1 /* $NetBSD: in6_src.c,v 1.1 2000/06/03 14:36:36 itojun Exp $ */ 2 /* $KAME: in6_src.c,v 1.15 2000/05/30 10:16:24 jinmei 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 "opt_inet.h" 69 70 #include <sys/param.h> 71 #include <sys/systm.h> 72 #include <sys/malloc.h> 73 #include <sys/mbuf.h> 74 #include <sys/protosw.h> 75 #include <sys/socket.h> 76 #include <sys/socketvar.h> 77 #include <sys/ioctl.h> 78 #include <sys/errno.h> 79 #include <sys/time.h> 80 #include <sys/proc.h> 81 82 #include <net/if.h> 83 #include <net/route.h> 84 85 #include <netinet/in.h> 86 #include <netinet/in_var.h> 87 #include <netinet/in_systm.h> 88 #include <netinet/ip.h> 89 #include <netinet/in_pcb.h> 90 #include <netinet6/in6_var.h> 91 #include <netinet/ip6.h> 92 #include <netinet6/in6_pcb.h> 93 #include <netinet6/ip6_var.h> 94 #include <netinet6/nd6.h> 95 96 #include <net/net_osdep.h> 97 98 #include "loop.h" 99 extern struct ifnet loif[NLOOP]; 100 101 /* 102 * Return an IPv6 address, which is the most appropriate for given 103 * destination and user specified options. 104 * If necessary, this function lookups the routing table and return 105 * an entry to the caller for later use. 106 */ 107 struct in6_addr * 108 in6_selectsrc(dstsock, opts, mopts, ro, laddr, errorp) 109 struct sockaddr_in6 *dstsock; 110 struct ip6_pktopts *opts; 111 struct ip6_moptions *mopts; 112 struct route_in6 *ro; 113 struct in6_addr *laddr; 114 int *errorp; 115 { 116 struct in6_addr *dst; 117 struct in6_ifaddr *ia6 = 0; 118 struct in6_pktinfo *pi = NULL; 119 120 dst = &dstsock->sin6_addr; 121 *errorp = 0; 122 123 /* 124 * If the source address is explicitly specified by the caller, 125 * use it. 126 */ 127 if (opts && (pi = opts->ip6po_pktinfo) && 128 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) 129 return(&pi->ipi6_addr); 130 131 /* 132 * If the source address is not specified but the socket(if any) 133 * is already bound, use the bound address. 134 */ 135 if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) 136 return(laddr); 137 138 /* 139 * If the caller doesn't specify the source address but 140 * the outgoing interface, use an address associated with 141 * the interface. 142 */ 143 if (pi && pi->ipi6_ifindex) { 144 /* XXX boundary check is assumed to be already done. */ 145 ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex], 146 dst); 147 if (ia6 == 0) { 148 *errorp = EADDRNOTAVAIL; 149 return(0); 150 } 151 return(&satosin6(&ia6->ia_addr)->sin6_addr); 152 } 153 154 /* 155 * If the destination address is a link-local unicast address or 156 * a multicast address, and if the outgoing interface is specified 157 * by the sin6_scope_id filed, use an address associated with the 158 * interface. 159 * XXX: We're now trying to define more specific semantics of 160 * sin6_scope_id field, so this part will be rewritten in 161 * the near future. 162 */ 163 if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) && 164 dstsock->sin6_scope_id) { 165 /* 166 * I'm not sure if boundary check for scope_id is done 167 * somewhere... 168 */ 169 if (dstsock->sin6_scope_id < 0 || 170 if_index < dstsock->sin6_scope_id) { 171 *errorp = ENXIO; /* XXX: better error? */ 172 return(0); 173 } 174 ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id], 175 dst); 176 if (ia6 == 0) { 177 *errorp = EADDRNOTAVAIL; 178 return(0); 179 } 180 return(&satosin6(&ia6->ia_addr)->sin6_addr); 181 } 182 183 /* 184 * If the destination address is a multicast address and 185 * the outgoing interface for the address is specified 186 * by the caller, use an address associated with the interface. 187 * There is a sanity check here; if the destination has node-local 188 * scope, the outgoing interfacde should be a loopback address. 189 * Even if the outgoing interface is not specified, we also 190 * choose a loopback interface as the outgoing interface. 191 */ 192 if (IN6_IS_ADDR_MULTICAST(dst)) { 193 struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL; 194 195 if (ifp == NULL && IN6_IS_ADDR_MC_NODELOCAL(dst)) { 196 ifp = &loif[0]; 197 } 198 199 if (ifp) { 200 ia6 = in6_ifawithscope(ifp, dst); 201 if (ia6 == 0) { 202 *errorp = EADDRNOTAVAIL; 203 return(0); 204 } 205 return(&satosin6(&ia6->ia_addr)->sin6_addr); 206 } 207 } 208 209 /* 210 * If the next hop address for the packet is specified 211 * by caller, use an address associated with the route 212 * to the next hop. 213 */ 214 { 215 struct sockaddr_in6 *sin6_next; 216 struct rtentry *rt; 217 218 if (opts && opts->ip6po_nexthop) { 219 sin6_next = satosin6(opts->ip6po_nexthop); 