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 * 3. 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 * @(#)output.c 8.1 (Berkeley) 6/5/93
30 * $FreeBSD: src/sbin/routed/output.c,v 1.5.2.1 2000/08/14 17:00:03 sheldonh Exp $
31 */
32
33 #include "defs.h"
34
35 u_int update_seqno;
36
37
38 /* walk the tree of routes with this for output
39 */
40 struct {
41 struct sockaddr_in to;
42 naddr to_mask;
43 naddr to_net;
44 naddr to_std_mask;
45 naddr to_std_net;
46 struct interface *ifp; /* usually output interface */
47 struct auth *a;
48 char metric; /* adjust metrics by interface */
49 int npackets;
50 int gen_limit;
51 u_int state;
52 #define WS_ST_FLASH 0x001 /* send only changed routes */
53 #define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */
54 #define WS_ST_AG 0x004 /* ok to aggregate subnets */
55 #define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */
56 #define WS_ST_QUERY 0x010 /* responding to a query */
57 #define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */
58 #define WS_ST_DEFAULT 0x040 /* faking a default */
59 } ws;
60
61 /* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */
62 struct ws_buf v12buf;
63 union pkt_buf ripv12_buf;
64
65 /* Another for only RIPv2 listeners */
66 struct ws_buf v2buf;
67 union pkt_buf rip_v2_buf;
68
69
70
71 void
bufinit(void)72 bufinit(void)
73 {
74 ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE;
75 v12buf.buf = &ripv12_buf.rip;
76 v12buf.base = &v12buf.buf->rip_nets[0];
77
78 rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE;
79 rip_v2_buf.rip.rip_vers = RIPv2;
80 v2buf.buf = &rip_v2_buf.rip;
81 v2buf.base = &v2buf.buf->rip_nets[0];
82 }
83
84
85 /* Send the contents of the global buffer via the non-multicast socket
86 */
87 int /* <0 on failure */
output(enum output_type type,struct sockaddr_in * dst,struct interface * ifp,struct rip * buf,int size)88 output(enum output_type type,
89 struct sockaddr_in *dst, /* send to here */
90 struct interface *ifp,
91 struct rip *buf,
92 int size) /* this many bytes */
93 {
94 struct sockaddr_in in;
95 int flags;
96 const char *msg;
97 int res;
98 naddr tgt_mcast;
99 int soc;
100 int serrno;
101
102 in = *dst;
103 if (in.sin_port == 0)
104 in.sin_port = htons(RIP_PORT);
105 if (in.sin_len == 0)
106 in.sin_len = sizeof(in);
107
108 soc = rip_sock;
109 flags = 0;
110
111 switch (type) {
112 case OUT_QUERY:
113 msg = "Answer Query";
114 if (soc < 0)
115 soc = ifp->int_rip_sock;
116 break;
117 case OUT_UNICAST:
118 msg = "Send";
119 if (soc < 0)
120 soc = ifp->int_rip_sock;
121 flags = MSG_DONTROUTE;
122 break;
123 case OUT_BROADCAST:
124 if (ifp->int_if_flags & IFF_POINTOPOINT) {
125 msg = "Send";
126 } else {
127 msg = "Send bcast";
128 }
129 flags = MSG_DONTROUTE;
130 break;
131 case OUT_MULTICAST:
132 if (ifp->int_if_flags & IFF_POINTOPOINT) {
133 msg = "Send pt-to-pt";
134 } else if (ifp->int_state & IS_DUP) {
135 trace_act("abort multicast output via %s"
136 " with duplicate address",
137 ifp->int_name);
138 return 0;
139 } else {
140 msg = "Send mcast";
141 if (rip_sock_mcast != ifp) {
142 #ifdef MCAST_PPP_BUG
143 /* Do not specify the primary interface
144 * explicitly if we have the multicast
145 * point-to-point kernel bug, since the
146 * kernel will do the wrong thing if the
147 * local address of a point-to-point link
148 * is the same as the address of an ordinary
149 * interface.
