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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgment: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD$ 34 */ 35 36 #include "defs.h" 37 38 #if !defined(sgi) && !defined(__NetBSD__) 39 static char sccsid[] __attribute__((unused)) = "@(#)tables.c 8.1 (Berkeley) 6/5/93"; 40 #elif defined(__NetBSD__) 41 __RCSID("$NetBSD$"); 42 #endif 43 #ident "$FreeBSD$" 44 45 static struct rt_spare *rts_better(struct rt_entry *); 46 static struct rt_spare rts_empty = {0,0,0,HOPCNT_INFINITY,0,0,0}; 47 static void set_need_flash(void); 48 #ifdef _HAVE_SIN_LEN 49 static void masktrim(struct sockaddr_in *ap); 50 #else 51 static void masktrim(struct sockaddr_in_new *ap); 52 #endif 53 54 55 struct radix_node_head *rhead; /* root of the radix tree */ 56 57 int need_flash = 1; /* flash update needed 58 * start =1 to suppress the 1st 59 */ 60 61 struct timeval age_timer; /* next check of old routes */ 62 struct timeval need_kern = { /* need to update kernel table */ 63 EPOCH+MIN_WAITTIME-1 64 }; 65 66 int stopint; 67 68 int total_routes; 69 70 /* zap any old routes through this gateway */ 71 naddr age_bad_gate; 72 73 74 /* It is desirable to "aggregate" routes, to combine differing routes of 75 * the same metric and next hop into a common route with a smaller netmask 76 * or to suppress redundant routes, routes that add no information to 77 * routes with smaller netmasks. 78 * 79 * A route is redundant if and only if any and all routes with smaller 80 * but matching netmasks and nets are the same. Since routes are 81 * kept sorted in the radix tree, redundant routes always come second. 82 * 83 * There are two kinds of aggregations. First, two routes of the same bit 84 * mask and differing only in the least significant bit of the network 85 * number can be combined into a single route with a coarser mask. 86 * 87 * Second, a route can be suppressed in favor of another route with a more 88 * coarse mask provided no incompatible routes with intermediate masks 89 * are present. The second kind of aggregation involves suppressing routes. 90 * A route must not be suppressed if an incompatible route exists with 91 * an intermediate mask, since the suppressed route would be covered 92 * by the intermediate. 93 * 94 * This code relies on the radix tree walk encountering routes 95 * sorted first by address, with the smallest address first. 96 */ 97 98 struct ag_info ag_slots[NUM_AG_SLOTS], *ag_avail, *ag_corsest, *ag_finest; 99 100 /* #define DEBUG_AG */ 101 #ifdef DEBUG_AG 102 #define CHECK_AG() {int acnt = 0; struct ag_info *cag; \ 103 for (cag = ag_avail; cag != 0; cag = cag->ag_fine) \ 104 acnt++; \ 105 for (cag = ag_corsest; cag != 0; cag = cag->ag_fine) \ 106 acnt++; \ 107 if (acnt != NUM_AG_SLOTS) { \ 108 (void)fflush(stderr); \ 109 abort(); \ 110 } \ 111 } 112 #else 113 #define CHECK_AG() 114 #endif 115 116 117 /* Output the contents of an aggregation table slot. 118 * This function must always be immediately followed with the deletion 119 * of the target slot. 120 */ 121 static void 122 ag_out(struct ag_info *ag, 123 void (*out)(struct ag_info *)) 124 { 125 struct ag_info *ag_cors; 126 naddr bit; 127 128 129 /* Forget it if this route should not be output for split-horizon. */ 130 if (ag->ag_state & AGS_SPLIT_HZ) 131 return; 132 133 /* If we output both the even and odd twins, then the immediate parent, 134 * if it is present, is redundant, unless the parent manages to 135 * aggregate into something coarser. 136 * On successive calls, this code detects the even and odd twins, 137 * and marks the parent. 138 * 139 * Note that the order in which the radix tree code emits routes 140 * ensures that the twins are seen before the parent is emitted. 141 */ 142 ag_cors = ag->ag_cors; 143 if (ag_cors != 0 144 && ag_cors->ag_mask == ag->ag_mask<<1 145 && ag_cors->ag_dst_h == (ag->ag_dst_h & ag_cors->ag_mask)) { 146 ag_cors->ag_state |= ((ag_cors->ag_dst_h == ag->ag_dst_h) 147 ? AGS_REDUN0 148 : AGS_REDUN1); 149 } 150 151 /* Skip it if this route is itself redundant. 152 * 153 * It is ok to change the contents of the slot here, since it is 154 * always deleted next. 155 */ 156 if (ag->ag_state & AGS_REDUN0) { 157 if (ag->ag_state & AGS_REDUN1) 158 return; /* quit if fully redundant */ 159 /* make it finer if it is half-redundant */ 160 bit = (-ag->ag_mask) >> 1; 161 ag->ag_dst_h |= bit; 162 ag->ag_mask |= bit; 163 164 } else if (ag->ag_state & AGS_REDUN1) { 165 /* make it finer if it is half-redundant */ 166 bit = (-ag->ag_mask) >> 1; 167 ag->ag_mask |= bit; 168 } 169 out(ag); 170 } 171 172 173 static void 174 ag_del(struct ag_info *ag) 175 { 176 CHECK_AG(); 177 178 if (ag->ag_cors == 0) 179 ag_corsest = ag->ag_fine; 180 else 181 ag->ag_cors->ag_fine = ag->ag_fine; 182 183 if (ag->ag_fine == 0) 184 ag_finest = ag->ag_cors; 185 else 186 ag->ag_fine->ag_cors = ag->ag_cors; 187 188 ag->ag_fine = ag_avail; 189 ag_avail = ag; 190 191 CHECK_AG(); 192 } 193 194 195 /* Flush routes waiting for aggregation. 196 * This must not suppress a route unless it is known that among all 197 * routes with coarser masks that match it, the one with the longest 198 * mask is appropriate. This is ensured by scanning the routes 199 * in lexical order, and with the most restrictive mask first 200 * among routes to the same destination. 201 */ 202 void 203 ag_flush(naddr lim_dst_h, /* flush routes to here */ 204 naddr lim_mask, /* matching this mask */ 205 void (*out)(struct ag_info *)) 206 { 207 struct ag_info *ag, *ag_cors; 208 naddr dst_h; 209 210 211 for (ag = ag_finest; 212 ag != 0 && ag->ag_mask >= lim_mask; 213 ag = ag_cors) { 214 ag_cors = ag->ag_cors; 215 216 /* work on only the specified routes */ 217 dst_h = ag->ag_dst_h; 218 if ((dst_h & lim_mask) != lim_dst_h) 219 continue; 220 221 if (!