xref: /openbsd/sys/net/bridgestp.c (revision 274d7c50)
1 /*	$OpenBSD: bridgestp.c,v 1.73 2019/11/07 07:36:31 dlg 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 
30 /*
31  * Implementation of the spanning tree protocol as defined in
32  * ISO/IEC 802.1D-2004, June 9, 2004.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/mbuf.h>
38 #include <sys/socket.h>
39 #include <sys/ioctl.h>
40 #include <sys/device.h>
41 #include <sys/kernel.h>
42 #include <sys/timeout.h>
43 
44 #include <net/if.h>
45 #include <net/if_types.h>
46 #include <net/if_dl.h>
47 #include <net/if_llc.h>
48 #include <net/netisr.h>
49 
50 #include <netinet/in.h>
51 #include <netinet/ip.h>
52 #include <netinet/if_ether.h>
53 
54 #include <net/if_bridge.h>
55 
56 /* STP port states */
57 #define	BSTP_IFSTATE_DISABLED	0
58 #define	BSTP_IFSTATE_LISTENING	1
59 #define	BSTP_IFSTATE_LEARNING	2
60 #define	BSTP_IFSTATE_FORWARDING	3
61 #define	BSTP_IFSTATE_BLOCKING	4
62 #define	BSTP_IFSTATE_DISCARDING	5
63 
64 #define	BSTP_TCSTATE_ACTIVE	1
65 #define	BSTP_TCSTATE_DETECTED	2
66 #define	BSTP_TCSTATE_INACTIVE	3
67 #define	BSTP_TCSTATE_LEARNING	4
68 #define	BSTP_TCSTATE_PROPAG	5
69 #define	BSTP_TCSTATE_ACK	6
70 #define	BSTP_TCSTATE_TC		7
71 #define	BSTP_TCSTATE_TCN	8
72 
73 #define	BSTP_ROLE_DISABLED	0
74 #define	BSTP_ROLE_ROOT		1
75 #define	BSTP_ROLE_DESIGNATED	2
76 #define	BSTP_ROLE_ALTERNATE	3
77 #define	BSTP_ROLE_BACKUP	4
78 
79 /* STP port flags */
80 #define	BSTP_PORT_CANMIGRATE	0x0001
81 #define	BSTP_PORT_NEWINFO	0x0002
82 #define	BSTP_PORT_DISPUTED	0x0004
83 #define	BSTP_PORT_ADMCOST	0x0008
84 #define	BSTP_PORT_AUTOEDGE	0x0010
85 
86 /* BPDU priority */
87 #define	BSTP_PDU_SUPERIOR	1
88 #define	BSTP_PDU_REPEATED	2
89 #define	BSTP_PDU_INFERIOR	3
90 #define	BSTP_PDU_INFERIORALT	4
91 #define	BSTP_PDU_OTHER		5
92 
93 /* BPDU flags */
94 #define	BSTP_PDU_PRMASK		0x0c		/* Port Role */
95 #define	BSTP_PDU_PRSHIFT	2		/* Port Role offset */
96 #define	BSTP_PDU_F_UNKN		0x00		/* Unknown port    (00) */
97 #define	BSTP_PDU_F_ALT		0x01		/* Alt/Backup port (01) */
98 #define	BSTP_PDU_F_ROOT		0x02		/* Root port       (10) */
99 #define	BSTP_PDU_F_DESG		0x03		/* Designated port (11) */
100 
101 #define	BSTP_PDU_STPMASK	0x81		/* strip unused STP flags */
102 #define	BSTP_PDU_RSTPMASK	0x7f		/* strip unused RSTP flags */
103 #define	BSTP_PDU_F_TC		0x01		/* Topology change */
104 #define	BSTP_PDU_F_P		0x02		/* Proposal flag */
105 #define	BSTP_PDU_F_L		0x10		/* Learning flag */
106 #define	BSTP_PDU_F_F		0x20		/* Forwarding flag */
107 #define	BSTP_PDU_F_A		0x40		/* Agreement flag */
108 #define	BSTP_PDU_F_TCA		0x80		/* Topology change ack */
109 
110 /*
111  * Spanning tree defaults.
112  */
113 #define	BSTP_DEFAULT_MAX_AGE		(20 * 256)
114 #define	BSTP_DEFAULT_HELLO_TIME		(2 * 256)
115 #define	BSTP_DEFAULT_FORWARD_DELAY	(15 * 256)
116 #define	BSTP_DEFAULT_HOLD_TIME		(1 * 256)
117 #define	BSTP_DEFAULT_MIGRATE_DELAY	(3 * 256)
118 #define	BSTP_DEFAULT_HOLD_COUNT		6
119 #define	BSTP_DEFAULT_BRIDGE_PRIORITY	0x8000
120 #define	BSTP_DEFAULT_PORT_PRIORITY	0x80
121 #define	BSTP_DEFAULT_PATH_COST		55
122 #define	BSTP_MIN_HELLO_TIME		(1 * 256)
123 #define	BSTP_MIN_MAX_AGE		(6 * 256)
124 #define	BSTP_MIN_FORWARD_DELAY		(4 * 256)
125 #define	BSTP_MIN_HOLD_COUNT		1
126 #define	BSTP_MAX_HELLO_TIME		(2 * 256)
127 #define	BSTP_MAX_MAX_AGE		(40 * 256)
128 #define	BSTP_MAX_FORWARD_DELAY		(30 * 256)
129 #define	BSTP_MAX_HOLD_COUNT		10
130 #define	BSTP_MAX_PRIORITY		61440
131 #define	BSTP_MAX_PORT_PRIORITY		240
132 #define	BSTP_MAX_PATH_COST		200000000
133 
134 /* BPDU message types */
135 #define	BSTP_MSGTYPE_CFG	0x00		/* Configuration */
136 #define	BSTP_MSGTYPE_RSTP	0x02		/* Rapid STP */
137 #define	BSTP_MSGTYPE_TCN	0x80		/* Topology chg notification */
138 
139 #define	BSTP_INFO_RECEIVED	1
140 #define	BSTP_INFO_MINE		2
141 #define	BSTP_INFO_AGED		3
142 #define	BSTP_INFO_DISABLED	4
143 
144 #define	BSTP_MESSAGE_AGE_INCR	(1 * 256)	/* in 256ths of a second */
145 #define	BSTP_TICK_VAL		(1 * 256)	/* in 256ths of a second */
146 #define	BSTP_LINK_TIMER		(BSTP_TICK_VAL * 15)
147 
148 #ifdef	BRIDGESTP_DEBUG
149 #define	DPRINTF(fmt, arg...)	printf("bstp: " fmt, ##arg)
150 #else
151 #define	DPRINTF(fmt, arg...)
152 #endif
153 
154 #define	PV2ADDR(pv, eaddr)	do {		\
155 	eaddr[0] = pv >> 40;			\
156 	eaddr[1] = pv >> 32;			\
157 	eaddr[2] = pv >> 24;			\
158 	eaddr[3] = pv >> 16;			\
159 	eaddr[4] = pv >> 8;			\
160 	eaddr[5] = pv >> 0;			\
161 } while (0)
162 
163 #define	INFO_BETTER	1
164 #define	INFO_SAME	0
165 #define	INFO_WORSE	-1
166 
167 #define	BSTP_IFQ_PRIO	6
168 
169 /*
170  * Because BPDU's do not make nicely aligned structures, two different
171  * declarations are used: bstp_?bpdu (wire representation, packed) and
172  * bstp_*_unit (internal, nicely aligned version).
173  */
174 
175 /* configuration bridge protocol data unit */
176 struct bstp_cbpdu {
177 	u_int8_t	cbu_dsap;		/* LLC: destination sap */
178 	u_int8_t	cbu_ssap;		/* LLC: source sap */
179 	u_int8_t	cbu_ctl;		/* LLC: control */
180 	u_int16_t	cbu_protoid;		/* protocol id */
181 	u_int8_t	cbu_protover;		/* protocol version */
182 	u_int8_t	cbu_bpdutype;		/* message type */
183 	u_int8_t	cbu_flags;		/* flags (below) */
184 
185 	/* root id */
186 	u_int16_t	cbu_rootpri;		/* root priority */
187 	u_int8_t	cbu_rootaddr[6];	/* root address */
188 
189 	u_int32_t	cbu_rootpathcost;	/* root path cost */
190 
191 	/* bridge id */
192 	u_int16_t	cbu_bridgepri;		/* bridge priority */
193 	u_int8_t	cbu_bridgeaddr[6];	/* bridge address */
194 
195 	u_int16_t	cbu_portid;		/* port id */
196 	u_int16_t	cbu_messageage;		/* current message age */
197 	u_int16_t	cbu_maxage;		/* maximum age */
198 	u_int16_t	cbu_hellotime;		/* hello time */
199 	u_int16_t	cbu_forwarddelay;	/* forwarding delay */
200 	u_int8_t	cbu_versionlen;		/* version 1 length */
201 } __packed;
202 
203 #define	BSTP_BPDU_STP_LEN	(3 + 35)	/* LLC + STP pdu */
204 #define	BSTP_BPDU_RSTP_LEN	(3 + 36)	/* LLC + RSTP pdu */
205 
206 /* topology change notification bridge protocol data unit */
207 struct bstp_tbpdu {
208 	u_int8_t	tbu_dsap;		/* LLC: destination sap */
209 	u_int8_t	tbu_ssap;		/* LLC: source sap */
210 	u_int8_t	tbu_ctl;		/* LLC: control */
211 	u_int16_t	tbu_protoid;		/* protocol id */
212 	u_int8_t	tbu_protover;		/* protocol version */
213 	u_int8_t	tbu_bpdutype;		/* message type */
214 } __packed;
215 
216 const u_int8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
217 
218 
219 void	bstp_transmit(struct bstp_state *, struct bstp_port *);
220 void	bstp_transmit_bpdu(struct bstp_state *, struct bstp_port *);
221 void	bstp_transmit_tcn(struct bstp_state *, struct bstp_port *);
222 void	bstp_decode_bpdu(struct bstp_port *, struct bstp_cbpdu *,
223 	    struct bstp_config_unit *);
224 void	bstp_send_bpdu(struct bstp_state *, struct bstp_port *,
225 	    struct bstp_cbpdu *);
226 int	bstp_pdu_flags(struct bstp_port *);
227 void	bstp_received_stp(struct bstp_state *, struct bstp_port *,
228 	    struct mbuf **, struct bstp_tbpdu *);
229 void	bstp_received_rstp(struct bstp_state *, struct bstp_port *,
230 	    struct mbuf **, struct bstp_tbpdu *);
231 void	bstp_received_tcn(struct bstp_state *, struct bstp_port *,
232 	    struct bstp_tcn_unit *);
233 void	bstp_received_bpdu(struct bstp_state *, struct bstp_port *,
234 	    struct bstp_config_unit *);
235 int	bstp_pdu_rcvtype(struct bstp_port *, struct bstp_config_unit *);
236 int	bstp_pdu_bettersame(struct bstp_port *, int);
237 int	bstp_info_cmp(struct bstp_pri_vector *,
238 	    struct bstp_pri_vector *);
239 int	bstp_info_superior(struct bstp_pri_vector *,
240 	    struct bstp_pri_vector *);
241 void	bstp_assign_roles(struct bstp_state *);
242 void	bstp_update_roles(struct bstp_state *, struct bstp_port *);
243 void	bstp_update_state(struct bstp_state *, struct bstp_port *);
244 void	bstp_update_tc(struct bstp_port *);
245 void	bstp_update_info(struct bstp_port *);
246 void	bstp_set_other_tcprop(struct bstp_port *);
247 void	bstp_set_all_reroot(struct bstp_state *);
248 void	bstp_set_all_sync(struct bstp_state *);
249 void	bstp_set_port_state(struct bstp_port *, int);
250 void	bstp_set_port_role(struct bstp_port *, int);
251 void	bstp_set_port_proto(struct bstp_port *, int);
252 void	bstp_set_port_tc(struct bstp_port *, int);
253 void	bstp_set_timer_tc(struct bstp_port *);
254 void	bstp_set_timer_msgage(struct bstp_port *);
255 void	bstp_reset(struct bstp_state *);
256 int	bstp_rerooted(struct bstp_state *, struct bstp_port *);
257 u_int32_t	bstp_calc_path_cost(struct bstp_port *);
258 void	bstp_notify_rtage(struct bstp_port *, int);
259 void	bstp_ifupdstatus(struct bstp_state *, struct bstp_port *);
260 void	bstp_enable_port(struct bstp_state *, struct bstp_port *);
261 void	bstp_disable_port(struct bstp_state *, struct bstp_port *);
262 void	bstp_tick(void *);
263 void	bstp_timer_start(struct bstp_timer *, u_int16_t);
264 void	bstp_timer_stop(struct bstp_timer *);
265 void	bstp_timer_latch(struct bstp_timer *);
266 int	bstp_timer_expired(struct bstp_timer *);
267 void	bstp_hello_timer_expiry(struct bstp_state *,
268 		    struct bstp_port *);
269 void	bstp_message_age_expiry(struct bstp_state *,
270 		    struct bstp_port *);
271 void	bstp_migrate_delay_expiry(struct bstp_state *,
272 		    struct bstp_port *);
273 void	bstp_edge_delay_expiry(struct bstp_state *,
274 		    struct bstp_port *);
275 int	bstp_addr_cmp(const u_int8_t *, const u_int8_t *);
276 int	bstp_same_bridgeid(u_int64_t, u_int64_t);
277 
278 
279 void
280 bstp_transmit(struct bstp_state *bs, struct bstp_port *bp)
281 {
282 	if ((bs->bs_ifflags & IFF_RUNNING) == 0 || bp == NULL)
283 		return;
284 
285 	/*
286 	 * a PDU can only be sent if we have tx quota left and the
287 	 * hello timer is running.
