1 /* $OpenBSD: kroute.c,v 1.37 2025/01/02 06:35:57 anton Exp $ */ 2 3 /* 4 * Copyright (c) 2004 Esben Norby <norby@openbsd.org> 5 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/types.h> 21 #include <sys/socket.h> 22 #include <sys/sysctl.h> 23 #include <sys/tree.h> 24 #include <sys/uio.h> 25 #include <netinet/in.h> 26 #include <arpa/inet.h> 27 #include <net/if.h> 28 #include <net/if_dl.h> 29 #include <net/if_types.h> 30 #include <net/route.h> 31 #include <err.h> 32 #include <errno.h> 33 #include <fcntl.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 #include <unistd.h> 38 39 #include "rip.h" 40 #include "ripd.h" 41 #include "log.h" 42 43 struct { 44 u_int32_t rtseq; 45 pid_t pid; 46 int fib_sync; 47 u_int8_t fib_prio; 48 int fd; 49 struct event ev; 50 u_int rdomain; 51 } kr_state; 52 53 struct kroute_node { 54 RB_ENTRY(kroute_node) entry; 55 struct kroute r; 56 }; 57 58 struct kif_node { 59 RB_ENTRY(kif_node) entry; 60 struct kif k; 61 }; 62 63 void kr_redistribute(int, struct kroute *); 64 int kroute_compare(struct kroute_node *, struct kroute_node *); 65 int kif_compare(struct kif_node *, struct kif_node *); 66 int kr_change_fib(struct kroute_node *, struct kroute *, int); 67 68 struct kroute_node *kroute_find(in_addr_t, in_addr_t, u_int8_t); 69 int kroute_insert(struct kroute_node *); 70 int kroute_remove(struct kroute_node *); 71 void kroute_clear(void); 72 73 struct kif_node *kif_find(int); 74 int kif_insert(struct kif_node *); 75 int kif_remove(struct kif_node *); 76 void kif_clear(void); 77 int kif_validate(int); 78 79 struct kroute_node *kroute_match(in_addr_t); 80 81 int protect_lo(void); 82 u_int8_t prefixlen_classful(in_addr_t); 83 void get_rtaddrs(int, struct sockaddr *, struct sockaddr **); 84 void if_change(u_short, int, struct if_data *); 85 void if_announce(void *); 86 87 int send_rtmsg(int, int, struct kroute *); 88 int dispatch_rtmsg(void); 89 int fetchtable(void); 90 int fetchifs(int); 91 92 RB_HEAD(kroute_tree, kroute_node) krt; 93 RB_PROTOTYPE(kroute_tree, kroute_node, entry, kroute_compare) 94 RB_GENERATE(kroute_tree, kroute_node, entry, kroute_compare) 95 96 RB_HEAD(kif_tree, kif_node) kit; 97 RB_PROTOTYPE(kif_tree, kif_node, entry, kif_compare) 98 RB_GENERATE(kif_tree, kif_node, entry, kif_compare) 99 100 int 101 kif_init(void) 102 { 103 RB_INIT(&kit); 104 105 if (fetchifs(0) == -1) 106 return (-1); 107 108 return (0); 109 } 110 111 int 112 kr_init(int fs, u_int rdomain, u_int8_t fib_prio) 113 { 114 int opt = 0, rcvbuf, default_rcvbuf; 115 socklen_t optlen; 116 117 if ((kr_state.fd = socket(AF_ROUTE, 118 SOCK_RAW | SOCK_CLOEXEC | SOCK_NONBLOCK, 0)) == -1) { 119 log_warn("kr_init: socket"); 120 return (-1); 121 } 122 123 /* not interested in my own messages */ 124 if (setsockopt(kr_state.fd, SOL_SOCKET, SO_USELOOPBACK, 125 &opt, sizeof(opt)) == -1) 126 log_warn("kr_init: setsockopt"); /* not fatal */ 127 128 /* grow receive buffer, don't wanna miss messages */ 129 optlen = sizeof(default_rcvbuf); 130 if (getsockopt(kr_state.fd, SOL_SOCKET, SO_RCVBUF, 131 &default_rcvbuf, &optlen) == -1) 132 log_warn("kr_init getsockopt SOL_SOCKET SO_RCVBUF"); 133 else 134 for (rcvbuf = MAX_RTSOCK_BUF; 135 rcvbuf > default_rcvbuf && 136 setsockopt(kr_state.fd, SOL_SOCKET, SO_RCVBUF, 137 &rcvbuf, sizeof(rcvbuf)) == -1 && errno == ENOBUFS; 138 rcvbuf /= 2) 139 ; /* nothing */ 140 141 kr_state.pid = getpid(); 142 kr_state.rtseq = 1; 143 kr_state.fib_prio = fib_prio; 144 145 RB_INIT(&krt); 146 147 if (fetchtable() == -1) 148 return (-1); 149 150 if (protect_lo() == -1) 151 return (-1); 152 153 kr_state.fib_sync = fs; /* now set correct sync mode */ 154 kr_state.rdomain = rdomain; 155 156 event_set(&kr_state.ev, kr_state.fd, EV_READ | EV_PERSIST, 157 kr_dispatch_msg, NULL); 158 event_add(&kr_state.ev, NULL); 159 160 return (0); 161 } 162 163 int 164 kr_change_fib(struct kroute_node *kr, struct kroute *kroute, int action) 165 { 166 /* nexthop within 127/8 -> ignore silently */ 167 if ((kroute->nexthop.s_addr & htonl(IN_CLASSA_NET)) == 168 htonl(INADDR_LOOPBACK & IN_CLASSA_NET)) 169 return (0); 170 171 if (send_rtmsg(kr_state.fd, action, kroute) == -1) 172 return (-1); 173 174 if (action == RTM_ADD) { 175 if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL) 176 fatal("kr_change_fib"); 177 178 kr->r.prefix.s_addr = kroute->prefix.s_addr; 179 kr->r.netmask.s_addr = kroute->netmask.s_addr; 180 kr->r.nexthop.s_addr = kroute->nexthop.s_addr; 181 kr->r.flags = kroute->flags |= F_RIPD_INSERTED; 182 kr->r.priority = kr_state.fib_prio; 183 184 if (kroute_insert(kr) == -1) { 185 log_debug("kr_update_fib: cannot insert %s", 186 inet_ntoa(kroute->nexthop)); 187 } 188 } else 189 kr->r.nexthop.s_addr = kroute->nexthop.s_addr; 190 191 return (0); 192 } 193 194 int 195 kr_change(struct kroute *kroute) 196 { 197 struct kroute_node *kr; 198 int action = RTM_ADD; 199 200 kr = kroute_find(kroute->prefix.s_addr, kroute->netmask.s_addr, 201 kr_state.fib_prio); 202 if (kr != NULL) 203 action = RTM_CHANGE; 204 205 return (kr_change_fib(kr, kroute, action)); 206 } 207 208 int 209 kr_delete(struct kroute *kroute) 210 { 211 struct kroute_node *kr; 212 213 kr = kroute_find(kroute->prefix.s_addr, kroute->netmask.s_addr, 214 kr_state.fib_prio); 215 if (kr == NULL) 216 return (0); 217 218 if (kr->r.priority != kr_state.fib_prio) 219 log_warn("kr_delete_fib: %s/%d has wrong priority %d", 220 inet_ntoa(kr->r.prefix), mask2prefixlen(kr->r.netmask.s_addr), 221 kr->r.priority); 222 223 if (send_rtmsg(kr_state.fd, RTM_DELETE, kroute) == -1) 224 return (-1); 225 226 if (kroute_remove(kr) == -1) 227 return (-1); 228 229 return (0); 230 } 231 232 void 233 kr_shutdown(void) 234 { 235 kr_fib_decouple(); 236 237 kroute_clear(); 238 kif_clear(); 239 } 240 241 void 242 kr_fib_couple(void) 243 { 244 struct kroute_node *kr; 245 246 if (kr_state.fib_sync == 1) /* already coupled */ 247 return; 248 249 kr_state.fib_sync = 1; 250 251 RB_FOREACH(kr, kroute_tree, &krt) 252 if (kr->r.priority == kr_state.fib_prio) 253 send_rtmsg(kr_state.fd, RTM_ADD, &kr->r); 254 255 log_info("kernel routing table coupled"); 256 } 257 258 void 259 kr_fib_decouple(void) 260 { 261 struct kroute_node *kr; 262 263 if (kr_state.fib_sync == 0) /* already decoupled */ 264 return; 265 266 RB_FOREACH(kr, kroute_tree, &krt) 267 if (kr->r.priority == kr_state.fib_prio) 268 send_rtmsg(kr_state.fd, RTM_DELETE, &kr->r); 269 270 kr_state.fib_sync = 0; 271 272 log_info("kernel routing table decoupled"); 273 } 274 275 void 276 kr_dispatch_msg(int fd, short event, void *bula) 277 { 278 dispatch_rtmsg(); 279 } 280 281 void 282 kr_show_route(struct imsg *imsg) 283 { 284 struct kroute_node *kr; 285 int flags; 286 struct in_addr addr; 287 288 switch (imsg->hdr.type) { 289 case IMSG_CTL_KROUTE: 290 if (imsg->hdr.len != IMSG_HEADER_SIZE + sizeof(flags)) { 291 log_warnx("kr_show_route: wrong imsg len"); 292 return; 293 } 294 memcpy(&flags, imsg->data, sizeof(flags)); 295 RB_FOREACH(kr, kroute_tree, &krt) 296 if (!flags || kr->r.flags & flags) { 297 main_imsg_compose_ripe(IMSG_CTL_KROUTE, 298 imsg->hdr.pid, &kr->r, sizeof(kr->r)); 299 } 300 break; 301 case IMSG_CTL_KROUTE_ADDR: 302 if (imsg->hdr.len != IMSG_HEADER_SIZE + 303 sizeof(struct in_addr)) { 304 log_warnx("kr_show_route: wrong imsg len"); 305 return; 306 } 307 memcpy(&addr, imsg->data, sizeof(addr)); 308 kr = NULL; 309 kr = kroute_match(addr.s_addr); 310 if (kr != NULL) 311 