bridgestp.c revision 1.7.12.1 1 /* $NetBSD: bridgestp.c,v 1.7.12.1 2006/05/24 15:50:43 tron Exp $ */
2
3 /*
4 * Copyright (c) 2000 Jason L. Wright (jason (at) thought.net)
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Jason L. Wright
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
26 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
27 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
29 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
30 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 *
33 * OpenBSD: bridgestp.c,v 1.5 2001/03/22 03:48:29 jason Exp
34 */
35
36 /*
37 * Implementation of the spanning tree protocol as defined in
38 * ISO/IEC Final DIS 15802-3 (IEEE P802.1D/D17), May 25, 1998.
39 * (In English: IEEE 802.1D, Draft 17, 1998)
40 */
41
42 #include <sys/cdefs.h>
43 __KERNEL_RCSID(0, "$NetBSD: bridgestp.c,v 1.7.12.1 2006/05/24 15:50:43 tron Exp $");
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/mbuf.h>
48 #include <sys/socket.h>
49 #include <sys/ioctl.h>
50 #include <sys/device.h>
51 #include <sys/kernel.h>
52 #include <sys/callout.h>
53
54 #include <net/if.h>
55 #include <net/if_dl.h>
56 #include <net/if_types.h>
57 #include <net/if_llc.h>
58
59 #include <net/if_ether.h>
60 #include <net/if_bridgevar.h>
61
62 /* BPDU message types */
63 #define BSTP_MSGTYPE_CFG 0x00 /* Configuration */
64 #define BSTP_MSGTYPE_TCN 0x80 /* Topology chg notification */
65
66 /* BPDU flags */
67 #define BSTP_FLAG_TC 0x01 /* Topology change */
68 #define BSTP_FLAG_TCA 0x80 /* Topology change ack */
69
70 #define BSTP_MESSAGE_AGE_INCR (1 * 256) /* in 256ths of a second */
71 #define BSTP_TICK_VAL (1 * 256) /* in 256ths of a second */
72
73 /*
74 * Because BPDU's do not make nicely aligned structures, two different
75 * declarations are used: bstp_?bpdu (wire representation, packed) and
76 * bstp_*_unit (internal, nicely aligned version).
77 */
78
79 /* configuration bridge protocol data unit */
80 struct bstp_cbpdu {
81 uint8_t cbu_dsap; /* LLC: destination sap */
82 uint8_t cbu_ssap; /* LLC: source sap */
83 uint8_t cbu_ctl; /* LLC: control */
84 uint16_t cbu_protoid; /* protocol id */
85 uint8_t cbu_protover; /* protocol version */
86 uint8_t cbu_bpdutype; /* message type */
87 uint8_t cbu_flags; /* flags (below) */
88
89 /* root id */
90 uint16_t cbu_rootpri; /* root priority */
91 uint8_t cbu_rootaddr[6]; /* root address */
92
93 uint32_t cbu_rootpathcost; /* root path cost */
94
95 /* bridge id */
96 uint16_t cbu_bridgepri; /* bridge priority */
97 uint8_t cbu_bridgeaddr[6]; /* bridge address */
98
99 uint16_t cbu_portid; /* port id */
100 uint16_t cbu_messageage; /* current message age */
101 uint16_t cbu_maxage; /* maximum age */
102 uint16_t cbu_hellotime; /* hello time */
103 uint16_t cbu_forwarddelay; /* forwarding delay */
104 } __attribute__((__packed__));
105
106 /* topology change notification bridge protocol data unit */
107 struct bstp_tbpdu {
108 uint8_t tbu_dsap; /* LLC: destination sap */
109 uint8_t tbu_ssap; /* LLC: source sap */
110 uint8_t tbu_ctl; /* LLC: control */
111 uint16_t tbu_protoid; /* protocol id */
112 uint8_t tbu_protover; /* protocol version */
113 uint8_t tbu_bpdutype; /* message type */
114 } __attribute__((__packed__));
115
116 const uint8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
117
118 void bstp_initialize_port(struct bridge_softc *, struct bridge_iflist *);
119 void bstp_ifupdstatus(struct bridge_softc *, struct bridge_iflist *);
120 void bstp_enable_port(struct bridge_softc *, struct bridge_iflist *);
121 void bstp_disable_port(struct bridge_softc *, struct bridge_iflist *);
122 void bstp_enable_change_detection(struct bridge_iflist *);
123 void bstp_disable_change_detection(struct bridge_iflist *);
124 int bstp_root_bridge(struct bridge_softc *sc);
125 int bstp_supersedes_port_info(struct bridge_softc *,
126 struct bridge_iflist *, struct bstp_config_unit *);
127 int bstp_designated_port(struct bridge_softc *, struct bridge_iflist *);
128 int bstp_designated_for_some_port(struct bridge_softc *);
129 void bstp_transmit_config(struct bridge_softc *, struct bridge_iflist *);
130 void bstp_transmit_tcn(struct bridge_softc *);
