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 #ifdef __NetBSD__
37 __RCSID("$NetBSD$");
38 #elif defined(__FreeBSD__)
39 __RCSID("$FreeBSD$");
40 #else
41 __RCSID("$Revision: 2.27 $");
42 #ident "$Revision: 2.27 $"
43 #endif
44
45
46 u_int update_seqno;
47
48
49 /* walk the tree of routes with this for output
50 */
51 static struct {
52 struct sockaddr_in to;
53 naddr to_mask;
54 naddr to_net;
55 naddr to_std_mask;
56 naddr to_std_net;
57 struct interface *ifp; /* usually output interface */
58 struct auth *a;
59 char metric; /* adjust metrics by interface */
60 int npackets;
61 int gen_limit;
62 u_int state;
63 #define WS_ST_FLASH 0x001 /* send only changed routes */
64 #define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */
65 #define WS_ST_AG 0x004 /* ok to aggregate subnets */
66 #define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */
67 #define WS_ST_QUERY 0x010 /* responding to a query */
68 #define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */
69 #define WS_ST_DEFAULT 0x040 /* faking a default */
70 } ws;
71
72 /* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */
73 struct ws_buf v12buf;
74 static union pkt_buf ripv12_buf;
75
76 /* Another for only RIPv2 listeners */
77 static struct ws_buf v2buf;
78 static union pkt_buf rip_v2_buf;
79
80
81
82 void
bufinit(void)83 bufinit(void)
84 {
85 ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE;
86 v12buf.buf = &ripv12_buf.rip;
87 v12buf.base = &v12buf.buf->rip_nets[0];
88
89 rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE;
90 rip_v2_buf.rip.rip_vers = RIPv2;
91 v2buf.buf = &rip_v2_buf.rip;
92 v2buf.base = &v2buf.buf->rip_nets[0];
93 }
94
95
96 /* Send the contents of the global buffer via the non-multicast socket
97 */
98 int /* <0 on failure */
output(enum output_type type,struct sockaddr_in * dst,struct interface * ifp,struct rip * buf,int size)99 output(enum output_type type,
100 struct sockaddr_in *dst, /* send to here */
101 struct interface *ifp,
102 struct rip *buf,
103 int size) /* this many bytes */
104 {
105 struct sockaddr_in osin;
106 int flags;
107 const char *msg;
108 int res;
109 int soc;
110 int serrno;
111
112 assert(ifp != NULL);
113 osin = *dst;
114 if (osin.sin_port == 0)
115 osin.sin_port = htons(RIP_PORT);
116 #ifdef _HAVE_SIN_LEN
117 if (osin.sin_len == 0)
118 osin.sin_len = sizeof(osin);
119 #endif
120
121 soc = rip_sock;
122 flags = 0;
123
124 switch (type) {
125 case OUT_QUERY:
126 msg = "Answer Query";
127 if (soc < 0)
128 soc = ifp->int_rip_sock;
129 break;
130 case OUT_UNICAST:
131 msg = "Send";
132 if (soc < 0)
133 soc = ifp->int_rip_sock;
134 flags = MSG_DONTROUTE;
135 break;
136 case OUT_BROADCAST:
137 if (ifp->int_if_flags & IFF_POINTOPOINT) {
138 msg = "Send";
139 } else {
140 msg = "Send bcast";
141 }
142 flags = MSG_DONTROUTE;
143 break;
144 case OUT_MULTICAST:
145 if ((ifp->int_if_flags & (IFF_POINTOPOINT|IFF_MULTICAST)) ==
146 IFF_POINTOPOINT) {
147 msg = "Send pt-to-pt";
148 } else if (ifp->int_state & IS_DUP) {
149 trace_act("abort multicast output via %s"
150 " with duplicate address",
151 ifp->int_name);
152 return 0;
153 } else {
154 msg = "Send mcast";
155 if (rip_sock_mcast != ifp) {
156 struct ip_mreqn mreqn;
157
158 memset(&mreqn, 0, sizeof(struct ip_mreqn));
159 mreqn.imr_ifindex = ifp->int_index;
160 if (0 > setsockopt(rip_sock,
161 IPPROTO_IP,
162 IP_MULTICAST_IF,
163 &mreqn,
164 sizeof(mreqn))) {
165 serrno = errno;
166 LOGERR("setsockopt(rip_sock, "
167 "IP_MULTICAST_IF)");
168 errno = serrno;
