1/* 2 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 * 5 * Copyright (c) 1983, 1988, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgment: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * $FreeBSD: src/sbin/routed/output.c,v 1.7 2000/08/11 08:24:38 sheldonh Exp $ 37 */ 38 39#pragma ident "%Z%%M% %I% %E% SMI" 40 41#include "defs.h" 42#include <md5.h> 43#include <alloca.h> 44 45uint_t update_seqno; 46 47 48/* 49 * walk the tree of routes with this for output 50 */ 51static struct { 52 struct sockaddr_in to; 53 in_addr_t to_mask; 54 in_addr_t to_net; 55 in_addr_t to_std_mask; 56 in_addr_t to_std_net; 57 struct interface *ifp; /* usually output interface */ 58 struct auth *a; 59 uint8_t metric; /* adjust metrics by interface */ 60 uint32_t npackets; 61 uint32_t gen_limit; 62#define WS_GEN_LIMIT_MAX 1024 63 uint16_t state; 64#define WS_ST_FLASH 0x001 /* send only changed routes */ 65#define WS_ST_RIP2_ALL 0x002 /* send full featured RIPv2 */ 66#define WS_ST_AG 0x004 /* ok to aggregate subnets */ 67#define WS_ST_SUPER_AG 0x008 /* ok to aggregate networks */ 68#define WS_ST_QUERY 0x010 /* responding to a query */ 69#define WS_ST_TO_ON_NET 0x020 /* sending onto one of our nets */ 70#define WS_ST_DEFAULT 0x040 /* faking a default */ 71} ws; 72 73/* A buffer for what can be heard by both RIPv1 and RIPv2 listeners */ 74struct ws_buf v12buf; 75static union pkt_buf ripv12_buf; 76 77/* Another for only RIPv2 listeners */ 78static struct ws_buf v2buf; 79static union pkt_buf rip_v2_buf; 80 81 82 83void 84bufinit(void) 85{ 86 ripv12_buf.rip.rip_cmd = RIPCMD_RESPONSE; 87 v12buf.buf = &ripv12_buf.rip; 88 v12buf.base = &v12buf.buf->rip_nets[0]; 89 90 rip_v2_buf.rip.rip_cmd = RIPCMD_RESPONSE; 91 rip_v2_buf.rip.rip_vers = RIPv2; 92 v2buf.buf = &rip_v2_buf.rip; 93 v2buf.base = &v2buf.buf->rip_nets[0]; 94} 95 96 97/* 98 * Send the contents of the global buffer via the non-multicast socket 99 */ 100int /* <0 on failure */ 101output(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 sin; 108 int flags; 109 const char *msg; 110 int res; 111 int ifindex; 112 struct in_addr addr; 113 114 sin = *dst; 115 if (sin.sin_port == 0) 116 sin.sin_port = htons(RIP_PORT); 117 118 flags = 0; 119 120 if (ifp == NULL && type == OUT_MULTICAST) { 121 msglog("Cannot send RIP message to %s", 122 inet_ntoa(sin.sin_addr)); 123 return (-1); 124 } 125 126 switch (type) { 127 case OUT_QUERY: 128 msg = "Answer Query"; 129 break; 130 case OUT_UNICAST: 131 msg = "Send"; 132 flags = MSG_DONTROUTE; 133 break; 134 case OUT_BROADCAST: 135 msg = "Send bcast"; 136 break; 137 case OUT_MULTICAST: 138 msg = "Send mcast"; 139 break; 140 141 case NO_OUT_MULTICAST: 142 case NO_OUT_RIPV2: 143 default: 144#ifdef DEBUG 145 abort(); 146#endif 147 return (-1); 148 } 149 150 /* 151 * IP_PKTINFO overrides IP_MULTICAST_IF, so we don't set ifindex 152 * for multicast traffic. 153 */ 154 ifindex = (type != OUT_MULTICAST && type != OUT_QUERY && 155 ifp != NULL && ifp->int_phys != NULL) ? 156 ifp->int_phys->phyi_index : 0; 157 158 if (rip_sock_interface != ifp) { 159 /* 160 * For multicast, we have to choose the source 161 * address. This is either the local address 162 * (non-point-to-point) or the remote address. 163 */ 164 if (ifp != NULL) { 165 addr.s_addr = (ifp->int_if_flags & IFF_POINTOPOINT) ? 166 ifp->int_dstaddr : ifp->int_addr; 167 if (type == OUT_MULTICAST && 168 setsockopt(rip_sock, IPPROTO_IP, 169 IP_MULTICAST_IF, &addr, sizeof (addr)) == -1) { 170 LOGERR("setsockopt(rip_sock, IP_MULTICAST_IF)"); 171 return (-1); 172 } 173 } 174 rip_sock_interface = ifp; 175 } 176 177 trace_rip(msg, "to", &sin, ifp, buf, size); 178 179 res = sendtoif(rip_sock, buf, size, flags, &sin, ifindex); 180 if (res < 0 && (ifp == NULL || !