150 */
151 if (ifp->int_addr == myaddr) {
152 tgt_mcast = 0;
153 } else
154 #endif
155 tgt_mcast = ifp->int_addr;
156 if (0 > setsockopt(rip_sock,
157 IPPROTO_IP, IP_MULTICAST_IF,
158 &tgt_mcast,
159 sizeof(tgt_mcast))) {
160 serrno = errno;
161 LOGERR("setsockopt(rip_sock,"
162 "IP_MULTICAST_IF)");
163 errno = serrno;
164 ifp = NULL;
165 return -1;
166 }
167 rip_sock_mcast = ifp;
168 }
169 in.sin_addr.s_addr = htonl(INADDR_RIP_GROUP);
170 }
171 break;
172
173 case NO_OUT_MULTICAST:
174 case NO_OUT_RIPV2:
175 default:
176 #ifdef DEBUG
177 abort();
178 #endif
179 return -1;
180 }
181
182 trace_rip(msg, "to", &in, ifp, buf, size);
183
184 res = sendto(soc, buf, size, flags,
185 (struct sockaddr *)&in, sizeof(in));
186 if (res < 0
187 && (ifp == NULL || !(ifp->int_state & IS_BROKE))) {
188 serrno = errno;
189 msglog("%s sendto(%s%s%s.%d): %s", msg,
190 ifp != NULL ? ifp->int_name : "",
191 ifp != NULL ? ", " : "",
192 inet_ntoa(in.sin_addr),
193 ntohs(in.sin_port),
194 strerror(errno));
195 errno = serrno;
196 }
197
198 return res;
199 }
200
201
202 /* Find the first key for a packet to send.
203 * Try for a key that is eligible and has not expired, but settle for
204 * the last key if they have all expired.
205 * If no key is ready yet, give up.
206 */
207 struct auth *
find_auth(struct interface * ifp)208 find_auth(struct interface *ifp)
209 {
210 struct auth *ap, *res;
211 int i;
212
213
214 if (ifp == NULL)
215 return 0;
216
217 res = NULL;
218 ap = ifp->int_auth;
219 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) {
220 /* stop looking after the last key */
221 if (ap->type == RIP_AUTH_NONE)
222 break;
223
224 /* ignore keys that are not ready yet */
225 if ((u_long)ap->start > (u_long)clk.tv_sec)
226 continue;
227
228 if ((u_long)ap->end < (u_long)clk.tv_sec) {
229 /* note best expired password as a fall-back */
230 if (res == NULL || (u_long)ap->end > (u_long)res->end)
231 res = ap;
232 continue;
233 }
234
235 /* note key with the best future */
236 if (res == NULL || (u_long)res->end < (u_long)ap->end)
237 res = ap;
238 }
239 return res;
240 }
241
242
243 void
clr_ws_buf(struct ws_buf * wb,struct auth * ap)244 clr_ws_buf(struct ws_buf *wb,
245 struct auth *ap)
246 {
247 struct netauth *na;
248
249 wb->lim = wb->base + NETS_LEN;
250 wb->n = wb->base;
251 memset(wb->n, 0, NETS_LEN*sizeof(*wb->n));
252
253 /* (start to) install authentication if appropriate
254 */
255 if (ap == NULL)
256 return;
257
258 na = (struct netauth*)wb->n;
259 if (ap->type == RIP_AUTH_PW) {
260 na->a_family = RIP_AF_AUTH;
261 na->a_type = RIP_AUTH_PW;
262 memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw));
263 wb->n++;
264
265 } else if (ap->type == RIP_AUTH_MD5) {
266 na->a_family = RIP_AF_AUTH;
267 na->a_type = RIP_AUTH_MD5;
268 na->au.a_md5.md5_keyid = ap->keyid;
269 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_LEN;
270 na->au.a_md5.md5_seqno = htonl(clk.tv_sec);
271 wb->n++;
272 wb->lim--; /* make room for trailer */
273 }
274 }
275
276
277 void
end_md5_auth(struct ws_buf * wb,struct auth * ap)278 end_md5_auth(struct ws_buf *wb,
279 struct auth *ap)
280 {
281 struct netauth *na, *na2;
282 MD5_CTX md5_ctx;
283 int len;
284
285
286 na = (struct netauth*)wb->base;
287 na2 = (struct netauth*)wb->n;
288 len = (char *)na2-(char *)wb->buf;
289 na2->a_family = RIP_AF_AUTH;
290 na2->a_type = htons(1);
291 na->au.a_md5.md5_pkt_len = htons(len);
292 MD5_Init(&md5_ctx);
293 MD5_Update(&md5_ctx, (u_char *)wb->buf, len);
294 MD5_Update(&md5_ctx, ap->key, RIP_AUTH_MD5_LEN);
295 MD5_Final(na2->au.au_pw, &md5_ctx);
296 wb->n++;
297 }
298
299
300 /* Send the buffer
301 */
302 static void
supply_write(struct ws_buf * wb)303 supply_write(struct ws_buf *wb)
304 {
305 /* Output multicast only if legal.
