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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 #include "defs.h" 33 34 #ifdef __NetBSD__ 35 __RCSID("$NetBSD$"); 36 #elif defined(__FreeBSD__) 37 __RCSID("$FreeBSD$"); 38 #else 39 __RCSID("$Revision: 2.27 $"); 40 #ident "$Revision: 2.27 $" 41 #endif 42 43 static struct rt_spare *rts_better(struct rt_entry *); 44 static struct rt_spare rts_empty = {0,0,0,HOPCNT_INFINITY,0,0,0}; 45 static void set_need_flash(void); 46 #ifdef _HAVE_SIN_LEN 47 static void masktrim(struct sockaddr_in *ap); 48 #else 49 static void masktrim(struct sockaddr_in_new *ap); 50 #endif 51 52 53 struct radix_node_head *rhead; /* root of the radix tree */ 54 55 int need_flash = 1; /* flash update needed 56 * start =1 to suppress the 1st 57 */ 58 59 struct timeval age_timer; /* next check of old routes */ 60 struct timeval need_kern = { /* need to update kernel table */ 61 EPOCH+MIN_WAITTIME-1, 0 62 }; 63 64 int stopint; 65 66 int total_routes; 67 68 /* zap any old routes through this gateway */ 69 naddr age_bad_gate; 70 71 72 /* It is desirable to "aggregate" routes, to combine differing routes of 73 * the same metric and next hop into a common route with a smaller netmask 74 * or to suppress redundant routes, routes that add no information to 75 * routes with smaller netmasks. 76 * 77 * A route is redundant if and only if any and all routes with smaller 78 * but matching netmasks and nets are the same. Since routes are 79 * kept sorted in the radix tree, redundant routes always come second. 80 * 81 * There are two kinds of aggregations. First, two routes of the same bit 82 * mask and differing only in the least significant bit of the network 83 * number can be combined into a single route with a coarser mask. 84 * 85 * Second, a route can be suppressed in favor of another route with a more 86 * coarse mask provided no incompatible routes with intermediate masks 87 * are present. The second kind of aggregation involves suppressing routes. 88 * A route must not be suppressed if an incompatible route exists with 89 * an intermediate mask, since the suppressed route would be covered 90 * by the intermediate. 91 * 92 * This code relies on the radix tree walk encountering routes 93 * sorted first by address, with the smallest address first. 94 */ 95 96 struct ag_info ag_slots[NUM_AG_SLOTS], *ag_avail, *ag_corsest, *ag_finest; 97 98 /* #define DEBUG_AG */ 99 #ifdef DEBUG_AG 100 #define CHECK_AG() {int acnt = 0; struct ag_info *cag; \ 101 for (cag = ag_avail; cag != 0; cag = cag->ag_fine) \ 102 acnt++; \ 103 for (cag = ag_corsest; cag != 0; cag = cag->ag_fine) \ 104 acnt++; \ 105 if (acnt != NUM_AG_SLOTS) { \ 106 (void)fflush(stderr); \ 107 abort(); \ 108 } \ 109 } 110 #else 111 #define CHECK_AG() 112 #endif 113 114 115 /* Output the contents of an aggregation table slot. 116 * This function must always be immediately followed with the deletion 117 * of the target slot. 118 */ 119 static void 120 ag_out(struct ag_info *ag, 121 void (*out)(struct ag_info *)) 122 { 123 struct ag_info *ag_cors; 124 naddr bit; 125 126 127 /* Forget it if this route should not be output for split-horizon. */ 128 if (ag->ag_state & AGS_SPLIT_HZ) 129 return; 130 131 /* If we output both the even and odd twins, then the immediate parent, 132 * if it is present, is redundant, unless the parent manages to 133 * aggregate into something coarser. 134 * On successive calls, this code detects the even and odd twins, 135 * and marks the parent. 136 * 137 * Note that the order in which the radix tree code emits routes 138 * ensures that the twins are seen before the parent is emitted. 139 */ 140 ag_cors = ag->ag_cors; 141 if (ag_cors != 0 142 && ag_cors->ag_mask == ag->ag_mask<<1 143 && ag_cors->ag_dst_h == (ag->ag_dst_h & ag_cors->ag_mask)) { 144 ag_cors->ag_state |= ((ag_cors->ag_dst_h == ag->ag_dst_h) 145 ? AGS_REDUN0 146 : AGS_REDUN1); 147 } 148 149 /* Skip it if this route is itself redundant. 150 * 151 * It is ok to change the contents of the slot here, since it is 152 * always deleted next. 153 */ 154 if (ag->ag_state & AGS_REDUN0) { 155 if (ag->ag_state & AGS_REDUN1) 156 return; /* quit if fully redundant */ 157 /* make it finer if it is half-redundant */ 158 bit = (-ag->ag_mask) >> 1; 159 ag->ag_dst_h |= bit; 160 ag->ag_mask |= bit; 161 162 } else if (ag->ag_state & AGS_REDUN1) { 163 /* make it finer if it is half-redundant */ 164 bit = (-ag->ag_mask) >> 1; 165 ag->ag_mask |= bit; 166 } 167 out(ag); 168 } 169 170 171 static void 172 ag_del(struct ag_info *ag) 173 { 174 CHECK_AG(); 175 176 if (ag->ag_cors == 0) 177 ag_corsest = ag->ag_fine; 178 else 179 ag->ag_cors->ag_fine = ag->ag_fine; 180 181 if (ag->ag_fine == 0) 182 ag_finest = ag->ag_cors; 183 else 184 ag->ag_fine->ag_cors = ag->ag_cors; 185 186 ag->ag_fine = ag_avail; 187 ag_avail = ag; 188 189 CHECK_AG(); 190 } 191 192 193 /* Flush routes waiting for aggregation. 194 * This must not suppress a route unless it is known that among all 195 * routes with coarser masks that match it, the one with the longest 196 * mask is appropriate. This is ensured by scanning the routes 197 * in lexical order, and with the most restrictive mask first 198 * among routes to the same destination. 199 */ 200 void 201 ag_flush(naddr lim_dst_h, /* flush routes to here */ 202 naddr lim_mask, /* matching this mask */ 203 void (*out)(struct ag_info *)) 204 { 205 struct ag_info *ag, *ag_cors; 206 naddr dst_h; 207 208 209 for (ag = ag_finest; 210 ag != 0 && ag->ag_mask >= lim_mask; 211 ag = ag_cors) { 212 ag_cors = ag->ag_cors; 213 214 /* work on only the specified routes */ 215 dst_h = ag->ag_dst_h; 216 if ((dst_h & lim_mask) != lim_dst_h) 217 continue; 218 219 if (!(ag->ag_state & AGS_SUPPRESS)) 220 ag_out(ag, out); 221 222 else for ( ; ; ag_cors = ag_cors->ag_cors) { 223 /* Look for a route that can suppress the 224 * current route */ 225 if (ag_cors == 0) { 226 /* failed, so output it and look for 227 * another route to work on 228 */ 229 ag_out(ag, out); 230 break; 231 } 232 233 if ((dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h) { 234 /* We found a route with a coarser mask that 235 * aggregates the current target. 236 * 237 * If it has a different next hop, it 238 * cannot replace the target, so output 239 * the target. 240 */ 241 if (ag->ag_gate != ag_cors->ag_gate 242 && !(ag->ag_state & AGS_FINE_GATE) 243 && !(ag_cors->ag_state & AGS_CORS_GATE)) { 244 ag_out(ag, out); 245 break; 246 } 247 248 /* If the coarse route has a good enough 249 * metric, it suppresses the target. 250 * If the suppressed target was redundant, 251 * then mark the suppressor redundant. 