kernel - Major bridging functionality added (bug fixes 2)
[dragonfly.git] / sys / net / bridge / bridgestp.c
1 /*
2  * Copyright (c) 2000 Jason L. Wright (jason@thought.net)
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *      This product includes software developed by Jason L. Wright
16  * 4. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
21  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
22  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
23  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
28  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  *
31  * $OpenBSD: bridgestp.c,v 1.5 2001/03/22 03:48:29 jason Exp $
32  * $NetBSD: bridgestp.c,v 1.5 2003/11/28 08:56:48 keihan Exp $
33  * $FreeBSD: src/sys/net/bridgestp.c,v 1.7 2005/10/11 02:58:32 thompsa Exp $
34  */
35
36 /*
37  * Implementation of the spanning tree protocol as defined in
38  * ISO/IEC Final DIS 15802-3 (IEEE P802.1D/D17), May 25, 1998.
39  * (In English: IEEE 802.1D, Draft 17, 1998)
40  */
41
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/mbuf.h>
45 #include <sys/socket.h>
46 #include <sys/sockio.h>
47 #include <sys/kernel.h>
48 #include <sys/callout.h>
49 #include <sys/proc.h>
50 #include <sys/lock.h>
51 #include <sys/thread.h>
52 #include <sys/thread2.h>
53 #include <sys/msgport2.h>
54
55 #include <net/if.h>
56 #include <net/if_dl.h>
57 #include <net/if_types.h>
58 #include <net/if_llc.h>
59 #include <net/if_media.h>
60
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/in_var.h>
64 #include <netinet/if_ether.h>
65 #include <net/bridge/if_bridgevar.h>
66
67 /* BPDU message types */
68 #define BSTP_MSGTYPE_CFG        0x00            /* Configuration */
69 #define BSTP_MSGTYPE_TCN        0x80            /* Topology chg notification */
70
71 /* BPDU flags */
72 #define BSTP_FLAG_TC            0x01            /* Topology change */
73 #define BSTP_FLAG_TCA           0x80            /* Topology change ack */
74
75 #define BSTP_MESSAGE_AGE_INCR   (1 * 256)       /* in 256ths of a second */
76 #define BSTP_TICK_VAL           (1 * 256)       /* in 256ths of a second */
77
78 /*
79  * Because BPDU's do not make nicely aligned structures, two different
80  * declarations are used: bstp_?bpdu (wire representation, packed) and
81  * bstp_*_unit (internal, nicely aligned version).
82  */
83
84 /* configuration bridge protocol data unit */
85 struct bstp_cbpdu {
86         uint8_t         cbu_dsap;               /* LLC: destination sap */
87         uint8_t         cbu_ssap;               /* LLC: source sap */
88         uint8_t         cbu_ctl;                /* LLC: control */
89         uint16_t        cbu_protoid;            /* protocol id */
90         uint8_t         cbu_protover;           /* protocol version */
91         uint8_t         cbu_bpdutype;           /* message type */
92         uint8_t         cbu_flags;              /* flags (below) */
93
94         /* root id */
95         uint16_t        cbu_rootpri;            /* root priority */
96         uint8_t cbu_rootaddr[6];        /* root address */
97
98         uint32_t        cbu_rootpathcost;       /* root path cost */
99
100         /* bridge id */
101         uint16_t        cbu_bridgepri;          /* bridge priority */
102         uint8_t         cbu_bridgeaddr[6];      /* bridge address */
103
104         uint16_t        cbu_portid;             /* port id */
105         uint16_t        cbu_messageage;         /* current message age */
106         uint16_t        cbu_maxage;             /* maximum age */
107         uint16_t        cbu_hellotime;          /* hello time */
108         uint16_t        cbu_forwarddelay;       /* forwarding delay */
109 } __attribute__((__packed__));
110
111 /* topology change notification bridge protocol data unit */
112 struct bstp_tbpdu {
113         uint8_t         tbu_dsap;               /* LLC: destination sap */
114         uint8_t         tbu_ssap;               /* LLC: source sap */
115         uint8_t         tbu_ctl;                /* LLC: control */
116         uint16_t        tbu_protoid;            /* protocol id */
117         uint8_t         tbu_protover;           /* protocol version */
118         uint8_t         tbu_bpdutype;           /* message type */
119 } __attribute__((__packed__));
120
121 const uint8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 };
122
123 static void     bstp_initialize_port(struct bridge_softc *,
124                     struct bridge_iflist *);
125 static void     bstp_ifupdstatus(struct bridge_softc *, struct bridge_iflist *);
126 static void     bstp_enable_port(struct bridge_softc *, struct bridge_iflist *);
127 static void     bstp_disable_port(struct bridge_softc *,
128                     struct bridge_iflist *);
129 #ifdef notused
130 static void     bstp_enable_change_detection(struct bridge_iflist *);
131 static void     bstp_disable_change_detection(struct bridge_iflist *);
132 #endif /* notused */
133 static int      bstp_root_bridge(struct bridge_softc *sc);
134 static void     bstp_transmit_config(struct bridge_softc *,
135                     struct bridge_iflist *);
136 static void     bstp_transmit_tcn(struct bridge_softc *);
137 static void     bstp_received_config_bpdu(struct bridge_softc *,
138                     struct bridge_iflist *, struct bstp_config_unit *);
139 static void     bstp_received_tcn_bpdu(struct bridge_softc *,
140                     struct bridge_iflist *, struct bstp_tcn_unit *);
141 static void     bstp_record_config_information(struct bridge_softc *,
142                     struct bridge_iflist *, struct bstp_config_unit *);
143 static void     bstp_record_config_timeout_values(struct bridge_softc *,
144                     struct bstp_config_unit *);
145 static void     bstp_config_bpdu_generation(struct bridge_softc *);
146 static void     bstp_send_config_bpdu(struct bridge_softc *,
147                     struct bridge_iflist *, struct bstp_config_unit *);
148 static void     bstp_configuration_update(struct bridge_softc *);
149 static void     bstp_port_state_selection(struct bridge_softc *);
150 static void     bstp_clear_peer_info(struct bridge_softc *,
151                     struct bridge_iflist *);
152 static void     bstp_make_forwarding(struct bridge_softc *,
153                     struct bridge_iflist *);
154 static void     bstp_make_blocking(struct bridge_softc *,
155                     struct bridge_iflist *);
156 static void     bstp_make_l1blocking(struct bridge_softc *sc,
157                     struct bridge_iflist *bif);
158 static void     bstp_adjust_bonded_states(struct bridge_softc *sc,
159                     struct bridge_iflist *obif);
160 static void     bstp_set_port_state(struct bridge_iflist *, uint8_t);
161 #ifdef notused
162 static void     bstp_set_bridge_priority(struct bridge_softc *, uint64_t);
163 static void     bstp_set_port_priority(struct bridge_softc *,
164                     struct bridge_iflist *, uint16_t);
165 static void     bstp_set_path_cost(struct bridge_softc *,
166                     struct bridge_iflist *, uint32_t);
167 #endif /* notused */
168 static void     bstp_topology_change_detection(struct bridge_softc *);
169 static void     bstp_topology_change_acknowledged(struct bridge_softc *);
170 static void     bstp_acknowledge_topology_change(struct bridge_softc *,
171                     struct bridge_iflist *);
172
173 static void     bstp_tick(void *);
174 static void     bstp_timer_start(struct bridge_timer *, uint16_t);
175 static void     bstp_timer_stop(struct bridge_timer *);
176 static int      bstp_timer_expired(struct bridge_timer *, uint16_t);
177
178 static void     bstp_hold_timer_expiry(struct bridge_softc *,
179                     struct bridge_iflist *);
180 static void     bstp_message_age_timer_expiry(struct bridge_softc *,
181                     struct bridge_iflist *);
182 static void     bstp_forward_delay_timer_expiry(struct bridge_softc *,
183                     struct bridge_iflist *);
184 static void     bstp_topology_change_timer_expiry(struct bridge_softc *);
185 static void     bstp_tcn_timer_expiry(struct bridge_softc *);
186 static void     bstp_hello_timer_expiry(struct bridge_softc *);
187 static int      bstp_addr_cmp(const uint8_t *, const uint8_t *);
188
189 /*
190  * When transmitting a config we tack on our path cost to
191  * our aggregated path-to-root cost.
