output.c revision 1.17
1 /* $NetBSD: output.c,v 1.17 1999/02/23 10:47:40 christos Exp $ */ 2 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgment: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #if !defined(lint) && !defined(sgi) && !defined(__NetBSD__) 37 static char sccsid[] __attribute__((unused)) = "@(#)output.c 8.1 (Berkeley) 6/5/93"; 38 #elif defined(__NetBSD__) 39 #include <sys/cdefs.h> 40 __RCSID("$NetBSD: output.c,v 1.17 1999/02/23 10:47:40 christos Exp $"); 41 #endif 42 43 #include "defs.h" 44 45 46 u_int update_seqno; 47 48 49 /* walk the tree of routes with this for output 50 */ 51 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 union pkt_buf ripv12_buf; 75 76 /* Another for only RIPv2 listeners */ 77 struct ws_buf v2buf; 78 union pkt_buf rip_v2_buf; 79 80 81 82 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 */ 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 sin; 106 int flags; 107 const char *msg; 108 int res; 109 naddr tgt_mcast; 110 int soc; 111 int serrno; 112 113 sin = *dst; 114 if (sin.sin_port == 0) 115 sin.sin_port = htons(RIP_PORT); 116 #ifdef _HAVE_SIN_LEN 117 if (sin.sin_len == 0) 118 sin.sin_len = sizeof(sin); 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) { 146 msg = "Send pt-to-pt"; 147 } else if (ifp->int_state & IS_DUP) { 148 trace_act("abort multicast output via %s" 149 " with duplicate address", 150 ifp->int_name); 151 return 0; 152 } else { 153 msg = "Send mcast"; 154 if (rip_sock_mcast != ifp) { 155 #ifdef MCAST_PPP_BUG 156 /* Do not specify the primary interface 157 * explicitly if we have the multicast 158 * point-to-point kernel bug, since the 159 * kernel will do the wrong thing if the 160 * local address of a point-to-point link 161 * is the same as the address of an ordinary 162 * interface. 163 */ 164 if (ifp->int_addr == myaddr) { 165 tgt_mcast = 0; 166 } else 167 #endif 168 tgt_mcast = ifp->int_addr; 169 if (0 > setsockopt(rip_sock, 170 IPPROTO_IP, IP_MULTICAST_IF, 171 &tgt_mcast, 172 sizeof(tgt_mcast))) { 173 serrno = errno; 174 LOGERR("setsockopt(rip_sock," 175 "IP_MULTICAST_IF)"); 176 errno = serrno; 177 ifp = 0; 178 return -1; 179 } 180 rip_sock_mcast = ifp; 181 } 182 sin.sin_addr.s_addr = htonl(INADDR_RIP_GROUP); 183 } 184 break; 185 186 case NO_OUT_MULTICAST: 187 case NO_OUT_RIPV2: 188 default: 189 #ifdef DEBUG 190 abort(); 191 #endif 192 return -1; 193 } 194 195 trace_rip(msg, "to", &sin, ifp, buf, size); 196 197 res = sendto(soc, buf, size, flags, 198 (struct sockaddr *)&sin, sizeof(sin)); 199 if (res < 0 200 && (ifp == 0 || !(ifp->int_state & IS_BROKE))) { 201 serrno = errno; 202 msglog("%s sendto(%s%s%s.%d): %s", msg, 203 ifp != 0 ? ifp->int_name : "", 204 ifp != 0 ? ", " : "", 205 inet_ntoa(sin.sin_addr), 206 ntohs(sin.sin_port), 207 strerror(errno)); 208 errno = serrno; 209 } 210 211 return res; 212 } 213 214 215 /* Find the first key for a packet to send. 216 * Try for a key that is eligible and has not expired, but settle for 217 * the last key if they have all expired. 