1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1983, 1988, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * $FreeBSD$
32 */
33
34 #include "defs.h"
35
36 __RCSID("$FreeBSD$");
37
38
39 u_int update_seqno;
40
41
42 /* walk the tree of routes with this for output
43 */
44 static struct {
45 struct sockaddr_in to;
46 naddr to_mask;
47 naddr to_net;
48 naddr to_std_mask;
49 naddr to_std_net;
50 struct interface *ifp; /* usually output interface */
51 struct auth *a;
52 char metric; /* adjust metrics by interface */
53 int npackets;
54 int gen_limit;
55 u_int state;
56 #define WS_ST_FLASH 0x001 /* send only changed routes */
57 #define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */
58 #define WS_ST_AG 0x004 /* ok to aggregate subnets */
59 #define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */
60 #define WS_ST_QUERY 0x010 /* responding to a query */
61 #define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */
62 #define WS_ST_DEFAULT 0x040 /* faking a default */
63 } ws;
64
65 /* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */
66 struct ws_buf v12buf;
67 static union pkt_buf ripv12_buf;
68
69 /* Another for only RIPv2 listeners */
70 static struct ws_buf v2buf;
71 static union pkt_buf rip_v2_buf;
72
73
74
75 void
bufinit(void)76 bufinit(void)
77 {
78 ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE;
79 v12buf.buf = &ripv12_buf.rip;
80 v12buf.base = &v12buf.buf->rip_nets[0];
81
82 rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE;
83 rip_v2_buf.rip.rip_vers = RIPv2;
84 v2buf.buf = &rip_v2_buf.rip;
85 v2buf.base = &v2buf.buf->rip_nets[0];
86 }
87
88
89 /* Send the contents of the global buffer via the non-multicast socket
90 */
91 int /* <0 on failure */
output(enum output_type type,struct sockaddr_in * dst,struct interface * ifp,struct rip * buf,int size)92 output(enum output_type type,
93 struct sockaddr_in *dst, /* send to here */
94 struct interface *ifp,
95 struct rip *buf,
96 int size) /* this many bytes */
97 {
98 struct sockaddr_in osin;
99 int flags;
100 const char *msg;
101 int res;
102 int soc;
103 int serrno;
104
105 assert(ifp != NULL);
106 osin = *dst;
107 if (osin.sin_port == 0)
108 osin.sin_port = htons(RIP_PORT);
109 #ifdef _HAVE_SIN_LEN
110 if (osin.sin_len == 0)
111 osin.sin_len = sizeof(osin);
112 #endif
113
114 soc = rip_sock;
115 flags = 0;
116
117 switch (type) {
118 case OUT_QUERY:
119 msg = "Answer Query";
120 if (soc < 0)
121 soc = ifp->int_rip_sock;
122 break;
123 case OUT_UNICAST:
124 msg = "Send";
125 if (soc < 0)
126 soc = ifp->int_rip_sock;
127 flags = MSG_DONTROUTE;
128 break;
129 case OUT_BROADCAST:
130 if (ifp->int_if_flags & IFF_POINTOPOINT) {
131 msg = "Send";
132 } else {
133 msg = "Send bcast";
134 }
135 flags = MSG_DONTROUTE;
136 break;
137 case OUT_MULTICAST:
138 if ((ifp->int_if_flags & (IFF_POINTOPOINT|IFF_MULTICAST)) ==
139 IFF_POINTOPOINT) {
140 msg = "Send pt-to-pt";
141 } else if (ifp->int_state & IS_DUP) {
142 trace_act("abort multicast output via %s"
143 " with duplicate address",
144 ifp->int_name);
145 return 0;
146 } else {
147 msg = "Send mcast";
148 if (rip_sock_mcast != ifp) {
149 struct ip_mreqn mreqn;
150
151 memset(&mreqn, 0, sizeof(struct ip_mreqn));
152 mreqn.imr_ifindex = ifp->int_index;
153 if (0 > setsockopt(rip_sock,
154 IPPROTO_IP,
155 IP_MULTICAST_IF,
156 &mreqn,
157 sizeof(mreqn))) {
158 serrno = errno;
159 LOGERR("setsockopt(rip_sock, "
160 "IP_MULTICAST_IF)");
161 errno = serrno;
162 ifp = NULL;