(ifp->int_state & IS_BROKE))) { 181 writelog(LOG_WARNING, "%s sendto(%s%s%s.%d): %s", msg, 182 ifp != NULL ? ifp->int_name : "", 183 ifp != NULL ? ", " : "", 184 inet_ntoa(sin.sin_addr), 185 ntohs(sin.sin_port), 186 rip_strerror(errno)); 187 } 188 189 return (res); 190} 191 192/* 193 * Semantically identical to sendto(), but sends the message through a 194 * specific interface (if ifindex is non-zero) using IP_PKTINFO. 195 */ 196int 197sendtoif(int fd, const void *buf, uint_t bufsize, uint_t flags, 198 struct sockaddr_in *sinp, uint_t ifindex) 199{ 200 struct iovec iov; 201 struct msghdr msg; 202 struct cmsghdr *cmsgp; 203 struct in_pktinfo *ipip; 204 205 iov.iov_base = (void *)buf; 206 iov.iov_len = bufsize; 207 208 (void) memset(&msg, 0, sizeof (struct msghdr)); 209 msg.msg_name = (struct sockaddr *)sinp; 210 msg.msg_namelen = sizeof (struct sockaddr_in); 211 msg.msg_iov = &iov; 212 msg.msg_iovlen = 1; 213 214 if (ifindex != 0) { 215 /* 216 * We can't precisely predict the alignment padding we'll 217 * need, so we allocate the maximum alignment and then 218 * use CMSG_NXTHDR() to fix it up at the end. 219 */ 220 msg.msg_controllen = sizeof (*cmsgp) + _MAX_ALIGNMENT + 221 sizeof (*ipip) + _MAX_ALIGNMENT + sizeof (*cmsgp); 222 msg.msg_control = alloca(msg.msg_controllen); 223 224 cmsgp = CMSG_FIRSTHDR(&msg); 225 ipip = (void *)CMSG_DATA(cmsgp); 226 (void) memset(ipip, 0, sizeof (struct in_pktinfo)); 227 ipip->ipi_ifindex = ifindex; 228 cmsgp->cmsg_len = (caddr_t)(ipip + 1) - (caddr_t)cmsgp; 229 cmsgp->cmsg_type = IP_PKTINFO; 230 cmsgp->cmsg_level = IPPROTO_IP; 231 232 /* 233 * Correct the control message length. 234 */ 235 cmsgp = CMSG_NXTHDR(&msg, cmsgp); 236 msg.msg_controllen = (caddr_t)cmsgp - (caddr_t)msg.msg_control; 237 } 238 239 return (sendmsg(fd, &msg, flags)); 240} 241 242/* 243 * Find the first key for a packet to send. 244 * Try for a key that is eligible and has not expired, but settle for 245 * the last key if they have all expired. 246 * If no key is ready yet, give up. 247 */ 248struct auth * 249find_auth(struct interface *ifp) 250{ 251 struct auth *ap, *res = NULL; 252 int i; 253 254 255 if (ifp == NULL) 256 return (NULL); 257 258 if ((ap = ifp->int_auth) == NULL) 259 return (NULL); 260 261 for (i = 0; i < MAX_AUTH_KEYS; i++, ap++) { 262 /* stop looking after the last key */ 263 if (ap->type == RIP_AUTH_NONE) 264 break; 265 266 /* ignore keys that are not ready yet */ 267 if ((ulong_t)ap->start > (ulong_t)clk.tv_sec) 268 continue; 269 270 if ((ulong_t)ap->end < (ulong_t)clk.tv_sec) { 271 /* note best expired password as a fall-back */ 272 if (res == NULL || 273 (((ulong_t)ap->end > (ulong_t)res->end)) && 274 ((ulong_t)res->end < (ulong_t)clk.tv_sec)) 275 res = ap; 276 continue; 277 } 278 279 /* note key with the best future */ 280 if (res == NULL || (ulong_t)res->end < (ulong_t)ap->end) 281 res = ap; 282 } 283 return (res); 284} 285 286 287void 288clr_ws_buf(struct ws_buf *wb, struct auth *ap) 289{ 290 struct netauth *na; 291 292 wb->lim = wb->base + NETS_LEN; 293 wb->n = wb->base; 294 (void) memset(wb->n, 0, NETS_LEN*sizeof (*wb->n)); 295 296 /* 297 * (start to) install authentication if appropriate 298 */ 299 if (ap == NULL) 300 return; 301 302 na = (struct netauth *)wb->n; 303 if (ap->type == RIP_AUTH_PW) { 304 na->a_family = RIP_AF_AUTH; 305 na->a_type = RIP_AUTH_PW; 306 (void) memcpy(na->au.au_pw, ap->key, sizeof (na->au.au_pw)); 307 wb->n++; 308 309 } else if (ap->type == RIP_AUTH_MD5) { 310 na->a_family = RIP_AF_AUTH; 311 na->a_type = RIP_AUTH_MD5; 312 na->au.a_md5.md5_keyid = ap->keyid; 313 na->au.a_md5.md5_auth_len = RIP_AUTH_MD5_LEN; 314 na->au.a_md5.md5_seqno = htonl(clk.tv_sec); 315 wb->n++; 316 wb->lim--; /* make room for trailer */ 317 } 318} 319 320 321void 322end_md5_auth(struct ws_buf *wb, struct auth *ap) 323{ 324 struct netauth *na, *na2; 325 MD5_CTX md5_ctx; 326 int len; 327 328 na = (struct netauth *)wb->base; 329 na2 = (struct netauth *)wb->n; 330 len = (char *)na2-(char *)wb->buf; 331 na2->a_family = RIP_AF_AUTH; 332 na2->a_type = RIP_AUTH_TRAILER; 333 na->au.a_md5.md5_pkt_len = htons(len); 334 MD5Init(&md5_ctx); 335 /* len+4 to include auth trailer's family/type in MD5 sum */ 336 MD5Update(&md5_ctx, (uchar_t *)wb->buf, len + 4); 337 MD5Update(&md5_ctx, ap->key, RIP_AUTH_MD5_LEN); 338 MD5Final(na2->au.au_pw, &md5_ctx); 339 wb->n++; 340} 341 342 343/* 344 * Send the buffer 345 */ 346static void 347supply_write(struct ws_buf *wb) 348{ 349 /* 350 * Output multicast only if legal. 351 * If we would multicast and it would be illegal, then discard the 352 * packet. 353 */ 354 switch (wb->type) { 355 case NO_OUT_MULTICAST: 356 trace_pkt("skip multicast to %s because impossible", 357 naddr_ntoa(ws.to.sin_addr.s_addr)); 358 break; 359 case NO_OUT_RIPV2: 360 break; 361 default: 362 if (ws.a != NULL && ws.a->type == RIP_AUTH_MD5) 363 end_md5_auth(wb, ws.a); 364 if (output(wb->type, &ws.to, ws.ifp, wb->buf, 365 ((char *)wb->n - (char *)wb->buf)) < 0 && ws.ifp != NULL) 366 if_sick(ws.ifp, _B_FALSE); 367 ws.npackets++; 368 break; 369 } 370 371 clr_ws_buf(wb, ws.a); 372} 373 374 375/* 376 * Put an entry into the packet 377 */ 378static void 379supply_out(struct ag_info *ag) 380{ 381 uint32_t dstcount; 382 in_addr_t mask, v1_mask, dst_h, ddst_h = 0; 383 struct ws_buf *wb; 384 385 386 /* 387 * Skip this route if doing a flash update and it and the routes 388 * it aggregates have not changed recently. 389 */ 390 if (ag->ag_seqno < update_seqno && (ws.state & WS_ST_FLASH)) 391 return; 392 393 dst_h = ag->ag_dst_h; 394 mask = ag->ag_mask; 395 v1_mask = ripv1_mask_host(htonl(dst_h), 396 (ws.state & WS_ST_TO_ON_NET) ? ws.ifp : NULL); 397 dstcount = 0; 398 399 /* 400 * If we are sending RIPv2 packets that cannot (or must not) be 401 * heard by RIPv1 listeners, do not worry about sub- or supernets. 402 * Subnets (from other networks) can only be sent via multicast. 403 * A pair of subnet routes might have been promoted so that they 404 * are legal to send by RIPv1. 405 * If RIPv1 is off, use the multicast buffer. 406 */ 407 if ((ws.state & WS_ST_RIP2_ALL) || 408 ((ag->ag_state & AGS_RIPV2) && v1_mask != mask)) { 409 /* use the RIPv2-only buffer */ 410 wb = &v2buf; 411 412 } else { 413 /* 414 * use the RIPv1-or-RIPv2 buffer 415 */ 416 wb = &v12buf; 417 418 /* 419 * Convert supernet route into corresponding set of network 420 * routes for RIPv1, but leave non-contiguous netmasks 421 * to ag_check(). 422 */ 423 if (v1_mask > mask && 424 mask + (mask & -mask) == 0) { 425 ddst_h = v1_mask & -v1_mask; 426 dstcount = (v1_mask & ~mask)/ddst_h; 427 428 if (dstcount > ws.gen_limit) { 429 /* 430 * Punt if we would have to generate an 431 * unreasonable number of routes. 432 */ 433 if (TRACECONTENTS) 434 trace_misc("sending %s-->%s as 1" 435 " instead of %d routes", 436 addrname(htonl(dst_h), mask, 1), 437 naddr_ntoa(ws.to.sin_addr.s_addr), 438 dstcount + 1); 439 dstcount = 0; 440 441 } else { 442 mask = v1_mask; 443 ws.gen_limit -= dstcount; 444 } 445 } 446 } 447 448 do { 449 wb->n->n_family = RIP_AF_INET; 450 wb->n->n_dst = htonl(dst_h); 451 /* 452 * If the route is from router-discovery or we are 453 * shutting down, or this is a broken/sick interface, 454 * admit only a bad metric. 