288 	 */
289 	if (bp->bp_hello_timer.active == 0) {
290 		/* Test if it needs to be reset */
291 		bstp_hello_timer_expiry(bs, bp);
292 		return;
293 	}
294 	if (bp->bp_txcount > bs->bs_txholdcount)
295 		/* Ran out of karma */
296 		return;
297 
298 	if (bp->bp_protover == BSTP_PROTO_RSTP) {
299 		bstp_transmit_bpdu(bs, bp);
300 		bp->bp_tc_ack = 0;
301 	} else { /* STP */
302 		switch (bp->bp_role) {
303 		case BSTP_ROLE_DESIGNATED:
304 			bstp_transmit_bpdu(bs, bp);
305 			bp->bp_tc_ack = 0;
306 			break;
307 
308 		case BSTP_ROLE_ROOT:
309 			bstp_transmit_tcn(bs, bp);
310 			break;
311 		}
312 	}
313 	bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
314 	bp->bp_flags &= ~BSTP_PORT_NEWINFO;
315 }
316 
317 void
318 bstp_transmit_bpdu(struct bstp_state *bs, struct bstp_port *bp)
319 {
320 	struct bstp_cbpdu bpdu;
321 
322 	bpdu.cbu_rootpri = htons(bp->bp_desg_pv.pv_root_id >> 48);
323 	PV2ADDR(bp->bp_desg_pv.pv_root_id, bpdu.cbu_rootaddr);
324 
325 	bpdu.cbu_rootpathcost = htonl(bp->bp_desg_pv.pv_cost);
326 
327 	bpdu.cbu_bridgepri = htons(bp->bp_desg_pv.pv_dbridge_id >> 48);
328 	PV2ADDR(bp->bp_desg_pv.pv_dbridge_id, bpdu.cbu_bridgeaddr);
329 
330 	bpdu.cbu_portid = htons(bp->bp_port_id);
331 	bpdu.cbu_messageage = htons(bp->bp_desg_msg_age);
332 	bpdu.cbu_maxage = htons(bp->bp_desg_max_age);
333 	bpdu.cbu_hellotime = htons(bp->bp_desg_htime);
334 	bpdu.cbu_forwarddelay = htons(bp->bp_desg_fdelay);
335 
336 	bpdu.cbu_flags = bstp_pdu_flags(bp);
337 
338 	switch (bp->bp_protover) {
339 	case BSTP_PROTO_STP:
340 		bpdu.cbu_bpdutype = BSTP_MSGTYPE_CFG;
341 		break;
342 	case BSTP_PROTO_RSTP:
343 		bpdu.cbu_bpdutype = BSTP_MSGTYPE_RSTP;
344 		break;
345 	}
346 
347 	bstp_send_bpdu(bs, bp, &bpdu);
348 }
349 
350 void
351 bstp_transmit_tcn(struct bstp_state *bs, struct bstp_port *bp)
352 {
353 	struct bstp_tbpdu bpdu;
354 	struct ifnet *ifp = bp->bp_ifp;
355 	struct ether_header *eh;
356 	struct mbuf *m;
357 
358 	if (ifp == NULL || (ifp->if_flags & IFF_RUNNING) == 0)
359 		return;
360 
361 	MGETHDR(m, M_DONTWAIT, MT_DATA);
362 	if (m == NULL)
363 		return;
364 	m->m_pkthdr.ph_ifidx = ifp->if_index;
365 	m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
366 	m->m_pkthdr.pf.prio = BSTP_IFQ_PRIO;
367 	m->m_len = m->m_pkthdr.len;
368 
369 	eh = mtod(m, struct ether_header *);
370 	bcopy(LLADDR(ifp->if_sadl), eh->ether_shost, ETHER_ADDR_LEN);
371 	bcopy(bstp_etheraddr, eh->ether_dhost, ETHER_ADDR_LEN);
372 	eh->ether_type = htons(sizeof(bpdu));
373 
374 	bpdu.tbu_ssap = bpdu.tbu_dsap = LLC_8021D_LSAP;
375 	bpdu.tbu_ctl = LLC_UI;
376 	bpdu.tbu_protoid = 0;
377 	bpdu.tbu_protover = 0;
378 	bpdu.tbu_bpdutype = BSTP_MSGTYPE_TCN;
379 	bcopy(&bpdu, mtod(m, caddr_t) + sizeof(*eh), sizeof(bpdu));
380 
381 	bp->bp_txcount++;
382 	if_enqueue(ifp, m);
383 }
384 
385 void
386 bstp_decode_bpdu(struct bstp_port *bp, struct bstp_cbpdu *cpdu,
387     struct bstp_config_unit *cu)
388 {
389 	int flags;
390 
391 	cu->cu_pv.pv_root_id =
392 	    (((u_int64_t)ntohs(cpdu->cbu_rootpri)) << 48) |
393 	    (((u_int64_t)cpdu->cbu_rootaddr[0]) << 40) |
394 	    (((u_int64_t)cpdu->cbu_rootaddr[1]) << 32) |
395 	    (((u_int64_t)cpdu->cbu_rootaddr[2]) << 24) |
396 	    (((u_int64_t)cpdu->cbu_rootaddr[3]) << 16) |
397 	    (((u_int64_t)cpdu->cbu_rootaddr[4]) << 8) |
398 	    (((u_int64_t)cpdu->cbu_rootaddr[5]) << 0);
399 
400 	cu->cu_pv.pv_dbridge_id =
401 	    (((u_int64_t)ntohs(cpdu->cbu_bridgepri)) << 48) |
402 	    (((u_int64_t)cpdu->cbu_bridgeaddr[0]) << 40) |
403 	    (((u_int64_t)cpdu->cbu_bridgeaddr[1]) << 32) |
404 	    (((u_int64_t)cpdu->cbu_bridgeaddr[2]) << 24) |
405 	    (((u_int64_t)cpdu->cbu_bridgeaddr[3]) << 16) |
406 	    (((u_int64_t)cpdu->cbu_bridgeaddr[4]) << 8) |
407 	    (((u_int64_t)cpdu->cbu_bridgeaddr[5]) << 0);
408 
409 	cu->cu_pv.pv_cost = ntohl(cpdu->cbu_rootpathcost);
410 	cu->cu_message_age = ntohs(cpdu->cbu_messageage);
411 	cu->cu_max_age = ntohs(cpdu->cbu_maxage);
412 	cu->cu_hello_time = ntohs(cpdu->cbu_hellotime);
413 	cu->cu_forward_delay = ntohs(cpdu->cbu_forwarddelay);
414 	cu->cu_pv.pv_dport_id = ntohs(cpdu->cbu_portid);
415 	cu->cu_pv.pv_port_id = bp->bp_port_id;
416 	cu->cu_message_type = cpdu->cbu_bpdutype;
417 
418 	/* Strip off unused flags in STP mode */
419 	flags = cpdu->cbu_flags;
420 	switch (cpdu->cbu_protover) {
421 	case BSTP_PROTO_STP:
422 		flags &= BSTP_PDU_STPMASK;
423 		/* A STP BPDU explicitly conveys a Designated Port */
424 		cu->cu_role = BSTP_ROLE_DESIGNATED;
425 		break;
426 	case BSTP_PROTO_RSTP:
427 		flags &= BSTP_PDU_RSTPMASK;
428 		break;
429 	}
430 
431 	cu->cu_topology_change_ack =
432 		(flags & BSTP_PDU_F_TCA) ? 1 : 0;
433 	cu->cu_proposal =
434 		(flags & BSTP_PDU_F_P) ? 1 : 0;
435 	cu->cu_agree =
436 		(flags & BSTP_PDU_F_A) ? 1 : 0;
437 	cu->cu_learning =
438 		(flags & BSTP_PDU_F_L) ? 1 : 0;
439 	cu->cu_forwarding =
440 		(flags & BSTP_PDU_F_F) ? 1 : 0;
441 	cu->cu_topology_change =
442 		(flags & BSTP_PDU_F_TC) ? 1 : 0;
443 
444 	switch ((flags & BSTP_PDU_PRMASK) >> BSTP_PDU_PRSHIFT) {
445 	case BSTP_PDU_F_ROOT:
446 		cu->cu_role = BSTP_ROLE_ROOT;
447 		break;
448 	case BSTP_PDU_F_ALT:
449 		cu->cu_role = BSTP_ROLE_ALTERNATE;
450 		break;
451 	case BSTP_PDU_F_DESG:
452 		cu->cu_role = BSTP_ROLE_DESIGNATED;
453 		break;
454 	}
455 }
456 
457 void
458 bstp_send_bpdu(struct bstp_state *bs, struct bstp_port *bp,
459     struct bstp_cbpdu *bpdu)
460 {
461 	struct ifnet *ifp = bp->bp_ifp;
462 	struct mbuf *m;
463 	struct ether_header *eh;
464 	int s;
465 
466 	s = splnet();
467 	if (ifp == NULL || (ifp->if_flags & IFF_RUNNING) == 0)
468 		goto done;
469 
470 	MGETHDR(m, M_DONTWAIT, MT_DATA);
471 	if (m == NULL)
472 		goto done;
473 
474 	eh = mtod(m, struct ether_header *);
475 
476 	bpdu->cbu_ssap = bpdu->cbu_dsap = LLC_8021D_LSAP;
477 	bpdu->cbu_ctl = LLC_UI;
478 	bpdu->cbu_protoid = htons(BSTP_PROTO_ID);
479 
480 	memcpy(eh->ether_shost, LLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
481 	memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
482 
483 	switch (bpdu->cbu_bpdutype) {
484 	case BSTP_MSGTYPE_CFG:
485 		bpdu->cbu_protover = BSTP_PROTO_STP;
486 		m->m_pkthdr.len = sizeof(*eh) + BSTP_BPDU_STP_LEN;
487 		eh->ether_type = htons(BSTP_BPDU_STP_LEN);
488 		memcpy(mtod(m, caddr_t) + sizeof(*eh), bpdu,
489 		    BSTP_BPDU_STP_LEN);
490 		break;
491 	case BSTP_MSGTYPE_RSTP:
492 		bpdu->cbu_protover = BSTP_PROTO_RSTP;
493 		bpdu->cbu_versionlen = htons(0);
494 		m->m_pkthdr.len = sizeof(*eh) + BSTP_BPDU_RSTP_LEN;
495 		eh->ether_type = htons(BSTP_BPDU_RSTP_LEN);
496 		memcpy(mtod(m, caddr_t) + sizeof(*eh), bpdu,
497 		    BSTP_BPDU_RSTP_LEN);
498 		break;
499 	default:
500 		panic("not implemented");