163 return -1;
164 }
165 rip_sock_mcast = ifp;
166 }
167 osin.sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
168 }
169 break;
170
171 case NO_OUT_MULTICAST:
172 case NO_OUT_RIPV2:
173 default:
174 #ifdef DEBUG
175 abort();
176 #endif
177 return -1;
178 }
179
180 trace_rip(msg, "to", &osin, ifp, buf, size);
181
182 res = sendto(soc, buf, size, flags,
183 (struct sockaddr *)&osin, sizeof(osin));
184 if (res < 0
185 && (ifp == NULL || !(ifp->int_state & IS_BROKE))) {
186 serrno = errno;
187 msglog("%s sendto(%s%s%s.%d): %s", msg,
188 ifp != NULL ? ifp->int_name : "",
189 ifp != NULL ? ", " : "",
190 inet_ntoa(osin.sin_addr),
191 ntohs(osin.sin_port),
192 strerror(errno));
193 errno = serrno;
194 }
195
196 return res;
197 }
198
199
200 /* Find the first key for a packet to send.
201 * Try for a key that is eligible and has not expired, but settle for
202 * the last key if they have all expired.
203 * If no key is ready yet, give up.
204 */
205 struct auth *
find_auth(struct interface * ifp)206 find_auth(struct interface *ifp)
207 {
208 struct auth *ap, *res;
209 int i;
210
211
212 if (ifp == NULL)
213 return 0;
214
215 res = NULL;
216 ap = ifp->int_auth;
217 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) {
218 /* stop looking after the last key */
219 if (ap->type == RIP_AUTH_NONE)
220 break;
221
222 /* ignore keys that are not ready yet */
223 if ((u_long)ap->start > (u_long)clk.tv_sec)
224 continue;
225
226 if ((u_long)ap->end < (u_long)clk.tv_sec) {
227 /* note best expired password as a fall-back */
228 if (res == NULL || (u_long)ap->end > (u_long)res->end)
229 res = ap;
230 continue;
231 }
232
233 /* note key with the best future */
234 if (res == NULL || (u_long)res->end < (u_long)ap->end)
235 res = ap;
236 }
237 return res;
238 }
239
240
241 void
clr_ws_buf(struct ws_buf * wb,struct auth * ap)242 clr_ws_buf(struct ws_buf *wb,
243 struct auth *ap)
244 {
245 struct netauth *na;
246
247 wb->lim = wb->base + NETS_LEN;
248 wb->n = wb->base;
249 memset(wb->n, 0, NETS_LEN*sizeof(*wb->n));
250
251 /* (start to) install authentication if appropriate
252 */
253 if (ap == NULL)
254 return;
255
256 na = (struct netauth*)wb->n;
257 if (ap->type == RIP_AUTH_PW) {
258 na->a_family = RIP_AF_AUTH;
259 na->a_type = RIP_AUTH_PW;
260 memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw));
261 wb->n++;
262
263 } else if (ap->type == RIP_AUTH_MD5) {
264 na->a_family = RIP_AF_AUTH;
265 na->a_type = RIP_AUTH_MD5;
266 na->au.a_md5.md5_keyid = ap->keyid;
267 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_KEY_LEN;
268 na->au.a_md5.md5_seqno = htonl(clk.tv_sec);
269 wb->n++;
270 wb->lim--; /* make room for trailer */
271 }
272 }
273
274
275 void
end_md5_auth(struct ws_buf * wb,struct auth * ap)276 end_md5_auth(struct ws_buf *wb,
277 struct auth *ap)
278 {
279 struct netauth *na, *na2;
280 MD5_CTX md5_ctx;
281 int len;
282
283
284 na = (struct netauth*)wb->base;
285 na2 = (struct netauth*)wb->n;
286 len = (char *)na2-(char *)wb->buf;
287 na2->a_family = RIP_AF_AUTH;
288 na2->a_type = htons(1);
289 na->au.a_md5.md5_pkt_len = htons(len);
290 MD5Init(&md5_ctx);
291 MD5Update(&md5_ctx, (u_char *)wb->buf, len + RIP_AUTH_MD5_HASH_XTRA);
292 MD5Update(&md5_ctx, ap->key, RIP_AUTH_MD5_KEY_LEN);
293 MD5Final(na2->au.au_pw, &md5_ctx);
294 wb->n++;
295 }
296
297
298 /* Send the buffer
299 */
300 static void
supply_write(struct ws_buf * wb)301 supply_write(struct ws_buf *wb)
302 {
303 /* Output multicast only if legal.