252 */ 253 if (ag_cors->ag_pref <= ag->ag_pref) { 254 if (AG_IS_REDUN(ag->ag_state) 255 && ag_cors->ag_mask==ag->ag_mask<<1) { 256 if (ag_cors->ag_dst_h == dst_h) 257 ag_cors->ag_state |= AGS_REDUN0; 258 else 259 ag_cors->ag_state |= AGS_REDUN1; 260 } 261 if (ag->ag_tag != ag_cors->ag_tag) 262 ag_cors->ag_tag = 0; 263 if (ag->ag_nhop != ag_cors->ag_nhop) 264 ag_cors->ag_nhop = 0; 265 break; 266 } 267 } 268 } 269 270 /* That route has either been output or suppressed */ 271 ag_cors = ag->ag_cors; 272 ag_del(ag); 273 } 274 275 CHECK_AG(); 276 } 277 278 279 /* Try to aggregate a route with previous routes. 280 */ 281 void 282 ag_check(naddr dst, 283 naddr mask, 284 naddr gate, 285 naddr nhop, 286 char metric, 287 char pref, 288 u_int new_seqno, 289 u_short tag, 290 u_short state, 291 void (*out)(struct ag_info *)) /* output using this */ 292 { 293 struct ag_info *ag, *nag, *ag_cors; 294 naddr xaddr; 295 int x; 296 297 dst = ntohl(dst); 298 299 /* Punt non-contiguous subnet masks. 300 * 301 * (X & -X) contains a single bit if and only if X is a power of 2. 302 * (X + (X & -X)) == 0 if and only if X is a power of 2. 303 */ 304 if ((mask & -mask) + mask != 0) { 305 struct ag_info nc_ag; 306 307 nc_ag.ag_dst_h = dst; 308 nc_ag.ag_mask = mask; 309 nc_ag.ag_gate = gate; 310 nc_ag.ag_nhop = nhop; 311 nc_ag.ag_metric = metric; 312 nc_ag.ag_pref = pref; 313 nc_ag.ag_tag = tag; 314 nc_ag.ag_state = state; 315 nc_ag.ag_seqno = new_seqno; 316 out(&nc_ag); 317 return; 318 } 319 320 /* Search for the right slot in the aggregation table. 321 */ 322 ag_cors = 0; 323 ag = ag_corsest; 324 while (ag != 0) { 325 if (ag->ag_mask >= mask) 326 break; 327 328 /* Suppress old routes (i.e. combine with compatible routes 329 * with coarser masks) as we look for the right slot in the 330 * aggregation table for the new route. 331 * A route to an address less than the current destination 332 * will not be affected by the current route or any route 333 * seen hereafter. That means it is safe to suppress it. 334 * This check keeps poor routes (e.g. with large hop counts) 335 * from preventing suppression of finer routes. 336 */ 337 if (ag_cors != 0 338 && ag->ag_dst_h < dst 339 && (ag->ag_state & AGS_SUPPRESS) 340 && ag_cors->ag_pref <= ag->ag_pref 341 && (ag->ag_dst_h & ag_cors->ag_mask) == ag_cors->ag_dst_h 342 && (ag_cors->ag_gate == ag->ag_gate 343 || (ag->ag_state & AGS_FINE_GATE) 344 || (ag_cors->ag_state & AGS_CORS_GATE))) { 345 /* If the suppressed target was redundant, 346 * then mark the suppressor redundant. 347 */ 348 if (AG_IS_REDUN(ag->ag_state) 349 && ag_cors->ag_mask == ag->ag_mask<<1) { 350 if (ag_cors->ag_dst_h == dst) 351 ag_cors->ag_state |= AGS_REDUN0; 352 else 353 ag_cors->ag_state |= AGS_REDUN1; 354 } 355 if (ag->ag_tag != ag_cors->ag_tag) 356 ag_cors->ag_tag = 0; 357 if (ag->ag_nhop != ag_cors->ag_nhop) 358 ag_cors->ag_nhop = 0; 359 ag_del(ag); 360 CHECK_AG(); 361 } else { 362 ag_cors = ag; 363 } 364 ag = ag_cors->ag_fine; 365 } 366 367 /* If we find the even/odd twin of the new route, and if the 368 * masks and so forth are equal, we can aggregate them. 369 * We can probably promote one of the pair. 370 * 371 * Since the routes are encountered in lexical order, 372 * the new route must be odd. However, the second or later 373 * times around this loop, it could be the even twin promoted 374 * from the even/odd pair of twins of the finer route. 375 */ 376 while (ag != 0 377 && ag->ag_mask == mask 378 && ((ag->ag_dst_h ^ dst) & (mask<<1)) == 0) { 379 380 /* Here we know the target route and the route in the current 381 * slot have the same netmasks and differ by at most the 382 * last bit. They are either for the same destination, or 383 * for an even/odd pair of destinations. 384 */ 385 if (ag->ag_dst_h == dst) { 386 /* We have two routes to the same destination. 387 * Routes are encountered in lexical order, so a 388 * route is never promoted until the parent route is 389 * already present. So we know that the new route is 390 * a promoted (or aggregated) pair and the route 391 * already in the slot is the explicit route. 392 * 393 * Prefer the best route if their metrics differ, 394 * or the aggregated one if not, following a sort 395 * of longest-match rule. 396 */ 397 if (pref <= ag->ag_pref) { 398 ag->ag_gate = gate; 399 ag->ag_nhop = nhop; 400 ag->ag_tag = tag; 401 ag->ag_metric = metric; 402 ag->ag_pref = pref; 403 if (ag->ag_seqno < new_seqno) 404 ag->ag_seqno = new_seqno; 405 x = ag->ag_state; 406 ag->ag_state = state; 407 state = x; 408 } 409 410 /* Some bits are set if they are set on either route, 411 * except when the route is for an interface. 412 */ 413 if (!(ag->ag_state & AGS_IF)) 414 ag->ag_state |= (state & (AGS_AGGREGATE_EITHER 415 | AGS_REDUN0 416 | AGS_REDUN1)); 417 return; 418 } 419 420 /* If one of the routes can be promoted and the other can 421 * be suppressed, it may be possible to combine them or 422 * worthwhile to promote one. 423 * 424 * Any route that can be promoted is always 425 * marked to be eligible to be suppressed. 426 */ 427 if (!((state & AGS_AGGREGATE) 428 && (ag->ag_state & AGS_SUPPRESS)) 429 && !((ag->ag_state & AGS_AGGREGATE) 430 && (state & AGS_SUPPRESS))) 431 break; 432 433 /* A pair of even/odd twin routes can be combined 434 * if either is redundant, or if they are via the 435 * same gateway and have the same metric. 436 */ 437 if (AG_IS_REDUN(ag->ag_state) 438 || AG_IS_REDUN(state) 439 || (ag->ag_gate == gate 440 && ag->ag_pref == pref 441 && (state & ag->ag_state & AGS_AGGREGATE) != 0)) { 442 443 /* We have both the even and odd pairs. 444 * Since the routes are encountered in order, 445 * the route in the slot must be the even twin. 446 * 447 * Combine and promote (aggregate) the pair of routes. 448 */ 449 if (new_seqno < ag->ag_seqno) 450 new_seqno = ag->ag_seqno; 451 if (!AG_IS_REDUN(state)) 452 state &= ~AGS_REDUN1; 453 if (AG_IS_REDUN(ag->ag_state)) 454 state |= AGS_REDUN0; 455 else 456 state &= ~AGS_REDUN0; 457 state |= (ag->ag_state & AGS_AGGREGATE_EITHER); 458 if (ag->ag_tag != tag) 459 tag = 0; 460 if (ag->ag_nhop != nhop) 461 nhop = 0; 462 463 /* Get rid of the even twin that was already 464 * in the slot. 465 */ 466 ag_del(ag); 467 468 } else if (ag->ag_pref >= pref 469 && (ag->ag_state & AGS_AGGREGATE)) { 470 /* If we cannot combine the pair, maybe the route 471 * with the worse metric can be promoted. 472 * 473 * Promote the old, even twin, by giving its slot 474 * in the table to the new, odd twin. 475 */ 476 ag->ag_dst_h = dst; 477 478 xaddr = ag->ag_gate; 479 ag->ag_gate = gate; 480 gate = xaddr; 481 482 xaddr = ag->ag_nhop; 483 ag->ag_nhop = nhop; 484 nhop = xaddr; 485 486 x = ag->ag_tag; 487 ag->ag_tag = tag; 488 tag = x; 489 490 /* The promoted route is even-redundant only if the 491 * even twin was fully redundant. It is not 492 * odd-redundant because the odd-twin will still be 493 * in the table. 