218 * If no key is ready yet, give up. 219 */ 220 struct auth * 221 find_auth(struct interface *ifp) 222 { 223 struct auth *ap, *res; 224 int i; 225 226 227 if (ifp == 0) 228 return 0; 229 230 res = 0; 231 ap = ifp->int_auth; 232 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) { 233 /* stop looking after the last key */ 234 if (ap->type == RIP_AUTH_NONE) 235 break; 236 237 /* ignore keys that are not ready yet */ 238 if ((u_long)ap->start > (u_long)clk.tv_sec) 239 continue; 240 241 if ((u_long)ap->end < (u_long)clk.tv_sec) { 242 /* note best expired password as a fall-back */ 243 if (res == 0 || (u_long)ap->end > (u_long)res->end) 244 res = ap; 245 continue; 246 } 247 248 /* note key with the best future */ 249 if (res == 0 || (u_long)res->end < (u_long)ap->end) 250 res = ap; 251 } 252 return res; 253 } 254 255 256 void 257 clr_ws_buf(struct ws_buf *wb, 258 struct auth *ap) 259 { 260 struct netauth *na; 261 262 wb->lim = wb->base + NETS_LEN; 263 wb->n = wb->base; 264 memset(wb->n, 0, NETS_LEN*sizeof(*wb->n)); 265 266 /* (start to) install authentication if appropriate 267 */ 268 if (ap == 0) 269 return; 270 271 na = (struct netauth*)wb->n; 272 if (ap->type == RIP_AUTH_PW) { 273 na->a_family = RIP_AF_AUTH; 274 na->a_type = RIP_AUTH_PW; 275 memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw)); 276 wb->n++; 277 278 } else if (ap->type == RIP_AUTH_MD5) { 279 na->a_family = RIP_AF_AUTH; 280 na->a_type = RIP_AUTH_MD5; 281 na->au.a_md5.md5_keyid = ap->keyid; 282 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_LEN; 283 na->au.a_md5.md5_seqno = htonl(clk.tv_sec); 284 wb->n++; 285 wb->lim--; /* make room for trailer */ 286 } 287 } 288 289 290 void 291 end_md5_auth(struct ws_buf *wb, 292 struct auth *ap) 293 { 294 struct netauth *na, *na2; 295 MD5_CTX md5_ctx; 296 int len; 297 298 299 na = (struct netauth*)wb->base; 300 na2 = (struct netauth*)wb->n; 301 len = (char *)na2-(char *)wb->buf; 302 na2->a_family = RIP_AF_AUTH; 303 na2->a_type = htons(1); 304 na->au.a_md5.md5_pkt_len = htons(len); 305 MD5Init(&md5_ctx); 306 MD5Update(&md5_ctx, (u_char *)wb->buf, len); 307 MD5Update(&md5_ctx, ap->key, RIP_AUTH_MD5_LEN); 308 MD5Final(na2->au.au_pw, &md5_ctx); 309 wb->n++; 310 } 311 312 313 /* Send the buffer 314 */ 315 static void 316 supply_write(struct ws_buf *wb) 317 { 318 /* Output multicast only if legal. 319 * If we would multicast and it would be illegal, then discard the 320 * packet. 321 */ 322 switch (wb->type) { 323 case NO_OUT_MULTICAST: 324 trace_pkt("skip multicast to %s because impossible", 325 naddr_ntoa(ws.to.sin_addr.s_addr)); 326 break; 327 case NO_OUT_RIPV2: 328 break; 329 default: 330 if (ws.a != 0 && ws.a->type == RIP_AUTH_MD5) 331 end_md5_auth(wb,ws.a); 332 if (output(wb->type, &ws.to, ws.ifp, wb->buf, 333 ((char *)wb->n - (char*)wb->buf)) < 0 334 && ws.ifp != 0) 335 if_sick(ws.ifp); 336 ws.npackets++; 337 break; 338 } 339 340 clr_ws_buf(wb,ws.a); 341 } 342 343 344 /* put an entry into the packet 345 */ 346 static void 347 supply_out(struct ag_info *ag) 348 { 349 int i; 350 naddr mask, v1_mask, dst_h, ddst_h = 0; 351 struct ws_buf *wb; 352 353 354 /* Skip this route if doing a flash update and it and the routes 355 * it aggregates have not changed recently. 356 */ 357 if (ag->ag_seqno < update_seqno 358 && (ws.state & WS_ST_FLASH)) 359 return; 360 361 dst_h = ag->ag_dst_h; 362 mask = ag->ag_mask; 363 v1_mask = ripv1_mask_host(htonl(dst_h), 364 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0); 365 i = 0; 366 367 /* If we are sending RIPv2 packets that cannot (or must not) be 368 * heard by RIPv1 listeners, do not worry about sub- or supernets. 369 * Subnets (from other networks) can only be sent via multicast. 370 * A pair of subnet routes might have been promoted so that they 371 * are legal to send by RIPv1. 