304 * If we would multicast and it would be illegal, then discard the
305 * packet.
306 */
307 switch (wb->type) {
308 case NO_OUT_MULTICAST:
309 trace_pkt("skip multicast to %s because impossible",
310 naddr_ntoa(ws.to.sin_addr.s_addr));
311 break;
312 case NO_OUT_RIPV2:
313 break;
314 default:
315 if (ws.a != NULL && ws.a->type == RIP_AUTH_MD5)
316 end_md5_auth(wb,ws.a);
317 if (output(wb->type, &ws.to, ws.ifp, wb->buf,
318 ((char *)wb->n - (char*)wb->buf)) < 0
319 && ws.ifp != NULL)
320 if_sick(ws.ifp);
321 ws.npackets++;
322 break;
323 }
324
325 clr_ws_buf(wb,ws.a);
326 }
327
328
329 /* put an entry into the packet
330 */
331 static void
supply_out(struct ag_info * ag)332 supply_out(struct ag_info *ag)
333 {
334 int i;
335 naddr mask, v1_mask, dst_h, ddst_h = 0;
336 struct ws_buf *wb;
337
338
339 /* Skip this route if doing a flash update and it and the routes
340 * it aggregates have not changed recently.
341 */
342 if (ag->ag_seqno < update_seqno
343 && (ws.state & WS_ST_FLASH))
344 return;
345
346 dst_h = ag->ag_dst_h;
347 mask = ag->ag_mask;
348 v1_mask = ripv1_mask_host(htonl(dst_h),
349 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0);
350 i = 0;
351
352 /* If we are sending RIPv2 packets that cannot (or must not) be
353 * heard by RIPv1 listeners, do not worry about sub- or supernets.
354 * Subnets (from other networks) can only be sent via multicast.
355 * A pair of subnet routes might have been promoted so that they
356 * are legal to send by RIPv1.
357 * If RIPv1 is off, use the multicast buffer.
358 */
359 if ((ws.state & WS_ST_RIP2_ALL)
360 || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) {
361 /* use the RIPv2-only buffer */
362 wb = &v2buf;
363
364 } else {
365 /* use the RIPv1-or-RIPv2 buffer */
366 wb = &v12buf;
367
368 /* Convert supernet route into corresponding set of network
369 * routes for RIPv1, but leave non-contiguous netmasks
370 * to ag_check().
371 */
372 if (v1_mask > mask
373 && mask + (mask & -mask) == 0) {
374 ddst_h = v1_mask & -v1_mask;
375 i = (v1_mask & ~mask)/ddst_h;
376
377 if (i > ws.gen_limit) {
378 /* Punt if we would have to generate an
379 * unreasonable number of routes.
380 */
381 if (TRACECONTENTS)
382 trace_misc("sending %s-->%s as 1"
383 " instead of %d routes",
384 addrname(htonl(dst_h), mask,
385 1),
386 naddr_ntoa(ws.to.sin_addr
387 .s_addr),
388 i+1);
389 i = 0;
390
391 } else {
392 mask = v1_mask;
393 ws.gen_limit -= i;
394 }
395 }
396 }
397
398 do {
399 wb->n->n_family = RIP_AF_INET;
400 wb->n->n_dst = htonl(dst_h);
401 /* If the route is from router-discovery or we are
402 * shutting down, admit only a bad metric.
