/* * The mrouted program is covered by the license in the accompanying file * named "LICENSE". Use of the mrouted program represents acceptance of * the terms and conditions listed in that file. * * The mrouted program is COPYRIGHT 1989 by The Board of Trustees of * Leland Stanford Junior University. * * * route.c,v 3.8.4.41 1998/01/15 00:08:34 fenner Exp * * $FreeBSD: src/usr.sbin/mrouted/route.c,v 1.12 1999/08/28 01:17:08 peter Exp $ * $DragonFly: src/usr.sbin/mrouted/route.c,v 1.4 2004/03/15 18:10:28 dillon Exp $ */ #include "defs.h" /* * This define statement saves a lot of space later */ #define RT_ADDR (struct rtentry *)&routing_table /* * Exported variables. */ int routes_changed; /* 1=>some routes have changed */ int delay_change_reports; /* 1=>postpone change reports */ /* * The routing table is shared with prune.c , so must not be static. */ struct rtentry *routing_table; /* pointer to list of route entries */ /* * Private variables. */ static struct rtentry *rtp; /* pointer to a route entry */ static struct rtentry *rt_end; /* pointer to last route entry */ unsigned int nroutes; /* current number of route entries */ /* * Private functions. */ static int init_children_and_leaves(struct rtentry *r, vifi_t parent, int first); static int find_route (u_int32 origin, u_int32 mask); static void create_route(u_int32 origin, u_int32 mask); static void discard_route(struct rtentry *prev_r); static int compare_rts (const void *rt1, const void *rt2); static int report_chunk (int, struct rtentry *start_rt, vifi_t vifi, u_int32 dst); static void queue_blaster_report(vifi_t, u_int32, u_int32, char *, int, u_int32); static void process_blaster_report(void *); #ifdef SNMP #include #include "snmp.h" /* * Return pointer to a specific route entry. This must be a separate * function from find_route() which modifies rtp. */ struct rtentry * snmp_find_route(u_int32 src, u_int32 mask) { struct rtentry *rt; for (rt = routing_table; rt; rt = rt->rt_next) { if (src == rt->rt_origin && mask == rt->rt_originmask) return rt; } return NULL; } /* * Find next route entry > specification */ int next_route(struct rtentry **rtpp, u_int32 src, u_int32 mask) { struct rtentry *rt, *rbest = NULL; /* Among all entries > spec, find "lowest" one in order */ for (rt = routing_table; rt; rt=rt->rt_next) { if ((ntohl(rt->rt_origin) > ntohl(src) || (ntohl(rt->rt_origin) == ntohl(src) && ntohl(rt->rt_originmask) > ntohl(mask))) && (!rbest || (ntohl(rt->rt_origin) < ntohl(rbest->rt_origin)) || (ntohl(rt->rt_origin) == ntohl(rbest->rt_origin) && ntohl(rt->rt_originmask) < ntohl(rbest->rt_originmask)))) rbest = rt; } (*rtpp) = rbest; return (*rtpp)!=0; } /* * Given a routing table entry, and a vifi, find the next vifi/entry */ int next_route_child(struct rtentry **rtpp, u_int32 src, u_int32 mask, vifi_t *vifi) { /* Get (S,M) entry */ if (!((*rtpp) = snmp_find_route(src,mask))) if (!next_route(rtpp, src, mask)) return 0; /* Continue until we get one with a valid next vif */ do { for (; (*rtpp)->rt_children && *vifirt_children)) return 1; *vifi = 0; } while( next_route(rtpp, (*rtpp)->rt_origin, (*rtpp)->rt_originmask) ); return 0; } #endif /* * Initialize the routing table and associated variables. */ void init_routes() { routing_table = NULL; rt_end = RT_ADDR; nroutes = 0; routes_changed = FALSE; delay_change_reports = FALSE; } /* * Initialize the children bits for route 'r', along with the * associated dominant and subordinate data structures. * If first is set, initialize dominants, otherwise keep old * dominants on non-parent interfaces. * XXX Does this need a return value? */ static int init_children_and_leaves(struct rtentry *r, vifi_t parent, int first) { vifi_t vifi; struct uvif *v; vifbitmap_t old_children; nbrbitmap_t old_subords; VIFM_COPY(r->rt_children, old_children); NBRM_COPY(r->rt_subordinates, old_subords); VIFM_CLRALL(r->rt_children); for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (first || vifi == parent) r->rt_dominants [vifi] = 0; if (vifi == parent || uvifs[vifi].uv_flags & VIFF_NOFLOOD || AVOID_TRANSIT(vifi, r) || (!first && r->rt_dominants[vifi])) NBRM_CLRMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); else NBRM_SETMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); if (vifi != parent && !(v->uv_flags & (VIFF_DOWN|VIFF_DISABLED)) && !