xref: /freebsd/sys/net/bridgestp.c (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
1 /*	$NetBSD: bridgestp.c,v 1.5 2003/11/28 08:56:48 keihan Exp $	*/
2 
3 /*
4  * Copyright (c) 2000 Jason L. Wright (jason@thought.net)
5  * Copyright (c) 2006 Andrew Thompson (thompsa@FreeBSD.org)
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
26  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  *
29  * OpenBSD: bridgestp.c,v 1.5 2001/03/22 03:48:29 jason Exp
30  */
31 
32 /*
33  * Implementation of the spanning tree protocol as defined in
34  * ISO/IEC 802.1D-2004, June 9, 2004.
35  */
36 
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
39 
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/mbuf.h>
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/kernel.h>
46 #include <sys/callout.h>
47 #include <sys/module.h>
48 #include <sys/proc.h>
49 #include <sys/lock.h>
50 #include <sys/mutex.h>
51 #include <sys/taskqueue.h>
52 
53 #include <net/if.h>
54 #include <net/if_var.h>
55 #include <net/if_dl.h>
56 #include <net/if_types.h>
57 #include <net/if_llc.h>
58 #include <net/if_media.h>
59 #include <net/vnet.h>
60 
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/in_var.h>
64 #include <netinet/if_ether.h>
65 #include <net/bridgestp.h>
66 
67 #ifdef	BRIDGESTP_DEBUG
68 #define	DPRINTF(fmt, arg...)	printf("bstp: " fmt, ##arg)
69 #else
70 #define	DPRINTF(fmt, arg...)	(void)0
71 #endif
72 
73 #define	PV2ADDR(pv, eaddr)	do {		\
74 	eaddr[0] = pv >> 40;			\
75 	eaddr[1] = pv >> 32;			\
76 	eaddr[2] = pv >> 24;			\
77 	eaddr[3] = pv >> 16;			\
78 	eaddr[4] = pv >> 8;			\
79 	eaddr[5] = pv >> 0;			\
80 } while (0)
81 
82 #define	INFO_BETTER	1
83 #define	INFO_SAME	0
84 #define	INFO_WORSE	-1
85 
86 const uint8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
87 
88 LIST_HEAD(, bstp_state) bstp_list;
89 static struct mtx	bstp_list_mtx;
90 
91 static void	bstp_transmit(struct bstp_state *, struct bstp_port *);
92 static void	bstp_transmit_bpdu(struct bstp_state *, struct bstp_port *);
93 static void	bstp_transmit_tcn(struct bstp_state *, struct bstp_port *);
94 static void	bstp_decode_bpdu(struct bstp_port *, struct bstp_cbpdu *,
95 		    struct bstp_config_unit *);
96 static void	bstp_send_bpdu(struct bstp_state *, struct bstp_port *,
97 		    struct bstp_cbpdu *);
98 static int	bstp_pdu_flags(struct bstp_port *);
99 static void	bstp_received_stp(struct bstp_state *, struct bstp_port *,
100 		    struct mbuf **, struct bstp_tbpdu *);
101 static void	bstp_received_rstp(struct bstp_state *, struct bstp_port *,
102 		    struct mbuf **, struct bstp_tbpdu *);
103 static void	bstp_received_tcn(struct bstp_state *, struct bstp_port *,
104 		    struct bstp_tcn_unit *);
105 static void	bstp_received_bpdu(struct bstp_state *, struct bstp_port *,
106 		    struct bstp_config_unit *);
107 static int	bstp_pdu_rcvtype(struct bstp_port *, struct bstp_config_unit *);
108 static int	bstp_pdu_bettersame(struct bstp_port *, int);
109 static int	bstp_info_cmp(struct bstp_pri_vector *,
110 		    struct bstp_pri_vector *);
111 static int	bstp_info_superior(struct bstp_pri_vector *,
112 		    struct bstp_pri_vector *);
113 static void	bstp_assign_roles(struct bstp_state *);
114 static void	bstp_update_roles(struct bstp_state *, struct bstp_port *);
115 static void	bstp_update_state(struct bstp_state *, struct bstp_port *);
116 static void	bstp_update_tc(struct bstp_port *);
117 static void	bstp_update_info(struct bstp_port *);
118 static void	bstp_set_other_tcprop(struct bstp_port *);
119 static void	bstp_set_all_reroot(struct bstp_state *);
120 static void	bstp_set_all_sync(struct bstp_state *);
121 static void	bstp_set_port_state(struct bstp_port *, int);
122 static void	bstp_set_port_role(struct bstp_port *, int);
123 static void	bstp_set_port_proto(struct bstp_port *, int);
124 static void	bstp_set_port_tc(struct bstp_port *, int);
125 static void	bstp_set_timer_tc(struct bstp_port *);
126 static void	bstp_set_timer_msgage(struct bstp_port *);
127 static int	bstp_rerooted(struct bstp_state *, struct bstp_port *);
128 static uint32_t	bstp_calc_path_cost(struct bstp_port *);
129 static void	bstp_notify_state(void *, int);
130 static void	bstp_notify_rtage(void *, int);
131 static void	bstp_ifupdstatus(void *, int);
132 static void	bstp_enable_port(struct bstp_state *, struct bstp_port *);
133 static void	bstp_disable_port(struct bstp_state *, struct bstp_port *);
134 static void	bstp_tick(void *);
135 static void	bstp_timer_start(struct bstp_timer *, uint16_t);
136 static void	bstp_timer_stop(struct bstp_timer *);
137 static void	bstp_timer_latch(struct bstp_timer *);
138 static int	bstp_timer_dectest(struct bstp_timer *);
139 static void	bstp_hello_timer_expiry(struct bstp_state *,
140 		    struct bstp_port *);
141 static void	bstp_message_age_expiry(struct bstp_state *,
142 		    struct bstp_port *);
143 static void	bstp_migrate_delay_expiry(struct bstp_state *,
144 		    struct bstp_port *);
145 static void	bstp_edge_delay_expiry(struct bstp_state *,
146 		    struct bstp_port *);
147 static int	bstp_addr_cmp(const uint8_t *, const uint8_t *);
148 static int	bstp_same_bridgeid(uint64_t, uint64_t);
149 static void	bstp_reinit(struct bstp_state *);
150 
151 static void
152 bstp_transmit(struct bstp_state *bs, struct bstp_port *bp)
153 {
154 	if (bs->bs_running == 0)
155 		return;
156 
157 	/*
158 	 * a PDU can only be sent if we have tx quota left and the
159 	 * hello timer is running.
160 	 */
161 	if (bp->bp_hello_timer.active == 0) {
162 		/* Test if it needs to be reset */
163 		bstp_hello_timer_expiry(bs, bp);
164 		return;
165 	}
166 	if (bp->bp_txcount > bs->bs_txholdcount)
167 		/* Ran out of karma */
168 		return;
169 
170 	if (bp->bp_protover == BSTP_PROTO_RSTP) {
171 		bstp_transmit_bpdu(bs, bp);
172 		bp->bp_tc_ack = 0;
173 	} else { /* STP */
174 		switch (bp->bp_role) {
175 			case BSTP_ROLE_DESIGNATED:
176 				bstp_transmit_bpdu(bs, bp);
177 				bp->bp_tc_ack = 0;
178 				break;
179 
180 			case BSTP_ROLE_ROOT:
181 				bstp_transmit_tcn(bs, bp);
182 				break;
183 		}
184 	}
185 	bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
186 	bp->bp_flags &= ~BSTP_PORT_NEWINFO;
187 }
188 
189 static void
190 bstp_transmit_bpdu(struct bstp_state *bs, struct bstp_port *bp)
191 {
192 	struct bstp_cbpdu bpdu;
193 
194 	BSTP_LOCK_ASSERT(bs);
195 
196 	bpdu.cbu_rootpri = htons(bp->bp_desg_pv.pv_root_id >> 48);
197 	PV2ADDR(bp->bp_desg_pv.pv_root_id, bpdu.cbu_rootaddr);
198 
199 	bpdu.cbu_rootpathcost = htonl(bp->bp_desg_pv.pv_cost);
200 
201 	bpdu.cbu_bridgepri = htons(bp->bp_desg_pv.pv_dbridge_id >> 48);
202 	PV2ADDR(bp->bp_desg_pv.pv_dbridge_id, bpdu.cbu_bridgeaddr);
203 
204 	bpdu.cbu_portid = htons(bp->bp_port_id);
205 	bpdu.cbu_messageage = htons(bp->bp_desg_msg_age);
206 	bpdu.cbu_maxage = htons(bp->bp_desg_max_age);
207 	bpdu.cbu_hellotime = htons(bp->bp_desg_htime);
208 	bpdu.cbu_forwarddelay = htons(bp->bp_desg_fdelay);
209 
210 	bpdu.cbu_flags = bstp_pdu_flags(bp);
211 
212 	switch (bp->bp_protover) {
213 		case BSTP_PROTO_STP:
214 			bpdu.cbu_bpdutype = BSTP_MSGTYPE_CFG;
215 			break;
216 
217 		case BSTP_PROTO_RSTP:
218 			bpdu.cbu_bpdutype = BSTP_MSGTYPE_RSTP;
219 			break;
220 	}
221 
222 	bstp_send_bpdu(bs, bp, &bpdu);
223 }
224 
225 static void
226 bstp_transmit_tcn(struct bstp_state *bs, struct bstp_port *bp)
227 {
228 	struct bstp_tbpdu bpdu;
229 	struct ifnet *ifp = bp->bp_ifp;
230 	struct ether_header *eh;
231 	struct mbuf *m;
232 
233 	KASSERT(bp == bs->bs_root_port, ("%s: bad root port\n", __func__));