403 */
404 wb->n->n_metric = ((stopint || ag->ag_metric < 1)
405 ? HOPCNT_INFINITY
406 : ag->ag_metric);
407 wb->n->n_metric = htonl(wb->n->n_metric);
408 /* Any non-zero bits in the supposedly unused RIPv1 fields
409 * cause the old `routed` to ignore the route.
410 * That means the mask and so forth cannot be sent
411 * in the hybrid RIPv1/RIPv2 mode.
412 */
413 if (ws.state & WS_ST_RIP2_ALL) {
414 if (ag->ag_nhop != 0
415 && ((ws.state & WS_ST_QUERY)
416 || (ag->ag_nhop != ws.ifp->int_addr
417 && on_net(ag->ag_nhop,
418 ws.ifp->int_net,
419 ws.ifp->int_mask))))
420 wb->n->n_nhop = ag->ag_nhop;
421 wb->n->n_mask = htonl(mask);
422 wb->n->n_tag = ag->ag_tag;
423 }
424 dst_h += ddst_h;
425
426 if (++wb->n >= wb->lim)
427 supply_write(wb);
428 } while (i-- != 0);
429 }
430
431
432 /* supply one route from the table
433 */
434 /* ARGSUSED */
435 static int
walk_supply(struct radix_node * rn,struct walkarg * argp UNUSED)436 walk_supply(struct radix_node *rn,
437 struct walkarg *argp UNUSED)
438 {
439 #define RT ((struct rt_entry *)rn)
440 u_short ags;
441 char metric, pref;
442 naddr dst, nhop;
443 struct rt_spare *rts;
444 int i;
445
446
447 /* Do not advertise external remote interfaces or passive interfaces.
448 */
449 if ((RT->rt_state & RS_IF)
450 && RT->rt_ifp != 0
451 && (RT->rt_ifp->int_state & IS_PASSIVE)
452 && !(RT->rt_state & RS_MHOME))
453 return 0;
454
455 /* If being quiet about our ability to forward, then
456 * do not say anything unless responding to a query,
457 * except about our main interface.
458 */
459 if (!supplier && !(ws.state & WS_ST_QUERY)
460 && !(RT->rt_state & RS_MHOME))
461 return 0;
462
463 dst = RT->rt_dst;
464
465 /* do not collide with the fake default route */
466 if (dst == RIP_DEFAULT
467 && (ws.state & WS_ST_DEFAULT))
468 return 0;
469
470 if (RT->rt_state & RS_NET_SYN) {
471 if (RT->rt_state & RS_NET_INT) {
472 /* Do not send manual synthetic network routes
473 * into the subnet.
474 */
475 if (on_net(ws.to.sin_addr.s_addr,
476 ntohl(dst), RT->rt_mask))
477 return 0;
478
479 } else {
480 /* Do not send automatic synthetic network routes
481 * if they are not needed because no RIPv1 listeners
482 * can hear them.
483 */
484 if (ws.state & WS_ST_RIP2_ALL)
485 return 0;
486
487 /* Do not send automatic synthetic network routes to
488 * the real subnet.
489 */
490 if (on_net(ws.to.sin_addr.s_addr,
491 ntohl(dst), RT->rt_mask))
492 return 0;
493 }
494 nhop = 0;
495
496 } else {
497 /* Advertise the next hop if this is not a route for one
498 * of our interfaces and the next hop is on the same
499 * network as the target.
500 * The final determination is made by supply_out().
501 */
502 if (!(RT->rt_state & RS_IF)
503 && RT->rt_gate != myaddr
504 && RT->rt_gate != loopaddr)
505 nhop = RT->rt_gate;
506 else
507 nhop = 0;
508 }
509
510 metric = RT->rt_metric;
511 ags = 0;
512
513 if (RT->rt_state & RS_MHOME) {
514 /* retain host route of multi-homed servers */
515 ;
516
517 } else if (RT_ISHOST(RT)) {
518 /* We should always suppress (into existing network routes)
519 * the host routes for the local end of our point-to-point
520 * links.
