1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (C) 2000 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $ 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.h> 38 #include <sys/malloc.h> 39 #include <sys/mbuf.h> 40 #include <sys/socket.h> 41 #include <sys/sockio.h> 42 #include <sys/systm.h> 43 #include <sys/queue.h> 44 #include <sys/sysctl.h> 45 #include <sys/syslog.h> 46 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <net/vnet.h> 50 51 #include <netinet/in.h> 52 53 #include <netinet/ip6.h> 54 #include <netinet6/in6_var.h> 55 #include <netinet6/ip6_var.h> 56 #include <netinet6/scope6_var.h> 57 58 #ifdef ENABLE_DEFAULT_SCOPE 59 VNET_DEFINE(int, ip6_use_defzone) = 1; 60 #else 61 VNET_DEFINE(int, ip6_use_defzone) = 0; 62 #endif 63 SYSCTL_DECL(_net_inet6_ip6); 64 65 /* 66 * The scope6_lock protects the global sid default stored in 67 * sid_default below. 68 */ 69 static struct mtx scope6_lock; 70 #define SCOPE6_LOCK_INIT() mtx_init(&scope6_lock, "scope6_lock", NULL, MTX_DEF) 71 #define SCOPE6_LOCK() mtx_lock(&scope6_lock) 72 #define SCOPE6_UNLOCK() mtx_unlock(&scope6_lock) 73 #define SCOPE6_LOCK_ASSERT() mtx_assert(&scope6_lock, MA_OWNED) 74 75 VNET_DEFINE_STATIC(struct scope6_id, sid_default); 76 #define V_sid_default VNET(sid_default) 77 78 #define SID(ifp) \ 79 (((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 80 81 static int scope6_get(struct ifnet *, struct scope6_id *); 82 static int scope6_set(struct ifnet *, struct scope6_id *); 83 84 void 85 scope6_init(void) 86 { 87 88 bzero(&V_sid_default, sizeof(V_sid_default)); 89 90 if (!IS_DEFAULT_VNET(curvnet)) 91 return; 92 93 SCOPE6_LOCK_INIT(); 94 } 95 96 struct scope6_id * 97 scope6_ifattach(struct ifnet *ifp) 98 { 99 struct scope6_id *sid; 100 101 sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO); 102 /* 103 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 104 * Should we rather hardcode here? 105 */ 106 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 107 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 108 return (sid); 109 } 110 111 void 112 scope6_ifdetach(struct scope6_id *sid) 113 { 114 115 free(sid, M_IFADDR); 116 } 117 118 int 119 scope6_ioctl(u_long cmd, caddr_t data, struct ifnet *ifp) 120 { 121 struct in6_ifreq *ifr; 122 123 if (ifp->if_afdata[AF_INET6] == NULL) 124 return (EPFNOSUPPORT); 125 126 ifr = (struct in6_ifreq *)data; 127 switch (cmd) { 128 case SIOCSSCOPE6: 129 return (scope6_set(ifp, 130 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 131 case SIOCGSCOPE6: 132 return (scope6_get(ifp, 133 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 134 case SIOCGSCOPE6DEF: 135 return (scope6_get_default( 136 (struct scope6_id *)ifr->ifr_ifru.ifru_scope_id)); 137 default: 138 return (EOPNOTSUPP); 139 } 140 } 141 142 static int 143 scope6_set(struct ifnet *ifp, struct scope6_id *idlist) 144 { 145 int i; 146 int error = 0; 147 struct scope6_id *sid = NULL; 148 149 IF_AFDATA_WLOCK(ifp); 150 sid = SID(ifp); 151 152 if (!sid) { /* paranoid? */ 153 IF_AFDATA_WUNLOCK(ifp); 154 return (EINVAL); 155 } 156 157 /* 158 * XXX: We need more consistency checks of the relationship among 159 * scopes (e.g. an organization should be larger than a site). 160 */ 161 162 /* 163 * TODO(XXX): after setting, we should reflect the changes to 164 * interface addresses, routing table entries, PCB entries... 165 */ 166 167 for (i = 0; i < 16; i++) { 168 if (idlist->s6id_list[i] && 169 idlist->s6id_list[i] != sid->s6id_list[i]) { 170 /* 171 * An interface zone ID must be the corresponding 172 * interface index by definition. 