501 	}
502 	m->m_pkthdr.ph_ifidx = ifp->if_index;
503 	m->m_len = m->m_pkthdr.len;
504 	m->m_pkthdr.pf.prio = BSTP_IFQ_PRIO;
505 
506 	bp->bp_txcount++;
507 	if_enqueue(ifp, m);
508  done:
509 	splx(s);
510 }
511 
512 int
513 bstp_pdu_flags(struct bstp_port *bp)
514 {
515 	int flags = 0;
516 
517 	if (bp->bp_proposing && bp->bp_state != BSTP_IFSTATE_FORWARDING)
518 		flags |= BSTP_PDU_F_P;
519 
520 	if (bp->bp_agree)
521 		flags |= BSTP_PDU_F_A;
522 
523 	if (bp->bp_tc_timer.active)
524 		flags |= BSTP_PDU_F_TC;
525 
526 	if (bp->bp_tc_ack)
527 		flags |= BSTP_PDU_F_TCA;
528 
529 	switch (bp->bp_state) {
530 	case BSTP_IFSTATE_LEARNING:
531 		flags |= BSTP_PDU_F_L;
532 		break;
533 	case BSTP_IFSTATE_FORWARDING:
534 		flags |= (BSTP_PDU_F_L | BSTP_PDU_F_F);
535 		break;
536 	}
537 
538 	switch (bp->bp_role) {
539 	case BSTP_ROLE_ROOT:
540 		flags |= (BSTP_PDU_F_ROOT << BSTP_PDU_PRSHIFT);
541 		break;
542 	case BSTP_ROLE_ALTERNATE:
543 	case BSTP_ROLE_BACKUP:
544 		flags |= (BSTP_PDU_F_ALT << BSTP_PDU_PRSHIFT);
545 		break;
546 	case BSTP_ROLE_DESIGNATED:
547 		flags |= (BSTP_PDU_F_DESG << BSTP_PDU_PRSHIFT);
548 		break;
549 	}
550 
551 	/* Strip off unused flags in either mode */
552 	switch (bp->bp_protover) {
553 	case BSTP_PROTO_STP:
554 		flags &= BSTP_PDU_STPMASK;
555 		break;
556 	case BSTP_PROTO_RSTP:
557 		flags &= BSTP_PDU_RSTPMASK;
558 		break;
559 	}
560 	return (flags);
561 }
562 
563 struct mbuf *
564 bstp_input(struct bstp_state *bs, struct bstp_port *bp,
565     struct ether_header *eh, struct mbuf *m)
566 {
567 	struct bstp_tbpdu tpdu;
568 	u_int16_t len;
569 
570 	if (bs == NULL || bp == NULL || bp->bp_active == 0)
571 		return (m);
572 
573 	len = ntohs(eh->ether_type);
574 	if (len < sizeof(tpdu))
575 		goto out;
576 
577 	m_adj(m, ETHER_HDR_LEN);
578 
579 	if (m->m_pkthdr.len > len)
580 		m_adj(m, len - m->m_pkthdr.len);
581 	if ((m = m_pullup(m, sizeof(tpdu))) == NULL)
582 		goto out;
583 	bcopy(mtod(m, struct tpdu *), &tpdu, sizeof(tpdu));
584 
585 	if (tpdu.tbu_dsap != LLC_8021D_LSAP ||
586 	    tpdu.tbu_ssap != LLC_8021D_LSAP ||
587 	    tpdu.tbu_ctl != LLC_UI)
588 		goto out;
589 	if (tpdu.tbu_protoid != BSTP_PROTO_ID)
590 		goto out;
591 
592 	/*
593 	 * We can treat later versions of the PDU as the same as the maximum
594 	 * version we implement. All additional parameters/flags are ignored.
595 	 */
596 	if (tpdu.tbu_protover > BSTP_PROTO_MAX)
597 		tpdu.tbu_protover = BSTP_PROTO_MAX;
598 
599 	if (tpdu.tbu_protover != bp->bp_protover) {
600 		/*
601 		 * Wait for the migration delay timer to expire before changing
602 		 * protocol version to avoid flip-flops.
603 		 */
604 		if (bp->bp_flags & BSTP_PORT_CANMIGRATE)
605 			bstp_set_port_proto(bp, tpdu.tbu_protover);
606 		else
607 			goto out;
608 	}
609 
610 	/* Clear operedge upon receiving a PDU on the port */
611 	bp->bp_operedge = 0;
612 	bstp_timer_start(&bp->bp_edge_delay_timer,
613 	    BSTP_DEFAULT_MIGRATE_DELAY);
614 
615 	switch (tpdu.tbu_protover) {
616 	case BSTP_PROTO_STP:
617 		bstp_received_stp(bs, bp, &m, &tpdu);
618 		break;
619 	case BSTP_PROTO_RSTP:
620 		bstp_received_rstp(bs, bp, &m, &tpdu);
621 		break;
622 	}
623  out:
624 	m_freem(m);
625 	return (NULL);
626 }
627 
628 void
629 bstp_received_stp(struct bstp_state *bs, struct bstp_port *bp,
630     struct mbuf **mp, struct bstp_tbpdu *tpdu)
631 {
632 	struct bstp_cbpdu cpdu;
633 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
634 	struct bstp_tcn_unit tu;
635 
636 	switch (tpdu->tbu_bpdutype) {
637 	case BSTP_MSGTYPE_TCN:
638 		tu.tu_message_type = tpdu->tbu_bpdutype;
639 		bstp_received_tcn(bs, bp, &tu);
640 		break;
641 	case BSTP_MSGTYPE_CFG:
642 		if ((*mp)->m_len < BSTP_BPDU_STP_LEN &&
643 		    (*mp = m_pullup(*mp, BSTP_BPDU_STP_LEN)) == NULL)
644 			return;
645 		memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_STP_LEN);
646 
647 		bstp_decode_bpdu(bp, &cpdu, cu);
648 		bstp_received_bpdu(bs, bp, cu);
649 		break;
650 	}
651 }
652 
653 void
654 bstp_received_rstp(struct bstp_state *bs, struct bstp_port *bp,
655     struct mbuf **mp, struct bstp_tbpdu *tpdu)
656 {
657 	struct bstp_cbpdu cpdu;
658 	struct bstp_config_unit *cu = &bp->bp_msg_cu;
659 
660 	if (tpdu->tbu_bpdutype != BSTP_MSGTYPE_RSTP)
661 		return;
662 
663 	if ((*mp)->m_len < BSTP_BPDU_RSTP_LEN &&
664 	    (*mp = m_pullup(*mp, BSTP_BPDU_RSTP_LEN)) == NULL)
665 		return;
666 	memcpy(&cpdu, mtod(*mp, caddr_t), BSTP_BPDU_RSTP_LEN);
667 
668 	bstp_decode_bpdu(bp, &cpdu, cu);
669 	bstp_received_bpdu(bs, bp, cu);
670 }
671 
672 void
673 bstp_received_tcn(struct bstp_state *bs, struct bstp_port *bp,
674     struct bstp_tcn_unit *tcn)
675 {
676 	bp->bp_rcvdtcn = 1;
677 	bstp_update_tc(bp);
678 }
679 
680 void
681 bstp_received_bpdu(struct bstp_state *bs, struct bstp_port *bp,
682     struct bstp_config_unit *cu)
683 {
684 	int type;
685 
686 	/* We need to have transitioned to INFO_MINE before proceeding */
687 	switch (bp->bp_infois) {
688 	case BSTP_INFO_DISABLED:
689 	case BSTP_INFO_AGED:
690 		return;
691 	}
692 
693 	type = bstp_pdu_rcvtype(bp, cu);
694 
695 	switch (type) {
696 	case BSTP_PDU_SUPERIOR:
697 		bs->bs_allsynced = 0;
698 		bp->bp_agreed = 0;
699 		bp->bp_proposing = 0;
700 
701 		if (cu->cu_proposal && cu->cu_forwarding == 0)
702 			bp->bp_proposed = 1;
703 		if (cu->cu_topology_change)
704 			bp->bp_rcvdtc = 1;
705 		if (cu->cu_topology_change_ack)
706 			bp->bp_rcvdtca = 1;
707 
708 		if (bp->bp_agree &&
709 		    !bstp_pdu_bettersame(bp, BSTP_INFO_RECEIVED))
710 			bp->bp_agree = 0;
711 
712 		/* copy the received priority and timers to the port */
713 		bp->bp_port_pv = cu->cu_pv;
714 		bp->bp_port_msg_age = cu->cu_message_age;
715 		bp->bp_port_max_age = cu->cu_max_age;
716 		bp->bp_port_fdelay = cu->cu_forward_delay;
717 		bp->bp_port_htime =
718 		    (cu->cu_hello_time > BSTP_MIN_HELLO_TIME ?
719 		     cu->cu_hello_time : BSTP_MIN_HELLO_TIME);
720 
721 		/* set expiry for the new info */
722 		bstp_set_timer_msgage(bp);
723 
724 		bp->bp_infois = BSTP_INFO_RECEIVED;
725 		bstp_assign_roles(bs);
726 		break;
727 
728 	case BSTP_PDU_REPEATED:
729 		if (cu->cu_proposal && cu->cu_forwarding == 0)
730 			bp->bp_proposed = 1;
731 		if (cu->cu_topology_change)
732 			bp->bp_rcvdtc = 1;
733 		if (cu->cu_topology_change_ack)
734 			bp->bp_rcvdtca = 1;
735 
736 		/* rearm the age timer */
737 		bstp_set_timer_msgage(bp);
738 		break;
739 
740 	case BSTP_PDU_INFERIOR:
741 		if (cu->cu_learning) {
742 			bp->bp_agreed = 1;
743 			bp->bp_proposing = 0;
744 		}
745 		break;
746 
747 	case BSTP_PDU_INFERIORALT:
748 		/*
749 		 * only point to point links are allowed fast
750 		 * transitions to forwarding.
