1 /* $NetBSD: output.c,v 1.25 2009/10/26 02:53:15 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 #include "defs.h" 37 38 #ifdef __NetBSD__ 39 __RCSID("$NetBSD: output.c,v 1.25 2009/10/26 02:53:15 christos Exp $"); 40 #elif defined(__FreeBSD__) 41 __RCSID("$FreeBSD$"); 42 #else 43 __RCSID("Revision: 2.27 "); 44 #ident "Revision: 2.27 " 45 #endif 46 47 48 u_int update_seqno; 49 50 51 /* walk the tree of routes with this for output 52 */ 53 struct { 54 struct sockaddr_in to; 55 naddr to_mask; 56 naddr to_net; 57 naddr to_std_mask; 58 naddr to_std_net; 59 struct interface *ifp; /* usually output interface */ 60 struct auth *a; 61 char metric; /* adjust metrics by interface */ 62 int npackets; 63 int gen_limit; 64 u_int state; 65 #define WS_ST_FLASH 0x001 /* send only changed routes */ 66 #define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */ 67 #define WS_ST_AG 0x004 /* ok to aggregate subnets */ 68 #define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */ 69 #define WS_ST_QUERY 0x010 /* responding to a query */ 70 #define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */ 71 #define WS_ST_DEFAULT 0x040 /* faking a default */ 72 } ws; 73 74 /* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */ 75 struct ws_buf v12buf; 76 union pkt_buf ripv12_buf; 77 78 /* Another for only RIPv2 listeners */ 79 struct ws_buf v2buf; 80 union pkt_buf rip_v2_buf; 81 82 83 84 void 85 bufinit(void) 86 { 87 ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE; 88 v12buf.buf = &ripv12_buf.rip; 89 v12buf.base = &v12buf.buf->rip_nets[0]; 90 91 rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE; 92 rip_v2_buf.rip.rip_vers = RIPv2; 93 v2buf.buf = &rip_v2_buf.rip; 94 v2buf.base = &v2buf.buf->rip_nets[0]; 95 } 96 97 98 /* Send the contents of the global buffer via the non-multicast socket 99 */ 100 int /* <0 on failure */ 101 output(enum output_type type, 102 struct sockaddr_in *dst, /* send to here */ 103 struct interface *ifp, 104 struct rip *buf, 105 int size) /* this many bytes */ 106 { 107 struct sockaddr_in osin; 108 int flags; 109 const char *msg; 110 int res; 111 naddr tgt_mcast; 112 int soc; 113 int serrno; 114 115 osin = *dst; 116 if (osin.sin_port == 0) 117 osin.sin_port = htons(RIP_PORT); 118 #ifdef _HAVE_SIN_LEN 119 if (osin.sin_len == 0) 120 osin.sin_len = sizeof(osin); 121 #endif 122 123 soc = rip_sock; 124 flags = 0; 125 126 switch (type) { 127 case OUT_QUERY: 128 msg = "Answer Query"; 129 if (soc < 0) 130 soc = ifp->int_rip_sock; 131 break; 132 case OUT_UNICAST: 133 msg = "Send"; 134 if (soc < 0) 135 soc = ifp->int_rip_sock; 136 flags = MSG_DONTROUTE; 137 break; 138 case OUT_BROADCAST: 139 if (ifp->int_if_flags & IFF_POINTOPOINT) { 140 msg = "Send"; 141 } else { 142 msg = "Send bcast"; 143 } 144 flags = MSG_DONTROUTE; 145 break; 146 case OUT_MULTICAST: 147 if ((ifp->int_if_flags & IFF_POINTOPOINT) 148 && !(ifp->int_if_flags & IFF_MULTICAST)) { 149 msg = "Send pt-to-pt"; 150 } else if (ifp->int_state & IS_DUP) { 151 trace_act("abort multicast output via %s" 152 " with duplicate address", 153 ifp->int_name); 154 return 0; 155 } else { 156 msg = "Send mcast"; 157 if (rip_sock_mcast != ifp) { 158 #ifdef MCAST_IFINDEX 159 /* specify ifindex */ 160 tgt_mcast = htonl(ifp->int_index); 161 #else 162 #ifdef MCAST_PPP_BUG 163 /* Do not specify the primary interface 164 * explicitly if we have the multicast 165 * point-to-point kernel bug, since the 166 * kernel will do the wrong thing if the 167 * local address of a point-to-point link 168 * is the same as the address of an ordinary 169 * interface. 