1 /*- 2 * Copyright (c) 1980, 1986, 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 * @(#)if.c 8.5 (Berkeley) 1/9/95 30 * $FreeBSD$ 31 */ 32 33 #include "opt_compat.h" 34 #include "opt_inet6.h" 35 #include "opt_inet.h" 36 #include "opt_mac.h" 37 38 #include <sys/param.h> 39 #include <sys/types.h> 40 #include <sys/conf.h> 41 #include <sys/mac.h> 42 #include <sys/malloc.h> 43 #include <sys/sbuf.h> 44 #include <sys/bus.h> 45 #include <sys/mbuf.h> 46 #include <sys/systm.h> 47 #include <sys/proc.h> 48 #include <sys/socket.h> 49 #include <sys/socketvar.h> 50 #include <sys/protosw.h> 51 #include <sys/kernel.h> 52 #include <sys/sockio.h> 53 #include <sys/syslog.h> 54 #include <sys/sysctl.h> 55 #include <sys/taskqueue.h> 56 #include <sys/domain.h> 57 #include <sys/jail.h> 58 #include <machine/stdarg.h> 59 60 #include <net/if.h> 61 #include <net/if_arp.h> 62 #include <net/if_clone.h> 63 #include <net/if_dl.h> 64 #include <net/if_types.h> 65 #include <net/if_var.h> 66 #include <net/radix.h> 67 #include <net/route.h> 68 69 #if defined(INET) || defined(INET6) 70 /*XXX*/ 71 #include <netinet/in.h> 72 #include <netinet/in_var.h> 73 #ifdef INET6 74 #include <netinet6/in6_var.h> 75 #include <netinet6/in6_ifattach.h> 76 #endif 77 #endif 78 #ifdef INET 79 #include <netinet/if_ether.h> 80 #endif 81 82 void (*ng_ether_link_state_p)(struct ifnet *ifp, int state); 83 84 struct mbuf *(*tbr_dequeue_ptr)(struct ifaltq *, int) = NULL; 85 86 static void if_attachdomain(void *); 87 static void if_attachdomain1(struct ifnet *); 88 static int ifconf(u_long, caddr_t); 89 static void if_grow(void); 90 static void if_init(void *); 91 static void if_check(void *); 92 static int if_findindex(struct ifnet *); 93 static void if_qflush(struct ifaltq *); 94 static void if_route(struct ifnet *, int flag, int fam); 95 static void if_slowtimo(void *); 96 static void if_unroute(struct ifnet *, int flag, int fam); 97 static void link_rtrequest(int, struct rtentry *, struct rt_addrinfo *); 98 static int if_rtdel(struct radix_node *, void *); 99 static int ifhwioctl(u_long, struct ifnet *, caddr_t, struct thread *); 100 static void if_start_deferred(void *context, int pending); 101 #ifdef INET6 102 /* 103 * XXX: declare here to avoid to include many inet6 related files.. 104 * should be more generalized? 105 */ 106 extern void nd6_setmtu(struct ifnet *); 107 #endif 108 109 int if_index = 0; 110 struct ifindex_entry *ifindex_table = NULL; 111 int ifqmaxlen = IFQ_MAXLEN; 112 struct ifnethead ifnet; /* depend on static init XXX */ 113 struct mtx ifnet_lock; 114 115 static int if_indexlim = 8; 116 static struct knlist ifklist; 117 118 static void filt_netdetach(struct knote *kn); 119 static int filt_netdev(struct knote *kn, long hint); 120 121 static struct filterops netdev_filtops = 122 { 1, NULL, filt_netdetach, filt_netdev }; 123 124 /* 125 * System initialization 126 */ 127 SYSINIT(interfaces, SI_SUB_INIT_IF, SI_ORDER_FIRST, if_init, NULL) 128 SYSINIT(interface_check, SI_SUB_PROTO_IF, SI_ORDER_FIRST, if_check, NULL) 129 130 MALLOC_DEFINE(M_IFADDR, "ifaddr", "interface address"); 131 MALLOC_DEFINE(M_IFMADDR, "ether_multi", "link-level multicast address"); 132 133 static d_open_t netopen; 134 static d_close_t netclose; 135 static d_ioctl_t netioctl; 136 static d_kqfilter_t netkqfilter; 137 138 static struct cdevsw net_cdevsw = { 139 .d_version = D_VERSION, 140 .d_flags = D_NEEDGIANT, 141 .d_open = netopen, 142 .d_close = netclose, 143 .d_ioctl = netioctl, 144 .d_name = "net", 145 .d_kqfilter = netkqfilter, 146 }; 147 148 static int 149 netopen(struct cdev *dev, int flag, int mode, struct thread *td) 150 { 151 return (0); 152 } 153 154 static int 155 netclose(struct cdev *dev, int flags, int fmt, struct thread *td) 156 { 157 return (0); 158 } 159 160 static int 161 netioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td) 162 { 163 struct ifnet *ifp; 164 int error, idx; 165 166 /* only support interface specific ioctls */ 167 if (IOCGROUP(cmd) != 'i') 168 return (EOPNOTSUPP); 169 idx = minor(dev); 170 if (idx == 0) { 171 /* 172 * special network device, not interface. 173 */ 174 if (cmd == SIOCGIFCONF) 175 return (ifconf(cmd, data)); /* XXX remove cmd */ 176 return (EOPNOTSUPP); 177 } 178 179 ifp = ifnet_byindex(idx); 180 if (ifp == NULL) 181 return (ENXIO); 182 183 error = ifhwioctl(cmd, ifp, data, td); 184 if (error == ENOIOCTL) 185 error = EOPNOTSUPP; 186 return (error); 187 } 188 189 static int 190 netkqfilter(struct cdev *dev, struct knote *kn) 191 { 192 struct knlist *klist; 193 struct ifnet *ifp; 194 int idx; 195 196 switch (kn->kn_filter) { 197 case EVFILT_NETDEV: 198 kn->kn_fop = &netdev_filtops; 199 break; 200 default: 201 return (1); 202 } 203 204 idx = minor(dev); 205 if (idx == 0) { 206 klist = &ifklist; 207 } else { 208 ifp = ifnet_byindex(idx); 209 if (ifp == NULL) 210 return (1); 211 klist = &ifp->if_klist; 212 } 213 214 kn->kn_hook = (caddr_t)klist; 215 216 knlist_add(klist, kn, 0); 217 218 return (0); 219 } 220 221 static void 222 filt_netdetach(struct knote *kn) 223 { 224 struct knlist *klist = (struct knlist *)kn->kn_hook; 225 226 knlist_remove(klist, kn, 0); 227 } 228 229 static int 230 filt_netdev(struct knote *kn, long hint) 231 { 232 struct knlist *klist = (struct knlist *)kn->kn_hook; 233 234 /* 235 * Currently NOTE_EXIT is abused to indicate device detach. 236 */ 237 if (hint == NOTE_EXIT) { 238 kn->kn_data = NOTE_LINKINV; 239 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 240 knlist_remove_inevent(klist, kn); 241 return (1); 242 } 243 if (hint != 0) 244 kn->kn_data = hint; /* current status */ 245 if (kn->kn_sfflags & hint) 246 kn->kn_fflags |= hint; 247 return (kn->kn_fflags != 0); 248 } 249 250 /* 251 * Network interface utility routines. 252 * 253 * Routines with ifa_ifwith* names take sockaddr *'s as 254 * parameters. 