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OpenFlow 1.3: Add initial partial support.
[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 nd_uint16_t protocol_id;
31 nd_uint8_t protocol_version;
32 nd_uint8_t bpdu_type;
33 nd_uint8_t flags;
34 nd_byte root_id[8];
35 nd_uint32_t root_path_cost;
36 nd_byte bridge_id[8];
37 nd_uint16_t port_id;
38 nd_uint16_t message_age;
39 nd_uint16_t max_age;
40 nd_uint16_t hello_time;
41 nd_uint16_t forward_delay;
42 nd_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_TCHECK_8(p)
88
89 static char *
90 stp_print_bridge_id(netdissect_options *ndo, 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 GET_U_1(p), GET_U_1(p + 1), GET_U_1(p + 2),
97 GET_U_1(p + 3), GET_U_1(p + 4), GET_U_1(p + 5),
98 GET_U_1(p + 6), GET_U_1(p + 7));
99
100 return bridge_id_str;
101 }
102
103 static int
104 stp_print_config_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
105 u_int length)
106 {
107 uint8_t bpdu_flags;
108
109 bpdu_flags = GET_U_1(stp_bpdu->flags);
110 ND_PRINT(", Flags [%s]",
111 bittok2str(stp_bpdu_flag_values, "none", bpdu_flags));
112
113 ND_PRINT(", bridge-id %s.%04x, length %u",
114 stp_print_bridge_id(ndo, stp_bpdu->bridge_id),
115 GET_BE_U_2(stp_bpdu->port_id), length);
116
117 /* in non-verbose mode just print the bridge-id */
118 if (!ndo->ndo_vflag) {
119 return 1;
120 }
121
122 ND_PRINT("\n\tmessage-age %.2fs, max-age %.2fs"
123 ", hello-time %.2fs, forwarding-delay %.2fs",
124 (float) GET_BE_U_2(stp_bpdu->message_age) / STP_TIME_BASE,
125 (float) GET_BE_U_2(stp_bpdu->max_age) / STP_TIME_BASE,
126 (float) GET_BE_U_2(stp_bpdu->hello_time) / STP_TIME_BASE,
127 (float) GET_BE_U_2(stp_bpdu->forward_delay) / STP_TIME_BASE);
128
129 ND_PRINT("\n\troot-id %s, root-pathcost %u",
130 stp_print_bridge_id(ndo, stp_bpdu->root_id),
131 GET_BE_U_4(stp_bpdu->root_path_cost));
132
133 /* Port role is only valid for 802.1w */
134 if (GET_U_1(stp_bpdu->protocol_version) == STP_PROTO_RAPID) {
135 ND_PRINT(", port-role %s",
136 tok2str(rstp_obj_port_role_values, "Unknown",
137 RSTP_EXTRACT_PORT_ROLE(bpdu_flags)));
138 }
139 return 1;
140 }
141
142 /*
143 * MSTP packet format
144 * Ref. IEEE 802.1Q 2003 Ed. Section 14
145 *
146 * MSTP BPDU
147 *
148 * 2 - bytes Protocol Id
149 * 1 - byte Protocol Ver.
150 * 1 - byte BPDU tye
151 * 1 - byte Flags
152 * 8 - bytes CIST Root Identifier
153 * 4 - bytes CIST External Path Cost
154 * 8 - bytes CIST Regional Root Identifier
155 * 2 - bytes CIST Port Identifier
156 * 2 - bytes Message Age
157 * 2 - bytes Max age
158 * 2 - bytes Hello Time
159 * 2 - bytes Forward delay
160 * 1 - byte Version 1 length. Must be 0
161 * 2 - bytes Version 3 length
162 * 1 - byte Config Identifier
163 * 32 - bytes Config Name
164 * 2 - bytes Revision level
165 * 16 - bytes Config Digest [MD5]
166 * 4 - bytes CIST Internal Root Path Cost
167 * 8 - bytes CIST Bridge Identifier
168 * 1 - byte CIST Remaining Hops
169 * 16 - bytes MSTI information [Max 64 MSTI, each 16 bytes]
170 *
171 *
172 * SPB BPDU
173 * Ref. IEEE 802.1aq. Section 14
174 *
175 * 2 - bytes Version 4 length
176 * 1 - byte Aux Config Identifier