234 
235 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
236 		return;
237 
238 	m = m_gethdr(M_NOWAIT, MT_DATA);
239 	if (m == NULL)
240 		return;
241 
242 	m->m_pkthdr.rcvif = ifp;
243 	m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
244 	m->m_len = m->m_pkthdr.len;
245 
246 	eh = mtod(m, struct ether_header *);
247 
248 	memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
249 	memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
250 	eh->ether_type = htons(sizeof(bpdu));
251 
252 	bpdu.tbu_ssap = bpdu.tbu_dsap = LLC_8021D_LSAP;
253 	bpdu.tbu_ctl = LLC_UI;
254 	bpdu.tbu_protoid = 0;
255 	bpdu.tbu_protover = 0;
256 	bpdu.tbu_bpdutype = BSTP_MSGTYPE_TCN;
257 
258 	memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu));
259 
260 	bp->bp_txcount++;
261 	ifp->if_transmit(ifp, m);
262 }
263 
264 static void
265 bstp_decode_bpdu(struct bstp_port *bp, struct bstp_cbpdu *cpdu,
266     struct bstp_config_unit *cu)
267 {
268 	int flags;
269 
270 	cu->cu_pv.pv_root_id =
271 	    (((uint64_t)ntohs(cpdu->cbu_rootpri)) << 48) |
272 	    (((uint64_t)cpdu->cbu_rootaddr[0]) << 40) |
273 	    (((uint64_t)cpdu->cbu_rootaddr[1]) << 32) |
274 	    (((uint64_t)cpdu->cbu_rootaddr[2]) << 24) |
275 	    (((uint64_t)cpdu->cbu_rootaddr[3]) << 16) |
276 	    (((uint64_t)cpdu->cbu_rootaddr[4]) << 8) |
277 	    (((uint64_t)cpdu->cbu_rootaddr[5]) << 0);
278 
279 	cu->cu_pv.pv_dbridge_id =
280 	    (((uint64_t)ntohs(cpdu->cbu_bridgepri)) << 48) |
281 	    (((uint64_t)cpdu->cbu_bridgeaddr[0]) << 40) |
282 	    (((uint64_t)cpdu->cbu_bridgeaddr[1]) << 32) |
283 	    (((uint64_t)cpdu->cbu_bridgeaddr[2]) << 24) |
284 	    (((uint64_t)cpdu->cbu_bridgeaddr[3]) << 16) |
285 	    (((uint64_t)cpdu->cbu_bridgeaddr[4]) << 8) |
286 	    (((uint64_t)cpdu->cbu_bridgeaddr[5]) << 0);
287 
288 	cu->cu_pv.pv_cost = ntohl(cpdu->cbu_rootpathcost);
289 	cu->cu_message_age = ntohs(cpdu->cbu_messageage);
290 	cu->cu_max_age = ntohs(cpdu->cbu_maxage);
291 	cu->cu_hello_time = ntohs(cpdu->cbu_hellotime);
292 	cu->cu_forward_delay = ntohs(cpdu->cbu_forwarddelay);
293 	cu->cu_pv.pv_dport_id = ntohs(cpdu->cbu_portid);
294 	cu->cu_pv.pv_port_id = bp->bp_port_id;
295 	cu->cu_message_type = cpdu->cbu_bpdutype;
296 
297 	/* Strip off unused flags in STP mode */
298 	flags = cpdu->cbu_flags;
299 	switch (cpdu->cbu_protover) {
300 		case BSTP_PROTO_STP:
301 			flags &= BSTP_PDU_STPMASK;
302 			/* A STP BPDU explicitly conveys a Designated Port */
303 			cu->cu_role = BSTP_ROLE_DESIGNATED;
304 			break;
305 
306 		case BSTP_PROTO_RSTP:
307 			flags &= BSTP_PDU_RSTPMASK;
308 			break;
309 	}
310 
311 	cu->cu_topology_change_ack =
312 		(flags & BSTP_PDU_F_TCA) ? 1 : 0;
313 	cu->cu_proposal =
314 		(flags & BSTP_PDU_F_P) ? 1 : 0;
315 	cu->cu_agree =
316 		(flags & BSTP_PDU_F_A) ? 1 : 0;
317 	cu->cu_learning =
318 		(flags & BSTP_PDU_F_L) ? 1 : 0;
319 	cu->cu_forwarding =
320 		(flags & BSTP_PDU_F_F) ? 1 : 0;
321 	cu->cu_topology_change =
322 		(flags & BSTP_PDU_F_TC) ? 1 : 0;
323 
324 	switch ((flags & BSTP_PDU_PRMASK) >> BSTP_PDU_PRSHIFT) {
325 		case BSTP_PDU_F_ROOT:
326 			cu->cu_role = BSTP_ROLE_ROOT;
327 			break;
328 		case BSTP_PDU_F_ALT:
329 			cu->cu_role = BSTP_ROLE_ALTERNATE;
330 			break;
331 		case BSTP_PDU_F_DESG:
332 			cu->cu_role = BSTP_ROLE_DESIGNATED;
333 			break;
334 	}
335 }
336 
337 static void
338 bstp_send_bpdu(struct bstp_state *bs, struct bstp_port *bp,
339     struct bstp_cbpdu *bpdu)
340 {
341 	struct ifnet *ifp;
342 	struct mbuf *m;
343 	struct ether_header *eh;
344 
345 	BSTP_LOCK_ASSERT(bs);
346 
347 	ifp = bp->bp_ifp;
348 
349 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
350 		return;
351 
352 	m = m_gethdr(M_NOWAIT, MT_DATA);
353 	if (m == NULL)
354 		return;
355 
356 	eh = mtod(m, struct ether_header *);
357 
358 	bpdu->cbu_ssap = bpdu->cbu_dsap = LLC_8021D_LSAP;
359 	bpdu->cbu_ctl = LLC_UI;
360 	bpdu->cbu_protoid = htons(BSTP_PROTO_ID);
361 
362 	memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
363 	memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
364 
365 	switch (bpdu->cbu_bpdutype) {
366 		case BSTP_MSGTYPE_CFG:
367 			bpdu->cbu_protover = BSTP_PROTO_STP;
368 			m->m_pkthdr.len = sizeof(*eh) + BSTP_BPDU_STP_LEN;
369 			eh->ether_type = htons(BSTP_BPDU_STP_LEN);
370 			memcpy(mtod(m, caddr_t) + sizeof(*eh), bpdu,
371 			    BSTP_BPDU_STP_LEN);
372 			break;
373 
374 		case BSTP_MSGTYPE_RSTP:
375 			bpdu->cbu_protover = BSTP_PROTO_RSTP;
376 			bpdu->cbu_versionlen = htons(0);
377 			m->m_pkthdr.len = sizeof(*eh) + BSTP_BPDU_RSTP_LEN;
378 			eh->ether_type = htons(BSTP_BPDU_RSTP_LEN);
379 			memcpy(mtod(m, caddr_t) + sizeof(*eh), bpdu,
380 			    BSTP_BPDU_RSTP_LEN);
381 			break;
382 
383 		default:
384 			panic("not implemented");
385 	}
386 	m->m_pkthdr.rcvif = ifp;
387 	m->m_len = m->m_pkthdr.len;
388 
389 	bp->bp_txcount++;
390 	ifp->if_transmit(ifp, m);
391 }
392 
393 static int
394 bstp_pdu_flags(struct bstp_port *bp)
395 {
396 	int flags = 0;
397 
398 	if (bp->bp_proposing && bp->bp_state != BSTP_IFSTATE_FORWARDING)
399 		flags |= BSTP_PDU_F_P;
400 
401 	if (bp->bp_agree)
402 		flags |= BSTP_PDU_F_A;
403 
404 	if (bp->bp_tc_timer.active)
405 		flags |= BSTP_PDU_F_TC;
406 
407 	if (bp->bp_tc_ack)
408 		flags |= BSTP_PDU_F_TCA;
409 
410 	switch (bp->bp_state) {
411 		case BSTP_IFSTATE_LEARNING:
412 			flags |= BSTP_PDU_F_L;
413 			break;
414 
415 		case BSTP_IFSTATE_FORWARDING:
416 			flags |= (BSTP_PDU_F_L | BSTP_PDU_F_F);
417 			break;
418 	}
419 
420 	switch (bp->bp_role) {
421 		case BSTP_ROLE_ROOT:
422 			flags |=
423 				(BSTP_PDU_F_ROOT << BSTP_PDU_PRSHIFT);
424 			break;
425 
426 		case BSTP_ROLE_ALTERNATE:
427 		case BSTP_ROLE_BACKUP:	/* fall through */
428 			flags |=
429 				(BSTP_PDU_F_ALT << BSTP_PDU_PRSHIFT);
430 			break;
431 
432 		case BSTP_ROLE_DESIGNATED:
433 			flags |=
434 				(BSTP_PDU_F_DESG << BSTP_PDU_PRSHIFT);
435 			break;
436 	}
437 
438 	/* Strip off unused flags in either mode */
439 	switch (bp->bp_protover) {
440 		case BSTP_PROTO_STP:
441 			flags &= BSTP_PDU_STPMASK;
442 			break;
443 		case BSTP_PROTO_RSTP:
444 			flags &= BSTP_PDU_RSTPMASK;
445 			break;
446 	}
447 	return (flags);
448 }
449 
450 void
451 bstp_input(struct bstp_port *bp, struct ifnet *ifp, struct mbuf *m)
452 {
453 	struct bstp_state *bs = bp->bp_bs;
454 	struct ether_header *eh;
455 	struct bstp_tbpdu tpdu;
456 	uint16_t len;
457 
458 	if (bp->bp_active == 0) {
459 		m_freem(m);
460 		return;
461 	}
462 
463 	BSTP_LOCK(bs);
464 
465 	eh = mtod(m, struct ether_header *);
466 
467 	len = ntohs(eh->ether_type);
468 	if (len < sizeof(tpdu))
469 		goto out;
470 
471 	m_adj(m, ETHER_HDR_LEN);
472 
473 	if (m->m_pkthdr.len > len)
474 		m_adj(m, len - m->m_pkthdr.len);
475 	if (m->m_len < sizeof(tpdu) &&
476 	    (m = m_pullup(m, sizeof(tpdu))) == NULL)
477 		goto out;
478 
479 	memcpy(&tpdu, mtod(m, caddr_t), sizeof(tpdu));
480 
481 	/* basic packet checks */
482 	if (tpdu.tbu_dsap != LLC_8021D_LSAP ||
483 	    tpdu.tbu_ssap != LLC_8021D_LSAP ||
484 	    tpdu.tbu_ctl != LLC_UI)
485 		goto out;
486 	if (tpdu.tbu_protoid != BSTP_PROTO_ID)
487 		goto out;
488 
489 	/*
490 	 * We can treat later versions of the PDU as the same as the maximum
491 	 * version we implement. All additional parameters/flags are ignored.
492 	 */
493 	if (tpdu.tbu_protover > BSTP_PROTO_MAX)
494 		tpdu.tbu_protover = BSTP_PROTO_MAX;
495 
496 	if (tpdu.tbu_protover != bp->bp_protover) {
497 		/*
498 		 * Wait for the migration delay timer to expire before changing
499 		 * protocol version to avoid flip-flops.
