1 /* 2 * Copyright (c) 1983, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 #include "defs.h" 33 34 #ifdef __NetBSD__ 35 __RCSID("$NetBSD$"); 36 #elif defined(__FreeBSD__) 37 __RCSID("$FreeBSD$"); 38 #else 39 __RCSID("$Revision: 2.27 $"); 40 #ident "$Revision: 2.27 $" 41 #endif 42 43 static struct rt_spare *rts_better(struct rt_entry *); 44 static struct rt_spare rts_empty = {0,0,0,HOPCNT_INFINITY,0,0,0}; 45 static void set_need_flash(void); 46 #ifdef _HAVE_SIN_LEN 47 static void masktrim(struct sockaddr_in *ap); 48 #else 49 static void masktrim(struct sockaddr_in_new *ap); 50 #endif 51 static void rtbad(struct rt_entry *); 52 53 54 struct radix_node_head *rhead; /* root of the radix tree */ 55 56 int need_flash = 1; /* flash update needed 57 * start =1 to suppress the 1st 58 */ 59 60 struct timeval age_timer; /* next check of old routes */ 61 struct timeval need_kern = { /* need to update kernel table */ 62 EPOCH+MIN_WAITTIME-1, 0 63 }; 64 65 int stopint; 66 67 int total_routes; 68 69 /* zap any old routes through this gateway */ 70 static naddr age_bad_gate; 71 72 73 /* It is desirable to "aggregate" routes, to combine differing routes of 74 * the same metric and next hop into a common route with a smaller netmask 75 * or to suppress redundant routes, routes that add no information to 76 * routes with smaller netmasks. 77 * 78 * A route is redundant if and only if any and all routes with smaller 79 * but matching netmasks and nets are the same. Since routes are 80 * kept sorted in the radix tree, redundant routes always come second. 81 * 82 * There are two kinds of aggregations. First, two routes of the same bit 83 * mask and differing only in the least significant bit of the network 84 * number can be combined into a single route with a coarser mask. 85 * 86 * Second, a route can be suppressed in favor of another route with a more 87 * coarse mask provided no incompatible routes with intermediate masks 88 * are present. The second kind of aggregation involves suppressing routes. 89 * A route must not be suppressed if an incompatible route exists with 90 * an intermediate mask, since the suppressed route would be covered 91 * by the intermediate. 92 * 93 * This code relies on the radix tree walk encountering routes 94 * sorted first by address, with the smallest address first. 95 */ 96 97 static struct ag_info ag_slots[NUM_AG_SLOTS], *ag_avail, *ag_corsest, *ag_finest; 98 99 /* #define DEBUG_AG */ 100 #ifdef DEBUG_AG 101 #define CHECK_AG() {int acnt = 0; struct ag_info *cag; \ 102 for (cag = ag_avail; cag != NULL; cag = cag->ag_fine) \ 103 acnt++; \ 104 for (cag = ag_corsest; cag != NULL; cag = cag->ag_fine) \ 105 acnt++; \ 106 if (acnt != NUM_AG_SLOTS) { \ 107 (void)fflush(stderr); \ 108 abort(); \ 109 } \ 110 } 111 #else 112 #define CHECK_AG() 113 #endif 114 115 116 /* Output the contents of an aggregation table slot. 117 * This function must always be immediately followed with the deletion 118 * of the target slot. 119 */ 120 static void 121 ag_out(struct ag_info *ag, 122 void (*out)(struct ag_info *)) 123 { 124 struct ag_info *ag_cors; 125 naddr bit; 126 127 128 /* Forget it if this route should not be output for split-horizon. */ 129 if (ag->ag_state & AGS_SPLIT_HZ) 130 return; 131 132 /* If we output both the even and odd twins, then the immediate parent, 133 * if it is present, is redundant, unless the parent manages to 134 * aggregate into something coarser. 135 * On successive calls, this code detects the even and odd twins, 136 * and marks the parent. 137 * 138 * Note that the order in which the radix tree code emits routes 139 * ensures that the twins are seen before the parent is emitted. 140 */ 141 ag_cors = ag->ag_cors; 142 if (ag_cors != NULL 143 && ag_cors->ag_mask == ag->ag_mask<<1 144 && ag_cors->ag_dst_h == (ag->ag_dst_h & ag_cors->ag_mask)) { 145 ag_cors->ag_state |= ((ag_cors->ag_dst_h == ag->ag_dst_h) 146 ? AGS_REDUN0 147 : AGS_REDUN1); 148 } 149 150 /* Skip it if this route is itself redundant. 151 * 152 * It is ok to change the contents of the slot here, since it is 153 * always deleted next. 154 */ 155 if (ag->ag_state & AGS_REDUN0) { 156 if (ag->ag_state & AGS_REDUN1) 157 return; /* quit if fully redundant */ 158 /* make it finer if it is half-redundant */ 159 bit = (-ag->ag_mask) >> 1; 160 ag->ag_dst_h |= bit; 161 ag->ag_mask |= bit; 162 163 } else if (ag->ag_state & AGS_REDUN1) { 164 /* make it finer if it is half-redundant */ 165 bit = (-ag->ag_mask) >> 1; 166 ag->ag_mask |= bit; 167 } 168 out(ag); 169 } 170 171 172 static void 173 ag_del(struct ag_info *ag) 174 { 175 CHECK_AG(); 176 177 if (ag->ag_cors == NULL) 178 ag_corsest = ag->ag_fine; 179 else 180 ag->ag_cors->ag_fine = ag->ag_fine; 181 182 if (ag->ag_fine == NULL) 183 ag_finest = ag->ag_cors; 184 else 185 ag->ag_fine->ag_cors = ag->ag_cors; 186 187 ag->ag_fine = ag_avail; 188 ag_avail = ag; 189 190 CHECK_AG(); 191 } 192 193 194 /* Flush routes waiting for aggregation. 195 * This must not suppress a route unless it is known that among all 196 * routes with coarser masks that match it, the one with the longest 197 * mask is appropriate. This is ensured by scanning the routes 198 * in lexical order, and with the most restrictive mask first 199 * among routes to the same destination. 200 */ 201 void 202 ag_flush(naddr lim_dst_h, /* flush routes to here */ 203 naddr lim_mask, /* matching this mask */ 204 void (*out)(struct ag_info *)) 205 { 206 struct ag_info *ag, *ag_cors; 207 naddr dst_h; 208 209 210 for (ag = ag_finest; 211 ag != NULL && ag->ag_mask >= lim_mask; 212 ag = ag_cors) { 213 ag_cors = ag->ag_cors; 214 215 /* work on only the specified routes */ 216 dst_h = ag->ag_dst_h; 217 if ((dst_h & lim_mask) != lim_dst_h) 218 continue; 219 220 if (!(ag->ag_state & AGS_SUPPRESS)) 221 ag_out(ag, out); 222 223 else for ( ; ; ag_cors = ag_cors->ag_cors) { 224 /* Look for a route that can suppress the 225 * current route */ 226 if (ag_cors == NULL) { 227 /* failed, so output it and look for 228 * another route to work on 229 */ 230 ag_out(ag, out); 231 break; 232 } 233 234 if ((dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h) { 235 /* We found a route with a coarser mask that 236 * aggregates the current target. 237 * 238 * If it has a different next hop, it 239 * cannot replace the target, so output 240 * the target. 241 */ 242 if (ag->ag_gate != ag_cors->ag_gate 243 && !(ag->ag_state & AGS_FINE_GATE) 244 && !(ag_cors->ag_state & AGS_CORS_GATE)) { 245 ag_out(ag, out); 246 break; 247 } 248 249 /* If the coarse route has a good enough 250 * metric, it suppresses the target. 251 * If the suppressed target was redundant, 252 * then mark the suppressor redundant. 253 */ 254 if (ag_cors->ag_pref <= ag->ag_pref) { 255 if (AG_IS_REDUN(ag->ag_state) 256 && ag_cors->ag_mask==ag->ag_mask<<1) { 257 if (ag_cors->ag_dst_h == dst_h) 258 ag_cors->ag_state |= AGS_REDUN0; 259 else 260 ag_cors->ag_state |= AGS_REDUN1; 261 } 262 if (ag->ag_tag != ag_cors->ag_tag) 263 ag_cors->ag_tag = 0; 264 if (ag->ag_nhop != ag_cors->ag_nhop) 265 ag_cors->ag_nhop = 0; 266 break; 267 } 268 } 269 } 270 271 /* That route has either been output or suppressed */ 272 ag_cors = ag->ag_cors; 273 ag_del(ag); 274 } 275 276 CHECK_AG(); 277 } 278 279 280 /* Try to aggregate a route with previous routes. 