1 /* $OpenBSD: rtable.c,v 1.69 2019/06/21 17:11:42 mpi Exp $ */ 2 3 /* 4 * Copyright (c) 2014-2016 Martin Pieuchot 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #ifndef _KERNEL 20 #include "kern_compat.h" 21 #else 22 #include <sys/param.h> 23 #include <sys/systm.h> 24 #include <sys/socket.h> 25 #include <sys/malloc.h> 26 #include <sys/queue.h> 27 #include <sys/domain.h> 28 #include <sys/srp.h> 29 #endif 30 31 #include <net/rtable.h> 32 #include <net/route.h> 33 34 /* 35 * Structures used by rtable_get() to retrieve the corresponding 36 * routing table for a given pair of ``af'' and ``rtableid''. 37 * 38 * Note that once allocated routing table heads are never freed. 39 * This way we do not need to reference count them. 40 * 41 * afmap rtmap/dommp 42 * ----------- --------- ----- 43 * | 0 |--------> | 0 | 0 | ... | 0 | Array mapping rtableid (=index) 44 * ----------- --------- ----- to rdomain/loopback (=value). 45 * | AF_INET |. 46 * ----------- `. .---------. .---------. 47 * ... `----> | rtable0 | ... | rtableN | Array of pointers for 48 * ----------- '---------' '---------' IPv4 routing tables 49 * | AF_MPLS | indexed by ``rtableid''. 50 * ----------- 51 */ 52 struct srp *afmap; 53 uint8_t af2idx[AF_MAX+1]; /* To only allocate supported AF */ 54 uint8_t af2idx_max; 55 56 /* Array of routing table pointers. */ 57 struct rtmap { 58 unsigned int limit; 59 void **tbl; 60 }; 61 62 /* 63 * Array of rtableid -> rdomain mapping. 64 * 65 * Only used for the first index as describbed above. 66 */ 67 struct dommp { 68 unsigned int limit; 69 /* 70 * Array to get the routing domain and loopback interface related to 71 * a routing table. Format: 72 * 73 * 8 unused bits | 16 bits for loopback index | 8 bits for rdomain 74 */ 75 unsigned int *value; 76 }; 77 78 unsigned int rtmap_limit = 0; 79 80 void rtmap_init(void); 81 void rtmap_grow(unsigned int, sa_family_t); 82 void rtmap_dtor(void *, void *); 83 84 struct srp_gc rtmap_gc = SRP_GC_INITIALIZER(rtmap_dtor, NULL); 85 86 void rtable_init_backend(void); 87 void *rtable_alloc(unsigned int, unsigned int, unsigned int); 88 void *rtable_get(unsigned int, sa_family_t); 89 90 void 91 rtmap_init(void) 92 { 93 struct domain *dp; 94 int i; 95 96 /* Start with a single table for every domain that requires it. */ 97 for (i = 0; (dp = domains[i]) != NULL; i++) { 98 if (dp->dom_rtoffset == 0) 99 continue; 100 101 rtmap_grow(1, dp->dom_family); 102 } 103 104 /* Initialize the rtableid->rdomain mapping table. */ 105 rtmap_grow(1, 0); 106 107 rtmap_limit = 1; 108 } 109 110 /* 111 * Grow the size of the array of routing table for AF ``af'' to ``nlimit''. 112 */ 113 void 114 rtmap_grow(unsigned int nlimit, sa_family_t af) 115 { 116 struct rtmap *map, *nmap; 117 int i; 118 119 KERNEL_ASSERT_LOCKED(); 120 121 KASSERT(nlimit > rtmap_limit); 122 123 nmap = malloc(sizeof(*nmap), M_RTABLE, M_WAITOK); 124 nmap->limit = nlimit; 125 nmap->tbl = mallocarray(nlimit, sizeof(*nmap[0].tbl), M_RTABLE, 126 M_WAITOK|M_ZERO); 127 128 map = srp_get_locked(&afmap[af2idx[af]]); 129 if (map != NULL) { 130 KASSERT(map->limit == rtmap_limit); 131 132 for (i = 0; i < map->limit; i++) 133 nmap->tbl[i] = map->tbl[i]; 134 } 135 136 srp_update_locked(&rtmap_gc, &afmap[af2idx[af]], nmap); 137 } 138 139 void 140 rtmap_dtor(void *null, void *xmap) 141 { 142 struct rtmap *map = xmap; 143 144 /* 145 * doesnt need to be serialized since this is the last reference 146 * to this map. there's nothing to race against. 