xref: /freebsd/sys/net/bridgestp.c (revision 160e76972a85398e1d8d19143c145cb8a6f6942e)
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 
59 #include <netinet/in.h>
60 #include <netinet/in_systm.h>
61 #include <netinet/in_var.h>
62 #include <netinet/if_ether.h>
63 #include <net/bridgestp.h>
64 
65 #ifdef	BRIDGESTP_DEBUG
66 #define	DPRINTF(fmt, arg...)	printf("bstp: " fmt, ##arg)
67 #else
68 #define	DPRINTF(fmt, arg...)
69 #endif
70 
71 #define	PV2ADDR(pv, eaddr)	do {		\
72 	eaddr[0] = pv >> 40;			\
73 	eaddr[1] = pv >> 32;			\
74 	eaddr[2] = pv >> 24;			\
75 	eaddr[3] = pv >> 16;			\
76 	eaddr[4] = pv >> 8;			\
77 	eaddr[5] = pv >> 0;			\
78 } while (0)
79 
80 #define	INFO_BETTER	1
81 #define	INFO_SAME	0
82 #define	INFO_WORSE	-1
83 
84 const uint8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
85 
86 LIST_HEAD(, bstp_state) bstp_list;
87 static struct mtx	bstp_list_mtx;
88 
89 static void	bstp_transmit(struct bstp_state *, struct bstp_port *);
90 static void	bstp_transmit_bpdu(struct bstp_state *, struct bstp_port *);
91 static void	bstp_transmit_tcn(struct bstp_state *, struct bstp_port *);
92 static void	bstp_decode_bpdu(struct bstp_port *, struct bstp_cbpdu *,
93 		    struct bstp_config_unit *);
94 static void	bstp_send_bpdu(struct bstp_state *, struct bstp_port *,
95 		    struct bstp_cbpdu *);
96 static void	bstp_enqueue(struct ifnet *, struct mbuf *);
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(struct bstp_state *, struct bstp_port *);
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_expired(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 	MGETHDR(m, M_DONTWAIT, 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 	bstp_enqueue(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 	MGETHDR(m, M_DONTWAIT, 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 	bstp_enqueue(ifp, m);
390 }
391 
392 static void
393 bstp_enqueue(struct ifnet *dst_ifp, struct mbuf *m)
394 {
395 	int err = 0;
396 
397 	IFQ_ENQUEUE(&dst_ifp->if_snd, m, err);
398 
399 	if ((dst_ifp->if_drv_flags & IFF_DRV_OACTIVE) == 0)
400 		(*dst_ifp->if_start)(dst_ifp);
401 }
402 
403 static int
404 bstp_pdu_flags(struct bstp_port *bp)
405 {
406 	int flags = 0;
407 
408 	if (bp->bp_proposing && bp->bp_state != BSTP_IFSTATE_FORWARDING)
409 		flags |= BSTP_PDU_F_P;
410 
411 	if (bp->bp_agree)
412 		flags |= BSTP_PDU_F_A;
413 
414 	if (bp->bp_tc_timer.active)
415 		flags |= BSTP_PDU_F_TC;
416 
417 	if (bp->bp_tc_ack)
418 		flags |= BSTP_PDU_F_TCA;
419 
420 	switch (bp->bp_state) {
421 		case BSTP_IFSTATE_LEARNING:
422 			flags |= BSTP_PDU_F_L;
423 			break;
424 
425 		case BSTP_IFSTATE_FORWARDING:
426 			flags |= (BSTP_PDU_F_L | BSTP_PDU_F_F);
427 			break;
428 	}
429 
430 	switch (bp->bp_role) {
431 		case BSTP_ROLE_ROOT:
432 			flags |=
433 				(BSTP_PDU_F_ROOT << BSTP_PDU_PRSHIFT);
434 			break;
435 
436 		case BSTP_ROLE_ALTERNATE:
437 		case BSTP_ROLE_BACKUP:	/* fall through */
438 			flags |=
439 				(BSTP_PDU_F_ALT << BSTP_PDU_PRSHIFT);
440 			break;
441 
442 		case BSTP_ROLE_DESIGNATED:
443 			flags |=
444 				(BSTP_PDU_F_DESG << BSTP_PDU_PRSHIFT);
445 			break;
446 	}
447 
448 	/* Strip off unused flags in either mode */
449 	switch (bp->bp_protover) {
450 		case BSTP_PROTO_STP:
451 			flags &= BSTP_PDU_STPMASK;
452 			break;
453 		case BSTP_PROTO_RSTP:
454 			flags &= BSTP_PDU_RSTPMASK;
455 			break;
456 	}
457 	return (flags);
458 }
459 
460 struct mbuf *
461 bstp_input(struct bstp_port *bp, struct ifnet *ifp, struct mbuf *m)
462 {
463 	struct bstp_state *bs = bp->bp_bs;
464 	struct ether_header *eh;
465 	struct bstp_tbpdu tpdu;
466 	uint16_t len;
467 
468 	if (bp->bp_active == 0) {
469 		m_freem(m);
470 		return (NULL);
471 	}
472 
473 	BSTP_LOCK(bs);
474 
475 	eh = mtod(m, struct ether_header *);
476 
477 	len = ntohs(eh->ether_type);
478 	if (len < sizeof(tpdu))
479 		goto out;
480 
481 	m_adj(m, ETHER_HDR_LEN);
482 
483 	if (m->m_pkthdr.len > len)
484 		m_adj(m, len - m->m_pkthdr.len);
485 	if (m->m_len < sizeof(tpdu) &&
486 	    (m = m_pullup(m, sizeof(tpdu))) == NULL)
487 		goto out;
488 
489 	memcpy(&tpdu, mtod(m, caddr_t), sizeof(tpdu));
490 
491 	/* basic packet checks */
492 	if (tpdu.tbu_dsap != LLC_8021D_LSAP ||
493 	    tpdu.tbu_ssap != LLC_8021D_LSAP ||
494 	    tpdu.tbu_ctl != LLC_UI)
495 		goto out;
496 	if (tpdu.tbu_protoid != BSTP_PROTO_ID)
497 		goto out;
498 
499 	/*
500 	 * We can treat later versions of the PDU as the same as the maximum
501 	 * version we implement. All additional parameters/flags are ignored.
502 	 */
503 	if (tpdu.tbu_protover > BSTP_PROTO_MAX)
504 		tpdu.tbu_protover = BSTP_PROTO_MAX;
505 
506 	if (tpdu.tbu_protover != bp->bp_protover) {
507 		/*
508 		 * Wait for the migration delay timer to expire before changing
509 		 * protocol version to avoid flip-flops.
510 		 */
511 		if (bp->bp_flags & BSTP_PORT_CANMIGRATE)
512 			bstp_set_port_proto(bp, tpdu.tbu_protover);
513 		else
514 			goto out;
515 	}
516 
517 	/* Clear operedge upon receiving a PDU on the port */
518 	bp->bp_operedge = 0;
519 	bstp_timer_start(&bp->bp_edge_delay_timer,
520 	    BSTP_DEFAULT_MIGRATE_DELAY);
521 
522 	switch (tpdu.tbu_protover) {
523 		case BSTP_PROTO_STP:
524 			bstp_received_stp(bs, bp, &m, &tpdu);
525 			break;
526 
527 		case BSTP_PROTO_RSTP:
528 			bstp_received_rstp(bs, bp, &m, &tpdu);
529 			break;
530 	}
531 out:
532 	BSTP_UNLOCK(bs);
533 	if (m)
534 		m_freem(m);
535 	return (NULL);
536 }
537 
538 static void
539 bstp_received_stp(struct bstp_state *bs, struct bstp_port *bp,
540     struct mbuf **mp, struct bstp_tbpdu *tpdu)
541 {
542 	struct bstp_cbpdu cpdu;
543 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
544 	struct bstp_tcn_unit tu;
545 
546 	switch (tpdu->tbu_bpdutype) {
547 	case BSTP_MSGTYPE_TCN:
548 		tu.tu_message_type = tpdu->tbu_bpdutype;
549 		bstp_received_tcn(bs, bp, &tu);
550 		break;
551 	case BSTP_MSGTYPE_CFG:
552 		if ((*mp)->m_len < BSTP_BPDU_STP_LEN &&
553 		    (*mp = m_pullup(*mp, BSTP_BPDU_STP_LEN)) == NULL)
554 			return;
555 		memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_STP_LEN);
556 
557 		bstp_decode_bpdu(bp, &cpdu, cu);
558 		bstp_received_bpdu(bs, bp, cu);
559 		break;
560 	}
561 }
562 
563 static void
564 bstp_received_rstp(struct bstp_state *bs, struct bstp_port *bp,
565     struct mbuf **mp, struct bstp_tbpdu *tpdu)
566 {
567 	struct bstp_cbpdu cpdu;
568 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
569 
570 	if (tpdu->tbu_bpdutype != BSTP_MSGTYPE_RSTP)
571 		return;
572 
573 	if ((*mp)->m_len < BSTP_BPDU_RSTP_LEN &&
574 	    (*mp = m_pullup(*mp, BSTP_BPDU_RSTP_LEN)) == NULL)
575 		return;
576 	memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_RSTP_LEN);
577 
578 	bstp_decode_bpdu(bp, &cpdu, cu);
579 	bstp_received_bpdu(bs, bp, cu);
580 }
581 
582 static void
583 bstp_received_tcn(struct bstp_state *bs, struct bstp_port *bp,
584     struct bstp_tcn_unit *tcn)
585 {
586 	bp->bp_rcvdtcn = 1;
587 	bstp_update_tc(bp);
588 }
589 
590 static void
591 bstp_received_bpdu(struct bstp_state *bs, struct bstp_port *bp,
592     struct bstp_config_unit *cu)
593 {
594 	int type;
595 
596 	BSTP_LOCK_ASSERT(bs);
597 
598 	/* We need to have transitioned to INFO_MINE before proceeding */
599 	switch (bp->bp_infois) {
600 		case BSTP_INFO_DISABLED:
601 		case BSTP_INFO_AGED:
602 			return;
603 	}
604 
605 	type = bstp_pdu_rcvtype(bp, cu);
606 
607 	switch (type) {
608 		case BSTP_PDU_SUPERIOR:
609 			bs->bs_allsynced = 0;
610 			bp->bp_agreed = 0;
611 			bp->bp_proposing = 0;
612 
613 			if (cu->cu_proposal && cu->cu_forwarding == 0)
614 				bp->bp_proposed = 1;
615 			if (cu->cu_topology_change)
616 				bp->bp_rcvdtc = 1;
617 			if (cu->cu_topology_change_ack)
618 				bp->bp_rcvdtca = 1;
619 
620 			if (bp->bp_agree &&
621 			    !bstp_pdu_bettersame(bp, BSTP_INFO_RECEIVED))
622 				bp->bp_agree = 0;
623 
624 			/* copy the received priority and timers to the port */
625 			bp->bp_port_pv = cu->cu_pv;
626 			bp->bp_port_msg_age = cu->cu_message_age;
627 			bp->bp_port_max_age = cu->cu_max_age;
628 			bp->bp_port_fdelay = cu->cu_forward_delay;
629 			bp->bp_port_htime =
630 				(cu->cu_hello_time > BSTP_MIN_HELLO_TIME ?
