/* $FreeBSD: src/sys/netinet6/in6_src.c,v 1.1.2.2 2001/07/03 11:01:52 ume Exp $ */ /* $KAME: in6_src.c,v 1.37 2001/03/29 05:34:31 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 <sys/param.h> #include <sys/systm.h> #include <sys/malloc.h> #include <sys/mbuf.h> #include <sys/protosw.h> #include <sys/socket.h> #include <sys/socketvar.h> #include <sys/errno.h> #include <sys/time.h> #include <sys/proc.h> #include <kern/lock.h> #include <net/if.h> #include <net/route.h> #include <netinet/in.h> #include <netinet/in_var.h> #include <netinet/in_systm.h> #include <netinet/ip.h> #include <netinet/in_pcb.h> #include <netinet6/in6_var.h> #include <netinet/ip6.h> #include <netinet6/in6_pcb.h> #include <netinet6/ip6_var.h> #include <netinet6/nd6.h> #if ENABLE_DEFAULT_SCOPE #include <netinet6/scope6_var.h> #endif #include <net/net_osdep.h> #include "loop.h" extern lck_mtx_t *rt_mtx; /* * Return an IPv6 address, which is the most appropriate for a given * destination and user specified options. * If necessary, this function lookups the routing table and returns * an entry to the caller for later use. */ struct in6_addr * in6_selectsrc( struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, struct ip6_moptions *mopts, struct route_in6 *ro, struct in6_addr *laddr, struct in6_addr *src_storage, 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); } *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; return src_storage; } /* * 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); } *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; return src_storage; } /* * 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); } *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; return src_storage; } } /* * 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, 0); if (rt) { ia6 = in6_ifawithscope(rt->rt_ifp, dst); if (ia6 == 0) ia6 = ifatoia6(rt->rt_ifa); } if (ia6 == 0) { *errorp = EADDRNOTAVAIL; return(0); } *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; return src_storage; } } /* * If route is known or can be allocated now, * our src addr is taken from the i/f, else punt. */ if (ro) { lck_mtx_lock(rt_mtx); if (ro->ro_rt && (!(ro->ro_rt->rt_flags & RTF_UP) || satosin6(&ro->ro_dst)->sin6_family != AF_INET6 || !IN6_ARE_ADDR_EQUAL(&satosin6(&ro->ro_dst)->sin6_addr, dst))) { rtfree_locked(ro->ro_rt); ro->ro_rt = (struct rtentry *)0; } if (ro->ro_rt == (struct rtentry *)0 || ro->ro_rt->rt_ifp == 0) { struct sockaddr_in6 *sa6; /* No route yet, so try to acquire one */ bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); sa6 = (struct sockaddr_in6 *)&ro->ro_dst; sa6->sin6_family = AF_INET6; sa6->sin6_len = sizeof(struct sockaddr_in6); sa6->sin6_addr = *dst; sa6->sin6_scope_id = dstsock->sin6_scope_id; if (IN6_IS_ADDR_MULTICAST(dst)) { ro->ro_rt = rtalloc1_locked(&((struct route *)ro) ->ro_dst, 0, 0UL); } else { rtalloc_ign_locked((struct route *)ro, 0UL); } } lck_mtx_unlock(rt_mtx); /* * 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) { ia6 = ifatoia6(ro->ro_rt->rt_ifa); if (ia6) ifaref(&ia6->ia_ifa); } else { ifaref(&ia6->ia_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); *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; return src_storage; } #endif /* 0 */ if (ia6 == 0) { *errorp = EHOSTUNREACH; /* no route */ return(0); } *src_storage = satosin6(&ia6->ia_addr)->sin6_addr; ifafree(&ia6->ia_ifa); return src_storage; } *errorp = EADDRNOTAVAIL; return(0); } /* * Default hop limit selection. The precedence is as follows: * 1. Hoplimit value 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( struct in6pcb *in6p, struct ifnet *ifp) { if (in6p && in6p->in6p_hops >= 0) return(in6p->in6p_hops); else if (ifp) return(nd_ifinfo[ifp->if_index].chlim); else return(ip6_defhlim); } /* * XXX: this is borrowed from in6_pcbbind(). If possible, we should * share this function by all *bsd*... */ int in6_pcbsetport(laddr, inp, p, locked) struct in6_addr *laddr; struct inpcb *inp; struct proc *p; int locked; { struct socket *so = inp->inp_socket; u_int16_t lport = 0, first, last, *lastport; int count, error = 0, wild = 0; struct inpcbinfo *pcbinfo = inp->inp_pcbinfo; if (!locked) { /* Make sure we don't run into a deadlock: 4052373 */ if (!lck_rw_try_lock_exclusive(pcbinfo->mtx)) { socket_unlock(inp->inp_socket, 0); lck_rw_lock_exclusive(pcbinfo->mtx); socket_lock(inp->inp_socket, 0); } } /* XXX: this is redundant when called from in6_pcbbind */ if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0) wild = INPLOOKUP_WILDCARD; inp->inp_flags |= INP_ANONPORT; if (inp->inp_flags & INP_HIGHPORT) { first = ipport_hifirstauto; /* sysctl */ last = ipport_hilastauto; lastport = &pcbinfo->lasthi; } else if (inp->inp_flags & INP_LOWPORT) { if (p && (error = proc_suser(p))) { if (!locked) lck_rw_done(pcbinfo->mtx); return error; } first = ipport_lowfirstauto; /* 1023 */ last = ipport_lowlastauto; /* 600 */ lastport = &pcbinfo->lastlow; } else { first = ipport_firstauto; /* sysctl */ last = ipport_lastauto; lastport = &pcbinfo->lastport; } /* * Simple check to ensure all ports are not used up causing * a deadlock here. * * We split the two cases (up and down) so that the direction * is not being tested on each round of the loop. */ if (first > last) { /* * counting down */ count = first - last; do { if (count-- < 0) { /* completely used? */ /* * Undo any address bind that may have * occurred above. */ inp->in6p_laddr = in6addr_any; if (!locked) lck_rw_done(pcbinfo->mtx); return (EAGAIN); } --*lastport; if (*lastport > first || *lastport < last) *lastport = first; lport = htons(*lastport); } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, lport, wild)); } else { /* * counting up */ count = last - first; do { if (count-- < 0) { /* completely used? */ /* * Undo any address bind that may have * occurred above. */ inp->in6p_laddr = in6addr_any; if (!locked) lck_rw_done(pcbinfo->mtx); return (EAGAIN); } ++*lastport; if (*lastport < first || *lastport > last) *lastport = first; lport = htons(*lastport); } while (in6_pcblookup_local(pcbinfo, &inp->in6p_laddr, lport, wild)); } inp->inp_lport = lport; if (in_pcbinshash(inp, 1) != 0) { inp->in6p_laddr = in6addr_any; inp->inp_lport = 0; if (!locked) lck_rw_done(pcbinfo->mtx); return (EAGAIN); } if (!locked) lck_rw_done(pcbinfo->mtx); return(0); } /* * generate kernel-internal form (scopeid embedded into s6_addr16[1]). * If the address scope of is link-local, embed the interface index in the * address. The routine determines our precedence * between advanced API scope/interface specification and basic API * specification. * * this function should be nuked in the future, when we get rid of * embedded scopeid thing. * * XXX actually, it is over-specification to return ifp against sin6_scope_id. * there can be multiple interfaces that belong to a particular scope zone * (in specification, we have 1:N mapping between a scope zone and interfaces). * we may want to change the function to return something other than ifp. */ int in6_embedscope( struct in6_addr *in6, const struct sockaddr_in6 *sin6, #ifdef HAVE_NRL_INPCB struct inpcb *in6p, #define in6p_outputopts inp_outputopts6 #define in6p_moptions inp_moptions6 #else struct in6pcb *in6p, #endif struct ifnet **ifpp) { struct ifnet *ifp = NULL; u_int32_t scopeid; *in6 = sin6->sin6_addr; scopeid = sin6->sin6_scope_id; if (ifpp) *ifpp = NULL; /* * don't try to read sin6->sin6_addr beyond here, since the caller may * ask us to overwrite existing sockaddr_in6 */ #ifdef ENABLE_DEFAULT_SCOPE if (scopeid == 0) scopeid = scope6_addr2default(in6); #endif if (IN6_IS_SCOPE_LINKLOCAL(in6)) { struct in6_pktinfo *pi; /* * KAME assumption: link id == interface id */ if (in6p && in6p->in6p_outputopts && (pi = in6p->in6p_outputopts->ip6po_pktinfo) && pi->ipi6_ifindex) { ifp = ifindex2ifnet[pi->ipi6_ifindex]; in6->s6_addr16[1] = htons(pi->ipi6_ifindex); } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && in6p->in6p_moptions && in6p->in6p_moptions->im6o_multicast_ifp) { ifp = in6p->in6p_moptions->im6o_multicast_ifp; in6->s6_addr16[1] = htons(ifp->if_index); } else if (scopeid) { /* boundary check */ if (scopeid < 0 || if_index < scopeid) return ENXIO; /* XXX EINVAL? */ ifp = ifindex2ifnet[scopeid]; /*XXX assignment to 16bit from 32bit variable */ in6->s6_addr16[1] = htons(scopeid & 0xffff); } if (ifpp) *ifpp = ifp; } return 0; } #if HAVE_NRL_INPCB #undef in6p_outputopts #undef in6p_moptions #endif /* * generate standard sockaddr_in6 from embedded form. * touches sin6_addr and sin6_scope_id only. * * this function should be nuked in the future, when we get rid of * embedded scopeid thing. */ int in6_recoverscope( struct sockaddr_in6 *sin6, const struct in6_addr *in6, struct ifnet *ifp) { u_int32_t scopeid; sin6->sin6_addr = *in6; /* * don't try to read *in6 beyond here, since the caller may * ask us to overwrite existing sockaddr_in6 */ sin6->sin6_scope_id = 0; if (IN6_IS_SCOPE_LINKLOCAL(in6)) { /* * KAME assumption: link id == interface id */ scopeid = ntohs(sin6->sin6_addr.s6_addr16[1]); if (scopeid) { /* sanity check */ if (scopeid < 0 || if_index < scopeid) return ENXIO; if (ifp && ifp->if_index != scopeid) return ENXIO; sin6->sin6_addr.s6_addr16[1] = 0; sin6->sin6_scope_id = scopeid; } } return 0; } /* * just clear the embedded scope identifer. * XXX: currently used for bsdi4 only as a supplement function. */ void in6_clearscope(addr) struct in6_addr *addr; { if (IN6_IS_SCOPE_LINKLOCAL(addr)) addr->s6_addr16[1] = 0; }