306 * If we would multicast and it would be illegal, then discard the
307 * packet.
308 */
309 switch (wb->type) {
310 case NO_OUT_MULTICAST:
311 trace_pkt("skip multicast to %s because impossible",
312 naddr_ntoa(ws.to.sin_addr.s_addr));
313 break;
314 case NO_OUT_RIPV2:
315 break;
316 default:
317 if (ws.a != NULL && ws.a->type == RIP_AUTH_MD5)
318 end_md5_auth(wb,ws.a);
319 if (output(wb->type, &ws.to, ws.ifp, wb->buf,
320 ((char *)wb->n - (char*)wb->buf)) < 0
321 && ws.ifp != NULL)
322 if_sick(ws.ifp);
323 ws.npackets++;
324 break;
325 }
326
327 clr_ws_buf(wb,ws.a);
328 }
329
330
331 /* put an entry into the packet
332 */
333 static void
supply_out(struct ag_info * ag)334 supply_out(struct ag_info *ag)
335 {
336 int i;
337 naddr mask, v1_mask, dst_h, ddst_h = 0;
338 struct ws_buf *wb;
339
340
341 /* Skip this route if doing a flash update and it and the routes
342 * it aggregates have not changed recently.
343 */
344 if (ag->ag_seqno < update_seqno
345 && (ws.state & WS_ST_FLASH))
346 return;
347
348 dst_h = ag->ag_dst_h;
349 mask = ag->ag_mask;
350 v1_mask = ripv1_mask_host(htonl(dst_h),
351 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0);
352 i = 0;
353
354 /* If we are sending RIPv2 packets that cannot (or must not) be
355 * heard by RIPv1 listeners, do not worry about sub- or supernets.
356 * Subnets (from other networks) can only be sent via multicast.
357 * A pair of subnet routes might have been promoted so that they
358 * are legal to send by RIPv1.
359 * If RIPv1 is off, use the multicast buffer.
360 */
361 if ((ws.state & WS_ST_RIP2_ALL)
362 || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) {
363 /* use the RIPv2-only buffer */
364 wb = &v2buf;
365
366 } else {
367 /* use the RIPv1-or-RIPv2 buffer */
368 wb = &v12buf;
369
370 /* Convert supernet route into corresponding set of network
371 * routes for RIPv1, but leave non-contiguous netmasks
372 * to ag_check().
373 */
374 if (v1_mask > mask
375 && mask + (mask & -mask) == 0) {
376 ddst_h = v1_mask & -v1_mask;
377 i = (v1_mask & ~mask)/ddst_h;
378
379 if (i > ws.gen_limit) {
380 /* Punt if we would have to generate an
381 * unreasonable number of routes.
