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_port_state_selection(sc);
1246 }
1247
1248 static void
1249 bstp_disable_port(struct bridge_softc *sc, struct bridge_iflist *bif)
1250 {
1251         int was_forwarding = (bif->bif_state == BSTP_IFSTATE_FORWARDING);
1252         int iamroot;
1253
1254         iamroot = bstp_root_bridge(sc);
1255
1256         bstp_clear_peer_info(sc, bif);
1257         bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED);
1258         bif->bif_topology_change_acknowledge = 0;
1259         bif->bif_config_pending = 0;
1260         bstp_timer_stop(&bif->bif_message_age_timer);
1261         bstp_timer_stop(&bif->bif_forward_delay_timer);
1262         bstp_timer_stop(&bif->bif_link1_timer);
1263         bstp_configuration_update(sc);
1264         bstp_port_state_selection(sc);
1265         bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN);
1266         if (was_forwarding && (sc->sc_ifp->if_flags & IFF_LINK2))
1267                 bstp_adjust_bonded_states(sc, bif);
1268
1269         if (iamroot == 0 && bstp_root_bridge(sc)) {
1270                 sc->sc_max_age = sc->sc_bridge_max_age;
1271                 sc->sc_hello_time = sc->sc_bridge_hello_time;
1272                 sc->sc_forward_delay = sc->sc_bridge_forward_delay;
1273
1274                 bstp_topology_change_detection(sc);
1275                 bstp_timer_stop(&sc->sc_tcn_timer);
1276                 bstp_config_bpdu_generation(sc);
1277                 bstp_timer_start(&sc->sc_hello_timer, 0);
1278         }
1279 }
1280
1281 void
1282 bstp_linkstate(struct ifnet *ifp, int state)
1283 {
1284         struct bridge_softc *sc;
1285         struct bridge_iflist *bif;
1286
1287         sc = ifp->if_bridge;
1288         ifnet_serialize_all(sc->sc_ifp);
1289
1290         /*
1291          * bstp_ifupdstatus() may block, but it is the last
1292          * operation of the member iface iteration, so we
1293          * don't need to use LIST_FOREACH_MUTABLE()+bif_onlist
1294          * check here.
1295          */
1296         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1297                 if ((bif->bif_flags & IFBIF_STP) == 0)
1298                         continue;
1299
1300                 if (bif->bif_ifp == ifp) {
1301                         bstp_ifupdstatus(sc, bif);
1302                         break;
1303                 }
1304         }
1305         ifnet_deserialize_all(sc->sc_ifp);
1306 }
1307
1308 static void
1309 bstp_ifupdstatus(struct bridge_softc *sc, struct bridge_iflist *bif)
1310 {
1311         struct ifnet *ifp = bif->bif_ifp;
1312         struct ifmediareq ifmr;
1313         int error = 0;
1314
1315         bzero((char *)&ifmr, sizeof(ifmr));
1316         ifnet_serialize_all(ifp);
1317         error = (*ifp->if_ioctl)(ifp, SIOCGIFMEDIA, (caddr_t)&ifmr, NULL);
1318         ifnet_deserialize_all(ifp);
1319
1320         if ((error == 0) && (ifp->if_flags & IFF_UP)) {
1321                 if (ifmr.ifm_status & IFM_ACTIVE) {
1322                         if (bif->bif_state == BSTP_IFSTATE_DISABLED)
1323                                 bstp_enable_port(sc, bif);
1324
1325                 } else {
1326                         if (bif->bif_state != BSTP_IFSTATE_DISABLED)
1327                                 bstp_disable_port(sc, bif);
1328                 }
1329                 return;
1330         }
1331
1332         if (bif->bif_state != BSTP_IFSTATE_DISABLED)
1333                 bstp_disable_port(sc, bif);
1334 }
1335
1336 static void
1337 bstp_tick(void *arg)
1338 {
1339         struct bridge_softc *sc = arg;
1340         struct lwkt_msg *lmsg;
1341
1342         KKASSERT(mycpuid == BRIDGE_CFGCPU);
1343
1344         crit_enter();
1345
1346         if (callout_pending(&sc->sc_bstpcallout) ||
1347             !callout_active(&sc->sc_bstpcallout)) {
1348                 crit_exit();
1349                 return;
1350         }
