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};
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/* Error codes */
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enum { MESSAGE_HEADER_ERROR = 1,
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SA_REQUEST_ERROR,
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SA_MESSAGE_SA_RESPONSE_ERROR,
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HOLD_TIMER_EXPIRED,
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FSM_ERROR,
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NOTIFICATION,
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CEASE
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};
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static const value_string error_vals[] = {
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{ MESSAGE_HEADER_ERROR, "Message Header Error" },
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{ SA_REQUEST_ERROR, "SA-Request Error" },
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{ SA_MESSAGE_SA_RESPONSE_ERROR, "SA-Message/SA-Response Error" },
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{ HOLD_TIMER_EXPIRED, "Hold Timer Expired" },
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{ FSM_ERROR, "Finite State Machine Error" },
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{ NOTIFICATION, "Notification" },
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{ CEASE, "Cease" },
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{ 0, NULL },
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};
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/* Message Header Error subcodes */
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static const value_string hdr_error_vals[] = {
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{ 0, "Unspecific" },
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{ 2, "Bad Message Length" },
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{ 3, "Bad Message Type" },
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{ 0, NULL },
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};
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/* SA-Request Error subcodes (the O-bit is always clear) */
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static const value_string sa_req_error_vals[] = {
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{ 0, "Unspecific" },
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{ 1, "Invalid Group" },
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{ 0, NULL },
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};
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/* SA-Message/SA-Response Error subcodes */
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static const value_string sa_msg_error_vals[] = {
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{ 0, "Unspecific" },
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{ 1, "Invalid Entry Count" },
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{ 2, "Invalid RP Address" },
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{ 3, "Invalid Group Address" },
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{ 4, "Invalid Source Address" },
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{ 5, "Invalid Sprefix Length" },
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{ 6, "Looping SA (Self is RP)" },
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{ 7, "Unknown Encapsulation" },
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{ 8, "Administrative Scope Boundary Violated" },
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{ 0, NULL },
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};
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/* Finite State Machine Error subcodes (the O-bit is always clear) */
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static const value_string fsm_error_vals[] = {
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{ 0, "Unspecific" },
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{ 1, "Unexpected Message Type FSM Error" },
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{ 0, NULL },
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};
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/*
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* Hold Timer Expired subcodes (the O-bit is always clear):
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* Notification subcodes (the O-bit is always clear):
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* Cease subcodes (the O-bit is always clear):
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*
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* These have only "Unspecific" specified.
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*/
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static const value_string sa_unspec_error_vals[] = {
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{ 0, "Unspecific" },
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{ 0, NULL },
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};
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#define MSDP_PORT 639
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/* Initialize the protocol and registered fields */
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static int proto_msdp = -1;
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static int hf_msdp_type = -1;
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static int hf_msdp_length = -1;
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static int hf_msdp_sa_entry_count = -1;
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static int hf_msdp_sa_rp_addr = -1;
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static int hf_msdp_sa_reserved = -1;
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static int hf_msdp_sa_sprefix_len = -1;
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static int hf_msdp_sa_group_addr = -1;
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static int hf_msdp_sa_src_addr = -1;
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static int hf_msdp_sa_req_res = -1;
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static int hf_msdp_sa_req_group = -1;
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static int hf_msdp_not_o = -1;
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static int hf_msdp_not_error = -1;
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static int hf_msdp_not_error_sub = -1;
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static int hf_msdp_not_group_address = -1;
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static int hf_msdp_not_rp_address = -1;
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static int hf_msdp_not_source_address = -1;
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static int hf_msdp_not_res = -1;
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static int hf_msdp_not_entry_count = -1;
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static int hf_msdp_not_sprefix_len = -1;
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static int hf_msdp_tlv_contents = -1;
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static int hf_msdp_trailing_junk = -1;
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static int hf_msdp_unknown_data = -1;
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static gint ett_msdp = -1;
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static gint ett_msdp_sa_entry = -1;
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static gint ett_msdp_sa_enc_data = -1;
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static gint ett_msdp_not_data = -1;
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static expert_field ei_msdp_tlv_len_too_short = EI_INIT;
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static expert_field ei_msdp_tlv_len_too_long = EI_INIT;
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static dissector_handle_t ip_handle;
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static void
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dissect_msdp_sa(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
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int *offset, int length, proto_item *length_item);
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static void
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dissect_msdp_notification(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
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int *offset, guint16 tlv_len, proto_item *length_item);
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static int
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dissect_msdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
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{