494 */ 495 x = ag->ag_state; 496 if (!AG_IS_REDUN(x)) 497 x &= ~AGS_REDUN0; 498 x &= ~AGS_REDUN1; 499 ag->ag_state = state; 500 state = x; 501 502 x = ag->ag_metric; 503 ag->ag_metric = metric; 504 metric = x; 505 506 x = ag->ag_pref; 507 ag->ag_pref = pref; 508 pref = x; 509 510 /* take the newest sequence number */ 511 if (new_seqno <= ag->ag_seqno) 512 new_seqno = ag->ag_seqno; 513 else 514 ag->ag_seqno = new_seqno; 515 516 } else { 517 if (!(state & AGS_AGGREGATE)) 518 break; /* cannot promote either twin */ 519 520 /* Promote the new, odd twin by shaving its 521 * mask and address. 522 * The promoted route is odd-redundant only if the 523 * odd twin was fully redundant. It is not 524 * even-redundant because the even twin is still in 525 * the table. 526 */ 527 if (!AG_IS_REDUN(state)) 528 state &= ~AGS_REDUN1; 529 state &= ~AGS_REDUN0; 530 if (new_seqno < ag->ag_seqno) 531 new_seqno = ag->ag_seqno; 532 else 533 ag->ag_seqno = new_seqno; 534 } 535 536 mask <<= 1; 537 dst &= mask; 538 539 if (ag_cors == 0) { 540 ag = ag_corsest; 541 break; 542 } 543 ag = ag_cors; 544 ag_cors = ag->ag_cors; 545 } 546 547 /* When we can no longer promote and combine routes, 548 * flush the old route in the target slot. Also flush 549 * any finer routes that we know will never be aggregated by 550 * the new route. 551 * 552 * In case we moved toward coarser masks, 553 * get back where we belong 554 */ 555 if (ag != 0 556 && ag->ag_mask < mask) { 557 ag_cors = ag; 558 ag = ag->ag_fine; 559 } 560 561 /* Empty the target slot 562 */ 563 if (ag != 0 && ag->ag_mask == mask) { 564 ag_flush(ag->ag_dst_h, ag->ag_mask, out); 565 ag = (ag_cors == 0) ? ag_corsest : ag_cors->ag_fine; 566 } 567 568 #ifdef DEBUG_AG 569 (void)fflush(stderr); 570 if (ag == 0 && ag_cors != ag_finest) 571 abort(); 572 if (ag_cors == 0 && ag != ag_corsest) 573 abort(); 574 if (ag != 0 && ag->ag_cors != ag_cors) 575 abort(); 576 if (ag_cors != 0 && ag_cors->ag_fine != ag) 577 abort(); 578 CHECK_AG(); 579 #endif 580 581 /* Save the new route on the end of the table. 582 */ 583 nag = ag_avail; 584 ag_avail = nag->ag_fine; 585 586 nag->ag_dst_h = dst; 587 nag->ag_mask = mask; 588 nag->ag_gate = gate; 589 nag->ag_nhop = nhop; 590 nag->ag_metric = metric; 591 nag->ag_pref = pref; 592 nag->ag_tag = tag; 593 nag->ag_state = state; 594 nag->ag_seqno = new_seqno; 595 596 nag->ag_fine = ag; 597 if (ag != 0) 598 ag->ag_cors = nag; 599 else 600 ag_finest = nag; 601 nag->ag_cors = ag_cors; 602 if (ag_cors == 0) 603 ag_corsest = nag; 604 else 605 ag_cors->ag_fine = nag; 606 CHECK_AG(); 607 } 608 609 610 #define NAME0_LEN 14 611 static const char * 612 rtm_type_name(u_char type) 613 { 614 static const char *rtm_types[] = { 615 "RTM_ADD", 616 "RTM_DELETE", 617 "RTM_CHANGE", 618 "RTM_GET", 619 "RTM_LOSING", 620 "RTM_REDIRECT", 621 "RTM_MISS", 622 "RTM_LOCK", 623 "RTM_OLDADD", 624 "RTM_OLDDEL", 625 "RTM_RESOLVE", 626 "RTM_NEWADDR", 627 "RTM_DELADDR", 628 #ifdef RTM_OIFINFO 629 "RTM_OIFINFO", 630 #endif 631 "RTM_IFINFO", 632 "RTM_NEWMADDR", 633 "RTM_DELMADDR" 634 }; 635 #define NEW_RTM_PAT "RTM type %#x" 636 static char name0[sizeof(NEW_RTM_PAT)+2]; 637 638 639 if (type > sizeof(rtm_types)/sizeof(rtm_types[0]) 640 || type == 0) { 641 snprintf(name0, sizeof(name0), NEW_RTM_PAT, type); 642 return name0; 643 } else { 644 return rtm_types[type-1]; 645 } 646 #undef NEW_RTM_PAT 647 } 648 649 650 /* Trim a mask in a sockaddr 651 * Produce a length of 0 for an address of 0. 652 * Otherwise produce the index of the first zero byte. 653 */ 654 void 655 #ifdef _HAVE_SIN_LEN 656 masktrim(struct sockaddr_in *ap) 657 #else 658 masktrim(struct sockaddr_in_new *ap) 659 #endif 660 { 661 char *cp; 662 663 if (ap->sin_addr.s_addr == 0) { 664 ap->sin_len = 0; 665 return; 666 } 667 cp = (char *)(&ap->sin_addr.s_addr+1); 668 while (*--cp == 0) 669 continue; 670 ap->sin_len = cp - (char*)ap + 1; 671 } 672 673 674 /* Tell the kernel to add, delete or change a route 675 */ 676 static void 677 rtioctl(int action, /* RTM_DELETE, etc */ 678 naddr dst, 679 naddr gate, 680 naddr mask, 681 int metric, 682 int flags) 683 { 684 struct { 685 struct rt_msghdr w_rtm; 686 struct sockaddr_in w_dst; 687 struct sockaddr_in w_gate; 688 #ifdef _HAVE_SA_LEN 689 struct sockaddr_in w_mask; 690 #else 691 struct sockaddr_in_new w_mask; 692 #endif 693 } w; 694 long cc; 695 # define PAT " %-10s %s metric=%d flags=%#x" 696 # define ARGS rtm_type_name(action), rtname(dst,mask,gate), metric, flags 697 698 again: 699 memset(&w, 0, sizeof(w)); 700 w.w_rtm.rtm_msglen = sizeof(w); 701 w.w_rtm.rtm_version = RTM_VERSION; 702 w.w_rtm.rtm_type = action; 703 w.w_rtm.rtm_flags = flags; 704 w.w_rtm.rtm_seq = ++rt_sock_seqno; 705 w.w_rtm.rtm_addrs = RTA_DST|RTA_GATEWAY; 706 if (metric != 0 || action == RTM_CHANGE) { 707 w.w_rtm.rtm_rmx.rmx_hopcount = metric; 708 w.w_rtm.rtm_inits |= RTV_HOPCOUNT; 709 } 710 w.w_dst.sin_family = AF_INET; 711 w.w_dst.sin_addr.s_addr = dst; 712 w.w_gate.sin_family = AF_INET; 713 w.w_gate.sin_addr.s_addr = gate; 714 #ifdef _HAVE_SA_LEN 715 w.w_dst.sin_len = sizeof(w.w_dst); 716 w.w_gate.sin_len = sizeof(w.w_gate); 717 #endif 718 if (mask == HOST_MASK) { 719 w.w_rtm.rtm_flags |= RTF_HOST; 720 w.w_rtm.rtm_msglen -= sizeof(w.w_mask); 721 } else { 722 w.w_rtm.rtm_addrs |= RTA_NETMASK; 723 w.w_mask.sin_addr.s_addr = htonl(mask); 724 #ifdef _HAVE_SA_LEN 725 masktrim(&w.w_mask); 726 if (w.w_mask.sin_len == 0) 727 w.w_mask.sin_len = sizeof(long); 728 w.w_rtm.rtm_msglen -= (sizeof(w.w_mask) - w.w_mask.sin_len); 729 #endif 730 } 731 732 #ifndef NO_INSTALL 733 cc = write(rt_sock, &w, w.w_rtm.rtm_msglen); 734 if (cc < 0) { 735 if (errno == ESRCH 736 && (action == RTM_CHANGE || action == RTM_DELETE)) { 737 trace_act("route disappeared before" PAT, ARGS); 738 if (action == RTM_CHANGE) { 739 action = RTM_ADD; 740 goto again; 741 } 742 return; 743 } 744 msglog("write(rt_sock)" PAT ": %s", ARGS, strerror(errno)); 745 return; 746 } else if (cc != w.w_rtm.rtm_msglen) { 747 msglog("write(rt_sock) wrote %ld instead of %d for" PAT, 748 cc, w.w_rtm.rtm_msglen, ARGS); 749 return; 750 } 751 #endif 752 if (TRACEKERNEL) 753 trace_misc("write kernel" PAT, ARGS); 754 #undef PAT 755 #undef ARGS 756 } 757 758 759 #define KHASH_SIZE 71 /* should be prime */ 760 #define KHASH(a,m) khash_bins[((a) ^ (m)) % KHASH_SIZE] 761 static struct khash { 762 struct khash *k_next; 763 naddr k_dst; 764 naddr k_mask; 765 naddr k_gate; 766 short k_metric; 767 u_short k_state; 768 #define KS_NEW 0x001 769 #define KS_DELETE 0x002 /* need to delete the route */ 770 #define KS_ADD 0x004 /* add to the kernel */ 771 #define KS_CHANGE 0x008 /* tell kernel to change the route */ 772 #define KS_DEL_ADD 