169 ifp = NULL;
170 return -1;
171 }
172 rip_sock_mcast = ifp;
173 }
174 osin.sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
175 }
176 break;
177
178 case NO_OUT_MULTICAST:
179 case NO_OUT_RIPV2:
180 default:
181 #ifdef DEBUG
182 abort();
183 #endif
184 return -1;
185 }
186
187 trace_rip(msg, "to", &osin, ifp, buf, size);
188
189 res = sendto(soc, buf, size, flags,
190 (struct sockaddr *)&osin, sizeof(osin));
191 if (res < 0
192 && (ifp == NULL || !(ifp->int_state & IS_BROKE))) {
193 serrno = errno;
194 msglog("%s sendto(%s%s%s.%d): %s", msg,
195 ifp != NULL ? ifp->int_name : "",
196 ifp != NULL ? ", " : "",
197 inet_ntoa(osin.sin_addr),
198 ntohs(osin.sin_port),
199 strerror(errno));
200 errno = serrno;
201 }
202
203 return res;
204 }
205
206
207 /* Find the first key for a packet to send.
208 * Try for a key that is eligible and has not expired, but settle for
209 * the last key if they have all expired.
210 * If no key is ready yet, give up.
211 */
212 struct auth *
find_auth(struct interface * ifp)213 find_auth(struct interface *ifp)
214 {
215 struct auth *ap, *res;
216 int i;
217
218
219 if (ifp == NULL)
220 return 0;
221
222 res = NULL;
223 ap = ifp->int_auth;
224 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) {
225 /* stop looking after the last key */
226 if (ap->type == RIP_AUTH_NONE)
227 break;
228
229 /* ignore keys that are not ready yet */
230 if ((u_long)ap->start > (u_long)clk.tv_sec)
231 continue;
232
233 if ((u_long)ap->end < (u_long)clk.tv_sec) {
234 /* note best expired password as a fall-back */
235 if (res == NULL || (u_long)ap->end > (u_long)res->end)
236 res = ap;
237 continue;
238 }
239
240 /* note key with the best future */
241 if (res == NULL || (u_long)res->end < (u_long)ap->end)
242 res = ap;
243 }
244 return res;
245 }
246
247
248 void
clr_ws_buf(struct ws_buf * wb,struct auth * ap)249 clr_ws_buf(struct ws_buf *wb,
250 struct auth *ap)
251 {
252 struct netauth *na;
253
254 wb->lim = wb->base + NETS_LEN;
255 wb->n = wb->base;
256 memset(wb->n, 0, NETS_LEN*sizeof(*wb->n));
257
258 /* (start to) install authentication if appropriate
259 */
260 if (ap == NULL)
261 return;
262
263 na = (struct netauth*)wb->n;
264 if (ap->type == RIP_AUTH_PW) {
265 na->a_family = RIP_AF_AUTH;
266 na->a_type = RIP_AUTH_PW;
267 memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw));
268 wb->n++;
269
270 } else if (ap->type == RIP_AUTH_MD5) {
271 na->a_family = RIP_AF_AUTH;
272 na->a_type = RIP_AUTH_MD5;
273 na->au.a_md5.md5_keyid = ap->keyid;
274 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_KEY_LEN;
275 na->au.a_md5.md5_seqno = htonl(clk.tv_sec);
276 wb->n++;
277 wb->lim--; /* make room for trailer */
278 }
279 }
280
281
282 void
end_md5_auth(struct ws_buf * wb,struct auth * ap)283 end_md5_auth(struct ws_buf *wb,
284 struct auth *ap)
285 {
286 struct netauth *na, *na2;
287 MD5_CTX md5_ctx;
288 int len;
289
290
291 na = (struct netauth*)wb->base;
292 na2 = (struct netauth*)wb->n;
293 len = (char *)na2-(char *)wb->buf;
294 na2->a_family = RIP_AF_AUTH;
295 na2->a_type = htons(1);
296 na->au.a_md5.md5_pkt_len = htons(len);
297 MD5Init(&md5_ctx);
298 MD5Update(&md5_ctx, (u_char *)wb->buf, len + RIP_AUTH_MD5_HASH_XTRA);
299 MD5Update(&md5_ctx, ap->key, RIP_AUTH_MD5_KEY_LEN);
300 MD5Final(na2->au.au_pw, &md5_ctx);
301 wb->n++;
302 }
303
304
305 /* Send the buffer
306 */
307 static void
supply_write(struct ws_buf * wb)308 supply_write(struct ws_buf *wb)
309 {
310 /* Output multicast only if legal.