173 */ 174 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 175 idlist->s6id_list[i] != ifp->if_index) { 176 IF_AFDATA_WUNLOCK(ifp); 177 return (EINVAL); 178 } 179 180 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 181 idlist->s6id_list[i] > V_if_index) { 182 /* 183 * XXX: theoretically, there should be no 184 * relationship between link IDs and interface 185 * IDs, but we check the consistency for 186 * safety in later use. 187 */ 188 IF_AFDATA_WUNLOCK(ifp); 189 return (EINVAL); 190 } 191 192 /* 193 * XXX: we must need lots of work in this case, 194 * but we simply set the new value in this initial 195 * implementation. 196 */ 197 sid->s6id_list[i] = idlist->s6id_list[i]; 198 } 199 } 200 IF_AFDATA_WUNLOCK(ifp); 201 202 return (error); 203 } 204 205 static int 206 scope6_get(struct ifnet *ifp, struct scope6_id *idlist) 207 { 208 struct epoch_tracker et; 209 struct scope6_id *sid; 210 211 /* We only need to lock the interface's afdata for SID() to work. */ 212 NET_EPOCH_ENTER(et); 213 sid = SID(ifp); 214 if (sid == NULL) { /* paranoid? */ 215 NET_EPOCH_EXIT(et); 216 return (EINVAL); 217 } 218 219 *idlist = *sid; 220 221 NET_EPOCH_EXIT(et); 222 return (0); 223 } 224 225 /* 226 * Get a scope of the address. Node-local, link-local, site-local or global. 227 */ 228 int 229 in6_addrscope(const struct in6_addr *addr) 230 { 231 232 if (IN6_IS_ADDR_MULTICAST(addr)) { 233 /* 234 * Addresses with reserved value F must be treated as 235 * global multicast addresses. 236 */ 237 if (IPV6_ADDR_MC_SCOPE(addr) == 0x0f) 238 return (IPV6_ADDR_SCOPE_GLOBAL); 239 return (IPV6_ADDR_MC_SCOPE(addr)); 240 } 241 if (IN6_IS_ADDR_LINKLOCAL(addr) || 242 IN6_IS_ADDR_LOOPBACK(addr)) 243 return (IPV6_ADDR_SCOPE_LINKLOCAL); 244 if (IN6_IS_ADDR_SITELOCAL(addr)) 245 return (IPV6_ADDR_SCOPE_SITELOCAL); 246 return (IPV6_ADDR_SCOPE_GLOBAL); 247 } 248 249 /* 250 * ifp - note that this might be NULL 251 */ 252 253 void 254 scope6_setdefault(struct ifnet *ifp) 255 { 256 257 /* 258 * Currently, this function just sets the default "interfaces" 259 * and "links" according to the given interface. 260 * We might eventually have to separate the notion of "link" from 261 * "interface" and provide a user interface to set the default. 262 */ 263 SCOPE6_LOCK(); 264 if (ifp) { 265 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 266 ifp->if_index; 267 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 268 ifp->if_index; 269 } else { 270 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 271 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 272 } 273 SCOPE6_UNLOCK(); 274 } 275 276 int 277 scope6_get_default(struct scope6_id *idlist) 278 { 279 280 SCOPE6_LOCK(); 281 *idlist = V_sid_default; 282 SCOPE6_UNLOCK(); 283 284 return (0); 285 } 286 287 u_int32_t 288 scope6_addr2default(struct in6_addr *addr) 289 { 290 u_int32_t id; 291 292 /* 293 * special case: The loopback address should be considered as 294 * link-local, but there's no ambiguity in the syntax. 295 */ 296 if (IN6_IS_ADDR_LOOPBACK(addr)) 297 return (0); 298 299 /* 300 * XXX: 32-bit read is atomic on all our platforms, is it OK 301 * not to lock here? 302 */ 303 SCOPE6_LOCK(); 304 id = V_sid_default.s6id_list[in6_addrscope(addr)]; 305 SCOPE6_UNLOCK(); 306 return (id); 307 } 308 309 /* 310 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 311 * is unspecified (=0), needs to be specified, and the default zone ID can be 312 * used, the default value will be used. 313 * This routine then generates the kernel-internal form: if the address scope 314 * of is interface-local or link-local, embed the interface index in the 315 * address. 