177 * 32 - bytes Aux Config Name
178 * 2 - bytes Aux Revision level
179 * 16 - bytes Aux Config Digest [MD5]
180 * 1 - byte (1 - 2) Agreement Number
181 * (3 - 4) Discarded Agreement Number
182 * (5) Agreement Valid Flag
183 * (6) Restricted Role Flag
184 * (7 - 8) Unused sent zero
185 * 1 - byte Unused
186 * 1 - byte (1 - 4) Agreement Digest Format Identifier
187 * (5 - 8) Agreement Digest Format Capabilities
188 * 1 - byte (1 - 4) Agreement Digest Convention Identifier
189 * (5 - 8) Agreement Digest Convention Capabilities
190 * 2 - bytes Agreement Digest Edge Count
191 * 8 - byte Reserved Set
192 * 20 - bytes Computed Topology Digest
193 *
194 *
195 * MSTI Payload
196 *
197 * 1 - byte MSTI flag
198 * 8 - bytes MSTI Regional Root Identifier
199 * 4 - bytes MSTI Regional Path Cost
200 * 1 - byte MSTI Bridge Priority
201 * 1 - byte MSTI Port Priority
202 * 1 - byte MSTI Remaining Hops
203 *
204 */
205
206 #define MST_BPDU_MSTI_LENGTH 16
207 #define MST_BPDU_CONFIG_INFO_LENGTH 64
208
209 /* Offsets of fields from the begginning for the packet */
210 #define MST_BPDU_VER3_LEN_OFFSET 36
211 #define MST_BPDU_CONFIG_NAME_OFFSET 39
212 #define MST_BPDU_CONFIG_DIGEST_OFFSET 73
213 #define MST_BPDU_CIST_INT_PATH_COST_OFFSET 89
214 #define MST_BPDU_CIST_BRIDGE_ID_OFFSET 93
215 #define MST_BPDU_CIST_REMAIN_HOPS_OFFSET 101
216 #define MST_BPDU_MSTI_OFFSET 102
217 /* Offsets within an MSTI */
218 #define MST_BPDU_MSTI_ROOT_PRIO_OFFSET 1
219 #define MST_BPDU_MSTI_ROOT_PATH_COST_OFFSET 9
220 #define MST_BPDU_MSTI_BRIDGE_PRIO_OFFSET 13
221 #define MST_BPDU_MSTI_PORT_PRIO_OFFSET 14
222 #define MST_BPDU_MSTI_REMAIN_HOPS_OFFSET 15
223
224 #define SPB_BPDU_MIN_LEN 87
225 #define SPB_BPDU_CONFIG_NAME_OFFSET 3
226 #define SPB_BPDU_CONFIG_REV_OFFSET SPB_BPDU_CONFIG_NAME_OFFSET + 32
227 #define SPB_BPDU_CONFIG_DIGEST_OFFSET SPB_BPDU_CONFIG_REV_OFFSET + 2
228 #define SPB_BPDU_AGREEMENT_OFFSET SPB_BPDU_CONFIG_DIGEST_OFFSET + 16
229 #define SPB_BPDU_AGREEMENT_UNUSED_OFFSET SPB_BPDU_AGREEMENT_OFFSET + 1
230 #define SPB_BPDU_AGREEMENT_FORMAT_OFFSET SPB_BPDU_AGREEMENT_UNUSED_OFFSET + 1
231 #define SPB_BPDU_AGREEMENT_CON_OFFSET SPB_BPDU_AGREEMENT_FORMAT_OFFSET + 1
232 #define SPB_BPDU_AGREEMENT_EDGE_OFFSET SPB_BPDU_AGREEMENT_CON_OFFSET + 1
233 #define SPB_BPDU_AGREEMENT_RES1_OFFSET SPB_BPDU_AGREEMENT_EDGE_OFFSET + 2
234 #define SPB_BPDU_AGREEMENT_RES2_OFFSET SPB_BPDU_AGREEMENT_RES1_OFFSET + 4
235 #define SPB_BPDU_AGREEMENT_DIGEST_OFFSET SPB_BPDU_AGREEMENT_RES2_OFFSET + 4
236
237 static int
238 stp_print_mstp_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
239 u_int length)
240 {
241 const u_char *ptr;
242 uint8_t bpdu_flags;
243 uint16_t v3len;
244 uint16_t len;
245 uint16_t msti;
246 u_int offset;
247
248 ptr = (const u_char *)stp_bpdu;
249 bpdu_flags = GET_U_1(stp_bpdu->flags);
250 ND_PRINT(", CIST Flags [%s], length %u",
251 bittok2str(stp_bpdu_flag_values, "none", 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("\n\tport-role %s, ",
261 tok2str(rstp_obj_port_role_values, "Unknown",
262 RSTP_EXTRACT_PORT_ROLE(bpdu_flags)));
263
264 ND_PRINT("CIST root-id %s, CIST ext-pathcost %u",
265 stp_print_bridge_id(ndo, stp_bpdu->root_id),
