Local changes: - Update some local modifications to fix build - Synch config.h with upstream as much as possible Changelog: https://git.tcpdump.org/tcpdump/blob/55bc126b0216cfe409b8d6bd378f65679d136ddf:/CHANGES Reviewed by: emaste Obtained from: https://www.tcpdump.org/release/tcpdump-4.99.4.tar.gz Sponsored by: The FreeBSD Foundation
472 lines
16 KiB
C
472 lines
16 KiB
C
/*
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* Copyright (c) 2000 Lennert Buytenhek
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*
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* This software may be distributed either under the terms of the
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* BSD-style license that accompanies tcpdump or the GNU General
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* Public License
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*
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* Contributed by Lennert Buytenhek <buytenh@gnu.org>
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*/
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/* \summary: IEEE 802.1d Spanning Tree Protocol (STP) printer */
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#ifdef HAVE_CONFIG_H
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#include <config.h>
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#endif
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#include "netdissect-stdinc.h"
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#include <stdio.h>
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#include "netdissect.h"
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#include "extract.h"
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#define RSTP_EXTRACT_PORT_ROLE(x) (((x)&0x0C)>>2)
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/* STP timers are expressed in multiples of 1/256th second */
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#define STP_TIME_BASE 256
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#define STP_BPDU_MSTP_MIN_LEN 102
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struct stp_bpdu_ {
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nd_uint16_t protocol_id;
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nd_uint8_t protocol_version;
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nd_uint8_t bpdu_type;
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nd_uint8_t flags;
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nd_byte root_id[8];
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nd_uint32_t root_path_cost;
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nd_byte bridge_id[8];
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nd_uint16_t port_id;
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nd_uint16_t message_age;
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nd_uint16_t max_age;
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nd_uint16_t hello_time;
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nd_uint16_t forward_delay;
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nd_uint8_t v1_length;
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};
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#define STP_PROTO_REGULAR 0x00
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#define STP_PROTO_RAPID 0x02
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#define STP_PROTO_MSTP 0x03
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#define STP_PROTO_SPB 0x04
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static const struct tok stp_proto_values[] = {
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{ STP_PROTO_REGULAR, "802.1d" },
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{ STP_PROTO_RAPID, "802.1w" },
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{ STP_PROTO_MSTP, "802.1s" },
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{ STP_PROTO_SPB, "802.1aq" },
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{ 0, NULL}
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};
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#define STP_BPDU_TYPE_CONFIG 0x00
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#define STP_BPDU_TYPE_RSTP 0x02
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#define STP_BPDU_TYPE_TOPO_CHANGE 0x80
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static const struct tok stp_bpdu_flag_values[] = {
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{ 0x01, "Topology change" },
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{ 0x02, "Proposal" },
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{ 0x10, "Learn" },
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{ 0x20, "Forward" },
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{ 0x40, "Agreement" },
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{ 0x80, "Topology change ACK" },
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{ 0, NULL}
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};
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static const struct tok stp_bpdu_type_values[] = {
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{ STP_BPDU_TYPE_CONFIG, "Config" },
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{ STP_BPDU_TYPE_RSTP, "Rapid STP" },
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{ STP_BPDU_TYPE_TOPO_CHANGE, "Topology Change" },
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{ 0, NULL}
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};
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static const struct tok rstp_obj_port_role_values[] = {
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{ 0x00, "Unknown" },
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{ 0x01, "Alternate" },
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{ 0x02, "Root" },
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{ 0x03, "Designated" },
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{ 0, NULL}
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};
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static char *
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stp_print_bridge_id(netdissect_options *ndo, const u_char *p)
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{
