xref: /freebsd/sys/net/bridgestp.c (revision 595e514d0df2bac5b813d35f83e32875dbf16a83)
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_dl.h>
55 #include <net/if_types.h>
56 #include <net/if_llc.h>
57 #include <net/if_media.h>
58 #include <net/vnet.h>
59 
60 #include <netinet/in.h>
61 #include <netinet/in_systm.h>
62 #include <netinet/in_var.h>
63 #include <netinet/if_ether.h>
64 #include <net/bridgestp.h>
65 
66 #ifdef	BRIDGESTP_DEBUG
67 #define	DPRINTF(fmt, arg...)	printf("bstp: " fmt, ##arg)
68 #else
69 #define	DPRINTF(fmt, arg...)	(void)0
70 #endif
71 
72 #define	PV2ADDR(pv, eaddr)	do {		\
73 	eaddr[0] = pv >> 40;			\
74 	eaddr[1] = pv >> 32;			\
75 	eaddr[2] = pv >> 24;			\
76 	eaddr[3] = pv >> 16;			\
77 	eaddr[4] = pv >> 8;			\
78 	eaddr[5] = pv >> 0;			\
79 } while (0)
80 
81 #define	INFO_BETTER	1
82 #define	INFO_SAME	0
83 #define	INFO_WORSE	-1
84 
85 const uint8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
86 
87 LIST_HEAD(, bstp_state) bstp_list;
88 static struct mtx	bstp_list_mtx;
89 
90 static void	bstp_transmit(struct bstp_state *, struct bstp_port *);
91 static void	bstp_transmit_bpdu(struct bstp_state *, struct bstp_port *);
92 static void	bstp_transmit_tcn(struct bstp_state *, struct bstp_port *);
93 static void	bstp_decode_bpdu(struct bstp_port *, struct bstp_cbpdu *,
94 		    struct bstp_config_unit *);
95 static void	bstp_send_bpdu(struct bstp_state *, struct bstp_port *,
96 		    struct bstp_cbpdu *);
97 static int	bstp_pdu_flags(struct bstp_port *);
98 static void	bstp_received_stp(struct bstp_state *, struct bstp_port *,
99 		    struct mbuf **, struct bstp_tbpdu *);
100 static void	bstp_received_rstp(struct bstp_state *, struct bstp_port *,
101 		    struct mbuf **, struct bstp_tbpdu *);
102 static void	bstp_received_tcn(struct bstp_state *, struct bstp_port *,
103 		    struct bstp_tcn_unit *);
104 static void	bstp_received_bpdu(struct bstp_state *, struct bstp_port *,
105 		    struct bstp_config_unit *);
106 static int	bstp_pdu_rcvtype(struct bstp_port *, struct bstp_config_unit *);
107 static int	bstp_pdu_bettersame(struct bstp_port *, int);
108 static int	bstp_info_cmp(struct bstp_pri_vector *,
109 		    struct bstp_pri_vector *);
110 static int	bstp_info_superior(struct bstp_pri_vector *,
111 		    struct bstp_pri_vector *);
112 static void	bstp_assign_roles(struct bstp_state *);
113 static void	bstp_update_roles(struct bstp_state *, struct bstp_port *);
114 static void	bstp_update_state(struct bstp_state *, struct bstp_port *);
115 static void	bstp_update_tc(struct bstp_port *);
116 static void	bstp_update_info(struct bstp_port *);
117 static void	bstp_set_other_tcprop(struct bstp_port *);
118 static void	bstp_set_all_reroot(struct bstp_state *);
119 static void	bstp_set_all_sync(struct bstp_state *);
120 static void	bstp_set_port_state(struct bstp_port *, int);
121 static void	bstp_set_port_role(struct bstp_port *, int);
122 static void	bstp_set_port_proto(struct bstp_port *, int);
123 static void	bstp_set_port_tc(struct bstp_port *, int);
124 static void	bstp_set_timer_tc(struct bstp_port *);
125 static void	bstp_set_timer_msgage(struct bstp_port *);
126 static int	bstp_rerooted(struct bstp_state *, struct bstp_port *);
127 static uint32_t	bstp_calc_path_cost(struct bstp_port *);
128 static void	bstp_notify_state(void *, int);
129 static void	bstp_notify_rtage(void *, int);
130 static void	bstp_ifupdstatus(void *, int);
131 static void	bstp_enable_port(struct bstp_state *, struct bstp_port *);
132 static void	bstp_disable_port(struct bstp_state *, struct bstp_port *);
133 static void	bstp_tick(void *);
134 static void	bstp_timer_start(struct bstp_timer *, uint16_t);
135 static void	bstp_timer_stop(struct bstp_timer *);
136 static void	bstp_timer_latch(struct bstp_timer *);
137 static int	bstp_timer_dectest(struct bstp_timer *);
138 static void	bstp_hello_timer_expiry(struct bstp_state *,
139 		    struct bstp_port *);
140 static void	bstp_message_age_expiry(struct bstp_state *,
141 		    struct bstp_port *);
142 static void	bstp_migrate_delay_expiry(struct bstp_state *,
143 		    struct bstp_port *);
144 static void	bstp_edge_delay_expiry(struct bstp_state *,
145 		    struct bstp_port *);
146 static int	bstp_addr_cmp(const uint8_t *, const uint8_t *);
147 static int	bstp_same_bridgeid(uint64_t, uint64_t);
148 static void	bstp_reinit(struct bstp_state *);
149 
150 static void
151 bstp_transmit(struct bstp_state *bs, struct bstp_port *bp)
152 {
153 	if (bs->bs_running == 0)
154 		return;
155 
156 	/*
157 	 * a PDU can only be sent if we have tx quota left and the
158 	 * hello timer is running.
159 	 */
160 	if (bp->bp_hello_timer.active == 0) {
161 		/* Test if it needs to be reset */
162 		bstp_hello_timer_expiry(bs, bp);
163 		return;
164 	}
165 	if (bp->bp_txcount > bs->bs_txholdcount)
166 		/* Ran out of karma */
167 		return;
168 
169 	if (bp->bp_protover == BSTP_PROTO_RSTP) {
170 		bstp_transmit_bpdu(bs, bp);
171 		bp->bp_tc_ack = 0;
172 	} else { /* STP */
173 		switch (bp->bp_role) {
174 			case BSTP_ROLE_DESIGNATED:
175 				bstp_transmit_bpdu(bs, bp);
176 				bp->bp_tc_ack = 0;
177 				break;
178 
179 			case BSTP_ROLE_ROOT:
180 				bstp_transmit_tcn(bs, bp);
181 				break;
182 		}
183 	}
184 	bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
185 	bp->bp_flags &= ~BSTP_PORT_NEWINFO;
186 }
187 
188 static void
189 bstp_transmit_bpdu(struct bstp_state *bs, struct bstp_port *bp)
190 {
191 	struct bstp_cbpdu bpdu;
192 
193 	BSTP_LOCK_ASSERT(bs);
194 
195 	bpdu.cbu_rootpri = htons(bp->bp_desg_pv.pv_root_id >> 48);
196 	PV2ADDR(bp->bp_desg_pv.pv_root_id, bpdu.cbu_rootaddr);
197 
198 	bpdu.cbu_rootpathcost = htonl(bp->bp_desg_pv.pv_cost);
199 
200 	bpdu.cbu_bridgepri = htons(bp->bp_desg_pv.pv_dbridge_id >> 48);
201 	PV2ADDR(bp->bp_desg_pv.pv_dbridge_id, bpdu.cbu_bridgeaddr);
202 
203 	bpdu.cbu_portid = htons(bp->bp_port_id);
204 	bpdu.cbu_messageage = htons(bp->bp_desg_msg_age);
205 	bpdu.cbu_maxage = htons(bp->bp_desg_max_age);
206 	bpdu.cbu_hellotime = htons(bp->bp_desg_htime);
207 	bpdu.cbu_forwarddelay = htons(bp->bp_desg_fdelay);
208 
209 	bpdu.cbu_flags = bstp_pdu_flags(bp);
210 
211 	switch (bp->bp_protover) {
212 		case BSTP_PROTO_STP:
213 			bpdu.cbu_bpdutype = BSTP_MSGTYPE_CFG;
214 			break;
215 
216 		case BSTP_PROTO_RSTP:
217 			bpdu.cbu_bpdutype = BSTP_MSGTYPE_RSTP;
218 			break;
219 	}
220 
221 	bstp_send_bpdu(bs, bp, &bpdu);
222 }
223 
224 static void
225 bstp_transmit_tcn(struct bstp_state *bs, struct bstp_port *bp)
226 {
227 	struct bstp_tbpdu bpdu;
228 	struct ifnet *ifp = bp->bp_ifp;
229 	struct ether_header *eh;
230 	struct mbuf *m;
231 
232 	KASSERT(bp == bs->bs_root_port, ("%s: bad root port\n", __func__));
233 
234 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
235 		return;
236 
237 	m = m_gethdr(M_NOWAIT, MT_DATA);
238 	if (m == NULL)
239 		return;
240 
241 	m->m_pkthdr.rcvif = ifp;
242 	m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
243 	m->m_len = m->m_pkthdr.len;
244 
245 	eh = mtod(m, struct ether_header *);
246 
247 	memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
