/* * Copyright (c) 2000 Jason L. Wright (jason@thought.net) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Jason L. Wright * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * $OpenBSD: bridgestp.c,v 1.5 2001/03/22 03:48:29 jason Exp $ * $NetBSD: bridgestp.c,v 1.5 2003/11/28 08:56:48 keihan Exp $ * $FreeBSD: src/sys/net/bridgestp.c,v 1.7 2005/10/11 02:58:32 thompsa Exp $ */ /* * Implementation of the spanning tree protocol as defined in * ISO/IEC Final DIS 15802-3 (IEEE P802.1D/D17), May 25, 1998. * (In English: IEEE 802.1D, Draft 17, 1998) */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* BPDU message types */ #define BSTP_MSGTYPE_CFG 0x00 /* Configuration */ #define BSTP_MSGTYPE_TCN 0x80 /* Topology chg notification */ /* BPDU flags */ #define BSTP_FLAG_TC 0x01 /* Topology change */ #define BSTP_FLAG_TCA 0x80 /* Topology change ack */ #define BSTP_MESSAGE_AGE_INCR (1 * 256) /* in 256ths of a second */ #define BSTP_TICK_VAL (1 * 256) /* in 256ths of a second */ /* * Because BPDU's do not make nicely aligned structures, two different * declarations are used: bstp_?bpdu (wire representation, packed) and * bstp_*_unit (internal, nicely aligned version). */ /* configuration bridge protocol data unit */ struct bstp_cbpdu { uint8_t cbu_dsap; /* LLC: destination sap */ uint8_t cbu_ssap; /* LLC: source sap */ uint8_t cbu_ctl; /* LLC: control */ uint16_t cbu_protoid; /* protocol id */ uint8_t cbu_protover; /* protocol version */ uint8_t cbu_bpdutype; /* message type */ uint8_t cbu_flags; /* flags (below) */ /* root id */ uint16_t cbu_rootpri; /* root priority */ uint8_t cbu_rootaddr[6]; /* root address */ uint32_t cbu_rootpathcost; /* root path cost */ /* bridge id */ uint16_t cbu_bridgepri; /* bridge priority */ uint8_t cbu_bridgeaddr[6]; /* bridge address */ uint16_t cbu_portid; /* port id */ uint16_t cbu_messageage; /* current message age */ uint16_t cbu_maxage; /* maximum age */ uint16_t cbu_hellotime; /* hello time */ uint16_t cbu_forwarddelay; /* forwarding delay */ } __attribute__((__packed__)); /* topology change notification bridge protocol data unit */ struct bstp_tbpdu { uint8_t tbu_dsap; /* LLC: destination sap */ uint8_t tbu_ssap; /* LLC: source sap */ uint8_t tbu_ctl; /* LLC: control */ uint16_t tbu_protoid; /* protocol id */ uint8_t tbu_protover; /* protocol version */ uint8_t tbu_bpdutype; /* message type */ } __attribute__((__packed__)); const uint8_t bstp_etheraddr[] = { 0x01, 0x80, 0xc2, 0x00, 0x00, 0x00 }; static void bstp_initialize_port(struct bridge_softc *, struct bridge_iflist *); static void bstp_ifupdstatus(struct bridge_softc *, struct bridge_iflist *); static void bstp_enable_port(struct bridge_softc *, struct bridge_iflist *); static void bstp_disable_port(struct bridge_softc *, struct bridge_iflist *); #ifdef notused static void bstp_enable_change_detection(struct bridge_iflist *); static void bstp_disable_change_detection(struct bridge_iflist *); #endif /* notused */ static int bstp_root_bridge(struct bridge_softc *sc); static void bstp_transmit_config(struct bridge_softc *, struct bridge_iflist *); static void bstp_transmit_tcn(struct bridge_softc *); static void bstp_received_config_bpdu(struct bridge_softc *, struct bridge_iflist *, struct bstp_config_unit *); static void bstp_received_tcn_bpdu(struct bridge_softc *, struct bridge_iflist *, struct bstp_tcn_unit *); static void bstp_record_config_information(struct bridge_softc *, struct bridge_iflist *, struct bstp_config_unit *); static void bstp_record_config_timeout_values(struct bridge_softc *, struct bstp_config_unit *); static void bstp_config_bpdu_generation(struct bridge_softc *); static void bstp_send_config_bpdu(struct bridge_softc *, struct bridge_iflist *, struct bstp_config_unit *); static void bstp_configuration_update(struct bridge_softc *); static void bstp_port_state_selection(struct bridge_softc *); static void bstp_clear_peer_info(struct bridge_softc *, struct bridge_iflist *); static void bstp_make_forwarding(struct bridge_softc *, struct bridge_iflist *); static void bstp_make_blocking(struct bridge_softc *, struct bridge_iflist *); static void bstp_make_l1blocking(struct bridge_softc *sc, struct bridge_iflist *bif); static void bstp_set_port_state(struct bridge_iflist *, uint8_t); #ifdef notused static void bstp_set_bridge_priority(struct bridge_softc *, uint64_t); static void bstp_set_port_priority(struct bridge_softc *, struct bridge_iflist *, uint16_t); static void bstp_set_path_cost(struct bridge_softc *, struct bridge_iflist *, uint32_t); #endif /* notused */ static void bstp_topology_change_detection(struct bridge_softc *); static void bstp_topology_change_acknowledged(struct bridge_softc *); static void bstp_acknowledge_topology_change(struct bridge_softc *, struct bridge_iflist *); static void bstp_tick(void *); static void bstp_timer_start(struct bridge_timer *, uint16_t); static void bstp_timer_stop(struct bridge_timer *); static int bstp_timer_expired(struct bridge_timer *, uint16_t); static void bstp_hold_timer_expiry(struct bridge_softc *, struct bridge_iflist *); static void bstp_message_age_timer_expiry(struct bridge_softc *, struct bridge_iflist *); static void bstp_forward_delay_timer_expiry(struct bridge_softc *, struct bridge_iflist *); static void bstp_topology_change_timer_expiry(struct bridge_softc *); static void bstp_tcn_timer_expiry(struct bridge_softc *); static void bstp_hello_timer_expiry(struct bridge_softc *); static int bstp_addr_cmp(const uint8_t *, const uint8_t *); /* * When transmitting a config we tack on our path cost to * our aggregated path-to-root cost. */ static void bstp_transmit_config(struct bridge_softc *sc, struct bridge_iflist *bif) { if (bif->bif_hold_timer.active) { bif->bif_config_pending = 1; return; } bif->bif_config_bpdu.cu_message_type = BSTP_MSGTYPE_CFG; bif->bif_config_bpdu.cu_rootid = sc->sc_designated_root; bif->bif_config_bpdu.cu_root_path_cost = sc->sc_designated_cost + bif->bif_path_cost; bif->bif_config_bpdu.cu_bridge_id = sc->sc_bridge_id; bif->bif_config_bpdu.cu_port_id = bif->bif_port_id; if (bstp_root_bridge(sc)) { bif->bif_config_bpdu.cu_message_age = 0; } else if (sc->sc_root_port) { bif->bif_config_bpdu.cu_message_age = sc->sc_root_port->bif_message_age_timer.value + BSTP_MESSAGE_AGE_INCR; } else { bif->bif_config_bpdu.cu_message_age = BSTP_MESSAGE_AGE_INCR; } bif->bif_config_bpdu.cu_max_age = sc->sc_max_age; bif->bif_config_bpdu.cu_hello_time = sc->sc_hello_time; bif->bif_config_bpdu.cu_forward_delay = sc->sc_forward_delay; bif->bif_config_bpdu.cu_topology_change_acknowledgment = bif->bif_topology_change_acknowledge; bif->bif_config_bpdu.cu_topology_change = sc->sc_topology_change; if (bif->bif_config_bpdu.cu_message_age < sc->sc_max_age || (sc->sc_ifp->if_flags & IFF_LINK1)) { bif->bif_topology_change_acknowledge = 0; bif->bif_config_pending = 0; bstp_send_config_bpdu(sc, bif, &bif->bif_config_bpdu); bstp_timer_start(&bif->bif_hold_timer, 0); } } static void bstp_send_config_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif, struct bstp_config_unit *cu) { struct ifnet *ifp; struct mbuf *m; struct ether_header *eh; struct bstp_cbpdu bpdu; ifp = bif->bif_ifp; if ((ifp->if_flags & IFF_RUNNING) == 0) return; MGETHDR(m, MB_DONTWAIT, MT_DATA); if (m == NULL) return; eh = mtod(m, struct ether_header *); m->m_pkthdr.rcvif = ifp; m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu); m->m_len = m->m_pkthdr.len; bpdu.cbu_ssap = bpdu.cbu_dsap = LLC_8021D_LSAP; bpdu.cbu_ctl = LLC_UI; bpdu.cbu_protoid = htons(0); bpdu.cbu_protover = 0; bpdu.cbu_bpdutype = cu->cu_message_type; bpdu.cbu_flags = (cu->cu_topology_change ? BSTP_FLAG_TC : 0) | (cu->cu_topology_change_acknowledgment ? BSTP_FLAG_TCA : 0); bpdu.cbu_rootpri = htons(cu->cu_rootid >> 48); bpdu.cbu_rootaddr[0] = cu->cu_rootid >> 40; bpdu.cbu_rootaddr[1] = cu->cu_rootid >> 32; bpdu.cbu_rootaddr[2] = cu->cu_rootid >> 24; bpdu.cbu_rootaddr[3] = cu->cu_rootid >> 16; bpdu.cbu_rootaddr[4] = cu->cu_rootid >> 8; bpdu.cbu_rootaddr[5] = cu->cu_rootid >> 0; bpdu.cbu_rootpathcost = htonl(cu->cu_root_path_cost); bpdu.cbu_bridgepri = htons(cu->cu_bridge_id >> 48); bpdu.cbu_bridgeaddr[0] = cu->cu_bridge_id >> 40; bpdu.cbu_bridgeaddr[1] = cu->cu_bridge_id >> 32; bpdu.cbu_bridgeaddr[2] = cu->cu_bridge_id >> 24; bpdu.cbu_bridgeaddr[3] = cu->cu_bridge_id >> 16; bpdu.cbu_bridgeaddr[4] = cu->cu_bridge_id >> 8; bpdu.cbu_bridgeaddr[5] = cu->cu_bridge_id >> 0; bpdu.cbu_portid = htons(cu->cu_port_id); bpdu.cbu_messageage = htons(cu->cu_message_age); bpdu.cbu_maxage = htons(cu->cu_max_age); bpdu.cbu_hellotime = htons(cu->cu_hello_time); bpdu.cbu_forwarddelay = htons(cu->cu_forward_delay); /* * Packets sent from the bridge always use the bridge MAC * as the source. */ memcpy(eh->ether_shost, IF_LLADDR(sc->sc_ifp), ETHER_ADDR_LEN); memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN); eh->ether_type = htons(sizeof(bpdu)); memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu)); bridge_enqueue(ifp, m); } static int bstp_root_bridge(struct bridge_softc *sc) { return (sc->sc_designated_root == sc->sc_bridge_id); } /* * Returns TRUE if the recorded information from our peer has a shorter * graph distance than our current best. */ int bstp_supersedes_port_info(struct bridge_softc *sc, struct bridge_iflist *bif) { if (bif->bif_peer_root < sc->sc_designated_root) return (1); if (bif->bif_peer_root > sc->sc_designated_root) return (0); /* * Both bif_peer_cost and sc_designated_cost have NOT added in * bif->bif_path_cost, so we can optimize it out. */ if (bif->bif_peer_cost < sc->sc_designated_cost) return (1); if (bif->bif_peer_cost > sc->sc_designated_cost) return (0); if (bif->bif_peer_bridge < sc->sc_designated_bridge) return (1); if (bif->bif_peer_bridge > sc->sc_designated_bridge) return (0); /* bridge_id or bridge+port collision w/peer returns TRUE */ if (bif->bif_peer_bridge != sc->sc_bridge_id) return (1); if (bif->bif_peer_port <= sc->sc_designated_port) return (1); return (0); } /* * The shorter graph distance represented by cu (most of which is also * already stored in our bif_peer_* fields) becomes the designated info. * * NOTE: sc_designated_cost does not include bif_path_cost, it is added * in later on a port-by-port basis as needed. */ static void bstp_record_config_information(struct bridge_softc *sc, struct bridge_iflist *bif, struct bstp_config_unit *cu) { sc->sc_designated_root = bif->bif_peer_root; sc->sc_designated_cost = bif->bif_peer_cost; sc->sc_designated_bridge = bif->bif_peer_bridge; sc->sc_designated_port = bif->bif_peer_port; bstp_timer_start(&bif->bif_message_age_timer, cu->cu_message_age); } static void bstp_record_config_timeout_values(struct bridge_softc *sc, struct bstp_config_unit *config) { sc->sc_max_age = config->cu_max_age; sc->sc_hello_time = config->cu_hello_time; sc->sc_forward_delay = config->cu_forward_delay; sc->sc_topology_change = config->cu_topology_change; } static void bstp_config_bpdu_generation(struct bridge_softc *sc) { struct bridge_iflist *bif, *nbif; TAILQ_FOREACH_MUTABLE(bif, &sc->sc_iflists[mycpuid], bif_next, nbif) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bif->bif_state != BSTP_IFSTATE_DISABLED && ((sc->sc_ifp->if_flags & IFF_LINK1) || (bif->bif_flags & IFBIF_DESIGNATED))) { bstp_transmit_config(sc, bif); } if (nbif != NULL && !nbif->bif_onlist) { KKASSERT(bif->bif_onlist); nbif = TAILQ_NEXT(bif, bif_next); } } } static void bstp_transmit_tcn(struct bridge_softc *sc) { struct bstp_tbpdu bpdu; struct ifnet *ifp; struct ether_header *eh; struct mbuf *m; if (sc->sc_root_port == NULL) /* all iterfaces disabled */ return; ifp = sc->sc_root_port->bif_ifp; if ((ifp->if_flags & IFF_RUNNING) == 0) return; MGETHDR(m, MB_DONTWAIT, MT_DATA); if (m == NULL) return; m->m_pkthdr.rcvif = ifp; m->m_pkthdr.len = sizeof(*eh) + sizeof(bpdu); m->m_len = m->m_pkthdr.len; eh = mtod(m, struct ether_header *); /* * Packets sent from the bridge always use the bridge MAC * as the source. */ memcpy(eh->ether_shost, IF_LLADDR(sc->sc_ifp), ETHER_ADDR_LEN); memcpy(eh->ether_dhost, bstp_etheraddr, ETHER_ADDR_LEN); eh->ether_type = htons(sizeof(bpdu)); bpdu.tbu_ssap = bpdu.tbu_dsap = LLC_8021D_LSAP; bpdu.tbu_ctl = LLC_UI; bpdu.tbu_protoid = 0; bpdu.tbu_protover = 0; bpdu.tbu_bpdutype = BSTP_MSGTYPE_TCN; memcpy(mtod(m, caddr_t) + sizeof(*eh), &bpdu, sizeof(bpdu)); bridge_enqueue(ifp, m); } /* * Recalculate sc->sc_designated* and sc->sc_root_port (if our bridge * is calculated to be the root bridge). We do this by initializing * the designated variables to point at us and then scan our peers. * Any uninitialized peers will have a max-value root. * * Clear IFBIF_DESIGNATED on any ports which no longer match the criteria * required to be a designated port. Only aged out ports and the root * port can be designated. * * If we win we do a second scan to determine which port on our bridge * is the best. */ static void bstp_configuration_update(struct bridge_softc *sc) { uint64_t designated_root = sc->sc_bridge_id; uint64_t designated_bridge = sc->sc_bridge_id; uint32_t designated_cost = 0xFFFFFFFFU; uint16_t designated_port = 65535; struct bridge_iflist *root_port = NULL; struct bridge_iflist *bif; /* * Resolve information from our peers. Aged peers will have * a maxed bif_peer_root and not come under consideration. */ TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bif->bif_state == BSTP_IFSTATE_DISABLED || bif->bif_state == BSTP_IFSTATE_L1BLOCKING) { continue; } if (bif->bif_peer_root > designated_root) continue; if (bif->bif_peer_root < designated_root) goto set_port; /* * NOTE: