/* * Copyright (c) 1983, 1988, 1993 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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. * * @(#)output.c 8.1 (Berkeley) 6/5/93 * $FreeBSD: src/sbin/routed/output.c,v 1.5.2.1 2000/08/14 17:00:03 sheldonh Exp $ */ #include "defs.h" u_int update_seqno; /* walk the tree of routes with this for output */ struct { struct sockaddr_in to; naddr to_mask; naddr to_net; naddr to_std_mask; naddr to_std_net; struct interface *ifp; /* usually output interface */ struct auth *a; char metric; /* adjust metrics by interface */ int npackets; int gen_limit; u_int state; #define WS_ST_FLASH 0x001 /* send only changed routes */ #define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */ #define WS_ST_AG 0x004 /* ok to aggregate subnets */ #define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */ #define WS_ST_QUERY 0x010 /* responding to a query */ #define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */ #define WS_ST_DEFAULT 0x040 /* faking a default */ } ws; /* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */ struct ws_buf v12buf; union pkt_buf ripv12_buf; /* Another for only RIPv2 listeners */ struct ws_buf v2buf; union pkt_buf rip_v2_buf; void bufinit(void) { ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE; v12buf.buf = &ripv12_buf.rip; v12buf.base = &v12buf.buf->rip_nets[0]; rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE; rip_v2_buf.rip.rip_vers = RIPv2; v2buf.buf = &rip_v2_buf.rip; v2buf.base = &v2buf.buf->rip_nets[0]; } /* Send the contents of the global buffer via the non-multicast socket */ int /* <0 on failure */ output(enum output_type type, struct sockaddr_in *dst, /* send to here */ struct interface *ifp, struct rip *buf, int size) /* this many bytes */ { struct sockaddr_in in; int flags; const char *msg; int res; naddr tgt_mcast; int soc; int serrno; in = *dst; if (in.sin_port == 0) in.sin_port = htons(RIP_PORT); if (in.sin_len == 0) in.sin_len = sizeof(in); soc = rip_sock; flags = 0; switch (type) { case OUT_QUERY: msg = "Answer Query"; if (soc < 0) soc = ifp->int_rip_sock; break; case OUT_UNICAST: msg = "Send"; if (soc < 0) soc = ifp->int_rip_sock; flags = MSG_DONTROUTE; break; case OUT_BROADCAST: if (ifp->int_if_flags & IFF_POINTOPOINT) { msg = "Send"; } else { msg = "Send bcast"; } flags = MSG_DONTROUTE; break; case OUT_MULTICAST: if (ifp->int_if_flags & IFF_POINTOPOINT) { msg = "Send pt-to-pt"; } else if (ifp->int_state & IS_DUP) { trace_act("abort multicast output via %s" " with duplicate address", ifp->int_name); return 0; } else { msg = "Send mcast"; if (rip_sock_mcast != ifp) { #ifdef MCAST_PPP_BUG /* Do not specify the primary interface * explicitly if we have the multicast * point-to-point kernel bug, since the * kernel will do the wrong thing if the * local address of a point-to-point link * is the same as the address of an ordinary * interface. */ if (ifp->int_addr == myaddr) { tgt_mcast = 0; } else #endif tgt_mcast = ifp->int_addr; if (0 > setsockopt(rip_sock, IPPROTO_IP, IP_MULTICAST_IF, &tgt_mcast, sizeof(tgt_mcast))) { serrno = errno; LOGERR("setsockopt(rip_sock," "IP_MULTICAST_IF)"); errno = serrno; ifp = NULL; return -1; } rip_sock_mcast = ifp; } in.sin_addr.s_addr = htonl(INADDR_RIP_GROUP); } break; case NO_OUT_MULTICAST: case NO_OUT_RIPV2: default: #ifdef DEBUG abort(); #endif return -1; } trace_rip(msg, "to", &in, ifp, buf, size); res = sendto(soc, buf, size, flags, (struct sockaddr *)&in, sizeof(in)); if (res < 0 && (ifp == NULL || !(ifp->int_state & IS_BROKE))) { serrno = errno; msglog("%s sendto(%s%s%s.