(ag->ag_state & AGS_SUPPRESS)) 222 ag_out(ag, out); 223 224 else for ( ; ; ag_cors = ag_cors->ag_cors) { 225 /* Look for a route that can suppress the 226 * current route */ 227 if (ag_cors == 0) { 228 /* failed, so output it and look for 229 * another route to work on 230 */ 231 ag_out(ag, out); 232 break; 233 } 234 235 if ((dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h) { 236 /* We found a route with a coarser mask that 237 * aggregates the current target. 238 * 239 * If it has a different next hop, it 240 * cannot replace the target, so output 241 * the target. 242 */ 243 if (ag->ag_gate != ag_cors->ag_gate 244 && !(ag->ag_state & AGS_FINE_GATE) 245 && !(ag_cors->ag_state & AGS_CORS_GATE)) { 246 ag_out(ag, out); 247 break; 248 } 249 250 /* If the coarse route has a good enough 251 * metric, it suppresses the target. 252 * If the suppressed target was redundant, 253 * then mark the suppressor redundant. 254 */ 255 if (ag_cors->ag_pref <= ag->ag_pref) { 256 if (ag_cors->ag_seqno > ag->ag_seqno) 257 ag_cors->ag_seqno = ag->ag_seqno; 258 if (AG_IS_REDUN(ag->ag_state) 259 && ag_cors->ag_mask==ag->ag_mask<<1) { 260 if (ag_cors->ag_dst_h == dst_h) 261 ag_cors->ag_state |= AGS_REDUN0; 262 else 263 ag_cors->ag_state |= AGS_REDUN1; 264 } 265 if (ag->ag_tag != ag_cors->ag_tag) 266 ag_cors->ag_tag = 0; 267 if (ag->ag_nhop != ag_cors->ag_nhop) 268 ag_cors->ag_nhop = 0; 269 break; 270 } 271 } 272 } 273 274 /* That route has either been output or suppressed */ 275 ag_cors = ag->ag_cors; 276 ag_del(ag); 277 } 278 279 CHECK_AG(); 280 } 281 282 283 /* Try to aggregate a route with previous routes. 284 */ 285 void 286 ag_check(naddr dst, 287 naddr mask, 288 naddr gate, 289 naddr nhop, 290 char metric, 291 char pref, 292 u_int seqno, 293 u_short tag, 294 u_short state, 295 void (*out)(struct ag_info *)) /* output using this */ 296 { 297 struct ag_info *ag, *nag, *ag_cors; 298 naddr xaddr; 299 int x; 300 301 NTOHL(dst); 302 303 /* Punt non-contiguous subnet masks. 304 * 305 * (X & -X) contains a single bit if and only if X is a power of 2. 306 * (X + (X & -X)) == 0 if and only if X is a power of 2. 307 */ 308 if ((mask & -mask) + mask != 0) { 309 struct ag_info nc_ag; 310 311 nc_ag.ag_dst_h = dst; 312 nc_ag.ag_mask = mask; 313 nc_ag.ag_gate = gate; 314 nc_ag.ag_nhop = nhop; 315 nc_ag.ag_metric = metric; 316 nc_ag.ag_pref = pref; 317 nc_ag.ag_tag = tag; 318 nc_ag.ag_state = state; 319 nc_ag.ag_seqno = seqno; 320 out(&nc_ag); 321 return; 322 } 323 324 /* Search for the right slot in the aggregation table. 325 */ 326 ag_cors = 0; 327 ag = ag_corsest; 328 while (ag != 0) { 329 if (ag->ag_mask >= mask) 330 break; 331 332 /* Suppress old routes (i.e. combine with compatible routes 333 * with coarser masks) as we look for the right slot in the 334 * aggregation table for the new route. 335 * A route to an address less than the current destination 336 * will not be affected by the current route or any route 337 * seen hereafter. That means it is safe to suppress it. 338 * This check keeps poor routes (e.g. with large hop counts) 339 * from preventing suppression of finer routes. 340 */ 341 if (ag_cors != 0 342 && ag->ag_dst_h < dst 343 && (ag->ag_state & AGS_SUPPRESS) 344 && ag_cors->ag_pref <= ag->ag_pref 345 && (ag->ag_dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h 346 && (ag_cors->ag_gate == ag->ag_gate 347 || (ag->ag_state & AGS_FINE_GATE) 348 || (ag_cors->ag_state & AGS_CORS_GATE))) { 349 if (ag_cors->ag_seqno > ag->ag_seqno) 350 ag_cors->ag_seqno = ag->ag_seqno; 351 /* If the suppressed target was redundant, 352 * then mark the suppressor redundant. 353 */ 354 if (AG_IS_REDUN(ag->ag_state) 355 && ag_cors->ag_mask==ag->ag_mask<<1) { 356 if (ag_cors->ag_dst_h == dst) 357 ag_cors->ag_state |= AGS_REDUN0; 358 else 359 ag_cors->ag_state |= AGS_REDUN1; 360 } 361 if (ag->ag_tag != ag_cors->ag_tag) 362 ag_cors->ag_tag = 0; 363 if (ag->ag_nhop != ag_cors->ag_nhop) 364 ag_cors->ag_nhop = 0; 365 ag_del(ag); 366 CHECK_AG(); 367 } else { 368 ag_cors = ag; 369 } 370 ag = ag_cors->ag_fine; 371 } 372 373 /* If we find the even/odd twin of the new route, and if the 374 * masks and so forth are equal, we can aggregate them. 375 * We can probably promote one of the pair. 376 * 377 * Since the routes are encountered in lexical order, 378 * the new route must be odd. However, the second or later 379 * times around this loop, it could be the even twin promoted 380 * from the even/odd pair of twins of the finer route. 381 */ 382 while (ag != 0 383 && ag->ag_mask == mask 384 && ((ag->ag_dst_h ^ dst) & (mask<<1)) == 0) { 385 386 /* Here we know the target route and the route in the current 387 * slot have the same netmasks and differ by at most the 388 * last bit. They are either for the same destination, or 389 * for an even/odd pair of destinations. 390 */ 391 if (ag->ag_dst_h == dst) { 392 /* We have two routes to the same destination. 393 * Routes are encountered in lexical order, so a 394 * route is never promoted until the parent route is 395 * already present. So we know that the new route is 396 * a promoted (or aggregated) pair and the route 397 * already in the slot is the explicit route. 