1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * Copyright (C) 2001 WIDE Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)in.c 8.4 (Berkeley) 1/9/95 33 */ 34 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include "opt_inet.h" 39 40 #define IN_HISTORICAL_NETS /* include class masks */ 41 42 #include <sys/param.h> 43 #include <sys/eventhandler.h> 44 #include <sys/systm.h> 45 #include <sys/sockio.h> 46 #include <sys/malloc.h> 47 #include <sys/priv.h> 48 #include <sys/socket.h> 49 #include <sys/jail.h> 50 #include <sys/kernel.h> 51 #include <sys/lock.h> 52 #include <sys/proc.h> 53 #include <sys/sysctl.h> 54 #include <sys/syslog.h> 55 #include <sys/sx.h> 56 57 #include <net/if.h> 58 #include <net/if_var.h> 59 #include <net/if_arp.h> 60 #include <net/if_dl.h> 61 #include <net/if_llatbl.h> 62 #include <net/if_types.h> 63 #include <net/route.h> 64 #include <net/route/nhop.h> 65 #include <net/route/route_ctl.h> 66 #include <net/vnet.h> 67 68 #include <netinet/if_ether.h> 69 #include <netinet/in.h> 70 #include <netinet/in_fib.h> 71 #include <netinet/in_var.h> 72 #include <netinet/in_pcb.h> 73 #include <netinet/ip_var.h> 74 #include <netinet/ip_carp.h> 75 #include <netinet/igmp_var.h> 76 #include <netinet/udp.h> 77 #include <netinet/udp_var.h> 78 79 static int in_aifaddr_ioctl(u_long, caddr_t, struct ifnet *, struct thread *); 80 static int in_difaddr_ioctl(u_long, caddr_t, struct ifnet *, struct thread *); 81 static int in_gifaddr_ioctl(u_long, caddr_t, struct ifnet *, struct thread *); 82 83 static void in_socktrim(struct sockaddr_in *); 84 static void in_purgemaddrs(struct ifnet *); 85 86 static bool ia_need_loopback_route(const struct in_ifaddr *); 87 88 VNET_DEFINE_STATIC(int, nosameprefix); 89 #define V_nosameprefix VNET(nosameprefix) 90 SYSCTL_INT(_net_inet_ip, OID_AUTO, no_same_prefix, CTLFLAG_VNET | CTLFLAG_RW, 91 &VNET_NAME(nosameprefix), 0, 92 "Refuse to create same prefixes on different interfaces"); 93 94 VNET_DEFINE_STATIC(bool, broadcast_lowest); 95 #define V_broadcast_lowest VNET(broadcast_lowest) 96 SYSCTL_BOOL(_net_inet_ip, OID_AUTO, broadcast_lowest, CTLFLAG_VNET | CTLFLAG_RW, 97 &VNET_NAME(broadcast_lowest), 0, 98 "Treat lowest address on a subnet (host 0) as broadcast"); 99 100 VNET_DECLARE(struct inpcbinfo, ripcbinfo); 101 #define V_ripcbinfo VNET(ripcbinfo) 102 103 static struct sx in_control_sx; 104 SX_SYSINIT(in_control_sx, &in_control_sx, "in_control"); 105 106 /* 107 * Return 1 if an internet address is for a ``local'' host 108 * (one to which we have a connection). 109 */ 110 int 111 in_localaddr(struct in_addr in) 112 { 113 u_long i = ntohl(in.s_addr); 114 struct in_ifaddr *ia; 115 116 NET_EPOCH_ASSERT(); 117 118 CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) { 119 if ((i & ia->ia_subnetmask) == ia->ia_subnet) 120 return (1); 121 } 122 123 return (0); 124 } 125 126 /* 127 * Return 1 if an internet address is for the local host and configured 128 * on one of its interfaces. 129 */ 130 bool 131 in_localip(struct in_addr in) 132 { 133 struct in_ifaddr *ia; 134 135 NET_EPOCH_ASSERT(); 136 137 CK_LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) 138 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr) 139 return (true); 140 141 return (false); 142 } 143 144 /* 145 * Like in_localip(), but FIB-aware. 146 */ 147 bool 148 in_localip_fib(struct in_addr in, uint16_t fib) 149 { 150 struct in_ifaddr *ia; 151 152 NET_EPOCH_ASSERT(); 153 154 CK_LIST_FOREACH(ia, INADDR_HASH(in.s_addr), ia_hash) 155 if (IA_SIN(ia)->sin_addr.s_addr == in.s_addr && 156 ia->ia_ifa.ifa_ifp->if_fib == fib) 157 return (true); 158 159 return (false); 160 } 161 162 /* 163 * Return 1 if an internet address is configured on an interface. 164 */ 165 int 166 in_ifhasaddr(struct ifnet *ifp, struct in_addr in) 167 { 168 struct ifaddr *ifa; 169 struct in_ifaddr *ia; 170 171 NET_EPOCH_ASSERT(); 172 173 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 174 if (ifa->ifa_addr->sa_family != AF_INET) 175 continue; 176 ia = (struct in_ifaddr *)ifa; 177 if (ia->ia_addr.sin_addr.s_addr == in.s_addr) 178 return (1); 179 } 180 181 return (0); 182 } 183 184 /* 185 * Return a reference to the interface address which is different to 186 * the supplied one but with same IP address value. 187 */ 188 static struct in_ifaddr * 189 in_localip_more(struct in_ifaddr *original_ia) 190 { 191 struct epoch_tracker et; 192 in_addr_t original_addr = IA_SIN(original_ia)->sin_addr.s_addr; 193 uint32_t original_fib = original_ia->ia_ifa.ifa_ifp->if_fib; 194 struct in_ifaddr *ia; 195 196 NET_EPOCH_ENTER(et); 197 CK_LIST_FOREACH(ia, INADDR_HASH(original_addr), ia_hash) { 198 in_addr_t addr = IA_SIN(ia)->sin_addr.s_addr; 199 uint32_t fib = ia->ia_ifa.ifa_ifp->if_fib; 200 if (!V_rt_add_addr_allfibs && (original_fib != fib)) 201 continue; 202 if ((original_ia != ia) && (original_addr == addr)) { 203 ifa_ref(&ia->ia_ifa); 204 NET_EPOCH_EXIT(et); 205 return (ia); 206 } 207 } 208 NET_EPOCH_EXIT(et); 209 210 return (NULL); 211 } 212 213 /* 214 * Tries to find first IPv4 address in the provided fib. 215 * Prefers non-loopback addresses and return loopback IFF 216 * @loopback_ok is set. 217 * 218 * Returns ifa or NULL. 219 */ 220 struct in_ifaddr * 221 in_findlocal(uint32_t fibnum, bool loopback_ok) 222 { 223 struct in_ifaddr *ia = NULL, *ia_lo = NULL; 224 225 NET_EPOCH_ASSERT(); 226 227 CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) { 228 uint32_t ia_fib = ia->ia_ifa.ifa_ifp->if_fib; 229 if (!V_rt_add_addr_allfibs && (fibnum != ia_fib)) 230 continue; 231 232 if (!IN_LOOPBACK(ntohl(IA_SIN(ia)->sin_addr.s_addr))) 233 break; 234 if (loopback_ok) 235 ia_lo = ia; 236 } 237 238 if (ia == NULL) 239 ia = ia_lo; 240 241 return (ia); 242 } 243 244 /* 245 * Determine whether an IP address is in a reserved set of addresses 246 * that may not be forwarded, or whether datagrams to that destination 247 * may be forwarded. 