table.c revision 126250
155505Sshin/* 255505Sshin * Copyright (c) 1983, 1988, 1993 355505Sshin * The Regents of the University of California. All rights reserved. 455505Sshin * 555505Sshin * Redistribution and use in source and binary forms, with or without 655505Sshin * modification, are permitted provided that the following conditions 755505Sshin * are met: 855505Sshin * 1. Redistributions of source code must retain the above copyright 955505Sshin * notice, this list of conditions and the following disclaimer. 1055505Sshin * 2. Redistributions in binary form must reproduce the above copyright 1155505Sshin * notice, this list of conditions and the following disclaimer in the 1255505Sshin * documentation and/or other materials provided with the distribution. 1355505Sshin * 3. All advertising materials mentioning features or use of this software 1455505Sshin * must display the following acknowledgment: 1555505Sshin * This product includes software developed by the University of 1655505Sshin * California, Berkeley and its contributors. 1755505Sshin * 4. Neither the name of the University nor the names of its contributors 1855505Sshin * may be used to endorse or promote products derived from this software 1955505Sshin * without specific prior written permission. 2055505Sshin * 2155505Sshin * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 2255505Sshin * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 2355505Sshin * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 2455505Sshin * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 2555505Sshin * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2655505Sshin * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27122107Sume * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2855505Sshin * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2955505Sshin * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30156837Sru * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31156837Sru * SUCH DAMAGE. 32156813Sru * 33156813Sru * $FreeBSD: head/sbin/routed/table.c 126250 2004-02-25 23:45:57Z bms $ 3455505Sshin */ 35195767Skensmith 3669640Sobrien#include "defs.h" 3759266Ssteve 38156813Sru#ifdef __NetBSD__ 3959266Ssteve__RCSID("$NetBSD$"); 4059266Ssteve#elif defined(__FreeBSD__) 4155505Sshin__RCSID("$FreeBSD: head/sbin/routed/table.c 126250 2004-02-25 23:45:57Z bms $"); 42171135Sgnn#else 4362583Sitojun__RCSID("$Revision: 2.27 $"); 4455505Sshin#ident "$Revision: 2.27 $" 4555505Sshin#endif 4662583Sitojun#ident "$FreeBSD: head/sbin/routed/table.c 126250 2004-02-25 23:45:57Z bms $" 4755505Sshin 4858906Sshinstatic struct rt_spare *rts_better(struct rt_entry *); 4958906Sshinstatic struct rt_spare rts_empty = {0,0,0,HOPCNT_INFINITY,0,0,0}; 5055505Sshinstatic void set_need_flash(void); 51201381Sed#ifdef _HAVE_SIN_LEN 52201381Sedstatic void masktrim(struct sockaddr_in *ap); 5374870Sru#else 5455505Sshinstatic void masktrim(struct sockaddr_in_new *ap); 5555505Sshin#endif 5655505Sshin 5755505Sshin 5855505Sshinstruct radix_node_head *rhead; /* root of the radix tree */ 5955505Sshin 6055505Sshinint need_flash = 1; /* flash update needed 61 * start =1 to suppress the 1st 62 */ 63 64struct timeval age_timer; /* next check of old routes */ 65struct timeval need_kern = { /* need to update kernel table */ 66 EPOCH+MIN_WAITTIME-1, 0 67}; 68 69int stopint; 70 71int total_routes; 72 73/* zap any old routes through this gateway */ 74naddr age_bad_gate; 75 76 77/* It is desirable to "aggregate" routes, to combine differing routes of 78 * the same metric and next hop into a common route with a smaller netmask 79 * or to suppress redundant routes, routes that add no information to 80 * routes with smaller netmasks. 81 * 82 * A route is redundant if and only if any and all routes with smaller 83 * but matching netmasks and nets are the same. Since routes are 84 * kept sorted in the radix tree, redundant routes always come second. 85 * 86 * There are two kinds of aggregations. First, two routes of the same bit 87 * mask and differing only in the least significant bit of the network 88 * number can be combined into a single route with a coarser mask. 89 * 90 * Second, a route can be suppressed in favor of another route with a more 91 * coarse mask provided no incompatible routes with intermediate masks 92 * are present. The second kind of aggregation involves suppressing routes. 93 * A route must not be suppressed if an incompatible route exists with 94 * an intermediate mask, since the suppressed route would be covered 95 * by the intermediate. 96 * 97 * This code relies on the radix tree walk encountering routes 98 * sorted first by address, with the smallest address first. 99 */ 100 101struct ag_info ag_slots[NUM_AG_SLOTS], *ag_avail, *ag_corsest, *ag_finest; 102 103/* #define DEBUG_AG */ 104#ifdef DEBUG_AG 105#define CHECK_AG() {int acnt = 0; struct ag_info *cag; \ 106 for (cag = ag_avail; cag != 0; cag = cag->ag_fine) \ 107 acnt++; \ 108 for (cag = ag_corsest; cag != 0; cag = cag->ag_fine) \ 109 acnt++; \ 110 if (acnt != NUM_AG_SLOTS) { \ 111 (void)fflush(stderr); \ 112 abort(); \ 113 } \ 114} 115#else 116#define CHECK_AG() 117#endif 118 119 120/* Output the contents of an aggregation table slot. 121 * This function must always be immediately followed with the deletion 122 * of the target slot. 123 */ 124static void 125ag_out(struct ag_info *ag, 126 void (*out)(struct ag_info *)) 127{ 128 struct ag_info *ag_cors; 129 naddr bit; 130 131 132 /* Forget it if this route should not be output for split-horizon. */ 133 if (ag->ag_state & AGS_SPLIT_HZ) 134 return; 135 136 /* If we output both the even and odd twins, then the immediate parent, 137 * if it is present, is redundant, unless the parent manages to 138 * aggregate into something coarser. 139 * On successive calls, this code detects the even and odd twins, 140 * and marks the parent. 141 * 142 * Note that the order in which the radix tree code emits routes 143 * ensures that the twins are seen before the parent is emitted. 144 */ 145 ag_cors = ag->ag_cors; 146 if (ag_cors != 0 147 && ag_cors->ag_mask == ag->ag_mask<<1 148 && ag_cors->ag_dst_h == (ag->ag_dst_h & ag_cors->ag_mask)) { 149 ag_cors->ag_state |= ((ag_cors->ag_dst_h == ag->ag_dst_h) 150 ? AGS_REDUN0 151 : AGS_REDUN1); 152 } 153 154 /* Skip it if this route is itself redundant. 155 * 156 * It is ok to change the contents of the slot here, since it is 157 * always deleted next. 158 */ 159 if (ag->ag_state & AGS_REDUN0) { 160 if (ag->ag_state & AGS_REDUN1) 161 return; /* quit if fully redundant */ 162 /* make it finer if it is half-redundant */ 163 bit = (-ag->ag_mask) >> 1; 164 ag->ag_dst_h |= bit; 165 ag->ag_mask |= bit; 166 167 } else if (ag->ag_state & AGS_REDUN1) { 168 /* make it finer if it is half-redundant */ 169 bit = (-ag->ag_mask) >> 1; 170 ag->ag_mask |= bit; 171 } 172 out(ag); 173} 174 175 176static void 177ag_del(struct ag_info *ag) 178{ 179 CHECK_AG(); 180 181 if (ag->ag_cors == 0) 182 ag_corsest = ag->ag_fine; 183 else 184 ag->ag_cors->ag_fine = ag->ag_fine; 185 186 if (ag->ag_fine == 0) 187 ag_finest = ag->ag_cors; 188 else 189 ag->ag_fine->ag_cors = ag->ag_cors; 190 191 ag->ag_fine = ag_avail; 192 ag_avail = ag; 193 194 CHECK_AG(); 195} 196 197 198/* Flush routes waiting for aggregation. 