248 	memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
249 	eh->ether_type = htons(sizeof(bpdu));
250 
251 	bpdu.tbu_ssap = bpdu.tbu_dsap = LLC_8021D_LSAP;
252 	bpdu.tbu_ctl = LLC_UI;
253 	bpdu.tbu_protoid = 0;
254 	bpdu.tbu_protover = 0;
255 	bpdu.tbu_bpdutype = BSTP_MSGTYPE_TCN;
256 
257 	memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu));
258 
259 	bp->bp_txcount++;
260 	ifp->if_transmit(ifp, m);
261 }
262 
263 static void
264 bstp_decode_bpdu(struct bstp_port *bp, struct bstp_cbpdu *cpdu,
265     struct bstp_config_unit *cu)
266 {
267 	int flags;
268 
269 	cu->cu_pv.pv_root_id =
270 	    (((uint64_t)ntohs(cpdu->cbu_rootpri)) << 48) |
271 	    (((uint64_t)cpdu->cbu_rootaddr[0]) << 40) |
272 	    (((uint64_t)cpdu->cbu_rootaddr[1]) << 32) |
273 	    (((uint64_t)cpdu->cbu_rootaddr[2]) << 24) |
274 	    (((uint64_t)cpdu->cbu_rootaddr[3]) << 16) |
275 	    (((uint64_t)cpdu->cbu_rootaddr[4]) << 8) |
276 	    (((uint64_t)cpdu->cbu_rootaddr[5]) << 0);
277 
278 	cu->cu_pv.pv_dbridge_id =
279 	    (((uint64_t)ntohs(cpdu->cbu_bridgepri)) << 48) |
280 	    (((uint64_t)cpdu->cbu_bridgeaddr[0]) << 40) |
281 	    (((uint64_t)cpdu->cbu_bridgeaddr[1]) << 32) |
282 	    (((uint64_t)cpdu->cbu_bridgeaddr[2]) << 24) |
283 	    (((uint64_t)cpdu->cbu_bridgeaddr[3]) << 16) |
284 	    (((uint64_t)cpdu->cbu_bridgeaddr[4]) << 8) |
285 	    (((uint64_t)cpdu->cbu_bridgeaddr[5]) << 0);
286 
287 	cu->cu_pv.pv_cost = ntohl(cpdu->cbu_rootpathcost);
288 	cu->cu_message_age = ntohs(cpdu->cbu_messageage);
289 	cu->cu_max_age = ntohs(cpdu->cbu_maxage);
290 	cu->cu_hello_time = ntohs(cpdu->cbu_hellotime);
291 	cu->cu_forward_delay = ntohs(cpdu->cbu_forwarddelay);
292 	cu->cu_pv.pv_dport_id = ntohs(cpdu->cbu_portid);
293 	cu->cu_pv.pv_port_id = bp->bp_port_id;
294 	cu->cu_message_type = cpdu->cbu_bpdutype;
295 
296 	/* Strip off unused flags in STP mode */
297 	flags = cpdu->cbu_flags;
298 	switch (cpdu->cbu_protover) {
299 		case BSTP_PROTO_STP:
300 			flags &= BSTP_PDU_STPMASK;
301 			/* A STP BPDU explicitly conveys a Designated Port */
302 			cu->cu_role = BSTP_ROLE_DESIGNATED;
303 			break;
304 
305 		case BSTP_PROTO_RSTP:
306 			flags &= BSTP_PDU_RSTPMASK;
307 			break;
308 	}
309 
310 	cu->cu_topology_change_ack =
311 		(flags & BSTP_PDU_F_TCA) ? 1 : 0;
312 	cu->cu_proposal =
313 		(flags & BSTP_PDU_F_P) ? 1 : 0;
314 	cu->cu_agree =
315 		(flags & BSTP_PDU_F_A) ? 1 : 0;
316 	cu->cu_learning =
317 		(flags & BSTP_PDU_F_L) ? 1 : 0;
318 	cu->cu_forwarding =
319 		(flags & BSTP_PDU_F_F) ? 1 : 0;
320 	cu->cu_topology_change =
321 		(flags & BSTP_PDU_F_TC) ? 1 : 0;
322 
323 	switch ((flags & BSTP_PDU_PRMASK) >> BSTP_PDU_PRSHIFT) {
324 		case BSTP_PDU_F_ROOT:
325 			cu->cu_role = BSTP_ROLE_ROOT;
326 			break;
327 		case BSTP_PDU_F_ALT:
328 			cu->cu_role = BSTP_ROLE_ALTERNATE;
329 			break;
330 		case BSTP_PDU_F_DESG:
331 			cu->cu_role = BSTP_ROLE_DESIGNATED;
332 			break;
333 	}
334 }
335 
336 static void
337 bstp_send_bpdu(struct bstp_state *bs, struct bstp_port *bp,
338     struct bstp_cbpdu *bpdu)
339 {
340 	struct ifnet *ifp;
341 	struct mbuf *m;
342 	struct ether_header *eh;
343 
344 	BSTP_LOCK_ASSERT(bs);
345 
346 	ifp = bp->bp_ifp;
347 
348 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
349 		return;
350 
351 	m = m_gethdr(M_NOWAIT, MT_DATA);
352 	if (m == NULL)
353 		return;
354 
355 	eh = mtod(m, struct ether_header *);
356 
357 	bpdu->cbu_ssap = bpdu->cbu_dsap = LLC_8021D_LSAP;
358 	bpdu->cbu_ctl = LLC_UI;
359 	bpdu->cbu_protoid = htons(BSTP_PROTO_ID);
360 
361 	memcpy(eh->ether_shost, IF_LLADDR(ifp), ETHER_ADDR_LEN);
362 	memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
363 
364 	switch (bpdu->cbu_bpdutype) {
365 		case BSTP_MSGTYPE_CFG:
366 			bpdu->cbu_protover = BSTP_PROTO_STP;
367 			m->m_pkthdr.len = sizeof(*eh) + BSTP_BPDU_STP_LEN;
368 			eh->ether_type = htons(BSTP_BPDU_STP_LEN);
369 			memcpy(mtod(m, caddr_t) + sizeof(*eh), bpdu,
370 			    BSTP_BPDU_STP_LEN);
371 			break;
372 
373 		case BSTP_MSGTYPE_RSTP:
374 			bpdu->cbu_protover = BSTP_PROTO_RSTP;
375 			bpdu->cbu_versionlen = htons(0);
376 			m->m_pkthdr.len = sizeof(*eh) + BSTP_BPDU_RSTP_LEN;
377 			eh->ether_type = htons(BSTP_BPDU_RSTP_LEN);
378 			memcpy(mtod(m, caddr_t) + sizeof(*eh), bpdu,
379 			    BSTP_BPDU_RSTP_LEN);
380 			break;
381 
382 		default:
383 			panic("not implemented");
384 	}
385 	m->m_pkthdr.rcvif = ifp;
386 	m->m_len = m->m_pkthdr.len;
387 
388 	bp->bp_txcount++;
389 	ifp->if_transmit(ifp, m);
390 }
391 
392 static int
393 bstp_pdu_flags(struct bstp_port *bp)
394 {
395 	int flags = 0;
396 
397 	if (bp->bp_proposing && bp->bp_state != BSTP_IFSTATE_FORWARDING)
398 		flags |= BSTP_PDU_F_P;
399 
400 	if (bp->bp_agree)
401 		flags |= BSTP_PDU_F_A;
402 
403 	if (bp->bp_tc_timer.active)
404 		flags |= BSTP_PDU_F_TC;
405 
406 	if (bp->bp_tc_ack)
407 		flags |= BSTP_PDU_F_TCA;
408 
409 	switch (bp->bp_state) {
410 		case BSTP_IFSTATE_LEARNING:
411 			flags |= BSTP_PDU_F_L;
412 			break;
413 
414 		case BSTP_IFSTATE_FORWARDING:
415 			flags |= (BSTP_PDU_F_L | BSTP_PDU_F_F);
416 			break;
417 	}
418 
419 	switch (bp->bp_role) {
420 		case BSTP_ROLE_ROOT:
421 			flags |=
422 				(BSTP_PDU_F_ROOT << BSTP_PDU_PRSHIFT);
423 			break;
424 
425 		case BSTP_ROLE_ALTERNATE:
426 		case BSTP_ROLE_BACKUP:	/* fall through */
427 			flags |=
428 				(BSTP_PDU_F_ALT << BSTP_PDU_PRSHIFT);
429 			break;
430 
431 		case BSTP_ROLE_DESIGNATED:
432 			flags |=
433 				(BSTP_PDU_F_DESG << BSTP_PDU_PRSHIFT);
434 			break;
435 	}
436 
437 	/* Strip off unused flags in either mode */
438 	switch (bp->bp_protover) {
439 		case BSTP_PROTO_STP:
440 			flags &= BSTP_PDU_STPMASK;
441 			break;
442 		case BSTP_PROTO_RSTP:
443 			flags &= BSTP_PDU_RSTPMASK;
444 			break;
445 	}
446 	return (flags);
447 }
448 
449 void
450 bstp_input(struct bstp_port *bp, struct ifnet *ifp, struct mbuf *m)
451 {
452 	struct bstp_state *bs = bp->bp_bs;
453 	struct ether_header *eh;
454 	struct bstp_tbpdu tpdu;
455 	uint16_t len;
456 
457 	if (bp->bp_active == 0) {
458 		m_freem(m);
459 		return;
460 	}
461 
462 	BSTP_LOCK(bs);
463 
464 	eh = mtod(m, struct ether_header *);
465 
466 	len = ntohs(eh->ether_type);
467 	if (len < sizeof(tpdu))
468 		goto out;
469 
470 	m_adj(m, ETHER_HDR_LEN);
471 
472 	if (m->m_pkthdr.len > len)
473 		m_adj(m, len - m->m_pkthdr.len);
474 	if (m->m_len < sizeof(tpdu) &&
475 	    (m = m_pullup(m, sizeof(tpdu))) == NULL)
476 		goto out;
477 
478 	memcpy(&tpdu, mtod(m, caddr_t), sizeof(tpdu));
479 
480 	/* basic packet checks */
481 	if (tpdu.tbu_dsap != LLC_8021D_LSAP ||
482 	    tpdu.tbu_ssap != LLC_8021D_LSAP ||
483 	    tpdu.tbu_ctl != LLC_UI)
484 		goto out;
485 	if (tpdu.tbu_protoid != BSTP_PROTO_ID)
486 		goto out;
487 
488 	/*
489 	 * We can treat later versions of the PDU as the same as the maximum
490 	 * version we implement. All additional parameters/flags are ignored.
491 	 */
492 	if (tpdu.tbu_protover > BSTP_PROTO_MAX)
493 		tpdu.tbu_protover = BSTP_PROTO_MAX;
494 
495 	if (tpdu.tbu_protover != bp->bp_protover) {
496 		/*
497 		 * Wait for the migration delay timer to expire before changing
498 		 * protocol version to avoid flip-flops.