192  */
193 static void
194 bstp_transmit_config(struct bridge_softc *sc, struct bridge_iflist *bif)
195 {
196         if (bif->bif_hold_timer.active) {
197                 bif->bif_config_pending = 1;
198                 return;
199         }
200
201         bif->bif_config_bpdu.cu_message_type = BSTP_MSGTYPE_CFG;
202         bif->bif_config_bpdu.cu_rootid = sc->sc_designated_root;
203         bif->bif_config_bpdu.cu_root_path_cost = sc->sc_designated_cost +
204                                                  bif->bif_path_cost;
205         bif->bif_config_bpdu.cu_bridge_id = sc->sc_bridge_id;
206         bif->bif_config_bpdu.cu_port_id = bif->bif_port_id;
207
208         if (bstp_root_bridge(sc)) {
209                 bif->bif_config_bpdu.cu_message_age = 0;
210         } else if (sc->sc_root_port) {
211                 bif->bif_config_bpdu.cu_message_age =
212                         sc->sc_root_port->bif_message_age_timer.value +
213                         BSTP_MESSAGE_AGE_INCR;
214         } else {
215                 bif->bif_config_bpdu.cu_message_age = BSTP_MESSAGE_AGE_INCR;
216         }
217
218         bif->bif_config_bpdu.cu_max_age = sc->sc_max_age;
219         bif->bif_config_bpdu.cu_hello_time = sc->sc_hello_time;
220         bif->bif_config_bpdu.cu_forward_delay = sc->sc_forward_delay;
221         bif->bif_config_bpdu.cu_topology_change_acknowledgment
222             = bif->bif_topology_change_acknowledge;
223         bif->bif_config_bpdu.cu_topology_change = sc->sc_topology_change;
224
225         if (bif->bif_config_bpdu.cu_message_age < sc->sc_max_age ||
226             (sc->sc_ifp->if_flags & IFF_LINK1)) {
227                 bif->bif_topology_change_acknowledge = 0;
228                 bif->bif_config_pending = 0;
229                 bstp_send_config_bpdu(sc, bif, &bif->bif_config_bpdu);
230                 bstp_timer_start(&bif->bif_hold_timer, 0);
231         }
232 }
233
234 static void
235 bstp_send_config_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif,
236                       struct bstp_config_unit *cu)
237 {
238         struct ifnet *ifp;
239         struct mbuf *m;
240         struct ether_header *eh;
241         struct bstp_cbpdu bpdu;
242
243         ifp = bif->bif_ifp;
244
245         if ((ifp->if_flags & IFF_RUNNING) == 0)
246                 return;
247
248         MGETHDR(m, MB_DONTWAIT, MT_DATA);
249         if (m == NULL)
250                 return;
251
252         eh = mtod(m, struct ether_header *);
253
254         m->m_pkthdr.rcvif = ifp;
255         m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
256         m->m_len = m->m_pkthdr.len;
257
258         bpdu.cbu_ssap = bpdu.cbu_dsap = LLC_8021D_LSAP;
259         bpdu.cbu_ctl = LLC_UI;
260         bpdu.cbu_protoid = htons(0);
261         bpdu.cbu_protover = 0;
262         bpdu.cbu_bpdutype = cu->cu_message_type;
263         bpdu.cbu_flags = (cu->cu_topology_change ? BSTP_FLAG_TC : 0) |
264             (cu->cu_topology_change_acknowledgment ? BSTP_FLAG_TCA : 0);
265
266         bpdu.cbu_rootpri = htons(cu->cu_rootid >> 48);
267         bpdu.cbu_rootaddr[0] = cu->cu_rootid >> 40;
268         bpdu.cbu_rootaddr[1] = cu->cu_rootid >> 32;
269         bpdu.cbu_rootaddr[2] = cu->cu_rootid >> 24;
270         bpdu.cbu_rootaddr[3] = cu->cu_rootid >> 16;
271         bpdu.cbu_rootaddr[4] = cu->cu_rootid >> 8;
272         bpdu.cbu_rootaddr[5] = cu->cu_rootid >> 0;
273
274         bpdu.cbu_rootpathcost = htonl(cu->cu_root_path_cost);
275
276         bpdu.cbu_bridgepri = htons(cu->cu_bridge_id >> 48);
277         bpdu.cbu_bridgeaddr[0] = cu->cu_bridge_id >> 40;
278         bpdu.cbu_bridgeaddr[1] = cu->cu_bridge_id >> 32;
279         bpdu.cbu_bridgeaddr[2] = cu->cu_bridge_id >> 24;
280         bpdu.cbu_bridgeaddr[3] = cu->cu_bridge_id >> 16;
281         bpdu.cbu_bridgeaddr[4] = cu->cu_bridge_id >> 8;
282         bpdu.cbu_bridgeaddr[5] = cu->cu_bridge_id >> 0;
283
284         bpdu.cbu_portid = htons(cu->cu_port_id);
285         bpdu.cbu_messageage = htons(cu->cu_message_age);
286         bpdu.cbu_maxage = htons(cu->cu_max_age);
287         bpdu.cbu_hellotime = htons(cu->cu_hello_time);
288         bpdu.cbu_forwarddelay = htons(cu->cu_forward_delay);
289
290         /*
291          * Packets sent from the bridge always use the bridge MAC
292          * as the source.
293          */
294         memcpy(eh->ether_shost, IF_LLADDR(sc->sc_ifp), ETHER_ADDR_LEN);
295         memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
296         eh->ether_type = htons(sizeof(bpdu));
297
298         memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu));
299
300         bridge_enqueue(ifp, m);
301 }
302
303 static int
304 bstp_root_bridge(struct bridge_softc *sc)
305 {
306         return (sc->sc_designated_root == sc->sc_bridge_id);
307 }
308
309 /*
310  * Returns TRUE if the recorded information from our peer has a shorter
311  * graph distance than our current best.
312  */
313 int
314 bstp_supersedes_port_info(struct bridge_softc *sc, struct bridge_iflist *bif)
315 {
316         if (bif->bif_peer_root < sc->sc_designated_root)
317                 return (1);
318         if (bif->bif_peer_root > sc->sc_designated_root)
319                 return (0);
320
321         /*
322          * Both bif_peer_cost and sc_designated_cost have NOT added in
323          * bif->bif_path_cost, so we can optimize it out.
324          */
325         if (bif->bif_peer_cost < sc->sc_designated_cost)
326                 return (1);
327         if (bif->bif_peer_cost > sc->sc_designated_cost)
328                 return (0);
329
330         if (bif->bif_peer_bridge < sc->sc_designated_bridge)
331                 return (1);
332         if (bif->bif_peer_bridge > sc->sc_designated_bridge)
333                 return (0);
334
335         /* bridge_id or bridge+port collision w/peer returns TRUE */
336         if (bif->bif_peer_bridge != sc->sc_bridge_id)
337                 return (1);
338         if (bif->bif_peer_port <= sc->sc_designated_port)
339                 return (1);
340         return (0);
341 }
342
343 /*
344  * The shorter graph distance represented by cu (most of which is also
345  * already stored in our bif_peer_* fields) becomes the designated info.