(!first && r->rt_dominants[vifi])) { VIFM_SET(vifi, r->rt_children); } } return (!VIFM_SAME(r->rt_children, old_children) || !NBRM_SAME(r->rt_subordinates, old_subords)); } /* * A new vif has come up -- update the children bitmaps in all route * entries to take that into account. */ void add_vif_to_routes(vifi_t vifi) { struct rtentry *r; struct uvif *v; v = &uvifs[vifi]; for (r = routing_table; r != NULL; r = r->rt_next) { if (r->rt_metric != UNREACHABLE && !VIFM_ISSET(vifi, r->rt_children)) { VIFM_SET(vifi, r->rt_children); r->rt_dominants [vifi] = 0; /*XXX isn't uv_nbrmap going to be empty?*/ NBRM_CLRMASK(r->rt_subordinates, v->uv_nbrmap); update_table_entry(r, r->rt_gateway); } } } /* * A vif has gone down -- expire all routes that have that vif as parent, * and update the children bitmaps in all other route entries to take into * account the failed vif. */ void delete_vif_from_routes(vifi_t vifi) { struct rtentry *r; for (r = routing_table; r != NULL; r = r->rt_next) { if (r->rt_metric != UNREACHABLE) { if (vifi == r->rt_parent) { del_table_entry(r, 0, DEL_ALL_ROUTES); r->rt_timer = ROUTE_EXPIRE_TIME; r->rt_metric = UNREACHABLE; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; } else if (VIFM_ISSET(vifi, r->rt_children)) { VIFM_CLR(vifi, r->rt_children); NBRM_CLRMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); update_table_entry(r, r->rt_gateway); } else { r->rt_dominants[vifi] = 0; } } } } /* * A new neighbor has come up. If we're flooding on the neighbor's * vif, mark that neighbor as subordinate for all routes whose parent * is not this vif. */ void add_neighbor_to_routes(vifi_t vifi, int index) { struct rtentry *r; struct uvif *v; v = &uvifs[vifi]; if (v->uv_flags & VIFF_NOFLOOD) return; for (r = routing_table; r != NULL; r = r->rt_next) { if (r->rt_metric != UNREACHABLE && r->rt_parent != vifi && !AVOID_TRANSIT(vifi, r)) { NBRM_SET(index, r->rt_subordinates); update_table_entry(r, r->rt_gateway); } } } /* * A neighbor has failed or become unreachable. If that neighbor was * considered a dominant or subordinate router in any route entries, * take appropriate action. Expire all routes this neighbor advertised * to us. */ void delete_neighbor_from_routes(u_int32 addr, vifi_t vifi, int index) { struct rtentry *r; struct uvif *v; v = &uvifs[vifi]; for (r = routing_table; r != NULL; r = r->rt_next) { if (r->rt_metric != UNREACHABLE) { if (r->rt_parent == vifi && r->rt_gateway == addr) { del_table_entry(r, 0, DEL_ALL_ROUTES); r->rt_timer = ROUTE_EXPIRE_TIME; r->rt_metric = UNREACHABLE; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; } else if (r->rt_dominants[vifi] == addr) { VIFM_SET(vifi, r->rt_children); r->rt_dominants[vifi] = 0; if ((uvifs[vifi].uv_flags & VIFF_NOFLOOD) || AVOID_TRANSIT(vifi, r)) NBRM_CLRMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); else NBRM_SETMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); update_table_entry(r, r->rt_gateway); } else if (NBRM_ISSET(index, r->rt_subordinates)) { NBRM_CLR(index, r->rt_subordinates); update_table_entry(r, r->rt_gateway); } } } } /* * Prepare for a sequence of ordered route updates by initializing a pointer * to the start of the routing table. The pointer is used to remember our * position in the routing table in order to avoid searching from the * beginning for each update; this relies on having the route reports in * a single message be in the same order as the route entries in the routing * table. */ void start_route_updates(void) { rtp = RT_ADDR; } /* * Starting at the route entry following the one to which 'rtp' points, * look for a route entry matching the specified origin and mask. If a * match is found, return TRUE and leave 'rtp' pointing at the found entry. * If no match is found, return FALSE and leave 'rtp' pointing to the route * entry preceding the point at which the new origin should be inserted. * This code is optimized for the normal case in which the first entry to * be examined is the matching entry. */ static int find_route(u_int32 origin, u_int32 mask) { struct rtentry *r; r = rtp->rt_next; while (r != NULL) { if (origin == r->rt_origin && mask == r->rt_originmask) { rtp = r; return (TRUE); } if (ntohl(mask) < ntohl(r->rt_originmask) || (mask == r->rt_originmask && ntohl(origin) < ntohl(r->rt_origin))) { rtp = r; r = r->rt_next; } else break; } return (FALSE); } /* * Create a new routing table entry for the specified origin and link it into * the routing table. The shared variable 'rtp' is assumed to point to the * routing entry after which the new one should be inserted. It is left * pointing to the new entry. * * Only the origin, originmask, originwidth and flags fields are initialized * in the new route entry; the caller is