372 * If RIPv1 is off, use the multicast buffer. 373 */ 374 if ((ws.state & WS_ST_RIP2_ALL) 375 || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) { 376 /* use the RIPv2-only buffer */ 377 wb = &v2buf; 378 379 } else { 380 /* use the RIPv1-or-RIPv2 buffer */ 381 wb = &v12buf; 382 383 /* Convert supernet route into corresponding set of network 384 * routes for RIPv1, but leave non-contiguous netmasks 385 * to ag_check(). 386 */ 387 if (v1_mask > mask 388 && mask + (mask & -mask) == 0) { 389 ddst_h = v1_mask & -v1_mask; 390 i = (v1_mask & ~mask)/ddst_h; 391 392 if (i > ws.gen_limit) { 393 /* Punt if we would have to generate an 394 * unreasonable number of routes. 395 */ 396 if (TRACECONTENTS) 397 trace_misc("sending %s-->%s as 1" 398 " instead of %d routes", 399 addrname(htonl(dst_h), mask, 400 1), 401 naddr_ntoa(ws.to.sin_addr 402 .s_addr), 403 i+1); 404 i = 0; 405 406 } else { 407 mask = v1_mask; 408 ws.gen_limit -= i; 409 } 410 } 411 } 412 413 do { 414 wb->n->n_family = RIP_AF_INET; 415 wb->n->n_dst = htonl(dst_h); 416 /* If the route is from router-discovery or we are 417 * shutting down, admit only a bad metric. 418 */ 419 wb->n->n_metric = ((stopint || ag->ag_metric < 1) 420 ? HOPCNT_INFINITY 421 : ag->ag_metric); 422 HTONL(wb->n->n_metric); 423 /* Any non-zero bits in the supposedly unused RIPv1 fields 424 * cause the old `routed` to ignore the route. 425 * That means the mask and so forth cannot be sent 426 * in the hybrid RIPv1/RIPv2 mode. 427 */ 428 if (ws.state & WS_ST_RIP2_ALL) { 429 if (ag->ag_nhop != 0 430 && ((ws.state & WS_ST_QUERY) 431 || (ag->ag_nhop != ws.ifp->int_addr 432 && on_net(ag->ag_nhop, 433 ws.ifp->int_net, 434 ws.ifp->int_mask)))) 435 wb->n->n_nhop = ag->ag_nhop; 436 wb->n->n_mask = htonl(mask); 437 wb->n->n_tag = ag->ag_tag; 438 } 439 dst_h += ddst_h; 440 441 if (++wb->n >= wb->lim) 442 supply_write(wb); 443 } while (i-- != 0); 444 } 445 446 447 /* supply one route from the table 448 */ 449 /* ARGSUSED */ 450 static int 451 walk_supply(struct radix_node *rn, 452 struct walkarg *argp UNUSED) 453 { 454 #define RT ((struct rt_entry *)rn) 455 u_short ags; 456 char metric, pref; 457 naddr dst, nhop; 458 struct rt_spare *rts; 459 int i; 460 461 462 /* Do not advertise external remote interfaces or passive interfaces. 463 */ 464 if ((RT->rt_state & RS_IF) 465 && RT->rt_ifp != 0 466 && (RT->rt_ifp->int_if_flags & IS_PASSIVE) 467 && !(RT->rt_state & RS_MHOME)) 468 return 0; 469 470 /* If being quiet about our ability to forward, then 471 * do not say anything unless responding to a query, 472 * except about our main interface. 473 */ 474 if (!supplier && !(ws.state & WS_ST_QUERY) 475 && !(RT->rt_state & RS_MHOME)) 476 return 0; 477 478 dst = RT->rt_dst; 479 480 /* do not collide with the fake default route */ 481 if (dst == RIP_DEFAULT 482 && (ws.state & WS_ST_DEFAULT)) 483 return 0; 484 485 if (RT->rt_state & RS_NET_SYN) { 486 if (RT->rt_state & RS_NET_INT) { 487 /* Do not send manual synthetic network routes 488 * into the subnet. 489 */ 490 if (on_net(ws.to.sin_addr.s_addr, 491 ntohl(dst), RT->rt_mask)) 492 return 0; 493 494 } else { 495 /* Do not send automatic synthetic network routes 496 * if they are not needed because no RIPv1 listeners 497 * can hear them. 498 */ 499 if (ws.state & WS_ST_RIP2_ALL) 500 return 0; 501 502 /* Do not send automatic synthetic network routes to 503 * the real subnet. 