255 */ 256 /* ARGSUSED*/ 257 static void 258 if_init(void *dummy __unused) 259 { 260 261 IFNET_LOCK_INIT(); 262 TAILQ_INIT(&ifnet); 263 knlist_init(&ifklist, NULL); 264 if_grow(); /* create initial table */ 265 ifdev_byindex(0) = make_dev(&net_cdevsw, 0, 266 UID_ROOT, GID_WHEEL, 0600, "network"); 267 if_clone_init(); 268 } 269 270 static void 271 if_grow(void) 272 { 273 u_int n; 274 struct ifindex_entry *e; 275 276 if_indexlim <<= 1; 277 n = if_indexlim * sizeof(*e); 278 e = malloc(n, M_IFADDR, M_WAITOK | M_ZERO); 279 if (ifindex_table != NULL) { 280 memcpy((caddr_t)e, (caddr_t)ifindex_table, n/2); 281 free((caddr_t)ifindex_table, M_IFADDR); 282 } 283 ifindex_table = e; 284 } 285 286 /* ARGSUSED*/ 287 static void 288 if_check(void *dummy __unused) 289 { 290 struct ifnet *ifp; 291 int s; 292 293 s = splimp(); 294 IFNET_RLOCK(); /* could sleep on rare error; mostly okay XXX */ 295 TAILQ_FOREACH(ifp, &ifnet, if_link) { 296 if (ifp->if_snd.ifq_maxlen == 0) { 297 if_printf(ifp, "XXX: driver didn't set ifq_maxlen\n"); 298 ifp->if_snd.ifq_maxlen = ifqmaxlen; 299 } 300 if (!mtx_initialized(&ifp->if_snd.ifq_mtx)) { 301 if_printf(ifp, 302 "XXX: driver didn't initialize queue mtx\n"); 303 mtx_init(&ifp->if_snd.ifq_mtx, "unknown", 304 MTX_NETWORK_LOCK, MTX_DEF); 305 } 306 } 307 IFNET_RUNLOCK(); 308 splx(s); 309 if_slowtimo(0); 310 } 311 312 static int 313 if_findindex(struct ifnet *ifp) 314 { 315 int i, unit; 316 char eaddr[18], devname[32]; 317 const char *name, *p; 318 319 switch (ifp->if_type) { 320 case IFT_ETHER: /* these types use struct arpcom */ 321 case IFT_FDDI: 322 case IFT_XETHER: 323 case IFT_ISO88025: 324 case IFT_L2VLAN: 325 snprintf(eaddr, 18, "%6D", IFP2AC(ifp)->ac_enaddr, ":"); 326 break; 327 default: 328 eaddr[0] = '\0'; 329 break; 330 } 331 strlcpy(devname, ifp->if_xname, sizeof(devname)); 332 name = net_cdevsw.d_name; 333 i = 0; 334 while ((resource_find_dev(&i, name, &unit, NULL, NULL)) == 0) { 335 if (resource_string_value(name, unit, "ether", &p) == 0) 336 if (strcmp(p, eaddr) == 0) 337 goto found; 338 if (resource_string_value(name, unit, "dev", &p) == 0) 339 if (strcmp(p, devname) == 0) 340 goto found; 341 } 342 unit = 0; 343 found: 344 if (unit != 0) { 345 if (ifaddr_byindex(unit) == NULL) 346 return (unit); 347 printf("%s%d in use, cannot hardwire it to %s.\n", 348 name, unit, devname); 349 } 350 for (unit = 1; ; unit++) { 351 if (unit <= if_index && ifaddr_byindex(unit) != NULL) 352 continue; 353 if (resource_string_value(name, unit, "ether", &p) == 0 || 354 resource_string_value(name, unit, "dev", &p) == 0) 355 continue; 356 break; 357 } 358 return (unit); 359 } 360 361 /* 362 * Attach an interface to the 363 * list of "active" interfaces. 364 */ 365 void 366 if_attach(struct ifnet *ifp) 367 { 368 unsigned socksize, ifasize; 369 int namelen, masklen; 370 struct sockaddr_dl *sdl; 371 struct ifaddr *ifa; 372 373 TASK_INIT(&ifp->if_starttask, 0, if_start_deferred, ifp); 374 IF_AFDATA_LOCK_INIT(ifp); 375 ifp->if_afdata_initialized = 0; 376 IFNET_WLOCK(); 377 TAILQ_INSERT_TAIL(&ifnet, ifp, if_link); 378 IFNET_WUNLOCK(); 379 /* 380 * XXX - 381 * The old code would work if the interface passed a pre-existing 382 * chain of ifaddrs to this code. We don't trust our callers to 383 * properly initialize the tailq, however, so we no longer allow 384 * this unlikely case. 385 */ 386 TAILQ_INIT(&ifp->if_addrhead); 387 TAILQ_INIT(&ifp->if_prefixhead); 388 TAILQ_INIT(&ifp->if_multiaddrs); 389 knlist_init(&ifp->if_klist, NULL); 390 getmicrotime(&ifp->if_lastchange); 391 ifp->if_data.ifi_epoch = time_second; 392 393 #ifdef MAC 394 mac_init_ifnet(ifp); 395 mac_create_ifnet(ifp); 396 #endif 397 398 ifp->if_index = if_findindex(ifp); 399 if (ifp->if_index > if_index) 400 if_index = ifp->if_index; 401 if (if_index >= if_indexlim) 402 if_grow(); 403 ifp->if_data.ifi_datalen = sizeof(struct if_data); 404 405 ifnet_byindex(ifp->if_index) = ifp; 406 ifdev_byindex(ifp->if_index) = make_dev(&net_cdevsw, 407 unit2minor(ifp->if_index), 408 UID_ROOT, GID_WHEEL, 0600, "%s/%s", 409 net_cdevsw.d_name, ifp->if_xname); 410 make_dev_alias(ifdev_byindex(ifp->if_index), "%s%d", 411 net_cdevsw.d_name, ifp->if_index); 412 413 mtx_init(&ifp->if_snd.ifq_mtx, ifp->if_xname, "if send queue", MTX_DEF); 414 415 /* 416 * create a Link Level name for this device 417 */ 418 namelen = strlen(ifp->if_xname); 419 /* 420 * Always save enough space for any possiable name so we can do 421 * a rename in place later. 422 */ 423 masklen = offsetof(struct sockaddr_dl, sdl_data[0]) + IFNAMSIZ; 424 socksize = masklen + ifp->if_addrlen; 425 if (socksize < sizeof(*sdl)) 426 socksize = sizeof(*sdl); 427 socksize = roundup2(socksize, sizeof(long)); 428 ifasize = sizeof(*ifa) + 2 * socksize; 429 ifa = malloc(ifasize, M_IFADDR, M_WAITOK | M_ZERO); 430 IFA_LOCK_INIT(ifa); 431 sdl = (struct sockaddr_dl *)(ifa + 1); 432 sdl->sdl_len = socksize; 433 sdl->sdl_family = AF_LINK; 434 bcopy(ifp->if_xname, sdl->sdl_data, namelen); 435 sdl->sdl_nlen = namelen; 436 sdl->sdl_index = ifp->if_index; 437 sdl->sdl_type = ifp->if_type; 438 ifaddr_byindex(ifp->if_index) = ifa; 439 ifa->ifa_ifp = ifp; 440 ifa->ifa_rtrequest = link_rtrequest; 441 ifa->ifa_addr = (struct sockaddr *)sdl; 442 sdl = (struct sockaddr_dl *)(socksize + (caddr_t)sdl); 443 ifa->ifa_netmask = (struct sockaddr *)sdl; 444 sdl->sdl_len = masklen; 445 while (namelen != 0) 446 sdl->sdl_data[--namelen] = 0xff; 447 ifa->ifa_refcnt = 1; 448 TAILQ_INSERT_HEAD(&ifp->if_addrhead, ifa, ifa_link); 449 ifp->if_broadcastaddr = NULL; /* reliably crash if used uninitialized */ 450 ifp->if_snd.altq_type = 0; 451 ifp->if_snd.altq_disc = NULL; 452 ifp->if_snd.altq_flags &= ALTQF_CANTCHANGE; 453 ifp->if_snd.altq_tbr = NULL; 454 ifp->if_snd.altq_ifp = ifp; 455 456 if (domain_init_status >= 2) 457 if_attachdomain1(ifp); 458 459 EVENTHANDLER_INVOKE(ifnet_arrival_event, ifp); 460 461 /* Announce the interface. */ 462 rt_ifannouncemsg(ifp, IFAN_ARRIVAL); 463 } 464 465 static void 466 if_attachdomain(void *dummy) 467 { 468 struct ifnet *ifp; 469 int s; 470 471 s = splnet(); 472 TAILQ_FOREACH(ifp, &ifnet, if_link) 473 if_attachdomain1(ifp); 474 splx(s); 475 } 476 SYSINIT(domainifattach, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_SECOND, 477 if_attachdomain, NULL); 478 479 static void 480 if_attachdomain1(struct ifnet *ifp) 481 { 482 struct domain *dp; 483 int s; 484 485 s = splnet(); 486 487 /* 488 * Since dp->dom_ifattach calls malloc() with M_WAITOK, we 489 * cannot lock ifp->if_afdata initialization, entirely. 490 */ 491 if (IF_AFDATA_TRYLOCK(ifp) == 0) { 492 splx(s); 493 return; 494 } 495 if (ifp->if_afdata_initialized >= domain_init_status) { 496 IF_AFDATA_UNLOCK(ifp); 497 splx(s); 498 printf("if_attachdomain called more than once on %s\n", 499 ifp->if_xname); 500 return; 501 } 502 ifp->if_afdata_initialized = domain_init_status; 503 IF_AFDATA_UNLOCK(ifp); 504 505 /* address family dependent data region */ 506 bzero(ifp->if_afdata, sizeof(ifp->if_afdata)); 507 for (dp = domains; dp; dp = dp->dom_next) { 508 if (dp->dom_ifattach) 509 ifp->if_afdata[dp->dom_family] = 510 (*dp->dom_ifattach)(ifp); 511 } 512 513 splx(s); 514 } 515 516 /* 517 * Detach an interface, removing it from the 518 * list of "active" interfaces. 