751 		 */
752 		if (cu->cu_agree && bp->bp_ptp_link) {
753 			bp->bp_agreed = 1;
754 			bp->bp_proposing = 0;
755 		} else
756 			bp->bp_agreed = 0;
757 
758 		if (cu->cu_topology_change)
759 			bp->bp_rcvdtc = 1;
760 		if (cu->cu_topology_change_ack)
761 			bp->bp_rcvdtca = 1;
762 		break;
763 
764 	case BSTP_PDU_OTHER:
765 		return;	/* do nothing */
766 	}
767 
768 	/* update the state machines with the new data */
769 	bstp_update_state(bs, bp);
770 }
771 
772 int
773 bstp_pdu_rcvtype(struct bstp_port *bp, struct bstp_config_unit *cu)
774 {
775 	int type;
776 
777 	/* default return type */
778 	type = BSTP_PDU_OTHER;
779 
780 	switch (cu->cu_role) {
781 	case BSTP_ROLE_DESIGNATED:
782 		if (bstp_info_superior(&bp->bp_port_pv, &cu->cu_pv))
783 			/* bpdu priority is superior */
784 			type = BSTP_PDU_SUPERIOR;
785 		else if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) ==
786 		    INFO_SAME) {
787 			if (bp->bp_port_msg_age != cu->cu_message_age ||
788 			    bp->bp_port_max_age != cu->cu_max_age ||
789 			    bp->bp_port_fdelay != cu->cu_forward_delay ||
790 			    bp->bp_port_htime != cu->cu_hello_time)
791 				/* bpdu priority is equal and timers differ */
792 				type = BSTP_PDU_SUPERIOR;
793 			else
794 				/* bpdu is equal */
795 				type = BSTP_PDU_REPEATED;
796 		} else
797 			/* bpdu priority is worse */
798 			type = BSTP_PDU_INFERIOR;
799 
800 		break;
801 
802 	case BSTP_ROLE_ROOT:
803 	case BSTP_ROLE_ALTERNATE:
804 	case BSTP_ROLE_BACKUP:
805 		if (bstp_info_cmp(&bp->bp_port_pv, &cu->cu_pv) <= INFO_SAME)
806 			/*
807 			 * not a designated port and priority is the same or
808 			 * worse
809 			 */
810 			type = BSTP_PDU_INFERIORALT;
811 		break;
812 	}
813 
814 	return (type);
815 }
816 
817 int
818 bstp_pdu_bettersame(struct bstp_port *bp, int newinfo)
819 {
820 	if (newinfo == BSTP_INFO_RECEIVED &&
821 	    bp->bp_infois == BSTP_INFO_RECEIVED &&
822 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_msg_cu.cu_pv) >= INFO_SAME)
823 		return (1);
824 
825 	if (newinfo == BSTP_INFO_MINE &&
826 	    bp->bp_infois == BSTP_INFO_MINE &&
827 	    bstp_info_cmp(&bp->bp_port_pv, &bp->bp_desg_pv) >= INFO_SAME)
828 		return (1);
829 
830 	return (0);
831 }
832 
833 int
834 bstp_info_cmp(struct bstp_pri_vector *pv,
835     struct bstp_pri_vector *cpv)
836 {
837 	if (cpv->pv_root_id < pv->pv_root_id)
838 		return (INFO_BETTER);
839 	if (cpv->pv_root_id > pv->pv_root_id)
840 		return (INFO_WORSE);
841 
842 	if (cpv->pv_cost < pv->pv_cost)
843 		return (INFO_BETTER);
844 	if (cpv->pv_cost > pv->pv_cost)
845 		return (INFO_WORSE);
846 
847 	if (cpv->pv_dbridge_id < pv->pv_dbridge_id)
848 		return (INFO_BETTER);
849 	if (cpv->pv_dbridge_id > pv->pv_dbridge_id)
850 		return (INFO_WORSE);
851 
852 	if (cpv->pv_dport_id < pv->pv_dport_id)
853 		return (INFO_BETTER);
854 	if (cpv->pv_dport_id > pv->pv_dport_id)
855 		return (INFO_WORSE);
856 
857 	return (INFO_SAME);
858 }
859 
860 /*
861  * This message priority vector is superior to the port priority vector and
862  * will replace it if, and only if, the message priority vector is better than
863  * the port priority vector, or the message has been transmitted from the same
864  * designated bridge and designated port as the port priority vector.
865  */
866 int
867 bstp_info_superior(struct bstp_pri_vector *pv,
868     struct bstp_pri_vector *cpv)
869 {
870 	if (bstp_info_cmp(pv, cpv) == INFO_BETTER ||
871 	    (bstp_same_bridgeid(pv->pv_dbridge_id, cpv->pv_dbridge_id) &&
872 	    (cpv->pv_dport_id & 0xfff) == (pv->pv_dport_id & 0xfff)))
873 		return (1);
874 	return (0);
875 }
876 
877 void
878 bstp_reset(struct bstp_state *bs)
879 {
880 	/* default to our priority vector */
881 	bs->bs_root_pv = bs->bs_bridge_pv;
882 	bs->bs_root_msg_age = 0;
883 	bs->bs_root_max_age = bs->bs_bridge_max_age;
884 	bs->bs_root_fdelay = bs->bs_bridge_fdelay;
885 	bs->bs_root_htime = bs->bs_bridge_htime;
886 	bs->bs_root_port = NULL;
887 }
888 
889 void
890 bstp_assign_roles(struct bstp_state *bs)
891 {
892 	struct bstp_port *bp, *rbp = NULL;
893 	struct bstp_pri_vector pv;
894 
895 	bstp_reset(bs);
896 
897 	/* check if any received info supersedes us */
898 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
899 		if (bp->bp_infois != BSTP_INFO_RECEIVED)
900 			continue;
901 
902 		pv = bp->bp_port_pv;
903 		pv.pv_cost += bp->bp_path_cost;
904 
905 		/*
906 		 * The root priority vector is the best of the set comprising
907 		 * the bridge priority vector plus all root path priority
908 		 * vectors whose bridge address is not equal to us.
909 		 */
910 		if (bstp_same_bridgeid(pv.pv_dbridge_id,
911 		    bs->bs_bridge_pv.pv_dbridge_id) == 0 &&
912 		    bstp_info_cmp(&bs->bs_root_pv, &pv) == INFO_BETTER) {
913 			/* the port vector replaces the root */
914 			bs->bs_root_pv = pv;
915 			bs->bs_root_msg_age = bp->bp_port_msg_age +
916 			    BSTP_MESSAGE_AGE_INCR;
917 			bs->bs_root_max_age = bp->bp_port_max_age;
918 			bs->bs_root_fdelay = bp->bp_port_fdelay;
919 			bs->bs_root_htime = bp->bp_port_htime;
920 			rbp = bp;
921 		}
922 	}
923 
924 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
925 		/* calculate the port designated vector */
926 		bp->bp_desg_pv.pv_root_id = bs->bs_root_pv.pv_root_id;
927 		bp->bp_desg_pv.pv_cost = bs->bs_root_pv.pv_cost;
928 		bp->bp_desg_pv.pv_dbridge_id = bs->bs_bridge_pv.pv_dbridge_id;
929 		bp->bp_desg_pv.pv_dport_id = bp->bp_port_id;
930 		bp->bp_desg_pv.pv_port_id = bp->bp_port_id;
931 
932 		/* calculate designated times */
933 		bp->bp_desg_msg_age = bs->bs_root_msg_age;
934 		bp->bp_desg_max_age = bs->bs_root_max_age;
935 		bp->bp_desg_fdelay = bs->bs_root_fdelay;
936 		bp->bp_desg_htime = bs->bs_bridge_htime;
937 
938 
939 		switch (bp->bp_infois) {
940 		case BSTP_INFO_DISABLED:
941 			bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
942 			break;
943 
944 		case BSTP_INFO_AGED:
945 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
946 			bstp_update_info(bp);
947 			break;
948 
949 		case BSTP_INFO_MINE:
950 			bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
951 			/* update the port info if stale */
952 			if (bstp_info_cmp(&bp->bp_port_pv,
953 			    &bp->bp_desg_pv) != INFO_SAME ||
954 			    (rbp != NULL &&
955 			    (bp->bp_port_msg_age != rbp->bp_port_msg_age ||
956 			    bp->bp_port_max_age != rbp->bp_port_max_age ||
957 			    bp->bp_port_fdelay != rbp->bp_port_fdelay ||
958 			    bp->bp_port_htime != rbp->bp_port_htime)))
959 				bstp_update_info(bp);
960 			break;
961 
962 		case BSTP_INFO_RECEIVED:
963 			if (bp == rbp) {
964 				/*
965 				 * root priority is derived from this
966 				 * port, make it the root port.
967 				 */
968 				bstp_set_port_role(bp, BSTP_ROLE_ROOT);
969 				bs->bs_root_port = bp;
970 			} else if (bstp_info_cmp(&bp->bp_port_pv,
971 				    &bp->bp_desg_pv) == INFO_BETTER) {
972 				/*
973 				 * the port priority is lower than the root
974 				 * port.
975 				 */
976 				bstp_set_port_role(bp, BSTP_ROLE_DESIGNATED);
977 				bstp_update_info(bp);
978 			} else {
979 				if (bstp_same_bridgeid(
980 				    bp->bp_port_pv.pv_dbridge_id,
981 				    bs->bs_bridge_pv.pv_dbridge_id)) {
982 					/*
983 					 * the designated bridge refers to
984 					 * another port on this bridge.
985 					 */
986 					bstp_set_port_role(bp,
987 					    BSTP_ROLE_BACKUP);
988 				} else {
989 					/*
990 					 * the port is an inferior path to the
991 					 * root bridge.
992 					 */
993 					bstp_set_port_role(bp,
994 					    BSTP_ROLE_ALTERNATE);
995 				}
996 			}
997 			break;
998 		}
999 	}
1000 }
1001 
1002 void
1003 bstp_update_state(struct bstp_state *bs, struct bstp_port *bp)
1004 {
1005 	struct bstp_port *bp2;
1006 	int synced;
1007 
1008 	/* check if all the ports have synchronized again */
1009 	if (!bs->bs_allsynced) {
1010 		synced = 1;
1011 		LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1012 			if (!(bp2->bp_synced ||
1013 			     bp2->bp_role == BSTP_ROLE_ROOT)) {
1014 				synced = 0;
1015 				break;
1016 			}
1017 		}
1018 		bs->bs_allsynced = synced;
1019 	}
1020 
1021 	bstp_update_roles(bs, bp);
1022 	bstp_update_tc(bp);
1023 }
1024 
1025 void
1026 bstp_update_roles(struct bstp_state *bs, struct bstp_port *bp)
1027 {
1028 	switch (bp->bp_role) {
1029 	case BSTP_ROLE_DISABLED:
1030 		/* Clear any flags if set */
1031 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
1032 			bp->bp_sync = 0;
1033 			bp->bp_synced = 1;
1034 			bp->bp_reroot = 0;
1035 		}
1036 		break;
1037 
1038 	case BSTP_ROLE_ALTERNATE:
1039 	case BSTP_ROLE_BACKUP:
1040 		if ((bs->bs_allsynced && !bp->bp_agree) ||
1041 		    (bp->bp_proposed && bp->bp_agree)) {
1042 			bp->bp_proposed = 0;
1043 			bp->bp_agree = 1;
1044 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1045 			DPRINTF("%s -> ALTERNATE_AGREED\n",
1046 			    bp->bp_ifp->if_xname);
1047 		}
1048 
1049 		if (bp->bp_proposed && !bp->bp_agree) {
1050 			bstp_set_all_sync(bs);
1051 			bp->bp_proposed = 0;
1052 			DPRINTF("%s -> ALTERNATE_PROPOSED\n",
1053 			    bp->bp_ifp->if_xname);
1054 		}
1055 
1056 		/* Clear any flags if set */
1057 		if (bp->bp_sync || !bp->bp_synced || bp->bp_reroot) {
1058 			bp->bp_sync = 0;
1059 			bp->bp_synced = 1;
1060 			bp->bp_reroot = 0;
1061 			DPRINTF("%s -> ALTERNATE_PORT\n", bp->bp_ifp->if_xname);
1062 		}
1063 		break;
1064 
1065 	case BSTP_ROLE_ROOT:
1066 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING && !bp->bp_reroot) {
1067 			bstp_set_all_reroot(bs);
1068 			DPRINTF("%s -> ROOT_REROOT\n", bp->bp_ifp->if_xname);
1069 		}
1070 
1071 		if ((bs->bs_allsynced && !bp->bp_agree) ||
1072 		    (bp->bp_proposed && bp->bp_agree)) {
1073 			bp->bp_proposed = 0;
1074 			bp->bp_sync = 0;
1075 			bp->bp_agree = 1;
1076 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1077 			DPRINTF("%s -> ROOT_AGREED\n", bp->bp_ifp->if_xname);
1078 		}
1079 
1080 		if (bp->bp_proposed && !bp->bp_agree) {
1081 			bstp_set_all_sync(bs);
1082 			bp->bp_proposed = 0;
1083 			DPRINTF("%s -> ROOT_PROPOSED\n", bp->bp_ifp->if_xname);
1084 		}
1085 
1086 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1087 		    (bp->bp_forward_delay_timer.active == 0 ||
1088 		    (bstp_rerooted(bs, bp) &&
1089 		    bp->bp_recent_backup_timer.active == 0 &&
1090 		    bp->bp_protover == BSTP_PROTO_RSTP))) {
1091 			switch (bp->bp_state) {
1092 			case BSTP_IFSTATE_DISCARDING:
1093 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
1094 				break;
1095 			case BSTP_IFSTATE_LEARNING:
1096 				bstp_set_port_state(bp,
1097 				    BSTP_IFSTATE_FORWARDING);
1098 				break;
1099 			}
1100 		}
1101 
1102 		if (bp->bp_state == BSTP_IFSTATE_FORWARDING && bp->bp_reroot) {
1103 			bp->bp_reroot = 0;
1104 			DPRINTF("%s -> ROOT_REROOTED\n", bp->bp_ifp->if_xname);
1105 		}
1106 		break;
1107 
1108 	case BSTP_ROLE_DESIGNATED:
1109 		if (bp->bp_recent_root_timer.active == 0 && bp->bp_reroot) {
1110 			bp->bp_reroot = 0;
1111 			DPRINTF("%s -> DESIGNATED_RETIRED\n",
1112 			    bp->bp_ifp->if_xname);
1113 		}
1114 
1115 		if ((bp->bp_state == BSTP_IFSTATE_DISCARDING &&
1116 		    !bp->bp_synced) || (bp->bp_agreed && !bp->bp_synced) ||
1117 		    (bp->bp_operedge && !bp->bp_synced) ||
1118 		    (bp->bp_sync && bp->bp_synced)) {
1119 			bstp_timer_stop(&bp->bp_recent_root_timer);
1120 			bp->bp_synced = 1;
1121 			bp->bp_sync = 0;
1122 			DPRINTF("%s -> DESIGNATED_SYNCED\n",
1123 			    bp->bp_ifp->if_xname);
1124 		}
1125 
1126 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1127 		    !bp->bp_agreed && !bp->bp_proposing &&
1128 		    !bp->bp_operedge) {
1129 			bp->bp_proposing = 1;
1130 			bp->bp_flags |= BSTP_PORT_NEWINFO;
1131 			bstp_timer_start(&bp->bp_edge_delay_timer,
1132 			    (bp->bp_ptp_link ? BSTP_DEFAULT_MIGRATE_DELAY :
1133 			     bp->bp_desg_max_age));
1134 			DPRINTF("%s -> DESIGNATED_PROPOSE\n",
1135 			    bp->bp_ifp->if_xname);
1136 		}
1137 
1138 		if (bp->bp_state != BSTP_IFSTATE_FORWARDING &&
1139 		    (bp->bp_forward_delay_timer.active == 0 || bp->bp_agreed ||
1140 		    bp->bp_operedge) &&
1141 		    (bp->bp_recent_root_timer.active == 0 || !bp->bp_reroot) &&
1142 		    !bp->bp_sync) {
1143 			if (bp->bp_agreed)
1144 				DPRINTF("%s -> AGREED\n", bp->bp_ifp->if_xname);
1145 			/*
1146 			 * If agreed|operedge then go straight to forwarding,
1147 			 * otherwise follow discard -> learn -> forward.
