diff options
Diffstat (limited to 'epan/dissectors/packet-bpdu.c')
| -rw-r--r-- | epan/dissectors/packet-bpdu.c | 1382 |
1 files changed, 1382 insertions, 0 deletions
diff --git a/epan/dissectors/packet-bpdu.c b/epan/dissectors/packet-bpdu.c new file mode 100644 index 00000000..734e9831 --- /dev/null +++ b/epan/dissectors/packet-bpdu.c @@ -0,0 +1,1382 @@ +/* packet-bpdu.c + * Routines for BPDU (Spanning Tree Protocol) disassembly + * + * Copyright 1999 Christophe Tronche <ch.tronche@computer.org> + * + * Wireshark - Network traffic analyzer + * By Gerald Combs <gerald@wireshark.org> + * Copyright 1998 Gerald Combs + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "config.h" + +#include <epan/packet.h> +#include <epan/llcsaps.h> +#include <epan/chdlctypes.h> +#include <epan/etypes.h> +#include <epan/addr_resolv.h> +#include <epan/prefs.h> +#include <epan/expert.h> +#include <epan/cisco_pid.h> + +/* Offsets of fields within a BPDU */ + +#define BPDU_IDENTIFIER 0 +#define BPDU_VERSION_IDENTIFIER 2 +#define BPDU_TYPE 3 +#define BPDU_FLAGS 4 +#define BPDU_ROOT_IDENTIFIER 5 +#define BPDU_ROOT_PATH_COST 13 +#define BPDU_BRIDGE_IDENTIFIER 17 +#define BPDU_PORT_IDENTIFIER 25 +#define BPDU_MESSAGE_AGE 27 +#define BPDU_MAX_AGE 29 +#define BPDU_HELLO_TIME 31 +#define BPDU_FORWARD_DELAY 33 +#define BPDU_VERSION_1_LENGTH 35 +#define BPDU_VERSION_3_LENGTH 36 +#define BPDU_MST_CONFIG_FORMAT_SELECTOR 38 +#define BPDU_MST_CONFIG_NAME 39 +#define BPDU_MST_CONFIG_REVISION_LEVEL 71 +#define BPDU_MST_CONFIG_DIGEST 73 +#define BPDU_CIST_INTERNAL_ROOT_PATH_COST 89 +#define BPDU_CIST_BRIDGE_IDENTIFIER 93 +#define BPDU_CIST_REMAINING_HOPS 101 +#define BPDU_MSTI 102 + +#define BPDU_PVST_TLV 36 + +#define MSTI_FLAGS 0 +#define MSTI_REGIONAL_ROOT 1 +#define MSTI_INTERNAL_ROOT_PATH_COST 9 +#define MSTI_BRIDGE_IDENTIFIER_PRIORITY 13 +#define MSTI_PORT_IDENTIFIER_PRIORITY 14 +#define MSTI_REMAINING_HOPS 15 + + +#define CONF_BPDU_SIZE 35 +#define TC_BPDU_SIZE 4 +#define MST_BPDU_SIZE 38 +#define VERSION_3_STATIC_LENGTH 64 +#define MSTI_MESSAGE_SIZE 16 + +/* Values for the Alternative MSTI format */ + +#define ALT_BPDU_CIST_BRIDGE_IDENTIFIER 89 +#define ALT_BPDU_CIST_INTERNAL_ROOT_PATH_COST 97 + +#define ALT_MSTI_MSTID 0 +#define ALT_MSTI_FLAGS 2 +#define ALT_MSTI_REGIONAL_ROOT 3 +#define ALT_MSTI_INTERNAL_ROOT_PATH_COST 11 +#define ALT_MSTI_BRIDGE_IDENTIFIER 15 +#define ALT_MSTI_PORT_IDENTIFIER 23 +#define ALT_MSTI_REMAINING_HOPS 25 + +#define ALT_MSTI_MESSAGE_SIZE 26 + +/* Flag bits */ + +#define BPDU_FLAGS_TCACK 0x80 +#define BPDU_FLAGS_AGREEMENT 0x40 +#define BPDU_FLAGS_FORWARDING 0x20 +#define BPDU_FLAGS_LEARNING 0x10 +#define BPDU_FLAGS_PORT_ROLE_MASK 0x0C +#define BPDU_FLAGS_PORT_ROLE_SHIFT 2 +#define BPDU_FLAGS_PROPOSAL 0x02 +#define BPDU_FLAGS_TC 0x01 + +void proto_register_bpdu(void); +void proto_reg_handoff_bpdu(void); + +static int proto_bpdu = -1; +static int hf_bpdu_proto_id = -1; +static int hf_bpdu_version_id = -1; +static int hf_bpdu_type = -1; +static int hf_bpdu_flags = -1; +static int hf_bpdu_flags_tcack = -1; +static int hf_bpdu_flags_agreement = -1; +static int hf_bpdu_flags_forwarding = -1; +static int hf_bpdu_flags_learning = -1; +static int hf_bpdu_flags_port_role = -1; +static int hf_bpdu_flags_proposal = -1; +static int hf_bpdu_flags_tc = -1; +static int hf_bpdu_root_prio = -1; +static int hf_bpdu_root_sys_id_ext = -1; +static int hf_bpdu_root_mac = -1; +static int hf_bpdu_root_cost = -1; +static int hf_bpdu_bridge_prio = -1; +static int hf_bpdu_bridge_sys_id_ext = -1; +static int hf_bpdu_bridge_mac = -1; +static int hf_bpdu_port_id = -1; +static int hf_bpdu_msg_age = -1; +static int hf_bpdu_max_age = -1; +static int hf_bpdu_hello_time = -1; +static int hf_bpdu_forward_delay = -1; +static int hf_bpdu_version_1_length = -1; +static int hf_bpdu_version_3_length = -1; +static int hf_bpdu_mst_config_format_selector = -1; +static int hf_bpdu_mst_config_name = -1; +static int hf_bpdu_mst_config_revision_level = -1; +static int hf_bpdu_mst_config_digest = -1; +static int hf_bpdu_cist_internal_root_path_cost = -1; +static int hf_bpdu_cist_bridge_prio = -1; +static int hf_bpdu_cist_bridge_sys_id_ext = -1; +static int hf_bpdu_cist_bridge_mac = -1; +static int hf_bpdu_cist_remaining_hops = -1; +static int hf_bpdu_msti_flags = -1; +static int hf_bpdu_msti_id = -1; +static int hf_bpdu_msti_id_FFF = -1; +static int hf_bpdu_mst_priority = -1; +static int hf_bpdu_msti_regional_root_id = -1; +static int hf_bpdu_msti_regional_root_mac = -1; +static int hf_bpdu_msti_internal_root_path_cost = -1; +static int hf_bpdu_msti_bridge_identifier_priority = -1; +static int hf_bpdu_msti_port_identifier_priority = -1; +static int hf_bpdu_msti_port_id = -1; +static int hf_bpdu_msti_bridge_id = -1; +static int hf_bpdu_msti_bridge_id_priority = -1; +static int hf_bpdu_msti_bridge_id_mac = -1; +static int hf_bpdu_msti_remaining_hops = -1; +static int hf_bpdu_version_4_length = -1; +static int hf_bpdu_spt_config_format_selector = -1; +static int hf_bpdu_spt_config_name = -1; +static int hf_bpdu_spt_config_revision_level = -1; +static int hf_bpdu_spt_config_digest = -1; +static int hf_bpdu_flags_agree_num = -1; +static int hf_bpdu_flags_dagree_num = -1; +static int hf_bpdu_flags_agree_valid = -1; +static int hf_bpdu_flags_restricted_role = -1; +static int hf_bpdu_spt_agreement_digest = -1; +static int hf_bpdu_agreement_digest_format_id = -1; +static int hf_bpdu_agreement_digest_format_capabilities = -1; +static int hf_bpdu_agreement_digest_convention_id = -1; +static int hf_bpdu_agreement_digest_convention_capabilities = -1; +static int hf_bpdu_agreement_digest_edge_count = -1; + +static int hf_bpdu_pvst_tlvtype = -1; +static int hf_bpdu_pvst_tlvlength = -1; +static int hf_bpdu_pvst_tlvvalue = -1; +static int hf_bpdu_pvst_tlv_origvlan = -1; + +static gint ett_bpdu = -1; +static gint ett_bpdu_flags = -1; +static gint ett_root_id = -1; +static gint ett_bridge_id = -1; +static gint ett_mstp = -1; +static gint ett_msti = -1; +static gint ett_cist_bridge_id = -1; +static gint ett_spt = -1; +static gint ett_aux_mcid = -1; +static gint ett_agreement = -1; +static gint ett_bpdu_pvst_tlv = -1; + +static expert_field ei_pvst_tlv_length_invalid = EI_INIT; +static expert_field ei_pvst_tlv_origvlan_missing = EI_INIT; +static expert_field ei_pvst_tlv_truncated = EI_INIT; +static expert_field ei_pvst_tlv_unknown = EI_INIT; +static expert_field ei_bpdu_type = EI_INIT; +static expert_field ei_bpdu_version_support = EI_INIT; + + +static gboolean bpdu_use_system_id_extensions = TRUE; + +static dissector_handle_t gvrp_handle; +static dissector_handle_t gmrp_handle; + +static dissector_handle_t bpdu_handle = NULL; +static dissector_handle_t bpdu_cisco_handle = NULL; + +static const value_string protocol_id_vals[] = { + { 0, "Spanning Tree Protocol" }, + { 0, NULL } +}; + +#define BPDU_PVST_TLV_ORIGVLAN 0 /* Originating VLAN TLV in Cisco (R)PVST+ BPDUs */ + +static const value_string bpdu_pvst_tlv_vals[] = { + { BPDU_PVST_TLV_ORIGVLAN, "Originating VLAN" }, + { 0, NULL } +}; + + +#define BPDU_TYPE_CONF 0x00 /* STP Configuration BPDU */ +#define BPDU_TYPE_RST 0x02 /* RST BPDU (or MST) */ +#define BPDU_TYPE_TOPOLOGY_CHANGE 0x80 /* STP TCN (Topology change notify) BPDU */ + +static const value_string bpdu_type_vals[] = { + { BPDU_TYPE_CONF, "Configuration" }, + { BPDU_TYPE_RST, "Rapid/Multiple Spanning Tree" }, + { BPDU_TYPE_TOPOLOGY_CHANGE, "Topology Change Notification" }, + { 0, NULL } +}; + +#define PROTO_VERSION_STP 0 +#define PROTO_VERSION_RSTP 2 +#define PROTO_VERSION_MSTP 3 +#define PROTO_VERSION_SPB 4 + +#define MSTI_FORMAT_UNKNOWN 0 +#define MSTI_FORMAT_IEEE_8021S 1 +#define MSTI_FORMAT_ALTERNATIVE 2 + +static const value_string version_id_vals[] = { + { PROTO_VERSION_STP, "Spanning Tree" }, + { PROTO_VERSION_RSTP, "Rapid Spanning Tree" }, + { PROTO_VERSION_MSTP, "Multiple Spanning Tree" }, + { PROTO_VERSION_SPB, "Shortest Path Tree" }, + { 0, NULL} +}; +static const value_string role_vals[] = { + { 1, "Alternate or Backup" }, + { 2, "Root" }, + { 3, "Designated" }, + { 0, NULL } +}; + +static const char initial_sep[] = " ("; +static const char cont_sep[] = ", "; + +static void +dissect_bpdu_pvst_tlv(packet_info *pinfo, proto_tree *tree, tvbuff_t *tvb) { + gboolean pvst_tlv_origvlan_present = FALSE; + guint16 tlv_type, tlv_length; + int offset = BPDU_PVST_TLV; + proto_item * ti = NULL; + proto_item * tlv_length_item = NULL; + proto_tree * tlv_tree = NULL; + + if (tvb_reported_length_remaining(tvb, offset) < 4) /* TLV Type and Length fields occupy 4 bytes in total */ + expert_add_info(pinfo, tree, &ei_pvst_tlv_truncated); + + while (tvb_reported_length_remaining(tvb, offset) >= 4) { /* TLV Type and Length fields occupy 4 bytes in total */ + tlv_type = tvb_get_ntohs(tvb, offset); + tlv_length = tvb_get_ntohs(tvb, offset + 2); + + tlv_tree = proto_tree_add_subtree(tree, tvb, offset, 4 + tlv_length, + ett_bpdu_pvst_tlv, &ti, + val_to_str(tlv_type, bpdu_pvst_tlv_vals, "Unknown TLV type: 0x%04x")); + + proto_tree_add_item(tlv_tree, hf_bpdu_pvst_tlvtype, tvb, offset, 2, ENC_BIG_ENDIAN); + tlv_length_item = proto_tree_add_item(tlv_tree, hf_bpdu_pvst_tlvlength, + tvb, offset + 2, 2, ENC_BIG_ENDIAN); + + if (tvb_reported_length_remaining(tvb, offset + 4) < tlv_length) { + expert_add_info(pinfo, tlv_length_item, &ei_pvst_tlv_truncated); + break; + } + + offset += 4; + + switch (tlv_type) { + case BPDU_PVST_TLV_ORIGVLAN: + if (tlv_length == 2) { /* Originating VLAN ID must be 2 bytes long */ + proto_item_append_text(ti, " (PVID): %u", tvb_get_ntohs(tvb, offset)); + proto_tree_add_item(tlv_tree, hf_bpdu_pvst_tlv_origvlan, tvb, offset, tlv_length, ENC_BIG_ENDIAN); + pvst_tlv_origvlan_present = TRUE; + } + else + expert_add_info(pinfo, tlv_length_item, &ei_pvst_tlv_length_invalid); + break; + + default: + proto_tree_add_item(tlv_tree, hf_bpdu_pvst_tlvvalue, tvb, offset, tlv_length, ENC_NA); + expert_add_info(pinfo, tlv_tree, &ei_pvst_tlv_unknown); + break; + } + + offset += tlv_length; + } + + if (pvst_tlv_origvlan_present == FALSE) /* If a (R)PVST+ BPDU lacks the Originating VLAN TLV, it is malformed */ + expert_add_info(pinfo, tree, &ei_pvst_tlv_origvlan_missing); +} + +static void +dissect_bpdu(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean is_bpdu_pvst) +{ + guint16 protocol_identifier; + guint8 protocol_version_identifier; + guint8 bpdu_type; + guint8 flags; + guint16 root_identifier_bridge_priority; + guint16 root_identifier_system_id_extension = 0; + const gchar *root_identifier_mac_str; + guint32 root_path_cost; + guint16 bridge_identifier_bridge_priority; + guint16 bridge_identifier_system_id_extension = 0; + const gchar *bridge_identifier_mac_str; + guint16 port_identifier; + double message_age; + double max_age; + double hello_time; + double forward_delay; + guint8 version_1_length; + guint16 version_3_length; + guint16 version_4_length = 0; + guint16 bpdu_version_4_length = 0; + guint8 config_format_selector; + guint16 cist_bridge_identifier_bridge_priority; + guint16 cist_bridge_identifier_system_id_extension = 0; + const gchar *cist_bridge_identifier_mac_str; + guint32 msti_regional_root_mstid, msti_regional_root_priority; + const gchar *msti_regional_root_mac_str; + guint16 msti_bridge_identifier_priority, msti_port_identifier_priority; + int total_msti_length, offset, msti_format; + int msti_length_remaining; + + int spt_offset = 0; + + int MCID_LEN = 51; + guint8 spt_agree_data = 0; + + proto_tree *bpdu_tree; + proto_tree *mstp_tree, *msti_tree, *spt_tree = NULL, *aux_mcid_tree = NULL, *agreement_tree = NULL; + proto_item *bpdu_item; + proto_item *agreement_item, *proto_id_item, *type_item; + proto_tree *root_id_tree; + proto_tree *bridge_id_tree; + proto_tree *cist_bridge_id_tree; + const char *sep; + + static int * const bpdu_flags[] = { + &hf_bpdu_flags_tcack, + &hf_bpdu_flags_tc, + NULL + }; + + static int * const rst_flags[] = { + &hf_bpdu_flags_tcack, + &hf_bpdu_flags_agreement, + &hf_bpdu_flags_forwarding, + &hf_bpdu_flags_learning, + &hf_bpdu_flags_port_role, + &hf_bpdu_flags_proposal, + &hf_bpdu_flags_tc, + NULL + }; + + /* GARP application frames require special interpretation of the + destination address field; otherwise, they will be mistaken as + BPDU frames. + Fortunately, they can be recognized