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Add a test file for a previous fix
[tcpdump] / print-stp.c
1 /*
2 * Copyright (c) 2000 Lennert Buytenhek
3 *
4 * This software may be distributed either under the terms of the
5 * BSD-style license that accompanies tcpdump or the GNU General
6 * Public License
7 *
8 * Contributed by Lennert Buytenhek <buytenh@gnu.org>
9 */
10
11 /* \summary: IEEE 802.1d Spanning Tree Protocol (STP) printer */
12
13 #ifdef HAVE_CONFIG_H
14 #include "config.h"
15 #endif
16
17 #include <netdissect-stdinc.h>
18
19 #include <stdio.h>
20
21 #include "netdissect.h"
22 #include "extract.h"
23
24 #define RSTP_EXTRACT_PORT_ROLE(x) (((x)&0x0C)>>2)
25 /* STP timers are expressed in multiples of 1/256th second */
26 #define STP_TIME_BASE 256
27 #define STP_BPDU_MSTP_MIN_LEN 102
28
29 struct stp_bpdu_ {
30 uint8_t protocol_id[2];
31 uint8_t protocol_version;
32 uint8_t bpdu_type;
33 uint8_t flags;
34 uint8_t root_id[8];
35 uint8_t root_path_cost[4];
36 uint8_t bridge_id[8];
37 uint8_t port_id[2];
38 uint8_t message_age[2];
39 uint8_t max_age[2];
40 uint8_t hello_time[2];
41 uint8_t forward_delay[2];
42 uint8_t v1_length;
43 };
44
45 #define STP_PROTO_REGULAR 0x00
46 #define STP_PROTO_RAPID 0x02
47 #define STP_PROTO_MSTP 0x03
48 #define STP_PROTO_SPB 0x04
49
50 static const struct tok stp_proto_values[] = {
51 { STP_PROTO_REGULAR, "802.1d" },
52 { STP_PROTO_RAPID, "802.1w" },
53 { STP_PROTO_MSTP, "802.1s" },
54 { STP_PROTO_SPB, "802.1aq" },
55 { 0, NULL}
56 };
57
58 #define STP_BPDU_TYPE_CONFIG 0x00
59 #define STP_BPDU_TYPE_RSTP 0x02
60 #define STP_BPDU_TYPE_TOPO_CHANGE 0x80
61
62 static const struct tok stp_bpdu_flag_values[] = {
63 { 0x01, "Topology change" },
64 { 0x02, "Proposal" },
65 { 0x10, "Learn" },
66 { 0x20, "Forward" },
67 { 0x40, "Agreement" },
68 { 0x80, "Topology change ACK" },
69 { 0, NULL}
70 };
71
72 static const struct tok stp_bpdu_type_values[] = {
73 { STP_BPDU_TYPE_CONFIG, "Config" },
74 { STP_BPDU_TYPE_RSTP, "Rapid STP" },
75 { STP_BPDU_TYPE_TOPO_CHANGE, "Topology Change" },
76 { 0, NULL}
77 };
78
79 static const struct tok rstp_obj_port_role_values[] = {
80 { 0x00, "Unknown" },
81 { 0x01, "Alternate" },
82 { 0x02, "Root" },
83 { 0x03, "Designated" },
84 { 0, NULL}
85 };
86
87 #define ND_TCHECK_BRIDGE_ID(p) ND_TCHECK2(*(p), 8)
88
89 static char *
90 stp_print_bridge_id(const u_char *p)
91 {
92 static char bridge_id_str[sizeof("pppp.aa:bb:cc:dd:ee:ff")];
93
94 snprintf(bridge_id_str, sizeof(bridge_id_str),
95 "%.2x%.2x.%.2x:%.2x:%.2x:%.2x:%.2x:%.2x",
96 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);
97
98 return bridge_id_str;
99 }
100
101 static int