499 		 */
500 		if (bp->bp_flags & BSTP_PORT_CANMIGRATE)
501 			bstp_set_port_proto(bp, tpdu.tbu_protover);
502 		else
503 			goto out;
504 	}
505 
506 	/* Clear operedge upon receiving a PDU on the port */
507 	bp->bp_operedge = 0;
508 	bstp_timer_start(&bp->bp_edge_delay_timer,
509 	    BSTP_DEFAULT_MIGRATE_DELAY);
510 
511 	switch (tpdu.tbu_protover) {
512 		case BSTP_PROTO_STP:
513 			bstp_received_stp(bs, bp, &m, &tpdu);
514 			break;
515 
516 		case BSTP_PROTO_RSTP:
517 			bstp_received_rstp(bs, bp, &m, &tpdu);
518 			break;
519 	}
520 out:
521 	BSTP_UNLOCK(bs);
522 	if (m)
523 		m_freem(m);
524 }
525 
526 static void
527 bstp_received_stp(struct bstp_state *bs, struct bstp_port *bp,
528     struct mbuf **mp, struct bstp_tbpdu *tpdu)
529 {
530 	struct bstp_cbpdu cpdu;
531 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
532 	struct bstp_tcn_unit tu;
533 
534 	switch (tpdu->tbu_bpdutype) {
535 	case BSTP_MSGTYPE_TCN:
536 		tu.tu_message_type = tpdu->tbu_bpdutype;
537 		bstp_received_tcn(bs, bp, &tu);
538 		break;
539 	case BSTP_MSGTYPE_CFG:
540 		if ((*mp)->m_len < BSTP_BPDU_STP_LEN &&
541 		    (*mp = m_pullup(*mp, BSTP_BPDU_STP_LEN)) == NULL)
542 			return;
543 		memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_STP_LEN);
544 
545 		bstp_decode_bpdu(bp, &cpdu, cu);
546 		bstp_received_bpdu(bs, bp, cu);
547 		break;
548 	}
549 }
550 
551 static void
552 bstp_received_rstp(struct bstp_state *bs, struct bstp_port *bp,
553     struct mbuf **mp, struct bstp_tbpdu *tpdu)
554 {
555 	struct bstp_cbpdu cpdu;
556 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
557 
558 	if (tpdu->tbu_bpdutype != BSTP_MSGTYPE_RSTP)
559 		return;
560 
561 	if ((*mp)->m_len < BSTP_BPDU_RSTP_LEN &&
562 	    (*mp = m_pullup(*mp, BSTP_BPDU_RSTP_LEN)) == NULL)
563 		return;
564 	memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_RSTP_LEN);
565 
566 	bstp_decode_bpdu(bp, &cpdu, cu);
567 	bstp_received_bpdu(bs, bp, cu);
568 }
569 
570 static void
571 bstp_received_tcn(struct bstp_state *bs, struct bstp_port *bp,
572     struct bstp_tcn_unit *tcn)
573 {
574 	bp->bp_rcvdtcn = 1;
575 	bstp_update_tc(bp);
576 }
577 
578 static void
579 bstp_received_bpdu(struct bstp_state *bs, struct bstp_port *bp,
580     struct bstp_config_unit *cu)
581 {
582 	int type;
583 
584 	BSTP_LOCK_ASSERT(bs);
585 
586 	/* We need to have transitioned to INFO_MINE before proceeding */
587 	switch (bp->bp_infois) {
588 		case BSTP_INFO_DISABLED:
589 		case BSTP_INFO_AGED:
590 			return;
591 	}
592 
593 	type = bstp_pdu_rcvtype(bp, cu);
594 
595 	switch (type) {
596 		case BSTP_PDU_SUPERIOR:
597 			bs->bs_allsynced = 0;
598 			bp->bp_agreed = 0;
599 			bp->bp_proposing = 0;
600 
601 			if (cu->cu_proposal && cu->cu_forwarding == 0)
602 				bp->bp_proposed = 1;
603 			if (cu->cu_topology_change)
604 				bp->bp_rcvdtc = 1;
605 			if (cu->cu_topology_change_ack)
606 				bp->bp_rcvdtca = 1;
607 
608 			if (bp->bp_agree &&
609 			    !bstp_pdu_bettersame(bp, BSTP_INFO_RECEIVED))
610 				bp->bp_agree = 0;
611 
612 			/* copy the received priority and timers to the port */
613 			bp->bp_port_pv = cu->cu_pv;
614 			bp->bp_port_msg_age = cu->cu_message_age;
615 			bp->bp_port_max_age = cu->cu_max_age;
616 			bp->bp_port_fdelay = cu->cu_forward_delay;
617 			bp->bp_port_htime =
618 				(cu->cu_hello_time > BSTP_MIN_HELLO_TIME ?
619 				 cu->cu_hello_time : BSTP_MIN_HELLO_TIME);
620 
621 			/* set expiry for the new info */
622 			bstp_set_timer_msgage(bp);
623 
624 			bp->bp_infois = BSTP_INFO_RECEIVED;
625 			bstp_assign_roles(bs);
626 			break;
627 
628 		case BSTP_PDU_REPEATED:
629 			if (cu->cu_proposal && cu->cu_forwarding == 0)
630 				bp->bp_proposed = 1;
631 			if (cu->cu_topology_change)
632 				bp->bp_rcvdtc = 1;
633 			if (cu->cu_topology_change_ack)
634 				bp->bp_rcvdtca = 1;
635 
636 			/* rearm the age timer */
637 			bstp_set_timer_msgage(bp);
638 			break;
639 
640 		case BSTP_PDU_INFERIOR:
641 			if (cu->cu_learning) {
642 				bp->bp_agreed = 1;
643 				bp->bp_proposing = 0;
644 			}
645 			break;
646 
647 		case BSTP_PDU_INFERIORALT:
648 			/*
649 			 * only point to point links are allowed fast
650 			 * transitions to forwarding.
651 			 */
652 			if (cu->cu_agree && bp->bp_ptp_link) {
653 				bp->bp_agreed = 1;
654 				bp->bp_proposing = 0;
655 			} else
656 				bp->bp_agreed = 0;
657 
658 			if (cu->cu_topology_change)
659 				bp->bp_rcvdtc = 1;
660 			if (cu->cu_topology_change_ack)
661 				bp->bp_rcvdtca = 1;
662 			break;
663 
664 		case BSTP_PDU_OTHER:
665 			return;	/* do nothing */
666 	}
667 	/* update the state machines with the new data */
668 	bstp_update_state(bs, bp);
669 }
670 
671 static int
672 bstp_pdu_rcvtype(struct bstp_port *bp, struct bstp_config_unit *cu)
673 {
674 	int type;
675 
676 	/* default return type */
677 	type = BSTP_PDU_OTHER;
678 
679 	switch (cu->cu_role) {
680 	case BSTP_ROLE_DESIGNATED:
681 		if (bstp_info_superior(&bp->bp_port_pv, &cu->cu_pv))
682 			/* bpdu priority is superior */
683 			type = BSTP_PDU_SUPERIOR;
684 		else if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) ==
685 		    INFO_SAME) {
686 			if (bp->bp_port_msg_age != cu->cu_message_age ||
687 			    bp->bp_port_max_age != cu->cu_max_age ||
688 			    bp->bp_port_fdelay != cu->cu_forward_delay ||
689 			    bp->bp_port_htime != cu->cu_hello_time)
690 				/* bpdu priority is equal and timers differ */
691 				type = BSTP_PDU_SUPERIOR;
692 			else
693 				/* bpdu is equal */
694 				type = BSTP_PDU_REPEATED;
695 		} else
696 			/* bpdu priority is worse */
697 			type = BSTP_PDU_INFERIOR;
698 
699 		break;
700 
701 	case BSTP_ROLE_ROOT:
702 	case BSTP_ROLE_ALTERNATE:
703 	case BSTP_ROLE_BACKUP:
704 		if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) <= INFO_SAME)
705 			/*
706 			 * not a designated port and priority is the same or
707 			 * worse
708 			 */
709 			type = BSTP_PDU_INFERIORALT;
710 		break;
711 	}
712 
713 	return (type);
714 }
715 
716 static int
717 bstp_pdu_bettersame(struct bstp_port *bp, int newinfo)
718 {
719 	if (newinfo == BSTP_INFO_RECEIVED &&
720 	    bp->bp_infois == BSTP_INFO_RECEIVED &&
721 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_msg_cu.cu_pv) >= INFO_SAME)
722 		return (1);
723 
724 	if (newinfo == BSTP_INFO_MINE &&
725 	    bp->bp_infois == BSTP_INFO_MINE &&
726 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_desg_pv) >= INFO_SAME)
727 		return (1);
728 
729 	return (0);
730 }
731 
732 static int
733 bstp_info_cmp(struct bstp_pri_vector *pv,
734     struct bstp_pri_vector *cpv)
735 {
736 	if (cpv->pv_root_id < pv->pv_root_id)
737 		return (INFO_BETTER);
738 	if (cpv->pv_root_id > pv->pv_root_id)
739 		return (INFO_WORSE);
740 
741 	if (cpv->pv_cost < pv->pv_cost)
742 		return (INFO_BETTER);
743 	if (cpv->pv_cost > pv->pv_cost)
744 		return (INFO_WORSE);
745 
746 	if (cpv->pv_dbridge_id < pv->pv_dbridge_id)
747 		return (INFO_BETTER);
748 	if (cpv->pv_dbridge_id > pv->pv_dbridge_id)
749 		return (INFO_WORSE);
750 
751 	if (cpv->pv_dport_id < pv->pv_dport_id)
752 		return (INFO_BETTER);
753 	if (cpv->pv_dport_id > pv->pv_dport_id)
754 		return (INFO_WORSE);
755 
756 	return (INFO_SAME);
757 }
758 
759 /*
760  * This message priority vector is superior to the port priority vector and
761  * will replace it if, and only if, the message priority vector is better than
762  * the port priority vector, or the message has been transmitted from the same
763  * designated bridge and designated port as the port priority vector.
764  */
765 static int
766 bstp_info_superior(struct bstp_pri_vector *pv,
767     struct bstp_pri_vector *cpv)
768 {
769 	if (bstp_info_cmp(pv, cpv) == INFO_BETTER ||
770 	    (bstp_same_bridgeid(pv->pv_dbridge_id, cpv->pv_dbridge_id) &&
771 	    (cpv->pv_dport_id & 0xfff) == (pv->pv_dport_id & 0xfff)))
772 		return (1);
773 	return (0);
774 }
775 
776 static void
777 bstp_assign_roles(struct bstp_state *bs)
778 {
779 	struct bstp_port *bp, *rbp = NULL;
780 	struct bstp_pri_vector pv;
781 
782 	/* default to our priority vector */
783 	bs->bs_root_pv = bs->bs_bridge_pv;
784 	bs->bs_root_msg_age = 0;
785 	bs->bs_root_max_age = bs->bs_bridge_max_age;
786 	bs->bs_root_fdelay = bs->bs_bridge_fdelay;
787 	bs->bs_root_htime = bs->bs_bridge_htime;
788 	bs->bs_root_port = NULL;
789 
790 	/* check if any recieved info supersedes us */
791 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
792 		if (bp->bp_infois != BSTP_INFO_RECEIVED)
793 			continue;
794 
795 		pv = bp->bp_port_pv;
796 		pv.pv_cost += bp->bp_path_cost;
797 
798 		/*
799 		 * The root priority vector is the best of the set comprising
800 		 * the bridge priority vector plus all root path priority
801 		 * vectors whose bridge address is not equal to us.
802 		 */
803 		if (bstp_same_bridgeid(pv.pv_dbridge_id,
804 		    bs->bs_bridge_pv.pv_dbridge_id) == 0 &&
805 		    bstp_info_cmp(&bs->bs_root_pv, &pv) == INFO_BETTER) {
806 			/* the port vector replaces the root */
807 			bs->bs_root_pv = pv;
808 			bs->bs_root_msg_age = bp->bp_port_msg_age +
809 			    BSTP_MESSAGE_AGE_INCR;
810 			bs->bs_root_max_age = bp->bp_port_max_age;
811 			bs->bs_root_fdelay = bp->bp_port_fdelay;
812 			bs->bs_root_htime = bp->bp_port_htime;
813 			rbp = bp;
814 		}
815 	}
816 
817 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
818 		/* calculate the port designated vector */
819 		bp->bp_desg_pv.pv_root_id = bs->bs_root_pv.pv_root_id;
820 		bp->bp_desg_pv.pv_cost = bs->bs_root_pv.pv_cost;
821 		bp->bp_desg_pv.pv_dbridge_id = bs->bs_bridge_pv.pv_dbridge_id;
822 		bp->bp_desg_pv.pv_dport_id = bp->bp_port_id;
823 		bp->bp_desg_pv.pv_port_id = bp->bp_port_id;
824 
825 		/* calculate designated times */
826 		bp->bp_desg_msg_age = bs->bs_root_msg_age;
827 		bp->bp_desg_max_age = bs->bs_root_max_age;
828 		bp->bp_desg_fdelay = bs->bs_root_fdelay;
829 		bp->bp_desg_htime = bs->bs_bridge_htime;
830 
831 
832 		switch (bp->bp_infois) {
833 		case BSTP_INFO_DISABLED:
834 			bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
835 			break;
836 
837 		case BSTP_INFO_AGED:
838 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
839 			bstp_update_info(bp);
840 			break;
841 
842 		case BSTP_INFO_MINE:
843 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
844 			/* update the port info if stale */
845 			if (bstp_info_cmp(&bp->bp_port_pv,
846 			    &bp->bp_desg_pv) != INFO_SAME ||
847 			    (rbp != NULL &&
848 			    (bp->bp_port_msg_age != rbp->bp_port_msg_age ||
849 			    bp->bp_port_max_age != rbp->bp_port_max_age ||
850 			    bp->bp_port_fdelay != rbp->bp_port_fdelay ||
851 			    bp->bp_port_htime != rbp->bp_port_htime)))
852 				bstp_update_info(bp);
853 			break;
854 
855 		case BSTP_INFO_RECEIVED:
856 			if (bp == rbp) {
857 				/*
858 				 * root priority is derived from this
859 				 * port, make it the root port.