281 */ 282 void 283 ag_check(naddr dst, 284 naddr mask, 285 naddr gate, 286 naddr nhop, 287 char metric, 288 char pref, 289 u_int new_seqno, 290 u_short tag, 291 u_short state, 292 void (*out)(struct ag_info *)) /* output using this */ 293 { 294 struct ag_info *ag, *nag, *ag_cors; 295 naddr xaddr; 296 int x; 297 298 dst = ntohl(dst); 299 300 /* Punt non-contiguous subnet masks. 301 * 302 * (X & -X) contains a single bit if and only if X is a power of 2. 303 * (X + (X & -X)) == 0 if and only if X is a power of 2. 304 */ 305 if ((mask & -mask) + mask != 0) { 306 struct ag_info nc_ag; 307 308 nc_ag.ag_dst_h = dst; 309 nc_ag.ag_mask = mask; 310 nc_ag.ag_gate = gate; 311 nc_ag.ag_nhop = nhop; 312 nc_ag.ag_metric = metric; 313 nc_ag.ag_pref = pref; 314 nc_ag.ag_tag = tag; 315 nc_ag.ag_state = state; 316 nc_ag.ag_seqno = new_seqno; 317 out(&nc_ag); 318 return; 319 } 320 321 /* Search for the right slot in the aggregation table. 322 */ 323 ag_cors = NULL; 324 ag = ag_corsest; 325 while (ag != NULL) { 326 if (ag->ag_mask >= mask) 327 break; 328 329 /* Suppress old routes (i.e. combine with compatible routes 330 * with coarser masks) as we look for the right slot in the 331 * aggregation table for the new route. 332 * A route to an address less than the current destination 333 * will not be affected by the current route or any route 334 * seen hereafter. That means it is safe to suppress it. 335 * This check keeps poor routes (e.g. with large hop counts) 336 * from preventing suppression of finer routes. 337 */ 338 if (ag_cors != NULL 339 && ag->ag_dst_h < dst 340 && (ag->ag_state & AGS_SUPPRESS) 341 && ag_cors->ag_pref <= ag->ag_pref 342 && (ag->ag_dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h 343 && (ag_cors->ag_gate == ag->ag_gate 344 || (ag->ag_state & AGS_FINE_GATE) 345 || (ag_cors->ag_state & AGS_CORS_GATE))) { 346 /* If the suppressed target was redundant, 347 * then mark the suppressor redundant. 348 */ 349 if (AG_IS_REDUN(ag->ag_state) 350 && ag_cors->ag_mask == ag->ag_mask<<1) { 351 if (ag_cors->ag_dst_h == dst) 352 ag_cors->ag_state |= AGS_REDUN0; 353 else 354 ag_cors->ag_state |= AGS_REDUN1; 355 } 356 if (ag->ag_tag != ag_cors->ag_tag) 357 ag_cors->ag_tag = 0; 358 if (ag->ag_nhop != ag_cors->ag_nhop) 359 ag_cors->ag_nhop = 0; 360 ag_del(ag); 361 CHECK_AG(); 362 } else { 363 ag_cors = ag; 364 } 365 ag = ag_cors->ag_fine; 366 } 367 368 /* If we find the even/odd twin of the new route, and if the 369 * masks and so forth are equal, we can aggregate them. 370 * We can probably promote one of the pair. 371 * 372 * Since the routes are encountered in lexical order, 373 * the new route must be odd. However, the second or later 374 * times around this loop, it could be the even twin promoted 375 * from the even/odd pair of twins of the finer route. 376 */ 377 while (ag != NULL 378 && ag->ag_mask == mask 379 && ((ag->ag_dst_h ^ dst) & (mask<<1)) == 0) { 380 381 /* Here we know the target route and the route in the current 382 * slot have the same netmasks and differ by at most the 383 * last bit. They are either for the same destination, or 384 * for an even/odd pair of destinations. 385 */ 386 if (ag->ag_dst_h == dst) { 387 /* We have two routes to the same destination. 388 * Routes are encountered in lexical order, so a 389 * route is never promoted until the parent route is 390 * already present. So we know that the new route is 391 * a promoted (or aggregated) pair and the route 392 * already in the slot is the explicit route. 393 * 394 * Prefer the best route if their metrics differ, 395 * or the aggregated one if not, following a sort 396 * of longest-match rule. 397 */ 398 if (pref <= ag->ag_pref) { 399 ag->ag_gate = gate; 400 ag->ag_nhop = nhop; 401 ag->ag_tag = tag; 402 ag->ag_metric = metric; 403 ag->ag_pref = pref; 404 if (ag->ag_seqno < new_seqno) 405 ag->ag_seqno = new_seqno; 406 x = ag->ag_state; 407 ag->ag_state = state; 408 state = x; 409 } 410 411 /* Some bits are set if they are set on either route, 412 * except when the route is for an interface. 413 */ 414 if (!(ag->ag_state & AGS_IF)) 415 ag->ag_state |= (state & (AGS_AGGREGATE_EITHER 416 | AGS_REDUN0 417 | AGS_REDUN1)); 418 return; 419 } 420 421 /* If one of the routes can be promoted and the other can 422 * be suppressed, it may be possible to combine them or 423 * worthwhile to promote one. 424 * 425 * Any route that can be promoted is always 426 * marked to be eligible to be suppressed. 427 */ 428 if (!((state & AGS_AGGREGATE) 429 && (ag->ag_state & AGS_SUPPRESS)) 430 && !((ag->ag_state & AGS_AGGREGATE) 431 && (state & AGS_SUPPRESS))) 432 break; 433 434 /* A pair of even/odd twin routes can be combined 435 * if either is redundant, or if they are via the 436 * same gateway and have the same metric. 437 */ 438 if (AG_IS_REDUN(ag->ag_state) 439 || AG_IS_REDUN(state) 440 || (ag->ag_gate == gate 441 && ag->ag_pref == pref 442 && (state & ag->ag_state & AGS_AGGREGATE) != 0)) { 443 444 /* We have both the even and odd pairs. 445 * Since the routes are encountered in order, 446 * the route in the slot must be the even twin. 447 * 448 * Combine and promote (aggregate) the pair of routes. 449 */ 450 if (new_seqno < ag->ag_seqno) 451 new_seqno = ag->ag_seqno; 452 if (!AG_IS_REDUN(state)) 453 state &= ~AGS_REDUN1; 454 if (AG_IS_REDUN(ag->ag_state)) 455 state |= AGS_REDUN0; 456 else 457 state &= ~AGS_REDUN0; 458 state |= (ag->ag_state & AGS_AGGREGATE_EITHER); 459 if (ag->ag_tag != tag) 460 tag = 0; 461 if (ag->ag_nhop != nhop) 462 nhop = 0; 463 464 /* Get rid of the even twin that was already 465 * in the slot. 466 */ 467 ag_del(ag); 468 469 } else if (ag->ag_pref >= pref 470 && (ag->ag_state & AGS_AGGREGATE)) { 471 /* If we cannot combine the pair, maybe the route 472 * with the worse metric can be promoted. 473 * 474 * Promote the old, even twin, by giving its slot 475 * in the table to the new, odd twin. 476 */ 477 ag->ag_dst_h = dst; 478 479 xaddr = ag->ag_gate; 480 ag->ag_gate = gate; 481 gate = xaddr; 482 483 xaddr = ag->ag_nhop; 484 ag->ag_nhop = nhop; 485 nhop = xaddr; 486 487 x = ag->ag_tag; 488 ag->ag_tag = tag; 489 tag = x; 490 491 /* The promoted route is even-redundant only if the 492 * even twin was fully redundant. It is not 493 * odd-redundant because the odd-twin will still be 494 * in the table. 495 */ 496 x = ag->ag_state; 497 if (!AG_IS_REDUN(x)) 498 x &= ~AGS_REDUN0; 499 x &= ~AGS_REDUN1; 500 ag->ag_state = state; 501 state = x; 502 503 x = ag->ag_metric; 504 ag->ag_metric = metric; 505 metric = x; 506 507 x = ag->ag_pref; 508 ag->ag_pref = pref; 509 pref = x; 510 511 /* take the newest sequence number */ 512 if (new_seqno <= ag->ag_seqno) 513 new_seqno = ag->ag_seqno; 514 else 515 ag->ag_seqno = new_seqno; 516 517 } else { 518 if (!