1 /* $NetBSD: scope6.c,v 1.17 2017/01/16 15:44:47 christos 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 1.17 2017/01/16 15:44:47 christos 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 46 #include <netinet/in.h> 47 48 #include <netinet6/in6_var.h> 49 #include <netinet6/scope6_var.h> 50 51 #ifdef ENABLE_DEFAULT_SCOPE 52 int ip6_use_defzone = 1; 53 #else 54 int ip6_use_defzone = 0; 55 #endif 56 57 static struct scope6_id sid_default; 58 #define SID(ifp) \ 59 ((ifp)->if_afdata[AF_INET6] == NULL ? NULL : \ 60 ((struct in6_ifextra *)(ifp)->if_afdata[AF_INET6])->scope6_id) 61 62 void 63 scope6_init(void) 64 { 65 66 memset(&sid_default, 0, sizeof(sid_default)); 67 } 68 69 struct scope6_id * 70 scope6_ifattach(struct ifnet *ifp) 71 { 72 struct scope6_id *sid; 73 74 sid = (struct scope6_id *)malloc(sizeof(*sid), M_IFADDR, M_WAITOK); 75 memset(sid, 0, sizeof(*sid)); 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 } 192 193 194 if (addr->s6_addr[0] == 0xff) { 195 scope = addr->s6_addr[1] & 0x0f; 196 197 /* 198 * due to other scope such as reserved, 199 * return scope doesn't work. 200 */ 201 switch (scope) { 202 case IPV6_ADDR_SCOPE_INTFACELOCAL: 203 return IPV6_ADDR_SCOPE_INTFACELOCAL; 204 case IPV6_ADDR_SCOPE_LINKLOCAL: 205 return IPV6_ADDR_SCOPE_LINKLOCAL; 206 case IPV6_ADDR_SCOPE_SITELOCAL: 207 return IPV6_ADDR_SCOPE_SITELOCAL; 208 default: 209 return IPV6_ADDR_SCOPE_GLOBAL; 210 } 211 } 212 213 if (memcmp(&in6addr_loopback, addr, sizeof(*addr) - 1) == 0) { 214 if (addr->s6_addr[15] == 1) /* loopback */ 215 return IPV6_ADDR_SCOPE_LINKLOCAL; 216 if (addr->s6_addr[15] == 0) { 217 /* 218 * Regard the unspecified addresses as global, 219 * since it has no ambiguity. 220 * XXX: not sure if it's correct... 221 */ 222 return IPV6_ADDR_SCOPE_GLOBAL; 223 } 224 } 225 226 return IPV6_ADDR_SCOPE_GLOBAL; 227 } 228 229 /* note that ifp argument might be NULL */ 230 void 231 scope6_setdefault(struct ifnet *ifp) 232 { 233 234 /* 235 * Currently, this function just sets the default "interfaces" 236 * and "links" according to the given interface. 237 * We might eventually have to separate the notion of "link" from 238 * "interface" and provide a user interface to set the default. 239 */ 240 if (ifp) { 241 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 242 ifp->if_index; 243 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 244 ifp->if_index; 245 } else { 246 sid_default.s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL] = 0; 247 sid_default.s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL] = 0; 248 } 249 } 250 251 int 252 scope6_get_default(struct scope6_id *idlist) 253 { 254 255 *idlist = sid_default; 256 257 return (0); 258 } 259 260 uint32_t 261 scope6_addr2default(const struct in6_addr *addr) 262 { 263 uint32_t id; 264 265 /* 266 * special case: The loopback address should be considered as 267 * link-local, but there's no ambiguity in the syntax. 268 */ 269 if (IN6_IS_ADDR_LOOPBACK(addr)) 270 return (0); 271 272 /* 273 * XXX: 32-bit read is atomic on all our platforms, is it OK 274 * not to lock here? 275 */ 276 id = sid_default.s6id_list[in6_addrscope(addr)]; 277 278 return (id); 279 } 280 281 /* 282 * Validate the specified scope zone ID in the sin6_scope_id field. If the ID 283 * is unspecified (=0), needs to be specified, and the default zone ID can be 284 * used, the default value will be used. 285 * This routine then generates the kernel-internal form: if the address scope 286 * of is interface-local or link-local, embed the interface index in the 287 * address. 288 */ 289 int 290 sa6_embedscope(struct sockaddr_in6 *sin6, int defaultok) 291 { 292 struct ifnet *ifp; 293 uint32_t zoneid; 294 295 if ((zoneid = sin6->sin6_scope_id) == 0 && defaultok) 296 zoneid = scope6_addr2default(&sin6->sin6_addr); 297 298 if (zoneid != 0 && 299 (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr) || 300 IN6_IS_ADDR_MC_INTFACELOCAL(&sin6->sin6_addr))) { 301 int s; 302 /* 303 * At this moment, we only check interface-local and 304 * link-local scope IDs, and use interface indices as the 305 * zone IDs assuming a one-to-one mapping between interfaces 306 * and links. 