by checking the first 6 octets + of the destination address, which are in the range from + 01-80-C2-00-00-20 to 01-80-C2-00-00-2F. + + Yes - we *do* need to check the destination address type; + on Linux cooked captures, there *is* no destination address, + so it's AT_NONE. */ + if (pinfo->dl_dst.type == AT_ETHER) { + const guint8 *dstaddr; + + dstaddr = (const guint8 *)pinfo->dl_dst.data; + if(dstaddr[0] == 0x01 && dstaddr[1] == 0x80 && + dstaddr[2] == 0xC2 && dstaddr[3] == 0x00 && + dstaddr[4] == 0x00 && ((dstaddr[5] == 0x0D) || ((dstaddr[5] & 0xF0) == 0x20))) { + + switch (dstaddr[5]) { + + case 0x20: + /* for GMRP */ + call_dissector(gmrp_handle, tvb, pinfo, tree); + return; + + case 0x21: + case 0x0D: + /* for GVRP */ + call_dissector(gvrp_handle, tvb, pinfo, tree); + return; + } + col_set_str(pinfo->cinfo, COL_PROTOCOL, "GARP"); + /* Generic Attribute Registration Protocol */ + + col_add_fstr(pinfo->cinfo, COL_INFO, + "Unknown GARP application (0x%02X)", + dstaddr[5]); + + return; + } + } + + col_set_str(pinfo->cinfo, COL_PROTOCOL, "STP"); /* Spanning Tree Protocol */ + col_clear(pinfo->cinfo, COL_INFO); + + bpdu_type = tvb_get_guint8(tvb, BPDU_TYPE); + + protocol_version_identifier = tvb_get_guint8(tvb, BPDU_VERSION_IDENTIFIER); + + switch (bpdu_type) { + + case BPDU_TYPE_CONF: + case BPDU_TYPE_RST: + flags = tvb_get_guint8(tvb, BPDU_FLAGS); + root_identifier_bridge_priority = tvb_get_ntohs(tvb,BPDU_ROOT_IDENTIFIER); + if (bpdu_use_system_id_extensions ) { + root_identifier_system_id_extension = root_identifier_bridge_priority & 0x0fff; + root_identifier_bridge_priority &= 0xf000; + } + root_identifier_mac_str = tvb_ether_to_str(pinfo->pool, tvb, BPDU_ROOT_IDENTIFIER + 2); + root_path_cost = tvb_get_ntohl(tvb, BPDU_ROOT_PATH_COST); + port_identifier = tvb_get_ntohs(tvb, BPDU_PORT_IDENTIFIER); + break; + + default: + /* Squelch GCC complaints. */ + flags = 0; + root_identifier_bridge_priority = 0; + root_identifier_mac_str = NULL; + root_path_cost = 0; + port_identifier = 0; + break; + } + + switch (bpdu_type) { + + case BPDU_TYPE_CONF: + if (bpdu_use_system_id_extensions ) { + col_add_fstr(pinfo->cinfo, COL_INFO, + "Conf. %sRoot = %d/%d/%s Cost = %d Port = 0x%04x", + flags & 0x1 ? "TC + " : "", + root_identifier_bridge_priority, + root_identifier_system_id_extension, + root_identifier_mac_str, + root_path_cost, port_identifier); + } else { + col_add_fstr(pinfo->cinfo, COL_INFO, + "Conf. %sRoot = %d/%s Cost = %d Port = 0x%04x", + flags & 0x1 ? "TC + " : "", + root_identifier_bridge_priority, root_identifier_mac_str, + root_path_cost, port_identifier); + } + break; + + case BPDU_TYPE_TOPOLOGY_CHANGE: + col_set_str(pinfo->cinfo, COL_INFO, "Topology Change Notification"); + break; + + case BPDU_TYPE_RST: + if (bpdu_use_system_id_extensions ) { + col_add_fstr(pinfo->cinfo, COL_INFO, + "%sT. %sRoot = %d/%d/%s Cost = %d Port = 0x%04x", + protocol_version_identifier == 3 ? "MS": + (protocol_version_identifier == 4 ? "SP":"RS"), + flags & 0x1 ? "TC + " : "", + root_identifier_bridge_priority, + root_identifier_system_id_extension, + root_identifier_mac_str, + root_path_cost, port_identifier); + } else { + col_add_fstr(pinfo->cinfo, COL_INFO, + "%sT. %sRoot = %d/%s Cost = %d Port = 0x%04x", + protocol_version_identifier == 3 ? "MS": + (protocol_version_identifier == 4 ? "SP":"RS"), + flags & 0x1 ? "TC + " : "", + root_identifier_bridge_priority, root_identifier_mac_str, + root_path_cost, port_identifier); + } + break; + + default: + col_add_fstr(pinfo->cinfo, COL_INFO, "Unknown BPDU type (%u)", bpdu_type); + break; + } + + bpdu_item = proto_tree_add_protocol_format(tree, proto_bpdu, tvb, 0, -1, + "Spanning Tree Protocol"); + bpdu_tree = proto_item_add_subtree(bpdu_item, ett_bpdu); + + protocol_identifier = tvb_get_ntohs(tvb, BPDU_IDENTIFIER); + proto_tree_add_uint(bpdu_tree, hf_bpdu_proto_id, tvb, BPDU_IDENTIFIER, 2, + protocol_identifier); + + proto_id_item = proto_tree_add_uint(bpdu_tree, hf_bpdu_version_id, tvb, + BPDU_VERSION_IDENTIFIER, 1, + protocol_version_identifier); + switch (protocol_version_identifier) { + + case 0: + break; + + case 2: + case 3: + case 4: + break; + + default: + expert_add_info(pinfo, proto_id_item, &ei_bpdu_version_support); + break; + } + type_item = proto_tree_add_uint(bpdu_tree, hf_bpdu_type, tvb, BPDU_TYPE, 1, bpdu_type); + + if (bpdu_type == BPDU_TYPE_TOPOLOGY_CHANGE) { + set_actual_length(tvb, TC_BPDU_SIZE); + return; + } + + if (bpdu_type != BPDU_TYPE_CONF && bpdu_type != BPDU_TYPE_RST) { + /* Unknown BPDU type - just display the rest of the PDU as data */ + expert_add_info(pinfo, type_item, &ei_bpdu_type); + return; + } + + bridge_identifier_bridge_priority = tvb_get_ntohs(tvb, BPDU_BRIDGE_IDENTIFIER); + if (bpdu_use_system_id_extensions ) { + bridge_identifier_system_id_extension = bridge_identifier_bridge_priority & 0x0fff; + bridge_identifier_bridge_priority &= 0xf000; + } + bridge_identifier_mac_str = tvb_ether_to_str(pinfo->pool, tvb, BPDU_BRIDGE_IDENTIFIER + 2); + + if (bpdu_type == BPDU_TYPE_RST) { + proto_tree_add_bitmask_value_with_flags(bpdu_tree, tvb, BPDU_FLAGS, hf_bpdu_flags, ett_bpdu_flags, rst_flags, flags, BMT_NO_FALSE|BMT_NO_TFS); + } else { + proto_tree_add_bitmask_value_with_flags(bpdu_tree, tvb, BPDU_FLAGS, hf_bpdu_flags, ett_bpdu_flags, bpdu_flags, flags, BMT_NO_FALSE|BMT_NO_TFS); + } + + /* add Identifier with format based on preference value + * bpdu_use_system_id_extensions + * */ + if (bpdu_use_system_id_extensions) { + root_id_tree = proto_tree_add_subtree_format(bpdu_tree, tvb, + BPDU_ROOT_IDENTIFIER, 8, + ett_root_id, NULL, + "Root Identifier: %d / %d / %s", + root_identifier_bridge_priority, + root_identifier_system_id_extension, + root_identifier_mac_str); + proto_tree_add_uint(root_id_tree, hf_bpdu_root_prio, tvb, + BPDU_ROOT_IDENTIFIER , 1, + root_identifier_bridge_priority); + proto_tree_add_uint(root_id_tree, hf_bpdu_root_sys_id_ext, tvb, + BPDU_ROOT_IDENTIFIER , 2, + root_identifier_system_id_extension); + proto_tree_add_item(root_id_tree, hf_bpdu_root_mac, tvb, + BPDU_ROOT_IDENTIFIER + 2, 6, ENC_NA); + + } else { + root_id_tree = proto_tree_add_subtree_format(bpdu_tree, tvb, + BPDU_ROOT_IDENTIFIER, 8, + ett_root_id, NULL, + "Root Identifier: %d / %s", + root_identifier_bridge_priority, + root_identifier_mac_str); + proto_tree_add_uint(root_id_tree, hf_bpdu_root_prio, tvb, + BPDU_ROOT_IDENTIFIER , 2, + root_identifier_bridge_priority); + proto_tree_add_item(root_id_tree, hf_bpdu_root_mac, tvb, + BPDU_ROOT_IDENTIFIER + 2, 6, ENC_NA); + } + /* end of Identifier formatting */ + + proto_tree_add_uint(bpdu_tree, hf_bpdu_root_cost, tvb, + BPDU_ROOT_PATH_COST, 4, root_path_cost); + + /* add Identifier with format based on preference value + * bpdu_use_system_id_extensions + * */ + if (bpdu_use_system_id_extensions) { + bridge_id_tree = proto_tree_add_subtree_format(bpdu_tree, tvb, + BPDU_BRIDGE_IDENTIFIER, 8, + ett_bridge_id, NULL, + "Bridge Identifier: %d / %d / %s", + bridge_identifier_bridge_priority, + bridge_identifier_system_id_extension, + bridge_identifier_mac_str); + proto_tree_add_uint(bridge_id_tree, hf_bpdu_bridge_prio, tvb, + BPDU_BRIDGE_IDENTIFIER , 1, + bridge_identifier_bridge_priority); + proto_tree_add_uint(bridge_id_tree, hf_bpdu_bridge_sys_id_ext, tvb, + BPDU_BRIDGE_IDENTIFIER , 2, + bridge_identifier_system_id_extension); + proto_tree_add_item(bridge_id_tree, hf_bpdu_bridge_mac, tvb, + BPDU_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + } else { + bridge_id_tree = proto_tree_add_subtree_format(bpdu_tree, tvb, + BPDU_BRIDGE_IDENTIFIER, 8, + ett_bridge_id, NULL, + "Bridge Identifier: %d / %s", + bridge_identifier_bridge_priority, + bridge_identifier_mac_str); + proto_tree_add_uint(bridge_id_tree, hf_bpdu_bridge_prio, tvb, + BPDU_BRIDGE_IDENTIFIER , 2, + bridge_identifier_bridge_priority); + proto_tree_add_item(bridge_id_tree, hf_bpdu_bridge_mac, tvb, + BPDU_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + } + /* end of Identifier formatting */ + + proto_tree_add_uint(bpdu_tree, hf_bpdu_port_id, tvb, + BPDU_PORT_IDENTIFIER, 2, port_identifier); + message_age = tvb_get_ntohs(tvb, BPDU_MESSAGE_AGE) / 256.0; + proto_tree_add_double(bpdu_tree, hf_bpdu_msg_age, tvb, BPDU_MESSAGE_AGE, 2, + message_age); + max_age = tvb_get_ntohs(tvb, BPDU_MAX_AGE) / 256.0; + proto_tree_add_double(bpdu_tree, hf_bpdu_max_age, tvb, BPDU_MAX_AGE, 2, + max_age); + hello_time = tvb_get_ntohs(tvb, BPDU_HELLO_TIME) / 256.0; + proto_tree_add_double(bpdu_tree, hf_bpdu_hello_time, tvb, + BPDU_HELLO_TIME, 2, hello_time); + forward_delay = tvb_get_ntohs(tvb, BPDU_FORWARD_DELAY) / 256.0; + proto_tree_add_double(bpdu_tree, hf_bpdu_forward_delay, tvb, + BPDU_FORWARD_DELAY, 2, forward_delay); + + if (bpdu_type == BPDU_TYPE_CONF) { + if (is_bpdu_pvst) + dissect_bpdu_pvst_tlv(pinfo, bpdu_tree, tvb); + + /* Nothing more in this BPDU */ + set_actual_length(tvb, CONF_BPDU_SIZE); + return; + } + + /* RST or MST BPDU */ + version_1_length = tvb_get_guint8(tvb, BPDU_VERSION_1_LENGTH); + proto_tree_add_uint(bpdu_tree, hf_bpdu_version_1_length, tvb, + BPDU_VERSION_1_LENGTH, 1, version_1_length); + /* Is this an MST BPDU? */ + if (protocol_version_identifier >= 3 && version_1_length == 0 && + tvb_reported_length(tvb) >= 102) { + /* + * OK, it passes the "Protocol Identifier is 0000 0000 + * 0000 0000", "Protocol Version Identifier is 3 or + * greater", "BPDU Type is 0000 0010", "contains 102 or + * more octets", and "a Version 1 Length of 0" tests. + */ + version_3_length = tvb_get_ntohs(tvb, BPDU_VERSION_3_LENGTH); + proto_tree_add_uint(bpdu_tree, hf_bpdu_version_3_length, tvb, + BPDU_VERSION_3_LENGTH, 2, version_3_length); + + /* + * Check the Version 3 Length, and see whether it's a + * multiple of the MSTI Configuration Message length. Also + * check the config_format_selector because some MST BPDU's + * have BPDU_VERSION_3_LENGTH set to 0 and use the + * field BPDU_MST_CONFIG_FORMAT_SELECTOR as a length-field + * for the MSTI data. + */ + config_format_selector = tvb_get_guint8(tvb, BPDU_MST_CONFIG_FORMAT_SELECTOR); + if (version_3_length != 0) { + msti_format = MSTI_FORMAT_IEEE_8021S; + if (version_3_length >= VERSION_3_STATIC_LENGTH) { + total_msti_length = version_3_length - VERSION_3_STATIC_LENGTH; + } else { + /* + * XXX - there appears to be an ambiguity in the 802.3Q-2003 + * standard and at least some of the 802.3s drafts. + * + * The "Version 3 Length" field is defined to be "the number of + * octets taken by the parameters that follow in the BPDU", but + * it's spoken of as "representing an integral number, from 0 to + * 64 inclusive, of MSTI Configuration Messages". + * + * According to mail from a member of the stds-802-1@ieee.org list, + * the latter of those is just saying that the length must not have + * a value that implies that there's a partial MSTI message in the + * packet; it's still in units of octets, not messages. + * + * However, it appears that Cisco's C3550 software (C3550-I5Q3L2-M, + * Version 12.1(12c)EA1) might be sending out lengths in units of + * messages. + * + * This length can't be the number of octets taken by the parameters + * that follow in the BPDU, because it's less than the fixed-length + * portion of those parameters, so we assume the length is a count of + * messages. + */ + total_msti_length = version_3_length * MSTI_MESSAGE_SIZE; + } + } else { + if (tvb_reported_length(tvb) == (guint)config_format_selector + MST_BPDU_SIZE + 1 ) { + msti_format = MSTI_FORMAT_ALTERNATIVE; + total_msti_length = config_format_selector - VERSION_3_STATIC_LENGTH; + } else { + /* + * XXX - Unknown MSTI format, since version_3_length is 0 + * lets assume there are no msti instances in the packet. + */ + msti_format = MSTI_FORMAT_UNKNOWN; + total_msti_length = 0; + } + } + if (protocol_version_identifier == 3) { + set_actual_length(tvb, BPDU_MSTI + total_msti_length); + } + + mstp_tree = proto_tree_add_subtree(bpdu_tree, tvb, BPDU_VERSION_3_LENGTH, + -1, ett_mstp, NULL, "MST Extension"); + + proto_tree_add_item(mstp_tree, hf_bpdu_mst_config_format_selector, tvb, + BPDU_MST_CONFIG_FORMAT_SELECTOR, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(mstp_tree, hf_bpdu_mst_config_name, tvb, + BPDU_MST_CONFIG_NAME, 