382 */
383 if (TRACECONTENTS)
384 trace_misc("sending %s-->%s as 1"
385 " instead of %d routes",
386 addrname(htonl(dst_h), mask,
387 1),
388 naddr_ntoa(ws.to.sin_addr
389 .s_addr),
390 i+1);
391 i = 0;
392
393 } else {
394 mask = v1_mask;
395 ws.gen_limit -= i;
396 }
397 }
398 }
399
400 do {
401 wb->n->n_family = RIP_AF_INET;
402 wb->n->n_dst = htonl(dst_h);
403 /* If the route is from router-discovery or we are
404 * shutting down, admit only a bad metric.
405 */
406 wb->n->n_metric = ((stopint || ag->ag_metric < 1)
407 ? HOPCNT_INFINITY
408 : ag->ag_metric);
409 wb->n->n_metric = htonl(wb->n->n_metric);
410 /* Any non-zero bits in the supposedly unused RIPv1 fields
411 * cause the old `routed` to ignore the route.
412 * That means the mask and so forth cannot be sent
413 * in the hybrid RIPv1/RIPv2 mode.
414 */
415 if (ws.state & WS_ST_RIP2_ALL) {
416 if (ag->ag_nhop != 0
417 && ((ws.state & WS_ST_QUERY)
418 || (ag->ag_nhop != ws.ifp->int_addr
419 && on_net(ag->ag_nhop,
420 ws.ifp->int_net,
421 ws.ifp->int_mask))))
422 wb->n->n_nhop = ag->ag_nhop;
423 wb->n->n_mask = htonl(mask);
424 wb->n->n_tag = ag->ag_tag;
425 }
426 dst_h += ddst_h;
427
428 if (++wb->n >= wb->lim)
429 supply_write(wb);
430 } while (i-- != 0);
431 }
432
433
434 /* supply one route from the table
435 */
436 static int
walk_supply(struct radix_node * rn,void * argp __unused)437 walk_supply(struct radix_node *rn, void *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)
536 && !(ws.state & WS_ST_RIP2_ALL))
537 ags |= AGS_AGGREGATE;
538
539 } else {
540 /* Always suppress network routes into other, existing
541 * network routes
542 */
543 ags |= AGS_SUPPRESS;
544
545 /* Generate supernets if allowed.
546 * If we can be heard by RIPv1 systems, we will
547 * later convert back to ordinary nets.
548 * This unifies dealing with received supernets.
549 */
550 if ((ws.state & WS_ST_AG)
551 && ((RT->rt_state & RS_SUBNET)
552 || (ws.state & WS_ST_SUPER_AG)))
553 ags |= AGS_AGGREGATE;
554 }
555
556 /* Do not send RIPv1 advertisements of subnets to other
557 * networks. If possible, multicast them by RIPv2.
558 */
559 if ((RT->rt_state & RS_SUBNET)
560 && !(ws.state & WS_ST_RIP2_ALL)
561 && !on_net(dst, ws.to_std_net, ws.to_std_mask))
562 ags |= AGS_RIPV2 | AGS_AGGREGATE;
563
564
565 /* Do not send a route back to where it came from, except in
566 * response to a query. This is "split-horizon". That means not
567 * advertising back to the same network and so via the same interface.
568 *
569 * We want to suppress routes that might have been fragmented
570 * from this route by a RIPv1 router and sent back to us, and so we
571 * cannot forget this route here. Let the split-horizon route
572 * suppress the fragmented routes and then itself be forgotten.
573 *
574 * Include the routes for both ends of point-to-point interfaces
575 * among those suppressed by split-horizon, since the other side
576 * should knows them as well as we do.
577 *
578 * Notice spare routes with the same metric that we are about to
579 * advertise, to split the horizon on redundant, inactive paths.
580 */
581 if (ws.ifp != NULL
582 && !(ws.state & WS_ST_QUERY)
583 && (ws.state & WS_ST_TO_ON_NET)
584 && (!(RT->rt_state & RS_IF)
585 || ws.ifp->int_if_flags & IFF_POINTOPOINT)) {
586 for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) {
587 if (rts->rts_metric > metric
588 || rts->rts_ifp != ws.ifp)
589 continue;
590
591 /* If we do not mark the route with AGS_SPLIT_HZ here,
592 * it will be poisoned-reverse, or advertised back
593 * toward its source with an infinite metric.