346  *
347  * NOTE: sc_designated_cost does not include bif_path_cost, it is added
348  *       in later on a port-by-port basis as needed.
349  */
350 static void
351 bstp_record_config_information(struct bridge_softc *sc,
352                                struct bridge_iflist *bif,
353                                struct bstp_config_unit *cu)
354 {
355         sc->sc_designated_root = bif->bif_peer_root;
356         sc->sc_designated_cost = bif->bif_peer_cost;
357         sc->sc_designated_bridge = bif->bif_peer_bridge;
358         sc->sc_designated_port = bif->bif_peer_port;
359         bstp_timer_start(&bif->bif_message_age_timer, cu->cu_message_age);
360 }
361
362 static void
363 bstp_record_config_timeout_values(struct bridge_softc *sc,
364                                   struct bstp_config_unit *config)
365 {
366         sc->sc_max_age = config->cu_max_age;
367         sc->sc_hello_time = config->cu_hello_time;
368         sc->sc_forward_delay = config->cu_forward_delay;
369         sc->sc_topology_change = config->cu_topology_change;
370 }
371
372 static void
373 bstp_config_bpdu_generation(struct bridge_softc *sc)
374 {
375         struct bridge_iflist *bif, *nbif;
376
377         TAILQ_FOREACH_MUTABLE(bif, &sc->sc_iflists[mycpuid], bif_next, nbif) {
378                 if ((bif->bif_flags & IFBIF_STP) == 0)
379                         continue;
380                 if (bif->bif_state != BSTP_IFSTATE_DISABLED &&
381                     ((sc->sc_ifp->if_flags & IFF_LINK1) ||
382                      (bif->bif_flags & IFBIF_DESIGNATED))) {
383                         bstp_transmit_config(sc, bif);
384                 }
385
386                 if (nbif != NULL && !nbif->bif_onlist) {
387                         KKASSERT(bif->bif_onlist);
388                         nbif = TAILQ_NEXT(bif, bif_next);
389                 }
390         }
391 }
392
393 static void
394 bstp_transmit_tcn(struct bridge_softc *sc)
395 {
396         struct bstp_tbpdu bpdu;
397         struct ifnet *ifp;
398         struct ether_header *eh;
399         struct mbuf *m;
400
401         if (sc->sc_root_port == NULL)   /* all iterfaces disabled */
402                 return;
403
404         ifp = sc->sc_root_port->bif_ifp;
405         if ((ifp->if_flags & IFF_RUNNING) == 0)
406                 return;
407
408         MGETHDR(m, MB_DONTWAIT, MT_DATA);
409         if (m == NULL)
410                 return;
411
412         m->m_pkthdr.rcvif = ifp;
413         m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu);
414         m->m_len = m->m_pkthdr.len;
415
416         eh = mtod(m, struct ether_header *);
417
418         /*
419          * Packets sent from the bridge always use the bridge MAC
420          * as the source.
421          */
422         memcpy(eh->ether_shost, IF_LLADDR(sc->sc_ifp), ETHER_ADDR_LEN);
423         memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN);
424         eh->ether_type = htons(sizeof(bpdu));
425
426         bpdu.tbu_ssap = bpdu.tbu_dsap = LLC_8021D_LSAP;
427         bpdu.tbu_ctl = LLC_UI;
428         bpdu.tbu_protoid = 0;
429         bpdu.tbu_protover = 0;
430         bpdu.tbu_bpdutype = BSTP_MSGTYPE_TCN;
431
432         memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu));
433
434         bridge_enqueue(ifp, m);
435 }
436
437 /*
438  * Recalculate sc->sc_designated* and sc->sc_root_port (if our bridge
439  * is calculated to be the root bridge).  We do this by initializing
440  * the designated variables to point at us and then scan our peers.
441  * Any uninitialized peers will have a max-value root.
442  *
443  * Clear IFBIF_DESIGNATED on any ports which no longer match the criteria
444  * required to be a designated port.  Only aged out ports and the root
445  * port can be designated.
446  *
447  * If we win we do a second scan to determine which port on our bridge
448  * is the best.
449  */
450 static void
451 bstp_configuration_update(struct bridge_softc *sc)
452 {
453         uint64_t        designated_root = sc->sc_bridge_id;
454         uint64_t        designated_bridge = sc->sc_bridge_id;
455         uint32_t        designated_cost = 0xFFFFFFFFU;
456         uint32_t        designated_root_cost = 0xFFFFFFFFU;
457         uint16_t        designated_port = 65535;
458         struct bridge_iflist *root_port = NULL;
459         struct bridge_iflist *bif;
460
461         /*
462          * Resolve information from our peers.  Aged peers will have
463          * a maxed bif_peer_root and not come under consideration.
464          */
465         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
466                 if ((bif->bif_flags & IFBIF_STP) == 0)
467                         continue;
468                 if (bif->bif_state == BSTP_IFSTATE_DISABLED ||
469                     bif->bif_state == BSTP_IFSTATE_L1BLOCKING) {
470                         continue;
471                 }
472
473                 if (bif->bif_peer_root > designated_root)
474                         continue;
475                 if (bif->bif_peer_root < designated_root)
476                         goto set_port;
477
478                 /*
479                  * NOTE: The designated_cost temporary variable already added
480                  *       in the path code of the related root port.
481                  */
482                 if (bif->bif_peer_cost + bif->bif_path_cost > designated_cost)
483                         continue;
484                 if (bif->bif_peer_cost + bif->bif_path_cost < designated_cost)
485                         goto set_port;
486
487                 if (bif->bif_peer_bridge > designated_bridge)
488                         continue;
489                 if (bif->bif_peer_bridge < designated_bridge)
490                         goto set_port;
491
492                 if (bif->bif_peer_port > designated_port)
493                         continue;
494                 if (bif->bif_peer_port < designated_port)
495                         goto set_port;
496
497                 /*
498                  * Same root, path cost, bridge, and port.  Set the root
499                  * only if we do not already have it.
500                  */
501                 if (root_port)
502                         continue;
503
504                 /*
505                  * New root port (from peers)
506                  *
507                  * NOTE: Temporarily add bif_path_cost into the designated
508                  *       cost to reduce complexity in the loop, it will be
509                  *       subtracted out when we are done.
510                  */
511 set_port:
512                 designated_root = bif->bif_peer_root;
513                 designated_cost = bif->bif_peer_cost + bif->bif_path_cost;
514                 designated_root_cost = bif->bif_peer_cost;
515                 designated_bridge = bif->bif_peer_bridge;
516                 designated_port = bif->bif_peer_port;
517                 root_port = bif;
518         }
519
520         /*
521          * root_port will be NULL at the start here if all of our
522          * peers are aged or are not as good a root as our bridge would
523          * be.  It can also be NULL due to all related links being
524          * disabled.
525          *
526          * If the root winds up being our bridge scan again against local
527          * information.  Unconditionally update IFBIF_DESIGNATED.
528          */
529         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
530                 bif->bif_flags &= ~(IFBIF_DESIGNATED | IFBIF_ROOT);
531                 if ((bif->bif_flags & IFBIF_STP) == 0)
532                         continue;
533                 if (bif->bif_state == BSTP_IFSTATE_DISABLED ||
534                     bif->bif_state == BSTP_IFSTATE_L1BLOCKING) {
535                         continue;
536                 }
537
538                 /*
539                  * Set DESIGNATED for an aged or unknown peer.