The designated_cost temporary variable already added * in the path code of the related root port. */ if (bif->bif_peer_cost + bif->bif_path_cost > designated_cost) continue; if (bif->bif_peer_cost + bif->bif_path_cost < designated_cost) goto set_port; if (bif->bif_peer_bridge > designated_bridge) continue; if (bif->bif_peer_bridge < designated_bridge) goto set_port; if (bif->bif_peer_port > designated_port) continue; if (bif->bif_peer_port < designated_port) goto set_port; /* * Same root, path cost, bridge, and port. Set the root * only if we do not already have it. */ if (root_port) continue; /* * New root port (from peers) * * NOTE: Temporarily add bif_path_cost into the designated * cost to reduce complexity in the loop, it will be * subtracted out when we are done. */ set_port: designated_root = bif->bif_peer_root; designated_cost = bif->bif_peer_cost + bif->bif_path_cost; designated_bridge = bif->bif_peer_bridge; designated_port = bif->bif_peer_port; root_port = bif; } /* * root_port will be NULL at the start here if all of our * peers are aged or are not as good a root as our bridge would * be. It can also be NULL due to all related links being * disabled. * * If the root winds up being our bridge scan again against local * information. Unconditionally update IFBIF_DESIGNATED. */ TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { bif->bif_flags &= ~(IFBIF_DESIGNATED | IFBIF_ROOT); if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bif->bif_state == BSTP_IFSTATE_DISABLED || bif->bif_state == BSTP_IFSTATE_L1BLOCKING) { continue; } /* * Set DESIGNATED for an aged or unknown peer. */ if (bif->bif_peer_bridge == 0xFFFFFFFFFFFFFFFFLLU) bif->bif_flags |= IFBIF_DESIGNATED; if (designated_root != sc->sc_bridge_id) continue; /* * This is only reached if our bridge is the root bridge, * select the root port (IFBIF_DESIGNATED is set at the * end). * * We do NOT use peer info here. */ if (bif->bif_path_cost > designated_cost) continue; if (bif->bif_path_cost < designated_cost) goto set_port2; if (bif->bif_port_id > designated_port) continue; if (bif->bif_port_id < designated_port) goto set_port2; /* degenerate case (possible peer collision w/our key */ /* * New port */ set_port2: designated_cost = bif->bif_path_cost; designated_bridge = sc->sc_bridge_id; designated_port = bif->bif_port_id; root_port = bif; } /* * Update aggregate information. The selected root port always * becomes a designated port (along with aged ports). This can * either be the port whos peer is closest to the root or it * can be one of our ports if our bridge is the root. * * The root cost we record in sc_designated_root does not include * bif_path_cost of the root port, since we may transmit this * out of any port we will add the cost back in later on on * a per-port basis. * * root_port can be NULL here (if all links are disabled) */ if (root_port) { sc->sc_designated_root = designated_root; sc->sc_designated_cost = designated_cost - root_port->bif_path_cost; sc->sc_designated_bridge = designated_bridge; sc->sc_designated_port = designated_port; root_port->bif_flags |= IFBIF_DESIGNATED | IFBIF_ROOT; } else { sc->sc_designated_root = designated_root; sc->sc_designated_cost = designated_cost; sc->sc_designated_bridge = designated_bridge; sc->sc_designated_port = designated_port; } sc->sc_root_port = root_port; } /* * Calculate the desired state for each interface link on our bridge. * * The best port will match against sc->sc_root_port (whether we are root * or whether that port is the closest to the root). We push this port * towards a FORWARDING state. * * Next come designated ports, either aged ports or ports with no peer info * (yet), or the peer who is closest to the root. We push this port towards * a FORWARDING state as well. * * Any remaining ports are pushed towards a BLOCKED state. Both sides of * the port (us and our peer) should wind up placing the two ends in this * state or bad things happen. */ static void bstp_port_state_selection(struct bridge_softc *sc) { struct bridge_iflist *bif, *nbif; TAILQ_FOREACH_MUTABLE(bif, &sc->sc_iflists[mycpuid], bif_next, nbif) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (sc->sc_root_port && bif->bif_info == sc->sc_root_port->bif_info) { bif->bif_config_pending = 0; bif->bif_topology_change_acknowledge = 0; bstp_make_forwarding(sc, bif); } else if (bif->bif_flags & IFBIF_DESIGNATED) { bstp_timer_stop(&bif->bif_message_age_timer); bstp_make_forwarding(sc, bif); } else { bif->bif_config_pending = 0; bif->bif_topology_change_acknowledge = 0; bstp_make_blocking(sc, bif); } if (nbif != NULL && !nbif->bif_onlist) { KKASSERT(bif->bif_onlist); nbif = TAILQ_NEXT(bif, bif_next); } } } /* * Clear peer info, effectively makes the port looked aged out. * It becomes a designated go-to port. */ static void bstp_clear_peer_info(struct bridge_softc *sc, struct bridge_iflist *bif) { bif->bif_peer_root = 0xFFFFFFFFFFFFFFFFLLU; bif->bif_peer_cost = 0xFFFFFFFFU; bif->bif_peer_bridge = 0xFFFFFFFFFFFFFFFFLLU; bif->bif_peer_port = 0xFFFFU; if (bif->bif_state != BSTP_IFSTATE_DISABLED && bif->bif_state != BSTP_IFSTATE_L1BLOCKING) { bif->bif_flags |= IFBIF_DESIGNATED; } } static void bstp_make_forwarding(struct bridge_softc *sc, struct bridge_iflist *bif) { if (bif->bif_state == BSTP_IFSTATE_BLOCKING) { bstp_set_port_state(bif, BSTP_IFSTATE_LISTENING); bstp_timer_start(&bif->bif_forward_delay_timer, 0); } } static void bstp_make_blocking(struct bridge_softc *sc, struct bridge_iflist *bif) { if (bif->bif_state != BSTP_IFSTATE_DISABLED && bif->bif_state != BSTP_IFSTATE_BLOCKING && bif->bif_state != BSTP_IFSTATE_L1BLOCKING) { if ((bif->bif_state == BSTP_IFSTATE_FORWARDING) || (bif->bif_state == BSTP_IFSTATE_LEARNING)) { if (bif->bif_change_detection_enabled) { bstp_topology_change_detection(sc); } } bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING); bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN); bstp_timer_stop(&bif->bif_forward_delay_timer); } } static void bstp_make_l1blocking(struct bridge_softc *sc, struct bridge_iflist *bif) { switch(bif->bif_state) { case BSTP_IFSTATE_LISTENING: case BSTP_IFSTATE_LEARNING: case BSTP_IFSTATE_FORWARDING: case BSTP_IFSTATE_BLOCKING: bstp_set_port_state(bif, BSTP_IFSTATE_L1BLOCKING); bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN); bstp_timer_stop(&bif->bif_forward_delay_timer); bstp_timer_stop(&bif->bif_link1_timer); if (bif->bif_flags & IFBIF_DESIGNATED) { bif->bif_flags &= ~IFBIF_DESIGNATED; bstp_configuration_update(sc); bstp_port_state_selection(sc); } break; default: break; } } static void bstp_set_port_state(struct bridge_iflist *bif, uint8_t state) { bif->bif_state = state; } static void bstp_topology_change_detection(struct bridge_softc *sc) { if (bstp_root_bridge(sc)) { sc->sc_topology_change = 1; bstp_timer_start(&sc->sc_topology_change_timer, 0); } else if (!sc->sc_topology_change_detected) { bstp_transmit_tcn(sc); bstp_timer_start(&sc->sc_tcn_timer, 0); } sc->sc_topology_change_detected = 1; } static void bstp_topology_change_acknowledged(struct bridge_softc *sc) { sc->sc_topology_change_detected = 0; bstp_timer_stop(&sc->sc_tcn_timer); } static void bstp_acknowledge_topology_change(struct bridge_softc *sc, struct bridge_iflist *bif) { bif->bif_topology_change_acknowledge = 1; bstp_transmit_config(sc, bif); } void bstp_input(struct bridge_softc *sc, struct bridge_iflist *bif, struct mbuf *m) { struct ether_header *eh; struct bstp_tbpdu tpdu; struct bstp_cbpdu cpdu; struct bstp_config_unit cu; struct bstp_tcn_unit tu; uint16_t len; if ((bif->bif_flags & IFBIF_STP) == 0) goto out; /* * The L1BLOCKING (ping pong failover) test needs to reset the * timer if LINK1 is active. */ if (bif->bif_state == BSTP_IFSTATE_L1BLOCKING) { bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING); if (sc->sc_ifp->if_flags & IFF_LINK1) bstp_timer_start(&bif->bif_link1_timer, 0); bstp_make_forwarding(sc, bif); } else if (sc->sc_ifp->if_flags & IFF_LINK1) { bstp_timer_start(&bif->bif_link1_timer, 0); } eh = mtod(m, struct ether_header *); len = ntohs(eh->ether_type); if (len < sizeof(tpdu)) goto out; m_adj(m, ETHER_HDR_LEN); if (m->m_pkthdr.len > len) m_adj(m, len - m->m_pkthdr.len); if (m->m_len < sizeof(tpdu) && (m = m_pullup(m, sizeof(tpdu))) == NULL) goto out; memcpy(&tpdu, mtod(m, caddr_t), sizeof(tpdu)); if (tpdu.tbu_dsap != LLC_8021D_LSAP || tpdu.tbu_ssap != LLC_8021D_LSAP || tpdu.tbu_ctl != LLC_UI) goto out; if (tpdu.tbu_protoid != 0 || tpdu.tbu_protover != 0) goto out; switch (tpdu.tbu_bpdutype) { case BSTP_MSGTYPE_TCN: tu.tu_message_type = tpdu.tbu_bpdutype; bstp_received_tcn_bpdu(sc, bif, &tu); break; case BSTP_MSGTYPE_CFG: if (m->m_len < sizeof(cpdu) && (m = m_pullup(m, sizeof(cpdu))) == NULL) goto out; memcpy(&cpdu, mtod(m, caddr_t), sizeof(cpdu)); cu.cu_rootid = (((uint64_t)ntohs(cpdu.cbu_rootpri)) << 48) | (((uint64_t)cpdu.cbu_rootaddr[0]) << 40) | (((uint64_t)cpdu.cbu_rootaddr[1]) << 32) | (((uint64_t)cpdu.cbu_rootaddr[2]) << 24) | (((uint64_t)cpdu.cbu_rootaddr[3]) << 16) | (((uint64_t)cpdu.cbu_rootaddr[4]) << 