500 		 */
501 		if (bp->bp_flags & BSTP_PORT_CANMIGRATE)
502 			bstp_set_port_proto(bp, tpdu.tbu_protover);
503 		else
504 			goto out;
505 	}
506 
507 	/* Clear operedge upon receiving a PDU on the port */
508 	bp->bp_operedge = 0;
509 	bstp_timer_start(&bp->bp_edge_delay_timer,
510 	    BSTP_DEFAULT_MIGRATE_DELAY);
511 
512 	switch (tpdu.tbu_protover) {
513 		case BSTP_PROTO_STP:
514 			bstp_received_stp(bs, bp, &m, &tpdu);
515 			break;
516 
517 		case BSTP_PROTO_RSTP:
518 			bstp_received_rstp(bs, bp, &m, &tpdu);
519 			break;
520 	}
521 out:
522 	BSTP_UNLOCK(bs);
523 	if (m)
524 		m_freem(m);
525 }
526 
527 static void
528 bstp_received_stp(struct bstp_state *bs, struct bstp_port *bp,
529     struct mbuf **mp, struct bstp_tbpdu *tpdu)
530 {
531 	struct bstp_cbpdu cpdu;
532 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
533 	struct bstp_tcn_unit tu;
534 
535 	switch (tpdu->tbu_bpdutype) {
536 	case BSTP_MSGTYPE_TCN:
537 		tu.tu_message_type = tpdu->tbu_bpdutype;
538 		bstp_received_tcn(bs, bp, &tu);
539 		break;
540 	case BSTP_MSGTYPE_CFG:
541 		if ((*mp)->m_len < BSTP_BPDU_STP_LEN &&
542 		    (*mp = m_pullup(*mp, BSTP_BPDU_STP_LEN)) == NULL)
543 			return;
544 		memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_STP_LEN);
545 
546 		bstp_decode_bpdu(bp, &cpdu, cu);
547 		bstp_received_bpdu(bs, bp, cu);
548 		break;
549 	}
550 }
551 
552 static void
553 bstp_received_rstp(struct bstp_state *bs, struct bstp_port *bp,
554     struct mbuf **mp, struct bstp_tbpdu *tpdu)
555 {
556 	struct bstp_cbpdu cpdu;
557 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
558 
559 	if (tpdu->tbu_bpdutype != BSTP_MSGTYPE_RSTP)
560 		return;
561 
562 	if ((*mp)->m_len < BSTP_BPDU_RSTP_LEN &&
563 	    (*mp = m_pullup(*mp, BSTP_BPDU_RSTP_LEN)) == NULL)
564 		return;
565 	memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_RSTP_LEN);
566 
567 	bstp_decode_bpdu(bp, &cpdu, cu);
568 	bstp_received_bpdu(bs, bp, cu);
569 }
570 
571 static void
572 bstp_received_tcn(struct bstp_state *bs, struct bstp_port *bp,
573     struct bstp_tcn_unit *tcn)
574 {
575 	bp->bp_rcvdtcn = 1;
576 	bstp_update_tc(bp);
577 }
578 
579 static void
580 bstp_received_bpdu(struct bstp_state *bs, struct bstp_port *bp,
581     struct bstp_config_unit *cu)
582 {
583 	int type;
584 
585 	BSTP_LOCK_ASSERT(bs);
586 
587 	/* We need to have transitioned to INFO_MINE before proceeding */
588 	switch (bp->bp_infois) {
589 		case BSTP_INFO_DISABLED:
590 		case BSTP_INFO_AGED:
591 			return;
592 	}
593 
594 	type = bstp_pdu_rcvtype(bp, cu);
595 
596 	switch (type) {
597 		case BSTP_PDU_SUPERIOR:
598 			bs->bs_allsynced = 0;
599 			bp->bp_agreed = 0;
600 			bp->bp_proposing = 0;
601 
602 			if (cu->cu_proposal && cu->cu_forwarding == 0)
603 				bp->bp_proposed = 1;
604 			if (cu->cu_topology_change)
605 				bp->bp_rcvdtc = 1;
606 			if (cu->cu_topology_change_ack)
607 				bp->bp_rcvdtca = 1;
608 
609 			if (bp->bp_agree &&
610 			    !bstp_pdu_bettersame(bp, BSTP_INFO_RECEIVED))
611 				bp->bp_agree = 0;
612 
613 			/* copy the received priority and timers to the port */
614 			bp->bp_port_pv = cu->cu_pv;
615 			bp->bp_port_msg_age = cu->cu_message_age;
616 			bp->bp_port_max_age = cu->cu_max_age;
617 			bp->bp_port_fdelay = cu->cu_forward_delay;
618 			bp->bp_port_htime =
619 				(cu->cu_hello_time > BSTP_MIN_HELLO_TIME ?
620 				 cu->cu_hello_time : BSTP_MIN_HELLO_TIME);
621 
622 			/* set expiry for the new info */
623 			bstp_set_timer_msgage(bp);
624 
625 			bp->bp_infois = BSTP_INFO_RECEIVED;
626 			bstp_assign_roles(bs);
627 			break;
628 
629 		case BSTP_PDU_REPEATED:
630 			if (cu->cu_proposal && cu->cu_forwarding == 0)
631 				bp->bp_proposed = 1;
632 			if (cu->cu_topology_change)
633 				bp->bp_rcvdtc = 1;
634 			if (cu->cu_topology_change_ack)
635 				bp->bp_rcvdtca = 1;
636 
637 			/* rearm the age timer */
638 			bstp_set_timer_msgage(bp);
639 			break;
640 
641 		case BSTP_PDU_INFERIOR:
642 			if (cu->cu_learning) {
643 				bp->bp_agreed = 1;
644 				bp->bp_proposing = 0;
645 			}
646 			break;
647 
648 		case BSTP_PDU_INFERIORALT:
649 			/*
650 			 * only point to point links are allowed fast
651 			 * transitions to forwarding.
652 			 */
653 			if (cu->cu_agree && bp->bp_ptp_link) {
654 				bp->bp_agreed = 1;
655 				bp->bp_proposing = 0;
656 			} else
657 				bp->bp_agreed = 0;
658 
659 			if (cu->cu_topology_change)
660 				bp->bp_rcvdtc = 1;
661 			if (cu->cu_topology_change_ack)
662 				bp->bp_rcvdtca = 1;
663 			break;
664 
665 		case BSTP_PDU_OTHER:
666 			return;	/* do nothing */
667 	}
668 	/* update the state machines with the new data */
669 	bstp_update_state(bs, bp);
670 }
671 
672 static int
673 bstp_pdu_rcvtype(struct bstp_port *bp, struct bstp_config_unit *cu)
674 {
675 	int type;
676 
677 	/* default return type */
678 	type = BSTP_PDU_OTHER;
679 
680 	switch (cu->cu_role) {
681 	case BSTP_ROLE_DESIGNATED:
682 		if (bstp_info_superior(&bp->bp_port_pv, &cu->cu_pv))
683 			/* bpdu priority is superior */
684 			type = BSTP_PDU_SUPERIOR;
685 		else if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) ==
686 		    INFO_SAME) {
687 			if (bp->bp_port_msg_age != cu->cu_message_age ||
688 			    bp->bp_port_max_age != cu->cu_max_age ||
689 			    bp->bp_port_fdelay != cu->cu_forward_delay ||
690 			    bp->bp_port_htime != cu->cu_hello_time)
691 				/* bpdu priority is equal and timers differ */
692 				type = BSTP_PDU_SUPERIOR;
693 			else
694 				/* bpdu is equal */
695 				type = BSTP_PDU_REPEATED;
696 		} else
697 			/* bpdu priority is worse */
698 			type = BSTP_PDU_INFERIOR;
699 
700 		break;
701 
702 	case BSTP_ROLE_ROOT:
703 	case BSTP_ROLE_ALTERNATE:
704 	case BSTP_ROLE_BACKUP:
705 		if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) <= INFO_SAME)
706 			/*
707 			 * not a designated port and priority is the same or
708 			 * worse
709 			 */
710 			type = BSTP_PDU_INFERIORALT;
711 		break;
712 	}
713 
714 	return (type);
715 }
716 
717 static int
718 bstp_pdu_bettersame(struct bstp_port *bp, int newinfo)
719 {
720 	if (newinfo == BSTP_INFO_RECEIVED &&
721 	    bp->bp_infois == BSTP_INFO_RECEIVED &&
722 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_msg_cu.cu_pv) >= INFO_SAME)
723 		return (1);
724 
725 	if (newinfo == BSTP_INFO_MINE &&
726 	    bp->bp_infois == BSTP_INFO_MINE &&
727 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_desg_pv) >= INFO_SAME)
728 		return (1);
729 
730 	return (0);
731 }
732 
733 static int
734 bstp_info_cmp(struct bstp_pri_vector *pv,
735     struct bstp_pri_vector *cpv)
736 {
737 	if (cpv->pv_root_id < pv->pv_root_id)
738 		return (INFO_BETTER);
739 	if (cpv->pv_root_id > pv->pv_root_id)
740 		return (INFO_WORSE);
741 
742 	if (cpv->pv_cost < pv->pv_cost)
743 		return (INFO_BETTER);
744 	if (cpv->pv_cost > pv->pv_cost)
745 		return (INFO_WORSE);
746 
747 	if (cpv->pv_dbridge_id < pv->pv_dbridge_id)
748 		return (INFO_BETTER);
749 	if (cpv->pv_dbridge_id > pv->pv_dbridge_id)
750 		return (INFO_WORSE);
751 
752 	if (cpv->pv_dport_id < pv->pv_dport_id)
753 		return (INFO_BETTER);
754 	if (cpv->pv_dport_id > pv->pv_dport_id)
755 		return (INFO_WORSE);
756 
757 	return (INFO_SAME);
758 }
759 
760 /*
761  * This message priority vector is superior to the port priority vector and
762  * will replace it if, and only if, the message priority vector is better than
763  * the port priority vector, or the message has been transmitted from the same
764  * designated bridge and designated port as the port priority vector.
765  */
766 static int
767 bstp_info_superior(struct bstp_pri_vector *pv,
768     struct bstp_pri_vector *cpv)
769 {
770 	if (bstp_info_cmp(pv, cpv) == INFO_BETTER ||
771 	    (bstp_same_bridgeid(pv->pv_dbridge_id, cpv->pv_dbridge_id) &&
772 	    (cpv->pv_dport_id & 0xfff) == (pv->pv_dport_id & 0xfff)))
773 		return (1);
774 	return (0);
775 }
776 
777 static void
778 bstp_assign_roles(struct bstp_state *bs)
779 {
780 	struct bstp_port *bp, *rbp = NULL;
781 	struct bstp_pri_vector pv;
782 
783 	/* default to our priority vector */
784 	bs->bs_root_pv = bs->bs_bridge_pv;
785 	bs->bs_root_msg_age = 0;
786 	bs->bs_root_max_age = bs->bs_bridge_max_age;
787 	bs->bs_root_fdelay = bs->bs_bridge_fdelay;
788 	bs->bs_root_htime = bs->bs_bridge_htime;
789 	bs->bs_root_port = NULL;
790 
791 	/* check if any recieved info supersedes us */
792 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
793 		if (bp->bp_infois != BSTP_INFO_RECEIVED)
794 			continue;
795 
796 		pv = bp->bp_port_pv;
797 		pv.pv_cost += bp->bp_path_cost;
798 
799 		/*
800 		 * The root priority vector is the best of the set comprising
801 		 * the bridge priority vector plus all root path priority
802 		 * vectors whose bridge address is not equal to us.
803 		 */
804 		if (bstp_same_bridgeid(pv.pv_dbridge_id,
805 		    bs->bs_bridge_pv.pv_dbridge_id) == 0 &&
806 		    bstp_info_cmp(&bs->bs_root_pv, &pv) == INFO_BETTER) {
807 			/* the port vector replaces the root */
808 			bs->bs_root_pv = pv;
809 			bs->bs_root_msg_age = bp->bp_port_msg_age +
810 			    BSTP_MESSAGE_AGE_INCR;
811 			bs->bs_root_max_age = bp->bp_port_max_age;
812 			bs->bs_root_fdelay = bp->bp_port_fdelay;
813 			bs->bs_root_htime = bp->bp_port_htime;
814 			rbp = bp;
815 		}
816 	}
817 
818 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
819 		/* calculate the port designated vector */
820 		bp->bp_desg_pv.pv_root_id = bs->bs_root_pv.pv_root_id;
821 		bp->bp_desg_pv.pv_cost = bs->bs_root_pv.pv_cost;
822 		bp->bp_desg_pv.pv_dbridge_id = bs->bs_bridge_pv.pv_dbridge_id;
823 		bp->bp_desg_pv.pv_dport_id = bp->bp_port_id;
824 		bp->bp_desg_pv.pv_port_id = bp->bp_port_id;
825 
826 		/* calculate designated times */
827 		bp->bp_desg_msg_age = bs->bs_root_msg_age;
828 		bp->bp_desg_max_age = bs->bs_root_max_age;
829 		bp->bp_desg_fdelay = bs->bs_root_fdelay;
830 		bp->bp_desg_htime = bs->bs_bridge_htime;
831 
832 
833 		switch (bp->bp_infois) {
834 		case BSTP_INFO_DISABLED:
835 			bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
836 			break;
837 
838 		case BSTP_INFO_AGED:
839 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
840 			bstp_update_info(bp);
841 			break;
842 
843 		case BSTP_INFO_MINE:
844 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
845 			/* update the port info if stale */
846 			if (bstp_info_cmp(&bp->bp_port_pv,
847 			    &bp->bp_desg_pv) != INFO_SAME ||
848 			    (rbp != NULL &&
849 			    (bp->bp_port_msg_age != rbp->bp_port_msg_age ||
850 			    bp->bp_port_max_age != rbp->bp_port_max_age ||
851 			    bp->bp_port_fdelay != rbp->bp_port_fdelay ||
852 			    bp->bp_port_htime != rbp->bp_port_htime)))
853 				bstp_update_info(bp);
854 			break;
855 
856 		case BSTP_INFO_RECEIVED:
857 			if (bp == rbp) {
858 				/*
859 				 * root priority is derived from this
860 				 * port, make it the root port.