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static char bridge_id_str[sizeof("pppp.aa:bb:cc:dd:ee:ff")];
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snprintf(bridge_id_str, sizeof(bridge_id_str),
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"%.2x%.2x.%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
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GET_U_1(p), GET_U_1(p + 1), GET_U_1(p + 2),
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GET_U_1(p + 3), GET_U_1(p + 4), GET_U_1(p + 5),
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GET_U_1(p + 6), GET_U_1(p + 7));
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return bridge_id_str;
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}
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static void
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stp_print_config_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
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u_int length)
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{
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uint8_t bpdu_flags;
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bpdu_flags = GET_U_1(stp_bpdu->flags);
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ND_PRINT(", Flags [%s]",
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bittok2str(stp_bpdu_flag_values, "none", bpdu_flags));
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ND_PRINT(", bridge-id %s.%04x, length %u",
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stp_print_bridge_id(ndo, stp_bpdu->bridge_id),
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GET_BE_U_2(stp_bpdu->port_id), length);
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/* in non-verbose mode just print the bridge-id */
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if (!ndo->ndo_vflag) {
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return;
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}
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ND_PRINT("\n\tmessage-age %.2fs, max-age %.2fs"
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", hello-time %.2fs, forwarding-delay %.2fs",
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(float) GET_BE_U_2(stp_bpdu->message_age) / STP_TIME_BASE,
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(float) GET_BE_U_2(stp_bpdu->max_age) / STP_TIME_BASE,
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(float) GET_BE_U_2(stp_bpdu->hello_time) / STP_TIME_BASE,
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(float) GET_BE_U_2(stp_bpdu->forward_delay) / STP_TIME_BASE);
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ND_PRINT("\n\troot-id %s, root-pathcost %u",
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stp_print_bridge_id(ndo, stp_bpdu->root_id),
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GET_BE_U_4(stp_bpdu->root_path_cost));
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/* Port role is only valid for 802.1w */
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if (GET_U_1(stp_bpdu->protocol_version) == STP_PROTO_RAPID) {
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ND_PRINT(", port-role %s",
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tok2str(rstp_obj_port_role_values, "Unknown",
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RSTP_EXTRACT_PORT_ROLE(bpdu_flags)));
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}
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}
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/*
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* MSTP packet format
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* Ref. IEEE 802.1Q 2003 Ed. Section 14
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*
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* MSTP BPDU
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*
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* 2 - bytes Protocol Id
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* 1 - byte Protocol Ver.
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* 1 - byte BPDU type
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* 1 - byte Flags
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* 8 - bytes CIST Root Identifier
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* 4 - bytes CIST External Path Cost
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* 8 - bytes CIST Regional Root Identifier
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* 2 - bytes CIST Port Identifier
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* 2 - bytes Message Age
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* 2 - bytes Max age
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* 2 - bytes Hello Time
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* 2 - bytes Forward delay
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* 1 - byte Version 1 length. Must be 0
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* 2 - bytes Version 3 length
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* 1 - byte Config Identifier
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* 32 - bytes Config Name
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* 2 - bytes Revision level
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* 16 - bytes Config Digest [MD5]
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* 4 - bytes CIST Internal Root Path Cost
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* 8 - bytes CIST Bridge Identifier
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* 1 - byte CIST Remaining Hops
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* 16 - bytes MSTI information [Max 64 MSTI, each 16 bytes]
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*
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*
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* SPB BPDU
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* Ref. IEEE 802.1aq. Section 14
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*
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* 2 - bytes Version 4 length
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* 1 - byte Aux Config Identifier
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* 32 - bytes Aux Config Name
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* 2 - bytes Aux Revision level