1148 			 */
1149 			if (bp->bp_agreed || bp->bp_operedge ||
1150 			    bp->bp_state == BSTP_IFSTATE_LEARNING) {
1151 				bstp_set_port_state(bp,
1152 				    BSTP_IFSTATE_FORWARDING);
1153 				bp->bp_agreed = bp->bp_protover;
1154 			} else if (bp->bp_state == BSTP_IFSTATE_DISCARDING)
1155 				bstp_set_port_state(bp, BSTP_IFSTATE_LEARNING);
1156 		}
1157 
1158 		if (((bp->bp_sync && !bp->bp_synced) ||
1159 		    (bp->bp_reroot && bp->bp_recent_root_timer.active) ||
1160 		    (bp->bp_flags & BSTP_PORT_DISPUTED)) && !bp->bp_operedge &&
1161 		    bp->bp_state != BSTP_IFSTATE_DISCARDING) {
1162 			bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1163 			bp->bp_flags &= ~BSTP_PORT_DISPUTED;
1164 			bstp_timer_start(&bp->bp_forward_delay_timer,
1165 			    bp->bp_protover == BSTP_PROTO_RSTP ?
1166 			    bp->bp_desg_htime : bp->bp_desg_fdelay);
1167 			DPRINTF("%s -> DESIGNATED_DISCARD\n",
1168 			    bp->bp_ifp->if_xname);
1169 		}
1170 		break;
1171 	}
1172 
1173 	if (bp->bp_flags & BSTP_PORT_NEWINFO)
1174 		bstp_transmit(bs, bp);
1175 }
1176 
1177 void
1178 bstp_update_tc(struct bstp_port *bp)
1179 {
1180 	switch (bp->bp_tcstate) {
1181 	case BSTP_TCSTATE_ACTIVE:
1182 		if ((bp->bp_role != BSTP_ROLE_DESIGNATED &&
1183 		    bp->bp_role != BSTP_ROLE_ROOT) || bp->bp_operedge)
1184 			bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1185 
1186 		if (bp->bp_rcvdtcn)
1187 			bstp_set_port_tc(bp, BSTP_TCSTATE_TCN);
1188 		if (bp->bp_rcvdtc)
1189 			bstp_set_port_tc(bp, BSTP_TCSTATE_TC);
1190 
1191 		if (bp->bp_tc_prop && !bp->bp_operedge)
1192 			bstp_set_port_tc(bp, BSTP_TCSTATE_PROPAG);
1193 
1194 		if (bp->bp_rcvdtca)
1195 			bstp_set_port_tc(bp, BSTP_TCSTATE_ACK);
1196 		break;
1197 
1198 	case BSTP_TCSTATE_INACTIVE:
1199 		if ((bp->bp_state == BSTP_IFSTATE_LEARNING ||
1200 		    bp->bp_state == BSTP_IFSTATE_FORWARDING) &&
1201 		    bp->bp_fdbflush == 0)
1202 			bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1203 		break;
1204 
1205 	case BSTP_TCSTATE_LEARNING:
1206 		if (bp->bp_rcvdtc || bp->bp_rcvdtcn || bp->bp_rcvdtca ||
1207 		    bp->bp_tc_prop)
1208 			bstp_set_port_tc(bp, BSTP_TCSTATE_LEARNING);
1209 		else if (bp->bp_role != BSTP_ROLE_DESIGNATED &&
1210 			 bp->bp_role != BSTP_ROLE_ROOT &&
1211 			 bp->bp_state == BSTP_IFSTATE_DISCARDING)
1212 			bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1213 
1214 		if ((bp->bp_role == BSTP_ROLE_DESIGNATED ||
1215 		    bp->bp_role == BSTP_ROLE_ROOT) &&
1216 		    bp->bp_state == BSTP_IFSTATE_FORWARDING &&
1217 		    !bp->bp_operedge)
1218 			bstp_set_port_tc(bp, BSTP_TCSTATE_DETECTED);
1219 		break;
1220 
1221 	/* these are transient states and go straight back to ACTIVE */
1222 	case BSTP_TCSTATE_DETECTED:
1223 	case BSTP_TCSTATE_TCN:
1224 	case BSTP_TCSTATE_TC:
1225 	case BSTP_TCSTATE_PROPAG:
1226 	case BSTP_TCSTATE_ACK:
1227 		DPRINTF("Invalid TC state for %s\n",
1228 		    bp->bp_ifp->if_xname);
1229 		break;
1230 	}
1231 
1232 }
1233 
1234 void
1235 bstp_update_info(struct bstp_port *bp)
1236 {
1237 	struct bstp_state *bs = bp->bp_bs;
1238 
1239 	bp->bp_proposing = 0;
1240 	bp->bp_proposed = 0;
1241 
1242 	if (bp->bp_agreed && !bstp_pdu_bettersame(bp, BSTP_INFO_MINE))
1243 		bp->bp_agreed = 0;
1244 
1245 	if (bp->bp_synced && !bp->bp_agreed) {
1246 		bp->bp_synced = 0;
1247 		bs->bs_allsynced = 0;
1248 	}
1249 
1250 	/* copy the designated pv to the port */
1251 	bp->bp_port_pv = bp->bp_desg_pv;
1252 	bp->bp_port_msg_age = bp->bp_desg_msg_age;
1253 	bp->bp_port_max_age = bp->bp_desg_max_age;
1254 	bp->bp_port_fdelay = bp->bp_desg_fdelay;
1255 	bp->bp_port_htime = bp->bp_desg_htime;
1256 	bp->bp_infois = BSTP_INFO_MINE;
1257 
1258 	/* Set transmit flag but do not immediately send */
1259 	bp->bp_flags |= BSTP_PORT_NEWINFO;
1260 }
1261 
1262 /* set tcprop on every port other than the caller */
1263 void
1264 bstp_set_other_tcprop(struct bstp_port *bp)
1265 {
1266 	struct bstp_state *bs = bp->bp_bs;
1267 	struct bstp_port *bp2;
1268 
1269 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1270 		if (bp2 == bp)
1271 			continue;
1272 		bp2->bp_tc_prop = 1;
1273 	}
1274 }
1275 
1276 void
1277 bstp_set_all_reroot(struct bstp_state *bs)
1278 {
1279 	struct bstp_port *bp;
1280 
1281 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1282 		bp->bp_reroot = 1;
1283 }
1284 
1285 void
1286 bstp_set_all_sync(struct bstp_state *bs)
1287 {
1288 	struct bstp_port *bp;
1289 
1290 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1291 		bp->bp_sync = 1;
1292 		bp->bp_synced = 0;	/* Not explicit in spec */
1293 	}
1294 
1295 	bs->bs_allsynced = 0;
1296 }
1297 
1298 void
1299 bstp_set_port_state(struct bstp_port *bp, int state)
1300 {
1301 	if (bp->bp_state == state)
1302 		return;
1303 
1304 	bp->bp_state = state;
1305 
1306 	switch (bp->bp_state) {
1307 	case BSTP_IFSTATE_DISCARDING:
1308 		DPRINTF("state changed to DISCARDING on %s\n",
1309 		    bp->bp_ifp->if_xname);
1310 		break;
1311 
1312 	case BSTP_IFSTATE_LEARNING:
1313 		DPRINTF("state changed to LEARNING on %s\n",
1314 		    bp->bp_ifp->if_xname);
1315 
1316 		bstp_timer_start(&bp->bp_forward_delay_timer,
1317 		    bp->bp_protover == BSTP_PROTO_RSTP ?