%d): %s", msg, ifp != NULL ? ifp->int_name : "", ifp != NULL ? ", " : "", inet_ntoa(in.sin_addr), ntohs(in.sin_port), strerror(errno)); errno = serrno; } return res; } /* Find the first key for a packet to send. * Try for a key that is eligible and has not expired, but settle for * the last key if they have all expired. * If no key is ready yet, give up. */ struct auth * find_auth(struct interface *ifp) { struct auth *ap, *res; int i; if (ifp == NULL) return 0; res = NULL; ap = ifp->int_auth; for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) { /* stop looking after the last key */ if (ap->type == RIP_AUTH_NONE) break; /* ignore keys that are not ready yet */ if ((u_long)ap->start > (u_long)clk.tv_sec) continue; if ((u_long)ap->end < (u_long)clk.tv_sec) { /* note best expired password as a fall-back */ if (res == NULL || (u_long)ap->end > (u_long)res->end) res = ap; continue; } /* note key with the best future */ if (res == NULL || (u_long)res->end < (u_long)ap->end) res = ap; } return res; } void clr_ws_buf(struct ws_buf *wb, struct auth *ap) { struct netauth *na; wb->lim = wb->base + NETS_LEN; wb->n = wb->base; memset(wb->n, 0, NETS_LEN*sizeof(*wb->n)); /* (start to) install authentication if appropriate */ if (ap == NULL) return; na = (struct netauth*)wb->n; if (ap->type == RIP_AUTH_PW) { na->a_family = RIP_AF_AUTH; na->a_type = RIP_AUTH_PW; memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw)); wb->n++; } else if (ap->type == RIP_AUTH_MD5) { na->a_family = RIP_AF_AUTH; na->a_type = RIP_AUTH_MD5; na->au.a_md5.md5_keyid = ap->keyid; na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_LEN; na->au.a_md5.md5_seqno = htonl(clk.tv_sec); wb->n++; wb->lim--; /* make room for trailer */ } } void end_md5_auth(struct ws_buf *wb, struct auth *ap) { struct netauth *na, *na2; MD5_CTX md5_ctx; int len; na = (struct netauth*)wb->base; na2 = (struct netauth*)wb->n; len = (char *)na2-(char *)wb->buf; na2->a_family = RIP_AF_AUTH; na2->a_type = htons(1); na->au.a_md5.md5_pkt_len = htons(len); MD5_Init(&md5_ctx); MD5_Update(&md5_ctx, (u_char *)wb->buf, len); MD5_Update(&md5_ctx, ap->key, RIP_AUTH_MD5_LEN); MD5_Final(na2->au.au_pw, &md5_ctx); wb->n++; } /* Send the buffer */ static void supply_write(struct ws_buf *wb) { /* Output multicast only if legal. * If we would multicast and it would be illegal, then discard the * packet. */ switch (wb->type) { case NO_OUT_MULTICAST: trace_pkt("skip multicast to %s because impossible", naddr_ntoa(ws.to.sin_addr.s_addr)); break; case NO_OUT_RIPV2: break; default: if (ws.a != NULL && ws.a->type == RIP_AUTH_MD5) end_md5_auth(wb,ws.a); if (output(wb->type, &ws.to, ws.ifp, wb->buf, ((char *)wb->n - (char*)wb->buf)) < 0 && ws.ifp != NULL) if_sick(ws.ifp); ws.npackets++; break; } clr_ws_buf(wb,ws.a); } /* put an entry into the packet */ static void supply_out(struct ag_info *ag) { int i; naddr mask, v1_mask, dst_h, ddst_h = 0; struct ws_buf *wb; /* Skip this route if doing a flash update and it and the routes * it aggregates have not changed recently. */ if (ag->ag_seqno < update_seqno && (ws.state & WS_ST_FLASH)) return; dst_h = ag->ag_dst_h; mask = ag->ag_mask; v1_mask = ripv1_mask_host(htonl(dst_h), (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0); i = 0; /* If we are sending RIPv2 packets that cannot (or must not) be * heard by RIPv1 listeners, do not worry about sub- or supernets. * Subnets (from other networks) can only be sent via multicast. * A pair of subnet routes might have been promoted so that they * are legal to send by RIPv1. * If RIPv1 is off, use the multicast buffer. */ if ((ws.state & WS_ST_RIP2_ALL) || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) { /* use the RIPv2-only buffer */ wb = &v2buf; } else { /* use the RIPv1-or-RIPv2 buffer */ wb = &v12buf; /* Convert supernet route into corresponding set of network * routes for RIPv1, but leave non-contiguous netmasks * to ag_check(). */ if (v1_mask > mask && mask + (mask & -mask) == 0) { ddst_h = v1_mask & -v1_mask; i = (v1_mask & ~mask)/ddst_h; if (i > ws.gen_limit) { /* Punt if we would have to generate an * unreasonable number of routes. */ if (TRACECONTENTS) trace_misc("sending %s-->%s as 1" " instead of %d routes", addrname(htonl(dst_h), mask, 1), naddr_ntoa(ws.to.sin_addr .s_addr), i+1); i = 0; } else { mask = v1_mask; ws.gen_limit -= i; } } } do { wb->n->n_family = RIP_AF_INET; wb->n->n_dst = htonl(dst_h); /* If the route is from router-discovery or we are * shutting down, admit only a bad metric. */ wb->n->n_metric = ((stopint || ag->ag_metric < 1) ? HOPCNT_INFINITY : ag->ag_metric); wb->n->n_metric = htonl(wb->n->n_metric); /* Any non-zero bits in the supposedly unused RIPv1 fields * cause the old `routed` to ignore the route. * That means the mask and so forth cannot be sent * in the hybrid RIPv1/RIPv2 mode. */ if (ws.state & WS_ST_RIP2_ALL) { if (ag->ag_nhop != 0 && ((ws.state & WS_ST_QUERY) || (ag->ag_nhop != ws.ifp->int_addr && on_net(ag->ag_nhop, ws.ifp->int_net, ws.ifp->int_mask)))) wb->n->n_nhop = ag->ag_nhop; wb->n->n_mask = htonl(mask); wb->n->n_tag = ag->ag_tag; } dst_h += ddst_h; if (++wb->n >= wb->lim) supply_write(wb); } while (i-- != 0); } /* supply one route from the table */ static int walk_supply(struct radix_node *rn, void *argp __unused) { #define RT ((struct rt_entry *)rn) u_short ags; char metric, pref; naddr dst, nhop; struct rt_spare *rts; int i; /* Do not advertise external remote interfaces or passive interfaces. */ if ((RT->rt_state & RS_IF) && RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_PASSIVE) && !(RT->rt_state & RS_MHOME)) return 0; /* If being quiet about our ability to forward, then * do not say anything unless responding to a query, * except about our main interface. */ if (!supplier && !(ws.state & WS_ST_QUERY) && !(RT->rt_state & RS_MHOME)) return 0; dst = RT->rt_dst; /* do not collide with the fake default route */ if (dst == RIP_DEFAULT && (ws.state & WS_ST_DEFAULT)) return 0; if (RT->rt_state & RS_NET_SYN) { if (RT->rt_state & RS_NET_INT) { /* Do not send manual synthetic network routes * into the subnet. */ if (on_net(ws.to.sin_addr.s_addr, ntohl(dst), RT->rt_mask)) return 0; } else { /* Do not send automatic synthetic network routes * if they are not needed because no RIPv1 listeners * can hear them. */ if (ws.state & WS_ST_RIP2_ALL) return 0; /* Do not send automatic synthetic network routes to * the real subnet. */ if (on_net(ws.to.sin_addr.s_addr, ntohl(dst), RT->rt_mask)) return 0; } nhop = 0; } else { /* Advertise the next hop if this is not a route for one * of our interfaces and the next hop is on the same * network as the target. * The final determination is made by supply_out(). */ if (!(RT->rt_state & RS_IF) && RT->rt_gate != myaddr && RT->rt_gate != loopaddr) nhop = RT->rt_gate; else nhop = 0; } metric = RT->rt_metric; ags = 0; if (RT->rt_state & RS_MHOME) { /* retain host route of multi-homed servers */ ; } else if (RT_ISHOST(RT)) { /* We should always suppress (into existing network routes) * the host routes for the local end of our point-to-point * links. * If we are suppressing host routes in general, then do so. * Avoid advertising host routes onto their own network, * where they should be handled by proxy-ARP. */ if ((RT->rt_state & RS_LOCAL) || ridhosts || on_net(dst, ws.to_net, ws.to_mask)) ags |= AGS_SUPPRESS; /* Aggregate stray host routes into network routes if allowed. * We cannot aggregate host routes into small network routes * without confusing RIPv1 listeners into thinking the * network routes are host routes. */ if ((ws.state & WS_ST_AG) && !