131 void bstp_received_config_bpdu(struct bridge_softc *,
132 struct bridge_iflist *, struct bstp_config_unit *);
133 void bstp_received_tcn_bpdu(struct bridge_softc *, struct bridge_iflist *,
134 struct bstp_tcn_unit *);
135 void bstp_record_config_information(struct bridge_softc *,
136 struct bridge_iflist *, struct bstp_config_unit *);
137 void bstp_record_config_timeout_values(struct bridge_softc *,
138 struct bstp_config_unit *);
139 void bstp_config_bpdu_generation(struct bridge_softc *);
140 void bstp_send_config_bpdu(struct bridge_softc *, struct bridge_iflist *,
141 struct bstp_config_unit *);
142 void bstp_configuration_update(struct bridge_softc *);
143 void bstp_root_selection(struct bridge_softc *);
144 void bstp_designated_port_selection(struct bridge_softc *);
145 void bstp_become_designated_port(struct bridge_softc *,
146 struct bridge_iflist *);
147 void bstp_port_state_selection(struct bridge_softc *);
148 void bstp_make_forwarding(struct bridge_softc *, struct bridge_iflist *);
149 void bstp_make_blocking(struct bridge_softc *, struct bridge_iflist *);
150 void bstp_set_port_state(struct bridge_iflist *, uint8_t);
151 void bstp_set_bridge_priority(struct bridge_softc *, uint64_t);
152 void bstp_set_port_priority(struct bridge_softc *, struct bridge_iflist *,
153 uint16_t);
154 void bstp_set_path_cost(struct bridge_softc *, struct bridge_iflist *,
155 uint32_t);
156 void bstp_topology_change_detection(struct bridge_softc *);
157 void bstp_topology_change_acknowledged(struct bridge_softc *);
158 void bstp_acknowledge_topology_change(struct bridge_softc *,
159 struct bridge_iflist *);
160
161 void bstp_tick(void *);
162 void bstp_timer_start(struct bridge_timer *, uint16_t);
163 void bstp_timer_stop(struct bridge_timer *);
164 int bstp_timer_expired(struct bridge_timer *, uint16_t);
165
166 void bstp_hold_timer_expiry(struct bridge_softc *, struct bridge_iflist *);
167 void bstp_message_age_timer_expiry(struct bridge_softc *,
168 struct bridge_iflist *);
169 void bstp_forward_delay_timer_expiry(struct bridge_softc *,
170 struct bridge_iflist *);
171 void bstp_topology_change_timer_expiry(struct bridge_softc *);
172 void bstp_tcn_timer_expiry(struct bridge_softc *);
173 void bstp_hello_timer_expiry(struct bridge_softc *);
174
175 void
176 bstp_transmit_config(struct bridge_softc *sc, struct bridge_iflist *bif)
177 {
178 if (bif->bif_hold_timer.active) {
179 bif->bif_config_pending = 1;
180 return;
181 }
182
183 bif->bif_config_bpdu.cu_message_type = BSTP_MSGTYPE_CFG;
184 bif->bif_config_bpdu.cu_rootid = sc->sc_designated_root;
185 bif->bif_config_bpdu.cu_root_path_cost = sc->sc_root_path_cost;
186 bif->bif_config_bpdu.cu_bridge_id = sc->sc_bridge_id;
187 bif->bif_config_bpdu.cu_port_id = bif->bif_port_id;
188
189 if (bstp_root_bridge(sc))
190 bif->bif_config_bpdu.cu_message_age = 0;
191 else
192 bif->bif_config_bpdu.cu_message_age =
193 sc->sc_root_port->bif_message_age_timer.value +
194 BSTP_MESSAGE_AGE_INCR;
195
196 bif->bif_config_bpdu.cu_max_age = sc->sc_max_age;
197 bif->bif_config_bpdu.cu_hello_time = sc->sc_hello_time;
198 bif->bif_config_bpdu.cu_forward_delay = sc->sc_forward_delay;
199 bif->bif_config_bpdu.cu_topology_change_acknowledgment
200 = bif->bif_topology_change_acknowledge;
201 bif->bif_config_bpdu.cu_topology_change = sc->sc_topology_change;
202
203 if (bif->bif_config_bpdu.cu_message_age < sc->sc_max_age) {
204 bif->bif_topology_change_acknowledge = 0;
205 bif->bif_config_pending = 0;
206 bstp_send_config_bpdu(sc, bif, &bif->bif_config_bpdu);
207 bstp_timer_start(&bif->bif_hold_timer, 0);
208 }
209 }
210
211 void
212 bstp_send_config_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif,
213 struct bstp_config_unit *cu)
214 {
215 struct ifnet *ifp;
216 struct mbuf *m;
217 struct ether_header *eh;
218 struct bstp_cbpdu bpdu;
219 int s;
220
221 ifp = bif->bif_ifp;
222
223 if ((ifp->if_flags & IFF_RUNNING) == 0)
224 return;
225
226 MGETHDR(m, M_DONTWAIT, MT_DATA);
227 if (m == NULL)
228 return;
229
230 eh = mtod(m, struct ether_header *);
231
232 m->m_pkthdr.rcvif = ifp;
233 m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
234 m->m_len = m->m_pkthdr.len;
235
236 bpdu.cbu_ssap = bpdu.cbu_dsap = LLC_8021D_LSAP;