540                  */
541                 if (bif->bif_peer_bridge == 0xFFFFFFFFFFFFFFFFLLU)
542                         bif->bif_flags |= IFBIF_DESIGNATED;
543                 if (designated_root != sc->sc_bridge_id)
544                         continue;
545
546                 /*
547                  * This is only reached if our bridge is the root bridge,
548                  * select the root port (IFBIF_DESIGNATED is set at the
549                  * end).
550                  *
551                  * Since we are the root the peer cost should already include
552                  * our path cost.  We still need the combined costs from both
553                  * our point of view and the peer's point of view to match
554                  * up with the peer.
555                  *
556                  * If we used ONLY our path cost here we would have no peer
557                  * path cost in the calculation and would reach a different
558                  * conclusion than our peer has reached.
559                  */
560                 if (bif->bif_peer_cost > designated_cost)
561                         continue;
562                 if (bif->bif_peer_cost < designated_cost)
563                         goto set_port2;
564
565                 if (bif->bif_port_id > designated_port)
566                         continue;
567                 if (bif->bif_port_id < designated_port)
568                         goto set_port2;
569                 /* degenerate case (possible peer collision w/our key */
570
571                 /*
572                  * New port.  Since we are the root, the root cost is always
573                  * 0.  Since we are the root the peer path should be our
574                  * path cost + peer path cost.
575                  */
576 set_port2:
577                 designated_cost = bif->bif_peer_cost;
578                 designated_root_cost = 0;
579                 designated_bridge = sc->sc_bridge_id;
580                 designated_port = bif->bif_port_id;
581                 root_port = bif;
582         }
583
584         /*
585          * Update aggregate information.  The selected root port always
586          * becomes a designated port (along with aged ports).  This can
587          * either be the port whos peer is closest to the root or it
588          * can be one of our ports if our bridge is the root.
589          *
590          * The root cost we record in sc_designated_root does not include
591          * bif_path_cost of the root port, since we may transmit this
592          * out of any port we will add the cost back in later on on
593          * a per-port basis.
594          *
595          * root_port can be NULL here (if all links are disabled)
596          */
597         if (root_port) {
598                 sc->sc_designated_root = designated_root;
599                 sc->sc_designated_cost = designated_root_cost;
600                 sc->sc_designated_bridge = designated_bridge;
601                 sc->sc_designated_port = designated_port;
602                 root_port->bif_flags |= IFBIF_DESIGNATED | IFBIF_ROOT;
603         } else {
604                 sc->sc_designated_root = designated_root;
605                 sc->sc_designated_cost = designated_cost;
606                 sc->sc_designated_bridge = designated_bridge;
607                 sc->sc_designated_port = designated_port;
608         }
609         sc->sc_root_port = root_port;
610 }
611
612 /*
613  * Calculate the desired state for each interface link on our bridge.
614  *
615  * The best port will match against sc->sc_root_port (whether we are root
616  * or whether that port is the closest to the root).  We push this port
617  * towards a FORWARDING state.
618  *
619  * Next come designated ports, either aged ports or ports with no peer info
620  * (yet), or the peer who is closest to the root. We push this port towards
621  * a FORWARDING state as well.
622  *
623  * Any remaining ports are pushed towards a BLOCKING state.  Both sides of
624  * the port (us and our peer) should wind up placing the two ends in this
625  * state or bad things happen.
626  */
627 static void
628 bstp_port_state_selection(struct bridge_softc *sc)
629 {
630         struct bridge_iflist *bif, *nbif;
631
632         TAILQ_FOREACH_MUTABLE(bif, &sc->sc_iflists[mycpuid], bif_next, nbif) {
633                 if ((bif->bif_flags & IFBIF_STP) == 0)
634                         continue;
635                 if (sc->sc_root_port &&
636                     bif->bif_info == sc->sc_root_port->bif_info) {
637                         bif->bif_config_pending = 0;
638                         bif->bif_topology_change_acknowledge = 0;
639                         bstp_make_forwarding(sc, bif);
640                 } else if (bif->bif_flags & IFBIF_DESIGNATED) {
641                         bstp_timer_stop(&bif->bif_message_age_timer);
642                         bstp_make_forwarding(sc, bif);
643                 } else {
644                         bif->bif_config_pending = 0;
645                         bif->bif_topology_change_acknowledge = 0;
646                         bstp_make_blocking(sc, bif);
647                 }
648
649                 if (nbif != NULL && !nbif->bif_onlist) {
650                         KKASSERT(bif->bif_onlist);
651                         nbif = TAILQ_NEXT(bif, bif_next);
652                 }
653         }
654 }
655
656 /*
657  * Clear peer info, effectively makes the port looked aged out.
658  * It becomes a designated go-to port.
659  */
660 static void
661 bstp_clear_peer_info(struct bridge_softc *sc, struct bridge_iflist *bif)
662 {
663         bif->bif_peer_root = 0xFFFFFFFFFFFFFFFFLLU;
664         bif->bif_peer_cost = 0xFFFFFFFFU;
665         bif->bif_peer_bridge = 0xFFFFFFFFFFFFFFFFLLU;
666         bif->bif_peer_port = 0xFFFFU;
667
668         if (bif->bif_state != BSTP_IFSTATE_DISABLED &&
669             bif->bif_state != BSTP_IFSTATE_L1BLOCKING) {
670                 bif->bif_flags |= IFBIF_DESIGNATED;
671         }
672 }
673
674 static void
675 bstp_make_forwarding(struct bridge_softc *sc, struct bridge_iflist *bif)
676 {
677         if (bif->bif_state == BSTP_IFSTATE_BLOCKING ||
678             bif->bif_state == BSTP_IFSTATE_BONDED) {
679                 bstp_set_port_state(bif, BSTP_IFSTATE_LISTENING);
680                 bstp_timer_start(&bif->bif_forward_delay_timer, 0);
681         }
682 }
683
684 static void
685 bstp_make_blocking(struct bridge_softc *sc, struct bridge_iflist *bif)
686 {
687         if (bif->bif_state != BSTP_IFSTATE_DISABLED &&
688             bif->bif_state != BSTP_IFSTATE_BLOCKING &&
689             bif->bif_state != BSTP_IFSTATE_BONDED &&
690             bif->bif_state != BSTP_IFSTATE_L1BLOCKING) {
691                 if ((bif->bif_state == BSTP_IFSTATE_FORWARDING) ||
692                     (bif->bif_state == BSTP_IFSTATE_LEARNING)) {
693                         if (bif->bif_change_detection_enabled) {
694                                 bstp_topology_change_detection(sc);
695                         }
696                 }
697                 bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING);
698                 bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN);
699                 bstp_timer_stop(&bif->bif_forward_delay_timer);
700                 if (sc->sc_ifp->if_flags & IFF_LINK2)
701                         bstp_adjust_bonded_states(sc, bif);
702         }
703 }
704
705 static void
706 bstp_make_l1blocking(struct bridge_softc *sc, struct bridge_iflist *bif)
707 {
708         int was_forwarding = (bif->bif_state == BSTP_IFSTATE_FORWARDING);
709
710         switch(bif->bif_state) {
711         case BSTP_IFSTATE_LISTENING:
712         case BSTP_IFSTATE_LEARNING:
713         case BSTP_IFSTATE_FORWARDING:
714         case BSTP_IFSTATE_BLOCKING:
715         case BSTP_IFSTATE_BONDED:
716                 bstp_set_port_state(bif, BSTP_IFSTATE_L1BLOCKING);
717                 bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN);
718                 bstp_timer_stop(&bif->bif_forward_delay_timer);
719                 bstp_timer_stop(&bif->bif_link1_timer);
720                 if (bif->bif_flags & IFBIF_DESIGNATED) {
721                         bif->bif_flags &= ~IFBIF_DESIGNATED;
722                         bstp_configuration_update(sc);
723                         bstp_port_state_selection(sc);
724                 }
725                 if (was_forwarding && (sc->sc_ifp->if_flags & IFF_LINK2))
726                         bstp_adjust_bonded_states(sc, bif);
727                 break;
728         default:
729                 break;
730         }
731 }
732
733 /*
734  * Member (bif) changes to or from a FORWARDING state.  All members in the
735  * same bonding group which are in a BLOCKING or BONDED state must be set
736  * to either BLOCKING or BONDED based on whether any members in the bonding
737  * group remain in the FORWARDING state.