316 */ 317 int 318 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 319 { 320 u_int32_t zoneid; 321 322 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 323 zoneid = scope6_addr2default(&sin6->sin6_addr); 324 325 if (zoneid != 0 && 326 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 327 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 328 /* 329 * At this moment, we only check interface-local and 330 * link-local scope IDs, and use interface indices as the 331 * zone IDs assuming a one-to-one mapping between interfaces 332 * and links. 333 */ 334 if (V_if_index < zoneid || ifnet_byindex(zoneid) == NULL) 335 return (ENXIO); 336 337 /* XXX assignment to 16bit from 32bit variable */ 338 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 339 sin6->sin6_scope_id = 0; 340 } 341 342 return 0; 343 } 344 345 /* 346 * generate standard sockaddr_in6 from embedded form. 347 */ 348 int 349 sa6_recoverscope(struct sockaddr_in6 *sin6) 350 { 351 char ip6buf[INET6_ADDRSTRLEN]; 352 u_int32_t zoneid; 353 354 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 355 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 356 /* 357 * KAME assumption: link id == interface id 358 */ 359 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 360 if (zoneid) { 361 /* sanity check */ 362 if (V_if_index < zoneid) 363 return (ENXIO); 364 #if 0 365 /* XXX: Disabled due to possible deadlock. */ 366 if (!ifnet_byindex(zoneid)) 367 return (ENXIO); 368 #endif 369 if (sin6->sin6_scope_id != 0 && 370 zoneid != sin6->sin6_scope_id) { 371 log(LOG_NOTICE, 372 "%s: embedded scope mismatch: %s%%%d. " 373 "sin6_scope_id was overridden\n", __func__, 374 ip6_sprintf(ip6buf, &sin6->sin6_addr), 375 sin6->sin6_scope_id); 376 } 377 sin6->sin6_addr.s6_addr16[1] = 0; 378 sin6->sin6_scope_id = zoneid; 379 } 380 } 381 382 return 0; 383 } 384 385 /* 386 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 387 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 388 * in the in6_addr structure, in6 will be modified. 389 * 390 * ret_id - unnecessary? 391 */ 392 int 393 in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) 394 { 395 int scope; 396 u_int32_t zoneid = 0; 397 struct scope6_id *sid; 398 399 /* 400 * special case: the loopback address can only belong to a loopback 401 * interface. 402 */ 403 if (IN6_IS_ADDR_LOOPBACK(in6)) { 404 if (!(ifp->if_flags & IFF_LOOPBACK)) 405 return (EINVAL); 406 } else { 407 scope = in6_addrscope(in6); 408 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 409 scope == IPV6_ADDR_SCOPE_LINKLOCAL) { 410 /* 411 * Currently we use interface indices as the 412 * zone IDs for interface-local and link-local 413 * scopes. 414 */ 415 zoneid = ifp->if_index; 416 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 417 } else if (scope != IPV6_ADDR_SCOPE_GLOBAL) { 418 struct epoch_tracker et; 419 420 NET_EPOCH_ENTER(et); 421 if (ifp->if_afdata[AF_INET6] == NULL) { 422 NET_EPOCH_EXIT(et); 423 return (ENETDOWN); 424 } 425 sid = SID(ifp); 426 zoneid = sid->s6id_list[scope]; 427 NET_EPOCH_EXIT(et); 428 } 429 } 430 431 if (ret_id != NULL) 432 *ret_id = zoneid; 433 434 return (0); 435 } 436 437 /* 438 * Just clear the embedded scope identifier. Return 0 if the original address 439 * is intact; return non 0 if the address is modified. 440 */ 441 int 442 in6_clearscope(struct in6_addr *in6) 443 { 444 int modified = 0; 445 446 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 447 if (in6->s6_addr16[1] != 0) 448 modified = 1; 449 in6->s6_addr16[1] = 0; 450 } 451 452 return (modified); 453 } 454 455 /* 456 * Return the scope identifier or zero. 457 */ 458 uint16_t 459 in6_getscope(const struct in6_addr *in6) 460 { 461 462 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) 463 return (in6->s6_addr16[1]); 464 465 return (0); 466 } 467 468 /* 469 * Returns scope zone id for the unicast address @in6. 