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 * $DragonFly: src/sbin/routed/table.c,v 1.6 2005/03/16 21:21:34 cpressey Exp $ 35 */ 36 37 #include "defs.h" 38 39 #if !defined(sgi) && !defined(__NetBSD__) 40 static char sccsid[] __attribute__((unused)) = "@(#)tables.c 8.1 (Berkeley) 6/5/93"; 41 #elif defined(__NetBSD__) 42 __RCSID("$NetBSD$"); 43 #endif 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, 0 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 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 seqnum, 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 dst = 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 = seqnum; 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 > seqnum) 418 ag->ag_seqno = seqnum; 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 (seqnum > ag->ag_seqno) 460 seqnum = 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 (seqnum >= ag->ag_seqno) 522 seqnum = ag->ag_seqno; 523 else 524 ag->ag_seqno = seqnum; 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 (seqnum > ag->ag_seqno) 541 seqnum = ag->ag_seqno; 542 else 543 ag->ag_seqno = seqnum; 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 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 = seqnum; 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 #define NEW_RTM_PAT "RTM type %#x" 643 static char name0[sizeof(NEW_RTM_PAT)+2]; 644 645 646 if (type > sizeof(rtm_types)/sizeof(rtm_types[0]) 647 || type == 0) { 648 snprintf(name0, sizeof(name0), NEW_RTM_PAT, type); 649 return name0; 650 } else { 651 return rtm_types[type-1]; 652 } 653 #undef NEW_RTM_PAT 654 } 655 656 657 /* Trim a mask in a sockaddr 658 * Produce a length of 0 for an address of 0. 659 * Otherwise produce the index of the first zero byte. 660 */ 661 void 662 #ifdef _HAVE_SIN_LEN 663 masktrim(struct sockaddr_in *ap) 664 #else 665 masktrim(struct sockaddr_in_new *ap) 666 #endif 667 { 668 char *cp; 669 670 if (ap->sin_addr.s_addr == 0) { 671 ap->sin_len = 0; 672 return; 673 } 674 cp = (char *)(&ap->sin_addr.s_addr+1); 675 while (*--cp == 0) 676 continue; 677 ap->sin_len = cp - (char*)ap + 1; 678 } 679 680 681 /* Tell the kernel to add, delete or change a route 682 */ 683 static void 684 rtioctl(int action, /* RTM_DELETE, etc */ 685 naddr dst, 686 naddr gate, 687 naddr mask, 688 int metric, 689 int flags) 690 { 691 struct { 692 struct rt_msghdr w_rtm; 693 struct sockaddr_in w_dst; 694 struct sockaddr_in w_gate; 695 #ifdef _HAVE_SA_LEN 696 struct sockaddr_in w_mask; 697 #else 698 struct sockaddr_in_new w_mask; 699 #endif 700 } w; 701 long cc; 702 # define PAT " %-10s %s metric=%d flags=%#x" 703 # define ARGS rtm_type_name(action), rtname(dst,mask,gate), metric, flags 704 705 again: 706 memset(&w, 0, sizeof(w)); 707 w.w_rtm.rtm_msglen = sizeof(w); 708 w.w_rtm.rtm_version = RTM_VERSION; 709 w.w_rtm.rtm_type = action; 710 w.w_rtm.rtm_flags = flags; 711 w.w_rtm.rtm_seq = ++rt_sock_seqno; 712 w.w_rtm.rtm_addrs = RTA_DST|RTA_GATEWAY; 713 if (metric != 0 || action == RTM_CHANGE) { 714 w.w_rtm.rtm_rmx.rmx_hopcount = metric; 715 w.w_rtm.rtm_inits |= RTV_HOPCOUNT; 716 } 717 w.w_dst.sin_family = AF_INET; 718 w.w_dst.sin_addr.s_addr = dst; 719 w.w_gate.sin_family = AF_INET; 720 w.w_gate.sin_addr.s_addr = gate; 721 #ifdef _HAVE_SA_LEN 722 w.w_dst.sin_len = sizeof(w.w_dst); 723 w.w_gate.sin_len = sizeof(w.w_gate); 724 #endif 725 if (mask == HOST_MASK) { 726 w.w_rtm.rtm_flags |= RTF_HOST; 727 w.w_rtm.rtm_msglen -= sizeof(w.w_mask); 728 } else { 729 w.w_rtm.rtm_addrs |= RTA_NETMASK; 730 w.w_mask.sin_addr.s_addr = htonl(mask); 731 #ifdef _HAVE_SA_LEN 732 masktrim(&w.w_mask); 733 if (w.w_mask.sin_len == 0) 734 w.w_mask.sin_len = sizeof(long); 735 w.w_rtm.rtm_msglen -= (sizeof(w.w_mask) - w.w_mask.sin_len); 736 #endif 737 } 738 739 #ifndef NO_INSTALL 740 cc = write(rt_sock, &w, w.w_rtm.rtm_msglen); 741 if (cc < 0) { 742 if (errno == ESRCH 743 && (action == RTM_CHANGE || action == RTM_DELETE)) { 744 trace_act("route disappeared before" PAT, ARGS); 745 if (action == RTM_CHANGE) { 746 action = RTM_ADD; 747 goto again; 748 } 749 return; 750 } 751 msglog("write(rt_sock)" PAT ": %s", ARGS, strerror(errno)); 752 return; 753 } else if (cc != w.w_rtm.rtm_msglen) { 754 msglog("write(rt_sock) wrote %ld instead of %d for" PAT, 755 cc, w.w_rtm.rtm_msglen, ARGS); 756 return; 757 } 758 #endif 759 if (TRACEKERNEL) 760 trace_misc("write kernel" PAT, ARGS); 761 #undef PAT 762 #undef ARGS 763 } 764 765 766 #define KHASH_SIZE 71 /* should be prime */ 767 #define KHASH(a,m) khash_bins[((a) ^ (m)) % KHASH_SIZE] 768 static struct khash { 769 struct khash *k_next; 770 naddr k_dst; 771 naddr k_mask; 772 naddr k_gate; 773 short k_metric; 774 u_short k_state; 775 #define KS_NEW 0x001 776 #define KS_DELETE 0x002 /* need to delete the route */ 777 #define KS_ADD 0x004 /* add to the kernel */ 778 #define KS_CHANGE 0x008 /* tell kernel to change the route */ 779 #define KS_DEL_ADD 0x010 /* delete & add to change the kernel */ 780 #define KS_STATIC 0x020 /* Static flag in kernel */ 781 #define KS_GATEWAY 0x040 /* G