519 */ 520 void 521 if_detach(struct ifnet *ifp) 522 { 523 struct ifaddr *ifa, *next; 524 struct radix_node_head *rnh; 525 int s; 526 int i; 527 struct domain *dp; 528 struct ifnet *iter; 529 int found; 530 531 EVENTHANDLER_INVOKE(ifnet_departure_event, ifp); 532 /* 533 * Remove routes and flush queues. 534 */ 535 s = splnet(); 536 if_down(ifp); 537 #ifdef ALTQ 538 if (ALTQ_IS_ENABLED(&ifp->if_snd)) 539 altq_disable(&ifp->if_snd); 540 if (ALTQ_IS_ATTACHED(&ifp->if_snd)) 541 altq_detach(&ifp->if_snd); 542 #endif 543 544 for (ifa = TAILQ_FIRST(&ifp->if_addrhead); ifa; ifa = next) { 545 next = TAILQ_NEXT(ifa, ifa_link); 546 547 if (ifa->ifa_addr->sa_family == AF_LINK) 548 continue; 549 #ifdef INET 550 /* XXX: Ugly!! ad hoc just for INET */ 551 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET) { 552 struct ifaliasreq ifr; 553 554 bzero(&ifr, sizeof(ifr)); 555 ifr.ifra_addr = *ifa->ifa_addr; 556 if (ifa->ifa_dstaddr) 557 ifr.ifra_broadaddr = *ifa->ifa_dstaddr; 558 if (in_control(NULL, SIOCDIFADDR, (caddr_t)&ifr, ifp, 559 NULL) == 0) 560 continue; 561 } 562 #endif /* INET */ 563 #ifdef INET6 564 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET6) { 565 in6_purgeaddr(ifa); 566 /* ifp_addrhead is already updated */ 567 continue; 568 } 569 #endif /* INET6 */ 570 TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link); 571 IFAFREE(ifa); 572 } 573 574 #ifdef INET6 575 /* 576 * Remove all IPv6 kernel structs related to ifp. This should be done 577 * before removing routing entries below, since IPv6 interface direct 578 * routes are expected to be removed by the IPv6-specific kernel API. 579 * Otherwise, the kernel will detect some inconsistency and bark it. 580 */ 581 in6_ifdetach(ifp); 582 #endif 583 /* 584 * Remove address from ifindex_table[] and maybe decrement if_index. 585 * Clean up all addresses. 586 */ 587 ifnet_byindex(ifp->if_index) = NULL; 588 ifaddr_byindex(ifp->if_index) = NULL; 589 destroy_dev(ifdev_byindex(ifp->if_index)); 590 ifdev_byindex(ifp->if_index) = NULL; 591 592 while (if_index > 0 && ifaddr_byindex(if_index) == NULL) 593 if_index--; 594 595 596 /* We can now free link ifaddr. */ 597 if (!TAILQ_EMPTY(&ifp->if_addrhead)) { 598 ifa = TAILQ_FIRST(&ifp->if_addrhead); 599 TAILQ_REMOVE(&ifp->if_addrhead, ifa, ifa_link); 600 IFAFREE(ifa); 601 } 602 603 /* 604 * Delete all remaining routes using this interface 605 * Unfortuneatly the only way to do this is to slog through 606 * the entire routing table looking for routes which point 607 * to this interface...oh well... 608 */ 609 for (i = 1; i <= AF_MAX; i++) { 610 if ((rnh = rt_tables[i]) == NULL) 611 continue; 612 RADIX_NODE_HEAD_LOCK(rnh); 613 (void) rnh->rnh_walktree(rnh, if_rtdel, ifp); 614 RADIX_NODE_HEAD_UNLOCK(rnh); 615 } 616 617 /* Announce that the interface is gone. */ 618 rt_ifannouncemsg(ifp, IFAN_DEPARTURE); 619 620 IF_AFDATA_LOCK(ifp); 621 for (dp = domains; dp; dp = dp->dom_next) { 622 if (dp->dom_ifdetach && ifp->if_afdata[dp->dom_family]) 623 (*dp->dom_ifdetach)(ifp, 624 ifp->if_afdata[dp->dom_family]); 625 } 626 IF_AFDATA_UNLOCK(ifp); 627 628 #ifdef MAC 629 mac_destroy_ifnet(ifp); 630 #endif /* MAC */ 631 KNOTE_UNLOCKED(&ifp->if_klist, NOTE_EXIT); 632 knlist_clear(&ifp->if_klist, 0); 633 knlist_destroy(&ifp->if_klist); 634 IFNET_WLOCK(); 635 found = 0; 636 TAILQ_FOREACH(iter, &ifnet, if_link) 637 if (iter == ifp) { 638 found = 1; 639 break; 640 } 641 if (found) 642 TAILQ_REMOVE(&ifnet, ifp, if_link); 643 IFNET_WUNLOCK(); 644 mtx_destroy(&ifp->if_snd.ifq_mtx); 645 IF_AFDATA_DESTROY(ifp); 646 splx(s); 647 } 648 649 /* 650 * Delete Routes for a Network Interface 651 * 652 * Called for each routing entry via the rnh->rnh_walktree() call above 653 * to delete all route entries referencing a detaching network interface. 654 * 655 * Arguments: 656 * rn pointer to node in the routing table 657 * arg argument passed to rnh->rnh_walktree() - detaching interface 658 * 659 * Returns: 660 * 0 successful 661 * errno failed - reason indicated 662 * 663 */ 664 static int 665 if_rtdel(struct radix_node *rn, void *arg) 666 { 667 struct rtentry *rt = (struct rtentry *)rn; 668 struct ifnet *ifp = arg; 669 int err; 670 671 if (rt->rt_ifp == ifp) { 672 673 /* 674 * Protect (sorta) against walktree recursion problems 675 * with cloned routes 676 */ 677 if ((rt->rt_flags & RTF_UP) == 0) 678 return (0); 679 680 err = rtrequest(RTM_DELETE, rt_key(rt), rt->rt_gateway, 681 rt_mask(rt), rt->rt_flags, 682 (struct rtentry **) NULL); 683 if (err) { 684 log(LOG_WARNING, "if_rtdel: error %d\n", err); 685 } 686 } 687 688 return (0); 689 } 690 691 #define equal(a1, a2) (bcmp((a1), (a2), ((a1))->sa_len) == 0) 692 693 /* 694 * Locate an interface based on a complete address. 695 */ 696 /*ARGSUSED*/ 697 struct ifaddr * 698 ifa_ifwithaddr(struct sockaddr *addr) 699 { 700 struct ifnet *ifp; 701 struct ifaddr *ifa; 702 703 IFNET_RLOCK(); 704 TAILQ_FOREACH(ifp, &ifnet, if_link) 705 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 706 if (ifa->ifa_addr->sa_family != addr->sa_family) 707 continue; 708 if (equal(addr, ifa->ifa_addr)) 709 goto done; 710 /* IP6 doesn't have broadcast */ 711 if ((ifp->if_flags & IFF_BROADCAST) && 712 ifa->ifa_broadaddr && 713 ifa->ifa_broadaddr->sa_len != 0 && 714 equal(ifa->ifa_broadaddr, addr)) 715 goto done; 716 } 717 ifa = NULL; 718 done: 719 IFNET_RUNLOCK(); 720 return (ifa); 721 } 722 723 /* 724 * Locate the point to point interface with a given destination address. 725 */ 726 /*ARGSUSED*/ 727 struct ifaddr * 728 ifa_ifwithdstaddr(struct sockaddr *addr) 729 { 730 struct ifnet *ifp; 731 struct ifaddr *ifa; 732 733 IFNET_RLOCK(); 734 TAILQ_FOREACH(ifp, &ifnet, if_link) { 735 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) 736 continue; 737 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 738 if (ifa->ifa_addr->sa_family != addr->sa_family) 739 continue; 740 if (ifa->ifa_dstaddr && equal(addr, ifa->ifa_dstaddr)) 741 goto done; 742 } 743 } 744 ifa = NULL; 745 done: 746 IFNET_RUNLOCK(); 747 return (ifa); 748 } 749 750 /* 751 * Find an interface on a specific network. If many, choice 752 * is most specific found. 753 */ 754 struct ifaddr * 755 ifa_ifwithnet(struct sockaddr *addr) 756 { 757 struct ifnet *ifp; 758 struct ifaddr *ifa; 759 struct ifaddr *ifa_maybe = (struct ifaddr *) 0; 760 u_int af = addr->sa_family; 761 char *addr_data = addr->sa_data, *cplim; 762 763 /* 764 * AF_LINK addresses can be looked up directly by their index number, 765 * so do that if we can. 766 */ 767 if (af == AF_LINK) { 768 struct sockaddr_dl *sdl = (struct sockaddr_dl *)addr; 769 if (sdl->sdl_index && sdl->sdl_index <= if_index) 770 return (ifaddr_byindex(sdl->sdl_index)); 771 } 772 773 /* 774 * Scan though each interface, looking for ones that have 775 * addresses in this address family. 