861 				 */
862 				bstp_set_port_role(bp, BSTP_ROLE_ROOT);
863 				bs->bs_root_port = bp;
864 			} else if (bstp_info_cmp(&bp->bp_port_pv,
865 				    &bp->bp_desg_pv) == INFO_BETTER) {
866 				/*
867 				 * the port priority is lower than the root
868 				 * port.
869 				 */
870 				bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
871 				bstp_update_info(bp);
872 			} else {
873 				if (bstp_same_bridgeid(
874 				    bp->bp_port_pv.pv_dbridge_id,
875 				    bs->bs_bridge_pv.pv_dbridge_id)) {
876 					/*
877 					 * the designated bridge refers to
878 					 * another port on this bridge.
879 					 */
880 					bstp_set_port_role(bp,
881 					    BSTP_ROLE_BACKUP);
882 				} else {
883 					/*
884 					 * the port is an inferior path to the
885 					 * root bridge.
886 					 */
887 					bstp_set_port_role(bp,
888 					    BSTP_ROLE_ALTERNATE);
889 				}
890 			}
891 			break;
892 		}
893 	}
894 }
895 
896 static void
897 bstp_update_state(struct bstp_state *bs, struct bstp_port *bp)
898 {
899 	struct bstp_port *bp2;
900 	int synced;
901 
902 	BSTP_LOCK_ASSERT(bs);
903 
904 	/* check if all the ports have syncronised again */
905 	if (!bs->bs_allsynced) {
906 		synced = 1;
907 		LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
908 			if (!(bp2->bp_synced ||
909 			     bp2->bp_role == BSTP_ROLE_ROOT)) {
910 				synced = 0;
911 				break;
912 			}
913 		}
914 		bs->bs_allsynced = synced;
915 	}
916 
917 	bstp_update_roles(bs, bp);
918 	bstp_update_tc(bp);
919 }
920 
921 static void
922 bstp_update_roles(struct bstp_state *bs, struct bstp_port *bp)
923 {
924 	switch (bp->bp_role) {
925 	case BSTP_ROLE_DISABLED:
926 		/* Clear any flags if set */
927 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
928 			bp->bp_sync = 0;
929 			bp->bp_synced = 1;
930 			bp->bp_reroot = 0;
931 		}
932 		break;
933 
934 	case BSTP_ROLE_ALTERNATE:
935 	case BSTP_ROLE_BACKUP:
936 		if ((bs->bs_allsynced && !bp->bp_agree) ||
937 		    (bp->bp_proposed && bp->bp_agree)) {
938 			bp->bp_proposed = 0;
939 			bp->bp_agree = 1;
940 			bp->bp_flags |= BSTP_PORT_NEWINFO;
941 			DPRINTF("%s -> ALTERNATE_AGREED\n",
942 			    bp->bp_ifp->if_xname);
943 		}
944 
945 		if (bp->bp_proposed && !bp->bp_agree) {
946 			bstp_set_all_sync(bs);
947 			bp->bp_proposed = 0;
948 			DPRINTF("%s -> ALTERNATE_PROPOSED\n",
949 			    bp->bp_ifp->if_xname);
950 		}
951 
952 		/* Clear any flags if set */
953 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
954 			bp->bp_sync = 0;
955 			bp->bp_synced = 1;
956 			bp->bp_reroot = 0;
957 			DPRINTF("%s -> ALTERNATE_PORT\n", bp->bp_ifp->if_xname);
958 		}
959 		break;
960 
961 	case BSTP_ROLE_ROOT:
962 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING && !bp->bp_reroot) {
963 			bstp_set_all_reroot(bs);
964 			DPRINTF("%s -> ROOT_REROOT\n", bp->bp_ifp->if_xname);
965 		}
966 
967 		if ((bs->bs_allsynced && !bp->bp_agree) ||
968 		    (bp->bp_proposed && bp->bp_agree)) {
969 			bp->bp_proposed = 0;
970 			bp->bp_sync = 0;
971 			bp->bp_agree = 1;
972 			bp->bp_flags |= BSTP_PORT_NEWINFO;
973 			DPRINTF("%s -> ROOT_AGREED\n", bp->bp_ifp->if_xname);
974 		}
975 
976 		if (bp->bp_proposed && !bp->bp_agree) {
977 			bstp_set_all_sync(bs);
978 			bp->bp_proposed = 0;
979 			DPRINTF("%s -> ROOT_PROPOSED\n", bp->bp_ifp->if_xname);
980 		}
981 
982 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
983 		    (bp->bp_forward_delay_timer.active == 0 ||
984 		    (bstp_rerooted(bs, bp) &&
985 		    bp->bp_recent_backup_timer.active == 0 &&
986 		    bp->bp_protover == BSTP_PROTO_RSTP))) {
987 			switch (bp->bp_state) {
988 			case BSTP_IFSTATE_DISCARDING:
989 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
990 				break;
991 			case BSTP_IFSTATE_LEARNING:
992 				bstp_set_port_state(bp,
993 				    BSTP_IFSTATE_FORWARDING);
994 				break;
995 			}
996 		}
997 
998 		if (bp->bp_state == BSTP_IFSTATE_FORWARDING && bp->bp_reroot) {
999 			bp->bp_reroot = 0;
1000 			DPRINTF("%s -> ROOT_REROOTED\n", bp->bp_ifp->if_xname);
1001 		}
1002 		break;
1003 
1004 	case BSTP_ROLE_DESIGNATED:
1005 		if (bp->bp_recent_root_timer.active == 0 && bp->bp_reroot) {
1006 			bp->bp_reroot = 0;
1007 			DPRINTF("%s -> DESIGNATED_RETIRED\n",
1008 			    bp->bp_ifp->if_xname);
1009 		}
1010 
1011 		if ((bp->bp_state == BSTP_IFSTATE_DISCARDING &&
1012 		    !bp->bp_synced) || (bp->bp_agreed && !bp->bp_synced) ||
1013 		    (bp->bp_operedge && !bp->bp_synced) ||
1014 		    (bp->bp_sync && bp->bp_synced)) {
1015 			bstp_timer_stop(&bp->bp_recent_root_timer);
1016 			bp->bp_synced = 1;
1017 			bp->bp_sync = 0;
1018 			DPRINTF("%s -> DESIGNATED_SYNCED\n",
1019 			    bp->bp_ifp->if_xname);
1020 		}
1021 
1022 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1023 		    !bp->bp_agreed && !bp->bp_proposing &&
1024 		    !bp->bp_operedge) {
1025 			bp->bp_proposing = 1;
1026 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1027 			bstp_timer_start(&bp->bp_edge_delay_timer,
1028 			    (bp->bp_ptp_link ? BSTP_DEFAULT_MIGRATE_DELAY :
1029 			     bp->bp_desg_max_age));
1030 			DPRINTF("%s -> DESIGNATED_PROPOSE\n",
1031 			    bp->bp_ifp->if_xname);
1032 		}
1033 
1034 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1035 		    (bp->bp_forward_delay_timer.active == 0 || bp->bp_agreed ||
1036 		    bp->bp_operedge) &&
1037 		    (bp->bp_recent_root_timer.active == 0 || !bp->bp_reroot) &&
1038 		    !bp->bp_sync) {
1039 			if (bp->bp_agreed)
1040 				DPRINTF("%s -> AGREED\n", bp->bp_ifp->if_xname);
1041 			/*
1042 			 * If agreed|operedge then go straight to forwarding,
1043 			 * otherwise follow discard -> learn -> forward.