flag in kernel */ 782 #define KS_DYNAMIC 0x080 /* result of redirect */ 783 #define KS_DELETED 0x100 /* already deleted from kernel */ 784 #define KS_CHECK 0x200 785 time_t k_keep; 786 #define K_KEEP_LIM 30 787 time_t k_redirect_time; /* when redirected route 1st seen */ 788 } *khash_bins[KHASH_SIZE]; 789 790 791 static struct khash* 792 kern_find(naddr dst, naddr mask, struct khash ***ppk) 793 { 794 struct khash *k, **pk; 795 796 for (pk = &KHASH(dst,mask); (k = *pk) != 0; pk = &k->k_next) { 797 if (k->k_dst == dst && k->k_mask == mask) 798 break; 799 } 800 if (ppk != 0) 801 *ppk = pk; 802 return k; 803 } 804 805 806 static struct khash* 807 kern_add(naddr dst, naddr mask) 808 { 809 struct khash *k, **pk; 810 811 k = kern_find(dst, mask, &pk); 812 if (k != 0) 813 return k; 814 815 k = (struct khash *)rtmalloc(sizeof(*k), "kern_add"); 816 817 memset(k, 0, sizeof(*k)); 818 k->k_dst = dst; 819 k->k_mask = mask; 820 k->k_state = KS_NEW; 821 k->k_keep = now.tv_sec; 822 *pk = k; 823 824 return k; 825 } 826 827 828 /* If a kernel route has a non-zero metric, check that it is still in the 829 * daemon table, and not deleted by interfaces coming and going. 830 */ 831 static void 832 kern_check_static(struct khash *k, 833 struct interface *ifp) 834 { 835 struct rt_entry *rt; 836 struct rt_spare new; 837 838 if (k->k_metric == 0) 839 return; 840 841 memset(&new, 0, sizeof(new)); 842 new.rts_ifp = ifp; 843 new.rts_gate = k->k_gate; 844 new.rts_router = (ifp != 0) ? ifp->int_addr : loopaddr; 845 new.rts_metric = k->k_metric; 846 new.rts_time = now.tv_sec; 847 848 rt = rtget(k->k_dst, k->k_mask); 849 if (rt != 0) { 850 if (!(rt->rt_state & RS_STATIC)) 851 rtchange(rt, rt->rt_state | RS_STATIC, &new, 0); 852 } else { 853 rtadd(k->k_dst, k->k_mask, RS_STATIC, &new); 854 } 855 } 856 857 858 /* operate on a kernel entry 859 */ 860 static void 861 kern_ioctl(struct khash *k, 862 int action, /* RTM_DELETE, etc */ 863 int flags) 864 865 { 866 switch (action) { 867 case RTM_DELETE: 868 k->k_state &= ~KS_DYNAMIC; 869 if (k->k_state & KS_DELETED) 870 return; 871 k->k_state |= KS_DELETED; 872 break; 873 case RTM_ADD: 874 k->k_state &= ~KS_DELETED; 875 break; 876 case RTM_CHANGE: 877 if (k->k_state & KS_DELETED) { 878 action = RTM_ADD; 879 k->k_state &= ~KS_DELETED; 880 } 881 break; 882 } 883 884 rtioctl(action, k->k_dst, k->k_gate, k->k_mask, k->k_metric, flags); 885 } 886 887 888 /* add a route the kernel told us 889 */ 890 static void 891 rtm_add(struct rt_msghdr *rtm, 892 struct rt_addrinfo *info, 893 time_t keep) 894 { 895 struct khash *k; 896 struct interface *ifp; 897 naddr mask; 898 899 900 if (rtm->rtm_flags & RTF_HOST) { 901 mask = HOST_MASK; 902 } else if (INFO_MASK(info) != 0) { 903 mask = ntohl(S_ADDR(INFO_MASK(info))); 904 } else { 905 msglog("ignore %s without mask", rtm_type_name(rtm->rtm_type)); 906 return; 907 } 908 909 k = kern_add(S_ADDR(INFO_DST(info)), mask); 910 if (k->k_state & KS_NEW) 911 k->k_keep = now.tv_sec+keep; 912 if (INFO_GATE(info) == 0) { 913 trace_act("note %s without gateway", 914 rtm_type_name(rtm->rtm_type)); 915 k->k_metric = HOPCNT_INFINITY; 916 } else if (INFO_GATE(info)->sa_family != AF_INET) { 917 trace_act("note %s with gateway AF=%d", 918 rtm_type_name(rtm->rtm_type), 919 INFO_GATE(info)->sa_family); 920 k->k_metric = HOPCNT_INFINITY; 921 } else { 922 k->k_gate = S_ADDR(INFO_GATE(info)); 923 k->k_metric = rtm->rtm_rmx.rmx_hopcount; 924 if (k->k_metric < 0) 925 k->k_metric = 0; 926 else if (k->k_metric > HOPCNT_INFINITY-1) 927 k->k_metric = HOPCNT_INFINITY-1; 928 } 929 k->k_state &= ~(KS_DELETE | KS_ADD | KS_CHANGE | KS_DEL_ADD 930 | KS_DELETED | KS_GATEWAY | KS_STATIC 931 | KS_NEW | KS_CHECK); 932 if (rtm->rtm_flags & RTF_GATEWAY) 933 k->k_state |= KS_GATEWAY; 934 if (rtm->rtm_flags & RTF_STATIC) 935 k->k_state |= KS_STATIC; 936 937 if (0 != (rtm->rtm_flags & (RTF_DYNAMIC | RTF_MODIFIED))) { 938 if (INFO_AUTHOR(info) != 0 939 && INFO_AUTHOR(info)->sa_family == AF_INET) 940 ifp = iflookup(S_ADDR(INFO_AUTHOR(info))); 941 else 942 ifp = 0; 943 if (supplier 944 && (ifp == 0 || !(ifp->int_state & IS_REDIRECT_OK))) { 945 /* Routers are not supposed to listen to redirects, 946 * so delete it if it came via an unknown interface 947 * or the interface does not have special permission. 948 */ 949 k->k_state &= ~KS_DYNAMIC; 950 k->k_state |= KS_DELETE; 951 LIM_SEC(need_kern, 0); 952 trace_act("mark for deletion redirected %s --> %s" 953 " via %s", 954 addrname(k->k_dst, k->k_mask, 0), 955 naddr_ntoa(k->k_gate), 956 ifp ? ifp->int_name : "unknown interface"); 957 } else { 958 k->k_state |= KS_DYNAMIC; 959 k->k_redirect_time = now.tv_sec; 960 trace_act("accept redirected %s --> %s via %s", 961 addrname(k->k_dst, k->k_mask, 0), 962 naddr_ntoa(k->k_gate), 963 ifp ? ifp->int_name : "unknown interface"); 964 } 965 return; 966 } 967 968 /* If it is not a static route, quit until the next comparison 969 * between the kernel and daemon tables, when it will be deleted. 970 */ 971 if (!