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* 16 - bytes Aux Config Digest [MD5]
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* 1 - byte (1 - 2) Agreement Number
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* (3 - 4) Discarded Agreement Number
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* (5) Agreement Valid Flag
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* (6) Restricted Role Flag
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* (7 - 8) Unused sent zero
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* 1 - byte Unused
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* 1 - byte (1 - 4) Agreement Digest Format Identifier
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* (5 - 8) Agreement Digest Format Capabilities
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* 1 - byte (1 - 4) Agreement Digest Convention Identifier
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* (5 - 8) Agreement Digest Convention Capabilities
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* 2 - bytes Agreement Digest Edge Count
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* 8 - byte Reserved Set
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* 20 - bytes Computed Topology Digest
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*
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*
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* MSTI Payload
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*
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* 1 - byte MSTI flag
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* 8 - bytes MSTI Regional Root Identifier
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* 4 - bytes MSTI Regional Path Cost
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* 1 - byte MSTI Bridge Priority
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* 1 - byte MSTI Port Priority
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* 1 - byte MSTI Remaining Hops
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*
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*/
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#define MST_BPDU_MSTI_LENGTH 16
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#define MST_BPDU_CONFIG_INFO_LENGTH 64
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/* Offsets of fields from the beginning for the packet */
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#define MST_BPDU_VER3_LEN_OFFSET 36
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#define MST_BPDU_CONFIG_NAME_OFFSET 39
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#define MST_BPDU_CONFIG_DIGEST_OFFSET 73
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#define MST_BPDU_CIST_INT_PATH_COST_OFFSET 89
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#define MST_BPDU_CIST_BRIDGE_ID_OFFSET 93
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#define MST_BPDU_CIST_REMAIN_HOPS_OFFSET 101
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#define MST_BPDU_MSTI_OFFSET 102
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/* Offsets within an MSTI */
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#define MST_BPDU_MSTI_ROOT_PRIO_OFFSET 1
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#define MST_BPDU_MSTI_ROOT_PATH_COST_OFFSET 9
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#define MST_BPDU_MSTI_BRIDGE_PRIO_OFFSET 13
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#define MST_BPDU_MSTI_PORT_PRIO_OFFSET 14
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#define MST_BPDU_MSTI_REMAIN_HOPS_OFFSET 15
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#define SPB_BPDU_MIN_LEN 87
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#define SPB_BPDU_CONFIG_NAME_OFFSET 3
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#define SPB_BPDU_CONFIG_REV_OFFSET SPB_BPDU_CONFIG_NAME_OFFSET + 32
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#define SPB_BPDU_CONFIG_DIGEST_OFFSET SPB_BPDU_CONFIG_REV_OFFSET + 2
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#define SPB_BPDU_AGREEMENT_OFFSET SPB_BPDU_CONFIG_DIGEST_OFFSET + 16
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#define SPB_BPDU_AGREEMENT_UNUSED_OFFSET SPB_BPDU_AGREEMENT_OFFSET + 1
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#define SPB_BPDU_AGREEMENT_FORMAT_OFFSET SPB_BPDU_AGREEMENT_UNUSED_OFFSET + 1
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#define SPB_BPDU_AGREEMENT_CON_OFFSET SPB_BPDU_AGREEMENT_FORMAT_OFFSET + 1
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#define SPB_BPDU_AGREEMENT_EDGE_OFFSET SPB_BPDU_AGREEMENT_CON_OFFSET + 1
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#define SPB_BPDU_AGREEMENT_RES1_OFFSET SPB_BPDU_AGREEMENT_EDGE_OFFSET + 2
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#define SPB_BPDU_AGREEMENT_RES2_OFFSET SPB_BPDU_AGREEMENT_RES1_OFFSET + 4
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#define SPB_BPDU_AGREEMENT_DIGEST_OFFSET SPB_BPDU_AGREEMENT_RES2_OFFSET + 4
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static void
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stp_print_mstp_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
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u_int length)
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{
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const u_char *ptr;
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uint8_t bpdu_flags;
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uint16_t v3len;
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uint16_t len;
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uint16_t msti;
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u_int offset;
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ptr = (const u_char *)stp_bpdu;
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bpdu_flags = GET_U_1(stp_bpdu->flags);
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ND_PRINT(", CIST Flags [%s], length %u",
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bittok2str(stp_bpdu_flag_values, "none", bpdu_flags), length);
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/*
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* in non-verbose mode just print the flags.