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proto_item *ti;
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proto_tree *msdp_tree;
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proto_item *length_item;
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int offset;
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guint32 type;
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guint32 length;
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col_set_str(pinfo->cinfo, COL_PROTOCOL, "MSDP");
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col_set_str(pinfo->cinfo, COL_INFO, val_to_str_const(tvb_get_guint8(tvb, 0),
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msdp_types,
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"<Unknown MSDP TLV type>"));
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ti = proto_tree_add_item(tree, proto_msdp, tvb, 0, -1, ENC_NA);
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msdp_tree = proto_item_add_subtree(ti, ett_msdp);
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offset = 0;
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while (tvb_reported_length_remaining(tvb, offset) != 0) {
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proto_tree_add_item_ret_uint(msdp_tree, hf_msdp_type, tvb, offset, 1, ENC_BIG_ENDIAN, &type);
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length_item = proto_tree_add_item_ret_uint(msdp_tree, hf_msdp_length, tvb, offset + 1, 2, ENC_BIG_ENDIAN, &length);
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if (length < 3) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length < 3");
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break;
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}
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offset += 3;
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length -= 3;
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switch (type) {
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case MSDP_SA:
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dissect_msdp_sa(tvb, pinfo, msdp_tree, &offset,
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length, length_item);
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break;
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case MSDP_SA_REQ:
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/*
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* This type is mentioned in the RFC but the format
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* isn't described.
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*/
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if (length < 1) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for IPv4 Source-Active Request < 8");
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break;
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}
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proto_tree_add_item(msdp_tree, hf_msdp_sa_req_res, tvb, offset, 1, ENC_BIG_ENDIAN);
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offset += 1;
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length -= 1;
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if (length < 4) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for IPv4 Source-Active Request < 8");
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offset += length;
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break;
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}
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proto_tree_add_item(msdp_tree, hf_msdp_sa_req_group, tvb, offset, 4, ENC_BIG_ENDIAN);
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offset += 4;
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length -= 4;
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if (length > 0) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_long,
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"TLV length for KeepAlive > 8");
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proto_tree_add_item(tree, hf_msdp_trailing_junk, tvb, offset, length, ENC_NA);
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offset += length;
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}
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break;
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case MSDP_SA_RSP:
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/*
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* This type is mentioned in the RFC but the format
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* isn't described.
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*/
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dissect_msdp_sa(tvb, pinfo, msdp_tree, &offset,
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length, length_item);
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break;
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case MSDP_KEEP_ALIVE:
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if (length > 0) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_long,
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"TLV length for KeepAlive > 3");
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proto_tree_add_item(tree, hf_msdp_trailing_junk, tvb, offset, length, ENC_NA);
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offset += length;
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}
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break;
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case MSDP_NOTIFICATION:
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/*
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* This was in draft 10, but is reserved in the
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* RFC.
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*/
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dissect_msdp_notification(tvb, pinfo, msdp_tree, &offset, length, length_item);
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break;
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default:
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if (length > 0)
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proto_tree_add_item(msdp_tree, hf_msdp_tlv_contents, tvb, offset, length, ENC_NA);
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offset += length;
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break;
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}
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}
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return tvb_captured_length(tvb);
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}
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/* Both Source-Active and Source-Active Response have the same format
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* with one exception. Encapsulated multicast data is not allowed in
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* SA Response.
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*/
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static void dissect_msdp_sa(tvbuff_t *tvb, packet_info *pinfo,
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proto_tree *tree, int *offset, int length, proto_item *length_item)
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{
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guint32 entries;
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if (length < 1) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for IPv4 Source-Active or Source-Active Response < 5");
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return;
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}
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proto_tree_add_item_ret_uint(tree, hf_msdp_sa_entry_count, tvb, *offset, 1, ENC_BIG_ENDIAN, &entries);
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*offset += 1;
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length -= 1;
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if (length < 4) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for IPv4 Source-Active or Source-Active Response < 5");
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*offset += length;
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return;
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}
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proto_tree_add_item(tree, hf_msdp_sa_rp_addr, tvb, *offset, 4, ENC_BIG_ENDIAN);
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*offset += 4;
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length -= 4;
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/* Put each of the (S,G) entries in their own subtree.
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* This is probably visually better.
