1 /*
2 * Copyright (c) 1983, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31
32 #include "defs.h"
33
34 #ifdef __NetBSD__
35 __RCSID("$NetBSD$");
36 #elif defined(__FreeBSD__)
37 __RCSID("$FreeBSD$");
38 #else
39 __RCSID("$Revision: 2.27 $");
40 #ident "$Revision: 2.27 $"
41 #endif
42
43
44 u_int update_seqno;
45
46
47 /* walk the tree of routes with this for output
48 */
49 static struct {
50 struct sockaddr_in to;
51 naddr to_mask;
52 naddr to_net;
53 naddr to_std_mask;
54 naddr to_std_net;
55 struct interface *ifp; /* usually output interface */
56 struct auth *a;
57 char metric; /* adjust metrics by interface */
58 int npackets;
59 int gen_limit;
60 u_int state;
61 #define WS_ST_FLASH 0x001 /* send only changed routes */
62 #define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */
63 #define WS_ST_AG 0x004 /* ok to aggregate subnets */
64 #define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */
65 #define WS_ST_QUERY 0x010 /* responding to a query */
66 #define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */
67 #define WS_ST_DEFAULT 0x040 /* faking a default */
68 } ws;
69
70 /* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */
71 struct ws_buf v12buf;
72 static union pkt_buf ripv12_buf;
73
74 /* Another for only RIPv2 listeners */
75 static struct ws_buf v2buf;
76 static union pkt_buf rip_v2_buf;
77
78
79
80 void
bufinit(void)81 bufinit(void)
82 {
83 ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE;
84 v12buf.buf = &ripv12_buf.rip;
85 v12buf.base = &v12buf.buf->rip_nets[0];
86
87 rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE;
88 rip_v2_buf.rip.rip_vers = RIPv2;
89 v2buf.buf = &rip_v2_buf.rip;
90 v2buf.base = &v2buf.buf->rip_nets[0];
91 }
92
93
94 /* Send the contents of the global buffer via the non-multicast socket
95 */
96 int /* <0 on failure */
output(enum output_type type,struct sockaddr_in * dst,struct interface * ifp,struct rip * buf,int size)97 output(enum output_type type,
98 struct sockaddr_in *dst, /* send to here */
99 struct interface *ifp,
100 struct rip *buf,
101 int size) /* this many bytes */
102 {
103 struct sockaddr_in osin;
104 int flags;
105 const char *msg;
106 int res;
107 int soc;
108 int serrno;
109
110 assert(ifp != NULL);
111 osin = *dst;
112 if (osin.sin_port == 0)
113 osin.sin_port = htons(RIP_PORT);
114 #ifdef _HAVE_SIN_LEN
115 if (osin.sin_len == 0)
116 osin.sin_len = sizeof(osin);
117 #endif
118
119 soc = rip_sock;
120 flags = 0;
121
122 switch (type) {
123 case OUT_QUERY:
124 msg = "Answer Query";
125 if (soc < 0)
126 soc = ifp->int_rip_sock;
127 break;
128 case OUT_UNICAST:
129 msg = "Send";
130 if (soc < 0)
131 soc = ifp->int_rip_sock;
132 flags = MSG_DONTROUTE;
133 break;
134 case OUT_BROADCAST:
135 if (ifp->int_if_flags & IFF_POINTOPOINT) {
136 msg = "Send";
137 } else {
138 msg = "Send bcast";
139 }
140 flags = MSG_DONTROUTE;
141 break;
142 case OUT_MULTICAST:
143 if ((ifp->int_if_flags & (IFF_POINTOPOINT|IFF_MULTICAST)) ==
144 IFF_POINTOPOINT) {
145 msg = "Send pt-to-pt";
146 } else if (ifp->int_state & IS_DUP) {
147 trace_act("abort multicast output via %s"
148 " with duplicate address",
149 ifp->int_name);
150 return 0;
151 } else {
152 msg = "Send mcast";
153 if (rip_sock_mcast != ifp) {
154 struct ip_mreqn mreqn;
155
156 memset(&mreqn, 0, sizeof(struct ip_mreqn));
157 mreqn.imr_ifindex = ifp->int_index;
158 if (0 > setsockopt(rip_sock,
159 IPPROTO_IP,
160 IP_MULTICAST_IF,
161 &mreqn,
162 sizeof(mreqn))) {
163 serrno = errno;
164 LOGERR("setsockopt(rip_sock, "