398 * 399 * Prefer the best route if their metrics differ, 400 * or the aggregated one if not, following a sort 401 * of longest-match rule. 402 */ 403 if (pref <= ag->ag_pref) { 404 ag->ag_gate = gate; 405 ag->ag_nhop = nhop; 406 ag->ag_tag = tag; 407 ag->ag_metric = metric; 408 ag->ag_pref = pref; 409 x = ag->ag_state; 410 ag->ag_state = state; 411 state = x; 412 } 413 414 /* The sequence number controls flash updating, 415 * and should be the smaller of the two. 416 */ 417 if (ag->ag_seqno > seqno) 418 ag->ag_seqno = seqno; 419 420 /* Some bits are set if they are set on either route, 421 * except when the route is for an interface. 422 */ 423 if (!(ag->ag_state & AGS_IF)) 424 ag->ag_state |= (state & (AGS_AGGREGATE_EITHER 425 | AGS_REDUN0 426 | AGS_REDUN1)); 427 return; 428 } 429 430 /* If one of the routes can be promoted and the other can 431 * be suppressed, it may be possible to combine them or 432 * worthwhile to promote one. 433 * 434 * Any route that can be promoted is always 435 * marked to be eligible to be suppressed. 436 */ 437 if (!((state & AGS_AGGREGATE) 438 && (ag->ag_state & AGS_SUPPRESS)) 439 && !((ag->ag_state & AGS_AGGREGATE) 440 && (state & AGS_SUPPRESS))) 441 break; 442 443 /* A pair of even/odd twin routes can be combined 444 * if either is redundant, or if they are via the 445 * same gateway and have the same metric. 446 */ 447 if (AG_IS_REDUN(ag->ag_state) 448 || AG_IS_REDUN(state) 449 || (ag->ag_gate == gate 450 && ag->ag_pref == pref 451 && (state & ag->ag_state & AGS_AGGREGATE) != 0)) { 452 453 /* We have both the even and odd pairs. 454 * Since the routes are encountered in order, 455 * the route in the slot must be the even twin. 456 * 457 * Combine and promote (aggregate) the pair of routes. 458 */ 459 if (seqno > ag->ag_seqno) 460 seqno = ag->ag_seqno; 461 if (!AG_IS_REDUN(state)) 462 state &= ~AGS_REDUN1; 463 if (AG_IS_REDUN(ag->ag_state)) 464 state |= AGS_REDUN0; 465 else 466 state &= ~AGS_REDUN0; 467 state |= (ag->ag_state & AGS_AGGREGATE_EITHER); 468 if (ag->ag_tag != tag) 469 tag = 0; 470 if (ag->ag_nhop != nhop) 471 nhop = 0; 472 473 /* Get rid of the even twin that was already 474 * in the slot. 475 */ 476 ag_del(ag); 477 478 } else if (ag->ag_pref >= pref 479 && (ag->ag_state & AGS_AGGREGATE)) { 480 /* If we cannot combine the pair, maybe the route 481 * with the worse metric can be promoted. 482 * 483 * Promote the old, even twin, by giving its slot 484 * in the table to the new, odd twin. 485 */ 486 ag->ag_dst_h = dst; 487 488 xaddr = ag->ag_gate; 489 ag->ag_gate = gate; 490 gate = xaddr; 491 492 xaddr = ag->ag_nhop; 493 ag->ag_nhop = nhop; 494 nhop = xaddr; 495 496 x = ag->ag_tag; 497 ag->ag_tag = tag; 498 tag = x; 499 500 /* The promoted route is even-redundant only if the 501 * even twin was fully redundant. It is not 502 * odd-redundant because the odd-twin will still be 503 * in the table. 504 */ 505 x = ag->ag_state; 506 if (!AG_IS_REDUN(x)) 507 x &= ~AGS_REDUN0; 508 x &= ~AGS_REDUN1; 509 ag->ag_state = state; 510 state = x; 511 512 x = ag->ag_metric; 513 ag->ag_metric = metric; 514 metric = x; 515 516 x = ag->ag_pref; 517 ag->ag_pref = pref; 518 pref = x; 519 520 /* take the newest sequence number */ 521 if (seqno >= ag->ag_seqno) 522 seqno = ag->ag_seqno; 523 else 524 ag->ag_seqno = seqno; 525 526 } else { 527 if (!(state & AGS_AGGREGATE)) 528 break; /* cannot promote either twin */ 529 530 /* Promote the new, odd twin by shaving its 531 * mask and address. 532 * The promoted route is odd-redundant only if the 533 * odd twin was fully redundant. It is not 534 * even-redundant because the even twin is still in 535 * the table. 536 */ 537 if (!AG_IS_REDUN(state)) 538 state &= ~AGS_REDUN1; 539 state &= ~AGS_REDUN0; 540 if (seqno > ag->ag_seqno) 541 seqno = ag->ag_seqno; 542 else 543 ag->ag_seqno = seqno; 544 } 545 546 mask <<= 1; 547 dst &= mask; 548 549 if (ag_cors == 0) { 550 ag = ag_corsest; 551 break; 552 } 553 ag = ag_cors; 554 ag_cors = ag->ag_cors; 555 } 556 557 /* When we can no longer promote and combine routes, 558 * flush the old route in the target slot. Also flush 559 * any finer routes that we know will never be aggregated by 560 * the new route. 561 * 562 * In case we moved toward coarser masks, 563 * get back where we belong 564 */ 565 if (ag != 0 566 && ag->ag_mask < mask) { 567 ag_cors = ag; 568 ag = ag->ag_fine; 569 } 570 571 /* Empty the target slot 572 */ 573 if (ag != 0 && ag->ag_mask == mask) { 574 ag_flush(ag->ag_dst_h, ag->ag_mask, out); 575 ag = (ag_cors == 0) ? ag_corsest : ag_cors->ag_fine; 576 } 577 578 #ifdef DEBUG_AG 579 (void)fflush(stderr); 580 if (ag == 0 && ag_cors != ag_finest) 581 abort(); 582 if (ag_cors == 0 && ag != ag_corsest) 583 abort(); 584 if (ag != 0 && ag->ag_cors != ag_cors) 585 abort(); 586 if (ag_cors != 0 && ag_cors->ag_fine != ag) 587 abort(); 588 CHECK_AG(); 589 #endif 590 591 /* Save the new route on the end of the table. 592 */ 593 nag = ag_avail; 594 ag_avail = nag->ag_fine; 595 596 nag->ag_dst_h = dst; 597 nag->ag_mask = mask; 598 nag->ag_gate = gate; 599 nag->ag_nhop = nhop; 600 nag->ag_metric = metric; 601 nag->ag_pref = pref; 602 nag->ag_tag = tag; 603 nag->ag_state = state; 604 nag->ag_seqno = seqno; 605 606 nag->ag_fine = ag; 607 if (ag != 0) 608 ag->ag_cors = nag; 609 else 610 ag_finest = nag; 611 nag->ag_cors = ag_cors; 612 if (ag_cors == 0) 613 ag_corsest = nag; 614 else 615 ag_cors->ag_fine = nag; 616 CHECK_AG(); 617 } 618 619 620 #define NAME0_LEN 14 621 static const char * 622 rtm_type_name(u_char type) 623 { 624 static const char *rtm_types[] = { 625 "RTM_ADD", 626 "RTM_DELETE", 627 "RTM_CHANGE", 628 "RTM_GET", 629 "RTM_LOSING", 630 "RTM_REDIRECT", 631 "RTM_MISS", 632 "RTM_LOCK", 633 "RTM_OLDADD", 634 "RTM_OLDDEL", 635 "RTM_RESOLVE", 636 "RTM_NEWADDR", 637 "RTM_DELADDR", 638 "RTM_IFINFO", 639 "RTM_NEWMADDR", 640 "RTM_DELMADDR" 641 }; 642 static char name0[NAME0_LEN]; 643 644 645 if (type > sizeof(rtm_types)/sizeof(rtm_types[0]) 646 || type == 0) { 647 snprintf(name0, NAME0_LEN, "RTM type %#x", type); 648 return name0; 649 } else { 650 return rtm_types[type-1]; 651 } 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 */ 659 void 660 #ifdef _HAVE_SIN_LEN 661 masktrim(struct sockaddr_in *ap) 662 #else 663 masktrim(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 */ 681 static void 682 rtioctl(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 702 703 again: 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] 766 static 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]; 787 788 789 static struct khash* 790 kern_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 } 802 803 804 static struct khash* 805 kern_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 */ 829 static void 830 kern_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 */ 858 static void 859 kern_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 */ 888 static void 889 rtm_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 */ 992 static void 993 rtm_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 */ 1013 static int 1014 get_info_gate(struct sockaddr **sap, 1015 struct sockaddr_in *sin) 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 sin->sin_addr.s_addr = ifp->int_addr; 1032 #ifdef _HAVE_SA_LEN 1033 sin->sin_len = sizeof(*sin); 1034 #endif 1035 sin->sin_family = AF_INET; 1036 *sap = (struct sockaddr*)sin; 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 */ 1045 void 1046 flush_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 /* ignore multicast addresses 1118 */ 1119 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) 1120 continue; 1121 1122 if (!get_info_gate(&INFO_GATE(&info), &gate_sin)) 1123 continue; 1124 1125 /* Note static routes and interface routes, and also 1126 * preload the image of the kernel table so that 1127 * we can later clean it, as well as avoid making 1128 * unneeded changes. Keep the old kernel routes for a 1129 * few seconds to allow a RIP or router-discovery 1130 * response to be heard. 1131 */ 1132 rtm_add(rtm,&info,MIN_WAITTIME); 1133 } 1134 1135 for (i = 0; i < KHASH_SIZE; i++) { 1136 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1137 if (k->k_state & KS_CHECK) { 1138 msglog("%s --> %s disappeared from kernel", 1139 addrname(k->k_dst, k->k_mask, 0), 1140 naddr_ntoa(k->k_gate)); 1141 del_static(k->k_dst, k->k_mask, k->k_gate, 1); 1142 } 1143 } 1144 } 1145 } 1146 1147 1148 /* Listen to announcements from the kernel 1149 */ 1150 void 1151 read_rt(void) 1152 { 1153 long cc; 1154 struct interface *ifp; 1155 struct sockaddr_in gate_sin; 1156 naddr mask, gate; 1157 union { 1158 struct { 1159 struct rt_msghdr rtm; 1160 struct sockaddr addrs[RTAX_MAX]; 1161 } r; 1162 struct if_msghdr ifm; 1163 } m; 1164 char str[100], *strp; 1165 struct rt_addrinfo info; 1166 1167 1168 for (;;) { 1169 cc = read(rt_sock, &m, sizeof(m)); 1170 if (cc <= 0) { 1171 if (cc < 0 && errno != EWOULDBLOCK) 1172 LOGERR("read(rt_sock)"); 1173 return; 1174 } 1175 1176 if (m.r.rtm.rtm_version != RTM_VERSION) { 1177 msglog("bogus routing message version %d", 1178 m.r.rtm.rtm_version); 1179 continue; 1180 } 1181 1182 /* Ignore our own results. 1183 */ 1184 if (m.r.rtm.rtm_type <= RTM_CHANGE 1185 && m.r.rtm.rtm_pid == mypid) { 1186 static int complained = 0; 1187 if (!complained) { 1188 msglog("receiving our own change messages"); 1189 complained = 1; 1190 } 1191 continue; 1192 } 1193 1194 if (m.r.rtm.rtm_type == RTM_IFINFO 1195 || m.r.rtm.rtm_type == RTM_NEWADDR 1196 || m.r.rtm.rtm_type == RTM_DELADDR) { 1197 ifp = ifwithindex(m.ifm.ifm_index, 1198 m.r.rtm.rtm_type != RTM_DELADDR); 1199 if (ifp == 0) 1200 trace_act("note %s with flags %#x" 1201 " for unknown interface index #%d", 1202 rtm_type_name(m.r.rtm.rtm_type), 1203 m.ifm.ifm_flags, 1204 m.ifm.ifm_index); 1205 else 1206 trace_act("note %s with flags %#x for %s", 1207 rtm_type_name(m.r.rtm.rtm_type), 1208 m.ifm.ifm_flags, 1209 ifp->int_name); 1210 1211 /* After being informed of a change to an interface, 1212 * check them all now if the check would otherwise 1213 * be a long time from now, if the interface is 1214 * not known, or if the interface has been turned 1215 * off or on. 1216 */ 1217 if (ifinit_timer.tv_sec-now.tv_sec>=CHECK_BAD_INTERVAL 1218 || ifp == 0 1219 || ((ifp->int_if_flags ^ m.ifm.ifm_flags) 1220 & IFF_UP) != 0) 1221 ifinit_timer.tv_sec = now.tv_sec; 1222 continue; 1223 } 1224 1225 strcpy(str, rtm_type_name(m.r.rtm.rtm_type)); 1226 strp = &str[strlen(str)]; 1227 if (m.r.rtm.rtm_type <= RTM_CHANGE) 1228 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid); 1229 1230 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX], 1231 m.r.rtm.rtm_addrs); 1232 1233 if (INFO_DST(&info) == 0) { 1234 trace_act("ignore %s without dst", str); 1235 continue; 1236 } 1237 1238 if (INFO_DST(&info)->sa_family != AF_INET) { 1239 trace_act("ignore %s for AF %d", str, 1240 INFO_DST(&info)->sa_family); 1241 continue; 1242 } 1243 1244 mask = ((INFO_MASK(&info) != 0) 1245 ? ntohl(S_ADDR(INFO_MASK(&info))) 1246 : (m.r.rtm.rtm_flags & RTF_HOST) 1247 ? HOST_MASK 1248 : std_mask(S_ADDR(INFO_DST(&info)))); 1249 1250 strp += sprintf(strp, ": %s", 1251 addrname(S_ADDR(INFO_DST(&info)), mask, 0)); 1252 1253 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) { 1254 trace_act("ignore multicast %s", str); 1255 continue; 1256 } 1257 1258 if (m.r.rtm.rtm_flags & RTF_LLINFO) { 1259 trace_act("ignore ARP %s", str); 1260 continue; 1261 } 