main_imsg_compose_ripe(IMSG_CTL_KROUTE, imsg->hdr.pid, 312 &kr->r, sizeof(kr->r)); 313 break; 314 default: 315 log_debug("kr_show_route: error handling imsg"); 316 break; 317 } 318 319 main_imsg_compose_ripe(IMSG_CTL_END, imsg->hdr.pid, NULL, 0); 320 } 321 322 void 323 kr_ifinfo(char *ifname, pid_t pid) 324 { 325 struct kif_node *kif; 326 327 RB_FOREACH(kif, kif_tree, &kit) 328 if (ifname == NULL || !strcmp(ifname, kif->k.ifname)) { 329 main_imsg_compose_ripe(IMSG_CTL_IFINFO, 330 pid, &kif->k, sizeof(kif->k)); 331 } 332 333 main_imsg_compose_ripe(IMSG_CTL_END, pid, NULL, 0); 334 } 335 336 void 337 kr_redistribute(int type, struct kroute *kr) 338 { 339 u_int32_t a; 340 341 342 if (type == IMSG_NETWORK_DEL) { 343 dont_redistribute: 344 /* was the route redistributed? */ 345 if (kr->flags & F_REDISTRIBUTED) { 346 /* remove redistributed flag */ 347 kr->flags &= ~F_REDISTRIBUTED; 348 main_imsg_compose_rde(type, 0, kr, 349 sizeof(struct kroute)); 350 } 351 return; 352 } 353 354 /* interface is not up and running so don't announce */ 355 if (kr->flags & F_DOWN) 356 return; 357 358 /* 359 * We consider the loopback net and multicast addresses 360 * as not redistributable. 361 */ 362 a = ntohl(kr->prefix.s_addr); 363 if (IN_MULTICAST(a) || (a >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) 364 return; 365 /* 366 * Consider networks with nexthop loopback as not redistributable 367 * unless it is a reject or blackhole route. 368 */ 369 if (kr->nexthop.s_addr == htonl(INADDR_LOOPBACK) && 370 !(kr->flags & (F_BLACKHOLE|F_REJECT))) 371 return; 372 373 /* Should we redistribute this route? */ 374 if (!rip_redistribute(kr)) 375 goto dont_redistribute; 376 377 /* Does not matter if we resend the kr, the RDE will cope. */ 378 kr->flags |= F_REDISTRIBUTED; 379 main_imsg_compose_rde(type, 0, kr, sizeof(struct kroute)); 380 } 381 382 /* rb-tree compare */ 383 int 384 kroute_compare(struct kroute_node *a, struct kroute_node *b) 385 { 386 if (ntohl(a->r.prefix.s_addr) < ntohl(b->r.prefix.s_addr)) 387 return (-1); 388 if (ntohl(a->r.prefix.s_addr) > ntohl(b->r.prefix.s_addr)) 389 return (1); 390 if (ntohl(a->r.netmask.s_addr) < ntohl(b->r.netmask.s_addr)) 391 return (-1); 392 if (ntohl(a->r.netmask.s_addr) > ntohl(b->r.netmask.s_addr)) 393 return (1); 394 395 /* if the priority is RTP_ANY finish on the first address hit */ 396 if (a->r.priority == RTP_ANY || b->r.priority == RTP_ANY) 397 return (0); 398 if (a->r.priority < b->r.priority) 399 return (-1); 400 if (a->r.priority > b->r.priority) 401 return (1); 402 403 return (0); 404 } 405 406 int 407 kif_compare(struct kif_node *a, struct kif_node *b) 408 { 409 return (b->k.ifindex - a->k.ifindex); 410 } 411 412 /* tree management */ 413 struct kroute_node * 414 kroute_find(in_addr_t prefix, in_addr_t netmask, u_int8_t prio) 415 { 416 struct kroute_node s, *kn, *tmp; 417 418 s.r.prefix.s_addr = prefix; 419 s.r.netmask.s_addr = netmask; 420 s.r.priority = prio; 421 422 kn = RB_FIND(kroute_tree, &krt, &s); 423 if (kn && prio == RTP_ANY) { 424 tmp = RB_PREV(kroute_tree, &krt, kn); 425 while (tmp) { 426 if (kroute_compare(&s, tmp) == 0) 427 kn = tmp; 428 else 429 break; 430 tmp = RB_PREV(kroute_tree, &krt, kn); 431 } 432 } 433 434 return (kn); 435 } 436 437 int 438 kroute_insert(struct kroute_node *kr) 439 { 440 if (RB_INSERT(kroute_tree, &krt, kr) != NULL) { 441 log_warnx("kroute_insert failed for %s/%u", 442 inet_ntoa(kr->r.prefix), 443 mask2prefixlen(kr->r.netmask.s_addr)); 444 free(kr); 445 return (-1); 446 } 447 448 if (!