102 stp_print_config_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
103 u_int length)
104 {
105 ND_TCHECK(stp_bpdu->flags);
106 ND_PRINT((ndo, ", Flags [%s]",
107 bittok2str(stp_bpdu_flag_values, "none", stp_bpdu->flags)));
108
109 ND_TCHECK(stp_bpdu->port_id);
110 ND_PRINT((ndo, ", bridge-id %s.%04x, length %u",
111 stp_print_bridge_id((const u_char *)&stp_bpdu->bridge_id),
112 EXTRACT_16BITS(&stp_bpdu->port_id), length));
113
114 /* in non-verbose mode just print the bridge-id */
115 if (!ndo->ndo_vflag) {
116 return 1;
117 }
118
119 ND_TCHECK(stp_bpdu->forward_delay);
120 ND_PRINT((ndo, "\n\tmessage-age %.2fs, max-age %.2fs"
121 ", hello-time %.2fs, forwarding-delay %.2fs",
122 (float)EXTRACT_16BITS(&stp_bpdu->message_age) / STP_TIME_BASE,
123 (float)EXTRACT_16BITS(&stp_bpdu->max_age) / STP_TIME_BASE,
124 (float)EXTRACT_16BITS(&stp_bpdu->hello_time) / STP_TIME_BASE,
125 (float)EXTRACT_16BITS(&stp_bpdu->forward_delay) / STP_TIME_BASE));
126
127 ND_PRINT((ndo, "\n\troot-id %s, root-pathcost %u",
128 stp_print_bridge_id((const u_char *)&stp_bpdu->root_id),
129 EXTRACT_32BITS(&stp_bpdu->root_path_cost)));
130
131 /* Port role is only valid for 802.1w */
132 if (stp_bpdu->protocol_version == STP_PROTO_RAPID) {
133 ND_PRINT((ndo, ", port-role %s",
134 tok2str(rstp_obj_port_role_values, "Unknown",
135 RSTP_EXTRACT_PORT_ROLE(stp_bpdu->flags))));
136 }
137 return 1;
138
139 trunc:
140 return 0;
141 }
142
143 /*
144 * MSTP packet format
145 * Ref. IEEE 802.1Q 2003 Ed. Section 14
146 *
147 * MSTP BPDU
148 *
149 * 2 - bytes Protocol Id
150 * 1 - byte Protocol Ver.
151 * 1 - byte BPDU tye
152 * 1 - byte Flags
153 * 8 - bytes CIST Root Identifier
154 * 4 - bytes CIST External Path Cost
155 * 8 - bytes CIST Regional Root Identifier
156 * 2 - bytes CIST Port Identifier
157 * 2 - bytes Message Age
158 * 2 - bytes Max age
159 * 2 - bytes Hello Time
160 * 2 - bytes Forward delay
161 * 1 - byte Version 1 length. Must be 0
162 * 2 - bytes Version 3 length
163 * 1 - byte Config Identifier
164 * 32 - bytes Config Name
165 * 2 - bytes Revision level
166 * 16 - bytes Config Digest [MD5]
167 * 4 - bytes CIST Internal Root Path Cost
168 * 8 - bytes CIST Bridge Identifier
169 * 1 - byte CIST Remaining Hops
170 * 16 - bytes MSTI information [Max 64 MSTI, each 16 bytes]
171 *
172 *
173 * SPB BPDU
174 * Ref. IEEE 802.1aq. Section 14
175 *
176 * 2 - bytes Version 4 length
177 * 1 - byte Aux Config Identifier
178 * 32 - bytes Aux Config Name
179 * 2 - bytes Aux Revision level
180 * 16 - bytes Aux Config Digest [MD5]
181 * 1 - byte (1 - 2) Agreement Number
182 * (3 - 4) Discarded Agreement Number
183 * (5) Agreement Valid Flag
184 * (6) Restricted Role Flag