455 */ 456 wb->n->n_metric = ((stopint || ag->ag_metric < 1 || 457 (ag->ag_ifp && (ag->ag_ifp->int_state & 458 (IS_BROKE|IS_SICK)))) ? HOPCNT_INFINITY : ag->ag_metric); 459 wb->n->n_metric = htonl(wb->n->n_metric); 460 /* 461 * Any non-zero bits in the supposedly unused RIPv1 fields 462 * cause the old `routed` to ignore the route. 463 * That means the mask and so forth cannot be sent 464 * in the hybrid RIPv1/RIPv2 mode. 465 */ 466 if (ws.state & WS_ST_RIP2_ALL) { 467 if (ag->ag_nhop != 0 && 468 ((ws.state & WS_ST_QUERY) || 469 (ag->ag_nhop != ws.ifp->int_addr && 470 on_net(ag->ag_nhop, ws.ifp->int_net, 471 ws.ifp->int_mask)) && 472 ifwithaddr(ag->ag_nhop, _B_FALSE, _B_FALSE) == 473 NULL)) 474 wb->n->n_nhop = ag->ag_nhop; 475 wb->n->n_mask = htonl(mask); 476 wb->n->n_tag = ag->ag_tag; 477 } 478 dst_h += ddst_h; 479 480 if (++wb->n >= wb->lim) 481 supply_write(wb); 482 } while (dstcount-- > 0); 483} 484 485 486/* 487 * Supply one route from the table 488 */ 489/* ARGSUSED */ 490static int 491walk_supply(struct radix_node *rn, void *argp) 492{ 493#define RT ((struct rt_entry *)rn) 494 ushort_t ags; 495 uint8_t metric, pref; 496 in_addr_t dst, nhop; 497 struct rt_spare *rts; 498 uint_t sparecount; 499 500 501 /* 502 * Do not advertise external remote interfaces or passive interfaces. 503 */ 504 if ((RT->rt_state & RS_IF) && RT->rt_ifp != NULL && 505 (RT->rt_ifp->int_state & IS_PASSIVE) && 506 !(RT->rt_state & RS_MHOME)) 507 return (0); 508 /* 509 * Do not advertise routes learnt from /etc/gateways. 510 */ 511 if (RT->rt_spares[0].rts_origin == RO_FILE) 512 return (0); 513 514 /* 515 * Do not advertise routes which would lead to forwarding on a 516 * non-forwarding interface. 517 */ 518 if (RT->rt_state & RS_NOPROPAGATE) 519 return (0); 520 521 /* 522 * If being quiet about our ability to forward, then 523 * do not say anything unless responding to a query, 524 * except about our main interface. 525 */ 526 if (!should_supply(NULL) && !(ws.state & WS_ST_QUERY) && 527 !(RT->rt_state & RS_MHOME)) 528 return (0); 529 530 dst = RT->rt_dst; 531 532 /* 533 * do not collide with the fake default route 534 */ 535 if (dst == RIP_DEFAULT && (ws.state & WS_ST_DEFAULT)) 536 return (0); 537 538 if (RT->rt_state & RS_NET_SYN) { 539 if (RT->rt_state & RS_NET_INT) { 540 /* 541 * Do not send manual synthetic network routes 542 * into the subnet. 543 */ 544 if (on_net(ws.to.sin_addr.s_addr, 545 ntohl(dst), RT->rt_mask)) 546 return (0); 547 548 } else { 549 /* 550 * Do not send automatic synthetic network routes 551 * if they are not needed because no RIPv1 listeners 552 * can hear them. 553 */ 554 if (ws.state & WS_ST_RIP2_ALL) 555 return (0); 556 557 /* 558 * Do not send automatic synthetic network routes to 559 * the real subnet. 560 */ 561 if (on_net(ws.to.sin_addr.s_addr, 562 ntohl(dst), RT->rt_mask)) 563 return (0); 564 } 565 nhop = 0; 566 567 } else { 568 /* 569 * Advertise the next hop if this is not a route for one 570 * of our interfaces and the next hop is on the same 571 * network as the target. 572 * The final determination is made by supply_out(). 573 */ 574 if (!(RT->rt_state & RS_IF) && !(RT->rt_state & RS_MHOME) && 575 RT->rt_gate != loopaddr) 576 nhop = RT->rt_gate; 577 else 578 nhop = 0; 579 } 580 581 metric = RT->rt_metric; 582 ags = 0; 583 584 if (!RT_ISHOST(RT)) { 585 /* 586 * Always suppress network routes into other, existing 587 * network routes 588 */ 589 ags |= AGS_SUPPRESS; 590 591 /* 592 * Generate supernets if allowed. 