0x010 /* delete & add to change the kernel */ 773 #define KS_STATIC 0x020 /* Static flag in kernel */ 774 #define KS_GATEWAY 0x040 /* G flag in kernel */ 775 #define KS_DYNAMIC 0x080 /* result of redirect */ 776 #define KS_DELETED 0x100 /* already deleted from kernel */ 777 #define KS_CHECK 0x200 778 time_t k_keep; 779 #define K_KEEP_LIM 30 780 time_t k_redirect_time; /* when redirected route 1st seen */ 781 } *khash_bins[KHASH_SIZE]; 782 783 784 static struct khash* 785 kern_find(naddr dst, naddr mask, struct khash ***ppk) 786 { 787 struct khash *k, **pk; 788 789 for (pk = &KHASH(dst,mask); (k = *pk) != 0; pk = &k->k_next) { 790 if (k->k_dst == dst && k->k_mask == mask) 791 break; 792 } 793 if (ppk != 0) 794 *ppk = pk; 795 return k; 796 } 797 798 799 static struct khash* 800 kern_add(naddr dst, naddr mask) 801 { 802 struct khash *k, **pk; 803 804 k = kern_find(dst, mask, &pk); 805 if (k != 0) 806 return k; 807 808 k = (struct khash *)rtmalloc(sizeof(*k), "kern_add"); 809 810 memset(k, 0, sizeof(*k)); 811 k->k_dst = dst; 812 k->k_mask = mask; 813 k->k_state = KS_NEW; 814 k->k_keep = now.tv_sec; 815 *pk = k; 816 817 return k; 818 } 819 820 821 /* If a kernel route has a non-zero metric, check that it is still in the 822 * daemon table, and not deleted by interfaces coming and going. 823 */ 824 static void 825 kern_check_static(struct khash *k, 826 struct interface *ifp) 827 { 828 struct rt_entry *rt; 829 struct rt_spare new; 830 831 if (k->k_metric == 0) 832 return; 833 834 memset(&new, 0, sizeof(new)); 835 new.rts_ifp = ifp; 836 new.rts_gate = k->k_gate; 837 new.rts_router = (ifp != 0) ? ifp->int_addr : loopaddr; 838 new.rts_metric = k->k_metric; 839 new.rts_time = now.tv_sec; 840 841 rt = rtget(k->k_dst, k->k_mask); 842 if (rt != 0) { 843 if (!(rt->rt_state & RS_STATIC)) 844 rtchange(rt, rt->rt_state | RS_STATIC, &new, 0); 845 } else { 846 rtadd(k->k_dst, k->k_mask, RS_STATIC, &new); 847 } 848 } 849 850 851 /* operate on a kernel entry 852 */ 853 static void 854 kern_ioctl(struct khash *k, 855 int action, /* RTM_DELETE, etc */ 856 int flags) 857 858 { 859 switch (action) { 860 case RTM_DELETE: 861 k->k_state &= ~KS_DYNAMIC; 862 if (k->k_state & KS_DELETED) 863 return; 864 k->k_state |= KS_DELETED; 865 break; 866 case RTM_ADD: 867 k->k_state &= ~KS_DELETED; 868 break; 869 case RTM_CHANGE: 870 if (k->k_state & KS_DELETED) { 871 action = RTM_ADD; 872 k->k_state &= ~KS_DELETED; 873 } 874 break; 875 } 876 877 rtioctl(action, k->k_dst, k->k_gate, k->k_mask, k->k_metric, flags); 878 } 879 880 881 /* add a route the kernel told us 882 */ 883 static void 884 rtm_add(struct rt_msghdr *rtm, 885 struct rt_addrinfo *info, 886 time_t keep) 887 { 888 struct khash *k; 889 struct interface *ifp; 890 naddr mask; 891 892 893 if (rtm->rtm_flags & RTF_HOST) { 894 mask = HOST_MASK; 895 } else if (INFO_MASK(info) != 0) { 896 mask = ntohl(S_ADDR(INFO_MASK(info))); 897 } else { 898 msglog("ignore %s without mask", rtm_type_name(rtm->rtm_type)); 899 return; 900 } 901 902 k = kern_add(S_ADDR(INFO_DST(info)), mask); 903 if (k->k_state & KS_NEW) 904 k->k_keep = now.tv_sec+keep; 905 if (INFO_GATE(info) == 0) { 906 trace_act("note %s without gateway", 907 rtm_type_name(rtm->rtm_type)); 908 k->k_metric = HOPCNT_INFINITY; 909 } else if (INFO_GATE(info)->sa_family != AF_INET) { 910 trace_act("note %s with gateway AF=%d", 911 rtm_type_name(rtm->rtm_type), 912 INFO_GATE(info)->sa_family); 913 k->k_metric = HOPCNT_INFINITY; 914 } else { 915 k->k_gate = S_ADDR(INFO_GATE(info)); 916 k->k_metric = rtm->rtm_rmx.rmx_hopcount; 917 if (k->k_metric < 0) 918 k->k_metric = 0; 919 else if (k->k_metric > HOPCNT_INFINITY-1) 920 k->k_metric = HOPCNT_INFINITY-1; 921 } 922 k->k_state &= ~(KS_DELETE | KS_ADD | KS_CHANGE | KS_DEL_ADD 923 | KS_DELETED | KS_GATEWAY | KS_STATIC 924 | KS_NEW | KS_CHECK); 925 if (rtm->rtm_flags & RTF_GATEWAY) 926 k->k_state |= KS_GATEWAY; 927 if (rtm->rtm_flags & RTF_STATIC) 928 k->k_state |= KS_STATIC; 929 930 if (0 != (rtm->rtm_flags & (RTF_DYNAMIC | RTF_MODIFIED))) { 931 if (INFO_AUTHOR(info) != 0 932 && INFO_AUTHOR(info)->sa_family == AF_INET) 933 ifp = iflookup(S_ADDR(INFO_AUTHOR(info))); 934 else 935 ifp = 0; 936 if (supplier 937 && (ifp == 0 || !(ifp->int_state & IS_REDIRECT_OK))) { 938 /* Routers are not supposed to listen to redirects, 939 * so delete it if it came via an unknown interface 940 * or the interface does not have special permission. 941 */ 942 k->k_state &= ~KS_DYNAMIC; 943 k->k_state |= KS_DELETE; 944 LIM_SEC(need_kern, 0); 945 trace_act("mark for deletion redirected %s --> %s" 946 " via %s", 947 addrname(k->k_dst, k->k_mask, 0), 948 naddr_ntoa(k->k_gate), 949 ifp ? ifp->int_name : "unknown interface"); 950 } else { 951 k->k_state |= KS_DYNAMIC; 952 k->k_redirect_time = now.tv_sec; 953 trace_act("accept redirected %s --> %s 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 } 958 return; 959 } 960 961 /* If it is not a static route, quit until the next comparison 962 * between the kernel and daemon tables, when it will be deleted. 963 */ 964 if (!(k->k_state & KS_STATIC)) { 965 k->k_state |= KS_DELETE; 966 LIM_SEC(need_kern, k->k_keep); 967 return; 968 } 969 970 /* Put static routes with real metrics into the daemon table so 971 * they can be advertised. 972 * 973 * Find the interface toward the gateway. 974 */ 975 ifp = iflookup(k->k_gate); 976 if (ifp == 0) 977 msglog("static route %s --> %s impossibly lacks ifp", 978 addrname(S_ADDR(INFO_DST(info)), mask, 0), 979 naddr_ntoa(k->k_gate)); 980 981 kern_check_static(k, ifp); 982 } 983 984 985 /* deal with packet loss 986 */ 987 static void 988 rtm_lose(struct rt_msghdr *rtm, 989 struct rt_addrinfo *info) 990 { 991 if (INFO_GATE(info) == 0 992 || INFO_GATE(info)->sa_family != AF_INET) { 993 trace_act("ignore %s without gateway", 994 rtm_type_name(rtm->rtm_type)); 995 return; 996 } 997 998 if (rdisc_ok) 999 rdisc_age(S_ADDR(INFO_GATE(info))); 1000 age(S_ADDR(INFO_GATE(info))); 1001 } 1002 1003 1004 /* Make the gateway slot of an info structure point to something 1005 * useful. If it is not already useful, but it specifies an interface, 1006 * then fill in the sockaddr_in provided and point it there. 1007 */ 1008 static int 1009 get_info_gate(struct sockaddr **sap, 1010 struct sockaddr_in *rsin) 1011 { 1012 struct sockaddr_dl *sdl = (struct sockaddr_dl *)*sap; 1013 struct interface *ifp; 1014 1015 if (sdl == 0) 1016 return 0; 1017 if ((sdl)->sdl_family == AF_INET) 1018 return 1; 1019 if ((sdl)->sdl_family != AF_LINK) 1020 return 0; 1021 1022 ifp = ifwithindex(sdl->sdl_index, 1); 1023 if (ifp == 0) 1024 return 0; 1025 1026 rsin->sin_addr.s_addr = ifp->int_addr; 1027 #ifdef _HAVE_SA_LEN 1028 rsin->sin_len = sizeof(*rsin); 1029 #endif 1030 rsin->sin_family = AF_INET; 1031 *sap = (struct sockaddr*)rsin; 1032 1033 return 1; 1034 } 1035 1036 1037 /* Clean the kernel table by copying it to the daemon image. 