(k->k_state & KS_STATIC)) { 972 k->k_state |= KS_DELETE; 973 LIM_SEC(need_kern, k->k_keep); 974 return; 975 } 976 977 /* Put static routes with real metrics into the daemon table so 978 * they can be advertised. 979 * 980 * Find the interface toward the gateway. 981 */ 982 ifp = iflookup(k->k_gate); 983 if (ifp == 0) 984 msglog("static route %s --> %s impossibly lacks ifp", 985 addrname(S_ADDR(INFO_DST(info)), mask, 0), 986 naddr_ntoa(k->k_gate)); 987 988 kern_check_static(k, ifp); 989 } 990 991 992 /* deal with packet loss 993 */ 994 static void 995 rtm_lose(struct rt_msghdr *rtm, 996 struct rt_addrinfo *info) 997 { 998 if (INFO_GATE(info) == 0 999 || INFO_GATE(info)->sa_family != AF_INET) { 1000 trace_act("ignore %s without gateway", 1001 rtm_type_name(rtm->rtm_type)); 1002 return; 1003 } 1004 1005 if (rdisc_ok) 1006 rdisc_age(S_ADDR(INFO_GATE(info))); 1007 age(S_ADDR(INFO_GATE(info))); 1008 } 1009 1010 1011 /* Make the gateway slot of an info structure point to something 1012 * useful. If it is not already useful, but it specifies an interface, 1013 * then fill in the sockaddr_in provided and point it there. 1014 */ 1015 static int 1016 get_info_gate(struct sockaddr **sap, 1017 struct sockaddr_in *in) 1018 { 1019 struct sockaddr_dl *sdl = (struct sockaddr_dl *)*sap; 1020 struct interface *ifp; 1021 1022 if (sdl == 0) 1023 return 0; 1024 if ((sdl)->sdl_family == AF_INET) 1025 return 1; 1026 if ((sdl)->sdl_family != AF_LINK) 1027 return 0; 1028 1029 ifp = ifwithindex(sdl->sdl_index, 1); 1030 if (ifp == 0) 1031 return 0; 1032 1033 in->sin_addr.s_addr = ifp->int_addr; 1034 #ifdef _HAVE_SA_LEN 1035 in->sin_len = sizeof(*in); 1036 #endif 1037 in->sin_family = AF_INET; 1038 *sap = (struct sockaddr *)in; 1039 1040 return 1; 1041 } 1042 1043 1044 /* Clean the kernel table by copying it to the daemon image. 1045 * Eventually the daemon will delete any extra routes. 1046 */ 1047 void 1048 flush_kern(void) 1049 { 1050 static char *sysctl_buf; 1051 static size_t sysctl_buf_size = 0; 1052 size_t needed; 1053 int mib[6]; 1054 char *next, *lim; 1055 struct rt_msghdr *rtm; 1056 struct sockaddr_in gate_sin; 1057 struct rt_addrinfo info; 1058 int i; 1059 struct khash *k; 1060 1061 1062 for (i = 0; i < KHASH_SIZE; i++) { 1063 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1064 k->k_state |= KS_CHECK; 1065 } 1066 } 1067 1068 mib[0] = CTL_NET; 1069 mib[1] = PF_ROUTE; 1070 mib[2] = 0; /* protocol */ 1071 mib[3] = 0; /* wildcard address family */ 1072 mib[4] = NET_RT_DUMP; 1073 mib[5] = 0; /* no flags */ 1074 for (;;) { 1075 if ((needed = sysctl_buf_size) != 0) { 1076 if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0) 1077 break; 1078 if (errno != ENOMEM && errno != EFAULT) 1079 BADERR(1,"flush_kern: sysctl(RT_DUMP)"); 1080 free(sysctl_buf); 1081 needed = 0; 1082 } 1083 if (sysctl(mib, 6, 0, &needed, 0, 0) < 0) 1084 BADERR(1,"flush_kern: sysctl(RT_DUMP) estimate"); 1085 /* Kludge around the habit of some systems, such as 1086 * BSD/OS 3.1, to not admit how many routes are in the 1087 * kernel, or at least to be quite wrong. 1088 */ 1089 needed += 50*(sizeof(*rtm)+5*sizeof(struct sockaddr)); 1090 sysctl_buf = rtmalloc(sysctl_buf_size = needed, 1091 "flush_kern sysctl(RT_DUMP)"); 1092 } 1093 1094 lim = sysctl_buf + needed; 1095 for (next = sysctl_buf; next < lim; next += rtm->rtm_msglen) { 1096 rtm = (struct rt_msghdr *)next; 1097 if (rtm->rtm_msglen == 0) { 1098 msglog("zero length kernel route at " 1099 " %#lx in buffer %#lx before %#lx", 1100 (u_long)rtm, (u_long)sysctl_buf, (u_long)lim); 1101 break; 1102 } 1103 1104 rt_xaddrs(&info, 1105 (struct sockaddr *)(rtm+1), 1106 (struct sockaddr *)(next + rtm->rtm_msglen), 1107 rtm->rtm_addrs); 1108 1109 if (INFO_DST(&info) == 0 1110 || INFO_DST(&info)->sa_family != AF_INET) 1111 continue; 1112 1113 /* ignore ARP table entries on systems with a merged route 1114 * and ARP table. 1115 */ 1116 if (rtm->rtm_flags & RTF_LLINFO) 1117 continue; 1118 1119 /* ignore multicast addresses 1120 */ 1121 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) 1122 continue; 1123 1124 if (!get_info_gate(&INFO_GATE(&info), &gate_sin)) 1125 continue; 1126 1127 /* Note static routes and interface routes, and also 1128 * preload the image of the kernel table so that 1129 * we can later clean it, as well as avoid making 1130 * unneeded changes. Keep the old kernel routes for a 1131 * few seconds to allow a RIP or router-discovery 1132 * response to be heard. 1133 */ 1134 rtm_add(rtm,&info,MIN_WAITTIME); 1135 } 1136 1137 for (i = 0; i < KHASH_SIZE; i++) { 1138 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1139 if (k->k_state & KS_CHECK) { 1140 msglog("%s --> %s disappeared from kernel", 1141 addrname(k->k_dst, k->k_mask, 0), 1142 naddr_ntoa(k->k_gate)); 1143 del_static(k->k_dst, k->k_mask, k->k_gate, 1); 1144 } 1145 } 1146 } 1147 } 1148 1149 1150 /* Listen to announcements from the kernel 1151 */ 1152 void 1153 read_rt(void) 1154 { 1155 long cc; 1156 struct interface *ifp; 1157 struct sockaddr_in gate_sin; 1158 naddr mask, gate; 1159 union { 1160 struct { 1161 struct rt_msghdr rtm; 1162 struct sockaddr addrs[RTAX_MAX]; 1163 } r; 1164 struct if_msghdr ifm; 1165 } m; 1166 char str[100], *strp; 1167 struct rt_addrinfo info; 1168 1169 1170 for (;;) { 1171 cc = read(rt_sock, &m, sizeof(m)); 1172 if (cc <= 0) { 1173 if (cc < 0 && errno != EWOULDBLOCK) 1174 LOGERR("read(rt_sock)"); 1175 return; 1176 } 1177 1178 if (m.r.rtm.rtm_version != RTM_VERSION) { 1179 msglog("bogus routing message version %d", 1180 m.r.rtm.rtm_version); 1181 continue; 1182 } 1183 1184 /* Ignore our own results. 