(kr->r.flags & F_KERNEL)) { 449 /* don't validate or redistribute rip route */ 450 kr->r.flags &= ~F_DOWN; 451 return (0); 452 } 453 454 if (kif_validate(kr->r.ifindex)) 455 kr->r.flags &= ~F_DOWN; 456 else 457 kr->r.flags |= F_DOWN; 458 459 kr_redistribute(IMSG_NETWORK_ADD, &kr->r); 460 461 return (0); 462 } 463 464 int 465 kroute_remove(struct kroute_node *kr) 466 { 467 if (RB_REMOVE(kroute_tree, &krt, kr) == NULL) { 468 log_warnx("kroute_remove failed for %s/%u", 469 inet_ntoa(kr->r.prefix), 470 mask2prefixlen(kr->r.netmask.s_addr)); 471 return (-1); 472 } 473 474 kr_redistribute(IMSG_NETWORK_DEL, &kr->r); 475 rtlabel_unref(kr->r.rtlabel); 476 477 free(kr); 478 return (0); 479 } 480 481 void 482 kroute_clear(void) 483 { 484 struct kroute_node *kr; 485 486 while ((kr = RB_MIN(kroute_tree, &krt)) != NULL) 487 kroute_remove(kr); 488 } 489 490 struct kif_node * 491 kif_find(int ifindex) 492 { 493 struct kif_node s; 494 495 bzero(&s, sizeof(s)); 496 s.k.ifindex = ifindex; 497 498 return (RB_FIND(kif_tree, &kit, &s)); 499 } 500 501 struct kif * 502 kif_findname(char *ifname) 503 { 504 struct kif_node *kif; 505 506 RB_FOREACH(kif, kif_tree, &kit) 507 if (!strcmp(ifname, kif->k.ifname)) 508 return (&kif->k); 509 510 return (NULL); 511 } 512 513 int 514 kif_insert(struct kif_node *kif) 515 { 516 if (RB_INSERT(kif_tree, &kit, kif) != NULL) { 517 log_warnx("RB_INSERT(kif_tree, &kit, kif)"); 518 free(kif); 519 return (-1); 520 } 521 522 return (0); 523 } 524 525 int 526 kif_remove(struct kif_node *kif) 527 { 528 if (RB_REMOVE(kif_tree, &kit, kif) == NULL) { 529 log_warnx("RB_REMOVE(kif_tree, &kit, kif)"); 530 return (-1); 531 } 532 533 free(kif); 534 return (0); 535 } 536 537 void 538 kif_clear(void) 539 { 540 struct kif_node *kif; 541 542 while ((kif = RB_MIN(kif_tree, &kit)) != NULL) 543 kif_remove(kif); 544 } 545 546 int 547 kif_validate(int ifindex) 548 { 549 struct kif_node *kif; 550 551 if ((kif = kif_find(ifindex)) == NULL) { 552 log_warnx("interface with index %u not found", ifindex); 553 return (1); 554 } 555 556 return (kif->k.nh_reachable); 557 } 558 559 struct kroute_node * 560 kroute_match(in_addr_t key) 561 { 562 u_int8_t i; 563 struct kroute_node *kr; 564 565 /* we will never match the default route */ 566 for (i = 32; i > 0; i--) 567 if ((kr = kroute_find(key & prefixlen2mask(i), 568 prefixlen2mask(i), RTP_ANY)) != NULL) 569 return (kr); 570 571 /* if we don't have a match yet, try to find a default route */ 572 if ((kr = kroute_find(0, 0, RTP_ANY)) != NULL) 573 return (kr); 574 575 return (NULL); 576 } 577 578 /* misc */ 579 int 580 protect_lo(void) 581 { 582 struct kroute_node *kr; 583 584 /* special protection for 127/8 */ 585 if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL) { 586 log_warn("protect_lo"); 587 return (-1); 588 } 589 kr->r.prefix.s_addr = htonl(INADDR_LOOPBACK); 590 kr->r.netmask.s_addr = htonl(IN_CLASSA_NET); 591 kr->r.flags = F_KERNEL|F_CONNECTED; 592 593 if (RB_INSERT(kroute_tree, &krt, kr) != NULL) 594 free(kr); /* kernel route already there, no problem */ 595 596 return (0); 597 } 598 599 u_int8_t 600 prefixlen_classful(in_addr_t ina) 601 { 602 /* it hurt to write this. */ 603 604 if (ina >= 0xf0000000U) /* class E */ 605 return (32); 606 else if (ina >= 0xe0000000U) /* class D */ 607 return (4); 608 else if (ina >= 0xc0000000U) /* class C */ 609 return (24); 610 else if (ina >= 0x80000000U) /* class B */ 611 return (16); 612 else /* class A */ 613 return (8); 614 } 615 616 u_int8_t 617 mask2prefixlen(in_addr_t ina) 618 { 619 if (ina == 0) 620 return (0); 621 else 622 return (33 - ffs(ntohl(ina))); 623 } 624 625 in_addr_t 626 prefixlen2mask(u_int8_t prefixlen) 627 { 628 if (prefixlen == 0) 629 return (0); 630 631 return (htonl(0xffffffff << (32 - prefixlen))); 632 } 633 634 #define ROUNDUP(a) \ 635 ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long)) 636 637 void 