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*/
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while (entries-- > 0) {
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proto_tree *entry_tree;
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if (length < 12) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for IPv4 Source-Active or Source-Active Response too short");
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*offset += length;
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return;
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}
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entry_tree = proto_tree_add_subtree_format(tree, tvb, *offset, 12, ett_msdp_sa_entry, NULL,
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"(S,G) block: %s/%u -> %s",
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tvb_ip_to_str(tvb, *offset + 8),
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tvb_get_guint8(tvb, *offset + 3),
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tvb_ip_to_str(tvb, *offset + 4));
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proto_tree_add_item(entry_tree, hf_msdp_sa_reserved, tvb, *offset, 3, ENC_BIG_ENDIAN);
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*offset += 3;
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length -= 3;
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proto_tree_add_item(entry_tree, hf_msdp_sa_sprefix_len, tvb, *offset, 1, ENC_BIG_ENDIAN);
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*offset += 1;
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length -= 1;
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proto_tree_add_item(entry_tree, hf_msdp_sa_group_addr, tvb, *offset, 4, ENC_BIG_ENDIAN);
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*offset += 4;
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length -= 4;
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proto_tree_add_item(entry_tree, hf_msdp_sa_src_addr, tvb, *offset, 4, ENC_BIG_ENDIAN);
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*offset += 4;
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length -= 4;
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}
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/*
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* Check if an encapsulated multicast IPv4 packet follows
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*/
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if (length > 0) {
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proto_tree *enc_tree;
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gint reported_length;
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tvbuff_t *next_tvb;
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enc_tree = proto_tree_add_subtree_format(tree, tvb, *offset, length,
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ett_msdp_sa_enc_data, NULL, "Encapsulated IPv4 packet: %u bytes",
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length);
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reported_length = tvb_reported_length_remaining(tvb, *offset);
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DISSECTOR_ASSERT(reported_length >= 0);
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if (reported_length > length)
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reported_length = length;
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next_tvb = tvb_new_subset_length(tvb, *offset, reported_length);
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/* Set the protocol and information columns read-only so
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* that they reflect the MSDP packet rather than the
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* encapsulated packet.
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*/
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col_set_writable(pinfo->cinfo, COL_PROTOCOL, FALSE);
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col_set_writable(pinfo->cinfo, COL_INFO, FALSE);
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call_dissector(ip_handle, next_tvb, pinfo, enc_tree);
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}
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*offset += length;
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return;
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}
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/* Note: updates *offset */
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static void add_notification_data_ipv4addr(tvbuff_t *tvb, proto_tree *tree, int *offset, int hf_addr)
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{
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proto_tree_add_item(tree, hf_msdp_not_res, tvb, *offset, 3, ENC_BIG_ENDIAN);
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*offset += 3;
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proto_tree_add_item(tree, hf_addr, tvb, *offset, 4, ENC_BIG_ENDIAN);
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*offset += 4;
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return;
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}
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static void dissect_msdp_notification(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int *offset, guint16 tlv_len, proto_item *length_item)
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{
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guint8 error, error_sub;
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const value_string *vals;
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gint reported_length;
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tvbuff_t *next_tvb;
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if (tlv_len < 1) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for Notification < 4");
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return;
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}
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proto_tree_add_item(tree, hf_msdp_not_o, tvb, *offset, 1, ENC_BIG_ENDIAN);
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proto_tree_add_item(tree, hf_msdp_not_error, tvb, *offset, 1, ENC_BIG_ENDIAN);
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error = tvb_get_guint8(tvb, *offset);
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error &= 0x7F; /* Error is 7-bit field. O-bit is bit 8 */
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*offset += 1;
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tlv_len -= 1;
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/* Depending on the Error Code, we collect the correct
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* value_strings for the Error subcode
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*/
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switch (error) {
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case MESSAGE_HEADER_ERROR:
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vals = hdr_error_vals;
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break;
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case SA_REQUEST_ERROR:
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vals = sa_req_error_vals;
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break;
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case SA_MESSAGE_SA_RESPONSE_ERROR:
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vals = sa_msg_error_vals;
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break;
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case FSM_ERROR:
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vals = fsm_error_vals;
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break;
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case HOLD_TIMER_EXPIRED:
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case NOTIFICATION:
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case CEASE:
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vals = sa_unspec_error_vals;
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break;
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default:
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vals = sa_unspec_error_vals;
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break;
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}
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if (tlv_len < 1) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for Notification < 5");
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return;
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}
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error_sub = tvb_get_guint8(tvb, *offset);
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proto_tree_add_uint_format_value(tree, hf_msdp_not_error_sub, tvb, *offset, 1,
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error_sub, "%s (%u)",
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val_to_str_const(error_sub, vals, "<Unknown Error subcode>"),
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error_sub);
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*offset += 1;
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tlv_len -= 1;
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/* Do switch again, this time to dissect the data portion
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* correctly. Ugly.