470 * 471 * Returns 0 for global unicast and loopback addresses. 472 * Returns interface index for the link-local addresses. 473 */ 474 uint32_t 475 in6_get_unicast_scopeid(const struct in6_addr *in6, const struct ifnet *ifp) 476 { 477 478 if (IN6_IS_SCOPE_LINKLOCAL(in6)) 479 return (ifp->if_index); 480 return (0); 481 } 482 483 void 484 in6_set_unicast_scopeid(struct in6_addr *in6, uint32_t scopeid) 485 { 486 487 in6->s6_addr16[1] = htons(scopeid & 0xffff); 488 } 489 490 /* 491 * Return pointer to ifnet structure, corresponding to the zone id of 492 * link-local scope. 493 */ 494 struct ifnet* 495 in6_getlinkifnet(uint32_t zoneid) 496 { 497 498 return (ifnet_byindex((u_short)zoneid)); 499 } 500 501 /* 502 * Return zone id for the specified scope. 503 */ 504 uint32_t 505 in6_getscopezone(const struct ifnet *ifp, int scope) 506 { 507 508 if (scope == IPV6_ADDR_SCOPE_INTFACELOCAL || 509 scope == IPV6_ADDR_SCOPE_LINKLOCAL) 510 return (ifp->if_index); 511 if (scope >= 0 && scope < IPV6_ADDR_SCOPES_COUNT) 512 return (SID(ifp)->s6id_list[scope]); 513 return (0); 514 } 515 516 /* 517 * Extracts scope from adddress @dst, stores cleared address 518 * inside @dst and zone inside @scopeid 519 */ 520 void 521 in6_splitscope(const struct in6_addr *src, struct in6_addr *dst, 522 uint32_t *scopeid) 523 { 524 uint32_t zoneid; 525 526 *dst = *src; 527 zoneid = ntohs(in6_getscope(dst)); 528 in6_clearscope(dst); 529 *scopeid = zoneid; 530 } 531 532 /* 533 * This function is for checking sockaddr_in6 structure passed 534 * from the application level (usually). 535 * 536 * sin6_scope_id should be set for link-local unicast, link-local and 537 * interface-local multicast addresses. 538 * 539 * If it is zero, then look into default zone ids. If default zone id is 540 * not set or disabled, then return error. 541 */ 542 int 543 sa6_checkzone(struct sockaddr_in6 *sa6) 544 { 545 int scope; 546 547 scope = in6_addrscope(&sa6->sin6_addr); 548 if (scope == IPV6_ADDR_SCOPE_GLOBAL) 549 return (sa6->sin6_scope_id ? EINVAL: 0); 550 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr) && 551 scope != IPV6_ADDR_SCOPE_LINKLOCAL && 552 scope != IPV6_ADDR_SCOPE_INTFACELOCAL) { 553 if (sa6->sin6_scope_id == 0 && V_ip6_use_defzone != 0) 554 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 555 return (0); 556 } 557 /* 558 * Since ::1 address always configured on the lo0, we can 559 * automatically set its zone id, when it is not specified. 560 * Return error, when specified zone id doesn't match with 561 * actual value. 562 */ 563 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) { 564 if (sa6->sin6_scope_id == 0) 565 sa6->sin6_scope_id = in6_getscopezone(V_loif, scope); 566 else if (sa6->sin6_scope_id != in6_getscopezone(V_loif, scope)) 567 return (EADDRNOTAVAIL); 568 } 569 /* XXX: we can validate sin6_scope_id here */ 570 if (sa6->sin6_scope_id != 0) 571 return (0); 572 if (V_ip6_use_defzone != 0) 573 sa6->sin6_scope_id = V_sid_default.s6id_list[scope]; 574 /* Return error if we can't determine zone id */ 575 return (sa6->sin6_scope_id ? 0: EADDRNOTAVAIL); 576 } 577 578 /* 579 * This function is similar to sa6_checkzone, but it uses given ifp 580 * to initialize sin6_scope_id. 581 */ 582 int 583 sa6_checkzone_ifp(struct ifnet *ifp, struct sockaddr_in6 *sa6) 584 { 585 int scope; 586 587 scope = in6_addrscope(&sa6->sin6_addr); 588 if (scope == IPV6_ADDR_SCOPE_LINKLOCAL || 589 scope == IPV6_ADDR_SCOPE_INTFACELOCAL) { 590 if (sa6->sin6_scope_id == 0) { 591 sa6->sin6_scope_id = in6_getscopezone(ifp, scope); 592 return (0); 593 } else if (sa6->sin6_scope_id != in6_getscopezone(ifp, scope)) 594 return (EADDRNOTAVAIL); 595 } 596 return (sa6_checkzone(sa6)); 597 } 598