170 */ 171 if (ifp->int_addr == myaddr) { 172 tgt_mcast = 0; 173 } else 174 #endif 175 tgt_mcast = ifp->int_addr; 176 #endif 177 if (0 > setsockopt(rip_sock, 178 IPPROTO_IP, IP_MULTICAST_IF, 179 &tgt_mcast, 180 sizeof(tgt_mcast))) { 181 serrno = errno; 182 LOGERR("setsockopt(rip_sock," 183 "IP_MULTICAST_IF)"); 184 errno = serrno; 185 ifp = 0; 186 return -1; 187 } 188 rip_sock_mcast = ifp; 189 } 190 osin.sin_addr.s_addr = htonl(INADDR_RIP_GROUP); 191 } 192 break; 193 194 case NO_OUT_MULTICAST: 195 case NO_OUT_RIPV2: 196 default: 197 #ifdef DEBUG 198 abort(); 199 #endif 200 return -1; 201 } 202 203 trace_rip(msg, "to", &osin, ifp, buf, size); 204 205 res = sendto(soc, buf, size, flags, 206 (struct sockaddr *)&osin, sizeof(osin)); 207 if (res < 0 208 && (ifp == 0 || !(ifp->int_state & IS_BROKE))) { 209 serrno = errno; 210 msglog("%s sendto(%s%s%s.%d): %s", msg, 211 ifp != 0 ? ifp->int_name : "", 212 ifp != 0 ? ", " : "", 213 inet_ntoa(osin.sin_addr), 214 ntohs(osin.sin_port), 215 strerror(errno)); 216 errno = serrno; 217 } 218 219 return res; 220 } 221 222 223 /* Find the first key for a packet to send. 224 * Try for a key that is eligible and has not expired, but settle for 225 * the last key if they have all expired. 226 * If no key is ready yet, give up. 227 */ 228 struct auth * 229 find_auth(struct interface *ifp) 230 { 231 struct auth *ap, *res; 232 int i; 233 234 235 if (ifp == 0) 236 return 0; 237 238 res = 0; 239 ap = ifp->int_auth; 240 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) { 241 /* stop looking after the last key */ 242 if (ap->type == RIP_AUTH_NONE) 243 break; 244 245 /* ignore keys that are not ready yet */ 246 if ((u_long)ap->start > (u_long)clk.tv_sec) 247 continue; 248 249 if ((u_long)ap->end < (u_long)clk.tv_sec) { 250 /* note best expired password as a fall-back */ 251 if (res == 0 || (u_long)ap->end > (u_long)res->end) 252 res = ap; 253 continue; 254 } 255 256 /* note key with the best future */ 257 if (res == 0 || (u_long)res->end < (u_long)ap->end) 258 res = ap; 259 } 260 return res; 261 } 262 263 264 void 265 clr_ws_buf(struct ws_buf *wb, 266 struct auth *ap) 267 { 268 struct netauth *na; 269 270 wb->lim = wb->base + NETS_LEN; 271 wb->n = wb->base; 272 memset(wb->n, 0, NETS_LEN*sizeof(*wb->n)); 273 274 /* (start to) install authentication if appropriate 275 */ 276 if (ap == 0) 277 return; 278 279 na = (struct netauth*)wb->n; 280 if (ap->type == RIP_AUTH_PW) { 281 na->a_family = RIP_AF_AUTH; 282 na->a_type = RIP_AUTH_PW; 283 memcpy(na->au.au_pw, ap->key, sizeof(na->au.au_pw)); 284 wb->n++; 285 286 } else if (ap->type == RIP_AUTH_MD5) { 287 na->a_family = RIP_AF_AUTH; 288 na->a_type = RIP_AUTH_MD5; 289 na->au.a_md5.md5_keyid = ap->keyid; 290 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_KEY_LEN; 291 na->au.a_md5.md5_seqno = htonl(clk.tv_sec); 292 wb->n++; 293 wb->lim--; /* make room for trailer */ 294 } 295 } 296 297 298 void 299 end_md5_auth(struct ws_buf *wb, 300 struct auth *ap) 301 { 302 struct netauth *na, *na2; 303 MD5_CTX md5_ctx; 304 int