504 */ 505 if (on_net(ws.to.sin_addr.s_addr, 506 ntohl(dst), RT->rt_mask)) 507 return 0; 508 } 509 nhop = 0; 510 511 } else { 512 /* Advertise the next hop if this is not a route for one 513 * of our interfaces and the next hop is on the same 514 * network as the target. 515 * The final determination is made by supply_out(). 516 */ 517 if (!(RT->rt_state & RS_IF) 518 && RT->rt_gate != myaddr 519 && RT->rt_gate != loopaddr) 520 nhop = RT->rt_gate; 521 else 522 nhop = 0; 523 } 524 525 metric = RT->rt_metric; 526 ags = 0; 527 528 if (RT->rt_state & RS_MHOME) { 529 /* retain host route of multi-homed servers */ 530 ; 531 532 } else if (RT_ISHOST(RT)) { 533 /* We should always suppress (into existing network routes) 534 * the host routes for the local end of our point-to-point 535 * links. 536 * If we are suppressing host routes in general, then do so. 537 * Avoid advertising host routes onto their own network, 538 * where they should be handled by proxy-ARP. 539 */ 540 if ((RT->rt_state & RS_LOCAL) 541 || ridhosts 542 || on_net(dst, ws.to_net, ws.to_mask)) 543 ags |= AGS_SUPPRESS; 544 545 /* Aggregate stray host routes into network routes if allowed. 546 * We cannot aggregate host routes into small network routes 547 * without confusing RIPv1 listeners into thinking the 548 * network routes are host routes. 549 */ 550 if ((ws.state & WS_ST_AG) 551 && !(ws.state & WS_ST_RIP2_ALL)) 552 ags |= AGS_AGGREGATE; 553 554 } else { 555 /* Always suppress network routes into other, existing 556 * network routes 557 */ 558 ags |= AGS_SUPPRESS; 559 560 /* Generate supernets if allowed. 561 * If we can be heard by RIPv1 systems, we will 562 * later convert back to ordinary nets. 563 * This unifies dealing with received supernets. 564 */ 565 if ((ws.state & WS_ST_AG) 566 && ((RT->rt_state & RS_SUBNET) 567 || (ws.state & WS_ST_SUPER_AG))) 568 ags |= AGS_AGGREGATE; 569 } 570 571 /* Do not send RIPv1 advertisements of subnets to other 572 * networks. If possible, multicast them by RIPv2. 573 */ 574 if ((RT->rt_state & RS_SUBNET) 575 && !(ws.state & WS_ST_RIP2_ALL) 576 && !on_net(dst, ws.to_std_net, ws.to_std_mask)) 577 ags |= AGS_RIPV2 | AGS_AGGREGATE; 578 579 580 /* Do not send a route back to where it came from, except in 581 * response to a query. This is "split-horizon". That means not 582 * advertising back to the same network and so via the same interface. 583 * 584 * We want to suppress routes that might have been fragmented 585 * from this route by a RIPv1 router and sent back to us, and so we 586 * cannot forget this route here. Let the split-horizon route 587 * suppress the fragmented routes and then itself be forgotten. 588 * 589 * Include the routes for both ends of point-to-point interfaces 590 * among those suppressed by split-horizon, since the other side 591 * should knows them as well as we do. 592 * 593 * Notice spare routes with the same metric that we are about to 594 * advertise, to split the horizon on redundant, inactive paths. 595 */ 596 if (ws.ifp != 0 597 && !(ws.state & WS_ST_QUERY) 598 && (ws.state & WS_ST_TO_ON_NET) 599 && (!(RT->rt_state & RS_IF) 600 || ws.ifp->int_if_flags & IFF_POINTOPOINT)) { 601 for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) { 602 if (rts->rts_metric > metric 603 || rts->rts_ifp != ws.ifp) 604 continue; 605 606 /* If we do not mark the route with AGS_SPLIT_HZ here, 607 * it will be poisoned-reverse, or advertised back 608 * toward its source with an infinite metric. 