593 * If we can be heard by RIPv1 systems, we will 594 * later convert back to ordinary nets. 595 * This unifies dealing with received supernets. 596 */ 597 if ((ws.state & WS_ST_AG) && ((RT->rt_state & RS_SUBNET) || 598 (ws.state & WS_ST_SUPER_AG))) 599 ags |= AGS_AGGREGATE; 600 } else if (!(RT->rt_state & RS_MHOME)) { 601 /* 602 * We should always suppress (into existing network routes) 603 * the host routes for the local end of our point-to-point 604 * links. 605 * If we are suppressing host routes in general, then do so. 606 * Avoid advertising host routes onto their own network, 607 * where they should be handled by proxy-ARP. 608 */ 609 if ((RT->rt_state & RS_LOCAL) || ridhosts || 610 on_net(dst, ws.to_net, ws.to_mask)) 611 ags |= AGS_SUPPRESS; 612 613 /* 614 * Aggregate stray host routes into network routes if allowed. 615 * We cannot aggregate host routes into small network routes 616 * without confusing RIPv1 listeners into thinking the 617 * network routes are host routes. 618 */ 619 if ((ws.state & WS_ST_AG) && (ws.state & WS_ST_RIP2_ALL)) 620 ags |= AGS_AGGREGATE; 621 } 622 623 /* 624 * Do not send RIPv1 advertisements of subnets to other 625 * networks. If possible, multicast them by RIPv2. 626 */ 627 if ((RT->rt_state & RS_SUBNET) && !(ws.state & WS_ST_RIP2_ALL) && 628 !on_net(dst, ws.to_std_net, ws.to_std_mask)) 629 ags |= AGS_RIPV2 | AGS_AGGREGATE; 630 631 632 /* 633 * Do not send a route back to where it came from, except in 634 * response to a query. This is "split-horizon". That means not 635 * advertising back to the same network and so via the same interface. 636 * 637 * We want to suppress routes that might have been fragmented 638 * from this route by a RIPv1 router and sent back to us, and so we 639 * cannot forget this route here. Let the split-horizon route 640 * suppress the fragmented routes and then itself be forgotten. 641 * 642 * Include the routes for both ends of point-to-point interfaces 643 * among those suppressed by split-horizon, since the other side 644 * should knows them as well as we do. 645 * 646 * Notice spare routes with the same metric that we are about to 647 * advertise, to split the horizon on redundant, inactive paths. 648 */ 649 if (ws.ifp != NULL && !(ws.state & WS_ST_QUERY) && 650 (ws.state & WS_ST_TO_ON_NET) && (!(RT->rt_state & RS_IF) || 651 (ws.ifp->int_if_flags & IFF_POINTOPOINT))) { 652 for (rts = RT->rt_spares, sparecount = 0; 653 sparecount < RT->rt_num_spares; sparecount++, rts++) { 654 if (rts->rts_metric > metric || rts->rts_ifp != ws.ifp) 655 continue; 656 657 /* 658 * If we do not mark the route with AGS_SPLIT_HZ here, 659 * it will be poisoned-reverse, or advertised back 660 * toward its source with an infinite metric. 661 * If we have recently advertised the route with a 662 * better metric than we now have, then we should 663 * poison-reverse the route before suppressing it for 664 * split-horizon. 665 * 666 * In almost all cases, if there is no spare for the 667 * route then it is either old and dead or a brand 668 * new route. If it is brand new, there is no need 669 * for poison-reverse. If it is old and dead, it 670 * is already poisoned. 671 */ 672 if (RT->rt_poison_time < now_expire || 673 RT->rt_poison_metric >= metric || 674 RT->rt_spares[1].rts_gate == 0) { 675 ags |= AGS_SPLIT_HZ; 676 ags &= ~AGS_SUPPRESS; 677 } 678 metric = HOPCNT_INFINITY; 679 break; 680 } 681 } 682 683 /* 684 * Keep track of the best metric with which the 685 * route has been advertised recently. 