1044 			 */
1045 			if (bp->bp_agreed || bp->bp_operedge ||
1046 			    bp->bp_state == BSTP_IFSTATE_LEARNING) {
1047 				bstp_set_port_state(bp,
1048 				    BSTP_IFSTATE_FORWARDING);
1049 				bp->bp_agreed = bp->bp_protover;
1050 			} else if (bp->bp_state == BSTP_IFSTATE_DISCARDING)
1051 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
1052 		}
1053 
1054 		if (((bp->bp_sync && !bp->bp_synced) ||
1055 		    (bp->bp_reroot && bp->bp_recent_root_timer.active) ||
1056 		    (bp->bp_flags & BSTP_PORT_DISPUTED)) && !bp->bp_operedge &&
1057 		    bp->bp_state != BSTP_IFSTATE_DISCARDING) {
1058 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1059 			bp->bp_flags &= ~BSTP_PORT_DISPUTED;
1060 			bstp_timer_start(&bp->bp_forward_delay_timer,
1061 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1062 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1063 			DPRINTF("%s -> DESIGNATED_DISCARD\n",
1064 			    bp->bp_ifp->if_xname);
1065 		}
1066 		break;
1067 	}
1068 
1069 	if (bp->bp_flags & BSTP_PORT_NEWINFO)
1070 		bstp_transmit(bs, bp);
1071 }
1072 
1073 static void
1074 bstp_update_tc(struct bstp_port *bp)
1075 {
1076 	switch (bp->bp_tcstate) {
1077 		case BSTP_TCSTATE_ACTIVE:
1078 			if ((bp->bp_role != BSTP_ROLE_DESIGNATED &&
1079 			    bp->bp_role != BSTP_ROLE_ROOT) || bp->bp_operedge)
1080 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1081 
1082 			if (bp->bp_rcvdtcn)
1083 				bstp_set_port_tc(bp, BSTP_TCSTATE_TCN);
1084 			if (bp->bp_rcvdtc)
1085 				bstp_set_port_tc(bp, BSTP_TCSTATE_TC);
1086 
1087 			if (bp->bp_tc_prop && !bp->bp_operedge)
1088 				bstp_set_port_tc(bp, BSTP_TCSTATE_PROPAG);
1089 
1090 			if (bp->bp_rcvdtca)
1091 				bstp_set_port_tc(bp, BSTP_TCSTATE_ACK);
1092 			break;
1093 
1094 		case BSTP_TCSTATE_INACTIVE:
1095 			if ((bp->bp_state == BSTP_IFSTATE_LEARNING ||
1096 			    bp->bp_state == BSTP_IFSTATE_FORWARDING) &&
1097 			    bp->bp_fdbflush == 0)
1098 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1099 			break;
1100 
1101 		case BSTP_TCSTATE_LEARNING:
1102 			if (bp->bp_rcvdtc || bp->bp_rcvdtcn || bp->bp_rcvdtca ||
1103 			    bp->bp_tc_prop)
1104 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1105 			else if (bp->bp_role != BSTP_ROLE_DESIGNATED &&
1106 				 bp->bp_role != BSTP_ROLE_ROOT &&
1107 				 bp->bp_state == BSTP_IFSTATE_DISCARDING)
1108 				bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1109 
1110 			if ((bp->bp_role == BSTP_ROLE_DESIGNATED ||
1111 			    bp->bp_role == BSTP_ROLE_ROOT) &&
1112 			    bp->bp_state == BSTP_IFSTATE_FORWARDING &&
1113 			    !bp->bp_operedge)
1114 				bstp_set_port_tc(bp, BSTP_TCSTATE_DETECTED);
1115 			break;
1116 
1117 		/* these are transient states and go straight back to ACTIVE */
1118 		case BSTP_TCSTATE_DETECTED:
1119 		case BSTP_TCSTATE_TCN:
1120 		case BSTP_TCSTATE_TC:
1121 		case BSTP_TCSTATE_PROPAG:
1122 		case BSTP_TCSTATE_ACK:
1123 			DPRINTF("Invalid TC state for %s\n",
1124 			    bp->bp_ifp->if_xname);
1125 			break;
1126 	}
1127 
1128 }
1129 
1130 static void
1131 bstp_update_info(struct bstp_port *bp)
1132 {
1133 	struct bstp_state *bs = bp->bp_bs;
1134 
1135 	bp->bp_proposing = 0;
1136 	bp->bp_proposed = 0;
1137 
1138 	if (bp->bp_agreed && !bstp_pdu_bettersame(bp, BSTP_INFO_MINE))
1139 		bp->bp_agreed = 0;
1140 
1141 	if (bp->bp_synced && !bp->bp_agreed) {
1142 		bp->bp_synced = 0;
1143 		bs->bs_allsynced = 0;
1144 	}
1145 
1146 	/* copy the designated pv to the port */
1147 	bp->bp_port_pv = bp->bp_desg_pv;
1148 	bp->bp_port_msg_age = bp->bp_desg_msg_age;
1149 	bp->bp_port_max_age = bp->bp_desg_max_age;
1150 	bp->bp_port_fdelay = bp->bp_desg_fdelay;
1151 	bp->bp_port_htime = bp->bp_desg_htime;
1152 	bp->bp_infois = BSTP_INFO_MINE;
1153 
1154 	/* Set transmit flag but do not immediately send */
1155 	bp->bp_flags |= BSTP_PORT_NEWINFO;
1156 }
1157 
1158 /* set tcprop on every port other than the caller */
1159 static void
1160 bstp_set_other_tcprop(struct bstp_port *bp)
1161 {
1162 	struct bstp_state *bs = bp->bp_bs;
1163 	struct bstp_port *bp2;
1164 
1165 	BSTP_LOCK_ASSERT(bs);
1166 
1167 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1168 		if (bp2 == bp)
1169 			continue;
1170 		bp2->bp_tc_prop = 1;
1171 	}
1172 }
1173 
1174 static void
1175 bstp_set_all_reroot(struct bstp_state *bs)
1176 {
1177 	struct bstp_port *bp;
1178 
1179 	BSTP_LOCK_ASSERT(bs);
1180 
1181 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1182 		bp->bp_reroot = 1;
1183 }
1184 
1185 static void
1186 bstp_set_all_sync(struct bstp_state *bs)
1187 {
1188 	struct bstp_port *bp;
1189 
1190 	BSTP_LOCK_ASSERT(bs);
1191 
1192 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1193 		bp->bp_sync = 1;
1194 		bp->bp_synced = 0;	/* Not explicit in spec */
1195 	}
1196 
1197 	bs->bs_allsynced = 0;
1198 }
1199 
1200 static void
1201 bstp_set_port_state(struct bstp_port *bp, int state)
1202 {
1203 	if (bp->bp_state == state)
1204 		return;
1205 
1206 	bp->bp_state = state;
1207 
1208 	switch (bp->bp_state) {
1209 		case BSTP_IFSTATE_DISCARDING:
1210 			DPRINTF("state changed to DISCARDING on %s\n",
1211 			    bp->bp_ifp->if_xname);
1212 			break;
1213 
1214 		case BSTP_IFSTATE_LEARNING:
1215 			DPRINTF("state changed to LEARNING on %s\n",
1216 			    bp->bp_ifp->if_xname);
1217 
1218 			bstp_timer_start(&bp->bp_forward_delay_timer,
1219 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1220 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1221 			break;
1222 
1223 		case BSTP_IFSTATE_FORWARDING:
1224 			DPRINTF("state changed to FORWARDING on %s\n",
1225 			    bp->bp_ifp->if_xname);
1226 
1227 			bstp_timer_stop(&bp->bp_forward_delay_timer);
1228 			/* Record that we enabled forwarding */
1229 			bp->bp_forward_transitions++;
1230 			break;
1231 	}
1232 
1233 	/* notify the parent bridge */
1234 	taskqueue_enqueue(taskqueue_swi, &bp->bp_statetask);
1235 }
1236 
1237 static void
1238 bstp_set_port_role(struct bstp_port *bp, int role)
1239 {
1240 	struct bstp_state *bs = bp->bp_bs;
1241 
1242 	if (bp->bp_role == role)
1243 		return;
1244 
1245 	/* perform pre-change tasks */
1246 	switch (bp->bp_role) {
1247 		case BSTP_ROLE_DISABLED:
1248 			bstp_timer_start(&bp->bp_forward_delay_timer,
1249 			    bp->bp_desg_max_age);
1250 			break;
1251 
1252 		case BSTP_ROLE_BACKUP:
1253 			bstp_timer_start(&bp->bp_recent_backup_timer,
1254 			    bp->bp_desg_htime * 2);
1255 			/* fall through */
1256 		case BSTP_ROLE_ALTERNATE:
1257 			bstp_timer_start(&bp->bp_forward_delay_timer,
1258 			    bp->bp_desg_fdelay);
1259 			bp->bp_sync = 0;
1260 			bp->bp_synced = 1;
1261 			bp->bp_reroot = 0;
1262 			break;
1263 
1264 		case BSTP_ROLE_ROOT:
1265 			bstp_timer_start(&bp->bp_recent_root_timer,
1266 			    BSTP_DEFAULT_FORWARD_DELAY);
1267 			break;
1268 	}
1269 
1270 	bp->bp_role = role;
1271 	/* clear values not carried between roles */
1272 	bp->bp_proposing = 0;
1273 	bs->bs_allsynced = 0;
1274 
1275 	/* initialise the new role */
1276 	switch (bp->bp_role) {
1277 		case BSTP_ROLE_DISABLED:
1278 		case BSTP_ROLE_ALTERNATE:
1279 		case BSTP_ROLE_BACKUP:
1280 			DPRINTF("%s role -> ALT/BACK/DISABLED\n",
1281 			    bp->bp_ifp->if_xname);
1282 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1283 			bstp_timer_stop(&bp->bp_recent_root_timer);
1284 			bstp_timer_latch(&bp->bp_forward_delay_timer);
1285 			bp->bp_sync = 0;
1286 			bp->bp_synced = 1;
1287 			bp->bp_reroot = 0;
1288 			break;
1289 
1290 		case BSTP_ROLE_ROOT:
1291 			DPRINTF("%s role -> ROOT\n",
1292 			    bp->bp_ifp->if_xname);
1293 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1294 			bstp_timer_latch(&bp->bp_recent_root_timer);
1295 			bp->bp_proposing = 0;
1296 			break;
1297 
1298 		case BSTP_ROLE_DESIGNATED:
1299 			DPRINTF("%s role -> DESIGNATED\n",
1300 			    bp->bp_ifp->if_xname);
1301 			bstp_timer_start(&bp->bp_hello_timer,
1302 			    bp->bp_desg_htime);
1303 			bp->bp_agree = 0;
1304 			break;
1305 	}
1306 
1307 	/* let the TC state know that the role changed */
1308 	bstp_update_tc(bp);
1309 }
1310 
1311 static void
1312 bstp_set_port_proto(struct bstp_port *bp, int proto)
1313 {
1314 	struct bstp_state *bs = bp->bp_bs;
1315 
1316 	/* supported protocol versions */
1317 	switch (proto) {
1318 		case BSTP_PROTO_STP:
1319 			/* we can downgrade protocols only */
1320 			bstp_timer_stop(&bp->bp_migrate_delay_timer);
1321 			/* clear unsupported features */
1322 			bp->bp_operedge = 0;
1323 			/* STP compat mode only uses 16 bits of the 32 */
1324 			if (bp->bp_path_cost > 65535)
1325 				bp->bp_path_cost = 65535;
1326 			break;
1327 
1328 		case BSTP_PROTO_RSTP:
1329 			bstp_timer_start(&bp->bp_migrate_delay_timer,
1330 			    bs->bs_migration_delay);
1331 			break;
1332 
1333 		default:
1334 			DPRINTF("Unsupported STP version %d\n", proto);
1335 			return;
1336 	}
1337 
1338 	bp->bp_protover = proto;
1339 	bp->bp_flags &= ~BSTP_PORT_CANMIGRATE;
1340 }
1341 
1342 static void
1343 bstp_set_port_tc(struct bstp_port *bp, int state)
1344 {
1345 	struct bstp_state *bs = bp->bp_bs;
1346 