594 * If we have recently advertised the route with a
595 * better metric than we now have, then we should
596 * poison-reverse the route before suppressing it for
597 * split-horizon.
598 *
599 * In almost all cases, if there is no spare for the
600 * route then it is either old and dead or a brand
601 * new route. If it is brand new, there is no need
602 * for poison-reverse. If it is old and dead, it
603 * is already poisoned.
604 */
605 if (RT->rt_poison_time < now_expire
606 || RT->rt_poison_metric >= metric
607 || RT->rt_spares[1].rts_gate == 0) {
608 ags |= AGS_SPLIT_HZ;
609 ags &= ~AGS_SUPPRESS;
610 }
611 metric = HOPCNT_INFINITY;
612 break;
613 }
614 }
615
616 /* Keep track of the best metric with which the
617 * route has been advertised recently.
618 */
619 if (RT->rt_poison_metric >= metric
620 || RT->rt_poison_time < now_expire) {
621 RT->rt_poison_time = now.tv_sec;
622 RT->rt_poison_metric = metric;
623 }
624
625 /* Adjust the outgoing metric by the cost of the link.
626 * Avoid aggregation when a route is counting to infinity.
627 */
628 pref = RT->rt_poison_metric + ws.metric;
629 metric += ws.metric;
630
631 /* Do not advertise stable routes that will be ignored,
632 * unless we are answering a query.
633 * If the route recently was advertised with a metric that
634 * would have been less than infinity through this interface,
635 * we need to continue to advertise it in order to poison it.
636 */
637 if (metric >= HOPCNT_INFINITY) {
638 if (!(ws.state & WS_ST_QUERY)
639 && (pref >= HOPCNT_INFINITY
640 || RT->rt_poison_time < now_garbage))
641 return 0;
642
643 metric = HOPCNT_INFINITY;
644 }
645
646 ag_check(dst, RT->rt_mask, 0, nhop, metric, pref,
647 RT->rt_seqno, RT->rt_tag, ags, supply_out);
648 return 0;
649 #undef RT
650 }
651
652
653 /* Supply dst with the contents of the routing tables.
654 * If this won't fit in one packet, chop it up into several.
655 */
656 void
supply(struct sockaddr_in * dst,struct interface * ifp,enum output_type type,int flash,int vers,int passwd_ok)657 supply(struct sockaddr_in *dst,
658 struct interface *ifp, /* output interface */
659 enum output_type type,
660 int flash, /* 1=flash update */
661 int vers, /* RIP version */
662 int passwd_ok) /* OK to include cleartext password */
663 {
664 struct rt_entry *rt;
665 int def_metric;
666
667
668 ws.state = 0;
669 ws.gen_limit = 1024;
670
671 ws.to = *dst;
672 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr);
673 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask;
674
675 if (ifp != NULL) {
676 ws.to_mask = ifp->int_mask;
677 ws.to_net = ifp->int_net;
678 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask))
679 ws.state |= WS_ST_TO_ON_NET;
680
681 } else {
682 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0);
683 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask;
684 rt = rtfind(dst->sin_addr.s_addr);
685 if (rt)
686 ifp = rt->rt_ifp;
687 }
688
689 ws.npackets = 0;
690 if (flash)
691 ws.state |= WS_ST_FLASH;
692
693 if ((ws.ifp = ifp) == NULL) {
694 ws.metric = 1;
695 } else {
696 /* Adjust the advertised metric by the outgoing interface
697 * metric.