199 * This must not suppress a route unless it is known that among all 200 * routes with coarser masks that match it, the one with the longest 201 * mask is appropriate. This is ensured by scanning the routes 202 * in lexical order, and with the most restrictive mask first 203 * among routes to the same destination. 204 */ 205void 206ag_flush(naddr lim_dst_h, /* flush routes to here */ 207 naddr lim_mask, /* matching this mask */ 208 void (*out)(struct ag_info *)) 209{ 210 struct ag_info *ag, *ag_cors; 211 naddr dst_h; 212 213 214 for (ag = ag_finest; 215 ag != 0 && ag->ag_mask >= lim_mask; 216 ag = ag_cors) { 217 ag_cors = ag->ag_cors; 218 219 /* work on only the specified routes */ 220 dst_h = ag->ag_dst_h; 221 if ((dst_h & lim_mask) != lim_dst_h) 222 continue; 223 224 if (!(ag->ag_state & AGS_SUPPRESS)) 225 ag_out(ag, out); 226 227 else for ( ; ; ag_cors = ag_cors->ag_cors) { 228 /* Look for a route that can suppress the 229 * current route */ 230 if (ag_cors == 0) { 231 /* failed, so output it and look for 232 * another route to work on 233 */ 234 ag_out(ag, out); 235 break; 236 } 237 238 if ((dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h) { 239 /* We found a route with a coarser mask that 240 * aggregates the current target. 241 * 242 * If it has a different next hop, it 243 * cannot replace the target, so output 244 * the target. 245 */ 246 if (ag->ag_gate != ag_cors->ag_gate 247 && !(ag->ag_state & AGS_FINE_GATE) 248 && !(ag_cors->ag_state & AGS_CORS_GATE)) { 249 ag_out(ag, out); 250 break; 251 } 252 253 /* If the coarse route has a good enough 254 * metric, it suppresses the target. 255 * If the suppressed target was redundant, 256 * then mark the suppressor redundant. 257 */ 258 if (ag_cors->ag_pref <= ag->ag_pref) { 259 if (AG_IS_REDUN(ag->ag_state) 260 && ag_cors->ag_mask==ag->ag_mask<<1) { 261 if (ag_cors->ag_dst_h == dst_h) 262 ag_cors->ag_state |= AGS_REDUN0; 263 else 264 ag_cors->ag_state |= AGS_REDUN1; 265 } 266 if (ag->ag_tag != ag_cors->ag_tag) 267 ag_cors->ag_tag = 0; 268 if (ag->ag_nhop != ag_cors->ag_nhop) 269 ag_cors->ag_nhop = 0; 270 break; 271 } 272 } 273 } 274 275 /* That route has either been output or suppressed */ 276 ag_cors = ag->ag_cors; 277 ag_del(ag); 278 } 279 280 CHECK_AG(); 281} 282 283 284/* Try to aggregate a route with previous routes. 285 */ 286void 287ag_check(naddr dst, 288 naddr mask, 289 naddr gate, 290 naddr nhop, 291 char metric, 292 char pref, 293 u_int new_seqno, 294 u_short tag, 295 u_short state, 296 void (*out)(struct ag_info *)) /* output using this */ 297{ 298 struct ag_info *ag, *nag, *ag_cors; 299 naddr xaddr; 300 int x; 301 302 dst = ntohl(dst); 303 304 /* Punt non-contiguous subnet masks. 305 * 306 * (X & -X) contains a single bit if and only if X is a power of 2. 307 * (X + (X & -X)) == 0 if and only if X is a power of 2. 308 */ 309 if ((mask & -mask) + mask != 0) { 310 struct ag_info nc_ag; 311 312 nc_ag.ag_dst_h = dst; 313 nc_ag.ag_mask = mask; 314 nc_ag.ag_gate = gate; 315 nc_ag.ag_nhop = nhop; 316 nc_ag.ag_metric = metric; 317 nc_ag.ag_pref = pref; 318 nc_ag.ag_tag = tag; 319 nc_ag.ag_state = state; 320 nc_ag.ag_seqno = new_seqno; 321 out(&nc_ag); 322 return; 323 } 324 325 /* Search for the right slot in the aggregation table. 326 */ 327 ag_cors = 0; 328 ag = ag_corsest; 329 while (ag != 0) { 330 if (ag->ag_mask >= mask) 331 break; 332 333 /* Suppress old routes (i.e. combine with compatible routes 334 * with coarser masks) as we look for the right slot in the 335 * aggregation table for the new route. 336 * A route to an address less than the current destination 337 * will not be affected by the current route or any route 338 * seen hereafter. That means it is safe to suppress it. 339 * This check keeps poor routes (e.g. with large hop counts) 340 * from preventing suppression of finer routes. 341 */ 342 if (ag_cors != 0 343 && ag->ag_dst_h < dst 344 && (ag->ag_state & AGS_SUPPRESS) 345 && ag_cors->ag_pref <= ag->ag_pref 346 && (ag->ag_dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h 347 && (ag_cors->ag_gate == ag->ag_gate 348 || (ag->ag_state & AGS_FINE_GATE) 349 || (ag_cors->ag_state & AGS_CORS_GATE))) { 350 /* If the suppressed target was redundant, 351 * then mark the suppressor redundant. 352 */ 353 if (AG_IS_REDUN(ag->ag_state) 354 && ag_cors->ag_mask == ag->ag_mask<<1) { 355 if (ag_cors->ag_dst_h == dst) 356 ag_cors->ag_state |= AGS_REDUN0; 357 else 358 ag_cors->ag_state |= AGS_REDUN1; 359 } 360 if (ag->ag_tag != ag_cors->ag_tag) 361 ag_cors->ag_tag = 0; 362 if (ag->ag_nhop != ag_cors->ag_nhop) 363 ag_cors->ag_nhop = 0; 364 ag_del(ag); 365 CHECK_AG(); 366 } else { 367 ag_cors = ag; 368 } 369 ag = ag_cors->ag_fine; 370 } 371 372 /* If we find the even/odd twin of the new route, and if the 373 * masks and so forth are equal, we can aggregate them. 374 * We can probably promote one of the pair. 375 * 376 * Since the routes are encountered in lexical order, 377 * the new route must be odd. However, the second or later 378 * times around this loop, it could be the even twin promoted 379 * from the even/odd pair of twins of the finer route. 380 */ 381 while (ag != 0 382 && ag->ag_mask == mask 383 && ((ag->ag_dst_h ^ dst) & (mask<<1)) == 0) { 384 385 /* Here we know the target route and the route in the current 386 * slot have the same netmasks and differ by at most the 387 * last bit. They are either for the same destination, or 388 * for an even/odd pair of destinations. 389 */ 390 if (ag->ag_dst_h == dst) { 391 /* We have two routes to the same destination. 392 * Routes are encountered in lexical order, so a 393 * route is never promoted until the parent route is 394 * already present. So we know that the new route is 395 * a promoted (or aggregated) pair and the route 396 * already in the slot is the explicit route. 397 * 398 * Prefer the best route if their metrics differ, 399 * or the aggregated one if not, following a sort 400 * of longest-match rule. 401 */ 402 if (pref <= ag->ag_pref) { 403 ag->ag_gate = gate; 404 ag->ag_nhop = nhop; 405 ag->ag_tag = tag; 406 ag->ag_metric = metric; 407 ag->ag_pref = pref; 408 if (ag->ag_seqno < new_seqno) 409 ag->ag_seqno = new_seqno; 410 x = ag->ag_state; 411 ag->ag_state = state; 412 state = x; 413 } 414 415 /* Some bits are set if they are set on either route, 416 * except when the route is for an interface. 417 */ 418 if (!(ag->ag_state & AGS_IF)) 419 ag->ag_state |= (state & (AGS_AGGREGATE_EITHER 420 | AGS_REDUN0 421 | AGS_REDUN1)); 422 return; 423 } 424 425 /* If one of the routes can be promoted and the other can 426 * be suppressed, it may be possible to combine them or 427 * worthwhile to promote one. 428 * 429 * Any route that can be promoted is always 430 * marked to be eligible to be suppressed. 431 */ 432 if (!((state & AGS_AGGREGATE) 433 && (ag->ag_state & AGS_SUPPRESS)) 434 && !((ag->ag_state & AGS_AGGREGATE) 435 && (state & AGS_SUPPRESS))) 436 break; 437 438 /* A pair of even/odd twin routes can be combined 439 * if either is redundant, or if they are via the 440 * same gateway and have the same metric. 441 */ 442 if (AG_IS_REDUN(ag->ag_state) 443 || AG_IS_REDUN(state) 444 || (ag->ag_gate == gate 445 && ag->ag_pref == pref 446 && (state & ag->ag_state & AGS_AGGREGATE) != 0)) { 447 448 /* We have both the even and odd pairs. 