in6_src.c revision 1.5.2.7
1 /* $NetBSD: in6_src.c,v 1.5.2.7 2002/02/28 04:15:14 nathanw Exp $ */ 2 /* $KAME: in6_src.c,v 1.36 2001/02/06 04:08:17 itojun Exp $ */ 3 4 /* 5 * Copyright (C) 1995, 1996, 1997, and 1998 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 /* 34 * Copyright (c) 1982, 1986, 1991, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 66 */ 67 68 #include <sys/cdefs.h> 69 __KERNEL_RCSID(0, "$NetBSD: in6_src.c,v 1.5.2.7 2002/02/28 04:15:14 nathanw Exp $"); 70 71 #include "opt_inet.h" 72 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/malloc.h> 76 #include <sys/mbuf.h> 77 #include <sys/protosw.h> 78 #include <sys/socket.h> 79 #include <sys/socketvar.h> 80 #include <sys/ioctl.h> 81 #include <sys/errno.h> 82 #include <sys/time.h> 83 #include <sys/lwp.h> 84 #include <sys/proc.h> 85 86 #include <net/if.h> 87 #include <net/route.h> 88 89 #include <netinet/in.h> 90 #include <netinet/in_var.h> 91 #include <netinet/in_systm.h> 92 #include <netinet/ip.h> 93 #include <netinet/in_pcb.h> 94 #include <netinet6/in6_var.h> 95 #include <netinet/ip6.h> 96 #include <netinet6/in6_pcb.h> 97 #include <netinet6/ip6_var.h> 98 #include <netinet6/nd6.h> 99 #ifdef ENABLE_DEFAULT_SCOPE 100 #include <netinet6/scope6_var.h> 101 #endif 102 103 #include <net/net_osdep.h> 104 105 #include "loop.h" 106 extern struct ifnet loif[NLOOP]; 107 108 /* 109 * Return an IPv6 address, which is the most appropriate for a given 110 * destination and user specified options. 111 * If necessary, this function lookups the routing table and returns 112 * an entry to the caller for later use. 113 */ 114 struct in6_addr * 115 in6_selectsrc(dstsock, opts, mopts, ro, laddr, errorp) 116 struct sockaddr_in6 *dstsock; 117 struct ip6_pktopts *opts; 118 struct ip6_moptions *mopts; 119 struct route_in6 *ro; 120 struct in6_addr *laddr; 121 int *errorp; 122 { 123 struct in6_addr *dst; 124 struct in6_ifaddr *ia6 = 0; 125 struct in6_pktinfo *pi = NULL; 126 127 dst = &dstsock->sin6_addr; 128 *errorp = 0; 129 130 /* 131 * If the source address is explicitly specified by the caller, 132 * use it. 133 */ 134 if (opts && (pi = opts->ip6po_pktinfo) && 135 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) 136 return(&pi->ipi6_addr); 137 138 /* 139 * If the source address is not specified but the socket(if any) 140 * is already bound, use the bound address. 141 */ 142 if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) 143 return(laddr); 144 145 /* 146 * If the caller doesn't specify the source address but 147 * the outgoing interface, use an address associated with 148 * the interface. 149 */ 150 if (pi && pi->ipi6_ifindex) { 151 /* XXX boundary check is assumed to be already done. */ 152 ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex], 153 dst); 154 if (ia6 == 0) { 155 *errorp = EADDRNOTAVAIL; 156 return(0); 157 } 158 return(&satosin6(&ia6->ia_addr)->sin6_addr); 159 } 160 161 /* 162 * If the destination address is a link-local unicast address or 163 * a multicast address, and if the outgoing interface is specified 164 * by the sin6_scope_id filed, use an address associated with the 165 * interface. 166 * XXX: We're now trying to define more specific semantics of 167 * sin6_scope_id field, so this part will be rewritten in 168 * the near future. 