165 "IP_MULTICAST_IF)");
166 errno = serrno;
167 ifp = 0;
168 return -1;
169 }
170 rip_sock_mcast = ifp;
171 }
172 osin.sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
173 }
174 break;
175
176 case NO_OUT_MULTICAST:
177 case NO_OUT_RIPV2:
178 default:
179 #ifdef DEBUG
180 abort();
181 #endif
182 return -1;
183 }
184
185 trace_rip(msg, "to", &osin, ifp, buf, size);
186
187 res = sendto(soc, buf, size, flags,
188 (struct sockaddr *)&osin, sizeof(osin));
189 if (res < 0
190 && (ifp == 0 || !(ifp->int_state & IS_BROKE))) {
191 serrno = errno;
192 msglog("%s sendto(%s%s%s.%d): %s", msg,
193 ifp != 0 ? ifp->int_name : "",
194 ifp != 0 ? ", " : "",
195 inet_ntoa(osin.sin_addr),
196 ntohs(osin.sin_port),
197 strerror(errno));
198 errno = serrno;
199 }
200
201 return res;
202 }
203
204
205 /* Find the first key for a packet to send.
206 * Try for a key that is eligible and has not expired, but settle for
207 * the last key if they have all expired.
208 * If no key is ready yet, give up.
209 */
210 struct auth *
find_auth(struct interface * ifp)211 find_auth(struct interface *ifp)
212 {
213 struct auth *ap, *res;
214 int i;
215
216
217 if (ifp == 0)
218 return 0;
219
220 res = 0;
221 ap = ifp->int_auth;
222 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) {
223 /* stop looking after the last key */
224 if (ap->type == RIP_AUTH_NONE)
225 break;
226
227 /* ignore keys that are not ready yet */
228 if ((u_long)ap->start > (u_long)clk.tv_sec)
229 continue;
230
231 if ((u_long)ap->end < (u_long)clk.tv_sec) {
232 /* note best expired password as a fall-back */
233 if (res == 0 || (u_long)ap->end > (u_long)res->end)
234 res = ap;
235 continue;
236 }
237
238 /* note key with the best future */
239 if (res == 0 || (u_long)res->end < (u_long)ap->end)
240 res = ap;
241 }
242 return res;
243 }
244
245
246 void
clr_ws_buf(struct ws_buf * wb,struct auth * ap)247 clr_ws_buf(struct ws_buf *wb,
248 struct auth *ap)
249 {
250 struct netauth *na;
251
252 wb->lim = wb->base + NETS_LEN;
253 wb->n = wb->base;
254 memset(wb->n, 0, NETS_LEN*sizeof(*wb->n));
255
256 /* (start to) install authentication if appropriate
257 */
258 if (ap == 0)
259 return;
260
261 na = (struct netauth*)wb->n;
262 if (ap->type == RIP_AUTH_PW) {
263 na->a_family = RIP_AF_AUTH;
264 na->a_type = RIP_AUTH_PW;
265 memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw));
266 wb->n++;
267
268 } else if (ap->type == RIP_AUTH_MD5) {
269 na->a_family = RIP_AF_AUTH;
270 na->a_type = RIP_AUTH_MD5;
271 na->au.a_md5.md5_keyid = ap->keyid;
272 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_KEY_LEN;
273 na->au.a_md5.md5_seqno = htonl(clk.tv_sec);
274 wb->n++;
275 wb->lim--; /* make room for trailer */
276 }
277 }
278
279
280 void
end_md5_auth(struct ws_buf * wb,struct auth * ap)281 end_md5_auth(struct ws_buf *wb,
282 struct auth *ap)
283 {
284 struct netauth *na, *na2;
285 MD5_CTX md5_ctx;
286 int len;
287
288
289 na = (struct netauth*)wb->base;
290 na2 = (struct netauth*)wb->n;
291 len = (char *)na2-(char *)wb->buf;
292 na2->a_family = RIP_AF_AUTH;
293 na2->a_type = htons(1);
294 na->au.a_md5.md5_pkt_len = htons(len);
295 MD5Init(&md5_ctx);
296 MD5Update(&md5_ctx, (u_char *)wb->buf, len + RIP_AUTH_MD5_HASH_XTRA);
297 MD5Update(&md5_ctx, ap->key, RIP_AUTH_MD5_KEY_LEN);
298 MD5Final(na2->au.au_pw, &md5_ctx);
299 wb->n++;
300 }
301
302
303 /* Send the buffer
304 */
305 static void
supply_write(struct ws_buf * wb)306 supply_write(struct ws_buf *wb)
307 {
308 /* Output multicast only if legal.