311 * If we would multicast and it would be illegal, then discard the
312 * packet.
313 */
314 switch (wb->type) {
315 case NO_OUT_MULTICAST:
316 trace_pkt("skip multicast to %s because impossible",
317 naddr_ntoa(ws.to.sin_addr.s_addr));
318 break;
319 case NO_OUT_RIPV2:
320 break;
321 default:
322 if (ws.a != NULL && ws.a->type == RIP_AUTH_MD5)
323 end_md5_auth(wb,ws.a);
324 if (output(wb->type, &ws.to, ws.ifp, wb->buf,
325 ((char *)wb->n - (char*)wb->buf)) < 0
326 && ws.ifp != NULL)
327 if_sick(ws.ifp);
328 ws.npackets++;
329 break;
330 }
331
332 clr_ws_buf(wb,ws.a);
333 }
334
335
336 /* put an entry into the packet
337 */
338 static void
supply_out(struct ag_info * ag)339 supply_out(struct ag_info *ag)
340 {
341 int i;
342 naddr mask, v1_mask, dst_h, ddst_h = 0;
343 struct ws_buf *wb;
344
345
346 /* Skip this route if doing a flash update and it and the routes
347 * it aggregates have not changed recently.
348 */
349 if (ag->ag_seqno < update_seqno
350 && (ws.state & WS_ST_FLASH))
351 return;
352
353 dst_h = ag->ag_dst_h;
354 mask = ag->ag_mask;
355 v1_mask = ripv1_mask_host(htonl(dst_h),
356 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0);
357 i = 0;
358
359 /* If we are sending RIPv2 packets that cannot (or must not) be
360 * heard by RIPv1 listeners, do not worry about sub- or supernets.
361 * Subnets (from other networks) can only be sent via multicast.
362 * A pair of subnet routes might have been promoted so that they
363 * are legal to send by RIPv1.
364 * If RIPv1 is off, use the multicast buffer.
365 */
366 if ((ws.state & WS_ST_RIP2_ALL)
367 || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) {
368 /* use the RIPv2-only buffer */
369 wb = &v2buf;
370
371 } else {
372 /* use the RIPv1-or-RIPv2 buffer */
373 wb = &v12buf;
374
375 /* Convert supernet route into corresponding set of network
376 * routes for RIPv1, but leave non-contiguous netmasks
377 * to ag_check().
378 */
379 if (v1_mask > mask
380 && mask + (mask & -mask) == 0) {
381 ddst_h = v1_mask & -v1_mask;
382 i = (v1_mask & ~mask)/ddst_h;
383
384 if (i > ws.gen_limit) {
385 /* Punt if we would have to generate an
386 * unreasonable number of routes.
387 */
388 if (TRACECONTENTS)
389 trace_misc("sending %s-->%s as 1"
390 " instead of %d routes",
391 addrname(htonl(dst_h), mask,
392 1),
393 naddr_ntoa(ws.to.sin_addr
394 .s_addr),
395 i+1);
396 i = 0;
397
398 } else {
399 mask = v1_mask;
400 ws.gen_limit -= i;
401 }
402 }
403 }
404
405 do {
406 wb->n->n_family = RIP_AF_INET;
407 wb->n->n_dst = htonl(dst_h);
408 /* If the route is from router-discovery or we are
409 * shutting down, admit only a bad metric.