738  *
739  * Going between the BLOCKING and BONDED states does not require a
740  * configuration update.
741  */
742 static void
743 bstp_adjust_bonded_states(struct bridge_softc *sc, struct bridge_iflist *obif)
744 {
745         struct bridge_iflist *bif;
746         int state = BSTP_IFSTATE_BLOCKING;
747
748         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
749                 if ((bif->bif_flags & IFBIF_STP) == 0)
750                         continue;
751                 if (bif->bif_state != BSTP_IFSTATE_FORWARDING)
752                         continue;
753                 if (memcmp(IF_LLADDR(bif->bif_ifp), IF_LLADDR(obif->bif_ifp),
754                            ETHER_ADDR_LEN) != 0) {
755                         continue;
756                 }
757                 state = BSTP_IFSTATE_BONDED;
758                 break;
759         }
760         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
761                 if ((bif->bif_flags & IFBIF_STP) == 0)
762                         continue;
763                 if (bif->bif_state != BSTP_IFSTATE_BLOCKING &&
764                     bif->bif_state != BSTP_IFSTATE_BONDED) {
765                         continue;
766                 }
767                 if (memcmp(IF_LLADDR(bif->bif_ifp), IF_LLADDR(obif->bif_ifp),
768                            ETHER_ADDR_LEN) != 0) {
769                         continue;
770                 }
771                 if (bif->bif_bond_weight == 0)
772                         bif->bif_state = BSTP_IFSTATE_BLOCKING;
773                 else
774                         bif->bif_state = state;
775         }
776 }
777
778 static void
779 bstp_set_port_state(struct bridge_iflist *bif, uint8_t state)
780 {
781         bif->bif_state = state;
782 }
783
784 static void
785 bstp_topology_change_detection(struct bridge_softc *sc)
786 {
787         if (bstp_root_bridge(sc)) {
788                 sc->sc_topology_change = 1;
789                 bstp_timer_start(&sc->sc_topology_change_timer, 0);
790         } else if (!sc->sc_topology_change_detected) {
791                 bstp_transmit_tcn(sc);
792                 bstp_timer_start(&sc->sc_tcn_timer, 0);
793         }
794         sc->sc_topology_change_detected = 1;
795 }
796
797 static void
798 bstp_topology_change_acknowledged(struct bridge_softc *sc)
799 {
800         sc->sc_topology_change_detected = 0;
801         bstp_timer_stop(&sc->sc_tcn_timer);
802 }
803
804 static void
805 bstp_acknowledge_topology_change(struct bridge_softc *sc,
806                                  struct bridge_iflist *bif)
807 {
808         bif->bif_topology_change_acknowledge = 1;
809         bstp_transmit_config(sc, bif);
810 }
811
812 void
813 bstp_input(struct bridge_softc *sc, struct bridge_iflist *bif, struct mbuf *m)
814 {
815         struct ether_header *eh;
816         struct bstp_tbpdu tpdu;
817         struct bstp_cbpdu cpdu;
818         struct bstp_config_unit cu;
819         struct bstp_tcn_unit tu;
820         uint16_t len;
821
822         if ((bif->bif_flags & IFBIF_STP) == 0)
823                 goto out;
824
825         /*
826          * The L1BLOCKING (ping pong failover) test needs to reset the
827          * timer if LINK1 is active.
828          */
829         if (bif->bif_state == BSTP_IFSTATE_L1BLOCKING) {
830                 bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING);
831                 if (sc->sc_ifp->if_flags & IFF_LINK1)
832                         bstp_timer_start(&bif->bif_link1_timer, 0);
833                 bstp_make_forwarding(sc, bif);
834         } else if (sc->sc_ifp->if_flags & IFF_LINK1) {
835                 bstp_timer_start(&bif->bif_link1_timer, 0);
836         }
837
838         eh = mtod(m, struct ether_header *);
839
840         len = ntohs(eh->ether_type);
841         if (len < sizeof(tpdu))
842                 goto out;
843
844         m_adj(m, ETHER_HDR_LEN);
845
846         if (m->m_pkthdr.len > len)
847                 m_adj(m, len - m->m_pkthdr.len);
848         if (m->m_len < sizeof(tpdu) &&
849             (m = m_pullup(m, sizeof(tpdu))) == NULL)
850                 goto out;
851
852         memcpy(&tpdu, mtod(m, caddr_t), sizeof(tpdu));
853
854         if (tpdu.tbu_dsap != LLC_8021D_LSAP ||
855             tpdu.tbu_ssap != LLC_8021D_LSAP ||
856             tpdu.tbu_ctl != LLC_UI)
857                 goto out;
858         if (tpdu.tbu_protoid != 0 || tpdu.tbu_protover != 0)
859                 goto out;
860
861         switch (tpdu.tbu_bpdutype) {
862         case BSTP_MSGTYPE_TCN:
863                 tu.tu_message_type = tpdu.tbu_bpdutype;
864                 bstp_received_tcn_bpdu(sc, bif, &tu);
865                 break;
866         case BSTP_MSGTYPE_CFG:
867                 if (m->m_len < sizeof(cpdu) &&
868                     (m = m_pullup(m, sizeof(cpdu))) == NULL)
869                         goto out;
870                 memcpy(&cpdu, mtod(m, caddr_t), sizeof(cpdu));
871
872                 cu.cu_rootid =
873                     (((uint64_t)ntohs(cpdu.cbu_rootpri)) << 48) |
874                     (((uint64_t)cpdu.cbu_rootaddr[0]) << 40) |
875                     (((uint64_t)cpdu.cbu_rootaddr[1]) << 32) |
876                     (((uint64_t)cpdu.cbu_rootaddr[2]) << 24) |
877                     (((uint64_t)cpdu.cbu_rootaddr[3]) << 16) |
878                     (((uint64_t)cpdu.cbu_rootaddr[4]) << 8) |
879                     (((uint64_t)cpdu.cbu_rootaddr[5]) << 0);
880
881                 cu.cu_bridge_id =
882                     (((uint64_t)ntohs(cpdu.cbu_bridgepri)) << 48) |
883                     (((uint64_t)cpdu.cbu_bridgeaddr[0]) << 40) |
884                     (((uint64_t)cpdu.cbu_bridgeaddr[1]) << 32) |
885                     (((uint64_t)cpdu.cbu_bridgeaddr[2]) << 24) |
886                     (((uint64_t)cpdu.cbu_bridgeaddr[3]) << 16) |
887                     (((uint64_t)cpdu.cbu_bridgeaddr[4]) << 8) |
888                     (((uint64_t)cpdu.cbu_bridgeaddr[5]) << 0);
889
890                 cu.cu_root_path_cost = ntohl(cpdu.cbu_rootpathcost);
891                 cu.cu_message_age = ntohs(cpdu.cbu_messageage);
892                 cu.cu_max_age = ntohs(cpdu.cbu_maxage);
893                 cu.cu_hello_time = ntohs(cpdu.cbu_hellotime);
894                 cu.cu_forward_delay = ntohs(cpdu.cbu_forwarddelay);
895                 cu.cu_port_id = ntohs(cpdu.cbu_portid);
896                 cu.cu_message_type = cpdu.cbu_bpdutype;
897                 cu.cu_topology_change_acknowledgment =
898                     (cpdu.cbu_flags & BSTP_FLAG_TCA) ? 1 : 0;
899                 cu.cu_topology_change =
900                     (cpdu.cbu_flags & BSTP_FLAG_TC) ? 1 : 0;
901                 bstp_received_config_bpdu(sc, bif, &cu);
902                 break;
903         default:
904                 goto out;
905         }
906 out:
907         if (m)
908                 m_freem(m);
909 }
910
911 static void
912 bstp_received_config_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif,
913                           struct bstp_config_unit *cu)
914 {
915         int iamroot;
916
917         iamroot = bstp_root_bridge(sc);
918
919         if (bif->bif_state != BSTP_IFSTATE_DISABLED) {
920                 /*
921                  * Record information from peer.  The peer_cost field
922                  * does not include the local bif->bif_path_cost, it will
923                  * be added in as needed (since it can be modified manually
924                  * this way we don't have to worry about fixups).