698 */
699 ws.metric = ifp->int_metric+1;
700 }
701
702 ripv12_buf.rip.rip_vers = vers;
703
704 switch (type) {
705 case OUT_MULTICAST:
706 if (ifp->int_if_flags & IFF_MULTICAST)
707 v2buf.type = OUT_MULTICAST;
708 else
709 v2buf.type = NO_OUT_MULTICAST;
710 v12buf.type = OUT_BROADCAST;
711 break;
712
713 case OUT_QUERY:
714 ws.state |= WS_ST_QUERY;
715 /* fall through */
716 case OUT_BROADCAST:
717 case OUT_UNICAST:
718 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2;
719 v12buf.type = type;
720 break;
721
722 case NO_OUT_MULTICAST:
723 case NO_OUT_RIPV2:
724 break; /* no output */
725 }
726
727 if (vers == RIPv2) {
728 /* full RIPv2 only if cannot be heard by RIPv1 listeners */
729 if (type != OUT_BROADCAST)
730 ws.state |= WS_ST_RIP2_ALL;
731 if ((ws.state & WS_ST_QUERY)
732 || !(ws.state & WS_ST_TO_ON_NET)) {
733 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG);
734 } else if (ifp == NULL || !(ifp->int_state & IS_NO_AG)) {
735 ws.state |= WS_ST_AG;
736 if (type != OUT_BROADCAST
737 && (ifp == NULL
738 || !(ifp->int_state & IS_NO_SUPER_AG)))
739 ws.state |= WS_ST_SUPER_AG;
740 }
741 }
742
743 ws.a = (vers == RIPv2) ? find_auth(ifp) : 0;
744 if (!passwd_ok && ws.a != NULL && ws.a->type == RIP_AUTH_PW)
745 ws.a = NULL;
746 clr_ws_buf(&v12buf,ws.a);
747 clr_ws_buf(&v2buf,ws.a);
748
749 /* Fake a default route if asked and if there is not already
750 * a better, real default route.
751 */
752 if (supplier && (def_metric = ifp->int_d_metric) != 0) {
753 if (NULL == (rt = rtget(RIP_DEFAULT, 0))
754 || rt->rt_metric+ws.metric >= def_metric) {
755 ws.state |= WS_ST_DEFAULT;
756 ag_check(0, 0, 0, 0, def_metric, def_metric,
757 0, 0, 0, supply_out);
758 } else {
759 def_metric = rt->rt_metric+ws.metric;
760 }
761
762 /* If both RIPv2 and the poor-man's router discovery
763 * kludge are on, arrange to advertise an extra
764 * default route via RIPv1.
765 */
766 if ((ws.state & WS_ST_RIP2_ALL)
767 && (ifp->int_state & IS_PM_RDISC)) {
768 ripv12_buf.rip.rip_vers = RIPv1;
769 v12buf.n->n_family = RIP_AF_INET;
770 v12buf.n->n_dst = htonl(RIP_DEFAULT);
771 v12buf.n->n_metric = htonl(def_metric);
772 v12buf.n++;
773 }
774 }
775
776 rhead->rnh_walktree(rhead, walk_supply, NULL);
777 ag_flush(0, 0, supply_out);
778
779 /* Flush the packet buffers, provided they are not empty and
780 * do not contain only the password.
781 */
782 if (v12buf.n != v12buf.base
783 && (v12buf.n > v12buf.base+1
784 || v12buf.base->n_family != RIP_AF_AUTH))
785 supply_write(&v12buf);
786 if (v2buf.n != v2buf.base
787 && (v2buf.n > v2buf.base+1
788 || v2buf.base->n_family != RIP_AF_AUTH))
789 supply_write(&v2buf);
790
791 /* If we sent nothing and this is an answer to a query, send
792 * an empty buffer.
793 */
794 if (ws.npackets == 0
795 && (ws.state & WS_ST_QUERY))
796 supply_write(&v12buf);
797 }
798
799
800 /* send all of the routing table or just do a flash update
801 */
802 void
rip_bcast(int flash)803 rip_bcast(int flash)
804 {
805 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
806 struct interface *ifp;
807 enum output_type type;
808 int vers;
809 struct timeval rtime;
810
811
812 need_flash = 0;
813 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME);
814 no_flash = rtime;
815 timevaladd(&no_flash, &now);
816
817 if (rip_sock < 0)
818 return;
819
820 trace_act("send %s and inhibit dynamic updates for %.3f sec",
821 flash ? "dynamic update" : "all routes",
822 rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0);
823
824 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
825 /* Skip interfaces not doing RIP.