(state & AGS_AGGREGATE)) 519 break; /* cannot promote either twin */ 520 521 /* Promote the new, odd twin by shaving its 522 * mask and address. 523 * The promoted route is odd-redundant only if the 524 * odd twin was fully redundant. It is not 525 * even-redundant because the even twin is still in 526 * the table. 527 */ 528 if (!AG_IS_REDUN(state)) 529 state &= ~AGS_REDUN1; 530 state &= ~AGS_REDUN0; 531 if (new_seqno < ag->ag_seqno) 532 new_seqno = ag->ag_seqno; 533 else 534 ag->ag_seqno = new_seqno; 535 } 536 537 mask <<= 1; 538 dst &= mask; 539 540 if (ag_cors == NULL) { 541 ag = ag_corsest; 542 break; 543 } 544 ag = ag_cors; 545 ag_cors = ag->ag_cors; 546 } 547 548 /* When we can no longer promote and combine routes, 549 * flush the old route in the target slot. Also flush 550 * any finer routes that we know will never be aggregated by 551 * the new route. 552 * 553 * In case we moved toward coarser masks, 554 * get back where we belong 555 */ 556 if (ag != NULL 557 && ag->ag_mask < mask) { 558 ag_cors = ag; 559 ag = ag->ag_fine; 560 } 561 562 /* Empty the target slot 563 */ 564 if (ag != NULL && ag->ag_mask == mask) { 565 ag_flush(ag->ag_dst_h, ag->ag_mask, out); 566 ag = (ag_cors == NULL) ? ag_corsest : ag_cors->ag_fine; 567 } 568 569 #ifdef DEBUG_AG 570 (void)fflush(stderr); 571 if (ag == NULL && ag_cors != ag_finest) 572 abort(); 573 if (ag_cors == NULL && ag != ag_corsest) 574 abort(); 575 if (ag != NULL && ag->ag_cors != ag_cors) 576 abort(); 577 if (ag_cors != NULL && ag_cors->ag_fine != ag) 578 abort(); 579 CHECK_AG(); 580 #endif 581 582 /* Save the new route on the end of the table. 583 */ 584 nag = ag_avail; 585 ag_avail = nag->ag_fine; 586 587 nag->ag_dst_h = dst; 588 nag->ag_mask = mask; 589 nag->ag_gate = gate; 590 nag->ag_nhop = nhop; 591 nag->ag_metric = metric; 592 nag->ag_pref = pref; 593 nag->ag_tag = tag; 594 nag->ag_state = state; 595 nag->ag_seqno = new_seqno; 596 597 nag->ag_fine = ag; 598 if (ag != NULL) 599 ag->ag_cors = nag; 600 else 601 ag_finest = nag; 602 nag->ag_cors = ag_cors; 603 if (ag_cors == NULL) 604 ag_corsest = nag; 605 else 606 ag_cors->ag_fine = nag; 607 CHECK_AG(); 608 } 609 610 static const char * 611 rtm_type_name(u_char type) 612 { 613 static const char * const rtm_types[] = { 614 "RTM_ADD", 615 "RTM_DELETE", 616 "RTM_CHANGE", 617 "RTM_GET", 618 "RTM_LOSING", 619 "RTM_REDIRECT", 620 "RTM_MISS", 621 "RTM_LOCK", 622 "RTM_OLDADD", 623 "RTM_OLDDEL", 624 "RTM_RESOLVE", 625 "RTM_NEWADDR", 626 "RTM_DELADDR", 627 #ifdef RTM_OIFINFO 628 "RTM_OIFINFO", 629 #endif 630 "RTM_IFINFO", 631 "RTM_NEWMADDR", 632 "RTM_DELMADDR" 633 }; 634 #define NEW_RTM_PAT "RTM type %#x" 635 static char name0[sizeof(NEW_RTM_PAT)+2]; 636 637 638 if (type > sizeof(rtm_types)/sizeof(rtm_types[0]) 639 || type == 0) { 640 snprintf(name0, sizeof(name0), NEW_RTM_PAT, type); 641 return name0; 642 } else { 643 return rtm_types[type-1]; 644 } 645 #undef NEW_RTM_PAT 646 } 647 648 649 /* Trim a mask in a sockaddr 650 * Produce a length of 0 for an address of 0. 651 * Otherwise produce the index of the first zero byte. 652 */ 653 void 654 #ifdef _HAVE_SIN_LEN 655 masktrim(struct sockaddr_in *ap) 656 #else 657 masktrim(struct sockaddr_in_new *ap) 658 #endif 659 { 660 char *cp; 661 662 if (ap->sin_addr.s_addr == 0) { 663 ap->sin_len = 0; 664 return; 665 } 666 cp = (char *)(&ap->sin_addr.s_addr+1); 667 while (*--cp == 0) 668 continue; 669 ap->sin_len = cp - (char*)ap + 1; 670 } 671 672 673 /* Tell the kernel to add, delete or change a route 674 */ 675 static void 676 rtioctl(int action, /* RTM_DELETE, etc */ 677 naddr dst, 678 naddr gate, 679 naddr mask, 680 int metric, 681 int flags) 682 { 683 struct { 684 struct rt_msghdr w_rtm; 685 struct sockaddr_in w_dst; 686 struct sockaddr_in w_gate; 687 #ifdef _HAVE_SA_LEN 688 struct sockaddr_in w_mask; 689 #else 690 struct sockaddr_in_new w_mask; 691 #endif 692 } w; 693 long cc; 694 # define PAT " %-10s %s metric=%d flags=%#x" 695 # define ARGS rtm_type_name(action), rtname(dst,mask,gate), metric, flags 696 697 again: 698 memset(&w, 0, sizeof(w)); 699 w.w_rtm.rtm_msglen = sizeof(w); 700 w.w_rtm.rtm_version = RTM_VERSION; 701 w.w_rtm.rtm_type = action; 702 w.w_rtm.rtm_flags = flags; 703 w.w_rtm.rtm_seq = ++rt_sock_seqno; 704 w.w_rtm.rtm_addrs = RTA_DST|RTA_GATEWAY; 705 if (metric != 0 || action == RTM_CHANGE) { 706 w.w_rtm.rtm_rmx.rmx_hopcount = metric; 707 w.w_rtm.rtm_inits |= RTV_HOPCOUNT; 708 } 709 w.w_dst.sin_family = AF_INET; 710 w.w_dst.sin_addr.s_addr = dst; 711 w.w_gate.sin_family = AF_INET; 712 w.w_gate.sin_addr.s_addr = gate; 713 #ifdef _HAVE_SA_LEN 714 w.w_dst.sin_len = sizeof(w.w_dst); 715 w.w_gate.sin_len = sizeof(w.w_gate); 716 #endif 717 if (mask == HOST_MASK) { 718 w.w_rtm.rtm_flags |= RTF_HOST; 719 w.w_rtm.rtm_msglen -= sizeof(w.w_mask); 720 } else { 721 w.w_rtm.rtm_addrs |= RTA_NETMASK; 722 w.w_mask.sin_addr.s_addr = htonl(mask); 723 #ifdef _HAVE_SA_LEN 724 masktrim(&w.w_mask); 725 if (w.w_mask.sin_len == 0) 726 w.w_mask.sin_len = sizeof(long); 727 w.w_rtm.rtm_msglen -= (sizeof(w.w_mask) - w.w_mask.sin_len); 728 #endif 729 } 730 731 #ifndef NO_INSTALL 732 cc = write(rt_sock, &w, w.w_rtm.rtm_msglen); 733 if (cc < 0) { 734 if (errno == ESRCH 735 && (action == RTM_CHANGE || action == RTM_DELETE)) { 736 trace_act("route disappeared before" PAT, ARGS); 737 if (action == RTM_CHANGE) { 738 action = RTM_ADD; 739 goto again; 740 } 741 return; 742 } 743 msglog("write(rt_sock)" PAT ": %s", ARGS, strerror(errno)); 744 return; 745 } else if (cc != w.w_rtm.rtm_msglen) { 746 msglog("write(rt_sock) wrote %ld instead of %d for" PAT, 747 cc, w.w_rtm.rtm_msglen, ARGS); 748 return; 749 } 750 #endif 751 if (TRACEKERNEL) 752 trace_misc("write kernel" PAT, ARGS); 753 #undef PAT 754 #undef ARGS 755 } 756 757 758 #define KHASH_SIZE 71 /* should be prime */ 759 #define KHASH(a,m) khash_bins[((a) ^ (m)) % KHASH_SIZE] 760 static struct khash { 761 struct khash *k_next; 762 naddr k_dst; 763 naddr k_mask; 764 naddr k_gate; 765 short k_metric; 766 u_short k_state; 767 #define KS_NEW 0x001 768 #define KS_DELETE 0x002 /* need to delete the route */ 769 #define KS_ADD 0x004 /* add to the kernel */ 770 #define KS_CHANGE 0x008 /* tell kernel to change the route */ 771 #define KS_DEL_ADD 0x010 /* delete & add to change the kernel */ 772 #define KS_STATIC 0x020 /* Static flag in kernel */ 773 #define KS_GATEWAY 0x040 /* G flag in kernel */ 774 #define KS_DYNAMIC 0x080 /* result of redirect */ 775 #define KS_DELETED 0x100 /* already deleted from kernel */ 776 #define KS_CHECK 0x200 777 time_t k_keep; 778 #define K_KEEP_LIM 30 779 time_t k_redirect_time; /* when redirected route 1st seen */ 780 } *khash_bins[KHASH_SIZE]; 781 782 783 static struct khash* 784 kern_find(naddr dst, naddr mask, struct khash ***ppk) 785 { 786 struct khash *k, **pk; 787 788 for (pk = &KHASH(dst,mask); (k = *pk) != NULL; pk = &k->k_next) { 789 if (k->k_dst == dst && k->k_mask == mask) 790 break; 791 } 792 if (ppk != NULL) 793 *ppk = pk; 794 return k; 795 } 796 797 798 static struct khash* 799 kern_add(naddr dst, naddr mask) 800 { 801 struct khash *k, **pk; 802 803 k = kern_find(dst, mask, &pk); 804 if (k != NULL) 805 return k; 806 807 k = (struct khash *)rtmalloc(sizeof(*k), "kern_add"); 808 809 memset(k, 0, sizeof(*k)); 810 k->k_dst = dst; 811 k->k_mask = mask; 812 k->k_state = KS_NEW; 813 k->k_keep = now.tv_sec; 814 *pk = k; 815 816 return k; 817 } 818 819 820 /* If a kernel route has a non-zero metric, check that it is still in the 821 * daemon table, and not deleted by interfaces coming and going. 