1318 		    bp->bp_desg_htime : bp->bp_desg_fdelay);
1319 		break;
1320 
1321 	case BSTP_IFSTATE_FORWARDING:
1322 		DPRINTF("state changed to FORWARDING on %s\n",
1323 		    bp->bp_ifp->if_xname);
1324 
1325 		bstp_timer_stop(&bp->bp_forward_delay_timer);
1326 		/* Record that we enabled forwarding */
1327 		bp->bp_forward_transitions++;
1328 		break;
1329 	}
1330 }
1331 
1332 void
1333 bstp_set_port_role(struct bstp_port *bp, int role)
1334 {
1335 	struct bstp_state *bs = bp->bp_bs;
1336 
1337 	if (bp->bp_role == role)
1338 		return;
1339 
1340 	/* perform pre-change tasks */
1341 	switch (bp->bp_role) {
1342 	case BSTP_ROLE_DISABLED:
1343 		bstp_timer_start(&bp->bp_forward_delay_timer,
1344 		    bp->bp_desg_max_age);
1345 		break;
1346 
1347 	case BSTP_ROLE_BACKUP:
1348 		bstp_timer_start(&bp->bp_recent_backup_timer,
1349 		    bp->bp_desg_htime * 2);
1350 		/* FALLTHROUGH */
1351 	case BSTP_ROLE_ALTERNATE:
1352 		bstp_timer_start(&bp->bp_forward_delay_timer,
1353 		    bp->bp_desg_fdelay);
1354 		bp->bp_sync = 0;
1355 		bp->bp_synced = 1;
1356 		bp->bp_reroot = 0;
1357 		break;
1358 
1359 	case BSTP_ROLE_ROOT:
1360 		bstp_timer_start(&bp->bp_recent_root_timer,
1361 		    BSTP_DEFAULT_FORWARD_DELAY);
1362 		break;
1363 	}
1364 
1365 	bp->bp_role = role;
1366 	/* clear values not carried between roles */
1367 	bp->bp_proposing = 0;
1368 	bs->bs_allsynced = 0;
1369 
1370 	/* initialise the new role */
1371 	switch (bp->bp_role) {
1372 	case BSTP_ROLE_DISABLED:
1373 	case BSTP_ROLE_ALTERNATE:
1374 	case BSTP_ROLE_BACKUP:
1375 		DPRINTF("%s role -> ALT/BACK/DISABLED\n",
1376 		    bp->bp_ifp->if_xname);
1377 		bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1378 		bstp_timer_stop(&bp->bp_recent_root_timer);
1379 		bstp_timer_latch(&bp->bp_forward_delay_timer);
1380 		bp->bp_sync = 0;
1381 		bp->bp_synced = 1;
1382 		bp->bp_reroot = 0;
1383 		break;
1384 
1385 	case BSTP_ROLE_ROOT:
1386 		DPRINTF("%s role -> ROOT\n",
1387 		    bp->bp_ifp->if_xname);
1388 		bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1389 		bstp_timer_latch(&bp->bp_recent_root_timer);
1390 		bp->bp_proposing = 0;
1391 		break;
1392 
1393 	case BSTP_ROLE_DESIGNATED:
1394 		DPRINTF("%s role -> DESIGNATED\n",
1395 		    bp->bp_ifp->if_xname);
1396 		bstp_timer_start(&bp->bp_hello_timer,
1397 		    bp->bp_desg_htime);
1398 		bp->bp_agree = 0;
1399 		break;
1400 	}
1401 
1402 	/* let the TC state know that the role changed */
1403 	bstp_update_tc(bp);
1404 }
1405 
1406 void
1407 bstp_set_port_proto(struct bstp_port *bp, int proto)
1408 {
1409 	struct bstp_state *bs = bp->bp_bs;
1410 
1411 	/* supported protocol versions */
1412 	switch (proto) {
1413 	case BSTP_PROTO_STP:
1414 		/* we can downgrade protocols only */
1415 		bstp_timer_stop(&bp->bp_migrate_delay_timer);
1416 		/* clear unsupported features */
1417 		bp->bp_operedge = 0;
1418 		break;
1419 
1420 	case BSTP_PROTO_RSTP:
1421 		bstp_timer_start(&bp->bp_migrate_delay_timer,
1422 		    bs->bs_migration_delay);
1423 		break;
1424 
1425 	default:
1426 		DPRINTF("Unsupported STP version %d\n", proto);
1427 		return;
1428 	}
1429 
1430 	bp->bp_protover = proto;
1431 	bp->bp_flags &= ~BSTP_PORT_CANMIGRATE;
1432 }
1433 
1434 void
1435 bstp_set_port_tc(struct bstp_port *bp, int state)
1436 {
1437 	struct bstp_state *bs = bp->bp_bs;
1438 
1439 	bp->bp_tcstate = state;
1440 
1441 	/* initialise the new state */
1442 	switch (bp->bp_tcstate) {
1443 	case BSTP_TCSTATE_ACTIVE:
1444 		DPRINTF("%s -> TC_ACTIVE\n", bp->bp_ifp->if_xname);
1445 		/* nothing to do */
1446 		break;
1447 
1448 	case BSTP_TCSTATE_INACTIVE:
1449 		bstp_timer_stop(&bp->bp_tc_timer);
1450 		/* flush routes on the parent bridge */
1451 		bp->bp_fdbflush = 1;
1452 		bstp_notify_rtage(bp, 0);
1453 		bp->bp_tc_ack = 0;
1454 		DPRINTF("%s -> TC_INACTIVE\n", bp->bp_ifp->if_xname);
1455 		break;
1456 
1457 	case BSTP_TCSTATE_LEARNING:
1458 		bp->bp_rcvdtc = 0;
1459 		bp->bp_rcvdtcn = 0;
1460 		bp->bp_rcvdtca = 0;
1461 		bp->bp_tc_prop = 0;
1462 		DPRINTF("%s -> TC_LEARNING\n", bp->bp_ifp->if_xname);
1463 		break;
1464 
1465 	case BSTP_TCSTATE_DETECTED:
1466 		bstp_set_timer_tc(bp);
1467 		bstp_set_other_tcprop(bp);
1468 		/* send out notification */
1469 		bp->bp_flags |= BSTP_PORT_NEWINFO;
1470 		bstp_transmit(bs, bp);
1471 		getmicrotime(&bs->bs_last_tc_time);
1472 		DPRINTF("%s -> TC_DETECTED\n", bp->bp_ifp->if_xname);
1473 		bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1474 		break;
1475 
1476 	case BSTP_TCSTATE_TCN:
1477 		bstp_set_timer_tc(bp);
1478 		DPRINTF("%s -> TC_TCN\n", bp->bp_ifp->if_xname);
1479 		/* FALLTHROUGH */
1480 	case BSTP_TCSTATE_TC:
1481 		bp->bp_rcvdtc = 0;
1482 		bp->bp_rcvdtcn = 0;
1483 		if (bp->bp_role == BSTP_ROLE_DESIGNATED)
1484 			bp->bp_tc_ack = 1;
1485 
1486 		bstp_set_other_tcprop(bp);
1487 		DPRINTF("%s -> TC_TC\n", bp->bp_ifp->if_xname);
1488 		bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1489 		break;
1490 
1491 	case BSTP_TCSTATE_PROPAG:
1492 		/* flush routes on the parent bridge */
1493 		bp->bp_fdbflush = 1;
1494 		bstp_notify_rtage(bp, 0);
1495 		bp->bp_tc_prop = 0;
1496 		bstp_set_timer_tc(bp);
1497 		DPRINTF("%s -> TC_PROPAG\n", bp->bp_ifp->if_xname);
1498 		bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1499 		break;
1500 
1501 	case BSTP_TCSTATE_ACK:
1502 		bstp_timer_stop(&bp->bp_tc_timer);
1503 		bp->bp_rcvdtca = 0;
1504 		DPRINTF("%s -> TC_ACK\n", bp->bp_ifp->if_xname);
1505 		bp->bp_tcstate = BSTP_TCSTATE_ACTIVE; /* UCT */
1506 		break;
1507 	}
1508 }
1509 
1510 void
1511 bstp_set_timer_tc(struct bstp_port *bp)
1512 {
1513 	struct bstp_state *bs = bp->bp_bs;
1514 
1515 	if (bp->bp_tc_timer.active)
1516 		return;
1517 
1518 	switch (bp->bp_protover) {
1519 	case BSTP_PROTO_RSTP:
1520 		bstp_timer_start(&bp->bp_tc_timer,
1521 		    bp->bp_desg_htime + BSTP_TICK_VAL);
1522 		bp->bp_flags |= BSTP_PORT_NEWINFO;
1523 		break;
1524 	case BSTP_PROTO_STP:
1525 		bstp_timer_start(&bp->bp_tc_timer,
1526 		    bs->bs_root_max_age + bs->bs_root_fdelay);
1527 		break;
1528 	}
1529 }
1530 
1531 void
1532 bstp_set_timer_msgage(struct bstp_port *bp)
1533 {
1534 	if (bp->bp_port_msg_age + BSTP_MESSAGE_AGE_INCR <=
1535 	    bp->bp_port_max_age) {
1536 		bstp_timer_start(&bp->bp_message_age_timer,
1537 		    bp->bp_port_htime * 3);
1538 	} else
1539 		/* expires immediately */
1540 		bstp_timer_start(&bp->bp_message_age_timer, 0);
1541 }
1542 
1543 int
1544 bstp_rerooted(struct bstp_state *bs, struct bstp_port *bp)
1545 {
1546 	struct bstp_port *bp2;
1547 	int rr_set = 0;
1548 
1549 	LIST_FOREACH(bp2, &bs->bs_bplist, bp_next) {
1550 		if (bp2 == bp)
1551 			continue;
1552 		if (bp2->bp_recent_root_timer.active) {
1553 			rr_set = 1;
1554 			break;
1555 		}
1556 	}
1557 	return (!rr_set);
1558 }
1559 
1560 /*
1561  * Calculate the path cost according to the link speed.