925                  */
926                 bif->bif_peer_root = cu->cu_rootid;
927                 bif->bif_peer_cost = cu->cu_root_path_cost;
928                 bif->bif_peer_bridge = cu->cu_bridge_id;
929                 bif->bif_peer_port = cu->cu_port_id;
930
931                 if (bstp_supersedes_port_info(sc, bif)) {
932                         bstp_record_config_information(sc, bif, cu);
933                         bstp_configuration_update(sc);
934                         bstp_port_state_selection(sc);
935
936                         /*
937                          * If our bridge loses its root status (?)
938                          *
939                          * Hello's (unsolicited CFG packets) are generated
940                          * every hello period of LINK1 is set, otherwise
941                          * we are no longer the root bridge and must stop
942                          * generating unsolicited CFG packets.
943                          */
944                         if (iamroot && bstp_root_bridge(sc) == 0) {
945                                 if ((sc->sc_ifp->if_flags & IFF_LINK1) == 0)
946                                         bstp_timer_stop(&sc->sc_hello_timer);
947
948                                 if (sc->sc_topology_change_detected) {
949                                         bstp_timer_stop(
950                                             &sc->sc_topology_change_timer);
951                                         bstp_transmit_tcn(sc);
952                                         bstp_timer_start(&sc->sc_tcn_timer, 0);
953                                 }
954                         }
955
956                         if (sc->sc_root_port &&
957                             bif->bif_info == sc->sc_root_port->bif_info) {
958                                 bstp_record_config_timeout_values(sc, cu);
959                                 bstp_config_bpdu_generation(sc);
960
961                                 if (cu->cu_topology_change_acknowledgment)
962                                         bstp_topology_change_acknowledged(sc);
963                         }
964                 } else if (bif->bif_flags & IFBIF_DESIGNATED) {
965                         /*
966                          * Update designated ports (aged out peers or
967                          * the port closest to the root) at a faster pace.
968                          *
969                          * Clear our designated flag if we aren't marked
970                          * as the root port.
971                          */
972                         bstp_transmit_config(sc, bif);
973                         if ((bif->bif_flags & IFBIF_ROOT) == 0) {
974                                 bif->bif_flags &= ~IFBIF_DESIGNATED;
975                                 bstp_configuration_update(sc);
976                                 bstp_port_state_selection(sc);
977                         }
978                 }
979         }
980 }
981
982 static void
983 bstp_received_tcn_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif,
984                        struct bstp_tcn_unit *tcn)
985 {
986         if (bif->bif_state != BSTP_IFSTATE_DISABLED &&
987             (bif->bif_flags & IFBIF_DESIGNATED)) {
988                 bstp_topology_change_detection(sc);
989                 bstp_acknowledge_topology_change(sc, bif);
990         }
991 }
992
993 /*
994  * link1 forces continuous hello's (the bridge interface must be cycled
995  * to start them up), so keep the timer hot if that is the case, otherwise
996  * only send HELLO's if we are the root.
997  */
998 static void
999 bstp_hello_timer_expiry(struct bridge_softc *sc)
1000 {
1001         bstp_config_bpdu_generation(sc);
1002
1003         if ((sc->sc_ifp->if_flags & IFF_LINK1) || bstp_root_bridge(sc))
1004                 bstp_timer_start(&sc->sc_hello_timer, 0);
1005 }
1006
1007 static void
1008 bstp_message_age_timer_expiry(struct bridge_softc *sc,
1009                               struct bridge_iflist *bif)
1010 {
1011         int iamroot;
1012
1013         iamroot = bstp_root_bridge(sc);
1014         bstp_clear_peer_info(sc, bif);
1015         bstp_configuration_update(sc);
1016         bstp_port_state_selection(sc);
1017
1018         /*
1019          * If we've become the root and were not the root before
1020          * we have some cleanup to do.  This also occurs if we
1021          * wind up being completely isolated.
1022          */
1023         if (iamroot == 0 && bstp_root_bridge(sc)) {
1024                 sc->sc_max_age = sc->sc_bridge_max_age;
1025                 sc->sc_hello_time = sc->sc_bridge_hello_time;
1026                 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
1027
1028                 bstp_topology_change_detection(sc);
1029                 bstp_timer_stop(&sc->sc_tcn_timer);
1030                 bstp_config_bpdu_generation(sc);
1031                 bstp_timer_start(&sc->sc_hello_timer, 0);
1032         }
1033 }
1034
1035 static void
1036 bstp_forward_delay_timer_expiry(struct bridge_softc *sc,
1037                                 struct bridge_iflist *bif)
1038 {
1039         if (bif->bif_state == BSTP_IFSTATE_LISTENING) {
1040                 bstp_set_port_state(bif, BSTP_IFSTATE_LEARNING);
1041                 bstp_timer_start(&bif->bif_forward_delay_timer, 0);
1042         } else if (bif->bif_state == BSTP_IFSTATE_LEARNING) {
1043                 bstp_set_port_state(bif, BSTP_IFSTATE_FORWARDING);
1044                 if (sc->sc_designated_bridge == sc->sc_bridge_id &&
1045                     bif->bif_change_detection_enabled) {
1046                         bstp_topology_change_detection(sc);
1047                 }
1048                 if (sc->sc_ifp->if_flags & IFF_LINK2)
1049                         bstp_adjust_bonded_states(sc, bif);
1050         }
1051 }
1052
1053 static void
1054 bstp_tcn_timer_expiry(struct bridge_softc *sc)
1055 {
1056         bstp_transmit_tcn(sc);
1057         bstp_timer_start(&sc->sc_tcn_timer, 0);
1058 }
1059
1060 static void
1061 bstp_topology_change_timer_expiry(struct bridge_softc *sc)
1062 {
1063         sc->sc_topology_change_detected = 0;
1064         sc->sc_topology_change = 0;
1065 }
1066
1067 static void
1068 bstp_hold_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif)
1069 {
1070         if (bif->bif_config_pending)
1071                 bstp_transmit_config(sc, bif);
1072 }
1073
1074 /*
1075  * If no traffic received directly on this port for the specified
1076  * period with link1 set we go into a special blocking mode to
1077  * fail-over traffic to another port.