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*/
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if (!ndo->ndo_vflag) {
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return;
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}
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ND_PRINT("\n\tport-role %s, ",
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tok2str(rstp_obj_port_role_values, "Unknown",
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RSTP_EXTRACT_PORT_ROLE(bpdu_flags)));
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ND_PRINT("CIST root-id %s, CIST ext-pathcost %u",
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stp_print_bridge_id(ndo, stp_bpdu->root_id),
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GET_BE_U_4(stp_bpdu->root_path_cost));
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ND_PRINT("\n\tCIST regional-root-id %s, ",
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stp_print_bridge_id(ndo, stp_bpdu->bridge_id));
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ND_PRINT("CIST port-id %04x,", GET_BE_U_2(stp_bpdu->port_id));
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ND_PRINT("\n\tmessage-age %.2fs, max-age %.2fs"
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", hello-time %.2fs, forwarding-delay %.2fs",
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(float) GET_BE_U_2(stp_bpdu->message_age) / STP_TIME_BASE,
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(float) GET_BE_U_2(stp_bpdu->max_age) / STP_TIME_BASE,
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(float) GET_BE_U_2(stp_bpdu->hello_time) / STP_TIME_BASE,
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(float) GET_BE_U_2(stp_bpdu->forward_delay) / STP_TIME_BASE);
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ND_PRINT("\n\tv3len %u, ", GET_BE_U_2(ptr + MST_BPDU_VER3_LEN_OFFSET));
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ND_PRINT("MCID Name ");
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nd_printjnp(ndo, ptr + MST_BPDU_CONFIG_NAME_OFFSET, 32);
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ND_PRINT(", rev %u,"
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"\n\t\tdigest %08x%08x%08x%08x, ",
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GET_BE_U_2(ptr + MST_BPDU_CONFIG_NAME_OFFSET + 32),
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GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET),
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GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 4),
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GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 8),
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GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12));
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ND_PRINT("CIST int-root-pathcost %u,",
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GET_BE_U_4(ptr + MST_BPDU_CIST_INT_PATH_COST_OFFSET));
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ND_PRINT("\n\tCIST bridge-id %s, ",
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stp_print_bridge_id(ndo, ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET));
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ND_PRINT("CIST remaining-hops %u",
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GET_U_1(ptr + MST_BPDU_CIST_REMAIN_HOPS_OFFSET));
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/* Dump all MSTI's */
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v3len = GET_BE_U_2(ptr + MST_BPDU_VER3_LEN_OFFSET);
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if (v3len > MST_BPDU_CONFIG_INFO_LENGTH) {
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len = v3len - MST_BPDU_CONFIG_INFO_LENGTH;
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offset = MST_BPDU_MSTI_OFFSET;
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while (len >= MST_BPDU_MSTI_LENGTH) {
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msti = GET_BE_U_2(ptr + offset + MST_BPDU_MSTI_ROOT_PRIO_OFFSET);
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msti = msti & 0x0FFF;
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ND_PRINT("\n\tMSTI %u, Flags [%s], port-role %s",
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msti,
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bittok2str(stp_bpdu_flag_values, "none", GET_U_1(ptr + offset)),
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tok2str(rstp_obj_port_role_values, "Unknown",
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RSTP_EXTRACT_PORT_ROLE(GET_U_1(ptr + offset))));
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ND_PRINT("\n\t\tMSTI regional-root-id %s, pathcost %u",
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stp_print_bridge_id(ndo, ptr + offset +
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MST_BPDU_MSTI_ROOT_PRIO_OFFSET),
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GET_BE_U_4(ptr + offset + MST_BPDU_MSTI_ROOT_PATH_COST_OFFSET));
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ND_PRINT("\n\t\tMSTI bridge-prio %u, port-prio %u, hops %u",
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GET_U_1(ptr + offset + MST_BPDU_MSTI_BRIDGE_PRIO_OFFSET) >> 4,
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GET_U_1(ptr + offset + MST_BPDU_MSTI_PORT_PRIO_OFFSET) >> 4,
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GET_U_1(ptr + offset + MST_BPDU_MSTI_REMAIN_HOPS_OFFSET));
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len -= MST_BPDU_MSTI_LENGTH;
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offset += MST_BPDU_MSTI_LENGTH;
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}
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}
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}
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static void
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stp_print_spb_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
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u_int offset)
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{
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const u_char *ptr;
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/*
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* in non-verbose mode don't print anything.
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*/
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if (!ndo->ndo_vflag) {
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return;
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}
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ptr = (const u_char *)stp_bpdu;
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ND_PRINT("\n\tv4len %u, ", GET_BE_U_2(ptr + offset));
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ND_PRINT("AUXMCID Name ");
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nd_printjnp(ndo, ptr + offset + SPB_BPDU_CONFIG_NAME_OFFSET, 32);
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ND_PRINT(", Rev %u,\n\t\tdigest %08x%08x%08x%08x",
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GET_BE_U_2(ptr + offset + SPB_BPDU_CONFIG_REV_OFFSET),
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GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET),
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GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 4),
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GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 8),
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GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 12));
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ND_PRINT("\n\tAgreement num %u, Discarded Agreement num %u, Agreement valid-"
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"flag %u,\n\tRestricted role-flag: %u, Format id %u cap %u, "
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"Convention id %u cap %u,\n\tEdge count %u, "
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"Agreement digest %08x%08x%08x%08x%08x",
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>6,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>4 & 0x3,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>3 & 0x1,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>2 & 0x1,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_FORMAT_OFFSET)>>4,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_FORMAT_OFFSET)&0x00ff,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_CON_OFFSET)>>4,
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GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_CON_OFFSET)&0x00ff,
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GET_BE_U_2(ptr + offset + SPB_BPDU_AGREEMENT_EDGE_OFFSET),
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GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET),
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GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 4),
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GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 8),
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GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 12),
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GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 16));
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}
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/*
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* Print 802.1d / 802.1w / 802.1q (mstp) / 802.1aq (spb) packets.