1262 1263 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) { 1264 gate = S_ADDR(INFO_GATE(&info)); 1265 strp += sprintf(strp, " --> %s", naddr_ntoa(gate)); 1266 } else { 1267 gate = 0; 1268 } 1269 1270 if (INFO_AUTHOR(&info) != 0) 1271 strp += sprintf(strp, " by authority of %s", 1272 saddr_ntoa(INFO_AUTHOR(&info))); 1273 1274 switch (m.r.rtm.rtm_type) { 1275 case RTM_ADD: 1276 case RTM_CHANGE: 1277 case RTM_REDIRECT: 1278 if (m.r.rtm.rtm_errno != 0) { 1279 trace_act("ignore %s with \"%s\" error", 1280 str, strerror(m.r.rtm.rtm_errno)); 1281 } else { 1282 trace_act("%s", str); 1283 rtm_add(&m.r.rtm,&info,0); 1284 } 1285 break; 1286 1287 case RTM_DELETE: 1288 if (m.r.rtm.rtm_errno != 0 1289 && m.r.rtm.rtm_errno != ESRCH) { 1290 trace_act("ignore %s with \"%s\" error", 1291 str, strerror(m.r.rtm.rtm_errno)); 1292 } else { 1293 trace_act("%s", str); 1294 del_static(S_ADDR(INFO_DST(&info)), mask, 1295 gate, 1); 1296 } 1297 break; 1298 1299 case RTM_LOSING: 1300 trace_act("%s", str); 1301 rtm_lose(&m.r.rtm,&info); 1302 break; 1303 1304 default: 1305 trace_act("ignore %s", str); 1306 break; 1307 } 1308 } 1309 } 1310 1311 1312 /* after aggregating, note routes that belong in the kernel 1313 */ 1314 static void 1315 kern_out(struct ag_info *ag) 1316 { 1317 struct khash *k; 1318 1319 1320 /* Do not install bad routes if they are not already present. 1321 * This includes routes that had RS_NET_SYN for interfaces that 1322 * recently died. 1323 */ 1324 if (ag->ag_metric == HOPCNT_INFINITY) { 1325 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0); 1326 if (k == 0) 1327 return; 1328 } else { 1329 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask); 1330 } 1331 1332 if (k->k_state & KS_NEW) { 1333 /* will need to add new entry to the kernel table */ 1334 k->k_state = KS_ADD; 1335 if (ag->ag_state & AGS_GATEWAY) 1336 k->k_state |= KS_GATEWAY; 1337 k->k_gate = ag->ag_gate; 1338 k->k_metric = ag->ag_metric; 1339 return; 1340 } 1341 1342 if (k->k_state & KS_STATIC) 1343 return; 1344 1345 /* modify existing kernel entry if necessary */ 1346 if (k->k_gate != ag->ag_gate 1347 || k->k_metric != ag->ag_metric) { 1348 /* Must delete bad interface routes etc. to change them. */ 1349 if (k->k_metric == HOPCNT_INFINITY) 1350 k->k_state |= KS_DEL_ADD; 1351 k->k_gate = ag->ag_gate; 1352 k->k_metric = ag->ag_metric; 1353 k->k_state |= KS_CHANGE; 1354 } 1355 1356 /* If the daemon thinks the route should exist, forget 1357 * about any redirections. 1358 * If the daemon thinks the route should exist, eventually 1359 * override manual intervention by the operator. 1360 */ 1361 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) { 1362 k->k_state &= ~KS_DYNAMIC; 1363 k->k_state |= (KS_ADD | KS_DEL_ADD); 1364 } 1365 1366 if ((k->k_state & KS_GATEWAY) 1367 && !(ag->ag_state & AGS_GATEWAY)) { 1368 k->k_state &= ~KS_GATEWAY; 1369 k->k_state |= (KS_ADD | KS_DEL_ADD); 1370 } else if (!(k->k_state & KS_GATEWAY) 1371 && (ag->ag_state & AGS_GATEWAY)) { 1372 k->k_state |= KS_GATEWAY; 1373 k->k_state |= (KS_ADD | KS_DEL_ADD); 1374 } 1375 1376 /* Deleting-and-adding is necessary to change aspects of a route. 1377 * Just delete instead of deleting and then adding a bad route. 1378 * Otherwise, we want to keep the route in the kernel. 1379 */ 1380 if (k->k_metric == HOPCNT_INFINITY 1381 && (k->k_state & KS_DEL_ADD)) 1382 k->k_state |= KS_DELETE; 1383 else 1384 k->k_state &= ~KS_DELETE; 1385 #undef RT 1386 } 1387 1388 1389 /* ARGSUSED */ 1390 static int 1391 walk_kern(struct radix_node *rn, 1392 struct walkarg *argp UNUSED) 1393 { 1394 #define RT ((struct rt_entry *)rn) 1395 char metric, pref; 1396 u_int ags = 0; 1397 1398 1399 /* Do not install synthetic routes */ 1400 if (RT->rt_state & RS_NET_SYN) 1401 return 0; 1402 1403 if (!(RT->rt_state & RS_IF)) { 1404 /* This is an ordinary route, not for an interface. 1405 */ 1406 1407 /* aggregate, ordinary good routes without regard to 1408 * their metric 1409 */ 1410 pref = 1; 1411 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1412 1413 /* Do not install host routes directly to hosts, to avoid 1414 * interfering with ARP entries in the kernel table. 1415 */ 1416 if (RT_ISHOST(RT) 1417 && ntohl(RT->rt_dst) == RT->rt_gate) 1418 return 0; 1419 1420 } else { 1421 /* This is an interface route. 1422 * Do not install routes for "external" remote interfaces. 1423 */ 1424 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL)) 1425 return 0; 1426 1427 /* Interfaces should override received routes. 1428 */ 1429 pref = 0; 1430 ags |= (AGS_IF | AGS_CORS_GATE); 1431 1432 /* If it is not an interface, or an alias for an interface, 1433 * it must be a "gateway." 1434 * 1435 * If it is a "remote" interface, it is also a "gateway" to 1436 * the kernel if is not a alias. 1437 */ 1438 if (RT->rt_ifp == 0 1439 || (RT->rt_ifp->int_state & IS_REMOTE)) 1440 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1441 } 1442 1443 /* If RIP is off and IRDP is on, let the route to the discovered 1444 * route suppress any RIP routes. Eventually the RIP routes 1445 * will time-out and be deleted. This reaches the steady-state 1446 * quicker. 1447 */ 1448 if ((RT->rt_state & RS_RDISC) && rip_sock < 0) 1449 ags |= AGS_CORS_GATE; 1450 1451 metric = RT->rt_metric; 1452 if (metric == HOPCNT_INFINITY) { 1453 /* if the route is dead, so try hard to aggregate. */ 1454 pref = HOPCNT_INFINITY; 1455 ags |= (AGS_FINE_GATE | AGS_SUPPRESS); 1456 ags &= ~(AGS_IF | AGS_CORS_GATE); 1457 } 1458 1459 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0, 1460 metric,pref, 0, 0, ags, kern_out); 1461 return 0; 1462 #undef RT 1463 } 1464 1465 1466 /* Update the kernel table to match the daemon table. 