822 */ 823 static void 824 kern_check_static(struct khash *k, 825 struct interface *ifp) 826 { 827 struct rt_entry *rt; 828 struct rt_spare new; 829 830 if (k->k_metric == 0) 831 return; 832 833 memset(&new, 0, sizeof(new)); 834 new.rts_ifp = ifp; 835 new.rts_gate = k->k_gate; 836 new.rts_router = (ifp != NULL) ? ifp->int_addr : loopaddr; 837 new.rts_metric = k->k_metric; 838 new.rts_time = now.tv_sec; 839 840 rt = rtget(k->k_dst, k->k_mask); 841 if (rt != NULL) { 842 if (!(rt->rt_state & RS_STATIC)) 843 rtchange(rt, rt->rt_state | RS_STATIC, &new, 0); 844 } else { 845 rtadd(k->k_dst, k->k_mask, RS_STATIC, &new); 846 } 847 } 848 849 850 /* operate on a kernel entry 851 */ 852 static void 853 kern_ioctl(struct khash *k, 854 int action, /* RTM_DELETE, etc */ 855 int flags) 856 857 { 858 switch (action) { 859 case RTM_DELETE: 860 k->k_state &= ~KS_DYNAMIC; 861 if (k->k_state & KS_DELETED) 862 return; 863 k->k_state |= KS_DELETED; 864 break; 865 case RTM_ADD: 866 k->k_state &= ~KS_DELETED; 867 break; 868 case RTM_CHANGE: 869 if (k->k_state & KS_DELETED) { 870 action = RTM_ADD; 871 k->k_state &= ~KS_DELETED; 872 } 873 break; 874 } 875 876 rtioctl(action, k->k_dst, k->k_gate, k->k_mask, k->k_metric, flags); 877 } 878 879 880 /* add a route the kernel told us 881 */ 882 static void 883 rtm_add(struct rt_msghdr *rtm, 884 struct rt_addrinfo *info, 885 time_t keep) 886 { 887 struct khash *k; 888 struct interface *ifp; 889 naddr mask; 890 891 892 if (rtm->rtm_flags & RTF_HOST) { 893 mask = HOST_MASK; 894 } else if (INFO_MASK(info) != 0) { 895 mask = ntohl(S_ADDR(INFO_MASK(info))); 896 } else { 897 msglog("ignore %s without mask", rtm_type_name(rtm->rtm_type)); 898 return; 899 } 900 901 k = kern_add(S_ADDR(INFO_DST(info)), mask); 902 if (k->k_state & KS_NEW) 903 k->k_keep = now.tv_sec+keep; 904 if (INFO_GATE(info) == 0) { 905 trace_act("note %s without gateway", 906 rtm_type_name(rtm->rtm_type)); 907 k->k_metric = HOPCNT_INFINITY; 908 } else if (INFO_GATE(info)->sa_family != AF_INET) { 909 trace_act("note %s with gateway AF=%d", 910 rtm_type_name(rtm->rtm_type), 911 INFO_GATE(info)->sa_family); 912 k->k_metric = HOPCNT_INFINITY; 913 } else { 914 k->k_gate = S_ADDR(INFO_GATE(info)); 915 k->k_metric = rtm->rtm_rmx.rmx_hopcount; 916 if (k->k_metric < 0) 917 k->k_metric = 0; 918 else if (k->k_metric > HOPCNT_INFINITY-1) 919 k->k_metric = HOPCNT_INFINITY-1; 920 } 921 k->k_state &= ~(KS_DELETE | KS_ADD | KS_CHANGE | KS_DEL_ADD 922 | KS_DELETED | KS_GATEWAY | KS_STATIC 923 | KS_NEW | KS_CHECK); 924 if (rtm->rtm_flags & RTF_GATEWAY) 925 k->k_state |= KS_GATEWAY; 926 if (rtm->rtm_flags & RTF_STATIC) 927 k->k_state |= KS_STATIC; 928 929 if (0 != (rtm->rtm_flags & (RTF_DYNAMIC | RTF_MODIFIED))) { 930 if (INFO_AUTHOR(info) != 0 931 && INFO_AUTHOR(info)->sa_family == AF_INET) 932 ifp = iflookup(S_ADDR(INFO_AUTHOR(info))); 933 else 934 ifp = NULL; 935 if (supplier 936 && (ifp == NULL || !(ifp->int_state & IS_REDIRECT_OK))) { 937 /* Routers are not supposed to listen to redirects, 938 * so delete it if it came via an unknown interface 939 * or the interface does not have special permission. 940 */ 941 k->k_state &= ~KS_DYNAMIC; 942 k->k_state |= KS_DELETE; 943 LIM_SEC(need_kern, 0); 944 trace_act("mark for deletion redirected %s --> %s" 945 " via %s", 946 addrname(k->k_dst, k->k_mask, 0), 947 naddr_ntoa(k->k_gate), 948 ifp ? ifp->int_name : "unknown interface"); 949 } else { 950 k->k_state |= KS_DYNAMIC; 951 k->k_redirect_time = now.tv_sec; 952 trace_act("accept redirected %s --> %s via %s", 953 addrname(k->k_dst, k->k_mask, 0), 954 naddr_ntoa(k->k_gate), 955 ifp ? ifp->int_name : "unknown interface"); 956 } 957 return; 958 } 959 960 /* If it is not a static route, quit until the next comparison 961 * between the kernel and daemon tables, when it will be deleted. 962 */ 963 if (!(k->k_state & KS_STATIC)) { 964 k->k_state |= KS_DELETE; 965 LIM_SEC(need_kern, k->k_keep); 966 return; 967 } 968 969 /* Put static routes with real metrics into the daemon table so 970 * they can be advertised. 971 * 972 * Find the interface toward the gateway. 973 */ 974 ifp = iflookup(k->k_gate); 975 if (ifp == NULL) 976 msglog("static route %s --> %s impossibly lacks ifp", 977 addrname(S_ADDR(INFO_DST(info)), mask, 0), 978 naddr_ntoa(k->k_gate)); 979 980 kern_check_static(k, ifp); 981 } 982 983 984 /* deal with packet loss 985 */ 986 static void 987 rtm_lose(struct rt_msghdr *rtm, 988 struct rt_addrinfo *info) 989 { 990 if (INFO_GATE(info) == 0 991 || INFO_GATE(info)->sa_family != AF_INET) { 992 trace_act("ignore %s without gateway", 993 rtm_type_name(rtm->rtm_type)); 994 return; 995 } 996 997 if (rdisc_ok) 998 rdisc_age(S_ADDR(INFO_GATE(info))); 999 age(S_ADDR(INFO_GATE(info))); 1000 } 1001 1002 1003 /* Make the gateway slot of an info structure point to something 1004 * useful. If it is not already useful, but it specifies an interface, 1005 * then fill in the sockaddr_in provided and point it there. 1006 */ 1007 static int 1008 get_info_gate(struct sockaddr **sap, 1009 struct sockaddr_in *rsin) 1010 { 1011 struct sockaddr_dl *sdl = (struct sockaddr_dl *)*sap; 1012 struct interface *ifp; 1013 1014 if (sdl == NULL) 1015 return 0; 1016 if ((sdl)->sdl_family == AF_INET) 1017 return 1; 1018 if ((sdl)->sdl_family != AF_LINK) 1019 return 0; 1020 1021 ifp = ifwithindex(sdl->sdl_index, 1); 1022 if (ifp == NULL) 1023 return 0; 1024 1025 rsin->sin_addr.s_addr = ifp->int_addr; 1026 #ifdef _HAVE_SA_LEN 1027 rsin->sin_len = sizeof(*rsin); 1028 #endif 1029 rsin->sin_family = AF_INET; 1030 *sap = (struct sockaddr*)rsin; 1031 1032 return 1; 1033 } 1034 1035 1036 /* Clean the kernel table by copying it to the daemon image. 1037 * Eventually the daemon will delete any extra routes. 1038 */ 1039 void 1040 flush_kern(void) 1041 { 1042 static char *sysctl_buf; 1043 static size_t sysctl_buf_size = 0; 1044 size_t needed; 1045 int mib[6]; 1046 char *next, *lim; 1047 struct rt_msghdr *rtm; 1048 struct sockaddr_in gate_sin; 1049 struct rt_addrinfo info; 1050 int i; 1051 struct khash *k; 1052 1053 1054 for (i = 0; i < KHASH_SIZE; i++) { 1055 for (k = khash_bins[i]; k != NULL; k = k->k_next) { 1056 k->k_state |= KS_CHECK; 1057 } 1058 } 1059 1060 mib[0] = CTL_NET; 1061 mib[1] = PF_ROUTE; 1062 mib[2] = 0; /* protocol */ 1063 mib[3] = 0; /* wildcard address family */ 1064 mib[4] = NET_RT_DUMP; 1065 mib[5] = 0; /* no flags */ 1066 for (;;) { 1067 if ((needed = sysctl_buf_size) != 0) { 1068 if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0) 1069 break; 1070 if (errno != ENOMEM && errno != EFAULT) 1071 BADERR(1,"flush_kern: sysctl(RT_DUMP)"); 1072 free(sysctl_buf); 1073 needed = 0; 1074 } 1075 if (sysctl(mib, 6, 0, &needed, 0, 0) < 0) 1076 BADERR(1,"flush_kern: sysctl(RT_DUMP) estimate"); 1077 /* Kludge around the habit of some systems, such as 1078 * BSD/OS 3.1, to not admit how many routes are in the 1079 * kernel, or at least to be quite wrong. 