+++ /dev/null
-/* packet-msdp.c
- * Routines for Multicast Source Discovery Protocol (MSDP) dissection.
- * draft-ietf-msdp-spec-10.txt
- *
- * Copyright 2001, Heikki Vatiainen <hessu@cs.tut.fi>
- *
- * $Id$
- *
- * Ethereal - Network traffic analyzer
- * By Gerald Combs <gerald@ethereal.com>
- * 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.
- */
-
-#ifdef HAVE_CONFIG_H
-# include "config.h"
-#endif
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <glib.h>
-
-#include <epan/packet.h>
-
-/* MSDP message types. The messages are TLV (Type-Length-Value) encoded */
-enum { MSDP_SA = 1,
- MSDP_SA_REQ,
- MSDP_SA_RSP,
- MSDP_KEEP_ALIVE,
- MSDP_NOTIFICATION,
-
- /* Theses are only assigned in MSDP spec. Their use is specifed
- * elsewhere */
- MSDP_TRACE_IN_PROGRESS,
- MSDP_TRACE_REPLY
-};
-
-static const value_string msdp_types[] = {
- { MSDP_SA, "IPv4 Source-Active" },
- { MSDP_SA_REQ, "IPv4 Source-Active Request" },
- { MSDP_SA_RSP, "IPv4 Source-Active Response" },
- { MSDP_KEEP_ALIVE, "KeepAlive" },
- { MSDP_NOTIFICATION, "Notification" },
-
- { MSDP_TRACE_IN_PROGRESS, "MSDP traceroute in progresss" },
- { MSDP_TRACE_REPLY, "MSDP traceroute reply" },
- { 0, NULL },
-};
-
-
-/* Error codes */
-enum { MESSAGE_HEADER_ERROR = 1,
- SA_REQUEST_ERROR,
- SA_MESSAGE_SA_RESPONSE_ERROR,
- HOLD_TIMER_EXPIRED,
- FSM_ERROR,
- NOTIFICATION,
- CEASE
-};
-
-static const value_string error_vals[] = {
- { MESSAGE_HEADER_ERROR, "Message Header Error" },
- { SA_REQUEST_ERROR, "SA-Request Error" },
- { SA_MESSAGE_SA_RESPONSE_ERROR, "SA-Message/SA-Response Error" },
- { HOLD_TIMER_EXPIRED, "Hold Timer Expired" },
- { FSM_ERROR, "Finite State Machine Error" },
- { NOTIFICATION, "Notification" },
- { CEASE, "Cease" },
- { 0, NULL },
-};
-
-
-/* Message Header Error subcodes */
-static const value_string hdr_error_vals[] = {
- { 0, "Unspecific" },
- { 2, "Bad Message Length" },
- { 3, "Bad Message Type" },
- { 0, NULL },
-};
-
-/* SA-Request Error subcodes (the O-bit is always clear) */
-static const value_string sa_req_error_vals[] = {
- { 0, "Unspecific" },
- { 1, "Invalid Group" },
- { 0, NULL },
-};
-
-/* SA-Message/SA-Response Error subcodes */
-static const value_string sa_msg_error_vals[] = {
- { 0, "Unspecific" },
- { 1, "Invalid Entry Count" },
- { 2, "Invalid RP Address" },
- { 3, "Invalid Group Address" },
- { 4, "Invalid Source Address" },
- { 5, "Invalid Sprefix Length" },
- { 6, "Looping SA (Self is RP)" },
- { 7, "Unknown Encapsulation" },
- { 8, "Administrative Scope Boundary Violated" },
- { 0, NULL },
-};
-
-/* Finite State Machine Error subcodes (the O-bit is always clear) */
-static const value_string fsm_error_vals[] = {
- { 0, "Unspecific" },
- { 1, "Unexpected Message Type FSM Error" },
- { 0, NULL },
-};
-
-/*
- * Hold Timer Expired subcodes (the O-bit is always clear):
- * Notification subcodes (the O-bit is always clear):
- * Cease subcodes (the O-bit is always clear):
- *
- * These have only "Unspecific" specified.