(ws.state & WS_ST_RIP2_ALL)) ags |= AGS_AGGREGATE; } else { /* Always suppress network routes into other, existing * network routes */ ags |= AGS_SUPPRESS; /* Generate supernets if allowed. * If we can be heard by RIPv1 systems, we will * later convert back to ordinary nets. * This unifies dealing with received supernets. */ if ((ws.state & WS_ST_AG) && ((RT->rt_state & RS_SUBNET) || (ws.state & WS_ST_SUPER_AG))) ags |= AGS_AGGREGATE; } /* Do not send RIPv1 advertisements of subnets to other * networks. If possible, multicast them by RIPv2. */ if ((RT->rt_state & RS_SUBNET) && !(ws.state & WS_ST_RIP2_ALL) && !on_net(dst, ws.to_std_net, ws.to_std_mask)) ags |= AGS_RIPV2 | AGS_AGGREGATE; /* Do not send a route back to where it came from, except in * response to a query. This is "split-horizon". That means not * advertising back to the same network and so via the same interface. * * We want to suppress routes that might have been fragmented * from this route by a RIPv1 router and sent back to us, and so we * cannot forget this route here. Let the split-horizon route * suppress the fragmented routes and then itself be forgotten. * * Include the routes for both ends of point-to-point interfaces * among those suppressed by split-horizon, since the other side * should knows them as well as we do. * * Notice spare routes with the same metric that we are about to * advertise, to split the horizon on redundant, inactive paths. */ if (ws.ifp != NULL && !(ws.state & WS_ST_QUERY) && (ws.state & WS_ST_TO_ON_NET) && (!(RT->rt_state & RS_IF) || ws.ifp->int_if_flags & IFF_POINTOPOINT)) { for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) { if (rts->rts_metric > metric || rts->rts_ifp != ws.ifp) continue; /* If we do not mark the route with AGS_SPLIT_HZ here, * it will be poisoned-reverse, or advertised back * toward its source with an infinite metric. * If we have recently advertised the route with a * better metric than we now have, then we should * poison-reverse the route before suppressing it for * split-horizon. * * In almost all cases, if there is no spare for the * route then it is either old and dead or a brand * new route. If it is brand new, there is no need * for poison-reverse. If it is old and dead, it * is already poisoned. */ if (RT->rt_poison_time < now_expire || RT->rt_poison_metric >= metric || RT->rt_spares[1].rts_gate == 0) { ags |= AGS_SPLIT_HZ; ags &= ~AGS_SUPPRESS; } metric = HOPCNT_INFINITY; break; } } /* Keep track of the best metric with which the * route has been advertised recently. */ if (RT->rt_poison_metric >= metric || RT->rt_poison_time < now_expire) { RT->rt_poison_time = now.tv_sec; RT->rt_poison_metric = metric; } /* Adjust the outgoing metric by the cost of the link. * Avoid aggregation when a route is counting to infinity. */ pref = RT->rt_poison_metric + ws.metric; metric += ws.metric; /* Do not advertise stable routes that will be ignored, * unless we are answering a query. * If the route recently was advertised with a metric that * would have been less than infinity through this interface, * we need to continue to advertise it in order to poison it. */ if (metric >= HOPCNT_INFINITY) { if (!