scope6.c revision 245199
1/*- 2 * Copyright (C) 2000 WIDE Project. 3 * 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 * 3. Neither the name of the project 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 PROJECT 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 PROJECT 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 * $KAME: scope6.c,v 1.10 2000/07/24 13:29:31 itojun Exp $ 30 */ 31 32#include <sys/cdefs.h> 33__FBSDID("$FreeBSD: head/sys/netinet6/scope6.c 245199 2013-01-09 00:36:06Z ae $"); 34 35#include <sys/param.h> 36#include <sys/malloc.h> 37#include <sys/mbuf.h> 38#include <sys/socket.h> 39#include <sys/systm.h> 40#include <sys/queue.h> 41#include <sys/sysctl.h> 42#include <sys/syslog.h> 43 44#include <net/if.h> 45#include <net/vnet.h> 46 47#include <netinet/in.h> 48 49#include <netinet/ip6.h> 50#include <netinet6/in6_var.h> 51#include <netinet6/ip6_var.h> 52#include <netinet6/scope6_var.h> 53 54#ifdef ENABLE_DEFAULT_SCOPE 55VNET_DEFINE(int, ip6_use_defzone) = 1; 56#else 57VNET_DEFINE(int, ip6_use_defzone) = 0; 58#endif 59VNET_DEFINE(int, deembed_scopeid) = 1; 60SYSCTL_DECL(_net_inet6_ip6); 61SYSCTL_VNET_INT(_net_inet6_ip6, OID_AUTO, deembed_scopeid, CTLFLAG_RW, 62 &VNET_NAME(deembed_scopeid), 0, 63 "Extract embedded zone ID and set it to sin6_scope_id in sockaddr_in6."); 64 65/* 66 * The scope6_lock protects the global sid default stored in 67 * sid_default below. 68 */ 69static 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 75static VNET_DEFINE(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 81void 82scope6_init(void) 83{ 84 85 bzero(&V_sid_default, sizeof(V_sid_default)); 86 87 if (!IS_DEFAULT_VNET(curvnet)) 88 return; 89 90 SCOPE6_LOCK_INIT(); 91} 92 93struct scope6_id * 94scope6_ifattach(struct ifnet *ifp) 95{ 96 struct scope6_id *sid; 97 98 sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK); 99 bzero(sid, sizeof(*sid)); 100 101 /* 102 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 103 * Should we rather hardcode here? 104 */ 105 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 106 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 107#ifdef MULTI_SCOPE 108 /* by default, we don't care about scope boundary for these scopes. */ 109 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1; 110 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1; 111#endif 112 113 return sid; 114} 115 116void 117scope6_ifdetach(struct scope6_id *sid) 118{ 119 120 free(sid, M_IFADDR); 121} 122 123int 124scope6_set(struct ifnet *ifp, struct scope6_id *idlist) 125{ 126 int i; 127 int error = 0; 128 struct scope6_id *sid = NULL; 129 130 IF_AFDATA_WLOCK(ifp); 131 sid = SID(ifp); 132 133 if (!sid) { /* paranoid? */ 134 IF_AFDATA_WUNLOCK(ifp); 135 return (EINVAL); 136 } 137 138 /* 139 * XXX: We need more consistency checks of the relationship among 140 * scopes (e.g. an organization should be larger than a site). 141 */ 142 143 /* 144 * TODO(XXX): after setting, we should reflect the changes to 145 * interface addresses, routing table entries, PCB entries... 146 */ 147 148 for (i = 0; i < 16; i++) { 149 if (idlist->s6id_list[i] && 150 idlist->s6id_list[i] != sid->s6id_list[i]) { 151 /* 152 * An interface zone ID must be the corresponding 153 * interface index by definition. 154 */ 155 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 156 idlist->s6id_list[i] != ifp->if_index) { 157 IF_AFDATA_WUNLOCK(ifp); 158 return (EINVAL); 159 } 160 161 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 162 idlist->s6id_list[i] > V_if_index) { 163 /* 164 * XXX: theoretically, there should be no 165 * relationship between link IDs and interface 166 * IDs, but we check the consistency for 167 * safety in later use. 168 */ 169 IF_AFDATA_WUNLOCK(ifp); 170 return (EINVAL); 171 } 172 173 /* 174 * XXX: we must need lots of work in this case, 175 * but we simply set the new value in this initial 176 * implementation. 177 */ 178 sid->s6id_list[i] = idlist->s6id_list[i]; 179 } 180 } 181 IF_AFDATA_WUNLOCK(ifp); 182 183 return (error); 184} 185 186int 187scope6_get(struct ifnet *ifp, struct scope6_id *idlist) 188{ 189 struct scope6_id *sid; 190 191 /* We only need to lock the interface's afdata for SID() to work. */ 192 IF_AFDATA_RLOCK(ifp); 193 sid = SID(ifp); 194 if (sid == NULL) { /* paranoid? */ 195 IF_AFDATA_RUNLOCK(ifp); 196 return (EINVAL); 197 } 198 199 *idlist = *sid; 200 201 IF_AFDATA_RUNLOCK(ifp); 202 return (0); 203} 204 205 206/* 207 * Get a scope of the address. Node-local, link-local, site-local or global. 208 */ 209int 210in6_addrscope(struct in6_addr *addr) 211{ 212 int scope; 213 214 if (addr->s6_addr[0] == 0xfe) { 215 scope = addr->s6_addr[1] & 0xc0; 216 217 switch (scope) { 218 case 0x80: 219 return IPV6_ADDR_SCOPE_LINKLOCAL; 220 break; 221 case 0xc0: 222 return IPV6_ADDR_SCOPE_SITELOCAL; 223 break; 224 default: 225 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */ 226 break; 227 } 228 } 229 230 231 if (addr->s6_addr[0] == 0xff) { 232 scope = addr->s6_addr[1] & 0x0f; 233 234 /* 235 * due to other scope such as reserved, 236 * return scope doesn't work. 237 */ 238 switch (scope) { 239 case IPV6_ADDR_SCOPE_INTFACELOCAL: 240 return IPV6_ADDR_SCOPE_INTFACELOCAL; 241 break; 242 case IPV6_ADDR_SCOPE_LINKLOCAL: 243 return IPV6_ADDR_SCOPE_LINKLOCAL; 244 break; 245 case IPV6_ADDR_SCOPE_SITELOCAL: 246 return IPV6_ADDR_SCOPE_SITELOCAL; 247 break; 248 default: 249 return IPV6_ADDR_SCOPE_GLOBAL; 250 break; 251 } 252 } 253 254 /* 255 * Regard loopback and unspecified addresses as global, since 256 * they have no ambiguity. 257 */ 258 if (bcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) { 259 if (addr->s6_addr[15] == 1) /* loopback */ 260 return IPV6_ADDR_SCOPE_LINKLOCAL; 261 if (addr->s6_addr[15] == 0) /* unspecified */ 262 return IPV6_ADDR_SCOPE_GLOBAL; /* XXX: correct? */ 263 } 264 265 return IPV6_ADDR_SCOPE_GLOBAL; 266} 267 268/* 269 * ifp - note that this might be NULL 270 */ 271 272void 273scope6_setdefault(struct ifnet *ifp) 274{ 275 276 /* 277 * Currently, this function just sets the default "interfaces" 278 * and "links" according to the given interface. 279 * We might eventually have to separate the notion of "link" from 280 * "interface" and provide a user interface to set the default. 281 */ 282 SCOPE6_LOCK(); 283 if (ifp) { 284 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 285 ifp->if_index; 286 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 287 ifp->if_index; 288 } else { 289 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 290 V_sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 291 } 292 SCOPE6_UNLOCK(); 293} 294 295int 296scope6_get_default(struct scope6_id *idlist) 297{ 298 299 SCOPE6_LOCK(); 300 *idlist = V_sid_default; 301 SCOPE6_UNLOCK(); 302 303 return (0); 304} 305 306u_int32_t 307scope6_addr2default(struct in6_addr *addr) 308{ 309 u_int32_t id; 310 311 /* 312 * special case: The loopback address should be considered as 313 * link-local, but there's no ambiguity in the syntax. 314 */ 315 if (IN6_IS_ADDR_LOOPBACK(addr)) 316 return (0); 317 318 /* 319 * XXX: 32-bit read is atomic on all our platforms, is it OK 320 * not to lock here? 321 */ 322 SCOPE6_LOCK(); 323 id = V_sid_default.s6id_list[in6_addrscope(addr)]; 324 SCOPE6_UNLOCK(); 325 return (id); 326} 327 328/* 329 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 330 * is unspecified (=0), needs to be specified, and the default zone ID can be 331 * used, the default value will be used. 332 * This routine then generates the kernel-internal form: if the address scope 333 * of is interface-local or link-local, embed the interface index in the 334 * address. 335 */ 336int 337sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 338{ 339 struct ifnet *ifp; 340 u_int32_t zoneid; 341 342 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 343 zoneid = scope6_addr2default(&sin6->sin6_addr); 344 345 if (zoneid != 0 && 346 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 347 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 348 /* 349 * At this moment, we only check interface-local and 350 * link-local scope IDs, and use interface indices as the 351 * zone IDs assuming a one-to-one mapping between interfaces 352 * and links. 