309 * If we would multicast and it would be illegal, then discard the
310 * packet.
311 */
312 switch (wb->type) {
313 case NO_OUT_MULTICAST:
314 trace_pkt("skip multicast to %s because impossible",
315 naddr_ntoa(ws.to.sin_addr.s_addr));
316 break;
317 case NO_OUT_RIPV2:
318 break;
319 default:
320 if (ws.a != 0 && ws.a->type == RIP_AUTH_MD5)
321 end_md5_auth(wb,ws.a);
322 if (output(wb->type, &ws.to, ws.ifp, wb->buf,
323 ((char *)wb->n - (char*)wb->buf)) < 0
324 && ws.ifp != 0)
325 if_sick(ws.ifp);
326 ws.npackets++;
327 break;
328 }
329
330 clr_ws_buf(wb,ws.a);
331 }
332
333
334 /* put an entry into the packet
335 */
336 static void
supply_out(struct ag_info * ag)337 supply_out(struct ag_info *ag)
338 {
339 int i;
340 naddr mask, v1_mask, dst_h, ddst_h = 0;
341 struct ws_buf *wb;
342
343
344 /* Skip this route if doing a flash update and it and the routes
345 * it aggregates have not changed recently.
346 */
347 if (ag->ag_seqno < update_seqno
348 && (ws.state & WS_ST_FLASH))
349 return;
350
351 dst_h = ag->ag_dst_h;
352 mask = ag->ag_mask;
353 v1_mask = ripv1_mask_host(htonl(dst_h),
354 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0);
355 i = 0;
356
357 /* If we are sending RIPv2 packets that cannot (or must not) be
358 * heard by RIPv1 listeners, do not worry about sub- or supernets.
359 * Subnets (from other networks) can only be sent via multicast.
360 * A pair of subnet routes might have been promoted so that they
361 * are legal to send by RIPv1.
362 * If RIPv1 is off, use the multicast buffer.
363 */
364 if ((ws.state & WS_ST_RIP2_ALL)
365 || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) {
366 /* use the RIPv2-only buffer */
367 wb = &v2buf;
368
369 } else {
370 /* use the RIPv1-or-RIPv2 buffer */
371 wb = &v12buf;
372
373 /* Convert supernet route into corresponding set of network
374 * routes for RIPv1, but leave non-contiguous netmasks
375 * to ag_check().
376 */
377 if (v1_mask > mask
378 && mask + (mask & -mask) == 0) {
379 ddst_h = v1_mask & -v1_mask;
380 i = (v1_mask & ~mask)/ddst_h;
381
382 if (i > ws.gen_limit) {
383 /* Punt if we would have to generate an
384 * unreasonable number of routes.