len; 305 306 307 na = (struct netauth*)wb->base; 308 na2 = (struct netauth*)wb->n; 309 len = (char *)na2-(char *)wb->buf; 310 na2->a_family = RIP_AF_AUTH; 311 na2->a_type = htons(1); 312 na->au.a_md5.md5_pkt_len = htons(len); 313 MD5Init(&md5_ctx); 314 MD5Update(&md5_ctx, (u_char *)wb->buf, len + RIP_AUTH_MD5_HASH_XTRA); 315 MD5Update(&md5_ctx, ap->key, RIP_AUTH_MD5_KEY_LEN); 316 MD5Final(na2->au.au_pw, &md5_ctx); 317 wb->n++; 318 } 319 320 321 /* Send the buffer 322 */ 323 static void 324 supply_write(struct ws_buf *wb) 325 { 326 /* Output multicast only if legal. 327 * If we would multicast and it would be illegal, then discard the 328 * packet. 329 */ 330 switch (wb->type) { 331 case NO_OUT_MULTICAST: 332 trace_pkt("skip multicast to %s because impossible", 333 naddr_ntoa(ws.to.sin_addr.s_addr)); 334 break; 335 case NO_OUT_RIPV2: 336 break; 337 default: 338 if (ws.a != 0 && ws.a->type == RIP_AUTH_MD5) 339 end_md5_auth(wb,ws.a); 340 if (output(wb->type, &ws.to, ws.ifp, wb->buf, 341 ((char *)wb->n - (char*)wb->buf)) < 0 342 && ws.ifp != 0) 343 if_sick(ws.ifp); 344 ws.npackets++; 345 break; 346 } 347 348 clr_ws_buf(wb,ws.a); 349 } 350 351 352 /* put an entry into the packet 353 */ 354 static void 355 supply_out(struct ag_info *ag) 356 { 357 int i; 358 naddr mask, v1_mask, dst_h, ddst_h = 0; 359 struct ws_buf *wb; 360 361 362 /* Skip this route if doing a flash update and it and the routes 363 * it aggregates have not changed recently. 364 */ 365 if (ag->ag_seqno < update_seqno 366 && (ws.state & WS_ST_FLASH)) 367 return; 368 369 dst_h = ag->ag_dst_h; 370 mask = ag->ag_mask; 371 v1_mask = ripv1_mask_host(htonl(dst_h), 372 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : 0); 373 i = 0; 374 375 /* If we are sending RIPv2 packets that cannot (or must not) be 376 * heard by RIPv1 listeners, do not worry about sub- or supernets. 377 * Subnets (from other networks) can only be sent via multicast. 378 * A pair of subnet routes might have been promoted so that they 379 * are legal to send by RIPv1. 380 * If RIPv1 is off, use the multicast buffer. 381 */ 382 if ((ws.state & WS_ST_RIP2_ALL) 383 || ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) { 384 /* use the RIPv2-only buffer */ 385 wb = &v2buf; 386 387 } else { 388 /* use the RIPv1-or-RIPv2 buffer */ 389 wb = &v12buf; 390 391 /* Convert supernet route into corresponding set of network 392 * routes for RIPv1, but leave non-contiguous netmasks 393 * to ag_check(). 394 */ 395 if (v1_mask > mask 396 && mask + (mask & -mask) == 0) { 397 ddst_h = v1_mask & -v1_mask; 398 i = (v1_mask & ~mask)/ddst_h; 399 400 if (i > ws.gen_limit) { 401 /* Punt if we would have to generate an 402 * unreasonable number of routes. 403 */ 404 if (TRACECONTENTS) 405 trace_misc("sending %s-->%s as 1" 406 " instead of %d routes", 407 addrname(htonl(dst_h), mask, 408 1), 409 naddr_ntoa(ws.to.sin_addr 410 .s_addr), 411 i+1); 412 i = 0; 413 414 } else { 415 mask = v1_mask; 416 ws.gen_limit -= i; 417 } 418 } 419 } 420 421 do { 422 wb->n->n_family = RIP_AF_INET; 423 wb->n->n_dst = htonl(dst_h); 424 /* If the route is from router-discovery or we are 425 * shutting down, admit only a bad metric. 426 */ 427 wb->n->n_metric = ((stopint || ag->ag_metric < 1) 428 ? HOPCNT_INFINITY 429 : ag->ag_metric); 430 wb->n->n_metric = htonl(wb->n->n_metric); 431 /* Any non-zero bits in the supposedly unused RIPv1 fields 432 * cause the old `routed` to ignore the route. 