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*/
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switch (error) {
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case SA_REQUEST_ERROR:
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if (tlv_len < 7) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for Notification SA-Request Error < 12");
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*offset += tlv_len;
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return;
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}
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add_notification_data_ipv4addr(tvb, tree, offset, hf_msdp_not_group_address);
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tlv_len -= 7;
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break;
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case SA_MESSAGE_SA_RESPONSE_ERROR:
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if (error_sub == 0) {
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break;
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} else if (error_sub == 1) {
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if (tlv_len < 1) {
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expert_add_info_format(pinfo, length_item,
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&ei_msdp_tlv_len_too_short,
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"TLV length for Notification SA-Response Invalid Entry Count Error < 6");
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return;
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}
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proto_tree_add_item(tree, hf_msdp_not_entry_count, tvb, *offset, 1, ENC_BIG_ENDIAN);
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*offset += 1;
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tlv_len -= 1;
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|
break;
|
|
} else if (error_sub == 2) {
|
|
if (tlv_len < 7) {
|
|
expert_add_info_format(pinfo, length_item,
|
|
&ei_msdp_tlv_len_too_short,
|
|
"TLV length for Notification SA-Response Invalid RP Address Error < 12");
|
|
*offset += tlv_len;
|
|
return;
|
|
}
|
|
add_notification_data_ipv4addr(tvb, tree, offset, hf_msdp_not_rp_address);
|
|
tlv_len -= 7;
|
|
break;
|
|
} else if (error_sub == 3 || error_sub == 8) {
|
|
if (tlv_len < 7) {
|
|
expert_add_info_format(pinfo, length_item,
|
|
&ei_msdp_tlv_len_too_short,
|
|
"TLV length for Notification SA-Response %s Error < 12",
|
|
(error_sub == 3) ? "Invalid Group Address"
|
|
: "Administrative Scope Boundary Violated");
|
|
*offset += tlv_len;
|
|
return;
|
|
}
|
|
add_notification_data_ipv4addr(tvb, tree, offset, hf_msdp_not_group_address);
|
|
tlv_len -= 7;
|
|
break;
|
|
} else if (error_sub == 4) {
|
|
if (tlv_len < 7) {
|
|
expert_add_info_format(pinfo, length_item,
|
|
&ei_msdp_tlv_len_too_short,
|
|
"TLV length for Notification SA-Response Invalid Source Address Error < 12");
|
|
*offset += tlv_len;
|
|
return;
|
|
}
|
|
add_notification_data_ipv4addr(tvb, tree, offset, hf_msdp_not_source_address);
|
|
tlv_len -= 7;
|
|
break;
|
|
} else if (error_sub == 5) {
|
|
if (tlv_len < 1) {
|
|
expert_add_info_format(pinfo, length_item,
|
|
&ei_msdp_tlv_len_too_short,
|
|
"TLV length for Notification SA-Response Invalid Invalid Sprefix Length Error < 6");
|
|
return;
|
|
}
|
|
proto_tree_add_item(tree, hf_msdp_not_sprefix_len, tvb, *offset, 1, ENC_BIG_ENDIAN);
|
|
*offset += 1;
|
|
tlv_len -= 1;
|
|
break;
|
|
} else if (error_sub == 6) {
|
|
if (tlv_len > 0) {
|
|
reported_length = tvb_reported_length_remaining(tvb, *offset);
|
|
DISSECTOR_ASSERT(reported_length >= 0);
|
|
if (reported_length > tlv_len)
|
|
reported_length = tlv_len;
|
|
next_tvb = tvb_new_subset_length(tvb, *offset, reported_length);
|
|
dissect_msdp(next_tvb, pinfo, tree, NULL);
|
|
}
|
|
*offset += tlv_len;
|
|
tlv_len = 0;
|
|
} else if (error_sub == 7) {
|
|
if (tlv_len > 0) {
|
|
reported_length = tvb_reported_length_remaining(tvb, *offset);
|
|
DISSECTOR_ASSERT(reported_length >= 0);
|
|
if (reported_length > tlv_len)
|
|
reported_length = tlv_len;
|
|
next_tvb = tvb_new_subset_length(tvb, *offset, reported_length);
|
|
dissect_msdp(next_tvb, pinfo, tree, NULL);
|
|
}
|
|
*offset += tlv_len;
|
|
tlv_len = 0;
|
|
break;
|
|
} else {
|
|
if (tlv_len > 0)
|
|
proto_tree_add_item(tree, hf_msdp_unknown_data, tvb, *offset, tlv_len, ENC_NA);
|
|
*offset += tlv_len;
|
|
tlv_len = 0;
|
|
break;
|
|
}
|
|
break;
|
|
case MESSAGE_HEADER_ERROR:
|
|
case NOTIFICATION:
|
|
/* Data contains the message that had an error. Even a
|
|
* broken Notification message causes a Notification
|
|
* message with Error Code set to Notification to be
|
|
* sent back.