32, ENC_ASCII|ENC_NA); + + proto_tree_add_item(mstp_tree, hf_bpdu_mst_config_revision_level, tvb, + BPDU_MST_CONFIG_REVISION_LEVEL, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(mstp_tree, hf_bpdu_mst_config_digest, tvb, + BPDU_MST_CONFIG_DIGEST, 16, ENC_NA); + + switch(msti_format) { + + case MSTI_FORMAT_IEEE_8021S: + proto_tree_add_item(mstp_tree, hf_bpdu_cist_internal_root_path_cost, tvb, + BPDU_CIST_INTERNAL_ROOT_PATH_COST, 4, ENC_BIG_ENDIAN); + + cist_bridge_identifier_bridge_priority = tvb_get_ntohs(tvb,BPDU_CIST_BRIDGE_IDENTIFIER); + cist_bridge_identifier_mac_str = tvb_ether_to_str(pinfo->pool, tvb, BPDU_CIST_BRIDGE_IDENTIFIER + 2); + + /* add Identifier with format based on preference value + * bpdu_use_system_id_extensions + * */ + if (bpdu_use_system_id_extensions ) { + cist_bridge_identifier_system_id_extension = cist_bridge_identifier_bridge_priority & 0x0fff; + cist_bridge_identifier_bridge_priority &= 0xf000; + + cist_bridge_id_tree = proto_tree_add_subtree_format(mstp_tree, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER, 8, + ett_cist_bridge_id, NULL, + "CIST Bridge Identifier: %d / %d / %s", + cist_bridge_identifier_bridge_priority, + cist_bridge_identifier_system_id_extension, + cist_bridge_identifier_mac_str); + proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER , 1, + cist_bridge_identifier_bridge_priority); + proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_sys_id_ext, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER , 2, + cist_bridge_identifier_system_id_extension); + proto_tree_add_item(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + + } else { + cist_bridge_id_tree = proto_tree_add_subtree_format(mstp_tree, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER, 8, + ett_cist_bridge_id, NULL, + "CIST Bridge Identifier: %d / %s", + cist_bridge_identifier_bridge_priority, + cist_bridge_identifier_mac_str); + proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER , 2, + cist_bridge_identifier_bridge_priority); + proto_tree_add_item(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac, tvb, + BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + } + /* end of Identifier formatting */ + + break; + + case MSTI_FORMAT_ALTERNATIVE: + cist_bridge_identifier_bridge_priority = tvb_get_ntohs(tvb,ALT_BPDU_CIST_BRIDGE_IDENTIFIER); + cist_bridge_identifier_mac_str = tvb_ether_to_str(pinfo->pool, tvb, ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2); + + /* add Identifier with format based on preference value + * bpdu_use_system_id_extensions + * */ + if (bpdu_use_system_id_extensions ) { + cist_bridge_identifier_system_id_extension = cist_bridge_identifier_bridge_priority & 0x0fff; + cist_bridge_identifier_bridge_priority &= 0xf000; + + cist_bridge_id_tree = proto_tree_add_subtree_format(mstp_tree, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER, 8, + ett_cist_bridge_id, NULL, + "CIST Bridge Identifier: %d / %d / %s", + cist_bridge_identifier_bridge_priority, + cist_bridge_identifier_system_id_extension, + cist_bridge_identifier_mac_str); + proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER , 1, + cist_bridge_identifier_bridge_priority); + proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_sys_id_ext, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER , 2, + cist_bridge_identifier_system_id_extension); + proto_tree_add_item(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + } else { + cist_bridge_id_tree = proto_tree_add_subtree_format(mstp_tree, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER, 8, + ett_cist_bridge_id, NULL, + "CIST Bridge Identifier: %d / %s", + cist_bridge_identifier_bridge_priority, + cist_bridge_identifier_mac_str); + proto_tree_add_uint(cist_bridge_id_tree, hf_bpdu_cist_bridge_prio, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER , 2, + cist_bridge_identifier_bridge_priority); + proto_tree_add_item(cist_bridge_id_tree, hf_bpdu_cist_bridge_mac, tvb, + ALT_BPDU_CIST_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + } + /* end of Identifier formatting */ + + proto_tree_add_item(mstp_tree, hf_bpdu_cist_internal_root_path_cost, tvb, + ALT_BPDU_CIST_INTERNAL_ROOT_PATH_COST, 4, ENC_BIG_ENDIAN); + + break; + } + + proto_tree_add_item(mstp_tree, hf_bpdu_cist_remaining_hops, tvb, + BPDU_CIST_REMAINING_HOPS, 1, ENC_BIG_ENDIAN); + /* MSTI messages */ + offset = BPDU_MSTI; + msti_length_remaining = total_msti_length; + while (msti_length_remaining > 0) { + switch(msti_format) { + + case MSTI_FORMAT_IEEE_8021S: + msti_regional_root_mstid = tvb_get_guint8(tvb, offset+ MSTI_REGIONAL_ROOT); + msti_regional_root_priority = (msti_regional_root_mstid &0xf0) << 8; + msti_regional_root_mstid = ((msti_regional_root_mstid & 0x0f) << 8) + + tvb_get_guint8(tvb, offset+ MSTI_REGIONAL_ROOT+1); + msti_regional_root_mac_str = tvb_ether_to_str(pinfo->pool, tvb, offset + MSTI_REGIONAL_ROOT + 2); + + msti_tree = proto_tree_add_subtree_format(mstp_tree, tvb, offset, 16, ett_msti, NULL, + "MSTID %d, Regional Root Identifier %d / %s", + msti_regional_root_mstid, + msti_regional_root_priority, + msti_regional_root_mac_str); + + /* flags */ + proto_tree_add_bitmask_with_flags(msti_tree, tvb, offset+MSTI_FLAGS, hf_bpdu_msti_flags, ett_bpdu_flags, rst_flags, ENC_NA, BMT_NO_FALSE|BMT_NO_TFS); + + /* pri, MSTID, Regional root */ + proto_tree_add_item(msti_tree, hf_bpdu_mst_priority, tvb, offset + MSTI_REGIONAL_ROOT, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(msti_tree, hf_bpdu_msti_id_FFF, tvb, offset + MSTI_REGIONAL_ROOT, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(msti_tree, hf_bpdu_msti_regional_root_mac, tvb, + offset + MSTI_REGIONAL_ROOT + 2, 6, ENC_NA); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_internal_root_path_cost, tvb, + offset+MSTI_INTERNAL_ROOT_PATH_COST, 4, ENC_BIG_ENDIAN); + + msti_bridge_identifier_priority = tvb_get_guint8(tvb, offset+MSTI_BRIDGE_IDENTIFIER_PRIORITY) >> 4; + msti_port_identifier_priority = tvb_get_guint8(tvb, offset+MSTI_PORT_IDENTIFIER_PRIORITY) >> 4; + + proto_tree_add_uint(msti_tree, hf_bpdu_msti_bridge_identifier_priority, tvb, + offset+MSTI_BRIDGE_IDENTIFIER_PRIORITY, 1, + msti_bridge_identifier_priority); + proto_tree_add_uint(msti_tree, hf_bpdu_msti_port_identifier_priority, tvb, + offset+MSTI_PORT_IDENTIFIER_PRIORITY, 