Including errno.h and still declaring errno is BROKEN.

[dragonfly/netmp.git] / sys / netinet6 / in6_pcb.c

/*      $FreeBSD: src/sys/netinet6/in6_pcb.c,v 1.10.2.9 2003/01/24 05:11:35 sam Exp $   */
/*      $DragonFly: src/sys/netinet6/in6_pcb.c,v 1.26 2005/03/06 05:09:25 hsu Exp $     */
/*      $KAME: in6_pcb.c,v 1.31 2001/05/21 05:45:10 jinmei 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 "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sockio.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/proc.h>
#include <sys/jail.h>

#include <vm/vm_zone.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/route.h>

#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip6.h>
#include <netinet/ip_var.h>
#include <netinet6/ip6_var.h>
#include <netinet6/nd6.h>
#include <netinet/in_pcb.h>
#include <netinet6/in6_pcb.h>

#ifdef IPSEC
#include <netinet6/ipsec.h>
#ifdef INET6
#include <netinet6/ipsec6.h>
#endif
#include <netinet6/ah.h>
#ifdef INET6
#include <netinet6/ah6.h>
#endif
#include <netproto/key/key.h>
#endif /* IPSEC */

#ifdef FAST_IPSEC
#include <netproto/ipsec/ipsec.h>
#include <netproto/ipsec/ipsec6.h>
#include <netproto/ipsec/key.h>
#define IPSEC
#endif /* FAST_IPSEC */

struct  in6_addr zeroin6_addr;

int
in6_pcbbind(struct inpcb *inp, struct sockaddr *nam, struct thread *td)
{
        struct socket *so = inp->inp_socket;
        struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)NULL;
        struct inpcbinfo *pcbinfo = inp->inp_pcbinfo;
        u_short lport = 0;
        int wild = 0, reuseport = (so->so_options & SO_REUSEPORT);

        if (!in6_ifaddr) /* XXX broken! */
                return (EADDRNOTAVAIL);
        if (inp->inp_lport || !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
                return(EINVAL);
        if ((so->so_options & (SO_REUSEADDR|SO_REUSEPORT)) == 0)
                wild = 1;
        if (nam) {
                sin6 = (struct sockaddr_in6 *)nam;
                if (nam->sa_len != sizeof(*sin6))
                        return(EINVAL);
                /*
                 * family check.
                 */
                if (nam->sa_family != AF_INET6)
                        return(EAFNOSUPPORT);

                /* KAME hack: embed scopeid */
                if (in6_embedscope(&sin6->sin6_addr, sin6, inp, NULL) != 0)
                        return EINVAL;
                /* this must be cleared for ifa_ifwithaddr() */
                sin6->sin6_scope_id = 0;

                lport = sin6->sin6_port;
                if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
                        /*
                         * Treat SO_REUSEADDR as SO_REUSEPORT for multicast;
                         * allow compepte duplication of binding if
                         * SO_REUSEPORT is set, or if SO_REUSEADDR is set
                         * and a multicast address is bound on both
                         * new and duplicated sockets.
                         */
                        if (so->so_options & SO_REUSEADDR)
                                reuseport = SO_REUSEADDR|SO_REUSEPORT;
                } else if (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
                        struct ifaddr *ia = NULL;

                        sin6->sin6_port = 0;            /* yech... */
                        if ((ia = ifa_ifwithaddr((struct sockaddr *)sin6)) == 0)
                                return(EADDRNOTAVAIL);

                        /*
                         * XXX: bind to an anycast address might accidentally
                         * cause sending a packet with anycast source address.
                         * We should allow to bind to a deprecated address, since
                         * the application dare to use it.
                         */
                        if (ia &&
                            ((struct in6_ifaddr *)ia)->ia6_flags &
                            (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY|IN6_IFF_DETACHED)) {
                                return(EADDRNOTAVAIL);
                        }
                }
                if (lport) {
                        struct inpcb *t;
                        struct proc *p = td->td_proc; /* may be NULL */