410 */
411 wb->n->n_metric = ((stopint || ag->ag_metric < 1)
412 ? HOPCNT_INFINITY
413 : ag->ag_metric);
414 wb->n->n_metric = htonl(wb->n->n_metric);
415 /* Any non-zero bits in the supposedly unused RIPv1 fields
416 * cause the old `routed` to ignore the route.
417 * That means the mask and so forth cannot be sent
418 * in the hybrid RIPv1/RIPv2 mode.
419 */
420 if (ws.state & WS_ST_RIP2_ALL) {
421 if (ag->ag_nhop != 0
422 && ((ws.state & WS_ST_QUERY)
423 || (ag->ag_nhop != ws.ifp->int_addr
424 && on_net(ag->ag_nhop,
425 ws.ifp->int_net,
426 ws.ifp->int_mask))))
427 wb->n->n_nhop = ag->ag_nhop;
428 wb->n->n_mask = htonl(mask);
429 wb->n->n_tag = ag->ag_tag;
430 }
431 dst_h += ddst_h;
432
433 if (++wb->n >= wb->lim)
434 supply_write(wb);
435 } while (i-- != 0);
436 }
437
438
439 /* supply one route from the table
440 */
441 /* ARGSUSED */
442 static int
walk_supply(struct radix_node * rn,struct walkarg * argp UNUSED)443 walk_supply(struct radix_node *rn,
444 struct walkarg *argp UNUSED)
445 {
446 #define RT ((struct rt_entry *)rn)
447 u_short ags;
448 char metric, pref;
449 naddr dst, nhop;
450 struct rt_spare *rts;
451 int i;
452
453
454 /* Do not advertise external remote interfaces or passive interfaces.
455 */
456 if ((RT->rt_state & RS_IF)
457 && RT->rt_ifp != 0
458 && (RT->rt_ifp->int_state & IS_PASSIVE)
459 && !(RT->rt_state & RS_MHOME))
460 return 0;
461
462 /* If being quiet about our ability to forward, then
463 * do not say anything unless responding to a query,
464 * except about our main interface.
465 */
466 if (!supplier && !(ws.state & WS_ST_QUERY)
467 && !(RT->rt_state & RS_MHOME))
468 return 0;
469
470 dst = RT->rt_dst;
471
472 /* do not collide with the fake default route */
473 if (dst == RIP_DEFAULT
474 && (ws.state & WS_ST_DEFAULT))
475 return 0;
476
477 if (RT->rt_state & RS_NET_SYN) {
478 if (RT->rt_state & RS_NET_INT) {
479 /* Do not send manual synthetic network routes
480 * into the subnet.
481 */
482 if (on_net(ws.to.sin_addr.s_addr,
483 ntohl(dst), RT->rt_mask))
484 return 0;
485
486 } else {
487 /* Do not send automatic synthetic network routes
488 * if they are not needed because no RIPv1 listeners
489 * can hear them.
490 */
491 if (ws.state & WS_ST_RIP2_ALL)
492 return 0;
493
494 /* Do not send automatic synthetic network routes to
495 * the real subnet.
496 */
497 if (on_net(ws.to.sin_addr.s_addr,
498 ntohl(dst), RT->rt_mask))
499 return 0;
500 }
501 nhop = 0;
502
503 } else {
504 /* Advertise the next hop if this is not a route for one
505 * of our interfaces and the next hop is on the same
506 * network as the target.
507 * The final determination is made by supply_out().
508 */
509 if (!(RT->rt_state & RS_IF)
510 && RT->rt_gate != myaddr
511 && RT->rt_gate != loopaddr)
512 nhop = RT->rt_gate;
513 else
514 nhop = 0;
515 }
516
517 metric = RT->rt_metric;
518 ags = 0;
519
520 if (RT->rt_state & RS_MHOME) {
521 /* retain host route of multi-homed servers */
522 ;
523
524 } else if (RT_ISHOST(RT)) {
525 /* We should always suppress (into existing network routes)
526 * the host routes for the local end of our point-to-point
527 * links.