responsible for filling in the the * rest. */ static void create_route(u_int32 origin, u_int32 mask) { struct rtentry *r; if ((r = (struct rtentry *) malloc(sizeof(struct rtentry) + (numvifs * sizeof(u_int32)))) == NULL) { log(LOG_ERR, 0, "ran out of memory"); /* fatal */ } r->rt_origin = origin; r->rt_originmask = mask; if (((char *)&mask)[3] != 0) r->rt_originwidth = 4; else if (((char *)&mask)[2] != 0) r->rt_originwidth = 3; else if (((char *)&mask)[1] != 0) r->rt_originwidth = 2; else r->rt_originwidth = 1; r->rt_flags = 0; r->rt_dominants = (u_int32 *)(r + 1); bzero(r->rt_dominants, numvifs * sizeof(u_int32)); r->rt_groups = NULL; VIFM_CLRALL(r->rt_children); NBRM_CLRALL(r->rt_subordinates); NBRM_CLRALL(r->rt_subordadv); r->rt_next = rtp->rt_next; rtp->rt_next = r; r->rt_prev = rtp; if (r->rt_next != NULL) (r->rt_next)->rt_prev = r; else rt_end = r; rtp = r; ++nroutes; } /* * Discard the routing table entry following the one to which 'prev_r' points. */ static void discard_route(struct rtentry *prev_r) { struct rtentry *r; r = prev_r->rt_next; uvifs[r->rt_parent].uv_nroutes--; /*???nbr???.al_nroutes--;*/ prev_r->rt_next = r->rt_next; if (prev_r->rt_next != NULL) (prev_r->rt_next)->rt_prev = prev_r; else rt_end = prev_r; free((char *)r); --nroutes; } /* * Process a route report for a single origin, creating or updating the * corresponding routing table entry if necessary. 'src' is either the * address of a neighboring router from which the report arrived, or zero * to indicate a change of status of one of our own interfaces. */ void update_route(u_int32 origin, u_int32 mask, u_int metric, u_int32 src, vifi_t vifi, struct listaddr *n) { struct rtentry *r; u_int adj_metric; /* * Compute an adjusted metric, taking into account the cost of the * subnet or tunnel over which the report arrived, and normalizing * all unreachable/poisoned metrics into a single value. */ if (src != 0 && (metric < 1 || metric >= 2*UNREACHABLE)) { log(LOG_WARNING, 0, "%s reports out-of-range metric %u for origin %s", inet_fmt(src, s1), metric, inet_fmts(origin, mask, s2)); return; } adj_metric = metric + uvifs[vifi].uv_metric; if (adj_metric > UNREACHABLE) adj_metric = UNREACHABLE; /* * Look up the reported origin in the routing table. */ if (!find_route(origin, mask)) { /* * Not found. * Don't create a new entry if the report says it's unreachable, * or if the reported origin and mask are invalid. */ if (adj_metric == UNREACHABLE) { return; } if (src != 0 && !inet_valid_subnet(origin, mask)) { log(LOG_WARNING, 0, "%s reports an invalid origin (%s) and/or mask (%08x)", inet_fmt(src, s1), inet_fmt(origin, s2), ntohl(mask)); return; } IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s advertises new route %s", inet_fmt(src, s1), inet_fmts(origin, mask, s2)); /* * OK, create the new routing entry. 'rtp' will be left pointing * to the new entry. */ create_route(origin, mask); uvifs[vifi].uv_nroutes++; /*n->al_nroutes++;*/ rtp->rt_metric = UNREACHABLE; /* temporary; updated below */ } /* * We now have a routing entry for the reported origin. Update it? */ r = rtp; if (r->rt_metric == UNREACHABLE) { /* * The routing entry is for a formerly-unreachable or new origin. * If the report claims reachability, update the entry to use * the reported route. */ if (adj_metric == UNREACHABLE) return; IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s advertises %s with adj_metric %d (ours was %d)", inet_fmt(src, s1), inet_fmts(origin, mask, s2), adj_metric, r->rt_metric); /* * Now "steal away" any sources that belong under this route * by deleting any cache entries they might have created * and allowing the kernel to re-request them. * * If we haven't performed final initialization yet and are * just collecting the routing table, we can't have any * sources so we don't perform this step. */ if (did_final_init) steal_sources(rtp); r->rt_parent = vifi; r->rt_gateway = src; init_children_and_leaves(r, vifi, 1); r->rt_timer = 0; r->rt_metric = adj_metric; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; update_table_entry(r, r->rt_gateway); } else if (src == r->rt_gateway) { /* * The report has come either from the interface directly-connected * to the origin subnet (src and r->rt_gateway both equal zero) or * from the gateway we have chosen as the best first-hop gateway back * towards the origin (src and r->rt_gateway not equal zero). Reset * the route timer and, if the reported metric has changed, update * our entry accordingly. */ r->rt_timer = 0; IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s (current parent) advertises %s with adj_metric %d (ours was %d)", inet_fmt(src, s1), inet_fmts(origin, mask, s2), adj_metric, r->rt_metric); if (adj_metric == r->rt_metric) return; if (adj_metric == UNREACHABLE) { del_table_entry(r, 0, DEL_ALL_ROUTES); r->rt_timer = ROUTE_EXPIRE_TIME; } r->rt_metric = adj_metric; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; } else if (src == 0 || (r->rt_gateway != 0 && (adj_metric < r->rt_metric || (adj_metric == r->rt_metric && (ntohl(src) < ntohl(r->rt_gateway) || r->rt_timer >= ROUTE_SWITCH_TIME))))) { /* * The report is for an origin we consider reachable; the report * comes either from one of our own interfaces or from a gateway * other than the one we have chosen as the best first-hop gateway * back towards the origin. If the source of the update is one of * our own interfaces, or if the origin is not a directly-connected * subnet and the reported metric for that origin is better than * what our routing entry says, update the entry to use the new * gateway and metric. We also switch gateways if the reported * metric is the same as the one in the route entry and the gateway * associated with the route entry has not been heard from recently, * or if the metric is the same but the reporting gateway has a lower * IP address than the gateway associated with the route entry. * Did you get all that? */ u_int32 old_gateway; vifi_t old_parent; old_gateway = r->rt_gateway; old_parent = r->rt_parent; r->rt_gateway = src; r->rt_parent = vifi; IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s (new parent) on vif %d advertises %s with adj_metric %d (old parent was %s on vif %d, metric %d)", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), adj_metric, inet_fmt(old_gateway, s3), old_parent, r->rt_metric); if (old_parent != vifi) { init_children_and_leaves(r, vifi, 0); uvifs[old_parent].uv_nroutes--; uvifs[vifi].uv_nroutes++; } if (old_gateway != src) { update_table_entry(r, old_gateway); /*???old_gateway???->al_nroutes--;*/ /*n->al_nroutes++;*/ } r->rt_timer = 0; r->rt_metric = adj_metric; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; } else if (vifi != r->rt_parent) { /* * The report came from a vif other than the route's parent vif. * Update the children info, if necessary. */ if (AVOID_TRANSIT(vifi, r)) { /* * The route's parent is a vif from which we're not supposed * to transit onto this vif. Simply ignore the update. */ IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s on vif %d advertises %s with metric %d (ignored due to NOTRANSIT)", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric); } else if (VIFM_ISSET(vifi, r->rt_children)) { /* * Vif is a child vif for this route. */ if (metric < r->rt_metric || (metric == r->rt_metric && ntohl(src) < ntohl(uvifs[vifi].uv_lcl_addr))) { /* * Neighbor has lower metric to origin (or has same metric * and lower IP address) -- it becomes the dominant router, * and vif is no longer a child for me. */ VIFM_CLR(vifi, r->rt_children); r->rt_dominants [vifi] = src; /* XXX * We don't necessarily want to forget about subordinateness * so that we can become the dominant quickly if the current * dominant fails. */ NBRM_CLRMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); update_table_entry(r, r->rt_gateway); IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s on vif %d becomes dominant for %s with metric %d", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric); } else if (metric > UNREACHABLE) { /* "poisoned reverse" */ /* * Neighbor considers this vif to be on path to route's * origin; record this neighbor as subordinate */ if (!NBRM_ISSET(n->al_index, r->rt_subordinates)) { IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s on vif %d becomes subordinate for %s with poison-reverse metric %d", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric - UNREACHABLE); NBRM_SET(n->al_index, r->rt_subordinates); update_table_entry(r, r->rt_gateway); } else { IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s on vif %d confirms subordinateness for %s with poison-reverse metric %d", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric - UNREACHABLE); } NBRM_SET(n->al_index, r->rt_subordadv); } else if (NBRM_ISSET(n->al_index, r->rt_subordinates)) { /* * Current subordinate no longer considers this vif to be on * path to route's origin; it is no longer a subordinate * router. */ IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s on vif %d is no longer a subordinate for %s with metric %d", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric); NBRM_CLR(n->al_index, r->rt_subordinates); update_table_entry(r, r->rt_gateway); } } else if (src == r->rt_dominants[vifi] && (metric > r->rt_metric || (metric == r->rt_metric && ntohl(src) > ntohl(uvifs[vifi].uv_lcl_addr)))) { /* * Current dominant no longer has a lower metric to origin * (or same metric and lower IP address); we adopt the vif * as our own child. */ IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s (current dominant) on vif %d is no longer dominant for %s with metric %d", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric); VIFM_SET(vifi, r->rt_children); r->rt_dominants[vifi] = 0; if (uvifs[vifi].uv_flags & VIFF_NOFLOOD) NBRM_CLRMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); else NBRM_SETMASK(r->rt_subordinates, uvifs[vifi].uv_nbrmap); if (metric > UNREACHABLE) { NBRM_SET(n->al_index, r->rt_subordinates); NBRM_SET(n->al_index, r->rt_subordadv); } update_table_entry(r, r->rt_gateway); } else { IF_DEBUG(DEBUG_RTDETAIL) log(LOG_DEBUG, 0, "%s on vif %d advertises %s with metric %d (ignored)", inet_fmt(src, s1), vifi, inet_fmts(origin, mask, s2), metric); } } } /* * On every timer interrupt, advance the timer in each routing entry. */ void age_routes(void) { struct rtentry *r; struct rtentry *prev_r; extern u_long virtual_time; /* from main.c */ for (prev_r = RT_ADDR, r = routing_table; r != NULL; prev_r = r, r = r->rt_next) { if ((r->rt_timer += TIMER_INTERVAL) >= ROUTE_DISCARD_TIME) { /* * Time to garbage-collect the route entry. */ del_table_entry(r, 0, DEL_ALL_ROUTES); discard_route(prev_r); r = prev_r; } else if (r->rt_timer >= ROUTE_EXPIRE_TIME && r->rt_metric != UNREACHABLE) { /* * Time to expire the route entry. If the gateway is zero, * i.e., it is a route to a directly-connected subnet, just * set the timer back to zero; such routes expire only when * the interface to the subnet goes down. */ if (r->rt_gateway == 0) { r->rt_timer = 0; } else { del_table_entry(r, 0, DEL_ALL_ROUTES); r->rt_metric = UNREACHABLE; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; } } else if (virtual_time % (ROUTE_REPORT_INTERVAL * 2) == 0) { /* * Time out subordinateness that hasn't been reported in * the last 2 intervals. */ if (!NBRM_SAME(r->rt_subordinates, r->rt_subordadv)) { IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "rt %s sub 0x%08x%08x subadv 0x%08x%08x metric %d", RT_FMT(r, s1), r->rt_subordinates.hi, r->rt_subordinates.lo, r->rt_subordadv.hi, r->rt_subordadv.lo, r->rt_metric); NBRM_MASK(r->rt_subordinates, r->rt_subordadv); update_table_entry(r, r->rt_gateway); } NBRM_CLRALL(r->rt_subordadv); } } } /* * Mark all routes as unreachable. This function is called only from * hup() in preparation for informing all neighbors that we are going * off the air. For consistency, we ought also to delete all reachable * route entries from the kernel, but since we are about to exit we rely * on the kernel to do its own cleanup -- no point in making all those * expensive kernel calls now. */ void expire_all_routes(void) { struct rtentry *r; for (r = routing_table; r != NULL; r = r->rt_next) { r->rt_metric = UNREACHABLE; r->rt_flags |= RTF_CHANGED; routes_changed = TRUE; } } /* * Delete all the routes in the routing table. */ void free_all_routes(void) { struct rtentry *r; r = RT_ADDR; while (r->rt_next) discard_route(r); } /* * Process an incoming neighbor probe message. */ void accept_probe(u_int32 src, u_int32 dst, char *p, int datalen, u_int32 level) { vifi_t vifi; static struct listaddr *unknowns = NULL; if ((vifi = find_vif(src, dst)) == NO_VIF) { struct listaddr *a, **prev; struct listaddr *match = NULL; time_t now = time(0); for (prev = &unknowns, a = *prev; a; a = *prev) { if (a->al_addr == src) match = a; if (a->al_ctime + 2 * a->al_timer < now) { /* We haven't heard from it in a long time */ *prev = a->al_next; free(a); } else { prev = &a->al_next; } } if (match == NULL) { match = *prev = (struct listaddr *)malloc(sizeof(struct listaddr)); match->al_next = NULL; match->al_addr = src; match->al_timer = OLD_NEIGHBOR_EXPIRE_TIME; match->al_ctime = now - match->al_timer; } if (match->al_ctime + match->al_timer <= now) { log(LOG_WARNING, 0, "ignoring probe from non-neighbor %s, check for misconfigured tunnel or routing on %s", inet_fmt(src, s1), s1); match->al_timer *= 2; } else IF_DEBUG(DEBUG_PEER) log(LOG_DEBUG, 0, "ignoring probe from non-neighbor %s (%d seconds until next warning)", inet_fmt(src, s1), match->al_ctime + match->al_timer - now); return; } update_neighbor(vifi, src, DVMRP_PROBE, p, datalen, level); } struct newrt { u_int32 mask; u_int32 origin; int metric; int pad; }; static int compare_rts(const void *rt1, const void *rt2) { struct newrt *r1 = (struct newrt *)rt1; struct newrt *r2 = (struct newrt *)rt2; u_int32 m1 = ntohl(r1->mask); u_int32 m2 = ntohl(r2->mask); u_int32 o1, o2; if (m1 > m2) return (-1); if (m1 < m2) return (1); /* masks are equal */ o1 = ntohl(r1->origin); o2 = ntohl(r2->origin); if (o1 > o2) return (-1); if (o1 < o2) return (1); return (0); } void blaster_alloc(vifi_t vifi) { struct uvif *v; v = &uvifs[vifi]; if (v->uv_blasterbuf) free(v->uv_blasterbuf); v->uv_blasterlen = 64*1024; v->uv_blasterbuf = malloc(v->uv_blasterlen); v->uv_blastercur = v->uv_blasterend = v->uv_blasterbuf; if (v->uv_blastertimer) timer_clearTimer(v->uv_blastertimer); v->uv_blastertimer = 0; } struct blaster_hdr { u_int32 bh_src; u_int32 bh_dst; u_int32 bh_level; int bh_datalen; }; /* * Queue a route report from a route-blaster. * If the timer isn't running to process these reports, * start it. */ static void queue_blaster_report(vifi_t vifi, u_int32 src, u_int32 dst, char *p, int datalen, u_int32 level) { struct blaster_hdr *bh; struct uvif *v; int bblen = sizeof(*bh) + ((datalen + 3) & ~3); v = &uvifs[vifi]; if (v->uv_blasterend - v->uv_blasterbuf + bblen > v->uv_blasterlen) { int end = v->uv_blasterend - v->uv_blasterbuf; int cur = v->uv_blastercur - v->uv_blasterbuf; v->uv_blasterlen *= 2; IF_DEBUG(DEBUG_IF) log(LOG_DEBUG, 0, "increasing blasterbuf to %d bytes", v->uv_blasterlen); v->uv_blasterbuf = realloc(v->uv_blasterbuf, v->uv_blasterlen); if (v->uv_blasterbuf == NULL) { log(LOG_WARNING, ENOMEM, "turning off blaster on vif %d", vifi); v->uv_blasterlen = 0; v->uv_blasterend = v->uv_blastercur = NULL; v->uv_flags &= ~VIFF_BLASTER; return; } v->uv_blasterend = v->uv_blasterbuf + end; v->uv_blastercur = v->uv_blasterbuf + cur; } bh = (struct blaster_hdr *)v->uv_blasterend; bh->bh_src = src; bh->bh_dst = dst; bh->bh_level = level; bh->bh_datalen = datalen; bcopy(p, (char *)(bh + 1), datalen); v->uv_blasterend += bblen; if (v->uv_blastertimer == 0) { int *i = (int *)malloc(sizeof(int *)); if (i == NULL) log(LOG_ERR, 0, "out of memory"); *i = vifi; v->uv_blastertimer = timer_setTimer(5, process_blaster_report, i); } } /* * Periodic process; process up to 5 of the routes in the route-blaster * queue. If there are more routes remaining, reschedule myself to run * in 1 second. */ static void process_blaster_report(void *vifip) { vifi_t vifi = *(int *)vifip; struct uvif *v; struct blaster_hdr *bh; int i; IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "processing vif %d blasted routes", vifi); v = &uvifs[vifi]; for (i = 0; i < 5; i++) { if (v->uv_blastercur >= v->uv_blasterend) break; bh = (struct blaster_hdr *)v->uv_blastercur; v->uv_blastercur += sizeof(*bh) + ((bh->bh_datalen + 3) & ~3); accept_report(bh->bh_src, bh->bh_dst, (char *)(bh + 1), -bh->bh_datalen, bh->bh_level); } if (v->uv_blastercur >= v->uv_blasterend) { v->uv_blastercur = v->uv_blasterbuf; v->uv_blasterend = v->uv_blasterbuf; v->uv_blastertimer = 0; free(vifip); IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "finish processing vif %d blaster", vifi); } else { IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "more blasted routes to come on vif %d", vifi); v->uv_blastertimer = timer_setTimer(1, process_blaster_report, vifip); } } /* * Process an incoming route report message. * If the report arrived on a vif marked as a "blaster", then just * queue it and return; queue_blaster_report() will schedule it for * processing later. If datalen is negative, then this is actually * a queued report so actually process it instead of queueing it. */ void accept_report(u_int32 src, u_int32 dst, char *p, int datalen, u_int32 level) { vifi_t vifi; int width, i, nrt = 0; int metric; u_int32 mask; u_int32 origin; struct newrt rt[4096]; struct listaddr *nbr; if ((vifi = find_vif(src, dst)) == NO_VIF) { log(LOG_INFO, 0, "ignoring route report from non-neighbor %s", inet_fmt(src, s1)); return; } if (uvifs[vifi].uv_flags & VIFF_BLASTER) if (datalen > 0) { queue_blaster_report(vifi, src, dst, p, datalen, level); return; } else { datalen = -datalen; } if (!