169 */ 170 if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) && 171 dstsock->sin6_scope_id) { 172 /* 173 * I'm not sure if boundary check for scope_id is done 174 * somewhere... 175 */ 176 if (dstsock->sin6_scope_id < 0 || 177 if_index < dstsock->sin6_scope_id) { 178 *errorp = ENXIO; /* XXX: better error? */ 179 return(0); 180 } 181 ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id], 182 dst); 183 if (ia6 == 0) { 184 *errorp = EADDRNOTAVAIL; 185 return(0); 186 } 187 return(&satosin6(&ia6->ia_addr)->sin6_addr); 188 } 189 190 /* 191 * If the destination address is a multicast address and 192 * the outgoing interface for the address is specified 193 * by the caller, use an address associated with the interface. 194 * There is a sanity check here; if the destination has node-local 195 * scope, the outgoing interfacde should be a loopback address. 196 * Even if the outgoing interface is not specified, we also 197 * choose a loopback interface as the outgoing interface. 198 */ 199 if (IN6_IS_ADDR_MULTICAST(dst)) { 200 struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL; 201 202 if (ifp == NULL && IN6_IS_ADDR_MC_NODELOCAL(dst)) { 203 ifp = &loif[0]; 204 } 205 206 if (ifp) { 207 ia6 = in6_ifawithscope(ifp, dst); 208 if (ia6 == 0) { 209 *errorp = EADDRNOTAVAIL; 210 return(0); 211 } 212 return(&satosin6(&ia6->ia_addr)->sin6_addr); 213 } 214 } 215 216 /* 217 * If the next hop address for the packet is specified 218 * by caller, use an address associated with the route 219 * to the next hop. 220 */ 221 { 222 struct sockaddr_in6 *sin6_next; 223 struct rtentry *rt; 224 225 if (opts && opts->ip6po_nexthop) { 226 sin6_next = satosin6(opts->ip6po_nexthop); 227 rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); 228 if (rt) { 229 ia6 = in6_ifawithscope(rt->rt_ifp, dst); 230 if (ia6 == 0) 231 ia6 = ifatoia6(rt->rt_ifa); 232 } 233 if (ia6 == 0) { 234 *errorp = EADDRNOTAVAIL; 235 return(0); 236 } 237 return(&satosin6(&ia6->ia_addr)->sin6_addr); 238 } 239 } 240 241 /* 242 * If route is known or can be allocated now, 243 * our src addr is taken from the i/f, else punt. 244 * Note that we should check the address family of the 245 * cached destination, in case of sharing the cache with IPv4. 246 */ 247 if (ro) { 248 if (ro->ro_rt && 249 (ro->ro_dst.sin6_family != AF_INET6 || 250 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst))) { 251 RTFREE(ro->ro_rt); 252 ro->ro_rt = (struct rtentry *)0; 253 } 254 if (ro->ro_rt == (struct rtentry *)0 || 255 ro->ro_rt->rt_ifp == (struct ifnet *)0) { 256 struct sockaddr_in6 *sa6; 257 258 /* No route yet, so try to acquire one */ 259 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 260 sa6 = (struct sockaddr_in6 *)&ro->ro_dst; 261 sa6->sin6_family = AF_INET6; 262 sa6->sin6_len = sizeof(struct sockaddr_in6); 263 sa6->sin6_addr = *dst; 264 sa6->sin6_scope_id = dstsock->sin6_scope_id; 265 if (IN6_IS_ADDR_MULTICAST(dst)) { 266 ro->ro_rt = rtalloc1(&((struct route *)ro) 267 ->ro_dst, 0); 268 } else { 269 rtalloc((struct route *)ro); 270 } 271 } 272 273 /* 274 * in_pcbconnect() checks out IFF_LOOPBACK to skip using 275 * the address. But we don't know why it does so. 276 * It is necessary to ensure the scope even for lo0 277 * so doesn't check out IFF_LOOPBACK. 278 */ 279 280 if (ro->ro_rt) { 281 ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst); 282 if (ia6 == 0) /* xxx scope error ?