385 */
386 if (TRACECONTENTS)
387 trace_misc("sending %s-->%s as 1"
388 " instead of %d routes",
389 addrname(htonl(dst_h), mask,
390 1),
391 naddr_ntoa(ws.to.sin_addr
392 .s_addr),
393 i+1);
394 i = 0;
395
396 } else {
397 mask = v1_mask;
398 ws.gen_limit -= i;
399 }
400 }
401 }
402
403 do {
404 wb->n->n_family = RIP_AF_INET;
405 wb->n->n_dst = htonl(dst_h);
406 /* If the route is from router-discovery or we are
407 * shutting down, admit only a bad metric.
408 */
409 wb->n->n_metric = ((stopint || ag->ag_metric < 1)
410 ? HOPCNT_INFINITY
411 : ag->ag_metric);
412 wb->n->n_metric = htonl(wb->n->n_metric);
413 /* Any non-zero bits in the supposedly unused RIPv1 fields
414 * cause the old `routed` to ignore the route.
415 * That means the mask and so forth cannot be sent
416 * in the hybrid RIPv1/RIPv2 mode.
417 */
418 if (ws.state & WS_ST_RIP2_ALL) {
419 if (ag->ag_nhop != 0
420 && ((ws.state & WS_ST_QUERY)
421 || (ag->ag_nhop != ws.ifp->int_addr
422 && on_net(ag->ag_nhop,
423 ws.ifp->int_net,
424 ws.ifp->int_mask))))
425 wb->n->n_nhop = ag->ag_nhop;
426 wb->n->n_mask = htonl(mask);
427 wb->n->n_tag = ag->ag_tag;
428 }
429 dst_h += ddst_h;
430
431 if (++wb->n >= wb->lim)
432 supply_write(wb);
433 } while (i-- != 0);
434 }
435
436
437 /* supply one route from the table
438 */
439 /* ARGSUSED */
440 static int
walk_supply(struct radix_node * rn,struct walkarg * argp UNUSED)441 walk_supply(struct radix_node *rn,
442 struct walkarg *argp UNUSED)
443 {
444 #define RT ((struct rt_entry *)rn)
445 u_short ags;
446 char metric, pref;
447 naddr dst, nhop;
448 struct rt_spare *rts;
449 int i;
450
451
452 /* Do not advertise external remote interfaces or passive interfaces.
453 */
454 if ((RT->rt_state & RS_IF)
455 && RT->rt_ifp != 0
456 && (RT->rt_ifp->int_state & IS_PASSIVE)
457 && !(RT->rt_state & RS_MHOME))
458 return 0;
459
460 /* If being quiet about our ability to forward, then
461 * do not say anything unless responding to a query,
462 * except about our main interface.
463 */
464 if (!supplier && !(ws.state & WS_ST_QUERY)
465 && !(RT->rt_state & RS_MHOME))
466 return 0;
467
468 dst = RT->rt_dst;
469
470 /* do not collide with the fake default route */
471 if (dst == RIP_DEFAULT
472 && (ws.state & WS_ST_DEFAULT))
473 return 0;
474
475 if (RT->rt_state & RS_NET_SYN) {
476 if (RT->rt_state & RS_NET_INT) {
477 /* Do not send manual synthetic network routes
478 * into the subnet.
479 */
480 if (on_net(ws.to.sin_addr.s_addr,
481 ntohl(dst), RT->rt_mask))
482 return 0;
483
484 } else {
485 /* Do not send automatic synthetic network routes
486 * if they are not needed because no RIPv1 listeners
487 * can hear them.
488 */
489 if (ws.state & WS_ST_RIP2_ALL)
490 return 0;
491
492 /* Do not send automatic synthetic network routes to
493 * the real subnet.
494 */
495 if (on_net(ws.to.sin_addr.s_addr,
496 ntohl(dst), RT->rt_mask))
497 return 0;
498 }
499 nhop = 0;
500
501 } else {
502 /* Advertise the next hop if this is not a route for one
503 * of our interfaces and the next hop is on the same
504 * network as the target.
505 * The final determination is made by supply_out().