1562  */
1563 u_int32_t
1564 bstp_calc_path_cost(struct bstp_port *bp)
1565 {
1566 	struct ifnet *ifp = bp->bp_ifp;
1567 	u_int32_t path_cost;
1568 
1569 	/* If the priority has been manually set then retain the value */
1570 	if (bp->bp_flags & BSTP_PORT_ADMCOST)
1571 		return bp->bp_path_cost;
1572 
1573 	if (ifp->if_baudrate < 1000)
1574 		return (BSTP_DEFAULT_PATH_COST);
1575 
1576  	/* formula from section 17.14, IEEE Std 802.1D-2004 */
1577 	path_cost = 20000000000ULL / (ifp->if_baudrate / 1000);
1578 
1579 	if (path_cost > BSTP_MAX_PATH_COST)
1580 		path_cost = BSTP_MAX_PATH_COST;
1581 
1582 	/* STP compat mode only uses 16 bits of the 32 */
1583 	if (bp->bp_protover == BSTP_PROTO_STP && path_cost > 65535)
1584 		path_cost = 65535;
1585 
1586 	return (path_cost);
1587 }
1588 
1589 void
1590 bstp_notify_rtage(struct bstp_port *bp, int pending)
1591 {
1592 	int age = 0;
1593 
1594 	KERNEL_ASSERT_LOCKED();
1595 
1596 	switch (bp->bp_protover) {
1597 	case BSTP_PROTO_STP:
1598 		/* convert to seconds */
1599 		age = bp->bp_desg_fdelay / BSTP_TICK_VAL;
1600 		break;
1601 	case BSTP_PROTO_RSTP:
1602 		age = 0;
1603 		break;
1604 	}
1605 
1606 	if (bp->bp_active == 1)
1607 		bridge_rtagenode(bp->bp_ifp, age);
1608 
1609 	/* flush is complete */
1610 	bp->bp_fdbflush = 0;
1611 }
1612 
1613 void
1614 bstp_ifstate(void *arg)
1615 {
1616 	struct ifnet *ifp = (struct ifnet *)arg;
1617 	struct bridge_iflist *bif;
1618 	struct bstp_port *bp;
1619 	struct bstp_state *bs;
1620 	int s;
1621 
1622 	if (ifp->if_type == IFT_BRIDGE)
1623 		return;
1624 
1625 	s = splnet();
1626 	if ((bif = bridge_getbif(ifp)) == NULL)
1627 		goto done;
1628 	if ((bif->bif_flags & IFBIF_STP) == 0)
1629 		goto done;
1630 	if ((bp = bif->bif_stp) == NULL)
1631 		goto done;
1632 	if ((bs = bp->bp_bs) == NULL)
1633 		goto done;
1634 
1635 	/* update the link state */
1636 	bstp_ifupdstatus(bs, bp);
1637 	bstp_update_state(bs, bp);
1638  done:
1639 	splx(s);
1640 }
1641 
1642 void
1643 bstp_ifupdstatus(struct bstp_state *bs, struct bstp_port *bp)
1644 {
1645 	struct ifnet *ifp = bp->bp_ifp;
1646 
1647 	if (ifp == NULL)
1648 		return;
1649 
1650 	bp->bp_path_cost = bstp_calc_path_cost(bp);
1651 
1652 	if ((ifp->if_flags & IFF_UP) &&
1653 	    ifp->if_link_state != LINK_STATE_DOWN) {
1654 		if (bp->bp_flags & BSTP_PORT_AUTOPTP) {
1655 			/* A full-duplex link is assumed to be ptp */
1656 			bp->bp_ptp_link = ifp->if_link_state ==
1657 			    LINK_STATE_FULL_DUPLEX ? 1 : 0;
1658 		}
1659 
1660 		if (bp->bp_infois == BSTP_INFO_DISABLED)
1661 			bstp_enable_port(bs, bp);
1662 	} else {
1663 		if (bp->bp_infois != BSTP_INFO_DISABLED)
1664 			bstp_disable_port(bs, bp);
1665 	}
1666 }
1667 
1668 void
1669 bstp_enable_port(struct bstp_state *bs, struct bstp_port *bp)
1670 {
1671 	bp->bp_infois = BSTP_INFO_AGED;
1672 	bstp_assign_roles(bs);
1673 }
1674 
1675 void
1676 bstp_disable_port(struct bstp_state *bs, struct bstp_port *bp)
1677 {
1678 	bp->bp_infois = BSTP_INFO_DISABLED;
1679 	bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1680 	bstp_assign_roles(bs);
1681 }
1682 
1683 void
1684 bstp_tick(void *arg)
1685 {
1686 	struct bstp_state *bs = (struct bstp_state *)arg;
1687 	struct bstp_port *bp;
1688 	int s;
1689 
1690 	s = splnet();
1691 	if ((bs->bs_ifflags & IFF_RUNNING) == 0) {
1692 		splx(s);
1693 		return;
1694 	}
1695 
1696 	/* slow timer to catch missed link events */
1697 	if (bstp_timer_expired(&bs->bs_link_timer)) {
1698 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1699 			bstp_ifupdstatus(bs, bp);
1700 		bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
1701 	}
1702 
1703 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1704 		/* no events need to happen for these */
1705 		bstp_timer_expired(&bp->bp_tc_timer);
1706 		bstp_timer_expired(&bp->bp_recent_root_timer);
1707 		bstp_timer_expired(&bp->bp_forward_delay_timer);
1708 		bstp_timer_expired(&bp->bp_recent_backup_timer);
1709 
1710 		if (bstp_timer_expired(&bp->bp_hello_timer))
1711 			bstp_hello_timer_expiry(bs, bp);
1712 
1713 		if (bstp_timer_expired(&bp->bp_message_age_timer))
1714 			bstp_message_age_expiry(bs, bp);
1715 
1716 		if (bstp_timer_expired(&bp->bp_migrate_delay_timer))
1717 			bstp_migrate_delay_expiry(bs, bp);
1718 
1719 		if (bstp_timer_expired(&bp->bp_edge_delay_timer))
1720 			bstp_edge_delay_expiry(bs, bp);
1721 
1722 		/* update the various state machines for the port */
1723 		bstp_update_state(bs, bp);
1724 
1725 		if (bp->bp_txcount > 0)
1726 			bp->bp_txcount--;
1727 	}
1728 
1729 	if (bs->bs_ifp->if_flags & IFF_RUNNING)
1730 		timeout_add_sec(&bs->bs_bstptimeout, 1);
1731 
1732 	splx(s);
1733 }
1734 
1735 void
1736 bstp_timer_start(struct bstp_timer *t, u_int16_t v)
1737 {
1738 	t->value = v;
1739 	t->active = 1;
1740 	t->latched = 0;
1741 }
1742 
1743 void
1744 bstp_timer_stop(struct bstp_timer *t)
1745 {
1746 	t->value = 0;
1747 	t->active = 0;
1748 	t->latched = 0;
1749 }
1750 
1751 void
1752 bstp_timer_latch(struct bstp_timer *t)
1753 {
1754 	t->latched = 1;
1755 	t->active = 1;
1756 }
1757 
1758 int
1759 bstp_timer_expired(struct bstp_timer *t)
1760 {
1761 	if (t->active == 0 || t->latched)
1762 		return (0);
1763 	t->value -= BSTP_TICK_VAL;
1764 	if (t->value <= 0) {
1765 		bstp_timer_stop(t);
1766 		return (1);
1767 	}
1768 	return (0);
1769 }
1770 
1771 void
1772 bstp_hello_timer_expiry(struct bstp_state *bs, struct bstp_port *bp)
1773 {
1774 	if ((bp->bp_flags & BSTP_PORT_NEWINFO) ||
1775 	    bp->bp_role == BSTP_ROLE_DESIGNATED ||
1776 	    (bp->bp_role == BSTP_ROLE_ROOT &&
1777 	     bp->bp_tc_timer.active == 1)) {
1778 		bstp_timer_start(&bp->bp_hello_timer, bp->bp_desg_htime);
1779 		bp->bp_flags |= BSTP_PORT_NEWINFO;
1780 		bstp_transmit(bs, bp);
1781 	}
1782 }
1783 
1784 void
1785 bstp_message_age_expiry(struct bstp_state *bs, struct bstp_port *bp)
1786 {
1787 	if (bp->bp_infois == BSTP_INFO_RECEIVED) {
1788 		bp->bp_infois = BSTP_INFO_AGED;
1789 		bstp_assign_roles(bs);
1790 		DPRINTF("aged info on %s\n", bp->bp_ifp->if_xname);
1791 	}
1792 }
1793 
1794 void
1795 bstp_migrate_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1796 {
1797 	bp->bp_flags |= BSTP_PORT_CANMIGRATE;
1798 }
1799 
1800 void
1801 bstp_edge_delay_expiry(struct bstp_state *bs, struct bstp_port *bp)
1802 {
1803 	if ((bp->bp_flags & BSTP_PORT_AUTOEDGE) &&
1804 	    bp->bp_protover == BSTP_PROTO_RSTP && bp->bp_proposing &&
1805 	    bp->bp_role == BSTP_ROLE_DESIGNATED)
1806 		bp->bp_operedge = 1;
1807 }
1808 
1809 int
1810 bstp_addr_cmp(const u_int8_t *a, const u_int8_t *b)
1811 {
1812 	int i, d;
1813 
1814 	for (i = 0, d = 0; i < ETHER_ADDR_LEN && d == 0; i++) {
1815 		d = ((int)a[i]) - ((int)b[i]);
1816 	}
1817 
1818 	return (d);
1819 }
1820 
1821 /*
1822  * compare the bridge address component of the bridgeid
1823  */
1824 int
1825 bstp_same_bridgeid(u_int64_t id1, u_int64_t id2)
1826 {
1827 	u_char addr1[ETHER_ADDR_LEN];
1828 	u_char addr2[ETHER_ADDR_LEN];
1829 
1830 	PV2ADDR(id1, addr1);
1831 	PV2ADDR(id2, addr2);
1832 
1833 	if (bstp_addr_cmp(addr1, addr2) == 0)
1834 		return (1);
1835 
1836 	return (0);
1837 }
1838 
1839 void
1840 bstp_initialization(struct bstp_state *bs)
1841 {
1842 	struct bstp_port *bp;
1843 	struct ifnet *mif = NULL;
1844 	u_char *e_addr;
1845 
1846 	if (LIST_EMPTY(&bs->bs_bplist)) {
1847 		bstp_stop(bs);
1848 		bstp_reset(bs);
1849 		return;
1850 	}
1851 
1852 	/*
1853 	 * Search through the Ethernet interfaces and find the one
1854 	 * with the lowest value.
1855 	 * Make sure we take the address from an interface that is
1856 	 * part of the bridge to make sure two bridges on the system
1857 	 * will not use the same one. It is not possible for mif to be
1858 	 * null, at this point we have at least one STP port and hence
1859 	 * at least one NIC.
1860 	 */
1861 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1862 		if (mif == NULL) {
1863 			mif = bp->bp_ifp;
1864 			continue;
1865 		}
1866 		if (bstp_addr_cmp(LLADDR(bp->bp_ifp->if_sadl),
1867 		    LLADDR(mif->if_sadl)) < 0) {
1868 			mif = bp->bp_ifp;
1869 			continue;
1870 		}
1871 	}
1872 
1873 	e_addr = LLADDR(mif->if_sadl);
1874 	bs->bs_bridge_pv.pv_dbridge_id =
1875 	    (((u_int64_t)bs->bs_bridge_priority) << 48) |
1876 	    (((u_int64_t)e_addr[0]) << 40) |
1877 	    (((u_int64_t)e_addr[1]) << 32) |
1878 	    (((u_int64_t)e_addr[2]) << 24) |
1879 	    (((u_int64_t)e_addr[3]) << 16) |
1880 	    (((u_int64_t)e_addr[4]) << 8) |
1881 	    (((u_int64_t)e_addr[5]));
1882 
1883 	bs->bs_bridge_pv.pv_root_id = bs->bs_bridge_pv.pv_dbridge_id;
1884 	bs->bs_bridge_pv.pv_cost = 0;
1885 	bs->bs_bridge_pv.pv_dport_id = 0;
1886 	bs->bs_bridge_pv.pv_port_id = 0;
1887 
1888 	if (!timeout_initialized(&bs->bs_bstptimeout))
1889 		timeout_set(&bs->bs_bstptimeout, bstp_tick, bs);
1890 	if (!timeout_pending(&bs->bs_bstptimeout))
1891 		timeout_add_sec(&bs->bs_bstptimeout, 1);
1892 
1893 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
1894 		bp->bp_port_id = (bp->bp_priority << 8) |
1895 		    (bp->bp_ifp->if_index & 0xfff);
1896 		bstp_ifupdstatus(bs, bp);
1897 	}
1898 
1899 	bstp_assign_roles(bs);
1900 	bstp_timer_start(&bs->bs_link_timer, BSTP_LINK_TIMER);
1901 }
1902 
1903 struct bstp_state *
1904 bstp_create(struct ifnet *ifp)
1905 {
1906 	struct bstp_state *bs;
1907 
1908 	bs = malloc(sizeof(*bs), M_DEVBUF, M_WAITOK|M_ZERO);
1909 	LIST_INIT(&bs->bs_bplist);
1910 
1911 	bs->bs_ifp = ifp;
1912 	bs->bs_bridge_max_age = BSTP_DEFAULT_MAX_AGE;
1913 	bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
1914 	bs->bs_bridge_fdelay = BSTP_DEFAULT_FORWARD_DELAY;
1915 	bs->bs_bridge_priority = BSTP_DEFAULT_BRIDGE_PRIORITY;
1916 	bs->bs_hold_time = BSTP_DEFAULT_HOLD_TIME;
1917 	bs->bs_migration_delay = BSTP_DEFAULT_MIGRATE_DELAY;
1918 	bs->bs_txholdcount = BSTP_DEFAULT_HOLD_COUNT;
1919 	bs->bs_protover = BSTP_PROTO_RSTP;	/* STP instead of RSTP? */
1920 
1921 	getmicrotime(&bs->bs_last_tc_time);
1922 
1923 	return (bs);
1924 }
1925 
1926 void
1927 bstp_destroy(struct bstp_state *bs)
1928 {
1929 	if (bs == NULL)
1930 		return;
1931 
1932 	if (!LIST_EMPTY(&bs->bs_bplist))
1933 		panic("bstp still active");
1934 
1935 	free(bs, M_DEVBUF, sizeof *bs);
1936 }
1937 
1938 void
1939 bstp_stop(struct bstp_state *bs)
1940 {
1941 	struct bstp_port *bp;
1942 
1943 	LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
1944 		bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1945 
1946 	if (timeout_initialized(&bs->bs_bstptimeout))
1947 		timeout_del(&bs->bs_bstptimeout);
1948 }
1949 
1950 struct bstp_port *
1951 bstp_add(struct bstp_state *bs, struct ifnet *ifp)
1952 {
1953 	struct bstp_port *bp;
1954 
1955 	switch (ifp->if_type) {
1956 	case IFT_ETHER:	/* These can do spanning tree. */
1957 		break;
1958 	default:
1959 		/* Nothing else can. */
1960 		return (NULL);
1961 	}
1962 
1963 	bp = malloc(sizeof(*bp), M_DEVBUF, M_NOWAIT|M_ZERO);
1964 	if (bp == NULL)
1965 		return (NULL);
1966 
1967 	bp->bp_ifp = ifp;
1968 	bp->bp_bs = bs;
1969 	bp->bp_priority = BSTP_DEFAULT_PORT_PRIORITY;
1970 	bp->bp_txcount = 0;
1971 
1972 	/* Init state */
1973 	bp->bp_infois = BSTP_INFO_DISABLED;
1974 	bp->bp_flags = BSTP_PORT_AUTOEDGE | BSTP_PORT_AUTOPTP;
1975 	bstp_set_port_state(bp, BSTP_IFSTATE_DISCARDING);
1976 	bstp_set_port_proto(bp, bs->bs_protover);
1977 	bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
1978 	bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
1979 	bp->bp_path_cost = bstp_calc_path_cost(bp);
1980 
1981 	LIST_INSERT_HEAD(&bs->bs_bplist, bp, bp_next);
1982 
1983 	bp->bp_active = 1;
1984 	bp->bp_flags |= BSTP_PORT_NEWINFO;
1985 	bstp_initialization(bs);
1986 	bstp_update_roles(bs, bp);
1987 
1988 	/* Register callback for physical link state changes */
1989 	task_set(&bp->bp_ltask, bstp_ifstate, ifp);
1990 	if_linkstatehook_add(ifp, &bp->bp_ltask);
1991 
1992 	return (bp);
1993 }
1994 
1995 void
1996 bstp_delete(struct bstp_port *bp)
1997 {
1998 	struct bstp_state *bs = bp->bp_bs;
1999 	struct ifnet *ifp = bp->bp_ifp;
2000 
2001 	if (!bp->bp_active)
2002 		panic("not a bstp member");
2003 
2004 	if_linkstatehook_del(ifp, &bp->bp_ltask);
2005 
2006 	LIST_REMOVE(bp, bp_next);
2007 	free(bp, M_DEVBUF, sizeof *bp);
2008 	bstp_initialization(bs);
2009 }
2010 
2011 u_int8_t
2012 bstp_getstate(struct bstp_state *bs, struct bstp_port *bp)
2013 {
2014 	u_int8_t state = bp->bp_state;
2015 
2016 	if (bs->bs_protover != BSTP_PROTO_STP)
2017 		return (state);
2018 
2019 	/*
2020 	 * Translate RSTP roles and states to STP port states
2021 	 * (IEEE Std 802.1D-2004 Table 17-1).