638 get_rtaddrs(int addrs, struct sockaddr *sa, struct sockaddr **rti_info) 639 { 640 int i; 641 642 for (i = 0; i < RTAX_MAX; i++) { 643 if (addrs & (1 << i)) { 644 rti_info[i] = sa; 645 sa = (struct sockaddr *)((char *)(sa) + 646 ROUNDUP(sa->sa_len)); 647 } else 648 rti_info[i] = NULL; 649 } 650 } 651 652 void 653 if_change(u_short ifindex, int flags, struct if_data *ifd) 654 { 655 struct kif_node *kif; 656 struct kroute_node *kr; 657 int type; 658 u_int8_t reachable; 659 660 if ((kif = kif_find(ifindex)) == NULL) { 661 log_warnx("interface with index %u not found", ifindex); 662 return; 663 } 664 665 kif->k.flags = flags; 666 kif->k.link_state = ifd->ifi_link_state; 667 kif->k.if_type = ifd->ifi_type; 668 kif->k.baudrate = ifd->ifi_baudrate; 669 670 if ((reachable = (flags & IFF_UP) && 671 LINK_STATE_IS_UP(ifd->ifi_link_state)) == kif->k.nh_reachable) 672 return; /* nothing changed wrt nexthop validity */ 673 674 kif->k.nh_reachable = reachable; 675 type = reachable ? IMSG_NETWORK_ADD : IMSG_NETWORK_DEL; 676 677 /* notify ripe about interface link state */ 678 main_imsg_compose_ripe(IMSG_IFINFO, 0, &kif->k, sizeof(kif->k)); 679 680 /* update redistribute list */ 681 RB_FOREACH(kr, kroute_tree, &krt) 682 if (kr->r.ifindex == ifindex) { 683 if (reachable) 684 kr->r.flags &= ~F_DOWN; 685 else 686 kr->r.flags |= F_DOWN; 687 688 kr_redistribute(type, &kr->r); 689 } 690 } 691 692 void 693 if_announce(void *msg) 694 { 695 struct if_announcemsghdr *ifan; 696 struct kif_node *kif; 697 698 ifan = msg; 699 700 switch (ifan->ifan_what) { 701 case IFAN_ARRIVAL: 702 if ((kif = calloc(1, sizeof(struct kif_node))) == NULL) { 703 log_warn("if_announce"); 704 return; 705 } 706 707 kif->k.ifindex = ifan->ifan_index; 708 strlcpy(kif->k.ifname, ifan->ifan_name, sizeof(kif->k.ifname)); 709 kif_insert(kif); 710 break; 711 case IFAN_DEPARTURE: 712 kif = kif_find(ifan->ifan_index); 713 if (kif != NULL) 714 kif_remove(kif); 715 break; 716 } 717 } 718 719 /* rtsock */ 720 int 721 send_rtmsg(int fd, int action, struct kroute *kroute) 722 { 723 struct iovec iov[4]; 724 struct rt_msghdr hdr; 725 struct sockaddr_in prefix; 726 struct sockaddr_in nexthop; 727 struct sockaddr_in mask; 728 int iovcnt = 0; 729 730 if (kr_state.fib_sync == 0) 731 return (0); 732 733 /* initialize header */ 734 bzero(&hdr, sizeof(hdr)); 735 hdr.rtm_version = RTM_VERSION; 736 hdr.rtm_type = action; 737 hdr.rtm_priority = kr_state.fib_prio; 738 hdr.rtm_tableid = kr_state.rdomain; 739 if (action == RTM_CHANGE) 740 hdr.rtm_fmask = RTF_REJECT|RTF_BLACKHOLE; 741 hdr.rtm_seq = kr_state.rtseq++; /* overflow doesn't matter */ 742 hdr.rtm_msglen = sizeof(hdr); 743 /* adjust iovec */ 744 iov[iovcnt].iov_base = &hdr; 745 iov[iovcnt++].iov_len = sizeof(hdr); 746 747 bzero(&prefix, sizeof(prefix)); 748 prefix.sin_len = sizeof(prefix); 749 prefix.sin_family = AF_INET; 750 prefix.sin_addr.s_addr = kroute->prefix.s_addr; 751 /* adjust header */ 752 hdr.rtm_addrs |= RTA_DST; 753 hdr.rtm_msglen += sizeof(prefix); 754 /* adjust iovec */ 755 iov[iovcnt].iov_base = &prefix; 756 iov[iovcnt++].iov_len = sizeof(prefix); 757 758 if (kroute->nexthop.s_addr != 0) { 759 bzero(&nexthop, sizeof(nexthop)); 760 nexthop.sin_len = sizeof(nexthop); 761 nexthop.sin_family = AF_INET; 762 nexthop.sin_addr.s_addr = kroute->nexthop.s_addr; 763 /* adjust header */ 764 hdr.rtm_flags |= RTF_GATEWAY; 765 hdr.rtm_addrs |= RTA_GATEWAY; 766 hdr.rtm_msglen += sizeof(nexthop); 767 /* adjust iovec */ 768 iov[iovcnt].iov_base = &nexthop; 769 iov[iovcnt++].iov_len = sizeof(nexthop); 770 } 771 772 bzero(&mask, sizeof(mask)); 773 mask.sin_len = sizeof(mask); 774 mask.sin_family = AF_INET; 775 mask.sin_addr.s_addr = kroute->netmask.s_addr; 