237 bpdu.cbu_ctl = LLC_UI;
238 bpdu.cbu_protoid = htons(0);
239 bpdu.cbu_protover = 0;
240 bpdu.cbu_bpdutype = cu->cu_message_type;
241 bpdu.cbu_flags = (cu->cu_topology_change ? BSTP_FLAG_TC : 0) |
242 (cu->cu_topology_change_acknowledgment ? BSTP_FLAG_TCA : 0);
243
244 bpdu.cbu_rootpri = htons(cu->cu_rootid >> 48);
245 bpdu.cbu_rootaddr[0] = cu->cu_rootid >> 40;
246 bpdu.cbu_rootaddr[1] = cu->cu_rootid >> 32;
247 bpdu.cbu_rootaddr[2] = cu->cu_rootid >> 24;
248 bpdu.cbu_rootaddr[3] = cu->cu_rootid >> 16;
249 bpdu.cbu_rootaddr[4] = cu->cu_rootid >> 8;
250 bpdu.cbu_rootaddr[5] = cu->cu_rootid >> 0;
251
252 bpdu.cbu_rootpathcost = htonl(cu->cu_root_path_cost);
253
254 bpdu.cbu_bridgepri = htons(cu->cu_rootid >> 48);
255 bpdu.cbu_bridgeaddr[0] = cu->cu_rootid >> 40;
256 bpdu.cbu_bridgeaddr[1] = cu->cu_rootid >> 32;
257 bpdu.cbu_bridgeaddr[2] = cu->cu_rootid >> 24;
258 bpdu.cbu_bridgeaddr[3] = cu->cu_rootid >> 16;
259 bpdu.cbu_bridgeaddr[4] = cu->cu_rootid >> 8;
260 bpdu.cbu_bridgeaddr[5] = cu->cu_rootid >> 0;
261
262 bpdu.cbu_portid = htons(cu->cu_port_id);
263 bpdu.cbu_messageage = htons(cu->cu_message_age);
264 bpdu.cbu_maxage = htons(cu->cu_max_age);
265 bpdu.cbu_hellotime = htons(cu->cu_hello_time);
266 bpdu.cbu_forwarddelay = htons(cu->cu_forward_delay);
267
268 memcpy(eh->ether_shost, LLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
269 memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
270 eh->ether_type = htons(sizeof(bpdu));
271
272 memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu));
273
274 s = splnet();
275 bridge_enqueue(sc, ifp, m, 0);
276 splx(s);
277 }
278
279 int
280 bstp_root_bridge(struct bridge_softc *sc)
281 {
282 return (sc->sc_designated_root == sc->sc_bridge_id);
283 }
284
285 int
286 bstp_supersedes_port_info(struct bridge_softc *sc, struct bridge_iflist *bif,
287 struct bstp_config_unit *cu)
288 {
289 if (cu->cu_rootid < bif->bif_designated_root)
290 return (1);
291 if (cu->cu_rootid > bif->bif_designated_root)
292 return (0);
293
294 if (cu->cu_root_path_cost < bif->bif_designated_cost)
295 return (1);
296 if (cu->cu_root_path_cost > bif->bif_designated_cost)
297 return (0);
298
299 if (cu->cu_bridge_id < bif->bif_designated_bridge)
300 return (1);
301 if (cu->cu_bridge_id > bif->bif_designated_bridge)
302 return (0);
303
304 if (sc->sc_bridge_id != cu->cu_bridge_id)
305 return (1);
306 if (cu->cu_port_id <= bif->bif_designated_port)
307 return (1);
308 return (0);
309 }
310
311 void
312 bstp_record_config_information(struct bridge_softc *sc,
313 struct bridge_iflist *bif, struct bstp_config_unit *cu)
314 {
315 bif->bif_designated_root = cu->cu_rootid;
316 bif->bif_designated_cost = cu->cu_root_path_cost;
317 bif->bif_designated_bridge = cu->cu_bridge_id;
318 bif->bif_designated_port = cu->cu_port_id;
319 bstp_timer_start(&bif->bif_message_age_timer, cu->cu_message_age);
320 }
321
322 void
323 bstp_record_config_timeout_values(struct bridge_softc *sc,
324 struct bstp_config_unit *config)
325 {
326 sc->sc_max_age = config->cu_max_age;
327 sc->sc_hello_time = config->cu_hello_time;
328 sc->sc_forward_delay = config->cu_forward_delay;
329 sc->sc_topology_change = config->cu_topology_change;
330 }
331
332 void
333 bstp_config_bpdu_generation(struct bridge_softc *sc)
334 {
335 struct bridge_iflist *bif;
336
337 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
338 if ((bif->bif_flags & IFBIF_STP) == 0)
339 continue;
340 if (bstp_designated_port(sc, bif) &&
341 (bif->bif_state != BSTP_IFSTATE_DISABLED))
342 bstp_transmit_config(sc, bif);
343 }
344 }
345
346 int
347 bstp_designated_port(struct bridge_softc *sc, struct bridge_iflist *bif)
348 {
349 return ((bif->bif_designated_bridge == sc->sc_bridge_id)
350 && (bif->bif_designated_port == bif->bif_port_id));
351 }
352
353 void
354 bstp_transmit_tcn(struct bridge_softc *sc)
355 {
356 struct bstp_tbpdu bpdu;
357 struct bridge_iflist *bif = sc->sc_root_port;
358 struct ifnet *ifp;
359 struct ether_header *eh;
360 struct mbuf *m;
361 int s;
362
363 KASSERT(bif != NULL);
364 ifp = bif->bif_ifp;
365 if ((ifp->if_flags & IFF_RUNNING) == 0)
366 return;
367
368 MGETHDR(m, M_DONTWAIT, MT_DATA);
369 if (m == NULL)
370 return;
371
372 m->m_pkthdr.rcvif = ifp;