1078  */
1079 static void
1080 bstp_link1_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif)
1081 {
1082         if (sc->sc_ifp->if_flags & IFF_LINK1)
1083                 bstp_make_l1blocking(sc, bif);
1084 }
1085
1086 static int
1087 bstp_addr_cmp(const uint8_t *a, const uint8_t *b)
1088 {
1089         int i, d;
1090
1091         for (i = 0, d = 0; i < ETHER_ADDR_LEN && d == 0; i++) {
1092                 d = ((int)a[i]) - ((int)b[i]);
1093         }
1094
1095         return (d);
1096 }
1097
1098 void
1099 bstp_initialization(struct bridge_softc *sc)
1100 {
1101         struct bridge_iflist *bif, *mif, *nbif;
1102         u_char *e_addr;
1103
1104         KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT);
1105
1106         /*
1107          * Figure out our bridge ID, use the lowest-valued MAC.
1108          * Include the bridge's own random MAC in the calculation.
1109          */
1110         mif = NULL;
1111
1112         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1113                 if ((bif->bif_flags & IFBIF_STP) == 0)
1114                         continue;
1115                 if (bif->bif_ifp->if_type != IFT_ETHER)
1116                         continue;
1117                 if (mif == NULL) {
1118                         mif = bif;
1119                         continue;
1120                 }
1121
1122                 bif->bif_port_id = (bif->bif_priority << 8) |
1123                                    (bif->bif_ifp->if_index & 0xff);
1124                 if (bstp_addr_cmp(IF_LLADDR(bif->bif_ifp),
1125                                   IF_LLADDR(mif->bif_ifp)) < 0) {
1126                         mif = bif;
1127                         continue;
1128                 }
1129         }
1130         if (mif == NULL) {
1131                 bstp_stop(sc);
1132                 return;
1133         }
1134
1135         if (bstp_addr_cmp(IF_LLADDR(sc->sc_ifp), IF_LLADDR(mif->bif_ifp)) < 0)
1136                 e_addr = IF_LLADDR(sc->sc_ifp);
1137         else
1138                 e_addr = IF_LLADDR(mif->bif_ifp);
1139
1140         sc->sc_bridge_id =
1141             (((uint64_t)sc->sc_bridge_priority) << 48) |
1142             (((uint64_t)e_addr[0]) << 40) |
1143             (((uint64_t)e_addr[1]) << 32) |
1144             (((uint64_t)e_addr[2]) << 24) |
1145             (((uint64_t)e_addr[3]) << 16) |
1146             (((uint64_t)e_addr[4]) << 8) |
1147             (((uint64_t)e_addr[5]));
1148
1149         /*
1150          * Remainder of setup.
1151          */
1152
1153         sc->sc_designated_root = sc->sc_bridge_id;
1154         sc->sc_designated_cost = 0;
1155         sc->sc_root_port = NULL;
1156
1157         sc->sc_max_age = sc->sc_bridge_max_age;
1158         sc->sc_hello_time = sc->sc_bridge_hello_time;
1159         sc->sc_forward_delay = sc->sc_bridge_forward_delay;
1160         sc->sc_topology_change_detected = 0;
1161         sc->sc_topology_change = 0;
1162         bstp_timer_stop(&sc->sc_tcn_timer);
1163         bstp_timer_stop(&sc->sc_topology_change_timer);
1164
1165         if (callout_pending(&sc->sc_bstpcallout) == 0)
1166                 callout_reset(&sc->sc_bstpcallout, hz,
1167                     bstp_tick, sc);
1168
1169         TAILQ_FOREACH_MUTABLE(bif, &sc->sc_iflists[mycpuid], bif_next, nbif) {
1170                 if (sc->sc_ifp->if_flags & IFF_LINK1)
1171                         bstp_timer_start(&bif->bif_link1_timer, 0);
1172                 if (bif->bif_flags & IFBIF_STP)
1173                         bstp_ifupdstatus(sc, bif);
1174                 else
1175                         bstp_disable_port(sc, bif);
1176
1177                 if (nbif != NULL && !nbif->bif_onlist) {
1178                         KKASSERT(bif->bif_onlist);
1179                         nbif = TAILQ_NEXT(bif, bif_next);
1180                 }
1181         }
1182
1183         bstp_port_state_selection(sc);
1184         bstp_config_bpdu_generation(sc);
1185         bstp_timer_start(&sc->sc_hello_timer, 0);
1186 }
1187
1188 void
1189 bstp_stop(struct bridge_softc *sc)
1190 {
1191         struct bridge_iflist *bif;
1192         struct lwkt_msg *lmsg;
1193
1194         KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT);
1195
1196         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1197                 bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED);
1198                 bstp_timer_stop(&bif->bif_hold_timer);
1199                 bstp_timer_stop(&bif->bif_message_age_timer);
1200                 bstp_timer_stop(&bif->bif_forward_delay_timer);
1201                 bstp_timer_stop(&bif->bif_link1_timer);
1202         }
1203
1204         callout_stop(&sc->sc_bstpcallout);
1205
1206         bstp_timer_stop(&sc->sc_topology_change_timer);
1207         bstp_timer_stop(&sc->sc_tcn_timer);
1208         bstp_timer_stop(&sc->sc_hello_timer);
1209
1210         crit_enter();
1211         lmsg = &sc->sc_bstptimemsg.lmsg;
1212         if ((lmsg->ms_flags & MSGF_DONE) == 0) {
1213                 /* Pending to be processed; drop it */
1214                 lwkt_dropmsg(lmsg);
1215         }
1216         crit_exit();
1217 }
1218
1219 static void
1220 bstp_initialize_port(struct bridge_softc *sc, struct bridge_iflist *bif)
1221 {
1222         int needs_adjust = (bif->bif_state == BSTP_IFSTATE_FORWARDING ||
1223                             bif->bif_state == BSTP_IFSTATE_BLOCKING ||
1224                             bif->bif_state == BSTP_IFSTATE_BONDED);
1225
1226         bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING);
1227         bstp_clear_peer_info(sc, bif);
1228         bif->bif_topology_change_acknowledge = 0;
1229         bif->bif_config_pending = 0;
1230         bif->bif_change_detection_enabled = 1;
1231         bstp_timer_stop(&bif->bif_message_age_timer);
1232         bstp_timer_stop(&bif->bif_forward_delay_timer);
1233         bstp_timer_stop(&bif->bif_hold_timer);
1234         bstp_timer_stop(&bif->bif_link1_timer);
1235         if (needs_adjust && (sc->sc_ifp->if_flags & IFF_LINK2))
1236                 bstp_adjust_bonded_states(sc, bif);
1237 }
1238
1239 static void
1240 bstp_enable_port(struct bridge_softc *sc, struct bridge_iflist *bif)
1241 {
1242         bstp_initialize_port(sc, bif);
1243         if (sc->sc_ifp->if_flags & IFF_LINK1)
1244                 bstp_timer_start(&bif->bif_link1_timer, 0);
1245         bstp_configuration_update(sc);
1246         bstp_port_state_selection(sc);
1247 }
1248
1249 static void
1250 bstp_disable_port(struct bridge_softc *sc, struct bridge_iflist *bif)
1251 {
1252         int was_forwarding = (bif->bif_state == BSTP_IFSTATE_FORWARDING);
1253         int iamroot;
1254
1255         iamroot = bstp_root_bridge(sc);
1256
1257         bstp_clear_peer_info(sc, bif);
1258         bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED);
1259         bif->bif_topology_change_acknowledge = 0;
1260         bif->bif_config_pending = 0;
1261         bstp_timer_stop(&bif->bif_message_age_timer);
1262         bstp_timer_stop(&bif->bif_forward_delay_timer);
1263         bstp_timer_stop(&bif->bif_link1_timer);
1264         bstp_configuration_update(sc);
1265         bstp_port_state_selection(sc);
1266         bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN);
1267         if (was_forwarding && (sc->sc_ifp->if_flags & IFF_LINK2))
1268                 bstp_adjust_bonded_states(sc, bif);
1269
1270         if (iamroot == 0 && bstp_root_bridge(sc)) {
1271                 sc->sc_max_age = sc->sc_bridge_max_age;
1272                 sc->sc_hello_time = sc->sc_bridge_hello_time;
1273                 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
1274
1275                 bstp_topology_change_detection(sc);
1276                 bstp_timer_stop(&sc->sc_tcn_timer);
1277                 bstp_config_bpdu_generation(sc);
1278                 bstp_timer_start(&sc->sc_hello_timer, 0);
1279         }
1280 }
1281
1282 void
1283 bstp_linkstate(struct ifnet *ifp, int state)
1284 {
1285         struct bridge_softc *sc;
1286         struct bridge_iflist *bif;
1287
1288         sc = ifp->if_bridge;
1289         ifnet_serialize_all(sc->sc_ifp);
1290
1291         /*
1292          * bstp_ifupdstatus() may block, but it is the last
1293          * operation of the member iface iteration, so we
1294          * don't need to use LIST_FOREACH_MUTABLE()+bif_onlist
1295          * check here.