433 * That means the mask and so forth cannot be sent 434 * in the hybrid RIPv1/RIPv2 mode. 435 */ 436 if (ws.state & WS_ST_RIP2_ALL) { 437 if (ag->ag_nhop != 0 438 && ((ws.state & WS_ST_QUERY) 439 || (ag->ag_nhop != ws.ifp->int_addr 440 && on_net(ag->ag_nhop, 441 ws.ifp->int_net, 442 ws.ifp->int_mask)))) 443 wb->n->n_nhop = ag->ag_nhop; 444 wb->n->n_mask = htonl(mask); 445 wb->n->n_tag = ag->ag_tag; 446 } 447 dst_h += ddst_h; 448 449 if (++wb->n >= wb->lim) 450 supply_write(wb); 451 } while (i-- != 0); 452 } 453 454 455 /* supply one route from the table 456 */ 457 /* ARGSUSED */ 458 static int 459 walk_supply(struct radix_node *rn, 460 struct walkarg *argp UNUSED) 461 { 462 #define RT ((struct rt_entry *)rn) 463 u_short ags; 464 char metric, pref; 465 naddr dst, nhop; 466 struct rt_spare *rts; 467 int i; 468 469 470 /* Do not advertise external remote interfaces or passive interfaces. 471 */ 472 if ((RT->rt_state & RS_IF) 473 && RT->rt_ifp != 0 474 && (RT->rt_ifp->int_state & IS_PASSIVE) 475 && !(RT->rt_state & RS_MHOME)) 476 return 0; 477 478 /* If being quiet about our ability to forward, then 479 * do not say anything unless responding to a query, 480 * except about our main interface. 481 */ 482 if (!supplier && !(ws.state & WS_ST_QUERY) 483 && !(RT->rt_state & RS_MHOME)) 484 return 0; 485 486 dst = RT->rt_dst; 487 488 /* do not collide with the fake default route */ 489 if (dst == RIP_DEFAULT 490 && (ws.state & WS_ST_DEFAULT)) 491 return 0; 492 493 if (RT->rt_state & RS_NET_SYN) { 494 if (RT->rt_state & RS_NET_INT) { 495 /* Do not send manual synthetic network routes 496 * into the subnet. 497 */ 498 if (on_net(ws.to.sin_addr.s_addr, 499 ntohl(dst), RT->rt_mask)) 500 return 0; 501 502 } else { 503 /* Do not send automatic synthetic network routes 504 * if they are not needed because no RIPv1 listeners 505 * can hear them. 506 */ 507 if (ws.state & WS_ST_RIP2_ALL) 508 return 0; 509 510 /* Do not send automatic synthetic network routes to 511 * the real subnet. 512 */ 513 if (on_net(ws.to.sin_addr.s_addr, 514 ntohl(dst), RT->rt_mask)) 515 return 0; 516 } 517 nhop = 0; 518 519 } else { 520 /* Advertise the next hop if this is not a route for one 521 * of our interfaces and the next hop is on the same 522 * network as the target. 523 * The final determination is made by supply_out(). 524 */ 525 if (!(RT->rt_state & RS_IF) 526 && RT->rt_gate != myaddr 527 && RT->rt_gate != loopaddr) 528 nhop = RT->rt_gate; 529 else 530 nhop = 0; 531 } 532 533 metric = RT->rt_metric; 534 ags = 0; 535 536 if (RT->rt_state & RS_MHOME) { 537 /* retain host route of multi-homed servers */ 538 ; 539 540 } else if (RT_ISHOST(RT)) { 541 /* We should always suppress (into existing network routes) 542 * the host routes for the local end of our point-to-point 543 * links. 544 * If we are suppressing host routes in general, then do so. 545 * Avoid advertising host routes onto their own network, 546 * where they should be handled by proxy-ARP. 547 */ 548 if ((RT->rt_state & RS_LOCAL) 549 || ridhosts 550 || on_net(dst, ws.to_net, ws.to_mask)) 551 ags |= AGS_SUPPRESS; 552 553 /* Aggregate stray host routes into network routes if allowed. 