1038 * Eventually the daemon will delete any extra routes. 1039 */ 1040 void 1041 flush_kern(void) 1042 { 1043 static char *sysctl_buf; 1044 static size_t sysctl_buf_size = 0; 1045 size_t needed; 1046 int mib[6]; 1047 char *next, *lim; 1048 struct rt_msghdr *rtm; 1049 struct sockaddr_in gate_sin; 1050 struct rt_addrinfo info; 1051 int i; 1052 struct khash *k; 1053 1054 1055 for (i = 0; i < KHASH_SIZE; i++) { 1056 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1057 k->k_state |= KS_CHECK; 1058 } 1059 } 1060 1061 mib[0] = CTL_NET; 1062 mib[1] = PF_ROUTE; 1063 mib[2] = 0; /* protocol */ 1064 mib[3] = 0; /* wildcard address family */ 1065 mib[4] = NET_RT_DUMP; 1066 mib[5] = 0; /* no flags */ 1067 for (;;) { 1068 if ((needed = sysctl_buf_size) != 0) { 1069 if (sysctl(mib, 6, sysctl_buf,&needed, 0, 0) >= 0) 1070 break; 1071 if (errno != ENOMEM && errno != EFAULT) 1072 BADERR(1,"flush_kern: sysctl(RT_DUMP)"); 1073 free(sysctl_buf); 1074 needed = 0; 1075 } 1076 if (sysctl(mib, 6, 0, &needed, 0, 0) < 0) 1077 BADERR(1,"flush_kern: sysctl(RT_DUMP) estimate"); 1078 /* Kludge around the habit of some systems, such as 1079 * BSD/OS 3.1, to not admit how many routes are in the 1080 * kernel, or at least to be quite wrong. 1081 */ 1082 needed += 50*(sizeof(*rtm)+5*sizeof(struct sockaddr)); 1083 sysctl_buf = rtmalloc(sysctl_buf_size = needed, 1084 "flush_kern sysctl(RT_DUMP)"); 1085 } 1086 1087 lim = sysctl_buf + needed; 1088 for (next = sysctl_buf; next < lim; next += rtm->rtm_msglen) { 1089 rtm = (struct rt_msghdr *)next; 1090 if (rtm->rtm_msglen == 0) { 1091 msglog("zero length kernel route at " 1092 " %#lx in buffer %#lx before %#lx", 1093 (u_long)rtm, (u_long)sysctl_buf, (u_long)lim); 1094 break; 1095 } 1096 1097 rt_xaddrs(&info, 1098 (struct sockaddr *)(rtm+1), 1099 (struct sockaddr *)(next + rtm->rtm_msglen), 1100 rtm->rtm_addrs); 1101 1102 if (INFO_DST(&info) == 0 1103 || INFO_DST(&info)->sa_family != AF_INET) 1104 continue; 1105 1106 /* ignore ARP table entries on systems with a merged route 1107 * and ARP table. 1108 */ 1109 if (rtm->rtm_flags & RTF_LLINFO) 1110 continue; 1111 1112 #if defined(RTF_WASCLONED) && defined(__FreeBSD__) 1113 /* ignore cloned routes 1114 */ 1115 if (rtm->rtm_flags & RTF_WASCLONED) 1116 continue; 1117 #endif 1118 1119 /* ignore multicast addresses 1120 */ 1121 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) 1122 continue; 1123 1124 if (!get_info_gate(&INFO_GATE(&info), &gate_sin)) 1125 continue; 1126 1127 /* Note static routes and interface routes, and also 1128 * preload the image of the kernel table so that 1129 * we can later clean it, as well as avoid making 1130 * unneeded changes. Keep the old kernel routes for a 1131 * few seconds to allow a RIP or router-discovery 1132 * response to be heard. 1133 */ 1134 rtm_add(rtm,&info,MIN_WAITTIME); 1135 } 1136 1137 for (i = 0; i < KHASH_SIZE; i++) { 1138 for (k = khash_bins[i]; k != 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 #ifdef RTM_OIFINFO 1227 if (m.r.rtm.rtm_type == RTM_OIFINFO) 1228 continue; /* ignore compat message */ 1229 #endif 1230 1231 strcpy(str, rtm_type_name(m.r.rtm.rtm_type)); 1232 strp = &str[strlen(str)]; 1233 if (m.r.rtm.rtm_type <= RTM_CHANGE) 1234 strp += sprintf(strp," from pid %d",m.r.rtm.rtm_pid); 1235 1236 rt_xaddrs(&info, m.r.addrs, &m.r.addrs[RTAX_MAX], 1237 m.r.rtm.rtm_addrs); 1238 1239 if (INFO_DST(&info) == 0) { 1240 trace_act("ignore %s without dst", str); 1241 continue; 1242 } 1243 1244 if (INFO_DST(&info)->sa_family != AF_INET) { 1245 trace_act("ignore %s for AF %d", str, 1246 INFO_DST(&info)->sa_family); 1247 continue; 1248 } 1249 1250 mask = ((INFO_MASK(&info) != 0) 1251 ? ntohl(S_ADDR(INFO_MASK(&info))) 1252 : (m.r.rtm.rtm_flags & RTF_HOST) 1253 ? HOST_MASK 1254 : std_mask(S_ADDR(INFO_DST(&info)))); 1255 1256 strp += sprintf(strp, ": %s", 1257 addrname(S_ADDR(INFO_DST(&info)), mask, 0)); 1258 1259 if (IN_MULTICAST(ntohl(S_ADDR(INFO_DST(&info))))) { 1260 trace_act("ignore multicast %s", str); 1261 continue; 1262 } 1263 1264 if (m.r.rtm.rtm_flags & RTF_LLINFO) { 1265 trace_act("ignore ARP %s", str); 1266 continue; 1267 } 1268 1269 #if defined(RTF_WASCLONED) && defined(__FreeBSD__) 1270 if (m.r.rtm.rtm_flags & RTF_WASCLONED) { 1271 trace_act("ignore cloned %s", str); 1272 continue; 1273 } 1274 #endif 1275 1276 if (get_info_gate(&INFO_GATE(&info), &gate_sin)) { 1277 gate = S_ADDR(INFO_GATE(&info)); 1278 strp += sprintf(strp, " --> %s", naddr_ntoa(gate)); 1279 } else { 1280 gate = 0; 1281 } 1282 1283 if (INFO_AUTHOR(&info) != 0) 1284 strp += sprintf(strp, " by authority of %s", 1285 saddr_ntoa(INFO_AUTHOR(&info))); 1286 1287 switch (m.r.rtm.rtm_type) { 1288 case RTM_ADD: 1289 case RTM_CHANGE: 1290 case RTM_REDIRECT: 1291 if (m.r.rtm.rtm_errno != 0) { 1292 trace_act("ignore %s with \"%s\" error", 1293 str, strerror(m.r.rtm.rtm_errno)); 1294 } else { 1295 trace_act("%s", str); 1296 rtm_add(&m.r.rtm,&info,0); 1297 } 1298 break; 1299 1300 case RTM_DELETE: 1301 if (m.r.rtm.rtm_errno != 0 1302 && m.r.rtm.rtm_errno != ESRCH) { 1303 trace_act("ignore %s with \"%s\" error", 1304 str, strerror(m.r.rtm.rtm_errno)); 1305 } else { 1306 trace_act("%s", str); 1307 del_static(S_ADDR(INFO_DST(&info)), mask, 1308 gate, 1); 1309 } 1310 break; 1311 1312 case RTM_LOSING: 1313 trace_act("%s", str); 1314 rtm_lose(&m.r.rtm,&info); 1315 break; 1316 1317 default: 1318 trace_act("ignore %s", str); 1319 break; 1320 } 1321 } 1322 } 1323 1324 1325 /* after aggregating, note routes that belong in the kernel 1326 */ 1327 static void 1328 kern_out(struct ag_info *ag) 1329 { 1330 struct khash *k; 1331 1332 1333 /* Do not install bad routes if they are not already present. 1334 * This includes routes that had RS_NET_SYN for interfaces that 1335 * recently died. 1336 */ 1337 if (ag->ag_metric == HOPCNT_INFINITY) { 1338 k = kern_find(htonl(ag->ag_dst_h), ag->ag_mask, 0); 1339 if (k == 0) 1340 return; 1341 } else { 1342 k = kern_add(htonl(ag->ag_dst_h), ag->ag_mask); 1343 } 1344 1345 if (k->k_state & KS_NEW) { 1346 /* will need to add new entry to the kernel table */ 1347 k->k_state = KS_ADD; 1348 if (ag->ag_state & AGS_GATEWAY) 1349 k->k_state |= KS_GATEWAY; 1350 k->k_gate = ag->ag_gate; 1351 k->k_metric = ag->ag_metric; 1352 return; 1353 } 1354 1355 if (k->k_state & KS_STATIC) 1356 return; 1357 1358 /* modify existing kernel entry if necessary */ 1359 if (k->k_gate != ag->ag_gate 1360 || k->k_metric != ag->ag_metric) { 1361 /* Must delete bad interface routes etc. to change them. */ 1362 if (k->k_metric == HOPCNT_INFINITY) 1363 k->k_state |= KS_DEL_ADD; 1364 k->k_gate = ag->ag_gate; 1365 k->k_metric = ag->ag_metric; 1366 k->k_state |= KS_CHANGE; 1367 } 1368 1369 /* If the daemon thinks the route should exist, forget 1370 * about any redirections. 