/* $OpenBSD: neighbor.c,v 1.50 2021/11/03 21:40:03 sthen Exp $ */ /* * Copyright (c) 2005 Claudio Jeker * Copyright (c) 2004, 2005 Esben Norby * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ospfd.h" #include "ospf.h" #include "ospfe.h" #include "log.h" #include "rde.h" int nbr_adj_ok(struct nbr *); LIST_HEAD(nbr_head, nbr); struct nbr_table { struct nbr_head *hashtbl; u_int32_t hashmask; } nbrtable; #define NBR_HASH(x) \ &nbrtable.hashtbl[(x) & nbrtable.hashmask] u_int32_t peercnt = NBR_CNTSTART; struct { int state; enum nbr_event event; enum nbr_action action; int new_state; /* 0 means action decides or unchanged */ } nbr_fsm_tbl[] = { /* current state event that happened action to take resulting state */ {NBR_STA_ACTIVE, NBR_EVT_HELLO_RCVD, NBR_ACT_RST_ITIMER, 0}, {NBR_STA_BIDIR, NBR_EVT_2_WAY_RCVD, NBR_ACT_NOTHING, 0}, {NBR_STA_INIT, NBR_EVT_1_WAY_RCVD, NBR_ACT_NOTHING, 0}, {NBR_STA_DOWN, NBR_EVT_HELLO_RCVD, NBR_ACT_STRT_ITIMER, NBR_STA_INIT}, {NBR_STA_ATTEMPT, NBR_EVT_HELLO_RCVD, NBR_ACT_RST_ITIMER, NBR_STA_INIT}, {NBR_STA_INIT, NBR_EVT_2_WAY_RCVD, NBR_ACT_EVAL, 0}, {NBR_STA_XSTRT, NBR_EVT_NEG_DONE, NBR_ACT_SNAP, 0}, {NBR_STA_SNAP, NBR_EVT_SNAP_DONE, NBR_ACT_SNAP_DONE, NBR_STA_XCHNG}, {NBR_STA_XCHNG, NBR_EVT_XCHNG_DONE, NBR_ACT_XCHNG_DONE, 0}, {NBR_STA_LOAD, NBR_EVT_LOAD_DONE, NBR_ACT_NOTHING, NBR_STA_FULL}, {NBR_STA_2_WAY, NBR_EVT_ADJ_OK, NBR_ACT_EVAL, 0}, {NBR_STA_ADJFORM, NBR_EVT_ADJ_OK, NBR_ACT_ADJ_OK, 0}, {NBR_STA_PRELIM, NBR_EVT_ADJ_OK, NBR_ACT_HELLO_CHK, 0}, {NBR_STA_ADJFORM, NBR_EVT_ADJTMOUT, NBR_ACT_RESTRT_DD, 0}, {NBR_STA_FLOOD, NBR_EVT_SEQ_NUM_MIS, NBR_ACT_RESTRT_DD, 0}, {NBR_STA_FLOOD, NBR_EVT_BAD_LS_REQ, NBR_ACT_RESTRT_DD, 0}, {NBR_STA_ANY, NBR_EVT_KILL_NBR, NBR_ACT_DEL, NBR_STA_DOWN}, {NBR_STA_ANY, NBR_EVT_LL_DOWN, NBR_ACT_DEL, NBR_STA_DOWN}, {NBR_STA_ANY, NBR_EVT_ITIMER, NBR_ACT_DEL, NBR_STA_DOWN}, {NBR_STA_BIDIR, NBR_EVT_1_WAY_RCVD, NBR_ACT_CLR_LST, NBR_STA_INIT}, {-1, NBR_EVT_NOTHING, NBR_ACT_NOTHING, 0}, }; const char * const nbr_event_names[] = { "NOTHING", "HELLO_RECEIVED", "2_WAY_RECEIVED", "NEGOTIATION_DONE", "SNAPSHOT_DONE", "EXCHANGE_DONE", "BAD_LS_REQ", "LOADING_DONE", "ADJ_OK", "SEQ_NUM_MISMATCH", "1_WAY_RECEIVED", "KILL_NBR", "INACTIVITY_TIMER", "LL_DOWN", "ADJ_TIMEOUT" }; const char * const nbr_action_names[] = { "NOTHING", "RESET_INACTIVITY_TIMER", "START_INACTIVITY_TIMER", "EVAL", "SNAPSHOT", "SNAPSHOT_DONE", "EXCHANGE_DONE", "ADJ_OK", "RESET_DD", "DELETE", "CLEAR_LISTS", "HELLO_CHK" }; int nbr_fsm(struct nbr *nbr, enum nbr_event event) { struct timeval now; int old_state; int new_state = 0; int i, ret = 0; if (nbr == nbr->iface->self) return (0); old_state = nbr->state; for (i = 0; nbr_fsm_tbl[i].state != -1; i++) if ((nbr_fsm_tbl[i].state & old_state) && (nbr_fsm_tbl[i].event == event)) { new_state = nbr_fsm_tbl[i].new_state; break; } if (nbr_fsm_tbl[i].state == -1) { /* event outside of the defined fsm, ignore it. */ log_warnx("nbr_fsm: neighbor ID %s (%s), " "event %s not expected in state %s", inet_ntoa(nbr->id), nbr->iface->name, nbr_event_names[event], nbr_state_name(old_state)); return (0); } switch (nbr_fsm_tbl[i].action) { case NBR_ACT_RST_ITIMER: ret = nbr_act_reset_itimer(nbr); break; case NBR_ACT_STRT_ITIMER: ret = nbr_act_start_itimer(nbr); break; case NBR_ACT_EVAL: ret = nbr_act_eval(nbr); break; case NBR_ACT_SNAP: ret = nbr_act_snapshot(nbr); break; case NBR_ACT_SNAP_DONE: /* start db exchange */ start_db_tx_timer(nbr); break; case NBR_ACT_XCHNG_DONE: ret = nbr_act_exchange_done(nbr); break; case NBR_ACT_ADJ_OK: ret = nbr_act_adj_ok(nbr); break; case NBR_ACT_RESTRT_DD: ret = nbr_act_restart_dd(nbr); break; case NBR_ACT_DEL: ret = nbr_act_delete(nbr); break; case NBR_ACT_CLR_LST: ret = nbr_act_clear_lists(nbr); break; case NBR_ACT_HELLO_CHK: ret = nbr_act_hello_check(nbr); break; case NBR_ACT_NOTHING: /* do nothing */ break; } if (ret) { log_warnx("nbr_fsm: error changing state for neighbor " "ID %s (%s), event %s, state %s", inet_ntoa(nbr->id), nbr->iface->name, nbr_event_names[event], nbr_state_name(old_state)); return (-1); } if (new_state != 0) nbr->state = new_state; if (old_state != nbr->state) { nbr->stats.sta_chng++; /* state change inform RDE */ ospfe_imsg_compose_rde(IMSG_NEIGHBOR_CHANGE, nbr->peerid, 0, &nbr->state, sizeof(nbr->state)); if (old_state & NBR_STA_FULL || nbr->state & NBR_STA_FULL) { /* * neighbor changed from/to FULL * originate new rtr and net LSA */ orig_rtr_lsa(nbr->iface->area); if (nbr->iface->state & IF_STA_DR) orig_net_lsa(nbr->iface); gettimeofday(&now, NULL); nbr->uptime = now.tv_sec; } /* bidirectional communication lost */ if (old_state & ~NBR_STA_PRELIM && nbr->state & NBR_STA_PRELIM) if_fsm(nbr->iface, IF_EVT_NBR_CHNG); log_debug("nbr_fsm: event %s resulted in action %s and " "changing state for neighbor ID %s (%s) from %s to %s", nbr_event_names[event], nbr_action_names[nbr_fsm_tbl[i].action], inet_ntoa(nbr->id), nbr->iface->name, nbr_state_name(old_state), nbr_state_name(nbr->state)); if (nbr->iface->type == IF_TYPE_VIRTUALLINK) { orig_rtr_lsa(nbr->iface->area); } } return (ret); } void nbr_init(u_int32_t hashsize) { struct nbr_head *head; struct nbr *nbr; u_int32_t hs, i; for (hs = 1; hs < hashsize; hs <<= 1) ; nbrtable.hashtbl = calloc(hs, sizeof(struct nbr_head)); if (nbrtable.hashtbl == NULL) fatal("nbr_init"); for (i = 0; i < hs; i++) LIST_INIT(&nbrtable.hashtbl[i]); nbrtable.hashmask = hs - 1; /* allocate a dummy neighbor used for self originated AS ext routes */ if ((nbr = calloc(1, sizeof(*nbr))) == NULL) fatal("nbr_init"); nbr->id.s_addr = ospfe_router_id(); nbr->state = NBR_STA_DOWN; nbr->peerid = NBR_IDSELF; head = NBR_HASH(nbr->peerid); LIST_INSERT_HEAD(head, nbr, hash); TAILQ_INIT(&nbr->ls_retrans_list); TAILQ_INIT(&nbr->db_sum_list); TAILQ_INIT(&nbr->ls_req_list); } struct nbr * nbr_new(u_int32_t nbr_id, struct iface *iface, int self) { struct nbr_head *head; struct nbr *nbr; struct rde_nbr rn; if ((nbr = calloc(1, sizeof(*nbr))) == NULL) fatal("nbr_new"); nbr->state = NBR_STA_DOWN; nbr->dd_master = 1; nbr->dd_seq_num = arc4random(); /* RFC: some unique value */ nbr->id.s_addr = nbr_id; /* get next unused peerid */ while (nbr_find_peerid(++peercnt)) ; nbr->peerid = peercnt; head = NBR_HASH(nbr->peerid); LIST_INSERT_HEAD(head, nbr, hash); /* add to peer list */ nbr->iface = iface; LIST_INSERT_HEAD(&iface->nbr_list, nbr, entry); TAILQ_INIT(&nbr->ls_retrans_list); TAILQ_INIT(&nbr->db_sum_list); TAILQ_INIT(&nbr->ls_req_list); nbr->ls_req = NULL; if (self) { nbr->state = NBR_STA_FULL; nbr->addr.s_addr = iface->addr.s_addr; nbr->priority = iface->priority; } /* set event structures */ evtimer_set(&nbr->inactivity_timer, nbr_itimer, nbr); evtimer_set(&nbr->db_tx_timer, db_tx_timer, nbr); evtimer_set(&nbr->lsreq_tx_timer, ls_req_tx_timer, nbr); evtimer_set(&nbr->ls_retrans_timer, ls_retrans_timer, nbr); evtimer_set(&nbr->adj_timer, nbr_adj_timer, nbr); bzero(&rn, sizeof(rn)); rn.id.s_addr = nbr->id.s_addr; rn.area_id.s_addr = nbr->iface->area->id.s_addr; rn.addr.s_addr = nbr->addr.s_addr; rn.ifindex = nbr->iface->ifindex; rn.state = nbr->state; rn.self = self; ospfe_imsg_compose_rde(IMSG_NEIGHBOR_UP, nbr->peerid, 0, &rn, sizeof(rn)); return (nbr); } void nbr_del(struct nbr *nbr) { ospfe_imsg_compose_rde(IMSG_NEIGHBOR_DOWN, nbr->peerid, 0, NULL, 0); if (evtimer_pending(&nbr->inactivity_timer, NULL)) evtimer_del(&nbr->inactivity_timer); if (evtimer_pending(&nbr->db_tx_timer, NULL)) evtimer_del(&nbr->db_tx_timer); if (evtimer_pending(&nbr->lsreq_tx_timer, NULL)) evtimer_del(&nbr->lsreq_tx_timer); if (evtimer_pending(&nbr->ls_retrans_timer, NULL)) evtimer_del(&nbr->ls_retrans_timer); if (evtimer_pending(&nbr->adj_timer, NULL)) evtimer_del(&nbr->adj_timer); /* clear lists */ ls_retrans_list_clr(nbr); db_sum_list_clr(nbr); ls_req_list_clr(nbr); if (nbr->peerid != NBR_IDSELF) LIST_REMOVE(nbr, entry); LIST_REMOVE(nbr, hash); free(nbr); } struct nbr * nbr_find_peerid(u_int32_t peerid) { struct nbr_head *head; struct nbr *nbr; head = NBR_HASH(peerid); LIST_FOREACH(nbr, head, hash) { if (nbr->peerid == peerid) return (nbr); } return (NULL); } struct nbr * nbr_find_id(struct iface *iface, u_int32_t rtr_id) { struct nbr *nbr = NULL; LIST_FOREACH(nbr, &iface->nbr_list, entry) { if (nbr->id.s_addr == rtr_id) return (nbr); } return (NULL); } /* timers */ /* ARGSUSED */ void nbr_itimer(int fd, short event, void *arg) { struct nbr *nbr = arg; if (nbr->state == NBR_STA_DOWN) nbr_del(nbr); else nbr_fsm(nbr, NBR_EVT_ITIMER); } void nbr_start_itimer(struct nbr *nbr) { struct timeval tv; timerclear(&tv); tv.tv_sec = nbr->iface->dead_interval; if (evtimer_add(&nbr->inactivity_timer, &tv) == -1) fatal("nbr_start_itimer"); } void nbr_stop_itimer(struct nbr *nbr) { if (evtimer_del(&nbr->inactivity_timer) == -1) fatal("nbr_stop_itimer"); } void nbr_reset_itimer(struct nbr *nbr) { struct timeval tv; timerclear(&tv); tv.tv_sec = nbr->iface->dead_interval; if (evtimer_add(&nbr->inactivity_timer, &tv) == -1) fatal("nbr_reset_itimer"); } /* ARGSUSED */ void nbr_adj_timer(int fd, short event, void *arg) { struct nbr *nbr = arg; if (!