248 */ 249 int 250 in_canforward(struct in_addr in) 251 { 252 u_long i = ntohl(in.s_addr); 253 254 if (IN_EXPERIMENTAL(i) || IN_MULTICAST(i) || IN_LINKLOCAL(i) || 255 IN_ZERONET(i) || IN_LOOPBACK(i)) 256 return (0); 257 return (1); 258 } 259 260 /* 261 * Trim a mask in a sockaddr 262 */ 263 static void 264 in_socktrim(struct sockaddr_in *ap) 265 { 266 char *cplim = (char *) &ap->sin_addr; 267 char *cp = (char *) (&ap->sin_addr + 1); 268 269 ap->sin_len = 0; 270 while (--cp >= cplim) 271 if (*cp) { 272 (ap)->sin_len = cp - (char *) (ap) + 1; 273 break; 274 } 275 } 276 277 /* 278 * Generic internet control operations (ioctl's). 279 */ 280 int 281 in_control(struct socket *so, u_long cmd, caddr_t data, struct ifnet *ifp, 282 struct thread *td) 283 { 284 struct ifreq *ifr = (struct ifreq *)data; 285 struct sockaddr_in *addr = (struct sockaddr_in *)&ifr->ifr_addr; 286 struct epoch_tracker et; 287 struct ifaddr *ifa; 288 struct in_ifaddr *ia; 289 int error; 290 291 if (ifp == NULL) 292 return (EADDRNOTAVAIL); 293 294 /* 295 * Filter out 4 ioctls we implement directly. Forward the rest 296 * to specific functions and ifp->if_ioctl(). 297 */ 298 switch (cmd) { 299 case SIOCGIFADDR: 300 case SIOCGIFBRDADDR: 301 case SIOCGIFDSTADDR: 302 case SIOCGIFNETMASK: 303 break; 304 case SIOCGIFALIAS: 305 sx_xlock(&in_control_sx); 306 error = in_gifaddr_ioctl(cmd, data, ifp, td); 307 sx_xunlock(&in_control_sx); 308 return (error); 309 case SIOCDIFADDR: 310 sx_xlock(&in_control_sx); 311 error = in_difaddr_ioctl(cmd, data, ifp, td); 312 sx_xunlock(&in_control_sx); 313 return (error); 314 case OSIOCAIFADDR: /* 9.x compat */ 315 case SIOCAIFADDR: 316 sx_xlock(&in_control_sx); 317 error = in_aifaddr_ioctl(cmd, data, ifp, td); 318 sx_xunlock(&in_control_sx); 319 return (error); 320 case SIOCSIFADDR: 321 case SIOCSIFBRDADDR: 322 case SIOCSIFDSTADDR: 323 case SIOCSIFNETMASK: 324 /* We no longer support that old commands. */ 325 return (EINVAL); 326 default: 327 if (ifp->if_ioctl == NULL) 328 return (EOPNOTSUPP); 329 return ((*ifp->if_ioctl)(ifp, cmd, data)); 330 } 331 332 if (addr->sin_addr.s_addr != INADDR_ANY && 333 prison_check_ip4(td->td_ucred, &addr->sin_addr) != 0) 334 return (EADDRNOTAVAIL); 335 336 /* 337 * Find address for this interface, if it exists. If an 338 * address was specified, find that one instead of the 339 * first one on the interface, if possible. 340 */ 341 NET_EPOCH_ENTER(et); 342 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 343 if (ifa->ifa_addr->sa_family != AF_INET) 344 continue; 345 ia = (struct in_ifaddr *)ifa; 346 if (ia->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr) 347 break; 348 } 349 if (ifa == NULL) 350 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 351 if (ifa->ifa_addr->sa_family == AF_INET) { 352 ia = (struct in_ifaddr *)ifa; 353 if (prison_check_ip4(td->td_ucred, 354 &ia->ia_addr.sin_addr) == 0) 355 break; 356 } 357 358 if (ifa == NULL) { 359 NET_EPOCH_EXIT(et); 360 return (EADDRNOTAVAIL); 361 } 362 363 error = 0; 364 switch (cmd) { 365 case SIOCGIFADDR: 366 *addr = ia->ia_addr; 367 break; 368 369 case SIOCGIFBRDADDR: 370 if ((ifp->if_flags & IFF_BROADCAST) == 0) { 371 error = EINVAL; 372 break; 373 } 374 *addr = ia->ia_broadaddr; 375 break; 376 377 case SIOCGIFDSTADDR: 378 if ((ifp->if_flags & IFF_POINTOPOINT) == 0) { 379 error = EINVAL; 380 break; 381 } 382 *addr = ia->ia_dstaddr; 383 break; 384 385 case SIOCGIFNETMASK: 386 *addr = ia->ia_sockmask; 387 break; 388 } 389 390 NET_EPOCH_EXIT(et); 391 392 return (error); 393 } 394 395 static int 396 in_aifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td) 397 { 398 const struct in_aliasreq *ifra = (struct in_aliasreq *)data; 399 const struct sockaddr_in *addr = &ifra->ifra_addr; 400 const struct sockaddr_in *broadaddr = &ifra->ifra_broadaddr; 401 const struct sockaddr_in *mask = &ifra->ifra_mask; 402 const struct sockaddr_in *dstaddr = &ifra->ifra_dstaddr; 403 const int vhid = (cmd == SIOCAIFADDR) ? ifra->ifra_vhid : 0; 404 struct epoch_tracker et; 405 struct ifaddr *ifa; 406 struct in_ifaddr *ia; 407 bool iaIsFirst; 408 int error = 0; 409 410 error = priv_check(td, PRIV_NET_ADDIFADDR); 411 if (error) 412 return (error); 413 414 /* 415 * ifra_addr must be present and be of INET family. 416 * ifra_broadaddr/ifra_dstaddr and ifra_mask are optional. 417 */ 418 if (addr->sin_len != sizeof(struct sockaddr_in) || 419 addr->sin_family != AF_INET) 420 return (EINVAL); 421 if (broadaddr->sin_len != 0 && 422 (broadaddr->sin_len != sizeof(struct sockaddr_in) || 423 broadaddr->sin_family != AF_INET)) 424 return (EINVAL); 425 if (mask->sin_len != 0 && 426 (mask->sin_len != sizeof(struct sockaddr_in) || 427 mask->sin_family != AF_INET)) 428 return (EINVAL); 429 if ((ifp->if_flags & IFF_POINTOPOINT) && 430 (dstaddr->sin_len != sizeof(struct sockaddr_in) || 431 dstaddr->sin_addr.s_addr == INADDR_ANY)) 432 return (EDESTADDRREQ); 433 if (vhid != 0 && carp_attach_p == NULL) 434 return (EPROTONOSUPPORT); 435 436 /* 437 * See whether address already exist. 438 */ 439 iaIsFirst = true; 440 ia = NULL; 441 NET_EPOCH_ENTER(et); 442 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 443 struct in_ifaddr *it; 444 445 if (ifa->ifa_addr->sa_family != AF_INET) 446 continue; 447 448 it = (struct in_ifaddr *)ifa; 449 if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr && 450 prison_check_ip4(td->td_ucred, &addr->sin_addr) == 0) 451 ia = it; 452 else 453 iaIsFirst = false; 454 } 455 NET_EPOCH_EXIT(et); 456 457 if (ia != NULL) 458 (void )in_difaddr_ioctl(cmd, data, ifp, td); 459 460 ifa = ifa_alloc(sizeof(struct in_ifaddr), M_WAITOK); 461 ia = (struct in_ifaddr *)ifa; 462 ifa->ifa_addr = (struct sockaddr *)&ia->ia_addr; 463 ifa->ifa_dstaddr = (struct sockaddr *)&ia->ia_dstaddr; 464 ifa->ifa_netmask = (struct sockaddr *)&ia->ia_sockmask; 465 callout_init_rw(&ia->ia_garp_timer, &ifp->if_addr_lock, 466 CALLOUT_RETURNUNLOCKED); 467 468 ia->ia_ifp = ifp; 469 ia->ia_addr = *addr; 470 if (mask->sin_len != 0) { 471 ia->ia_sockmask = *mask; 472 ia->ia_subnetmask = ntohl(ia->ia_sockmask.sin_addr.s_addr); 473 } else { 474 in_addr_t i = ntohl(addr->sin_addr.s_addr); 475 476 /* 477 * If netmask isn't supplied, use historical default. 