860 				 */
861 				bstp_set_port_role(bp, BSTP_ROLE_ROOT);
862 				bs->bs_root_port = bp;
863 			} else if (bstp_info_cmp(&bp->bp_port_pv,
864 				    &bp->bp_desg_pv) == INFO_BETTER) {
865 				/*
866 				 * the port priority is lower than the root
867 				 * port.
868 				 */
869 				bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
870 				bstp_update_info(bp);
871 			} else {
872 				if (bstp_same_bridgeid(
873 				    bp->bp_port_pv.pv_dbridge_id,
874 				    bs->bs_bridge_pv.pv_dbridge_id)) {
875 					/*
876 					 * the designated bridge refers to
877 					 * another port on this bridge.
878 					 */
879 					bstp_set_port_role(bp,
880 					    BSTP_ROLE_BACKUP);
881 				} else {
882 					/*
883 					 * the port is an inferior path to the
884 					 * root bridge.
885 					 */
886 					bstp_set_port_role(bp,
887 					    BSTP_ROLE_ALTERNATE);
888 				}
889 			}
890 			break;
891 		}
892 	}
893 }
894 
895 static void
896 bstp_update_state(struct bstp_state *bs, struct bstp_port *bp)
897 {
898 	struct bstp_port *bp2;
899 	int synced;
900 
901 	BSTP_LOCK_ASSERT(bs);
902 
903 	/* check if all the ports have syncronised again */
904 	if (!bs->bs_allsynced) {
905 		synced = 1;
906 		LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
907 			if (!(bp2->bp_synced ||
908 			     bp2->bp_role == BSTP_ROLE_ROOT)) {
909 				synced = 0;
910 				break;
911 			}
912 		}
913 		bs->bs_allsynced = synced;
914 	}
915 
916 	bstp_update_roles(bs, bp);
917 	bstp_update_tc(bp);
918 }
919 
920 static void
921 bstp_update_roles(struct bstp_state *bs, struct bstp_port *bp)
922 {
923 	switch (bp->bp_role) {
924 	case BSTP_ROLE_DISABLED:
925 		/* Clear any flags if set */
926 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
927 			bp->bp_sync = 0;
928 			bp->bp_synced = 1;
929 			bp->bp_reroot = 0;
930 		}
931 		break;
932 
933 	case BSTP_ROLE_ALTERNATE:
934 	case BSTP_ROLE_BACKUP:
935 		if ((bs->bs_allsynced && !bp->bp_agree) ||
936 		    (bp->bp_proposed && bp->bp_agree)) {
937 			bp->bp_proposed = 0;
938 			bp->bp_agree = 1;
939 			bp->bp_flags |= BSTP_PORT_NEWINFO;
940 			DPRINTF("%s -> ALTERNATE_AGREED\n",
941 			    bp->bp_ifp->if_xname);
942 		}
943 
944 		if (bp->bp_proposed && !bp->bp_agree) {
945 			bstp_set_all_sync(bs);
946 			bp->bp_proposed = 0;
947 			DPRINTF("%s -> ALTERNATE_PROPOSED\n",
948 			    bp->bp_ifp->if_xname);
949 		}
950 
951 		/* Clear any flags if set */
952 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
953 			bp->bp_sync = 0;
954 			bp->bp_synced = 1;
955 			bp->bp_reroot = 0;
956 			DPRINTF("%s -> ALTERNATE_PORT\n", bp->bp_ifp->if_xname);
957 		}
958 		break;
959 
960 	case BSTP_ROLE_ROOT:
961 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING && !bp->bp_reroot) {
962 			bstp_set_all_reroot(bs);
963 			DPRINTF("%s -> ROOT_REROOT\n", bp->bp_ifp->if_xname);
964 		}
965 
966 		if ((bs->bs_allsynced && !bp->bp_agree) ||
967 		    (bp->bp_proposed && bp->bp_agree)) {
968 			bp->bp_proposed = 0;
969 			bp->bp_sync = 0;
970 			bp->bp_agree = 1;
971 			bp->bp_flags |= BSTP_PORT_NEWINFO;
972 			DPRINTF("%s -> ROOT_AGREED\n", bp->bp_ifp->if_xname);
973 		}
974 
975 		if (bp->bp_proposed && !bp->bp_agree) {
976 			bstp_set_all_sync(bs);
977 			bp->bp_proposed = 0;
978 			DPRINTF("%s -> ROOT_PROPOSED\n", bp->bp_ifp->if_xname);
979 		}
980 
981 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
982 		    (bp->bp_forward_delay_timer.active == 0 ||
983 		    (bstp_rerooted(bs, bp) &&
984 		    bp->bp_recent_backup_timer.active == 0 &&
985 		    bp->bp_protover == BSTP_PROTO_RSTP))) {
986 			switch (bp->bp_state) {
987 			case BSTP_IFSTATE_DISCARDING:
988 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
989 				break;
990 			case BSTP_IFSTATE_LEARNING:
991 				bstp_set_port_state(bp,
992 				    BSTP_IFSTATE_FORWARDING);
993 				break;
994 			}
995 		}
996 
997 		if (bp->bp_state == BSTP_IFSTATE_FORWARDING && bp->bp_reroot) {
998 			bp->bp_reroot = 0;
999 			DPRINTF("%s -> ROOT_REROOTED\n", bp->bp_ifp->if_xname);
1000 		}
1001 		break;
1002 
1003 	case BSTP_ROLE_DESIGNATED:
1004 		if (bp->bp_recent_root_timer.active == 0 && bp->bp_reroot) {
1005 			bp->bp_reroot = 0;
1006 			DPRINTF("%s -> DESIGNATED_RETIRED\n",
1007 			    bp->bp_ifp->if_xname);
1008 		}
1009 
1010 		if ((bp->bp_state == BSTP_IFSTATE_DISCARDING &&
1011 		    !bp->bp_synced) || (bp->bp_agreed && !bp->bp_synced) ||
1012 		    (bp->bp_operedge && !bp->bp_synced) ||
1013 		    (bp->bp_sync && bp->bp_synced)) {
1014 			bstp_timer_stop(&bp->bp_recent_root_timer);
1015 			bp->bp_synced = 1;
1016 			bp->bp_sync = 0;
1017 			DPRINTF("%s -> DESIGNATED_SYNCED\n",
1018 			    bp->bp_ifp->if_xname);
1019 		}
1020 
1021 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1022 		    !bp->bp_agreed && !bp->bp_proposing &&
1023 		    !bp->bp_operedge) {
1024 			bp->bp_proposing = 1;
1025 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1026 			bstp_timer_start(&bp->bp_edge_delay_timer,
1027 			    (bp->bp_ptp_link ? BSTP_DEFAULT_MIGRATE_DELAY :
1028 			     bp->bp_desg_max_age));
1029 			DPRINTF("%s -> DESIGNATED_PROPOSE\n",
1030 			    bp->bp_ifp->if_xname);
1031 		}
1032 
1033 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1034 		    (bp->bp_forward_delay_timer.active == 0 || bp->bp_agreed ||
1035 		    bp->bp_operedge) &&
1036 		    (bp->bp_recent_root_timer.active == 0 || !bp->bp_reroot) &&
1037 		    !bp->bp_sync) {
1038 			if (bp->bp_agreed)
1039 				DPRINTF("%s -> AGREED\n", bp->bp_ifp->if_xname);
1040 			/*
1041 			 * If agreed|operedge then go straight to forwarding,
1042 			 * otherwise follow discard -> learn -> forward.
