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: src/sbin/routed/table.c,v 1.9.2.2 2000/08/14 17:00:04 sheldonh Exp $ 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 44 static struct rt_spare *rts_better(struct rt_entry *); 45 static struct rt_spare rts_empty = {0,0,0,HOPCNT_INFINITY,0,0,0}; 46 static void set_need_flash(void); 47 #ifdef _HAVE_SIN_LEN 48 static void masktrim(struct sockaddr_in *ap); 49 #else 50 static void masktrim(struct sockaddr_in_new *ap); 51 #endif 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 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 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 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 == 0) 178 ag_corsest = ag->ag_fine; 179 else 180 ag->ag_cors->ag_fine = ag->ag_fine; 181 182 if (ag->ag_fine == 0) 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_cors->ag_seqno > ag->ag_seqno) 256 ag_cors->ag_seqno = ag->ag_seqno; 257 if (AG_IS_REDUN(ag->ag_state) 258 && ag_cors->ag_mask==ag->ag_mask<<1) { 259 if (ag_cors->ag_dst_h == dst_h) 260 ag_cors->ag_state |= AGS_REDUN0; 261 else 262 ag_cors->ag_state |= AGS_REDUN1; 263 } 264 if (ag->ag_tag != ag_cors->ag_tag) 265 ag_cors->ag_tag = 0; 266 if (ag->ag_nhop != ag_cors->ag_nhop) 267 ag_cors->ag_nhop = 0; 268 break; 269 } 270 } 271 } 272 273 /* That route has either been output or suppressed */ 274 ag_cors = ag->ag_cors; 275 ag_del(ag); 276 } 277 278 CHECK_AG(); 279 } 280 281 282 /* Try to aggregate a route with previous routes. 283 */ 284 void 285 ag_check(naddr dst, 286 naddr mask, 287 naddr gate, 288 naddr nhop, 289 char metric, 290 char pref, 291 u_int seqnum, 292 u_short tag, 293 u_short state, 294 void (*out)(struct ag_info *)) /* output using this */ 295 { 296 struct ag_info *ag, *nag, *ag_cors; 297 naddr xaddr; 298 int x; 299 300 dst = ntohl(dst); 301 302 /* Punt non-contiguous subnet masks. 303 * 304 * (X & -X) contains a single bit if and only if X is a power of 2. 305 * (X + (X & -X)) == 0 if and only if X is a power of 2. 306 */ 307 if ((mask & -mask) + mask != 0) { 308 struct ag_info nc_ag; 309 310 nc_ag.ag_dst_h = dst; 311 nc_ag.ag_mask = mask; 312 nc_ag.ag_gate = gate; 313 nc_ag.ag_nhop = nhop; 314 nc_ag.ag_metric = metric; 315 nc_ag.ag_pref = pref; 316 nc_ag.ag_tag = tag; 317 nc_ag.ag_state = state; 318 nc_ag.ag_seqno = seqnum; 319 out(&nc_ag); 320 return; 321 } 322 323 /* Search for the right slot in the aggregation table. 324 */ 325 ag_cors = NULL; 326 ag = ag_corsest; 327 while (ag != NULL) { 328 if (ag->ag_mask >= mask) 329 break; 330 331 /* Suppress old routes (i.e. combine with compatible routes 332 * with coarser masks) as we look for the right slot in the 333 * aggregation table for the new route. 334 * A route to an address less than the current destination 335 * will not be affected by the current route or any route 336 * seen hereafter. That means it is safe to suppress it. 337 * This check keeps poor routes (e.g. with large hop counts) 338 * from preventing suppression of finer routes. 339 */ 340 if (ag_cors != NULL 341 && ag->ag_dst_h < dst 342 && (ag->ag_state & AGS_SUPPRESS) 343 && ag_cors->ag_pref <= ag->ag_pref 344 && (ag->ag_dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h 345 && (ag_cors->ag_gate == ag->ag_gate 346 || (ag->ag_state & AGS_FINE_GATE) 347 || (ag_cors->ag_state & AGS_CORS_GATE))) { 348 if (ag_cors->ag_seqno > ag->ag_seqno) 349 ag_cors->ag_seqno = ag->ag_seqno; 350 /* If the suppressed target was redundant, 351 * then mark the suppressor redundant. 352 */ 353 if (AG_IS_REDUN(ag->ag_state) 354 && ag_cors->ag_mask == ag->ag_mask<<1) { 355 if (ag_cors->ag_dst_h == dst) 356 ag_cors->ag_state |= AGS_REDUN0; 357 else 358 ag_cors->ag_state |= AGS_REDUN1; 359 } 360 if (ag->ag_tag != ag_cors->ag_tag) 361 ag_cors->ag_tag = 0; 362 if (ag->ag_nhop != ag_cors->ag_nhop) 363 ag_cors->ag_nhop = 0; 364 ag_del(ag); 365 CHECK_AG(); 366 } else { 367 ag_cors = ag; 368 } 369 ag = ag_cors->ag_fine; 370 } 371 372 /* If we find the even/odd twin of the new route, and if the 373 * masks and so forth are equal, we can aggregate them. 374 * We can probably promote one of the pair. 375 * 376 * Since the routes are encountered in lexical order, 377 * the new route must be odd. However, the second or later 378 * times around this loop, it could be the even twin promoted 379 * from the even/odd pair of twins of the finer route. 380 */ 381 while (ag != NULL 382 && ag->ag_mask == mask 383 && ((ag->ag_dst_h ^ dst) & (mask<<1)) == 0) { 384 385 /* Here we know the target route and the route in the current 386 * slot have the same netmasks and differ by at most the 387 * last bit. They are either for the same destination, or 388 * for an even/odd pair of destinations. 389 */ 390 if (ag->ag_dst_h == dst) { 391 /* We have two routes to the same destination. 392 * Routes are encountered in lexical order, so a 393 * route is never promoted until the parent route is 394 * already present. So we know that the new route is 395 * a promoted (or aggregated) pair and the route 396 * already in the slot is the explicit route. 397 * 398 * Prefer the best route if their metrics differ, 399 * or the aggregated one if not, following a sort 400 * of longest-match rule. 401 */ 402 if (pref <= ag->ag_pref) { 403 ag->ag_gate = gate; 404 ag->ag_nhop = nhop; 405 ag->ag_tag = tag; 406 ag->ag_metric = metric; 407 ag->ag_pref = pref; 408 x = ag->ag_state; 409 ag->ag_state = state; 410 state = x; 411 } 412 413 /* The sequence number controls flash updating, 414 * and should be the smaller of the two. 415 */ 416 if (ag->ag_seqno > seqnum) 417 ag->ag_seqno = seqnum; 418 419 /* Some bits are set if they are set on either route, 420 * except when the route is for an interface. 421 */ 422 if (!(ag->ag_state & AGS_IF)) 423 ag->ag_state |= (state & (AGS_AGGREGATE_EITHER 424 | AGS_REDUN0 425 | AGS_REDUN1)); 426 return; 427 } 428 429 /* If one of the routes can be promoted and the other can 430 * be suppressed, it may be possible to combine them or 431 * worthwhile to promote one. 432 * 433 * Any route that can be promoted is always 434 * marked to be eligible to be suppressed. 435 */ 436 if (!((state & AGS_AGGREGATE) 437 && (ag->ag_state & AGS_SUPPRESS)) 438 && !