478 * This is deprecated for interfaces other than loopback 479 * or point-to-point; warn in other cases. In the future 480 * we should return an error rather than warning. 481 */ 482 if ((ifp->if_flags & (IFF_POINTOPOINT | IFF_LOOPBACK)) == 0) 483 printf("%s: set address: WARNING: network mask " 484 "should be specified; using historical default\n", 485 ifp->if_xname); 486 if (IN_CLASSA(i)) 487 ia->ia_subnetmask = IN_CLASSA_NET; 488 else if (IN_CLASSB(i)) 489 ia->ia_subnetmask = IN_CLASSB_NET; 490 else 491 ia->ia_subnetmask = IN_CLASSC_NET; 492 ia->ia_sockmask.sin_addr.s_addr = htonl(ia->ia_subnetmask); 493 } 494 ia->ia_subnet = ntohl(addr->sin_addr.s_addr) & ia->ia_subnetmask; 495 in_socktrim(&ia->ia_sockmask); 496 497 if (ifp->if_flags & IFF_BROADCAST) { 498 if (broadaddr->sin_len != 0) { 499 ia->ia_broadaddr = *broadaddr; 500 } else if (ia->ia_subnetmask == IN_RFC3021_MASK) { 501 ia->ia_broadaddr.sin_addr.s_addr = INADDR_BROADCAST; 502 ia->ia_broadaddr.sin_len = sizeof(struct sockaddr_in); 503 ia->ia_broadaddr.sin_family = AF_INET; 504 } else { 505 ia->ia_broadaddr.sin_addr.s_addr = 506 htonl(ia->ia_subnet | ~ia->ia_subnetmask); 507 ia->ia_broadaddr.sin_len = sizeof(struct sockaddr_in); 508 ia->ia_broadaddr.sin_family = AF_INET; 509 } 510 } 511 512 if (ifp->if_flags & IFF_POINTOPOINT) 513 ia->ia_dstaddr = *dstaddr; 514 515 if (vhid != 0) { 516 error = (*carp_attach_p)(&ia->ia_ifa, vhid); 517 if (error) 518 return (error); 519 } 520 521 /* if_addrhead is already referenced by ifa_alloc() */ 522 IF_ADDR_WLOCK(ifp); 523 CK_STAILQ_INSERT_TAIL(&ifp->if_addrhead, ifa, ifa_link); 524 IF_ADDR_WUNLOCK(ifp); 525 526 ifa_ref(ifa); /* in_ifaddrhead */ 527 sx_assert(&in_control_sx, SA_XLOCKED); 528 CK_STAILQ_INSERT_TAIL(&V_in_ifaddrhead, ia, ia_link); 529 CK_LIST_INSERT_HEAD(INADDR_HASH(ia->ia_addr.sin_addr.s_addr), ia, 530 ia_hash); 531 532 /* 533 * Give the interface a chance to initialize 534 * if this is its first address, 535 * and to validate the address if necessary. 536 */ 537 if (ifp->if_ioctl != NULL) { 538 error = (*ifp->if_ioctl)(ifp, SIOCSIFADDR, (caddr_t)ia); 539 if (error) 540 goto fail1; 541 } 542 543 /* 544 * Add route for the network. 545 */ 546 if (vhid == 0) { 547 error = in_addprefix(ia); 548 if (error) 549 goto fail1; 550 } 551 552 /* 553 * Add a loopback route to self. 554 */ 555 if (vhid == 0 && ia_need_loopback_route(ia)) { 556 struct in_ifaddr *eia; 557 558 eia = in_localip_more(ia); 559 560 if (eia == NULL) { 561 error = ifa_add_loopback_route((struct ifaddr *)ia, 562 (struct sockaddr *)&ia->ia_addr); 563 if (error) 564 goto fail2; 565 } else 566 ifa_free(&eia->ia_ifa); 567 } 568 569 if (iaIsFirst && (ifp->if_flags & IFF_MULTICAST)) { 570 struct in_addr allhosts_addr; 571 struct in_ifinfo *ii; 572 573 ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]); 574 allhosts_addr.s_addr = htonl(INADDR_ALLHOSTS_GROUP); 575 576 error = in_joingroup(ifp, &allhosts_addr, NULL, 577 &ii->ii_allhosts); 578 } 579 580 /* 581 * Note: we don't need extra reference for ifa, since we called 582 * with sx lock held, and ifaddr can not be deleted in concurrent 583 * thread. 584 */ 585 EVENTHANDLER_INVOKE(ifaddr_event_ext, ifp, ifa, IFADDR_EVENT_ADD); 586 587 return (error); 588 589 fail2: 590 if (vhid == 0) 591 (void )in_scrubprefix(ia, LLE_STATIC); 592 593 fail1: 594 if (ia->ia_ifa.ifa_carp) 595 (*carp_detach_p)(&ia->ia_ifa, false); 596 597 IF_ADDR_WLOCK(ifp); 598 CK_STAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifaddr, ifa_link); 599 IF_ADDR_WUNLOCK(ifp); 600 ifa_free(&ia->ia_ifa); /* if_addrhead */ 601 602 sx_assert(&in_control_sx, SA_XLOCKED); 603 CK_STAILQ_REMOVE(&V_in_ifaddrhead, ia, in_ifaddr, ia_link); 604 CK_LIST_REMOVE(ia, ia_hash); 605 ifa_free(&ia->ia_ifa); /* in_ifaddrhead */ 606 607 return (error); 608 } 609 610 static int 611 in_difaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td) 612 { 613 const struct ifreq *ifr = (struct ifreq *)data; 614 const struct sockaddr_in *addr = (const struct sockaddr_in *) 615 &ifr->ifr_addr; 616 struct ifaddr *ifa; 617 struct in_ifaddr *ia; 618 bool deleteAny, iaIsLast; 619 int error; 620 621 if (td != NULL) { 622 error = priv_check(td, PRIV_NET_DELIFADDR); 623 if (error) 624 return (error); 625 } 626 627 if (addr->sin_len != sizeof(struct sockaddr_in) || 628 addr->sin_family != AF_INET) 629 deleteAny = true; 630 else 631 deleteAny = false; 632 633 iaIsLast = true; 634 ia = NULL; 635 IF_ADDR_WLOCK(ifp); 636 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 637 struct in_ifaddr *it; 638 639 if (ifa->ifa_addr->sa_family != AF_INET) 640 continue; 641 642 it = (struct in_ifaddr *)ifa; 643 if (deleteAny && ia == NULL && (td == NULL || 644 prison_check_ip4(td->td_ucred, &it->ia_addr.sin_addr) == 0)) 645 ia = it; 646 647 if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr && 648 (td == NULL || prison_check_ip4(td->td_ucred, 649 &addr->sin_addr) == 0)) 650 ia = it; 651 652 if (it != ia) 653 iaIsLast = false; 654 } 655 656 if (ia == NULL) { 657 IF_ADDR_WUNLOCK(ifp); 658 return (EADDRNOTAVAIL); 659 } 660 661 CK_STAILQ_REMOVE(&ifp->if_addrhead, &ia->ia_ifa, ifaddr, ifa_link); 662 IF_ADDR_WUNLOCK(ifp); 663 ifa_free(&ia->ia_ifa); /* if_addrhead */ 664 665 sx_assert(&in_control_sx, SA_XLOCKED); 666 CK_STAILQ_REMOVE(&V_in_ifaddrhead, ia, in_ifaddr, ia_link); 667 CK_LIST_REMOVE(ia, ia_hash); 668 669 /* 670 * in_scrubprefix() kills the interface route. 671 */ 672 in_scrubprefix(ia, LLE_STATIC); 673 674 /* 675 * in_ifadown gets rid of all the rest of 676 * the routes. This is not quite the right 677 * thing to do, but at least if we are running 678 * a routing process they will come back. 679 */ 680 in_ifadown(&ia->ia_ifa, 1); 681 682 if (ia->ia_ifa.ifa_carp) 683 (*carp_detach_p)(&ia->ia_ifa, cmd == SIOCAIFADDR); 684 685 /* 686 * If this is the last IPv4 address configured on this 687 * interface, leave the all-hosts group. 688 * No state-change report need be transmitted. 