2022 	 */
2023 	if (bp->bp_role == BSTP_ROLE_DISABLED)
2024 		state = BSTP_IFSTATE_DISABLED;
2025 	else if (bp->bp_role == BSTP_ROLE_ALTERNATE ||
2026 	    bp->bp_role == BSTP_ROLE_BACKUP)
2027 		state = BSTP_IFSTATE_BLOCKING;
2028 	else if (state == BSTP_IFSTATE_DISCARDING)
2029 		state = BSTP_IFSTATE_LISTENING;
2030 
2031 	return (state);
2032 }
2033 
2034 void
2035 bstp_ifsflags(struct bstp_port *bp, u_int flags)
2036 {
2037 	struct bstp_state *bs;
2038 
2039 	if ((flags & IFBIF_STP) == 0)
2040 		return;
2041 	bs = bp->bp_bs;
2042 
2043 	/*
2044 	 * Set edge status
2045 	 */
2046 	if (flags & IFBIF_BSTP_AUTOEDGE) {
2047 		if ((bp->bp_flags & BSTP_PORT_AUTOEDGE) == 0) {
2048 			bp->bp_flags |= BSTP_PORT_AUTOEDGE;
2049 
2050 			/* we may be able to transition straight to edge */
2051 			if (bp->bp_edge_delay_timer.active == 0)
2052 				bstp_edge_delay_expiry(bs, bp);
2053 		}
2054 	} else
2055 		bp->bp_flags &= ~BSTP_PORT_AUTOEDGE;
2056 
2057 	if (flags & IFBIF_BSTP_EDGE)
2058 		bp->bp_operedge = 1;
2059 	else
2060 		bp->bp_operedge = 0;
2061 
2062 	/*
2063 	 * Set point to point status
2064 	 */
2065 	if (flags & IFBIF_BSTP_AUTOPTP) {
2066 		if ((bp->bp_flags & BSTP_PORT_AUTOPTP) == 0) {
2067 			bp->bp_flags |= BSTP_PORT_AUTOPTP;
2068 
2069 			bstp_ifupdstatus(bs, bp);
2070 		}
2071 	} else
2072 		bp->bp_flags &= ~BSTP_PORT_AUTOPTP;
2073 
2074 	if (flags & IFBIF_BSTP_PTP)
2075 		bp->bp_ptp_link = 1;
2076 	else
2077 		bp->bp_ptp_link = 0;
2078 }
2079 
2080 int
2081 bstp_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
2082 {
2083 	struct bridge_softc *sc = (struct bridge_softc *)ifp->if_softc;
2084 	struct bstp_state *bs = sc->sc_stp;
2085 	struct ifbrparam *ifbp = (struct ifbrparam *)data;
2086 	struct ifbreq *ifbr = (struct ifbreq *)data;
2087 	struct bridge_iflist *bif;
2088 	struct ifnet *ifs;
2089 	struct bstp_port *bp;
2090 	int r = 0, err = 0, val;
2091 
2092 	switch (cmd) {
2093 	case SIOCBRDGSIFPRIO:
2094 	case SIOCBRDGSIFCOST:
2095 		ifs = ifunit(ifbr->ifbr_ifsname);
2096 		if (ifs == NULL) {
2097 			err = ENOENT;
2098 			break;
2099 		}
2100 		if (ifs->if_bridgeidx != ifp->if_index) {
2101 			err = ESRCH;
2102 			break;
2103 		}
2104 		bif = bridge_getbif(ifs);
2105 		if ((bif->bif_flags & IFBIF_STP) == 0) {
2106 			err = EINVAL;
2107 			break;
2108 		}
2109 		bp = bif->bif_stp;
2110 		break;
2111 	default:
2112 		break;
2113 	}
2114 	if (err)
2115 		return (err);
2116 
2117 	switch (cmd) {
2118 	case SIOCBRDGGPRI:
2119 		ifbp->ifbrp_prio = bs->bs_bridge_priority;
2120 		break;
2121 	case SIOCBRDGSPRI:
2122 		val = ifbp->ifbrp_prio;
2123 		if (val < 0 || val > BSTP_MAX_PRIORITY) {
2124 			err = EINVAL;
2125 			break;
2126 		}
2127 
2128 		/* Limit to steps of 4096 */
2129 		val -= val % 4096;
2130 		bs->bs_bridge_priority = val;
2131 		r = 1;
2132 		break;
2133 	case SIOCBRDGGMA:
2134 		ifbp->ifbrp_maxage = bs->bs_bridge_max_age >> 8;
2135 		break;
2136 	case SIOCBRDGSMA:
2137 		val = ifbp->ifbrp_maxage;
2138 
2139 		/* convert seconds to ticks */
2140 		val *= BSTP_TICK_VAL;
2141 
2142 		if (val < BSTP_MIN_MAX_AGE || val > BSTP_MAX_MAX_AGE) {
2143 			err = EINVAL;
2144 			break;
2145 		}
2146 		bs->bs_bridge_max_age = val;
2147 		r = 1;
2148 		break;
2149 	case SIOCBRDGGHT:
2150 		ifbp->ifbrp_hellotime = bs->bs_bridge_htime >> 8;
2151 		break;
2152 	case SIOCBRDGSHT:
2153 		val = ifbp->ifbrp_hellotime;
2154 
2155 		/* convert seconds to ticks */
2156 		val *=  BSTP_TICK_VAL;
2157 
2158 		/* value can only be changed in leagacy stp mode */
2159 		if (bs->bs_protover != BSTP_PROTO_STP) {
2160 			err = EPERM;
2161 			break;
2162 		}
2163 		if (val < BSTP_MIN_HELLO_TIME || val > BSTP_MAX_HELLO_TIME) {
2164 			err = EINVAL;
2165 			break;
2166 		}
2167 		bs->bs_bridge_htime = val;
2168 		r = 1;
2169 		break;
2170 	case SIOCBRDGGFD:
2171 		ifbp->ifbrp_fwddelay = bs->bs_bridge_fdelay >> 8;
2172 		break;
2173 	case SIOCBRDGSFD:
2174 		val = ifbp->ifbrp_fwddelay;
2175 
2176 		/* convert seconds to ticks */
2177 		val *= BSTP_TICK_VAL;
2178 
2179 		if (val < BSTP_MIN_FORWARD_DELAY ||
2180 		    val > BSTP_MAX_FORWARD_DELAY) {
2181 			err = EINVAL;
2182 			break;
2183 		}
2184 		bs->bs_bridge_fdelay = val;
2185 		r = 1;
2186 		break;
2187 	case SIOCBRDGSTXHC:
2188 		val = ifbp->ifbrp_txhc;
2189 
2190 		if (val < BSTP_MIN_HOLD_COUNT || val > BSTP_MAX_HOLD_COUNT) {
2191 			err = EINVAL;
2192 			break;
2193 		}
2194 		bs->bs_txholdcount = val;
2195 		LIST_FOREACH(bp, &bs->bs_bplist, bp_next)
2196 			bp->bp_txcount = 0;
2197 		break;
2198 	case SIOCBRDGSIFPRIO:
2199 		val = ifbr->ifbr_priority;
2200 		if (val < 0 || val > BSTP_MAX_PORT_PRIORITY)
2201 			return (EINVAL);
2202 
2203 		/* Limit to steps of 16 */
2204 		val -= val % 16;
2205 		bp->bp_priority = val;
2206 		r = 1;
2207 		break;
2208 	case SIOCBRDGSIFCOST:
2209 		val = ifbr->ifbr_path_cost;
2210 		if (val > BSTP_MAX_PATH_COST) {
2211 			err = EINVAL;
2212 			break;
2213 		}
2214 		if (val == 0) {	/* use auto */
2215 			bp->bp_flags &= ~BSTP_PORT_ADMCOST;
2216 			bp->bp_path_cost = bstp_calc_path_cost(bp);
2217 		} else {
2218 			bp->bp_path_cost = val;
2219 			bp->bp_flags |= BSTP_PORT_ADMCOST;
2220 		}
2221 		r = 1;
2222 		break;
2223 	case SIOCBRDGSPROTO:
2224 		val = ifbp->ifbrp_proto;
2225 
2226 		/* Supported protocol versions */
2227 		switch (val) {
2228 		case BSTP_PROTO_STP:
2229 		case BSTP_PROTO_RSTP:
2230 			bs->bs_protover = val;
2231 			bs->bs_bridge_htime = BSTP_DEFAULT_HELLO_TIME;
2232 			LIST_FOREACH(bp, &bs->bs_bplist, bp_next) {
2233 				/* reinit state */
2234 				bp->bp_infois = BSTP_INFO_DISABLED;
2235 				bp->bp_txcount = 0;
2236 				bstp_set_port_proto(bp, bs->bs_protover);
2237 				bstp_set_port_role(bp, BSTP_ROLE_DISABLED);
2238 				bstp_set_port_tc(bp, BSTP_TCSTATE_INACTIVE);
2239 				bstp_timer_stop(&bp->bp_recent_backup_timer);
2240 			}
2241 			r = 1;
2242 			break;
2243 		default:
2244 			err = EINVAL;
2245 		}
2246 		break;
2247 	default:
2248 		break;
2249 	}
2250 
2251 	if (r)
2252 		bstp_initialization(bs);
2253 
2254 	return (err);
2255 }
2256