|
|
*/
|
|
if (tlv_len > 0) {
|
|
reported_length = tvb_reported_length_remaining(tvb, *offset);
|
|
DISSECTOR_ASSERT(reported_length >= 0);
|
|
if (reported_length > tlv_len)
|
|
reported_length = tlv_len;
|
|
next_tvb = tvb_new_subset_length(tvb, *offset, reported_length);
|
|
dissect_msdp(next_tvb, pinfo, tree, NULL);
|
|
}
|
|
*offset += tlv_len;
|
|
tlv_len = 0;
|
|
break;
|
|
case FSM_ERROR:
|
|
case HOLD_TIMER_EXPIRED:
|
|
case CEASE:
|
|
/* Do nothing. These contain no data */
|
|
break;
|
|
default:
|
|
if (tlv_len > 0)
|
|
proto_tree_add_item(tree, hf_msdp_unknown_data, tvb, *offset, tlv_len, ENC_NA);
|
|
*offset += tlv_len;
|
|
tlv_len = 0;
|
|
break;
|
|
}
|
|
if (tlv_len != 0) {
|
|
expert_add_info_format(pinfo, length_item,
|
|
&ei_msdp_tlv_len_too_long,
|
|
"TLV length too long");
|
|
proto_tree_add_item(tree, hf_msdp_trailing_junk, tvb, *offset, tlv_len, ENC_NA);
|
|
*offset += tlv_len;
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
void
|
|
proto_register_msdp(void)
|
|
{
|
|
static hf_register_info hf[] = {
|
|
{ &hf_msdp_type,
|
|
{ "Type", "msdp.type",
|
|
FT_UINT8, BASE_DEC, VALS(msdp_types), 0,
|
|
"MSDP TLV type", HFILL }
|
|
},
|
|
{ &hf_msdp_length,
|
|
{ "Length", "msdp.length",
|
|
FT_UINT16, BASE_DEC, NULL, 0,
|
|
"MSDP TLV Length", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_entry_count,
|
|
{ "Entry Count", "msdp.sa.entry_count",
|
|
FT_UINT8, BASE_DEC, NULL, 0,
|
|
"MSDP SA Entry Count", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_rp_addr,
|
|
{ "RP Address", "msdp.sa.rp_addr",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"Active source's RP address", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_reserved,
|
|
{ "Reserved", "msdp.sa.reserved",
|
|
FT_UINT24, BASE_HEX, NULL, 0,
|
|
"Transmitted as zeros and ignored by a receiver", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_sprefix_len,
|
|
{ "Sprefix len", "msdp.sa.sprefix_len",
|
|
FT_UINT8, BASE_DEC, NULL, 0,
|
|
"The route prefix length associated with source address", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_group_addr,
|
|
{ "Group Address", "msdp.sa.group_addr",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"The group address the active source has sent data to", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_src_addr,
|
|
{ "Source Address", "msdp.sa.src_addr",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"The IP address of the active source", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_req_res,
|
|
{ "Reserved", "msdp.sa_req.res",
|
|
FT_UINT8, BASE_HEX, NULL, 0,
|
|
"Transmitted as zeros and ignored by a receiver", HFILL }
|
|
},
|
|
{ &hf_msdp_sa_req_group,
|
|
{ "Group Address", "msdp.sa_req.group_addr",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"The group address the MSDP peer is requesting", HFILL }
|
|
},
|
|
{ &hf_msdp_not_o,
|
|
{ "Open-bit", "msdp.not.o",
|
|
FT_UINT8, BASE_HEX, NULL, 0x80,
|
|
"If clear, the connection will be closed", HFILL }
|
|
},
|
|
{ &hf_msdp_not_error,
|
|
{ "Error Code", "msdp.not.error",
|
|
FT_UINT8, BASE_DEC, VALS(error_vals), 0x7F,