1043 			 */
1044 			if (bp->bp_agreed || bp->bp_operedge ||
1045 			    bp->bp_state == BSTP_IFSTATE_LEARNING) {
1046 				bstp_set_port_state(bp,
1047 				    BSTP_IFSTATE_FORWARDING);
1048 				bp->bp_agreed = bp->bp_protover;
1049 			} else if (bp->bp_state == BSTP_IFSTATE_DISCARDING)
1050 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
1051 		}
1052 
1053 		if (((bp->bp_sync && !bp->bp_synced) ||
1054 		    (bp->bp_reroot && bp->bp_recent_root_timer.active) ||
1055 		    (bp->bp_flags & BSTP_PORT_DISPUTED)) && !bp->bp_operedge &&
1056 		    bp->bp_state != BSTP_IFSTATE_DISCARDING) {
1057 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1058 			bp->bp_flags &= ~BSTP_PORT_DISPUTED;
1059 			bstp_timer_start(&bp->bp_forward_delay_timer,
1060 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1061 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1062 			DPRINTF("%s -> DESIGNATED_DISCARD\n",
1063 			    bp->bp_ifp->if_xname);
1064 		}
1065 		break;
1066 	}
1067 
1068 	if (bp->bp_flags & BSTP_PORT_NEWINFO)
1069 		bstp_transmit(bs, bp);
1070 }
1071 
1072 static void
1073 bstp_update_tc(struct bstp_port *bp)
1074 {
1075 	switch (bp->bp_tcstate) {
1076 		case BSTP_TCSTATE_ACTIVE:
1077 			if ((bp->bp_role != BSTP_ROLE_DESIGNATED &&
1078 			    bp->bp_role != BSTP_ROLE_ROOT) || bp->bp_operedge)
1079 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1080 
1081 			if (bp->bp_rcvdtcn)
1082 				bstp_set_port_tc(bp, BSTP_TCSTATE_TCN);
1083 			if (bp->bp_rcvdtc)
1084 				bstp_set_port_tc(bp, BSTP_TCSTATE_TC);
1085 
1086 			if (bp->bp_tc_prop && !bp->bp_operedge)
1087 				bstp_set_port_tc(bp, BSTP_TCSTATE_PROPAG);
1088 
1089 			if (bp->bp_rcvdtca)
1090 				bstp_set_port_tc(bp, BSTP_TCSTATE_ACK);
1091 			break;
1092 
1093 		case BSTP_TCSTATE_INACTIVE:
1094 			if ((bp->bp_state == BSTP_IFSTATE_LEARNING ||
1095 			    bp->bp_state == BSTP_IFSTATE_FORWARDING) &&
1096 			    bp->bp_fdbflush == 0)
1097 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1098 			break;
1099 
1100 		case BSTP_TCSTATE_LEARNING:
1101 			if (bp->bp_rcvdtc || bp->bp_rcvdtcn || bp->bp_rcvdtca ||
1102 			    bp->bp_tc_prop)
1103 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1104 			else if (bp->bp_role != BSTP_ROLE_DESIGNATED &&
1105 				 bp->bp_role != BSTP_ROLE_ROOT &&
1106 				 bp->bp_state == BSTP_IFSTATE_DISCARDING)
1107 				bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1108 
1109 			if ((bp->bp_role == BSTP_ROLE_DESIGNATED ||
1110 			    bp->bp_role == BSTP_ROLE_ROOT) &&
1111 			    bp->bp_state == BSTP_IFSTATE_FORWARDING &&
1112 			    !bp->bp_operedge)
1113 				bstp_set_port_tc(bp, BSTP_TCSTATE_DETECTED);
1114 			break;
1115 
1116 		/* these are transient states and go straight back to ACTIVE */
1117 		case BSTP_TCSTATE_DETECTED:
1118 		case BSTP_TCSTATE_TCN:
1119 		case BSTP_TCSTATE_TC:
1120 		case BSTP_TCSTATE_PROPAG:
1121 		case BSTP_TCSTATE_ACK:
1122 			DPRINTF("Invalid TC state for %s\n",
1123 			    bp->bp_ifp->if_xname);
1124 			break;
1125 	}
1126 
1127 }
1128 
1129 static void
1130 bstp_update_info(struct bstp_port *bp)
1131 {
1132 	struct bstp_state *bs = bp->bp_bs;
1133 
1134 	bp->bp_proposing = 0;
1135 	bp->bp_proposed = 0;
1136 
1137 	if (bp->bp_agreed && !bstp_pdu_bettersame(bp, BSTP_INFO_MINE))
1138 		bp->bp_agreed = 0;
1139 
1140 	if (bp->bp_synced && !bp->bp_agreed) {
1141 		bp->bp_synced = 0;
1142 		bs->bs_allsynced = 0;
1143 	}
1144 
1145 	/* copy the designated pv to the port */
1146 	bp->bp_port_pv = bp->bp_desg_pv;
1147 	bp->bp_port_msg_age = bp->bp_desg_msg_age;
1148 	bp->bp_port_max_age = bp->bp_desg_max_age;
1149 	bp->bp_port_fdelay = bp->bp_desg_fdelay;
1150 	bp->bp_port_htime = bp->bp_desg_htime;
1151 	bp->bp_infois = BSTP_INFO_MINE;
1152 
1153 	/* Set transmit flag but do not immediately send */
1154 	bp->bp_flags |= BSTP_PORT_NEWINFO;
1155 }
1156 
1157 /* set tcprop on every port other than the caller */
1158 static void
1159 bstp_set_other_tcprop(struct bstp_port *bp)
1160 {
1161 	struct bstp_state *bs = bp->bp_bs;
1162 	struct bstp_port *bp2;
1163 
1164 	BSTP_LOCK_ASSERT(bs);
1165 
1166 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1167 		if (bp2 == bp)
1168 			continue;
1169 		bp2->bp_tc_prop = 1;
1170 	}
1171 }
1172 
1173 static void
1174 bstp_set_all_reroot(struct bstp_state *bs)
1175 {
1176 	struct bstp_port *bp;
1177 
1178 	BSTP_LOCK_ASSERT(bs);
1179 
1180 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1181 		bp->bp_reroot = 1;
1182 }
1183 
1184 static void
1185 bstp_set_all_sync(struct bstp_state *bs)
1186 {
1187 	struct bstp_port *bp;
1188 
1189 	BSTP_LOCK_ASSERT(bs);
1190 
1191 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1192 		bp->bp_sync = 1;
1193 		bp->bp_synced = 0;	/* Not explicit in spec */
1194 	}
1195 
1196 	bs->bs_allsynced = 0;
1197 }
1198 
1199 static void
1200 bstp_set_port_state(struct bstp_port *bp, int state)
1201 {
1202 	if (bp->bp_state == state)
1203 		return;
1204 
1205 	bp->bp_state = state;
1206 
1207 	switch (bp->bp_state) {
1208 		case BSTP_IFSTATE_DISCARDING:
1209 			DPRINTF("state changed to DISCARDING on %s\n",
1210 			    bp->bp_ifp->if_xname);
1211 			break;
1212 
1213 		case BSTP_IFSTATE_LEARNING:
1214 			DPRINTF("state changed to LEARNING on %s\n",
1215 			    bp->bp_ifp->if_xname);
1216 
1217 			bstp_timer_start(&bp->bp_forward_delay_timer,
1218 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1219 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1220 			break;
1221 
1222 		case BSTP_IFSTATE_FORWARDING:
1223 			DPRINTF("state changed to FORWARDING on %s\n",
1224 			    bp->bp_ifp->if_xname);
1225 
1226 			bstp_timer_stop(&bp->bp_forward_delay_timer);
1227 			/* Record that we enabled forwarding */
1228 			bp->bp_forward_transitions++;
1229 			break;
1230 	}
1231 
1232 	/* notify the parent bridge */
1233 	taskqueue_enqueue(taskqueue_swi, &bp->bp_statetask);
1234 }
1235 
1236 static void
1237 bstp_set_port_role(struct bstp_port *bp, int role)
1238 {
1239 	struct bstp_state *bs = bp->bp_bs;
1240 
1241 	if (bp->bp_role == role)
1242 		return;
1243 
1244 	/* perform pre-change tasks */
1245 	switch (bp->bp_role) {
1246 		case BSTP_ROLE_DISABLED:
1247 			bstp_timer_start(&bp->bp_forward_delay_timer,
1248 			    bp->bp_desg_max_age);
1249 			break;
1250 
1251 		case BSTP_ROLE_BACKUP:
1252 			bstp_timer_start(&bp->bp_recent_backup_timer,
1253 			    bp->bp_desg_htime * 2);
1254 			/* fall through */
1255 		case BSTP_ROLE_ALTERNATE:
1256 			bstp_timer_start(&bp->bp_forward_delay_timer,
1257 			    bp->bp_desg_fdelay);
1258 			bp->bp_sync = 0;
1259 			bp->bp_synced = 1;
1260 			bp->bp_reroot = 0;
1261 			break;
1262 
1263 		case BSTP_ROLE_ROOT:
1264 			bstp_timer_start(&bp->bp_recent_root_timer,
1265 			    BSTP_DEFAULT_FORWARD_DELAY);
1266 			break;
1267 	}
1268 
1269 	bp->bp_role = role;
1270 	/* clear values not carried between roles */
1271 	bp->bp_proposing = 0;
1272 	bs->bs_allsynced = 0;
1273 
1274 	/* initialise the new role */
1275 	switch (bp->bp_role) {
1276 		case BSTP_ROLE_DISABLED:
1277 		case BSTP_ROLE_ALTERNATE:
1278 		case BSTP_ROLE_BACKUP:
1279 			DPRINTF("%s role -> ALT/BACK/DISABLED\n",
1280 			    bp->bp_ifp->if_xname);
1281 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1282 			bstp_timer_stop(&bp->bp_recent_root_timer);
1283 			bstp_timer_latch(&bp->bp_forward_delay_timer);
1284 			bp->bp_sync = 0;
1285 			bp->bp_synced = 1;
1286 			bp->bp_reroot = 0;
1287 			break;
1288 
1289 		case BSTP_ROLE_ROOT:
1290 			DPRINTF("%s role -> ROOT\n",
1291 			    bp->bp_ifp->if_xname);
1292 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1293 			bstp_timer_latch(&bp->bp_recent_root_timer);
1294 			bp->bp_proposing = 0;
1295 			break;
1296 
1297 		case BSTP_ROLE_DESIGNATED:
1298 			DPRINTF("%s role -> DESIGNATED\n",
1299 			    bp->bp_ifp->if_xname);
1300 			bstp_timer_start(&bp->bp_hello_timer,
1301 			    bp->bp_desg_htime);
1302 			bp->bp_agree = 0;
1303 			break;
1304 	}
1305 
1306 	/* let the TC state know that the role changed */
1307 	bstp_update_tc(bp);
1308 }
1309 
1310 static void
1311 bstp_set_port_proto(struct bstp_port *bp, int proto)
1312 {
1313 	struct bstp_state *bs = bp->bp_bs;
1314 
1315 	/* supported protocol versions */
1316 	switch (proto) {
1317 		case BSTP_PROTO_STP:
1318 			/* we can downgrade protocols only */
1319 			bstp_timer_stop(&bp->bp_migrate_delay_timer);
1320 			/* clear unsupported features */
1321 			bp->bp_operedge = 0;
1322 			/* STP compat mode only uses 16 bits of the 32 */
1323 			if (bp->bp_path_cost > 65535)
1324 				bp->bp_path_cost = 65535;
1325 			break;
1326 
1327 		case BSTP_PROTO_RSTP:
1328 			bstp_timer_start(&bp->bp_migrate_delay_timer,
1329 			    bs->bs_migration_delay);
1330 			break;
1331 
1332 		default:
1333 			DPRINTF("Unsupported STP version %d\n", proto);
1334 			return;
1335 	}
1336 
1337 	bp->bp_protover = proto;
1338 	bp->bp_flags &= ~BSTP_PORT_CANMIGRATE;
1339 }
1340 
1341 static void
1342 bstp_set_port_tc(struct bstp_port *bp, int state)
1343 {
1344 	struct bstp_state *bs = bp->bp_bs;
1345 
