1 /* $NetBSD: scope6.c,v 1.19 2018/02/01 16:36:01 maxv Exp $ */ 2 /* $KAME$ */ 3 4 /* 5 * Copyright (C) 2000 WIDE Project. 6 * 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 project 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 PROJECT 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 PROJECT 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 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: scope6.c,v 1.19 2018/02/01 16:36:01 maxv Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/malloc.h> 38 #include <sys/mbuf.h> 39 #include <sys/socket.h> 40 #include <sys/systm.h> 41 #include <sys/queue.h> 42 #include <sys/syslog.h> 43 44 #include <net/if.h> 45 #include <net/net_osdep.h> 46 47 #include <netinet/in.h> 48 49 #include <netinet6/in6_var.h> 50 #include <netinet6/scope6_var.h> 51 52 #ifdef ENABLE_DEFAULT_SCOPE 53 int ip6_use_defzone = 1; 54 #else 55 int ip6_use_defzone = 0; 56 #endif 57 58 static struct scope6_id sid_default; 59 #define SID(ifp) \ 60 ((ifp)->if_afdata[AF_INET6] == NULL ? NULL : \ 61 ((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 62 63 void 64 scope6_init(void) 65 { 66 67 memset(&sid_default, 0, sizeof(sid_default)); 68 } 69 70 struct scope6_id * 71 scope6_ifattach(struct ifnet *ifp) 72 { 73 struct scope6_id *sid; 74 75 sid = malloc(sizeof(*sid), M_IFADDR, M_WAITOK | M_ZERO); 76 77 /* 78 * XXX: IPV6_ADDR_SCOPE_xxx macros are not standard. 79 * Should we rather hardcode here? 80 */ 81 sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = ifp->if_index; 82 sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = ifp->if_index; 83 #ifdef MULTI_SCOPE 84 /* by default, we don't care about scope boundary for these scopes. */ 85 sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL] = 1; 86 sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL] = 1; 87 #endif 88 89 return sid; 90 } 91 92 void 93 scope6_ifdetach(struct scope6_id *sid) 94 { 95 96 free(sid, M_IFADDR); 97 } 98 99 int 100 scope6_set(struct ifnet *ifp, const struct scope6_id *idlist) 101 { 102 int i; 103 int error = 0; 104 struct scope6_id *sid = SID(ifp); 105 106 if (!sid) /* paranoid? */ 107 return EINVAL; 108 109 /* 110 * XXX: We need more consistency checks of the relationship among 111 * scopes (e.g. an organization should be larger than a site). 112 */ 113 114 /* 115 * TODO(XXX): after setting, we should reflect the changes to 116 * interface addresses, routing table entries, PCB entries... 117 */ 118 119 for (i = 0; i < 16; i++) { 120 if (idlist->s6id_list[i] && 121 idlist->s6id_list[i] != sid->s6id_list[i]) { 122 int s; 123 /* 124 * An interface zone ID must be the corresponding 125 * interface index by definition. 126 */ 127 if (i == IPV6_ADDR_SCOPE_INTFACELOCAL && 128 idlist->s6id_list[i] != ifp->if_index) 129 return EINVAL; 130 131 s = pserialize_read_enter(); 132 if (i == IPV6_ADDR_SCOPE_LINKLOCAL && 133 !if_byindex(idlist->s6id_list[i])) { 134 /* 135 * XXX: theoretically, there should be no 136 * relationship between link IDs and interface 137 * IDs, but we check the consistency for 138 * safety in later use. 139 */ 140 pserialize_read_exit(s); 141 return EINVAL; 142 } 143 pserialize_read_exit(s); 144 145 /* 146 * XXX: we must need lots of work in this case, 147 * but we simply set the new value in this initial 148 * implementation. 149 */ 150 sid->s6id_list[i] = idlist->s6id_list[i]; 151 } 152 } 153 154 return error; 155 } 156 157 int 158 scope6_get(const struct ifnet *ifp, struct scope6_id *idlist) 159 { 160 /* We only need to lock the interface's afdata for SID() to work. */ 161 const struct scope6_id *sid = SID(ifp); 162 163 if (sid == NULL) /* paranoid? */ 164 return EINVAL; 165 166 *idlist = *sid; 167 168 return 0; 169 } 170 171 /* 172 * Get a scope of the address. Interface-local, link-local, site-local 173 * or global. 