776 /* adjust header */ 777 hdr.rtm_addrs |= RTA_NETMASK; 778 hdr.rtm_msglen += sizeof(mask); 779 /* adjust iovec */ 780 iov[iovcnt].iov_base = &mask; 781 iov[iovcnt++].iov_len = sizeof(mask); 782 783 784 retry: 785 if (writev(fd, iov, iovcnt) == -1) { 786 if (errno == ESRCH) { 787 if (hdr.rtm_type == RTM_CHANGE) { 788 hdr.rtm_type = RTM_ADD; 789 goto retry; 790 } else if (hdr.rtm_type == RTM_DELETE) { 791 log_info("route %s/%u vanished before delete", 792 inet_ntoa(kroute->prefix), 793 mask2prefixlen(kroute->netmask.s_addr)); 794 return (0); 795 } 796 } 797 log_warn("send_rtmsg: action %u, prefix %s/%u", 798 hdr.rtm_type, inet_ntoa(kroute->prefix), 799 mask2prefixlen(kroute->netmask.s_addr)); 800 return (0); 801 } 802 803 return (0); 804 } 805 806 int 807 fetchtable(void) 808 { 809 size_t len; 810 int mib[7]; 811 char *buf, *next, *lim; 812 struct rt_msghdr *rtm; 813 struct sockaddr *sa, *rti_info[RTAX_MAX]; 814 struct sockaddr_in *sa_in; 815 struct sockaddr_rtlabel *label; 816 struct kroute_node *kr; 817 struct iface *iface = NULL; 818 819 mib[0] = CTL_NET; 820 mib[1] = PF_ROUTE; 821 mib[2] = 0; 822 mib[3] = AF_INET; 823 mib[4] = NET_RT_DUMP; 824 mib[5] = 0; 825 mib[6] = kr_state.rdomain; /* rtableid */ 826 827 if (sysctl(mib, 7, NULL, &len, NULL, 0) == -1) { 828 log_warn("sysctl"); 829 return (-1); 830 } 831 if ((buf = malloc(len)) == NULL) { 832 log_warn("fetchtable"); 833 return (-1); 834 } 835 if (sysctl(mib, 7, buf, &len, NULL, 0) == -1) { 836 log_warn("sysctl"); 837 free(buf); 838 return (-1); 839 } 840 841 lim = buf + len; 842 for (next = buf; next < lim; next += rtm->rtm_msglen) { 843 rtm = (struct rt_msghdr *)next; 844 if (rtm->rtm_version != RTM_VERSION) 845 continue; 846 sa = (struct sockaddr *)(next + rtm->rtm_hdrlen); 847 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 848 849 if ((sa = rti_info[RTAX_DST]) == NULL) 850 continue; 851 852 /* Skip ARP/ND cache and broadcast routes. */ 853 if (rtm->rtm_flags & (RTF_LLINFO|RTF_BROADCAST)) 854 continue; 855 856 #ifdef RTF_MPATH 857 if (rtm->rtm_flags & RTF_MPATH) /* multipath */ 858 continue; 859 #endif 860 861 if ((kr = calloc(1, sizeof(struct kroute_node))) == NULL) { 862 log_warn("fetchtable"); 863 free(buf); 864 return (-1); 865 } 866 867 kr->r.flags = F_KERNEL; 868 kr->r.priority = rtm->rtm_priority; 869 870 switch (sa->sa_family) { 871 case AF_INET: 872 kr->r.prefix.s_addr = 873 ((struct sockaddr_in *)sa)->sin_addr.s_addr; 874 sa_in = (struct sockaddr_in *)rti_info[RTAX_NETMASK]; 875 if (rtm->rtm_flags & RTF_STATIC) 876 kr->r.flags |= F_STATIC; 877 if (rtm->rtm_flags & RTF_BLACKHOLE) 878 kr->r.flags |= F_BLACKHOLE; 879 if (rtm->rtm_flags & RTF_REJECT) 880 kr->r.flags |= F_REJECT; 881 if (rtm->rtm_flags & RTF_DYNAMIC) 882 kr->r.flags |= F_DYNAMIC; 883 if (sa_in != NULL) { 884 if (sa_in->sin_len == 0) 885 break; 886 kr->r.netmask.s_addr = 887 sa_in->sin_addr.s_addr; 888 } else if (rtm->rtm_flags & RTF_HOST) 889 kr->r.netmask.s_addr = prefixlen2mask(32); 890 else 891 kr->r.netmask.s_addr = 892 prefixlen2mask(prefixlen_classful 893 (kr->r.prefix.s_addr)); 894 break; 895 default: 896 free(kr); 897 continue; 898 } 899 900 kr->r.ifindex = rtm->rtm_index; 901 902 iface = if_find_index(rtm->rtm_index); 903 if (iface != NULL) 904 kr->r.metric = iface->cost; 905 else 906 kr->r.metric = DEFAULT_COST; 907 908 if ((sa = rti_info[RTAX_GATEWAY]) != NULL) 909 switch (sa->sa_family) { 910 case AF_INET: 911 if (rtm->rtm_flags & RTF_CONNECTED) { 912 kr->r.flags |= F_CONNECTED; 913 break; 914 } 915 916 kr->r.nexthop.s_addr = 917 ((struct sockaddr_in *)sa)->sin_addr.s_addr; 918 break; 919 case AF_LINK: 920 /* 921 * Traditional BSD connected routes have 922 * a gateway of type