528 * If we are suppressing host routes in general, then do so.
529 * Avoid advertising host routes onto their own network,
530 * where they should be handled by proxy-ARP.
531 */
532 if ((RT->rt_state & RS_LOCAL)
533 || ridhosts
534 || on_net(dst, ws.to_net, ws.to_mask))
535 ags |= AGS_SUPPRESS;
536
537 /* Aggregate stray host routes into network routes if allowed.
538 * We cannot aggregate host routes into small network routes
539 * without confusing RIPv1 listeners into thinking the
540 * network routes are host routes.
541 */
542 if ((ws.state & WS_ST_AG) && (ws.state & WS_ST_RIP2_ALL))
543 ags |= AGS_AGGREGATE;
544
545 } else {
546 /* Always suppress network routes into other, existing
547 * network routes
548 */
549 ags |= AGS_SUPPRESS;
550
551 /* Generate supernets if allowed.
552 * If we can be heard by RIPv1 systems, we will
553 * later convert back to ordinary nets.
554 * This unifies dealing with received supernets.
555 */
556 if ((ws.state & WS_ST_AG)
557 && ((RT->rt_state & RS_SUBNET)
558 || (ws.state & WS_ST_SUPER_AG)))
559 ags |= AGS_AGGREGATE;
560 }
561
562 /* Do not send RIPv1 advertisements of subnets to other
563 * networks. If possible, multicast them by RIPv2.
564 */
565 if ((RT->rt_state & RS_SUBNET)
566 && !(ws.state & WS_ST_RIP2_ALL)
567 && !on_net(dst, ws.to_std_net, ws.to_std_mask))
568 ags |= AGS_RIPV2 | AGS_AGGREGATE;
569
570
571 /* Do not send a route back to where it came from, except in
572 * response to a query. This is "split-horizon". That means not
573 * advertising back to the same network and so via the same interface.
574 *
575 * We want to suppress routes that might have been fragmented
576 * from this route by a RIPv1 router and sent back to us, and so we
577 * cannot forget this route here. Let the split-horizon route
578 * suppress the fragmented routes and then itself be forgotten.
579 *
580 * Include the routes for both ends of point-to-point interfaces
581 * among those suppressed by split-horizon, since the other side
582 * should knows them as well as we do.
583 *
584 * Notice spare routes with the same metric that we are about to
585 * advertise, to split the horizon on redundant, inactive paths.
586 *
587 * Do not suppress advertisements of interface-related addresses on
588 * non-point-to-point interfaces. This ensures that we have something
589 * to say every 30 seconds to help detect broken Ethernets or
590 * other interfaces where one packet every 30 seconds costs nothing.
591 */
592 if (ws.ifp != NULL
593 && !(ws.state & WS_ST_QUERY)
594 && (ws.state & WS_ST_TO_ON_NET)
595 && (!(RT->rt_state & RS_IF)
596 || ws.ifp->int_if_flags & IFF_POINTOPOINT)) {
597 for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) {
598 if (rts->rts_metric > metric
599 || rts->rts_ifp != ws.ifp)
600 continue;
601
602 /* If we do not mark the route with AGS_SPLIT_HZ here,
603 * it will be poisoned-reverse, or advertised back
604 * toward its source with an infinite metric.
605 * If we have recently advertised the route with a
606 * better metric than we now have, then we should
607 * poison-reverse the route before suppressing it for
608 * split-horizon.
609 *
610 * In almost all cases, if there is no spare for the
611 * route then it is either old and dead or a brand
612 * new route. If it is brand new, there is no need
613 * for poison-reverse. If it is old and dead, it
614 * is already poisoned.