1347 	bp->bp_tcstate = state;
1348 
1349 	/* initialise the new state */
1350 	switch (bp->bp_tcstate) {
1351 		case BSTP_TCSTATE_ACTIVE:
1352 			DPRINTF("%s -> TC_ACTIVE\n", bp->bp_ifp->if_xname);
1353 			/* nothing to do */
1354 			break;
1355 
1356 		case BSTP_TCSTATE_INACTIVE:
1357 			bstp_timer_stop(&bp->bp_tc_timer);
1358 			/* flush routes on the parent bridge */
1359 			bp->bp_fdbflush = 1;
1360 			taskqueue_enqueue(taskqueue_swi, &bp->bp_rtagetask);
1361 			bp->bp_tc_ack = 0;
1362 			DPRINTF("%s -> TC_INACTIVE\n", bp->bp_ifp->if_xname);
1363 			break;
1364 
1365 		case BSTP_TCSTATE_LEARNING:
1366 			bp->bp_rcvdtc = 0;
1367 			bp->bp_rcvdtcn = 0;
1368 			bp->bp_rcvdtca = 0;
1369 			bp->bp_tc_prop = 0;
1370 			DPRINTF("%s -> TC_LEARNING\n", bp->bp_ifp->if_xname);
1371 			break;
1372 
1373 		case BSTP_TCSTATE_DETECTED:
1374 			bstp_set_timer_tc(bp);
1375 			bstp_set_other_tcprop(bp);
1376 			/* send out notification */
1377 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1378 			bstp_transmit(bs, bp);
1379 			getmicrotime(&bs->bs_last_tc_time);
1380 			DPRINTF("%s -> TC_DETECTED\n", bp->bp_ifp->if_xname);
1381 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1382 			break;
1383 
1384 		case BSTP_TCSTATE_TCN:
1385 			bstp_set_timer_tc(bp);
1386 			DPRINTF("%s -> TC_TCN\n", bp->bp_ifp->if_xname);
1387 			/* fall through */
1388 		case BSTP_TCSTATE_TC:
1389 			bp->bp_rcvdtc = 0;
1390 			bp->bp_rcvdtcn = 0;
1391 			if (bp->bp_role == BSTP_ROLE_DESIGNATED)
1392 				bp->bp_tc_ack = 1;
1393 
1394 			bstp_set_other_tcprop(bp);
1395 			DPRINTF("%s -> TC_TC\n", bp->bp_ifp->if_xname);
1396 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1397 			break;
1398 
1399 		case BSTP_TCSTATE_PROPAG:
1400 			/* flush routes on the parent bridge */
1401 			bp->bp_fdbflush = 1;
1402 			taskqueue_enqueue(taskqueue_swi, &bp->bp_rtagetask);
1403 			bp->bp_tc_prop = 0;
1404 			bstp_set_timer_tc(bp);
1405 			DPRINTF("%s -> TC_PROPAG\n", bp->bp_ifp->if_xname);
1406 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1407 			break;
1408 
1409 		case BSTP_TCSTATE_ACK:
1410 			bstp_timer_stop(&bp->bp_tc_timer);
1411 			bp->bp_rcvdtca = 0;
1412 			DPRINTF("%s -> TC_ACK\n", bp->bp_ifp->if_xname);
1413 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1414 			break;
1415 	}
1416 }
1417 
1418 static void
1419 bstp_set_timer_tc(struct bstp_port *bp)
1420 {
1421 	struct bstp_state *bs = bp->bp_bs;
1422 
1423 	if (bp->bp_tc_timer.active)
1424 		return;
1425 
1426 	switch (bp->bp_protover) {
1427 		case BSTP_PROTO_RSTP:
1428 			bstp_timer_start(&bp->bp_tc_timer,
1429 			    bp->bp_desg_htime + BSTP_TICK_VAL);
1430 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1431 			break;
1432 
1433 		case BSTP_PROTO_STP:
1434 			bstp_timer_start(&bp->bp_tc_timer,
1435 			    bs->bs_root_max_age + bs->bs_root_fdelay);
1436 			break;
1437 	}
1438 }
1439 
1440 static void
1441 bstp_set_timer_msgage(struct bstp_port *bp)
1442 {
1443 	if (bp->bp_port_msg_age + BSTP_MESSAGE_AGE_INCR <=
1444 	    bp->bp_port_max_age) {
1445 		bstp_timer_start(&bp->bp_message_age_timer,
1446 		    bp->bp_port_htime * 3);
1447 	} else
1448 		/* expires immediately */
1449 		bstp_timer_start(&bp->bp_message_age_timer, 0);
1450 }
1451 
1452 static int
1453 bstp_rerooted(struct bstp_state *bs, struct bstp_port *bp)
1454 {
1455 	struct bstp_port *bp2;
1456 	int rr_set = 0;
1457 
1458 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1459 		if (bp2 == bp)
1460 			continue;
1461 		if (bp2->bp_recent_root_timer.active) {
1462 			rr_set = 1;
1463 			break;
1464 		}
1465 	}
1466 	return (!rr_set);
1467 }
1468 
1469 int
1470 bstp_set_htime(struct bstp_state *bs, int t)
1471 {
1472 	/* convert seconds to ticks */
1473 	t *=  BSTP_TICK_VAL;
1474 
1475 	/* value can only be changed in leagacy stp mode */
1476 	if (bs->bs_protover != BSTP_PROTO_STP)
1477 		return (EPERM);
1478 
1479 	if (t < BSTP_MIN_HELLO_TIME || t > BSTP_MAX_HELLO_TIME)
1480 		return (EINVAL);
1481 
1482 	BSTP_LOCK(bs);
1483 	bs->bs_bridge_htime = t;
1484 	bstp_reinit(bs);
1485 	BSTP_UNLOCK(bs);
1486 	return (0);
1487 }
1488 
1489 int
1490 bstp_set_fdelay(struct bstp_state *bs, int t)
1491 {
1492 	/* convert seconds to ticks */
1493 	t *= BSTP_TICK_VAL;
1494 
1495 	if (t < BSTP_MIN_FORWARD_DELAY || t > BSTP_MAX_FORWARD_DELAY)
1496 		return (EINVAL);
1497 
1498 	BSTP_LOCK(bs);
1499 	bs->bs_bridge_fdelay = t;
1500 	bstp_reinit(bs);
1501 	BSTP_UNLOCK(bs);
1502 	return (0);
1503 }
1504 
1505 int
1506 bstp_set_maxage(struct bstp_state *bs, int t)
1507 {
1508 	/* convert seconds to ticks */
1509 	t *= BSTP_TICK_VAL;
1510 
1511 	if (t < BSTP_MIN_MAX_AGE || t > BSTP_MAX_MAX_AGE)
1512 		return (EINVAL);
1513 
1514 	BSTP_LOCK(bs);
1515 	bs->bs_bridge_max_age = t;
1516 	bstp_reinit(bs);
1517 	BSTP_UNLOCK(bs);
1518 	return (0);
1519 }
1520 
1521 int
1522 bstp_set_holdcount(struct bstp_state *bs, int count)
1523 {
1524 	struct bstp_port *bp;
1525 
1526 	if (count < BSTP_MIN_HOLD_COUNT ||
1527 	    count > BSTP_MAX_HOLD_COUNT)
1528 		return (EINVAL);
1529 
1530 	BSTP_LOCK(bs);
1531 	bs->bs_txholdcount = count;
1532 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1533 		bp->bp_txcount = 0;
1534 	BSTP_UNLOCK(bs);
1535 	return (0);
1536 }
1537 
1538 int
1539 bstp_set_protocol(struct bstp_state *bs, int proto)
1540 {
1541 	struct bstp_port *bp;
1542 
1543 	switch (proto) {
1544 		/* Supported protocol versions */
1545 		case BSTP_PROTO_STP:
1546 		case BSTP_PROTO_RSTP:
1547 			break;
1548 
1549 		default:
1550 			return (EINVAL);
1551 	}
1552 
1553 	BSTP_LOCK(bs);
1554 	bs->bs_protover = proto;
1555 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
1556 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1557 		/* reinit state */
1558 		bp->bp_infois = BSTP_INFO_DISABLED;
1559 		bp->bp_txcount = 0;
1560 		bstp_set_port_proto(bp, bs->bs_protover);
1561 		bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
1562 		bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1563 		bstp_timer_stop(&bp->bp_recent_backup_timer);
1564 	}
1565 	bstp_reinit(bs);
1566 	BSTP_UNLOCK(bs);
1567 	return (0);
1568 }
1569 
1570 int
1571 bstp_set_priority(struct bstp_state *bs, int pri)
1572 {
1573 	if (pri < 0 || pri > BSTP_MAX_PRIORITY)
1574 		return (EINVAL);
1575 
1576 	/* Limit to steps of 4096 */
1577 	pri -= pri % 4096;
1578 
1579 	BSTP_LOCK(bs);
1580 	bs->bs_bridge_priority = pri;
1581 	bstp_reinit(bs);
1582 	BSTP_UNLOCK(bs);
1583 	return (0);
1584 }
1585 
1586 int
1587 bstp_set_port_priority(struct bstp_port *bp, int pri)
1588 {
1589 	struct bstp_state *bs = bp->bp_bs;
1590 
1591 	if (pri < 0 || pri > BSTP_MAX_PORT_PRIORITY)
1592 		return (EINVAL);
1593 
1594 	/* Limit to steps of 16 */
1595 	pri -= pri % 16;
1596 
1597 	BSTP_LOCK(bs);
1598 	bp->bp_priority = pri;
1599 	bstp_reinit(bs);
1600 	BSTP_UNLOCK(bs);
1601 	return (0);
1602 }
1603 
1604 int
1605 bstp_set_path_cost(struct bstp_port *bp, uint32_t path_cost)
1606 {
1607 	struct bstp_state *bs = bp->bp_bs;
1608 
1609 	if (path_cost > BSTP_MAX_PATH_COST)
1610 		return (EINVAL);
1611 
1612 	/* STP compat mode only uses 16 bits of the 32 */
1613 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1614 		path_cost = 65535;
1615 
1616 	BSTP_LOCK(bs);
1617 
1618 	if (path_cost == 0) {	/* use auto */
1619 		bp->bp_flags &= ~BSTP_PORT_ADMCOST;
1620 		bp->bp_path_cost = bstp_calc_path_cost(bp);
1621 	} else {
1622 		bp->bp_path_cost = path_cost;
1623 		bp->bp_flags |= BSTP_PORT_ADMCOST;
1624 	}
1625 	bstp_reinit(bs);
1626 	BSTP_UNLOCK(bs);
1627 	return (0);
1628 }
1629 
1630 int
1631 bstp_set_edge(struct bstp_port *bp, int set)
1632 {
1633 	struct bstp_state *bs = bp->bp_bs;
1634 
1635 	BSTP_LOCK(bs);
1636 	if ((bp->bp_operedge = set) == 0)
1637 		bp->bp_flags &= ~BSTP_PORT_ADMEDGE;
1638 	else
1639 		bp->bp_flags |= BSTP_PORT_ADMEDGE;
1640 	BSTP_UNLOCK(bs);
1641 	return (0);
1642 }
1643 
1644 int
1645 bstp_set_autoedge(struct bstp_port *bp, int set)
1646 {
1647 	struct bstp_state *bs = bp->bp_bs;
1648 
1649 	BSTP_LOCK(bs);
1650 	if (set) {
1651 		bp->bp_flags |= BSTP_PORT_AUTOEDGE;
1652 		/* we may be able to transition straight to edge */
1653 		if (bp->bp_edge_delay_timer.active == 0)
1654 			bstp_edge_delay_expiry(bs, bp);
1655 	} else
1656 		bp->bp_flags &= ~BSTP_PORT_AUTOEDGE;
1657 	BSTP_UNLOCK(bs);
1658 	return (0);
1659 }
1660 
1661 int
1662 bstp_set_ptp(struct bstp_port *bp, int set)
1663 {
1664 	struct bstp_state *bs = bp->bp_bs;
1665 
1666 	BSTP_LOCK(bs);
1667 	bp->bp_ptp_link = set;
1668 	BSTP_UNLOCK(bs);
1669 	return (0);
1670 }
1671 
1672 int
1673 bstp_set_autoptp(struct bstp_port *bp, int set)
1674 {
1675 	struct bstp_state *bs = bp->bp_bs;
1676 
1677 	BSTP_LOCK(bs);
1678 	if (set) {
1679 		bp->bp_flags |= BSTP_PORT_AUTOPTP;
1680 		if (bp->bp_role != BSTP_ROLE_DISABLED)
1681 			taskqueue_enqueue(taskqueue_swi, &bp->bp_mediatask);
1682 	} else
1683 		bp->bp_flags &= ~BSTP_PORT_AUTOPTP;
1684 	BSTP_UNLOCK(bs);
1685 	return (0);
1686 }
1687 
1688 /*
1689  * Calculate the path cost according to the link speed.
