/* packet-dec-bpdu.c * Routines for DEC BPDU (DEC Spanning Tree Protocol) disassembly * * $Id: packet-dec-bpdu.c,v 1.6 2001/01/25 06:14:14 guy Exp $ * * Copyright 2001 Paul Ionescu * * Ethereal - Network traffic analyzer * By Gerald Combs * 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 #ifdef HAVE_SYS_TYPES_H # include #endif #ifdef HAVE_NETINET_IN_H # include #endif #include #include #include #include "packet.h" #include "resolv.h" #include "etypes.h" #include "ppptypes.h" /* Offsets of fields within a BPDU */ #define BPDU_DEC_CODE 0 #define BPDU_TYPE 1 #define BPDU_VERSION 2 #define BPDU_FLAGS 3 #define BPDU_ROOT_PRI 4 #define BPDU_ROOT_MAC 6 #define BPDU_ROOT_PATH_COST 12 #define BPDU_BRIDGE_PRI 14 #define BPDU_BRIDGE_MAC 16 #define BPDU_PORT_IDENTIFIER 22 #define BPDU_MESSAGE_AGE 23 #define BPDU_HELLO_TIME 24 #define BPDU_MAX_AGE 25 #define BPDU_FORWARD_DELAY 26 #define DEC_BPDU_SIZE 27 static int proto_dec_bpdu = -1; static gint ett_dec_bpdu = -1; static void dissect_dec_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { guint8 protocol_identifier; guint8 protocol_version; guint8 bpdu_type; guint8 flags; proto_tree *bpdu_tree; proto_item *ti; if (check_col(pinfo->fd, COL_PROTOCOL)) { col_set_str(pinfo->fd, COL_PROTOCOL, "DEC_STP"); } if (check_col(pinfo->fd, COL_INFO)) { col_clear(pinfo->fd, COL_INFO); } bpdu_type = tvb_get_guint8(tvb, BPDU_TYPE); flags=tvb_get_guint8(tvb,BPDU_FLAGS); if (check_col(pinfo->fd, COL_INFO)) { if (bpdu_type == 25) col_add_fstr(pinfo->fd, COL_INFO, "Hello Packet"); else if (bpdu_type == 0x02) col_add_fstr(pinfo->fd, COL_INFO, "Topology Change Notification"); } tvb_set_reported_length(tvb, DEC_BPDU_SIZE); if (tree) { protocol_identifier = tvb_get_guint8(tvb, BPDU_DEC_CODE); protocol_version = tvb_get_guint8(tvb, BPDU_VERSION); ti = proto_tree_add_protocol_format(tree, proto_dec_bpdu, tvb, 0, DEC_BPDU_SIZE, "DEC Spanning Tree Protocol"); bpdu_tree = proto_item_add_subtree(ti, ett_dec_bpdu); proto_tree_add_text(bpdu_tree, tvb, BPDU_DEC_CODE, 1, "Protocol ID: 0x%02x (%s)", protocol_identifier, protocol_identifier==0xe1?"DEC Spanning Tree Protocol": "Unknown protocol, the dissection may be wrong"); proto_tree_add_text(bpdu_tree, tvb, BPDU_TYPE,1, "BPDU Type: %u (%s)", bpdu_type, (bpdu_type==25?"Hello Packet":(bpdu_type==2?"Topology change notice":"Unknown"))); proto_tree_add_text(bpdu_tree, tvb, BPDU_VERSION,1, "BPDU Version: %u (%s)", protocol_version,protocol_version==1?"DEC STP Version 1":"Unknown Version"); proto_tree_add_text(bpdu_tree, tvb, BPDU_FLAGS,1, "Flags: 0x%02x",flags); if (flags & 0x80) proto_tree_add_text(bpdu_tree, tvb, BPDU_FLAGS, 1, " 1... .... Use short timers"); if (flags & 0x02) proto_tree_add_text(bpdu_tree, tvb, BPDU_FLAGS, 1, " .... ..1. Topology Change Acknowledgment"); if (flags & 0x01) proto_tree_add_text(bpdu_tree, tvb, BPDU_FLAGS, 1, " .... ...1 Topology Change"); proto_tree_add_text(bpdu_tree, tvb, BPDU_ROOT_PRI,2, "Root priority: %u", tvb_get_ntohs(tvb,BPDU_ROOT_PRI)); proto_tree_add_text(bpdu_tree, tvb, BPDU_ROOT_MAC,6, "Root MAC: %s", ether_to_str(tvb_get_ptr(tvb,BPDU_ROOT_MAC,6))); proto_tree_add_text(bpdu_tree, tvb, BPDU_ROOT_PATH_COST,2, "Root path cost: %u", tvb_get_ntohs(tvb,BPDU_ROOT_PATH_COST)); proto_tree_add_text(bpdu_tree, tvb, BPDU_BRIDGE_PRI,2, "Root priority: %u", tvb_get_ntohs(tvb,BPDU_BRIDGE_PRI)); proto_tree_add_text(bpdu_tree, tvb, BPDU_BRIDGE_MAC,6, "Root MAC: %s", ether_to_str(tvb_get_ptr(tvb,BPDU_BRIDGE_MAC,6))); proto_tree_add_text(bpdu_tree, tvb, BPDU_PORT_IDENTIFIER,1, "Port identifier: %u", tvb_get_guint8(tvb,BPDU_PORT_IDENTIFIER)); proto_tree_add_text(bpdu_tree, tvb, BPDU_MESSAGE_AGE,1, "Age: %u", tvb_get_guint8(tvb,BPDU_MESSAGE_AGE)); proto_tree_add_text(bpdu_tree, tvb, BPDU_HELLO_TIME,1, "Hello time: %u", tvb_get_guint8(tvb,BPDU_HELLO_TIME)); proto_tree_add_text(bpdu_tree, tvb, BPDU_MAX_AGE,1, "Max Age: %u", tvb_get_guint8(tvb,BPDU_MAX_AGE)); proto_tree_add_text(bpdu_tree, tvb, BPDU_FORWARD_DELAY,1, "Forward Delay: %u", tvb_get_guint8(tvb,BPDU_FORWARD_DELAY)); } } void proto_register_dec_bpdu(void) { static gint *ett[] = { &ett_dec_bpdu, }; proto_dec_bpdu = proto_register_protocol("DEC Spanning Tree Protocol", "DEC_STP", "dec_stp"); proto_register_subtree_array(ett, array_length(ett)); } void proto_reg_handoff_dec_bpdu(void) { dissector_add("ethertype", ETHERTYPE_DEC_LB, dissect_dec_bpdu, proto_dec_bpdu); dissector_add("ppp.protocol", PPP_DEC_LB, dissect_dec_bpdu, proto_dec_bpdu); }