776 */ 777 IFNET_RLOCK(); 778 TAILQ_FOREACH(ifp, &ifnet, if_link) { 779 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 780 char *cp, *cp2, *cp3; 781 782 if (ifa->ifa_addr->sa_family != af) 783 next: continue; 784 if (af == AF_INET && ifp->if_flags & IFF_POINTOPOINT) { 785 /* 786 * This is a bit broken as it doesn't 787 * take into account that the remote end may 788 * be a single node in the network we are 789 * looking for. 790 * The trouble is that we don't know the 791 * netmask for the remote end. 792 */ 793 if (ifa->ifa_dstaddr != 0 794 && equal(addr, ifa->ifa_dstaddr)) 795 goto done; 796 } else { 797 /* 798 * if we have a special address handler, 799 * then use it instead of the generic one. 800 */ 801 if (ifa->ifa_claim_addr) { 802 if ((*ifa->ifa_claim_addr)(ifa, addr)) 803 goto done; 804 continue; 805 } 806 807 /* 808 * Scan all the bits in the ifa's address. 809 * If a bit dissagrees with what we are 810 * looking for, mask it with the netmask 811 * to see if it really matters. 812 * (A byte at a time) 813 */ 814 if (ifa->ifa_netmask == 0) 815 continue; 816 cp = addr_data; 817 cp2 = ifa->ifa_addr->sa_data; 818 cp3 = ifa->ifa_netmask->sa_data; 819 cplim = ifa->ifa_netmask->sa_len 820 + (char *)ifa->ifa_netmask; 821 while (cp3 < cplim) 822 if ((*cp++ ^ *cp2++) & *cp3++) 823 goto next; /* next address! */ 824 /* 825 * If the netmask of what we just found 826 * is more specific than what we had before 827 * (if we had one) then remember the new one 828 * before continuing to search 829 * for an even better one. 830 */ 831 if (ifa_maybe == 0 || 832 rn_refines((caddr_t)ifa->ifa_netmask, 833 (caddr_t)ifa_maybe->ifa_netmask)) 834 ifa_maybe = ifa; 835 } 836 } 837 } 838 ifa = ifa_maybe; 839 done: 840 IFNET_RUNLOCK(); 841 return (ifa); 842 } 843 844 /* 845 * Find an interface address specific to an interface best matching 846 * a given address. 847 */ 848 struct ifaddr * 849 ifaof_ifpforaddr(struct sockaddr *addr, struct ifnet *ifp) 850 { 851 struct ifaddr *ifa; 852 char *cp, *cp2, *cp3; 853 char *cplim; 854 struct ifaddr *ifa_maybe = 0; 855 u_int af = addr->sa_family; 856 857 if (af >= AF_MAX) 858 return (0); 859 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 860 if (ifa->ifa_addr->sa_family != af) 861 continue; 862 if (ifa_maybe == 0) 863 ifa_maybe = ifa; 864 if (ifa->ifa_netmask == 0) { 865 if (equal(addr, ifa->ifa_addr) || 866 (ifa->ifa_dstaddr && equal(addr, ifa->ifa_dstaddr))) 867 goto done; 868 continue; 869 } 870 if (ifp->if_flags & IFF_POINTOPOINT) { 871 if (equal(addr, ifa->ifa_dstaddr)) 872 goto done; 873 } else { 874 cp = addr->sa_data; 875 cp2 = ifa->ifa_addr->sa_data; 876 cp3 = ifa->ifa_netmask->sa_data; 877 cplim = ifa->ifa_netmask->sa_len + (char *)ifa->ifa_netmask; 878 for (; cp3 < cplim; cp3++) 879 if ((*cp++ ^ *cp2++) & *cp3) 880 break; 881 if (cp3 == cplim) 882 goto done; 883 } 884 } 885 ifa = ifa_maybe; 886 done: 887 return (ifa); 888 } 889 890 #include <net/route.h> 891 892 /* 893 * Default action when installing a route with a Link Level gateway. 894 * Lookup an appropriate real ifa to point to. 895 * This should be moved to /sys/net/link.c eventually. 896 */ 897 static void 898 link_rtrequest(int cmd, struct rtentry *rt, struct rt_addrinfo *info) 899 { 900 struct ifaddr *ifa, *oifa; 901 struct sockaddr *dst; 902 struct ifnet *ifp; 903 904 RT_LOCK_ASSERT(rt); 905 906 if (cmd != RTM_ADD || ((ifa = rt->rt_ifa) == 0) || 907 ((ifp = ifa->ifa_ifp) == 0) || ((dst = rt_key(rt)) == 0)) 908 return; 909 ifa = ifaof_ifpforaddr(dst, ifp); 910 if (ifa) { 911 IFAREF(ifa); /* XXX */ 912 oifa = rt->rt_ifa; 913 rt->rt_ifa = ifa; 914 IFAFREE(oifa); 915 if (ifa->ifa_rtrequest && ifa->ifa_rtrequest != link_rtrequest) 916 ifa->ifa_rtrequest(cmd, rt, info); 917 } 918 } 919 920 /* 921 * Mark an interface down and notify protocols of 922 * the transition. 923 * NOTE: must be called at splnet or eqivalent. 924 */ 925 static void 926 if_unroute(struct ifnet *ifp, int flag, int fam) 927 { 928 struct ifaddr *ifa; 929 930 ifp->if_flags &= ~flag; 931 getmicrotime(&ifp->if_lastchange); 932 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 933 if (fam == PF_UNSPEC || (fam == ifa->ifa_addr->sa_family)) 934 pfctlinput(PRC_IFDOWN, ifa->ifa_addr); 935 if_qflush(&ifp->if_snd); 936 rt_ifmsg(ifp); 937 } 938 939 /* 940 * Mark an interface up and notify protocols of 941 * the transition. 942 * NOTE: must be called at splnet or eqivalent. 943 */ 944 static void 945 if_route(struct ifnet *ifp, int flag, int fam) 946 { 947 struct ifaddr *ifa; 948 949 ifp->if_flags |= flag; 950 getmicrotime(&ifp->if_lastchange); 951 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 952 if (fam == PF_UNSPEC || (fam == ifa->ifa_addr->sa_family)) 953 pfctlinput(PRC_IFUP, ifa->ifa_addr); 954 rt_ifmsg(ifp); 955 #ifdef INET6 956 in6_if_up(ifp); 957 #endif 958 } 959 960 void (*vlan_link_state_p)(struct ifnet *, int); /* XXX: private from if_vlan */ 961 962 /* 963 * Handle a change in the interface link state. 964 */ 965 void 966 if_link_state_change(struct ifnet *ifp, int link_state) 967 { 968 int link; 969 970 /* Notify that the link state has changed. */ 971 if (ifp->if_link_state != link_state) { 972 ifp->if_link_state = link_state; 973 rt_ifmsg(ifp); 974 if (link_state == LINK_STATE_UP) 975 link = NOTE_LINKUP; 976 else if (link_state == LINK_STATE_DOWN) 977 link = NOTE_LINKDOWN; 978 else 979 link = NOTE_LINKINV; 980 KNOTE_UNLOCKED(&ifp->if_klist, link); 981 if (ifp->if_nvlans != 0) 982 (*vlan_link_state_p)(ifp, link); 983 984 if ((ifp->if_type == IFT_ETHER || ifp->if_type == IFT_L2VLAN) && 985 IFP2AC(ifp)->ac_netgraph != NULL) 986 (*ng_ether_link_state_p)(ifp, link_state); 987 988 log(LOG_NOTICE, "%s: link state changed to %s\n", ifp->if_xname, 989 (link_state == LINK_STATE_UP) ? "UP" : "DOWN" ); 990 } 991 } 992 993 /* 994 * Mark an interface down and notify protocols of 995 * the transition. 996 * NOTE: must be called at splnet or eqivalent. 997 */ 998 void 999 if_down(struct ifnet *ifp) 1000 { 1001 1002 if_unroute(ifp, IFF_UP, AF_UNSPEC); 1003 } 1004 1005 /* 1006 * Mark an interface up and notify protocols of 1007 * the transition. 1008 * NOTE: must be called at splnet or eqivalent. 1009 */ 1010 void 1011 if_up(struct ifnet *ifp) 1012 { 1013 1014 if_route(ifp, IFF_UP, AF_UNSPEC); 1015 } 1016 1017 /* 1018 * Flush an interface queue. 