1371 * If the daemon thinks the route should exist, eventually 1372 * override manual intervention by the operator. 1373 */ 1374 if ((k->k_state & (KS_DYNAMIC | KS_DELETED)) != 0) { 1375 k->k_state &= ~KS_DYNAMIC; 1376 k->k_state |= (KS_ADD | KS_DEL_ADD); 1377 } 1378 1379 if ((k->k_state & KS_GATEWAY) 1380 && !(ag->ag_state & AGS_GATEWAY)) { 1381 k->k_state &= ~KS_GATEWAY; 1382 k->k_state |= (KS_ADD | KS_DEL_ADD); 1383 } else if (!(k->k_state & KS_GATEWAY) 1384 && (ag->ag_state & AGS_GATEWAY)) { 1385 k->k_state |= KS_GATEWAY; 1386 k->k_state |= (KS_ADD | KS_DEL_ADD); 1387 } 1388 1389 /* Deleting-and-adding is necessary to change aspects of a route. 1390 * Just delete instead of deleting and then adding a bad route. 1391 * Otherwise, we want to keep the route in the kernel. 1392 */ 1393 if (k->k_metric == HOPCNT_INFINITY 1394 && (k->k_state & KS_DEL_ADD)) 1395 k->k_state |= KS_DELETE; 1396 else 1397 k->k_state &= ~KS_DELETE; 1398 #undef RT 1399 } 1400 1401 1402 /* ARGSUSED */ 1403 static int 1404 walk_kern(struct radix_node *rn, 1405 struct walkarg *argp UNUSED) 1406 { 1407 #define RT ((struct rt_entry *)rn) 1408 char metric, pref; 1409 u_int ags = 0; 1410 1411 1412 /* Do not install synthetic routes */ 1413 if (RT->rt_state & RS_NET_SYN) 1414 return 0; 1415 1416 if (!(RT->rt_state & RS_IF)) { 1417 /* This is an ordinary route, not for an interface. 1418 */ 1419 1420 /* aggregate, ordinary good routes without regard to 1421 * their metric 1422 */ 1423 pref = 1; 1424 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1425 1426 /* Do not install host routes directly to hosts, to avoid 1427 * interfering with ARP entries in the kernel table. 1428 */ 1429 if (RT_ISHOST(RT) 1430 && ntohl(RT->rt_dst) == RT->rt_gate) 1431 return 0; 1432 1433 } else { 1434 /* This is an interface route. 1435 * Do not install routes for "external" remote interfaces. 1436 */ 1437 if (RT->rt_ifp != 0 && (RT->rt_ifp->int_state & IS_EXTERNAL)) 1438 return 0; 1439 1440 /* Interfaces should override received routes. 1441 */ 1442 pref = 0; 1443 ags |= (AGS_IF | AGS_CORS_GATE); 1444 1445 /* If it is not an interface, or an alias for an interface, 1446 * it must be a "gateway." 1447 * 1448 * If it is a "remote" interface, it is also a "gateway" to 1449 * the kernel if is not an alias. 1450 */ 1451 if (RT->rt_ifp == 0 1452 || (RT->rt_ifp->int_state & IS_REMOTE)) 1453 ags |= (AGS_GATEWAY | AGS_SUPPRESS | AGS_AGGREGATE); 1454 } 1455 1456 /* If RIP is off and IRDP is on, let the route to the discovered 1457 * route suppress any RIP routes. Eventually the RIP routes 1458 * will time-out and be deleted. This reaches the steady-state 1459 * quicker. 1460 */ 1461 if ((RT->rt_state & RS_RDISC) && rip_sock < 0) 1462 ags |= AGS_CORS_GATE; 1463 1464 metric = RT->rt_metric; 1465 if (metric == HOPCNT_INFINITY) { 1466 /* if the route is dead, so try hard to aggregate. */ 1467 pref = HOPCNT_INFINITY; 1468 ags |= (AGS_FINE_GATE | AGS_SUPPRESS); 1469 ags &= ~(AGS_IF | AGS_CORS_GATE); 1470 } 1471 1472 ag_check(RT->rt_dst, RT->rt_mask, RT->rt_gate, 0, 1473 metric,pref, 0, 0, ags, kern_out); 1474 return 0; 1475 #undef RT 1476 } 1477 1478 1479 /* Update the kernel table to match the daemon table. 1480 */ 1481 static void 1482 fix_kern(void) 1483 { 1484 int i; 1485 struct khash *k, **pk; 1486 1487 1488 need_kern = age_timer; 1489 1490 /* Walk daemon table, updating the copy of the kernel table. 1491 */ 1492 (void)rn_walktree(rhead, walk_kern, 0); 1493 ag_flush(0,0,kern_out); 1494 1495 for (i = 0; i < KHASH_SIZE; i++) { 1496 for (pk = &khash_bins[i]; (k = *pk) != 0; ) { 1497 /* Do not touch static routes */ 1498 if (k->k_state & KS_STATIC) { 1499 kern_check_static(k,0); 1500 pk = &k->k_next; 1501 continue; 1502 } 1503 1504 /* check hold on routes deleted by the operator */ 1505 if (k->k_keep > now.tv_sec) { 1506 /* ensure we check when the hold is over */ 1507 LIM_SEC(need_kern, k->k_keep); 1508 /* mark for the next cycle */ 1509 k->k_state |= KS_DELETE; 1510 pk = &k->k_next; 1511 continue; 1512 } 1513 1514 if ((k->k_state & KS_DELETE) 1515 && !(k->k_state & KS_DYNAMIC)) { 1516 kern_ioctl(k, RTM_DELETE, 0); 1517 *pk = k->k_next; 1518 free(k); 1519 continue; 1520 } 1521 1522 if (k->k_state & KS_DEL_ADD) 1523 kern_ioctl(k, RTM_DELETE, 0); 1524 1525 if (k->k_state & KS_ADD) { 1526 kern_ioctl(k, RTM_ADD, 1527 ((0 != (k->k_state & (KS_GATEWAY 1528 | KS_DYNAMIC))) 1529 ? RTF_GATEWAY : 0)); 1530 } else if (k->k_state & KS_CHANGE) { 1531 kern_ioctl(k, RTM_CHANGE, 1532 ((0 != (k->k_state & (KS_GATEWAY 1533 | KS_DYNAMIC))) 1534 ? RTF_GATEWAY : 0)); 1535 } 1536 k->k_state &= ~(KS_ADD|KS_CHANGE|KS_DEL_ADD); 1537 1538 /* Mark this route to be deleted in the next cycle. 1539 * This deletes routes that disappear from the 1540 * daemon table, since the normal aging code 1541 * will clear the bit for routes that have not 1542 * disappeared from the daemon table. 1543 */ 1544 k->k_state |= KS_DELETE; 1545 pk = &k->k_next; 1546 } 1547 } 1548 } 1549 1550 1551 /* Delete a static route in the image of the kernel table. 1552 */ 1553 void 1554 del_static(naddr dst, 1555 naddr mask, 1556 naddr gate, 1557 int gone) 1558 { 1559 struct khash *k; 1560 struct rt_entry *rt; 1561 1562 /* Just mark it in the table to be deleted next time the kernel 1563 * table is updated. 1564 * If it has already been deleted, mark it as such, and set its 1565 * keep-timer so that it will not be deleted again for a while. 1566 * This lets the operator delete a route added by the daemon 1567 * and add a replacement. 1568 */ 1569 k = kern_find(dst, mask, 0); 1570 if (k != 0 && (gate == 0 || k->k_gate == gate)) { 1571 k->k_state &= ~(KS_STATIC | KS_DYNAMIC | KS_CHECK); 1572 k->k_state |= KS_DELETE; 1573 if (gone) { 1574 k->k_state |= KS_DELETED; 1575 k->k_keep = now.tv_sec + K_KEEP_LIM; 1576 } 1577 } 1578 1579 rt = rtget(dst, mask); 1580 if (rt != 0 && (rt->rt_state & RS_STATIC)) 1581 rtbad(rt); 1582 } 1583 1584 1585 /* Delete all routes generated from ICMP Redirects that use a given gateway, 1586 * as well as old redirected routes. 1587 */ 1588 void 1589 del_redirects(naddr bad_gate, 1590 time_t old) 1591 { 1592 int i; 1593 struct khash *k; 1594 1595 1596 for (i = 0; i < KHASH_SIZE; i++) { 1597 for (k = khash_bins[i]; k != 0; k = k->k_next) { 1598 if (!(k->k_state & KS_DYNAMIC) 1599 || (k->k_state & KS_STATIC)) 1600 continue; 1601 1602 if (k->k_gate != bad_gate 1603 && k->k_redirect_time > old 1604 && !supplier) 1605 continue; 1606 1607 k->k_state |= KS_DELETE; 1608 k->k_state &= ~KS_DYNAMIC; 1609 need_kern.tv_sec = now.tv_sec; 1610 trace_act("mark redirected %s --> %s for deletion", 1611 addrname(k->k_dst, k->k_mask, 0), 1612 naddr_ntoa(k->k_gate)); 1613 } 1614 } 1615 } 1616 1617 1618 /* Start the daemon tables. 