1690  */
1691 static uint32_t
1692 bstp_calc_path_cost(struct bstp_port *bp)
1693 {
1694 	struct ifnet *ifp = bp->bp_ifp;
1695 	uint32_t path_cost;
1696 
1697 	/* If the priority has been manually set then retain the value */
1698 	if (bp->bp_flags & BSTP_PORT_ADMCOST)
1699 		return bp->bp_path_cost;
1700 
1701 	if (ifp->if_link_state == LINK_STATE_DOWN) {
1702 		/* Recalc when the link comes up again */
1703 		bp->bp_flags |= BSTP_PORT_PNDCOST;
1704 		return (BSTP_DEFAULT_PATH_COST);
1705 	}
1706 
1707 	if (ifp->if_baudrate < 1000)
1708 		return (BSTP_DEFAULT_PATH_COST);
1709 
1710  	/* formula from section 17.14, IEEE Std 802.1D-2004 */
1711 	path_cost = 20000000000ULL / (ifp->if_baudrate / 1000);
1712 
1713 	if (path_cost > BSTP_MAX_PATH_COST)
1714 		path_cost = BSTP_MAX_PATH_COST;
1715 
1716 	/* STP compat mode only uses 16 bits of the 32 */
1717 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1718 		path_cost = 65535;
1719 
1720 	return (path_cost);
1721 }
1722 
1723 /*
1724  * Notify the bridge that a port state has changed, we need to do this from a
1725  * taskqueue to avoid a LOR.
1726  */
1727 static void
1728 bstp_notify_state(void *arg, int pending)
1729 {
1730 	struct bstp_port *bp = (struct bstp_port *)arg;
1731 	struct bstp_state *bs = bp->bp_bs;
1732 
1733 	if (bp->bp_active == 1 && bs->bs_state_cb != NULL)
1734 		(*bs->bs_state_cb)(bp->bp_ifp, bp->bp_state);
1735 }
1736 
1737 /*
1738  * Flush the routes on the bridge port, we need to do this from a
1739  * taskqueue to avoid a LOR.
1740  */
1741 static void
1742 bstp_notify_rtage(void *arg, int pending)
1743 {
1744 	struct bstp_port *bp = (struct bstp_port *)arg;
1745 	struct bstp_state *bs = bp->bp_bs;
1746 	int age = 0;
1747 
1748 	BSTP_LOCK(bs);
1749 	switch (bp->bp_protover) {
1750 		case BSTP_PROTO_STP:
1751 			/* convert to seconds */
1752 			age = bp->bp_desg_fdelay / BSTP_TICK_VAL;
1753 			break;
1754 
1755 		case BSTP_PROTO_RSTP:
1756 			age = 0;
1757 			break;
1758 	}
1759 	BSTP_UNLOCK(bs);
1760 
1761 	if (bp->bp_active == 1 && bs->bs_rtage_cb != NULL)
1762 		(*bs->bs_rtage_cb)(bp->bp_ifp, age);
1763 
1764 	/* flush is complete */
1765 	BSTP_LOCK(bs);
1766 	bp->bp_fdbflush = 0;
1767 	BSTP_UNLOCK(bs);
1768 }
1769 
1770 void
1771 bstp_linkstate(struct bstp_port *bp)
1772 {
1773 	struct bstp_state *bs = bp->bp_bs;
1774 
1775 	if (!bp->bp_active)
1776 		return;
1777 
1778 	bstp_ifupdstatus(bp, 0);
1779 	BSTP_LOCK(bs);
1780 	bstp_update_state(bs, bp);
1781 	BSTP_UNLOCK(bs);
1782 }
1783 
1784 static void
1785 bstp_ifupdstatus(void *arg, int pending)
1786 {
1787 	struct bstp_port *bp = (struct bstp_port *)arg;
1788 	struct bstp_state *bs = bp->bp_bs;
1789 	struct ifnet *ifp = bp->bp_ifp;
1790 	struct ifmediareq ifmr;
1791 	int error, changed;
1792 
1793 	if (!bp->bp_active)
1794 		return;
1795 
1796 	bzero((char *)&ifmr, sizeof(ifmr));
1797 	error = (*ifp->if_ioctl)(ifp, SIOCGIFMEDIA, (caddr_t)&ifmr);
1798 
1799 	BSTP_LOCK(bs);
1800 	changed = 0;
1801 	if ((error == 0) && (ifp->if_flags & IFF_UP)) {
1802 		if (ifmr.ifm_status & IFM_ACTIVE) {
1803 			/* A full-duplex link is assumed to be point to point */
1804 			if (bp->bp_flags & BSTP_PORT_AUTOPTP) {
1805 				int fdx;
1806 
1807 				fdx = ifmr.ifm_active & IFM_FDX ? 1 : 0;
1808 				if (bp->bp_ptp_link ^ fdx) {
1809 					bp->bp_ptp_link = fdx;
1810 					changed = 1;
1811 				}
1812 			}
1813 
1814 			/* Calc the cost if the link was down previously */
1815 			if (bp->bp_flags & BSTP_PORT_PNDCOST) {
1816 				uint32_t cost;
1817 
1818 				cost = bstp_calc_path_cost(bp);
1819 				if (bp->bp_path_cost != cost) {
1820 					bp->bp_path_cost = cost;
1821 					changed = 1;
1822 				}
1823 				bp->bp_flags &= ~BSTP_PORT_PNDCOST;
1824 			}
1825 
1826 			if (bp->bp_role == BSTP_ROLE_DISABLED) {
1827 				bstp_enable_port(bs, bp);
1828 				changed = 1;
1829 			}
1830 		} else {
1831 			if (bp->bp_role != BSTP_ROLE_DISABLED) {
1832 				bstp_disable_port(bs, bp);
1833 				changed = 1;
1834 				if ((bp->bp_flags & BSTP_PORT_ADMEDGE) &&
1835 				    bp->bp_protover == BSTP_PROTO_RSTP)
1836 					bp->bp_operedge = 1;
1837 			}
1838 		}
1839 	} else if (bp->bp_infois != BSTP_INFO_DISABLED) {
1840 		bstp_disable_port(bs, bp);
1841 		changed = 1;
1842 	}
1843 	if (changed)
1844 		bstp_assign_roles(bs);
1845 	BSTP_UNLOCK(bs);
1846 }
1847 
1848 static void
1849 bstp_enable_port(struct bstp_state *bs, struct bstp_port *bp)
1850 {
1851 	bp->bp_infois = BSTP_INFO_AGED;
1852 }
1853 
1854 static void
1855 bstp_disable_port(struct bstp_state *bs, struct bstp_port *bp)
1856 {
1857 	bp->bp_infois = BSTP_INFO_DISABLED;
1858 }
1859 
1860 static void
1861 bstp_tick(void *arg)
1862 {
1863 	struct bstp_state *bs = arg;
1864 	struct bstp_port *bp;
1865 
1866 	BSTP_LOCK_ASSERT(bs);
1867 
1868 	if (bs->bs_running == 0)
1869 		return;
1870 
1871 	CURVNET_SET(bs->bs_vnet);
1872 
1873 	/* poll link events on interfaces that do not support linkstate */
1874 	if (bstp_timer_dectest(&bs->bs_link_timer)) {
1875 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1876 			if (!(bp->bp_ifp->if_capabilities & IFCAP_LINKSTATE))
1877 				taskqueue_enqueue(taskqueue_swi, &bp->bp_mediatask);
1878 		}
1879 		bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
1880 	}
1881 
1882 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1883 		/* no events need to happen for these */
1884 		bstp_timer_dectest(&bp->bp_tc_timer);
1885 		bstp_timer_dectest(&bp->bp_recent_root_timer);
1886 		bstp_timer_dectest(&bp->bp_forward_delay_timer);
1887 		bstp_timer_dectest(&bp->bp_recent_backup_timer);
1888 
1889 		if (bstp_timer_dectest(&bp->bp_hello_timer))
1890 			bstp_hello_timer_expiry(bs, bp);
1891 
1892 		if (bstp_timer_dectest(&bp->bp_message_age_timer))
1893 			bstp_message_age_expiry(bs, bp);
1894 
1895 		if (bstp_timer_dectest(&bp->bp_migrate_delay_timer))
1896 			bstp_migrate_delay_expiry(bs, bp);
1897 
1898 		if (bstp_timer_dectest(&bp->bp_edge_delay_timer))
1899 			bstp_edge_delay_expiry(bs, bp);
1900 
1901 		/* update the various state machines for the port */
1902 		bstp_update_state(bs, bp);
1903 
1904 		if (bp->bp_txcount > 0)
1905 			bp->bp_txcount--;
1906 	}
1907 
1908 	CURVNET_RESTORE();
1909 
1910 	callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
1911 }
1912 
1913 static void
1914 bstp_timer_start(struct bstp_timer *t, uint16_t v)
1915 {
1916 	t->value = v;
1917 	t->active = 1;
1918 	t->latched = 0;
1919 }
1920 
1921 static void
1922 bstp_timer_stop(struct bstp_timer *t)
1923 {
1924 	t->value = 0;
1925 	t->active = 0;
1926 	t->latched = 0;
1927 }
1928 
1929 static void
1930 bstp_timer_latch(struct bstp_timer *t)
1931 {
1932 	t->latched = 1;
1933 	t->active = 1;
1934 }
1935 
1936 static int
1937 bstp_timer_dectest(struct bstp_timer *t)
1938 {
1939 	if (t->active == 0 || t->latched)
1940 		return (0);
1941 	t->value -= BSTP_TICK_VAL;
1942 	if (t->value <= 0) {
1943 		bstp_timer_stop(t);
1944 		return (1);
1945 	}
1946 	return (0);
1947 }
1948 
1949 static void
1950 bstp_hello_timer_expiry(struct bstp_state *bs, struct bstp_port *bp)
1951 {
1952 	if ((bp->bp_flags & BSTP_PORT_NEWINFO) ||
1953 	    bp->bp_role == BSTP_ROLE_DESIGNATED ||
1954 	    (bp->bp_role == BSTP_ROLE_ROOT &&
1955 	     bp->bp_tc_timer.active == 1)) {
1956 		bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
1957 		bp->bp_flags |= BSTP_PORT_NEWINFO;
1958 		bstp_transmit(bs, bp);
1959 	}
1960 }
1961 
1962 static void
1963 bstp_message_age_expiry(struct bstp_state *bs, struct bstp_port *bp)
1964 {
1965 	if (bp->bp_infois == BSTP_INFO_RECEIVED) {
1966 		bp->bp_infois = BSTP_INFO_AGED;
1967 		bstp_assign_roles(bs);
1968 		DPRINTF("aged info on %s\n", bp->bp_ifp->if_xname);
1969 	}
1970 }
1971 
1972 static void
1973 bstp_migrate_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1974 {
1975 	bp->bp_flags |= BSTP_PORT_CANMIGRATE;
1976 }
1977 
1978 static void
1979 bstp_edge_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1980 {
1981 	if ((bp->bp_flags & BSTP_PORT_AUTOEDGE) &&
1982 	    bp->bp_protover == BSTP_PROTO_RSTP && bp->bp_proposing &&
1983 	    bp->bp_role == BSTP_ROLE_DESIGNATED) {
1984 		bp->bp_operedge = 1;
1985 		DPRINTF("%s -> edge port\n", bp->bp_ifp->if_xname);
1986 	}
1987 }
1988 
1989 static int
1990 bstp_addr_cmp(const uint8_t *a, const uint8_t *b)
1991 {
1992 	int i, d;
1993 
1994 	for (i = 0, d = 0; i < ETHER_ADDR_LEN && d == 0; i++) {
1995 		d = ((int)a[i]) - ((int)b[i]);
1996 	}
1997 
1998 	return (d);
1999 }
2000 
2001 /*
2002  * compare the bridge address component of the bridgeid
2003  */
2004 static int
2005 bstp_same_bridgeid(uint64_t id1, uint64_t id2)
2006 {
2007 	u_char addr1[ETHER_ADDR_LEN];
2008 	u_char addr2[ETHER_ADDR_LEN];
2009 
2010 	PV2ADDR(id1, addr1);
2011 	PV2ADDR(id2, addr2);
2012 
2013 	if (bstp_addr_cmp(addr1, addr2) == 0)
2014 		return (1);
2015 
2016 	return (0);
2017 }
2018 
2019 void
2020 bstp_reinit(struct bstp_state *bs)
2021 {
2022 	struct bstp_port *bp;
2023 	struct ifnet *ifp, *mif;
2024 	u_char *e_addr;
2025 	void *bridgeptr;
2026 	static const u_char llzero[ETHER_ADDR_LEN];	/* 00:00:00:00:00:00 */
2027 
2028 	BSTP_LOCK_ASSERT(bs);
2029 
2030 	if (LIST_EMPTY(&bs->bs_bplist))
2031 		goto disablestp;
2032 
2033 	mif = NULL;
2034 	bridgeptr = LIST_FIRST(&bs->bs_bplist)->bp_ifp->if_bridge;
2035 	KASSERT(bridgeptr != NULL, ("Invalid bridge pointer"));
2036 	/*
2037 	 * Search through the Ethernet adapters and find the one with the
2038 	 * lowest value. Make sure the adapter which we take the MAC address
2039 	 * from is part of this bridge, so we can have more than one independent
2040 	 * bridges in the same STP domain.