147 */ 148 free(map->tbl, M_RTABLE, map->limit * sizeof(*map[0].tbl)); 149 free(map, M_RTABLE, sizeof(*map)); 150 } 151 152 void 153 rtable_init(void) 154 { 155 struct domain *dp; 156 int i; 157 158 KASSERT(sizeof(struct rtmap) == sizeof(struct dommp)); 159 160 /* We use index 0 for the rtable/rdomain map. */ 161 af2idx_max = 1; 162 memset(af2idx, 0, sizeof(af2idx)); 163 164 /* 165 * Compute the maximum supported key length in case the routing 166 * table backend needs it. 167 */ 168 for (i = 0; (dp = domains[i]) != NULL; i++) { 169 if (dp->dom_rtoffset == 0) 170 continue; 171 172 af2idx[dp->dom_family] = af2idx_max++; 173 } 174 rtable_init_backend(); 175 176 /* 177 * Allocate AF-to-id table now that we now how many AFs this 178 * kernel supports. 179 */ 180 afmap = mallocarray(af2idx_max + 1, sizeof(*afmap), M_RTABLE, 181 M_WAITOK|M_ZERO); 182 183 rtmap_init(); 184 185 if (rtable_add(0) != 0) 186 panic("unable to create default routing table"); 187 } 188 189 int 190 rtable_add(unsigned int id) 191 { 192 struct domain *dp; 193 void *tbl; 194 struct rtmap *map; 195 struct dommp *dmm; 196 sa_family_t af; 197 unsigned int off, alen; 198 int i; 199 200 KERNEL_ASSERT_LOCKED(); 201 202 if (id > RT_TABLEID_MAX) 203 return (EINVAL); 204 205 if (rtable_exists(id)) 206 return (EEXIST); 207 208 for (i = 0; (dp = domains[i]) != NULL; i++) { 209 if (dp->dom_rtoffset == 0) 210 continue; 211 212 af = dp->dom_family; 213 off = dp->dom_rtoffset; 214 alen = dp->dom_maxplen; 215 216 if (id >= rtmap_limit) 217 rtmap_grow(id + 1, af); 218 219 tbl = rtable_alloc(id, alen, off); 220 if (tbl == NULL) 221 return (ENOMEM); 222 223 map = srp_get_locked(&afmap[af2idx[af]]); 224 map->tbl[id] = tbl; 225 } 226 227 /* Reflect possible growth. */ 228 if (id >= rtmap_limit) { 229 rtmap_grow(id + 1, 0); 230 rtmap_limit = id + 1; 231 } 232 233 /* Use main rtable/rdomain by default. */ 234 dmm = srp_get_locked(&afmap[0]); 235 dmm->value[id] = 0; 236 237 return (0); 238 } 239 240 void * 241 rtable_get(unsigned int rtableid, sa_family_t af) 242 { 243 struct rtmap *map; 244 void *tbl = NULL; 245 struct srp_ref sr; 246 247 if (af >= nitems(af2idx) || af2idx[af] == 0) 248 return (NULL); 249 250 map = srp_enter(&sr, &afmap[af2idx[af]]); 251 if (rtableid < map->limit) 252 tbl = map->tbl[rtableid]; 253 srp_leave(&sr); 254 255 return (tbl); 256 } 257 258 int 259 rtable_exists(unsigned int rtableid) 260 { 261 struct domain *dp; 262 void *tbl; 263 int i; 264 265 for (i = 0; (dp = domains[i]) != NULL; i++) { 266 if (dp->dom_rtoffset == 0) 267 continue; 268 269 tbl = rtable_get(rtableid, dp->dom_family); 270 if (tbl != NULL) 271 return (1); 272 } 273 274 return (0); 275 } 276 277 int 278 rtable_empty(unsigned int rtableid) 279 { 280 struct domain *dp; 281 int i; 282 