diff options
author | Gilbert Ramirez <gram@alumni.rice.edu> | 2004-07-18 18:06:47 +0000 |
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committer | Gilbert Ramirez <gram@alumni.rice.edu> | 2004-07-18 18:06:47 +0000 |
commit | 669db206cb1f270046ad400fff7655e20c63e723 (patch) | |
tree | 4eff24a2e16c8963e497e1fc575f35e6af59bd26 /epan/dissectors/packet-msdp.c | |
parent | ae46c27a38700af669ef907491081f09df6f6b2c (diff) |
Move dissectors to epan/dissectors directory.
Also move ncp222.py, x11-fields, process-x11-fields.pl,
make-reg-dotc, and make-reg-dotc.py.
Adjust #include lines in files that include packet-*.h
files.
svn path=/trunk/; revision=11410
Diffstat (limited to 'epan/dissectors/packet-msdp.c')
-rw-r--r-- | epan/dissectors/packet-msdp.c | 585 |
1 files changed, 585 insertions, 0 deletions
diff --git a/epan/dissectors/packet-msdp.c b/epan/dissectors/packet-msdp.c new file mode 100644 index 0000000000..cb15ca0c3d --- /dev/null +++ b/epan/dissectors/packet-msdp.c @@ -0,0 +1,585 @@ +/* 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; +} |