307 */ 308 s = pserialize_read_enter(); 309 ifp = if_byindex(zoneid); 310 if (ifp == NULL) { 311 pserialize_read_exit(s); 312 return (ENXIO); 313 } 314 pserialize_read_exit(s); 315 316 /* XXX assignment to 16bit from 32bit variable */ 317 sin6->sin6_addr.s6_addr16[1] = htons(zoneid & 0xffff); 318 319 sin6->sin6_scope_id = 0; 320 } 321 322 return 0; 323 } 324 325 struct sockaddr * 326 sockaddr_in6_externalize(struct sockaddr *dst, socklen_t socklen, 327 const struct sockaddr *src) 328 { 329 struct sockaddr_in6 *sin6; 330 331 sin6 = satosin6(sockaddr_copy(dst, socklen, src)); 332 333 if (sin6 == NULL || sa6_recoverscope(sin6) != 0) 334 return NULL; 335 336 return dst; 337 } 338 339 /* 340 * generate standard sockaddr_in6 from embedded form. 341 */ 342 int 343 sa6_recoverscope(struct sockaddr_in6 *sin6) 344 { 345 uint32_t zoneid; 346 char ip6buf[INET6_ADDRSTRLEN]; 347 348 if (sin6->sin6_scope_id != 0) { 349 log(LOG_NOTICE, 350 "sa6_recoverscope: assumption failure (non 0 ID): %s%%%d\n", 351 IN6_PRINT(ip6buf, &sin6->sin6_addr), sin6->sin6_scope_id); 352 /* XXX: proceed anyway... */ 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 int s = pserialize_read_enter(); 362 if (!if_byindex(zoneid)) { 363 pserialize_read_exit(s); 364 return (ENXIO); 365 } 366 pserialize_read_exit(s); 367 sin6->sin6_addr.s6_addr16[1] = 0; 368 sin6->sin6_scope_id = zoneid; 369 } 370 } 371 372 return 0; 373 } 374 375 int 376 in6_setzoneid(struct in6_addr *in6, uint32_t zoneid) 377 { 378 if (IN6_IS_SCOPE_EMBEDDABLE(in6)) 379 in6->s6_addr16[1] = htons(zoneid & 0xffff); /* XXX */ 380 381 return 0; 382 } 383 384 /* 385 * Determine the appropriate scope zone ID for in6 and ifp. If ret_id is 386 * non NULL, it is set to the zone ID. If the zone ID needs to be embedded 387 * in the in6_addr structure, in6 will be modified. 388 */ 389 int 390 in6_setscope(struct in6_addr *in6, const struct ifnet *ifp, uint32_t *ret_id) 391 { 392 int scope; 393 uint32_t zoneid = 0; 394 const struct scope6_id *sid = SID(ifp); 395 396 if (sid == NULL) 397 return EINVAL; 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 if (ret_id != NULL) 408 *ret_id = 0; /* there's no ambiguity */ 409 return (0); 410 } 411 } 412 413 scope = in6_addrscope(in6); 414 415 switch (scope) { 416 case IPV6_ADDR_SCOPE_INTFACELOCAL: /* should be interface index */ 417 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_INTFACELOCAL]; 418 break; 419 420 case IPV6_ADDR_SCOPE_LINKLOCAL: 421 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_LINKLOCAL]; 422 break; 423 424 case IPV6_ADDR_SCOPE_SITELOCAL: 425 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_SITELOCAL]; 426 break; 427 428 case IPV6_ADDR_SCOPE_ORGLOCAL: 429 zoneid = sid->s6id_list[IPV6_ADDR_SCOPE_ORGLOCAL]; 430 break; 431 432 default: 433 zoneid = 0; /* XXX: treat as global. */ 434 break; 435 } 436 437 if (ret_id != NULL) 438 *ret_id = zoneid; 439 440 return in6_setzoneid(in6, zoneid); 441 } 442 443 const char * 444 in6_getscopename(const struct in6_addr *addr) 445 { 446 switch (in6_addrscope(addr)) { 447 case IPV6_ADDR_SCOPE_INTFACELOCAL: return "interface"; 448 #if IPV6_ADDR_SCOPE_INTFACELOCAL != IPV6_ADDR_SCOPE_NODELOCAL 449 case IPV6_ADDR_SCOPE_NODELOCAL: return "node"; 450 #endif 451 case IPV6_ADDR_SCOPE_LINKLOCAL: return "link"; 452 case IPV6_ADDR_SCOPE_SITELOCAL: return "site"; 453 case IPV6_ADDR_SCOPE_ORGLOCAL: return "organization"; 454 case IPV6_ADDR_SCOPE_GLOBAL: return "global"; 455 default: return "unknown"; 456 } 457 } 458 459 /* 460 * Just clear the embedded scope identifier. Return 0 if the original address 461 * is intact; return non 0 if the address is modified. 462 */ 463 int 464 in6_clearscope(struct in6_addr *in6) 465 { 466 int modified = 0; 467 468 if (IN6_IS_SCOPE_LINKLOCAL(in6) || IN6_IS_ADDR_MC_INTFACELOCAL(in6)) { 469 if (in6->s6_addr16[1] != 0) 470 modified = 1; 471 in6->s6_addr16[1] = 0; 472 } 473 474 return (modified); 475 } 476