in6_src.c revision 1.1
1/* $OpenBSD: in6_src.c,v 1.1 1999/12/08 06:50:21 itojun Exp $ */ 2 3/* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32/* 33 * Copyright (c) 1982, 1986, 1991, 1993 34 * The Regents of the University of California. All rights reserved. 35 * 36 * Redistribution and use in source and binary forms, with or without 37 * modification, are permitted provided that the following conditions 38 * are met: 39 * 1. Redistributions of source code must retain the above copyright 40 * notice, this list of conditions and the following disclaimer. 41 * 2. Redistributions in binary form must reproduce the above copyright 42 * notice, this list of conditions and the following disclaimer in the 43 * documentation and/or other materials provided with the distribution. 44 * 3. All advertising materials mentioning features or use of this software 45 * must display the following acknowledgement: 46 * This product includes software developed by the University of 47 * California, Berkeley and its contributors. 48 * 4. Neither the name of the University nor the names of its contributors 49 * may be used to endorse or promote products derived from this software 50 * without specific prior written permission. 51 * 52 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 53 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 55 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 56 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 62 * SUCH DAMAGE. 63 * 64 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 65 */ 66 67#ifdef __NetBSD__ /*XXX*/ 68#include "opt_ipsec.h" 69#endif 70 71#include <sys/param.h> 72#include <sys/systm.h> 73#include <sys/malloc.h> 74#include <sys/mbuf.h> 75#include <sys/protosw.h> 76#include <sys/socket.h> 77#include <sys/socketvar.h> 78#include <sys/ioctl.h> 79#include <sys/errno.h> 80#include <sys/time.h> 81#include <sys/proc.h> 82 83#include <net/if.h> 84#include <net/route.h> 85 86#include <netinet/in.h> 87#include <netinet/in_var.h> 88#include <netinet/in_systm.h> 89#include <netinet/ip.h> 90#include <netinet/in_pcb.h> 91#include <netinet6/in6_var.h> 92#include <netinet6/ip6.h> 93#if 0 94#include <netinet6/in6_pcb.h> 95#endif 96#include <netinet6/ip6_var.h> 97#include <netinet6/nd6.h> 98 99#ifndef __bsdi__ 100#include "loop.h" 101#endif 102#if defined(__NetBSD__) || defined(__OpenBSD__) 103extern struct ifnet loif[NLOOP]; 104#endif 105 106/* 107 * Return an IPv6 address, which is the most appropriate for given 108 * destination and user specified options. 109 * If necessary, this function lookups the routing table and return 110 * an entry to the caller for later use. 111 */ 112struct in6_addr * 113in6_selectsrc(dstsock, opts, mopts, ro, laddr, errorp) 114 struct sockaddr_in6 *dstsock; 115 struct ip6_pktopts *opts; 116 struct ip6_moptions *mopts; 117 struct route_in6 *ro; 118 struct in6_addr *laddr; 119 int *errorp; 120{ 121 struct in6_addr *dst; 122 struct in6_ifaddr *ia6 = 0; 123 struct in6_pktinfo *pi = NULL; 124 125 dst = &dstsock->sin6_addr; 126 *errorp = 0; 127 128 /* 129 * If the source address is explicitly specified by the caller, 130 * use it. 131 */ 132 if (opts && (pi = opts->ip6po_pktinfo) && 133 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) 134 return(&pi->ipi6_addr); 135 136 /* 137 * If the source address is not specified but the socket(if any) 138 * is already bound, use the bound address. 139 */ 140 if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) 141 return(laddr); 142 143 /* 144 * If the caller doesn't specify the source address but 145 * the outgoing interface, use an address associated with 146 * the interface. 147 */ 148 if (pi && pi->ipi6_ifindex) { 149 /* XXX boundary check is assumed to be already done. */ 150 ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex], 151 dst); 152 if (ia6 == 0) { 153 *errorp = EADDRNOTAVAIL; 154 return(0); 155 } 156 return(&satosin6(&ia6->ia_addr)->sin6_addr); 157 } 158 159 /* 160 * If the destination address is a link-local unicast address or 161 * a multicast address, and if the outgoing interface is specified 162 * by the sin6_scope_id filed, use an address associated with the 163 * interface. 164 * XXX: We're now trying to define more specific semantics of 165 * sin6_scope_id field, so this part will be rewritten in 166 * the near future. 167 */ 168 if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) && 169 dstsock->sin6_scope_id) { 170 /* 171 * I'm not sure if boundary check for scope_id is done 172 * somewhere... 