686 */ 687 if (RT->rt_poison_metric >= metric || 688 RT->rt_poison_time < now_expire) { 689 RT->rt_poison_time = now.tv_sec; 690 RT->rt_poison_metric = metric; 691 } 692 693 /* 694 * Adjust the outgoing metric by the cost of the link. 695 * Avoid aggregation when a route is counting to infinity. 696 */ 697 pref = RT->rt_poison_metric + ws.metric; 698 metric += ws.metric; 699 700 /* 701 * If this is a static route pointing to the same interface 702 * upon which we are sending out the RIP RESPONSE 703 * adjust the preference so that we don't aggregate into this 704 * route. Note that the maximum possible hop count on a route 705 * per RFC 2453 is 16 (HOPCNT_INFINITY) 706 */ 707 if ((RT->rt_state & RS_STATIC) && (ws.ifp == RT->rt_ifp)) 708 pref = (HOPCNT_INFINITY+1); 709 710 /* 711 * Do not advertise stable routes that will be ignored, 712 * unless we are answering a query. 713 * If the route recently was advertised with a metric that 714 * would have been less than infinity through this interface, 715 * we need to continue to advertise it in order to poison it. 716 */ 717 if (metric >= HOPCNT_INFINITY) { 718 if (!(ws.state & WS_ST_QUERY) && (pref >= HOPCNT_INFINITY || 719 RT->rt_poison_time < now_garbage)) 720 return (0); 721 722 metric = HOPCNT_INFINITY; 723 } 724 725 /* 726 * supply this route out on the wire- we only care about dest/mask 727 * and so can ignore all rt_spares[i] with i > 0 728 */ 729 ag_check(dst, RT->rt_mask, 0, RT->rt_ifp, nhop, metric, pref, 730 RT->rt_seqno, RT->rt_tag, ags, supply_out); 731 return (0); 732#undef RT 733} 734 735 736/* 737 * Supply dst with the contents of the routing tables. 738 * If this won't fit in one packet, chop it up into several. 739 */ 740void 741supply(struct sockaddr_in *dst, 742 struct interface *ifp, /* output interface */ 743 enum output_type type, 744 int flash, /* 1=flash update */ 745 int vers, /* RIP version */ 746 boolean_t passwd_ok) /* OK to include cleartext password */ 747{ 748 struct rt_entry *rt; 749 uint8_t def_metric; 750 751 752 ws.state = 0; 753 ws.gen_limit = WS_GEN_LIMIT_MAX; 754 755 ws.to = *dst; 756 ws.to_std_mask = std_mask(ws.to.sin_addr.s_addr); 757 ws.to_std_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_std_mask; 758 759 if (ifp != NULL) { 760 ws.to_mask = ifp->int_mask; 761 ws.to_net = ifp->int_net; 762 if (on_net(ws.to.sin_addr.s_addr, ws.to_net, ws.to_mask) || 763 type == OUT_MULTICAST) 764 ws.state |= WS_ST_TO_ON_NET; 765 766 } else { 767 ws.to_mask = ripv1_mask_net(ws.to.sin_addr.s_addr, NULL); 768 ws.to_net = ntohl(ws.to.sin_addr.s_addr) & ws.to_mask; 769 rt = rtfind(dst->sin_addr.s_addr); 770 if (rt != NULL) 771 ifp = rt->rt_ifp; 772 else 773 return; 774 } 775 776 ws.npackets = 0; 777 if (flash) 778 ws.state |= WS_ST_FLASH; 779 780 ws.ifp = ifp; 781 782 /* 783 * Routes in the table were already adjusted by their respective 784 * destination interface costs (which are zero by default) on 785 * input. The following is the value by which each route's metric 786 * will be bumped up on output. 787 */ 788 ws.metric = 1; 789 790 ripv12_buf.rip.rip_vers = vers; 791 792 switch (type) { 793 case OUT_MULTICAST: 794 if (ifp->int_if_flags & IFF_MULTICAST) 795 v2buf.type = OUT_MULTICAST; 796 else 797 v2buf.type = NO_OUT_MULTICAST; 798 v12buf.type = OUT_BROADCAST; 799 break; 800 801 case OUT_QUERY: 802 ws.state |= WS_ST_QUERY; 803 /* FALLTHROUGH */ 804 case OUT_BROADCAST: 805 case OUT_UNICAST: 806 v2buf.type = (vers == RIPv2) ? type : NO_OUT_RIPV2; 807 v12buf.type = type; 808 break; 809 810 case NO_OUT_MULTICAST: 811 case NO_OUT_RIPV2: 812 return; /* no output */ 813 } 814 815 if (vers == RIPv2) { 816 /* full RIPv2 only if cannot be heard by RIPv1 listeners */ 817 if (type != OUT_BROADCAST) 818 ws.state |= WS_ST_RIP2_ALL; 819 if ((ws.state & WS_ST_QUERY) || !