449 * Since the routes are encountered in order, 450 * the route in the slot must be the even twin. 451 * 452 * Combine and promote (aggregate) the pair of routes. 453 */ 454 if (new_seqno < ag->ag_seqno) 455 new_seqno = ag->ag_seqno; 456 if (!AG_IS_REDUN(state)) 457 state &= ~AGS_REDUN1; 458 if (AG_IS_REDUN(ag->ag_state)) 459 state |= AGS_REDUN0; 460 else 461 state &= ~AGS_REDUN0; 462 state |= (ag->ag_state & AGS_AGGREGATE_EITHER); 463 if (ag->ag_tag != tag) 464 tag = 0; 465 if (ag->ag_nhop != nhop) 466 nhop = 0; 467 468 /* Get rid of the even twin that was already 469 * in the slot. 470 */ 471 ag_del(ag); 472 473 } else if (ag->ag_pref >= pref 474 && (ag->ag_state & AGS_AGGREGATE)) { 475 /* If we cannot combine the pair, maybe the route 476 * with the worse metric can be promoted. 477 * 478 * Promote the old, even twin, by giving its slot 479 * in the table to the new, odd twin. 480 */ 481 ag->ag_dst_h = dst; 482 483 xaddr = ag->ag_gate; 484 ag->ag_gate = gate; 485 gate = xaddr; 486 487 xaddr = ag->ag_nhop; 488 ag->ag_nhop = nhop; 489 nhop = xaddr; 490 491 x = ag->ag_tag; 492 ag->ag_tag = tag; 493 tag = x; 494 495 /* The promoted route is even-redundant only if the 496 * even twin was fully redundant. It is not 497 * odd-redundant because the odd-twin will still be 498 * in the table. 499 */ 500 x = ag->ag_state; 501 if (!AG_IS_REDUN(x)) 502 x &= ~AGS_REDUN0; 503 x &= ~AGS_REDUN1; 504 ag->ag_state = state; 505 state = x; 506 507 x = ag->ag_metric; 508 ag->ag_metric = metric; 509 metric = x; 510 511 x = ag->ag_pref; 512 ag->ag_pref = pref; 513 pref = x; 514 515 /* take the newest sequence number */ 516 if (new_seqno <= ag->ag_seqno) 517 new_seqno = ag->ag_seqno; 518 else 519 ag->ag_seqno = new_seqno; 520 521 } else { 522 if (!(state & AGS_AGGREGATE)) 523 break; /* cannot promote either twin */ 524 525 /* Promote the new, odd twin by shaving its 526 * mask and address. 527 * The promoted route is odd-redundant only if the 528 * odd twin was fully redundant. It is not 529 * even-redundant because the even twin is still in 530 * the table. 531 */ 532 if (!AG_IS_REDUN(state)) 533 state &= ~AGS_REDUN1; 534 state &= ~AGS_REDUN0; 535 if (new_seqno < ag->ag_seqno) 536 new_seqno = ag->ag_seqno; 537 else 538 ag->ag_seqno = new_seqno; 539 } 540 541 mask <<= 1; 542 dst &= mask; 543 544 if (ag_cors == 0) { 545 ag = ag_corsest; 546 break; 547 } 548 ag = ag_cors; 549 ag_cors = ag->ag_cors; 550 } 551 552 /* When we can no longer promote and combine routes, 553 * flush the old route in the target slot. Also flush 554 * any finer routes that we know will never be aggregated by 555 * the new route. 556 * 557 * In case we moved toward coarser masks, 558 * get back where we belong 559 */ 560 if (ag != 0 561 && ag->ag_mask < mask) { 562 ag_cors = ag; 563 ag = ag->ag_fine; 564 } 565 566 /* Empty the target slot 567 */ 568 if (ag != 0 && ag->ag_mask == mask) { 569 ag_flush(ag->ag_dst_h, ag->ag_mask, out); 570 ag = (ag_cors == 0) ? ag_corsest : ag_cors->ag_fine; 571 } 572 573#ifdef DEBUG_AG 574 (void)fflush(stderr); 575 if (ag == 0 && ag_cors != ag_finest) 576 abort(); 577 if (ag_cors == 0 && ag != ag_corsest) 578 abort(); 579 if (ag != 0 && ag->ag_cors != ag_cors) 580 abort(); 581 if (ag_cors != 0 && ag_cors->ag_fine != ag) 582 abort(); 583 CHECK_AG(); 584#endif 585 586 /* Save the new route on the end of the table. 587 */ 588 nag = ag_avail; 589 ag_avail = nag->ag_fine; 590 591 nag->ag_dst_h = dst; 592 nag->ag_mask = mask; 593 nag->ag_gate = gate; 594 nag->ag_nhop = nhop; 595 nag->ag_metric = metric; 596 nag->ag_pref = pref; 597 nag->ag_tag = tag; 598 nag->ag_state = state; 599 nag->ag_seqno = new_seqno; 600 601 nag->ag_fine = ag; 602 if (ag != 0) 603 ag->ag_cors = nag; 604 else 605 ag_finest = nag; 606 nag->ag_cors = ag_cors; 607 if (ag_cors == 0) 608 ag_corsest = nag; 609 else 610 ag_cors->ag_fine = nag; 611 CHECK_AG(); 612} 613 614 615#define NAME0_LEN 14 616static const char * 617rtm_type_name(u_char type) 618{ 619 static const char *rtm_types[] = { 620 "RTM_ADD", 621 "RTM_DELETE", 622 "RTM_CHANGE", 623 "RTM_GET", 624 "RTM_LOSING", 625 "RTM_REDIRECT", 626 "RTM_MISS", 627 "RTM_LOCK", 628 "RTM_OLDADD", 629 "RTM_OLDDEL", 630 "RTM_RESOLVE", 631 "RTM_NEWADDR", 632 "RTM_DELADDR", 633#ifdef RTM_OIFINFO 634 "RTM_OIFINFO", 635#endif 636 "RTM_IFINFO", 637 "RTM_NEWMADDR", 638 "RTM_DELMADDR" 639 }; 640#define NEW_RTM_PAT "RTM type %#x" 641 static char name0[sizeof(NEW_RTM_PAT)+2]; 642 643 644 if (type > sizeof(rtm_types)/sizeof(rtm_types[0]) 645 || type == 0) { 646 snprintf(name0, sizeof(name0), NEW_RTM_PAT, type); 647 return name0; 648 } else { 649 return rtm_types[type-1]; 650 } 651#undef NEW_RTM_PAT 652} 653 654 655/* Trim a mask in a sockaddr 656 * Produce a length of 0 for an address of 0. 657 * Otherwise produce the index of the first zero byte. 658 */ 659void 660#ifdef _HAVE_SIN_LEN 661masktrim(struct sockaddr_in *ap) 662#else 663masktrim(struct sockaddr_in_new *ap) 664#endif 665{ 666 char *cp; 667 668 if (ap->sin_addr.s_addr == 0) { 669 ap->sin_len = 0; 670 return; 671 } 672 cp = (char *)(&ap->sin_addr.s_addr+1); 673 while (*--cp == 0) 674 continue; 675 ap->sin_len = cp - (char*)ap + 1; 676} 677 678 679/* Tell the kernel to add, delete or change a route 680 */ 681static void 682rtioctl(int action, /* RTM_DELETE, etc */ 683 naddr dst, 684 naddr gate, 685 naddr mask, 686 int metric, 687 int flags) 688{ 689 struct { 690 struct rt_msghdr w_rtm; 691 struct sockaddr_in w_dst; 692 struct sockaddr_in w_gate; 693#ifdef _HAVE_SA_LEN 694 struct sockaddr_in w_mask; 695#else 696 struct sockaddr_in_new w_mask; 697#endif 698 } w; 699 long cc; 700# define PAT " %-10s %s metric=%d flags=%#x" 701# define ARGS rtm_type_name(action), rtname(dst,mask,gate), metric, flags 702 703again: 704 memset(&w, 0, sizeof(w)); 705 w.w_rtm.rtm_msglen = sizeof(w); 706 w.w_rtm.rtm_version = RTM_VERSION; 707 w.w_rtm.rtm_type = action; 708 w.w_rtm.rtm_flags = flags; 709 w.w_rtm.rtm_seq = ++rt_sock_seqno; 710 w.w_rtm.rtm_addrs = RTA_DST|RTA_GATEWAY; 711 if (metric != 0 || action == RTM_CHANGE) { 712 w.w_rtm.rtm_rmx.rmx_hopcount = metric; 713 w.w_rtm.rtm_inits |= RTV_HOPCOUNT; 714 } 715 w.w_dst.sin_family = AF_INET; 716 w.w_dst.sin_addr.s_addr = dst; 717 w.w_gate.sin_family = AF_INET; 718 w.w_gate.sin_addr.s_addr = gate; 719#ifdef _HAVE_SA_LEN 720 w.w_dst.sin_len = sizeof(w.w_dst); 721 w.w_gate.sin_len = sizeof(w.w_gate); 722#endif 723 if (mask == HOST_MASK) { 724 w.w_rtm.rtm_flags |= RTF_HOST; 725 w.w_rtm.rtm_msglen -= sizeof(w.w_mask); 726 } else { 727 w.w_rtm.rtm_addrs |= RTA_NETMASK; 728 w.w_mask.sin_addr.s_addr = htonl(mask); 729#ifdef _HAVE_SA_LEN 730 masktrim(&w.w_mask); 731 if (w.w_mask.sin_len == 0) 732 w.w_mask.sin_len = sizeof(long); 733 w.w_rtm.rtm_msglen -= (sizeof(w.w_mask) - w.w_mask.sin_len); 734#endif 735 } 736 737#ifndef NO_INSTALL 738 cc = write(rt_sock, &w, w.w_rtm.rtm_msglen); 739 if (cc < 0) { 740 if (errno == ESRCH 741 && (action == RTM_CHANGE || action == RTM_DELETE)) { 742 trace_act("route disappeared before" PAT, ARGS); 743 if (action == RTM_CHANGE) { 744 action = RTM_ADD; 745 goto again; 746 } 747 return; 748 } 749 msglog("write(rt_sock)" PAT ": %s", ARGS, strerror(errno)); 750 return; 751 } else if (cc != w.w_rtm.rtm_msglen) { 752 msglog("write(rt_sock) wrote %ld instead of %d for" PAT, 753 cc, w.w_rtm.rtm_msglen, ARGS); 754 return; 755 } 756#endif 757 if (TRACEKERNEL) 758 trace_misc("write kernel" PAT, ARGS); 759#undef PAT 760#undef ARGS 761} 762 763 764#define KHASH_SIZE 71 /* should be prime */ 765#define KHASH(a,m) khash_bins[((a) ^ (m)) % KHASH_SIZE] 766static struct khash { 767 struct khash *k_next; 768 naddr k_dst; 769 naddr k_mask; 770 naddr k_gate; 771 short k_metric; 772 u_short k_state; 773#define KS_NEW 0x001 774#define KS_DELETE 0x002 /* need to delete the route */ 775#define KS_ADD 0x004 /* add to the kernel */ 776#define KS_CHANGE 0x008 /* tell kernel to change the route */ 777#define KS_DEL_ADD 0x010 /* delete & add to change the kernel */ 778#define KS_STATIC 0x020 /* Static flag in kernel */ 779#define KS_GATEWAY 0x040 /* G flag in kernel */ 780#define KS_DYNAMIC 0x080 /* result of redirect */ 781#define KS_DELETED 0x100 /* already deleted from kernel */ 782#define KS_CHECK 0x200 783 time_t k_keep; 784#define K_KEEP_LIM 30 785 time_t k_redirect_time; /* when redirected route 1st seen */ 786} *khash_bins[KHASH_SIZE]; 787 788 789static struct khash* 790kern_find(naddr dst, naddr mask, struct khash ***ppk) 791{ 792 struct khash *k, **pk; 793 794 for (pk = &KHASH(dst,mask); (k = *pk) != 0; pk = &k->k_next) { 795 if (k->k_dst == dst && k->k_mask == mask) 796 break; 797 } 798 if (ppk != 0) 799 *ppk = pk; 800 return k; 801} 802 803 804static struct khash* 805kern_add(naddr dst, naddr mask) 806{ 807 struct khash *k, **pk; 808 809 k = kern_find(dst, mask, &pk); 810 if (k != 0) 811 return k; 812 813 k = (struct khash *)rtmalloc(sizeof(*k), "kern_add"); 814 815 memset(k, 0, sizeof(*k)); 816 k->k_dst = dst; 817 k->k_mask = mask; 818 k->k_state = KS_NEW; 819 k->k_keep = now.tv_sec; 820 *pk = k; 821 822 return k; 823} 824 825 826/* If a kernel route has a non-zero metric, check that it is still in the 827 * daemon table, and not deleted by interfaces coming and going. 828 */ 829static void 830kern_check_static(struct khash *k, 831 struct interface *ifp) 832{ 833 struct rt_entry *rt; 834 struct rt_spare new; 835 836 if (k->k_metric == 0) 837 return; 838 839 memset(&new, 0, sizeof(new)); 840 new.rts_ifp = ifp; 841 new.rts_gate = k->k_gate; 842 new.rts_router = (ifp != 0) ? ifp->int_addr : loopaddr; 843 new.rts_metric = k->k_metric; 844 new.rts_time = now.tv_sec; 845 846 rt = rtget(k->k_dst, k->k_mask); 847 if (rt != 0) { 848 if (!(rt->rt_state & RS_STATIC)) 849 rtchange(rt, rt->rt_state | RS_STATIC, &new, 0); 850 } else { 851 rtadd(k->k_dst, k->k_mask, RS_STATIC, &new); 852 } 853} 854 855 856/* operate on a kernel entry 857 */ 858static void 859kern_ioctl(struct khash *k, 860 int action, /* RTM_DELETE, etc */ 861 int flags) 862 863{ 864 switch (action) { 865 case RTM_DELETE: 866 k->k_state &= ~KS_DYNAMIC; 867 if (k->k_state & KS_DELETED) 868 return; 869 k->k_state |= KS_DELETED; 870 break; 871 case RTM_ADD: 872 k->k_state &= ~KS_DELETED; 873 break; 874 case RTM_CHANGE: 875 if (k->k_state & KS_DELETED) { 876 action = RTM_ADD; 877 k->k_state &= ~KS_DELETED; 878 } 879 break; 880 } 881 882 rtioctl(action, k->k_dst, k->k_gate, k->k_mask, k->k_metric, flags); 883} 884 885 886/* add a route the kernel told us 887 */ 888static void 889rtm_add(struct rt_msghdr *rtm, 890 struct rt_addrinfo *info, 891 time_t keep) 892{ 893 struct khash *k; 894 struct interface *ifp; 895 naddr mask; 896 897 898 if (rtm->rtm_flags & RTF_HOST) { 899 mask = HOST_MASK; 900 } else if (INFO_MASK(info) != 0) { 901 mask = ntohl(S_ADDR(INFO_MASK(info))); 902 } else { 903 msglog("ignore %s without mask", rtm_type_name(rtm->rtm_type)); 904 return; 905 } 906 907 k = kern_add(S_ADDR(INFO_DST(info)), mask); 908 if (k->k_state & KS_NEW) 909 k->k_keep = now.tv_sec+keep; 910 if (INFO_GATE(info) == 0) { 911 trace_act("note %s without gateway", 912 rtm_type_name(rtm->rtm_type)); 913 k->k_metric = HOPCNT_INFINITY; 914 } else if (INFO_GATE(info)->sa_family != AF_INET) { 915 trace_act("note %s with gateway AF=%d", 916 rtm_type_name(rtm->rtm_type), 917 INFO_GATE(info)->sa_family); 918 k->k_metric = HOPCNT_INFINITY; 919 } else { 920 k->k_gate = S_ADDR(INFO_GATE(info)); 921 k->k_metric = rtm->rtm_rmx.rmx_hopcount; 922 if (k->k_metric < 0) 923 k->k_metric = 0; 924 else if (k->k_metric > HOPCNT_INFINITY-1) 925 k->k_metric = HOPCNT_INFINITY-1; 926 } 927 k->k_state &= ~(KS_DELETE | KS_ADD | KS_CHANGE | KS_DEL_ADD 928 | KS_DELETED | KS_GATEWAY | KS_STATIC 929 | KS_NEW | KS_CHECK); 930 if (rtm->rtm_flags & RTF_GATEWAY) 931 k->k_state |= KS_GATEWAY; 932 if (rtm->rtm_flags & RTF_STATIC) 933 k->k_state |= KS_STATIC; 934 935 if (0 != (rtm->rtm_flags & (RTF_DYNAMIC | RTF_MODIFIED))) { 936 if (INFO_AUTHOR(info) != 0 937 && INFO_AUTHOR(info)->sa_family == AF_INET) 938 ifp = iflookup(S_ADDR(INFO_AUTHOR(info))); 939 else 940 ifp = 0; 941 if (supplier 942 && (ifp == 0 || !(ifp->int_state & IS_REDIRECT_OK))) { 943 /* Routers are not supposed to listen to redirects, 944 * so delete it if it came via an unknown interface 945 * or the interface does not have special permission. 946 */ 947 k->k_state &= ~KS_DYNAMIC; 948 k->k_state |= KS_DELETE; 949 LIM_SEC(need_kern, 0); 950 trace_act("mark for deletion redirected %s --> %s" 951 " via %s", 952 addrname(k->k_dst, k->k_mask, 0), 953 naddr_ntoa(k->k_gate), 954 ifp ? ifp->int_name : "unknown interface"); 955 } else { 956 k->k_state |= KS_DYNAMIC; 957 k->k_redirect_time = now.tv_sec; 958 trace_act("accept redirected %s --> %s via %s", 959 addrname(k->k_dst, k->k_mask, 0), 960 naddr_ntoa(k->k_gate), 961 ifp ? ifp->int_name : "unknown interface"); 962 } 963 return; 964 } 965 966 /* If it is not a static route, quit until the next comparison 967 * between the kernel and daemon tables, when it will be deleted. 968 */ 969 if (!(k->k_state & KS_STATIC)) { 970 k->k_state |= KS_DELETE; 971 LIM_SEC(need_kern, k->k_keep); 972 return; 973 } 974 975 /* Put static routes with real metrics into the daemon table so 976 * they can be advertised. 977 * 978 * Find the interface toward the gateway. 979 */ 980 ifp = iflookup(k->k_gate); 981 if (ifp == 0) 982 msglog("static route %s --> %s impossibly lacks ifp", 983 addrname(S_ADDR(INFO_DST(info)), mask, 0), 984 naddr_ntoa(k->k_gate)); 985 986 kern_check_static(k, ifp); 987} 988 989 990/* deal with packet loss 991 */ 992static void 993rtm_lose(struct rt_msghdr *rtm, 994 struct rt_addrinfo *info) 995{ 996 if (INFO_GATE(info) == 0 997 || INFO_GATE(info)->sa_family != AF_INET) { 998 trace_act("ignore %s without gateway", 999 rtm_type_name(rtm->rtm_type)); 1000 return; 1001 } 1002 1003 if (rdisc_ok) 1004 rdisc_age(S_ADDR(INFO_GATE(info))); 1005 age(S_ADDR(INFO_GATE(info))); 1006} 1007 1008 1009/* Make the gateway slot of an info structure point to something 1010 * useful. If it is not already useful, but it specifies an interface, 1011 * then fill in the sockaddr_in provided and point it there. 1012 */ 1013static int 1014get_info_gate(struct sockaddr **sap, 1015 struct sockaddr_in *rsin) 1016{ 1017 struct sockaddr_dl *sdl = (struct sockaddr_dl *)*sap; 1018 struct interface *ifp; 1019 1020 if (sdl == 0) 1021 return 0; 1022 if ((sdl)->sdl_family == AF_INET) 1023 return 1; 1024 if ((sdl)->sdl_family != AF_LINK) 1025 return 0; 1026 1027 ifp = ifwithindex(sdl->sdl_index, 1); 1028 if (ifp == 0) 1029 return 0; 1030 1031 rsin->sin_addr.s_addr = ifp->int_addr; 1032#ifdef _HAVE_SA_LEN 1033 rsin->sin_len = sizeof(*rsin); 1034#endif 1035 rsin->sin_family = AF_INET; 1036 *sap = (struct sockaddr*)rsin; 1037 1038 return 1; 1039} 1040 1041 1042/* Clean the kernel table by copying it to the daemon image. 