1, + msti_port_identifier_priority); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_remaining_hops, tvb, + offset + MSTI_REMAINING_HOPS, 1, ENC_BIG_ENDIAN); + + msti_length_remaining -= MSTI_MESSAGE_SIZE; + offset += MSTI_MESSAGE_SIZE; + break; + + case MSTI_FORMAT_ALTERNATIVE: + msti_regional_root_mstid = tvb_get_guint8(tvb, offset+ ALT_MSTI_REGIONAL_ROOT); + msti_regional_root_priority = (msti_regional_root_mstid &0xf0) << 8; + msti_regional_root_mstid = ((msti_regional_root_mstid & 0x0f) << 8) + + tvb_get_guint8(tvb, offset+ ALT_MSTI_REGIONAL_ROOT+1); + msti_regional_root_mac_str = tvb_ether_to_str(pinfo->pool, tvb, offset+ ALT_MSTI_REGIONAL_ROOT + 2); + + msti_tree = proto_tree_add_subtree_format(mstp_tree, tvb, offset, 16, ett_msti, NULL, + "MSTID %d, Regional Root Identifier %d / %s", + msti_regional_root_mstid, + msti_regional_root_priority, + msti_regional_root_mac_str); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_id, tvb, offset+ALT_MSTI_MSTID, 2, ENC_BIG_ENDIAN); + + /* flags */ + proto_tree_add_bitmask_with_flags(msti_tree, tvb, offset+ALT_MSTI_FLAGS, hf_bpdu_msti_flags, ett_bpdu_flags, rst_flags, ENC_NA, BMT_NO_FALSE|BMT_NO_TFS); + + /* pri, MSTID, Regional root */ + proto_tree_add_item(msti_tree, hf_bpdu_mst_priority, tvb, offset + ALT_MSTI_REGIONAL_ROOT, 1, ENC_BIG_ENDIAN); + proto_tree_add_item(msti_tree, hf_bpdu_msti_regional_root_id, tvb, offset + ALT_MSTI_REGIONAL_ROOT, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(msti_tree, hf_bpdu_msti_regional_root_mac, tvb, + offset + ALT_MSTI_REGIONAL_ROOT + 2, 6, ENC_NA); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_internal_root_path_cost, tvb, + offset+ALT_MSTI_INTERNAL_ROOT_PATH_COST, 4, ENC_BIG_ENDIAN); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_bridge_id, tvb, offset + ALT_MSTI_BRIDGE_IDENTIFIER, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(msti_tree, hf_bpdu_msti_bridge_id_priority, tvb, offset + ALT_MSTI_BRIDGE_IDENTIFIER, 2, ENC_BIG_ENDIAN); + proto_tree_add_item(msti_tree, hf_bpdu_msti_bridge_id_mac, tvb, + offset + ALT_MSTI_BRIDGE_IDENTIFIER + 2, 6, ENC_NA); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_port_id, tvb, offset+ALT_MSTI_PORT_IDENTIFIER, 2, ENC_BIG_ENDIAN); + + proto_tree_add_item(msti_tree, hf_bpdu_msti_remaining_hops, tvb, + offset + ALT_MSTI_REMAINING_HOPS, 1, ENC_BIG_ENDIAN); + + msti_length_remaining -= ALT_MSTI_MESSAGE_SIZE; + offset += ALT_MSTI_MESSAGE_SIZE; + break; + } + } + + if (protocol_version_identifier >= 4 && version_1_length == 0 + && tvb_reported_length(tvb) >= 106) { + /* + * OK, it passes the "Protocol Identifier is 0000 0000 + * 0000 0000", "Protocol Version Identifier is 4 or + * greater", "BPDU Type is 0000 0010", "contains 106 or + * more octets", and "a Version 1 Length of 0" tests. + */ + bpdu_version_4_length = BPDU_MSTI + total_msti_length; + version_4_length = tvb_get_ntohs(tvb, bpdu_version_4_length); + + proto_tree_add_uint(bpdu_tree, hf_bpdu_version_4_length, tvb, + bpdu_version_4_length, 2, version_4_length); + + /* version 4 length is 55 or more. + */ + if (version_4_length >= 53) { + static int * const agreements[] = { + &hf_bpdu_flags_agree_num, + &hf_bpdu_flags_dagree_num, + &hf_bpdu_flags_agree_valid, + &hf_bpdu_flags_restricted_role, + NULL + }; + + spt_tree = proto_tree_add_subtree(bpdu_tree, tvb, bpdu_version_4_length, -1, + ett_spt, NULL, "SPT Extension"); + + spt_offset = (bpdu_version_4_length + 2); + + /* Aux MCID: */ + + aux_mcid_tree = proto_tree_add_subtree(spt_tree, tvb, spt_offset, + MCID_LEN, ett_aux_mcid, NULL, "MCID Data"); + + proto_tree_add_item(aux_mcid_tree, + hf_bpdu_spt_config_format_selector, tvb, spt_offset, 1, + ENC_BIG_ENDIAN); + proto_tree_add_item(aux_mcid_tree, hf_bpdu_spt_config_name, tvb, + spt_offset + 1, 32, ENC_ASCII | ENC_NA); + + proto_tree_add_item(aux_mcid_tree, + hf_bpdu_spt_config_revision_level, tvb, spt_offset + 33, + 2, ENC_BIG_ENDIAN); + proto_tree_add_item(aux_mcid_tree, hf_bpdu_spt_config_digest, + tvb, spt_offset + 35, 16, ENC_NA); + spt_offset += MCID_LEN; + + /* Agreement Data */ + agreement_tree = proto_tree_add_subtree(spt_tree, tvb, spt_offset, + -1, ett_agreement, &agreement_item, "Agreement Data"); + + spt_agree_data = tvb_get_guint8(tvb, spt_offset); + + sep = initial_sep; + proto_item_append_text(agreement_item, "%sAN: %d", sep, (spt_agree_data & 0x03)); + + proto_tree_add_bitmask_list_value(agreement_tree, tvb, spt_offset, 1, agreements, spt_agree_data); + sep = cont_sep; + + proto_item_append_text(agreement_item, "%sDAN: %d", sep, ((spt_agree_data & 0x0C) >> 2)); + + if (sep != initial_sep) { + proto_item_append_text(agreement_item, ")"); + } + spt_offset += 2; + + proto_tree_add_item(agreement_tree, hf_bpdu_agreement_digest_format_id, tvb, spt_offset, 1, ENC_NA); + proto_tree_add_item(agreement_tree, hf_bpdu_agreement_digest_format_capabilities, tvb, spt_offset, 1, ENC_NA); + spt_offset += 1; + + proto_tree_add_item(agreement_tree, hf_bpdu_agreement_digest_convention_id, tvb, spt_offset, 1, ENC_NA); + proto_tree_add_item(agreement_tree, hf_bpdu_agreement_digest_convention_capabilities, tvb, spt_offset, 1, ENC_NA); + spt_offset += 1; + + proto_tree_add_item(agreement_tree, hf_bpdu_agreement_digest_edge_count, tvb, spt_offset, 2, ENC_BIG_ENDIAN); + spt_offset += 10; + + proto_tree_add_item(agreement_tree, hf_bpdu_spt_agreement_digest, + tvb, spt_offset, 20, ENC_NA); + /*spt_offset += 20;*/ + + if (protocol_version_identifier == 4) { + set_actual_length(tvb, (bpdu_version_4_length + version_4_length + 2)); + } + } + } + } else { /* It is RSTP BPDU and may still be Rapid PVST+ */ + if (is_bpdu_pvst) + dissect_bpdu_pvst_tlv(pinfo, bpdu_tree, tvb); + } +} + +static int +dissect_bpdu_cisco(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) +{ + dissect_bpdu(tvb, pinfo, tree, TRUE); + return tvb_captured_length(tvb); +} + +static int +dissect_bpdu_generic(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_) +{ + dissect_bpdu(tvb, pinfo, tree, FALSE); + return tvb_captured_length(tvb); +} + +void +proto_register_bpdu(void) +{ + + static