506 */
507 if (!(RT->rt_state & RS_IF)
508 && RT->rt_gate != myaddr
509 && RT->rt_gate != loopaddr)
510 nhop = RT->rt_gate;
511 else
512 nhop = 0;
513 }
514
515 metric = RT->rt_metric;
516 ags = 0;
517
518 if (RT->rt_state & RS_MHOME) {
519 /* retain host route of multi-homed servers */
520 ;
521
522 } else if (RT_ISHOST(RT)) {
523 /* We should always suppress (into existing network routes)
524 * the host routes for the local end of our point-to-point
525 * links.
526 * If we are suppressing host routes in general, then do so.
527 * Avoid advertising host routes onto their own network,
528 * where they should be handled by proxy-ARP.
529 */
530 if ((RT->rt_state & RS_LOCAL)
531 || ridhosts
532 || on_net(dst, ws.to_net, ws.to_mask))
533 ags |= AGS_SUPPRESS;
534
535 /* Aggregate stray host routes into network routes if allowed.
536 * We cannot aggregate host routes into small network routes
537 * without confusing RIPv1 listeners into thinking the
538 * network routes are host routes.
539 */
540 if ((ws.state & WS_ST_AG) && (ws.state & WS_ST_RIP2_ALL))
541 ags |= AGS_AGGREGATE;
542
543 } else {
544 /* Always suppress network routes into other, existing
545 * network routes
546 */
547 ags |= AGS_SUPPRESS;
548
549 /* Generate supernets if allowed.
550 * If we can be heard by RIPv1 systems, we will
551 * later convert back to ordinary nets.
552 * This unifies dealing with received supernets.
553 */
554 if ((ws.state & WS_ST_AG)
555 && ((RT->rt_state & RS_SUBNET)
556 || (ws.state & WS_ST_SUPER_AG)))
557 ags |= AGS_AGGREGATE;
558 }
559
560 /* Do not send RIPv1 advertisements of subnets to other
561 * networks. If possible, multicast them by RIPv2.
562 */
563 if ((RT->rt_state & RS_SUBNET)
564 && !(ws.state & WS_ST_RIP2_ALL)
565 && !on_net(dst, ws.to_std_net, ws.to_std_mask))
566 ags |= AGS_RIPV2 | AGS_AGGREGATE;
567
568
569 /* Do not send a route back to where it came from, except in
570 * response to a query. This is "split-horizon". That means not
571 * advertising back to the same network and so via the same interface.
572 *
573 * We want to suppress routes that might have been fragmented
574 * from this route by a RIPv1 router and sent back to us, and so we
575 * cannot forget this route here. Let the split-horizon route
576 * suppress the fragmented routes and then itself be forgotten.
577 *
578 * Include the routes for both ends of point-to-point interfaces
579 * among those suppressed by split-horizon, since the other side
580 * should knows them as well as we do.
581 *
582 * Notice spare routes with the same metric that we are about to
583 * advertise, to split the horizon on redundant, inactive paths.
584 *
585 * Do not suppress advertisements of interface-related addresses on
586 * non-point-to-point interfaces. This ensures that we have something
587 * to say every 30 seconds to help detect broken Ethernets or
588 * other interfaces where one packet every 30 seconds costs nothing.
589 */
590 if (ws.ifp != 0
591 && !(ws.state & WS_ST_QUERY)
592 && (ws.state & WS_ST_TO_ON_NET)
593 && (!(RT->rt_state & RS_IF)
594 || ws.ifp->int_if_flags & IFF_POINTOPOINT)) {
595 for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) {
596 if (rts->rts_metric > metric
597 || rts->rts_ifp != ws.ifp)
598 continue;
599
600 /* If we do not mark the route with AGS_SPLIT_HZ here,
601 * it will be poisoned-reverse, or advertised back
602 * toward its source with an infinite metric.
603 * If we have recently advertised the route with a
604 * better metric than we now have, then we should
605 * poison-reverse the route before suppressing it for
606 * split-horizon.
607 *
608 * In almost all cases, if there is no spare for the
609 * route then it is either old and dead or a brand
610 * new route. If it is brand new, there is no need
611 * for poison-reverse. If it is old and dead, it
612 * is already poisoned.