609 * If we have recently advertised the route with a 610 * better metric than we now have, then we should 611 * poison-reverse the route before suppressing it for 612 * split-horizon. 613 * 614 * In almost all cases, if there is no spare for the 615 * route then it is either old and dead or a brand 616 * new route. If it is brand new, there is no need 617 * for poison-reverse. If it is old and dead, it 618 * is already poisoned. 619 */ 620 if (RT->rt_poison_time < now_expire 621 || RT->rt_poison_metric >= metric 622 || RT->rt_spares[1].rts_gate == 0) { 623 ags |= AGS_SPLIT_HZ; 624 ags &= ~AGS_SUPPRESS; 625 } 626 metric = HOPCNT_INFINITY; 627 break; 628 } 629 } 630 631 /* Keep track of the best metric with which the 632 * route has been advertised recently. 633 */ 634 if (RT->rt_poison_metric >= metric 635 || RT->rt_poison_time < now_expire) { 636 RT->rt_poison_time = now.tv_sec; 637 RT->rt_poison_metric = metric; 638 } 639 640 /* Adjust the outgoing metric by the cost of the link. 641 * Avoid aggregation when a route is counting to infinity. 642 */ 643 pref = RT->rt_poison_metric + ws.metric; 644 metric += ws.metric; 645 646 /* Do not advertise stable routes that will be ignored, 647 * unless we are answering a query. 648 * If the route recently was advertised with a metric that 649 * would have been less than infinity through this interface, 650 * we need to continue to advertise it in order to poison it. 651 */ 652 if (metric >= HOPCNT_INFINITY) { 653 if (!(ws.state & WS_ST_QUERY) 654 && (pref >= HOPCNT_INFINITY 655 || RT->rt_poison_time < now_garbage)) 656 return 0; 657 658 metric = HOPCNT_INFINITY; 659 } 660 661 ag_check(dst, RT->rt_mask, 0, nhop, metric, pref, 662 RT->rt_seqno, RT->rt_tag, ags, supply_out); 663 return 0; 664 #undef RT 665 } 666 667 668 /* Supply dst with the contents of the routing tables. 669 * If this won't fit in one packet, chop it up into several. 670 */ 671 void 672 supply(struct sockaddr_in *dst, 673 struct interface *ifp, /* output interface */ 674 enum output_type type, 675 int flash, /* 1=flash update */ 676 int vers, /* RIP version */ 677 int passwd_ok) /* OK to include cleartext password */ 678 { 679 struct rt_entry *rt; 680 int def_metric; 681 682 683 ws.state = 0; 684 ws.gen_limit = 1024; 685 686 ws.to = *dst; 687 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr); 688 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask; 689 690 if (ifp != 0) { 691 ws.to_mask = ifp->int_mask; 692 ws.to_net = ifp->int_net; 693 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask)) 694 ws.state |= WS_ST_TO_ON_NET; 695 696 } else { 697 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0); 698 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask; 699 rt = rtfind(dst->sin_addr.s_addr); 700 if (rt) 701 ifp = rt->rt_ifp; 702 } 703 704 ws.npackets = 0; 705 if (flash) 706 ws.state |= WS_ST_FLASH; 707 708 if ((ws.ifp = ifp) == 0) { 709 ws.metric = 1; 710 } else { 711 /* Adjust the advertised metric by the outgoing interface 712 * metric. 