hf_register_info hf[] = { + { &hf_bpdu_proto_id, + { "Protocol Identifier", "stp.protocol", + FT_UINT16, BASE_HEX, VALS(protocol_id_vals), 0x0, + NULL, HFILL }}, + { &hf_bpdu_version_id, + { "Protocol Version Identifier", "stp.version", + FT_UINT8, BASE_DEC, VALS(version_id_vals), 0x0, + NULL, HFILL }}, + { &hf_bpdu_type, + { "BPDU Type", "stp.type", + FT_UINT8, BASE_HEX, VALS(bpdu_type_vals), 0x0, + NULL, HFILL }}, + { &hf_bpdu_flags, + { "BPDU flags", "stp.flags", + FT_UINT8, BASE_HEX, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_flags_tcack, + { "Topology Change Acknowledgment", "stp.flags.tcack", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), BPDU_FLAGS_TCACK, + NULL, HFILL }}, + { &hf_bpdu_flags_agreement, + { "Agreement", "stp.flags.agreement", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), BPDU_FLAGS_AGREEMENT, + NULL, HFILL }}, + { &hf_bpdu_flags_forwarding, + { "Forwarding", "stp.flags.forwarding", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), BPDU_FLAGS_FORWARDING, + NULL, HFILL }}, + { &hf_bpdu_flags_learning, + { "Learning", "stp.flags.learning", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), BPDU_FLAGS_LEARNING, + NULL, HFILL }}, + { &hf_bpdu_flags_port_role, + { "Port Role", "stp.flags.port_role", + FT_UINT8, BASE_DEC, VALS(role_vals), BPDU_FLAGS_PORT_ROLE_MASK, + NULL, HFILL }}, + { &hf_bpdu_flags_proposal, + { "Proposal", "stp.flags.proposal", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), BPDU_FLAGS_PROPOSAL, + NULL, HFILL }}, + { &hf_bpdu_flags_tc, + { "Topology Change", "stp.flags.tc", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), BPDU_FLAGS_TC, + NULL, HFILL }}, + { &hf_bpdu_root_prio, + { "Root Bridge Priority", "stp.root.prio", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_root_sys_id_ext, + { "Root Bridge System ID Extension", "stp.root.ext", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_root_mac, + { "Root Bridge System ID", "stp.root.hw", + FT_ETHER, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_root_cost, + { "Root Path Cost", "stp.root.cost", + FT_UINT32, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_bridge_prio, + { "Bridge Priority", "stp.bridge.prio", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_bridge_sys_id_ext, + { "Bridge System ID Extension", "stp.bridge.ext", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_bridge_mac, + { "Bridge System ID", "stp.bridge.hw", + FT_ETHER, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_port_id, + { "Port identifier", "stp.port", + FT_UINT16, BASE_HEX, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msg_age, + { "Message Age", "stp.msg_age", + FT_DOUBLE, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_max_age, + { "Max Age", "stp.max_age", + FT_DOUBLE, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_hello_time, + { "Hello Time", "stp.hello", + FT_DOUBLE, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_forward_delay, + { "Forward Delay", "stp.forward", + FT_DOUBLE, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_version_1_length, + { "Version 1 Length", "stp.version_1_length", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_pvst_tlvtype, + { "Type", "stp.pvst.tlvtype", + FT_UINT16, BASE_HEX, VALS(bpdu_pvst_tlv_vals), 0x0, + NULL, HFILL }}, + { &hf_bpdu_pvst_tlvlength, + { "Length", "stp.pvst.tlvlen", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_pvst_tlv_origvlan, + { "Originating VLAN", "stp.pvst.origvlan", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_pvst_tlvvalue, + { "Value", "stp.pvst.tlvval", + FT_BYTES, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_version_3_length, + { "Version 3 Length", "mstp.version_3_length", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_mst_config_format_selector, + { "MST Config ID format selector", "mstp.config_format_selector", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_mst_config_name, + { "MST Config name", "mstp.config_name", + FT_STRINGZPAD, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_mst_config_revision_level, + { "MST Config revision", "mstp.config_revision_level", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_mst_config_digest, + { "MST Config digest", "mstp.config_digest", + FT_BYTES, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_cist_internal_root_path_cost, + { "CIST Internal Root Path Cost", "mstp.cist_internal_root_path_cost", + FT_UINT32, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_cist_bridge_prio, + { "CIST Bridge Priority", "mstp.cist_bridge.prio", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_cist_bridge_sys_id_ext, + { "CIST Bridge Identifier System ID Extension", "mstp.cist_bridge.ext", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_cist_bridge_mac, + { "CIST Bridge Identifier System ID", "mstp.cist_bridge.hw", + FT_ETHER, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_cist_remaining_hops, + { "CIST Remaining hops", "mstp.cist_remaining_hops", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_flags, + { "MSTI flags", "mstp.msti.flags", + FT_UINT8, BASE_HEX, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_mst_priority, + { "Priority", "mstp.msti.priority", + FT_UINT8, BASE_HEX, NULL, 0xF0, + NULL, HFILL }}, + { &hf_bpdu_msti_id_FFF, + { "MSTID", "mstp.msti.msti_id", + FT_UINT16, BASE_DEC, NULL, 0x0FFF, + NULL, HFILL }}, + { &hf_bpdu_msti_id, + { "MSTID", "mstp.msti.msti_id", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_regional_root_id, + { "MSTI Regional Root Identifier", "mstp.msti.regional_root_id", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_regional_root_mac, + { "Regional Root", "mstp.msti.root.hw", + FT_ETHER, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_internal_root_path_cost, + { "Internal root path cost", "mstp.msti.root_cost", + FT_UINT32, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_bridge_id, + { "MSTI Bridge Identifier", "mstp.msti.bridge_id", + FT_UINT16, BASE_DEC, NULL, 0x0FFF, + NULL, HFILL }}, + { &hf_bpdu_msti_bridge_id_priority, + { "MSTI Bridge Priority", "mstp.msti.bridge_id_priority", + FT_UINT16, BASE_DEC, NULL, 0xF000, + NULL, HFILL }}, + { &hf_bpdu_msti_bridge_id_mac, + { "MSTI Bridge MAC", "mstp.msti.bridge_id_mac", + FT_ETHER, BASE_NONE, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_bridge_identifier_priority, + { "Bridge Identifier Priority", "mstp.msti.bridge_priority", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_port_identifier_priority, + { "Port identifier priority", "mstp.msti.port_priority", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_port_id, + { "Port identifier", "mstp.msti.port", + FT_UINT16, BASE_HEX, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_msti_remaining_hops, + { "Remaining hops", "mstp.msti.remaining_hops", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_version_4_length, + { "Version 4 Length", "mstp.version_4_length", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_spt_config_format_selector, + { "SPT Config ID format selector", "mstp.config_format_selector", + FT_UINT8, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + { &hf_bpdu_spt_config_name, + {"SPT Config name", "mstp.config_name", + FT_STRINGZPAD, BASE_NONE, NULL, 0x0, + NULL, HFILL } }, + { &hf_bpdu_spt_config_revision_level, + { "SPT Config revision", "mstp.config_revision_level", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL } }, + { &hf_bpdu_spt_config_digest, + { "SPT Config digest", "mstp.config_digest", + FT_BYTES, BASE_NONE, NULL, 0x0, + NULL, HFILL } }, + { &hf_bpdu_flags_agree_num, + { "Agreement Number", "mstp.agree_flags.agreement_num", + FT_UINT8, BASE_DEC, NULL, 0x03, + NULL, HFILL } }, + { &hf_bpdu_flags_dagree_num, + { "Disagreement Number", "mstp.agree_flags.dagreement_num", + FT_UINT8, BASE_DEC, NULL, 0x0C, + NULL, HFILL } }, + { &hf_bpdu_flags_agree_valid, + { "Agreement Valid Flag", "mstp.agree_flags.agreement_valid", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), 0x10, + NULL, HFILL } }, + { &hf_bpdu_flags_restricted_role, + { "Restricted Role", "mstp.agree_flags.rest_role", + FT_BOOLEAN, 8, TFS(&tfs_yes_no), 0x20, + NULL, HFILL } }, + { &hf_bpdu_spt_agreement_digest, + { "Agreement Digest", "mstp.agreement_digest", + FT_BYTES, BASE_NONE, NULL, 0x0, + NULL, HFILL } }, + { &hf_bpdu_agreement_digest_format_id, + { "Agreement Digest Format Id", "bpdu.agreement_digest_format_id", + FT_UINT8, BASE_DEC, NULL, 0xF0, + NULL, HFILL }}, + { &hf_bpdu_agreement_digest_format_capabilities, + { "Agreement Digest Format Capabilities", "bpdu.agreement_digest_format_capabilities", + FT_UINT8, BASE_DEC, NULL, 0x0F, + NULL, HFILL }}, + { &hf_bpdu_agreement_digest_convention_id, + { "Agreement Digest Convention Id", "bpdu.agreement_digest_convention_id", + FT_UINT8, BASE_DEC, NULL, 0xF0, + NULL, HFILL }}, + { &hf_bpdu_agreement_digest_convention_capabilities, + { "Agreement Digest Convention Capabilities", "bpdu.agreement_digest_convention_capabilities", + FT_UINT8, BASE_DEC, NULL, 0x0F, + NULL, HFILL }}, + { &hf_bpdu_agreement_digest_edge_count, + { "Agreement Digest Edge Count", "bpdu.agreement_digest_edge_count", + FT_UINT16, BASE_DEC, NULL, 0x0, + NULL, HFILL }}, + }; + static gint *ett[] = { + &ett_bpdu, + &ett_bpdu_flags, + &ett_root_id, + &ett_bridge_id, + &ett_mstp, + &ett_msti, + &ett_cist_bridge_id, + &ett_spt, + &ett_aux_mcid, + &ett_agreement, + &ett_bpdu_pvst_tlv + }; + + static ei_register_info ei[] = { + { &ei_pvst_tlv_length_invalid, + { "stp.pvst.tlvlen.invalid", PI_MALFORMED, PI_ERROR, + "Indicated length is not valid for this record type", EXPFILL }}, + + { &ei_pvst_tlv_origvlan_missing, + { "stp.pvst.origvlan.missing", PI_MALFORMED, PI_ERROR, + "Originating (PVID) VLAN TLV is missing or corrupt", EXPFILL }}, + + { &ei_pvst_tlv_truncated, + { "stp.pvst.tlv.truncated", PI_MALFORMED, PI_ERROR, + "TLV record is truncated prematurely", EXPFILL }}, + + { &ei_pvst_tlv_unknown, + { "stp.pvst.tlv.unknown", PI_UNDECODED, PI_COMMENT, + "TLV type is unknown", EXPFILL }}, + + { &ei_bpdu_version_support, + { "bpdu.version_support", PI_PROTOCOL, PI_WARN, + "This version of Wireshark only knows about versions 0, 2, 3 & 4", EXPFILL }}, + + { &ei_bpdu_type, + { "stp.type.unknown", PI_PROTOCOL, PI_WARN, + "Unknown BPDU type data", EXPFILL }}, + }; + + module_t *bpdu_module; + expert_module_t *expert_bpdu; + + proto_bpdu = proto_register_protocol("Spanning Tree Protocol", "STP", "stp"); + proto_register_field_array(proto_bpdu, hf, array_length(hf)); + proto_register_subtree_array(ett, array_length(ett)); + + bpdu_handle = register_dissector("bpdu", dissect_bpdu_generic, proto_bpdu); + bpdu_cisco_handle = register_dissector("bpdu_cisco", dissect_bpdu_cisco, proto_bpdu); + + expert_bpdu = expert_register_protocol(proto_bpdu); + expert_register_field_array(expert_bpdu, ei, array_length(ei)); + + bpdu_module = prefs_register_protocol(proto_bpdu, NULL); + prefs_register_bool_preference(bpdu_module, "use_system_id_extension", + "Use 802.1t System ID Extensions", + "Whether the BPDU dissector should use 802.1t System ID Extensions when dissecting the Bridge Identifier", + &bpdu_use_system_id_extensions); +} + +void +proto_reg_handoff_bpdu(void) +{ + /* + * Get handle for the GVRP dissector. + */ + gvrp_handle = find_dissector("gvrp"); + + /* + * Get handle for the GMRP dissector. + */ + gmrp_handle = find_dissector_add_dependency("gmrp", proto_bpdu); + + dissector_add_uint("llc.dsap", SAP_BPDU, bpdu_handle); + dissector_add_uint("chdlc.protocol", CHDLCTYPE_BPDU, bpdu_handle); + dissector_add_uint("ethertype", ETHERTYPE_STP, bpdu_handle); + dissector_add_uint("llc.cisco_pid", CISCO_PID_RLQ_REQ, bpdu_handle); /* Cisco's RLQ is just plain STP */ + dissector_add_uint("llc.cisco_pid", CISCO_PID_RLQ_RESP, bpdu_handle); /* Cisco's RLQ is just plain STP */ + dissector_add_uint("llc.cisco_pid", CISCO_PID_VLAN_BRIDGE, bpdu_handle); /* Cisco's VLAN-bridge STP is just plain STP */ + dissector_add_uint("llc.cisco_pid", CISCO_PID_PVSTPP, bpdu_cisco_handle); /* Handle Cisco's (R)PVST+ TLV extensions */ +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local Variables: + * c-basic-offset: 2 + * tab-width: 8 + * indent-tabs-mode: nil + * End: + * + * ex: set shiftwidth=2 tabstop=8 expandtab: + * :indentSize=2:tabSize=8:noTabs=true: + */ |