521 * If we are suppressing host routes in general, then do so.
522 * Avoid advertising host routes onto their own network,
523 * where they should be handled by proxy-ARP.
524 */
525 if ((RT->rt_state & RS_LOCAL)
526 || ridhosts
527 || on_net(dst, ws.to_net, ws.to_mask))
528 ags |= AGS_SUPPRESS;
529
530 /* Aggregate stray host routes into network routes if allowed.
531 * We cannot aggregate host routes into small network routes
532 * without confusing RIPv1 listeners into thinking the
533 * network routes are host routes.
534 */
535 if ((ws.state & WS_ST_AG) && (ws.state & WS_ST_RIP2_ALL))
536 ags |= AGS_AGGREGATE;
537
538 } else {
539 /* Always suppress network routes into other, existing
540 * network routes
541 */
542 ags |= AGS_SUPPRESS;
543
544 /* Generate supernets if allowed.
545 * If we can be heard by RIPv1 systems, we will
546 * later convert back to ordinary nets.
547 * This unifies dealing with received supernets.
548 */
549 if ((ws.state & WS_ST_AG)
550 && ((RT->rt_state & RS_SUBNET)
551 || (ws.state & WS_ST_SUPER_AG)))
552 ags |= AGS_AGGREGATE;
553 }
554
555 /* Do not send RIPv1 advertisements of subnets to other
556 * networks. If possible, multicast them by RIPv2.
557 */
558 if ((RT->rt_state & RS_SUBNET)
559 && !(ws.state & WS_ST_RIP2_ALL)
560 && !on_net(dst, ws.to_std_net, ws.to_std_mask))
561 ags |= AGS_RIPV2 | AGS_AGGREGATE;
562
563
564 /* Do not send a route back to where it came from, except in
565 * response to a query. This is "split-horizon". That means not
566 * advertising back to the same network and so via the same interface.
567 *
568 * We want to suppress routes that might have been fragmented
569 * from this route by a RIPv1 router and sent back to us, and so we
570 * cannot forget this route here. Let the split-horizon route
571 * suppress the fragmented routes and then itself be forgotten.
572 *
573 * Include the routes for both ends of point-to-point interfaces
574 * among those suppressed by split-horizon, since the other side
575 * should knows them as well as we do.
576 *
577 * Notice spare routes with the same metric that we are about to
578 * advertise, to split the horizon on redundant, inactive paths.
579 *
580 * Do not suppress advertisements of interface-related addresses on
581 * non-point-to-point interfaces. This ensures that we have something
582 * to say every 30 seconds to help detect broken Ethernets or
583 * other interfaces where one packet every 30 seconds costs nothing.
584 */
585 if (ws.ifp != NULL
586 && !(ws.state & WS_ST_QUERY)
587 && (ws.state & WS_ST_TO_ON_NET)
588 && (!(RT->rt_state & RS_IF)
589 || ws.ifp->int_if_flags & IFF_POINTOPOINT)) {
590 for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) {
591 if (rts->rts_metric > metric
592 || rts->rts_ifp != ws.ifp)
593 continue;
594
595 /* If we do not mark the route with AGS_SPLIT_HZ here,
596 * it will be poisoned-reverse, or advertised back
597 * toward its source with an infinite metric.
598 * If we have recently advertised the route with a
599 * better metric than we now have, then we should
600 * poison-reverse the route before suppressing it for
601 * split-horizon.
602 *
603 * In almost all cases, if there is no spare for the
604 * route then it is either old and dead or a brand
605 * new route. If it is brand new, there is no need
606 * for poison-reverse. If it is old and dead, it
607 * is already poisoned.
