/* packet-dec-bpdu.c * Routines for DEC BPDU (DEC Spanning Tree Protocol) disassembly * * $Id: packet-dec-bpdu.c,v 1.15 2002/08/28 21:00:12 jmayer 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 #include #include #include #include #include #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 /* Flag bits */ #define BPDU_FLAGS_SHORT_TIMERS 0x80 #define BPDU_FLAGS_TCACK 0x02 #define BPDU_FLAGS_TC 0x01 static int proto_dec_bpdu = -1; static int hf_dec_bpdu_proto_id = -1; static int hf_dec_bpdu_type = -1; static int hf_dec_bpdu_version_id = -1; static int hf_dec_bpdu_flags = -1; static int hf_dec_bpdu_flags_short_timers = -1; static int hf_dec_bpdu_flags_tcack = -1; static int hf_dec_bpdu_flags_tc = -1; static int hf_dec_bpdu_root_pri = -1; static int hf_dec_bpdu_root_mac = -1; static int hf_dec_bpdu_root_cost = -1; static int hf_dec_bpdu_bridge_pri = -1; static int hf_dec_bpdu_bridge_mac = -1; static int hf_dec_bpdu_port_id = -1; static int hf_dec_bpdu_msg_age = -1; static int hf_dec_bpdu_hello_time = -1; static int hf_dec_bpdu_max_age = -1; static int hf_dec_bpdu_forward_delay = -1; static gint ett_dec_bpdu = -1; static gint ett_dec_bpdu_flags = -1; static const value_string protocol_id_vals[] = { { 0xe1, "DEC Spanning Tree Protocol" }, { 0, NULL } }; #define BPDU_TYPE_TOPOLOGY_CHANGE 2 #define BPDU_TYPE_HELLO 25 static const value_string bpdu_type_vals[] = { { BPDU_TYPE_TOPOLOGY_CHANGE, "Topology Change Notification" }, { BPDU_TYPE_HELLO, "Hello Packet" }, { 0, NULL } }; static const char initial_sep[] = " ("; static const char cont_sep[] = ", "; #define APPEND_BOOLEAN_FLAG(flag, item, string) \ if(flag){ \ if(item) \ proto_item_append_text(item, string, sep); \ sep = cont_sep; \ } static void dissect_dec_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) { guint8 protocol_version; guint8 bpdu_type; guint8 flags; proto_tree *bpdu_tree; proto_tree *flags_tree; proto_item *ti; const char *sep; if (check_col(pinfo->cinfo, COL_PROTOCOL)) { col_set_str(pinfo->cinfo, COL_PROTOCOL, "DEC_STP"); } if (check_col(pinfo->cinfo, COL_INFO)) { col_clear(pinfo->cinfo, COL_INFO); } bpdu_type = tvb_get_guint8(tvb, BPDU_TYPE); if (check_col(pinfo->cinfo, COL_INFO)) { col_add_str(pinfo->cinfo, COL_INFO, val_to_str(bpdu_type, bpdu_type_vals, "Unknown BPDU type (%u)")); } set_actual_length(tvb, DEC_BPDU_SIZE); if (tree) { ti = proto_tree_add_item(tree, proto_dec_bpdu, tvb, 0, DEC_BPDU_SIZE, FALSE); bpdu_tree = proto_item_add_subtree(ti, ett_dec_bpdu); protocol_version = tvb_get_guint8(tvb, BPDU_VERSION); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_proto_id, tvb, BPDU_DEC_CODE, 1, FALSE); proto_tree_add_uint(bpdu_tree, hf_dec_bpdu_type, tvb, BPDU_TYPE, 1, bpdu_type); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_version_id, tvb, BPDU_VERSION, 1, FALSE); flags = tvb_get_guint8(tvb, BPDU_FLAGS); ti = proto_tree_add_uint(bpdu_tree, hf_dec_bpdu_flags, tvb, BPDU_FLAGS, 1, flags); flags_tree = proto_item_add_subtree(ti, ett_dec_bpdu_flags); sep = initial_sep; APPEND_BOOLEAN_FLAG(flags & BPDU_FLAGS_SHORT_TIMERS, ti, "%sUse short timers"); proto_tree_add_boolean(flags_tree, hf_dec_bpdu_flags_short_timers, tvb, BPDU_FLAGS, 1, flags); APPEND_BOOLEAN_FLAG(flags & BPDU_FLAGS_TCACK, ti, "%sTopology Change Acknowledgment"); proto_tree_add_boolean(flags_tree, hf_dec_bpdu_flags_tcack, tvb, BPDU_FLAGS, 1, flags); APPEND_BOOLEAN_FLAG(flags & BPDU_FLAGS_TC, ti, "%sTopology Change"); proto_tree_add_boolean(flags_tree, hf_dec_bpdu_flags_tc, tvb, BPDU_FLAGS, 1, flags); if (sep != initial_sep) { /* We put something in; put in the terminating ")" */ proto_item_append_text(ti, ")"); } proto_tree_add_item(bpdu_tree, hf_dec_bpdu_root_pri, tvb, BPDU_ROOT_PRI, 2, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_root_mac, tvb, BPDU_ROOT_MAC, 6, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_root_cost, tvb, BPDU_ROOT_PATH_COST, 2, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_bridge_pri, tvb, BPDU_BRIDGE_PRI, 2, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_bridge_mac, tvb, BPDU_BRIDGE_MAC, 6, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_port_id, tvb, BPDU_PORT_IDENTIFIER, 1, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_msg_age, tvb, BPDU_MESSAGE_AGE, 1, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_hello_time, tvb, BPDU_HELLO_TIME, 1, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_max_age, tvb, BPDU_MAX_AGE, 1, FALSE); proto_tree_add_item(bpdu_tree, hf_dec_bpdu_forward_delay, tvb, BPDU_FORWARD_DELAY, 1, FALSE); } } static const true_false_string yesno = { "Yes", "No" }; void proto_register_dec_bpdu(void) { static hf_register_info hf[] = { { &hf_dec_bpdu_proto_id, { "Protocol Identifier", "dec_stp.protocol", FT_UINT8, BASE_HEX, VALS(&protocol_id_vals), 0x0, "", HFILL }}, { &hf_dec_bpdu_type, { "BPDU Type", "dec_stp.type", FT_UINT8, BASE_DEC, VALS(&bpdu_type_vals), 0x0, "", HFILL }}, { &hf_dec_bpdu_version_id, { "BPDU Version", "dec_stp.version", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_flags, { "BPDU flags", "dec_stp.flags", FT_UINT8, BASE_HEX, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_flags_short_timers, { "Use short timers", "dec_stp.flags.short_timers", FT_BOOLEAN, 8, TFS(&yesno), BPDU_FLAGS_SHORT_TIMERS, "", HFILL }}, { &hf_dec_bpdu_flags_tcack, { "Topology Change Acknowledgment", "dec_stp.flags.tcack", FT_BOOLEAN, 8, TFS(&yesno), BPDU_FLAGS_TCACK, "", HFILL }}, { &hf_dec_bpdu_flags_tc, { "Topology Change", "dec_stp.flags.tc", FT_BOOLEAN, 8, TFS(&yesno), BPDU_FLAGS_TC, "", HFILL }}, { &hf_dec_bpdu_root_pri, { "Root Priority", "dec_stp.root.pri", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_root_mac, { "Root MAC", "dec_stp.root.mac", FT_ETHER, BASE_NONE, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_root_cost, { "Root Path Cost", "dec_stp.root.cost", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_bridge_pri, { "Bridge Priority", "dec_stp.bridge.pri", FT_UINT16, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_bridge_mac, { "Bridge MAC", "dec_stp.bridge.mac", FT_ETHER, BASE_NONE, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_port_id, { "Port identifier", "dec_stp.port", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_msg_age, { "Message Age", "dec_stp.msg_age", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_hello_time, { "Hello Time", "dec_stp.hello", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_max_age, { "Max Age", "dec_stp.max_age", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, { &hf_dec_bpdu_forward_delay, { "Forward Delay", "dec_stp.forward", FT_UINT8, BASE_DEC, NULL, 0x0, "", HFILL }}, }; static gint *ett[] = { &ett_dec_bpdu, &ett_dec_bpdu_flags, }; proto_dec_bpdu = proto_register_protocol("DEC Spanning Tree Protocol", "DEC_STP", "dec_stp"); proto_register_field_array(proto_dec_bpdu, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); } void proto_reg_handoff_dec_bpdu(void) { dissector_handle_t dec_bpdu_handle; dec_bpdu_handle = create_dissector_handle(dissect_dec_bpdu, proto_dec_bpdu); dissector_add("ethertype", ETHERTYPE_DEC_LB, dec_bpdu_handle); dissector_add("chdlctype", ETHERTYPE_DEC_LB, dec_bpdu_handle); dissector_add("ppp.protocol", PPP_DEC_LB, dec_bpdu_handle); }