1080 */ 1081 needed += 50*(sizeof(*rtm)+5*sizeof(struct sockaddr)); 1082 sysctl_buf = rtmalloc(sysctl_buf_size = needed, 1083 "flush_kern sysctl(RT_DUMP)"); 1084 } 1085 1086 lim = sysctl_buf + needed; 1087 for (next = sysctl_buf; next < lim; next += rtm->rtm_msglen) { 1088 rtm = (struct rt_msghdr *)next; 1089 if (rtm->rtm_msglen == 0) { 1090 msglog("zero length kernel route at " 1091 " %#lx in buffer %#lx before %#lx", 1092 (u_long)rtm, (u_long)sysctl_buf, (u_long)lim); 1093 break; 1094 } 1095 1096 rt_xaddrs(&info, 1097 (struct sockaddr *)(rtm+1), 1098 (struct sockaddr *)(next + rtm->rtm_msglen), 1099 rtm->rtm_addrs); 1100 1101 if (INFO_DST(&info) == 0 1102 || INFO_DST(&info)->sa_family != AF_INET) 1103 continue; 1104 1105 #if defined (RTF_LLINFO) 1106 /* ignore ARP table entries on systems with a merged route 1107 * and ARP table. 1108 */ 1109 if (rtm->rtm_flags & RTF_LLINFO) 1110 continue; 1111 #endif 1112 #if defined(RTF_WASCLONED) && defined(__FreeBSD__) 1113 /* ignore cloned routes 1114 */ 1115 if (rtm->rtm_flags & RTF_WASCLONED) 1116 continue; 1117 #endif 1118 1119 /* ignore multicast addresses 1120 */ 1121 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) 1122 continue; 1123 1124 if (!get_info_gate(&INFO_GATE(&info), &gate_sin)) 1125 continue; 1126 1127 /* Note static routes and interface routes, and also 1128 * preload the image of the kernel table so that 1129 * we can later clean it, as well as avoid making 1130 * unneeded changes. Keep the old kernel routes for a 1131 * few seconds to allow a RIP or router-discovery 1132 * response to be heard. 1133 */ 1134 rtm_add(rtm,&info,MIN_WAITTIME); 1135 } 1136 1137 for (i = 0; i < KHASH_SIZE; i++) { 1138 for (k = khash_bins[i]; k != NULL; k = k->k_next) { 1139 if (k->k_state & KS_CHECK) { 1140 msglog("%s --> %s disappeared from kernel", 1141 addrname(k->k_dst, k->k_mask, 0), 1142 naddr_ntoa(k->k_gate)); 1143 del_static(k->k_dst, k->k_mask, k->k_gate, 1); 1144 } 1145 } 1146 } 1147 } 1148 1149 1150 /* Listen to announcements from the kernel 1151 */ 1152 void 1153 read_rt(void) 1154 { 1155 long cc; 1156 struct interface *ifp; 1157 struct sockaddr_in gate_sin; 1158 naddr mask, gate; 1159 union { 1160 struct { 1161 struct rt_msghdr rtm; 1162 struct sockaddr addrs[RTAX_MAX]; 1163 } r; 1164 struct if_msghdr ifm; 1165 } m; 1166 char str[100], *strp; 1167 struct rt_addrinfo info; 1168 1169 1170 for (;;) { 1171 cc = read(rt_sock, &m, sizeof(m)); 1172 if (cc <= 0) { 1173 if (cc < 0 && errno != EWOULDBLOCK) 1174 LOGERR("read(rt_sock)"); 1175 return; 1176 } 1177 1178 if (m.r.rtm.rtm_version != RTM_VERSION) { 1179 msglog("bogus routing message version %d", 1180 m.r.rtm.rtm_version); 1181 continue; 1182 } 1183 1184 /* Ignore our own results. 1185 */ 1186 if (m.r.rtm.rtm_type <= RTM_CHANGE 1187 && m.r.rtm.rtm_pid == mypid) { 1188 static int complained = 0; 1189 if (!complained) { 1190 msglog("receiving our own change messages"); 1191 complained = 1; 1192 } 1193 continue; 1194 } 1195 1196 if (m.r.rtm.rtm_type == RTM_IFINFO 1197 || m.r.rtm.rtm_type == RTM_NEWADDR 1198 || m.r.rtm.rtm_type == RTM_DELADDR) { 1199 ifp = ifwithindex(m.ifm.ifm_index, 1200 m.r.rtm.rtm_type != RTM_DELADDR); 1201 if (ifp == NULL) 1202 trace_act("note %s with flags %#x" 1203 " for unknown interface index #%d", 1204 rtm_type_name(m.r.rtm.rtm_type), 1205 m.ifm.ifm_flags, 1206 m.ifm.ifm_index); 1207 else 1208 trace_act("note %s with flags %#x for %s", 1209 rtm_type_name(m.r.rtm.rtm_type), 1210 m.ifm.ifm_flags, 1211 ifp->int_name); 1212 1213 /* After being informed of a change to an interface, 1214 * check them all now if the check would otherwise 1215 * be a long time from now, if the interface is 1216 * not known, or if the interface has been turned 1217 * off or on. 1218 */ 1219 if (ifinit_timer.tv_sec-now.tv_sec>=CHECK_BAD_INTERVAL 1220 || ifp == NULL 1221 || ((ifp->int_if_flags ^ m.ifm.ifm_flags) 1222 & IFF_UP) != 0) 1223 ifinit_timer.tv_sec = now.tv_sec; 1224 continue; 1225 } 1226 #ifdef RTM_OIFINFO 1227 if (m.r.rtm.rtm_type == RTM_OIFINFO) 1228 continue; /* ignore compat message */ 1229 #endif 1230 1231 strlcpy(str, rtm_type_name(m.r.rtm.rtm_type), sizeof(str)); 1232 strp = &str[strlen(str)]; 1233 if (m.r.rtm.rtm_type <= RTM_CHANGE) 1234 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid); 1235 1236 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX], 1237 m.r.rtm.rtm_addrs); 1238 1239 if (INFO_DST(&info) == 0) { 1240 trace_act("ignore %s without dst", str); 1241 continue; 1242 } 1243 1244 if (INFO_DST(&info)->sa_family != AF_INET) { 1245 trace_act("ignore %s for AF %d", str, 1246 INFO_DST(&info)->sa_family); 1247 continue; 1248 } 1249 1250 mask = ((INFO_MASK(&info) != 0) 1251 ? ntohl(S_ADDR(INFO_MASK(&info))) 1252 : (m.r.rtm.rtm_flags & RTF_HOST) 1253 ? HOST_MASK 1254 : std_mask(S_ADDR(INFO_DST(&info)))); 1255 1256 strp += sprintf(strp, ": %s", 1257 addrname(S_ADDR(INFO_DST(&info)), mask, 0)); 1258 1259 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) { 1260 trace_act("ignore multicast %s", str); 1261 continue; 1262 } 1263 1264 #if defined(RTF_LLINFO) 1265 if (m.r.rtm.rtm_flags & RTF_LLINFO) { 1266 trace_act("ignore ARP %s", str); 1267 continue; 1268 } 1269 #endif 1270 1271 #if defined(RTF_WASCLONED) && defined(__FreeBSD__) 1272 if (m.r.rtm.rtm_flags & RTF_WASCLONED) { 1273 trace_act("ignore cloned %s", str); 1274 continue; 1275 } 1276 #endif 1277 1278 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) { 1279 gate = S_ADDR(INFO_GATE(&info)); 1280 strp += sprintf(strp, " --> %s", naddr_ntoa(gate)); 1281 } else { 1282 gate = 0; 1283 } 1284 1285 if (INFO_AUTHOR(&info) != 0) 1286 strp += sprintf(strp, " by authority of %s", 1287 saddr_ntoa(INFO_AUTHOR(&info))); 1288 1289 switch (m.r.rtm.rtm_type) { 1290 case RTM_ADD: 1291 case RTM_CHANGE: 1292 case RTM_REDIRECT: 1293 if (m.r.rtm.rtm_errno != 0) { 1294 trace_act("ignore %s with \"%s\" error", 1295 str, strerror(m.r.rtm.rtm_errno)); 1296 } else { 1297 trace_act("%s", str); 1298 rtm_add(&m.r.rtm,&info,0); 1299 } 1300 break; 1301 1302 case RTM_DELETE: 1303 if (m.r.rtm.rtm_errno != 0 1304 && m.r.rtm.rtm_errno != ESRCH) { 1305 trace_act("ignore %s with \"%s\" error", 1306 str, strerror(m.r.rtm.rtm_errno)); 1307 } else { 1308 trace_act("%s", str); 1309 del_static(S_ADDR(INFO_DST(&info)), mask, 1310 gate, 1); 1311 } 1312 break; 1313 1314 case RTM_LOSING: 1315 trace_act("%s", str); 1316 rtm_lose(&m.r.rtm,&info); 1317 break; 1318 1319 default: 1320 trace_act("ignore %s", str); 1321 break; 1322 } 1323 } 1324 } 1325 1326 1327 /* after aggregating, note routes that belong in the kernel 1328 */ 1329 static void 1330 kern_out(struct ag_info *ag) 1331 { 1332 struct khash *k; 1333 1334 1335 /* Do not install bad routes if they are not already present. 