554 * We cannot aggregate host routes into small network routes 555 * without confusing RIPv1 listeners into thinking the 556 * network routes are host routes. 557 */ 558 if ((ws.state & WS_ST_AG) && (ws.state & WS_ST_RIP2_ALL)) 559 ags |= AGS_AGGREGATE; 560 561 } else { 562 /* Always suppress network routes into other, existing 563 * network routes 564 */ 565 ags |= AGS_SUPPRESS; 566 567 /* Generate supernets if allowed. 568 * If we can be heard by RIPv1 systems, we will 569 * later convert back to ordinary nets. 570 * This unifies dealing with received supernets. 571 */ 572 if ((ws.state & WS_ST_AG) 573 && ((RT->rt_state & RS_SUBNET) 574 || (ws.state & WS_ST_SUPER_AG))) 575 ags |= AGS_AGGREGATE; 576 } 577 578 /* Do not send RIPv1 advertisements of subnets to other 579 * networks. If possible, multicast them by RIPv2. 580 */ 581 if ((RT->rt_state & RS_SUBNET) 582 && !(ws.state & WS_ST_RIP2_ALL) 583 && !on_net(dst, ws.to_std_net, ws.to_std_mask)) 584 ags |= AGS_RIPV2 | AGS_AGGREGATE; 585 586 587 /* Do not send a route back to where it came from, except in 588 * response to a query. This is "split-horizon". That means not 589 * advertising back to the same network and so via the same interface. 590 * 591 * We want to suppress routes that might have been fragmented 592 * from this route by a RIPv1 router and sent back to us, and so we 593 * cannot forget this route here. Let the split-horizon route 594 * suppress the fragmented routes and then itself be forgotten. 595 * 596 * Include the routes for both ends of point-to-point interfaces 597 * among those suppressed by split-horizon, since the other side 598 * should knows them as well as we do. 599 * 600 * Notice spare routes with the same metric that we are about to 601 * advertise, to split the horizon on redundant, inactive paths. 602 * 603 * Do not suppress advertisements of interface-related addresses on 604 * non-point-to-point interfaces. This ensures that we have something 605 * to say every 30 seconds to help detect broken Ethernets or 606 * other interfaces where one packet every 30 seconds costs nothing. 607 */ 608 if (ws.ifp != 0 609 && !(ws.state & WS_ST_QUERY) 610 && (ws.state & WS_ST_TO_ON_NET) 611 && (!(RT->rt_state & RS_IF) 612 || ws.ifp->int_if_flags & IFF_POINTOPOINT)) { 613 for (rts = RT->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) { 614 if (rts->rts_metric > metric 615 || rts->rts_ifp != ws.ifp) 616 continue; 617 618 /* If we do not mark the route with AGS_SPLIT_HZ here, 619 * it will be poisoned-reverse, or advertised back 620 * toward its source with an infinite metric. 621 * If we have recently advertised the route with a 622 * better metric than we now have, then we should 623 * poison-reverse the route before suppressing it for 624 * split-horizon. 625 * 626 * In almost all cases, if there is no spare for the 627 * route then it is either old and dead or a brand 628 * new route. If it is brand new, there is no need 629 * for poison-reverse. If it is old and dead, it 630 * is already poisoned. 631 */ 632 if (RT->rt_poison_time < now_expire 633 || RT->rt_poison_metric >= metric 634 || RT->rt_spares[1].rts_gate == 0) { 635 ags |= AGS_SPLIT_HZ; 636 ags &= ~AGS_SUPPRESS; 637 } 638 metric = HOPCNT_INFINITY; 639 break; 640 } 641 } 642 643 /* Keep track of the best metric with which the 644 * route has been advertised recently. 