- /*
- * 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;
- ifafree(&ia6->ia_ifa);
- 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;
- ifafree(&ia6->ia_ifa);
- 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 = ia6->ia_addr.sin6_addr;
- ifafree(&ia6->ia_ifa);
- 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) {
- ifaref(&rt->rt_ifa);
- ia6 = ifatoia6(rt->rt_ifa);
- }
- }
- if (ia6 == 0) {
- *errorp = EADDRNOTAVAIL;
- return(0);
- }
- *src_storage = satosin6(&ia6->ia_addr)->sin6_addr;
- ifaref(&rt->rt_ifa);
- 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) {
- 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) {
- struct sockaddr_in6 *dst6;
-
- /* No route yet, so try to acquire one */
- bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
- dst6 = (struct sockaddr_in6 *)&ro->ro_dst;
- dst6->sin6_family = AF_INET6;
- dst6->sin6_len = sizeof(struct sockaddr_in6);
- dst6->sin6_addr = *dst;
- if (IN6_IS_ADDR_MULTICAST(dst)) {
- ro->ro_rt = rtalloc1(&((struct route *)ro)
- ->ro_dst, 0, 0UL);
- } else {
- 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 ?*/
- ifaref(ro->ro_rt->rt_ifa);
- ia6 = ifatoia6(ro->ro_rt->rt_ifa);
- }
- }
- if (ia6 == 0) {
- *errorp = EHOSTUNREACH; /* no route */
- return(0);
- }
- *src_storage = satosin6(&ia6->ia_addr)->sin6_addr;
- ifaref(&rt->rt_ifa);
- return(src_storage);
- }
-
- *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(
- 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);
projects / apple / xnu.git / blobdiff