1019 */ 1020 static void 1021 if_qflush(struct ifaltq *ifq) 1022 { 1023 struct mbuf *m, *n; 1024 1025 IFQ_LOCK(ifq); 1026 #ifdef ALTQ 1027 if (ALTQ_IS_ENABLED(ifq)) 1028 ALTQ_PURGE(ifq); 1029 #endif 1030 n = ifq->ifq_head; 1031 while ((m = n) != 0) { 1032 n = m->m_act; 1033 m_freem(m); 1034 } 1035 ifq->ifq_head = 0; 1036 ifq->ifq_tail = 0; 1037 ifq->ifq_len = 0; 1038 IFQ_UNLOCK(ifq); 1039 } 1040 1041 /* 1042 * Handle interface watchdog timer routines. Called 1043 * from softclock, we decrement timers (if set) and 1044 * call the appropriate interface routine on expiration. 1045 * 1046 * XXXRW: Note that because timeouts run with Giant, if_watchdog() is called 1047 * holding Giant. If we switch to an MPSAFE callout, we likely need to grab 1048 * Giant before entering if_watchdog() on an IFF_NEEDSGIANT interface. 1049 */ 1050 static void 1051 if_slowtimo(void *arg) 1052 { 1053 struct ifnet *ifp; 1054 int s = splimp(); 1055 1056 IFNET_RLOCK(); 1057 TAILQ_FOREACH(ifp, &ifnet, if_link) { 1058 if (ifp->if_timer == 0 || --ifp->if_timer) 1059 continue; 1060 if (ifp->if_watchdog) 1061 (*ifp->if_watchdog)(ifp); 1062 } 1063 IFNET_RUNLOCK(); 1064 splx(s); 1065 timeout(if_slowtimo, (void *)0, hz / IFNET_SLOWHZ); 1066 } 1067 1068 /* 1069 * Map interface name to 1070 * interface structure pointer. 1071 */ 1072 struct ifnet * 1073 ifunit(const char *name) 1074 { 1075 struct ifnet *ifp; 1076 1077 IFNET_RLOCK(); 1078 TAILQ_FOREACH(ifp, &ifnet, if_link) { 1079 if (strncmp(name, ifp->if_xname, IFNAMSIZ) == 0) 1080 break; 1081 } 1082 IFNET_RUNLOCK(); 1083 return (ifp); 1084 } 1085 1086 /* 1087 * Hardware specific interface ioctls. 1088 */ 1089 static int 1090 ifhwioctl(u_long cmd, struct ifnet *ifp, caddr_t data, struct thread *td) 1091 { 1092 struct ifreq *ifr; 1093 struct ifstat *ifs; 1094 int error = 0; 1095 int new_flags; 1096 size_t namelen, onamelen; 1097 char new_name[IFNAMSIZ]; 1098 struct ifaddr *ifa; 1099 struct sockaddr_dl *sdl; 1100 1101 ifr = (struct ifreq *)data; 1102 switch (cmd) { 1103 case SIOCGIFINDEX: 1104 ifr->ifr_index = ifp->if_index; 1105 break; 1106 1107 case SIOCGIFFLAGS: 1108 ifr->ifr_flags = ifp->if_flags & 0xffff; 1109 ifr->ifr_flagshigh = ifp->if_flags >> 16; 1110 break; 1111 1112 case SIOCGIFCAP: 1113 ifr->ifr_reqcap = ifp->if_capabilities; 1114 ifr->ifr_curcap = ifp->if_capenable; 1115 break; 1116 1117 #ifdef MAC 1118 case SIOCGIFMAC: 1119 error = mac_ioctl_ifnet_get(td->td_ucred, ifr, ifp); 1120 break; 1121 #endif 1122 1123 case SIOCGIFMETRIC: 1124 ifr->ifr_metric = ifp->if_metric; 1125 break; 1126 1127 case SIOCGIFMTU: 1128 ifr->ifr_mtu = ifp->if_mtu; 1129 break; 1130 1131 case SIOCGIFPHYS: 1132 ifr->ifr_phys = ifp->if_physical; 1133 break; 1134 1135 case SIOCSIFFLAGS: 1136 error = suser(td); 1137 if (error) 1138 return (error); 1139 new_flags = (ifr->ifr_flags & 0xffff) | 1140 (ifr->ifr_flagshigh << 16); 1141 if (ifp->if_flags & IFF_SMART) { 1142 /* Smart drivers twiddle their own routes */ 1143 } else if (ifp->if_flags & IFF_UP && 1144 (new_flags & IFF_UP) == 0) { 1145 int s = splimp(); 1146 if_down(ifp); 1147 splx(s); 1148 } else if (new_flags & IFF_UP && 1149 (ifp->if_flags & IFF_UP) == 0) { 1150 int s = splimp(); 1151 if_up(ifp); 1152 splx(s); 1153 } 1154 ifp->if_flags = (ifp->if_flags & IFF_CANTCHANGE) | 1155 (new_flags &~ IFF_CANTCHANGE); 1156 if (new_flags & IFF_PPROMISC) { 1157 /* Permanently promiscuous mode requested */ 1158 ifp->if_flags |= IFF_PROMISC; 1159 } else if (ifp->if_pcount == 0) { 1160 ifp->if_flags &= ~IFF_PROMISC; 1161 } 1162 if (ifp->if_ioctl) { 1163 IFF_LOCKGIANT(ifp); 1164 (void) (*ifp->if_ioctl)(ifp, cmd, data); 1165 IFF_UNLOCKGIANT(ifp); 1166 } 1167 getmicrotime(&ifp->if_lastchange); 1168 break; 1169 1170 case SIOCSIFCAP: 1171 error = suser(td); 1172 if (error) 1173 return (error); 1174 if (ifp->if_ioctl == NULL) 1175 return (EOPNOTSUPP); 1176 if (ifr->ifr_reqcap & ~ifp->if_capabilities) 1177 return (EINVAL); 1178 IFF_LOCKGIANT(ifp); 1179 error = (*ifp->if_ioctl)(ifp, cmd, data); 1180 IFF_UNLOCKGIANT(ifp); 1181 if (error == 0) 1182 getmicrotime(&ifp->if_lastchange); 1183 break; 1184 1185 #ifdef MAC 1186 case SIOCSIFMAC: 1187 error = mac_ioctl_ifnet_set(td->td_ucred, ifr, ifp); 1188 break; 1189 #endif 1190 1191 case SIOCSIFNAME: 1192 error = suser(td); 1193 if (error != 0) 1194 return (error); 1195 error = copyinstr(ifr->ifr_data, new_name, IFNAMSIZ, NULL); 1196 if (error != 0) 1197 return (error); 1198 if (new_name[0] == '\0') 1199 return (EINVAL); 1200 if (ifunit(new_name) != NULL) 1201 return (EEXIST); 1202 1203 EVENTHANDLER_INVOKE(ifnet_departure_event, ifp); 1204 /* Announce the departure of the interface. */ 1205 rt_ifannouncemsg(ifp, IFAN_DEPARTURE); 1206 1207 log(LOG_INFO, "%s: changing name to '%s'\n", 1208 ifp->if_xname, new_name); 1209 1210 strlcpy(ifp->if_xname, new_name, sizeof(ifp->if_xname)); 1211 ifa = ifaddr_byindex(ifp->if_index); 1212 IFA_LOCK(ifa); 1213 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1214 namelen = strlen(new_name); 1215 onamelen = sdl->sdl_nlen; 1216 /* 1217 * Move the address if needed. This is safe because we 1218 * allocate space for a name of length IFNAMSIZ when we 1219 * create this in if_attach(). 1220 */ 1221 if (namelen != onamelen) { 1222 bcopy(sdl->sdl_data + onamelen, 1223 sdl->sdl_data + namelen, sdl->sdl_alen); 1224 } 1225 bcopy(new_name, sdl->sdl_data, namelen); 1226 sdl->sdl_nlen = namelen; 1227 sdl = (struct sockaddr_dl *)ifa->ifa_netmask; 1228 bzero(sdl->sdl_data, onamelen); 1229 while (namelen != 0) 1230 sdl->sdl_data[--namelen] = 0xff; 1231 IFA_UNLOCK(ifa); 1232 1233 EVENTHANDLER_INVOKE(ifnet_arrival_event, ifp); 1234 /* Announce the return of the interface. */ 1235 rt_ifannouncemsg(ifp, IFAN_ARRIVAL); 1236 break; 1237 1238 case SIOCSIFMETRIC: 1239 error = suser(td); 1240 if (error) 1241 return (error); 1242 ifp->if_metric = ifr->ifr_metric; 1243 getmicrotime(&ifp->if_lastchange); 1244 break; 1245 1246 case SIOCSIFPHYS: 1247 error = suser(td); 1248 if (error) 1249 return (error); 1250 if (ifp->if_ioctl == NULL) 1251 return (EOPNOTSUPP); 1252 IFF_LOCKGIANT(ifp); 1253 error = (*ifp->if_ioctl)(ifp, cmd, data); 1254 IFF_UNLOCKGIANT(ifp); 1255 if (error == 0) 1256 getmicrotime(&ifp->if_lastchange); 1257 break; 1258 1259 case SIOCSIFMTU: 1260 { 1261 u_long oldmtu = ifp->if_mtu; 1262 1263 error = suser(td); 1264 if (error) 1265 return (error); 1266 if (ifr->ifr_mtu < IF_MINMTU || ifr->ifr_mtu > IF_MAXMTU) 1267 return (EINVAL); 1268 if (ifp->if_ioctl == NULL) 1269 return (EOPNOTSUPP); 1270 IFF_LOCKGIANT(ifp); 1271 error = (*ifp->if_ioctl)(ifp, cmd, data); 1272 IFF_UNLOCKGIANT(ifp); 1273 if (error == 0) { 1274 getmicrotime(&ifp->if_lastchange); 1275 rt_ifmsg(ifp); 1276 } 1277 /* 1278 * If the link MTU changed, do network layer specific procedure. 