645 */ 646 if (RT->rt_poison_metric >= metric 647 || RT->rt_poison_time < now_expire) { 648 RT->rt_poison_time = now.tv_sec; 649 RT->rt_poison_metric = metric; 650 } 651 652 /* Adjust the outgoing metric by the cost of the link. 653 * Avoid aggregation when a route is counting to infinity. 654 */ 655 pref = RT->rt_poison_metric + ws.metric; 656 metric += ws.metric; 657 658 /* Do not advertise stable routes that will be ignored, 659 * unless we are answering a query. 660 * If the route recently was advertised with a metric that 661 * would have been less than infinity through this interface, 662 * we need to continue to advertise it in order to poison it. 663 */ 664 if (metric >= HOPCNT_INFINITY) { 665 if (!(ws.state & WS_ST_QUERY) 666 && (pref >= HOPCNT_INFINITY 667 || RT->rt_poison_time < now_garbage)) 668 return 0; 669 670 metric = HOPCNT_INFINITY; 671 } 672 673 ag_check(dst, RT->rt_mask, 0, nhop, metric, pref, 674 RT->rt_seqno, RT->rt_tag, ags, supply_out); 675 return 0; 676 #undef RT 677 } 678 679 680 /* Supply dst with the contents of the routing tables. 681 * If this won't fit in one packet, chop it up into several. 682 */ 683 void 684 supply(struct sockaddr_in *dst, 685 struct interface *ifp, /* output interface */ 686 enum output_type type, 687 int flash, /* 1=flash update */ 688 int vers, /* RIP version */ 689 int passwd_ok) /* OK to include cleartext password */ 690 { 691 struct rt_entry *rt; 692 int def_metric; 693 694 695 ws.state = 0; 696 ws.gen_limit = 1024; 697 698 ws.to = *dst; 699 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr); 700 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask; 701 702 if (ifp != 0) { 703 ws.to_mask = ifp->int_mask; 704 ws.to_net = ifp->int_net; 705 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask)) 706 ws.state |= WS_ST_TO_ON_NET; 707 708 } else { 709 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, 0); 710 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask; 711 rt = rtfind(dst->sin_addr.s_addr); 712 if (rt) 713 ifp = rt->rt_ifp; 714 } 715 716 ws.npackets = 0; 717 if (flash) 718 ws.state |= WS_ST_FLASH; 719 720 if ((ws.ifp = ifp) == 0) { 721 ws.metric = 1; 722 } else { 723 /* Adjust the advertised metric by the outgoing interface 724 * metric. 725 */ 726 ws.metric = ifp->int_metric + 1 + ifp->int_adj_outmetric; 727 } 728 729 ripv12_buf.rip.rip_vers = vers; 730 731 switch (type) { 732 case OUT_MULTICAST: 733 if (ifp != NULL && ifp->int_if_flags & IFF_MULTICAST) 734 v2buf.type = OUT_MULTICAST; 735 else 736 v2buf.type = NO_OUT_MULTICAST; 737 v12buf.type = OUT_BROADCAST; 738 break; 739 740 case OUT_QUERY: 741 ws.state |= WS_ST_QUERY; 742 /* fall through */ 743 case OUT_BROADCAST: 744 case OUT_UNICAST: 745 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2; 746 v12buf.type = type; 747 break; 748 749 case NO_OUT_MULTICAST: 750 case NO_OUT_RIPV2: 751 break; /* no output */ 752 } 753 754 if (vers == RIPv2) { 755 /* full RIPv2 only if cannot be heard by RIPv1 listeners */ 756 if (type != OUT_BROADCAST) 757 ws.state |= WS_ST_RIP2_ALL; 758 if ((ws.state & WS_ST_QUERY) 759 || !(ws.state & WS_ST_TO_ON_NET)) { 760 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG); 761 } else if (ifp == 0 || !