struct art_root *tbl; 283 284 for (i = 0; (dp = domains[i]) != NULL; i++) { 285 if (dp->dom_rtoffset == 0) 286 continue; 287 288 tbl = rtable_get(rtableid, dp->dom_family); 289 if (tbl == NULL) 290 continue; 291 if (tbl->ar_root.ref != NULL) 292 return (0); 293 } 294 295 return (1); 296 } 297 298 unsigned int 299 rtable_l2(unsigned int rtableid) 300 { 301 struct dommp *dmm; 302 unsigned int rdomain = 0; 303 struct srp_ref sr; 304 305 dmm = srp_enter(&sr, &afmap[0]); 306 if (rtableid < dmm->limit) 307 rdomain = (dmm->value[rtableid] & RT_TABLEID_MASK); 308 srp_leave(&sr); 309 310 return (rdomain); 311 } 312 313 unsigned int 314 rtable_loindex(unsigned int rtableid) 315 { 316 struct dommp *dmm; 317 unsigned int loifidx = 0; 318 struct srp_ref sr; 319 320 dmm = srp_enter(&sr, &afmap[0]); 321 if (rtableid < dmm->limit) 322 loifidx = (dmm->value[rtableid] >> RT_TABLEID_BITS); 323 srp_leave(&sr); 324 325 return (loifidx); 326 } 327 328 void 329 rtable_l2set(unsigned int rtableid, unsigned int rdomain, unsigned int loifidx) 330 { 331 struct dommp *dmm; 332 unsigned int value; 333 334 KERNEL_ASSERT_LOCKED(); 335 336 if (!rtable_exists(rtableid) || !rtable_exists(rdomain)) 337 return; 338 339 value = (rdomain & RT_TABLEID_MASK) | (loifidx << RT_TABLEID_BITS); 340 341 dmm = srp_get_locked(&afmap[0]); 342 dmm->value[rtableid] = value; 343 } 344 345 346 static inline uint8_t *satoaddr(struct art_root *, struct sockaddr *); 347 348 int an_match(struct art_node *, struct sockaddr *, int); 349 void rtentry_ref(void *, void *); 350 void rtentry_unref(void *, void *); 351 352 void rtable_mpath_insert(struct art_node *, struct rtentry *); 353 354 struct srpl_rc rt_rc = SRPL_RC_INITIALIZER(rtentry_ref, rtentry_unref, NULL); 355 356 void 357 rtable_init_backend(void) 358 { 359 art_init(); 360 } 361 362 void * 363 rtable_alloc(unsigned int rtableid, unsigned int alen, unsigned int off) 364 { 365 return (art_alloc(rtableid, alen, off)); 366 } 367 368 struct rtentry * 369 rtable_lookup(unsigned int rtableid, struct sockaddr *dst, 370 struct sockaddr *mask, struct sockaddr *gateway, uint8_t prio) 371 { 372 struct art_root *ar; 373 struct art_node *an; 374 struct rtentry *rt = NULL; 375 struct srp_ref sr, nsr; 376 uint8_t *addr; 377 int plen; 378 379 ar = rtable_get(rtableid, dst->sa_family); 380 if (ar == NULL) 381 return (NULL); 382 383 addr = satoaddr(ar, dst); 384 385 /* No need for a perfect match. */ 386 if (mask == NULL) { 387 an = art_match(ar, addr, &nsr); 388 if (an == NULL) 389 goto out; 390 } else { 391 plen = rtable_satoplen(dst->sa_family, mask); 392 if (plen == -1) 393 return (NULL); 394 395 an = art_lookup(ar, addr, plen, &nsr); 396 397 /* Make sure we've got a perfect match. */ 398 if (!an_match(an, dst, plen)) 399 goto out; 400 } 401 402 SRPL_FOREACH(rt, &sr, &an->an_rtlist, rt_next) { 403 if (prio != RTP_ANY && 404 (rt->rt_priority & RTP_MASK) != (prio & RTP_MASK)) 405 continue; 406 407 if (gateway == NULL) 408 break; 409 410 if (rt->rt_gateway->sa_len == gateway->sa_len && 411 memcmp(rt->rt_gateway, gateway, gateway->sa_len) == 0) 412 break; 413 } 414 if (rt != NULL) 