1279 */ 1280 if (ifp->if_mtu != oldmtu) { 1281 #ifdef INET6 1282 nd6_setmtu(ifp); 1283 #endif 1284 } 1285 break; 1286 } 1287 1288 case SIOCADDMULTI: 1289 case SIOCDELMULTI: 1290 error = suser(td); 1291 if (error) 1292 return (error); 1293 1294 /* Don't allow group membership on non-multicast interfaces. */ 1295 if ((ifp->if_flags & IFF_MULTICAST) == 0) 1296 return (EOPNOTSUPP); 1297 1298 /* Don't let users screw up protocols' entries. */ 1299 if (ifr->ifr_addr.sa_family != AF_LINK) 1300 return (EINVAL); 1301 1302 if (cmd == SIOCADDMULTI) { 1303 struct ifmultiaddr *ifma; 1304 error = if_addmulti(ifp, &ifr->ifr_addr, &ifma); 1305 } else { 1306 error = if_delmulti(ifp, &ifr->ifr_addr); 1307 } 1308 if (error == 0) 1309 getmicrotime(&ifp->if_lastchange); 1310 break; 1311 1312 case SIOCSIFPHYADDR: 1313 case SIOCDIFPHYADDR: 1314 #ifdef INET6 1315 case SIOCSIFPHYADDR_IN6: 1316 #endif 1317 case SIOCSLIFPHYADDR: 1318 case SIOCSIFMEDIA: 1319 case SIOCSIFGENERIC: 1320 error = suser(td); 1321 if (error) 1322 return (error); 1323 if (ifp->if_ioctl == NULL) 1324 return (EOPNOTSUPP); 1325 IFF_LOCKGIANT(ifp); 1326 error = (*ifp->if_ioctl)(ifp, cmd, data); 1327 IFF_UNLOCKGIANT(ifp); 1328 if (error == 0) 1329 getmicrotime(&ifp->if_lastchange); 1330 break; 1331 1332 case SIOCGIFSTATUS: 1333 ifs = (struct ifstat *)data; 1334 ifs->ascii[0] = '\0'; 1335 1336 case SIOCGIFPSRCADDR: 1337 case SIOCGIFPDSTADDR: 1338 case SIOCGLIFPHYADDR: 1339 case SIOCGIFMEDIA: 1340 case SIOCGIFGENERIC: 1341 if (ifp->if_ioctl == NULL) 1342 return (EOPNOTSUPP); 1343 IFF_LOCKGIANT(ifp); 1344 error = (*ifp->if_ioctl)(ifp, cmd, data); 1345 IFF_UNLOCKGIANT(ifp); 1346 break; 1347 1348 case SIOCSIFLLADDR: 1349 error = suser(td); 1350 if (error) 1351 return (error); 1352 error = if_setlladdr(ifp, 1353 ifr->ifr_addr.sa_data, ifr->ifr_addr.sa_len); 1354 break; 1355 1356 default: 1357 error = ENOIOCTL; 1358 break; 1359 } 1360 return (error); 1361 } 1362 1363 /* 1364 * Interface ioctls. 1365 */ 1366 int 1367 ifioctl(struct socket *so, u_long cmd, caddr_t data, struct thread *td) 1368 { 1369 struct ifnet *ifp; 1370 struct ifreq *ifr; 1371 int error; 1372 int oif_flags; 1373 1374 switch (cmd) { 1375 case SIOCGIFCONF: 1376 case OSIOCGIFCONF: 1377 return (ifconf(cmd, data)); 1378 } 1379 ifr = (struct ifreq *)data; 1380 1381 switch (cmd) { 1382 case SIOCIFCREATE: 1383 case SIOCIFDESTROY: 1384 if ((error = suser(td)) != 0) 1385 return (error); 1386 return ((cmd == SIOCIFCREATE) ? 1387 if_clone_create(ifr->ifr_name, sizeof(ifr->ifr_name)) : 1388 if_clone_destroy(ifr->ifr_name)); 1389 1390 case SIOCIFGCLONERS: 1391 return (if_clone_list((struct if_clonereq *)data)); 1392 } 1393 1394 ifp = ifunit(ifr->ifr_name); 1395 if (ifp == 0) 1396 return (ENXIO); 1397 1398 error = ifhwioctl(cmd, ifp, data, td); 1399 if (error != ENOIOCTL) 1400 return (error); 1401 1402 oif_flags = ifp->if_flags; 1403 if (so->so_proto == 0) 1404 return (EOPNOTSUPP); 1405 #ifndef COMPAT_43 1406 error = ((*so->so_proto->pr_usrreqs->pru_control)(so, cmd, 1407 data, 1408 ifp, td)); 1409 #else 1410 { 1411 int ocmd = cmd; 1412 1413 switch (cmd) { 1414 1415 case SIOCSIFDSTADDR: 1416 case SIOCSIFADDR: 1417 case SIOCSIFBRDADDR: 1418 case SIOCSIFNETMASK: 1419 #if BYTE_ORDER != BIG_ENDIAN 1420 if (ifr->ifr_addr.sa_family == 0 && 1421 ifr->ifr_addr.sa_len < 16) { 1422 ifr->ifr_addr.sa_family = ifr->ifr_addr.sa_len; 1423 ifr->ifr_addr.sa_len = 16; 1424 } 1425 #else 1426 if (ifr->ifr_addr.sa_len == 0) 1427 ifr->ifr_addr.sa_len = 16; 1428 #endif 1429 break; 1430 1431 case OSIOCGIFADDR: 1432 cmd = SIOCGIFADDR; 1433 break; 1434 1435 case OSIOCGIFDSTADDR: 1436 cmd = SIOCGIFDSTADDR; 1437 break; 1438 1439 case OSIOCGIFBRDADDR: 1440 cmd = SIOCGIFBRDADDR; 1441 break; 1442 1443 case OSIOCGIFNETMASK: 1444 cmd = SIOCGIFNETMASK; 1445 } 1446 error = ((*so->so_proto->pr_usrreqs->pru_control)(so, 1447 cmd, 1448 data, 1449 ifp, td)); 1450 switch (ocmd) { 1451 1452 case OSIOCGIFADDR: 1453 case OSIOCGIFDSTADDR: 1454 case OSIOCGIFBRDADDR: 1455 case OSIOCGIFNETMASK: 1456 *(u_short *)&ifr->ifr_addr = ifr->ifr_addr.sa_family; 1457 1458 } 1459 } 1460 #endif /* COMPAT_43 */ 1461 1462 if ((oif_flags ^ ifp->if_flags) & IFF_UP) { 1463 #ifdef INET6 1464 DELAY(100);/* XXX: temporary workaround for fxp issue*/ 1465 if (ifp->if_flags & IFF_UP) { 1466 int s = splimp(); 1467 in6_if_up(ifp); 1468 splx(s); 1469 } 1470 #endif 1471 } 1472 return (error); 1473 } 1474 1475 /* 1476 * Set/clear promiscuous mode on interface ifp based on the truth value 1477 * of pswitch. The calls are reference counted so that only the first 1478 * "on" request actually has an effect, as does the final "off" request. 1479 * Results are undefined if the "off" and "on" requests are not matched. 1480 */ 1481 int 1482 ifpromisc(struct ifnet *ifp, int pswitch) 1483 { 1484 struct ifreq ifr; 1485 int error; 1486 int oldflags, oldpcount; 1487 1488 oldpcount = ifp->if_pcount; 1489 oldflags = ifp->if_flags; 1490 if (ifp->if_flags & IFF_PPROMISC) { 1491 /* Do nothing if device is in permanently promiscuous mode */ 1492 ifp->if_pcount += pswitch ? 1 : -1; 1493 return (0); 1494 } 1495 if (pswitch) { 1496 /* 1497 * If the device is not configured up, we cannot put it in 1498 * promiscuous mode. 1499 */ 1500 if ((ifp->if_flags & IFF_UP) == 0) 1501 return (ENETDOWN); 1502 if (ifp->if_pcount++ != 0) 1503 return (0); 1504 ifp->if_flags |= IFF_PROMISC; 1505 } else { 1506 if (--ifp->if_pcount > 0) 1507 return (0); 1508 ifp->if_flags &= ~IFF_PROMISC; 1509 } 1510 ifr.ifr_flags = ifp->if_flags & 0xffff; 1511 ifr.ifr_flagshigh = ifp->if_flags >> 16; 1512 IFF_LOCKGIANT(ifp); 1513 error = (*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr); 1514 IFF_UNLOCKGIANT(ifp); 1515 if (error == 0) { 1516 log(LOG_INFO, "%s: promiscuous mode %s\n", 1517 ifp->if_xname, 1518 (ifp->if_flags & IFF_PROMISC) ? "enabled" : "disabled"); 1519 rt_ifmsg(ifp); 1520 } else { 1521 ifp->if_pcount = oldpcount; 1522 ifp->if_flags = oldflags; 1523 } 1524 return error; 1525 } 1526 1527 /* 1528 * Return interface configuration 1529 * of system. List may be used 1530 * in later ioctl's (above) to get 1531 * other information. 