1346 	bp->bp_tcstate = state;
1347 
1348 	/* initialise the new state */
1349 	switch (bp->bp_tcstate) {
1350 		case BSTP_TCSTATE_ACTIVE:
1351 			DPRINTF("%s -> TC_ACTIVE\n", bp->bp_ifp->if_xname);
1352 			/* nothing to do */
1353 			break;
1354 
1355 		case BSTP_TCSTATE_INACTIVE:
1356 			bstp_timer_stop(&bp->bp_tc_timer);
1357 			/* flush routes on the parent bridge */
1358 			bp->bp_fdbflush = 1;
1359 			taskqueue_enqueue(taskqueue_swi, &bp->bp_rtagetask);
1360 			bp->bp_tc_ack = 0;
1361 			DPRINTF("%s -> TC_INACTIVE\n", bp->bp_ifp->if_xname);
1362 			break;
1363 
1364 		case BSTP_TCSTATE_LEARNING:
1365 			bp->bp_rcvdtc = 0;
1366 			bp->bp_rcvdtcn = 0;
1367 			bp->bp_rcvdtca = 0;
1368 			bp->bp_tc_prop = 0;
1369 			DPRINTF("%s -> TC_LEARNING\n", bp->bp_ifp->if_xname);
1370 			break;
1371 
1372 		case BSTP_TCSTATE_DETECTED:
1373 			bstp_set_timer_tc(bp);
1374 			bstp_set_other_tcprop(bp);
1375 			/* send out notification */
1376 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1377 			bstp_transmit(bs, bp);
1378 			getmicrotime(&bs->bs_last_tc_time);
1379 			DPRINTF("%s -> TC_DETECTED\n", bp->bp_ifp->if_xname);
1380 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1381 			break;
1382 
1383 		case BSTP_TCSTATE_TCN:
1384 			bstp_set_timer_tc(bp);
1385 			DPRINTF("%s -> TC_TCN\n", bp->bp_ifp->if_xname);
1386 			/* fall through */
1387 		case BSTP_TCSTATE_TC:
1388 			bp->bp_rcvdtc = 0;
1389 			bp->bp_rcvdtcn = 0;
1390 			if (bp->bp_role == BSTP_ROLE_DESIGNATED)
1391 				bp->bp_tc_ack = 1;
1392 
1393 			bstp_set_other_tcprop(bp);
1394 			DPRINTF("%s -> TC_TC\n", bp->bp_ifp->if_xname);
1395 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1396 			break;
1397 
1398 		case BSTP_TCSTATE_PROPAG:
1399 			/* flush routes on the parent bridge */
1400 			bp->bp_fdbflush = 1;
1401 			taskqueue_enqueue(taskqueue_swi, &bp->bp_rtagetask);
1402 			bp->bp_tc_prop = 0;
1403 			bstp_set_timer_tc(bp);
1404 			DPRINTF("%s -> TC_PROPAG\n", bp->bp_ifp->if_xname);
1405 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1406 			break;
1407 
1408 		case BSTP_TCSTATE_ACK:
1409 			bstp_timer_stop(&bp->bp_tc_timer);
1410 			bp->bp_rcvdtca = 0;
1411 			DPRINTF("%s -> TC_ACK\n", bp->bp_ifp->if_xname);
1412 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1413 			break;
1414 	}
1415 }
1416 
1417 static void
1418 bstp_set_timer_tc(struct bstp_port *bp)
1419 {
1420 	struct bstp_state *bs = bp->bp_bs;
1421 
1422 	if (bp->bp_tc_timer.active)
1423 		return;
1424 
1425 	switch (bp->bp_protover) {
1426 		case BSTP_PROTO_RSTP:
1427 			bstp_timer_start(&bp->bp_tc_timer,
1428 			    bp->bp_desg_htime + BSTP_TICK_VAL);
1429 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1430 			break;
1431 
1432 		case BSTP_PROTO_STP:
1433 			bstp_timer_start(&bp->bp_tc_timer,
1434 			    bs->bs_root_max_age + bs->bs_root_fdelay);
1435 			break;
1436 	}
1437 }
1438 
1439 static void
1440 bstp_set_timer_msgage(struct bstp_port *bp)
1441 {
1442 	if (bp->bp_port_msg_age + BSTP_MESSAGE_AGE_INCR <=
1443 	    bp->bp_port_max_age) {
1444 		bstp_timer_start(&bp->bp_message_age_timer,
1445 		    bp->bp_port_htime * 3);
1446 	} else
1447 		/* expires immediately */
1448 		bstp_timer_start(&bp->bp_message_age_timer, 0);
1449 }
1450 
1451 static int
1452 bstp_rerooted(struct bstp_state *bs, struct bstp_port *bp)
1453 {
1454 	struct bstp_port *bp2;
1455 	int rr_set = 0;
1456 
1457 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1458 		if (bp2 == bp)
1459 			continue;
1460 		if (bp2->bp_recent_root_timer.active) {
1461 			rr_set = 1;
1462 			break;
1463 		}
1464 	}
1465 	return (!rr_set);
1466 }
1467 
1468 int
1469 bstp_set_htime(struct bstp_state *bs, int t)
1470 {
1471 	/* convert seconds to ticks */
1472 	t *=  BSTP_TICK_VAL;
1473 
1474 	/* value can only be changed in leagacy stp mode */
1475 	if (bs->bs_protover != BSTP_PROTO_STP)
1476 		return (EPERM);
1477 
1478 	if (t < BSTP_MIN_HELLO_TIME || t > BSTP_MAX_HELLO_TIME)
1479 		return (EINVAL);
1480 
1481 	BSTP_LOCK(bs);
1482 	bs->bs_bridge_htime = t;
1483 	bstp_reinit(bs);
1484 	BSTP_UNLOCK(bs);
1485 	return (0);
1486 }
1487 
1488 int
1489 bstp_set_fdelay(struct bstp_state *bs, int t)
1490 {
1491 	/* convert seconds to ticks */
1492 	t *= BSTP_TICK_VAL;
1493 
1494 	if (t < BSTP_MIN_FORWARD_DELAY || t > BSTP_MAX_FORWARD_DELAY)
1495 		return (EINVAL);
1496 
1497 	BSTP_LOCK(bs);
1498 	bs->bs_bridge_fdelay = t;
1499 	bstp_reinit(bs);
1500 	BSTP_UNLOCK(bs);
1501 	return (0);
1502 }
1503 
1504 int
1505 bstp_set_maxage(struct bstp_state *bs, int t)
1506 {
1507 	/* convert seconds to ticks */
1508 	t *= BSTP_TICK_VAL;
1509 
1510 	if (t < BSTP_MIN_MAX_AGE || t > BSTP_MAX_MAX_AGE)
1511 		return (EINVAL);
1512 
1513 	BSTP_LOCK(bs);
1514 	bs->bs_bridge_max_age = t;
1515 	bstp_reinit(bs);
1516 	BSTP_UNLOCK(bs);
1517 	return (0);
1518 }
1519 
1520 int
1521 bstp_set_holdcount(struct bstp_state *bs, int count)
1522 {
1523 	struct bstp_port *bp;
1524 
1525 	if (count < BSTP_MIN_HOLD_COUNT ||
1526 	    count > BSTP_MAX_HOLD_COUNT)
1527 		return (EINVAL);
1528 
1529 	BSTP_LOCK(bs);
1530 	bs->bs_txholdcount = count;
1531 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1532 		bp->bp_txcount = 0;
1533 	BSTP_UNLOCK(bs);
1534 	return (0);
1535 }
1536 
1537 int
1538 bstp_set_protocol(struct bstp_state *bs, int proto)
1539 {
1540 	struct bstp_port *bp;
1541 
1542 	switch (proto) {
1543 		/* Supported protocol versions */
1544 		case BSTP_PROTO_STP:
1545 		case BSTP_PROTO_RSTP:
1546 			break;
1547 
1548 		default:
1549 			return (EINVAL);
1550 	}
1551 
1552 	BSTP_LOCK(bs);
1553 	bs->bs_protover = proto;
1554 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
1555 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1556 		/* reinit state */
1557 		bp->bp_infois = BSTP_INFO_DISABLED;
1558 		bp->bp_txcount = 0;
1559 		bstp_set_port_proto(bp, bs->bs_protover);
1560 		bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
1561 		bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1562 		bstp_timer_stop(&bp->bp_recent_backup_timer);
1563 	}
1564 	bstp_reinit(bs);
1565 	BSTP_UNLOCK(bs);
1566 	return (0);
1567 }
1568 
1569 int
1570 bstp_set_priority(struct bstp_state *bs, int pri)
1571 {
1572 	if (pri < 0 || pri > BSTP_MAX_PRIORITY)
1573 		return (EINVAL);
1574 
1575 	/* Limit to steps of 4096 */
1576 	pri -= pri % 4096;
1577 
1578 	BSTP_LOCK(bs);
1579 	bs->bs_bridge_priority = pri;
1580 	bstp_reinit(bs);
1581 	BSTP_UNLOCK(bs);
1582 	return (0);
1583 }
1584 
1585 int
1586 bstp_set_port_priority(struct bstp_port *bp, int pri)
1587 {
1588 	struct bstp_state *bs = bp->bp_bs;
1589 
1590 	if (pri < 0 || pri > BSTP_MAX_PORT_PRIORITY)
1591 		return (EINVAL);
1592 
1593 	/* Limit to steps of 16 */
1594 	pri -= pri % 16;
1595 
1596 	BSTP_LOCK(bs);
1597 	bp->bp_priority = pri;
1598 	bstp_reinit(bs);
1599 	BSTP_UNLOCK(bs);
1600 	return (0);
1601 }
1602 
1603 int
1604 bstp_set_path_cost(struct bstp_port *bp, uint32_t path_cost)
1605 {
1606 	struct bstp_state *bs = bp->bp_bs;
1607 
1608 	if (path_cost > BSTP_MAX_PATH_COST)
1609 		return (EINVAL);
1610 
1611 	/* STP compat mode only uses 16 bits of the 32 */
1612 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1613 		path_cost = 65535;
1614 
1615 	BSTP_LOCK(bs);
1616 
1617 	if (path_cost == 0) {	/* use auto */
1618 		bp->bp_flags &= ~BSTP_PORT_ADMCOST;
1619 		bp->bp_path_cost = bstp_calc_path_cost(bp);
1620 	} else {
1621 		bp->bp_path_cost = path_cost;
1622 		bp->bp_flags |= BSTP_PORT_ADMCOST;
1623 	}
1624 	bstp_reinit(bs);
1625 	BSTP_UNLOCK(bs);
1626 	return (0);
1627 }
1628 
1629 int
1630 bstp_set_edge(struct bstp_port *bp, int set)
1631 {
1632 	struct bstp_state *bs = bp->bp_bs;
1633 
1634 	BSTP_LOCK(bs);
1635 	if ((bp->bp_operedge = set) == 0)
1636 		bp->bp_flags &= ~BSTP_PORT_ADMEDGE;
1637 	else
1638 		bp->bp_flags |= BSTP_PORT_ADMEDGE;
1639 	BSTP_UNLOCK(bs);
1640 	return (0);
1641 }
1642 
1643 int
1644 bstp_set_autoedge(struct bstp_port *bp, int set)
1645 {
1646 	struct bstp_state *bs = bp->bp_bs;
1647 
1648 	BSTP_LOCK(bs);
1649 	if (set) {
1650 		bp->bp_flags |= BSTP_PORT_AUTOEDGE;
1651 		/* we may be able to transition straight to edge */
1652 		if (bp->bp_edge_delay_timer.active == 0)
1653 			bstp_edge_delay_expiry(bs, bp);
1654 	} else
1655 		bp->bp_flags &= ~BSTP_PORT_AUTOEDGE;
1656 	BSTP_UNLOCK(bs);
1657 	return (0);
1658 }
1659 
1660 int
1661 bstp_set_ptp(struct bstp_port *bp, int set)
1662 {
1663 	struct bstp_state *bs = bp->bp_bs;
1664 
1665 	BSTP_LOCK(bs);
1666 	bp->bp_ptp_link = set;
1667 	BSTP_UNLOCK(bs);
1668 	return (0);
1669 }
1670 
1671 int
1672 bstp_set_autoptp(struct bstp_port *bp, int set)
1673 {
1674 	struct bstp_state *bs = bp->bp_bs;
1675 
1676 	BSTP_LOCK(bs);
1677 	if (set) {
1678 		bp->bp_flags |= BSTP_PORT_AUTOPTP;
1679 		if (bp->bp_role != BSTP_ROLE_DISABLED)
1680 			taskqueue_enqueue(taskqueue_swi, &bp->bp_mediatask);
1681 	} else
1682 		bp->bp_flags &= ~BSTP_PORT_AUTOPTP;
1683 	BSTP_UNLOCK(bs);
1684 	return (0);
1685 }
1686 
1687 /*
1688  * Calculate the path cost according to the link speed.