((ag->ag_state & AGS_AGGREGATE) 439 && (state & AGS_SUPPRESS))) 440 break; 441 442 /* A pair of even/odd twin routes can be combined 443 * if either is redundant, or if they are via the 444 * same gateway and have the same metric. 445 */ 446 if (AG_IS_REDUN(ag->ag_state) 447 || AG_IS_REDUN(state) 448 || (ag->ag_gate == gate 449 && ag->ag_pref == pref 450 && (state & ag->ag_state & AGS_AGGREGATE) != 0)) { 451 452 /* We have both the even and odd pairs. 453 * Since the routes are encountered in order, 454 * the route in the slot must be the even twin. 455 * 456 * Combine and promote (aggregate) the pair of routes. 457 */ 458 if (seqnum > ag->ag_seqno) 459 seqnum = ag->ag_seqno; 460 if (!AG_IS_REDUN(state)) 461 state &= ~AGS_REDUN1; 462 if (AG_IS_REDUN(ag->ag_state)) 463 state |= AGS_REDUN0; 464 else 465 state &= ~AGS_REDUN0; 466 state |= (ag->ag_state & AGS_AGGREGATE_EITHER); 467 if (ag->ag_tag != tag) 468 tag = 0; 469 if (ag->ag_nhop != nhop) 470 nhop = 0; 471 472 /* Get rid of the even twin that was already 473 * in the slot. 474 */ 475 ag_del(ag); 476 477 } else if (ag->ag_pref >= pref 478 && (ag->ag_state & AGS_AGGREGATE)) { 479 /* If we cannot combine the pair, maybe the route 480 * with the worse metric can be promoted. 481 * 482 * Promote the old, even twin, by giving its slot 483 * in the table to the new, odd twin. 484 */ 485 ag->ag_dst_h = dst; 486 487 xaddr = ag->ag_gate; 488 ag->ag_gate = gate; 489 gate = xaddr; 490 491 xaddr = ag->ag_nhop; 492 ag->ag_nhop = nhop; 493 nhop = xaddr; 494 495 x = ag->ag_tag; 496 ag->ag_tag = tag; 497 tag = x; 498 499 /* The promoted route is even-redundant only if the 500 * even twin was fully redundant. It is not 501 * odd-redundant because the odd-twin will still be 502 * in the table. 503 */ 504 x = ag->ag_state; 505 if (!AG_IS_REDUN(x)) 506 x &= ~AGS_REDUN0; 507 x &= ~AGS_REDUN1; 508 ag->ag_state = state; 509 state = x; 510 511 x = ag->ag_metric; 512 ag->ag_metric = metric; 513 metric = x; 514 515 x = ag->ag_pref; 516 ag->ag_pref = pref; 517 pref = x; 518 519 /* take the newest sequence number */ 520 if (seqnum >= ag->ag_seqno) 521 seqnum = ag->ag_seqno; 522 else 523 ag->ag_seqno = seqnum; 524 525 } else { 526 if (!(state & AGS_AGGREGATE)) 527 break; /* cannot promote either twin */ 528 529 /* Promote the new, odd twin by shaving its 530 * mask and address. 531 * The promoted route is odd-redundant only if the 532 * odd twin was fully redundant. It is not 533 * even-redundant because the even twin is still in 534 * the table. 535 */ 536 if (!AG_IS_REDUN(state)) 537 state &= ~AGS_REDUN1; 538 state &= ~AGS_REDUN0; 539 if (seqnum > ag->ag_seqno) 540 seqnum = ag->ag_seqno; 541 else 542 ag->ag_seqno = seqnum; 543 } 544 545 mask <<= 1; 546 dst &= mask; 547 548 if (ag_cors == NULL) { 549 ag = ag_corsest; 550 break; 551 } 552 ag = ag_cors; 553 ag_cors = ag->ag_cors; 554 } 555 556 /* When we can no longer promote and combine routes, 557 * flush the old route in the target slot. Also flush 558 * any finer routes that we know will never be aggregated by 559 * the new route. 560 * 561 * In case we moved toward coarser masks, 562 * get back where we belong 563 */ 564 if (ag != NULL 565 && ag->ag_mask < mask) { 566 ag_cors = ag; 567 ag = ag->ag_fine; 568 } 569 570 /* Empty the target slot 571 */ 572 if (ag != NULL && ag->ag_mask == mask) { 573 ag_flush(ag->ag_dst_h, ag->ag_mask, out); 574 ag = (ag_cors == NULL) ? ag_corsest : ag_cors->ag_fine; 575 } 576 577 #ifdef DEBUG_AG 578 fflush(stderr); 579 if (ag == NULL && ag_cors != ag_finest) 580 abort(); 581 if (ag_cors == NULL && ag != ag_corsest) 582 abort(); 583 if (ag != NULL && ag->ag_cors != ag_cors) 584 abort(); 585 if (ag_cors != NULL && ag_cors->ag_fine != ag) 586 abort(); 587 CHECK_AG(); 588 #endif 589 590 /* Save the new route on the end of the table. 591 */ 592 nag = ag_avail; 593 ag_avail = nag->ag_fine; 594 595 nag->ag_dst_h = dst; 596 nag->ag_mask = mask; 597 nag->ag_gate = gate; 598 nag->ag_nhop = nhop; 599 nag->ag_metric = metric; 600 nag->ag_pref = pref; 601 nag->ag_tag = tag; 602 nag->ag_state = state; 603 nag->ag_seqno = seqnum; 604 605 nag->ag_fine = ag; 606 if (ag != NULL) 607 ag->ag_cors = nag; 608 else 609 ag_finest = nag; 610 nag->ag_cors = ag_cors; 611 if (ag_cors == NULL) 612 ag_corsest = nag; 613 else 614 ag_cors->ag_fine = nag; 615 CHECK_AG(); 616 } 617 618 619 #define NAME0_LEN 14 620 static const char * 621 rtm_type_name(u_char type) 622 { 623 static const char *rtm_types[] = { 624 "RTM_ADD", 625 "RTM_DELETE", 626 "RTM_CHANGE", 627 "RTM_GET", 628 "RTM_LOSING", 629 "RTM_REDIRECT", 630 "RTM_MISS", 631 "RTM_LOCK", 632 "RTM_OLDADD", 633 "RTM_OLDDEL", 634 "RTM_RESOLVE", 635 "RTM_NEWADDR", 636 "RTM_DELADDR", 637 "RTM_IFINFO", 638 "RTM_NEWMADDR", 639 "RTM_DELMADDR" 640 }; 641 #define NEW_RTM_PAT "RTM type %#x" 642 static char name0[sizeof(NEW_RTM_PAT)+2]; 643 644 645 if (type > sizeof(rtm_types)/sizeof(rtm_types[0]) 646 || type == 0) { 647 snprintf(name0, sizeof(name0), NEW_RTM_PAT, type); 648 return name0; 649 } else { 650 return rtm_types[type-1]; 651 } 652 #undef NEW_RTM_PAT 653 } 654 655 656 /* Trim a mask in a sockaddr 657 * Produce a length of 0 for an address of 0. 658 * Otherwise produce the index of the first zero byte. 659 */ 660 void 661 #ifdef _HAVE_SIN_LEN 662 masktrim(struct sockaddr_in *ap) 663 #else 664 masktrim(struct sockaddr_in_new *ap) 665 #endif 666 { 667 char *cp; 668 669 if (ap->sin_addr.s_addr == 0) { 670 ap->sin_len = 0; 671 return; 672 } 673 cp = (char *)(&ap->sin_addr.s_addr+1); 674 while (*--cp == 0) 675 continue; 676 ap->sin_len = cp - (char*)ap + 1; 677 } 678 679 680 /* Tell the kernel to add, delete or change a route 681 */ 682 static void 683 rtioctl(int action, /* RTM_DELETE, etc */ 684 naddr dst, 685 naddr gate, 686 naddr mask, 687 int metric, 688 int flags) 689 { 690 struct { 691 struct rt_msghdr w_rtm; 692 struct sockaddr_in w_dst; 693 struct sockaddr_in w_gate; 694 #ifdef _HAVE_SA_LEN 695 struct sockaddr_in w_mask; 696 #else 697 struct sockaddr_in_new w_mask; 698 #endif 699 } w; 700 long cc; 701 # define PAT " %-10s %s metric=%d flags=%#x" 702 # define ARGS rtm_type_name(action), rtname(dst,mask,gate), metric, flags 703 704 again: 705 memset(&w, 0, sizeof(w)); 706 w.w_rtm.rtm_msglen = sizeof(w); 707 w.w_rtm.rtm_version = RTM_VERSION; 708 