1532 */ 1533 /*ARGSUSED*/ 1534 static int 1535 ifconf(u_long cmd, caddr_t data) 1536 { 1537 struct ifconf *ifc = (struct ifconf *)data; 1538 struct ifnet *ifp; 1539 struct ifaddr *ifa; 1540 struct ifreq ifr; 1541 struct sbuf *sb; 1542 int error, full = 0, valid_len, max_len; 1543 1544 /* Limit initial buffer size to MAXPHYS to avoid DoS from userspace. */ 1545 max_len = MAXPHYS - 1; 1546 1547 again: 1548 if (ifc->ifc_len <= max_len) { 1549 max_len = ifc->ifc_len; 1550 full = 1; 1551 } 1552 sb = sbuf_new(NULL, NULL, max_len + 1, SBUF_FIXEDLEN); 1553 max_len = 0; 1554 valid_len = 0; 1555 1556 IFNET_RLOCK(); /* could sleep XXX */ 1557 TAILQ_FOREACH(ifp, &ifnet, if_link) { 1558 int addrs; 1559 1560 if (strlcpy(ifr.ifr_name, ifp->if_xname, sizeof(ifr.ifr_name)) 1561 >= sizeof(ifr.ifr_name)) 1562 return (ENAMETOOLONG); 1563 1564 addrs = 0; 1565 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1566 struct sockaddr *sa = ifa->ifa_addr; 1567 1568 if (jailed(curthread->td_ucred) && 1569 prison_if(curthread->td_ucred, sa)) 1570 continue; 1571 addrs++; 1572 #ifdef COMPAT_43 1573 if (cmd == OSIOCGIFCONF) { 1574 struct osockaddr *osa = 1575 (struct osockaddr *)&ifr.ifr_addr; 1576 ifr.ifr_addr = *sa; 1577 osa->sa_family = sa->sa_family; 1578 sbuf_bcat(sb, &ifr, sizeof(ifr)); 1579 max_len += sizeof(ifr); 1580 } else 1581 #endif 1582 if (sa->sa_len <= sizeof(*sa)) { 1583 ifr.ifr_addr = *sa; 1584 sbuf_bcat(sb, &ifr, sizeof(ifr)); 1585 max_len += sizeof(ifr); 1586 } else { 1587 sbuf_bcat(sb, &ifr, 1588 offsetof(struct ifreq, ifr_addr)); 1589 max_len += offsetof(struct ifreq, ifr_addr); 1590 sbuf_bcat(sb, sa, sa->sa_len); 1591 max_len += sa->sa_len; 1592 } 1593 1594 if (!sbuf_overflowed(sb)) 1595 valid_len = sbuf_len(sb); 1596 } 1597 if (addrs == 0) { 1598 bzero((caddr_t)&ifr.ifr_addr, sizeof(ifr.ifr_addr)); 1599 sbuf_bcat(sb, &ifr, sizeof(ifr)); 1600 max_len += sizeof(ifr); 1601 1602 if (!sbuf_overflowed(sb)) 1603 valid_len = sbuf_len(sb); 1604 } 1605 } 1606 IFNET_RUNLOCK(); 1607 1608 /* 1609 * If we didn't allocate enough space (uncommon), try again. If 1610 * we have already allocated as much space as we are allowed, 1611 * return what we've got. 1612 */ 1613 if (valid_len != max_len && !full) { 1614 sbuf_delete(sb); 1615 goto again; 1616 } 1617 1618 ifc->ifc_len = valid_len; 1619 sbuf_finish(sb); 1620 error = copyout(sbuf_data(sb), ifc->ifc_req, ifc->ifc_len); 1621 sbuf_delete(sb); 1622 return (error); 1623 } 1624 1625 /* 1626 * Just like if_promisc(), but for all-multicast-reception mode. 1627 */ 1628 int 1629 if_allmulti(struct ifnet *ifp, int onswitch) 1630 { 1631 int error = 0; 1632 int s = splimp(); 1633 struct ifreq ifr; 1634 1635 if (onswitch) { 1636 if (ifp->if_amcount++ == 0) { 1637 ifp->if_flags |= IFF_ALLMULTI; 1638 ifr.ifr_flags = ifp->if_flags & 0xffff; 1639 ifr.ifr_flagshigh = ifp->if_flags >> 16; 1640 IFF_LOCKGIANT(ifp); 1641 error = ifp->if_ioctl(ifp, SIOCSIFFLAGS, (caddr_t)&ifr); 1642 IFF_UNLOCKGIANT(ifp); 1643 } 1644 } else { 1645 if (ifp->if_amcount > 1) { 1646 ifp->if_amcount--; 1647 } else { 1648 ifp->if_amcount = 0; 1649 ifp->if_flags &= ~IFF_ALLMULTI; 1650 ifr.ifr_flags = ifp->if_flags & 0xffff;; 1651 ifr.ifr_flagshigh = ifp->if_flags >> 16; 1652 IFF_LOCKGIANT(ifp); 1653 error = ifp->if_ioctl(ifp, SIOCSIFFLAGS, (caddr_t)&ifr); 1654 IFF_UNLOCKGIANT(ifp); 1655 } 1656 } 1657 splx(s); 1658 1659 if (error == 0) 1660 rt_ifmsg(ifp); 1661 return error; 1662 } 1663 1664 /* 1665 * Add a multicast listenership to the interface in question. 1666 * The link layer provides a routine which converts 1667 */ 1668 int 1669 if_addmulti(struct ifnet *ifp, struct sockaddr *sa, struct ifmultiaddr **retifma) 1670 { 1671 struct sockaddr *llsa, *dupsa; 1672 int error, s; 1673 struct ifmultiaddr *ifma; 1674 1675 /* 1676 * If the matching multicast address already exists 1677 * then don't add a new one, just add a reference 1678 */ 1679 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 1680 if (equal(sa, ifma->ifma_addr)) { 1681 ifma->ifma_refcount++; 1682 if (retifma) 1683 *retifma = ifma; 1684 return 0; 1685 } 1686 } 1687 1688 /* 1689 * Give the link layer a chance to accept/reject it, and also 1690 * find out which AF_LINK address this maps to, if it isn't one 1691 * already. 1692 */ 1693 if (ifp->if_resolvemulti) { 1694 error = ifp->if_resolvemulti(ifp, &llsa, sa); 1695 if (error) return error; 1696 } else { 1697 llsa = 0; 1698 } 1699 1700 MALLOC(ifma, struct ifmultiaddr *, sizeof *ifma, M_IFMADDR, M_WAITOK); 1701 MALLOC(dupsa, struct sockaddr *, sa->sa_len, M_IFMADDR, M_WAITOK); 1702 bcopy(sa, dupsa, sa->sa_len); 1703 1704 ifma->ifma_addr = dupsa; 1705 ifma->ifma_lladdr = llsa; 1706 ifma->ifma_ifp = ifp; 1707 ifma->ifma_refcount = 1; 1708 ifma->ifma_protospec = 0; 1709 rt_newmaddrmsg(RTM_NEWMADDR, ifma); 1710 1711 /* 1712 * Some network interfaces can scan the address list at 1713 * interrupt time; lock them out. 1714 */ 1715 s = splimp(); 1716 TAILQ_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link); 1717 splx(s); 1718 if (retifma != NULL) 1719 *retifma = ifma; 1720 1721 if (llsa != 0) { 1722 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) { 1723 if (equal(ifma->ifma_addr, llsa)) 1724 break; 1725 } 1726 if (ifma) { 1727 ifma->ifma_refcount++; 1728 } else { 1729 MALLOC(ifma, struct ifmultiaddr *, sizeof *ifma, 1730 M_IFMADDR, M_WAITOK); 1731 MALLOC(dupsa, struct sockaddr *, llsa->sa_len, 1732 M_IFMADDR, M_WAITOK); 1733 bcopy(llsa, dupsa, llsa->sa_len); 1734 ifma->ifma_addr = dupsa; 1735 ifma->ifma_lladdr = NULL; 1736 ifma->ifma_ifp = ifp; 1737 ifma->ifma_refcount = 1; 1738 ifma->ifma_protospec = 0; 1739 s = splimp(); 1740 TAILQ_INSERT_HEAD(&ifp->if_multiaddrs, ifma, ifma_link); 1741 splx(s); 1742 } 1743 } 1744 /* 1745 * We are certain we have added something, so call down to the 1746 * interface to let them know about it. 1747 */ 1748 s = splimp(); 1749 IFF_LOCKGIANT(ifp); 1750 ifp->if_ioctl(ifp, SIOCADDMULTI, 0); 1751 IFF_UNLOCKGIANT(ifp); 1752 splx(s); 1753 1754 return 0; 1755 } 1756 1757 /* 1758 * Remove a reference to a multicast address on this interface. Yell 1759 * if the request does not match an existing membership. 