(ifp->int_state & IS_NO_AG)) { 762 ws.state |= WS_ST_AG; 763 if (type != OUT_BROADCAST 764 && (ifp == 0 765 || !(ifp->int_state & IS_NO_SUPER_AG))) 766 ws.state |= WS_ST_SUPER_AG; 767 } 768 } 769 770 ws.a = (vers == RIPv2) ? find_auth(ifp) : 0; 771 if (!passwd_ok && ws.a != 0 && ws.a->type == RIP_AUTH_PW) 772 ws.a = 0; 773 clr_ws_buf(&v12buf,ws.a); 774 clr_ws_buf(&v2buf,ws.a); 775 776 /* Fake a default route if asked and if there is not already 777 * a better, real default route. 778 */ 779 if (supplier && ifp && (def_metric = ifp->int_d_metric) != 0) { 780 if (0 == (rt = rtget(RIP_DEFAULT, 0)) 781 || rt->rt_metric+ws.metric >= def_metric) { 782 ws.state |= WS_ST_DEFAULT; 783 ag_check(0, 0, 0, 0, def_metric, def_metric, 784 0, 0, 0, supply_out); 785 } else { 786 def_metric = rt->rt_metric+ws.metric; 787 } 788 789 /* If both RIPv2 and the poor-man's router discovery 790 * kludge are on, arrange to advertise an extra 791 * default route via RIPv1. 792 */ 793 if ((ws.state & WS_ST_RIP2_ALL) 794 && (ifp->int_state & IS_PM_RDISC)) { 795 ripv12_buf.rip.rip_vers = RIPv1; 796 v12buf.n->n_family = RIP_AF_INET; 797 v12buf.n->n_dst = htonl(RIP_DEFAULT); 798 v12buf.n->n_metric = htonl(def_metric); 799 v12buf.n++; 800 } 801 } 802 803 (void)rn_walktree(rhead, walk_supply, 0); 804 ag_flush(0,0,supply_out); 805 806 /* Flush the packet buffers, provided they are not empty and 807 * do not contain only the password. 808 */ 809 if (v12buf.n != v12buf.base 810 && (v12buf.n > v12buf.base+1 811 || v12buf.base->n_family != RIP_AF_AUTH)) 812 supply_write(&v12buf); 813 if (v2buf.n != v2buf.base 814 && (v2buf.n > v2buf.base+1 815 || v2buf.base->n_family != RIP_AF_AUTH)) 816 supply_write(&v2buf); 817 818 /* If we sent nothing and this is an answer to a query, send 819 * an empty buffer. 820 */ 821 if (ws.npackets == 0 822 && (ws.state & WS_ST_QUERY)) 823 supply_write(&v12buf); 824 } 825 826 827 /* send all of the routing table or just do a flash update 828 */ 829 void 830 rip_bcast(int flash) 831 { 832 #ifdef _HAVE_SIN_LEN 833 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}}; 834 #else 835 static struct sockaddr_in dst = {AF_INET}; 836 #endif 837 struct interface *ifp; 838 enum output_type type; 839 int vers; 840 struct timeval rtime; 841 842 843 need_flash = 0; 844 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME); 845 no_flash = rtime; 846 timevaladd(&no_flash, &now); 847 848 if (rip_sock < 0) 849 return; 850 851 trace_act("send %s and inhibit dynamic updates for %.3f sec", 852 flash ? "dynamic update" : "all routes", 853 rtime.tv_sec + ((float)rtime.tv_usec)/1000000.0); 854 855 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 856 /* Skip interfaces not doing RIP. 857 * Do try broken interfaces to see if they have healed. 858 */ 859 if (IS_RIP_OUT_OFF(ifp->int_state)) 860 continue; 861 862 /* skip turned off interfaces */ 863 if (!iff_up(ifp->int_if_flags)) 864 continue; 865 866 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1; 867 868 if (ifp->int_if_flags & IFF_BROADCAST) { 869 /* ordinary, hardware interface */ 870 dst.sin_addr.s_addr = ifp->int_brdaddr; 871 872 if (vers == RIPv2 873 && !