185 * (7 - 8) Unused sent zero
186 * 1 - byte Unused
187 * 1 - byte (1 - 4) Agreement Digest Format Identifier
188 * (5 - 8) Agreement Digest Format Capabilities
189 * 1 - byte (1 - 4) Agreement Digest Convention Identifier
190 * (5 - 8) Agreement Digest Convention Capabilities
191 * 2 - bytes Agreement Digest Edge Count
192 * 8 - byte Reserved Set
193 * 20 - bytes Computed Topology Digest
194 *
195 *
196 * MSTI Payload
197 *
198 * 1 - byte MSTI flag
199 * 8 - bytes MSTI Regional Root Identifier
200 * 4 - bytes MSTI Regional Path Cost
201 * 1 - byte MSTI Bridge Priority
202 * 1 - byte MSTI Port Priority
203 * 1 - byte MSTI Remaining Hops
204 *
205 */
206
207 #define MST_BPDU_MSTI_LENGTH 16
208 #define MST_BPDU_CONFIG_INFO_LENGTH 64
209
210 /* Offsets of fields from the begginning for the packet */
211 #define MST_BPDU_VER3_LEN_OFFSET 36
212 #define MST_BPDU_CONFIG_NAME_OFFSET 39
213 #define MST_BPDU_CONFIG_DIGEST_OFFSET 73
214 #define MST_BPDU_CIST_INT_PATH_COST_OFFSET 89
215 #define MST_BPDU_CIST_BRIDGE_ID_OFFSET 93
216 #define MST_BPDU_CIST_REMAIN_HOPS_OFFSET 101
217 #define MST_BPDU_MSTI_OFFSET 102
218 /* Offsets within an MSTI */
219 #define MST_BPDU_MSTI_ROOT_PRIO_OFFSET 1
220 #define MST_BPDU_MSTI_ROOT_PATH_COST_OFFSET 9
221 #define MST_BPDU_MSTI_BRIDGE_PRIO_OFFSET 13
222 #define MST_BPDU_MSTI_PORT_PRIO_OFFSET 14
223 #define MST_BPDU_MSTI_REMAIN_HOPS_OFFSET 15
224
225 #define SPB_BPDU_MIN_LEN 87
226 #define SPB_BPDU_CONFIG_NAME_OFFSET 3
227 #define SPB_BPDU_CONFIG_REV_OFFSET SPB_BPDU_CONFIG_NAME_OFFSET + 32
228 #define SPB_BPDU_CONFIG_DIGEST_OFFSET SPB_BPDU_CONFIG_REV_OFFSET + 2
229 #define SPB_BPDU_AGREEMENT_OFFSET SPB_BPDU_CONFIG_DIGEST_OFFSET + 16
230 #define SPB_BPDU_AGREEMENT_UNUSED_OFFSET SPB_BPDU_AGREEMENT_OFFSET + 1
231 #define SPB_BPDU_AGREEMENT_FORMAT_OFFSET SPB_BPDU_AGREEMENT_UNUSED_OFFSET + 1
232 #define SPB_BPDU_AGREEMENT_CON_OFFSET SPB_BPDU_AGREEMENT_FORMAT_OFFSET + 1
233 #define SPB_BPDU_AGREEMENT_EDGE_OFFSET SPB_BPDU_AGREEMENT_CON_OFFSET + 1
234 #define SPB_BPDU_AGREEMENT_RES1_OFFSET SPB_BPDU_AGREEMENT_EDGE_OFFSET + 2
235 #define SPB_BPDU_AGREEMENT_RES2_OFFSET SPB_BPDU_AGREEMENT_RES1_OFFSET + 4
236 #define SPB_BPDU_AGREEMENT_DIGEST_OFFSET SPB_BPDU_AGREEMENT_RES2_OFFSET + 4
237
238
239 static int
240 stp_print_mstp_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
241 u_int length)
242 {
243 const u_char *ptr;
244 uint16_t v3len;
245 uint16_t len;
246 uint16_t msti;
247 u_int offset;
248
249 ptr = (const u_char *)stp_bpdu;
250 ND_PRINT((ndo, ", CIST Flags [%s], length %u",
251 bittok2str(stp_bpdu_flag_values, "none", stp_bpdu->flags), length));
252
253 /*
254 * in non-verbose mode just print the flags.