373 m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
374 m->m_len = m->m_pkthdr.len;
375
376 eh = mtod(m, struct ether_header *);
377
378 memcpy(eh->ether_shost, LLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
379 memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
380 eh->ether_type = htons(sizeof(bpdu));
381
382 bpdu.tbu_ssap = bpdu.tbu_dsap = LLC_8021D_LSAP;
383 bpdu.tbu_ctl = LLC_UI;
384 bpdu.tbu_protoid = 0;
385 bpdu.tbu_protover = 0;
386 bpdu.tbu_bpdutype = BSTP_MSGTYPE_TCN;
387
388 memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu));
389
390 s = splnet();
391 bridge_enqueue(sc, ifp, m, 0);
392 splx(s);
393 }
394
395 void
396 bstp_configuration_update(struct bridge_softc *sc)
397 {
398 bstp_root_selection(sc);
399 bstp_designated_port_selection(sc);
400 }
401
402 void
403 bstp_root_selection(struct bridge_softc *sc)
404 {
405 struct bridge_iflist *root_port = NULL, *bif;
406
407 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
408 if ((bif->bif_flags & IFBIF_STP) == 0)
409 continue;
410 if (bstp_designated_port(sc, bif))
411 continue;
412 if (bif->bif_state == BSTP_IFSTATE_DISABLED)
413 continue;
414 if (bif->bif_designated_root >= sc->sc_bridge_id)
415 continue;
416 if (root_port == NULL)
417 goto set_port;
418
419 if (bif->bif_designated_root < root_port->bif_designated_root)
420 goto set_port;
421 if (bif->bif_designated_root > root_port->bif_designated_root)
422 continue;
423
424 if ((bif->bif_designated_cost + bif->bif_path_cost) <
425 (root_port->bif_designated_cost + root_port->bif_path_cost))
426 goto set_port;
427 if ((bif->bif_designated_cost + bif->bif_path_cost) >
428 (root_port->bif_designated_cost + root_port->bif_path_cost))
429 continue;
430
431 if (bif->bif_designated_bridge <
432 root_port->bif_designated_bridge)
433 goto set_port;
434 if (bif->bif_designated_bridge >
435 root_port->bif_designated_bridge)
436 continue;
437
438 if (bif->bif_designated_port < root_port->bif_designated_port)
439 goto set_port;
440 if (bif->bif_designated_port > root_port->bif_designated_port)
441 continue;
442
443 if (bif->bif_port_id >= root_port->bif_port_id)
444 continue;
445 set_port:
446 root_port = bif;
447 }
448
449 sc->sc_root_port = root_port;
450 if (root_port == NULL) {
451 sc->sc_designated_root = sc->sc_bridge_id;
452 sc->sc_root_path_cost = 0;
453 } else {
454 sc->sc_designated_root = root_port->bif_designated_root;
455 sc->sc_root_path_cost = root_port->bif_designated_cost +
456 root_port->bif_path_cost;
457 }
458 }
459
460 void
461 bstp_designated_port_selection(struct bridge_softc *sc)
462 {
463 struct bridge_iflist *bif;
464
465 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
466 if ((bif->bif_flags & IFBIF_STP) == 0)
467 continue;
468 if (bstp_designated_port(sc, bif))
469 goto designated;
470 if (bif->bif_designated_root != sc->sc_designated_root)
471 goto designated;
472
473 if (sc->sc_root_path_cost < bif->bif_designated_cost)
474 goto designated;
475 if (sc->sc_root_path_cost > bif->bif_designated_cost)
476 continue;
477
478 if (sc->sc_bridge_id < bif->bif_designated_bridge)
479 goto designated;
480 if (sc->sc_bridge_id > bif->bif_designated_bridge)
481 continue;
482
483 if (bif->bif_port_id > bif->bif_designated_port)
484 continue;
485 designated:
486 bstp_become_designated_port(sc, bif);
487 }
488 }
489
490 void
491 bstp_become_designated_port(struct bridge_softc *sc, struct bridge_iflist *bif)
492 {
493 bif->bif_designated_root = sc->sc_designated_root;
494 bif->bif_designated_cost = sc->sc_root_path_cost;
495 bif->bif_designated_bridge = sc->sc_bridge_id;
496 bif->bif_designated_port = bif->bif_port_id;
497 }
498
499 void
500 bstp_port_state_selection(struct bridge_softc *sc)
501 {
502 struct bridge_iflist *bif;
503
504 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
505 if ((bif->bif_flags & IFBIF_STP) == 0)
506 continue;
507 if (bif == sc->sc_root_port) {
508 bif->bif_config_pending = 0;
509 bif->bif_topology_change_acknowledge = 0;
510 bstp_make_forwarding(sc, bif);
511 } else if (bstp_designated_port(sc, bif)) {
512 bstp_timer_stop(&bif->bif_message_age_timer);
513 bstp_make_forwarding(sc, bif);
514 } else {
515 bif->bif_config_pending = 0;