1185 */ 1186 if (m.r.rtm.rtm_type <= RTM_CHANGE 1187 && m.r.rtm.rtm_pid == mypid) { 1188 static int complained = 0; 1189 if (!complained) { 1190 msglog("receiving our own change messages"); 1191 complained = 1; 1192 } 1193 continue; 1194 } 1195 1196 if (m.r.rtm.rtm_type == RTM_IFINFO 1197 || m.r.rtm.rtm_type == RTM_NEWADDR 1198 || m.r.rtm.rtm_type == RTM_DELADDR) { 1199 ifp = ifwithindex(m.ifm.ifm_index, 1200 m.r.rtm.rtm_type != RTM_DELADDR); 1201 if (ifp == 0) 1202 trace_act("note %s with flags %#x" 1203 " for unknown interface index #%d", 1204 rtm_type_name(m.r.rtm.rtm_type), 1205 m.ifm.ifm_flags, 1206 m.ifm.ifm_index); 1207 else 1208 trace_act("note %s with flags %#x for %s", 1209 rtm_type_name(m.r.rtm.rtm_type), 1210 m.ifm.ifm_flags, 1211 ifp->int_name); 1212 1213 /* After being informed of a change to an interface, 1214 * check them all now if the check would otherwise 1215 * be a long time from now, if the interface is 1216 * not known, or if the interface has been turned 1217 * off or on. 1218 */ 1219 if (ifinit_timer.tv_sec-now.tv_sec>=CHECK_BAD_INTERVAL 1220 || ifp == 0 1221 || ((ifp->int_if_flags ^ m.ifm.ifm_flags) 1222 & IFF_UP) != 0) 1223 ifinit_timer.tv_sec = now.tv_sec; 1224 continue; 1225 } 1226 1227 strcpy(str, rtm_type_name(m.r.rtm.rtm_type)); 1228 strp = &str[strlen(str)]; 1229 if (m.r.rtm.rtm_type <= RTM_CHANGE) 1230 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid); 1231 1232 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX], 1233 m.r.rtm.rtm_addrs); 1234 1235 if (INFO_DST(&info) == 0) { 1236 trace_act("ignore %s without dst", str); 1237 continue; 1238 } 1239 1240 if (INFO_DST(&info)->sa_family != AF_INET) { 1241 trace_act("ignore %s for AF %d", str, 1242 INFO_DST(&info)->sa_family); 1243 continue; 1244 } 1245 1246 mask = ((INFO_MASK(&info) != 0) 1247 ? ntohl(S_ADDR(INFO_MASK(&info))) 1248 : (m.r.rtm.rtm_flags & RTF_HOST) 1249 ? HOST_MASK 1250 : std_mask(S_ADDR(INFO_DST(&info)))); 1251 1252 strp += sprintf(strp, ": %s", 1253 addrname(S_ADDR(INFO_DST(&info)), mask, 0)); 1254 1255 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) { 1256 trace_act("ignore multicast %s", str); 1257 continue; 1258 } 1259 1260 if (m.r.rtm.rtm_flags & RTF_LLINFO) { 1261 trace_act("ignore ARP %s", str); 1262 continue; 1263 } 1264 1265 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) { 1266 gate = S_ADDR(INFO_GATE(&info)); 1267 strp += sprintf(strp, " --> %s", naddr_ntoa(gate)); 1268 } else { 1269 gate = 0; 1270 } 1271 1272 if (INFO_AUTHOR(&info) != 0) 1273 strp += sprintf(strp, " by authority of %s", 1274 saddr_ntoa(INFO_AUTHOR(&info))); 1275 1276 switch (m.r.rtm.rtm_type) { 1277 case RTM_ADD: 1278 case RTM_CHANGE: 1279 case RTM_REDIRECT: 1280 if (m.r.rtm.rtm_errno != 0) { 1281 trace_act("ignore %s with \"%s\" error", 1282 str, strerror(m.r.rtm.rtm_errno)); 1283 } else { 1284 trace_act("%s", str); 1285 rtm_add(&m.r.rtm,&info,0); 1286 } 1287 break; 1288 1289 case RTM_DELETE: 1290 if (m.r.rtm.rtm_errno != 0 1291 && m.r.rtm.rtm_errno != ESRCH) { 1292 trace_act("ignore %s with \"%s\" error", 1293 str, strerror(m.r.rtm.rtm_errno)); 1294 } else { 1295 trace_act("%s", str); 1296 del_static(S_ADDR(INFO_DST(&info)), mask, 1297 gate, 1); 1298 } 1299 break; 1300 1301 case RTM_LOSING: 1302 trace_act("%s", str); 1303 rtm_lose(&m.r.rtm,&info); 1304 break; 1305 1306 default: 1307 trace_act("ignore %s", str); 1308 break; 1309 } 1310 } 1311 } 1312 1313 1314 /* after aggregating, note routes that belong in the kernel 1315 */ 1316 static void 1317 kern_out(struct ag_info *ag) 1318 { 1319 struct khash *k; 1320 1321 1322 /* Do not install bad routes if they are not already present. 1323 * This includes routes that had RS_NET_SYN for interfaces that 1324 * recently died. 1325 */ 1326 if (ag->ag_metric == HOPCNT_INFINITY) { 1327 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0); 1328 if (k == 0) 1329 return; 1330 } else { 1331 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask); 1332 } 1333 1334 if (k->k_state & KS_NEW) { 1335 /* will need to add new entry to the kernel table */ 1336 k->k_state = KS_ADD; 1337 if (ag->ag_state & AGS_GATEWAY) 1338 k->k_state |= KS_GATEWAY; 1339 k->k_gate = ag->ag_gate; 1340 k->k_metric = ag->ag_metric; 1341 return; 1342 } 1343 1344 if (k->k_state & KS_STATIC) 1345 return; 1346 1347 /* modify existing kernel entry if necessary */ 1348 if (k->k_gate != ag->ag_gate 1349 || k->k_metric != ag->ag_metric) { 1350 /* Must delete bad interface routes etc. to change them. */ 1351 if (k->k_metric == HOPCNT_INFINITY) 1352 k->k_state |= KS_DEL_ADD; 1353 k->k_gate = ag->ag_gate; 1354 k->k_metric = ag->ag_metric; 1355 k->k_state |= KS_CHANGE; 1356 } 1357 1358 /* If the daemon thinks the route should exist, forget 1359 * about any redirections. 