1336 * This includes routes that had RS_NET_SYN for interfaces that 1337 * recently died. 1338 */ 1339 if (ag->ag_metric == HOPCNT_INFINITY) { 1340 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0); 1341 if (k == NULL) 1342 return; 1343 } else { 1344 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask); 1345 } 1346 1347 if (k->k_state & KS_NEW) { 1348 /* will need to add new entry to the kernel table */ 1349 k->k_state = KS_ADD; 1350 if (ag->ag_state & AGS_GATEWAY) 1351 k->k_state |= KS_GATEWAY; 1352 k->k_gate = ag->ag_gate; 1353 k->k_metric = ag->ag_metric; 1354 return; 1355 } 1356 1357 if (k->k_state & KS_STATIC) 1358 return; 1359 1360 /* modify existing kernel entry if necessary */ 1361 if (k->k_gate != ag->ag_gate 1362 || k->k_metric != ag->ag_metric) { 1363 /* Must delete bad interface routes etc. to change them. */ 1364 if (k->k_metric == HOPCNT_INFINITY) 1365 k->k_state |= KS_DEL_ADD; 1366 k->k_gate = ag->ag_gate; 1367 k->k_metric = ag->ag_metric; 1368 k->k_state |= KS_CHANGE; 1369 } 1370 1371 /* If the daemon thinks the route should exist, forget 1372 * about any redirections. 1373 * If the daemon thinks the route should exist, eventually 1374 * override manual intervention by the operator. 1375 */ 1376 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) { 1377 k->k_state &= ~KS_DYNAMIC; 1378 k->k_state |= (KS_ADD | KS_DEL_ADD); 1379 } 1380 1381 if ((k->k_state & KS_GATEWAY) 1382 && !(ag->ag_state & AGS_GATEWAY)) { 1383 k->k_state &= ~KS_GATEWAY; 1384 k->k_state |= (KS_ADD | KS_DEL_ADD); 1385 } else if (!(k->k_state & KS_GATEWAY) 1386 && (ag->ag_state & AGS_GATEWAY)) { 1387 k->k_state |= KS_GATEWAY; 1388 k->k_state |= (KS_ADD | KS_DEL_ADD); 1389 } 1390 1391 /* Deleting-and-adding is necessary to change aspects of a route. 1392 * Just delete instead of deleting and then adding a bad route. 1393 * Otherwise, we want to keep the route in the kernel. 1394 */ 1395 if (k->k_metric == HOPCNT_INFINITY 1396 && (k->k_state & KS_DEL_ADD)) 1397 k->k_state |= KS_DELETE; 1398 else 1399 k->k_state &= ~KS_DELETE; 1400 #undef RT 1401 } 1402 1403 1404 /* ARGSUSED */ 1405 static int 1406 walk_kern(struct radix_node *rn, 1407 struct walkarg *argp UNUSED) 1408 { 1409 #define RT ((struct rt_entry *)rn) 1410 char metric, pref; 1411 u_int ags = 0; 1412 1413 1414 /* Do not install synthetic routes */ 1415 if (RT->rt_state & RS_NET_SYN) 1416 return 0; 1417 1418 if (!(RT->rt_state & RS_IF)) { 1419 /* This is an ordinary route, not for an interface. 1420 */ 1421 1422 /* aggregate, ordinary good routes without regard to 1423 * their metric 1424 */ 1425 pref = 1; 1426 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1427 1428 /* Do not install host routes directly to hosts, to avoid 1429 * interfering with ARP entries in the kernel table. 1430 */ 1431 if (RT_ISHOST(RT) 1432 && ntohl(RT->rt_dst) == RT->rt_gate) 1433 return 0; 1434 1435 } else { 1436 /* This is an interface route. 1437 * Do not install routes for "external" remote interfaces. 1438 */ 1439 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL)) 1440 return 0; 1441 1442 /* Interfaces should override received routes. 1443 */ 1444 pref = 0; 1445 ags |= (AGS_IF | AGS_CORS_GATE); 1446 1447 /* If it is not an interface, or an alias for an interface, 1448 * it must be a "gateway." 1449 * 1450 * If it is a "remote" interface, it is also a "gateway" to 1451 * the kernel if is not an alias. 1452 */ 1453 if (RT->rt_ifp == 0 1454 || (RT->rt_ifp->int_state & IS_REMOTE)) 1455 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1456 } 1457 1458 /* If RIP is off and IRDP is on, let the route to the discovered 1459 * route suppress any RIP routes. Eventually the RIP routes 1460 * will time-out and be deleted. This reaches the steady-state 1461 * quicker. 1462 */ 1463 if ((RT->rt_state & RS_RDISC) && rip_sock < 0) 1464 ags |= AGS_CORS_GATE; 1465 1466 metric = RT->rt_metric; 1467 if (metric == HOPCNT_INFINITY) { 1468 /* if the route is dead, so try hard to aggregate. */ 1469 pref = HOPCNT_INFINITY; 1470 ags |= (AGS_FINE_GATE | AGS_SUPPRESS); 1471 ags &= ~(AGS_IF | AGS_CORS_GATE); 1472 } 1473 1474 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0, 1475 metric,pref, 0, 0, ags, kern_out); 1476 return 0; 1477 #undef RT 1478 } 1479 1480 1481 /* Update the kernel table to match the daemon table. 1482 */ 1483 static void 1484 fix_kern(void) 1485 { 1486 int i; 1487 struct khash *k, **pk; 1488 1489 1490 need_kern = age_timer; 1491 1492 /* Walk daemon table, updating the copy of the kernel table. 1493 */ 1494 (void)rn_walktree(rhead, walk_kern, 0); 1495 ag_flush(0,0,kern_out); 1496 1497 for (i = 0; i < KHASH_SIZE; i++) { 1498 for (pk = &khash_bins[i]; (k = *pk) != NULL; ) { 1499 /* Do not touch static routes */ 1500 if (k->k_state & KS_STATIC) { 1501 kern_check_static(k,0); 1502 pk = &k->k_next; 1503 continue; 1504 } 1505 1506 /* check hold on routes deleted by the operator */ 1507 if (k->k_keep > now.tv_sec) { 1508 /* ensure we check when the hold is over */ 1509 LIM_SEC(need_kern, k->k_keep); 1510 /* mark for the next cycle */ 1511 k->k_state |= KS_DELETE; 1512 pk = &k->k_next; 1513 continue; 1514 } 1515 1516 if ((k->k_state & KS_DELETE) 1517 && !(k->k_state & KS_DYNAMIC)) { 1518 kern_ioctl(k, RTM_DELETE, 0); 1519 *pk = k->k_next; 1520 free(k); 1521 continue; 1522 } 1523 1524 if (k->k_state & KS_DEL_ADD) 1525 kern_ioctl(k, RTM_DELETE, 0); 1526 1527 if (k->k_state & KS_ADD) { 1528 kern_ioctl(k, RTM_ADD, 1529 ((0 != (k->k_state & (KS_GATEWAY 1530 | KS_DYNAMIC))) 1531 ? RTF_GATEWAY : 0)); 1532 } else if (k->k_state & KS_CHANGE) { 1533 kern_ioctl(k, RTM_CHANGE, 1534 ((0 != (k->k_state & (KS_GATEWAY 1535 | KS_DYNAMIC))) 1536 ? RTF_GATEWAY : 0)); 1537 } 1538 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD); 1539 1540 /* Mark this route to be deleted in the next cycle. 1541 * This deletes routes that disappear from the 1542 * daemon table, since the normal aging code 1543 * will clear the bit for routes that have not 1544 * disappeared from the daemon table. 1545 */ 1546 k->k_state |= KS_DELETE; 1547 pk = &k->k_next; 1548 } 1549 } 1550 } 1551 1552 1553 /* Delete a static route in the image of the kernel table. 1554 */ 1555 void 1556 del_static(naddr dst, 1557 naddr mask, 1558 naddr gate, 1559 int gone) 1560 { 1561 struct khash *k; 1562 struct rt_entry *rt; 1563 1564 /* Just mark it in the table to be deleted next time the kernel 1565 * table is updated. 1566 * If it has already been deleted, mark it as such, and set its 1567 * keep-timer so that it will not be deleted again for a while. 1568 * This lets the operator delete a route added by the daemon 1569 * and add a replacement. 1570 */ 1571 k = kern_find(dst, mask, 0); 1572 if (k != NULL && (gate == 0 || k->k_gate == gate)) { 1573 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK); 1574 k->k_state |= KS_DELETE; 1575 if (gone) { 1576 k->k_state |= KS_DELETED; 1577 k->k_keep = now.tv_sec + K_KEEP_LIM; 1578 } 1579 } 1580 1581 rt = rtget(dst, mask); 1582 if (rt != NULL && (rt->rt_state & RS_STATIC)) 1583 rtbad(rt); 1584 } 1585 1586 1587 /* Delete all routes generated from ICMP Redirects that use a given gateway, 1588 * as well as old redirected routes. 