1619 */ 1620 extern int max_keylen; 1621 1622 void 1623 rtinit(void) 1624 { 1625 int i; 1626 struct ag_info *ag; 1627 1628 /* Initialize the radix trees */ 1629 max_keylen = sizeof(struct sockaddr_in); 1630 rn_init(); 1631 rn_inithead((void**)&rhead, 32); 1632 1633 /* mark all of the slots in the table free */ 1634 ag_avail = ag_slots; 1635 for (ag = ag_slots, i = 1; i < NUM_AG_SLOTS; i++) { 1636 ag->ag_fine = ag+1; 1637 ag++; 1638 } 1639 } 1640 1641 1642 #ifdef _HAVE_SIN_LEN 1643 static struct sockaddr_in dst_sock = {sizeof(dst_sock), AF_INET, 0, {0}, {0}}; 1644 static struct sockaddr_in mask_sock = {sizeof(mask_sock), AF_INET, 0, {0}, {0}}; 1645 #else 1646 static struct sockaddr_in_new dst_sock = {_SIN_ADDR_SIZE, AF_INET}; 1647 static struct sockaddr_in_new mask_sock = {_SIN_ADDR_SIZE, AF_INET}; 1648 #endif 1649 1650 1651 static void 1652 set_need_flash(void) 1653 { 1654 if (!need_flash) { 1655 need_flash = 1; 1656 /* Do not send the flash update immediately. Wait a little 1657 * while to hear from other routers. 1658 */ 1659 no_flash.tv_sec = now.tv_sec + MIN_WAITTIME; 1660 } 1661 } 1662 1663 1664 /* Get a particular routing table entry 1665 */ 1666 struct rt_entry * 1667 rtget(naddr dst, naddr mask) 1668 { 1669 struct rt_entry *rt; 1670 1671 dst_sock.sin_addr.s_addr = dst; 1672 mask_sock.sin_addr.s_addr = htonl(mask); 1673 masktrim(&mask_sock); 1674 rt = (struct rt_entry *)rhead->rnh_lookup(&dst_sock,&mask_sock,rhead); 1675 if (!rt 1676 || rt->rt_dst != dst 1677 || rt->rt_mask != mask) 1678 return 0; 1679 1680 return rt; 1681 } 1682 1683 1684 /* Find a route to dst as the kernel would. 1685 */ 1686 struct rt_entry * 1687 rtfind(naddr dst) 1688 { 1689 dst_sock.sin_addr.s_addr = dst; 1690 return (struct rt_entry *)rhead->rnh_matchaddr(&dst_sock, rhead); 1691 } 1692 1693 1694 /* add a route to the table 1695 */ 1696 void 1697 rtadd(naddr dst, 1698 naddr mask, 1699 u_int state, /* rt_state for the entry */ 1700 struct rt_spare *new) 1701 { 1702 struct rt_entry *rt; 1703 naddr smask; 1704 int i; 1705 struct rt_spare *rts; 1706 1707 rt = (struct rt_entry *)rtmalloc(sizeof (*rt), "rtadd"); 1708 memset(rt, 0, sizeof(*rt)); 1709 for (rts = rt->rt_spares, i = NUM_SPARES; i != 0; i--, rts++) 1710 rts->rts_metric = HOPCNT_INFINITY; 1711 1712 rt->rt_nodes->rn_key = (caddr_t)&rt->rt_dst_sock; 1713 rt->rt_dst = dst; 1714 rt->rt_dst_sock.sin_family = AF_INET; 1715 #ifdef _HAVE_SIN_LEN 1716 rt->rt_dst_sock.sin_len = dst_sock.sin_len; 1717 #endif 1718 if (mask != HOST_MASK) { 1719 smask = std_mask(dst); 1720 if ((smask & ~mask) == 0 && mask > smask) 1721 state |= RS_SUBNET; 1722 } 1723 mask_sock.sin_addr.s_addr = htonl(mask); 1724 masktrim(&mask_sock); 1725 rt->rt_mask = mask; 1726 rt->rt_state = state; 1727 rt->rt_spares[0] = *new; 1728 rt->rt_time = now.tv_sec; 1729 rt->rt_poison_metric = HOPCNT_INFINITY; 1730 rt->rt_seqno = update_seqno; 1731 1732 if (++total_routes == MAX_ROUTES) 1733 msglog("have maximum (%d) routes", total_routes); 1734 if (TRACEACTIONS) 1735 trace_add_del("Add", rt); 1736 1737 need_kern.tv_sec = now.tv_sec; 1738 set_need_flash(); 1739 1740 if (0 == rhead->rnh_addaddr(&rt->rt_dst_sock, &mask_sock, 1741 rhead, rt->rt_nodes)) { 1742 msglog("rnh_addaddr() failed for %s mask=%#lx", 1743 naddr_ntoa(dst), (u_long)mask); 1744 free(rt); 1745 } 1746 } 1747 1748 1749 /* notice a changed route 1750 */ 1751 void 1752 rtchange(struct rt_entry *rt, 1753 u_int state, /* new state bits */ 1754 struct rt_spare *new, 1755 char *label) 1756 { 1757 if (rt->rt_metric != new->rts_metric) { 1758 /* Fix the kernel immediately if it seems the route 1759 * has gone bad, since there may be a working route that 1760 * aggregates this route. 1761 */ 1762 if (new->rts_metric == HOPCNT_INFINITY) { 1763 need_kern.tv_sec = now.tv_sec; 1764 if (new->rts_time >= now.tv_sec - EXPIRE_TIME) 1765 new->rts_time = now.tv_sec - EXPIRE_TIME; 1766 } 1767 rt->rt_seqno = update_seqno; 1768 set_need_flash(); 1769 } 1770 1771 if (rt->rt_gate != new->rts_gate) { 1772 need_kern.tv_sec = now.tv_sec; 1773 rt->rt_seqno = update_seqno; 1774 set_need_flash(); 1775 } 1776 1777 state |= (rt->rt_state & RS_SUBNET); 1778 1779 /* Keep various things from deciding ageless routes are stale. 1780 */ 1781 if (!AGE_RT(state, new->rts_ifp)) 1782 new->rts_time = now.tv_sec; 1783 1784 if (TRACEACTIONS) 1785 trace_change(rt, state, new, 1786 label ? label : "Chg "); 1787 1788 rt->rt_state = state; 1789 rt->rt_spares[0] = *new; 1790 } 1791 1792 1793 /* check for a better route among the spares 1794 */ 1795 static struct rt_spare * 1796 rts_better(struct rt_entry *rt) 1797 { 1798 struct rt_spare *rts, *rts1; 1799 int i; 1800 1801 /* find the best alternative among the spares */ 1802 rts = rt->rt_spares+1; 1803 for (i = NUM_SPARES, rts1 = rts+1; i > 2; i--, rts1++) { 1804 if (BETTER_LINK(rt,rts1,rts)) 1805 rts = rts1; 1806 } 1807 1808 return rts; 1809 } 1810 1811 1812 /* switch to a backup route 1813 */ 1814 void 1815 rtswitch(struct rt_entry *rt, 1816 struct rt_spare *rts) 1817 { 1818 struct rt_spare swap; 1819 char label[10]; 1820 1821 1822 /* Do not change permanent routes */ 1823 if (0 != (rt->rt_state & (RS_MHOME | RS_STATIC | RS_RDISC 1824 | RS_NET_SYN | RS_IF))) 1825 return; 1826 1827 /* find the best alternative among the spares */ 1828 if (rts == 0) 1829 rts = rts_better(rt); 1830 1831 /* Do not bother if it is not worthwhile. 1832 */ 1833 if (!BETTER_LINK(rt, rts, rt->rt_spares)) 1834 return; 1835 1836 swap = rt->rt_spares[0]; 1837 (void)sprintf(label, "Use #%d", (int)(rts - rt->rt_spares)); 1838 rtchange(rt, rt->rt_state & ~(RS_NET_SYN | RS_RDISC), rts, label); 1839 if (swap.rts_metric == HOPCNT_INFINITY) { 1840 *rts = rts_empty; 1841 } else { 1842 *rts = swap; 1843 } 1844 } 1845 1846 1847 void 1848 rtdelete(struct rt_entry *rt) 1849 { 1850 struct khash *k; 1851 1852 1853 if (TRACEACTIONS) 1854 trace_add_del("Del", rt); 1855 1856 k = kern_find(rt->rt_dst, rt->rt_mask, 0); 1857 if (k != 0) { 1858 k->k_state |= KS_DELETE; 1859 need_kern.tv_sec = now.tv_sec; 1860 } 1861 1862 dst_sock.sin_addr.s_addr = rt->rt_dst; 1863 mask_sock.sin_addr.s_addr = htonl(rt->rt_mask); 1864 masktrim(&mask_sock); 1865 if (rt != (struct rt_entry *)rhead->rnh_deladdr(&dst_sock, &mask_sock, 1866 rhead)) { 1867 msglog("rnh_deladdr() failed"); 1868 } else { 1869 free(rt); 1870 total_routes--; 1871 } 1872 } 1873 1874 1875 void 1876 rts_delete(struct rt_entry *rt, 1877 struct rt_spare *rts) 1878 { 1879 trace_upslot(rt, rts, &rts_empty); 1880 *rts = rts_empty; 1881 } 1882 1883 1884 /* Get rid of a bad route, and try to switch to a replacement. 