613 */
614 if (RT->rt_poison_time < now_expire
615 || RT->rt_poison_metric >= metric
616 || RT->rt_spares[1].rts_gate == 0) {
617 ags |= AGS_SPLIT_HZ;
618 ags &= ~AGS_SUPPRESS;
619 }
620 metric = HOPCNT_INFINITY;
621 break;
622 }
623 }
624
625 /* Keep track of the best metric with which the
626 * route has been advertised recently.
627 */
628 if (RT->rt_poison_metric >= metric
629 || RT->rt_poison_time < now_expire) {
630 RT->rt_poison_time = now.tv_sec;
631 RT->rt_poison_metric = metric;
632 }
633
634 /* Adjust the outgoing metric by the cost of the link.
635 * Avoid aggregation when a route is counting to infinity.
636 */
637 pref = RT->rt_poison_metric + ws.metric;
638 metric += ws.metric;
639
640 /* Do not advertise stable routes that will be ignored,
641 * unless we are answering a query.
642 * If the route recently was advertised with a metric that
643 * would have been less than infinity through this interface,
644 * we need to continue to advertise it in order to poison it.
645 */
646 if (metric >= HOPCNT_INFINITY) {
647 if (!(ws.state & WS_ST_QUERY)
648 && (pref >= HOPCNT_INFINITY
649 || RT->rt_poison_time < now_garbage))
650 return 0;
651
652 metric = HOPCNT_INFINITY;
653 }
654
655 ag_check(dst, RT->rt_mask, 0, nhop, metric, pref,
656 RT->rt_seqno, RT->rt_tag, ags, supply_out);
657 return 0;
658 #undef RT
659 }
660
661
662 /* Supply dst with the contents of the routing tables.
663 * If this won't fit in one packet, chop it up into several.
664 */
665 void
supply(struct sockaddr_in * dst,struct interface * ifp,enum output_type type,int flash,int vers,int passwd_ok)666 supply(struct sockaddr_in *dst,
667 struct interface *ifp, /* output interface */
668 enum output_type type,
669 int flash, /* 1=flash update */
670 int vers, /* RIP version */
671 int passwd_ok) /* OK to include cleartext password */
672 {
673 struct rt_entry *rt;
674 int def_metric;
675
676 ws.state = 0;
677 ws.gen_limit = 1024;
678
679 ws.to = *dst;
680 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr);
681 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask;
682
683 if (ifp != 0) {
684 ws.to_mask = ifp->int_mask;
685 ws.to_net = ifp->int_net;
686 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask))
687 ws.state |= WS_ST_TO_ON_NET;
688
689 } else {
690 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0);
691 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask;
692 rt = rtfind(dst->sin_addr.s_addr);
693 if (rt)
694 ifp = rt->rt_ifp;
695 }
696
697 ws.npackets = 0;
698 if (flash)
699 ws.state |= WS_ST_FLASH;
700
701 if ((ws.ifp = ifp) == 0) {
702 ws.metric = 1;
703 } else {
704 /* Adjust the advertised metric by the outgoing interface
705 * metric.
706 */
707 ws.metric = ifp->int_metric + 1 + ifp->int_adj_outmetric;
708 }
709
710 ripv12_buf.rip.rip_vers = vers;
711
712 switch (type) {
713 case OUT_MULTICAST:
714 if (ifp->int_if_flags & IFF_MULTICAST)
715 v2buf.type = OUT_MULTICAST;
716 else
717 v2buf.type = NO_OUT_MULTICAST;
718 v12buf.type = OUT_BROADCAST;
719 break;
720
721 case OUT_QUERY:
722 ws.state |= WS_ST_QUERY;
723 /* FALLTHROUGH */
724 case OUT_BROADCAST:
725 case OUT_UNICAST:
726 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2;
727 v12buf.type = type;
728 break;
729
730 case NO_OUT_MULTICAST:
731 case NO_OUT_RIPV2:
732 break; /* no output */
733 }
734
735 if (vers == RIPv2) {
736 /* full RIPv2 only if cannot be heard by RIPv1 listeners */
737 if (type != OUT_BROADCAST)
738 ws.state |= WS_ST_RIP2_ALL;
739 if ((ws.state & WS_ST_QUERY)
740 || !(ws.state & WS_ST_TO_ON_NET)) {
741 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG);
742 } else if (ifp == 0 || !(ifp->int_state & IS_NO_AG)) {
743 ws.state |= WS_ST_AG;
744 if (type != OUT_BROADCAST
745 && (ifp == 0
746 || !(ifp->int_state & IS_NO_SUPER_AG)))
747 ws.state |= WS_ST_SUPER_AG;
748 }
749 }
750
751 ws.a = (vers == RIPv2) ? find_auth(ifp) : 0;
752 if (!passwd_ok && ws.a != 0 && ws.a->type == RIP_AUTH_PW)
753 ws.a = 0;
754 clr_ws_buf(&v12buf,ws.a);
755 clr_ws_buf(&v2buf,ws.a);
756
757 /* Fake a default route if asked and if there is not already
758 * a better, real default route.