631 				 cu->cu_hello_time : BSTP_MIN_HELLO_TIME);
632 
633 			/* set expiry for the new info */
634 			bstp_set_timer_msgage(bp);
635 
636 			bp->bp_infois = BSTP_INFO_RECEIVED;
637 			bstp_assign_roles(bs);
638 			break;
639 
640 		case BSTP_PDU_REPEATED:
641 			if (cu->cu_proposal && cu->cu_forwarding == 0)
642 				bp->bp_proposed = 1;
643 			if (cu->cu_topology_change)
644 				bp->bp_rcvdtc = 1;
645 			if (cu->cu_topology_change_ack)
646 				bp->bp_rcvdtca = 1;
647 
648 			/* rearm the age timer */
649 			bstp_set_timer_msgage(bp);
650 			break;
651 
652 		case BSTP_PDU_INFERIOR:
653 			if (cu->cu_learning) {
654 				bp->bp_agreed = 1;
655 				bp->bp_proposing = 0;
656 			}
657 			break;
658 
659 		case BSTP_PDU_INFERIORALT:
660 			/*
661 			 * only point to point links are allowed fast
662 			 * transitions to forwarding.
663 			 */
664 			if (cu->cu_agree && bp->bp_ptp_link) {
665 				bp->bp_agreed = 1;
666 				bp->bp_proposing = 0;
667 			} else
668 				bp->bp_agreed = 0;
669 
670 			if (cu->cu_topology_change)
671 				bp->bp_rcvdtc = 1;
672 			if (cu->cu_topology_change_ack)
673 				bp->bp_rcvdtca = 1;
674 			break;
675 
676 		case BSTP_PDU_OTHER:
677 			return;	/* do nothing */
678 	}
679 	/* update the state machines with the new data */
680 	bstp_update_state(bs, bp);
681 }
682 
683 static int
684 bstp_pdu_rcvtype(struct bstp_port *bp, struct bstp_config_unit *cu)
685 {
686 	int type;
687 
688 	/* default return type */
689 	type = BSTP_PDU_OTHER;
690 
691 	switch (cu->cu_role) {
692 	case BSTP_ROLE_DESIGNATED:
693 		if (bstp_info_superior(&bp->bp_port_pv, &cu->cu_pv))
694 			/* bpdu priority is superior */
695 			type = BSTP_PDU_SUPERIOR;
696 		else if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) ==
697 		    INFO_SAME) {
698 			if (bp->bp_port_msg_age != cu->cu_message_age ||
699 			    bp->bp_port_max_age != cu->cu_max_age ||
700 			    bp->bp_port_fdelay != cu->cu_forward_delay ||
701 			    bp->bp_port_htime != cu->cu_hello_time)
702 				/* bpdu priority is equal and timers differ */
703 				type = BSTP_PDU_SUPERIOR;
704 			else
705 				/* bpdu is equal */
706 				type = BSTP_PDU_REPEATED;
707 		} else
708 			/* bpdu priority is worse */
709 			type = BSTP_PDU_INFERIOR;
710 
711 		break;
712 
713 	case BSTP_ROLE_ROOT:
714 	case BSTP_ROLE_ALTERNATE:
715 	case BSTP_ROLE_BACKUP:
716 		if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) <= INFO_SAME)
717 			/*
718 			 * not a designated port and priority is the same or
719 			 * worse
720 			 */
721 			type = BSTP_PDU_INFERIORALT;
722 		break;
723 	}
724 
725 	return (type);
726 }
727 
728 static int
729 bstp_pdu_bettersame(struct bstp_port *bp, int newinfo)
730 {
731 	if (newinfo == BSTP_INFO_RECEIVED &&
732 	    bp->bp_infois == BSTP_INFO_RECEIVED &&
733 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_msg_cu.cu_pv) >= INFO_SAME)
734 		return (1);
735 
736 	if (newinfo == BSTP_INFO_MINE &&
737 	    bp->bp_infois == BSTP_INFO_MINE &&
738 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_desg_pv) >= INFO_SAME)
739 		return (1);
740 
741 	return (0);
742 }
743 
744 static int
745 bstp_info_cmp(struct bstp_pri_vector *pv,
746     struct bstp_pri_vector *cpv)
747 {
748 	if (cpv->pv_root_id < pv->pv_root_id)
749 		return (INFO_BETTER);
750 	if (cpv->pv_root_id > pv->pv_root_id)
751 		return (INFO_WORSE);
752 
753 	if (cpv->pv_cost < pv->pv_cost)
754 		return (INFO_BETTER);
755 	if (cpv->pv_cost > pv->pv_cost)
756 		return (INFO_WORSE);
757 
758 	if (cpv->pv_dbridge_id < pv->pv_dbridge_id)
759 		return (INFO_BETTER);
760 	if (cpv->pv_dbridge_id > pv->pv_dbridge_id)
761 		return (INFO_WORSE);
762 
763 	if (cpv->pv_dport_id < pv->pv_dport_id)
764 		return (INFO_BETTER);
765 	if (cpv->pv_dport_id > pv->pv_dport_id)
766 		return (INFO_WORSE);
767 
768 	return (INFO_SAME);
769 }
770 
771 /*
772  * This message priority vector is superior to the port priority vector and
773  * will replace it if, and only if, the message priority vector is better than
774  * the port priority vector, or the message has been transmitted from the same
775  * designated bridge and designated port as the port priority vector.
776  */
777 static int
778 bstp_info_superior(struct bstp_pri_vector *pv,
779     struct bstp_pri_vector *cpv)
780 {
781 	if (bstp_info_cmp(pv, cpv) == INFO_BETTER ||
782 	    (bstp_same_bridgeid(pv->pv_dbridge_id, cpv->pv_dbridge_id) &&
783 	    (cpv->pv_dport_id & 0xfff) == (pv->pv_dport_id & 0xfff)))
784 		return (1);
785 	return (0);
786 }
787 
788 static void
789 bstp_assign_roles(struct bstp_state *bs)
790 {
791 	struct bstp_port *bp, *rbp = NULL;
792 	struct bstp_pri_vector pv;
793 
794 	/* default to our priority vector */
795 	bs->bs_root_pv = bs->bs_bridge_pv;
796 	bs->bs_root_msg_age = 0;
797 	bs->bs_root_max_age = bs->bs_bridge_max_age;
798 	bs->bs_root_fdelay = bs->bs_bridge_fdelay;
799 	bs->bs_root_htime = bs->bs_bridge_htime;
800 	bs->bs_root_port = NULL;
801 
802 	/* check if any recieved info supersedes us */
803 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
804 		if (bp->bp_infois != BSTP_INFO_RECEIVED)
805 			continue;
806 
807 		pv = bp->bp_port_pv;
808 		pv.pv_cost += bp->bp_path_cost;
809 
810 		/*
811 		 * The root priority vector is the best of the set comprising
812 		 * the bridge priority vector plus all root path priority
813 		 * vectors whose bridge address is not equal to us.