689 */ 690 if (iaIsLast && (ifp->if_flags & IFF_MULTICAST)) { 691 struct in_ifinfo *ii; 692 693 ii = ((struct in_ifinfo *)ifp->if_afdata[AF_INET]); 694 if (ii->ii_allhosts) { 695 (void)in_leavegroup(ii->ii_allhosts, NULL); 696 ii->ii_allhosts = NULL; 697 } 698 } 699 700 IF_ADDR_WLOCK(ifp); 701 if (callout_stop(&ia->ia_garp_timer) == 1) { 702 ifa_free(&ia->ia_ifa); 703 } 704 IF_ADDR_WUNLOCK(ifp); 705 706 EVENTHANDLER_INVOKE(ifaddr_event_ext, ifp, &ia->ia_ifa, 707 IFADDR_EVENT_DEL); 708 ifa_free(&ia->ia_ifa); /* in_ifaddrhead */ 709 710 return (0); 711 } 712 713 static int 714 in_gifaddr_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp, struct thread *td) 715 { 716 struct in_aliasreq *ifra = (struct in_aliasreq *)data; 717 const struct sockaddr_in *addr = &ifra->ifra_addr; 718 struct epoch_tracker et; 719 struct ifaddr *ifa; 720 struct in_ifaddr *ia; 721 722 /* 723 * ifra_addr must be present and be of INET family. 724 */ 725 if (addr->sin_len != sizeof(struct sockaddr_in) || 726 addr->sin_family != AF_INET) 727 return (EINVAL); 728 729 /* 730 * See whether address exist. 731 */ 732 ia = NULL; 733 NET_EPOCH_ENTER(et); 734 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) { 735 struct in_ifaddr *it; 736 737 if (ifa->ifa_addr->sa_family != AF_INET) 738 continue; 739 740 it = (struct in_ifaddr *)ifa; 741 if (it->ia_addr.sin_addr.s_addr == addr->sin_addr.s_addr && 742 prison_check_ip4(td->td_ucred, &addr->sin_addr) == 0) { 743 ia = it; 744 break; 745 } 746 } 747 if (ia == NULL) { 748 NET_EPOCH_EXIT(et); 749 return (EADDRNOTAVAIL); 750 } 751 752 ifra->ifra_mask = ia->ia_sockmask; 753 if ((ifp->if_flags & IFF_POINTOPOINT) && 754 ia->ia_dstaddr.sin_family == AF_INET) 755 ifra->ifra_dstaddr = ia->ia_dstaddr; 756 else if ((ifp->if_flags & IFF_BROADCAST) && 757 ia->ia_broadaddr.sin_family == AF_INET) 758 ifra->ifra_broadaddr = ia->ia_broadaddr; 759 else 760 memset(&ifra->ifra_broadaddr, 0, 761 sizeof(ifra->ifra_broadaddr)); 762 763 NET_EPOCH_EXIT(et); 764 return (0); 765 } 766 767 static int 768 in_match_ifaddr(const struct rtentry *rt, const struct nhop_object *nh, void *arg) 769 { 770 771 if (nh->nh_ifa == (struct ifaddr *)arg) 772 return (1); 773 774 return (0); 775 } 776 777 static int 778 in_handle_prefix_route(uint32_t fibnum, int cmd, 779 struct sockaddr_in *dst, struct sockaddr_in *netmask, struct ifaddr *ifa, 780 struct ifnet *ifp) 781 { 782 783 NET_EPOCH_ASSERT(); 784 785 /* Prepare gateway */ 786 struct sockaddr_dl_short sdl = { 787 .sdl_family = AF_LINK, 788 .sdl_len = sizeof(struct sockaddr_dl_short), 789 .sdl_type = ifa->ifa_ifp->if_type, 790 .sdl_index = ifa->ifa_ifp->if_index, 791 }; 792 793 struct rt_addrinfo info = { 794 .rti_ifa = ifa, 795 .rti_ifp = ifp, 796 .rti_flags = RTF_PINNED | ((netmask != NULL) ? 0 : RTF_HOST), 797 .rti_info = { 798 [RTAX_DST] = (struct sockaddr *)dst, 799 [RTAX_NETMASK] = (struct sockaddr *)netmask, 800 [RTAX_GATEWAY] = (struct sockaddr *)&sdl, 801 }, 802 /* Ensure we delete the prefix IFF prefix ifa matches */ 803 .rti_filter = in_match_ifaddr, 804 .rti_filterdata = ifa, 805 }; 806 807 return (rib_handle_ifaddr_info(fibnum, cmd, &info)); 808 } 809 810 /* 811 * Routing table interaction with interface addresses. 812 * 813 * In general, two types of routes needs to be installed: 814 * a) "interface" or "prefix" route, telling user that the addresses 815 * behind the ifa prefix are reached directly. 816 * b) "loopback" route installed for the ifa address, telling user that 817 * the address belongs to local system. 818 * 819 * Handling for (a) and (b) differs in multi-fib aspects, hence they 820 * are implemented in different functions below. 821 * 822 * The cases above may intersect - /32 interface aliases results in 823 * the same prefix produced by (a) and (b). This blurs the definition 824 * of the "loopback" route and complicate interactions. The interaction 825 * table is defined below. The case numbers are used in the multiple 826 * functions below to refer to the particular test case. 827 * 828 * There can be multiple options: 829 * 1) Adding address with prefix on non-p2p/non-loopback interface. 830 * Example: 192.0.2.1/24. Action: 831 * * add "prefix" route towards 192.0.2.0/24 via @ia interface, 832 * using @ia as an address source. 833 * * add "loopback" route towards 192.0.2.1 via V_loif, saving 834 * @ia ifp in the gateway and using @ia as an address source. 835 * 836 * 2) Adding address with /32 mask to non-p2p/non-loopback interface. 837 * Example: 192.0.2.2/32. Action: 838 * * add "prefix" host route via V_loif, using @ia as an address source. 839 * 840 * 3) Adding address with or without prefix to p2p interface. 841 * Example: 10.0.0.1/24->10.0.0.2. Action: 842 * * add "prefix" host route towards 10.0.0.2 via this interface, using @ia 843 * as an address source. Note: no sense in installing full /24 as the interface 844 * is point-to-point. 845 * * add "loopback" route towards 10.0.9.1 via V_loif, saving 846 * @ia ifp in the gateway and using @ia as an address source. 847 * 848 * 4) Adding address with or without prefix to loopback interface. 849 * Example: 192.0.2.1/24. Action: 850 * * add "prefix" host route via @ia interface, using @ia as an address source. 851 * Note: Skip installing /24 prefix as it would introduce TTL loop 852 * for the traffic destined to these addresses. 853 */ 854 855 /* 856 * Checks if @ia needs to install loopback route to @ia address via 857 * ifa_maintain_loopback_route(). 858 * 859 * Return true on success. 860 */ 861 static bool 862 ia_need_loopback_route(const struct in_ifaddr *ia) 863 { 864 struct ifnet *ifp = ia->ia_ifp; 865 866 /* Case 4: Skip loopback interfaces */ 867 if ((ifp->if_flags & IFF_LOOPBACK) || 868 (ia->ia_addr.sin_addr.s_addr == INADDR_ANY)) 869 return (false); 870 871 /* Clash avoidance: Skip p2p interfaces with both addresses are equal */ 872 if ((ifp->if_flags & IFF_POINTOPOINT) && 873 ia->ia_dstaddr.sin_addr.s_addr == ia->ia_addr.sin_addr.s_addr) 874 return (false); 875 876 /* Case 2: skip /32 prefixes */ 877 if (!