516 bif->bif_topology_change_acknowledge = 0;
517 bstp_make_blocking(sc, bif);
518 }
519 }
520 }
521
522 void
523 bstp_make_forwarding(struct bridge_softc *sc, struct bridge_iflist *bif)
524 {
525 if (bif->bif_state == BSTP_IFSTATE_BLOCKING) {
526 bstp_set_port_state(bif, BSTP_IFSTATE_LISTENING);
527 bstp_timer_start(&bif->bif_forward_delay_timer, 0);
528 }
529 }
530
531 void
532 bstp_make_blocking(struct bridge_softc *sc, struct bridge_iflist *bif)
533 {
534 if ((bif->bif_state != BSTP_IFSTATE_DISABLED) &&
535 (bif->bif_state != BSTP_IFSTATE_BLOCKING)) {
536 if ((bif->bif_state == BSTP_IFSTATE_FORWARDING) ||
537 (bif->bif_state == BSTP_IFSTATE_LEARNING)) {
538 if (bif->bif_change_detection_enabled) {
539 bstp_topology_change_detection(sc);
540 }
541 }
542 bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING);
543 bstp_timer_stop(&bif->bif_forward_delay_timer);
544 }
545 }
546
547 void
548 bstp_set_port_state(struct bridge_iflist *bif, uint8_t state)
549 {
550 bif->bif_state = state;
551 }
552
553 void
554 bstp_topology_change_detection(struct bridge_softc *sc)
555 {
556 if (bstp_root_bridge(sc)) {
557 sc->sc_topology_change = 1;
558 bstp_timer_start(&sc->sc_topology_change_timer, 0);
559 } else if (!sc->sc_topology_change_detected) {
560 bstp_transmit_tcn(sc);
561 bstp_timer_start(&sc->sc_tcn_timer, 0);
562 }
563 sc->sc_topology_change_detected = 1;
564 }
565
566 void
567 bstp_topology_change_acknowledged(struct bridge_softc *sc)
568 {
569 sc->sc_topology_change_detected = 0;
570 bstp_timer_stop(&sc->sc_tcn_timer);
571 }
572
573 void
574 bstp_acknowledge_topology_change(struct bridge_softc *sc,
575 struct bridge_iflist *bif)
576 {
577 bif->bif_topology_change_acknowledge = 1;
578 bstp_transmit_config(sc, bif);
579 }
580
581 struct mbuf *
582 bstp_input(struct ifnet *ifp, struct mbuf *m)
583 {
584 struct bridge_softc *sc = ifp->if_bridge;
585 struct bridge_iflist *bif = NULL;
586 struct ether_header *eh;
587 struct bstp_tbpdu tpdu;
588 struct bstp_cbpdu cpdu;
589 struct bstp_config_unit cu;
590 struct bstp_tcn_unit tu;
591 uint16_t len;
592
593 eh = mtod(m, struct ether_header *);
594
595 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
596 if ((bif->bif_flags & IFBIF_STP) == 0)
597 continue;
598 if (bif->bif_ifp == ifp)
599 break;
600 }
601 if (bif == NULL)
602 goto out;
603
604 len = ntohs(eh->ether_type);
605 if (len < sizeof(tpdu))
606 goto out;
607
608 m_adj(m, ETHER_HDR_LEN);
609
610 if (m->m_pkthdr.len > len)
611 m_adj(m, len - m->m_pkthdr.len);
612 if (m->m_len < sizeof(tpdu) &&
613 (m = m_pullup(m, sizeof(tpdu))) == NULL)
614 goto out;
615
616 memcpy(&tpdu, mtod(m, caddr_t), sizeof(tpdu));
617
618 if (tpdu.tbu_dsap != LLC_8021D_LSAP ||
619 tpdu.tbu_ssap != LLC_8021D_LSAP ||
620 tpdu.tbu_ctl != LLC_UI)
621 goto out;
622 if (tpdu.tbu_protoid != 0 || tpdu.tbu_protover != 0)
623 goto out;
624
625 switch (tpdu.tbu_bpdutype) {
626 case BSTP_MSGTYPE_TCN:
627 tu.tu_message_type = tpdu.tbu_bpdutype;
628 bstp_received_tcn_bpdu(sc, bif, &tu);
629 break;
630 case BSTP_MSGTYPE_CFG:
631 if (m->m_len < sizeof(cpdu) &&
632 (m = m_pullup(m, sizeof(cpdu))) == NULL)
633 goto out;
634 memcpy(&cpdu, mtod(m, caddr_t), sizeof(cpdu));
635
636 cu.cu_rootid =
637 (((uint64_t)ntohs(cpdu.cbu_rootpri)) << 48) |
638 (((uint64_t)cpdu.cbu_rootaddr[0]) << 40) |
639 (((uint64_t)cpdu.cbu_rootaddr[1]) << 32) |
640 (((uint64_t)cpdu.cbu_rootaddr[2]) << 24) |
641 (((uint64_t)cpdu.cbu_rootaddr[3]) << 16) |
642 (((uint64_t)cpdu.cbu_rootaddr[4]) << 8) |
643 (((uint64_t)cpdu.cbu_rootaddr[5]) << 0);
644
645 cu.cu_bridge_id =
646 (((uint64_t)ntohs(cpdu.cbu_bridgepri)) << 48) |
647 (((uint64_t)cpdu.cbu_bridgeaddr[0]) << 40) |
648 (((uint64_t)cpdu.cbu_bridgeaddr[1]) << 32) |
649 (((uint64_t)cpdu.cbu_bridgeaddr[2]) << 24) |
650 (((uint64_t)cpdu.cbu_bridgeaddr[3]) << 16) |
651 (((uint64_t)cpdu.cbu_bridgeaddr[4]) << 8) |
652 (((uint64_t)cpdu.cbu_bridgeaddr[5]) << 0);
653
654 cu.cu_root_path_cost = ntohl(cpdu.cbu_rootpathcost);
655 cu.cu_message_age = ntohs(cpdu.cbu_messageage);
656 cu.cu_max_age = ntohs(cpdu.cbu_maxage);
657 cu.cu_hello_time = ntohs(cpdu.cbu_hellotime);
658 cu.cu_forward_delay = ntohs(cpdu.cbu_forwarddelay);
659 cu.cu_port_id = ntohs(cpdu.cbu_portid);