174 */ 175 int 176 in6_addrscope(const struct in6_addr *addr) 177 { 178 int scope; 179 180 if (addr->s6_addr[0] == 0xfe) { 181 scope = addr->s6_addr[1] & 0xc0; 182 183 switch (scope) { 184 case 0x80: 185 return IPV6_ADDR_SCOPE_LINKLOCAL; 186 case 0xc0: 187 return IPV6_ADDR_SCOPE_SITELOCAL; 188 default: 189 return IPV6_ADDR_SCOPE_GLOBAL; /* just in case */ 190 } 191 } 192 193 if (addr->s6_addr[0] == 0xff) { 194 scope = addr->s6_addr[1] & 0x0f; 195 196 /* 197 * due to other scope such as reserved, 198 * return scope doesn't work. 199 */ 200 switch (scope) { 201 case IPV6_ADDR_SCOPE_INTFACELOCAL: 202 return IPV6_ADDR_SCOPE_INTFACELOCAL; 203 case IPV6_ADDR_SCOPE_LINKLOCAL: 204 return IPV6_ADDR_SCOPE_LINKLOCAL; 205 case IPV6_ADDR_SCOPE_SITELOCAL: 206 return IPV6_ADDR_SCOPE_SITELOCAL; 207 default: 208 return IPV6_ADDR_SCOPE_GLOBAL; 209 } 210 } 211 212 if (memcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) { 213 if (addr->s6_addr[15] == 1) /* loopback */ 214 return IPV6_ADDR_SCOPE_LINKLOCAL; 215 if (addr->s6_addr[15] == 0) { 216 /* 217 * Regard the unspecified addresses as global, 218 * since it has no ambiguity. 219 * XXX: not sure if it's correct... 220 */ 221 return IPV6_ADDR_SCOPE_GLOBAL; 222 } 223 } 224 225 return IPV6_ADDR_SCOPE_GLOBAL; 226 } 227 228 /* note that ifp argument might be NULL */ 229 void 230 scope6_setdefault(struct ifnet *ifp) 231 { 232 233 /* 234 * Currently, this function just sets the default "interfaces" 235 * and "links" according to the given interface. 236 * We might eventually have to separate the notion of "link" from 237 * "interface" and provide a user interface to set the default. 238 */ 239 if (ifp) { 240 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 241 ifp->if_index; 242 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 243 ifp->if_index; 244 } else { 245 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 246 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 247 } 248 } 249 250 int 251 scope6_get_default(struct scope6_id *idlist) 252 { 253 254 *idlist = sid_default; 255 256 return 0; 257 } 258 259 uint32_t 260 scope6_addr2default(const struct in6_addr *addr) 261 { 262 uint32_t id; 263 264 /* 265 * special case: The loopback address should be considered as 266 * link-local, but there's no ambiguity in the syntax. 267 */ 268 if (IN6_IS_ADDR_LOOPBACK(addr)) 269 return 0; 270 271 /* 272 * XXX: 32-bit read is atomic on all our platforms, is it OK 273 * not to lock here? 274 */ 275 id = sid_default.s6id_list[in6_addrscope(addr)]; 276 277 return id; 278 } 279 280 /* 281 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 282 * is unspecified (=0), needs to be specified, and the default zone ID can be 283 * used, the default value will be used. 284 * This routine then generates the kernel-internal form: if the address scope 285 * of is interface-local or link-local, embed the interface index in the 286 * address. 287 */ 288 int 289 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 290 { 291 struct ifnet *ifp; 292 uint32_t zoneid; 293 294 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 295 zoneid = scope6_addr2default(&sin6->sin6_addr); 296 297 if (zoneid != 0 && 298 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 299 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 300 int s; 301 /* 302 * At this moment, we only check interface-local and 303 * link-local scope IDs, and use interface indices as the 304 * zone IDs assuming a one-to-one mapping between interfaces 305 * and links. 