(ws.state & WS_ST_TO_ON_NET)) { 820 ws.state |= (WS_ST_AG | WS_ST_SUPER_AG); 821 } else if (ifp == NULL || !(ifp->int_state & IS_NO_AG)) { 822 ws.state |= WS_ST_AG; 823 if (type != OUT_BROADCAST && (ifp == NULL || 824 !(ifp->int_state & IS_NO_SUPER_AG))) 825 ws.state |= WS_ST_SUPER_AG; 826 } 827 828 /* See if this packet needs authenticating */ 829 ws.a = find_auth(ifp); 830 if (!passwd_ok && ws.a != NULL && ws.a->type == RIP_AUTH_PW) 831 ws.a = NULL; 832 if (ws.a != NULL && (ulong_t)ws.a->end < (ulong_t)clk.tv_sec && 833 !ws.a->warnedflag) { 834 /* 835 * If the best key is an expired one, we may as 836 * well use it. Log this event. 837 */ 838 writelog(LOG_WARNING, 839 "Using expired auth while transmitting to %s", 840 naddr_ntoa(ws.to.sin_addr.s_addr)); 841 ws.a->warnedflag = 1; 842 } 843 } else { 844 ws.a = NULL; 845 } 846 847 clr_ws_buf(&v12buf, ws.a); 848 clr_ws_buf(&v2buf, ws.a); 849 850 /* 851 * Fake a default route if asked and if there is not already 852 * a better, real default route. 853 */ 854 if (should_supply(NULL) && (def_metric = ifp->int_d_metric) != 0) { 855 if (NULL == (rt = rtget(RIP_DEFAULT, 0)) || 856 rt->rt_metric+ws.metric >= def_metric) { 857 ws.state |= WS_ST_DEFAULT; 858 ag_check(0, 0, 0, NULL, 0, def_metric, def_metric, 859 0, 0, 0, supply_out); 860 } else { 861 def_metric = rt->rt_metric+ws.metric; 862 } 863 864 /* 865 * If both RIPv2 and the poor-man's router discovery 866 * kludge are on, arrange to advertise an extra 867 * default route via RIPv1. 868 */ 869 if ((ws.state & WS_ST_RIP2_ALL) && 870 (ifp->int_state & IS_PM_RDISC)) { 871 ripv12_buf.rip.rip_vers = RIPv1; 872 v12buf.n->n_family = RIP_AF_INET; 873 v12buf.n->n_dst = htonl(RIP_DEFAULT); 874 v12buf.n->n_metric = htonl(def_metric); 875 v12buf.n++; 876 } 877 } 878 879 (void) rn_walktree(rhead, walk_supply, NULL); 880 ag_flush(0, 0, supply_out); 881 882 /* 883 * Flush the packet buffers, provided they are not empty and 884 * do not contain only the password. 885 */ 886 if (v12buf.n != v12buf.base && 887 (v12buf.n > v12buf.base+1 || 888 v12buf.base->n_family != RIP_AF_AUTH)) 889 supply_write(&v12buf); 890 if (v2buf.n != v2buf.base && (v2buf.n > v2buf.base+1 || 891 v2buf.base->n_family != RIP_AF_AUTH)) 892 supply_write(&v2buf); 893 894 /* 895 * If we sent nothing and this is an answer to a query, send 896 * an empty buffer. 897 */ 898 if (ws.npackets == 0 && (ws.state & WS_ST_QUERY)) { 899 supply_write(&v2buf); 900 if (ws.npackets == 0) 901 supply_write(&v12buf); 902 } 903} 904 905 906/* 907 * send all of the routing table or just do a flash update 908 */ 909void 910rip_bcast(int flash) 911{ 912 static struct sockaddr_in dst = {AF_INET}; 913 struct interface *ifp; 914 enum output_type type; 915 int vers; 916 struct timeval rtime; 917 918 919 need_flash = _B_FALSE; 920 intvl_random(&rtime, MIN_WAITTIME, MAX_WAITTIME); 921 no_flash = rtime; 922 timevaladd(&no_flash, &now); 923 924 if (!rip_enabled) 925 return; 926 927 trace_act("send %s and inhibit dynamic updates for %.3f sec", 928 flash ? "dynamic update" : "all routes", 929 rtime.tv_sec + ((double)rtime.tv_usec)/1000000.0); 930 931 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) { 932 /* 933 * Skip interfaces not doing RIP or for which IP 934 * forwarding isn't turned on. Skip duplicate 935 * interfaces, we don't want to generate duplicate 936 * packets. Do try broken interfaces to see if they 937 * have healed. 