(ifp->if_flags & IFF_POINTOPOINT) && 878 (ia->ia_sockmask.sin_addr.s_addr == INADDR_BROADCAST)) 879 return (false); 880 881 return (true); 882 } 883 884 /* 885 * Calculate "prefix" route corresponding to @ia. 886 */ 887 static void 888 ia_getrtprefix(const struct in_ifaddr *ia, struct in_addr *prefix, struct in_addr *mask) 889 { 890 891 if (ia->ia_ifp->if_flags & IFF_POINTOPOINT) { 892 /* Case 3: return host route for dstaddr */ 893 *prefix = ia->ia_dstaddr.sin_addr; 894 mask->s_addr = INADDR_BROADCAST; 895 } else if (ia->ia_ifp->if_flags & IFF_LOOPBACK) { 896 /* Case 4: return host route for ifaddr */ 897 *prefix = ia->ia_addr.sin_addr; 898 mask->s_addr = INADDR_BROADCAST; 899 } else { 900 /* Cases 1,2: return actual ia prefix */ 901 *prefix = ia->ia_addr.sin_addr; 902 *mask = ia->ia_sockmask.sin_addr; 903 prefix->s_addr &= mask->s_addr; 904 } 905 } 906 907 /* 908 * Adds or delete interface "prefix" route corresponding to @ifa. 909 * Returns 0 on success or errno. 910 */ 911 int 912 in_handle_ifaddr_route(int cmd, struct in_ifaddr *ia) 913 { 914 struct ifaddr *ifa = &ia->ia_ifa; 915 struct in_addr daddr, maddr; 916 struct sockaddr_in *pmask; 917 struct epoch_tracker et; 918 int error; 919 920 ia_getrtprefix(ia, &daddr, &maddr); 921 922 struct sockaddr_in mask = { 923 .sin_family = AF_INET, 924 .sin_len = sizeof(struct sockaddr_in), 925 .sin_addr = maddr, 926 }; 927 928 pmask = (maddr.s_addr != INADDR_BROADCAST) ? &mask : NULL; 929 930 struct sockaddr_in dst = { 931 .sin_family = AF_INET, 932 .sin_len = sizeof(struct sockaddr_in), 933 .sin_addr.s_addr = daddr.s_addr & maddr.s_addr, 934 }; 935 936 struct ifnet *ifp = ia->ia_ifp; 937 938 if ((maddr.s_addr == INADDR_BROADCAST) && 939 (!(ia->ia_ifp->if_flags & (IFF_POINTOPOINT|IFF_LOOPBACK)))) { 940 /* Case 2: host route on broadcast interface */ 941 ifp = V_loif; 942 } 943 944 uint32_t fibnum = ifa->ifa_ifp->if_fib; 945 NET_EPOCH_ENTER(et); 946 error = in_handle_prefix_route(fibnum, cmd, &dst, pmask, ifa, ifp); 947 NET_EPOCH_EXIT(et); 948 949 return (error); 950 } 951 952 /* 953 * Check if we have a route for the given prefix already. 954 */ 955 static bool 956 in_hasrtprefix(struct in_ifaddr *target) 957 { 958 struct epoch_tracker et; 959 struct in_ifaddr *ia; 960 struct in_addr prefix, mask, p, m; 961 bool result = false; 962 963 ia_getrtprefix(target, &prefix, &mask); 964 965 /* Look for an existing address with the same prefix, mask, and fib */ 966 NET_EPOCH_ENTER(et); 967 CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) { 968 ia_getrtprefix(ia, &p, &m); 969 970 if (prefix.s_addr != p.s_addr || 971 mask.s_addr != m.s_addr) 972 continue; 973 974 if (target->ia_ifp->if_fib != ia->ia_ifp->if_fib) 975 continue; 976 977 /* 978 * If we got a matching prefix route inserted by other 979 * interface address, we are done here. 980 */ 981 if (ia->ia_flags & IFA_ROUTE) { 982 result = true; 983 break; 984 } 985 } 986 NET_EPOCH_EXIT(et); 987 988 return (result); 989 } 990 991 int 992 in_addprefix(struct in_ifaddr *target) 993 { 994 int error; 995 996 if (in_hasrtprefix(target)) { 997 if (V_nosameprefix) 998 return (EEXIST); 999 else { 1000 rt_addrmsg(RTM_ADD, &target->ia_ifa, 1001 target->ia_ifp->if_fib); 1002 return (0); 1003 } 1004 } 1005 1006 /* 1007 * No-one seem to have this prefix route, so we try to insert it. 1008 */ 1009 rt_addrmsg(RTM_ADD, &target->ia_ifa, target->ia_ifp->if_fib); 1010 error = in_handle_ifaddr_route(RTM_ADD, target); 1011 if (!error) 1012 target->ia_flags |= IFA_ROUTE; 1013 return (error); 1014 } 1015 1016 /* 1017 * Removes either all lle entries for given @ia, or lle 1018 * corresponding to @ia address. 1019 */ 1020 static void 1021 in_scrubprefixlle(struct in_ifaddr *ia, int all, u_int flags) 1022 { 1023 struct sockaddr_in addr, mask; 1024 struct sockaddr *saddr, *smask; 1025 struct ifnet *ifp; 1026 1027 saddr = (struct sockaddr *)&addr; 1028 bzero(&addr, sizeof(addr)); 1029 addr.sin_len = sizeof(addr); 1030 addr.sin_family = AF_INET; 1031 smask = (struct sockaddr *)&mask; 1032 bzero(&mask, sizeof(mask)); 1033 mask.sin_len = sizeof(mask); 1034 mask.sin_family = AF_INET; 1035 mask.sin_addr.s_addr = ia->ia_subnetmask; 1036 ifp = ia->ia_ifp; 1037 1038 if (all) { 1039 /* 1040 * Remove all L2 entries matching given prefix. 1041 * Convert address to host representation to avoid 1042 * doing this on every callback. ia_subnetmask is already 1043 * stored in host representation. 1044 */ 1045 addr.sin_addr.s_addr = ntohl(ia->ia_addr.sin_addr.s_addr); 1046 lltable_prefix_free(AF_INET, saddr, smask, flags); 1047 } else { 1048 /* Remove interface address only */ 1049 addr.sin_addr.s_addr = ia->ia_addr.sin_addr.s_addr; 1050 lltable_delete_addr(LLTABLE(ifp), LLE_IFADDR, saddr); 1051 } 1052 } 1053 1054 /* 1055 * If there is no other address in the system that can serve a route to the 1056 * same prefix, remove the route. Hand over the route to the new address 1057 * otherwise. 1058 */ 1059 int 1060 in_scrubprefix(struct in_ifaddr *target, u_int flags) 1061 { 1062 struct epoch_tracker et; 1063 struct in_ifaddr *ia; 1064 struct in_addr prefix, mask, p, m; 1065 int error = 0; 1066 1067 /* 1068 * Remove the loopback route to the interface address. 1069 */ 1070 if (ia_need_loopback_route(target) && (flags & LLE_STATIC)) { 1071 struct in_ifaddr *eia; 1072 1073 eia = in_localip_more(target); 1074 1075 if (eia != NULL) { 1076 error = ifa_switch_loopback_route((struct ifaddr *)eia, 1077 (struct sockaddr *)&target->ia_addr); 1078 ifa_free(&eia->ia_ifa); 1079 } else { 1080 error = ifa_del_loopback_route((struct ifaddr *)target, 1081 (struct sockaddr *)&target->ia_addr); 1082 } 1083 } 1084 1085 ia_getrtprefix(target, &prefix, &mask); 1086 1087 if ((target->ia_flags & IFA_ROUTE) == 0) { 1088 rt_addrmsg(RTM_DELETE, &target->ia_ifa, target->ia_ifp->if_fib); 1089 1090 /* 1091 * Removing address from !IFF_UP interface or 1092 * prefix which exists on other interface (along with route). 