w.w_rtm.rtm_type = action; 709 w.w_rtm.rtm_flags = flags; 710 w.w_rtm.rtm_seq = ++rt_sock_seqno; 711 w.w_rtm.rtm_addrs = RTA_DST|RTA_GATEWAY; 712 if (metric != 0 || action == RTM_CHANGE) { 713 w.w_rtm.rtm_rmx.rmx_hopcount = metric; 714 w.w_rtm.rtm_inits |= RTV_HOPCOUNT; 715 } 716 w.w_dst.sin_family = AF_INET; 717 w.w_dst.sin_addr.s_addr = dst; 718 w.w_gate.sin_family = AF_INET; 719 w.w_gate.sin_addr.s_addr = gate; 720 #ifdef _HAVE_SA_LEN 721 w.w_dst.sin_len = sizeof(w.w_dst); 722 w.w_gate.sin_len = sizeof(w.w_gate); 723 #endif 724 if (mask == HOST_MASK) { 725 w.w_rtm.rtm_flags |= RTF_HOST; 726 w.w_rtm.rtm_msglen -= sizeof(w.w_mask); 727 } else { 728 w.w_rtm.rtm_addrs |= RTA_NETMASK; 729 w.w_mask.sin_addr.s_addr = htonl(mask); 730 #ifdef _HAVE_SA_LEN 731 masktrim(&w.w_mask); 732 if (w.w_mask.sin_len == 0) 733 w.w_mask.sin_len = sizeof(long); 734 w.w_rtm.rtm_msglen -= (sizeof(w.w_mask) - w.w_mask.sin_len); 735 #endif 736 } 737 738 #ifndef NO_INSTALL 739 cc = write(rt_sock, &w, w.w_rtm.rtm_msglen); 740 if (cc < 0) { 741 if (errno == ESRCH 742 && (action == RTM_CHANGE || action == RTM_DELETE)) { 743 trace_act("route disappeared before" PAT, ARGS); 744 if (action == RTM_CHANGE) { 745 action = RTM_ADD; 746 goto again; 747 } 748 return; 749 } 750 msglog("write(rt_sock)" PAT ": %s", ARGS, strerror(errno)); 751 return; 752 } else if (cc != w.w_rtm.rtm_msglen) { 753 msglog("write(rt_sock) wrote %ld instead of %d for" PAT, 754 cc, w.w_rtm.rtm_msglen, ARGS); 755 return; 756 } 757 #endif 758 if (TRACEKERNEL) 759 trace_misc("write kernel" PAT, ARGS); 760 #undef PAT 761 #undef ARGS 762 } 763 764 765 #define KHASH_SIZE 71 /* should be prime */ 766 #define KHASH(a,m) khash_bins[((a) ^ (m)) % KHASH_SIZE] 767 static struct khash { 768 struct khash *k_next; 769 naddr k_dst; 770 naddr k_mask; 771 naddr k_gate; 772 short k_metric; 773 u_short k_state; 774 #define KS_NEW 0x001 775 #define KS_DELETE 0x002 /* need to delete the route */ 776 #define KS_ADD 0x004 /* add to the kernel */ 777 #define KS_CHANGE 0x008 /* tell kernel to change the route */ 778 #define KS_DEL_ADD 0x010 /* delete & add to change the kernel */ 779 #define KS_STATIC 0x020 /* Static flag in kernel */ 780 #define KS_GATEWAY 0x040 /* G flag in kernel */ 781 #define KS_DYNAMIC 0x080 /* result of redirect */ 782 #define KS_DELETED 0x100 /* already deleted from kernel */ 783 #define KS_CHECK 0x200 784 time_t k_keep; 785 #define K_KEEP_LIM 30 786 time_t k_redirect_time; /* when redirected route 1st seen */ 787 } *khash_bins[KHASH_SIZE]; 788 789 790 static struct khash* 791 kern_find(naddr dst, naddr mask, struct khash ***ppk) 792 { 793 struct khash *k, **pk; 794 795 for (pk = &KHASH(dst,mask); (k = *pk) != NULL; pk = &k->k_next) { 796 if (k->k_dst == dst && k->k_mask == mask) 797 break; 798 } 799 if (ppk != NULL) 800 *ppk = pk; 801 return k; 802 } 803 804 805 static struct khash* 806 kern_add(naddr dst, naddr mask) 807 { 808 struct khash *k, **pk; 809 810 k = kern_find(dst, mask, &pk); 811 if (k != NULL) 812 return k; 813 814 k = (struct khash *)rtmalloc(sizeof(*k), "kern_add"); 815 816 memset(k, 0, sizeof(*k)); 817 k->k_dst = dst; 818 k->k_mask = mask; 819 k->k_state = KS_NEW; 820 k->k_keep = now.tv_sec; 821 *pk = k; 822 823 return k; 824 } 825 826 827 /* If a kernel route has a non-zero metric, check that it is still in the 828 * daemon table, and not deleted by interfaces coming and going. 829 */ 830 static void 831 kern_check_static(struct khash *k, 832 struct interface *ifp) 833 { 834 struct rt_entry *rt; 835 struct rt_spare new; 836 837 if (k->k_metric == 0) 838 return; 839 840 memset(&new, 0, sizeof(new)); 841 new.rts_ifp = ifp; 842 new.rts_gate = k->k_gate; 843 new.rts_router = (ifp != NULL) ? ifp->int_addr : loopaddr; 844 new.rts_metric = k->k_metric; 845 new.rts_time = now.tv_sec; 846 847 rt = rtget(k->k_dst, k->k_mask); 848 if (rt != NULL) { 849 if (!(rt->rt_state & RS_STATIC)) 850 rtchange(rt, rt->rt_state | RS_STATIC, &new, 0); 851 } else { 852 rtadd(k->k_dst, k->k_mask, RS_STATIC, &new); 853 } 854 } 855 856 857 /* operate on a kernel entry 858 */ 859 static void 860 kern_ioctl(struct khash *k, 861 int action, /* RTM_DELETE, etc */ 862 int flags) 863 864 { 865 switch (action) { 866 case RTM_DELETE: 867 k->k_state &= ~KS_DYNAMIC; 868 if (k->k_state & KS_DELETED) 869 return; 870 k->k_state |= KS_DELETED; 871 break; 872 case RTM_ADD: 873 k->k_state &= ~KS_DELETED; 874 break; 875 case RTM_CHANGE: 876 if (k->k_state & KS_DELETED) { 877 action = RTM_ADD; 878 k->k_state &= ~KS_DELETED; 879 } 880 break; 881 } 882 883 rtioctl(action, k->k_dst, k->k_gate, k->k_mask, k->k_metric, flags); 884 } 885 886 887 /* add a route the kernel told us 888 */ 889 static void 890 rtm_add(struct rt_msghdr *rtm, 891 struct rt_addrinfo *info, 892 time_t keep) 893 { 894 struct khash *k; 895 struct interface *ifp; 896 naddr mask; 897 898 899 if (rtm->rtm_flags & RTF_HOST) { 900 mask = HOST_MASK; 901 } else if (INFO_MASK(info) != 0) { 902 mask = ntohl(S_ADDR(INFO_MASK(info))); 903 } else { 904 msglog("ignore %s without mask", rtm_type_name(rtm->rtm_type)); 905 return; 906 } 907 908 k = kern_add(S_ADDR(INFO_DST(info)), mask); 909 if (k->k_state & KS_NEW) 910 k->k_keep = now.tv_sec+keep; 911 if (INFO_GATE(info) == 0) { 912 trace_act("note %s without gateway", 913 rtm_type_name(rtm->rtm_type)); 914 k->k_metric = HOPCNT_INFINITY; 915 } else if (INFO_GATE(info)->sa_family != AF_INET) { 916 trace_act("note %s with gateway AF=%d", 917 rtm_type_name(rtm->rtm_type), 918 INFO_GATE(info)->sa_family); 919 k->k_metric = HOPCNT_INFINITY; 920 } else { 921 k->k_gate = S_ADDR(INFO_GATE(info)); 922 k->k_metric = rtm->rtm_rmx.rmx_hopcount; 923 if (k->k_metric < 0) 924 k->k_metric = 0; 925 else if (k->k_metric > HOPCNT_INFINITY-1) 926 k->k_metric = HOPCNT_INFINITY-1; 927 } 928 k->k_state &= ~(KS_DELETE | KS_ADD | KS_CHANGE | KS_DEL_ADD 929 | KS_DELETED | KS_GATEWAY | KS_STATIC 930 | KS_NEW | KS_CHECK); 931 if (rtm->rtm_flags & RTF_GATEWAY) 932 k->k_state |= KS_GATEWAY; 933 if (rtm->rtm_flags & RTF_STATIC) 934 k->k_state |= KS_STATIC; 935 936 if (0 != (rtm->rtm_flags & (RTF_DYNAMIC | RTF_MODIFIED))) { 937 if (INFO_AUTHOR(info) != 0 938 && INFO_AUTHOR(info)->sa_family == AF_INET) 939 ifp = iflookup(S_ADDR(INFO_AUTHOR(info))); 940 else 941 ifp = NULL; 942 if (supplier 943 && (ifp == NULL || !