266 GET_BE_U_4(stp_bpdu->root_path_cost));
267
268 ND_TCHECK_SIZE(&stp_bpdu->bridge_id);
269 ND_PRINT("\n\tCIST regional-root-id %s, ",
270 stp_print_bridge_id(ndo, stp_bpdu->bridge_id));
271
272 ND_PRINT("CIST port-id %04x,", GET_BE_U_2(stp_bpdu->port_id));
273
274 ND_PRINT("\n\tmessage-age %.2fs, max-age %.2fs"
275 ", hello-time %.2fs, forwarding-delay %.2fs",
276 (float) GET_BE_U_2(stp_bpdu->message_age) / STP_TIME_BASE,
277 (float) GET_BE_U_2(stp_bpdu->max_age) / STP_TIME_BASE,
278 (float) GET_BE_U_2(stp_bpdu->hello_time) / STP_TIME_BASE,
279 (float) GET_BE_U_2(stp_bpdu->forward_delay) / STP_TIME_BASE);
280
281 ND_PRINT("\n\tv3len %u, ", GET_BE_U_2(ptr + MST_BPDU_VER3_LEN_OFFSET));
282 ND_TCHECK_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12);
283 ND_PRINT("MCID Name ");
284 if (nd_printzp(ndo, ptr + MST_BPDU_CONFIG_NAME_OFFSET, 32, ndo->ndo_snapend))
285 goto trunc;
286 ND_PRINT(", rev %u,"
287 "\n\t\tdigest %08x%08x%08x%08x, ",
288 GET_BE_U_2(ptr + MST_BPDU_CONFIG_NAME_OFFSET + 32),
289 GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET),
290 GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 4),
291 GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 8),
292 GET_BE_U_4(ptr + MST_BPDU_CONFIG_DIGEST_OFFSET + 12));
293
294 ND_PRINT("CIST int-root-pathcost %u,",
295 GET_BE_U_4(ptr + MST_BPDU_CIST_INT_PATH_COST_OFFSET));
296
297 ND_TCHECK_BRIDGE_ID(ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET);
298 ND_PRINT("\n\tCIST bridge-id %s, ",
299 stp_print_bridge_id(ndo, ptr + MST_BPDU_CIST_BRIDGE_ID_OFFSET));
300
301 ND_PRINT("CIST remaining-hops %u",
302 GET_U_1(ptr + MST_BPDU_CIST_REMAIN_HOPS_OFFSET));
303
304 /* Dump all MSTI's */
305 v3len = GET_BE_U_2(ptr + MST_BPDU_VER3_LEN_OFFSET);
306 if (v3len > MST_BPDU_CONFIG_INFO_LENGTH) {
307 len = v3len - MST_BPDU_CONFIG_INFO_LENGTH;
308 offset = MST_BPDU_MSTI_OFFSET;
309 while (len >= MST_BPDU_MSTI_LENGTH) {
310 ND_TCHECK_LEN(ptr + offset, MST_BPDU_MSTI_LENGTH);
311
312 msti = GET_BE_U_2(ptr + offset + MST_BPDU_MSTI_ROOT_PRIO_OFFSET);
313 msti = msti & 0x0FFF;
314
315 ND_PRINT("\n\tMSTI %u, Flags [%s], port-role %s",
316 msti,
317 bittok2str(stp_bpdu_flag_values, "none", GET_U_1(ptr + offset)),
318 tok2str(rstp_obj_port_role_values, "Unknown",
319 RSTP_EXTRACT_PORT_ROLE(GET_U_1(ptr + offset))));
320 ND_PRINT("\n\t\tMSTI regional-root-id %s, pathcost %u",
321 stp_print_bridge_id(ndo, ptr + offset +
322 MST_BPDU_MSTI_ROOT_PRIO_OFFSET),
323 GET_BE_U_4(ptr + offset + MST_BPDU_MSTI_ROOT_PATH_COST_OFFSET));
324 ND_PRINT("\n\t\tMSTI bridge-prio %u, port-prio %u, hops %u",
325 GET_U_1(ptr + offset + MST_BPDU_MSTI_BRIDGE_PRIO_OFFSET) >> 4,
326 GET_U_1(ptr + offset + MST_BPDU_MSTI_PORT_PRIO_OFFSET) >> 4,
327 GET_U_1(ptr + offset + MST_BPDU_MSTI_REMAIN_HOPS_OFFSET));
328
329 len -= MST_BPDU_MSTI_LENGTH;
330 offset += MST_BPDU_MSTI_LENGTH;
331 }
332 }
333 return 1;
334
335 trunc:
336 return 0;
337 }
338
339 static int
340 stp_print_spb_bpdu(netdissect_options *ndo, const struct stp_bpdu_ *stp_bpdu,
341 u_int offset)
342 {
343 const u_char *ptr;
344
345 /*
346 * in non-verbose mode don't print anything.