306 */ 307 s = pserialize_read_enter(); 308 ifp = if_byindex(zoneid); 309 if (ifp == NULL) { 310 pserialize_read_exit(s); 311 return ENXIO; 312 } 313 pserialize_read_exit(s); 314 315 /* XXX assignment to 16bit from 32bit variable */ 316 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 317 318 sin6->sin6_scope_id = 0; 319 } 320 321 return 0; 322 } 323 324 struct sockaddr * 325 sockaddr_in6_externalize(struct sockaddr *dst, socklen_t socklen, 326 const struct sockaddr *src) 327 { 328 struct sockaddr_in6 *sin6; 329 330 sin6 = satosin6(sockaddr_copy(dst, socklen, src)); 331 332 if (sin6 == NULL || sa6_recoverscope(sin6) != 0) 333 return NULL; 334 335 return dst; 336 } 337 338 /* 339 * generate standard sockaddr_in6 from embedded form. 340 */ 341 int 342 sa6_recoverscope(struct sockaddr_in6 *sin6) 343 { 344 uint32_t zoneid; 345 char ip6buf[INET6_ADDRSTRLEN]; 346 347 if (sin6->sin6_scope_id != 0) { 348 log(LOG_NOTICE, 349 "%s: assumption failure (non 0 ID): %s%%%d\n", __func__, 350 IN6_PRINT(ip6buf, &sin6->sin6_addr), sin6->sin6_scope_id); 351 /* XXX: proceed anyway... */ 352 } 353 if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 354 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr)) { 355 /* 356 * KAME assumption: link id == interface id 357 */ 358 zoneid = ntohs(sin6->sin6_addr.s6_addr16[1]); 359 if (zoneid) { 360 int s = pserialize_read_enter(); 361 if (!if_byindex(zoneid)) { 362 pserialize_read_exit(s); 363 return ENXIO; 364 } 365 pserialize_read_exit(s); 366 sin6->sin6_addr.s6_addr16[1] = 0; 367 sin6->sin6_scope_id = zoneid; 368 } 369 } 370 371 return 0; 372 } 373 374 int 375 in6_setzoneid(struct in6_addr *in6, uint32_t zoneid) 376 { 377 if (IN6_IS_SCOPE_EMBEDDABLE(in6)) 378 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 379 380 return 0; 381 } 382 383 /* 384 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 385 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 386 * in the in6_addr structure, in6 will be modified. 387 */ 388 int 389 in6_setscope(struct in6_addr *in6, const struct ifnet *ifp, uint32_t *ret_id) 390 { 391 int scope; 392 uint32_t zoneid = 0; 393 const struct scope6_id *sid = SID(ifp); 394 395 if (sid == NULL) { 396 log(LOG_NOTICE, "%s: no scope id for %s\n", __func__, 397 if_name(ifp)); 398 return EINVAL; 399 } 400 401 /* 402 * special case: the loopback address can only belong to a loopback 403 * interface. 404 */ 405 if (IN6_IS_ADDR_LOOPBACK(in6)) { 406 if (!(ifp->if_flags & IFF_LOOPBACK)) { 407 char ip6buf[INET6_ADDRSTRLEN]; 408 log(LOG_NOTICE, "%s: can't set scope for not loopback " 409 "interface %s and loopback address %s\n", 410 __func__, if_name(ifp), IN6_PRINT(ip6buf, in6)); 411 return EINVAL; 412 } else { 413 if (ret_id != NULL) 414 *ret_id = 0; /* there's no ambiguity */ 415 return 0; 416 } 417 } 418 419 scope = in6_addrscope(in6); 420 421 switch (scope) { 422 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ 423 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; 424 break; 425 426 case IPV6_ADDR_SCOPE_LINKLOCAL: 427 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; 428 break; 429 430 case IPV6_ADDR_SCOPE_SITELOCAL: 431 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; 432 break; 433 434 case IPV6_ADDR_SCOPE_ORGLOCAL: 435 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; 436 break; 437 438 default: 439 zoneid = 0; /* XXX: treat as global. */ 440 break; 441 } 442 443 if (ret_id != NULL) 444 *ret_id = zoneid; 445 446 return in6_setzoneid(in6, zoneid); 447 } 448 449 const char * 450 in6_getscopename(const struct in6_addr *addr) 451 { 452 switch (in6_addrscope(addr)) { 453 case IPV6_ADDR_SCOPE_INTFACELOCAL: 454 return "interface"; 455 #if IPV6_ADDR_SCOPE_INTFACELOCAL != IPV6_ADDR_SCOPE_NODELOCAL 456 case IPV6_ADDR_SCOPE_NODELOCAL: 457 return "node"; 458 #endif 459 case IPV6_ADDR_SCOPE_LINKLOCAL: 460 return "link"; 461 case IPV6_ADDR_SCOPE_SITELOCAL: 462 return "site"; 463 case IPV6_ADDR_SCOPE_ORGLOCAL: 464 return "organization"; 465 case IPV6_ADDR_SCOPE_GLOBAL: 466 return "global"; 467 default: 468 return "unknown"; 469 } 470 } 471 472 /* 473 * Just clear the embedded scope identifier. Return 0 if the original address 474 * is intact; return non 0 if the address is modified. 475 */ 476 int 477 in6_clearscope(struct in6_addr *in6) 478 { 479 int modified = 0; 480 481 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 482 if (in6->s6_addr16[1] != 0) 483 modified = 1; 484 in6->s6_addr16[1] = 0; 485 } 486 487 return modified; 488 } 489