1093 * No entries should exist here except target addr. 1094 * Given that, delete this entry only. 1095 */ 1096 in_scrubprefixlle(target, 0, flags); 1097 return (0); 1098 } 1099 1100 NET_EPOCH_ENTER(et); 1101 CK_STAILQ_FOREACH(ia, &V_in_ifaddrhead, ia_link) { 1102 ia_getrtprefix(ia, &p, &m); 1103 1104 if (prefix.s_addr != p.s_addr || 1105 mask.s_addr != m.s_addr) 1106 continue; 1107 1108 if ((ia->ia_ifp->if_flags & IFF_UP) == 0) 1109 continue; 1110 1111 /* 1112 * If we got a matching prefix address, move IFA_ROUTE and 1113 * the route itself to it. Make sure that routing daemons 1114 * get a heads-up. 1115 */ 1116 if ((ia->ia_flags & IFA_ROUTE) == 0) { 1117 ifa_ref(&ia->ia_ifa); 1118 NET_EPOCH_EXIT(et); 1119 error = in_handle_ifaddr_route(RTM_DELETE, target); 1120 if (error == 0) 1121 target->ia_flags &= ~IFA_ROUTE; 1122 else 1123 log(LOG_INFO, "in_scrubprefix: err=%d, old prefix delete failed\n", 1124 error); 1125 /* Scrub all entries IFF interface is different */ 1126 in_scrubprefixlle(target, target->ia_ifp != ia->ia_ifp, 1127 flags); 1128 error = in_handle_ifaddr_route(RTM_ADD, ia); 1129 if (error == 0) 1130 ia->ia_flags |= IFA_ROUTE; 1131 else 1132 log(LOG_INFO, "in_scrubprefix: err=%d, new prefix add failed\n", 1133 error); 1134 ifa_free(&ia->ia_ifa); 1135 return (error); 1136 } 1137 } 1138 NET_EPOCH_EXIT(et); 1139 1140 /* 1141 * remove all L2 entries on the given prefix 1142 */ 1143 in_scrubprefixlle(target, 1, flags); 1144 1145 /* 1146 * As no-one seem to have this prefix, we can remove the route. 1147 */ 1148 rt_addrmsg(RTM_DELETE, &target->ia_ifa, target->ia_ifp->if_fib); 1149 error = in_handle_ifaddr_route(RTM_DELETE, target); 1150 if (error == 0) 1151 target->ia_flags &= ~IFA_ROUTE; 1152 else 1153 log(LOG_INFO, "in_scrubprefix: err=%d, prefix delete failed\n", error); 1154 return (error); 1155 } 1156 1157 void 1158 in_ifscrub_all(void) 1159 { 1160 struct ifnet *ifp; 1161 struct ifaddr *ifa, *nifa; 1162 struct ifaliasreq ifr; 1163 1164 IFNET_RLOCK(); 1165 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) { 1166 /* Cannot lock here - lock recursion. */ 1167 /* NET_EPOCH_ENTER(et); */ 1168 CK_STAILQ_FOREACH_SAFE(ifa, &ifp->if_addrhead, ifa_link, nifa) { 1169 if (ifa->ifa_addr->sa_family != AF_INET) 1170 continue; 1171 1172 /* 1173 * This is ugly but the only way for legacy IP to 1174 * cleanly remove addresses and everything attached. 1175 */ 1176 bzero(&ifr, sizeof(ifr)); 1177 ifr.ifra_addr = *ifa->ifa_addr; 1178 if (ifa->ifa_dstaddr) 1179 ifr.ifra_broadaddr = *ifa->ifa_dstaddr; 1180 (void)in_control(NULL, SIOCDIFADDR, (caddr_t)&ifr, 1181 ifp, NULL); 1182 } 1183 /* NET_EPOCH_EXIT(et); */ 1184 in_purgemaddrs(ifp); 1185 igmp_domifdetach(ifp); 1186 } 1187 IFNET_RUNLOCK(); 1188 } 1189 1190 int 1191 in_ifaddr_broadcast(struct in_addr in, struct in_ifaddr *ia) 1192 { 1193 1194 return ((in.s_addr == ia->ia_broadaddr.sin_addr.s_addr || 1195 /* 1196 * Optionally check for old-style (host 0) broadcast, but 1197 * taking into account that RFC 3021 obsoletes it. 1198 */ 1199 (V_broadcast_lowest && ia->ia_subnetmask != IN_RFC3021_MASK && 1200 ntohl(in.s_addr) == ia->ia_subnet)) && 1201 /* 1202 * Check for an all one subnetmask. These 1203 * only exist when an interface gets a secondary 1204 * address. 1205 */ 1206 ia->ia_subnetmask != (u_long)0xffffffff); 1207 } 1208 1209 /* 1210 * Return 1 if the address might be a local broadcast address. 1211 */ 1212 int 1213 in_broadcast(struct in_addr in, struct ifnet *ifp) 1214 { 1215 struct ifaddr *ifa; 1216 int found; 1217 1218 NET_EPOCH_ASSERT(); 1219 1220 if (in.s_addr == INADDR_BROADCAST || 1221 in.s_addr == INADDR_ANY) 1222 return (1); 1223 if ((ifp->if_flags & IFF_BROADCAST) == 0) 1224 return (0); 1225 found = 0; 1226 /* 1227 * Look through the list of addresses for a match 1228 * with a broadcast address. 1229 */ 1230 CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) 1231 if (ifa->ifa_addr->sa_family == AF_INET && 1232 in_ifaddr_broadcast(in, (struct in_ifaddr *)ifa)) { 1233 found = 1; 1234 break; 1235 } 1236 return (found); 1237 } 1238 1239 /* 1240 * On interface removal, clean up IPv4 data structures hung off of the ifnet. 1241 */ 1242 void 1243 in_ifdetach(struct ifnet *ifp) 1244 { 1245 IN_MULTI_LOCK(); 1246 in_pcbpurgeif0(&V_ripcbinfo, ifp); 1247 in_pcbpurgeif0(&V_udbinfo, ifp); 1248 in_pcbpurgeif0(&V_ulitecbinfo, ifp); 1249 in_purgemaddrs(ifp); 1250 IN_MULTI_UNLOCK(); 1251 1252 /* 1253 * Make sure all multicast deletions invoking if_ioctl() are 1254 * completed before returning. Else we risk accessing a freed 1255 * ifnet structure pointer. 1256 */ 1257 inm_release_wait(NULL); 1258 } 1259 1260 /* 1261 * Delete all IPv4 multicast address records, and associated link-layer 1262 * multicast address records, associated with ifp. 1263 * XXX It looks like domifdetach runs AFTER the link layer cleanup. 1264 * XXX This should not race with ifma_protospec being set during 1265 * a new allocation, if it does, we have bigger problems. 1266 */ 1267 static void 1268 in_purgemaddrs(struct ifnet *ifp) 1269 { 1270 struct in_multi_head purgeinms; 1271 struct in_multi *inm; 1272 struct ifmultiaddr *ifma, *next; 1273 1274 SLIST_INIT(&purgeinms); 1275 IN_MULTI_LIST_LOCK(); 1276 1277 /* 1278 * Extract list of in_multi associated with the detaching ifp 1279 * which the PF_INET layer is about to release. 1280 * We need to do this as IF_ADDR_LOCK() may be re-acquired 1281 * by code further down. 1282 */ 1283 IF_ADDR_WLOCK(ifp); 1284 restart: 1285 CK_STAILQ_FOREACH_SAFE(ifma, &ifp->if_multiaddrs, ifma_link, next) { 1286 if (ifma->ifma_addr->sa_family != AF_INET || 1287 ifma->ifma_protospec == NULL) 1288 continue; 1289 inm = (struct in_multi *)ifma->ifma_protospec; 1290 inm_rele_locked(&purgeinms, inm); 1291 if (__predict_false(ifma_restart)) { 1292 ifma_restart = true; 1293 goto restart; 1294 } 1295 } 1296 IF_ADDR_WUNLOCK(ifp); 1297 1298 inm_release_list_deferred(&purgeinms); 1299 igmp_ifdetach(ifp); 1300 IN_MULTI_LIST_UNLOCK(); 1301 } 1302 1303 struct in_llentry { 1304 struct llentry base; 1305 }; 1306 1307 #define IN_LLTBL_DEFAULT_HSIZE 32 1308 #define IN_LLTBL_HASH(k, h) \ 1309 (((((((k >> 8) ^ k) >> 8) ^ k) >> 8) ^ k) & ((h) - 1)) 1310 1311 /* 1312 * Do actual deallocation of @lle. 1313 */ 1314 static void 1315 in_lltable_destroy_lle_unlocked(epoch_context_t ctx) 1316 { 1317 struct llentry *lle; 1318 1319 lle = __containerof(ctx, struct llentry, lle_epoch_ctx); 1320 LLE_LOCK_DESTROY(lle); 1321 LLE_REQ_DESTROY(lle); 1322 free(lle, M_LLTABLE); 1323 } 1324 1325 /* 1326 * Called by LLE_FREE_LOCKED when number of references 1327 * drops to zero. 1328 */ 1329 static void 1330 in_lltable_destroy_lle(struct llentry *lle) 1331 { 1332 1333 LLE_WUNLOCK(lle); 1334 NET_EPOCH_CALL(in_lltable_destroy_lle_unlocked, &lle->lle_epoch_ctx); 1335 } 1336 1337 static struct llentry * 1338 in_lltable_new(struct in_addr addr4, u_int flags) 1339 { 1340 struct in_llentry *lle; 1341 1342 lle = malloc(sizeof(struct in_llentry), M_LLTABLE, M_NOWAIT | M_ZERO); 1343 if (lle == NULL) /* NB: caller generates msg */ 1344 return NULL; 1345 1346 /* 1347 * For IPv4 this will trigger "arpresolve" to generate 1348 * an ARP request. 