(nbr->state & NBR_STA_ADJFORM)) return; if (nbr->state & NBR_STA_ACTIVE && nbr->state != NBR_STA_FULL) { log_warnx("nbr_adj_timer: failed to form adjacency with %s " "on interface %s", inet_ntoa(nbr->id), nbr->iface->name); nbr_fsm(nbr, NBR_EVT_ADJTMOUT); } } void nbr_start_adj_timer(struct nbr *nbr) { struct timeval tv; timerclear(&tv); tv.tv_sec = DEFAULT_ADJ_TMOUT; if (evtimer_add(&nbr->adj_timer, &tv) == -1) fatal("nbr_start_adj_timer"); } /* actions */ int nbr_act_reset_itimer(struct nbr *nbr) { nbr_reset_itimer(nbr); return (0); } int nbr_act_start_itimer(struct nbr *nbr) { nbr_start_itimer(nbr); return (0); } int nbr_adj_ok(struct nbr *nbr) { struct iface *iface = nbr->iface; switch (iface->type) { case IF_TYPE_POINTOPOINT: case IF_TYPE_VIRTUALLINK: case IF_TYPE_POINTOMULTIPOINT: /* always ok */ break; case IF_TYPE_BROADCAST: case IF_TYPE_NBMA: /* * if neighbor is dr, bdr or router self is dr or bdr * start forming adjacency */ if (iface->dr == nbr || iface->bdr == nbr || iface->state & IF_STA_DRORBDR) break; return (0); default: fatalx("nbr_adj_ok: unknown interface type"); } return (1); } int nbr_act_eval(struct nbr *nbr) { if (!nbr_adj_ok(nbr)) { nbr->state = NBR_STA_2_WAY; return (0); } nbr->state = NBR_STA_XSTRT; nbr->dd_master = 1; nbr->dd_seq_num++; /* as per RFC */ nbr->dd_pending = 0; /* initial db negotiation */ start_db_tx_timer(nbr); nbr_start_adj_timer(nbr); return (0); } int nbr_act_snapshot(struct nbr *nbr) { stop_db_tx_timer(nbr); /* we need to wait for the old snapshot to finish */ if (nbr->dd_snapshot) { log_debug("nbr_act_snapshot: giving up, old snapshot running " "for neighbor ID %s (%s)", inet_ntoa(nbr->id), nbr->iface->name); return (nbr_act_restart_dd(nbr)); } ospfe_imsg_compose_rde(IMSG_NEIGHBOR_CAPA, nbr->peerid, 0, &nbr->capa_options, sizeof(nbr->capa_options)); ospfe_imsg_compose_rde(IMSG_DB_SNAPSHOT, nbr->peerid, 0, NULL, 0); nbr->dd_snapshot = 1; /* wait for IMSG_DB_END */ nbr->state = NBR_STA_SNAP; return (0); } int nbr_act_exchange_done(struct nbr *nbr) { if (nbr->dd_master) stop_db_tx_timer(nbr); if (ls_req_list_empty(nbr) && nbr->state == NBR_STA_XCHNG && nbr->dd_pending == 0) { nbr->state = NBR_STA_FULL; return (0); } nbr->state = NBR_STA_LOAD; if (!ls_req_list_empty(nbr)) start_ls_req_tx_timer(nbr); return (0); } int nbr_act_adj_ok(struct nbr *nbr) { if (nbr_adj_ok(nbr)) { if (nbr->state == NBR_STA_2_WAY) return (nbr_act_eval(nbr)); } else { nbr->state = NBR_STA_2_WAY; return (nbr_act_clear_lists(nbr)); } return (0); } int nbr_act_restart_dd(struct nbr *nbr) { nbr_act_clear_lists(nbr); if (!nbr_adj_ok(nbr)) { nbr->state = NBR_STA_2_WAY; return (0); } nbr->state = NBR_STA_XSTRT; nbr->dd_master = 1; nbr->dd_seq_num += arc4random() & 0xffff; nbr->dd_pending = 0; /* initial db negotiation */ start_db_tx_timer(nbr); nbr_start_adj_timer(nbr); return (0); } int nbr_act_delete(struct nbr *nbr) { struct timeval tv; /* clear dr and bdr */ nbr->dr.s_addr = 0; nbr->bdr.s_addr = 0; if (nbr == nbr->iface->self) return (0); /* stop timers */ nbr_stop_itimer(nbr); /* XXX reset crypt_seq_num will allow replay attacks. */ nbr->crypt_seq_num = 0; /* schedule kill timer */ timerclear(&tv); tv.tv_sec = DEFAULT_NBR_TMOUT; if (evtimer_add(&nbr->inactivity_timer, &tv)) { log_warnx("nbr_act_delete: error scheduling " "neighbor ID %s (%s) for removal", inet_ntoa(nbr->id), nbr->iface->name); } return (nbr_act_clear_lists(nbr)); } int nbr_act_clear_lists(struct nbr *nbr) { /* stop timers */ stop_db_tx_timer(nbr); stop_ls_req_tx_timer(nbr); /* clear lists */ ls_retrans_list_clr(nbr); db_sum_list_clr(nbr); ls_req_list_clr(nbr); return (0); } int nbr_act_hello_check(struct nbr *nbr) { log_debug("nbr_act_hello_check: neighbor ID %s (%s)", inet_ntoa(nbr->id), nbr->iface->name); return (-1); } struct ctl_nbr * nbr_to_ctl(struct nbr *nbr) { static struct ctl_nbr nctl; struct timeval tv, now, res; struct lsa_entry *le; memcpy(nctl.name, nbr->iface->name, sizeof(nctl.name)); memcpy(&nctl.id, &nbr->id, sizeof(nctl.id)); memcpy(&nctl.addr, &nbr->addr, sizeof(nctl.addr)); memcpy(&nctl.dr, &nbr->dr, sizeof(nctl.dr)); memcpy(&nctl.bdr, &nbr->bdr, sizeof(nctl.bdr)); memcpy(&nctl.area, &nbr->iface->area->id, sizeof(nctl.area)); /* this list is 99% of the time empty so that's OK for now */ nctl.db_sum_lst_cnt = 0; TAILQ_FOREACH(le, &nbr->db_sum_list, entry) nctl.db_sum_lst_cnt++; nctl.ls_req_lst_cnt = nbr->ls_req_cnt; nctl.ls_retrans_lst_cnt = nbr->ls_ret_cnt; nctl.nbr_state = nbr->state; /* * We need to trick a bit to show the remote iface state. * The idea is to print DR, BDR or DROther dependent on * the type of the neighbor. */ if (nbr->iface->dr == nbr) nctl.iface_state = IF_STA_DR; else if (nbr->iface->bdr == nbr) nctl.iface_state = IF_STA_BACKUP; else if (nbr->iface->state & IF_STA_MULTI) nctl.iface_state = IF_STA_DROTHER; else nctl.iface_state = nbr->iface->state; nctl.state_chng_cnt = nbr->stats.sta_chng; nctl.priority = nbr->priority; nctl.options = nbr->options | nbr->capa_options; gettimeofday(&now, NULL); if (evtimer_pending(&nbr->inactivity_timer, &tv)) { timersub(&tv, &now, &res); if (nbr->state & NBR_STA_DOWN) nctl.dead_timer = DEFAULT_NBR_TMOUT - res.tv_sec; else nctl.dead_timer = res.tv_sec; } else nctl.dead_timer = 0; if (nbr->state == NBR_STA_FULL) { nctl.uptime = now.tv_sec - nbr->uptime; } else nctl.uptime = 0; return (&nctl); } struct lsa_hdr * lsa_hdr_new(void) { struct lsa_hdr *lsa_hdr = NULL; if ((lsa_hdr = calloc(1, sizeof(*lsa_hdr))) == NULL) fatal("lsa_hdr_new"); return (lsa_hdr); }