415 rtref(rt); 416 417 SRPL_LEAVE(&sr); 418 out: 419 srp_leave(&nsr); 420 421 return (rt); 422 } 423 424 struct rtentry * 425 rtable_match(unsigned int rtableid, struct sockaddr *dst, uint32_t *src) 426 { 427 struct art_root *ar; 428 struct art_node *an; 429 struct rtentry *rt = NULL; 430 struct srp_ref sr, nsr; 431 uint8_t *addr; 432 int hash; 433 434 ar = rtable_get(rtableid, dst->sa_family); 435 if (ar == NULL) 436 return (NULL); 437 438 addr = satoaddr(ar, dst); 439 440 an = art_match(ar, addr, &nsr); 441 if (an == NULL) 442 goto out; 443 444 rt = SRPL_FIRST(&sr, &an->an_rtlist); 445 rtref(rt); 446 SRPL_LEAVE(&sr); 447 448 /* Gateway selection by Hash-Threshold (RFC 2992) */ 449 if ((hash = rt_hash(rt, dst, src)) != -1) { 450 struct rtentry *mrt; 451 int threshold, npaths = 0; 452 453 KASSERT(hash <= 0xffff); 454 455 SRPL_FOREACH(mrt, &sr, &an->an_rtlist, rt_next) { 456 /* Only count nexthops with the same priority. */ 457 if (mrt->rt_priority == rt->rt_priority) 458 npaths++; 459 } 460 SRPL_LEAVE(&sr); 461 462 threshold = (0xffff / npaths) + 1; 463 464 /* 465 * we have no protection against concurrent modification of the 466 * route list attached to the node, so we won't necessarily 467 * have the same number of routes. for most modifications, 468 * we'll pick a route that we wouldn't have if we only saw the 469 * list before or after the change. if we were going to use 470 * the last available route, but it got removed, we'll hit 471 * the end of the list and then pick the first route. 472 */ 473 474 mrt = SRPL_FIRST(&sr, &an->an_rtlist); 475 while (hash > threshold && mrt != NULL) { 476 if (mrt->rt_priority == rt->rt_priority) 477 hash -= threshold; 478 mrt = SRPL_FOLLOW(&sr, mrt, rt_next); 479 } 480 481 if (mrt != NULL) { 482 rtref(mrt); 483 rtfree(rt); 484 rt = mrt; 485 } 486 SRPL_LEAVE(&sr); 487 } 488 out: 489 srp_leave(&nsr); 490 return (rt); 491 } 492 493 int 494 rtable_insert(unsigned int rtableid, struct sockaddr *dst, 495 struct sockaddr *mask, struct sockaddr *gateway, uint8_t prio, 496 struct rtentry *rt) 497 { 498 struct rtentry *mrt; 499 struct srp_ref sr; 500 struct art_root *ar; 501 struct art_node *an, *prev; 502 uint8_t *addr; 503 int plen; 504 unsigned int rt_flags; 505 int error = 0; 506 507 ar = rtable_get(rtableid, dst->sa_family); 508 if (ar == NULL) 509 return (EAFNOSUPPORT); 510 511 addr = satoaddr(ar, dst); 512 plen = rtable_satoplen(dst->sa_family, mask); 513 if (plen == -1) 514 return (EINVAL); 515 516 rtref(rt); /* guarantee rtfree won't do anything during insert */ 517 rw_enter_write(&ar->ar_lock); 518 519 /* Do not permit exactly the same dst/mask/gw pair. */ 520 an = art_lookup(ar, addr, plen, &sr); 521 srp_leave(&sr); /* an can't go away while we have the lock */ 522 if (an_match(an, dst, plen)) { 523 struct rtentry *mrt; 524 int mpathok = ISSET(rt->rt_flags, RTF_MPATH); 525 526 SRPL_FOREACH_LOCKED(mrt, &an->an_rtlist, rt_next) { 527 if (prio != RTP_ANY && 528 (mrt->rt_priority & RTP_MASK) != (prio & RTP_MASK)) 529 continue; 530 531 if (!mpathok || 532 (mrt->rt_gateway->sa_len == gateway->sa_len && 533 !memcmp(mrt->rt_gateway, gateway, gateway->sa_len))){ 534 error = EEXIST; 535 goto leave; 536 } 537 } 538 } 539 540 an = art_get(dst, plen); 541 if (an == NULL) { 542 error = ENOBUFS; 543 goto leave; 544 } 545 546 /* prepare for immediate operation if insert succeeds */ 547 rt_flags = rt->rt_flags; 548 rt->rt_flags &= ~RTF_MPATH; 549 rt->rt_dest = dst; 550 rt->rt_plen = plen; 551 SRPL_INSERT_HEAD_LOCKED(&rt_rc, &an->an_rtlist, rt, rt_next); 552 553 prev = art_insert(ar, an, addr, plen); 554 if (prev != an) { 555 SRPL_REMOVE_LOCKED(&rt_rc, &an->an_rtlist, rt, rtentry, 556 rt_next); 557 rt->rt_flags = rt_flags; 558 art_put(an); 559 560 if (prev == NULL) { 561 error = ESRCH; 562 goto leave; 563 } 564 565 an = prev; 566 567 mrt = SRPL_FIRST_LOCKED(&an->an_rtlist); 568 KASSERT(mrt != NULL); 569 KASSERT((rt->rt_flags & RTF_MPATH) || mrt->rt_priority != prio); 570 571 /* 572 * An ART node with the same destination/netmask already 573 * exists, MPATH conflict must have been already checked. 574 */ 575 if (rt->rt_flags & RTF_MPATH) { 576 /* 577 * Only keep the RTF_MPATH flag if two routes have 578 * the same gateway. 579 */ 580 rt->rt_flags &= ~RTF_MPATH; 581 SRPL_FOREACH_LOCKED(mrt, &an->an_rtlist, rt_next) { 582 if (mrt->rt_priority == prio) { 583 mrt->rt_flags |= RTF_MPATH; 584 rt->rt_flags |= RTF_MPATH; 585 } 586 } 587 } 588 589 /* Put newly inserted entry at the right place. */ 590 rtable_mpath_insert(an, rt); 591 } 592 leave: 593 rw_exit_write(&ar->ar_lock); 594 rtfree(rt); 595 return (error); 596 } 597 598 int 599 rtable_delete(unsigned int rtableid, struct sockaddr *dst, 600 struct sockaddr *mask, struct rtentry *rt) 601 { 602 struct art_root *ar; 603 struct art_node *an; 604 struct srp_ref sr; 605 uint8_t *addr; 606 int plen; 607 struct rtentry *mrt; 608 int npaths = 0; 609 int error = 0; 610 611 ar = rtable_get(rtableid, dst->sa_family); 612 if (ar == NULL) 613 return (EAFNOSUPPORT); 614 615 addr = satoaddr(ar, dst); 616 plen = rtable_satoplen(dst->sa_family, mask); 617 if (plen == -1) 618 return (EINVAL); 619 620 rtref(rt); /* guarantee rtfree won't do anything under ar_lock */ 621 rw_enter_write(&ar->ar_lock); 622 an = art_lookup(ar, addr, plen, &sr); 623 srp_leave(&sr); /* an can't go away while we have the lock */ 624 625 /* Make sure we've got a perfect match. */ 626 if (!an_match(an, dst, plen)) { 627 error = ESRCH; 628 goto leave; 629 } 630 631 /* 632 * If other multipath route entries are still attached to 633 * this ART node we only have to unlink it. 634 */ 635 SRPL_FOREACH_LOCKED(mrt, &an->an_rtlist, rt_next) 636 npaths++; 637 638 if (npaths > 1) { 639 KASSERT(rt->rt_refcnt >= 1); 640 SRPL_REMOVE_LOCKED(&rt_rc, &an->an_rtlist, rt, rtentry, 641 rt_next); 642 643 mrt = SRPL_FIRST_LOCKED(&an->an_rtlist); 644 if (npaths == 2) 645 mrt->rt_flags &= ~RTF_MPATH; 646 647 goto leave; 648 } 649 650 if (art_delete(ar, an, addr, plen) == NULL) 651 panic("art_delete failed to find node %p", an); 652 653 KASSERT(rt->rt_refcnt >= 1); 654 SRPL_REMOVE_LOCKED(&rt_rc, &an->an_rtlist, rt, rtentry, rt_next); 655 art_put(an); 656 657 leave: 658 rw_exit_write(&ar->ar_lock); 659 rtfree(rt); 660 661 return (error); 662 } 663 664 struct rtable_walk_cookie { 665 int (*rwc_func)(struct rtentry *, void *, unsigned int); 666 void *rwc_arg; 667 struct rtentry **rwc_prt; 668 unsigned int rwc_rid; 669 }; 670 671 /* 672 * Helper for rtable_walk to keep the ART code free from any "struct rtentry". 