1349 */ 1350 lle->base.la_expire = time_uptime; /* mark expired */ 1351 lle->base.r_l3addr.addr4 = addr4; 1352 lle->base.lle_refcnt = 1; 1353 lle->base.lle_free = in_lltable_destroy_lle; 1354 LLE_LOCK_INIT(&lle->base); 1355 LLE_REQ_INIT(&lle->base); 1356 callout_init(&lle->base.lle_timer, 1); 1357 1358 return (&lle->base); 1359 } 1360 1361 #define IN_ARE_MASKED_ADDR_EQUAL(d, a, m) ( \ 1362 ((((d).s_addr ^ (a).s_addr) & (m).s_addr)) == 0 ) 1363 1364 static int 1365 in_lltable_match_prefix(const struct sockaddr *saddr, 1366 const struct sockaddr *smask, u_int flags, struct llentry *lle) 1367 { 1368 struct in_addr addr, mask, lle_addr; 1369 1370 addr = ((const struct sockaddr_in *)saddr)->sin_addr; 1371 mask = ((const struct sockaddr_in *)smask)->sin_addr; 1372 lle_addr.s_addr = ntohl(lle->r_l3addr.addr4.s_addr); 1373 1374 if (IN_ARE_MASKED_ADDR_EQUAL(lle_addr, addr, mask) == 0) 1375 return (0); 1376 1377 if (lle->la_flags & LLE_IFADDR) { 1378 /* 1379 * Delete LLE_IFADDR records IFF address & flag matches. 1380 * Note that addr is the interface address within prefix 1381 * being matched. 1382 * Note also we should handle 'ifdown' cases without removing 1383 * ifaddr macs. 1384 */ 1385 if (addr.s_addr == lle_addr.s_addr && (flags & LLE_STATIC) != 0) 1386 return (1); 1387 return (0); 1388 } 1389 1390 /* flags & LLE_STATIC means deleting both dynamic and static entries */ 1391 if ((flags & LLE_STATIC) || !(lle->la_flags & LLE_STATIC)) 1392 return (1); 1393 1394 return (0); 1395 } 1396 1397 static void 1398 in_lltable_free_entry(struct lltable *llt, struct llentry *lle) 1399 { 1400 size_t pkts_dropped; 1401 1402 LLE_WLOCK_ASSERT(lle); 1403 KASSERT(llt != NULL, ("lltable is NULL")); 1404 1405 /* Unlink entry from table if not already */ 1406 if ((lle->la_flags & LLE_LINKED) != 0) { 1407 IF_AFDATA_WLOCK_ASSERT(llt->llt_ifp); 1408 lltable_unlink_entry(llt, lle); 1409 } 1410 1411 /* Drop hold queue */ 1412 pkts_dropped = llentry_free(lle); 1413 ARPSTAT_ADD(dropped, pkts_dropped); 1414 } 1415 1416 static int 1417 in_lltable_rtcheck(struct ifnet *ifp, u_int flags, const struct sockaddr *l3addr) 1418 { 1419 struct nhop_object *nh; 1420 struct in_addr addr; 1421 1422 KASSERT(l3addr->sa_family == AF_INET, 1423 ("sin_family %d", l3addr->sa_family)); 1424 1425 addr = ((const struct sockaddr_in *)l3addr)->sin_addr; 1426 1427 nh = fib4_lookup(ifp->if_fib, addr, 0, NHR_NONE, 0); 1428 if (nh == NULL) 1429 return (EINVAL); 1430 1431 /* 1432 * If the gateway for an existing host route matches the target L3 1433 * address, which is a special route inserted by some implementation 1434 * such as MANET, and the interface is of the correct type, then 1435 * allow for ARP to proceed. 1436 */ 1437 if (nh->nh_flags & NHF_GATEWAY) { 1438 if (!(nh->nh_flags & NHF_HOST) || nh->nh_ifp->if_type != IFT_ETHER || 1439 (nh->nh_ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) != 0 || 1440 memcmp(nh->gw_sa.sa_data, l3addr->sa_data, 1441 sizeof(in_addr_t)) != 0) { 1442 return (EINVAL); 1443 } 1444 } 1445 1446 /* 1447 * Make sure that at least the destination address is covered 1448 * by the route. This is for handling the case where 2 or more 1449 * interfaces have the same prefix. An incoming packet arrives 1450 * on one interface and the corresponding outgoing packet leaves 1451 * another interface. 1452 */ 1453 if ((nh->nh_ifp != ifp) && (nh->nh_flags & NHF_HOST) == 0) { 1454 struct in_ifaddr *ia = (struct in_ifaddr *)ifaof_ifpforaddr(l3addr, ifp); 1455 struct in_addr dst_addr, mask_addr; 1456 1457 if (ia == NULL) 1458 return (EINVAL); 1459 1460 /* 1461 * ifaof_ifpforaddr() returns _best matching_ IFA. 1462 * It is possible that ifa prefix does not cover our address. 1463 * Explicitly verify and fail if that's the case. 1464 */ 1465 dst_addr = IA_SIN(ia)->sin_addr; 1466 mask_addr.s_addr = htonl(ia->ia_subnetmask); 1467 1468 if (!IN_ARE_MASKED_ADDR_EQUAL(dst_addr, addr, mask_addr)) 1469 return (EINVAL); 1470 } 1471 1472 return (0); 1473 } 1474 1475 static inline uint32_t 1476 in_lltable_hash_dst(const struct in_addr dst, uint32_t hsize) 1477 { 1478 1479 return (IN_LLTBL_HASH(dst.s_addr, hsize)); 1480 } 1481 1482 static uint32_t 1483 in_lltable_hash(const struct llentry *lle, uint32_t hsize) 1484 { 1485 1486 return (in_lltable_hash_dst(lle->r_l3addr.addr4, hsize)); 1487 } 1488 1489 static void 1490 in_lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa) 1491 { 1492 struct sockaddr_in *sin; 1493 1494 sin = (struct sockaddr_in *)sa; 1495 bzero(sin, sizeof(*sin)); 1496 sin->sin_family = AF_INET; 1497 sin->sin_len = sizeof(*sin); 1498 sin->sin_addr = lle->r_l3addr.addr4; 1499 } 1500 1501 static inline struct llentry * 1502 in_lltable_find_dst(struct lltable *llt, struct in_addr dst) 1503 { 1504 struct llentry *lle; 1505 struct llentries *lleh; 1506 u_int hashidx; 1507 1508 hashidx = in_lltable_hash_dst(dst, llt->llt_hsize); 1509 lleh = &llt->lle_head[hashidx]; 1510 CK_LIST_FOREACH(lle, lleh, lle_next) { 1511 if (lle->la_flags & LLE_DELETED) 1512 continue; 1513 if (lle->r_l3addr.addr4.s_addr == dst.s_addr) 1514 break; 1515 } 1516 1517 return (lle); 1518 } 1519 1520 static void 1521 in_lltable_delete_entry(struct lltable *llt, struct llentry *lle) 1522 { 1523 1524 lle->la_flags |= LLE_DELETED; 1525 EVENTHANDLER_INVOKE(lle_event, lle, LLENTRY_DELETED); 1526 #ifdef DIAGNOSTIC 1527 log(LOG_INFO, "ifaddr cache = %p is deleted\n", lle); 1528 #endif 1529 llentry_free(lle); 1530 } 1531 1532 static struct llentry * 1533 in_lltable_alloc(struct lltable *llt, u_int flags, const struct sockaddr *l3addr) 1534 { 1535 const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr; 1536 struct ifnet *ifp = llt->llt_ifp; 1537 struct llentry *lle; 1538 char linkhdr[LLE_MAX_LINKHDR]; 1539 size_t linkhdrsize; 1540 int lladdr_off; 1541 1542 KASSERT(l3addr->sa_family == AF_INET, 1543 ("sin_family %d", l3addr->sa_family)); 1544 1545 /* 1546 * A route that covers the given address must have 1547 * been installed 1st because we are doing a resolution, 1548 * verify this. 1549 */ 1550 if (!