759 */
760 if (supplier && (def_metric = ifp->int_d_metric) != 0) {
761 if (0 == (rt = rtget(RIP_DEFAULT, 0))
762 || rt->rt_metric+ws.metric >= def_metric) {
763 ws.state |= WS_ST_DEFAULT;
764 ag_check(0, 0, 0, 0, def_metric, def_metric,
765 0, 0, 0, supply_out);
766 } else {
767 def_metric = rt->rt_metric+ws.metric;
768 }
769
770 /* If both RIPv2 and the poor-man's router discovery
771 * kludge are on, arrange to advertise an extra
772 * default route via RIPv1.
773 */
774 if ((ws.state & WS_ST_RIP2_ALL)
775 && (ifp->int_state & IS_PM_RDISC)) {
776 ripv12_buf.rip.rip_vers = RIPv1;
777 v12buf.n->n_family = RIP_AF_INET;
778 v12buf.n->n_dst = htonl(RIP_DEFAULT);
779 v12buf.n->n_metric = htonl(def_metric);
780 v12buf.n++;
781 }
782 }
783
784 (void)rn_walktree(rhead, walk_supply, 0);
785 ag_flush(0,0,supply_out);
786
787 /* Flush the packet buffers, provided they are not empty and
788 * do not contain only the password.
789 */
790 if (v12buf.n != v12buf.base
791 && (v12buf.n > v12buf.base+1
792 || v12buf.base->n_family != RIP_AF_AUTH))
793 supply_write(&v12buf);
794 if (v2buf.n != v2buf.base
795 && (v2buf.n > v2buf.base+1
796 || v2buf.base->n_family != RIP_AF_AUTH))
797 supply_write(&v2buf);
798
799 /* If we sent nothing and this is an answer to a query, send
800 * an empty buffer.
801 */
802 if (ws.npackets == 0
803 && (ws.state & WS_ST_QUERY))
804 supply_write(&v12buf);
805 }
806
807
808 /* send all of the routing table or just do a flash update
809 */
810 void
rip_bcast(int flash)811 rip_bcast(int flash)
812 {
813 #ifdef _HAVE_SIN_LEN
814 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
815 #else
816 static struct sockaddr_in dst = {AF_INET};
817 #endif
818 struct interface *ifp;
819 enum output_type type;
820 int vers;
821 struct timeval rtime;
822
823
824 need_flash = 0;
825 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME);
826 no_flash = rtime;
827 timevaladd(&no_flash, &now);
828
829 if (rip_sock < 0)
830 return;
831
832 trace_act("send %s and inhibit dynamic updates for %.3f sec",
833 flash ? "dynamic update" : "all routes",
834 rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0);
835
836 LIST_FOREACH(ifp, &ifnet, int_list) {
837 /* Skip interfaces not doing RIP.
838 * Do try broken interfaces to see if they have healed.