255 */
256 if (!ndo->ndo_vflag) {
257 return 1;
258 }
259
260 ND_PRINT((ndo, "\n\tport-role %s, ",
261 tok2str(rstp_obj_port_role_values, "Unknown",
262 RSTP_EXTRACT_PORT_ROLE(stp_bpdu->flags))));
263
264 ND_TCHECK(stp_bpdu->root_path_cost);
265 ND_PRINT((ndo, "CIST root-id %s, CIST ext-pathcost %u ",
266 stp_print_bridge_id((const u_char *)&stp_bpdu->root_id),
267 EXTRACT_32BITS(&stp_bpdu->root_path_cost)));
268
269 ND_TCHECK(stp_bpdu->bridge_id);
270 ND_PRINT((ndo, "\n\tCIST regional-root-id %s, ",
271 stp_print_bridge_id((const u_char *)&stp_bpdu->bridge_id)));
272
273 ND_TCHECK(stp_bpdu->port_id);
274 ND_PRINT((ndo, "CIST port-id %04x, ", EXTRACT_16BITS(&stp_bpdu->port_id)));
275
276 ND_TCHECK(stp_bpdu->forward_delay);
277 ND_PRINT((ndo, "\n\tmessage-age %.2fs, max-age %.2fs"
278 ", hello-time %.2fs, forwarding-delay %.2fs",
279 (float)EXTRACT_16BITS(&stp_bpdu->message_age) / STP_TIME_BASE,
280 (float)EXTRACT_16BITS(&stp_bpdu->max_age) / STP_TIME_BASE,
281 (float)EXTRACT_16BITS(&stp_bpdu->hello_time) / STP_TIME_BASE,
282 (float)EXTRACT_16BITS(&stp_bpdu->forward_delay) / STP_TIME_BASE));
283
284 ND_TCHECK_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET);
285 ND_PRINT((ndo, "\n\tv3len %d, ", EXTRACT_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET)));
286 ND_TCHECK_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12);
287 ND_PRINT((ndo, "MCID Name %s, rev %u, "
288 "\n\t\tdigest %08x%08x%08x%08x, ",
289 ptr + MST_BPDU_CONFIG_NAME_OFFSET,
290 EXTRACT_16BITS(ptr + MST_BPDU_CONFIG_NAME_OFFSET + 32),
291 EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET),
292 EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 4),
293 EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 8),
294 EXTRACT_32BITS(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12)));
295
296 ND_TCHECK_32BITS(ptr + MST_BPDU_CIST_INT_PATH_COST_OFFSET);
297 ND_PRINT((ndo, "CIST int-root-pathcost %u, ",
298 EXTRACT_32BITS(ptr + MST_BPDU_CIST_INT_PATH_COST_OFFSET)));
299
300 ND_TCHECK_BRIDGE_ID(ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET);
301 ND_PRINT((ndo, "\n\tCIST bridge-id %s, ",
302 stp_print_bridge_id(ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET)));
303
304 ND_TCHECK(ptr[MST_BPDU_CIST_REMAIN_HOPS_OFFSET]);
305 ND_PRINT((ndo, "CIST remaining-hops %d", ptr[MST_BPDU_CIST_REMAIN_HOPS_OFFSET]));
306
307 /* Dump all MSTI's */
308 ND_TCHECK_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET);
309 v3len = EXTRACT_16BITS(ptr + MST_BPDU_VER3_LEN_OFFSET);
310 if (v3len > MST_BPDU_CONFIG_INFO_LENGTH) {
311 len = v3len - MST_BPDU_CONFIG_INFO_LENGTH;
312 offset = MST_BPDU_MSTI_OFFSET;
313 while (len >= MST_BPDU_MSTI_LENGTH) {
314 ND_TCHECK2(*(ptr + offset), MST_BPDU_MSTI_LENGTH);
315
316 msti = EXTRACT_16BITS(ptr + offset +
317 MST_BPDU_MSTI_ROOT_PRIO_OFFSET);
318 msti = msti & 0x0FFF;
319