- */
-static const value_string sa_unspec_error_vals[] = {
- { 0, "Unspecific" },
- { 0, NULL },
-};
-
-
-/* Initialize the protocol and registered fields */
-static int proto_msdp = -1;
-static int hf_msdp_type = -1;
-static int hf_msdp_length = -1;
-
-static int hf_msdp_sa_entry_count = -1;
-static int hf_msdp_sa_rp_addr = -1;
-static int hf_msdp_sa_reserved = -1;
-static int hf_msdp_sa_sprefix_len = -1;
-static int hf_msdp_sa_group_addr = -1;
-static int hf_msdp_sa_src_addr = -1;
-
-static int hf_msdp_sa_req_res = -1;
-static int hf_msdp_sa_req_group = -1;
-
-static int hf_msdp_not_o = -1;
-static int hf_msdp_not_error = -1;
-static int hf_msdp_not_error_sub = -1;
-
-static int hf_msdp_not_ipv4 = -1;
-static int hf_msdp_not_res = -1;
-static int hf_msdp_not_entry_count = -1;
-static int hf_msdp_not_sprefix_len = -1;
-
-
-static gint ett_msdp = -1;
-static gint ett_msdp_sa_entry = -1;
-static gint ett_msdp_sa_enc_data = -1;
-static gint ett_msdp_not_data = -1;
-
-
-static dissector_handle_t ip_handle;
-
-
-static void
-dissect_msdp_sa(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree,
- int *offset, int len);
-static void
-dissect_msdp_notification(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int *offset, guint16 tlv_len);
-
-
-static void
-dissect_msdp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
-{
- proto_item *ti;
- proto_tree *msdp_tree;
- int offset;
-
- if (check_col(pinfo->cinfo, COL_PROTOCOL))
- col_set_str(pinfo->cinfo, COL_PROTOCOL, "MSDP");
-
- if (check_col(pinfo->cinfo, COL_INFO))
- col_set_str(pinfo->cinfo, COL_INFO, val_to_str(tvb_get_guint8(tvb, 0),
- msdp_types,
- "<Unknown MSDP message type>"));
-
- if (tree) {
- guint8 type;
- guint16 length;
-
- ti = proto_tree_add_item(tree, proto_msdp, tvb, 0, -1, FALSE);
- msdp_tree = proto_item_add_subtree(ti, ett_msdp);
-
- offset = 0;
- while (tvb_reported_length_remaining(tvb, offset) >= 3) {
- type = tvb_get_guint8(tvb, offset);
- length = tvb_get_ntohs(tvb, offset + 1);
- if (length < 3)
- break;
- proto_tree_add_uint(msdp_tree, hf_msdp_type, tvb, offset, 1, type);
- proto_tree_add_uint(msdp_tree, hf_msdp_length, tvb, offset + 1, 2, length);
- offset += 3;
- length -= 3;
-
- switch (type) {
- case MSDP_SA:
- case MSDP_SA_RSP:
- dissect_msdp_sa(tvb, pinfo, msdp_tree, &offset,
- length);
- break;
- case MSDP_SA_REQ:
- proto_tree_add_item(msdp_tree, hf_msdp_sa_req_res, tvb, offset, 1, FALSE);
- proto_tree_add_item(msdp_tree, hf_msdp_sa_req_group, tvb, offset + 1, 4, FALSE);
- offset += 5;
- break;
- case MSDP_NOTIFICATION:
- dissect_msdp_notification(tvb, pinfo, msdp_tree, &offset, length);
- break;
- default:
- if (length > 0)
- proto_tree_add_text(msdp_tree, tvb, offset, length, "TLV contents");
- offset += length;
- break;
- }
- }
-
- if (tvb_length_remaining(tvb, offset) > 0)
- proto_tree_add_text(msdp_tree, tvb, offset,
- -1, "Trailing junk");
- }
-
- return;
-}
-
-/* Both Source-Active and Source-Active Response have the same format
- * with one exception. Encapsulated multicast data is not allowed in
- * SA Response.
- */
-static void dissect_msdp_sa(tvbuff_t *tvb, packet_info *pinfo,
- proto_tree *tree, int *offset, int length)
-{
- guint8 entries;
- guint32 rp_addr;
-
- if (length < 1)
- return;
- entries = tvb_get_guint8(tvb, *offset);
- proto_tree_add_uint(tree, hf_msdp_sa_entry_count, tvb, *offset, 1, entries);
- *offset += 1;
- length -= 1;
-
- if (length < 4) {
- *offset += length;
- length = 0;
- return;
- }
- tvb_memcpy(tvb, (guint8 *)&rp_addr, *offset, 4);
- proto_tree_add_item(tree, hf_msdp_sa_rp_addr, tvb, *offset, 4, FALSE);
- *offset += 4;
- length -= 4;
-
- /* Put each of the (S,G) entries in their own subtree.