1885 */ 1886 void 1887 rtbad(struct rt_entry *rt) 1888 { 1889 struct rt_spare new; 1890 1891 /* Poison the route */ 1892 new = rt->rt_spares[0]; 1893 new.rts_metric = HOPCNT_INFINITY; 1894 rtchange(rt, rt->rt_state & ~(RS_IF | RS_LOCAL | RS_STATIC), &new, 0); 1895 rtswitch(rt, 0); 1896 } 1897 1898 1899 /* Junk a RS_NET_SYN or RS_LOCAL route, 1900 * unless it is needed by another interface. 1901 */ 1902 void 1903 rtbad_sub(struct rt_entry *rt) 1904 { 1905 struct interface *ifp, *ifp1; 1906 struct intnet *intnetp; 1907 u_int state; 1908 1909 1910 ifp1 = 0; 1911 state = 0; 1912 1913 if (rt->rt_state & RS_LOCAL) { 1914 /* Is this the route through loopback for the interface? 1915 * If so, see if it is used by any other interfaces, such 1916 * as a point-to-point interface with the same local address. 1917 */ 1918 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1919 /* Retain it if another interface needs it. 1920 */ 1921 if (ifp->int_addr == rt->rt_ifp->int_addr) { 1922 state |= RS_LOCAL; 1923 ifp1 = ifp; 1924 break; 1925 } 1926 } 1927 1928 } 1929 1930 if (!(state & RS_LOCAL)) { 1931 /* Retain RIPv1 logical network route if there is another 1932 * interface that justifies it. 1933 */ 1934 if (rt->rt_state & RS_NET_SYN) { 1935 for (ifp = ifnet; ifp != 0; ifp = ifp->int_next) { 1936 if ((ifp->int_state & IS_NEED_NET_SYN) 1937 && rt->rt_mask == ifp->int_std_mask 1938 && rt->rt_dst == ifp->int_std_addr) { 1939 state |= RS_NET_SYN; 1940 ifp1 = ifp; 1941 break; 1942 } 1943 } 1944 } 1945 1946 /* or if there is an authority route that needs it. */ 1947 for (intnetp = intnets; 1948 intnetp != 0; 1949 intnetp = intnetp->intnet_next) { 1950 if (intnetp->intnet_addr == rt->rt_dst 1951 && intnetp->intnet_mask == rt->rt_mask) { 1952 state |= (RS_NET_SYN | RS_NET_INT); 1953 break; 1954 } 1955 } 1956 } 1957 1958 if (ifp1 != 0 || (state & RS_NET_SYN)) { 1959 struct rt_spare new = rt->rt_spares[0]; 1960 new.rts_ifp = ifp1; 1961 rtchange(rt, ((rt->rt_state & ~(RS_NET_SYN|RS_LOCAL)) | state), 1962 &new, 0); 1963 } else { 1964 rtbad(rt); 1965 } 1966 } 1967 1968 1969 /* Called while walking the table looking for sick interfaces 1970 * or after a time change. 1971 */ 1972 /* ARGSUSED */ 1973 int 1974 walk_bad(struct radix_node *rn, 1975 struct walkarg *argp UNUSED) 1976 { 1977 #define RT ((struct rt_entry *)rn) 1978 struct rt_spare *rts; 1979 int i; 1980 1981 1982 /* fix any spare routes through the interface 1983 */ 1984 rts = RT->rt_spares; 1985 for (i = NUM_SPARES; i != 1; i--) { 1986 rts++; 1987 if (rts->rts_metric < HOPCNT_INFINITY 1988 && (rts->rts_ifp == 0 1989 || (rts->rts_ifp->int_state & IS_BROKE))) 1990 rts_delete(RT, rts); 1991 } 1992 1993 /* Deal with the main route 1994 */ 1995 /* finished if it has been handled before or if its interface is ok 1996 */ 1997 if (RT->rt_ifp == 0 || !(RT->rt_ifp->int_state & IS_BROKE)) 1998 return 0; 1999 2000 /* Bad routes for other than interfaces are easy. 2001 */ 2002 if (0 == (RT->rt_state & (RS_IF | RS_NET_SYN | RS_LOCAL))) { 2003 rtbad(RT); 2004 return 0; 2005 } 2006 2007 rtbad_sub(RT); 2008 return 0; 2009 #undef RT 2010 } 2011 2012 2013 /* Check the age of an individual route. 2014 */ 2015 /* ARGSUSED */ 2016 static int 2017 walk_age(struct radix_node *rn, 2018 struct walkarg *argp UNUSED) 2019 { 2020 #define RT ((struct rt_entry *)rn) 2021 struct interface *ifp; 2022 struct rt_spare *rts; 2023 int i; 2024 2025 2026 /* age all of the spare routes, including the primary route 2027 * currently in use 2028 */ 2029 rts = RT->rt_spares; 2030 for (i = NUM_SPARES; i != 0; i--, rts++) { 2031 2032 ifp = rts->rts_ifp; 2033 if (i == NUM_SPARES) { 2034 if (!AGE_RT(RT->rt_state, ifp)) { 2035 /* Keep various things from deciding ageless 2036 * routes are stale 2037 */ 2038 rts->rts_time = now.tv_sec; 2039 continue; 2040 } 2041 2042 /* forget RIP routes after RIP has been turned off. 2043 */ 2044 if (rip_sock < 0) { 2045 rtdelete(RT); 2046 return 0; 2047 } 2048 } 2049 2050 /* age failing routes 2051 */ 2052 if (age_bad_gate == rts->rts_gate 2053 && rts->rts_time >= now_stale) { 2054 rts->rts_time -= SUPPLY_INTERVAL; 2055 } 2056 2057 /* trash the spare routes when they go bad */ 2058 if (rts->rts_metric < HOPCNT_INFINITY 2059 && now_garbage > rts->rts_time 2060 && i != NUM_SPARES) 2061 rts_delete(RT, rts); 2062 } 2063 2064 2065 /* finished if the active route is still fresh */ 2066 if (now_stale <= RT->rt_time) 2067 return 0; 2068 2069 /* try to switch to an alternative */ 2070 rtswitch(RT, 0); 2071 2072 /* Delete a dead route after it has been publically mourned. */ 2073 if (now_garbage > RT->rt_time) { 2074 rtdelete(RT); 2075 return 0; 2076 } 2077 2078 /* Start poisoning a bad route before deleting it. */ 2079 if (now.tv_sec - RT->rt_time > EXPIRE_TIME) { 2080 struct rt_spare new = RT->rt_spares[0]; 2081 new.rts_metric = HOPCNT_INFINITY; 2082 rtchange(RT, RT->rt_state, &new, 0); 2083 } 2084 return 0; 2085 } 2086 2087 2088 /* Watch for dead routes and interfaces. 2089 */ 2090 void 2091 age(naddr bad_gate) 2092 { 2093 struct interface *ifp; 2094 int need_query = 0; 2095 2096 /* If not listening to RIP, there is no need to age the routes in 2097 * the table. 2098 */ 2099 age_timer.tv_sec = (now.tv_sec 2100 + ((rip_sock < 0) ? NEVER : SUPPLY_INTERVAL)); 2101 2102 /* Check for dead IS_REMOTE interfaces by timing their 2103 * transmissions. 2104 */ 2105 for (ifp = ifnet; ifp; ifp = ifp->int_next) { 2106 if (!(ifp->int_state & IS_REMOTE)) 2107 continue; 2108 2109 /* ignore unreachable remote interfaces */ 2110 if (!check_remote(ifp)) 2111 continue; 2112 2113 /* Restore remote interface that has become reachable 2114 */ 2115 if (ifp->int_state & IS_BROKE) 2116 if_ok(ifp, "remote "); 2117 2118 if (ifp->int_act_time != NEVER 2119 && now.tv_sec - ifp->int_act_time > EXPIRE_TIME) { 2120 msglog("remote interface %s to %s timed out after" 2121 " %ld:%ld", 2122 ifp->int_name, 2123 naddr_ntoa(ifp->int_dstaddr), 2124 (now.tv_sec - ifp->int_act_time)/60, 2125 (now.tv_sec - ifp->int_act_time)%60); 2126 if_sick(ifp); 2127 } 2128 2129 /* If we have not heard from the other router 2130 * recently, ask it. 2131 */ 2132 if (now.tv_sec >= ifp->int_query_time) { 2133 ifp->int_query_time = NEVER; 2134 need_query = 1; 2135 } 2136 } 2137 2138 /* Age routes. */ 2139 age_bad_gate = bad_gate; 2140 (void)rn_walktree(rhead, walk_age, 0); 2141 2142 /* delete old redirected routes to keep the kernel table small 2143 * and prevent blackholes 2144 */ 2145 del_redirects(bad_gate, now.tv_sec-STALE_TIME); 2146 2147 /* Update the kernel routing table. */ 2148 fix_kern(); 2149 2150 /* poke reticent remote gateways */ 2151 if (need_query) 2152 rip_query(); 2153 } 2154