814 		 */
815 		if (bstp_same_bridgeid(pv.pv_dbridge_id,
816 		    bs->bs_bridge_pv.pv_dbridge_id) == 0 &&
817 		    bstp_info_cmp(&bs->bs_root_pv, &pv) == INFO_BETTER) {
818 			/* the port vector replaces the root */
819 			bs->bs_root_pv = pv;
820 			bs->bs_root_msg_age = bp->bp_port_msg_age +
821 			    BSTP_MESSAGE_AGE_INCR;
822 			bs->bs_root_max_age = bp->bp_port_max_age;
823 			bs->bs_root_fdelay = bp->bp_port_fdelay;
824 			bs->bs_root_htime = bp->bp_port_htime;
825 			rbp = bp;
826 		}
827 	}
828 
829 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
830 		/* calculate the port designated vector */
831 		bp->bp_desg_pv.pv_root_id = bs->bs_root_pv.pv_root_id;
832 		bp->bp_desg_pv.pv_cost = bs->bs_root_pv.pv_cost;
833 		bp->bp_desg_pv.pv_dbridge_id = bs->bs_bridge_pv.pv_dbridge_id;
834 		bp->bp_desg_pv.pv_dport_id = bp->bp_port_id;
835 		bp->bp_desg_pv.pv_port_id = bp->bp_port_id;
836 
837 		/* calculate designated times */
838 		bp->bp_desg_msg_age = bs->bs_root_msg_age;
839 		bp->bp_desg_max_age = bs->bs_root_max_age;
840 		bp->bp_desg_fdelay = bs->bs_root_fdelay;
841 		bp->bp_desg_htime = bs->bs_bridge_htime;
842 
843 
844 		switch (bp->bp_infois) {
845 		case BSTP_INFO_DISABLED:
846 			bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
847 			break;
848 
849 		case BSTP_INFO_AGED:
850 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
851 			bstp_update_info(bp);
852 			break;
853 
854 		case BSTP_INFO_MINE:
855 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
856 			/* update the port info if stale */
857 			if (bstp_info_cmp(&bp->bp_port_pv,
858 			    &bp->bp_desg_pv) != INFO_SAME ||
859 			    (rbp != NULL &&
860 			    (bp->bp_port_msg_age != rbp->bp_port_msg_age ||
861 			    bp->bp_port_max_age != rbp->bp_port_max_age ||
862 			    bp->bp_port_fdelay != rbp->bp_port_fdelay ||
863 			    bp->bp_port_htime != rbp->bp_port_htime)))
864 				bstp_update_info(bp);
865 			break;
866 
867 		case BSTP_INFO_RECEIVED:
868 			if (bp == rbp) {
869 				/*
870 				 * root priority is derived from this
871 				 * port, make it the root port.
872 				 */
873 				bstp_set_port_role(bp, BSTP_ROLE_ROOT);
874 				bs->bs_root_port = bp;
875 			} else if (bstp_info_cmp(&bp->bp_port_pv,
876 				    &bp->bp_desg_pv) == INFO_BETTER) {
877 				/*
878 				 * the port priority is lower than the root
879 				 * port.
880 				 */
881 				bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
882 				bstp_update_info(bp);
883 			} else {
884 				if (bstp_same_bridgeid(
885 				    bp->bp_port_pv.pv_dbridge_id,
886 				    bs->bs_bridge_pv.pv_dbridge_id)) {
887 					/*
888 					 * the designated bridge refers to
889 					 * another port on this bridge.
890 					 */
891 					bstp_set_port_role(bp,
892 					    BSTP_ROLE_BACKUP);
893 				} else {
894 					/*
895 					 * the port is an inferior path to the
896 					 * root bridge.
897 					 */
898 					bstp_set_port_role(bp,
899 					    BSTP_ROLE_ALTERNATE);
900 				}
901 			}
902 			break;
903 		}
904 	}
905 }
906 
907 static void
908 bstp_update_state(struct bstp_state *bs, struct bstp_port *bp)
909 {
910 	struct bstp_port *bp2;
911 	int synced;
912 
913 	BSTP_LOCK_ASSERT(bs);
914 
915 	/* check if all the ports have syncronised again */
916 	if (!bs->bs_allsynced) {
917 		synced = 1;
918 		LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
919 			if (!(bp2->bp_synced ||
920 			     bp2->bp_role == BSTP_ROLE_ROOT)) {
921 				synced = 0;
922 				break;
923 			}
924 		}
925 		bs->bs_allsynced = synced;
926 	}
927 
928 	bstp_update_roles(bs, bp);
929 	bstp_update_tc(bp);
930 }
931 
932 static void
933 bstp_update_roles(struct bstp_state *bs, struct bstp_port *bp)
934 {
935 	switch (bp->bp_role) {
936 	case BSTP_ROLE_DISABLED:
937 		/* Clear any flags if set */
938 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
939 			bp->bp_sync = 0;
940 			bp->bp_synced = 1;
941 			bp->bp_reroot = 0;
942 		}
943 		break;
944 
945 	case BSTP_ROLE_ALTERNATE:
946 	case BSTP_ROLE_BACKUP:
947 		if ((bs->bs_allsynced && !bp->bp_agree) ||
948 		    (bp->bp_proposed && bp->bp_agree)) {
949 			bp->bp_proposed = 0;
950 			bp->bp_agree = 1;
951 			bp->bp_flags |= BSTP_PORT_NEWINFO;
952 			DPRINTF("%s -> ALTERNATE_AGREED\n",
953 			    bp->bp_ifp->if_xname);
954 		}
955 
956 		if (bp->bp_proposed && !bp->bp_agree) {
957 			bstp_set_all_sync(bs);
958 			bp->bp_proposed = 0;
959 			DPRINTF("%s -> ALTERNATE_PROPOSED\n",
960 			    bp->bp_ifp->if_xname);
961 		}
962 
963 		/* Clear any flags if set */
964 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
965 			bp->bp_sync = 0;
966 			bp->bp_synced = 1;
967 			bp->bp_reroot = 0;
968 			DPRINTF("%s -> ALTERNATE_PORT\n", bp->bp_ifp->if_xname);
969 		}
970 		break;
971 
972 	case BSTP_ROLE_ROOT:
973 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING && !bp->bp_reroot) {
974 			bstp_set_all_reroot(bs);
975 			DPRINTF("%s -> ROOT_REROOT\n", bp->bp_ifp->if_xname);
976 		}
977 
978 		if ((bs->bs_allsynced && !bp->bp_agree) ||
979 		    (bp->bp_proposed && bp->bp_agree)) {
980 			bp->bp_proposed = 0;
981 			bp->bp_sync = 0;
982 			bp->bp_agree = 1;
983 			bp->bp_flags |= BSTP_PORT_NEWINFO;
984 			DPRINTF("%s -> ROOT_AGREED\n", bp->bp_ifp->if_xname);
985 		}
986 
987 		if (bp->bp_proposed && !bp->bp_agree) {
988 			bstp_set_all_sync(bs);
989 			bp->bp_proposed = 0;
990 			DPRINTF("%s -> ROOT_PROPOSED\n", bp->bp_ifp->if_xname);
991 		}
992 
993 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
994 		    (bp->bp_forward_delay_timer.active == 0 ||
995 		    (bstp_rerooted(bs, bp) &&
996 		    bp->bp_recent_backup_timer.active == 0 &&
997 		    bp->bp_protover == BSTP_PROTO_RSTP))) {
998 			switch (bp->bp_state) {
999 			case BSTP_IFSTATE_DISCARDING:
1000 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
1001 				break;
1002 			case BSTP_IFSTATE_LEARNING:
1003 				bstp_set_port_state(bp,
1004 				    BSTP_IFSTATE_FORWARDING);
1005 				break;
1006 			}
1007 		}
1008 
1009 		if (bp->bp_state == BSTP_IFSTATE_FORWARDING && bp->bp_reroot) {
1010 			bp->bp_reroot = 0;
1011 			DPRINTF("%s -> ROOT_REROOTED\n", bp->bp_ifp->if_xname);
1012 		}
1013 		break;
1014 
1015 	case BSTP_ROLE_DESIGNATED:
1016 		if (bp->bp_recent_root_timer.active == 0 && bp->bp_reroot) {
1017 			bp->bp_reroot = 0;
1018 			DPRINTF("%s -> DESIGNATED_RETIRED\n",
1019 			    bp->bp_ifp->if_xname);
1020 		}
1021 
1022 		if ((bp->bp_state == BSTP_IFSTATE_DISCARDING &&
1023 		    !bp->bp_synced) || (bp->bp_agreed && !bp->bp_synced) ||
1024 		    (bp->bp_operedge && !bp->bp_synced) ||
1025 		    (bp->bp_sync && bp->bp_synced)) {
1026 			bstp_timer_stop(&bp->bp_recent_root_timer);
1027 			bp->bp_synced = 1;
1028 			bp->bp_sync = 0;
1029 			DPRINTF("%s -> DESIGNATED_SYNCED\n",
1030 			    bp->bp_ifp->if_xname);
1031 		}
1032 
1033 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1034 		    !bp->bp_agreed && !bp->bp_proposing &&
1035 		    !bp->bp_operedge) {
1036 			bp->bp_proposing = 1;
1037 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1038 			bstp_timer_start(&bp->bp_edge_delay_timer,
1039 			    (bp->bp_ptp_link ? BSTP_DEFAULT_MIGRATE_DELAY :
1040 			     bp->bp_desg_max_age));
1041 			DPRINTF("%s -> DESIGNATED_PROPOSE\n",
1042 			    bp->bp_ifp->if_xname);
1043 		}
1044 
1045 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1046 		    (bp->bp_forward_delay_timer.active == 0 || bp->bp_agreed ||
1047 		    bp->bp_operedge) &&
1048 		    (bp->bp_recent_root_timer.active == 0 || !bp->bp_reroot) &&
1049 		    !bp->bp_sync) {
1050 			if (bp->bp_agreed)
1051 				DPRINTF("%s -> AGREED\n", bp->bp_ifp->if_xname);
1052 			/*
1053 			 * If agreed|operedge then go straight to forwarding,
1054 			 * otherwise follow discard -> learn -> forward.