839 */
840 if (IS_RIP_OUT_OFF(ifp->int_state))
841 continue;
842
843 /* skip turned off interfaces */
844 if (!iff_up(ifp->int_if_flags))
845 continue;
846
847 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1;
848
849 if (ifp->int_if_flags & IFF_BROADCAST) {
850 /* ordinary, hardware interface */
851 dst.sin_addr.s_addr = ifp->int_brdaddr;
852
853 if (vers == RIPv2
854 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
855 type = OUT_MULTICAST;
856 } else {
857 type = OUT_BROADCAST;
858 }
859
860 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
861 /* point-to-point hardware interface */
862 dst.sin_addr.s_addr = ifp->int_dstaddr;
863 if (vers == RIPv2 &&
864 ifp->int_if_flags & IFF_MULTICAST &&
865 !(ifp->int_state & IS_NO_RIP_MCAST)) {
866 type = OUT_MULTICAST;
867 } else {
868 type = OUT_UNICAST;
869 }
870
871 } else if (ifp->int_state & IS_REMOTE) {
872 /* remote interface */
873 dst.sin_addr.s_addr = ifp->int_addr;
874 type = OUT_UNICAST;
875
876 } else {
877 /* ATM, HIPPI, etc. */
878 continue;
879 }
880
881 supply(&dst, ifp, type, flash, vers, 1);
882 }
883
884 update_seqno++; /* all routes are up to date */
885 }
886
887
888 /* Ask for routes
889 * Do it only once to an interface, and not even after the interface
890 * was broken and recovered.
891 */
892 void
rip_query(void)893 rip_query(void)
894 {
895 #ifdef _HAVE_SIN_LEN
896 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
897 #else
898 static struct sockaddr_in dst = {AF_INET};
899 #endif
900 struct interface *ifp;
901 struct rip buf;
902 enum output_type type;
903
904
905 if (rip_sock < 0)
906 return;
907
908 memset(&buf, 0, sizeof(buf));
909
910 LIST_FOREACH(ifp, &ifnet, int_list) {
911 /* Skip interfaces those already queried.
912 * Do not ask via interfaces through which we don't
913 * accept input. Do not ask via interfaces that cannot
914 * send RIP packets.
915 * Do try broken interfaces to see if they have healed.
916 */
917 if (IS_RIP_IN_OFF(ifp->int_state)
918 || ifp->int_query_time != NEVER)
919 continue;
920
921 /* skip turned off interfaces */
922 if (!iff_up(ifp->int_if_flags))
923 continue;
924
925 buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1;
926 buf.rip_cmd = RIPCMD_REQUEST;
927 buf.rip_nets[0].n_family = RIP_AF_UNSPEC;
928 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY);
929
930 /* Send a RIPv1 query only if allowed and if we will
931 * listen to RIPv1 routers.
932 */
933 if ((ifp->int_state & IS_NO_RIPV1_OUT)
934 || (ifp->int_state & IS_NO_RIPV1_IN)) {
935 buf.rip_vers = RIPv2;
936 } else {
937 buf.rip_vers = RIPv1;
938 }
939
940 if (ifp->int_if_flags & IFF_BROADCAST) {
941 /* ordinary, hardware interface */
942 dst.sin_addr.s_addr = ifp->int_brdaddr;
943
944 /* Broadcast RIPv1 queries and RIPv2 queries
945 * when the hardware cannot multicast.
946 */
947 if (buf.rip_vers == RIPv2
948 && (ifp->int_if_flags & IFF_MULTICAST)
949 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
950 type = OUT_MULTICAST;
951 } else {
952 type = OUT_BROADCAST;
953 }
954
955 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
956 /* point-to-point hardware interface */
957 dst.sin_addr.s_addr = ifp->int_dstaddr;
958 type = OUT_UNICAST;
959
960 } else if (ifp->int_state & IS_REMOTE) {
961 /* remote interface */
962 dst.sin_addr.s_addr = ifp->int_addr;
963 type = OUT_UNICAST;
964
965 } else {
966 /* ATM, HIPPI, etc. */
967 continue;
968 }
969
970 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL;
971 if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0)
972 if_sick(ifp);
973 }
974 }
975