1043 * Eventually the daemon will delete any extra routes. 1044 */ 1045void 1046flush_kern(void) 1047{ 1048 static char *sysctl_buf; 1049 static size_t sysctl_buf_size = 0; 1050 size_t needed; 1051 int mib[6]; 1052 char *next, *lim; 1053 struct rt_msghdr *rtm; 1054 struct sockaddr_in gate_sin; 1055 struct rt_addrinfo info; 1056 int i; 1057 struct khash *k; 1058 1059 1060 for (i = 0; i < KHASH_SIZE; i++) { 1061 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1062 k->k_state |= KS_CHECK; 1063 } 1064 } 1065 1066 mib[0] = CTL_NET; 1067 mib[1] = PF_ROUTE; 1068 mib[2] = 0; /* protocol */ 1069 mib[3] = 0; /* wildcard address family */ 1070 mib[4] = NET_RT_DUMP; 1071 mib[5] = 0; /* no flags */ 1072 for (;;) { 1073 if ((needed = sysctl_buf_size) != 0) { 1074 if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0) 1075 break; 1076 if (errno != ENOMEM && errno != EFAULT) 1077 BADERR(1,"flush_kern: sysctl(RT_DUMP)"); 1078 free(sysctl_buf); 1079 needed = 0; 1080 } 1081 if (sysctl(mib, 6, 0, &needed, 0, 0) < 0) 1082 BADERR(1,"flush_kern: sysctl(RT_DUMP) estimate"); 1083 /* Kludge around the habit of some systems, such as 1084 * BSD/OS 3.1, to not admit how many routes are in the 1085 * kernel, or at least to be quite wrong. 1086 */ 1087 needed += 50*(sizeof(*rtm)+5*sizeof(struct sockaddr)); 1088 sysctl_buf = rtmalloc(sysctl_buf_size = needed, 1089 "flush_kern sysctl(RT_DUMP)"); 1090 } 1091 1092 lim = sysctl_buf + needed; 1093 for (next = sysctl_buf; next < lim; next += rtm->rtm_msglen) { 1094 rtm = (struct rt_msghdr *)next; 1095 if (rtm->rtm_msglen == 0) { 1096 msglog("zero length kernel route at " 1097 " %#lx in buffer %#lx before %#lx", 1098 (u_long)rtm, (u_long)sysctl_buf, (u_long)lim); 1099 break; 1100 } 1101 1102 rt_xaddrs(&info, 1103 (struct sockaddr *)(rtm+1), 1104 (struct sockaddr *)(next + rtm->rtm_msglen), 1105 rtm->rtm_addrs); 1106 1107 if (INFO_DST(&info) == 0 1108 || INFO_DST(&info)->sa_family != AF_INET) 1109 continue; 1110 1111 /* ignore ARP table entries on systems with a merged route 1112 * and ARP table. 1113 */ 1114 if (rtm->rtm_flags & RTF_LLINFO) 1115 continue; 1116 1117#if defined(RTF_CLONED) && defined(__bsdi__) 1118 /* ignore cloned routes 1119 */ 1120 if (rtm->rtm_flags & RTF_CLONED) 1121 continue; 1122#endif 1123 1124 /* ignore multicast addresses 1125 */ 1126 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) 1127 continue; 1128 1129 if (!get_info_gate(&INFO_GATE(&info), &gate_sin)) 1130 continue; 1131 1132 /* Note static routes and interface routes, and also 1133 * preload the image of the kernel table so that 1134 * we can later clean it, as well as avoid making 1135 * unneeded changes. Keep the old kernel routes for a 1136 * few seconds to allow a RIP or router-discovery 1137 * response to be heard. 1138 */ 1139 rtm_add(rtm,&info,MIN_WAITTIME); 1140 } 1141 1142 for (i = 0; i < KHASH_SIZE; i++) { 1143 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1144 if (k->k_state & KS_CHECK) { 1145 msglog("%s --> %s disappeared from kernel", 1146 addrname(k->k_dst, k->k_mask, 0), 1147 naddr_ntoa(k->k_gate)); 1148 del_static(k->k_dst, k->k_mask, k->k_gate, 1); 1149 } 1150 } 1151 } 1152} 1153 1154 1155/* Listen to announcements from the kernel 1156 */ 1157void 1158read_rt(void) 1159{ 1160 long cc; 1161 struct interface *ifp; 1162 struct sockaddr_in gate_sin; 1163 naddr mask, gate; 1164 union { 1165 struct { 1166 struct rt_msghdr rtm; 1167 struct sockaddr addrs[RTAX_MAX]; 1168 } r; 1169 struct if_msghdr ifm; 1170 } m; 1171 char str[100], *strp; 1172 struct rt_addrinfo info; 1173 1174 1175 for (;;) { 1176 cc = read(rt_sock, &m, sizeof(m)); 1177 if (cc <= 0) { 1178 if (cc < 0 && errno != EWOULDBLOCK) 1179 LOGERR("read(rt_sock)"); 1180 return; 1181 } 1182 1183 if (m.r.rtm.rtm_version != RTM_VERSION) { 1184 msglog("bogus routing message version %d", 1185 m.r.rtm.rtm_version); 1186 continue; 1187 } 1188 1189 /* Ignore our own results. 1190 */ 1191 if (m.r.rtm.rtm_type <= RTM_CHANGE 1192 && m.r.rtm.rtm_pid == mypid) { 1193 static int complained = 0; 1194 if (!complained) { 1195 msglog("receiving our own change messages"); 1196 complained = 1; 1197 } 1198 continue; 1199 } 1200 1201 if (m.r.rtm.rtm_type == RTM_IFINFO 1202 || m.r.rtm.rtm_type == RTM_NEWADDR 1203 || m.r.rtm.rtm_type == RTM_DELADDR) { 1204 ifp = ifwithindex(m.ifm.ifm_index, 1205 m.r.rtm.rtm_type != RTM_DELADDR); 1206 if (ifp == 0) 1207 trace_act("note %s with flags %#x" 1208 " for unknown interface index #%d", 1209 rtm_type_name(m.r.rtm.rtm_type), 1210 m.ifm.ifm_flags, 1211 m.ifm.ifm_index); 1212 else 1213 trace_act("note %s with flags %#x for %s", 1214 rtm_type_name(m.r.rtm.rtm_type), 1215 m.ifm.ifm_flags, 1216 ifp->int_name); 1217 1218 /* After being informed of a change to an interface, 1219 * check them all now if the check would otherwise 1220 * be a long time from now, if the interface is 1221 * not known, or if the interface has been turned 1222 * off or on. 1223 */ 1224 if (ifinit_timer.tv_sec-now.tv_sec>=CHECK_BAD_INTERVAL 1225 || ifp == 0 1226 || ((ifp->int_if_flags ^ m.ifm.ifm_flags) 1227 & IFF_UP) != 0) 1228 ifinit_timer.tv_sec = now.tv_sec; 1229 continue; 1230 } 1231#ifdef RTM_OIFINFO 1232 if (m.r.rtm.rtm_type == RTM_OIFINFO) 1233 continue; /* ignore compat message */ 1234#endif 1235 1236 strcpy(str, rtm_type_name(m.r.rtm.rtm_type)); 1237 strp = &str[strlen(str)]; 1238 if (m.r.rtm.rtm_type <= RTM_CHANGE) 1239 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid); 1240 1241 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX], 1242 m.r.rtm.rtm_addrs); 1243 1244 if (INFO_DST(&info) == 0) { 1245 trace_act("ignore %s without dst", str); 1246 continue; 1247 } 1248 1249 if (INFO_DST(&info)->sa_family != AF_INET) { 1250 trace_act("ignore %s for AF %d", str, 1251 INFO_DST(&info)->sa_family); 1252 continue; 1253 } 1254 1255 mask = ((INFO_MASK(&info) != 0) 1256 ? ntohl(S_ADDR(INFO_MASK(&info))) 1257 : (m.r.rtm.rtm_flags & RTF_HOST) 1258 ? HOST_MASK 1259 : std_mask(S_ADDR(INFO_DST(&info)))); 1260 1261 strp += sprintf(strp, ": %s", 1262 addrname(S_ADDR(INFO_DST(&info)), mask, 0)); 1263 1264 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) { 1265 trace_act("ignore multicast %s", str); 1266 continue; 1267 } 1268 1269 if (m.r.rtm.rtm_flags & RTF_LLINFO) { 1270 trace_act("ignore ARP %s", str); 1271 continue; 1272 } 1273 1274#if defined(RTF_CLONED) && defined(__bsdi__) 1275 if (m.r.rtm.rtm_flags & RTF_CLONED) { 1276 trace_act("ignore cloned %s", str); 1277 continue; 1278 } 1279#endif 1280 1281 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) { 1282 gate = S_ADDR(INFO_GATE(&info)); 1283 strp += sprintf(strp, " --> %s", naddr_ntoa(gate)); 1284 } else { 1285 gate = 0; 1286 } 1287 1288 if (INFO_AUTHOR(&info) != 0) 1289 strp += sprintf(strp, " by authority of %s", 1290 saddr_ntoa(INFO_AUTHOR(&info))); 1291 1292 switch (m.r.rtm.rtm_type) { 1293 case RTM_ADD: 1294 case RTM_CHANGE: 1295 case RTM_REDIRECT: 1296 if (m.r.rtm.rtm_errno != 0) { 1297 trace_act("ignore %s with \"%s\" error", 1298 str, strerror(m.r.rtm.rtm_errno)); 1299 } else { 1300 trace_act("%s", str); 1301 rtm_add(&m.r.rtm,&info,0); 1302 } 1303 break; 1304 1305 case RTM_DELETE: 1306 if (m.r.rtm.rtm_errno != 0 1307 && m.r.rtm.rtm_errno != ESRCH) { 1308 trace_act("ignore %s with \"%s\" error", 1309 str, strerror(m.r.rtm.rtm_errno)); 1310 } else { 1311 trace_act("%s", str); 1312 del_static(S_ADDR(INFO_DST(&info)), mask, 1313 gate, 1); 1314 } 1315 break; 1316 1317 case RTM_LOSING: 1318 trace_act("%s", str); 1319 rtm_lose(&m.r.rtm,&info); 1320 break; 1321 1322 default: 1323 trace_act("ignore %s", str); 1324 break; 1325 } 1326 } 1327} 1328 1329 1330/* after aggregating, note routes that belong in the kernel 1331 */ 1332static void 1333kern_out(struct ag_info *ag) 1334{ 1335 struct khash *k; 1336 1337 1338 /* Do not install bad routes if they are not already present. 