1360 * If the daemon thinks the route should exist, eventually 1361 * override manual intervention by the operator. 1362 */ 1363 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) { 1364 k->k_state &= ~KS_DYNAMIC; 1365 k->k_state |= (KS_ADD | KS_DEL_ADD); 1366 } 1367 1368 if ((k->k_state & KS_GATEWAY) 1369 && !(ag->ag_state & AGS_GATEWAY)) { 1370 k->k_state &= ~KS_GATEWAY; 1371 k->k_state |= (KS_ADD | KS_DEL_ADD); 1372 } else if (!(k->k_state & KS_GATEWAY) 1373 && (ag->ag_state & AGS_GATEWAY)) { 1374 k->k_state |= KS_GATEWAY; 1375 k->k_state |= (KS_ADD | KS_DEL_ADD); 1376 } 1377 1378 /* Deleting-and-adding is necessary to change aspects of a route. 1379 * Just delete instead of deleting and then adding a bad route. 1380 * Otherwise, we want to keep the route in the kernel. 1381 */ 1382 if (k->k_metric == HOPCNT_INFINITY 1383 && (k->k_state & KS_DEL_ADD)) 1384 k->k_state |= KS_DELETE; 1385 else 1386 k->k_state &= ~KS_DELETE; 1387 #undef RT 1388 } 1389 1390 1391 /* ARGSUSED */ 1392 static int 1393 walk_kern(struct radix_node *rn, 1394 struct walkarg *argp UNUSED) 1395 { 1396 #define RT ((struct rt_entry *)rn) 1397 char metric, pref; 1398 u_int ags = 0; 1399 1400 1401 /* Do not install synthetic routes */ 1402 if (RT->rt_state & RS_NET_SYN) 1403 return 0; 1404 1405 if (!(RT->rt_state & RS_IF)) { 1406 /* This is an ordinary route, not for an interface. 1407 */ 1408 1409 /* aggregate, ordinary good routes without regard to 1410 * their metric 1411 */ 1412 pref = 1; 1413 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1414 1415 /* Do not install host routes directly to hosts, to avoid 1416 * interfering with ARP entries in the kernel table. 1417 */ 1418 if (RT_ISHOST(RT) 1419 && ntohl(RT->rt_dst) == RT->rt_gate) 1420 return 0; 1421 1422 } else { 1423 /* This is an interface route. 1424 * Do not install routes for "external" remote interfaces. 1425 */ 1426 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL)) 1427 return 0; 1428 1429 /* Interfaces should override received routes. 1430 */ 1431 pref = 0; 1432 ags |= (AGS_IF | AGS_CORS_GATE); 1433 1434 /* If it is not an interface, or an alias for an interface, 1435 * it must be a "gateway." 1436 * 1437 * If it is a "remote" interface, it is also a "gateway" to 1438 * the kernel if is not a alias. 1439 */ 1440 if (RT->rt_ifp == 0 1441 || (RT->rt_ifp->int_state & IS_REMOTE)) 1442 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1443 } 1444 1445 /* If RIP is off and IRDP is on, let the route to the discovered 1446 * route suppress any RIP routes. Eventually the RIP routes 1447 * will time-out and be deleted. This reaches the steady-state 1448 * quicker. 1449 */ 1450 if ((RT->rt_state & RS_RDISC) && rip_sock < 0) 1451 ags |= AGS_CORS_GATE; 1452 1453 metric = RT->rt_metric; 1454 if (metric == HOPCNT_INFINITY) { 1455 /* if the route is dead, so try hard to aggregate. */ 1456 pref = HOPCNT_INFINITY; 1457 ags |= (AGS_FINE_GATE | AGS_SUPPRESS); 1458 ags &= ~(AGS_IF | AGS_CORS_GATE); 1459 } 1460 1461 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0, 1462 metric,pref, 0, 0, ags, kern_out); 1463 return 0; 1464 #undef RT 1465 } 1466 1467 1468 /* Update the kernel table to match the daemon table. 1469 */ 1470 static void 1471 fix_kern(void) 1472 { 1473 int i; 1474 struct khash *k, **pk; 1475 1476 1477 need_kern = age_timer; 1478 1479 /* Walk daemon table, updating the copy of the kernel table. 1480 */ 1481 rn_walktree(rhead, walk_kern, 0); 1482 ag_flush(0,0,kern_out); 1483 1484 for (i = 0; i < KHASH_SIZE; i++) { 1485 for (pk = &khash_bins[i]; (k = *pk) != 0; ) { 1486 /* Do not touch static routes */ 1487 if (k->k_state & KS_STATIC) { 1488 kern_check_static(k,0); 1489 pk = &k->k_next; 1490 continue; 1491 } 1492 1493 /* check hold on routes deleted by the operator */ 1494 if (k->k_keep > now.tv_sec) { 1495 /* ensure we check when the hold is over */ 1496 LIM_SEC(need_kern, k->k_keep); 1497 /* mark for the next cycle */ 1498 k->k_state |= KS_DELETE; 1499 pk = &k->k_next; 1500 continue; 1501 } 1502 1503 if ((k->k_state & KS_DELETE) 1504 && !(k->k_state & KS_DYNAMIC)) { 1505 kern_ioctl(k, RTM_DELETE, 0); 1506 *pk = k->k_next; 1507 free(k); 1508 continue; 1509 } 1510 1511 if (k->k_state & KS_DEL_ADD) 1512 kern_ioctl(k, RTM_DELETE, 0); 1513 1514 if (k->k_state & KS_ADD) { 1515 kern_ioctl(k, RTM_ADD, 1516 ((0 != (k->k_state & (KS_GATEWAY 1517 | KS_DYNAMIC))) 1518 ? RTF_GATEWAY : 0)); 1519 } else if (k->k_state & KS_CHANGE) { 1520 kern_ioctl(k, RTM_CHANGE, 1521 ((0 != (k->k_state & (KS_GATEWAY 1522 | KS_DYNAMIC))) 1523 ? RTF_GATEWAY : 0)); 1524 } 1525 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD); 1526 1527 /* Mark this route to be deleted in the next cycle. 1528 * This deletes routes that disappear from the 1529 * daemon table, since the normal aging code 1530 * will clear the bit for routes that have not 1531 * disappeared from the daemon table. 