1589 */ 1590 void 1591 del_redirects(naddr bad_gate, 1592 time_t old) 1593 { 1594 int i; 1595 struct khash *k; 1596 1597 1598 for (i = 0; i < KHASH_SIZE; i++) { 1599 for (k = khash_bins[i]; k != NULL; k = k->k_next) { 1600 if (!(k->k_state & KS_DYNAMIC) 1601 || (k->k_state & KS_STATIC)) 1602 continue; 1603 1604 if (k->k_gate != bad_gate 1605 && k->k_redirect_time > old 1606 && !supplier) 1607 continue; 1608 1609 k->k_state |= KS_DELETE; 1610 k->k_state &= ~KS_DYNAMIC; 1611 need_kern.tv_sec = now.tv_sec; 1612 trace_act("mark redirected %s --> %s for deletion", 1613 addrname(k->k_dst, k->k_mask, 0), 1614 naddr_ntoa(k->k_gate)); 1615 } 1616 } 1617 } 1618 1619 1620 /* Start the daemon tables. 1621 */ 1622 extern int max_keylen; 1623 1624 void 1625 rtinit(void) 1626 { 1627 int i; 1628 struct ag_info *ag; 1629 1630 /* Initialize the radix trees */ 1631 max_keylen = sizeof(struct sockaddr_in); 1632 rn_init(); 1633 rn_inithead(&rhead, 32); 1634 1635 /* mark all of the slots in the table free */ 1636 ag_avail = ag_slots; 1637 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) { 1638 ag->ag_fine = ag+1; 1639 ag++; 1640 } 1641 } 1642 1643 1644 #ifdef _HAVE_SIN_LEN 1645 static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET, 0, {0}, {0}}; 1646 static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET, 0, {0}, {0}}; 1647 #else 1648 static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET}; 1649 static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET}; 1650 #endif 1651 1652 1653 static void 1654 set_need_flash(void) 1655 { 1656 if (!need_flash) { 1657 need_flash = 1; 1658 /* Do not send the flash update immediately. Wait a little 1659 * while to hear from other routers. 1660 */ 1661 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME; 1662 } 1663 } 1664 1665 1666 /* Get a particular routing table entry 1667 */ 1668 struct rt_entry * 1669 rtget(naddr dst, naddr mask) 1670 { 1671 struct rt_entry *rt; 1672 1673 dst_sock.sin_addr.s_addr = dst; 1674 mask_sock.sin_addr.s_addr = htonl(mask); 1675 masktrim(&mask_sock); 1676 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead); 1677 if (!rt 1678 || rt->rt_dst != dst 1679 || rt->rt_mask != mask) 1680 return 0; 1681 1682 return rt; 1683 } 1684 1685 1686 /* Find a route to dst as the kernel would. 1687 */ 1688 struct rt_entry * 1689 rtfind(naddr dst) 1690 { 1691 dst_sock.sin_addr.s_addr = dst; 1692 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead); 1693 } 1694 1695 1696 /* add a route to the table 1697 */ 1698 void 1699 rtadd(naddr dst, 1700 naddr mask, 1701 u_int state, /* rt_state for the entry */ 1702 struct rt_spare *new) 1703 { 1704 struct rt_entry *rt; 1705 naddr smask; 1706 int i; 1707 struct rt_spare *rts; 1708 1709 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd"); 1710 memset(rt, 0, sizeof(*rt)); 1711 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) 1712 rts->rts_metric = HOPCNT_INFINITY; 1713 1714 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock; 1715 rt->rt_dst = dst; 1716 rt->rt_dst_sock.sin_family = AF_INET; 1717 #ifdef _HAVE_SIN_LEN 1718 rt->rt_dst_sock.sin_len = dst_sock.sin_len; 1719 #endif 1720 if (mask != HOST_MASK) { 1721 smask = std_mask(dst); 1722 if ((smask & ~mask) == 0 && mask > smask) 1723 state |= RS_SUBNET; 1724 } 1725 mask_sock.sin_addr.s_addr = htonl(mask); 1726 masktrim(&mask_sock); 1727 rt->rt_mask = mask; 1728 rt->rt_state = state; 1729 rt->rt_spares[0] = *new; 1730 rt->rt_time = now.tv_sec; 1731 rt->rt_poison_metric = HOPCNT_INFINITY; 1732 rt->rt_seqno = update_seqno; 1733 1734 if (++total_routes == MAX_ROUTES) 1735 msglog("have maximum (%d) routes", total_routes); 1736 if (TRACEACTIONS) 1737 trace_add_del("Add", rt); 1738 1739 need_kern.tv_sec = now.tv_sec; 1740 set_need_flash(); 1741 1742 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock, 1743 rhead, rt->rt_nodes)) { 1744 msglog("rnh_addaddr() failed for %s mask=%#lx", 1745 naddr_ntoa(dst), (u_long)mask); 1746 free(rt); 1747 } 1748 } 1749 1750 1751 /* notice a changed route 1752 */ 1753 void 1754 rtchange(struct rt_entry *rt, 1755 u_int state, /* new state bits */ 1756 struct rt_spare *new, 1757 char *label) 1758 { 1759 if (rt->rt_metric != new->rts_metric) { 1760 /* Fix the kernel immediately if it seems the route 1761 * has gone bad, since there may be a working route that 1762 * aggregates this route. 1763 */ 1764 if (new->rts_metric == HOPCNT_INFINITY) { 1765 need_kern.tv_sec = now.tv_sec; 1766 if (new->rts_time >= now.tv_sec - EXPIRE_TIME) 1767 new->rts_time = now.tv_sec - EXPIRE_TIME; 1768 } 1769 rt->rt_seqno = update_seqno; 1770 set_need_flash(); 1771 } 1772 1773 if (rt->rt_gate != new->rts_gate) { 1774 need_kern.tv_sec = now.tv_sec; 1775 rt->rt_seqno = update_seqno; 1776 set_need_flash(); 1777 } 1778 1779 state |= (rt->rt_state & RS_SUBNET); 1780 1781 /* Keep various things from deciding ageless routes are stale. 1782 */ 1783 if (!AGE_RT(state, new->rts_ifp)) 1784 new->rts_time = now.tv_sec; 1785 1786 if (TRACEACTIONS) 1787 trace_change(rt, state, new, 1788 label ? label : "Chg "); 1789 1790 rt->rt_state = state; 1791 rt->rt_spares[0] = *new; 1792 } 1793 1794 1795 /* check for a better route among the spares 1796 */ 1797 static struct rt_spare * 1798 rts_better(struct rt_entry *rt) 1799 { 1800 struct rt_spare *rts, *rts1; 1801 int i; 1802 1803 /* find the best alternative among the spares */ 1804 rts = rt->rt_spares+1; 1805 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) { 1806 if (BETTER_LINK(rt,rts1,rts)) 1807 rts = rts1; 1808 } 1809 1810 return rts; 1811 } 1812 1813 1814 /* switch to a backup route 1815 */ 1816 void 1817 rtswitch(struct rt_entry *rt, 1818 struct rt_spare *rts) 1819 { 1820 struct rt_spare swap; 1821 char label[10]; 1822 1823 1824 /* Do not change permanent routes */ 1825 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC 1826 | RS_NET_SYN | RS_IF))) 1827 return; 1828 1829 /* find the best alternative among the spares */ 1830 if (rts == NULL) 1831 rts = rts_better(rt); 1832 1833 /* Do not bother if it is not worthwhile. 1834 */ 1835 if (!BETTER_LINK(rt, rts, rt->rt_spares)) 1836 return; 1837 1838 swap = rt->rt_spares[0]; 1839 (void)sprintf(label, "Use #%d", (int)(rts - rt->rt_spares)); 1840 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label); 1841 if (swap.rts_metric == HOPCNT_INFINITY) { 1842 *rts = rts_empty; 1843 } else { 1844 *rts = swap; 1845 } 1846 } 1847 1848 1849 void 1850 rtdelete(struct rt_entry *rt) 1851 { 1852 struct khash *k; 1853 1854 1855 if (TRACEACTIONS) 1856 trace_add_del("Del", rt); 1857 1858 k = kern_find(rt->rt_dst, rt->rt_mask, 0); 1859 if (k != NULL) { 1860 k->k_state |= KS_DELETE; 1861 need_kern.tv_sec = now.tv_sec; 1862 } 1863 1864 dst_sock.sin_addr.s_addr = rt->rt_dst; 1865 mask_sock.sin_addr.s_addr = htonl(rt->rt_mask); 1866 masktrim(&mask_sock); 1867 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock, 1868 rhead)) { 1869 msglog("rnh_deladdr() failed"); 1870 } else { 1871 free(rt); 1872 total_routes--; 1873 } 1874 } 1875 1876 1877 void 1878 rts_delete(struct rt_entry *rt, 1879 struct rt_spare *rts) 1880 { 1881 trace_upslot(rt, rts, &rts_empty); 1882 *rts = rts_empty; 1883 } 1884 1885 1886 /* Get rid of a bad route, and try to switch to a replacement. 