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*/
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void
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stp_print(netdissect_options *ndo, const u_char *p, u_int length)
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{
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const struct stp_bpdu_ *stp_bpdu;
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u_int protocol_version;
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u_int bpdu_type;
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u_int mstp_len;
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u_int spb_len;
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ndo->ndo_protocol = "stp";
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stp_bpdu = (const struct stp_bpdu_*)p;
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/* Minimum STP Frame size. */
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if (length < 4)
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goto invalid;
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if (GET_BE_U_2(stp_bpdu->protocol_id)) {
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ND_PRINT("unknown STP version, length %u", length);
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return;
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}
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protocol_version = GET_U_1(stp_bpdu->protocol_version);
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ND_PRINT("STP %s", tok2str(stp_proto_values, "Unknown STP protocol (0x%02x)",
|
|
protocol_version));
|
|
|
|
switch (protocol_version) {
|
|
case STP_PROTO_REGULAR:
|
|
case STP_PROTO_RAPID:
|
|
case STP_PROTO_MSTP:
|
|
case STP_PROTO_SPB:
|
|
break;
|
|
default:
|
|
return;
|
|
}
|
|
|
|
bpdu_type = GET_U_1(stp_bpdu->bpdu_type);
|
|
ND_PRINT(", %s", tok2str(stp_bpdu_type_values, "Unknown BPDU Type (0x%02x)",
|
|
bpdu_type));
|
|
|
|
switch (bpdu_type) {
|
|
case STP_BPDU_TYPE_CONFIG:
|
|
if (length < sizeof(struct stp_bpdu_) - 1) {
|
|
goto invalid;
|
|
}
|
|
stp_print_config_bpdu(ndo, stp_bpdu, length);
|
|
break;
|
|
|
|
case STP_BPDU_TYPE_RSTP:
|
|
if (protocol_version == STP_PROTO_RAPID) {
|
|
if (length < sizeof(struct stp_bpdu_)) {
|
|
goto invalid;
|
|
}
|
|
stp_print_config_bpdu(ndo, stp_bpdu, length);
|
|
} else if (protocol_version == STP_PROTO_MSTP ||
|
|
protocol_version == STP_PROTO_SPB) {
|
|
if (length < STP_BPDU_MSTP_MIN_LEN) {
|
|
goto invalid;
|
|
}
|
|
|
|
if (GET_U_1(stp_bpdu->v1_length) != 0) {
|
|
/* FIX ME: Emit a message here ? */
|
|
goto invalid;
|
|
}
|
|
|
|
/* Validate v3 length */
|
|
mstp_len = GET_BE_U_2(p + MST_BPDU_VER3_LEN_OFFSET);
|
|
mstp_len += 2; /* length encoding itself is 2 bytes */
|
|
if (length < (sizeof(struct stp_bpdu_) + mstp_len)) {
|
|
goto invalid;
|
|
}
|
|
stp_print_mstp_bpdu(ndo, stp_bpdu, length);
|
|
|
|
if (protocol_version == STP_PROTO_SPB)
|
|
{
|
|
/* Validate v4 length */
|
|
spb_len = GET_BE_U_2(p + MST_BPDU_VER3_LEN_OFFSET + mstp_len);
|
|
spb_len += 2;
|
|
if (length < (sizeof(struct stp_bpdu_) + mstp_len + spb_len) ||
|
|
spb_len < SPB_BPDU_MIN_LEN) {
|
|
goto invalid;
|
|
}
|
|
stp_print_spb_bpdu(ndo, stp_bpdu, (sizeof(struct stp_bpdu_) + mstp_len));
|
|
}
|
|
}
|
|
break;
|
|
|
|
case STP_BPDU_TYPE_TOPO_CHANGE:
|
|
/* always empty message - just break out */
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
return;
|
|
|
|
invalid:
|
|
nd_print_invalid(ndo);
|
|
}
|