*/ 283 ia6 = ifatoia6(ro->ro_rt->rt_ifa); 284 } 285 #if 0 286 /* 287 * xxx The followings are necessary? (kazu) 288 * I don't think so. 289 * It's for SO_DONTROUTE option in IPv4.(jinmei) 290 */ 291 if (ia6 == 0) { 292 struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; 293 294 sin6->sin6_addr = *dst; 295 296 ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); 297 if (ia6 == 0) 298 ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); 299 if (ia6 == 0) 300 return(0); 301 return(&satosin6(&ia6->ia_addr)->sin6_addr); 302 } 303 #endif /* 0 */ 304 if (ia6 == 0) { 305 *errorp = EHOSTUNREACH; /* no route */ 306 return(0); 307 } 308 return(&satosin6(&ia6->ia_addr)->sin6_addr); 309 } 310 311 *errorp = EADDRNOTAVAIL; 312 return(0); 313 } 314 315 /* 316 * Default hop limit selection. The precedence is as follows: 317 * 1. Hoplimit value specified via ioctl. 318 * 2. (If the outgoing interface is detected) the current 319 * hop limit of the interface specified by router advertisement. 320 * 3. The system default hoplimit. 321 */ 322 int 323 in6_selecthlim(in6p, ifp) 324 struct in6pcb *in6p; 325 struct ifnet *ifp; 326 { 327 if (in6p && in6p->in6p_hops >= 0) 328 return(in6p->in6p_hops); 329 else if (ifp) 330 return(nd_ifinfo[ifp->if_index].chlim); 331 else 332 return(ip6_defhlim); 333 } 334 335 /* 336 * Find an empty port and set it to the specified PCB. 337 */ 338 int 339 in6_pcbsetport(laddr, in6p) 340 struct in6_addr *laddr; 341 struct in6pcb *in6p; 342 { 343 struct socket *so = in6p->in6p_socket; 344 struct in6pcb *head = in6p->in6p_head; 345 u_int16_t last_port, lport = 0; 346 int wild = 0; 347 void *t; 348 u_int16_t min, max; 349 350 /* XXX: this is redundant when called from in6_pcbbind */ 351 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 && 352 ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 || 353 (so->so_options & SO_ACCEPTCONN) == 0)) 354 wild = IN6PLOOKUP_WILDCARD; 355 356 if (in6p->in6p_flags & IN6P_LOWPORT) { 357 #ifndef IPNOPRIVPORTS 358 struct proc *p = (curproc ? curproc->l_proc : 0);/* XXX */ 359 360 if (p == 0 || (suser(p->p_ucred, &p->p_acflag) != 0)) 361 return (EACCES); 362 #endif 363 min = ip6_lowportmin; 364 max = ip6_lowportmax; 365 } else { 366 min = ip6_anonportmin; 367 max = ip6_anonportmax; 368 } 369 370 /* value out of range */ 371 if (head->in6p_lport < min) 372 head->in6p_lport = min; 373 else if (head->in6p_lport > max) 374 head->in6p_lport = min; 375 last_port = head->in6p_lport; 376 goto startover; /*to randomize*/ 377 for (;;) { 378 lport = htons(head->in6p_lport); 379 if (IN6_IS_ADDR_V4MAPPED(laddr)) { 380 #if 0 381 t = in_pcblookup_bind(&tcbtable, 382 (struct in_addr *)&in6p->in6p_laddr.s6_addr32[3], 383 lport); 384 #else 385 t = NULL; 386 #endif 387 } else { 388 t = in6_pcblookup(head, &zeroin6_addr, 0, laddr, 389 lport, wild); 390 } 391 if (t == 0) 392 break; 393 startover: 394 if (head->in6p_lport >= max) 395 head->in6p_lport = min; 396 else 397 head->in6p_lport++; 398 if (head->in6p_lport == last_port) 399 return (EADDRINUSE); 400 } 401 402 in6p->in6p_lport = lport; 403 return(0); /* success */ 404 } 405 406 /* 407 * generate kernel-internal form (scopeid embedded into s6_addr16[1]). 408 * If the address scope of is link-local, embed the interface index in the 409 * address. The routine determines our precedence 410 * between advanced API scope/interface specification and basic API 411 * specification. 