1532 */ 1533 k->k_state |= KS_DELETE; 1534 pk = &k->k_next; 1535 } 1536 } 1537 } 1538 1539 1540 /* Delete a static route in the image of the kernel table. 1541 */ 1542 void 1543 del_static(naddr dst, 1544 naddr mask, 1545 naddr gate, 1546 int gone) 1547 { 1548 struct khash *k; 1549 struct rt_entry *rt; 1550 1551 /* Just mark it in the table to be deleted next time the kernel 1552 * table is updated. 1553 * If it has already been deleted, mark it as such, and set its 1554 * keep-timer so that it will not be deleted again for a while. 1555 * This lets the operator delete a route added by the daemon 1556 * and add a replacement. 1557 */ 1558 k = kern_find(dst, mask, 0); 1559 if (k != 0 && (gate == 0 || k->k_gate == gate)) { 1560 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK); 1561 k->k_state |= KS_DELETE; 1562 if (gone) { 1563 k->k_state |= KS_DELETED; 1564 k->k_keep = now.tv_sec + K_KEEP_LIM; 1565 } 1566 } 1567 1568 rt = rtget(dst, mask); 1569 if (rt != 0 && (rt->rt_state & RS_STATIC)) 1570 rtbad(rt); 1571 } 1572 1573 1574 /* Delete all routes generated from ICMP Redirects that use a given gateway, 1575 * as well as old redirected routes. 1576 */ 1577 void 1578 del_redirects(naddr bad_gate, 1579 time_t old) 1580 { 1581 int i; 1582 struct khash *k; 1583 1584 1585 for (i = 0; i < KHASH_SIZE; i++) { 1586 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1587 if (!(k->k_state & KS_DYNAMIC) 1588 || (k->k_state & KS_STATIC)) 1589 continue; 1590 1591 if (k->k_gate != bad_gate 1592 && k->k_redirect_time > old 1593 && !supplier) 1594 continue; 1595 1596 k->k_state |= KS_DELETE; 1597 k->k_state &= ~KS_DYNAMIC; 1598 need_kern.tv_sec = now.tv_sec; 1599 trace_act("mark redirected %s --> %s for deletion", 1600 addrname(k->k_dst, k->k_mask, 0), 1601 naddr_ntoa(k->k_gate)); 1602 } 1603 } 1604 } 1605 1606 1607 /* Start the daemon tables. 1608 */ 1609 extern int max_keylen; 1610 1611 void 1612 rtinit(void) 1613 { 1614 int i; 1615 struct ag_info *ag; 1616 1617 /* Initialize the radix trees */ 1618 max_keylen = sizeof(struct sockaddr_in); 1619 rn_init(); 1620 rn_inithead(&rhead, 32); 1621 1622 /* mark all of the slots in the table free */ 1623 ag_avail = ag_slots; 1624 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) { 1625 ag->ag_fine = ag+1; 1626 ag++; 1627 } 1628 } 1629 1630 1631 #ifdef _HAVE_SIN_LEN 1632 static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET, 0, {0}, {0}}; 1633 static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET, 0, {0}, {0}}; 1634 #else 1635 static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET}; 1636 static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET}; 1637 #endif 1638 1639 1640 static void 1641 set_need_flash(void) 1642 { 1643 if (!need_flash) { 1644 need_flash = 1; 1645 /* Do not send the flash update immediately. Wait a little 1646 * while to hear from other routers. 1647 */ 1648 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME; 1649 } 1650 } 1651 1652 1653 /* Get a particular routing table entry 1654 */ 1655 struct rt_entry * 1656 rtget(naddr dst, naddr mask) 1657 { 1658 struct rt_entry *rt; 1659 1660 dst_sock.sin_addr.s_addr = dst; 1661 mask_sock.sin_addr.s_addr = htonl(mask); 1662 masktrim(&mask_sock); 1663 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead); 1664 if (!rt 1665 || rt->rt_dst != dst 1666 || rt->rt_mask != mask) 1667 return 0; 1668 1669 return rt; 1670 } 1671 1672 1673 /* Find a route to dst as the kernel would. 1674 */ 1675 struct rt_entry * 1676 rtfind(naddr dst) 1677 { 1678 dst_sock.sin_addr.s_addr = dst; 1679 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead); 1680 } 1681 1682 1683 /* add a route to the table 1684 */ 1685 void 1686 rtadd(naddr dst, 1687 naddr mask, 1688 u_int state, /* rt_state for the entry */ 1689 struct rt_spare *new) 1690 { 1691 struct rt_entry *rt; 1692 naddr smask; 1693 int i; 1694 struct rt_spare *rts; 1695 1696 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd"); 1697 memset(rt, 0, sizeof(*rt)); 1698 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) 1699 rts->rts_metric = HOPCNT_INFINITY; 1700 1701 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock; 1702 rt->rt_dst = dst; 1703 rt->rt_dst_sock.sin_family = AF_INET; 1704 #ifdef _HAVE_SIN_LEN 1705 rt->rt_dst_sock.sin_len = dst_sock.sin_len; 1706 #endif 1707 if (mask != HOST_MASK) { 1708 smask = std_mask(dst); 1709 if ((smask & ~mask) == 0 && mask > smask) 1710 state |= RS_SUBNET; 1711 } 1712 mask_sock.sin_addr.s_addr = htonl(mask); 1713 masktrim(&mask_sock); 1714 rt->rt_mask = mask; 1715 rt->rt_state = state; 1716 rt->rt_spares[0] = *new; 1717 rt->rt_time = now.tv_sec; 1718 rt->rt_poison_metric = HOPCNT_INFINITY; 1719 rt->rt_seqno = update_seqno; 1720 1721 if (++total_routes == MAX_ROUTES) 1722 msglog("have maximum (%d) routes", total_routes); 1723 if (TRACEACTIONS) 1724 trace_add_del("Add", rt); 1725 1726 need_kern.tv_sec = now.tv_sec; 1727 set_need_flash(); 1728 1729 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock, 1730 rhead, rt->rt_nodes)) { 1731 msglog("rnh_addaddr() failed for %s mask=%#lx", 1732 naddr_ntoa(dst), (u_long)mask); 1733 free(rt); 1734 } 1735 } 1736 1737 1738 /* notice a changed route 1739 */ 1740 void 1741 rtchange(struct rt_entry *rt, 1742 u_int state, /* new state bits */ 1743 struct rt_spare *new, 1744 char *label) 1745 { 1746 if (rt->rt_metric != new->rts_metric) { 1747 /* Fix the kernel immediately if it seems the route 1748 * has gone bad, since there may be a working route that 1749 * aggregates this route. 