- * This is probably visually better.
- */
- while (entries-- > 0) {
- proto_item *ei;
- proto_tree *entry_tree;
-
- if (length < 12) {
- *offset += length;
- length = 0;
- return;
- }
- ei = proto_tree_add_text(tree, tvb, *offset, 12, "(S,G) block: %s/%u -> %s",
- ip_to_str(tvb_get_ptr(tvb, *offset + 8, 4)),
- tvb_get_guint8(tvb, *offset + 3),
- ip_to_str(tvb_get_ptr(tvb, *offset + 4, 4)));
- entry_tree = proto_item_add_subtree(ei, ett_msdp_sa_entry);
-
- proto_tree_add_item(entry_tree, hf_msdp_sa_reserved, tvb, *offset, 3, FALSE);
- *offset += 3;
- length -= 3;
- proto_tree_add_item(entry_tree, hf_msdp_sa_sprefix_len, tvb, *offset, 1, FALSE);
- *offset += 1;
- length -= 1;
- proto_tree_add_item(entry_tree, hf_msdp_sa_group_addr, tvb, *offset, 4, FALSE);
- *offset += 4;
- length -= 4;
- proto_tree_add_item(entry_tree, hf_msdp_sa_src_addr, tvb, *offset, 4, FALSE);
- *offset += 4;
- length -= 4;
- }
-
- /*
- * Check if an encapsulated multicast IPv4 packet follows
- */
- if (length > 0) {
- proto_item *ei;
- proto_tree *enc_tree;
- gint available_length, reported_length;
- tvbuff_t *next_tvb;
-
- ei = proto_tree_add_text(tree, tvb, *offset, length,
- "Encapsulated IPv4 packet: %u bytes",
- length);
- enc_tree = proto_item_add_subtree(ei, ett_msdp_sa_enc_data);
-
- available_length = tvb_length_remaining(tvb, *offset);
- reported_length = tvb_reported_length_remaining(tvb, *offset);
- g_assert(available_length >= 0);
- g_assert(reported_length >= 0);
- if (available_length > reported_length)
- available_length = reported_length;
- if (available_length > length)
- available_length = length;
- if (reported_length > length)
- reported_length = length;
-
- next_tvb = tvb_new_subset(tvb, *offset, available_length,
- reported_length);
- /* Set the information columns read-only so that they
- * reflect the MSDP packet rather than the
- * encapsulated packet.
- */
- col_set_writable(pinfo->cinfo, FALSE);
- call_dissector(ip_handle, next_tvb, pinfo, enc_tree);
- }
- *offset += length;
-
- return;
-}
-
-/* Note: updates *offset */
-static void add_notification_data_ipv4addr(tvbuff_t *tvb, proto_tree *tree, int *offset, const char *addrtype)
-{
- guint32 ipaddr;
-
- proto_tree_add_item(tree, hf_msdp_not_res, tvb, *offset, 3, FALSE);
- *offset += 3;
- tvb_memcpy(tvb, (guint8 *)&ipaddr, *offset, 4);
- proto_tree_add_ipv4_format(tree, hf_msdp_not_ipv4, tvb, *offset, 4, ipaddr,
- "%s: %s", addrtype, ip_to_str((guint8 *)&ipaddr));
- *offset += 4;
-
- return;
-}
-
-static void dissect_msdp_notification(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int *offset, guint16 tlv_len)
-{
- guint8 error, error_sub;
- const value_string *vals;
-
- proto_tree_add_item(tree, hf_msdp_not_o, tvb, *offset, 1, FALSE);
- proto_tree_add_item(tree, hf_msdp_not_error, tvb, *offset, 1, FALSE);
- error = tvb_get_guint8(tvb, *offset);
- error &= 0x7F; /* Error is 7-bit field. O-bit is bit 8 */
- *offset += 1;
-
- /* Depending on the Error Code, we collect the correct
- * value_strings for the Error subcode
- */
- switch (error) {
- case MESSAGE_HEADER_ERROR:
- vals = hdr_error_vals;
- break;
- case SA_REQUEST_ERROR:
- vals = sa_req_error_vals;
- break;
- case SA_MESSAGE_SA_RESPONSE_ERROR:
- vals = sa_msg_error_vals;
- break;
- case FSM_ERROR:
- vals = fsm_error_vals;
- break;
- case HOLD_TIMER_EXPIRED:
- case NOTIFICATION:
- case CEASE:
- vals = sa_unspec_error_vals;
- break;
- default:
- vals = sa_unspec_error_vals;
- break;
- }
-
- error_sub = tvb_get_guint8(tvb, *offset);
- proto_tree_add_uint_format(tree, hf_msdp_not_error_sub, tvb, *offset, 1,
- error_sub, "Error subcode: %s (%u)",
- val_to_str(error_sub, vals, "<Unknown Error subcode>"),
- error_sub);
- *offset += 1;
-
- /* Do switch again, this time to dissect the data portion
- * correctly. Ugly.