412 * 413 * this function should be nuked in the future, when we get rid of 414 * embedded scopeid thing. 415 * 416 * XXX actually, it is over-specification to return ifp against sin6_scope_id. 417 * there can be multiple interfaces that belong to a particular scope zone 418 * (in specification, we have 1:N mapping between a scope zone and interfaces). 419 * we may want to change the function to return something other than ifp. 420 */ 421 int 422 in6_embedscope(in6, sin6, in6p, ifpp) 423 struct in6_addr *in6; 424 const struct sockaddr_in6 *sin6; 425 struct in6pcb *in6p; 426 struct ifnet **ifpp; 427 { 428 struct ifnet *ifp = NULL; 429 u_int32_t scopeid; 430 431 *in6 = sin6->sin6_addr; 432 scopeid = sin6->sin6_scope_id; 433 if (ifpp) 434 *ifpp = NULL; 435 436 /* 437 * don't try to read sin6->sin6_addr beyond here, since the caller may 438 * ask us to overwrite existing sockaddr_in6 439 */ 440 441 #ifdef ENABLE_DEFAULT_SCOPE 442 if (scopeid == 0) 443 scopeid = scope6_addr2default(in6); 444 #endif 445 446 if (IN6_IS_SCOPE_LINKLOCAL(in6)) { 447 struct in6_pktinfo *pi; 448 449 /* 450 * KAME assumption: link id == interface id 451 */ 452 453 if (in6p && in6p->in6p_outputopts && 454 (pi = in6p->in6p_outputopts->ip6po_pktinfo) && 455 pi->ipi6_ifindex) { 456 ifp = ifindex2ifnet[pi->ipi6_ifindex]; 457 in6->s6_addr16[1] = htons(pi->ipi6_ifindex); 458 } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && 459 in6p->in6p_moptions && 460 in6p->in6p_moptions->im6o_multicast_ifp) { 461 ifp = in6p->in6p_moptions->im6o_multicast_ifp; 462 in6->s6_addr16[1] = htons(ifp->if_index); 463 } else if (scopeid) { 464 /* boundary check */ 465 if (scopeid < 0 || if_index < scopeid) 466 return ENXIO; /* XXX EINVAL? */ 467 ifp = ifindex2ifnet[scopeid]; 468 /* XXX assignment to 16bit from 32bit variable */ 469 in6->s6_addr16[1] = htons(scopeid & 0xffff); 470 } 471 472 if (ifpp) 473 *ifpp = ifp; 474 } 475 476 return 0; 477 } 478 479 /* 480 * generate standard sockaddr_in6 from embedded form. 481 * touches sin6_addr and sin6_scope_id only. 482 * 483 * this function should be nuked in the future, when we get rid of 484 * embedded scopeid thing. 485 */ 486 int 487 in6_recoverscope(sin6, in6, ifp) 488 struct sockaddr_in6 *sin6; 489 const struct in6_addr *in6; 490 struct ifnet *ifp; 491 { 492 u_int32_t scopeid; 493 494 sin6->sin6_addr = *in6; 495 496 /* 497 * don't try to read *in6 beyond here, since the caller may 498 * ask us to overwrite existing sockaddr_in6 499 */ 500 501 sin6->sin6_scope_id = 0; 502 if (IN6_IS_SCOPE_LINKLOCAL(in6)) { 503 /* 504 * KAME assumption: link id == interface id 505 */ 506 scopeid = ntohs(sin6->sin6_addr.s6_addr16[1]); 507 if (scopeid) { 508 /* sanity check */ 509 if (scopeid < 0 || if_index < scopeid) 510 return ENXIO; 511 if (ifp && ifp->if_index != scopeid) 512 return ENXIO; 513 sin6->sin6_addr.s6_addr16[1] = 0; 514 sin6->sin6_scope_id = scopeid; 515 } 516 } 517 518 return 0; 519 } 520 521 /* 522 * just clear the embedded scope identifer. 523 * XXX: currently used for bsdi4 only as a supplement function. 524 */ 525 void 526 in6_clearscope(addr) 527 struct in6_addr *addr; 528 { 529 if (IN6_IS_SCOPE_LINKLOCAL(addr)) 530 addr->s6_addr16[1] = 0; 531 } 532
Indexes created Sat Oct 11 16:09:52 GMT 2025