(ifp->int_state & IS_NO_RIP_MCAST)) { 874 type = OUT_MULTICAST; 875 } else { 876 type = OUT_BROADCAST; 877 } 878 879 } else if (ifp->int_if_flags & IFF_POINTOPOINT) { 880 /* point-to-point hardware interface */ 881 dst.sin_addr.s_addr = ifp->int_dstaddr; 882 /* use multicast if the interface allows (e.g. GRE) */ 883 if (vers == RIPv2 884 && (ifp->int_if_flags & IFF_MULTICAST) 885 && !(ifp->int_state & IS_NO_RIP_MCAST)) { 886 type = OUT_MULTICAST; 887 } else { 888 type = OUT_UNICAST; 889 } 890 891 } else if (ifp->int_state & IS_REMOTE) { 892 /* remote interface */ 893 dst.sin_addr.s_addr = ifp->int_addr; 894 type = OUT_UNICAST; 895 896 } else { 897 /* ATM, HIPPI, etc. */ 898 continue; 899 } 900 901 supply(&dst, ifp, type, flash, vers, 1); 902 } 903 904 update_seqno++; /* all routes are up to date */ 905 } 906 907 908 /* Ask for routes 909 * Do it only once to an interface, and not even after the interface 910 * was broken and recovered. 911 */ 912 void 913 rip_query(void) 914 { 915 #ifdef _HAVE_SIN_LEN 916 static struct sockaddr_in dst = {sizeof(dst), AF_INET, 0, {0}, {0}}; 917 #else 918 static struct sockaddr_in dst = {AF_INET}; 919 #endif 920 struct interface *ifp; 921 struct rip buf; 922 enum output_type type; 923 924 925 if (rip_sock < 0) 926 return; 927 928 memset(&buf, 0, sizeof(buf)); 929 930 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 931 /* Skip interfaces those already queried. 932 * Do not ask via interfaces through which we don't 933 * accept input. Do not ask via interfaces that cannot 934 * send RIP packets. 935 * Do try broken interfaces to see if they have healed. 936 */ 937 if (IS_RIP_IN_OFF(ifp->int_state) 938 || ifp->int_query_time != NEVER) 939 continue; 940 941 /* skip turned off interfaces */ 942 if (!iff_up(ifp->int_if_flags)) 943 continue; 944 945 buf.rip_vers = (ifp->int_state&IS_NO_RIPV1_OUT) ? RIPv2:RIPv1; 946 buf.rip_cmd = RIPCMD_REQUEST; 947 buf.rip_nets[0].n_family = RIP_AF_UNSPEC; 948 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY); 949 950 /* Send a RIPv1 query only if allowed and if we will 951 * listen to RIPv1 routers. 952 */ 953 if ((ifp->int_state & IS_NO_RIPV1_OUT) 954 || (ifp->int_state & IS_NO_RIPV1_IN)) { 955 buf.rip_vers = RIPv2; 956 } else { 957 buf.rip_vers = RIPv1; 958 } 959 960 if (ifp->int_if_flags & IFF_BROADCAST) { 961 /* ordinary, hardware interface */ 962 dst.sin_addr.s_addr = ifp->int_brdaddr; 963 964 /* Broadcast RIPv1 queries and RIPv2 queries 965 * when the hardware cannot multicast. 966 */ 967 if (buf.rip_vers == RIPv2 968 && (ifp->int_if_flags & IFF_MULTICAST) 969 && !(ifp->int_state & IS_NO_RIP_MCAST)) { 970 type = OUT_MULTICAST; 971 } else { 972 type = OUT_BROADCAST; 973 } 974 975 } else if (ifp->int_if_flags & IFF_POINTOPOINT) { 976 /* point-to-point hardware interface */ 977 dst.sin_addr.s_addr = ifp->int_dstaddr; 978 /* use multicast if the interface allows (e.g. GRE) */ 979 if (buf.rip_vers == RIPv2 980 && (ifp->int_if_flags & IFF_MULTICAST) 981 && !(ifp->int_state & IS_NO_RIP_MCAST)) { 982 type = OUT_MULTICAST; 983 } else { 984 type = OUT_UNICAST; 985 } 986 987 } else if (ifp->int_state & IS_REMOTE) { 988 /* remote interface */ 989 dst.sin_addr.s_addr = ifp->int_addr; 990 type = OUT_UNICAST; 991 992 } else { 993 /* ATM, HIPPI, etc. */ 994 continue; 995 } 996 997 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL; 998 if (output(type, &dst, ifp, &buf, sizeof(buf)) < 0) 999 if_sick(ifp); 1000 } 1001 } 1002
Indexes created Sun Sep 21 20:09:37 GMT 2025