(nbr = update_neighbor(vifi, src, DVMRP_REPORT, NULL, 0, level))) return; if (datalen > 2*4096) { log(LOG_INFO, 0, "ignoring oversize (%d bytes) route report from %s", datalen, inet_fmt(src, s1)); return; } while (datalen > 0) { /* Loop through per-mask lists. */ if (datalen < 3) { log(LOG_WARNING, 0, "received truncated route report from %s", inet_fmt(src, s1)); return; } ((u_char *)&mask)[0] = 0xff; width = 1; if ((((u_char *)&mask)[1] = *p++) != 0) width = 2; if ((((u_char *)&mask)[2] = *p++) != 0) width = 3; if ((((u_char *)&mask)[3] = *p++) != 0) width = 4; if (!inet_valid_mask(ntohl(mask))) { log(LOG_WARNING, 0, "%s reports bogus netmask 0x%08x (%s)", inet_fmt(src, s1), ntohl(mask), inet_fmt(mask, s2)); return; } datalen -= 3; do { /* Loop through (origin, metric) pairs */ if (datalen < width + 1) { log(LOG_WARNING, 0, "received truncated route report from %s", inet_fmt(src, s1)); return; } origin = 0; for (i = 0; i < width; ++i) ((char *)&origin)[i] = *p++; metric = *p++; datalen -= width + 1; rt[nrt].mask = mask; rt[nrt].origin = origin; rt[nrt].metric = (metric & 0x7f); ++nrt; } while (!(metric & 0x80)); } qsort((char*)rt, nrt, sizeof(rt[0]), compare_rts); start_route_updates(); /* * If the last entry is default, change mask from 0xff000000 to 0 */ if (rt[nrt-1].origin == 0) rt[nrt-1].mask = 0; IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "Updating %d routes from %s to %s", nrt, inet_fmt(src, s1), inet_fmt(dst, s2)); for (i = 0; i < nrt; ++i) { if (i != 0 && rt[i].origin == rt[i-1].origin && rt[i].mask == rt[i-1].mask) { log(LOG_WARNING, 0, "%s reports duplicate route for %s", inet_fmt(src, s1), inet_fmts(rt[i].origin, rt[i].mask, s2)); continue; } /* Only filter non-poisoned updates. */ if (uvifs[vifi].uv_filter && rt[i].metric < UNREACHABLE) { struct vf_element *vfe; int match = 0; for (vfe = uvifs[vifi].uv_filter->vf_filter; vfe; vfe = vfe->vfe_next) { if (vfe->vfe_flags & VFEF_EXACT) { if ((vfe->vfe_addr == rt[i].origin) && (vfe->vfe_mask == rt[i].mask)) { match = 1; break; } } else { if ((rt[i].origin & vfe->vfe_mask) == vfe->vfe_addr) { match = 1; break; } } } if ((uvifs[vifi].uv_filter->vf_type == VFT_ACCEPT && match == 0) || (uvifs[vifi].uv_filter->vf_type == VFT_DENY && match == 1)) { IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "%s skipped on vif %d because it %s %s", inet_fmts(rt[i].origin, rt[i].mask, s1), vifi, match ? "matches" : "doesn't match", match ? inet_fmts(vfe->vfe_addr, vfe->vfe_mask, s2) : "the filter"); #if 0 rt[i].metric += vfe->vfe_addmetric; if (rt[i].metric > UNREACHABLE) #endif rt[i].metric = UNREACHABLE; } } update_route(rt[i].origin, rt[i].mask, rt[i].metric, src, vifi, nbr); } if (routes_changed && !delay_change_reports) report_to_all_neighbors(CHANGED_ROUTES); } /* * Send a route report message to destination 'dst', via virtual interface * 'vifi'. 'which_routes' specifies ALL_ROUTES or CHANGED_ROUTES. */ void report(int which_routes, vifi_t vifi, u_int32 dst) { struct rtentry *r; int i; r = rt_end; while (r != RT_ADDR) { i = report_chunk(which_routes, r, vifi, dst); while (i-- > 0) r = r->rt_prev; } } /* * Send a route report message to all neighboring routers. * 'which_routes' specifies ALL_ROUTES or CHANGED_ROUTES. */ void report_to_all_neighbors(int which_routes) { vifi_t vifi; struct uvif *v; struct rtentry *r; int routes_changed_before; /* * Remember the state of the global routes_changed flag before * generating the reports, and clear the flag. */ routes_changed_before = routes_changed; routes_changed = FALSE; for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (!NBRM_ISEMPTY(v->uv_nbrmap)) { report(which_routes, vifi, v->uv_dst_addr); } } /* * If there were changed routes before we sent the reports AND * if no new changes occurred while sending the reports, clear * the change flags in the individual route entries. If changes * did occur while sending the reports, new reports will be * generated at the next timer interrupt. */ if (routes_changed_before && !routes_changed) { for (r = routing_table; r != NULL; r = r->rt_next) { r->rt_flags &= ~RTF_CHANGED; } } /* * Set a flag to inhibit further reports of changed routes until the * next timer interrupt. This is to alleviate update storms. */ delay_change_reports = TRUE; } /* * Send a route report message to destination 'dst', via virtual interface * 'vifi'. 'which_routes' specifies ALL_ROUTES or CHANGED_ROUTES. */ static int report_chunk(int which_routes, struct rtentry *start_rt, vifi_t vifi, u_int32 dst) { struct rtentry *r; char *p; int i; int nrt = 0; struct uvif *v = &uvifs[vifi]; int datalen = 0; int width = 0; u_int32 mask = 0; u_int32 src; int admetric = v->uv_admetric; int metric; src = v->uv_lcl_addr; p = send_buf + MIN_IP_HEADER_LEN + IGMP_MINLEN; for (r = start_rt; r != RT_ADDR; r = r->rt_prev) { if (which_routes == CHANGED_ROUTES && !