615 */
616 if (RT->rt_poison_time < now_expire
617 || RT->rt_poison_metric >= metric
618 || RT->rt_spares[1].rts_gate == 0) {
619 ags |= AGS_SPLIT_HZ;
620 ags &= ~AGS_SUPPRESS;
621 }
622 metric = HOPCNT_INFINITY;
623 break;
624 }
625 }
626
627 /* Keep track of the best metric with which the
628 * route has been advertised recently.
629 */
630 if (RT->rt_poison_metric >= metric
631 || RT->rt_poison_time < now_expire) {
632 RT->rt_poison_time = now.tv_sec;
633 RT->rt_poison_metric = metric;
634 }
635
636 /* Adjust the outgoing metric by the cost of the link.
637 * Avoid aggregation when a route is counting to infinity.
638 */
639 pref = RT->rt_poison_metric + ws.metric;
640 metric += ws.metric;
641
642 /* Do not advertise stable routes that will be ignored,
643 * unless we are answering a query.
644 * If the route recently was advertised with a metric that
645 * would have been less than infinity through this interface,
646 * we need to continue to advertise it in order to poison it.
647 */
648 if (metric >= HOPCNT_INFINITY) {
649 if (!(ws.state & WS_ST_QUERY)
650 && (pref >= HOPCNT_INFINITY
651 || RT->rt_poison_time < now_garbage))
652 return 0;
653
654 metric = HOPCNT_INFINITY;
655 }
656
657 ag_check(dst, RT->rt_mask, 0, nhop, metric, pref,
658 RT->rt_seqno, RT->rt_tag, ags, supply_out);
659 return 0;
660 #undef RT
661 }
662
663
664 /* Supply dst with the contents of the routing tables.
665 * If this won't fit in one packet, chop it up into several.
666 */
667 void
supply(struct sockaddr_in * dst,struct interface * ifp,enum output_type type,int flash,int vers,int passwd_ok)668 supply(struct sockaddr_in *dst,
669 struct interface *ifp, /* output interface */
670 enum output_type type,
671 int flash, /* 1=flash update */
672 int vers, /* RIP version */
673 int passwd_ok) /* OK to include cleartext password */
674 {
675 struct rt_entry *rt;
676 int def_metric;
677
678 ws.state = 0;
679 ws.gen_limit = 1024;
680
681 ws.to = *dst;
682 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr);
683 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask;
684
685 if (ifp != NULL) {
686 ws.to_mask = ifp->int_mask;
687 ws.to_net = ifp->int_net;
688 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask))
689 ws.state |= WS_ST_TO_ON_NET;
690
691 } else {
692 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0);
693 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask;
694 rt = rtfind(dst->sin_addr.s_addr);
695 if (rt)
696 ifp = rt->rt_ifp;
697 }
698
699 ws.npackets = 0;
700 if (flash)
701 ws.state |= WS_ST_FLASH;
702
703 if ((ws.ifp = ifp) == NULL) {
704 ws.metric = 1;
705 } else {
706 /* Adjust the advertised metric by the outgoing interface
707 * metric.
708 */
709 ws.metric = ifp->int_metric + 1 + ifp->int_adj_outmetric;
710 }
711
712 ripv12_buf.rip.rip_vers = vers;
713
714 switch (type) {
715 case OUT_MULTICAST:
716 if (ifp != NULL && ifp->int_if_flags & IFF_MULTICAST)
717 v2buf.type = OUT_MULTICAST;
718 else
719 v2buf.type = NO_OUT_MULTICAST;
720 v12buf.type = OUT_BROADCAST;
721 break;
722
723 case OUT_QUERY:
724 ws.state |= WS_ST_QUERY;
725 /* FALLTHROUGH */
726 case OUT_BROADCAST:
727 case OUT_UNICAST:
728 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2;
729 v12buf.type = type;
730 break;
731
732 case NO_OUT_MULTICAST:
733 case NO_OUT_RIPV2:
734 break; /* no output */
735 }
736
737 if (vers == RIPv2) {
738 /* full RIPv2 only if cannot be heard by RIPv1 listeners */
739 if (type != OUT_BROADCAST)
740 ws.state |= WS_ST_RIP2_ALL;
741 if ((ws.state & WS_ST_QUERY)
742 || !(ws.state & WS_ST_TO_ON_NET)) {
743 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG);
744 } else if (ifp == NULL || !(ifp->int_state & IS_NO_AG)) {
745 ws.state |= WS_ST_AG;
746 if (type != OUT_BROADCAST
747 && (ifp == NULL
748 || !(ifp->int_state & IS_NO_SUPER_AG)))
749 ws.state |= WS_ST_SUPER_AG;
750 }
751 }
752
753 ws.a = (vers == RIPv2) ? find_auth(ifp) : 0;
754 if (!passwd_ok && ws.a != NULL && ws.a->type == RIP_AUTH_PW)
755 ws.a = NULL;
756 clr_ws_buf(&v12buf,ws.a);
757 clr_ws_buf(&v2buf,ws.a);
758
759 /* Fake a default route if asked and if there is not already
760 * a better, real default route.