320 ND_PRINT((ndo, "\n\tMSTI %d, Flags [%s], port-role %s",
321 msti, bittok2str(stp_bpdu_flag_values, "none", ptr[offset]),
322 tok2str(rstp_obj_port_role_values, "Unknown",
323 RSTP_EXTRACT_PORT_ROLE(ptr[offset]))));
324 ND_PRINT((ndo, "\n\t\tMSTI regional-root-id %s, pathcost %u",
325 stp_print_bridge_id(ptr + offset +
326 MST_BPDU_MSTI_ROOT_PRIO_OFFSET),
327 EXTRACT_32BITS(ptr + offset +
328 MST_BPDU_MSTI_ROOT_PATH_COST_OFFSET)));
329 ND_PRINT((ndo, "\n\t\tMSTI bridge-prio %d, port-prio %d, hops %d",
330 ptr[offset + MST_BPDU_MSTI_BRIDGE_PRIO_OFFSET] >> 4,
331 ptr[offset + MST_BPDU_MSTI_PORT_PRIO_OFFSET] >> 4,
332 ptr[offset + MST_BPDU_MSTI_REMAIN_HOPS_OFFSET]));
333
334 len -= MST_BPDU_MSTI_LENGTH;
335 offset += MST_BPDU_MSTI_LENGTH;
336 }
337 }
338 return 1;
339
340 trunc:
341 return 0;
342 }
343
344 static int
345 stp_print_spb_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
346 u_int offset)
347 {
348 const u_char *ptr;
349
350 /*
351 * in non-verbose mode don't print anything.
352 */
353 if (!ndo->ndo_vflag) {
354 return 1;
355 }
356
357 ptr = (const u_char *)stp_bpdu;
358 if (!ND_TTEST_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+16))
359 return 0;
360
361 ND_PRINT((ndo, "\n\tv4len %d AUXMCID Name %s, Rev %u, \n\t\tdigest %08x%08x%08x%08x",
362 EXTRACT_16BITS (ptr + offset),
363 ptr + offset + SPB_BPDU_CONFIG_NAME_OFFSET,
364 EXTRACT_16BITS(ptr + offset + SPB_BPDU_CONFIG_REV_OFFSET),
365 EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET),
366 EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 4),
367 EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 8),
368 EXTRACT_32BITS(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 12)));
369
370 ND_PRINT((ndo, "\n\tAgreement num %d, Discarded Agreement num %d, Agreement valid-"
371 "flag %d, \n\tRestricted role-flag: %d, Format id %d cap %d, "
372 "Convention id %d cap %d, \n\tEdge count %d, "
373 "Agreement digest %08x%08x%08x%08x%08x\n",
374 ptr[offset + SPB_BPDU_AGREEMENT_OFFSET]>>6,
375 ptr[offset + SPB_BPDU_AGREEMENT_OFFSET]>>4 & 0x3,
376 ptr[offset + SPB_BPDU_AGREEMENT_OFFSET]>>3 & 0x1,
377 ptr[offset + SPB_BPDU_AGREEMENT_OFFSET]>>2 & 0x1,
378 ptr[offset + SPB_BPDU_AGREEMENT_FORMAT_OFFSET]>>4,
379 ptr[offset + SPB_BPDU_AGREEMENT_FORMAT_OFFSET]&0x00ff,
380 ptr[offset + SPB_BPDU_AGREEMENT_CON_OFFSET]>>4,
381 ptr[offset + SPB_BPDU_AGREEMENT_CON_OFFSET]&0x00ff,
382 EXTRACT_16BITS(ptr + offset + SPB_BPDU_AGREEMENT_EDGE_OFFSET),
383 EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET),
384 EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+4),
385 EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+8),
386 EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+12),
387 EXTRACT_32BITS(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET+16)));
388 return 1;
389 }
390
391 /*
392 * Print 802.1d / 802.1w / 802.1q (mstp) / 802.1aq (spb) packets.