2041 	 */
2042 	IFNET_RLOCK_NOSLEEP();
2043 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
2044 		if (ifp->if_type != IFT_ETHER)
2045 			continue;	/* Not Ethernet */
2046 
2047 		if (ifp->if_bridge != bridgeptr)
2048 			continue;	/* Not part of our bridge */
2049 
2050 		if (bstp_addr_cmp(IF_LLADDR(ifp), llzero) == 0)
2051 			continue;	/* No mac address set */
2052 
2053 		if (mif == NULL) {
2054 			mif = ifp;
2055 			continue;
2056 		}
2057 		if (bstp_addr_cmp(IF_LLADDR(ifp), IF_LLADDR(mif)) < 0) {
2058 			mif = ifp;
2059 			continue;
2060 		}
2061 	}
2062 	IFNET_RUNLOCK_NOSLEEP();
2063 	if (mif == NULL)
2064 		goto disablestp;
2065 
2066 	e_addr = IF_LLADDR(mif);
2067 	bs->bs_bridge_pv.pv_dbridge_id =
2068 	    (((uint64_t)bs->bs_bridge_priority) << 48) |
2069 	    (((uint64_t)e_addr[0]) << 40) |
2070 	    (((uint64_t)e_addr[1]) << 32) |
2071 	    (((uint64_t)e_addr[2]) << 24) |
2072 	    (((uint64_t)e_addr[3]) << 16) |
2073 	    (((uint64_t)e_addr[4]) << 8) |
2074 	    (((uint64_t)e_addr[5]));
2075 
2076 	bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
2077 	bs->bs_bridge_pv.pv_cost = 0;
2078 	bs->bs_bridge_pv.pv_dport_id = 0;
2079 	bs->bs_bridge_pv.pv_port_id = 0;
2080 
2081 	if (bs->bs_running && callout_pending(&bs->bs_bstpcallout) == 0)
2082 		callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
2083 
2084 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2085 		bp->bp_port_id = (bp->bp_priority << 8) |
2086 		    (bp->bp_ifp->if_index  & 0xfff);
2087 		taskqueue_enqueue(taskqueue_swi, &bp->bp_mediatask);
2088 	}
2089 
2090 	bstp_assign_roles(bs);
2091 	bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
2092 	return;
2093 
2094 disablestp:
2095 	/* Set the bridge and root id (lower bits) to zero */
2096 	bs->bs_bridge_pv.pv_dbridge_id =
2097 	    ((uint64_t)bs->bs_bridge_priority) << 48;
2098 	bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
2099 	bs->bs_root_pv = bs->bs_bridge_pv;
2100 	/* Disable any remaining ports, they will have no MAC address */
2101 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2102 		bp->bp_infois = BSTP_INFO_DISABLED;
2103 		bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2104 	}
2105 	callout_stop(&bs->bs_bstpcallout);
2106 }
2107 
2108 static int
2109 bstp_modevent(module_t mod, int type, void *data)
2110 {
2111 	switch (type) {
2112 	case MOD_LOAD:
2113 		mtx_init(&bstp_list_mtx, "bridgestp list", NULL, MTX_DEF);
2114 		LIST_INIT(&bstp_list);
2115 		break;
2116 	case MOD_UNLOAD:
2117 		mtx_destroy(&bstp_list_mtx);
2118 		break;
2119 	default:
2120 		return (EOPNOTSUPP);
2121 	}
2122 	return (0);
2123 }
2124 
2125 static moduledata_t bstp_mod = {
2126 	"bridgestp",
2127 	bstp_modevent,
2128 	0
2129 };
2130 
2131 DECLARE_MODULE(bridgestp, bstp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
2132 MODULE_VERSION(bridgestp, 1);
2133 
2134 void
2135 bstp_attach(struct bstp_state *bs, struct bstp_cb_ops *cb)
2136 {
2137 	BSTP_LOCK_INIT(bs);
2138 	callout_init_mtx(&bs->bs_bstpcallout, &bs->bs_mtx, 0);
2139 	LIST_INIT(&bs->bs_bplist);
2140 
2141 	bs->bs_bridge_max_age = BSTP_DEFAULT_MAX_AGE;
2142 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
2143 	bs->bs_bridge_fdelay = BSTP_DEFAULT_FORWARD_DELAY;
2144 	bs->bs_bridge_priority = BSTP_DEFAULT_BRIDGE_PRIORITY;
2145 	bs->bs_hold_time = BSTP_DEFAULT_HOLD_TIME;
2146 	bs->bs_migration_delay = BSTP_DEFAULT_MIGRATE_DELAY;
2147 	bs->bs_txholdcount = BSTP_DEFAULT_HOLD_COUNT;
2148 	bs->bs_protover = BSTP_PROTO_RSTP;
2149 	bs->bs_state_cb = cb->bcb_state;
2150 	bs->bs_rtage_cb = cb->bcb_rtage;
2151 	bs->bs_vnet = curvnet;
2152 
2153 	getmicrotime(&bs->bs_last_tc_time);
2154 
2155 	mtx_lock(&bstp_list_mtx);
2156 	LIST_INSERT_HEAD(&bstp_list, bs, bs_list);
2157 	mtx_unlock(&bstp_list_mtx);
2158 }
2159 
2160 void
2161 bstp_detach(struct bstp_state *bs)
2162 {
2163 	KASSERT(LIST_EMPTY(&bs->bs_bplist), ("bstp still active"));
2164 
2165 	mtx_lock(&bstp_list_mtx);
2166 	LIST_REMOVE(bs, bs_list);
2167 	mtx_unlock(&bstp_list_mtx);
2168 	callout_drain(&bs->bs_bstpcallout);
2169 	BSTP_LOCK_DESTROY(bs);
2170 }
2171 
2172 void
2173 bstp_init(struct bstp_state *bs)
2174 {
2175 	BSTP_LOCK(bs);
2176 	callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
2177 	bs->bs_running = 1;
2178 	bstp_reinit(bs);
2179 	BSTP_UNLOCK(bs);
2180 }
2181 
2182 void
2183 bstp_stop(struct bstp_state *bs)
2184 {
2185 	struct bstp_port *bp;
2186 
2187 	BSTP_LOCK(bs);
2188 
2189 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
2190 		bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
2191 
2192 	bs->bs_running = 0;
2193 	callout_stop(&bs->bs_bstpcallout);
2194 	BSTP_UNLOCK(bs);
2195 }
2196 
2197 int
2198 bstp_create(struct bstp_state *bs, struct bstp_port *bp, struct ifnet *ifp)
2199 {
2200 	bzero(bp, sizeof(struct bstp_port));
2201 
2202 	BSTP_LOCK(bs);
2203 	bp->bp_ifp = ifp;
2204 	bp->bp_bs = bs;
2205 	bp->bp_priority = BSTP_DEFAULT_PORT_PRIORITY;
2206 	TASK_INIT(&bp->bp_statetask, 0, bstp_notify_state, bp);
2207 	TASK_INIT(&bp->bp_rtagetask, 0, bstp_notify_rtage, bp);
2208 	TASK_INIT(&bp->bp_mediatask, 0, bstp_ifupdstatus, bp);
2209 
2210 	/* Init state */
2211 	bp->bp_infois = BSTP_INFO_DISABLED;
2212 	bp->bp_flags = BSTP_PORT_AUTOEDGE|BSTP_PORT_AUTOPTP;
2213 	bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
2214 	bstp_set_port_proto(bp, bs->bs_protover);
2215 	bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2216 	bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
2217 	bp->bp_path_cost = bstp_calc_path_cost(bp);
2218 	BSTP_UNLOCK(bs);
2219 	return (0);
2220 }
2221 
2222 int
2223 bstp_enable(struct bstp_port *bp)
2224 {
2225 	struct bstp_state *bs = bp->bp_bs;
2226 	struct ifnet *ifp = bp->bp_ifp;
2227 
2228 	KASSERT(bp->bp_active == 0, ("already a bstp member"));
2229 
2230 	switch (ifp->if_type) {
2231 		case IFT_ETHER:	/* These can do spanning tree. */
2232 			break;
2233 		default:
2234 			/* Nothing else can. */
2235 			return (EINVAL);
2236 	}
2237 
2238 	BSTP_LOCK(bs);
2239 	LIST_INSERT_HEAD(&bs->bs_bplist, bp, bp_next);
2240 	bp->bp_active = 1;
2241 	bp->bp_flags |= BSTP_PORT_NEWINFO;
2242 	bstp_reinit(bs);
2243 	bstp_update_roles(bs, bp);
2244 	BSTP_UNLOCK(bs);
2245 	return (0);
2246 }
2247 
2248 void
2249 bstp_disable(struct bstp_port *bp)
2250 {
2251 	struct bstp_state *bs = bp->bp_bs;
2252 
2253 	KASSERT(bp->bp_active == 1, ("not a bstp member"));
2254 
2255 	BSTP_LOCK(bs);
2256 	bstp_disable_port(bs, bp);
2257 	LIST_REMOVE(bp, bp_next);
2258 	bp->bp_active = 0;
2259 	bstp_reinit(bs);
2260 	BSTP_UNLOCK(bs);
2261 }
2262 
2263 /*
2264  * The bstp_port structure is about to be freed by the parent bridge.
2265  */
2266 void
2267 bstp_destroy(struct bstp_port *bp)
2268 {
2269 	KASSERT(bp->bp_active == 0, ("port is still attached"));
2270 	taskqueue_drain(taskqueue_swi, &bp->bp_statetask);
2271 	taskqueue_drain(taskqueue_swi, &bp->bp_rtagetask);
2272 	taskqueue_drain(taskqueue_swi, &bp->bp_mediatask);
2273 }
2274