1055 			 */
1056 			if (bp->bp_agreed || bp->bp_operedge ||
1057 			    bp->bp_state == BSTP_IFSTATE_LEARNING) {
1058 				bstp_set_port_state(bp,
1059 				    BSTP_IFSTATE_FORWARDING);
1060 				bp->bp_agreed = bp->bp_protover;
1061 			} else if (bp->bp_state == BSTP_IFSTATE_DISCARDING)
1062 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
1063 		}
1064 
1065 		if (((bp->bp_sync && !bp->bp_synced) ||
1066 		    (bp->bp_reroot && bp->bp_recent_root_timer.active) ||
1067 		    (bp->bp_flags & BSTP_PORT_DISPUTED)) && !bp->bp_operedge &&
1068 		    bp->bp_state != BSTP_IFSTATE_DISCARDING) {
1069 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1070 			bp->bp_flags &= ~BSTP_PORT_DISPUTED;
1071 			bstp_timer_start(&bp->bp_forward_delay_timer,
1072 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1073 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1074 			DPRINTF("%s -> DESIGNATED_DISCARD\n",
1075 			    bp->bp_ifp->if_xname);
1076 		}
1077 		break;
1078 	}
1079 
1080 	if (bp->bp_flags & BSTP_PORT_NEWINFO)
1081 		bstp_transmit(bs, bp);
1082 }
1083 
1084 static void
1085 bstp_update_tc(struct bstp_port *bp)
1086 {
1087 	switch (bp->bp_tcstate) {
1088 		case BSTP_TCSTATE_ACTIVE:
1089 			if ((bp->bp_role != BSTP_ROLE_DESIGNATED &&
1090 			    bp->bp_role != BSTP_ROLE_ROOT) || bp->bp_operedge)
1091 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1092 
1093 			if (bp->bp_rcvdtcn)
1094 				bstp_set_port_tc(bp, BSTP_TCSTATE_TCN);
1095 			if (bp->bp_rcvdtc)
1096 				bstp_set_port_tc(bp, BSTP_TCSTATE_TC);
1097 
1098 			if (bp->bp_tc_prop && !bp->bp_operedge)
1099 				bstp_set_port_tc(bp, BSTP_TCSTATE_PROPAG);
1100 
1101 			if (bp->bp_rcvdtca)
1102 				bstp_set_port_tc(bp, BSTP_TCSTATE_ACK);
1103 			break;
1104 
1105 		case BSTP_TCSTATE_INACTIVE:
1106 			if ((bp->bp_state == BSTP_IFSTATE_LEARNING ||
1107 			    bp->bp_state == BSTP_IFSTATE_FORWARDING) &&
1108 			    bp->bp_fdbflush == 0)
1109 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1110 			break;
1111 
1112 		case BSTP_TCSTATE_LEARNING:
1113 			if (bp->bp_rcvdtc || bp->bp_rcvdtcn || bp->bp_rcvdtca ||
1114 			    bp->bp_tc_prop)
1115 				bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1116 			else if (bp->bp_role != BSTP_ROLE_DESIGNATED &&
1117 				 bp->bp_role != BSTP_ROLE_ROOT &&
1118 				 bp->bp_state == BSTP_IFSTATE_DISCARDING)
1119 				bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1120 
1121 			if ((bp->bp_role == BSTP_ROLE_DESIGNATED ||
1122 			    bp->bp_role == BSTP_ROLE_ROOT) &&
1123 			    bp->bp_state == BSTP_IFSTATE_FORWARDING &&
1124 			    !bp->bp_operedge)
1125 				bstp_set_port_tc(bp, BSTP_TCSTATE_DETECTED);
1126 			break;
1127 
1128 		/* these are transient states and go straight back to ACTIVE */
1129 		case BSTP_TCSTATE_DETECTED:
1130 		case BSTP_TCSTATE_TCN:
1131 		case BSTP_TCSTATE_TC:
1132 		case BSTP_TCSTATE_PROPAG:
1133 		case BSTP_TCSTATE_ACK:
1134 			DPRINTF("Invalid TC state for %s\n",
1135 			    bp->bp_ifp->if_xname);
1136 			break;
1137 	}
1138 
1139 }
1140 
1141 static void
1142 bstp_update_info(struct bstp_port *bp)
1143 {
1144 	struct bstp_state *bs = bp->bp_bs;
1145 
1146 	bp->bp_proposing = 0;
1147 	bp->bp_proposed = 0;
1148 
1149 	if (bp->bp_agreed && !bstp_pdu_bettersame(bp, BSTP_INFO_MINE))
1150 		bp->bp_agreed = 0;
1151 
1152 	if (bp->bp_synced && !bp->bp_agreed) {
1153 		bp->bp_synced = 0;
1154 		bs->bs_allsynced = 0;
1155 	}
1156 
1157 	/* copy the designated pv to the port */
1158 	bp->bp_port_pv = bp->bp_desg_pv;
1159 	bp->bp_port_msg_age = bp->bp_desg_msg_age;
1160 	bp->bp_port_max_age = bp->bp_desg_max_age;
1161 	bp->bp_port_fdelay = bp->bp_desg_fdelay;
1162 	bp->bp_port_htime = bp->bp_desg_htime;
1163 	bp->bp_infois = BSTP_INFO_MINE;
1164 
1165 	/* Set transmit flag but do not immediately send */
1166 	bp->bp_flags |= BSTP_PORT_NEWINFO;
1167 }
1168 
1169 /* set tcprop on every port other than the caller */
1170 static void
1171 bstp_set_other_tcprop(struct bstp_port *bp)
1172 {
1173 	struct bstp_state *bs = bp->bp_bs;
1174 	struct bstp_port *bp2;
1175 
1176 	BSTP_LOCK_ASSERT(bs);
1177 
1178 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1179 		if (bp2 == bp)
1180 			continue;
1181 		bp2->bp_tc_prop = 1;
1182 	}
1183 }
1184 
1185 static void
1186 bstp_set_all_reroot(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_reroot = 1;
1194 }
1195 
1196 static void
1197 bstp_set_all_sync(struct bstp_state *bs)
1198 {
1199 	struct bstp_port *bp;
1200 
1201 	BSTP_LOCK_ASSERT(bs);
1202 
1203 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1204 		bp->bp_sync = 1;
1205 		bp->bp_synced = 0;	/* Not explicit in spec */
1206 	}
1207 
1208 	bs->bs_allsynced = 0;
1209 }
1210 
1211 static void
1212 bstp_set_port_state(struct bstp_port *bp, int state)
1213 {
1214 	if (bp->bp_state == state)
1215 		return;
1216 
1217 	bp->bp_state = state;
1218 
1219 	switch (bp->bp_state) {
1220 		case BSTP_IFSTATE_DISCARDING:
1221 			DPRINTF("state changed to DISCARDING on %s\n",
1222 			    bp->bp_ifp->if_xname);
1223 			break;
1224 
1225 		case BSTP_IFSTATE_LEARNING:
1226 			DPRINTF("state changed to LEARNING on %s\n",
1227 			    bp->bp_ifp->if_xname);
1228 
1229 			bstp_timer_start(&bp->bp_forward_delay_timer,
1230 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1231 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1232 			break;
1233 
1234 		case BSTP_IFSTATE_FORWARDING:
1235 			DPRINTF("state changed to FORWARDING on %s\n",
1236 			    bp->bp_ifp->if_xname);
1237 
1238 			bstp_timer_stop(&bp->bp_forward_delay_timer);
1239 			/* Record that we enabled forwarding */
1240 			bp->bp_forward_transitions++;
1241 			break;
1242 	}
1243 
1244 	/* notify the parent bridge */
1245 	taskqueue_enqueue(taskqueue_swi, &bp->bp_statetask);
1246 }
1247 
1248 static void
1249 bstp_set_port_role(struct bstp_port *bp, int role)
1250 {
1251 	struct bstp_state *bs = bp->bp_bs;
1252 
1253 	if (bp->bp_role == role)
1254 		return;
1255 
1256 	/* perform pre-change tasks */
1257 	switch (bp->bp_role) {
1258 		case BSTP_ROLE_DISABLED:
1259 			bstp_timer_start(&bp->bp_forward_delay_timer,
1260 			    bp->bp_desg_max_age);
1261 			break;
1262 
1263 		case BSTP_ROLE_BACKUP:
1264 			bstp_timer_start(&bp->bp_recent_backup_timer,
1265 			    bp->bp_desg_htime * 2);
1266 			/* fall through */
1267 		case BSTP_ROLE_ALTERNATE:
1268 			bstp_timer_start(&bp->bp_forward_delay_timer,
1269 			    bp->bp_desg_fdelay);
1270 			bp->bp_sync = 0;
1271 			bp->bp_synced = 1;
1272 			bp->bp_reroot = 0;