8) | (((uint64_t)cpdu.cbu_rootaddr[5]) << 0); cu.cu_bridge_id = (((uint64_t)ntohs(cpdu.cbu_bridgepri)) << 48) | (((uint64_t)cpdu.cbu_bridgeaddr[0]) << 40) | (((uint64_t)cpdu.cbu_bridgeaddr[1]) << 32) | (((uint64_t)cpdu.cbu_bridgeaddr[2]) << 24) | (((uint64_t)cpdu.cbu_bridgeaddr[3]) << 16) | (((uint64_t)cpdu.cbu_bridgeaddr[4]) << 8) | (((uint64_t)cpdu.cbu_bridgeaddr[5]) << 0); cu.cu_root_path_cost = ntohl(cpdu.cbu_rootpathcost); cu.cu_message_age = ntohs(cpdu.cbu_messageage); cu.cu_max_age = ntohs(cpdu.cbu_maxage); cu.cu_hello_time = ntohs(cpdu.cbu_hellotime); cu.cu_forward_delay = ntohs(cpdu.cbu_forwarddelay); cu.cu_port_id = ntohs(cpdu.cbu_portid); cu.cu_message_type = cpdu.cbu_bpdutype; cu.cu_topology_change_acknowledgment = (cpdu.cbu_flags & BSTP_FLAG_TCA) ? 1 : 0; cu.cu_topology_change = (cpdu.cbu_flags & BSTP_FLAG_TC) ? 1 : 0; bstp_received_config_bpdu(sc, bif, &cu); break; default: goto out; } out: if (m) m_freem(m); } static void bstp_received_config_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif, struct bstp_config_unit *cu) { int iamroot; iamroot = bstp_root_bridge(sc); if (bif->bif_state != BSTP_IFSTATE_DISABLED) { /* * Record information from peer. The peer_cost field * does not include the local bif->bif_path_cost, it will * be added in as needed (since it can be modified manually * this way we don't have to worry about fixups). */ bif->bif_peer_root = cu->cu_rootid; bif->bif_peer_cost = cu->cu_root_path_cost; bif->bif_peer_bridge = cu->cu_bridge_id; bif->bif_peer_port = cu->cu_port_id; if (bstp_supersedes_port_info(sc, bif)) { bstp_record_config_information(sc, bif, cu); bstp_configuration_update(sc); bstp_port_state_selection(sc); /* * If our bridge loses its root status (?) * * Hello's (unsolicited CFG packets) are generated * every hello period of LINK1 is set, otherwise * we are no longer the root bridge and must stop * generating unsolicited CFG packets. */ if (iamroot && bstp_root_bridge(sc) == 0) { if ((sc->sc_ifp->if_flags & IFF_LINK1) == 0) bstp_timer_stop(&sc->sc_hello_timer); if (sc->sc_topology_change_detected) { bstp_timer_stop( &sc->sc_topology_change_timer); bstp_transmit_tcn(sc); bstp_timer_start(&sc->sc_tcn_timer, 0); } } if (sc->sc_root_port && bif->bif_info == sc->sc_root_port->bif_info) { bstp_record_config_timeout_values(sc, cu); bstp_config_bpdu_generation(sc); if (cu->cu_topology_change_acknowledgment) bstp_topology_change_acknowledged(sc); } } else if (bif->bif_flags & IFBIF_DESIGNATED) { /* * Update designated ports (aged out peers or * the port closest to the root) at a faster pace. * * Clear our designated flag if we aren't marked * as the root port. */ bstp_transmit_config(sc, bif); if ((bif->bif_flags & IFBIF_ROOT) == 0) { bif->bif_flags &= ~IFBIF_DESIGNATED; bstp_configuration_update(sc); bstp_port_state_selection(sc); } } } } static void bstp_received_tcn_bpdu(struct bridge_softc *sc, struct bridge_iflist *bif, struct bstp_tcn_unit *tcn) { if (bif->bif_state != BSTP_IFSTATE_DISABLED && (bif->bif_flags & IFBIF_DESIGNATED)) { bstp_topology_change_detection(sc); bstp_acknowledge_topology_change(sc, bif); } } /* * link1 forces continuous hello's (the bridge interface must be cycled * to start them up), so keep the timer hot if that is the case, otherwise * only send HELLO's if we are the root. */ static void bstp_hello_timer_expiry(struct bridge_softc *sc) { bstp_config_bpdu_generation(sc); if ((sc->sc_ifp->if_flags & IFF_LINK1) || bstp_root_bridge(sc)) bstp_timer_start(&sc->sc_hello_timer, 0); } static void bstp_message_age_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif) { int iamroot; iamroot = bstp_root_bridge(sc); bstp_clear_peer_info(sc, bif); bstp_configuration_update(sc); bstp_port_state_selection(sc); /* * If we've become the root and were not the root before * we have some cleanup to do. This also occurs if we * wind up being completely isolated. */ if (iamroot == 0 && bstp_root_bridge(sc)) { sc->sc_max_age = sc->sc_bridge_max_age; sc->sc_hello_time = sc->sc_bridge_hello_time; sc->sc_forward_delay = sc->sc_bridge_forward_delay; bstp_topology_change_detection(sc); bstp_timer_stop(&sc->sc_tcn_timer); bstp_config_bpdu_generation(sc); bstp_timer_start(&sc->sc_hello_timer, 0); } } static void bstp_forward_delay_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif) { if (bif->bif_state == BSTP_IFSTATE_LISTENING) { bstp_set_port_state(bif, BSTP_IFSTATE_LEARNING); bstp_timer_start(&bif->bif_forward_delay_timer, 0); } else if (bif->bif_state == BSTP_IFSTATE_LEARNING) { bstp_set_port_state(bif, BSTP_IFSTATE_FORWARDING); if (sc->sc_designated_bridge == sc->sc_bridge_id && bif->bif_change_detection_enabled) { bstp_topology_change_detection(sc); } } } static void bstp_tcn_timer_expiry(struct bridge_softc *sc) { bstp_transmit_tcn(sc); bstp_timer_start(&sc->sc_tcn_timer, 0); } static void bstp_topology_change_timer_expiry(struct bridge_softc *sc) { sc->sc_topology_change_detected = 0; sc->sc_topology_change = 0; } static void bstp_hold_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif) { if (bif->bif_config_pending) bstp_transmit_config(sc, bif); } /* * If no traffic received directly on this port for the specified * period with link1 set we go into a special blocking mode to * fail-over traffic to another port. */ static void bstp_link1_timer_expiry(struct bridge_softc *sc, struct bridge_iflist *bif) { if (sc->sc_ifp->if_flags & IFF_LINK1) bstp_make_l1blocking(sc, bif); } static int bstp_addr_cmp(const uint8_t *a, const uint8_t *b) { int i, d; for (i = 0, d = 0; i < ETHER_ADDR_LEN && d == 0; i++) { d = ((int)a[i]) - ((int)b[i]); } return (d); } void bstp_initialization(struct bridge_softc *sc) { struct bridge_iflist *bif, *mif, *nbif; u_char *e_addr; KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT); /* * Figure out our bridge ID, use the lowest-valued MAC. * Include the bridge's own random MAC in the calculation. */ mif = NULL; TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bif->bif_ifp->if_type != IFT_ETHER) continue; if (mif == NULL) { mif = bif; continue; } bif->bif_port_id = (bif->bif_priority << 8) | (bif->bif_ifp->if_index & 0xff); if (bstp_addr_cmp(IF_LLADDR(bif->bif_ifp), IF_LLADDR(mif->bif_ifp)) < 0) { mif = bif; continue; } } if (mif == NULL) { bstp_stop(sc); return; } if (bstp_addr_cmp(IF_LLADDR(sc->sc_ifp), IF_LLADDR(mif->bif_ifp)) < 0) e_addr = IF_LLADDR(sc->sc_ifp); else e_addr = IF_LLADDR(mif->bif_ifp); sc->sc_bridge_id = (((uint64_t)sc->sc_bridge_priority) << 48) | (((uint64_t)e_addr[0]) << 40) | (((uint64_t)e_addr[1]) << 32) | (((uint64_t)e_addr[2]) << 24) | (((uint64_t)e_addr[3]) << 16) | (((uint64_t)e_addr[4]) << 8) | (((uint64_t)e_addr[5])); /* * Remainder of setup. */ sc->sc_designated_root = sc->sc_bridge_id; sc->sc_designated_cost = 0; sc->sc_root_port = NULL; sc->sc_max_age = sc->sc_bridge_max_age; sc->sc_hello_time = sc->sc_bridge_hello_time; sc->sc_forward_delay = sc->sc_bridge_forward_delay; sc->sc_topology_change_detected = 0; sc->sc_topology_change = 0; bstp_timer_stop(&sc->sc_tcn_timer); bstp_timer_stop(&sc->sc_topology_change_timer); if (callout_pending(&sc->sc_bstpcallout) == 0) callout_reset(&sc->sc_bstpcallout, hz, bstp_tick, sc); TAILQ_FOREACH_MUTABLE(bif, &sc->sc_iflists[mycpuid], bif_next, nbif) { if (sc->sc_ifp->if_flags & IFF_LINK1) bstp_timer_start(&bif->bif_link1_timer, 0); if (bif->bif_flags & IFBIF_STP) bstp_ifupdstatus(sc, bif); else bstp_disable_port(sc, bif); if (nbif != NULL && !nbif->bif_onlist) { KKASSERT(bif->bif_onlist); nbif = TAILQ_NEXT(bif, bif_next); } } bstp_port_state_selection(sc); bstp_config_bpdu_generation(sc); bstp_timer_start(&sc->sc_hello_timer, 0); } void bstp_stop(struct bridge_softc *sc) { struct bridge_iflist *bif; struct lwkt_msg *lmsg; KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT); TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED); bstp_timer_stop(&bif->bif_hold_timer); bstp_timer_stop(&bif->bif_message_age_timer); bstp_timer_stop(&bif->bif_forward_delay_timer); bstp_timer_stop(&bif->bif_link1_timer); } callout_stop(&sc->sc_bstpcallout); bstp_timer_stop(&sc->sc_topology_change_timer); bstp_timer_stop(&sc->sc_tcn_timer); bstp_timer_stop(&sc->sc_hello_timer); crit_enter(); lmsg = &sc->sc_bstptimemsg.lmsg; if ((lmsg->ms_flags & MSGF_DONE) == 0) { /* Pending to be processed; drop it */ lwkt_dropmsg(lmsg); } crit_exit(); } static void bstp_initialize_port(struct bridge_softc *sc, struct bridge_iflist *bif) { bstp_set_port_state(bif, BSTP_IFSTATE_BLOCKING); bstp_clear_peer_info(sc, bif); bif->bif_topology_change_acknowledge = 0; bif->bif_config_pending = 0; bif->bif_change_detection_enabled = 1; bstp_timer_stop(&bif->bif_message_age_timer); bstp_timer_stop(&bif->bif_forward_delay_timer); bstp_timer_stop(&bif->bif_hold_timer); bstp_timer_stop(&bif->bif_link1_timer); } static void bstp_enable_port(struct bridge_softc *sc, struct bridge_iflist *bif) { bstp_initialize_port(sc, bif); if (sc->sc_ifp->if_flags & IFF_LINK1) bstp_timer_start(&bif->bif_link1_timer, 0); bstp_port_state_selection(sc); } static void bstp_disable_port(struct