761 */
762 if (supplier && ifp && (def_metric = ifp->int_d_metric) != 0) {
763 if ((rt = rtget(RIP_DEFAULT, 0)) == NULL
764 || rt->rt_metric+ws.metric >= def_metric) {
765 ws.state |= WS_ST_DEFAULT;
766 ag_check(0, 0, 0, 0, def_metric, def_metric,
767 0, 0, 0, supply_out);
768 } else {
769 def_metric = rt->rt_metric+ws.metric;
770 }
771
772 /* If both RIPv2 and the poor-man's router discovery
773 * kludge are on, arrange to advertise an extra
774 * default route via RIPv1.
775 */
776 if ((ws.state & WS_ST_RIP2_ALL)
777 && (ifp->int_state & IS_PM_RDISC)) {
778 ripv12_buf.rip.rip_vers = RIPv1;
779 v12buf.n->n_family = RIP_AF_INET;
780 v12buf.n->n_dst = htonl(RIP_DEFAULT);
781 v12buf.n->n_metric = htonl(def_metric);
782 v12buf.n++;
783 }
784 }
785
786 (void)rn_walktree(rhead, walk_supply, 0);
787 ag_flush(0,0,supply_out);
788
789 /* Flush the packet buffers, provided they are not empty and
790 * do not contain only the password.
791 */
792 if (v12buf.n != v12buf.base
793 && (v12buf.n > v12buf.base+1
794 || v12buf.base->n_family != RIP_AF_AUTH))
795 supply_write(&v12buf);
796 if (v2buf.n != v2buf.base
797 && (v2buf.n > v2buf.base+1
798 || v2buf.base->n_family != RIP_AF_AUTH))
799 supply_write(&v2buf);
800
801 /* If we sent nothing and this is an answer to a query, send
802 * an empty buffer.
803 */
804 if (ws.npackets == 0
805 && (ws.state & WS_ST_QUERY))
806 supply_write(&v12buf);
807 }
808
809
810 /* send all of the routing table or just do a flash update
811 */
812 void
rip_bcast(int flash)813 rip_bcast(int flash)
814 {
815 #ifdef _HAVE_SIN_LEN
816 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
817 #else
818 static struct sockaddr_in dst = {AF_INET};
819 #endif
820 struct interface *ifp;
821 enum output_type type;
822 int vers;
823 struct timeval rtime;
824
825
826 need_flash = 0;
827 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME);
828 no_flash = rtime;
829 timevaladd(&no_flash, &now);
830
831 if (rip_sock < 0)
832 return;
833
834 trace_act("send %s and inhibit dynamic updates for %.3f sec",
835 flash ? "dynamic update" : "all routes",
836 rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0);
837
838 LIST_FOREACH(ifp, &ifnet, int_list) {
839 /* Skip interfaces not doing RIP.
840 * Do try broken interfaces to see if they have healed.