1750 */ 1751 if (new->rts_metric == HOPCNT_INFINITY) { 1752 need_kern.tv_sec = now.tv_sec; 1753 if (new->rts_time >= now.tv_sec - EXPIRE_TIME) 1754 new->rts_time = now.tv_sec - EXPIRE_TIME; 1755 } 1756 rt->rt_seqno = update_seqno; 1757 set_need_flash(); 1758 } 1759 1760 if (rt->rt_gate != new->rts_gate) { 1761 need_kern.tv_sec = now.tv_sec; 1762 rt->rt_seqno = update_seqno; 1763 set_need_flash(); 1764 } 1765 1766 state |= (rt->rt_state & RS_SUBNET); 1767 1768 /* Keep various things from deciding ageless routes are stale. 1769 */ 1770 if (!AGE_RT(state, new->rts_ifp)) 1771 new->rts_time = now.tv_sec; 1772 1773 if (TRACEACTIONS) 1774 trace_change(rt, state, new, 1775 label ? label : "Chg "); 1776 1777 rt->rt_state = state; 1778 rt->rt_spares[0] = *new; 1779 } 1780 1781 1782 /* check for a better route among the spares 1783 */ 1784 static struct rt_spare * 1785 rts_better(struct rt_entry *rt) 1786 { 1787 struct rt_spare *rts, *rts1; 1788 int i; 1789 1790 /* find the best alternative among the spares */ 1791 rts = rt->rt_spares+1; 1792 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) { 1793 if (BETTER_LINK(rt,rts1,rts)) 1794 rts = rts1; 1795 } 1796 1797 return rts; 1798 } 1799 1800 1801 /* switch to a backup route 1802 */ 1803 void 1804 rtswitch(struct rt_entry *rt, 1805 struct rt_spare *rts) 1806 { 1807 struct rt_spare swap; 1808 char label[10]; 1809 1810 1811 /* Do not change permanent routes */ 1812 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC 1813 | RS_NET_SYN | RS_IF))) 1814 return; 1815 1816 /* find the best alternative among the spares */ 1817 if (rts == 0) 1818 rts = rts_better(rt); 1819 1820 /* Do not bother if it is not worthwhile. 1821 */ 1822 if (!BETTER_LINK(rt, rts, rt->rt_spares)) 1823 return; 1824 1825 swap = rt->rt_spares[0]; 1826 sprintf(label, "Use #%d", (int)(rts - rt->rt_spares)); 1827 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label); 1828 if (swap.rts_metric == HOPCNT_INFINITY) { 1829 *rts = rts_empty; 1830 } else { 1831 *rts = swap; 1832 } 1833 } 1834 1835 1836 void 1837 rtdelete(struct rt_entry *rt) 1838 { 1839 struct khash *k; 1840 1841 1842 if (TRACEACTIONS) 1843 trace_add_del("Del", rt); 1844 1845 k = kern_find(rt->rt_dst, rt->rt_mask, 0); 1846 if (k != 0) { 1847 k->k_state |= KS_DELETE; 1848 need_kern.tv_sec = now.tv_sec; 1849 } 1850 1851 dst_sock.sin_addr.s_addr = rt->rt_dst; 1852 mask_sock.sin_addr.s_addr = htonl(rt->rt_mask); 1853 masktrim(&mask_sock); 1854 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock, 1855 rhead)) { 1856 msglog("rnh_deladdr() failed"); 1857 } else { 1858 free(rt); 1859 total_routes--; 1860 } 1861 } 1862 1863 1864 void 1865 rts_delete(struct rt_entry *rt, 1866 struct rt_spare *rts) 1867 { 1868 trace_upslot(rt, rts, &rts_empty); 1869 *rts = rts_empty; 1870 } 1871 1872 1873 /* Get rid of a bad route, and try to switch to a replacement. 1874 */ 1875 void 1876 rtbad(struct rt_entry *rt) 1877 { 1878 struct rt_spare new; 1879 1880 /* Poison the route */ 1881 new = rt->rt_spares[0]; 1882 new.rts_metric = HOPCNT_INFINITY; 1883 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0); 1884 rtswitch(rt, 0); 1885 } 1886 1887 1888 /* Junk a RS_NET_SYN or RS_LOCAL route, 1889 * unless it is needed by another interface. 1890 */ 1891 void 1892 rtbad_sub(struct rt_entry *rt) 1893 { 1894 struct interface *ifp, *ifp1; 1895 struct intnet *intnetp; 1896 u_int state; 1897 1898 1899 ifp1 = 0; 1900 state = 0; 1901 1902 if (rt->rt_state & RS_LOCAL) { 1903 /* Is this the route through loopback for the interface? 1904 * If so, see if it is used by any other interfaces, such 1905 * as a point-to-point interface with the same local address. 1906 */ 1907 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1908 /* Retain it if another interface needs it. 1909 */ 1910 if (ifp->int_addr == rt->rt_ifp->int_addr) { 1911 state |= RS_LOCAL; 1912 ifp1 = ifp; 1913 break; 1914 } 1915 } 1916 1917 } 1918 1919 if (!(state & RS_LOCAL)) { 1920 /* Retain RIPv1 logical network route if there is another 1921 * interface that justifies it. 1922 */ 1923 if (rt->rt_state & RS_NET_SYN) { 1924 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1925 if ((ifp->int_state & IS_NEED_NET_SYN) 1926 && rt->rt_mask == ifp->int_std_mask 1927 && rt->rt_dst == ifp->int_std_addr) { 1928 state |= RS_NET_SYN; 1929 ifp1 = ifp; 1930 break; 1931 } 1932 } 1933 } 1934 1935 /* or if there is an authority route that needs it. */ 1936 for (intnetp = intnets; 1937 intnetp != 0; 1938 intnetp = intnetp->intnet_next) { 1939 if (intnetp->intnet_addr == rt->rt_dst 1940 && intnetp->intnet_mask == rt->rt_mask) { 1941 state |= (RS_NET_SYN | RS_NET_INT); 1942 break; 1943 } 1944 } 1945 } 1946 1947 if (ifp1 != 0 || (state & RS_NET_SYN)) { 1948 struct rt_spare new = rt->rt_spares[0]; 1949 new.rts_ifp = ifp1; 1950 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state), 1951 &new, 0); 1952 } else { 1953 rtbad(rt); 1954 } 1955 } 1956 1957 1958 /* Called while walking the table looking for sick interfaces 1959 * or after a time change. 