173 */ 174 if (dstsock->sin6_scope_id < 0 || 175 if_index < dstsock->sin6_scope_id) { 176 *errorp = ENXIO; /* XXX: better error? */ 177 return(0); 178 } 179 ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id], 180 dst); 181 if (ia6 == 0) { 182 *errorp = EADDRNOTAVAIL; 183 return(0); 184 } 185 return(&satosin6(&ia6->ia_addr)->sin6_addr); 186 } 187 188 /* 189 * If the destination address is a multicast address and 190 * the outgoing interface for the address is specified 191 * by the caller, use an address associated with the interface. 192 * There is a sanity check here; if the destination has node-local 193 * scope, the outgoing interfacde should be a loopback address. 194 * Even if the outgoing interface is not specified, we also 195 * choose a loopback interface as the outgoing interface. 196 */ 197 if (IN6_IS_ADDR_MULTICAST(dst)) { 198 struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL; 199#ifdef __bsdi__ 200#if _BSDI_VERSION >= 199802 201 extern struct ifnet *loifp; 202#else 203 extern struct ifnet loif; 204 struct ifnet *loifp = &loif; 205#endif 206#endif 207 208 if (ifp == NULL && IN6_IS_ADDR_MC_NODELOCAL(dst)) { 209#ifdef __bsdi__ 210 ifp = loifp; 211#else 212 ifp = &loif[0]; 213#endif 214 } 215 216 if (ifp) { 217 ia6 = in6_ifawithscope(ifp, dst); 218 if (ia6 == 0) { 219 *errorp = EADDRNOTAVAIL; 220 return(0); 221 } 222 return(&satosin6(&ia6->ia_addr)->sin6_addr); 223 } 224 } 225 226 /* 227 * If the next hop address for the packet is specified 228 * by caller, use an address associated with the route 229 * to the next hop. 230 */ 231 { 232 struct sockaddr_in6 *sin6_next; 233 struct rtentry *rt; 234 235 if (opts && opts->ip6po_nexthop) { 236 sin6_next = satosin6(opts->ip6po_nexthop); 237 rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); 238 if (rt) { 239 ia6 = in6_ifawithscope(rt->rt_ifp, dst); 240 if (ia6 == 0) 241 ia6 = ifatoia6(rt->rt_ifa); 242 } 243 if (ia6 == 0) { 244 *errorp = EADDRNOTAVAIL; 245 return(0); 246 } 247 return(&satosin6(&ia6->ia_addr)->sin6_addr); 248 } 249 } 250 251 /* 252 * If route is known or can be allocated now, 253 * our src addr is taken from the i/f, else punt. 254 */ 255 if (ro) { 256 if (ro->ro_rt && 257 !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst)) { 258 RTFREE(ro->ro_rt); 259 ro->ro_rt = (struct rtentry *)0; 260 } 261 if (ro->ro_rt == (struct rtentry *)0 || 262 ro->ro_rt->rt_ifp == (struct ifnet *)0) { 263 /* No route yet, so try to acquire one */ 264 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 265 ro->ro_dst.sin6_family = AF_INET6; 266 ro->ro_dst.sin6_len = sizeof(struct sockaddr_in6); 267 ro->ro_dst.sin6_addr = *dst; 268 if (IN6_IS_ADDR_MULTICAST(dst)) { 269#ifdef __FreeBSD__ 270 ro->ro_rt = rtalloc1(&((struct route *)ro) 271 ->ro_dst, 0, 0UL); 272#endif /*__FreeBSD__*/ 273#if defined(__bsdi__) || defined(__NetBSD__) 274 ro->ro_rt = rtalloc1(&((struct route *)ro) 275 ->ro_dst, 0); 276#endif /*__bsdi__*/ 277 } else { 278#ifdef __FreeBSD__ 279 rtcalloc((struct route *)ro); 280#else 281 rtalloc((struct route *)ro); 282#endif 283 } 284 } 285 286 /* 287 * in_pcbconnect() checks out IFF_LOOPBACK to skip using 288 * the address. But we don't know why it does so. 289 * It is necessary to ensure the scope even for lo0 290 * so doesn't check out IFF_LOOPBACK. 291 */ 292 293 if (ro->ro_rt) { 294 ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst); 295 if (ia6 == 0) /* xxx scope error ?*/ 296 ia6 = ifatoia6(ro->ro_rt->rt_ifa); 297 } 298#if 0 299 /* 300 * xxx The followings are necessary? (kazu) 301 * I don't think so. 302 * It's for SO_DONTROUTE option in IPv4.(jinmei) 303 */ 304 if (ia6 == 0) { 305 struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; 306 307 sin6->sin6_addr = *dst; 308 309 ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); 310 if (ia6 == 0) 311 ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); 312 if (ia6 == 0) 313 return(0); 314 return(&satosin6(&ia6->ia_addr)->sin6_addr); 315 } 316#endif /* 0 */ 317 if (ia6 == 0) { 318 *errorp = EHOSTUNREACH; /* no route */ 319 return(0); 320 } 321 return(&satosin6(&ia6->ia_addr)->sin6_addr); 322 } 323 324 *errorp = EADDRNOTAVAIL; 325 return(0); 326} 327 328/* 329 * Default hop limit selection. The precedence is as follows: 330 * 1. Hoplimit valued specified via ioctl. 331 * 2. (If the outgoing interface is detected) the current 332 * hop limit of the interface specified by router advertisement. 333 * 3. The system default hoplimit. 334*/ 335int 336in6_selecthlim(inp, ifp) 337 struct inpcb *inp; 338 struct ifnet *ifp; 339{ 340 if (inp && inp->inp_hops >= 0) 341 return(inp->inp_hops); 342 else if (ifp) 343 return(nd_ifinfo[ifp->if_index].chlim); 344 else 345 return(ip6_defhlim); 346} 347