841 */
842 if (IS_RIP_OUT_OFF(ifp->int_state))
843 continue;
844
845 /* skip turned off interfaces */
846 if (!iff_up(ifp->int_if_flags))
847 continue;
848
849 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1;
850
851 if (ifp->int_if_flags & IFF_BROADCAST) {
852 /* ordinary, hardware interface */
853 dst.sin_addr.s_addr = ifp->int_brdaddr;
854
855 if (vers == RIPv2
856 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
857 type = OUT_MULTICAST;
858 } else {
859 type = OUT_BROADCAST;
860 }
861
862 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
863 /* point-to-point hardware interface */
864 dst.sin_addr.s_addr = ifp->int_dstaddr;
865 if (vers == RIPv2 &&
866 ifp->int_if_flags & IFF_MULTICAST &&
867 !(ifp->int_state & IS_NO_RIP_MCAST)) {
868 type = OUT_MULTICAST;
869 } else {
870 type = OUT_UNICAST;
871 }
872
873 } else if (ifp->int_state & IS_REMOTE) {
874 /* remote interface */
875 dst.sin_addr.s_addr = ifp->int_addr;
876 type = OUT_UNICAST;
877
878 } else {
879 /* ATM, HIPPI, etc. */
880 continue;
881 }
882
883 supply(&dst, ifp, type, flash, vers, 1);
884 }
885
886 update_seqno++; /* all routes are up to date */
887 }
888
889
890 /* Ask for routes
891 * Do it only once to an interface, and not even after the interface
892 * was broken and recovered.
893 */
894 void
rip_query(void)895 rip_query(void)
896 {
897 #ifdef _HAVE_SIN_LEN
898 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
899 #else
900 static struct sockaddr_in dst = {AF_INET};
901 #endif
902 struct interface *ifp;
903 struct rip buf;
904 enum output_type type;
905
906
907 if (rip_sock < 0)
908 return;
909
910 memset(&buf, 0, sizeof(buf));
911
912 LIST_FOREACH(ifp, &ifnet, int_list) {
913 /* Skip interfaces those already queried.
914 * Do not ask via interfaces through which we don't
915 * accept input. Do not ask via interfaces that cannot
916 * send RIP packets.
917 * Do try broken interfaces to see if they have healed.
918 */
919 if (IS_RIP_IN_OFF(ifp->int_state)
920 || ifp->int_query_time != NEVER)
921 continue;
922
923 /* skip turned off interfaces */
924 if (!iff_up(ifp->int_if_flags))
925 continue;
926
927 buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1;
928 buf.rip_cmd = RIPCMD_REQUEST;
929 buf.rip_nets[0].n_family = RIP_AF_UNSPEC;
930 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY);
931
932 /* Send a RIPv1 query only if allowed and if we will
933 * listen to RIPv1 routers.
934 */
935 if ((ifp->int_state & IS_NO_RIPV1_OUT)
936 || (ifp->int_state & IS_NO_RIPV1_IN)) {
937 buf.rip_vers = RIPv2;
938 } else {
939 buf.rip_vers = RIPv1;
940 }
941
942 if (ifp->int_if_flags & IFF_BROADCAST) {
943 /* ordinary, hardware interface */
944 dst.sin_addr.s_addr = ifp->int_brdaddr;
945
946 /* Broadcast RIPv1 queries and RIPv2 queries
947 * when the hardware cannot multicast.
948 */
949 if (buf.rip_vers == RIPv2
950 && (ifp->int_if_flags & IFF_MULTICAST)
951 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
952 type = OUT_MULTICAST;
953 } else {
954 type = OUT_BROADCAST;
955 }
956
957 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
958 /* point-to-point hardware interface */
959 dst.sin_addr.s_addr = ifp->int_dstaddr;
960 type = OUT_UNICAST;
961
962 } else if (ifp->int_state & IS_REMOTE) {
963 /* remote interface */
964 dst.sin_addr.s_addr = ifp->int_addr;
965 type = OUT_UNICAST;
966
967 } else {
968 /* ATM, HIPPI, etc. */
969 continue;
970 }
971
972 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL;
973 if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0)
974 if_sick(ifp);
975 }
976 }
977