                        /* GROSS */
                        if (ntohs(lport) < IPV6PORT_RESERVED && p &&
                            suser_cred(p->p_ucred, PRISON_ROOT))
                                return(EACCES);
                        if (so->so_cred->cr_uid != 0 &&
                            !IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
                                t = in6_pcblookup_local(pcbinfo,
                                    &sin6->sin6_addr, lport,
                                    INPLOOKUP_WILDCARD);
                                if (t &&
                                    (!IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) ||
                                     !IN6_IS_ADDR_UNSPECIFIED(&t->in6p_laddr) ||
                                     (t->inp_socket->so_options &
                                      SO_REUSEPORT) == 0) &&
                                    (so->so_cred->cr_uid !=
                                     t->inp_socket->so_cred->cr_uid))
                                        return (EADDRINUSE);
                                if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
                                    IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
                                        struct sockaddr_in sin;

                                        in6_sin6_2_sin(&sin, sin6);
                                        t = in_pcblookup_local(pcbinfo,
                                                sin.sin_addr, lport,
                                                INPLOOKUP_WILDCARD);
                                        if (t &&
                                            (so->so_cred->cr_uid !=
                                             t->inp_socket->so_cred->cr_uid) &&
                                            (ntohl(t->inp_laddr.s_addr) !=
                                             INADDR_ANY ||
                                             INP_SOCKAF(so) ==
                                             INP_SOCKAF(t->inp_socket)))
                                                return (EADDRINUSE);
                                }
                        }
                        t = in6_pcblookup_local(pcbinfo, &sin6->sin6_addr,
                                                lport, wild);
                        if (t && (reuseport & t->inp_socket->so_options) == 0)
                                return(EADDRINUSE);
                        if ((inp->inp_flags & IN6P_IPV6_V6ONLY) == 0 &&
                            IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr)) {
                                struct sockaddr_in sin;

                                in6_sin6_2_sin(&sin, sin6);
                                t = in_pcblookup_local(pcbinfo, sin.sin_addr,
                                                       lport, wild);
                                if (t &&
                                    (reuseport & t->inp_socket->so_options)
                                    == 0 &&
                                    (ntohl(t->inp_laddr.s_addr)
                                     != INADDR_ANY ||
                                     INP_SOCKAF(so) ==
                                     INP_SOCKAF(t->inp_socket)))
                                        return (EADDRINUSE);
                        }
                }
                inp->in6p_laddr = sin6->sin6_addr;
        }
        if (lport == 0) {
                int e;
                if ((e = in6_pcbsetport(&inp->in6p_laddr, inp, td)) != 0)
                        return(e);
        }
        else {
                inp->inp_lport = lport;
                if (in_pcbinsporthash(inp) != 0) {
                        inp->in6p_laddr = in6addr_any;
                        inp->inp_lport = 0;
                        return (EAGAIN);
                }
        }
        return(0);
}

/*
 *   Transform old in6_pcbconnect() into an inner subroutine for new
 *   in6_pcbconnect(): Do some validity-checking on the remote
 *   address (in mbuf 'nam') and then determine local host address
 *   (i.e., which interface) to use to access that remote host.
 *
 *   This preserves definition of in6_pcbconnect(), while supporting a
 *   slightly different version for T/TCP.  (This is more than
 *   a bit of a kludge, but cleaning up the internal interfaces would
 *   have forced minor changes in every protocol).
 */

int
in6_pcbladdr(struct inpcb *inp, struct sockaddr *nam,
             struct in6_addr **plocal_addr6)
{
        struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
        struct ifnet *ifp = NULL;
        int error = 0;

        if (nam->sa_len != sizeof (*sin6))
                return (EINVAL);
        if (sin6->sin6_family != AF_INET6)
                return (EAFNOSUPPORT);
        if (sin6->sin6_port == 0)
                return (EADDRNOTAVAIL);