1467 */ 1468 static void 1469 fix_kern(void) 1470 { 1471 int i; 1472 struct khash *k, **pk; 1473 1474 1475 need_kern = age_timer; 1476 1477 /* Walk daemon table, updating the copy of the kernel table. 1478 */ 1479 (void)rn_walktree(rhead, walk_kern, 0); 1480 ag_flush(0,0,kern_out); 1481 1482 for (i = 0; i < KHASH_SIZE; i++) { 1483 for (pk = &khash_bins[i]; (k = *pk) != 0; ) { 1484 /* Do not touch static routes */ 1485 if (k->k_state & KS_STATIC) { 1486 kern_check_static(k,0); 1487 pk = &k->k_next; 1488 continue; 1489 } 1490 1491 /* check hold on routes deleted by the operator */ 1492 if (k->k_keep > now.tv_sec) { 1493 /* ensure we check when the hold is over */ 1494 LIM_SEC(need_kern, k->k_keep); 1495 /* mark for the next cycle */ 1496 k->k_state |= KS_DELETE; 1497 pk = &k->k_next; 1498 continue; 1499 } 1500 1501 if ((k->k_state & KS_DELETE) 1502 && !(k->k_state & KS_DYNAMIC)) { 1503 kern_ioctl(k, RTM_DELETE, 0); 1504 *pk = k->k_next; 1505 free(k); 1506 continue; 1507 } 1508 1509 if (k->k_state & KS_DEL_ADD) 1510 kern_ioctl(k, RTM_DELETE, 0); 1511 1512 if (k->k_state & KS_ADD) { 1513 kern_ioctl(k, RTM_ADD, 1514 ((0 != (k->k_state & (KS_GATEWAY 1515 | KS_DYNAMIC))) 1516 ? RTF_GATEWAY : 0)); 1517 } else if (k->k_state & KS_CHANGE) { 1518 kern_ioctl(k, RTM_CHANGE, 1519 ((0 != (k->k_state & (KS_GATEWAY 1520 | KS_DYNAMIC))) 1521 ? RTF_GATEWAY : 0)); 1522 } 1523 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD); 1524 1525 /* Mark this route to be deleted in the next cycle. 1526 * This deletes routes that disappear from the 1527 * daemon table, since the normal aging code 1528 * will clear the bit for routes that have not 1529 * disappeared from the daemon table. 1530 */ 1531 k->k_state |= KS_DELETE; 1532 pk = &k->k_next; 1533 } 1534 } 1535 } 1536 1537 1538 /* Delete a static route in the image of the kernel table. 1539 */ 1540 void 1541 del_static(naddr dst, 1542 naddr mask, 1543 naddr gate, 1544 int gone) 1545 { 1546 struct khash *k; 1547 struct rt_entry *rt; 1548 1549 /* Just mark it in the table to be deleted next time the kernel 1550 * table is updated. 1551 * If it has already been deleted, mark it as such, and set its 1552 * keep-timer so that it will not be deleted again for a while. 1553 * This lets the operator delete a route added by the daemon 1554 * and add a replacement. 1555 */ 1556 k = kern_find(dst, mask, 0); 1557 if (k != 0 && (gate == 0 || k->k_gate == gate)) { 1558 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK); 1559 k->k_state |= KS_DELETE; 1560 if (gone) { 1561 k->k_state |= KS_DELETED; 1562 k->k_keep = now.tv_sec + K_KEEP_LIM; 1563 } 1564 } 1565 1566 rt = rtget(dst, mask); 1567 if (rt != 0 && (rt->rt_state & RS_STATIC)) 1568 rtbad(rt); 1569 } 1570 1571 1572 /* Delete all routes generated from ICMP Redirects that use a given gateway, 1573 * as well as old redirected routes. 1574 */ 1575 void 1576 del_redirects(naddr bad_gate, 1577 time_t old) 1578 { 1579 int i; 1580 struct khash *k; 1581 1582 1583 for (i = 0; i < KHASH_SIZE; i++) { 1584 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1585 if (!(k->k_state & KS_DYNAMIC) 1586 || (k->k_state & KS_STATIC)) 1587 continue; 1588 1589 if (k->k_gate != bad_gate 1590 && k->k_redirect_time > old 1591 && !supplier) 1592 continue; 1593 1594 k->k_state |= KS_DELETE; 1595 k->k_state &= ~KS_DYNAMIC; 1596 need_kern.tv_sec = now.tv_sec; 1597 trace_act("mark redirected %s --> %s for deletion", 1598 addrname(k->k_dst, k->k_mask, 0), 1599 naddr_ntoa(k->k_gate)); 1600 } 1601 } 1602 } 1603 1604 1605 /* Start the daemon tables. 1606 */ 1607 extern int max_keylen; 1608 1609 void 1610 rtinit(void) 1611 { 1612 int i; 1613 struct ag_info *ag; 1614 1615 /* Initialize the radix trees */ 1616 max_keylen = sizeof(struct sockaddr_in); 1617 rn_init(); 1618 rn_inithead((void**)&rhead, 32); 1619 1620 /* mark all of the slots in the table free */ 1621 ag_avail = ag_slots; 1622 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) { 1623 ag->ag_fine = ag+1; 1624 ag++; 1625 } 1626 } 1627 1628 1629 #ifdef _HAVE_SIN_LEN 1630 static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET}; 1631 static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET}; 1632 #else 1633 static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET}; 1634 static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET}; 1635 #endif 1636 1637 1638 static void 1639 set_need_flash(void) 1640 { 1641 if (!need_flash) { 1642 need_flash = 1; 1643 /* Do not send the flash update immediately. Wait a little 1644 * while to hear from other routers. 1645 */ 1646 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME; 1647 } 1648 } 1649 1650 1651 /* Get a particular routing table entry 1652 */ 1653 struct rt_entry * 1654 rtget(naddr dst, naddr mask) 1655 { 1656 struct rt_entry *rt; 1657 1658 dst_sock.sin_addr.s_addr = dst; 1659 mask_sock.sin_addr.s_addr = mask; 1660 masktrim(&mask_sock); 1661 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead); 1662 if (!rt 1663 || rt->rt_dst != dst 1664 || rt->rt_mask != mask) 1665 return 0; 1666 1667 return rt; 1668 } 1669 1670 1671 /* Find a route to dst as the kernel would. 