673 */ 674 int 675 rtable_walk_helper(struct art_node *an, void *xrwc) 676 { 677 struct srp_ref sr; 678 struct rtable_walk_cookie *rwc = xrwc; 679 struct rtentry *rt; 680 int error = 0; 681 682 SRPL_FOREACH(rt, &sr, &an->an_rtlist, rt_next) { 683 error = (*rwc->rwc_func)(rt, rwc->rwc_arg, rwc->rwc_rid); 684 if (error != 0) 685 break; 686 } 687 if (rwc->rwc_prt != NULL && rt != NULL) { 688 rtref(rt); 689 *rwc->rwc_prt = rt; 690 } 691 SRPL_LEAVE(&sr); 692 693 return (error); 694 } 695 696 int 697 rtable_walk(unsigned int rtableid, sa_family_t af, struct rtentry **prt, 698 int (*func)(struct rtentry *, void *, unsigned int), void *arg) 699 { 700 struct art_root *ar; 701 struct rtable_walk_cookie rwc; 702 int error; 703 704 ar = rtable_get(rtableid, af); 705 if (ar == NULL) 706 return (EAFNOSUPPORT); 707 708 rwc.rwc_func = func; 709 rwc.rwc_arg = arg; 710 rwc.rwc_prt = prt; 711 rwc.rwc_rid = rtableid; 712 713 error = art_walk(ar, rtable_walk_helper, &rwc); 714 715 return (error); 716 } 717 718 struct rtentry * 719 rtable_iterate(struct rtentry *rt0) 720 { 721 struct rtentry *rt = NULL; 722 struct srp_ref sr; 723 724 rt = SRPL_NEXT(&sr, rt0, rt_next); 725 if (rt != NULL) 726 rtref(rt); 727 SRPL_LEAVE(&sr); 728 rtfree(rt0); 729 return (rt); 730 } 731 732 int 733 rtable_mpath_capable(unsigned int rtableid, sa_family_t af) 734 { 735 return (1); 736 } 737 738 int 739 rtable_mpath_reprio(unsigned int rtableid, struct sockaddr *dst, 740 int plen, uint8_t prio, struct rtentry *rt) 741 { 742 struct art_root *ar; 743 struct art_node *an; 744 struct srp_ref sr; 745 uint8_t *addr; 746 int error = 0; 747 748 ar = rtable_get(rtableid, dst->sa_family); 749 if (ar == NULL) 750 return (EAFNOSUPPORT); 751 752 addr = satoaddr(ar, dst); 753 754 rw_enter_write(&ar->ar_lock); 755 an = art_lookup(ar, addr, plen, &sr); 756 srp_leave(&sr); /* an can't go away while we have the lock */ 757 758 /* Make sure we've got a perfect match. */ 759 if (!an_match(an, dst, plen)) { 760 error = ESRCH; 761 } else if (SRPL_FIRST_LOCKED(&an->an_rtlist) == rt && 762 SRPL_NEXT_LOCKED(rt, rt_next) == NULL) { 763 /* 764 * If there's only one entry on the list do not go 765 * through an insert/remove cycle. This is done to 766 * guarantee that ``an->an_rtlist'' is never empty 767 * when a node is in the tree. 768 */ 769 rt->rt_priority = prio; 770 } else { 771 rtref(rt); /* keep rt alive in between remove and insert */ 772 SRPL_REMOVE_LOCKED(&rt_rc, &an->an_rtlist, 773 rt, rtentry, rt_next); 774 rt->rt_priority = prio; 775 rtable_mpath_insert(an, rt); 776 rtfree(rt); 777 error = EAGAIN; 778 } 779 rw_exit_write(&ar->ar_lock); 780 781 return (error); 782 } 783 784 void 785 rtable_mpath_insert(struct art_node *an, struct rtentry *rt) 786 { 787 struct rtentry *mrt, *prt = NULL; 788 uint8_t prio = rt->rt_priority; 789 790 if ((mrt = SRPL_FIRST_LOCKED(&an->an_rtlist)) == NULL) { 791 SRPL_INSERT_HEAD_LOCKED(&rt_rc, &an->an_rtlist, rt, rt_next); 792 return; 793 } 794 795 /* Iterate until we find the route to be placed after ``rt''. */ 796 while (mrt->rt_priority <= prio && SRPL_NEXT_LOCKED(mrt, rt_next)) { 797 prt = mrt; 798 mrt = SRPL_NEXT_LOCKED(mrt, rt_next); 799 } 800 801 if (mrt->rt_priority <= prio) { 802 SRPL_INSERT_AFTER_LOCKED(&rt_rc, mrt, rt, rt_next); 803 } else if (prt != NULL) { 804 SRPL_INSERT_AFTER_LOCKED(&rt_rc, prt, rt, rt_next); 805 } else { 806 SRPL_INSERT_HEAD_LOCKED(&rt_rc, &an->an_rtlist, rt, rt_next); 807 } 808 } 809 810 /* 811 * Returns 1 if ``an'' perfectly matches (``dst'', ``plen''), 0 otherwise. 812 */ 813 int 814 an_match(struct art_node *an, struct sockaddr *dst, int plen) 815 { 816 struct rtentry *rt; 817 struct srp_ref sr; 818 int match; 819 820 if (an == NULL || an->an_plen != plen) 821 return (0); 822 823 rt = SRPL_FIRST(&sr, &an->an_rtlist); 824 match = (memcmp(rt->rt_dest, dst, dst->sa_len) == 0); 825 SRPL_LEAVE(&sr); 826 827 return (match); 828 } 829 830 void 831 rtentry_ref(void *null, void *xrt) 832 { 833 struct rtentry *rt = xrt; 834 835 rtref(rt); 836 } 837 838 void 839 rtentry_unref(void *null, void *xrt) 840 { 841 struct rtentry *rt = xrt; 842 843 rtfree(rt); 844 } 845 846 /* 847 * Return a pointer to the address (key). This is an heritage from the 848 * BSD radix tree needed to skip the non-address fields from the flavor 849 * of "struct sockaddr" used by this routing table. 850 */ 851 static inline uint8_t * 852 satoaddr(struct art_root *at, struct sockaddr *sa) 853 { 854 return (((uint8_t *)sa) + at->ar_off); 855 } 856 857 /* 858 * Return the prefix length of a mask. 859 */ 860 int 861 rtable_satoplen(sa_family_t af, struct sockaddr *mask) 862 { 863 struct domain *dp; 864 uint8_t *ap, *ep; 865 int mlen, plen = 0; 866 int i; 867 868 for (i = 0; (dp = domains[i]) != NULL; i++) { 869 if (dp->dom_rtoffset == 0) 870 continue; 871 872 if (af == dp->dom_family) 873 break; 874 } 875 if (dp == NULL) 876 return (-1); 877 878 /* Host route */ 879 if (mask == NULL) 880 return (dp->dom_maxplen); 881 882 mlen = mask->sa_len; 883 884 /* Default route */ 885 if (mlen == 0) 886 return (0); 887 888 ap = (uint8_t *)((uint8_t *)mask) + dp->dom_rtoffset; 889 ep = (uint8_t *)((uint8_t *)mask) + mlen; 890 if (ap > ep) 891 return (-1); 892 893 /* Trim trailing zeroes. */ 894 while (ap < ep && ep[-1] == 0) 895 ep--; 896 897 if (ap == ep) 898 return (0); 899 900 /* "Beauty" adapted from sbin/route/show.c ... */ 901 while (ap < ep) { 902 switch (*ap++) { 903 case 0xff: 904 plen += 8; 905 break; 906 case 0xfe: 907 plen += 7; 908 goto out; 909 case 0xfc: 910 plen += 6; 911 goto out; 912 case 0xf8: 913 plen += 5; 914 goto out; 915 case 0xf0: 916 plen += 4; 917 goto out; 918 case 0xe0: 919 plen += 3; 920 goto out; 921 case 0xc0: 922 plen += 2; 923 goto out; 924 case 0x80: 925 plen += 1; 926 goto out; 927 default: 928 /* Non contiguous mask. */ 929 return (-1); 930 } 931 } 932 933 out: 934 if (plen > dp->dom_maxplen || ap != ep) 935 return -1; 936 937 return (plen); 938 } 939