1760 */ 1761 int 1762 if_delmulti(struct ifnet *ifp, struct sockaddr *sa) 1763 { 1764 struct ifmultiaddr *ifma; 1765 int s; 1766 1767 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) 1768 if (equal(sa, ifma->ifma_addr)) 1769 break; 1770 if (ifma == 0) 1771 return ENOENT; 1772 1773 if (ifma->ifma_refcount > 1) { 1774 ifma->ifma_refcount--; 1775 return 0; 1776 } 1777 1778 rt_newmaddrmsg(RTM_DELMADDR, ifma); 1779 sa = ifma->ifma_lladdr; 1780 s = splimp(); 1781 TAILQ_REMOVE(&ifp->if_multiaddrs, ifma, ifma_link); 1782 /* 1783 * Make sure the interface driver is notified 1784 * in the case of a link layer mcast group being left. 1785 */ 1786 if (ifma->ifma_addr->sa_family == AF_LINK && sa == 0) { 1787 IFF_LOCKGIANT(ifp); 1788 ifp->if_ioctl(ifp, SIOCDELMULTI, 0); 1789 IFF_UNLOCKGIANT(ifp); 1790 } 1791 splx(s); 1792 free(ifma->ifma_addr, M_IFMADDR); 1793 free(ifma, M_IFMADDR); 1794 if (sa == 0) 1795 return 0; 1796 1797 /* 1798 * Now look for the link-layer address which corresponds to 1799 * this network address. It had been squirreled away in 1800 * ifma->ifma_lladdr for this purpose (so we don't have 1801 * to call ifp->if_resolvemulti() again), and we saved that 1802 * value in sa above. If some nasty deleted the 1803 * link-layer address out from underneath us, we can deal because 1804 * the address we stored was is not the same as the one which was 1805 * in the record for the link-layer address. (So we don't complain 1806 * in that case.) 1807 */ 1808 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) 1809 if (equal(sa, ifma->ifma_addr)) 1810 break; 1811 if (ifma == 0) 1812 return 0; 1813 1814 if (ifma->ifma_refcount > 1) { 1815 ifma->ifma_refcount--; 1816 return 0; 1817 } 1818 1819 s = splimp(); 1820 TAILQ_REMOVE(&ifp->if_multiaddrs, ifma, ifma_link); 1821 IFF_LOCKGIANT(ifp); 1822 ifp->if_ioctl(ifp, SIOCDELMULTI, 0); 1823 IFF_UNLOCKGIANT(ifp); 1824 splx(s); 1825 free(ifma->ifma_addr, M_IFMADDR); 1826 free(sa, M_IFMADDR); 1827 free(ifma, M_IFMADDR); 1828 1829 return 0; 1830 } 1831 1832 /* 1833 * Set the link layer address on an interface. 1834 * 1835 * At this time we only support certain types of interfaces, 1836 * and we don't allow the length of the address to change. 1837 */ 1838 int 1839 if_setlladdr(struct ifnet *ifp, const u_char *lladdr, int len) 1840 { 1841 struct sockaddr_dl *sdl; 1842 struct ifaddr *ifa; 1843 struct ifreq ifr; 1844 1845 ifa = ifaddr_byindex(ifp->if_index); 1846 if (ifa == NULL) 1847 return (EINVAL); 1848 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 1849 if (sdl == NULL) 1850 return (EINVAL); 1851 if (len != sdl->sdl_alen) /* don't allow length to change */ 1852 return (EINVAL); 1853 switch (ifp->if_type) { 1854 case IFT_ETHER: /* these types use struct arpcom */ 1855 case IFT_FDDI: 1856 case IFT_XETHER: 1857 case IFT_ISO88025: 1858 case IFT_L2VLAN: 1859 bcopy(lladdr, IFP2AC(ifp)->ac_enaddr, len); 1860 /* 1861 * XXX We also need to store the lladdr in LLADDR(sdl), 1862 * which is done below. This is a pain because we must 1863 * remember to keep the info in sync. 1864 */ 1865 /* FALLTHROUGH */ 1866 case IFT_ARCNET: 1867 bcopy(lladdr, LLADDR(sdl), len); 1868 break; 1869 default: 1870 return (ENODEV); 1871 } 1872 /* 1873 * If the interface is already up, we need 1874 * to re-init it in order to reprogram its 1875 * address filter. 1876 */ 1877 if ((ifp->if_flags & IFF_UP) != 0) { 1878 IFF_LOCKGIANT(ifp); 1879 ifp->if_flags &= ~IFF_UP; 1880 ifr.ifr_flags = ifp->if_flags & 0xffff; 1881 ifr.ifr_flagshigh = ifp->if_flags >> 16; 1882 (*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr); 1883 ifp->if_flags |= IFF_UP; 1884 ifr.ifr_flags = ifp->if_flags & 0xffff; 1885 ifr.ifr_flagshigh = ifp->if_flags >> 16; 1886 (*ifp->if_ioctl)(ifp, SIOCSIFFLAGS, (caddr_t)&ifr); 1887 IFF_UNLOCKGIANT(ifp); 1888 #ifdef INET 1889 /* 1890 * Also send gratuitous ARPs to notify other nodes about 1891 * the address change. 1892 */ 1893 TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 1894 if (ifa->ifa_addr != NULL && 1895 ifa->ifa_addr->sa_family == AF_INET) 1896 arp_ifinit(ifp, ifa); 1897 } 1898 #endif 1899 } 1900 return (0); 1901 } 1902 1903 struct ifmultiaddr * 1904 ifmaof_ifpforaddr(struct sockaddr *sa, struct ifnet *ifp) 1905 { 1906 struct ifmultiaddr *ifma; 1907 1908 TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) 1909 if (equal(ifma->ifma_addr, sa)) 1910 break; 1911 1912 return ifma; 1913 } 1914 1915 /* 1916 * The name argument must be a pointer to storage which will last as 1917 * long as the interface does. For physical devices, the result of 1918 * device_get_name(dev) is a good choice and for pseudo-devices a 1919 * static string works well. 1920 */ 1921 void 1922 if_initname(struct ifnet *ifp, const char *name, int unit) 1923 { 1924 ifp->if_dname = name; 1925 ifp->if_dunit = unit; 1926 if (unit != IF_DUNIT_NONE) 1927 snprintf(ifp->if_xname, IFNAMSIZ, "%s%d", name, unit); 1928 else 1929 strlcpy(ifp->if_xname, name, IFNAMSIZ); 1930 } 1931 1932 int 1933 if_printf(struct ifnet *ifp, const char * fmt, ...) 1934 { 1935 va_list ap; 1936 int retval; 1937 1938 retval = printf("%s: ", ifp->if_xname); 1939 va_start(ap, fmt); 1940 retval += vprintf(fmt, ap); 1941 va_end(ap); 1942 return (retval); 1943 } 1944 1945 /* 1946 * When an interface is marked IFF_NEEDSGIANT, its if_start() routine cannot 1947 * be called without Giant. However, we often can't acquire the Giant lock 1948 * at those points; instead, we run it via a task queue that holds Giant via 1949 * if_start_deferred. 1950 * 1951 * XXXRW: We need to make sure that the ifnet isn't fully detached until any 1952 * outstanding if_start_deferred() tasks that will run after the free. This 1953 * probably means waiting in if_detach(). 1954 */ 1955 void 1956 if_start(struct ifnet *ifp) 1957 { 1958 1959 NET_ASSERT_GIANT(); 1960 1961 if ((ifp->if_flags & IFF_NEEDSGIANT) != 0 && debug_mpsafenet != 0) { 1962 if (mtx_owned(&Giant)) 1963 (*(ifp)->if_start)(ifp); 1964 else 1965 taskqueue_enqueue(taskqueue_swi_giant, 1966 &ifp->if_starttask); 1967 } else 1968 (*(ifp)->if_start)(ifp); 1969 } 1970 1971 static void 1972 if_start_deferred(void *context, int pending) 1973 { 1974 struct ifnet *ifp; 1975 1976 /* 1977 * This code must be entered with Giant, and should never run if 1978 * we're not running with debug.mpsafenet. 1979 */ 1980 KASSERT(debug_mpsafenet != 0, ("if_start_deferred: debug.mpsafenet")); 1981 GIANT_REQUIRED; 1982 1983 ifp = (struct ifnet *)context; 1984 (ifp->if_start)(ifp); 1985 } 1986 1987 int 1988 if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust) 1989 { 1990 int active = 0; 1991 1992 IF_LOCK(ifq); 1993 if (_IF_QFULL(ifq)) { 1994 _IF_DROP(ifq); 1995 IF_UNLOCK(ifq); 1996 m_freem(m); 1997 return (0); 1998 } 1999 if (ifp != NULL) { 2000 ifp->if_obytes += m->m_pkthdr.len + adjust; 2001 if (m->m_flags & (M_BCAST|M_MCAST)) 2002 ifp->if_omcasts++; 2003 active = ifp->if_flags & IFF_OACTIVE; 2004 } 2005 _IF_ENQUEUE(ifq, m); 2006 IF_UNLOCK(ifq); 2007 if (ifp != NULL && !active) 2008 if_start(ifp); 2009 return (1); 2010 } 2011 2012 SYSCTL_NODE(_net, PF_LINK, link, CTLFLAG_RW, 0, "Link layers"); 2013 SYSCTL_NODE(_net_link, 0, generic, CTLFLAG_RW, 0, "Generic link-management"); 2014