1273 			break;
1274 
1275 		case BSTP_ROLE_ROOT:
1276 			bstp_timer_start(&bp->bp_recent_root_timer,
1277 			    BSTP_DEFAULT_FORWARD_DELAY);
1278 			break;
1279 	}
1280 
1281 	bp->bp_role = role;
1282 	/* clear values not carried between roles */
1283 	bp->bp_proposing = 0;
1284 	bs->bs_allsynced = 0;
1285 
1286 	/* initialise the new role */
1287 	switch (bp->bp_role) {
1288 		case BSTP_ROLE_DISABLED:
1289 		case BSTP_ROLE_ALTERNATE:
1290 		case BSTP_ROLE_BACKUP:
1291 			DPRINTF("%s role -> ALT/BACK/DISABLED\n",
1292 			    bp->bp_ifp->if_xname);
1293 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1294 			bstp_timer_stop(&bp->bp_recent_root_timer);
1295 			bstp_timer_latch(&bp->bp_forward_delay_timer);
1296 			bp->bp_sync = 0;
1297 			bp->bp_synced = 1;
1298 			bp->bp_reroot = 0;
1299 			break;
1300 
1301 		case BSTP_ROLE_ROOT:
1302 			DPRINTF("%s role -> ROOT\n",
1303 			    bp->bp_ifp->if_xname);
1304 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1305 			bstp_timer_latch(&bp->bp_recent_root_timer);
1306 			bp->bp_proposing = 0;
1307 			break;
1308 
1309 		case BSTP_ROLE_DESIGNATED:
1310 			DPRINTF("%s role -> DESIGNATED\n",
1311 			    bp->bp_ifp->if_xname);
1312 			bstp_timer_start(&bp->bp_hello_timer,
1313 			    bp->bp_desg_htime);
1314 			bp->bp_agree = 0;
1315 			break;
1316 	}
1317 
1318 	/* let the TC state know that the role changed */
1319 	bstp_update_tc(bp);
1320 }
1321 
1322 static void
1323 bstp_set_port_proto(struct bstp_port *bp, int proto)
1324 {
1325 	struct bstp_state *bs = bp->bp_bs;
1326 
1327 	/* supported protocol versions */
1328 	switch (proto) {
1329 		case BSTP_PROTO_STP:
1330 			/* we can downgrade protocols only */
1331 			bstp_timer_stop(&bp->bp_migrate_delay_timer);
1332 			/* clear unsupported features */
1333 			bp->bp_operedge = 0;
1334 			/* STP compat mode only uses 16 bits of the 32 */
1335 			if (bp->bp_path_cost > 65535)
1336 				bp->bp_path_cost = 65535;
1337 			break;
1338 
1339 		case BSTP_PROTO_RSTP:
1340 			bstp_timer_start(&bp->bp_migrate_delay_timer,
1341 			    bs->bs_migration_delay);
1342 			break;
1343 
1344 		default:
1345 			DPRINTF("Unsupported STP version %d\n", proto);
1346 			return;
1347 	}
1348 
1349 	bp->bp_protover = proto;
1350 	bp->bp_flags &= ~BSTP_PORT_CANMIGRATE;
1351 }
1352 
1353 static void
1354 bstp_set_port_tc(struct bstp_port *bp, int state)
1355 {
1356 	struct bstp_state *bs = bp->bp_bs;
1357 
1358 	bp->bp_tcstate = state;
1359 
1360 	/* initialise the new state */
1361 	switch (bp->bp_tcstate) {
1362 		case BSTP_TCSTATE_ACTIVE:
1363 			DPRINTF("%s -> TC_ACTIVE\n", bp->bp_ifp->if_xname);
1364 			/* nothing to do */
1365 			break;
1366 
1367 		case BSTP_TCSTATE_INACTIVE:
1368 			bstp_timer_stop(&bp->bp_tc_timer);
1369 			/* flush routes on the parent bridge */
1370 			bp->bp_fdbflush = 1;
1371 			taskqueue_enqueue(taskqueue_swi, &bp->bp_rtagetask);
1372 			bp->bp_tc_ack = 0;
1373 			DPRINTF("%s -> TC_INACTIVE\n", bp->bp_ifp->if_xname);
1374 			break;
1375 
1376 		case BSTP_TCSTATE_LEARNING:
1377 			bp->bp_rcvdtc = 0;
1378 			bp->bp_rcvdtcn = 0;
1379 			bp->bp_rcvdtca = 0;
1380 			bp->bp_tc_prop = 0;
1381 			DPRINTF("%s -> TC_LEARNING\n", bp->bp_ifp->if_xname);
1382 			break;
1383 
1384 		case BSTP_TCSTATE_DETECTED:
1385 			bstp_set_timer_tc(bp);
1386 			bstp_set_other_tcprop(bp);
1387 			/* send out notification */
1388 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1389 			bstp_transmit(bs, bp);
1390 			getmicrotime(&bs->bs_last_tc_time);
1391 			DPRINTF("%s -> TC_DETECTED\n", bp->bp_ifp->if_xname);
1392 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1393 			break;
1394 
1395 		case BSTP_TCSTATE_TCN:
1396 			bstp_set_timer_tc(bp);
1397 			DPRINTF("%s -> TC_TCN\n", bp->bp_ifp->if_xname);
1398 			/* fall through */
1399 		case BSTP_TCSTATE_TC:
1400 			bp->bp_rcvdtc = 0;
1401 			bp->bp_rcvdtcn = 0;
1402 			if (bp->bp_role == BSTP_ROLE_DESIGNATED)
1403 				bp->bp_tc_ack = 1;
1404 
1405 			bstp_set_other_tcprop(bp);
1406 			DPRINTF("%s -> TC_TC\n", bp->bp_ifp->if_xname);
1407 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1408 			break;
1409 
1410 		case BSTP_TCSTATE_PROPAG:
1411 			/* flush routes on the parent bridge */
1412 			bp->bp_fdbflush = 1;
1413 			taskqueue_enqueue(taskqueue_swi, &bp->bp_rtagetask);
1414 			bp->bp_tc_prop = 0;
1415 			bstp_set_timer_tc(bp);
1416 			DPRINTF("%s -> TC_PROPAG\n", bp->bp_ifp->if_xname);
1417 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1418 			break;
1419 
1420 		case BSTP_TCSTATE_ACK:
1421 			bstp_timer_stop(&bp->bp_tc_timer);
1422 			bp->bp_rcvdtca = 0;
1423 			DPRINTF("%s -> TC_ACK\n", bp->bp_ifp->if_xname);
1424 			bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1425 			break;
1426 	}
1427 }
1428 
1429 static void
1430 bstp_set_timer_tc(struct bstp_port *bp)
1431 {
1432 	struct bstp_state *bs = bp->bp_bs;
1433 
1434 	if (bp->bp_tc_timer.active)
1435 		return;
1436 
1437 	switch (bp->bp_protover) {
1438 		case BSTP_PROTO_RSTP:
1439 			bstp_timer_start(&bp->bp_tc_timer,
1440 			    bp->bp_desg_htime + BSTP_TICK_VAL);
1441 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1442 			break;
1443 
1444 		case BSTP_PROTO_STP:
1445 			bstp_timer_start(&bp->bp_tc_timer,
1446 			    bs->bs_root_max_age + bs->bs_root_fdelay);
1447 			break;
1448 	}
1449 }
1450 
1451 static void
1452 bstp_set_timer_msgage(struct bstp_port *bp)
1453 {
1454 	if (bp->bp_port_msg_age + BSTP_MESSAGE_AGE_INCR <=
1455 	    bp->bp_port_max_age) {
1456 		bstp_timer_start(&bp->bp_message_age_timer,
1457 		    bp->bp_port_htime * 3);
1458 	} else
1459 		/* expires immediately */
1460 		bstp_timer_start(&bp->bp_message_age_timer, 0);
1461 }
1462 
1463 static int
1464 bstp_rerooted(struct bstp_state *bs, struct bstp_port *bp)
1465 {
1466 	struct bstp_port *bp2;
1467 	int rr_set = 0;
1468 
1469 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1470 		if (bp2 == bp)
1471 			continue;
1472 		if (bp2->bp_recent_root_timer.active) {
1473 			rr_set = 1;
1474 			break;
1475 		}
1476 	}
1477 	return (!rr_set);
1478 }
1479 
1480 int
1481 bstp_set_htime(struct bstp_state *bs, int t)
1482 {
1483 	/* convert seconds to ticks */
1484 	t *=  BSTP_TICK_VAL;
1485 
1486 	/* value can only be changed in leagacy stp mode */
1487 	if (bs->bs_protover != BSTP_PROTO_STP)
1488 		return (EPERM);
1489 
1490 	if (t < BSTP_MIN_HELLO_TIME || t > BSTP_MAX_HELLO_TIME)
1491 		return (EINVAL);
1492 
1493 	BSTP_LOCK(bs);
1494 	bs->bs_bridge_htime = t;