1351         callout_deactivate(&sc->sc_bstpcallout);
1352
1353         lmsg = &sc->sc_bstptimemsg.lmsg;
1354         KKASSERT(lmsg->ms_flags & MSGF_DONE);
1355         lwkt_sendmsg(BRIDGE_CFGPORT, lmsg);
1356
1357         crit_exit();
1358 }
1359
1360 void
1361 bstp_tick_handler(netmsg_t msg)
1362 {
1363         struct bridge_softc *sc = msg->lmsg.u.ms_resultp;
1364         struct bridge_iflist *bif;
1365
1366         KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT);
1367         crit_enter();
1368         /* Reply ASAP */
1369         lwkt_replymsg(&msg->lmsg, 0);
1370         crit_exit();
1371
1372         ifnet_serialize_all(sc->sc_ifp);
1373
1374         /*
1375          * NOTE:
1376          * We don't need to worry that member iface is ripped
1377          * from the per-cpu list during the blocking operation
1378          * in the loop body, since deletion is serialized by
1379          * BRIDGE_CFGPORT
1380          */
1381
1382         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1383                 if ((bif->bif_flags & IFBIF_STP) == 0)
1384                         continue;
1385                 /*
1386                  * XXX This can cause a lag in "link does away"
1387                  * XXX and "spanning tree gets updated".  We need
1388                  * XXX come sort of callback from the link state
1389                  * XXX update code to kick spanning tree.
1390                  * XXX --thorpej@NetBSD.org
1391                  */
1392                 bstp_ifupdstatus(sc, bif);
1393         }
1394
1395         if (bstp_timer_expired(&sc->sc_hello_timer, sc->sc_hello_time))
1396                 bstp_hello_timer_expiry(sc);
1397
1398         if (bstp_timer_expired(&sc->sc_tcn_timer, sc->sc_bridge_hello_time))
1399                 bstp_tcn_timer_expiry(sc);
1400
1401         if (bstp_timer_expired(&sc->sc_topology_change_timer,
1402             sc->sc_topology_change_time))
1403                 bstp_topology_change_timer_expiry(sc);
1404
1405         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1406                 if ((bif->bif_flags & IFBIF_STP) == 0)
1407                         continue;
1408                 if (bstp_timer_expired(&bif->bif_message_age_timer,
1409                     sc->sc_max_age))
1410                         bstp_message_age_timer_expiry(sc, bif);
1411         }
1412
1413         TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) {
1414                 if ((bif->bif_flags & IFBIF_STP) == 0)
1415                         continue;
1416                 if (bstp_timer_expired(&bif->bif_forward_delay_timer,
1417                     sc->sc_forward_delay))
1418                         bstp_forward_delay_timer_expiry(sc, bif);
1419
1420                 if (bstp_timer_expired(&bif->bif_hold_timer,
1421                     sc->sc_hold_time))
1422                         bstp_hold_timer_expiry(sc, bif);
1423
1424                 if (bstp_timer_expired(&bif->bif_link1_timer,
1425                     sc->sc_hello_time * 10))
1426                         bstp_link1_timer_expiry(sc, bif);
1427         }
1428
1429         if (sc->sc_ifp->if_flags & IFF_RUNNING)
1430                 callout_reset(&sc->sc_bstpcallout, hz, bstp_tick, sc);
1431
1432         ifnet_deserialize_all(sc->sc_ifp);
1433 }
1434
1435 static void
1436 bstp_timer_start(struct bridge_timer *t, uint16_t v)
1437 {
1438         t->value = v;
1439         t->active = 1;
1440 }
1441
1442 static void
1443 bstp_timer_stop(struct bridge_timer *t)
1444 {
1445         t->value = 0;
1446         t->active = 0;
1447 }
1448
1449 static int
1450 bstp_timer_expired(struct bridge_timer *t, uint16_t v)
1451 {
1452         if (t->active == 0)
1453                 return (0);
1454         t->value += BSTP_TICK_VAL;
1455         if (t->value >= v) {
1456                 bstp_timer_stop(t);
1457                 return (1);
1458         }
1459         return (0);
1460
1461 }