(ws.state & WS_ST_QUERY) && (pref >= HOPCNT_INFINITY || RT->rt_poison_time < now_garbage)) return 0; metric = HOPCNT_INFINITY; } ag_check(dst, RT->rt_mask, 0, nhop, metric, pref, RT->rt_seqno, RT->rt_tag, ags, supply_out); return 0; #undef RT } /* Supply dst with the contents of the routing tables. * If this won't fit in one packet, chop it up into several. */ void supply(struct sockaddr_in *dst, struct interface *ifp, /* output interface */ enum output_type type, int flash, /* 1=flash update */ int vers, /* RIP version */ int passwd_ok) /* OK to include cleartext password */ { struct rt_entry *rt; int def_metric; ws.state = 0; ws.gen_limit = 1024; ws.to = *dst; ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr); ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask; if (ifp != NULL) { ws.to_mask = ifp->int_mask; ws.to_net = ifp->int_net; if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask)) ws.state |= WS_ST_TO_ON_NET; } else { ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0); ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask; rt = rtfind(dst->sin_addr.s_addr); if (rt) ifp = rt->rt_ifp; } ws.npackets = 0; if (flash) ws.state |= WS_ST_FLASH; if ((ws.ifp = ifp) == NULL) { ws.metric = 1; } else { /* Adjust the advertised metric by the outgoing interface * metric. */ ws.metric = ifp->int_metric+1; } ripv12_buf.rip.rip_vers = vers; switch (type) { case OUT_MULTICAST: if (ifp->int_if_flags & IFF_MULTICAST) v2buf.type = OUT_MULTICAST; else v2buf.type = NO_OUT_MULTICAST; v12buf.type = OUT_BROADCAST; break; case OUT_QUERY: ws.state |= WS_ST_QUERY; /* fall through */ case OUT_BROADCAST: case OUT_UNICAST: v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2; v12buf.type = type; break; case NO_OUT_MULTICAST: case NO_OUT_RIPV2: break; /* no output */ } if (vers == RIPv2) { /* full RIPv2 only if cannot be heard by RIPv1 listeners */ if (type != OUT_BROADCAST) ws.state |= WS_ST_RIP2_ALL; if ((ws.state & WS_ST_QUERY) || !(ws.state & WS_ST_TO_ON_NET)) { ws.state |= (WS_ST_AG | WS_ST_SUPER_AG); } else if (ifp == NULL || !(ifp->int_state & IS_NO_AG)) { ws.state |= WS_ST_AG; if (type != OUT_BROADCAST && (ifp == NULL || !(ifp->int_state & IS_NO_SUPER_AG))) ws.state |= WS_ST_SUPER_AG; } } ws.a = (vers == RIPv2) ? find_auth(ifp) : 0; if (!passwd_ok && ws.a != NULL && ws.a->type == RIP_AUTH_PW) ws.a = NULL; clr_ws_buf(&v12buf,ws.a); clr_ws_buf(&v2buf,ws.a); /* Fake a default route if asked and if there is not already * a better, real default route. */ if (supplier && (def_metric = ifp->int_d_metric) != 0) { if (NULL == (rt = rtget(RIP_DEFAULT, 0)) || rt->rt_metric+ws.metric >= def_metric) { ws.state |= WS_ST_DEFAULT; ag_check(0, 0, 0, 0, def_metric, def_metric, 0, 0, 0, supply_out); } else { def_metric = rt->rt_metric+ws.metric; } /* If both RIPv2 and the poor-man's router discovery * kludge are on, arrange to advertise an extra * default route via RIPv1. */ if ((ws.state & WS_ST_RIP2_ALL) && (ifp->int_state & IS_PM_RDISC)) { ripv12_buf.rip.rip_vers = RIPv1; v12buf.n->n_family = RIP_AF_INET; v12buf.n->n_dst = htonl(RIP_DEFAULT); v12buf.n->n_metric = htonl(def_metric); v12buf.n++; } } rhead->rnh_walktree(rhead, walk_supply, NULL); ag_flush(0, 0, supply_out); /* Flush the packet buffers, provided they are not empty and * do not contain only the password. */ if (v12buf.n != v12buf.base && (v12buf.n > v12buf.base+1 || v12buf.base->n_family != RIP_AF_AUTH)) supply_write(&v12buf); if (v2buf.n != v2buf.base && (v2buf.n > v2buf.base+1 || v2buf.base->n_family != RIP_AF_AUTH)) supply_write(&v2buf); /* If we sent nothing and this is an