660 cu.cu_message_type = cpdu.cbu_bpdutype;
661 cu.cu_topology_change_acknowledgment =
662 (cpdu.cbu_flags & BSTP_FLAG_TCA) ? 1 : 0;
663 cu.cu_topology_change =
664 (cpdu.cbu_flags & BSTP_FLAG_TC) ? 1 : 0;
665 bstp_received_config_bpdu(sc, bif, &cu);
666 break;
667 default:
668 goto out;
669 }
670
671 out:
672 if (m)
673 m_freem(m);
674 return (NULL);
675 }
676
677 void
678 bstp_received_config_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif,
679 struct bstp_config_unit *cu)
680 {
681 int root;
682
683 root = bstp_root_bridge(sc);
684
685 if (bif->bif_state != BSTP_IFSTATE_DISABLED) {
686 if (bstp_supersedes_port_info(sc, bif, cu)) {
687 bstp_record_config_information(sc, bif, cu);
688 bstp_configuration_update(sc);
689 bstp_port_state_selection(sc);
690
691 if ((bstp_root_bridge(sc) == 0) && root) {
692 bstp_timer_stop(&sc->sc_hello_timer);
693
694 if (sc->sc_topology_change_detected) {
695 bstp_timer_stop(
696 &sc->sc_topology_change_timer);
697 bstp_transmit_tcn(sc);
698 bstp_timer_start(&sc->sc_tcn_timer, 0);
699 }
700 }
701
702 if (bif == sc->sc_root_port) {
703 bstp_record_config_timeout_values(sc, cu);
704 bstp_config_bpdu_generation(sc);
705
706 if (cu->cu_topology_change_acknowledgment)
707 bstp_topology_change_acknowledged(sc);
708 }
709 } else if (bstp_designated_port(sc, bif))
710 bstp_transmit_config(sc, bif);
711 }
712 }
713
714 void
715 bstp_received_tcn_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif,
716 struct bstp_tcn_unit *tcn)
717 {
718 if (bif->bif_state != BSTP_IFSTATE_DISABLED &&
719 bstp_designated_port(sc, bif)) {
720 bstp_topology_change_detection(sc);
721 bstp_acknowledge_topology_change(sc, bif);
722 }
723 }
724
725 void
726 bstp_hello_timer_expiry(struct bridge_softc *sc)
727 {
728 bstp_config_bpdu_generation(sc);
729 bstp_timer_start(&sc->sc_hello_timer, 0);
730 }
731
732 void
733 bstp_message_age_timer_expiry(struct bridge_softc *sc,
734 struct bridge_iflist *bif)
735 {
736 int root;
737
738 root = bstp_root_bridge(sc);
739 bstp_become_designated_port(sc, bif);
740 bstp_configuration_update(sc);
741 bstp_port_state_selection(sc);
742
743 if ((bstp_root_bridge(sc)) && (root == 0)) {
744 sc->sc_max_age = sc->sc_bridge_max_age;
745 sc->sc_hello_time = sc->sc_bridge_hello_time;
746 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
747
748 bstp_topology_change_detection(sc);
749 bstp_timer_stop(&sc->sc_tcn_timer);
750 bstp_config_bpdu_generation(sc);
751 bstp_timer_start(&sc->sc_hello_timer, 0);
752 }
753 }
754
755 void
756 bstp_forward_delay_timer_expiry(struct bridge_softc *sc,
757 struct bridge_iflist *bif)
758 {
759 if (bif->bif_state == BSTP_IFSTATE_LISTENING) {
760 bstp_set_port_state(bif, BSTP_IFSTATE_LEARNING);
761 bstp_timer_start(&bif->bif_forward_delay_timer, 0);
762 } else if (bif->bif_state == BSTP_IFSTATE_LEARNING) {
763 bstp_set_port_state(bif, BSTP_IFSTATE_FORWARDING);
764 if (bstp_designated_for_some_port(sc) &&
765 bif->bif_change_detection_enabled)
766 bstp_topology_change_detection(sc);
767 }
768 }
769
770 int
771 bstp_designated_for_some_port(struct bridge_softc *sc)
772 {
773
774 struct bridge_iflist *bif;
775
776 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
777 if ((bif->bif_flags & IFBIF_STP) == 0)
778 continue;
779 if (bif->bif_designated_bridge == sc->sc_bridge_id)
780 return (1);
781 }
782 return (0);
783 }
784
785 void
786 bstp_tcn_timer_expiry(struct bridge_softc *sc)
787 {
788 bstp_transmit_tcn(sc);
789 bstp_timer_start(&sc->sc_tcn_timer, 0);
790 }
791
792 void
793 bstp_topology_change_timer_expiry(struct bridge_softc *sc)
794 {
795 sc->sc_topology_change_detected = 0;
796 sc->sc_topology_change = 0;
797 }
798
799 void
800 bstp_hold_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif)
801 {
802 if (bif->bif_config_pending)
803 bstp_transmit_config(sc, bif);
804 }
805
806 void
807 bstp_initialization(struct bridge_softc *sc)
808 {
809 struct bridge_iflist *bif, *mif;
810
811 mif = NULL;
812 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
813 if ((bif->bif_flags & IFBIF_STP) == 0)
814 continue;
815 if (bif->bif_ifp->if_type != IFT_ETHER)
816 continue;
817 bif->bif_port_id = (bif->bif_priority << 8) |
818 (bif->bif_ifp->if_index & 0xff);