347 */
348 if (!ndo->ndo_vflag) {
349 return 1;
350 }
351
352 ptr = (const u_char *)stp_bpdu;
353 ND_TCHECK_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 16);
354
355 ND_PRINT("\n\tv4len %u, ", GET_BE_U_2(ptr + offset));
356 ND_PRINT("AUXMCID Name ");
357 if (nd_printzp(ndo, ptr + offset + SPB_BPDU_CONFIG_NAME_OFFSET, 32,
358 ndo->ndo_snapend))
359 goto trunc;
360 ND_PRINT(", Rev %u,\n\t\tdigest %08x%08x%08x%08x",
361 GET_BE_U_2(ptr + offset + SPB_BPDU_CONFIG_REV_OFFSET),
362 GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET),
363 GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 4),
364 GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 8),
365 GET_BE_U_4(ptr + offset + SPB_BPDU_CONFIG_DIGEST_OFFSET + 12));
366
367 ND_PRINT("\n\tAgreement num %u, Discarded Agreement num %u, Agreement valid-"
368 "flag %u,\n\tRestricted role-flag: %u, Format id %u cap %u, "
369 "Convention id %u cap %u,\n\tEdge count %u, "
370 "Agreement digest %08x%08x%08x%08x%08x",
371 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>6,
372 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>4 & 0x3,
373 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>3 & 0x1,
374 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_OFFSET)>>2 & 0x1,
375 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_FORMAT_OFFSET)>>4,
376 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_FORMAT_OFFSET)&0x00ff,
377 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_CON_OFFSET)>>4,
378 GET_U_1(ptr + offset + SPB_BPDU_AGREEMENT_CON_OFFSET)&0x00ff,
379 GET_BE_U_2(ptr + offset + SPB_BPDU_AGREEMENT_EDGE_OFFSET),
380 GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET),
381 GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 4),
382 GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 8),
383 GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 12),
384 GET_BE_U_4(ptr + offset + SPB_BPDU_AGREEMENT_DIGEST_OFFSET + 16));
385 return 1;
386
387 trunc:
388 return 0;
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 protocol_version;
399 u_int bpdu_type;
400 u_int mstp_len;
401 u_int spb_len;
402
403 ndo->ndo_protocol = "stp";
404 stp_bpdu = (const struct stp_bpdu_*)p;
405
406 /* Minimum STP Frame size. */
407 if (length < 4)
408 goto trunc;
409
410 if (GET_BE_U_2(stp_bpdu->protocol_id)) {
411 ND_PRINT("unknown STP version, length %u", length);
412 return;
413 }
414
415 protocol_version = GET_U_1(stp_bpdu->protocol_version);
416 ND_PRINT("STP %s", tok2str(stp_proto_values, "Unknown STP protocol (0x%02x)",
417 protocol_version));
418
419 switch (protocol_version) {
420 case STP_PROTO_REGULAR:
421 case STP_PROTO_RAPID:
422 case STP_PROTO_MSTP:
423 case STP_PROTO_SPB:
424 break;
425 default:
426 return;
427 }
428
429 bpdu_type = GET_U_1(stp_bpdu->bpdu_type);
430 ND_PRINT(", %s", tok2str(stp_bpdu_type_values, "Unknown BPDU Type (0x%02x)",
431 bpdu_type));
432
433 switch (bpdu_type) {
434 case STP_BPDU_TYPE_CONFIG:
435 if (length < sizeof(struct stp_bpdu_) - 1) {
436 goto trunc;
437 }
438 if (!stp_print_config_bpdu(ndo, stp_bpdu, length))
439 goto trunc;
440 break;
441
442 case STP_BPDU_TYPE_RSTP:
443 if (protocol_version == STP_PROTO_RAPID) {
444 if (length < sizeof(struct stp_bpdu_)) {
445 goto trunc;
446 }
447 if (!stp_print_config_bpdu(ndo, stp_bpdu, length))
448 goto trunc;
449 } else if (protocol_version == STP_PROTO_MSTP ||
450 protocol_version == STP_PROTO_SPB) {
451 if (length < STP_BPDU_MSTP_MIN_LEN) {
452 goto trunc;
453 }
454
455 if (GET_U_1(stp_bpdu->v1_length) != 0) {
456 /* FIX ME: Emit a message here ? */
457 goto trunc;
458 }
459
460 /* Validate v3 length */
461 mstp_len = GET_BE_U_2(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 (protocol_version == STP_PROTO_SPB)
470 {
471 /* Validate v4 length */
472 spb_len = GET_BE_U_2(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_trunc(ndo);
495 }
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