393 */
394 void
395 stp_print(netdissect_options *ndo, const u_char *p, u_int length)
396 {
397 const struct stp_bpdu_ *stp_bpdu;
398 u_int mstp_len;
399 u_int spb_len;
400
401 stp_bpdu = (const struct stp_bpdu_*)p;
402
403 /* Minimum STP Frame size. */
404 if (length < 4)
405 goto trunc;
406
407 ND_TCHECK(stp_bpdu->protocol_id);
408 if (EXTRACT_16BITS(&stp_bpdu->protocol_id)) {
409 ND_PRINT((ndo, "unknown STP version, length %u", length));
410 return;
411 }
412
413 ND_TCHECK(stp_bpdu->protocol_version);
414 ND_PRINT((ndo, "STP %s", tok2str(stp_proto_values, "Unknown STP protocol (0x%02x)",
415 stp_bpdu->protocol_version)));
416
417 switch (stp_bpdu->protocol_version) {
418 case STP_PROTO_REGULAR:
419 case STP_PROTO_RAPID:
420 case STP_PROTO_MSTP:
421 case STP_PROTO_SPB:
422 break;
423 default:
424 return;
425 }
426
427 ND_TCHECK(stp_bpdu->bpdu_type);
428 ND_PRINT((ndo, ", %s", tok2str(stp_bpdu_type_values, "Unknown BPDU Type (0x%02x)",
429 stp_bpdu->bpdu_type)));
430
431 switch (stp_bpdu->bpdu_type) {
432 case STP_BPDU_TYPE_CONFIG:
433 if (length < sizeof(struct stp_bpdu_) - 1) {
434 goto trunc;
435 }
436 if (!stp_print_config_bpdu(ndo, stp_bpdu, length))
437 goto trunc;
438 break;
439
440 case STP_BPDU_TYPE_RSTP:
441 if (stp_bpdu->protocol_version == STP_PROTO_RAPID) {
442 if (length < sizeof(struct stp_bpdu_)) {
443 goto trunc;
444 }
445 if (!stp_print_config_bpdu(ndo, stp_bpdu, length))
446 goto trunc;
447 } else if (stp_bpdu->protocol_version == STP_PROTO_MSTP ||
448 stp_bpdu->protocol_version == STP_PROTO_SPB) {
449 if (length < STP_BPDU_MSTP_MIN_LEN) {
450 goto trunc;
451 }
452
453 ND_TCHECK(stp_bpdu->v1_length);
454 if (stp_bpdu->v1_length != 0) {
455 /* FIX ME: Emit a message here ? */
456 goto trunc;
457 }
458
459 /* Validate v3 length */
460 ND_TCHECK_16BITS(p + MST_BPDU_VER3_LEN_OFFSET);
461 mstp_len = EXTRACT_16BITS(p + MST_BPDU_VER3_LEN_OFFSET);
462 mstp_len += 2; /* length encoding itself is 2 bytes */
463 if (length < (sizeof(struct stp_bpdu_) + mstp_len)) {
464 goto trunc;
465 }
466 if (!stp_print_mstp_bpdu(ndo, stp_bpdu, length))
467 goto trunc;
468
469 if (stp_bpdu->protocol_version == STP_PROTO_SPB)
470 {
471 /* Validate v4 length */
472 spb_len = EXTRACT_16BITS (p + MST_BPDU_VER3_LEN_OFFSET + mstp_len);
473 spb_len += 2;
474 if (length < (sizeof(struct stp_bpdu_) + mstp_len + spb_len) ||
475 spb_len < SPB_BPDU_MIN_LEN) {
476 goto trunc;
477 }
478 if (!stp_print_spb_bpdu(ndo, stp_bpdu, (sizeof(struct stp_bpdu_) + mstp_len)))
479 goto trunc;
480 }
481 }
482 break;
483
484 case STP_BPDU_TYPE_TOPO_CHANGE:
485 /* always empty message - just break out */
486 break;
487
488 default:
489 break;
490 }
491
492 return;
493 trunc:
494 ND_PRINT((ndo, "[|stp %d]", length));
495 }
496
497 /*
498 * Local Variables:
499 * c-style: whitesmith
500 * c-basic-offset: 4
501 * End:
502 */
[mirror] the TCPdump network dissector