(ifp->int_state & IS_REDIRECT_OK))) { 944 /* Routers are not supposed to listen to redirects, 945 * so delete it if it came via an unknown interface 946 * or the interface does not have special permission. 947 */ 948 k->k_state &= ~KS_DYNAMIC; 949 k->k_state |= KS_DELETE; 950 LIM_SEC(need_kern, 0); 951 trace_act("mark for deletion redirected %s --> %s" 952 " 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 } else { 957 k->k_state |= KS_DYNAMIC; 958 k->k_redirect_time = now.tv_sec; 959 trace_act("accept redirected %s --> %s via %s", 960 addrname(k->k_dst, k->k_mask, 0), 961 naddr_ntoa(k->k_gate), 962 ifp ? ifp->int_name : "unknown interface"); 963 } 964 return; 965 } 966 967 /* If it is not a static route, quit until the next comparison 968 * between the kernel and daemon tables, when it will be deleted. 969 */ 970 if (!(k->k_state & KS_STATIC)) { 971 k->k_state |= KS_DELETE; 972 LIM_SEC(need_kern, k->k_keep); 973 return; 974 } 975 976 /* Put static routes with real metrics into the daemon table so 977 * they can be advertised. 978 * 979 * Find the interface toward the gateway. 980 */ 981 ifp = iflookup(k->k_gate); 982 if (ifp == NULL) 983 msglog("static route %s --> %s impossibly lacks ifp", 984 addrname(S_ADDR(INFO_DST(info)), mask, 0), 985 naddr_ntoa(k->k_gate)); 986 987 kern_check_static(k, ifp); 988 } 989 990 991 /* deal with packet loss 992 */ 993 static void 994 rtm_lose(struct rt_msghdr *rtm, 995 struct rt_addrinfo *info) 996 { 997 if (INFO_GATE(info) == 0 998 || INFO_GATE(info)->sa_family != AF_INET) { 999 trace_act("ignore %s without gateway", 1000 rtm_type_name(rtm->rtm_type)); 1001 return; 1002 } 1003 1004 if (rdisc_ok) 1005 rdisc_age(S_ADDR(INFO_GATE(info))); 1006 age(S_ADDR(INFO_GATE(info))); 1007 } 1008 1009 1010 /* Make the gateway slot of an info structure point to something 1011 * useful. If it is not already useful, but it specifies an interface, 1012 * then fill in the sockaddr_in provided and point it there. 1013 */ 1014 static int 1015 get_info_gate(struct sockaddr **sap, 1016 struct sockaddr_in *in) 1017 { 1018 struct sockaddr_dl *sdl = (struct sockaddr_dl *)*sap; 1019 struct interface *ifp; 1020 1021 if (sdl == NULL) 1022 return 0; 1023 if ((sdl)->sdl_family == AF_INET) 1024 return 1; 1025 if ((sdl)->sdl_family != AF_LINK) 1026 return 0; 1027 1028 ifp = ifwithindex(sdl->sdl_index, 1); 1029 if (ifp == NULL) 1030 return 0; 1031 1032 in->sin_addr.s_addr = ifp->int_addr; 1033 #ifdef _HAVE_SA_LEN 1034 in->sin_len = sizeof(*in); 1035 #endif 1036 in->sin_family = AF_INET; 1037 *sap = (struct sockaddr *)in; 1038 1039 return 1; 1040 } 1041 1042 1043 /* Clean the kernel table by copying it to the daemon image. 1044 * Eventually the daemon will delete any extra routes. 1045 */ 1046 void 1047 flush_kern(void) 1048 { 1049 static char *sysctl_buf; 1050 static size_t sysctl_buf_size = 0; 1051 size_t needed; 1052 int mib[6]; 1053 char *next, *lim; 1054 struct rt_msghdr *rtm; 1055 struct sockaddr_in gate_sin; 1056 struct rt_addrinfo info; 1057 int i; 1058 struct khash *k; 1059 1060 1061 for (i = 0; i < KHASH_SIZE; i++) { 1062 for (k = khash_bins[i]; k != NULL; k = k->k_next) { 1063 k->k_state |= KS_CHECK; 1064 } 1065 } 1066 1067 mib[0] = CTL_NET; 1068 mib[1] = PF_ROUTE; 1069 mib[2] = 0; /* protocol */ 1070 mib[3] = 0; /* wildcard address family */ 1071 mib[4] = NET_RT_DUMP; 1072 mib[5] = 0; /* no flags */ 1073 for (;;) { 1074 if ((needed = sysctl_buf_size) != 0) { 1075 if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0) 1076 break; 1077 if (errno != ENOMEM && errno != EFAULT) 1078 BADERR(1,"flush_kern: sysctl(RT_DUMP)"); 1079 free(sysctl_buf); 1080 needed = 0; 1081 } 1082 if (sysctl(mib, 6, 0, &needed, 0, 0) < 0) 1083 BADERR(1,"flush_kern: sysctl(RT_DUMP) estimate"); 1084 /* Kludge around the habit of some systems, such as 1085 * BSD/OS 3.1, to not admit how many routes are in the 1086 * kernel, or at least to be quite wrong. 1087 */ 1088 needed += 50*(sizeof(*rtm)+5*sizeof(struct sockaddr)); 1089 sysctl_buf = rtmalloc(sysctl_buf_size = needed, 1090 "flush_kern sysctl(RT_DUMP)"); 1091 } 1092 1093 lim = sysctl_buf + needed; 1094 for (next = sysctl_buf; next < lim; next += rtm->rtm_msglen) { 1095 rtm = (struct rt_msghdr *)next; 1096 if (rtm->rtm_msglen == 0) { 1097 msglog("zero length kernel route at " 1098 " %#lx in buffer %#lx before %#lx", 1099 (u_long)rtm, (u_long)sysctl_buf, (u_long)lim); 1100 break; 1101 } 1102 1103 rt_xaddrs(&info, 1104 (struct sockaddr *)(rtm+1), 1105 (struct sockaddr *)(next + rtm->rtm_msglen), 1106 rtm->rtm_addrs); 1107 1108 if (INFO_DST(&info) == 0 1109 || INFO_DST(&info)->sa_family != AF_INET) 1110 continue; 1111 1112 /* ignore ARP table entries on systems with a merged route 1113 * and ARP table. 1114 */ 1115 if (rtm->rtm_flags & RTF_LLINFO) 1116 continue; 1117 1118 /* ignore multicast addresses 1119 */ 1120 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) 1121 continue; 1122 1123 if (!get_info_gate(&INFO_GATE(&info), &gate_sin)) 1124 continue; 1125 1126 /* Note static routes and interface routes, and also 1127 * preload the image of the kernel table so that 1128 * we can later clean it, as well as avoid making 1129 * unneeded changes. Keep the old kernel routes for a 1130 * few seconds to allow a RIP or router-discovery 1131 * response to be heard. 1132 */ 1133 rtm_add(rtm,&info,MIN_WAITTIME); 1134 } 1135 1136 for (i = 0; i < KHASH_SIZE; i++) { 1137 for (k = khash_bins[i]; k != NULL; k = k->k_next) { 1138 if (k->k_state & KS_CHECK) { 1139 msglog("%s --> %s disappeared from kernel", 1140 addrname(k->k_dst, k->k_mask, 0), 1141 naddr_ntoa(k->k_gate)); 1142 del_static(k->k_dst, k->k_mask, k->k_gate, 1); 1143 } 1144 } 1145 } 1146 } 1147 1148 1149 /* Listen to announcements from the kernel 1150 */ 1151 void 1152 read_rt(void) 1153 { 1154 long cc; 1155 struct interface *ifp; 1156 struct sockaddr_in gate_sin; 1157 naddr mask, gate; 1158 union { 1159 struct { 1160 struct rt_msghdr rtm; 1161 struct sockaddr addrs[RTAX_MAX]; 1162 } r; 1163 struct if_msghdr ifm; 1164 } m; 1165 char str[100], *strp; 1166 struct rt_addrinfo info; 1167 1168 1169 for (;;) { 1170 cc = read(rt_sock, &m, sizeof(m)); 1171 if (cc <= 0) { 1172 if (cc < 0 && errno != EWOULDBLOCK) 1173 LOGERR("read(rt_sock)"); 1174 return; 1175 } 1176 1177 if (m.r.rtm.rtm_version != RTM_VERSION) { 1178 msglog("bogus routing message version %d", 1179 m.r.rtm.rtm_version); 1180 continue; 1181 } 1182 1183 /* Ignore our own results. 