|
|
"Indicates the type of Notification", HFILL }
|
|
},
|
|
{ &hf_msdp_not_error_sub,
|
|
{ "Error subcode", "msdp.not.error_sub",
|
|
FT_UINT8, BASE_DEC, NULL, 0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_msdp_not_group_address,
|
|
{ "Group address", "msdp.not.group_address",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"Group address in Notification messages", HFILL }
|
|
},
|
|
{ &hf_msdp_not_rp_address,
|
|
{ "RP address", "msdp.not.rp_address",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"RP address in Notification messages", HFILL }
|
|
},
|
|
{ &hf_msdp_not_source_address,
|
|
{ "Source address", "msdp.not.source_address",
|
|
FT_IPv4, BASE_NONE, NULL, 0,
|
|
"Source address in Notification messages", HFILL }
|
|
},
|
|
{ &hf_msdp_not_res,
|
|
{ "Reserved", "msdp.not.res",
|
|
FT_UINT24, BASE_HEX, NULL, 0,
|
|
"Reserved field in Notification messages", HFILL }
|
|
},
|
|
{ &hf_msdp_not_entry_count,
|
|
{ "Entry Count", "msdp.not.entry_count",
|
|
FT_UINT24, BASE_HEX, NULL, 0,
|
|
"Entry Count in Notification messages", HFILL }
|
|
},
|
|
{ &hf_msdp_not_sprefix_len,
|
|
{ "Sprefix len", "msdp.not.sprefix_len",
|
|
FT_UINT8, BASE_DEC, NULL, 0,
|
|
"Source prefix length in Notification messages", HFILL }
|
|
},
|
|
{ &hf_msdp_tlv_contents,
|
|
{ "TLV contents", "msdp.tlv_contents",
|
|
FT_BYTES, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_msdp_trailing_junk,
|
|
{ "Trailing junk", "msdp.trailing_junk",
|
|
FT_BYTES, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }
|
|
},
|
|
{ &hf_msdp_unknown_data,
|
|
{ "Unknown data", "msdp.unknown_data",
|
|
FT_BYTES, BASE_NONE, NULL, 0,
|
|
NULL, HFILL }
|
|
},
|
|
};
|
|
|
|
static gint *ett[] = {
|
|
&ett_msdp,
|
|
&ett_msdp_sa_entry,
|
|
&ett_msdp_sa_enc_data,
|
|
&ett_msdp_not_data,
|
|
};
|
|
|
|
static ei_register_info ei[] = {
|
|
{ &ei_msdp_tlv_len_too_long,
|
|
{ "msdp.tlv_len.too_long", PI_PROTOCOL, PI_WARN,
|
|
"TLV length too long", EXPFILL }
|
|
},
|
|
{ &ei_msdp_tlv_len_too_short,
|
|
{ "msdp.tlv_len.too_short", PI_MALFORMED, PI_ERROR,
|
|
"TLV length too short", EXPFILL }
|
|
},
|
|
};
|
|
|
|
expert_module_t *expert_msdp;
|
|
|
|
proto_msdp = proto_register_protocol("Multicast Source Discovery Protocol",
|
|
"MSDP", "msdp");
|
|
|
|
proto_register_field_array(proto_msdp, hf, array_length(hf));
|
|
proto_register_subtree_array(ett, array_length(ett));
|
|
expert_msdp = expert_register_protocol(proto_msdp);
|
|
expert_register_field_array(expert_msdp, ei, array_length(ei));
|
|
}
|
|
|
|
void
|
|
proto_reg_handoff_msdp(void)
|
|
{
|
|
dissector_handle_t msdp_handle;
|
|
|
|
msdp_handle = create_dissector_handle(dissect_msdp, proto_msdp);
|
|
dissector_add_uint_with_preference("tcp.port", MSDP_PORT, msdp_handle);
|
|
|
|
ip_handle = find_dissector_add_dependency("ip", proto_msdp);
|
|
}
|
|
|
|
/*
|
|
* Editor modelines
|
|
*
|
|
* Local Variables:
|
|
* c-basic-offset: 8
|
|
* tab-width: 8
|
|
* indent-tabs-mode: nil
|
|
* End:
|
|
*
|
|
* ex: set shiftwidth=8 tabstop=8 expandtab:
|
|
* :indentSize=8:tabSize=8:noTabs=true:
|
|
*/
|