1887 */ 1888 static void 1889 rtbad(struct rt_entry *rt) 1890 { 1891 struct rt_spare new; 1892 1893 /* Poison the route */ 1894 new = rt->rt_spares[0]; 1895 new.rts_metric = HOPCNT_INFINITY; 1896 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0); 1897 rtswitch(rt, 0); 1898 } 1899 1900 1901 /* Junk a RS_NET_SYN or RS_LOCAL route, 1902 * unless it is needed by another interface. 1903 */ 1904 void 1905 rtbad_sub(struct rt_entry *rt) 1906 { 1907 struct interface *ifp, *ifp1; 1908 struct intnet *intnetp; 1909 u_int state; 1910 1911 1912 ifp1 = NULL; 1913 state = 0; 1914 1915 if (rt->rt_state & RS_LOCAL) { 1916 /* Is this the route through loopback for the interface? 1917 * If so, see if it is used by any other interfaces, such 1918 * as a point-to-point interface with the same local address. 1919 */ 1920 LIST_FOREACH(ifp, &ifnet, int_list) { 1921 /* Retain it if another interface needs it. 1922 */ 1923 if (ifp->int_addr == rt->rt_ifp->int_addr) { 1924 state |= RS_LOCAL; 1925 ifp1 = ifp; 1926 break; 1927 } 1928 } 1929 1930 } 1931 1932 if (!(state & RS_LOCAL)) { 1933 /* Retain RIPv1 logical network route if there is another 1934 * interface that justifies it. 1935 */ 1936 if (rt->rt_state & RS_NET_SYN) { 1937 LIST_FOREACH(ifp, &ifnet, int_list) { 1938 if ((ifp->int_state & IS_NEED_NET_SYN) 1939 && rt->rt_mask == ifp->int_std_mask 1940 && rt->rt_dst == ifp->int_std_addr) { 1941 state |= RS_NET_SYN; 1942 ifp1 = ifp; 1943 break; 1944 } 1945 } 1946 } 1947 1948 /* or if there is an authority route that needs it. */ 1949 for (intnetp = intnets; 1950 intnetp != NULL; 1951 intnetp = intnetp->intnet_next) { 1952 if (intnetp->intnet_addr == rt->rt_dst 1953 && intnetp->intnet_mask == rt->rt_mask) { 1954 state |= (RS_NET_SYN | RS_NET_INT); 1955 break; 1956 } 1957 } 1958 } 1959 1960 if (ifp1 != NULL || (state & RS_NET_SYN)) { 1961 struct rt_spare new = rt->rt_spares[0]; 1962 new.rts_ifp = ifp1; 1963 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state), 1964 &new, 0); 1965 } else { 1966 rtbad(rt); 1967 } 1968 } 1969 1970 1971 /* Called while walking the table looking for sick interfaces 1972 * or after a time change. 1973 */ 1974 /* ARGSUSED */ 1975 int 1976 walk_bad(struct radix_node *rn, 1977 struct walkarg *argp UNUSED) 1978 { 1979 #define RT ((struct rt_entry *)rn) 1980 struct rt_spare *rts; 1981 int i; 1982 1983 1984 /* fix any spare routes through the interface 1985 */ 1986 rts = RT->rt_spares; 1987 for (i = NUM_SPARES; i != 1; i--) { 1988 rts++; 1989 if (rts->rts_metric < HOPCNT_INFINITY 1990 && (rts->rts_ifp == NULL 1991 || (rts->rts_ifp->int_state & IS_BROKE))) 1992 rts_delete(RT, rts); 1993 } 1994 1995 /* Deal with the main route 1996 */ 1997 /* finished if it has been handled before or if its interface is ok 1998 */ 1999 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE)) 2000 return 0; 2001 2002 /* Bad routes for other than interfaces are easy. 2003 */ 2004 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) { 2005 rtbad(RT); 2006 return 0; 2007 } 2008 2009 rtbad_sub(RT); 2010 return 0; 2011 #undef RT 2012 } 2013 2014 2015 /* Check the age of an individual route. 2016 */ 2017 /* ARGSUSED */ 2018 static int 2019 walk_age(struct radix_node *rn, 2020 struct walkarg *argp UNUSED) 2021 { 2022 #define RT ((struct rt_entry *)rn) 2023 struct interface *ifp; 2024 struct rt_spare *rts; 2025 int i; 2026 2027 2028 /* age all of the spare routes, including the primary route 2029 * currently in use 2030 */ 2031 rts = RT->rt_spares; 2032 for (i = NUM_SPARES; i != 0; i--, rts++) { 2033 2034 ifp = rts->rts_ifp; 2035 if (i == NUM_SPARES) { 2036 if (!AGE_RT(RT->rt_state, ifp)) { 2037 /* Keep various things from deciding ageless 2038 * routes are stale 2039 */ 2040 rts->rts_time = now.tv_sec; 2041 continue; 2042 } 2043 2044 /* forget RIP routes after RIP has been turned off. 2045 */ 2046 if (rip_sock < 0) { 2047 rtdelete(RT); 2048 return 0; 2049 } 2050 } 2051 2052 /* age failing routes 2053 */ 2054 if (age_bad_gate == rts->rts_gate 2055 && rts->rts_time >= now_stale) { 2056 rts->rts_time -= SUPPLY_INTERVAL; 2057 } 2058 2059 /* trash the spare routes when they go bad */ 2060 if (rts->rts_metric < HOPCNT_INFINITY 2061 && now_garbage > rts->rts_time 2062 && i != NUM_SPARES) 2063 rts_delete(RT, rts); 2064 } 2065 2066 2067 /* finished if the active route is still fresh */ 2068 if (now_stale <= RT->rt_time) 2069 return 0; 2070 2071 /* try to switch to an alternative */ 2072 rtswitch(RT, 0); 2073 2074 /* Delete a dead route after it has been publicly mourned. */ 2075 if (now_garbage > RT->rt_time) { 2076 rtdelete(RT); 2077 return 0; 2078 } 2079 2080 /* Start poisoning a bad route before deleting it. */ 2081 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) { 2082 struct rt_spare new = RT->rt_spares[0]; 2083 new.rts_metric = HOPCNT_INFINITY; 2084 rtchange(RT, RT->rt_state, &new, 0); 2085 } 2086 return 0; 2087 } 2088 2089 2090 /* Watch for dead routes and interfaces. 2091 */ 2092 void 2093 age(naddr bad_gate) 2094 { 2095 struct interface *ifp; 2096 int need_query = 0; 2097 2098 /* If not listening to RIP, there is no need to age the routes in 2099 * the table. 2100 */ 2101 age_timer.tv_sec = (now.tv_sec 2102 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL)); 2103 2104 /* Check for dead IS_REMOTE interfaces by timing their 2105 * transmissions. 2106 */ 2107 LIST_FOREACH(ifp, &ifnet, int_list) { 2108 if (!(ifp->int_state & IS_REMOTE)) 2109 continue; 2110 2111 /* ignore unreachable remote interfaces */ 2112 if (!check_remote(ifp)) 2113 continue; 2114 2115 /* Restore remote interface that has become reachable 2116 */ 2117 if (ifp->int_state & IS_BROKE) 2118 if_ok(ifp, "remote "); 2119 2120 if (ifp->int_act_time != NEVER 2121 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) { 2122 msglog("remote interface %s to %s timed out after" 2123 " %ld:%ld", 2124 ifp->int_name, 2125 naddr_ntoa(ifp->int_dstaddr), 2126 (long)(now.tv_sec - ifp->int_act_time)/60, 2127 (long)(now.tv_sec - ifp->int_act_time)%60); 2128 if_sick(ifp); 2129 } 2130 2131 /* If we have not heard from the other router 2132 * recently, ask it. 2133 */ 2134 if (now.tv_sec >= ifp->int_query_time) { 2135 ifp->int_query_time = NEVER; 2136 need_query = 1; 2137 } 2138 } 2139 2140 /* Age routes. */ 2141 age_bad_gate = bad_gate; 2142 (void)rn_walktree(rhead, walk_age, 0); 2143 2144 /* delete old redirected routes to keep the kernel table small 2145 * and prevent blackholes 2146 */ 2147 del_redirects(bad_gate, now.tv_sec-STALE_TIME); 2148 2149 /* Update the kernel routing table. */ 2150 fix_kern(); 2151 2152 /* poke reticent remote gateways */ 2153 if (need_query) 2154 rip_query(); 2155 } 2156