1339 * This includes routes that had RS_NET_SYN for interfaces that 1340 * recently died. 1341 */ 1342 if (ag->ag_metric == HOPCNT_INFINITY) { 1343 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0); 1344 if (k == 0) 1345 return; 1346 } else { 1347 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask); 1348 } 1349 1350 if (k->k_state & KS_NEW) { 1351 /* will need to add new entry to the kernel table */ 1352 k->k_state = KS_ADD; 1353 if (ag->ag_state & AGS_GATEWAY) 1354 k->k_state |= KS_GATEWAY; 1355 k->k_gate = ag->ag_gate; 1356 k->k_metric = ag->ag_metric; 1357 return; 1358 } 1359 1360 if (k->k_state & KS_STATIC) 1361 return; 1362 1363 /* modify existing kernel entry if necessary */ 1364 if (k->k_gate != ag->ag_gate 1365 || k->k_metric != ag->ag_metric) { 1366 /* Must delete bad interface routes etc. to change them. */ 1367 if (k->k_metric == HOPCNT_INFINITY) 1368 k->k_state |= KS_DEL_ADD; 1369 k->k_gate = ag->ag_gate; 1370 k->k_metric = ag->ag_metric; 1371 k->k_state |= KS_CHANGE; 1372 } 1373 1374 /* If the daemon thinks the route should exist, forget 1375 * about any redirections. 1376 * If the daemon thinks the route should exist, eventually 1377 * override manual intervention by the operator. 1378 */ 1379 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) { 1380 k->k_state &= ~KS_DYNAMIC; 1381 k->k_state |= (KS_ADD | KS_DEL_ADD); 1382 } 1383 1384 if ((k->k_state & KS_GATEWAY) 1385 && !(ag->ag_state & AGS_GATEWAY)) { 1386 k->k_state &= ~KS_GATEWAY; 1387 k->k_state |= (KS_ADD | KS_DEL_ADD); 1388 } else if (!(k->k_state & KS_GATEWAY) 1389 && (ag->ag_state & AGS_GATEWAY)) { 1390 k->k_state |= KS_GATEWAY; 1391 k->k_state |= (KS_ADD | KS_DEL_ADD); 1392 } 1393 1394 /* Deleting-and-adding is necessary to change aspects of a route. 1395 * Just delete instead of deleting and then adding a bad route. 1396 * Otherwise, we want to keep the route in the kernel. 1397 */ 1398 if (k->k_metric == HOPCNT_INFINITY 1399 && (k->k_state & KS_DEL_ADD)) 1400 k->k_state |= KS_DELETE; 1401 else 1402 k->k_state &= ~KS_DELETE; 1403#undef RT 1404} 1405 1406 1407/* ARGSUSED */ 1408static int 1409walk_kern(struct radix_node *rn, 1410 struct walkarg *argp UNUSED) 1411{ 1412#define RT ((struct rt_entry *)rn) 1413 char metric, pref; 1414 u_int ags = 0; 1415 1416 1417 /* Do not install synthetic routes */ 1418 if (RT->rt_state & RS_NET_SYN) 1419 return 0; 1420 1421 if (!(RT->rt_state & RS_IF)) { 1422 /* This is an ordinary route, not for an interface. 1423 */ 1424 1425 /* aggregate, ordinary good routes without regard to 1426 * their metric 1427 */ 1428 pref = 1; 1429 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1430 1431 /* Do not install host routes directly to hosts, to avoid 1432 * interfering with ARP entries in the kernel table. 1433 */ 1434 if (RT_ISHOST(RT) 1435 && ntohl(RT->rt_dst) == RT->rt_gate) 1436 return 0; 1437 1438 } else { 1439 /* This is an interface route. 1440 * Do not install routes for "external" remote interfaces. 1441 */ 1442 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL)) 1443 return 0; 1444 1445 /* Interfaces should override received routes. 1446 */ 1447 pref = 0; 1448 ags |= (AGS_IF | AGS_CORS_GATE); 1449 1450 /* If it is not an interface, or an alias for an interface, 1451 * it must be a "gateway." 1452 * 1453 * If it is a "remote" interface, it is also a "gateway" to 1454 * the kernel if is not an alias. 1455 */ 1456 if (RT->rt_ifp == 0 1457 || (RT->rt_ifp->int_state & IS_REMOTE)) 1458 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1459 } 1460 1461 /* If RIP is off and IRDP is on, let the route to the discovered 1462 * route suppress any RIP routes. Eventually the RIP routes 1463 * will time-out and be deleted. This reaches the steady-state 1464 * quicker. 1465 */ 1466 if ((RT->rt_state & RS_RDISC) && rip_sock < 0) 1467 ags |= AGS_CORS_GATE; 1468 1469 metric = RT->rt_metric; 1470 if (metric == HOPCNT_INFINITY) { 1471 /* if the route is dead, so try hard to aggregate. */ 1472 pref = HOPCNT_INFINITY; 1473 ags |= (AGS_FINE_GATE | AGS_SUPPRESS); 1474 ags &= ~(AGS_IF | AGS_CORS_GATE); 1475 } 1476 1477 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0, 1478 metric,pref, 0, 0, ags, kern_out); 1479 return 0; 1480#undef RT 1481} 1482 1483 1484/* Update the kernel table to match the daemon table. 1485 */ 1486static void 1487fix_kern(void) 1488{ 1489 int i; 1490 struct khash *k, **pk; 1491 1492 1493 need_kern = age_timer; 1494 1495 /* Walk daemon table, updating the copy of the kernel table. 1496 */ 1497 (void)rn_walktree(rhead, walk_kern, 0); 1498 ag_flush(0,0,kern_out); 1499 1500 for (i = 0; i < KHASH_SIZE; i++) { 1501 for (pk = &khash_bins[i]; (k = *pk) != 0; ) { 1502 /* Do not touch static routes */ 1503 if (k->k_state & KS_STATIC) { 1504 kern_check_static(k,0); 1505 pk = &k->k_next; 1506 continue; 1507 } 1508 1509 /* check hold on routes deleted by the operator */ 1510 if (k->k_keep > now.tv_sec) { 1511 /* ensure we check when the hold is over */ 1512 LIM_SEC(need_kern, k->k_keep); 1513 /* mark for the next cycle */ 1514 k->k_state |= KS_DELETE; 1515 pk = &k->k_next; 1516 continue; 1517 } 1518 1519 if ((k->k_state & KS_DELETE) 1520 && !(k->k_state & KS_DYNAMIC)) { 1521 kern_ioctl(k, RTM_DELETE, 0); 1522 *pk = k->k_next; 1523 free(k); 1524 continue; 1525 } 1526 1527 if (k->k_state & KS_DEL_ADD) 1528 kern_ioctl(k, RTM_DELETE, 0); 1529 1530 if (k->k_state & KS_ADD) { 1531 kern_ioctl(k, RTM_ADD, 1532 ((0 != (k->k_state & (KS_GATEWAY 1533 | KS_DYNAMIC))) 1534 ? RTF_GATEWAY : 0)); 1535 } else if (k->k_state & KS_CHANGE) { 1536 kern_ioctl(k, RTM_CHANGE, 1537 ((0 != (k->k_state & (KS_GATEWAY 1538 | KS_DYNAMIC))) 1539 ? RTF_GATEWAY : 0)); 1540 } 1541 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD); 1542 1543 /* Mark this route to be deleted in the next cycle. 1544 * This deletes routes that disappear from the 1545 * daemon table, since the normal aging code 1546 * will clear the bit for routes that have not 1547 * disappeared from the daemon table. 1548 */ 1549 k->k_state |= KS_DELETE; 1550 pk = &k->k_next; 1551 } 1552 } 1553} 1554 1555 1556/* Delete a static route in the image of the kernel table. 1557 */ 1558void 1559del_static(naddr dst, 1560 naddr mask, 1561 naddr gate, 1562 int gone) 1563{ 1564 struct khash *k; 1565 struct rt_entry *rt; 1566 1567 /* Just mark it in the table to be deleted next time the kernel 1568 * table is updated. 