819
820 if (mif == NULL) {
821 mif = bif;
822 continue;
823 }
824 if (memcmp(LLADDR(bif->bif_ifp->if_sadl),
825 LLADDR(mif->bif_ifp->if_sadl), ETHER_ADDR_LEN) < 0) {
826 mif = bif;
827 continue;
828 }
829 }
830 if (mif == NULL) {
831 bstp_stop(sc);
832 return;
833 }
834
835 sc->sc_bridge_id =
836 (((uint64_t)sc->sc_bridge_priority) << 48) |
837 (((uint64_t)LLADDR(mif->bif_ifp->if_sadl)[0]) << 40) |
838 (((uint64_t)LLADDR(mif->bif_ifp->if_sadl)[1]) << 32) |
839 (LLADDR(mif->bif_ifp->if_sadl)[2] << 24) |
840 (LLADDR(mif->bif_ifp->if_sadl)[3] << 16) |
841 (LLADDR(mif->bif_ifp->if_sadl)[4] << 8) |
842 (LLADDR(mif->bif_ifp->if_sadl)[5]);
843
844 sc->sc_designated_root = sc->sc_bridge_id;
845 sc->sc_root_path_cost = 0;
846 sc->sc_root_port = NULL;
847
848 sc->sc_max_age = sc->sc_bridge_max_age;
849 sc->sc_hello_time = sc->sc_bridge_hello_time;
850 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
851 sc->sc_topology_change_detected = 0;
852 sc->sc_topology_change = 0;
853 bstp_timer_stop(&sc->sc_tcn_timer);
854 bstp_timer_stop(&sc->sc_topology_change_timer);
855
856 if (callout_pending(&sc->sc_bstpcallout) == 0)
857 callout_reset(&sc->sc_bstpcallout, hz,
858 bstp_tick, sc);
859
860 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
861 if (bif->bif_flags & IFBIF_STP)
862 bstp_enable_port(sc, bif);
863 else
864 bstp_disable_port(sc, bif);
865 }
866
867 bstp_port_state_selection(sc);
868 bstp_config_bpdu_generation(sc);
869 bstp_timer_start(&sc->sc_hello_timer, 0);
870 }
871
872 void
873 bstp_stop(struct bridge_softc *sc)
874 {
875 struct bridge_iflist *bif;
876
877 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
878 bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED);
879 bstp_timer_stop(&bif->bif_hold_timer);
880 bstp_timer_stop(&bif->bif_message_age_timer);
881 bstp_timer_stop(&bif->bif_forward_delay_timer);
882 }
883
884 callout_stop(&sc->sc_bstpcallout);
885
886 bstp_timer_stop(&sc->sc_topology_change_timer);
887 bstp_timer_stop(&sc->sc_tcn_timer);
888 bstp_timer_stop(&sc->sc_hello_timer);
889
890 }
891
892 void
893 bstp_initialize_port(struct bridge_softc *sc, struct bridge_iflist *bif)
894 {
895 bstp_become_designated_port(sc, bif);
896 bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING);
897 bif->bif_topology_change_acknowledge = 0;
898 bif->bif_config_pending = 0;
899 bif->bif_change_detection_enabled = 1;
900 bstp_timer_stop(&bif->bif_message_age_timer);
901 bstp_timer_stop(&bif->bif_forward_delay_timer);
902 bstp_timer_stop(&bif->bif_hold_timer);
903 }
904
905 void
906 bstp_enable_port(struct bridge_softc *sc, struct bridge_iflist *bif)
907 {
908 bstp_initialize_port(sc, bif);
909 bstp_port_state_selection(sc);
910 }
911
912 void
913 bstp_disable_port(struct bridge_softc *sc, struct bridge_iflist *bif)
914 {
915 int root;
916
917 root = bstp_root_bridge(sc);
918 bstp_become_designated_port(sc, bif);
919 bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED);
920 bif->bif_topology_change_acknowledge = 0;
921 bif->bif_config_pending = 0;
922 bstp_timer_stop(&bif->bif_message_age_timer);
923 bstp_timer_stop(&bif->bif_forward_delay_timer);
924 bstp_configuration_update(sc);
925 bstp_port_state_selection(sc);
926
927 if (bstp_root_bridge(sc) && (root == 0)) {
928 sc->sc_max_age = sc->sc_bridge_max_age;
929 sc->sc_hello_time = sc->sc_bridge_hello_time;
930 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
931
932 bstp_topology_change_detection(sc);
933 bstp_timer_stop(&sc->sc_tcn_timer);
934 bstp_config_bpdu_generation(sc);
935 bstp_timer_start(&sc->sc_hello_timer, 0);
936 }
937 }
938
939 void
940 bstp_set_bridge_priority(struct bridge_softc *sc, uint64_t new_bridge_id)
941 {
942 struct bridge_iflist *bif;
943 int root;
944
945 root = bstp_root_bridge(sc);
946
947 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
948 if ((bif->bif_flags & IFBIF_STP) == 0)
949 continue;
950 if (bstp_designated_port(sc, bif))
951 bif->bif_designated_bridge = new_bridge_id;
952 }
953
954 sc->sc_bridge_id = new_bridge_id;
955
956 bstp_configuration_update(sc);
957 bstp_port_state_selection(sc);
958
959 if (bstp_root_bridge(sc) && (root == 0)) {
960 sc->sc_max_age = sc->sc_bridge_max_age;