1184 */ 1185 if (m.r.rtm.rtm_type <= RTM_CHANGE 1186 && m.r.rtm.rtm_pid == mypid) { 1187 static int complained = 0; 1188 if (!complained) { 1189 msglog("receiving our own change messages"); 1190 complained = 1; 1191 } 1192 continue; 1193 } 1194 1195 if (m.r.rtm.rtm_type == RTM_IFINFO 1196 || m.r.rtm.rtm_type == RTM_NEWADDR 1197 || m.r.rtm.rtm_type == RTM_DELADDR) { 1198 ifp = ifwithindex(m.ifm.ifm_index, 1199 m.r.rtm.rtm_type != RTM_DELADDR); 1200 if (ifp == NULL) 1201 trace_act("note %s with flags %#x" 1202 " for unknown interface index #%d", 1203 rtm_type_name(m.r.rtm.rtm_type), 1204 m.ifm.ifm_flags, 1205 m.ifm.ifm_index); 1206 else 1207 trace_act("note %s with flags %#x for %s", 1208 rtm_type_name(m.r.rtm.rtm_type), 1209 m.ifm.ifm_flags, 1210 ifp->int_name); 1211 1212 /* After being informed of a change to an interface, 1213 * check them all now if the check would otherwise 1214 * be a long time from now, if the interface is 1215 * not known, or if the interface has been turned 1216 * off or on. 1217 */ 1218 if (ifinit_timer.tv_sec-now.tv_sec>=CHECK_BAD_INTERVAL 1219 || ifp == NULL 1220 || ((ifp->int_if_flags ^ m.ifm.ifm_flags) 1221 & IFF_UP) != 0) 1222 ifinit_timer.tv_sec = now.tv_sec; 1223 continue; 1224 } 1225 1226 strcpy(str, rtm_type_name(m.r.rtm.rtm_type)); 1227 strp = &str[strlen(str)]; 1228 if (m.r.rtm.rtm_type <= RTM_CHANGE) 1229 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid); 1230 1231 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX], 1232 m.r.rtm.rtm_addrs); 1233 1234 if (INFO_DST(&info) == 0) { 1235 trace_act("ignore %s without dst", str); 1236 continue; 1237 } 1238 1239 if (INFO_DST(&info)->sa_family != AF_INET) { 1240 trace_act("ignore %s for AF %d", str, 1241 INFO_DST(&info)->sa_family); 1242 continue; 1243 } 1244 1245 mask = ((INFO_MASK(&info) != 0) 1246 ? ntohl(S_ADDR(INFO_MASK(&info))) 1247 : (m.r.rtm.rtm_flags & RTF_HOST) 1248 ? HOST_MASK 1249 : std_mask(S_ADDR(INFO_DST(&info)))); 1250 1251 strp += sprintf(strp, ": %s", 1252 addrname(S_ADDR(INFO_DST(&info)), mask, 0)); 1253 1254 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) { 1255 trace_act("ignore multicast %s", str); 1256 continue; 1257 } 1258 1259 if (m.r.rtm.rtm_flags & RTF_LLINFO) { 1260 trace_act("ignore ARP %s", str); 1261 continue; 1262 } 1263 1264 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) { 1265 gate = S_ADDR(INFO_GATE(&info)); 1266 strp += sprintf(strp, " --> %s", naddr_ntoa(gate)); 1267 } else { 1268 gate = 0; 1269 } 1270 1271 if (INFO_AUTHOR(&info) != 0) 1272 strp += sprintf(strp, " by authority of %s", 1273 saddr_ntoa(INFO_AUTHOR(&info))); 1274 1275 switch (m.r.rtm.rtm_type) { 1276 case RTM_ADD: 1277 case RTM_CHANGE: 1278 case RTM_REDIRECT: 1279 if (m.r.rtm.rtm_errno != 0) { 1280 trace_act("ignore %s with \"%s\" error", 1281 str, strerror(m.r.rtm.rtm_errno)); 1282 } else { 1283 trace_act("%s", str); 1284 rtm_add(&m.r.rtm,&info,0); 1285 } 1286 break; 1287 1288 case RTM_DELETE: 1289 if (m.r.rtm.rtm_errno != 0 1290 && m.r.rtm.rtm_errno != ESRCH) { 1291 trace_act("ignore %s with \"%s\" error", 1292 str, strerror(m.r.rtm.rtm_errno)); 1293 } else { 1294 trace_act("%s", str); 1295 del_static(S_ADDR(INFO_DST(&info)), mask, 1296 gate, 1); 1297 } 1298 break; 1299 1300 case RTM_LOSING: 1301 trace_act("%s", str); 1302 rtm_lose(&m.r.rtm,&info); 1303 break; 1304 1305 default: 1306 trace_act("ignore %s", str); 1307 break; 1308 } 1309 } 1310 } 1311 1312 1313 /* after aggregating, note routes that belong in the kernel 1314 */ 1315 static void 1316 kern_out(struct ag_info *ag) 1317 { 1318 struct khash *k; 1319 1320 1321 /* Do not install bad routes if they are not already present. 1322 * This includes routes that had RS_NET_SYN for interfaces that 1323 * recently died. 1324 */ 1325 if (ag->ag_metric == HOPCNT_INFINITY) { 1326 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0); 1327 if (k == NULL) 1328 return; 1329 } else { 1330 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask); 1331 } 1332 1333 if (k->k_state & KS_NEW) { 1334 /* will need to add new entry to the kernel table */ 1335 k->k_state = KS_ADD; 1336 if (ag->ag_state & AGS_GATEWAY) 1337 k->k_state |= KS_GATEWAY; 1338 k->k_gate = ag->ag_gate; 1339 k->k_metric = ag->ag_metric; 1340 return; 1341 } 1342 1343 if (k->k_state & KS_STATIC) 1344 return; 1345 1346 /* modify existing kernel entry if necessary */ 1347 if (k->k_gate != ag->ag_gate 1348 || k->k_metric != ag->ag_metric) { 1349 /* Must delete bad interface routes etc. to change them. */ 1350 if (k->k_metric == HOPCNT_INFINITY) 1351 k->k_state |= KS_DEL_ADD; 1352 k->k_gate = ag->ag_gate; 1353 k->k_metric = ag->ag_metric; 1354 k->k_state |= KS_CHANGE; 1355 } 1356 1357 /* If the daemon thinks the route should exist, forget 1358 * about any redirections. 1359 * If the daemon thinks the route should exist, eventually 1360 * override manual intervention by the operator. 1361 */ 1362 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) { 1363 k->k_state &= ~KS_DYNAMIC; 1364 k->k_state |= (KS_ADD | KS_DEL_ADD); 1365 } 1366 1367 if ((k->k_state & KS_GATEWAY) 1368 && !(ag->ag_state & AGS_GATEWAY)) { 1369 k->k_state &= ~KS_GATEWAY; 1370 k->k_state |= (KS_ADD | KS_DEL_ADD); 1371 } else if (!(k->k_state & KS_GATEWAY) 1372 && (ag->ag_state & AGS_GATEWAY)) { 1373 k->k_state |= KS_GATEWAY; 1374 k->k_state |= (KS_ADD | KS_DEL_ADD); 1375 } 1376 1377 /* Deleting-and-adding is necessary to change aspects of a route. 1378 * Just delete instead of deleting and then adding a bad route. 1379 * Otherwise, we want to keep the route in the kernel. 1380 */ 1381 if (k->k_metric == HOPCNT_INFINITY 1382 && (k->k_state & KS_DEL_ADD)) 1383 k->k_state |= KS_DELETE; 1384 else 1385 k->k_state &= ~KS_DELETE; 1386 #undef RT 1387 } 1388 1389 1390 /* ARGSUSED */ 1391 static int 1392 walk_kern(struct radix_node *rn, 1393 struct walkarg *argp UNUSED) 1394 { 1395 #define RT ((struct rt_entry *)rn) 1396 char metric, pref; 1397 u_int ags = 0; 1398 1399 1400 /* Do not install synthetic routes */ 1401 if (RT->rt_state & RS_NET_SYN) 1402 return 0; 1403 1404 if (!