1569 * If it has already been deleted, mark it as such, and set its 1570 * keep-timer so that it will not be deleted again for a while. 1571 * This lets the operator delete a route added by the daemon 1572 * and add a replacement. 1573 */ 1574 k = kern_find(dst, mask, 0); 1575 if (k != 0 && (gate == 0 || k->k_gate == gate)) { 1576 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK); 1577 k->k_state |= KS_DELETE; 1578 if (gone) { 1579 k->k_state |= KS_DELETED; 1580 k->k_keep = now.tv_sec + K_KEEP_LIM; 1581 } 1582 } 1583 1584 rt = rtget(dst, mask); 1585 if (rt != 0 && (rt->rt_state & RS_STATIC)) 1586 rtbad(rt); 1587} 1588 1589 1590/* Delete all routes generated from ICMP Redirects that use a given gateway, 1591 * as well as old redirected routes. 1592 */ 1593void 1594del_redirects(naddr bad_gate, 1595 time_t old) 1596{ 1597 int i; 1598 struct khash *k; 1599 1600 1601 for (i = 0; i < KHASH_SIZE; i++) { 1602 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1603 if (!(k->k_state & KS_DYNAMIC) 1604 || (k->k_state & KS_STATIC)) 1605 continue; 1606 1607 if (k->k_gate != bad_gate 1608 && k->k_redirect_time > old 1609 && !supplier) 1610 continue; 1611 1612 k->k_state |= KS_DELETE; 1613 k->k_state &= ~KS_DYNAMIC; 1614 need_kern.tv_sec = now.tv_sec; 1615 trace_act("mark redirected %s --> %s for deletion", 1616 addrname(k->k_dst, k->k_mask, 0), 1617 naddr_ntoa(k->k_gate)); 1618 } 1619 } 1620} 1621 1622 1623/* Start the daemon tables. 1624 */ 1625extern int max_keylen; 1626 1627void 1628rtinit(void) 1629{ 1630 int i; 1631 struct ag_info *ag; 1632 1633 /* Initialize the radix trees */ 1634 max_keylen = sizeof(struct sockaddr_in); 1635 rn_init(); 1636 rn_inithead((void**)&rhead, 32); 1637 1638 /* mark all of the slots in the table free */ 1639 ag_avail = ag_slots; 1640 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) { 1641 ag->ag_fine = ag+1; 1642 ag++; 1643 } 1644} 1645 1646 1647#ifdef _HAVE_SIN_LEN 1648static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET, 0, {0}, {0}}; 1649static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET, 0, {0}, {0}}; 1650#else 1651static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET}; 1652static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET}; 1653#endif 1654 1655 1656static void 1657set_need_flash(void) 1658{ 1659 if (!need_flash) { 1660 need_flash = 1; 1661 /* Do not send the flash update immediately. Wait a little 1662 * while to hear from other routers. 1663 */ 1664 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME; 1665 } 1666} 1667 1668 1669/* Get a particular routing table entry 1670 */ 1671struct rt_entry * 1672rtget(naddr dst, naddr mask) 1673{ 1674 struct rt_entry *rt; 1675 1676 dst_sock.sin_addr.s_addr = dst; 1677 mask_sock.sin_addr.s_addr = htonl(mask); 1678 masktrim(&mask_sock); 1679 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead); 1680 if (!rt 1681 || rt->rt_dst != dst 1682 || rt->rt_mask != mask) 1683 return 0; 1684 1685 return rt; 1686} 1687 1688 1689/* Find a route to dst as the kernel would. 1690 */ 1691struct rt_entry * 1692rtfind(naddr dst) 1693{ 1694 dst_sock.sin_addr.s_addr = dst; 1695 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead); 1696} 1697 1698 1699/* add a route to the table 1700 */ 1701void 1702rtadd(naddr dst, 1703 naddr mask, 1704 u_int state, /* rt_state for the entry */ 1705 struct rt_spare *new) 1706{ 1707 struct rt_entry *rt; 1708 naddr smask; 1709 int i; 1710 struct rt_spare *rts; 1711 1712 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd"); 1713 memset(rt, 0, sizeof(*rt)); 1714 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) 1715 rts->rts_metric = HOPCNT_INFINITY; 1716 1717 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock; 1718 rt->rt_dst = dst; 1719 rt->rt_dst_sock.sin_family = AF_INET; 1720#ifdef _HAVE_SIN_LEN 1721 rt->rt_dst_sock.sin_len = dst_sock.sin_len; 1722#endif 1723 if (mask != HOST_MASK) { 1724 smask = std_mask(dst); 1725 if ((smask & ~mask) == 0 && mask > smask) 1726 state |= RS_SUBNET; 1727 } 1728 mask_sock.sin_addr.s_addr = htonl(mask); 1729 masktrim(&mask_sock); 1730 rt->rt_mask = mask; 1731 rt->rt_state = state; 1732 rt->rt_spares[0] = *new; 1733 rt->rt_time = now.tv_sec; 1734 rt->rt_poison_metric = HOPCNT_INFINITY; 1735 rt->rt_seqno = update_seqno; 1736 1737 if (++total_routes == MAX_ROUTES) 1738 msglog("have maximum (%d) routes", total_routes); 1739 if (TRACEACTIONS) 1740 trace_add_del("Add", rt); 1741 1742 need_kern.tv_sec = now.tv_sec; 1743 set_need_flash(); 1744 1745 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock, 1746 rhead, rt->rt_nodes)) { 1747 msglog("rnh_addaddr() failed for %s mask=%#lx", 1748 naddr_ntoa(dst), (u_long)mask); 1749 free(rt); 1750 } 1751} 1752 1753 1754/* notice a changed route 1755 */ 1756void 1757rtchange(struct rt_entry *rt, 1758 u_int state, /* new state bits */ 1759 struct rt_spare *new, 1760 char *label) 1761{ 1762 if (rt->rt_metric != new->rts_metric) { 1763 /* Fix the kernel immediately if it seems the route 1764 * has gone bad, since there may be a working route that 1765 * aggregates this route. 1766 */ 1767 if (new->rts_metric == HOPCNT_INFINITY) { 1768 need_kern.tv_sec = now.tv_sec; 1769 if (new->rts_time >= now.tv_sec - EXPIRE_TIME) 1770 new->rts_time = now.tv_sec - EXPIRE_TIME; 1771 } 1772 rt->rt_seqno = update_seqno; 1773 set_need_flash(); 1774 } 1775 1776 if (rt->rt_gate != new->rts_gate) { 1777 need_kern.tv_sec = now.tv_sec; 1778 rt->rt_seqno = update_seqno; 1779 set_need_flash(); 1780 } 1781 1782 state |= (rt->rt_state & RS_SUBNET); 1783 1784 /* Keep various things from deciding ageless routes are stale. 1785 */ 1786 if (!AGE_RT(state, new->rts_ifp)) 1787 new->rts_time = now.tv_sec; 1788 1789 if (TRACEACTIONS) 1790 trace_change(rt, state, new, 1791 label ? label : "Chg "); 1792 1793 rt->rt_state = state; 1794 rt->rt_spares[0] = *new; 1795} 1796 1797 1798/* check for a better route among the spares 1799 */ 1800static struct rt_spare * 1801rts_better(struct rt_entry *rt) 1802{ 1803 struct rt_spare *rts, *rts1; 1804 int i; 1805 1806 /* find the best alternative among the spares */ 1807 rts = rt->rt_spares+1; 1808 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) { 1809 if (BETTER_LINK(rt,rts1,rts)) 1810 rts = rts1; 1811 } 1812 1813 return rts; 1814} 1815 1816 1817/* switch to a backup route 1818 */ 1819void 1820rtswitch(struct rt_entry *rt, 1821 struct rt_spare *rts) 1822{ 1823 struct rt_spare swap; 1824 char label[10]; 1825 1826 1827 /* Do not change permanent routes */ 1828 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC 1829 | RS_NET_SYN | RS_IF))) 1830 return; 1831 1832 /* find the best alternative among the spares */ 1833 if (rts == 0) 1834 rts = rts_better(rt); 1835 1836 /* Do not bother if it is not worthwhile. 