961 sc->sc_hello_time = sc->sc_bridge_hello_time;
962 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
963
964 bstp_topology_change_detection(sc);
965 bstp_timer_stop(&sc->sc_tcn_timer);
966 bstp_config_bpdu_generation(sc);
967 bstp_timer_start(&sc->sc_hello_timer, 0);
968 }
969 }
970
971 void
972 bstp_set_port_priority(struct bridge_softc *sc, struct bridge_iflist *bif,
973 uint16_t new_port_id)
974 {
975 if (bstp_designated_port(sc, bif))
976 bif->bif_designated_port = new_port_id;
977
978 bif->bif_port_id = new_port_id;
979
980 if ((sc->sc_bridge_id == bif->bif_designated_bridge) &&
981 (bif->bif_port_id < bif->bif_designated_port)) {
982 bstp_become_designated_port(sc, bif);
983 bstp_port_state_selection(sc);
984 }
985 }
986
987 void
988 bstp_set_path_cost(struct bridge_softc *sc, struct bridge_iflist *bif,
989 uint32_t path_cost)
990 {
991 bif->bif_path_cost = path_cost;
992 bstp_configuration_update(sc);
993 bstp_port_state_selection(sc);
994 }
995
996 void
997 bstp_enable_change_detection(struct bridge_iflist *bif)
998 {
999 bif->bif_change_detection_enabled = 1;
1000 }
1001
1002 void
1003 bstp_disable_change_detection(struct bridge_iflist *bif)
1004 {
1005 bif->bif_change_detection_enabled = 0;
1006 }
1007
1008 void
1009 bstp_ifupdstatus(struct bridge_softc *sc, struct bridge_iflist *bif)
1010 {
1011 struct ifnet *ifp = bif->bif_ifp;
1012
1013 if (ifp->if_flags & IFF_UP) {
1014 switch (ifp->if_link_state) {
1015 case LINK_STATE_UNKNOWN:
1016 /*
1017 * Just enable the port if the link state is
1018 * unknown.
1019 */
1020 if (bif->bif_state == BSTP_IFSTATE_DISABLED)
1021 bstp_enable_port(sc, bif);
1022 break;
1023
1024 case LINK_STATE_UP:
1025 if (bif->bif_state == BSTP_IFSTATE_DISABLED)
1026 bstp_enable_port(sc, bif);
1027 break;
1028
1029 case LINK_STATE_DOWN:
1030 if (bif->bif_state != BSTP_IFSTATE_DISABLED)
1031 bstp_disable_port(sc, bif);
1032 break;
1033 }
1034 return;
1035 }
1036
1037 if (bif->bif_state != BSTP_IFSTATE_DISABLED)
1038 bstp_disable_port(sc, bif);
1039 }
1040
1041 void
1042 bstp_tick(void *arg)
1043 {
1044 struct bridge_softc *sc = arg;
1045 struct bridge_iflist *bif;
1046 int s;
1047
1048 s = splnet();
1049
1050 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1051 if ((bif->bif_flags & IFBIF_STP) == 0)
1052 continue;
1053 /*
1054 * XXX This can cause a lag in "link does away"
1055 * XXX and "spanning tree gets updated". We need
1056 * XXX come sort of callback from the link state
1057 * XXX update code to kick spanning tree.
1058 * XXX --thorpej (at) NetBSD.org
1059 */
1060 bstp_ifupdstatus(sc, bif);
1061 }
1062
1063 if (bstp_timer_expired(&sc->sc_hello_timer, sc->sc_hello_time))
1064 bstp_hello_timer_expiry(sc);
1065
1066 if (bstp_timer_expired(&sc->sc_tcn_timer, sc->sc_bridge_hello_time))
1067 bstp_tcn_timer_expiry(sc);
1068
1069 if (bstp_timer_expired(&sc->sc_topology_change_timer,
1070 sc->sc_topology_change_time))
1071 bstp_topology_change_timer_expiry(sc);
1072
1073 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1074 if ((bif->bif_flags & IFBIF_STP) == 0)
1075 continue;
1076 if (bstp_timer_expired(&bif->bif_message_age_timer,
1077 sc->sc_max_age))
1078 bstp_message_age_timer_expiry(sc, bif);
1079 }
1080
1081 LIST_FOREACH(bif, &sc->sc_iflist, bif_next) {
1082 if ((bif->bif_flags & IFBIF_STP) == 0)
1083 continue;
1084 if (bstp_timer_expired(&bif->bif_forward_delay_timer,
1085 sc->sc_forward_delay))
1086 bstp_forward_delay_timer_expiry(sc, bif);
1087
1088 if (bstp_timer_expired(&bif->bif_hold_timer,
1089 sc->sc_hold_time))
1090 bstp_hold_timer_expiry(sc, bif);
1091 }
1092
1093 if (sc->sc_if.if_flags & IFF_RUNNING)
1094 callout_reset(&sc->sc_bstpcallout, hz, bstp_tick, sc);
1095
1096 splx(s);
1097 }
1098
1099 void
1100 bstp_timer_start(struct bridge_timer *t, uint16_t v)
1101 {
1102 t->value = v;
1103 t->active = 1;
1104 }
1105
1106 void
1107 bstp_timer_stop(struct bridge_timer *t)
1108 {
1109 t->value = 0;
1110 t->active = 0;
1111 }
1112
1113 int
1114 bstp_timer_expired(struct bridge_timer *t, uint16_t v)
1115 {
1116 if (t->active == 0)
1117 return (0);
1118 t->value += BSTP_TICK_VAL;
1119 if (t->value >= v) {
1120 bstp_timer_stop(t);
1121 return (1);
1122 }
1123 return (0);
1124
1125 }
1126