938 */ 939 if (IS_RIP_OUT_OFF(ifp->int_state) || 940 (ifp->int_state & IS_DUP) || 941 !IS_IFF_ROUTING(ifp->int_if_flags)) 942 continue; 943 944 /* skip turned off interfaces */ 945 if (!IS_IFF_UP(ifp->int_if_flags)) 946 continue; 947 948 /* skip interfaces we shouldn't use */ 949 if (IS_IFF_QUIET(ifp->int_if_flags)) 950 continue; 951 952 vers = (ifp->int_state & IS_NO_RIPV1_OUT) ? RIPv2 : RIPv1; 953 dst.sin_addr.s_addr = ifp->int_ripout_addr; 954 955 /* 956 * Ignore the interface if it's not broadcast, 957 * point-to-point, or remote. It must be non-broadcast 958 * multiaccess, and therefore unsupported. 959 */ 960 if (!(ifp->int_if_flags & (IFF_BROADCAST | IFF_POINTOPOINT)) && 961 !(ifp->int_state & IS_REMOTE)) 962 continue; 963 964 type = (ifp->int_if_flags & IFF_BROADCAST) ? 965 OUT_BROADCAST : OUT_UNICAST; 966 if (vers == RIPv2 && (ifp->int_if_flags & IFF_MULTICAST) && 967 !(ifp->int_state & IS_NO_RIP_MCAST)) 968 type = OUT_MULTICAST; 969 970 supply(&dst, ifp, type, flash, vers, _B_TRUE); 971 } 972 973 update_seqno++; /* all routes are up to date */ 974} 975 976 977/* 978 * Ask for routes 979 * Do it only once to an interface, and not even after the interface 980 * was broken and recovered. 981 */ 982void 983rip_query(void) 984{ 985 static struct sockaddr_in dst = {AF_INET}; 986 struct interface *ifp; 987 struct rip buf; 988 enum output_type type; 989 990 991 if (!rip_enabled) 992 return; 993 994 (void) memset(&buf, 0, sizeof (buf)); 995 996 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 997 /* 998 * Skip interfaces those already queried. Do not ask 999 * via interfaces through which we don't accept input. 1000 * Do not ask via interfaces that cannot send RIP 1001 * packets. Don't send queries on duplicate 1002 * interfaces, that would generate duplicate packets 1003 * on link. Do try broken interfaces to see if they 1004 * have healed. 1005 */ 1006 if (IS_RIP_IN_OFF(ifp->int_state) || 1007 (ifp->int_state & IS_DUP) || 1008 ifp->int_query_time != NEVER) 1009 continue; 1010 1011 /* skip turned off interfaces */ 1012 if (!IS_IFF_UP(ifp->int_if_flags)) 1013 continue; 1014 1015 /* skip interfaces we shouldn't use */ 1016 if (IS_IFF_QUIET(ifp->int_if_flags)) 1017 continue; 1018 1019 /* 1020 * Ignore the interface if it's not broadcast, 1021 * point-to-point, or remote. It must be non-broadcast 1022 * multiaccess, and therefore unsupported. 1023 */ 1024 if (!(ifp->int_if_flags & (IFF_BROADCAST | IFF_POINTOPOINT)) && 1025 !(ifp->int_state & IS_REMOTE)) 1026 continue; 1027 1028 buf.rip_cmd = RIPCMD_REQUEST; 1029 buf.rip_nets[0].n_family = RIP_AF_UNSPEC; 1030 buf.rip_nets[0].n_metric = htonl(HOPCNT_INFINITY); 1031 1032 /* 1033 * Send a RIPv1 query only if allowed and if we will 1034 * listen to RIPv1 routers. 1035 */ 1036 if ((ifp->int_state & IS_NO_RIPV1_OUT) || 1037 (ifp->int_state & IS_NO_RIPV1_IN)) { 1038 buf.rip_vers = RIPv2; 1039 } else { 1040 buf.rip_vers = RIPv1; 1041 } 1042 1043 dst.sin_addr.s_addr = ifp->int_ripout_addr; 1044 1045 type = (ifp->int_if_flags & IFF_BROADCAST) ? 1046 OUT_BROADCAST : OUT_UNICAST; 1047 if (buf.rip_vers == RIPv2 && 1048 (ifp->int_if_flags & IFF_MULTICAST) && 1049 !(ifp->int_state & IS_NO_RIP_MCAST)) 1050 type = OUT_MULTICAST; 1051 1052 ifp->int_query_time = now.tv_sec+SUPPLY_INTERVAL; 1053 if (output(type, &dst, ifp, &buf, sizeof (buf)) < 0) 1054 if_sick(ifp, _B_FALSE); 1055 } 1056} 1057