(RT->rt_state & RS_IF)) { 1405 /* This is an ordinary route, not for an interface. 1406 */ 1407 1408 /* aggregate, ordinary good routes without regard to 1409 * their metric 1410 */ 1411 pref = 1; 1412 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1413 1414 /* Do not install host routes directly to hosts, to avoid 1415 * interfering with ARP entries in the kernel table. 1416 */ 1417 if (RT_ISHOST(RT) 1418 && ntohl(RT->rt_dst) == RT->rt_gate) 1419 return 0; 1420 1421 } else { 1422 /* This is an interface route. 1423 * Do not install routes for "external" remote interfaces. 1424 */ 1425 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL)) 1426 return 0; 1427 1428 /* Interfaces should override received routes. 1429 */ 1430 pref = 0; 1431 ags |= (AGS_IF | AGS_CORS_GATE); 1432 1433 /* If it is not an interface, or an alias for an interface, 1434 * it must be a "gateway." 1435 * 1436 * If it is a "remote" interface, it is also a "gateway" to 1437 * the kernel if is not a alias. 1438 */ 1439 if (RT->rt_ifp == 0 1440 || (RT->rt_ifp->int_state & IS_REMOTE)) 1441 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1442 } 1443 1444 /* If RIP is off and IRDP is on, let the route to the discovered 1445 * route suppress any RIP routes. Eventually the RIP routes 1446 * will time-out and be deleted. This reaches the steady-state 1447 * quicker. 1448 */ 1449 if ((RT->rt_state & RS_RDISC) && rip_sock < 0) 1450 ags |= AGS_CORS_GATE; 1451 1452 metric = RT->rt_metric; 1453 if (metric == HOPCNT_INFINITY) { 1454 /* if the route is dead, so try hard to aggregate. */ 1455 pref = HOPCNT_INFINITY; 1456 ags |= (AGS_FINE_GATE | AGS_SUPPRESS); 1457 ags &= ~(AGS_IF | AGS_CORS_GATE); 1458 } 1459 1460 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0, 1461 metric,pref, 0, 0, ags, kern_out); 1462 return 0; 1463 #undef RT 1464 } 1465 1466 1467 /* Update the kernel table to match the daemon table. 1468 */ 1469 static void 1470 fix_kern(void) 1471 { 1472 int i; 1473 struct khash *k, **pk; 1474 1475 1476 need_kern = age_timer; 1477 1478 /* Walk daemon table, updating the copy of the kernel table. 1479 */ 1480 rn_walktree(rhead, walk_kern, 0); 1481 ag_flush(0,0,kern_out); 1482 1483 for (i = 0; i < KHASH_SIZE; i++) { 1484 for (pk = &khash_bins[i]; (k = *pk) != NULL; ) { 1485 /* Do not touch static routes */ 1486 if (k->k_state & KS_STATIC) { 1487 kern_check_static(k,0); 1488 pk = &k->k_next; 1489 continue; 1490 } 1491 1492 /* check hold on routes deleted by the operator */ 1493 if (k->k_keep > now.tv_sec) { 1494 /* ensure we check when the hold is over */ 1495 LIM_SEC(need_kern, k->k_keep); 1496 /* mark for the next cycle */ 1497 k->k_state |= KS_DELETE; 1498 pk = &k->k_next; 1499 continue; 1500 } 1501 1502 if ((k->k_state & KS_DELETE) 1503 && !(k->k_state & KS_DYNAMIC)) { 1504 kern_ioctl(k, RTM_DELETE, 0); 1505 *pk = k->k_next; 1506 free(k); 1507 continue; 1508 } 1509 1510 if (k->k_state & KS_DEL_ADD) 1511 kern_ioctl(k, RTM_DELETE, 0); 1512 1513 if (k->k_state & KS_ADD) { 1514 kern_ioctl(k, RTM_ADD, 1515 ((0 != (k->k_state & (KS_GATEWAY 1516 | KS_DYNAMIC))) 1517 ? RTF_GATEWAY : 0)); 1518 } else if (k->k_state & KS_CHANGE) { 1519 kern_ioctl(k, RTM_CHANGE, 1520 ((0 != (k->k_state & (KS_GATEWAY 1521 | KS_DYNAMIC))) 1522 ? RTF_GATEWAY : 0)); 1523 } 1524 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD); 1525 1526 /* Mark this route to be deleted in the next cycle. 1527 * This deletes routes that disappear from the 1528 * daemon table, since the normal aging code 1529 * will clear the bit for routes that have not 1530 * disappeared from the daemon table. 1531 */ 1532 k->k_state |= KS_DELETE; 1533 pk = &k->k_next; 1534 } 1535 } 1536 } 1537 1538 1539 /* Delete a static route in the image of the kernel table. 1540 */ 1541 void 1542 del_static(naddr dst, 1543 naddr mask, 1544 naddr gate, 1545 int gone) 1546 { 1547 struct khash *k; 1548 struct rt_entry *rt; 1549 1550 /* Just mark it in the table to be deleted next time the kernel 1551 * table is updated. 1552 * If it has already been deleted, mark it as such, and set its 1553 * keep-timer so that it will not be deleted again for a while. 1554 * This lets the operator delete a route added by the daemon 1555 * and add a replacement. 1556 */ 1557 k = kern_find(dst, mask, 0); 1558 if (k != NULL && (gate == 0 || k->k_gate == gate)) { 1559 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK); 1560 k->k_state |= KS_DELETE; 1561 if (gone) { 1562 k->k_state |= KS_DELETED; 1563 k->k_keep = now.tv_sec + K_KEEP_LIM; 1564 } 1565 } 1566 1567 rt = rtget(dst, mask); 1568 if (rt != NULL && (rt->rt_state & RS_STATIC)) 1569 rtbad(rt); 1570 } 1571 1572 1573 /* Delete all routes generated from ICMP Redirects that use a given gateway, 1574 * as well as old redirected routes. 1575 */ 1576 void 1577 del_redirects(naddr bad_gate, 1578 time_t old) 1579 { 1580 int i; 1581 struct khash *k; 1582 1583 1584 for (i = 0; i < KHASH_SIZE; i++) { 1585 for (k = khash_bins[i]; k != NULL; k = k->k_next) { 1586 if (!(k->k_state & KS_DYNAMIC) 1587 || (k->k_state & KS_STATIC)) 1588 continue; 1589 1590 if (k->k_gate != bad_gate 1591 && k->k_redirect_time > old 1592 && !supplier) 1593 continue; 1594 1595 k->k_state |= KS_DELETE; 1596 k->k_state &= ~KS_DYNAMIC; 1597 need_kern.tv_sec = now.tv_sec; 1598 trace_act("mark redirected %s --> %s for deletion", 1599 addrname(k->k_dst, k->k_mask, 0), 1600 naddr_ntoa(k->k_gate)); 1601 } 1602 } 1603 } 1604 1605 1606 /* Start the daemon tables. 1607 */ 1608 extern int max_keylen; 1609 1610 void 1611 rtinit(void) 1612 { 1613 int i; 1614 struct ag_info *ag; 1615 1616 /* Initialize the radix trees */ 1617 max_keylen = sizeof(struct sockaddr_in); 1618 rn_init(); 1619 rn_inithead(&rhead, 32); 1620 1621 /* mark all of the slots in the table free */ 1622 ag_avail = ag_slots; 1623 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) { 1624 ag->ag_fine = ag+1; 1625 ag++; 1626 } 1627 } 1628 1629 1630 #ifdef _HAVE_SIN_LEN 1631 static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET, 0, {0}, {0}}; 1632 static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET, 0, {0}, {0}}; 1633 #else 1634 static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET}; 1635 static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET}; 1636 #endif 1637 1638 1639 static void 1640 set_need_flash(void) 1641 { 1642 if (!need_flash) { 1643 need_flash = 1; 1644 /* Do not send the flash update immediately. Wait a little 1645 * while to hear from other routers. 