1495 	bstp_reinit(bs);
1496 	BSTP_UNLOCK(bs);
1497 	return (0);
1498 }
1499 
1500 int
1501 bstp_set_fdelay(struct bstp_state *bs, int t)
1502 {
1503 	/* convert seconds to ticks */
1504 	t *= BSTP_TICK_VAL;
1505 
1506 	if (t < BSTP_MIN_FORWARD_DELAY || t > BSTP_MAX_FORWARD_DELAY)
1507 		return (EINVAL);
1508 
1509 	BSTP_LOCK(bs);
1510 	bs->bs_bridge_fdelay = t;
1511 	bstp_reinit(bs);
1512 	BSTP_UNLOCK(bs);
1513 	return (0);
1514 }
1515 
1516 int
1517 bstp_set_maxage(struct bstp_state *bs, int t)
1518 {
1519 	/* convert seconds to ticks */
1520 	t *= BSTP_TICK_VAL;
1521 
1522 	if (t < BSTP_MIN_MAX_AGE || t > BSTP_MAX_MAX_AGE)
1523 		return (EINVAL);
1524 
1525 	BSTP_LOCK(bs);
1526 	bs->bs_bridge_max_age = t;
1527 	bstp_reinit(bs);
1528 	BSTP_UNLOCK(bs);
1529 	return (0);
1530 }
1531 
1532 int
1533 bstp_set_holdcount(struct bstp_state *bs, int count)
1534 {
1535 	struct bstp_port *bp;
1536 
1537 	if (count < BSTP_MIN_HOLD_COUNT ||
1538 	    count > BSTP_MAX_HOLD_COUNT)
1539 		return (EINVAL);
1540 
1541 	BSTP_LOCK(bs);
1542 	bs->bs_txholdcount = count;
1543 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1544 		bp->bp_txcount = 0;
1545 	BSTP_UNLOCK(bs);
1546 	return (0);
1547 }
1548 
1549 int
1550 bstp_set_protocol(struct bstp_state *bs, int proto)
1551 {
1552 	struct bstp_port *bp;
1553 
1554 	switch (proto) {
1555 		/* Supported protocol versions */
1556 		case BSTP_PROTO_STP:
1557 		case BSTP_PROTO_RSTP:
1558 			break;
1559 
1560 		default:
1561 			return (EINVAL);
1562 	}
1563 
1564 	BSTP_LOCK(bs);
1565 	bs->bs_protover = proto;
1566 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
1567 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1568 		/* reinit state */
1569 		bp->bp_infois = BSTP_INFO_DISABLED;
1570 		bp->bp_txcount = 0;
1571 		bstp_set_port_proto(bp, bs->bs_protover);
1572 		bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
1573 		bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1574 		bstp_timer_stop(&bp->bp_recent_backup_timer);
1575 	}
1576 	bstp_reinit(bs);
1577 	BSTP_UNLOCK(bs);
1578 	return (0);
1579 }
1580 
1581 int
1582 bstp_set_priority(struct bstp_state *bs, int pri)
1583 {
1584 	if (pri < 0 || pri > BSTP_MAX_PRIORITY)
1585 		return (EINVAL);
1586 
1587 	/* Limit to steps of 4096 */
1588 	pri -= pri % 4096;
1589 
1590 	BSTP_LOCK(bs);
1591 	bs->bs_bridge_priority = pri;
1592 	bstp_reinit(bs);
1593 	BSTP_UNLOCK(bs);
1594 	return (0);
1595 }
1596 
1597 int
1598 bstp_set_port_priority(struct bstp_port *bp, int pri)
1599 {
1600 	struct bstp_state *bs = bp->bp_bs;
1601 
1602 	if (pri < 0 || pri > BSTP_MAX_PORT_PRIORITY)
1603 		return (EINVAL);
1604 
1605 	/* Limit to steps of 16 */
1606 	pri -= pri % 16;
1607 
1608 	BSTP_LOCK(bs);
1609 	bp->bp_priority = pri;
1610 	bstp_reinit(bs);
1611 	BSTP_UNLOCK(bs);
1612 	return (0);
1613 }
1614 
1615 int
1616 bstp_set_path_cost(struct bstp_port *bp, uint32_t path_cost)
1617 {
1618 	struct bstp_state *bs = bp->bp_bs;
1619 
1620 	if (path_cost > BSTP_MAX_PATH_COST)
1621 		return (EINVAL);
1622 
1623 	/* STP compat mode only uses 16 bits of the 32 */
1624 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1625 		path_cost = 65535;
1626 
1627 	BSTP_LOCK(bs);
1628 
1629 	if (path_cost == 0) {	/* use auto */
1630 		bp->bp_flags &= ~BSTP_PORT_ADMCOST;
1631 		bp->bp_path_cost = bstp_calc_path_cost(bp);
1632 	} else {
1633 		bp->bp_path_cost = path_cost;
1634 		bp->bp_flags |= BSTP_PORT_ADMCOST;
1635 	}
1636 	bstp_reinit(bs);
1637 	BSTP_UNLOCK(bs);
1638 	return (0);
1639 }
1640 
1641 int
1642 bstp_set_edge(struct bstp_port *bp, int set)
1643 {
1644 	struct bstp_state *bs = bp->bp_bs;
1645 
1646 	BSTP_LOCK(bs);
1647 	if ((bp->bp_operedge = set) == 0)
1648 		bp->bp_flags &= ~BSTP_PORT_ADMEDGE;
1649 	else
1650 		bp->bp_flags |= BSTP_PORT_ADMEDGE;
1651 	BSTP_UNLOCK(bs);
1652 	return (0);
1653 }
1654 
1655 int
1656 bstp_set_autoedge(struct bstp_port *bp, int set)
1657 {
1658 	struct bstp_state *bs = bp->bp_bs;
1659 
1660 	BSTP_LOCK(bs);
1661 	if (set) {
1662 		bp->bp_flags |= BSTP_PORT_AUTOEDGE;
1663 		/* we may be able to transition straight to edge */
1664 		if (bp->bp_edge_delay_timer.active == 0)
1665 			bstp_edge_delay_expiry(bs, bp);
1666 	} else
1667 		bp->bp_flags &= ~BSTP_PORT_AUTOEDGE;
1668 	BSTP_UNLOCK(bs);
1669 	return (0);
1670 }
1671 
1672 int
1673 bstp_set_ptp(struct bstp_port *bp, int set)
1674 {
1675 	struct bstp_state *bs = bp->bp_bs;
1676 
1677 	BSTP_LOCK(bs);
1678 	bp->bp_ptp_link = set;
1679 	BSTP_UNLOCK(bs);
1680 	return (0);
1681 }
1682 
1683 int
1684 bstp_set_autoptp(struct bstp_port *bp, int set)
1685 {
1686 	struct bstp_state *bs = bp->bp_bs;
1687 
1688 	BSTP_LOCK(bs);
1689 	if (set) {
1690 		bp->bp_flags |= BSTP_PORT_AUTOPTP;
1691 		if (bp->bp_role != BSTP_ROLE_DISABLED)
1692 			bstp_ifupdstatus(bs, bp);
1693 	} else
1694 		bp->bp_flags &= ~BSTP_PORT_AUTOPTP;
1695 	BSTP_UNLOCK(bs);
1696 	return (0);
1697 }
1698 
1699 /*
1700  * Calculate the path cost according to the link speed.
1701  */
1702 static uint32_t
1703 bstp_calc_path_cost(struct bstp_port *bp)
1704 {
1705 	struct ifnet *ifp = bp->bp_ifp;
1706 	uint32_t path_cost;
1707 
1708 	/* If the priority has been manually set then retain the value */
1709 	if (bp->bp_flags & BSTP_PORT_ADMCOST)
1710 		return bp->bp_path_cost;
1711 
1712 	if (ifp->if_link_state == LINK_STATE_DOWN) {
1713 		/* Recalc when the link comes up again */
1714 		bp->bp_flags |= BSTP_PORT_PNDCOST;
1715 		return (BSTP_DEFAULT_PATH_COST);
1716 	}
1717 
1718 	if (ifp->if_baudrate < 1000)
1719 		return (BSTP_DEFAULT_PATH_COST);
1720 
1721  	/* formula from section 17.14, IEEE Std 802.1D-2004 */
1722 	path_cost = 20000000000ULL / (ifp->if_baudrate / 1000);
1723 
1724 	if (path_cost > BSTP_MAX_PATH_COST)
1725 		path_cost = BSTP_MAX_PATH_COST;
1726 
1727 	/* STP compat mode only uses 16 bits of the 32 */
1728 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1729 		path_cost = 65535;
1730 
1731 	return (path_cost);
1732 }
1733 
1734 /*
1735  * Notify the bridge that a port state has changed, we need to do this from a
1736  * taskqueue to avoid a LOR.
1737  */
1738 static void
1739 bstp_notify_state(void *arg, int pending)
1740 {
1741 	struct bstp_port *bp = (struct bstp_port *)arg;
1742 	struct bstp_state *bs = bp->bp_bs;
1743 
1744 	if (bp->bp_active == 1 && bs->bs_state_cb != NULL)
1745 		(*bs->bs_state_cb)(bp->bp_ifp, bp->bp_state);
1746 }
1747 
1748 /*
1749  * Flush the routes on the bridge port, we need to do this from a
1750  * taskqueue to avoid a LOR.