608 */
609 if (RT->rt_poison_time < now_expire
610 || RT->rt_poison_metric >= metric
611 || RT->rt_spares[1].rts_gate == 0) {
612 ags |= AGS_SPLIT_HZ;
613 ags &= ~AGS_SUPPRESS;
614 }
615 metric = HOPCNT_INFINITY;
616 break;
617 }
618 }
619
620 /* Keep track of the best metric with which the
621 * route has been advertised recently.
622 */
623 if (RT->rt_poison_metric >= metric
624 || RT->rt_poison_time < now_expire) {
625 RT->rt_poison_time = now.tv_sec;
626 RT->rt_poison_metric = metric;
627 }
628
629 /* Adjust the outgoing metric by the cost of the link.
630 * Avoid aggregation when a route is counting to infinity.
631 */
632 pref = RT->rt_poison_metric + ws.metric;
633 metric += ws.metric;
634
635 /* Do not advertise stable routes that will be ignored,
636 * unless we are answering a query.
637 * If the route recently was advertised with a metric that
638 * would have been less than infinity through this interface,
639 * we need to continue to advertise it in order to poison it.
640 */
641 if (metric >= HOPCNT_INFINITY) {
642 if (!(ws.state & WS_ST_QUERY)
643 && (pref >= HOPCNT_INFINITY
644 || RT->rt_poison_time < now_garbage))
645 return 0;
646
647 metric = HOPCNT_INFINITY;
648 }
649
650 ag_check(dst, RT->rt_mask, 0, nhop, metric, pref,
651 RT->rt_seqno, RT->rt_tag, ags, supply_out);
652 return 0;
653 #undef RT
654 }
655
656
657 /* Supply dst with the contents of the routing tables.
658 * If this won't fit in one packet, chop it up into several.
659 */
660 void
supply(struct sockaddr_in * dst,struct interface * ifp,enum output_type type,int flash,int vers,int passwd_ok)661 supply(struct sockaddr_in *dst,
662 struct interface *ifp, /* output interface */
663 enum output_type type,
664 int flash, /* 1=flash update */
665 int vers, /* RIP version */
666 int passwd_ok) /* OK to include cleartext password */
667 {
668 struct rt_entry *rt;
669 int def_metric;
670
671 ws.state = 0;
672 ws.gen_limit = 1024;
673
674 ws.to = *dst;
675 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr);
676 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask;
677
678 if (ifp != NULL) {
679 ws.to_mask = ifp->int_mask;
680 ws.to_net = ifp->int_net;
681 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask))
682 ws.state |= WS_ST_TO_ON_NET;
683
684 } else {
685 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0);
686 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask;
687 rt = rtfind(dst->sin_addr.s_addr);
688 if (rt)
689 ifp = rt->rt_ifp;
690 }
691
692 ws.npackets = 0;
693 if (flash)
694 ws.state |= WS_ST_FLASH;
695
696 if ((ws.ifp = ifp) == NULL) {
697 ws.metric = 1;
698 } else {
699 /* Adjust the advertised metric by the outgoing interface
700 * metric.
701 */
702 ws.metric = ifp->int_metric + 1 + ifp->int_adj_outmetric;
703 }
704
705 ripv12_buf.rip.rip_vers = vers;
706
707 switch (type) {
708 case OUT_MULTICAST:
709 if (ifp != NULL && ifp->int_if_flags & IFF_MULTICAST)
710 v2buf.type = OUT_MULTICAST;
711 else
712 v2buf.type = NO_OUT_MULTICAST;
713 v12buf.type = OUT_BROADCAST;
714 break;
715
716 case OUT_QUERY:
717 ws.state |= WS_ST_QUERY;
718 /* FALLTHROUGH */
719 case OUT_BROADCAST:
720 case OUT_UNICAST:
721 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2;
722 v12buf.type = type;
723 break;
724
725 case NO_OUT_MULTICAST:
726 case NO_OUT_RIPV2:
727 break; /* no output */
728 }
729
730 if (vers == RIPv2) {
731 /* full RIPv2 only if cannot be heard by RIPv1 listeners */
732 if (type != OUT_BROADCAST)
733 ws.state |= WS_ST_RIP2_ALL;
734 if ((ws.state & WS_ST_QUERY)
735 || !(ws.state & WS_ST_TO_ON_NET)) {
736 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG);
737 } else if (ifp == NULL || !(ifp->int_state & IS_NO_AG)) {
738 ws.state |= WS_ST_AG;
739 if (type != OUT_BROADCAST
740 && (ifp == NULL
741 || !(ifp->int_state & IS_NO_SUPER_AG)))
742 ws.state |= WS_ST_SUPER_AG;
743 }
744 }
745
746 ws.a = (vers == RIPv2) ? find_auth(ifp) : 0;
747 if (!passwd_ok && ws.a != NULL && ws.a->type == RIP_AUTH_PW)
748 ws.a = NULL;
749 clr_ws_buf(&v12buf,ws.a);
750 clr_ws_buf(&v2buf,ws.a);
751
752 /* Fake a default route if asked and if there is not already
753 * a better, real default route.