1689  */
1690 static uint32_t
1691 bstp_calc_path_cost(struct bstp_port *bp)
1692 {
1693 	struct ifnet *ifp = bp->bp_ifp;
1694 	uint32_t path_cost;
1695 
1696 	/* If the priority has been manually set then retain the value */
1697 	if (bp->bp_flags & BSTP_PORT_ADMCOST)
1698 		return bp->bp_path_cost;
1699 
1700 	if (ifp->if_link_state == LINK_STATE_DOWN) {
1701 		/* Recalc when the link comes up again */
1702 		bp->bp_flags |= BSTP_PORT_PNDCOST;
1703 		return (BSTP_DEFAULT_PATH_COST);
1704 	}
1705 
1706 	if (ifp->if_baudrate < 1000)
1707 		return (BSTP_DEFAULT_PATH_COST);
1708 
1709  	/* formula from section 17.14, IEEE Std 802.1D-2004 */
1710 	path_cost = 20000000000ULL / (ifp->if_baudrate / 1000);
1711 
1712 	if (path_cost > BSTP_MAX_PATH_COST)
1713 		path_cost = BSTP_MAX_PATH_COST;
1714 
1715 	/* STP compat mode only uses 16 bits of the 32 */
1716 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1717 		path_cost = 65535;
1718 
1719 	return (path_cost);
1720 }
1721 
1722 /*
1723  * Notify the bridge that a port state has changed, we need to do this from a
1724  * taskqueue to avoid a LOR.
1725  */
1726 static void
1727 bstp_notify_state(void *arg, int pending)
1728 {
1729 	struct bstp_port *bp = (struct bstp_port *)arg;
1730 	struct bstp_state *bs = bp->bp_bs;
1731 
1732 	if (bp->bp_active == 1 && bs->bs_state_cb != NULL)
1733 		(*bs->bs_state_cb)(bp->bp_ifp, bp->bp_state);
1734 }
1735 
1736 /*
1737  * Flush the routes on the bridge port, we need to do this from a
1738  * taskqueue to avoid a LOR.
1739  */
1740 static void
1741 bstp_notify_rtage(void *arg, int pending)
1742 {
1743 	struct bstp_port *bp = (struct bstp_port *)arg;
1744 	struct bstp_state *bs = bp->bp_bs;
1745 	int age = 0;
1746 
1747 	BSTP_LOCK(bs);
1748 	switch (bp->bp_protover) {
1749 		case BSTP_PROTO_STP:
1750 			/* convert to seconds */
1751 			age = bp->bp_desg_fdelay / BSTP_TICK_VAL;
1752 			break;
1753 
1754 		case BSTP_PROTO_RSTP:
1755 			age = 0;
1756 			break;
1757 	}
1758 	BSTP_UNLOCK(bs);
1759 
1760 	if (bp->bp_active == 1 && bs->bs_rtage_cb != NULL)
1761 		(*bs->bs_rtage_cb)(bp->bp_ifp, age);
1762 
1763 	/* flush is complete */
1764 	BSTP_LOCK(bs);
1765 	bp->bp_fdbflush = 0;
1766 	BSTP_UNLOCK(bs);
1767 }
1768 
1769 void
1770 bstp_linkstate(struct bstp_port *bp)
1771 {
1772 	struct bstp_state *bs = bp->bp_bs;
1773 
1774 	if (!bp->bp_active)
1775 		return;
1776 
1777 	bstp_ifupdstatus(bp, 0);
1778 	BSTP_LOCK(bs);
1779 	bstp_update_state(bs, bp);
1780 	BSTP_UNLOCK(bs);
1781 }
1782 
1783 static void
1784 bstp_ifupdstatus(void *arg, int pending)
1785 {
1786 	struct bstp_port *bp = (struct bstp_port *)arg;
1787 	struct bstp_state *bs = bp->bp_bs;
1788 	struct ifnet *ifp = bp->bp_ifp;
1789 	struct ifmediareq ifmr;
1790 	int error, changed;
1791 
1792 	if (!bp->bp_active)
1793 		return;
1794 
1795 	bzero((char *)&ifmr, sizeof(ifmr));
1796 	error = (*ifp->if_ioctl)(ifp, SIOCGIFMEDIA, (caddr_t)&ifmr);
1797 
1798 	BSTP_LOCK(bs);
1799 	changed = 0;
1800 	if ((error == 0) && (ifp->if_flags & IFF_UP)) {
1801 		if (ifmr.ifm_status & IFM_ACTIVE) {
1802 			/* A full-duplex link is assumed to be point to point */
1803 			if (bp->bp_flags & BSTP_PORT_AUTOPTP) {
1804 				int fdx;
1805 
1806 				fdx = ifmr.ifm_active & IFM_FDX ? 1 : 0;
1807 				if (bp->bp_ptp_link ^ fdx) {
1808 					bp->bp_ptp_link = fdx;
1809 					changed = 1;
1810 				}
1811 			}
1812 
1813 			/* Calc the cost if the link was down previously */
1814 			if (bp->bp_flags & BSTP_PORT_PNDCOST) {
1815 				uint32_t cost;
1816 
1817 				cost = bstp_calc_path_cost(bp);
1818 				if (bp->bp_path_cost != cost) {
1819 					bp->bp_path_cost = cost;
1820 					changed = 1;
1821 				}
1822 				bp->bp_flags &= ~BSTP_PORT_PNDCOST;
1823 			}
1824 
1825 			if (bp->bp_role == BSTP_ROLE_DISABLED) {
1826 				bstp_enable_port(bs, bp);
1827 				changed = 1;
1828 			}
1829 		} else {
1830 			if (bp->bp_role != BSTP_ROLE_DISABLED) {
1831 				bstp_disable_port(bs, bp);
1832 				changed = 1;
1833 				if ((bp->bp_flags & BSTP_PORT_ADMEDGE) &&
1834 				    bp->bp_protover == BSTP_PROTO_RSTP)
1835 					bp->bp_operedge = 1;
1836 			}
1837 		}
1838 	} else if (bp->bp_infois != BSTP_INFO_DISABLED) {
1839 		bstp_disable_port(bs, bp);
1840 		changed = 1;
1841 	}
1842 	if (changed)
1843 		bstp_assign_roles(bs);
1844 	BSTP_UNLOCK(bs);
1845 }
1846 
1847 static void
1848 bstp_enable_port(struct bstp_state *bs, struct bstp_port *bp)
1849 {
1850 	bp->bp_infois = BSTP_INFO_AGED;
1851 }
1852 
1853 static void
1854 bstp_disable_port(struct bstp_state *bs, struct bstp_port *bp)
1855 {
1856 	bp->bp_infois = BSTP_INFO_DISABLED;
1857 }
1858 
1859 static void
1860 bstp_tick(void *arg)
1861 {
1862 	struct bstp_state *bs = arg;
1863 	struct bstp_port *bp;
1864 
1865 	BSTP_LOCK_ASSERT(bs);
1866 
1867 	if (bs->bs_running == 0)
1868 		return;
1869 
1870 	CURVNET_SET(bs->bs_vnet);
1871 
1872 	/* poll link events on interfaces that do not support linkstate */
1873 	if (bstp_timer_dectest(&bs->bs_link_timer)) {
1874 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1875 			if (!(bp->bp_ifp->if_capabilities & IFCAP_LINKSTATE))
1876 				taskqueue_enqueue(taskqueue_swi, &bp->bp_mediatask);
1877 		}
1878 		bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
1879 	}
1880 
1881 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1882 		/* no events need to happen for these */
1883 		bstp_timer_dectest(&bp->bp_tc_timer);
1884 		bstp_timer_dectest(&bp->bp_recent_root_timer);
1885 		bstp_timer_dectest(&bp->bp_forward_delay_timer);
1886 		bstp_timer_dectest(&bp->bp_recent_backup_timer);
1887 
1888 		if (bstp_timer_dectest(&bp->bp_hello_timer))
1889 			bstp_hello_timer_expiry(bs, bp);
1890 
1891 		if (bstp_timer_dectest(&bp->bp_message_age_timer))
1892 			bstp_message_age_expiry(bs, bp);
1893 
1894 		if (bstp_timer_dectest(&bp->bp_migrate_delay_timer))
1895 			bstp_migrate_delay_expiry(bs, bp);
1896 
1897 		if (bstp_timer_dectest(&bp->bp_edge_delay_timer))
1898 			bstp_edge_delay_expiry(bs, bp);
1899 
1900 		/* update the various state machines for the port */
1901 		bstp_update_state(bs, bp);
1902 
1903 		if (bp->bp_txcount > 0)
1904 			bp->bp_txcount--;
1905 	}
1906 
1907 	CURVNET_RESTORE();
1908 
1909 	callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
1910 }
1911 
1912 static void
1913 bstp_timer_start(struct bstp_timer *t, uint16_t v)
1914 {
1915 	t->value = v;
1916 	t->active = 1;
1917 	t->latched = 0;
1918 }
1919 
1920 static void
1921 bstp_timer_stop(struct bstp_timer *t)
1922 {
1923 	t->value = 0;
1924 	t->active = 0;
1925 	t->latched = 0;
1926 }
1927 
1928 static void
1929 bstp_timer_latch(struct bstp_timer *t)
1930 {
1931 	t->latched = 1;
1932 	t->active = 1;
1933 }
1934 
1935 static int
1936 bstp_timer_dectest(struct bstp_timer *t)
1937 {
1938 	if (t->active == 0 || t->latched)
1939 		return (0);
1940 	t->value -= BSTP_TICK_VAL;
1941 	if (t->value <= 0) {
1942 		bstp_timer_stop(t);
1943 		return (1);
1944 	}
1945 	return (0);
1946 }
1947 
1948 static void
1949 bstp_hello_timer_expiry(struct bstp_state *bs, struct bstp_port *bp)
1950 {
1951 	if ((bp->bp_flags & BSTP_PORT_NEWINFO) ||
1952 	    bp->bp_role == BSTP_ROLE_DESIGNATED ||
1953 	    (bp->bp_role == BSTP_ROLE_ROOT &&
1954 	     bp->bp_tc_timer.active == 1)) {
1955 		bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
1956 		bp->bp_flags |= BSTP_PORT_NEWINFO;
1957 		bstp_transmit(bs, bp);
1958 	}
1959 }
1960 
1961 static void
1962 bstp_message_age_expiry(struct bstp_state *bs, struct bstp_port *bp)
1963 {
1964 	if (bp->bp_infois == BSTP_INFO_RECEIVED) {
1965 		bp->bp_infois = BSTP_INFO_AGED;
1966 		bstp_assign_roles(bs);
1967 		DPRINTF("aged info on %s\n", bp->bp_ifp->if_xname);
1968 	}
1969 }
1970 
1971 static void
1972 bstp_migrate_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1973 {
1974 	bp->bp_flags |= BSTP_PORT_CANMIGRATE;
1975 }
1976 
1977 static void
1978 bstp_edge_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1979 {
1980 	if ((bp->bp_flags & BSTP_PORT_AUTOEDGE) &&
1981 	    bp->bp_protover == BSTP_PROTO_RSTP && bp->bp_proposing &&
1982 	    bp->bp_role == BSTP_ROLE_DESIGNATED) {
1983 		bp->bp_operedge = 1;
1984 		DPRINTF("%s -> edge port\n", bp->bp_ifp->if_xname);
1985 	}
1986 }
1987 
1988 static int
1989 bstp_addr_cmp(const uint8_t *a, const uint8_t *b)
1990 {
1991 	int i, d;
1992 
1993 	for (i = 0, d = 0; i < ETHER_ADDR_LEN && d == 0; i++) {
1994 		d = ((int)a[i]) - ((int)b[i]);
1995 	}
1996 
1997 	return (d);
1998 }
1999 
2000 /*
2001  * compare the bridge address component of the bridgeid
2002  */
2003 static int
2004 bstp_same_bridgeid(uint64_t id1, uint64_t id2)
2005 {
2006 	u_char addr1[ETHER_ADDR_LEN];
2007 	u_char addr2[ETHER_ADDR_LEN];
2008 
2009 	PV2ADDR(id1, addr1);
2010 	PV2ADDR(id2, addr2);
2011 
2012 	if (bstp_addr_cmp(addr1, addr2) == 0)
2013 		return (1);
2014 
2015 	return (0);
2016 }
2017 
2018 void
2019 bstp_reinit(struct bstp_state *bs)
2020 {
2021 	struct bstp_port *bp;
2022 	struct ifnet *ifp, *mif;
2023 	u_char *e_addr;
2024 	void *bridgeptr;
2025 	static const u_char llzero[ETHER_ADDR_LEN];	/* 00:00:00:00:00:00 */
2026 
2027 	BSTP_LOCK_ASSERT(bs);
2028 
2029 	if (LIST_EMPTY(&bs->bs_bplist))
2030 		goto disablestp;
2031 
2032 	mif = NULL;
2033 	bridgeptr = LIST_FIRST(&bs->bs_bplist)->bp_ifp->if_bridge;
2034 	KASSERT(bridgeptr != NULL, ("Invalid bridge pointer"));
2035 	/*
2036 	 * Search through the Ethernet adapters and find the one with the
2037 	 * lowest value. Make sure the adapter which we take the MAC address
2038 	 * from is part of this bridge, so we can have more than one independent
2039 	 * bridges in the same STP domain.