        /* KAME hack: embed scopeid */
        if (in6_embedscope(&sin6->sin6_addr, sin6, inp, &ifp) != 0)
                return EINVAL;

        if (in6_ifaddr) {
                /*
                 * If the destination address is UNSPECIFIED addr,
                 * use the loopback addr, e.g ::1.
                 */
                if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
                        sin6->sin6_addr = in6addr_loopback;
        }
        {
                /*
                 * XXX: in6_selectsrc might replace the bound local address
                 * with the address specified by setsockopt(IPV6_PKTINFO).
                 * Is it the intended behavior?
                 */
                *plocal_addr6 = in6_selectsrc(sin6, inp->in6p_outputopts,
                                              inp->in6p_moptions,
                                              &inp->in6p_route,
                                              &inp->in6p_laddr, &error);
                if (*plocal_addr6 == 0) {
                        if (error == 0)
                                error = EADDRNOTAVAIL;
                        return(error);
                }
                /*
                 * Don't do pcblookup call here; return interface in
                 * plocal_addr6
                 * and exit to caller, that will do the lookup.
                 */
        }

        if (inp->in6p_route.ro_rt)
                ifp = inp->in6p_route.ro_rt->rt_ifp;

        return(0);
}

/*
 * Outer subroutine:
 * Connect from a socket to a specified address.
 * Both address and port must be specified in argument sin.
 * If don't have a local address for this socket yet,
 * then pick one.
 */
int
in6_pcbconnect(struct inpcb *inp, struct sockaddr *nam, struct thread *td)
{
        struct in6_addr *addr6;
        struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
        int error;

        /*
         * Call inner routine, to assign local interface address.
         * in6_pcbladdr() may automatically fill in sin6_scope_id.
         */
        if ((error = in6_pcbladdr(inp, nam, &addr6)) != 0)
                return(error);

        if (in6_pcblookup_hash(inp->inp_cpcbinfo, &sin6->sin6_addr,
                               sin6->sin6_port,
                              IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)
                              ? addr6 : &inp->in6p_laddr,
                              inp->inp_lport, 0, NULL) != NULL) {
                return (EADDRINUSE);
        }
        if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
                if (inp->inp_lport == 0) {
                        error = in6_pcbbind(inp, (struct sockaddr *)0, td);
                        if (error)
                                return (error);
                }
                inp->in6p_laddr = *addr6;
        }
        inp->in6p_faddr = sin6->sin6_addr;
        inp->inp_fport = sin6->sin6_port;
        /* update flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
        inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
        if (inp->in6p_flags & IN6P_AUTOFLOWLABEL)
                inp->in6p_flowinfo |=
                    (htonl(ip6_flow_seq++) & IPV6_FLOWLABEL_MASK);

        in_pcbinsconnhash(inp);
        return (0);
}

#if 0
/*
 * 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(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(&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 = NULL;
                }
                if (ro->ro_rt == NULL || ro->ro_rt->rt_ifp == NULL) {
                        struct sockaddr_in6 *dst6;

                        /* No route yet, so try to acquire one */
                        bzero(&ro->ro_dst, sizeof(struct sockaddr_in6));
                        dst6 = &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 =
                                  rtpurelookup((struct sockaddr *)&ro->ro_dst);
                        } 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 ?*/
                                ia6 = ifatoia6(ro->ro_rt->rt_ifa);
                }
                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(struct in6pcb *in6p, struct ifnet *ifp)
{
        if (in6p && in6p->in6p_hops >= 0)
                return(in6p->in6p_hops);
        else if (ifp)
                return(ND_IFINFO(ifp)->chlim);
        else
                return(ip6_defhlim);
}
#endif

void
in6_pcbdisconnect(struct inpcb *inp)
{
        bzero((caddr_t)&inp->in6p_faddr, sizeof(inp->in6p_faddr));
        inp->inp_fport = 0;
        /* clear flowinfo - draft-itojun-ipv6-flowlabel-api-00 */
        inp->in6p_flowinfo &= ~IPV6_FLOWLABEL_MASK;
        in_pcbremconnhash(inp);
        if (inp->inp_socket->so_state & SS_NOFDREF)
                in6_pcbdetach(inp);
}

void
in6_pcbdetach(struct inpcb *inp)
{
        struct socket *so = inp->inp_socket;
        struct inpcbinfo *ipi = inp->inp_pcbinfo;