754 */
755 if (supplier && ifp && (def_metric = ifp->int_d_metric) != 0) {
756 if ((rt = rtget(RIP_DEFAULT, 0)) == NULL
757 || rt->rt_metric+ws.metric >= def_metric) {
758 ws.state |= WS_ST_DEFAULT;
759 ag_check(0, 0, 0, 0, def_metric, def_metric,
760 0, 0, 0, supply_out);
761 } else {
762 def_metric = rt->rt_metric+ws.metric;
763 }
764
765 /* If both RIPv2 and the poor-man's router discovery
766 * kludge are on, arrange to advertise an extra
767 * default route via RIPv1.
768 */
769 if ((ws.state & WS_ST_RIP2_ALL)
770 && (ifp->int_state & IS_PM_RDISC)) {
771 ripv12_buf.rip.rip_vers = RIPv1;
772 v12buf.n->n_family = RIP_AF_INET;
773 v12buf.n->n_dst = htonl(RIP_DEFAULT);
774 v12buf.n->n_metric = htonl(def_metric);
775 v12buf.n++;
776 }
777 }
778
779 (void)rn_walktree(rhead, walk_supply, 0);
780 ag_flush(0,0,supply_out);
781
782 /* Flush the packet buffers, provided they are not empty and
783 * do not contain only the password.
784 */
785 if (v12buf.n != v12buf.base
786 && (v12buf.n > v12buf.base+1
787 || v12buf.base->n_family != RIP_AF_AUTH))
788 supply_write(&v12buf);
789 if (v2buf.n != v2buf.base
790 && (v2buf.n > v2buf.base+1
791 || v2buf.base->n_family != RIP_AF_AUTH))
792 supply_write(&v2buf);
793
794 /* If we sent nothing and this is an answer to a query, send
795 * an empty buffer.
796 */
797 if (ws.npackets == 0
798 && (ws.state & WS_ST_QUERY))
799 supply_write(&v12buf);
800 }
801
802
803 /* send all of the routing table or just do a flash update
804 */
805 void
rip_bcast(int flash)806 rip_bcast(int flash)
807 {
808 #ifdef _HAVE_SIN_LEN
809 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
810 #else
811 static struct sockaddr_in dst = {AF_INET};
812 #endif
813 struct interface *ifp;
814 enum output_type type;
815 int vers;
816 struct timeval rtime;
817
818
819 need_flash = 0;
820 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME);
821 no_flash = rtime;
822 timevaladd(&no_flash, &now);
823
824 if (rip_sock < 0)
825 return;
826
827 trace_act("send %s and inhibit dynamic updates for %.3f sec",
828 flash ? "dynamic update" : "all routes",
829 rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0);
830
831 LIST_FOREACH(ifp, &ifnet, int_list) {
832 /* Skip interfaces not doing RIP.
833 * Do try broken interfaces to see if they have healed.