353 */ 354 if (V_if_index < zoneid) 355 return (ENXIO); 356 ifp = ifnet_byindex(zoneid); 357 if (ifp == NULL) /* XXX: this can happen for some OS */ 358 return (ENXIO); 359 360 /* XXX assignment to 16bit from 32bit variable */ 361 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 362 363 sin6->sin6_scope_id = 0; 364 } 365 366 return 0; 367} 368 369/* 370 * generate standard sockaddr_in6 from embedded form. 371 */ 372int 373sa6_recoverscope(struct sockaddr_in6 *sin6) 374{ 375 char ip6buf[INET6_ADDRSTRLEN]; 376 u_int32_t zoneid; 377 378 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 379 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 380 /* 381 * KAME assumption: link id == interface id 382 */ 383 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 384 if (zoneid) { 385 /* sanity check */ 386 if (V_if_index < zoneid) 387 return (ENXIO); 388#if 0 389 /* XXX: Disabled due to possible deadlock. */ 390 if (!ifnet_byindex(zoneid)) 391 return (ENXIO); 392#endif 393 if (sin6->sin6_scope_id != 0 && 394 zoneid != sin6->sin6_scope_id) { 395 log(LOG_NOTICE, 396 "%s: embedded scope mismatch: %s%%%d. " 397 "sin6_scope_id was overridden.", __func__, 398 ip6_sprintf(ip6buf, &sin6->sin6_addr), 399 sin6->sin6_scope_id); 400 } 401 sin6->sin6_addr.s6_addr16[1] = 0; 402 sin6->sin6_scope_id = zoneid; 403 } 404 } 405 406 return 0; 407} 408 409/* 410 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 411 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 412 * in the in6_addr structure, in6 will be modified. 413 * 414 * ret_id - unnecessary? 415 */ 416int 417in6_setscope(struct in6_addr *in6, struct ifnet *ifp, u_int32_t *ret_id) 418{ 419 int scope; 420 u_int32_t zoneid = 0; 421 struct scope6_id *sid; 422 423 /* 424 * special case: the loopback address can only belong to a loopback 425 * interface. 426 */ 427 if (IN6_IS_ADDR_LOOPBACK(in6)) { 428 if (!(ifp->if_flags & IFF_LOOPBACK)) { 429 return (EINVAL); 430 } else { 431 if (ret_id != NULL) 432 *ret_id = 0; /* there's no ambiguity */ 433 return (0); 434 } 435 } 436 437 if (ret_id == NULL && !IN6_IS_SCOPE_EMBED(in6)) 438 return (0); 439 440 IF_AFDATA_RLOCK(ifp); 441 442 sid = SID(ifp); 443 444#ifdef DIAGNOSTIC 445 if (sid == NULL) { /* should not happen */ 446 panic("in6_setscope: scope array is NULL"); 447 /* NOTREACHED */ 448 } 449#endif 450 451 scope = in6_addrscope(in6); 452 switch (scope) { 453 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ 454 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; 455 break; 456 457 case IPV6_ADDR_SCOPE_LINKLOCAL: 458 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; 459 break; 460 461 case IPV6_ADDR_SCOPE_SITELOCAL: 462 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; 463 break; 464 465 case IPV6_ADDR_SCOPE_ORGLOCAL: 466 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; 467 break; 468 469 default: 470 zoneid = 0; /* XXX: treat as global. */ 471 break; 472 } 473 IF_AFDATA_RUNLOCK(ifp); 474 475 if (ret_id != NULL) 476 *ret_id = zoneid; 477 478 if (IN6_IS_SCOPE_EMBED(in6)) 479 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 480 481 return (0); 482} 483 484/* 485 * Just clear the embedded scope identifier. Return 0 if the original address 486 * is intact; return non 0 if the address is modified. 487 */ 488int 489in6_clearscope(struct in6_addr *in6) 490{ 491 int modified = 0; 492 493 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 494 if (in6->s6_addr16[1] != 0) 495 modified = 1; 496 in6->s6_addr16[1] = 0; 497 } 498 499 return (modified); 500} 501 502/* 503 * Return the scope identifier or zero. 504 */ 505uint16_t 506in6_getscope(struct in6_addr *in6) 507{ 508 509 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) 510 return (in6->s6_addr16[1]); 511 512 return (0); 513} 514