2040 	 */
2041 	IFNET_RLOCK_NOSLEEP();
2042 	TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
2043 		if (ifp->if_type != IFT_ETHER)
2044 			continue;	/* Not Ethernet */
2045 
2046 		if (ifp->if_bridge != bridgeptr)
2047 			continue;	/* Not part of our bridge */
2048 
2049 		if (bstp_addr_cmp(IF_LLADDR(ifp), llzero) == 0)
2050 			continue;	/* No mac address set */
2051 
2052 		if (mif == NULL) {
2053 			mif = ifp;
2054 			continue;
2055 		}
2056 		if (bstp_addr_cmp(IF_LLADDR(ifp), IF_LLADDR(mif)) < 0) {
2057 			mif = ifp;
2058 			continue;
2059 		}
2060 	}
2061 	IFNET_RUNLOCK_NOSLEEP();
2062 	if (mif == NULL)
2063 		goto disablestp;
2064 
2065 	e_addr = IF_LLADDR(mif);
2066 	bs->bs_bridge_pv.pv_dbridge_id =
2067 	    (((uint64_t)bs->bs_bridge_priority) << 48) |
2068 	    (((uint64_t)e_addr[0]) << 40) |
2069 	    (((uint64_t)e_addr[1]) << 32) |
2070 	    (((uint64_t)e_addr[2]) << 24) |
2071 	    (((uint64_t)e_addr[3]) << 16) |
2072 	    (((uint64_t)e_addr[4]) << 8) |
2073 	    (((uint64_t)e_addr[5]));
2074 
2075 	bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
2076 	bs->bs_bridge_pv.pv_cost = 0;
2077 	bs->bs_bridge_pv.pv_dport_id = 0;
2078 	bs->bs_bridge_pv.pv_port_id = 0;
2079 
2080 	if (bs->bs_running && callout_pending(&bs->bs_bstpcallout) == 0)
2081 		callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
2082 
2083 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2084 		bp->bp_port_id = (bp->bp_priority << 8) |
2085 		    (bp->bp_ifp->if_index  & 0xfff);
2086 		taskqueue_enqueue(taskqueue_swi, &bp->bp_mediatask);
2087 	}
2088 
2089 	bstp_assign_roles(bs);
2090 	bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
2091 	return;
2092 
2093 disablestp:
2094 	/* Set the bridge and root id (lower bits) to zero */
2095 	bs->bs_bridge_pv.pv_dbridge_id =
2096 	    ((uint64_t)bs->bs_bridge_priority) << 48;
2097 	bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
2098 	bs->bs_root_pv = bs->bs_bridge_pv;
2099 	/* Disable any remaining ports, they will have no MAC address */
2100 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2101 		bp->bp_infois = BSTP_INFO_DISABLED;
2102 		bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2103 	}
2104 	callout_stop(&bs->bs_bstpcallout);
2105 }
2106 
2107 static int
2108 bstp_modevent(module_t mod, int type, void *data)
2109 {
2110 	switch (type) {
2111 	case MOD_LOAD:
2112 		mtx_init(&bstp_list_mtx, "bridgestp list", NULL, MTX_DEF);
2113 		LIST_INIT(&bstp_list);
2114 		break;
2115 	case MOD_UNLOAD:
2116 		mtx_destroy(&bstp_list_mtx);
2117 		break;
2118 	default:
2119 		return (EOPNOTSUPP);
2120 	}
2121 	return (0);
2122 }
2123 
2124 static moduledata_t bstp_mod = {
2125 	"bridgestp",
2126 	bstp_modevent,
2127 	0
2128 };
2129 
2130 DECLARE_MODULE(bridgestp, bstp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
2131 MODULE_VERSION(bridgestp, 1);
2132 
2133 void
2134 bstp_attach(struct bstp_state *bs, struct bstp_cb_ops *cb)
2135 {
2136 	BSTP_LOCK_INIT(bs);
2137 	callout_init_mtx(&bs->bs_bstpcallout, &bs->bs_mtx, 0);
2138 	LIST_INIT(&bs->bs_bplist);
2139 
2140 	bs->bs_bridge_max_age = BSTP_DEFAULT_MAX_AGE;
2141 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
2142 	bs->bs_bridge_fdelay = BSTP_DEFAULT_FORWARD_DELAY;
2143 	bs->bs_bridge_priority = BSTP_DEFAULT_BRIDGE_PRIORITY;
2144 	bs->bs_hold_time = BSTP_DEFAULT_HOLD_TIME;
2145 	bs->bs_migration_delay = BSTP_DEFAULT_MIGRATE_DELAY;
2146 	bs->bs_txholdcount = BSTP_DEFAULT_HOLD_COUNT;
2147 	bs->bs_protover = BSTP_PROTO_RSTP;
2148 	bs->bs_state_cb = cb->bcb_state;
2149 	bs->bs_rtage_cb = cb->bcb_rtage;
2150 	bs->bs_vnet = curvnet;
2151 
2152 	getmicrotime(&bs->bs_last_tc_time);
2153 
2154 	mtx_lock(&bstp_list_mtx);
2155 	LIST_INSERT_HEAD(&bstp_list, bs, bs_list);
2156 	mtx_unlock(&bstp_list_mtx);
2157 }
2158 
2159 void
2160 bstp_detach(struct bstp_state *bs)
2161 {
2162 	KASSERT(LIST_EMPTY(&bs->bs_bplist), ("bstp still active"));
2163 
2164 	mtx_lock(&bstp_list_mtx);
2165 	LIST_REMOVE(bs, bs_list);
2166 	mtx_unlock(&bstp_list_mtx);
2167 	callout_drain(&bs->bs_bstpcallout);
2168 	BSTP_LOCK_DESTROY(bs);
2169 }
2170 
2171 void
2172 bstp_init(struct bstp_state *bs)
2173 {
2174 	BSTP_LOCK(bs);
2175 	callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
2176 	bs->bs_running = 1;
2177 	bstp_reinit(bs);
2178 	BSTP_UNLOCK(bs);
2179 }
2180 
2181 void
2182 bstp_stop(struct bstp_state *bs)
2183 {
2184 	struct bstp_port *bp;
2185 
2186 	BSTP_LOCK(bs);
2187 
2188 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
2189 		bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
2190 
2191 	bs->bs_running = 0;
2192 	callout_stop(&bs->bs_bstpcallout);
2193 	BSTP_UNLOCK(bs);
2194 }
2195 
2196 int
2197 bstp_create(struct bstp_state *bs, struct bstp_port *bp, struct ifnet *ifp)
2198 {
2199 	bzero(bp, sizeof(struct bstp_port));
2200 
2201 	BSTP_LOCK(bs);
2202 	bp->bp_ifp = ifp;
2203 	bp->bp_bs = bs;
2204 	bp->bp_priority = BSTP_DEFAULT_PORT_PRIORITY;
2205 	TASK_INIT(&bp->bp_statetask, 0, bstp_notify_state, bp);
2206 	TASK_INIT(&bp->bp_rtagetask, 0, bstp_notify_rtage, bp);
2207 	TASK_INIT(&bp->bp_mediatask, 0, bstp_ifupdstatus, bp);
2208 
2209 	/* Init state */
2210 	bp->bp_infois = BSTP_INFO_DISABLED;
2211 	bp->bp_flags = BSTP_PORT_AUTOEDGE|BSTP_PORT_AUTOPTP;
2212 	bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
2213 	bstp_set_port_proto(bp, bs->bs_protover);
2214 	bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2215 	bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
2216 	bp->bp_path_cost = bstp_calc_path_cost(bp);
2217 	BSTP_UNLOCK(bs);
2218 	return (0);
2219 }
2220 
2221 int
2222 bstp_enable(struct bstp_port *bp)
2223 {
2224 	struct bstp_state *bs = bp->bp_bs;
2225 	struct ifnet *ifp = bp->bp_ifp;
2226 
2227 	KASSERT(bp->bp_active == 0, ("already a bstp member"));
2228 
2229 	switch (ifp->if_type) {
2230 		case IFT_ETHER:	/* These can do spanning tree. */
2231 			break;
2232 		default:
2233 			/* Nothing else can. */
2234 			return (EINVAL);
2235 	}
2236 
2237 	BSTP_LOCK(bs);
2238 	LIST_INSERT_HEAD(&bs->bs_bplist, bp, bp_next);
2239 	bp->bp_active = 1;
2240 	bp->bp_flags |= BSTP_PORT_NEWINFO;
2241 	bstp_reinit(bs);
2242 	bstp_update_roles(bs, bp);
2243 	BSTP_UNLOCK(bs);
2244 	return (0);
2245 }
2246 
2247 void
2248 bstp_disable(struct bstp_port *bp)
2249 {
2250 	struct bstp_state *bs = bp->bp_bs;
2251 
2252 	KASSERT(bp->bp_active == 1, ("not a bstp member"));
2253 
2254 	BSTP_LOCK(bs);
2255 	bstp_disable_port(bs, bp);
2256 	LIST_REMOVE(bp, bp_next);
2257 	bp->bp_active = 0;
2258 	bstp_reinit(bs);
2259 	BSTP_UNLOCK(bs);
2260 }
2261 
2262 /*
2263  * The bstp_port structure is about to be freed by the parent bridge.
2264  */
2265 void
2266 bstp_destroy(struct bstp_port *bp)
2267 {
2268 	KASSERT(bp->bp_active == 0, ("port is still attached"));
2269 	taskqueue_drain(taskqueue_swi, &bp->bp_statetask);
2270 	taskqueue_drain(taskqueue_swi, &bp->bp_rtagetask);
2271 	taskqueue_drain(taskqueue_swi, &bp->bp_mediatask);
2272 }
2273