1646 */ 1647 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME; 1648 } 1649 } 1650 1651 1652 /* Get a particular routing table entry 1653 */ 1654 struct rt_entry * 1655 rtget(naddr dst, naddr mask) 1656 { 1657 struct rt_entry *rt; 1658 1659 dst_sock.sin_addr.s_addr = dst; 1660 mask_sock.sin_addr.s_addr = htonl(mask); 1661 masktrim(&mask_sock); 1662 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead); 1663 if (!rt 1664 || rt->rt_dst != dst 1665 || rt->rt_mask != mask) 1666 return 0; 1667 1668 return rt; 1669 } 1670 1671 1672 /* Find a route to dst as the kernel would. 1673 */ 1674 struct rt_entry * 1675 rtfind(naddr dst) 1676 { 1677 dst_sock.sin_addr.s_addr = dst; 1678 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead); 1679 } 1680 1681 1682 /* add a route to the table 1683 */ 1684 void 1685 rtadd(naddr dst, 1686 naddr mask, 1687 u_int state, /* rt_state for the entry */ 1688 struct rt_spare *new) 1689 { 1690 struct rt_entry *rt; 1691 naddr smask; 1692 int i; 1693 struct rt_spare *rts; 1694 1695 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd"); 1696 memset(rt, 0, sizeof(*rt)); 1697 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) 1698 rts->rts_metric = HOPCNT_INFINITY; 1699 1700 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock; 1701 rt->rt_dst = dst; 1702 rt->rt_dst_sock.sin_family = AF_INET; 1703 #ifdef _HAVE_SIN_LEN 1704 rt->rt_dst_sock.sin_len = dst_sock.sin_len; 1705 #endif 1706 if (mask != HOST_MASK) { 1707 smask = std_mask(dst); 1708 if ((smask & ~mask) == 0 && mask > smask) 1709 state |= RS_SUBNET; 1710 } 1711 mask_sock.sin_addr.s_addr = htonl(mask); 1712 masktrim(&mask_sock); 1713 rt->rt_mask = mask; 1714 rt->rt_state = state; 1715 rt->rt_spares[0] = *new; 1716 rt->rt_time = now.tv_sec; 1717 rt->rt_poison_metric = HOPCNT_INFINITY; 1718 rt->rt_seqno = update_seqno; 1719 1720 if (++total_routes == MAX_ROUTES) 1721 msglog("have maximum (%d) routes", total_routes); 1722 if (TRACEACTIONS) 1723 trace_add_del("Add", rt); 1724 1725 need_kern.tv_sec = now.tv_sec; 1726 set_need_flash(); 1727 1728 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock, 1729 rhead, rt->rt_nodes)) { 1730 msglog("rnh_addaddr() failed for %s mask=%#lx", 1731 naddr_ntoa(dst), (u_long)mask); 1732 free(rt); 1733 } 1734 } 1735 1736 1737 /* notice a changed route 1738 */ 1739 void 1740 rtchange(struct rt_entry *rt, 1741 u_int state, /* new state bits */ 1742 struct rt_spare *new, 1743 char *label) 1744 { 1745 if (rt->rt_metric != new->rts_metric) { 1746 /* Fix the kernel immediately if it seems the route 1747 * has gone bad, since there may be a working route that 1748 * aggregates this route. 1749 */ 1750 if (new->rts_metric == HOPCNT_INFINITY) { 1751 need_kern.tv_sec = now.tv_sec; 1752 if (new->rts_time >= now.tv_sec - EXPIRE_TIME) 1753 new->rts_time = now.tv_sec - EXPIRE_TIME; 1754 } 1755 rt->rt_seqno = update_seqno; 1756 set_need_flash(); 1757 } 1758 1759 if (rt->rt_gate != new->rts_gate) { 1760 need_kern.tv_sec = now.tv_sec; 1761 rt->rt_seqno = update_seqno; 1762 set_need_flash(); 1763 } 1764 1765 state |= (rt->rt_state & RS_SUBNET); 1766 1767 /* Keep various things from deciding ageless routes are stale. 1768 */ 1769 if (!AGE_RT(state, new->rts_ifp)) 1770 new->rts_time = now.tv_sec; 1771 1772 if (TRACEACTIONS) 1773 trace_change(rt, state, new, 1774 label ? label : "Chg "); 1775 1776 rt->rt_state = state; 1777 rt->rt_spares[0] = *new; 1778 } 1779 1780 1781 /* check for a better route among the spares 1782 */ 1783 static struct rt_spare * 1784 rts_better(struct rt_entry *rt) 1785 { 1786 struct rt_spare *rts, *rts1; 1787 int i; 1788 1789 /* find the best alternative among the spares */ 1790 rts = rt->rt_spares+1; 1791 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) { 1792 if (BETTER_LINK(rt,rts1,rts)) 1793 rts = rts1; 1794 } 1795 1796 return rts; 1797 } 1798 1799 1800 /* switch to a backup route 1801 */ 1802 void 1803 rtswitch(struct rt_entry *rt, 1804 struct rt_spare *rts) 1805 { 1806 struct rt_spare swap; 1807 char label[10]; 1808 1809 1810 /* Do not change permanent routes */ 1811 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC 1812 | RS_NET_SYN | RS_IF))) 1813 return; 1814 1815 /* find the best alternative among the spares */ 1816 if (rts == NULL) 1817 rts = rts_better(rt); 1818 1819 /* Do not bother if it is not worthwhile. 1820 */ 1821 if (!BETTER_LINK(rt, rts, rt->rt_spares)) 1822 return; 1823 1824 swap = rt->rt_spares[0]; 1825 sprintf(label, "Use #%d", (int)(rts - rt->rt_spares)); 1826 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label); 1827 if (swap.rts_metric == HOPCNT_INFINITY) { 1828 *rts = rts_empty; 1829 } else { 1830 *rts = swap; 1831 } 1832 } 1833 1834 1835 void 1836 rtdelete(struct rt_entry *rt) 1837 { 1838 struct khash *k; 1839 1840 1841 if (TRACEACTIONS) 1842 trace_add_del("Del", rt); 1843 1844 k = kern_find(rt->rt_dst, rt->rt_mask, 0); 1845 if (k != NULL) { 1846 k->k_state |= KS_DELETE; 1847 need_kern.tv_sec = now.tv_sec; 1848 } 1849 1850 dst_sock.sin_addr.s_addr = rt->rt_dst; 1851 mask_sock.sin_addr.s_addr = htonl(rt->rt_mask); 1852 masktrim(&mask_sock); 1853 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock, 1854 rhead)) { 1855 msglog("rnh_deladdr() failed"); 1856 } else { 1857 free(rt); 1858 total_routes--; 1859 } 1860 } 1861 1862 1863 void 1864 rts_delete(struct rt_entry *rt, 1865 struct rt_spare *rts) 1866 { 1867 trace_upslot(rt, rts, &rts_empty); 1868 *rts = rts_empty; 1869 } 1870 1871 1872 /* Get rid of a bad route, and try to switch to a replacement. 1873 */ 1874 void 1875 rtbad(struct rt_entry *rt) 1876 { 1877 struct rt_spare new; 1878 1879 /* Poison the route */ 1880 new = rt->rt_spares[0]; 1881 new.rts_metric = HOPCNT_INFINITY; 1882 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0); 1883 rtswitch(rt, 0); 1884 } 1885 1886 1887 /* Junk a RS_NET_SYN or RS_LOCAL route, 1888 * unless it is needed by another interface. 