1960 */ 1961 /* ARGSUSED */ 1962 int 1963 walk_bad(struct radix_node *rn, 1964 struct walkarg *argp UNUSED) 1965 { 1966 #define RT ((struct rt_entry *)rn) 1967 struct rt_spare *rts; 1968 int i; 1969 1970 1971 /* fix any spare routes through the interface 1972 */ 1973 rts = RT->rt_spares; 1974 for (i = NUM_SPARES; i != 1; i--) { 1975 rts++; 1976 if (rts->rts_metric < HOPCNT_INFINITY 1977 && (rts->rts_ifp == 0 1978 || (rts->rts_ifp->int_state & IS_BROKE))) 1979 rts_delete(RT, rts); 1980 } 1981 1982 /* Deal with the main route 1983 */ 1984 /* finished if it has been handled before or if its interface is ok 1985 */ 1986 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE)) 1987 return 0; 1988 1989 /* Bad routes for other than interfaces are easy. 1990 */ 1991 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) { 1992 rtbad(RT); 1993 return 0; 1994 } 1995 1996 rtbad_sub(RT); 1997 return 0; 1998 #undef RT 1999 } 2000 2001 2002 /* Check the age of an individual route. 2003 */ 2004 /* ARGSUSED */ 2005 static int 2006 walk_age(struct radix_node *rn, 2007 struct walkarg *argp UNUSED) 2008 { 2009 #define RT ((struct rt_entry *)rn) 2010 struct interface *ifp; 2011 struct rt_spare *rts; 2012 int i; 2013 2014 2015 /* age all of the spare routes, including the primary route 2016 * currently in use 2017 */ 2018 rts = RT->rt_spares; 2019 for (i = NUM_SPARES; i != 0; i--, rts++) { 2020 2021 ifp = rts->rts_ifp; 2022 if (i == NUM_SPARES) { 2023 if (!AGE_RT(RT->rt_state, ifp)) { 2024 /* Keep various things from deciding ageless 2025 * routes are stale 2026 */ 2027 rts->rts_time = now.tv_sec; 2028 continue; 2029 } 2030 2031 /* forget RIP routes after RIP has been turned off. 2032 */ 2033 if (rip_sock < 0) { 2034 rtdelete(RT); 2035 return 0; 2036 } 2037 } 2038 2039 /* age failing routes 2040 */ 2041 if (age_bad_gate == rts->rts_gate 2042 && rts->rts_time >= now_stale) { 2043 rts->rts_time -= SUPPLY_INTERVAL; 2044 } 2045 2046 /* trash the spare routes when they go bad */ 2047 if (rts->rts_metric < HOPCNT_INFINITY 2048 && now_garbage > rts->rts_time 2049 && i != NUM_SPARES) 2050 rts_delete(RT, rts); 2051 } 2052 2053 2054 /* finished if the active route is still fresh */ 2055 if (now_stale <= RT->rt_time) 2056 return 0; 2057 2058 /* try to switch to an alternative */ 2059 rtswitch(RT, 0); 2060 2061 /* Delete a dead route after it has been publically mourned. */ 2062 if (now_garbage > RT->rt_time) { 2063 rtdelete(RT); 2064 return 0; 2065 } 2066 2067 /* Start poisoning a bad route before deleting it. */ 2068 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) { 2069 struct rt_spare new = RT->rt_spares[0]; 2070 new.rts_metric = HOPCNT_INFINITY; 2071 rtchange(RT, RT->rt_state, &new, 0); 2072 } 2073 return 0; 2074 } 2075 2076 2077 /* Watch for dead routes and interfaces. 2078 */ 2079 void 2080 age(naddr bad_gate) 2081 { 2082 struct interface *ifp; 2083 int need_query = 0; 2084 2085 /* If not listening to RIP, there is no need to age the routes in 2086 * the table. 2087 */ 2088 age_timer.tv_sec = (now.tv_sec 2089 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL)); 2090 2091 /* Check for dead IS_REMOTE interfaces by timing their 2092 * transmissions. 2093 */ 2094 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 2095 if (!(ifp->int_state & IS_REMOTE)) 2096 continue; 2097 2098 /* ignore unreachable remote interfaces */ 2099 if (!check_remote(ifp)) 2100 continue; 2101 2102 /* Restore remote interface that has become reachable 2103 */ 2104 if (ifp->int_state & IS_BROKE) 2105 if_ok(ifp, "remote "); 2106 2107 if (ifp->int_act_time != NEVER 2108 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) { 2109 msglog("remote interface %s to %s timed out after" 2110 " %ld:%ld", 2111 ifp->int_name, 2112 naddr_ntoa(ifp->int_dstaddr), 2113 (now.tv_sec - ifp->int_act_time)/60, 2114 (now.tv_sec - ifp->int_act_time)%60); 2115 if_sick(ifp); 2116 } 2117 2118 /* If we have not heard from the other router 2119 * recently, ask it. 2120 */ 2121 if (now.tv_sec >= ifp->int_query_time) { 2122 ifp->int_query_time = NEVER; 2123 need_query = 1; 2124 } 2125 } 2126 2127 /* Age routes. */ 2128 age_bad_gate = bad_gate; 2129 rn_walktree(rhead, walk_age, 0); 2130 2131 /* delete old redirected routes to keep the kernel table small 2132 * and prevent blackholes 2133 */ 2134 del_redirects(bad_gate, now.tv_sec-STALE_TIME); 2135 2136 /* Update the kernel routing table. */ 2137 fix_kern(); 2138 2139 /* poke reticent remote gateways */ 2140 if (need_query) 2141 rip_query(); 2142 } 2143