1672 */ 1673 struct rt_entry * 1674 rtfind(naddr dst) 1675 { 1676 dst_sock.sin_addr.s_addr = dst; 1677 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead); 1678 } 1679 1680 1681 /* add a route to the table 1682 */ 1683 void 1684 rtadd(naddr dst, 1685 naddr mask, 1686 u_int state, /* rt_state for the entry */ 1687 struct rt_spare *new) 1688 { 1689 struct rt_entry *rt; 1690 naddr smask; 1691 int i; 1692 struct rt_spare *rts; 1693 1694 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd"); 1695 memset(rt, 0, sizeof(*rt)); 1696 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) 1697 rts->rts_metric = HOPCNT_INFINITY; 1698 1699 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock; 1700 rt->rt_dst = dst; 1701 rt->rt_dst_sock.sin_family = AF_INET; 1702 #ifdef _HAVE_SIN_LEN 1703 rt->rt_dst_sock.sin_len = dst_sock.sin_len; 1704 #endif 1705 if (mask != HOST_MASK) { 1706 smask = std_mask(dst); 1707 if ((smask & ~mask) == 0 && mask > smask) 1708 state |= RS_SUBNET; 1709 } 1710 mask_sock.sin_addr.s_addr = mask; 1711 masktrim(&mask_sock); 1712 rt->rt_mask = mask; 1713 rt->rt_state = state; 1714 rt->rt_spares[0] = *new; 1715 rt->rt_time = now.tv_sec; 1716 rt->rt_poison_metric = HOPCNT_INFINITY; 1717 rt->rt_seqno = update_seqno; 1718 1719 if (++total_routes == MAX_ROUTES) 1720 msglog("have maximum (%d) routes", total_routes); 1721 if (TRACEACTIONS) 1722 trace_add_del("Add", rt); 1723 1724 need_kern.tv_sec = now.tv_sec; 1725 set_need_flash(); 1726 1727 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock, 1728 rhead, rt->rt_nodes)) { 1729 msglog("rnh_addaddr() failed for %s mask=%#lx", 1730 naddr_ntoa(dst), (u_long)mask); 1731 } 1732 } 1733 1734 1735 /* notice a changed route 1736 */ 1737 void 1738 rtchange(struct rt_entry *rt, 1739 u_int state, /* new state bits */ 1740 struct rt_spare *new, 1741 char *label) 1742 { 1743 if (rt->rt_metric != new->rts_metric) { 1744 /* Fix the kernel immediately if it seems the route 1745 * has gone bad, since there may be a working route that 1746 * aggregates this route. 1747 */ 1748 if (new->rts_metric == HOPCNT_INFINITY) { 1749 need_kern.tv_sec = now.tv_sec; 1750 if (new->rts_time >= now.tv_sec - EXPIRE_TIME) 1751 new->rts_time = now.tv_sec - EXPIRE_TIME; 1752 } 1753 rt->rt_seqno = update_seqno; 1754 set_need_flash(); 1755 } 1756 1757 if (rt->rt_gate != new->rts_gate) { 1758 need_kern.tv_sec = now.tv_sec; 1759 rt->rt_seqno = update_seqno; 1760 set_need_flash(); 1761 } 1762 1763 state |= (rt->rt_state & RS_SUBNET); 1764 1765 /* Keep various things from deciding ageless routes are stale. 1766 */ 1767 if (!AGE_RT(state, new->rts_ifp)) 1768 new->rts_time = now.tv_sec; 1769 1770 if (TRACEACTIONS) 1771 trace_change(rt, state, new, 1772 label ? label : "Chg "); 1773 1774 rt->rt_state = state; 1775 rt->rt_spares[0] = *new; 1776 } 1777 1778 1779 /* check for a better route among the spares 1780 */ 1781 static struct rt_spare * 1782 rts_better(struct rt_entry *rt) 1783 { 1784 struct rt_spare *rts, *rts1; 1785 int i; 1786 1787 /* find the best alternative among the spares */ 1788 rts = rt->rt_spares+1; 1789 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) { 1790 if (BETTER_LINK(rt,rts1,rts)) 1791 rts = rts1; 1792 } 1793 1794 return rts; 1795 } 1796 1797 1798 /* switch to a backup route 1799 */ 1800 void 1801 rtswitch(struct rt_entry *rt, 1802 struct rt_spare *rts) 1803 { 1804 struct rt_spare swap; 1805 char label[10]; 1806 1807 1808 /* Do not change permanent routes */ 1809 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC 1810 | RS_NET_SYN | RS_IF))) 1811 return; 1812 1813 /* find the best alternative among the spares */ 1814 if (rts == 0) 1815 rts = rts_better(rt); 1816 1817 /* Do not bother if it is not worthwhile. 1818 */ 1819 if (!BETTER_LINK(rt, rts, rt->rt_spares)) 1820 return; 1821 1822 swap = rt->rt_spares[0]; 1823 (void)sprintf(label, "Use #%d", (int)(rts - rt->rt_spares)); 1824 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label); 1825 if (swap.rts_metric == HOPCNT_INFINITY) { 1826 *rts = rts_empty; 1827 } else { 1828 *rts = swap; 1829 } 1830 } 1831 1832 1833 void 1834 rtdelete(struct rt_entry *rt) 1835 { 1836 struct khash *k; 1837 1838 1839 if (TRACEACTIONS) 1840 trace_add_del("Del", rt); 1841 1842 k = kern_find(rt->rt_dst, rt->rt_mask, 0); 1843 if (k != 0) { 1844 k->k_state |= KS_DELETE; 1845 need_kern.tv_sec = now.tv_sec; 1846 } 1847 1848 dst_sock.sin_addr.s_addr = rt->rt_dst; 1849 mask_sock.sin_addr.s_addr = rt->rt_mask; 1850 masktrim(&mask_sock); 1851 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock, 1852 rhead)) { 1853 msglog("rnh_deladdr() failed"); 1854 } else { 1855 free(rt); 1856 total_routes--; 1857 } 1858 } 1859 1860 1861 void 1862 rts_delete(struct rt_entry *rt, 1863 struct rt_spare *rts) 1864 { 1865 trace_upslot(rt, rts, &rts_empty); 1866 *rts = rts_empty; 1867 } 1868 1869 1870 /* Get rid of a bad route, and try to switch to a replacement. 1871 */ 1872 void 1873 rtbad(struct rt_entry *rt) 1874 { 1875 struct rt_spare new; 1876 1877 /* Poison the route */ 1878 new = rt->rt_spares[0]; 1879 new.rts_metric = HOPCNT_INFINITY; 1880 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0); 1881 rtswitch(rt, 0); 1882 } 1883 1884 1885 /* Junk a RS_NET_SYN or RS_LOCAL route, 1886 * unless it is needed by another interface. 1887 */ 1888 void 1889 rtbad_sub(struct rt_entry *rt) 1890 { 1891 struct interface *ifp, *ifp1; 1892 struct intnet *intnetp; 1893 u_int state; 1894 1895 1896 ifp1 = 0; 1897 state = 0; 1898 1899 if (rt->rt_state & RS_LOCAL) { 1900 /* Is this the route through loopback for the interface? 1901 * If so, see if it is used by any other interfaces, such 1902 * as a point-to-point interface with the same local address. 1903 */ 1904 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1905 /* Retain it if another interface needs it. 1906 */ 1907 if (ifp->int_addr == rt->rt_ifp->int_addr) { 1908 state |= RS_LOCAL; 1909 ifp1 = ifp; 1910 break; 1911 } 1912 } 1913 1914 } 1915 1916 if (!