1751  */
1752 static void
1753 bstp_notify_rtage(void *arg, int pending)
1754 {
1755 	struct bstp_port *bp = (struct bstp_port *)arg;
1756 	struct bstp_state *bs = bp->bp_bs;
1757 	int age = 0;
1758 
1759 	BSTP_LOCK(bs);
1760 	switch (bp->bp_protover) {
1761 		case BSTP_PROTO_STP:
1762 			/* convert to seconds */
1763 			age = bp->bp_desg_fdelay / BSTP_TICK_VAL;
1764 			break;
1765 
1766 		case BSTP_PROTO_RSTP:
1767 			age = 0;
1768 			break;
1769 	}
1770 	BSTP_UNLOCK(bs);
1771 
1772 	if (bp->bp_active == 1 && bs->bs_rtage_cb != NULL)
1773 		(*bs->bs_rtage_cb)(bp->bp_ifp, age);
1774 
1775 	/* flush is complete */
1776 	BSTP_LOCK(bs);
1777 	bp->bp_fdbflush = 0;
1778 	BSTP_UNLOCK(bs);
1779 }
1780 
1781 void
1782 bstp_linkstate(struct ifnet *ifp, int state)
1783 {
1784 	struct bstp_state *bs;
1785 	struct bstp_port *bp;
1786 
1787 	/* search for the stp port */
1788 	mtx_lock(&bstp_list_mtx);
1789 	LIST_FOREACH(bs, &bstp_list, bs_list) {
1790 		BSTP_LOCK(bs);
1791 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1792 			if (bp->bp_ifp == ifp) {
1793 				bstp_ifupdstatus(bs, bp);
1794 				bstp_update_state(bs, bp);
1795 				/* it only exists once so return */
1796 				BSTP_UNLOCK(bs);
1797 				mtx_unlock(&bstp_list_mtx);
1798 				return;
1799 			}
1800 		}
1801 		BSTP_UNLOCK(bs);
1802 	}
1803 	mtx_unlock(&bstp_list_mtx);
1804 }
1805 
1806 static void
1807 bstp_ifupdstatus(struct bstp_state *bs, struct bstp_port *bp)
1808 {
1809 	struct ifnet *ifp = bp->bp_ifp;
1810 	struct ifmediareq ifmr;
1811 	int error = 0;
1812 
1813 	BSTP_LOCK_ASSERT(bs);
1814 
1815 	bzero((char *)&ifmr, sizeof(ifmr));
1816 	error = (*ifp->if_ioctl)(ifp, SIOCGIFMEDIA, (caddr_t)&ifmr);
1817 
1818 	if ((error == 0) && (ifp->if_flags & IFF_UP)) {
1819 		if (ifmr.ifm_status & IFM_ACTIVE) {
1820 			/* A full-duplex link is assumed to be point to point */
1821 			if (bp->bp_flags & BSTP_PORT_AUTOPTP) {
1822 				bp->bp_ptp_link =
1823 				    ifmr.ifm_active & IFM_FDX ? 1 : 0;
1824 			}
1825 
1826 			/* Calc the cost if the link was down previously */
1827 			if (bp->bp_flags & BSTP_PORT_PNDCOST) {
1828 				bp->bp_path_cost = bstp_calc_path_cost(bp);
1829 				bp->bp_flags &= ~BSTP_PORT_PNDCOST;
1830 			}
1831 
1832 			if (bp->bp_role == BSTP_ROLE_DISABLED)
1833 				bstp_enable_port(bs, bp);
1834 		} else {
1835 			if (bp->bp_role != BSTP_ROLE_DISABLED) {
1836 				bstp_disable_port(bs, bp);
1837 				if ((bp->bp_flags & BSTP_PORT_ADMEDGE) &&
1838 				    bp->bp_protover == BSTP_PROTO_RSTP)
1839 					bp->bp_operedge = 1;
1840 			}
1841 		}
1842 		return;
1843 	}
1844 
1845 	if (bp->bp_infois != BSTP_INFO_DISABLED)
1846 		bstp_disable_port(bs, bp);
1847 }
1848 
1849 static void
1850 bstp_enable_port(struct bstp_state *bs, struct bstp_port *bp)
1851 {
1852 	bp->bp_infois = BSTP_INFO_AGED;
1853 	bstp_assign_roles(bs);
1854 }
1855 
1856 static void
1857 bstp_disable_port(struct bstp_state *bs, struct bstp_port *bp)
1858 {
1859 	bp->bp_infois = BSTP_INFO_DISABLED;
1860 	bstp_assign_roles(bs);
1861 }
1862 
1863 static void
1864 bstp_tick(void *arg)
1865 {
1866 	struct bstp_state *bs = arg;
1867 	struct bstp_port *bp;
1868 
1869 	BSTP_LOCK_ASSERT(bs);
1870 
1871 	if (bs->bs_running == 0)
1872 		return;
1873 
1874 	/* slow timer to catch missed link events */
1875 	if (bstp_timer_expired(&bs->bs_link_timer)) {
1876 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1877 			bstp_ifupdstatus(bs, bp);
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_expired(&bp->bp_tc_timer);
1884 		bstp_timer_expired(&bp->bp_recent_root_timer);
1885 		bstp_timer_expired(&bp->bp_forward_delay_timer);
1886 		bstp_timer_expired(&bp->bp_recent_backup_timer);
1887 
1888 		if (bstp_timer_expired(&bp->bp_hello_timer))
1889 			bstp_hello_timer_expiry(bs, bp);
1890 
1891 		if (bstp_timer_expired(&bp->bp_message_age_timer))
1892 			bstp_message_age_expiry(bs, bp);
1893 
1894 		if (bstp_timer_expired(&bp->bp_migrate_delay_timer))
1895 			bstp_migrate_delay_expiry(bs, bp);
1896 
1897 		if (bstp_timer_expired(&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 	callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
1908 }
1909 
1910 static void
1911 bstp_timer_start(struct bstp_timer *t, uint16_t v)
1912 {
1913 	t->value = v;
1914 	t->active = 1;
1915 	t->latched = 0;
1916 }
1917 
1918 static void
1919 bstp_timer_stop(struct bstp_timer *t)
1920 {
1921 	t->value = 0;
1922 	t->active = 0;
1923 	t->latched = 0;
1924 }
1925 
1926 static void
1927 bstp_timer_latch(struct bstp_timer *t)
1928 {
1929 	t->latched = 1;
1930 	t->active = 1;
1931 }
1932 
1933 static int
1934 bstp_timer_expired(struct bstp_timer *t)
1935 {
1936 	if (t->active == 0 || t->latched)
1937 		return (0);
1938 	t->value -= BSTP_TICK_VAL;
1939 	if (t->value <= 0) {
1940 		bstp_timer_stop(t);
1941 		return (1);
1942 	}
1943 	return (0);
1944 }
1945 
1946 static void
1947 bstp_hello_timer_expiry(struct bstp_state *bs, struct bstp_port *bp)
1948 {
1949 	if ((bp->bp_flags & BSTP_PORT_NEWINFO) ||
1950 	    bp->bp_role == BSTP_ROLE_DESIGNATED ||
1951 	    (bp->bp_role == BSTP_ROLE_ROOT &&
1952 	     bp->bp_tc_timer.active == 1)) {
1953 		bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
1954 		bp->bp_flags |= BSTP_PORT_NEWINFO;
1955 		bstp_transmit(bs, bp);
1956 	}
1957 }
1958 
1959 static void
1960 bstp_message_age_expiry(struct bstp_state *bs, struct bstp_port *bp)
1961 {
1962 	if (bp->bp_infois == BSTP_INFO_RECEIVED) {
1963 		bp->bp_infois = BSTP_INFO_AGED;
1964 		bstp_assign_roles(bs);
1965 		DPRINTF("aged info on %s\n", bp->bp_ifp->if_xname);
1966 	}
1967 }
1968 
1969 static void
1970 bstp_migrate_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1971 {
1972 	bp->bp_flags |= BSTP_PORT_CANMIGRATE;
1973 }
1974 
1975 static void
1976 bstp_edge_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1977 {
1978 	if ((bp->bp_flags & BSTP_PORT_AUTOEDGE) &&
1979 	    bp->bp_protover == BSTP_PROTO_RSTP && bp->bp_proposing &&
1980 	    bp->bp_role == BSTP_ROLE_DESIGNATED) {
1981 		bp->bp_operedge = 1;
1982 		DPRINTF("%s -> edge port\n", bp->bp_ifp->if_xname);
1983 	}
1984 }
1985 
1986 static int
1987 bstp_addr_cmp(const uint8_t *a, const uint8_t *b)
1988 {
1989 	int i, d;
1990 
1991 	for (i = 0, d = 0; i < ETHER_ADDR_LEN && d == 0; i++) {
1992 		d = ((int)a[i]) - ((int)b[i]);
1993 	}
1994 
1995 	return (d);
1996 }
1997 
1998 /*
1999  * compare the bridge address component of the bridgeid
2000  */
2001 static int
2002 bstp_same_bridgeid(uint64_t id1, uint64_t id2)
2003 {
2004 	u_char addr1[ETHER_ADDR_LEN];
2005 	u_char addr2[ETHER_ADDR_LEN];
2006 
2007 	PV2ADDR(id1, addr1);
2008 	PV2ADDR(id2, addr2);
2009 
2010 	if (bstp_addr_cmp(addr1, addr2) == 0)
2011 		return (1);
2012 
2013 	return (0);
2014 }
2015 
2016 void
2017 bstp_reinit(struct bstp_state *bs)
2018 {
2019 	struct bstp_port *bp;
2020 	struct ifnet *ifp, *mif;
2021 	u_char *e_addr;
2022 	static const u_char llzero[ETHER_ADDR_LEN];	/* 00:00:00:00:00:00 */
2023 
2024 	BSTP_LOCK_ASSERT(bs);
2025 
2026 	mif = NULL;
2027 	/*
2028 	 * Search through the Ethernet adapters and find the one with the
2029 	 * lowest value. The adapter which we take the MAC address from does
2030 	 * not need to be part of the bridge, it just needs to be a unique
2031 	 * value.