1889 */ 1890 void 1891 rtbad_sub(struct rt_entry *rt) 1892 { 1893 struct interface *ifp, *ifp1; 1894 struct intnet *intnetp; 1895 u_int state; 1896 1897 1898 ifp1 = NULL; 1899 state = 0; 1900 1901 if (rt->rt_state & RS_LOCAL) { 1902 /* Is this the route through loopback for the interface? 1903 * If so, see if it is used by any other interfaces, such 1904 * as a point-to-point interface with the same local address. 1905 */ 1906 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) { 1907 /* Retain it if another interface needs it. 1908 */ 1909 if (ifp->int_addr == rt->rt_ifp->int_addr) { 1910 state |= RS_LOCAL; 1911 ifp1 = ifp; 1912 break; 1913 } 1914 } 1915 1916 } 1917 1918 if (!(state & RS_LOCAL)) { 1919 /* Retain RIPv1 logical network route if there is another 1920 * interface that justifies it. 1921 */ 1922 if (rt->rt_state & RS_NET_SYN) { 1923 for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) { 1924 if ((ifp->int_state & IS_NEED_NET_SYN) 1925 && rt->rt_mask == ifp->int_std_mask 1926 && rt->rt_dst == ifp->int_std_addr) { 1927 state |= RS_NET_SYN; 1928 ifp1 = ifp; 1929 break; 1930 } 1931 } 1932 } 1933 1934 /* or if there is an authority route that needs it. */ 1935 for (intnetp = intnets; 1936 intnetp != NULL; 1937 intnetp = intnetp->intnet_next) { 1938 if (intnetp->intnet_addr == rt->rt_dst 1939 && intnetp->intnet_mask == rt->rt_mask) { 1940 state |= (RS_NET_SYN | RS_NET_INT); 1941 break; 1942 } 1943 } 1944 } 1945 1946 if (ifp1 != NULL || (state & RS_NET_SYN)) { 1947 struct rt_spare new = rt->rt_spares[0]; 1948 new.rts_ifp = ifp1; 1949 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state), 1950 &new, 0); 1951 } else { 1952 rtbad(rt); 1953 } 1954 } 1955 1956 1957 /* Called while walking the table looking for sick interfaces 1958 * or after a time change. 1959 */ 1960 /* ARGSUSED */ 1961 int 1962 walk_bad(struct radix_node *rn, 1963 struct walkarg *argp UNUSED) 1964 { 1965 #define RT ((struct rt_entry *)rn) 1966 struct rt_spare *rts; 1967 int i; 1968 1969 1970 /* fix any spare routes through the interface 1971 */ 1972 rts = RT->rt_spares; 1973 for (i = NUM_SPARES; i != 1; i--) { 1974 rts++; 1975 if (rts->rts_metric < HOPCNT_INFINITY 1976 && (rts->rts_ifp == 0 1977 || (rts->rts_ifp->int_state & IS_BROKE))) 1978 rts_delete(RT, rts); 1979 } 1980 1981 /* Deal with the main route 1982 */ 1983 /* finished if it has been handled before or if its interface is ok 1984 */ 1985 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE)) 1986 return 0; 1987 1988 /* Bad routes for other than interfaces are easy. 1989 */ 1990 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) { 1991 rtbad(RT); 1992 return 0; 1993 } 1994 1995 rtbad_sub(RT); 1996 return 0; 1997 #undef RT 1998 } 1999 2000 2001 /* Check the age of an individual route. 2002 */ 2003 /* ARGSUSED */ 2004 static int 2005 walk_age(struct radix_node *rn, 2006 struct walkarg *argp UNUSED) 2007 { 2008 #define RT ((struct rt_entry *)rn) 2009 struct interface *ifp; 2010 struct rt_spare *rts; 2011 int i; 2012 2013 2014 /* age all of the spare routes, including the primary route 2015 * currently in use 2016 */ 2017 rts = RT->rt_spares; 2018 for (i = NUM_SPARES; i != 0; i--, rts++) { 2019 2020 ifp = rts->rts_ifp; 2021 if (i == NUM_SPARES) { 2022 if (!AGE_RT(RT->rt_state, ifp)) { 2023 /* Keep various things from deciding ageless 2024 * routes are stale 2025 */ 2026 rts->rts_time = now.tv_sec; 2027 continue; 2028 } 2029 2030 /* forget RIP routes after RIP has been turned off. 2031 */ 2032 if (rip_sock < 0) { 2033 rtdelete(RT); 2034 return 0; 2035 } 2036 } 2037 2038 /* age failing routes 2039 */ 2040 if (age_bad_gate == rts->rts_gate 2041 && rts->rts_time >= now_stale) { 2042 rts->rts_time -= SUPPLY_INTERVAL; 2043 } 2044 2045 /* trash the spare routes when they go bad */ 2046 if (rts->rts_metric < HOPCNT_INFINITY 2047 && now_garbage > rts->rts_time 2048 && i != NUM_SPARES) 2049 rts_delete(RT, rts); 2050 } 2051 2052 2053 /* finished if the active route is still fresh */ 2054 if (now_stale <= RT->rt_time) 2055 return 0; 2056 2057 /* try to switch to an alternative */ 2058 rtswitch(RT, 0); 2059 2060 /* Delete a dead route after it has been publically mourned. */ 2061 if (now_garbage > RT->rt_time) { 2062 rtdelete(RT); 2063 return 0; 2064 } 2065 2066 /* Start poisoning a bad route before deleting it. */ 2067 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) { 2068 struct rt_spare new = RT->rt_spares[0]; 2069 new.rts_metric = HOPCNT_INFINITY; 2070 rtchange(RT, RT->rt_state, &new, 0); 2071 } 2072 return 0; 2073 } 2074 2075 2076 /* Watch for dead routes and interfaces. 2077 */ 2078 void 2079 age(naddr bad_gate) 2080 { 2081 struct interface *ifp; 2082 int need_query = 0; 2083 2084 /* If not listening to RIP, there is no need to age the routes in 2085 * the table. 2086 */ 2087 age_timer.tv_sec = (now.tv_sec 2088 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL)); 2089 2090 /* Check for dead IS_REMOTE interfaces by timing their 2091 * transmissions. 2092 */ 2093 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 2094 if (!(ifp->int_state & IS_REMOTE)) 2095 continue; 2096 2097 /* ignore unreachable remote interfaces */ 2098 if (!check_remote(ifp)) 2099 continue; 2100 2101 /* Restore remote interface that has become reachable 2102 */ 2103 if (ifp->int_state & IS_BROKE) 2104 if_ok(ifp, "remote "); 2105 2106 if (ifp->int_act_time != NEVER 2107 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) { 2108 msglog("remote interface %s to %s timed out after" 2109 " %ld:%ld", 2110 ifp->int_name, 2111 naddr_ntoa(ifp->int_dstaddr), 2112 (now.tv_sec - ifp->int_act_time)/60, 2113 (now.tv_sec - ifp->int_act_time)%60); 2114 if_sick(ifp); 2115 } 2116 2117 /* If we have not heard from the other router 2118 * recently, ask it. 2119 */ 2120 if (now.tv_sec >= ifp->int_query_time) { 2121 ifp->int_query_time = NEVER; 2122 need_query = 1; 2123 } 2124 } 2125 2126 /* Age routes. */ 2127 age_bad_gate = bad_gate; 2128 rn_walktree(rhead, walk_age, 0); 2129 2130 /* delete old redirected routes to keep the kernel table small 2131 * and prevent blackholes 2132 */ 2133 del_redirects(bad_gate, now.tv_sec-STALE_TIME); 2134 2135 /* Update the kernel routing table. */ 2136 fix_kern(); 2137 2138 /* poke reticent remote gateways */ 2139 if (need_query) 2140 rip_query(); 2141 } 2142