713 */ 714 ws.metric = ifp->int_metric+1; 715 } 716 717 ripv12_buf.rip.rip_vers = vers; 718 719 switch (type) { 720 case OUT_MULTICAST: 721 if (ifp->int_if_flags & IFF_MULTICAST) 722 v2buf.type = OUT_MULTICAST; 723 else 724 v2buf.type = NO_OUT_MULTICAST; 725 v12buf.type = OUT_BROADCAST; 726 break; 727 728 case OUT_QUERY: 729 ws.state |= WS_ST_QUERY; 730 /* fall through */ 731 case OUT_BROADCAST: 732 case OUT_UNICAST: 733 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2; 734 v12buf.type = type; 735 break; 736 737 case NO_OUT_MULTICAST: 738 case NO_OUT_RIPV2: 739 break; /* no output */ 740 } 741 742 if (vers == RIPv2) { 743 /* full RIPv2 only if cannot be heard by RIPv1 listeners */ 744 if (type != OUT_BROADCAST) 745 ws.state |= WS_ST_RIP2_ALL; 746 if ((ws.state & WS_ST_QUERY) 747 || !(ws.state & WS_ST_TO_ON_NET)) { 748 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG); 749 } else if (ifp == 0 || !(ifp->int_state & IS_NO_AG)) { 750 ws.state |= WS_ST_AG; 751 if (type != OUT_BROADCAST 752 && (ifp == 0 753 || !(ifp->int_state & IS_NO_SUPER_AG))) 754 ws.state |= WS_ST_SUPER_AG; 755 } 756 } 757 758 ws.a = (vers == RIPv2) ? find_auth(ifp) : 0; 759 if (!passwd_ok && ws.a != 0 && ws.a->type == RIP_AUTH_PW) 760 ws.a = 0; 761 clr_ws_buf(&v12buf,ws.a); 762 clr_ws_buf(&v2buf,ws.a); 763 764 /* Fake a default route if asked and if there is not already 765 * a better, real default route. 766 */ 767 if (supplier && (def_metric = ifp->int_d_metric) != 0) { 768 if (0 == (rt = rtget(RIP_DEFAULT, 0)) 769 || rt->rt_metric+ws.metric >= def_metric) { 770 ws.state |= WS_ST_DEFAULT; 771 ag_check(0, 0, 0, 0, def_metric, def_metric, 772 0, 0, 0, supply_out); 773 } else { 774 def_metric = rt->rt_metric+ws.metric; 775 } 776 777 /* If both RIPv2 and the poor-man's router discovery 778 * kludge are on, arrange to advertise an extra 779 * default route via RIPv1. 780 */ 781 if ((ws.state & WS_ST_RIP2_ALL) 782 && (ifp->int_state & IS_PM_RDISC)) { 783 ripv12_buf.rip.rip_vers = RIPv1; 784 v12buf.n->n_family = RIP_AF_INET; 785 v12buf.n->n_dst = htonl(RIP_DEFAULT); 786 v12buf.n->n_metric = htonl(def_metric); 787 v12buf.n++; 788 } 789 } 790 791 (void)rn_walktree(rhead, walk_supply, 0); 792 ag_flush(0,0,supply_out); 793 794 /* Flush the packet buffers, provided they are not empty and 795 * do not contain only the password. 796 */ 797 if (v12buf.n != v12buf.base 798 && (v12buf.n > v12buf.base+1 799 || v12buf.base->n_family != RIP_AF_AUTH)) 800 supply_write(&v12buf); 801 if (v2buf.n != v2buf.base 802 && (v2buf.n > v2buf.base+1 803 || v2buf.base->n_family != RIP_AF_AUTH)) 804 supply_write(&v2buf); 805 806 /* If we sent nothing and this is an answer to a query, send 807 * an empty buffer. 808 */ 809 if (ws.npackets == 0 810 && (ws.state & WS_ST_QUERY)) 811 supply_write(&v12buf); 812 } 813 814 815 /* send all of the routing table or just do a flash update 816 */ 817 void 818 rip_bcast(int flash) 819 { 820 #ifdef _HAVE_SIN_LEN 821 static struct sockaddr_in dst = {sizeof(dst), AF_INET}; 822 #else 823 static struct sockaddr_in dst = {AF_INET}; 824 #endif 825 struct interface *ifp; 826 enum output_type type; 827 int vers; 828 struct timeval rtime; 829 830 831 need_flash = 0; 832 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME); 833 no_flash = rtime; 834 timevaladd(&no_flash, &now); 835 836 if (rip_sock < 0) 837 return; 838 839 trace_act("send %s and inhibit dynamic updates for %.3f sec", 840 flash ? "dynamic update" : "all routes", 841 rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0); 842 843 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 844 /* Skip interfaces not doing RIP. 845 * Do try broken interfaces to see if they have healed. 