2032 	 */
2033 	IFNET_RLOCK();
2034 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
2035 		if (ifp->if_type != IFT_ETHER)
2036 			continue;
2037 
2038 		if (bstp_addr_cmp(IF_LLADDR(ifp), llzero) == 0)
2039 			continue;
2040 
2041 		if (mif == NULL) {
2042 			mif = ifp;
2043 			continue;
2044 		}
2045 		if (bstp_addr_cmp(IF_LLADDR(ifp), IF_LLADDR(mif)) < 0) {
2046 			mif = ifp;
2047 			continue;
2048 		}
2049 	}
2050 	IFNET_RUNLOCK();
2051 
2052 	if (LIST_EMPTY(&bs->bs_bplist) || mif == NULL) {
2053 		/* Set the bridge and root id (lower bits) to zero */
2054 		bs->bs_bridge_pv.pv_dbridge_id =
2055 		    ((uint64_t)bs->bs_bridge_priority) << 48;
2056 		bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
2057 		bs->bs_root_pv = bs->bs_bridge_pv;
2058 		/* Disable any remaining ports, they will have no MAC address */
2059 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2060 			bp->bp_infois = BSTP_INFO_DISABLED;
2061 			bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2062 		}
2063 		callout_stop(&bs->bs_bstpcallout);
2064 		return;
2065 	}
2066 
2067 	e_addr = IF_LLADDR(mif);
2068 	bs->bs_bridge_pv.pv_dbridge_id =
2069 	    (((uint64_t)bs->bs_bridge_priority) << 48) |
2070 	    (((uint64_t)e_addr[0]) << 40) |
2071 	    (((uint64_t)e_addr[1]) << 32) |
2072 	    (((uint64_t)e_addr[2]) << 24) |
2073 	    (((uint64_t)e_addr[3]) << 16) |
2074 	    (((uint64_t)e_addr[4]) << 8) |
2075 	    (((uint64_t)e_addr[5]));
2076 
2077 	bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
2078 	bs->bs_bridge_pv.pv_cost = 0;
2079 	bs->bs_bridge_pv.pv_dport_id = 0;
2080 	bs->bs_bridge_pv.pv_port_id = 0;
2081 
2082 	if (bs->bs_running && callout_pending(&bs->bs_bstpcallout) == 0)
2083 		callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
2084 
2085 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2086 		bp->bp_port_id = (bp->bp_priority << 8) |
2087 		    (bp->bp_ifp->if_index  & 0xfff);
2088 		bstp_ifupdstatus(bs, bp);
2089 	}
2090 
2091 	bstp_assign_roles(bs);
2092 	bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
2093 }
2094 
2095 static int
2096 bstp_modevent(module_t mod, int type, void *data)
2097 {
2098 	switch (type) {
2099 	case MOD_LOAD:
2100 		mtx_init(&bstp_list_mtx, "bridgestp list", NULL, MTX_DEF);
2101 		LIST_INIT(&bstp_list);
2102 		bstp_linkstate_p = bstp_linkstate;
2103 		break;
2104 	case MOD_UNLOAD:
2105 		bstp_linkstate_p = NULL;
2106 		mtx_destroy(&bstp_list_mtx);
2107 		break;
2108 	default:
2109 		return (EOPNOTSUPP);
2110 	}
2111 	return (0);
2112 }
2113 
2114 static moduledata_t bstp_mod = {
2115 	"bridgestp",
2116 	bstp_modevent,
2117 	0
2118 };
2119 
2120 DECLARE_MODULE(bridgestp, bstp_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
2121 MODULE_VERSION(bridgestp, 1);
2122 
2123 void
2124 bstp_attach(struct bstp_state *bs, struct bstp_cb_ops *cb)
2125 {
2126 	BSTP_LOCK_INIT(bs);
2127 	callout_init_mtx(&bs->bs_bstpcallout, &bs->bs_mtx, 0);
2128 	LIST_INIT(&bs->bs_bplist);
2129 
2130 	bs->bs_bridge_max_age = BSTP_DEFAULT_MAX_AGE;
2131 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
2132 	bs->bs_bridge_fdelay = BSTP_DEFAULT_FORWARD_DELAY;
2133 	bs->bs_bridge_priority = BSTP_DEFAULT_BRIDGE_PRIORITY;
2134 	bs->bs_hold_time = BSTP_DEFAULT_HOLD_TIME;
2135 	bs->bs_migration_delay = BSTP_DEFAULT_MIGRATE_DELAY;
2136 	bs->bs_txholdcount = BSTP_DEFAULT_HOLD_COUNT;
2137 	bs->bs_protover = BSTP_PROTO_RSTP;
2138 	bs->bs_state_cb = cb->bcb_state;
2139 	bs->bs_rtage_cb = cb->bcb_rtage;
2140 
2141 	getmicrotime(&bs->bs_last_tc_time);
2142 
2143 	mtx_lock(&bstp_list_mtx);
2144 	LIST_INSERT_HEAD(&bstp_list, bs, bs_list);
2145 	mtx_unlock(&bstp_list_mtx);
2146 }
2147 
2148 void
2149 bstp_detach(struct bstp_state *bs)
2150 {
2151 	KASSERT(LIST_EMPTY(&bs->bs_bplist), ("bstp still active"));
2152 
2153 	mtx_lock(&bstp_list_mtx);
2154 	LIST_REMOVE(bs, bs_list);
2155 	mtx_unlock(&bstp_list_mtx);
2156 	callout_drain(&bs->bs_bstpcallout);
2157 	BSTP_LOCK_DESTROY(bs);
2158 }
2159 
2160 void
2161 bstp_init(struct bstp_state *bs)
2162 {
2163 	BSTP_LOCK(bs);
2164 	callout_reset(&bs->bs_bstpcallout, hz, bstp_tick, bs);
2165 	bs->bs_running = 1;
2166 	bstp_reinit(bs);
2167 	BSTP_UNLOCK(bs);
2168 }
2169 
2170 void
2171 bstp_stop(struct bstp_state *bs)
2172 {
2173 	struct bstp_port *bp;
2174 
2175 	BSTP_LOCK(bs);
2176 
2177 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
2178 		bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
2179 
2180 	bs->bs_running = 0;
2181 	callout_stop(&bs->bs_bstpcallout);
2182 	BSTP_UNLOCK(bs);
2183 }
2184 
2185 int
2186 bstp_create(struct bstp_state *bs, struct bstp_port *bp, struct ifnet *ifp)
2187 {
2188 	bzero(bp, sizeof(struct bstp_port));
2189 
2190 	BSTP_LOCK(bs);
2191 	bp->bp_ifp = ifp;
2192 	bp->bp_bs = bs;
2193 	bp->bp_priority = BSTP_DEFAULT_PORT_PRIORITY;
2194 	TASK_INIT(&bp->bp_statetask, 0, bstp_notify_state, bp);
2195 	TASK_INIT(&bp->bp_rtagetask, 0, bstp_notify_rtage, bp);
2196 
2197 	/* Init state */
2198 	bp->bp_infois = BSTP_INFO_DISABLED;
2199 	bp->bp_flags = BSTP_PORT_AUTOEDGE|BSTP_PORT_AUTOPTP;
2200 	bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
2201 	bstp_set_port_proto(bp, bs->bs_protover);
2202 	bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2203 	bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
2204 	bp->bp_path_cost = bstp_calc_path_cost(bp);
2205 	BSTP_UNLOCK(bs);
2206 	return (0);
2207 }
2208 
2209 int
2210 bstp_enable(struct bstp_port *bp)
2211 {
2212 	struct bstp_state *bs = bp->bp_bs;
2213 	struct ifnet *ifp = bp->bp_ifp;
2214 
2215 	KASSERT(bp->bp_active == 0, ("already a bstp member"));
2216 
2217 	switch (ifp->if_type) {
2218 		case IFT_ETHER:	/* These can do spanning tree. */
2219 			break;
2220 		default:
2221 			/* Nothing else can. */
2222 			return (EINVAL);
2223 	}
2224 
2225 	BSTP_LOCK(bs);
2226 	LIST_INSERT_HEAD(&bs->bs_bplist, bp, bp_next);
2227 	bp->bp_active = 1;
2228 	bp->bp_flags |= BSTP_PORT_NEWINFO;
2229 	bstp_reinit(bs);
2230 	bstp_update_roles(bs, bp);
2231 	BSTP_UNLOCK(bs);
2232 	return (0);
2233 }
2234 
2235 void
2236 bstp_disable(struct bstp_port *bp)
2237 {
2238 	struct bstp_state *bs = bp->bp_bs;
2239 
2240 	KASSERT(bp->bp_active == 1, ("not a bstp member"));
2241 
2242 	BSTP_LOCK(bs);
2243 	bstp_disable_port(bs, bp);
2244 	LIST_REMOVE(bp, bp_next);
2245 	bp->bp_active = 0;
2246 	bstp_reinit(bs);
2247 	BSTP_UNLOCK(bs);
2248 }
2249 
2250 /*
2251  * The bstp_port structure is about to be freed by the parent bridge.
2252  */
2253 void
2254 bstp_destroy(struct bstp_port *bp)
2255 {
2256 	KASSERT(bp->bp_active == 0, ("port is still attached"));
2257 	taskqueue_drain(taskqueue_swi, &bp->bp_statetask);
2258 	taskqueue_drain(taskqueue_swi, &bp->bp_rtagetask);
2259 }
2260