/* $OpenBSD: in6_src.c,v 1.4 2000/02/28 11:55:22 itojun Exp $ */ /* * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Copyright (c) 1982, 1986, 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "loop.h" extern struct ifnet loif[NLOOP]; /* * Return an IPv6 address, which is the most appropriate for given * destination and user specified options. * If necessary, this function lookups the routing table and return * an entry to the caller for later use. */ struct in6_addr * in6_selectsrc(dstsock, opts, mopts, ro, laddr, errorp) struct sockaddr_in6 *dstsock; struct ip6_pktopts *opts; struct ip6_moptions *mopts; struct route_in6 *ro; struct in6_addr *laddr; int *errorp; { struct in6_addr *dst; struct in6_ifaddr *ia6 = 0; struct in6_pktinfo *pi = NULL; dst = &dstsock->sin6_addr; *errorp = 0; /* * If the source address is explicitly specified by the caller, * use it. */ if (opts && (pi = opts->ip6po_pktinfo) && !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) return(&pi->ipi6_addr); /* * If the source address is not specified but the socket(if any) * is already bound, use the bound address. */ if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) return(laddr); /* * If the caller doesn't specify the source address but * the outgoing interface, use an address associated with * the interface. */ if (pi && pi->ipi6_ifindex) { /* XXX boundary check is assumed to be already done. */ ia6 = in6_ifawithscope(ifindex2ifnet[pi->ipi6_ifindex], dst); if (ia6 == 0) { *errorp = EADDRNOTAVAIL; return(0); } return(&satosin6(&ia6->ia_addr)->sin6_addr); } /* * If the destination address is a link-local unicast address or * a multicast address, and if the outgoing interface is specified * by the sin6_scope_id filed, use an address associated with the * interface. * XXX: We're now trying to define more specific semantics of * sin6_scope_id field, so this part will be rewritten in * the near future. */ if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MULTICAST(dst)) && dstsock->sin6_scope_id) { /* * I'm not sure if boundary check for scope_id is done * somewhere... */ if (dstsock->sin6_scope_id < 0 || if_index < dstsock->sin6_scope_id) { *errorp = ENXIO; /* XXX: better error? */ return(0); } ia6 = in6_ifawithscope(ifindex2ifnet[dstsock->sin6_scope_id], dst); if (ia6 == 0) { *errorp = EADDRNOTAVAIL; return(0); } return(&satosin6(&ia6->ia_addr)->sin6_addr); } /* * If the destination address is a multicast address and * the outgoing interface for the address is specified * by the caller, use an address associated with the interface. * There is a sanity check here; if the destination has node-local * scope, the outgoing interfacde should be a loopback address. * Even if the outgoing interface is not specified, we also * choose a loopback interface as the outgoing interface. */ if (IN6_IS_ADDR_MULTICAST(dst)) { struct ifnet *ifp = mopts ? mopts->im6o_multicast_ifp : NULL; if (ifp == NULL && IN6_IS_ADDR_MC_NODELOCAL(dst)) { ifp = &loif[0]; } if (ifp) { ia6 = in6_ifawithscope(ifp, dst); if (ia6 == 0) { *errorp = EADDRNOTAVAIL; return(0); } return(&satosin6(&ia6->ia_addr)->sin6_addr); } } /* * If the next hop address for the packet is specified * by caller, use an address associated with the route * to the next hop. */ { struct sockaddr_in6 *sin6_next; struct rtentry *rt; if (opts && opts->ip6po_nexthop) { sin6_next = satosin6(opts->ip6po_nexthop); rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); if (rt) { ia6 = in6_ifawithscope(rt->rt_ifp, dst); if (ia6 == 0) ia6 = ifatoia6(rt->rt_ifa); } if (ia6 == 0) { *errorp = EADDRNOTAVAIL; return(0); } return(&satosin6(&ia6->ia_addr)->sin6_addr); } } /* * If route is known or can be allocated now, * our src addr is taken from the i/f, else punt. */ if (ro) { if (ro->ro_rt && !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst)) { RTFREE(ro->ro_rt); ro->ro_rt = (struct rtentry *)0; } if (ro->ro_rt == (struct rtentry *)0 || ro->ro_rt->rt_ifp == (struct ifnet *)0) { /* No route yet, so try to acquire one */ bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); ro->ro_dst.sin6_family = AF_INET6; ro->ro_dst.sin6_len = sizeof(struct sockaddr_in6); ro->ro_dst.sin6_addr = *dst; if (!IN6_IS_ADDR_MULTICAST(dst)) { rtalloc((struct route *)ro); } } /* * in_pcbconnect() checks out IFF_LOOPBACK to skip using * the address. But we don't know why it does so. * It is necessary to ensure the scope even for lo0 * so doesn't check out IFF_LOOPBACK. */ if (ro->ro_rt) { ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst); if (ia6 == 0) /* xxx scope error ?*/ ia6 = ifatoia6(ro->ro_rt->rt_ifa); } #if 0 /* * xxx The followings are necessary? (kazu) * I don't think so. * It's for SO_DONTROUTE option in IPv4.(jinmei) */ if (ia6 == 0) { struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; sin6->sin6_addr = *dst; ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); if (ia6 == 0) ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); if (ia6 == 0) return(0); return(&satosin6(&ia6->ia_addr)->sin6_addr); } #endif /* 0 */ if (ia6 == 0) { *errorp = EHOSTUNREACH; /* no route */ return(0); } return(&satosin6(&ia6->ia_addr)->sin6_addr); } *errorp = EADDRNOTAVAIL; return(0); } /* * Default hop limit selection. The precedence is as follows: * 1. Hoplimit valued specified via ioctl. * 2. (If the outgoing interface is detected) the current * hop limit of the interface specified by router advertisement. * 3. The system default hoplimit. */ int in6_selecthlim(inp, ifp) struct inpcb *inp; struct ifnet *ifp; { if (inp && inp->inp_hops >= 0) return(inp->inp_hops); else if (ifp) return(nd_ifinfo[ifp->if_index].chlim); else return(ip6_defhlim); }