AF_LINK. 923 */ 924 kr->r.flags |= F_CONNECTED; 925 break; 926 } 927 928 if (rtm->rtm_priority == kr_state.fib_prio) { 929 send_rtmsg(kr_state.fd, RTM_DELETE, &kr->r); 930 free(kr); 931 } else { 932 if ((label = (struct sockaddr_rtlabel *) 933 rti_info[RTAX_LABEL]) != NULL) 934 kr->r.rtlabel = 935 rtlabel_name2id(label->sr_label); 936 kroute_insert(kr); 937 } 938 939 } 940 free(buf); 941 return (0); 942 } 943 944 int 945 fetchifs(int ifindex) 946 { 947 size_t len; 948 int mib[6]; 949 char *buf, *next, *lim; 950 struct if_msghdr ifm; 951 struct kif_node *kif; 952 struct sockaddr *sa, *rti_info[RTAX_MAX]; 953 struct sockaddr_dl *sdl; 954 955 mib[0] = CTL_NET; 956 mib[1] = PF_ROUTE; 957 mib[2] = 0; 958 mib[3] = AF_INET; 959 mib[4] = NET_RT_IFLIST; 960 mib[5] = ifindex; 961 962 if (sysctl(mib, 6, NULL, &len, NULL, 0) == -1) { 963 log_warn("sysctl"); 964 return (-1); 965 } 966 if ((buf = malloc(len)) == NULL) { 967 log_warn("fetchif"); 968 return (-1); 969 } 970 if (sysctl(mib, 6, buf, &len, NULL, 0) == -1) { 971 log_warn("sysctl"); 972 free(buf); 973 return (-1); 974 } 975 976 lim = buf + len; 977 for (next = buf; next < lim; next += ifm.ifm_msglen) { 978 memcpy(&ifm, next, sizeof(ifm)); 979 if (ifm.ifm_version != RTM_VERSION) 980 continue; 981 if (ifm.ifm_type != RTM_IFINFO) 982 continue; 983 984 sa = (struct sockaddr *)(next + sizeof(ifm)); 985 get_rtaddrs(ifm.ifm_addrs, sa, rti_info); 986 987 if ((kif = calloc(1, sizeof(struct kif_node))) == NULL) { 988 log_warn("fetchifs"); 989 free(buf); 990 return (-1); 991 } 992 993 kif->k.ifindex = ifm.ifm_index; 994 kif->k.flags = ifm.ifm_flags; 995 kif->k.link_state = ifm.ifm_data.ifi_link_state; 996 kif->k.if_type = ifm.ifm_data.ifi_type; 997 kif->k.baudrate = ifm.ifm_data.ifi_baudrate; 998 kif->k.mtu = ifm.ifm_data.ifi_mtu; 999 kif->k.nh_reachable = (kif->k.flags & IFF_UP) && 1000 LINK_STATE_IS_UP(ifm.ifm_data.ifi_link_state); 1001 if ((sa = rti_info[RTAX_IFP]) != NULL) 1002 if (sa->sa_family == AF_LINK) { 1003 sdl = (struct sockaddr_dl *)sa; 1004 if (sdl->sdl_nlen >= sizeof(kif->k.ifname)) 1005 memcpy(kif->k.ifname, sdl->sdl_data, 1006 sizeof(kif->k.ifname) - 1); 1007 else if (sdl->sdl_nlen > 0) 1008 memcpy(kif->k.ifname, sdl->sdl_data, 1009 sdl->sdl_nlen); 1010 /* string already terminated via calloc() */ 1011 } 1012 1013 kif_insert(kif); 1014 } 1015 free(buf); 1016 return (0); 1017 } 1018 1019 int 1020 dispatch_rtmsg(void) 1021 { 1022 char buf[RT_BUF_SIZE]; 1023 ssize_t n; 1024 char *next, *lim; 1025 struct rt_msghdr *rtm; 1026 struct if_msghdr ifm; 1027 struct sockaddr *sa, *rti_info[RTAX_MAX]; 1028 struct sockaddr_in *sa_in; 1029 struct sockaddr_rtlabel *label; 1030 struct kroute_node *kr; 1031 struct in_addr prefix, nexthop, netmask; 1032 struct iface *iface = NULL; 1033 int flags; 1034 u_short ifindex = 0; 1035 u_int8_t metric, prio; 1036 1037 if ((n = read(kr_state.fd, &buf, sizeof(buf))) == -1) { 1038 if (errno == EAGAIN || errno == EINTR) 1039 return (0); 1040 log_warn("dispatch_rtmsg: read error"); 1041 return (-1); 1042 } 1043 1044 if (n == 0) { 1045 log_warnx("routing socket closed"); 1046 return (-1); 1047 } 1048 1049 lim = buf + n; 1050 for (next = buf; next < lim; next += rtm->rtm_msglen) { 1051 rtm = (struct rt_msghdr *)next; 1052 if (lim < next + sizeof(u_short) || 1053 lim < next + rtm->rtm_msglen) 1054 fatalx("dispatch_rtmsg: partial rtm in buffer"); 1055 if (rtm->rtm_version != RTM_VERSION) 1056 continue; 1057 1058 prefix.s_addr = 0; 1059 netmask.s_addr = 0; 1060 flags = F_KERNEL; 1061 nexthop.s_addr = 0; 1062 prio = 0; 1063 1064 if (rtm->rtm_type == RTM_ADD || rtm->rtm_type == RTM_CHANGE || 1065 rtm->rtm_type == RTM_DELETE) { 1066 sa = (struct sockaddr *)(next + rtm->rtm_hdrlen); 1067 get_rtaddrs(rtm->rtm_addrs, sa, rti_info); 1068 1069 if (rtm->rtm_tableid != kr_state.rdomain) 1070 continue; 1071 1072 if (rtm->rtm_pid == kr_state.pid) /* cause by us */ 1073 continue; 1074 1075 if (rtm->rtm_errno) /* failed attempts... */ 1076 continue; 1077 1078 /* Skip ARP/ND cache and broadcast routes. */ 1079 if (rtm->rtm_flags & (RTF_LLINFO|RTF_BROADCAST)) 1080 continue; 1081 1082 prio = rtm->rtm_priority; 1083 1084 switch (sa->sa_family) { 1085 case AF_INET: 1086 prefix.s_addr = 1087 ((struct sockaddr_in *)sa)->sin_addr.s_addr; 1088 sa_in = (struct sockaddr_in *) 1089 rti_info[RTAX_NETMASK]; 1090 if (sa_in != NULL) { 1091 if (sa_in->sin_len != 0) 1092 netmask.s_addr = 1093 sa_in->sin_addr.s_addr; 1094 } else if (rtm->rtm_flags & RTF_HOST) 1095 netmask.s_addr = prefixlen2mask(32); 1096 else 1097 netmask.s_addr = 1098 prefixlen2mask(prefixlen_classful( 1099 prefix.s_addr)); 1100 if (rtm->rtm_flags & RTF_STATIC) 1101 flags |= F_STATIC; 1102 if (rtm->rtm_flags & RTF_BLACKHOLE) 1103 flags |= F_BLACKHOLE; 1104 if (rtm->rtm_flags & RTF_REJECT) 1105 flags |= F_REJECT; 1106 if (rtm->rtm_flags & RTF_DYNAMIC) 1107 flags |= F_DYNAMIC; 1108 break; 1109 default: 1110 continue; 1111 } 1112 1113 ifindex = rtm->rtm_index; 1114 if ((sa = rti_info[RTAX_GATEWAY]) != NULL) { 1115 switch (sa->sa_family) { 1116 case AF_INET: 1117 nexthop.s_addr = ((struct 1118 sockaddr_in *)sa)->sin_addr.s_addr; 1119 break; 1120 case AF_LINK: 1121 flags |= F_CONNECTED; 1122 break; 1123 } 1124 } 1125 } 1126 1127 switch (rtm->rtm_type) { 1128 case RTM_ADD: 1129 case RTM_CHANGE: 1130 if (nexthop.s_addr == 0 && !(flags & F_CONNECTED)) { 1131 log_warnx("dispatch_rtmsg no nexthop for %s/%u", 1132 inet_ntoa(prefix), 1133 mask2prefixlen(netmask.s_addr)); 1134 continue; 1135 } 1136 1137 if ((kr = kroute_find(prefix.s_addr, netmask.s_addr, 1138 prio)) != NULL) { 1139 if (kr->r.flags & F_REDISTRIBUTED) 1140 flags |= F_REDISTRIBUTED; 1141 kr->r.nexthop.s_addr = nexthop.s_addr; 1142 kr->r.flags = flags; 1143 kr->r.ifindex = ifindex; 1144 kr->r.priority = prio; 1145 1146 rtlabel_unref(kr->r.rtlabel); 1147 kr->r.rtlabel = 0; 1148 if ((label = (struct sockaddr_rtlabel *) 1149 rti_info[RTAX_LABEL]) != NULL) 1150 kr->r.rtlabel = 1151 rtlabel_name2id(label->sr_label); 1152 1153 if (kif_validate(kr->r.ifindex)) 1154 kr->r.flags &= ~F_DOWN; 1155 else 1156 kr->r.flags |= F_DOWN; 1157 1158 /* just readd, the RDE will care */ 1159 kr_redistribute(IMSG_NETWORK_ADD, &kr->r); 1160 } else { 1161 if ((kr = calloc(1, 1162 sizeof(struct kroute_node))) == NULL) { 1163 log_warn("dispatch_rtmsg"); 1164 return (-1); 1165 } 1166 1167 iface = if_find_index(rtm->rtm_index); 1168 if (iface != NULL) 1169 metric = iface->cost; 1170 else 1171 metric = DEFAULT_COST; 1172 1173 kr->r.prefix.s_addr = prefix.s_addr; 1174 kr->r.netmask.s_addr = netmask.s_addr; 1175 kr->r.nexthop.s_addr = nexthop.s_addr; 1176 kr->r.metric = metric; 1177 kr->r.flags = flags; 1178 kr->r.ifindex = ifindex; 1179 1180 if ((label = (struct sockaddr_rtlabel *) 1181 rti_info[RTAX_LABEL]) != NULL) 1182 kr->r.rtlabel = 1183 rtlabel_name2id(label->sr_label); 1184 1185 kroute_insert(kr); 1186 } 1187 break; 1188 case RTM_DELETE: 1189 if ((kr = kroute_find(prefix.s_addr, netmask.s_addr, 1190 prio)) == NULL) 1191 continue; 1192 if (!(kr->r.flags & F_KERNEL)) 1193 continue; 1194 if (kroute_remove(kr) == -1) 1195 return (-1); 1196 break; 1197 case RTM_IFINFO: 1198 memcpy(&ifm, next, sizeof(ifm)); 1199 if_change(ifm.ifm_index, ifm.ifm_flags, 1200 &ifm.ifm_data); 1201 break; 1202 case RTM_IFANNOUNCE: 1203 if_announce(next); 1204 break; 1205 default: 1206 /* ignore for now */ 1207 break; 1208 } 1209 } 1210 return (0); 1211 } 1212