846 */ 847 if (IS_RIP_OUT_OFF(ifp->int_state)) 848 continue; 849 850 /* skip turned off interfaces */ 851 if (!iff_up(ifp->int_if_flags)) 852 continue; 853 854 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1; 855 856 if (ifp->int_if_flags & IFF_BROADCAST) { 857 /* ordinary, hardware interface */ 858 dst.sin_addr.s_addr = ifp->int_brdaddr; 859 860 if (vers == RIPv2 861 && !(ifp->int_state & IS_NO_RIP_MCAST)) { 862 type = OUT_MULTICAST; 863 } else { 864 type = OUT_BROADCAST; 865 } 866 867 } else if (ifp->int_if_flags & IFF_POINTOPOINT) { 868 /* point-to-point hardware interface */ 869 dst.sin_addr.s_addr = ifp->int_dstaddr; 870 type = OUT_UNICAST; 871 872 } else if (ifp->int_state & IS_REMOTE) { 873 /* remote interface */ 874 dst.sin_addr.s_addr = ifp->int_addr; 875 type = OUT_UNICAST; 876 877 } else { 878 /* ATM, HIPPI, etc. */ 879 continue; 880 } 881 882 supply(&dst, ifp, type, flash, vers, 1); 883 } 884 885 update_seqno++; /* all routes are up to date */ 886 } 887 888 889 /* Ask for routes 890 * Do it only once to an interface, and not even after the interface 891 * was broken and recovered. 892 */ 893 void 894 rip_query(void) 895 { 896 #ifdef _HAVE_SIN_LEN 897 static struct sockaddr_in dst = {sizeof(dst), AF_INET}; 898 #else 899 static struct sockaddr_in dst = {AF_INET}; 900 #endif 901 struct interface *ifp; 902 struct rip buf; 903 enum output_type type; 904 905 906 if (rip_sock < 0) 907 return; 908 909 memset(&buf, 0, sizeof(buf)); 910 911 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 912 /* Skip interfaces those already queried. 913 * Do not ask via interfaces through which we don't 914 * accept input. Do not ask via interfaces that cannot 915 * send RIP packets. 916 * Do try broken interfaces to see if they have healed. 917 */ 918 if (IS_RIP_IN_OFF(ifp->int_state) 919 || ifp->int_query_time != NEVER) 920 continue; 921 922 /* skip turned off interfaces */ 923 if (!iff_up(ifp->int_if_flags)) 924 continue; 925 926 buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1; 927 buf.rip_cmd = RIPCMD_REQUEST; 928 buf.rip_nets[0].n_family = RIP_AF_UNSPEC; 929 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY); 930 931 /* Send a RIPv1 query only if allowed and if we will 932 * listen to RIPv1 routers. 933 */ 934 if ((ifp->int_state & IS_NO_RIPV1_OUT) 935 || (ifp->int_state & IS_NO_RIPV1_IN)) { 936 buf.rip_vers = RIPv2; 937 } else { 938 buf.rip_vers = RIPv1; 939 } 940 941 if (ifp->int_if_flags & IFF_BROADCAST) { 942 /* ordinary, hardware interface */ 943 dst.sin_addr.s_addr = ifp->int_brdaddr; 944 945 /* Broadcast RIPv1 queries and RIPv2 queries 946 * when the hardware cannot multicast. 947 */ 948 if (buf.rip_vers == RIPv2 949 && (ifp->int_if_flags & IFF_MULTICAST) 950 && !(ifp->int_state & IS_NO_RIP_MCAST)) { 951 type = OUT_MULTICAST; 952 } else { 953 type = OUT_BROADCAST; 954 } 955 956 } else if (ifp->int_if_flags & IFF_POINTOPOINT) { 957 /* point-to-point hardware interface */ 958 dst.sin_addr.s_addr = ifp->int_dstaddr; 959 type = OUT_UNICAST; 960 961 } else if (ifp->int_state & IS_REMOTE) { 962 /* remote interface */ 963 dst.sin_addr.s_addr = ifp->int_addr; 964 type = OUT_UNICAST; 965 966 } else { 967 /* ATM, HIPPI, etc. */ 968 continue; 969 } 970 971 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL; 972 if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0) 973 if_sick(ifp); 974 } 975 } 976
Indexes created Sun Sep 28 12:09:53 GMT 2025