1296          */
1297         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1298                 if ((bif->bif_flags & IFBIF_STP) == 0)
1299                         continue;
1300
1301                 if (bif->bif_ifp == ifp) {
1302                         bstp_ifupdstatus(sc, bif);
1303                         break;
1304                 }
1305         }
1306         ifnet_deserialize_all(sc->sc_ifp);
1307 }
1308
1309 static void
1310 bstp_ifupdstatus(struct bridge_softc *sc, struct bridge_iflist *bif)
1311 {
1312         struct ifnet *ifp = bif->bif_ifp;
1313         struct ifmediareq ifmr;
1314         int error = 0;
1315
1316         bzero((char *)&ifmr, sizeof(ifmr));
1317         ifnet_serialize_all(ifp);
1318         error = (*ifp->if_ioctl)(ifp, SIOCGIFMEDIA, (caddr_t)&ifmr, NULL);
1319         ifnet_deserialize_all(ifp);
1320
1321         if ((error == 0) && (ifp->if_flags & IFF_UP)) {
1322                 if (ifmr.ifm_status & IFM_ACTIVE) {
1323                         if (bif->bif_state == BSTP_IFSTATE_DISABLED)
1324                                 bstp_enable_port(sc, bif);
1325
1326                 } else {
1327                         if (bif->bif_state != BSTP_IFSTATE_DISABLED)
1328                                 bstp_disable_port(sc, bif);
1329                 }
1330                 return;
1331         }
1332
1333         if (bif->bif_state != BSTP_IFSTATE_DISABLED)
1334                 bstp_disable_port(sc, bif);
1335 }
1336
1337 static void
1338 bstp_tick(void *arg)
1339 {
1340         struct bridge_softc *sc = arg;
1341         struct lwkt_msg *lmsg;
1342
1343         KKASSERT(mycpuid == BRIDGE_CFGCPU);
1344
1345         crit_enter();
1346
1347         if (callout_pending(&sc->sc_bstpcallout) ||
1348             !callout_active(&sc->sc_bstpcallout)) {
1349                 crit_exit();
1350                 return;
1351         }
1352         callout_deactivate(&sc->sc_bstpcallout);
1353
1354         lmsg = &sc->sc_bstptimemsg.lmsg;
1355         KKASSERT(lmsg->ms_flags & MSGF_DONE);
1356         lwkt_sendmsg(BRIDGE_CFGPORT, lmsg);
1357
1358         crit_exit();
1359 }
1360
1361 void
1362 bstp_tick_handler(netmsg_t msg)
1363 {
1364         struct bridge_softc *sc = msg->lmsg.u.ms_resultp;
1365         struct bridge_iflist *bif;
1366
1367         KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT);
1368         crit_enter();
1369         /* Reply ASAP */
1370         lwkt_replymsg(&msg->lmsg, 0);
1371         crit_exit();
1372
1373         ifnet_serialize_all(sc->sc_ifp);
1374
1375         /*
1376          * NOTE:
1377          * We don't need to worry that member iface is ripped
1378          * from the per-cpu list during the blocking operation
1379          * in the loop body, since deletion is serialized by
1380          * BRIDGE_CFGPORT
1381          */
1382
1383         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1384                 if ((bif->bif_flags & IFBIF_STP) == 0)
1385                         continue;
1386                 /*
1387                  * XXX This can cause a lag in "link does away"
1388                  * XXX and "spanning tree gets updated".  We need
1389                  * XXX come sort of callback from the link state
1390                  * XXX update code to kick spanning tree.
1391                  * XXX --thorpej@NetBSD.org
1392                  */
1393                 bstp_ifupdstatus(sc, bif);
1394         }
1395
1396         if (bstp_timer_expired(&sc->sc_hello_timer, sc->sc_hello_time))
1397                 bstp_hello_timer_expiry(sc);
1398
1399         if (bstp_timer_expired(&sc->sc_tcn_timer, sc->sc_bridge_hello_time))
1400                 bstp_tcn_timer_expiry(sc);
1401
1402         if (bstp_timer_expired(&sc->sc_topology_change_timer,
1403             sc->sc_topology_change_time))
1404                 bstp_topology_change_timer_expiry(sc);
1405
1406         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1407                 if ((bif->bif_flags & IFBIF_STP) == 0)
1408                         continue;
1409                 if (bstp_timer_expired(&bif->bif_message_age_timer,
1410                     sc->sc_max_age))
1411                         bstp_message_age_timer_expiry(sc, bif);
1412         }
1413
1414         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1415                 if ((bif->bif_flags & IFBIF_STP) == 0)
1416                         continue;
1417                 if (bstp_timer_expired(&bif->bif_forward_delay_timer,
1418                     sc->sc_forward_delay))
1419                         bstp_forward_delay_timer_expiry(sc, bif);
1420
1421                 if (bstp_timer_expired(&bif->bif_hold_timer,
1422                     sc->sc_hold_time))
1423                         bstp_hold_timer_expiry(sc, bif);
1424
1425                 if (bstp_timer_expired(&bif->bif_link1_timer,
1426                     sc->sc_hello_time * 10))
1427                         bstp_link1_timer_expiry(sc, bif);
1428         }
1429
1430         if (sc->sc_ifp->if_flags & IFF_RUNNING)
1431                 callout_reset(&sc->sc_bstpcallout, hz, bstp_tick, sc);
1432
1433         ifnet_deserialize_all(sc->sc_ifp);
1434 }
1435
1436 static void
1437 bstp_timer_start(struct bridge_timer *t, uint16_t v)
1438 {
1439         t->value = v;
1440         t->active = 1;
1441 }
1442
1443 static void
1444 bstp_timer_stop(struct bridge_timer *t)
1445 {
1446         t->value = 0;
1447         t->active = 0;
1448 }
1449
1450 static int
1451 bstp_timer_expired(struct bridge_timer *t, uint16_t v)
1452 {
1453         if (t->active == 0)
1454                 return (0);
1455         t->value += BSTP_TICK_VAL;
1456         if (t->value >= v) {
1457                 bstp_timer_stop(t);
1458                 return (1);
1459         }
1460         return (0);
1461
1462 }