1837 */ 1838 if (!BETTER_LINK(rt, rts, rt->rt_spares)) 1839 return; 1840 1841 swap = rt->rt_spares[0]; 1842 (void)sprintf(label, "Use #%d", (int)(rts - rt->rt_spares)); 1843 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label); 1844 if (swap.rts_metric == HOPCNT_INFINITY) { 1845 *rts = rts_empty; 1846 } else { 1847 *rts = swap; 1848 } 1849} 1850 1851 1852void 1853rtdelete(struct rt_entry *rt) 1854{ 1855 struct khash *k; 1856 1857 1858 if (TRACEACTIONS) 1859 trace_add_del("Del", rt); 1860 1861 k = kern_find(rt->rt_dst, rt->rt_mask, 0); 1862 if (k != 0) { 1863 k->k_state |= KS_DELETE; 1864 need_kern.tv_sec = now.tv_sec; 1865 } 1866 1867 dst_sock.sin_addr.s_addr = rt->rt_dst; 1868 mask_sock.sin_addr.s_addr = htonl(rt->rt_mask); 1869 masktrim(&mask_sock); 1870 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock, 1871 rhead)) { 1872 msglog("rnh_deladdr() failed"); 1873 } else { 1874 free(rt); 1875 total_routes--; 1876 } 1877} 1878 1879 1880void 1881rts_delete(struct rt_entry *rt, 1882 struct rt_spare *rts) 1883{ 1884 trace_upslot(rt, rts, &rts_empty); 1885 *rts = rts_empty; 1886} 1887 1888 1889/* Get rid of a bad route, and try to switch to a replacement. 1890 */ 1891void 1892rtbad(struct rt_entry *rt) 1893{ 1894 struct rt_spare new; 1895 1896 /* Poison the route */ 1897 new = rt->rt_spares[0]; 1898 new.rts_metric = HOPCNT_INFINITY; 1899 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0); 1900 rtswitch(rt, 0); 1901} 1902 1903 1904/* Junk a RS_NET_SYN or RS_LOCAL route, 1905 * unless it is needed by another interface. 1906 */ 1907void 1908rtbad_sub(struct rt_entry *rt) 1909{ 1910 struct interface *ifp, *ifp1; 1911 struct intnet *intnetp; 1912 u_int state; 1913 1914 1915 ifp1 = 0; 1916 state = 0; 1917 1918 if (rt->rt_state & RS_LOCAL) { 1919 /* Is this the route through loopback for the interface? 1920 * If so, see if it is used by any other interfaces, such 1921 * as a point-to-point interface with the same local address. 1922 */ 1923 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1924 /* Retain it if another interface needs it. 1925 */ 1926 if (ifp->int_addr == rt->rt_ifp->int_addr) { 1927 state |= RS_LOCAL; 1928 ifp1 = ifp; 1929 break; 1930 } 1931 } 1932 1933 } 1934 1935 if (!(state & RS_LOCAL)) { 1936 /* Retain RIPv1 logical network route if there is another 1937 * interface that justifies it. 1938 */ 1939 if (rt->rt_state & RS_NET_SYN) { 1940 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1941 if ((ifp->int_state & IS_NEED_NET_SYN) 1942 && rt->rt_mask == ifp->int_std_mask 1943 && rt->rt_dst == ifp->int_std_addr) { 1944 state |= RS_NET_SYN; 1945 ifp1 = ifp; 1946 break; 1947 } 1948 } 1949 } 1950 1951 /* or if there is an authority route that needs it. */ 1952 for (intnetp = intnets; 1953 intnetp != 0; 1954 intnetp = intnetp->intnet_next) { 1955 if (intnetp->intnet_addr == rt->rt_dst 1956 && intnetp->intnet_mask == rt->rt_mask) { 1957 state |= (RS_NET_SYN | RS_NET_INT); 1958 break; 1959 } 1960 } 1961 } 1962 1963 if (ifp1 != 0 || (state & RS_NET_SYN)) { 1964 struct rt_spare new = rt->rt_spares[0]; 1965 new.rts_ifp = ifp1; 1966 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state), 1967 &new, 0); 1968 } else { 1969 rtbad(rt); 1970 } 1971} 1972 1973 1974/* Called while walking the table looking for sick interfaces 1975 * or after a time change. 1976 */ 1977/* ARGSUSED */ 1978int 1979walk_bad(struct radix_node *rn, 1980 struct walkarg *argp UNUSED) 1981{ 1982#define RT ((struct rt_entry *)rn) 1983 struct rt_spare *rts; 1984 int i; 1985 1986 1987 /* fix any spare routes through the interface 1988 */ 1989 rts = RT->rt_spares; 1990 for (i = NUM_SPARES; i != 1; i--) { 1991 rts++; 1992 if (rts->rts_metric < HOPCNT_INFINITY 1993 && (rts->rts_ifp == 0 1994 || (rts->rts_ifp->int_state & IS_BROKE))) 1995 rts_delete(RT, rts); 1996 } 1997 1998 /* Deal with the main route 1999 */ 2000 /* finished if it has been handled before or if its interface is ok 2001 */ 2002 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE)) 2003 return 0; 2004 2005 /* Bad routes for other than interfaces are easy. 2006 */ 2007 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) { 2008 rtbad(RT); 2009 return 0; 2010 } 2011 2012 rtbad_sub(RT); 2013 return 0; 2014#undef RT 2015} 2016 2017 2018/* Check the age of an individual route. 2019 */ 2020/* ARGSUSED */ 2021static int 2022walk_age(struct radix_node *rn, 2023 struct walkarg *argp UNUSED) 2024{ 2025#define RT ((struct rt_entry *)rn) 2026 struct interface *ifp; 2027 struct rt_spare *rts; 2028 int i; 2029 2030 2031 /* age all of the spare routes, including the primary route 2032 * currently in use 2033 */ 2034 rts = RT->rt_spares; 2035 for (i = NUM_SPARES; i != 0; i--, rts++) { 2036 2037 ifp = rts->rts_ifp; 2038 if (i == NUM_SPARES) { 2039 if (!AGE_RT(RT->rt_state, ifp)) { 2040 /* Keep various things from deciding ageless 2041 * routes are stale 2042 */ 2043 rts->rts_time = now.tv_sec; 2044 continue; 2045 } 2046 2047 /* forget RIP routes after RIP has been turned off. 2048 */ 2049 if (rip_sock < 0) { 2050 rtdelete(RT); 2051 return 0; 2052 } 2053 } 2054 2055 /* age failing routes 2056 */ 2057 if (age_bad_gate == rts->rts_gate 2058 && rts->rts_time >= now_stale) { 2059 rts->rts_time -= SUPPLY_INTERVAL; 2060 } 2061 2062 /* trash the spare routes when they go bad */ 2063 if (rts->rts_metric < HOPCNT_INFINITY 2064 && now_garbage > rts->rts_time 2065 && i != NUM_SPARES) 2066 rts_delete(RT, rts); 2067 } 2068 2069 2070 /* finished if the active route is still fresh */ 2071 if (now_stale <= RT->rt_time) 2072 return 0; 2073 2074 /* try to switch to an alternative */ 2075 rtswitch(RT, 0); 2076 2077 /* Delete a dead route after it has been publically mourned. */ 2078 if (now_garbage > RT->rt_time) { 2079 rtdelete(RT); 2080 return 0; 2081 } 2082 2083 /* Start poisoning a bad route before deleting it. */ 2084 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) { 2085 struct rt_spare new = RT->rt_spares[0]; 2086 new.rts_metric = HOPCNT_INFINITY; 2087 rtchange(RT, RT->rt_state, &new, 0); 2088 } 2089 return 0; 2090} 2091 2092 2093/* Watch for dead routes and interfaces. 2094 */ 2095void 2096age(naddr bad_gate) 2097{ 2098 struct interface *ifp; 2099 int need_query = 0; 2100 2101 /* If not listening to RIP, there is no need to age the routes in 2102 * the table. 2103 */ 2104 age_timer.tv_sec = (now.tv_sec 2105 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL)); 2106 2107 /* Check for dead IS_REMOTE interfaces by timing their 2108 * transmissions. 2109 */ 2110 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 2111 if (!(ifp->int_state & IS_REMOTE)) 2112 continue; 2113 2114 /* ignore unreachable remote interfaces */ 2115 if (!check_remote(ifp)) 2116 continue; 2117 2118 /* Restore remote interface that has become reachable 2119 */ 2120 if (ifp->int_state & IS_BROKE) 2121 if_ok(ifp, "remote "); 2122 2123 if (ifp->int_act_time != NEVER 2124 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) { 2125 msglog("remote interface %s to %s timed out after" 2126 " %ld:%ld", 2127 ifp->int_name, 2128 naddr_ntoa(ifp->int_dstaddr), 2129 (now.tv_sec - ifp->int_act_time)/60, 2130 (now.tv_sec - ifp->int_act_time)%60); 2131 if_sick(ifp); 2132 } 2133 2134 /* If we have not heard from the other router 2135 * recently, ask it. 2136 */ 2137 if (now.tv_sec >= ifp->int_query_time) { 2138 ifp->int_query_time = NEVER; 2139 need_query = 1; 2140 } 2141 } 2142 2143 /* Age routes. */ 2144 age_bad_gate = bad_gate; 2145 (void)rn_walktree(rhead, walk_age, 0); 2146 2147 /* delete old redirected routes to keep the kernel table small 2148 * and prevent blackholes 2149 */ 2150 del_redirects(bad_gate, now.tv_sec-STALE_TIME); 2151 2152 /* Update the kernel routing table. */ 2153 fix_kern(); 2154 2155 /* poke reticent remote gateways */ 2156 if (need_query) 2157 rip_query(); 2158} 2159