(flags & LLE_IFADDR) && 1551 in_lltable_rtcheck(ifp, flags, l3addr) != 0) 1552 return (NULL); 1553 1554 lle = in_lltable_new(sin->sin_addr, flags); 1555 if (lle == NULL) { 1556 log(LOG_INFO, "lla_lookup: new lle malloc failed\n"); 1557 return (NULL); 1558 } 1559 lle->la_flags = flags; 1560 if (flags & LLE_STATIC) 1561 lle->r_flags |= RLLE_VALID; 1562 if ((flags & LLE_IFADDR) == LLE_IFADDR) { 1563 linkhdrsize = LLE_MAX_LINKHDR; 1564 if (lltable_calc_llheader(ifp, AF_INET, IF_LLADDR(ifp), 1565 linkhdr, &linkhdrsize, &lladdr_off) != 0) { 1566 NET_EPOCH_CALL(in_lltable_destroy_lle_unlocked, &lle->lle_epoch_ctx); 1567 return (NULL); 1568 } 1569 lltable_set_entry_addr(ifp, lle, linkhdr, linkhdrsize, 1570 lladdr_off); 1571 lle->la_flags |= LLE_STATIC; 1572 lle->r_flags |= (RLLE_VALID | RLLE_IFADDR); 1573 } 1574 1575 return (lle); 1576 } 1577 1578 /* 1579 * Return NULL if not found or marked for deletion. 1580 * If found return lle read locked. 1581 */ 1582 static struct llentry * 1583 in_lltable_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr) 1584 { 1585 const struct sockaddr_in *sin = (const struct sockaddr_in *)l3addr; 1586 struct llentry *lle; 1587 1588 IF_AFDATA_LOCK_ASSERT(llt->llt_ifp); 1589 KASSERT(l3addr->sa_family == AF_INET, 1590 ("sin_family %d", l3addr->sa_family)); 1591 KASSERT((flags & (LLE_UNLOCKED | LLE_EXCLUSIVE)) != 1592 (LLE_UNLOCKED | LLE_EXCLUSIVE), 1593 ("wrong lle request flags: %#x", flags)); 1594 1595 lle = in_lltable_find_dst(llt, sin->sin_addr); 1596 if (lle == NULL) 1597 return (NULL); 1598 if (flags & LLE_UNLOCKED) 1599 return (lle); 1600 1601 if (flags & LLE_EXCLUSIVE) 1602 LLE_WLOCK(lle); 1603 else 1604 LLE_RLOCK(lle); 1605 1606 /* 1607 * If the afdata lock is not held, the LLE may have been unlinked while 1608 * we were blocked on the LLE lock. Check for this case. 1609 */ 1610 if (__predict_false((lle->la_flags & LLE_LINKED) == 0)) { 1611 if (flags & LLE_EXCLUSIVE) 1612 LLE_WUNLOCK(lle); 1613 else 1614 LLE_RUNLOCK(lle); 1615 return (NULL); 1616 } 1617 return (lle); 1618 } 1619 1620 static int 1621 in_lltable_dump_entry(struct lltable *llt, struct llentry *lle, 1622 struct sysctl_req *wr) 1623 { 1624 struct ifnet *ifp = llt->llt_ifp; 1625 /* XXX stack use */ 1626 struct { 1627 struct rt_msghdr rtm; 1628 struct sockaddr_in sin; 1629 struct sockaddr_dl sdl; 1630 } arpc; 1631 struct sockaddr_dl *sdl; 1632 int error; 1633 1634 bzero(&arpc, sizeof(arpc)); 1635 /* skip deleted entries */ 1636 if ((lle->la_flags & LLE_DELETED) == LLE_DELETED) 1637 return (0); 1638 /* Skip if jailed and not a valid IP of the prison. */ 1639 lltable_fill_sa_entry(lle,(struct sockaddr *)&arpc.sin); 1640 if (prison_if(wr->td->td_ucred, (struct sockaddr *)&arpc.sin) != 0) 1641 return (0); 1642 /* 1643 * produce a msg made of: 1644 * struct rt_msghdr; 1645 * struct sockaddr_in; (IPv4) 1646 * struct sockaddr_dl; 1647 */ 1648 arpc.rtm.rtm_msglen = sizeof(arpc); 1649 arpc.rtm.rtm_version = RTM_VERSION; 1650 arpc.rtm.rtm_type = RTM_GET; 1651 arpc.rtm.rtm_flags = RTF_UP; 1652 arpc.rtm.rtm_addrs = RTA_DST | RTA_GATEWAY; 1653 1654 /* publish */ 1655 if (lle->la_flags & LLE_PUB) 1656 arpc.rtm.rtm_flags |= RTF_ANNOUNCE; 1657 1658 sdl = &arpc.sdl; 1659 sdl->sdl_family = AF_LINK; 1660 sdl->sdl_len = sizeof(*sdl); 1661 sdl->sdl_index = ifp->if_index; 1662 sdl->sdl_type = ifp->if_type; 1663 if ((lle->la_flags & LLE_VALID) == LLE_VALID) { 1664 sdl->sdl_alen = ifp->if_addrlen; 1665 bcopy(lle->ll_addr, LLADDR(sdl), ifp->if_addrlen); 1666 } else { 1667 sdl->sdl_alen = 0; 1668 bzero(LLADDR(sdl), ifp->if_addrlen); 1669 } 1670 1671 arpc.rtm.rtm_rmx.rmx_expire = 1672 lle->la_flags & LLE_STATIC ? 0 : lle->la_expire; 1673 arpc.rtm.rtm_flags |= (RTF_HOST | RTF_LLDATA); 1674 if (lle->la_flags & LLE_STATIC) 1675 arpc.rtm.rtm_flags |= RTF_STATIC; 1676 if (lle->la_flags & LLE_IFADDR) 1677 arpc.rtm.rtm_flags |= RTF_PINNED; 1678 arpc.rtm.rtm_index = ifp->if_index; 1679 error = SYSCTL_OUT(wr, &arpc, sizeof(arpc)); 1680 1681 return (error); 1682 } 1683 1684 static struct lltable * 1685 in_lltattach(struct ifnet *ifp) 1686 { 1687 struct lltable *llt; 1688 1689 llt = lltable_allocate_htbl(IN_LLTBL_DEFAULT_HSIZE); 1690 llt->llt_af = AF_INET; 1691 llt->llt_ifp = ifp; 1692 1693 llt->llt_lookup = in_lltable_lookup; 1694 llt->llt_alloc_entry = in_lltable_alloc; 1695 llt->llt_delete_entry = in_lltable_delete_entry; 1696 llt->llt_dump_entry = in_lltable_dump_entry; 1697 llt->llt_hash = in_lltable_hash; 1698 llt->llt_fill_sa_entry = in_lltable_fill_sa_entry; 1699 llt->llt_free_entry = in_lltable_free_entry; 1700 llt->llt_match_prefix = in_lltable_match_prefix; 1701 llt->llt_mark_used = llentry_mark_used; 1702 lltable_link(llt); 1703 1704 return (llt); 1705 } 1706 1707 struct lltable * 1708 in_lltable_get(struct ifnet *ifp) 1709 { 1710 struct lltable *llt = NULL; 1711 1712 void *afdata_ptr = ifp->if_afdata[AF_INET]; 1713 if (afdata_ptr != NULL) 1714 llt = ((struct in_ifinfo *)afdata_ptr)->ii_llt; 1715 return (llt); 1716 } 1717 1718 void * 1719 in_domifattach(struct ifnet *ifp) 1720 { 1721 struct in_ifinfo *ii; 1722 1723 ii = malloc(sizeof(struct in_ifinfo), M_IFADDR, M_WAITOK|M_ZERO); 1724 1725 ii->ii_llt = in_lltattach(ifp); 1726 ii->ii_igmp = igmp_domifattach(ifp); 1727 1728 return (ii); 1729 } 1730 1731 void 1732 in_domifdetach(struct ifnet *ifp, void *aux) 1733 { 1734 struct in_ifinfo *ii = (struct in_ifinfo *)aux; 1735 1736 igmp_domifdetach(ifp); 1737 lltable_free(ii->ii_llt); 1738 free(ii, M_IFADDR); 1739 } 1740