826 * Do try broken interfaces to see if they have healed.
827 */
828 if (IS_RIP_OUT_OFF(ifp->int_state))
829 continue;
830
831 /* skip turned off interfaces */
832 if (!iff_up(ifp->int_if_flags))
833 continue;
834
835 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1;
836
837 if (ifp->int_if_flags & IFF_BROADCAST) {
838 /* ordinary, hardware interface */
839 dst.sin_addr.s_addr = ifp->int_brdaddr;
840
841 if (vers == RIPv2
842 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
843 type = OUT_MULTICAST;
844 } else {
845 type = OUT_BROADCAST;
846 }
847
848 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
849 /* point-to-point hardware interface */
850 dst.sin_addr.s_addr = ifp->int_dstaddr;
851 type = OUT_UNICAST;
852
853 } else if (ifp->int_state & IS_REMOTE) {
854 /* remote interface */
855 dst.sin_addr.s_addr = ifp->int_addr;
856 type = OUT_UNICAST;
857
858 } else {
859 /* ATM, HIPPI, etc. */
860 continue;
861 }
862
863 supply(&dst, ifp, type, flash, vers, 1);
864 }
865
866 update_seqno++; /* all routes are up to date */
867 }
868
869
870 /* Ask for routes
871 * Do it only once to an interface, and not even after the interface
872 * was broken and recovered.
873 */
874 void
rip_query(void)875 rip_query(void)
876 {
877 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}};
878 struct interface *ifp;
879 struct rip buf;
880 enum output_type type;
881
882
883 if (rip_sock < 0)
884 return;
885
886 memset(&buf, 0, sizeof(buf));
887
888 for (ifp = ifnet; ifp; ifp = ifp->int_next) {
889 /* Skip interfaces those already queried.
890 * Do not ask via interfaces through which we don't
891 * accept input. Do not ask via interfaces that cannot
892 * send RIP packets.
893 * Do try broken interfaces to see if they have healed.
894 */
895 if (IS_RIP_IN_OFF(ifp->int_state)
896 || ifp->int_query_time != NEVER)
897 continue;
898
899 /* skip turned off interfaces */
900 if (!iff_up(ifp->int_if_flags))
901 continue;
902
903 buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1;
904 buf.rip_cmd = RIPCMD_REQUEST;
905 buf.rip_nets[0].n_family = RIP_AF_UNSPEC;
906 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY);
907
908 /* Send a RIPv1 query only if allowed and if we will
909 * listen to RIPv1 routers.
910 */
911 if ((ifp->int_state & IS_NO_RIPV1_OUT)
912 || (ifp->int_state & IS_NO_RIPV1_IN)) {
913 buf.rip_vers = RIPv2;
914 } else {
915 buf.rip_vers = RIPv1;
916 }
917
918 if (ifp->int_if_flags & IFF_BROADCAST) {
919 /* ordinary, hardware interface */
920 dst.sin_addr.s_addr = ifp->int_brdaddr;
921
922 /* Broadcast RIPv1 queries and RIPv2 queries
923 * when the hardware cannot multicast.
924 */
925 if (buf.rip_vers == RIPv2
926 && (ifp->int_if_flags & IFF_MULTICAST)
927 && !(ifp->int_state & IS_NO_RIP_MCAST)) {
928 type = OUT_MULTICAST;
929 } else {
930 type = OUT_BROADCAST;
931 }
932
933 } else if (ifp->int_if_flags & IFF_POINTOPOINT) {
934 /* point-to-point hardware interface */
935 dst.sin_addr.s_addr = ifp->int_dstaddr;
936 type = OUT_UNICAST;
937
938 } else if (ifp->int_state & IS_REMOTE) {
939 /* remote interface */
940 dst.sin_addr.s_addr = ifp->int_addr;
941 type = OUT_UNICAST;
942
943 } else {
944 /* ATM, HIPPI, etc. */
945 continue;
946 }
947
948 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL;
949 if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0)
950 if_sick(ifp);
951 }
952 }
953