answer to a query, send * an empty buffer. */ if (ws.npackets == 0 && (ws.state & WS_ST_QUERY)) supply_write(&v12buf); } /* send all of the routing table or just do a flash update */ void rip_bcast(int flash) { static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}}; struct interface *ifp; enum output_type type; int vers; struct timeval rtime; need_flash = 0; intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME); no_flash = rtime; timevaladd(&no_flash, &now); if (rip_sock < 0) return; trace_act("send %s and inhibit dynamic updates for %.3f sec", flash ? "dynamic update" : "all routes", rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0); for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) { /* Skip interfaces not doing RIP. * Do try broken interfaces to see if they have healed. */ if (IS_RIP_OUT_OFF(ifp->int_state)) continue; /* skip turned off interfaces */ if (!iff_up(ifp->int_if_flags)) continue; vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1; if (ifp->int_if_flags & IFF_BROADCAST) { /* ordinary, hardware interface */ dst.sin_addr.s_addr = ifp->int_brdaddr; if (vers == RIPv2 && !(ifp->int_state & IS_NO_RIP_MCAST)) { type = OUT_MULTICAST; } else { type = OUT_BROADCAST; } } else if (ifp->int_if_flags & IFF_POINTOPOINT) { /* point-to-point hardware interface */ dst.sin_addr.s_addr = ifp->int_dstaddr; type = OUT_UNICAST; } else if (ifp->int_state & IS_REMOTE) { /* remote interface */ dst.sin_addr.s_addr = ifp->int_addr; type = OUT_UNICAST; } else { /* ATM, HIPPI, etc. */ continue; } supply(&dst, ifp, type, flash, vers, 1); } update_seqno++; /* all routes are up to date */ } /* Ask for routes * Do it only once to an interface, and not even after the interface * was broken and recovered. */ void rip_query(void) { static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}}; struct interface *ifp; struct rip buf; enum output_type type; if (rip_sock < 0) return; memset(&buf, 0, sizeof(buf)); for (ifp = ifnet; ifp; ifp = ifp->int_next) { /* Skip interfaces those already queried. * Do not ask via interfaces through which we don't * accept input. Do not ask via interfaces that cannot * send RIP packets. * Do try broken interfaces to see if they have healed. */ if (IS_RIP_IN_OFF(ifp->int_state) || ifp->int_query_time != NEVER) continue; /* skip turned off interfaces */ if (!iff_up(ifp->int_if_flags)) continue; buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1; buf.rip_cmd = RIPCMD_REQUEST; buf.rip_nets[0].n_family = RIP_AF_UNSPEC; buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY); /* Send a RIPv1 query only if allowed and if we will * listen to RIPv1 routers. */ if ((ifp->int_state & IS_NO_RIPV1_OUT) || (ifp->int_state & IS_NO_RIPV1_IN)) { buf.rip_vers = RIPv2; } else { buf.rip_vers = RIPv1; } if (ifp->int_if_flags & IFF_BROADCAST) { /* ordinary, hardware interface */ dst.sin_addr.s_addr = ifp->int_brdaddr; /* Broadcast RIPv1 queries and RIPv2 queries * when the hardware cannot multicast. */ if (buf.rip_vers == RIPv2 && (ifp->int_if_flags & IFF_MULTICAST) && !(ifp->int_state & IS_NO_RIP_MCAST)) { type = OUT_MULTICAST; } else { type = OUT_BROADCAST; } } else if (ifp->int_if_flags & IFF_POINTOPOINT) { /* point-to-point hardware interface */ dst.sin_addr.s_addr = ifp->int_dstaddr; type = OUT_UNICAST; } else if (ifp->int_state & IS_REMOTE) { /* remote interface */ dst.sin_addr.s_addr = ifp->int_addr; type = OUT_UNICAST; } else { /* ATM, HIPPI, etc. */ continue; } ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL; if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0) if_sick(ifp); } }