(state & RS_LOCAL)) { 1917 /* Retain RIPv1 logical network route if there is another 1918 * interface that justifies it. 1919 */ 1920 if (rt->rt_state & RS_NET_SYN) { 1921 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1922 if ((ifp->int_state & IS_NEED_NET_SYN) 1923 && rt->rt_mask == ifp->int_std_mask 1924 && rt->rt_dst == ifp->int_std_addr) { 1925 state |= RS_NET_SYN; 1926 ifp1 = ifp; 1927 break; 1928 } 1929 } 1930 } 1931 1932 /* or if there is an authority route that needs it. */ 1933 for (intnetp = intnets; 1934 intnetp != 0; 1935 intnetp = intnetp->intnet_next) { 1936 if (intnetp->intnet_addr == rt->rt_dst 1937 && intnetp->intnet_mask == rt->rt_mask) { 1938 state |= (RS_NET_SYN | RS_NET_INT); 1939 break; 1940 } 1941 } 1942 } 1943 1944 if (ifp1 != 0 || (state & RS_NET_SYN)) { 1945 struct rt_spare new = rt->rt_spares[0]; 1946 new.rts_ifp = ifp1; 1947 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state), 1948 &new, 0); 1949 } else { 1950 rtbad(rt); 1951 } 1952 } 1953 1954 1955 /* Called while walking the table looking for sick interfaces 1956 * or after a time change. 1957 */ 1958 /* ARGSUSED */ 1959 int 1960 walk_bad(struct radix_node *rn, 1961 struct walkarg *argp UNUSED) 1962 { 1963 #define RT ((struct rt_entry *)rn) 1964 struct rt_spare *rts; 1965 int i; 1966 1967 1968 /* fix any spare routes through the interface 1969 */ 1970 rts = RT->rt_spares; 1971 for (i = NUM_SPARES; i != 1; i--) { 1972 rts++; 1973 if (rts->rts_metric < HOPCNT_INFINITY 1974 && (rts->rts_ifp == 0 1975 || (rts->rts_ifp->int_state & IS_BROKE))) 1976 rts_delete(RT, rts); 1977 } 1978 1979 /* Deal with the main route 1980 */ 1981 /* finished if it has been handled before or if its interface is ok 1982 */ 1983 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE)) 1984 return 0; 1985 1986 /* Bad routes for other than interfaces are easy. 1987 */ 1988 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) { 1989 rtbad(RT); 1990 return 0; 1991 } 1992 1993 rtbad_sub(RT); 1994 return 0; 1995 #undef RT 1996 } 1997 1998 1999 /* Check the age of an individual route. 2000 */ 2001 /* ARGSUSED */ 2002 static int 2003 walk_age(struct radix_node *rn, 2004 struct walkarg *argp UNUSED) 2005 { 2006 #define RT ((struct rt_entry *)rn) 2007 struct interface *ifp; 2008 struct rt_spare *rts; 2009 int i; 2010 2011 2012 /* age all of the spare routes, including the primary route 2013 * currently in use 2014 */ 2015 rts = RT->rt_spares; 2016 for (i = NUM_SPARES; i != 0; i--, rts++) { 2017 2018 ifp = rts->rts_ifp; 2019 if (i == NUM_SPARES) { 2020 if (!AGE_RT(RT->rt_state, ifp)) { 2021 /* Keep various things from deciding ageless 2022 * routes are stale 2023 */ 2024 rts->rts_time = now.tv_sec; 2025 continue; 2026 } 2027 2028 /* forget RIP routes after RIP has been turned off. 2029 */ 2030 if (rip_sock < 0) { 2031 rtdelete(RT); 2032 return 0; 2033 } 2034 } 2035 2036 /* age failing routes 2037 */ 2038 if (age_bad_gate == rts->rts_gate 2039 && rts->rts_time >= now_stale) { 2040 rts->rts_time -= SUPPLY_INTERVAL; 2041 } 2042 2043 /* trash the spare routes when they go bad */ 2044 if (rts->rts_metric < HOPCNT_INFINITY 2045 && now_garbage > rts->rts_time 2046 && i != NUM_SPARES) 2047 rts_delete(RT, rts); 2048 } 2049 2050 2051 /* finished if the active route is still fresh */ 2052 if (now_stale <= RT->rt_time) 2053 return 0; 2054 2055 /* try to switch to an alternative */ 2056 rtswitch(RT, 0); 2057 2058 /* Delete a dead route after it has been publically mourned. */ 2059 if (now_garbage > RT->rt_time) { 2060 rtdelete(RT); 2061 return 0; 2062 } 2063 2064 /* Start poisoning a bad route before deleting it. */ 2065 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) { 2066 struct rt_spare new = RT->rt_spares[0]; 2067 new.rts_metric = HOPCNT_INFINITY; 2068 rtchange(RT, RT->rt_state, &new, 0); 2069 } 2070 return 0; 2071 } 2072 2073 2074 /* Watch for dead routes and interfaces. 2075 */ 2076 void 2077 age(naddr bad_gate) 2078 { 2079 struct interface *ifp; 2080 int need_query = 0; 2081 2082 /* If not listening to RIP, there is no need to age the routes in 2083 * the table. 2084 */ 2085 age_timer.tv_sec = (now.tv_sec 2086 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL)); 2087 2088 /* Check for dead IS_REMOTE interfaces by timing their 2089 * transmissions. 2090 */ 2091 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 2092 if (!(ifp->int_state & IS_REMOTE)) 2093 continue; 2094 2095 /* ignore unreachable remote interfaces */ 2096 if (!check_remote(ifp)) 2097 continue; 2098 2099 /* Restore remote interface that has become reachable 2100 */ 2101 if (ifp->int_state & IS_BROKE) 2102 if_ok(ifp, "remote "); 2103 2104 if (ifp->int_act_time != NEVER 2105 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) { 2106 msglog("remote interface %s to %s timed out after" 2107 " %ld:%ld", 2108 ifp->int_name, 2109 naddr_ntoa(ifp->int_dstaddr), 2110 (now.tv_sec - ifp->int_act_time)/60, 2111 (now.tv_sec - ifp->int_act_time)%60); 2112 if_sick(ifp); 2113 } 2114 2115 /* If we have not heard from the other router 2116 * recently, ask it. 2117 */ 2118 if (now.tv_sec >= ifp->int_query_time) { 2119 ifp->int_query_time = NEVER; 2120 need_query = 1; 2121 } 2122 } 2123 2124 /* Age routes. */ 2125 age_bad_gate = bad_gate; 2126 (void)rn_walktree(rhead, walk_age, 0); 2127 2128 /* delete old redirected routes to keep the kernel table small 2129 * and prevent blackholes 2130 */ 2131 del_redirects(bad_gate, now.tv_sec-STALE_TIME); 2132 2133 /* Update the kernel routing table. */ 2134 fix_kern(); 2135 2136 /* poke reticent remote gateways */ 2137 if (need_query) 2138 rip_query(); 2139 } 2140