- */
- switch (error) {
- tvbuff_t *next_tvb;
- case SA_REQUEST_ERROR:
- add_notification_data_ipv4addr(tvb, tree, offset, "Group address");
- break;
- case SA_MESSAGE_SA_RESPONSE_ERROR:
- if (error_sub == 0) {
- break;
- } else if (error_sub == 1) {
- proto_tree_add_item(tree, hf_msdp_not_entry_count, tvb, *offset, 1, FALSE);
- *offset += 1;
- break;
- } else if (error_sub == 2) {
- add_notification_data_ipv4addr(tvb, tree, offset, "RP address");
- break;
- } else if (error_sub == 3 || error_sub == 8) {
- add_notification_data_ipv4addr(tvb, tree, offset, "Group address");
- break;
- } else if (error_sub == 4) {
- add_notification_data_ipv4addr(tvb, tree, offset, "Source address");
- break;
- } else if (error_sub == 5) {
- proto_tree_add_item(tree, hf_msdp_not_sprefix_len, tvb, *offset, 1, FALSE);
- *offset += 1;
- break;
- } else if (error_sub == 6) {
- /* No break, causes fall through to next label */
- } else if (error_sub == 7) {
- proto_tree_add_text(tree, tvb, *offset, tlv_len - 5,
- "Packet with unknown encapsulation: %u bytes",
- tlv_len - 5);
- *offset += tlv_len - 5;
- break;
- } else {
- proto_tree_add_text(tree, tvb, *offset, tlv_len - 5,
- "<Unknown data>: %u bytes",
- tlv_len -5);
- *offset += tlv_len - 5;
- break;
- }
- /* Fall through */
- 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.
- */
- next_tvb = tvb_new_subset(tvb, *offset, -1, -1);
- dissect_msdp(next_tvb, pinfo, tree);
- break;
- case FSM_ERROR:
- case HOLD_TIMER_EXPIRED:
- case CEASE:
- /* Do nothing. These contain no data */
- break;
- default:
- if (tlv_len - 5 > 0)
- proto_tree_add_text(tree, tvb, *offset, tlv_len - 5,
- "<Unknown data>: %u bytes",
- tlv_len -5);
- *offset += tlv_len - 5;
- break;
- }
-
- 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, 0, 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, 0, 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, 0, 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, 0, 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 subode", "msdp.not.error_sub",
- FT_UINT8, BASE_DEC, NULL, 0,
- "Error subcode", HFILL }
- },
- { &hf_msdp_not_ipv4,
- { "IPv4 address", "msdp.not.ipv4",
- FT_IPv4, 0, NULL, 0,
- "Group/RP/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 }
- },
- };
-
- static gint *ett[] = {
- &ett_msdp,
- &ett_msdp_sa_entry,
- &ett_msdp_sa_enc_data,
- &ett_msdp_not_data,
- };
-
- 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));
-}
-
-void
-proto_reg_handoff_msdp(void)
-{
- dissector_handle_t msdp_handle;
-
- msdp_handle = create_dissector_handle(dissect_msdp, proto_msdp);
- dissector_add("tcp.port", 639, msdp_handle);
-
- ip_handle = find_dissector("ip");
-
- return;
-}
git.samba.org / obnox / wireshark / wip.git / blobdiff