bridge_softc *sc, struct bridge_iflist *bif) { int iamroot; iamroot = bstp_root_bridge(sc); bstp_clear_peer_info(sc, bif); bstp_set_port_state(bif, BSTP_IFSTATE_DISABLED); bif->bif_topology_change_acknowledge = 0; bif->bif_config_pending = 0; bstp_timer_stop(&bif->bif_message_age_timer); bstp_timer_stop(&bif->bif_forward_delay_timer); bstp_timer_stop(&bif->bif_link1_timer); bstp_configuration_update(sc); bstp_port_state_selection(sc); bridge_rtdelete(sc, bif->bif_ifp, IFBF_FLUSHDYN); if (iamroot == 0 && bstp_root_bridge(sc)) { sc->sc_max_age = sc->sc_bridge_max_age; sc->sc_hello_time = sc->sc_bridge_hello_time; sc->sc_forward_delay = sc->sc_bridge_forward_delay; bstp_topology_change_detection(sc); bstp_timer_stop(&sc->sc_tcn_timer); bstp_config_bpdu_generation(sc); bstp_timer_start(&sc->sc_hello_timer, 0); } } void bstp_linkstate(struct ifnet *ifp, int state) { struct bridge_softc *sc; struct bridge_iflist *bif; sc = ifp->if_bridge; ifnet_serialize_all(sc->sc_ifp); /* * bstp_ifupdstatus() may block, but it is the last * operation of the member iface iteration, so we * don't need to use LIST_FOREACH_MUTABLE()+bif_onlist * check here. */ TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bif->bif_ifp == ifp) { bstp_ifupdstatus(sc, bif); break; } } ifnet_deserialize_all(sc->sc_ifp); } static void bstp_ifupdstatus(struct bridge_softc *sc, struct bridge_iflist *bif) { struct ifnet *ifp = bif->bif_ifp; struct ifmediareq ifmr; int error = 0; bzero((char *)&ifmr, sizeof(ifmr)); ifnet_serialize_all(ifp); error = (*ifp->if_ioctl)(ifp, SIOCGIFMEDIA, (caddr_t)&ifmr, NULL); ifnet_deserialize_all(ifp); if ((error == 0) && (ifp->if_flags & IFF_UP)) { if (ifmr.ifm_status & IFM_ACTIVE) { if (bif->bif_state == BSTP_IFSTATE_DISABLED) bstp_enable_port(sc, bif); } else { if (bif->bif_state != BSTP_IFSTATE_DISABLED) bstp_disable_port(sc, bif); } return; } if (bif->bif_state != BSTP_IFSTATE_DISABLED) bstp_disable_port(sc, bif); } static void bstp_tick(void *arg) { struct bridge_softc *sc = arg; struct lwkt_msg *lmsg; KKASSERT(mycpuid == BRIDGE_CFGCPU); crit_enter(); if (callout_pending(&sc->sc_bstpcallout) || !callout_active(&sc->sc_bstpcallout)) { crit_exit(); return; } callout_deactivate(&sc->sc_bstpcallout); lmsg = &sc->sc_bstptimemsg.lmsg; KKASSERT(lmsg->ms_flags & MSGF_DONE); lwkt_sendmsg(BRIDGE_CFGPORT, lmsg); crit_exit(); } void bstp_tick_handler(netmsg_t msg) { struct bridge_softc *sc = msg->lmsg.u.ms_resultp; struct bridge_iflist *bif; KKASSERT(&curthread->td_msgport == BRIDGE_CFGPORT); crit_enter(); /* Reply ASAP */ lwkt_replymsg(&msg->lmsg, 0); crit_exit(); ifnet_serialize_all(sc->sc_ifp); /* * NOTE: * We don't need to worry that member iface is ripped * from the per-cpu list during the blocking operation * in the loop body, since deletion is serialized by * BRIDGE_CFGPORT */ TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; /* * XXX This can cause a lag in "link does away" * XXX and "spanning tree gets updated". We need * XXX come sort of callback from the link state * XXX update code to kick spanning tree. * XXX --thorpej@NetBSD.org */ bstp_ifupdstatus(sc, bif); } if (bstp_timer_expired(&sc->sc_hello_timer, sc->sc_hello_time)) bstp_hello_timer_expiry(sc); if (bstp_timer_expired(&sc->sc_tcn_timer, sc->sc_bridge_hello_time)) bstp_tcn_timer_expiry(sc); if (bstp_timer_expired(&sc->sc_topology_change_timer, sc->sc_topology_change_time)) bstp_topology_change_timer_expiry(sc); TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bstp_timer_expired(&bif->bif_message_age_timer, sc->sc_max_age)) bstp_message_age_timer_expiry(sc, bif); } TAILQ_FOREACH(bif, &sc->sc_iflists[mycpuid], bif_next) { if ((bif->bif_flags & IFBIF_STP) == 0) continue; if (bstp_timer_expired(&bif->bif_forward_delay_timer, sc->sc_forward_delay)) bstp_forward_delay_timer_expiry(sc, bif); if (bstp_timer_expired(&bif->bif_hold_timer, sc->sc_hold_time)) bstp_hold_timer_expiry(sc, bif); if (bstp_timer_expired(&bif->bif_link1_timer, sc->sc_hello_time * 10)) bstp_link1_timer_expiry(sc, bif); } if (sc->sc_ifp->if_flags & IFF_RUNNING) callout_reset(&sc->sc_bstpcallout, hz, bstp_tick, sc); ifnet_deserialize_all(sc->sc_ifp); } static void bstp_timer_start(struct bridge_timer *t, uint16_t v) { t->value = v; t->active = 1; } static void bstp_timer_stop(struct bridge_timer *t) { t->value = 0; t->active = 0; } static int bstp_timer_expired(struct bridge_timer *t, uint16_t v) { if (t->active == 0) return (0); t->value += BSTP_TICK_VAL; if (t->value >= v) { bstp_timer_stop(t); return (1); } return (0); }