(r->rt_flags & RTF_CHANGED)) { nrt++; continue; } /* * Do not poison-reverse a route for a directly-connected * subnetwork on that subnetwork. This can cause loops when * some router on the subnetwork is misconfigured. */ if (r->rt_gateway == 0 && r->rt_parent == vifi) { nrt++; continue; } if (v->uv_filter && v->uv_filter->vf_flags & VFF_BIDIR) { struct vf_element *vfe; int match = 0; for (vfe = v->uv_filter->vf_filter; vfe; vfe = vfe->vfe_next) { if (vfe->vfe_flags & VFEF_EXACT) { if ((vfe->vfe_addr == r->rt_origin) && (vfe->vfe_mask == r->rt_originmask)) { match = 1; break; } } else { if ((r->rt_origin & vfe->vfe_mask) == vfe->vfe_addr) { match = 1; break; } } } if ((v->uv_filter->vf_type == VFT_ACCEPT && match == 0) || (v->uv_filter->vf_type == VFT_DENY && match == 1)) { IF_DEBUG(DEBUG_ROUTE) log(LOG_DEBUG, 0, "%s not reported on vif %d because it %s %s", RT_FMT(r, s1), vifi, match ? "matches" : "doesn't match", match ? inet_fmts(vfe->vfe_addr, vfe->vfe_mask, s2) : "the filter"); nrt++; continue; } } /* * If there is no room for this route in the current message, * send it & return how many routes we sent. */ if (datalen + ((r->rt_originmask == mask) ? (width + 1) : (r->rt_originwidth + 4)) > MAX_DVMRP_DATA_LEN) { *(p-1) |= 0x80; send_on_vif(v, 0, DVMRP_REPORT, datalen); return (nrt); } if (r->rt_originmask != mask || datalen == 0) { mask = r->rt_originmask; width = r->rt_originwidth; if (datalen != 0) *(p-1) |= 0x80; *p++ = ((char *)&mask)[1]; *p++ = ((char *)&mask)[2]; *p++ = ((char *)&mask)[3]; datalen += 3; } for (i = 0; i < width; ++i) *p++ = ((char *)&(r->rt_origin))[i]; metric = r->rt_metric + admetric; if (metric > UNREACHABLE) metric = UNREACHABLE; if (r->rt_parent != vifi && AVOID_TRANSIT(vifi, r)) metric = UNREACHABLE; *p++ = (r->rt_parent == vifi && metric != UNREACHABLE) ? (char)(metric + UNREACHABLE) : /* "poisoned reverse" */ (char)(metric); ++nrt; datalen += width + 1; } if (datalen != 0) { *(p-1) |= 0x80; send_on_vif(v, 0, DVMRP_REPORT, datalen); } return (nrt); } /* * send the next chunk of our routing table to all neighbors. * return the length of the smallest chunk we sent out. */ int report_next_chunk(void) { vifi_t vifi; struct uvif *v; struct rtentry *sr; int i, n = 0, min = 20000; static int start_rt; if (nroutes <= 0) return (0); /* * find this round's starting route. */ for (sr = rt_end, i = start_rt; --i >= 0; ) { sr = sr->rt_prev; if (sr == RT_ADDR) sr = rt_end; } /* * send one chunk of routes starting at this round's start to * all our neighbors. */ for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) { if (!NBRM_ISEMPTY(v->uv_nbrmap)) { n = report_chunk(ALL_ROUTES, sr, vifi, v->uv_dst_addr); if (n < min) min = n; } } if (min == 20000) min = 0; /* Neighborless router didn't send any routes */ n = min; IF_DEBUG(DEBUG_ROUTE) log(LOG_INFO, 0, "update %d starting at %d of %d", n, (nroutes - start_rt), nroutes); start_rt = (start_rt + n) % nroutes; return (n); } /* * Print the contents of the routing table on file 'fp'. */ void dump_routes(FILE *fp) { struct rtentry *r; vifi_t i; fprintf(fp, "Multicast Routing Table (%u %s)\n%s\n", nroutes, (nroutes == 1) ? "entry" : "entries", " Origin-Subnet From-Gateway Metric Tmr Fl In-Vif Out-Vifs"); for (r = routing_table; r != NULL; r = r->rt_next) { fprintf(fp, " %-18s %-15s ", inet_fmts(r->rt_origin, r->rt_originmask, s1), (r->rt_gateway == 0) ? "" : inet_fmt(r->rt_gateway, s2)); fprintf(fp, (r->rt_metric == UNREACHABLE) ? " NR " : "%4u ", r->rt_metric); fprintf(fp, " %3u %c%c %3u ", r->rt_timer, (r->rt_flags & RTF_CHANGED) ? 'C' : '.', (r->rt_flags & RTF_HOLDDOWN) ? 'H' : '.', r->rt_parent); for (i = 0; i < numvifs; ++i) { struct listaddr *n; char l = '['; if (VIFM_ISSET(i, r->rt_children)) { if ((uvifs[i].uv_flags & VIFF_TUNNEL) && !NBRM_ISSETMASK(uvifs[i].uv_nbrmap, r->rt_subordinates)) /* Don't print out parenthood of a leaf tunnel. */ continue; fprintf(fp, " %u", i); if (!NBRM_ISSETMASK(uvifs[i].uv_nbrmap, r->rt_subordinates)) fprintf(fp, "*"); for (n = uvifs[i].uv_neighbors; n; n = n->al_next) { if (NBRM_ISSET(n->al_index, r->rt_subordinates)) { fprintf(fp, "%c%d", l, n->al_index); l = ','; } } if (l == ',') fprintf(fp, "]"); } } fprintf(fp, "\n"); } fprintf(fp, "\n"); } struct rtentry * determine_route(u_int32 src) { struct rtentry *rt; for (rt = routing_table; rt != NULL; rt = rt->rt_next) { if (rt->rt_origin == (src & rt->rt_originmask) && rt->rt_metric != UNREACHABLE) break; } return rt; }