220 rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); 221 if (rt) { 222 ia6 = in6_ifawithscope(rt->rt_ifp, dst); 223 if (ia6 == 0) 224 ia6 = ifatoia6(rt->rt_ifa); 225 } 226 if (ia6 == 0) { 227 *errorp = EADDRNOTAVAIL; 228 return(0); 229 } 230 return(&satosin6(&ia6->ia_addr)->sin6_addr); 231 } 232 } 233 234 /* 235 * If route is known or can be allocated now, 236 * our src addr is taken from the i/f, else punt. 237 */ 238 if (ro) { 239 if (ro->ro_rt && 240 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst)) { 241 RTFREE(ro->ro_rt); 242 ro->ro_rt = (struct rtentry *)0; 243 } 244 if (ro->ro_rt == (struct rtentry *)0 || 245 ro->ro_rt->rt_ifp == (struct ifnet *)0) { 246 /* No route yet, so try to acquire one */ 247 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 248 ro->ro_dst.sin6_family = AF_INET6; 249 ro->ro_dst.sin6_len = sizeof(struct sockaddr_in6); 250 ro->ro_dst.sin6_addr = *dst; 251 ro->ro_dst.sin6_scope_id = dstsock->sin6_scope_id; 252 if (IN6_IS_ADDR_MULTICAST(dst)) { 253 ro->ro_rt = rtalloc1(&((struct route *)ro) 254 ->ro_dst, 0); 255 } else { 256 rtalloc((struct route *)ro); 257 } 258 } 259 260 /* 261 * in_pcbconnect() checks out IFF_LOOPBACK to skip using 262 * the address. But we don't know why it does so. 263 * It is necessary to ensure the scope even for lo0 264 * so doesn't check out IFF_LOOPBACK. 265 */ 266 267 if (ro->ro_rt) { 268 ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst); 269 if (ia6 == 0) /* xxx scope error ?*/ 270 ia6 = ifatoia6(ro->ro_rt->rt_ifa); 271 } 272 #if 0 273 /* 274 * xxx The followings are necessary? (kazu) 275 * I don't think so. 276 * It's for SO_DONTROUTE option in IPv4.(jinmei) 277 */ 278 if (ia6 == 0) { 279 struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; 280 281 sin6->sin6_addr = *dst; 282 283 ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); 284 if (ia6 == 0) 285 ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); 286 if (ia6 == 0) 287 return(0); 288 return(&satosin6(&ia6->ia_addr)->sin6_addr); 289 } 290 #endif /* 0 */ 291 if (ia6 == 0) { 292 *errorp = EHOSTUNREACH; /* no route */ 293 return(0); 294 } 295 return(&satosin6(&ia6->ia_addr)->sin6_addr); 296 } 297 298 *errorp = EADDRNOTAVAIL; 299 return(0); 300 } 301 302 /* 303 * Default hop limit selection. The precedence is as follows: 304 * 1. Hoplimit value specified via ioctl. 305 * 2. (If the outgoing interface is detected) the current 306 * hop limit of the interface specified by router advertisement. 307 * 3. The system default hoplimit. 308 */ 309 int 310 in6_selecthlim(in6p, ifp) 311 struct in6pcb *in6p; 312 struct ifnet *ifp; 313 { 314 if (in6p && in6p->in6p_hops >= 0) 315 return(in6p->in6p_hops); 316 else if (ifp) 317 return(nd_ifinfo[ifp->if_index].chlim); 318 else 319 return(ip6_defhlim); 320 } 321 322 /* 323 * Find an empty port and set it to the specified PCB. 324 */ 325 int 326 in6_pcbsetport(laddr, in6p) 327 struct in6_addr *laddr; 328 struct in6pcb *in6p; 329 { 330 struct socket *so = in6p->in6p_socket; 331 struct in6pcb *head = in6p->in6p_head; 332 u_int16_t last_port, lport = 0; 333 int wild = 0; 334 void *t; 335 u_int16_t min, max; 336 struct proc *p = curproc; /* XXX */ 337 338 /* XXX: this is redundant when called from in6_pcbbind */ 339 if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0 && 340 ((so->so_proto->pr_flags & PR_CONNREQUIRED) == 0 || 341 (so->so_options & SO_ACCEPTCONN) == 0)) 342 wild = IN6PLOOKUP_WILDCARD; 343 344 if (in6p->in6p_flags & IN6P_LOWPORT) { 345 if (p == 0 || (suser(p->p_ucred, &p->p_acflag) != 0)) 346 return (EACCES); 347 min = IPV6PORT_RESERVEDMIN; 348 max = IPV6PORT_RESERVEDMAX; 349 } else { 350 min = IPV6PORT_ANONMIN; 351 max = IPV6PORT_ANONMAX; 352 } 353 354 /* value out of range */ 355 if (head->in6p_lport < min) 356 head->in6p_lport = min; 357 else if (head->in6p_lport > max) 358 head->in6p_lport = min; 359 last_port = head->in6p_lport; 360 goto startover; /*to randomize*/ 361 for (;;) { 362 lport = htons(head->in6p_lport); 363 if (IN6_IS_ADDR_V4MAPPED(laddr)) { 364 #if 0 365 t = in_pcblookup_bind(&tcbtable, 366 (struct in_addr *)&in6p->in6p_laddr.s6_addr32[3], 367 lport); 368 #else 369 t = NULL; 370 #endif 371 } else { 372 t = in6_pcblookup(head, &zeroin6_addr, 0, laddr, 373 lport, wild); 374 } 375 if (t == 0) 376 break; 377 startover: 378 if (head->in6p_lport >= max) 379 head->in6p_lport = min; 380 else 381 head->in6p_lport++; 382 if (head->in6p_lport == last_port) 383 return (EADDRINUSE); 384 } 385 386 in6p->in6p_lport = lport; 387 return(0); /* success */ 388 } 389