834 */
835 if (IS_RIP_OUT_OFF(ifp->int_state))
836 continue;
837
838 /* skip turned off interfaces */
839 if (!iff_up(ifp->int_if_flags))
840 continue;
841
842 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1;
843
844 if (ifp->int_if_flags & IFF_BROADCAST) {
845 /* ordinary, hardware interface */
846 dst.sin_addr.s_addr = ifp->int_brdaddr;
847
848 if (vers == RIPv2
849 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
850 type = OUT_MULTICAST;
851 } else {
852 type = OUT_BROADCAST;
853 }
854
855 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
856 /* point-to-point hardware interface */
857 dst.sin_addr.s_addr = ifp->int_dstaddr;
858 if (vers == RIPv2 &&
859 ifp->int_if_flags & IFF_MULTICAST &&
860 !(ifp->int_state & IS_NO_RIP_MCAST)) {
861 type = OUT_MULTICAST;
862 } else {
863 type = OUT_UNICAST;
864 }
865
866 } else if (ifp->int_state & IS_REMOTE) {
867 /* remote interface */
868 dst.sin_addr.s_addr = ifp->int_addr;
869 type = OUT_UNICAST;
870
871 } else {
872 /* ATM, HIPPI, etc. */
873 continue;
874 }
875
876 supply(&dst, ifp, type, flash, vers, 1);
877 }
878
879 update_seqno++; /* all routes are up to date */
880 }
881
882
883 /* Ask for routes
884 * Do it only once to an interface, and not even after the interface
885 * was broken and recovered.
886 */
887 void
rip_query(void)888 rip_query(void)
889 {
890 #ifdef _HAVE_SIN_LEN
891 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
892 #else
893 static struct sockaddr_in dst = {AF_INET};
894 #endif
895 struct interface *ifp;
896 struct rip buf;
897 enum output_type type;
898
899
900 if (rip_sock < 0)
901 return;
902
903 memset(&buf, 0, sizeof(buf));
904
905 LIST_FOREACH(ifp, &ifnet, int_list) {
906 /* Skip interfaces those already queried.
907 * Do not ask via interfaces through which we don't
908 * accept input. Do not ask via interfaces that cannot
909 * send RIP packets.
910 * Do try broken interfaces to see if they have healed.
911 */
912 if (IS_RIP_IN_OFF(ifp->int_state)
913 || ifp->int_query_time != NEVER)
914 continue;
915
916 /* skip turned off interfaces */
917 if (!iff_up(ifp->int_if_flags))
918 continue;
919
920 buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1;
921 buf.rip_cmd = RIPCMD_REQUEST;
922 buf.rip_nets[0].n_family = RIP_AF_UNSPEC;
923 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY);
924
925 /* Send a RIPv1 query only if allowed and if we will
926 * listen to RIPv1 routers.
927 */
928 if ((ifp->int_state & IS_NO_RIPV1_OUT)
929 || (ifp->int_state & IS_NO_RIPV1_IN)) {
930 buf.rip_vers = RIPv2;
931 } else {
932 buf.rip_vers = RIPv1;
933 }
934
935 if (ifp->int_if_flags & IFF_BROADCAST) {
936 /* ordinary, hardware interface */
937 dst.sin_addr.s_addr = ifp->int_brdaddr;
938
939 /* Broadcast RIPv1 queries and RIPv2 queries
940 * when the hardware cannot multicast.
941 */
942 if (buf.rip_vers == RIPv2
943 && (ifp->int_if_flags & IFF_MULTICAST)
944 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
945 type = OUT_MULTICAST;
946 } else {
947 type = OUT_BROADCAST;
948 }
949
950 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
951 /* point-to-point hardware interface */
952 dst.sin_addr.s_addr = ifp->int_dstaddr;
953 type = OUT_UNICAST;
954
955 } else if (ifp->int_state & IS_REMOTE) {
956 /* remote interface */
957 dst.sin_addr.s_addr = ifp->int_addr;
958 type = OUT_UNICAST;
959
960 } else {
961 /* ATM, HIPPI, etc. */
962 continue;
963 }
964
965 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL;
966 if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0)
967 if_sick(ifp);
968 }
969 }
970