#ifdef IPSEC
        if (inp->in6p_sp != NULL)
                ipsec6_delete_pcbpolicy(inp);
#endif /* IPSEC */
        inp->inp_gencnt = ++ipi->ipi_gencnt;
        in_pcbremlists(inp);
        so->so_pcb = NULL;
        sofree(so);

        if (inp->in6p_options)
                m_freem(inp->in6p_options);
        ip6_freepcbopts(inp->in6p_outputopts);
        ip6_freemoptions(inp->in6p_moptions);
        if (inp->in6p_route.ro_rt)
                rtfree(inp->in6p_route.ro_rt);
        /* Check and free IPv4 related resources in case of mapped addr */
        if (inp->inp_options)
                m_free(inp->inp_options);
        ip_freemoptions(inp->inp_moptions);

        inp->inp_vflag = 0;
        zfree(ipi->ipi_zone, inp);
}

/*
 * The calling convention of in6_setsockaddr() and in6_setpeeraddr() was
 * modified to match the pru_sockaddr() and pru_peeraddr() entry points
 * in struct pr_usrreqs, so that protocols can just reference then directly
 * without the need for a wrapper function.  The socket must have a valid
 * (i.e., non-nil) PCB, but it should be impossible to get an invalid one
 * except through a kernel programming error, so it is acceptable to panic
 * (or in this case trap) if the PCB is invalid.  (Actually, we don't trap
 * because there actually /is/ a programming error somewhere... XXX)
 */
int
in6_setsockaddr(struct socket *so, struct sockaddr **nam)
{
        int s;
        struct inpcb *inp;
        struct sockaddr_in6 *sin6;

        /*
         * Do the malloc first in case it blocks.
         */
        MALLOC(sin6, struct sockaddr_in6 *, sizeof *sin6, M_SONAME, M_WAITOK);
        bzero(sin6, sizeof *sin6);
        sin6->sin6_family = AF_INET6;
        sin6->sin6_len = sizeof(*sin6);

        s = splnet();
        inp = so->so_pcb;
        if (!inp) {
                splx(s);
                free(sin6, M_SONAME);
                return EINVAL;
        }
        sin6->sin6_port = inp->inp_lport;
        sin6->sin6_addr = inp->in6p_laddr;
        splx(s);
        if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
                sin6->sin6_scope_id = ntohs(sin6->sin6_addr.s6_addr16[1]);
        else
                sin6->sin6_scope_id = 0;        /*XXX*/
        if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
                sin6->sin6_addr.s6_addr16[1] = 0;

        *nam = (struct sockaddr *)sin6;
        return 0;
}

int
in6_setpeeraddr(struct socket *so, struct sockaddr **nam)
{
        int s;
        struct inpcb *inp;
        struct sockaddr_in6 *sin6;

        /*
         * Do the malloc first in case it blocks.
         */
        MALLOC(sin6, struct sockaddr_in6 *, sizeof(*sin6), M_SONAME, M_WAITOK);
        bzero((caddr_t)sin6, sizeof (*sin6));
        sin6->sin6_family = AF_INET6;
        sin6->sin6_len = sizeof(struct sockaddr_in6);

        s = splnet();
        inp = so->so_pcb;
        if (!inp) {
                splx(s);
                free(sin6, M_SONAME);
                return EINVAL;
        }
        sin6->sin6_port = inp->inp_fport;
        sin6->sin6_addr = inp->in6p_faddr;
        splx(s);
        if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
                sin6->sin6_scope_id = ntohs(sin6->sin6_addr.s6_addr16[1]);
        else
                sin6->sin6_scope_id = 0;        /*XXX*/
        if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
                sin6->sin6_addr.s6_addr16[1] = 0;

        *nam = (struct sockaddr *)sin6;
        return 0;
}

int
in6_mapped_sockaddr(struct socket *so, struct sockaddr **nam)
{
        struct  inpcb *inp = so->so_pcb;
        int     error;

        if (inp == NULL)
                return EINVAL;
        if (inp->inp_vflag & INP_IPV4) {
                error = in_setsockaddr(so, nam);
                if (error == 0)
                        in6_sin_2_v4mapsin6_in_sock(nam);
        } else
        /* scope issues will be handled in in6_setsockaddr(). */
        error = in6_setsockaddr(so, nam);

        return error;
}

int
in6_mapped_peeraddr(struct socket *so, struct sockaddr **nam)
{
        struct  inpcb *inp = so->so_pcb;
        int     error;

        if (inp == NULL)
                return EINVAL;
        if (inp->inp_vflag & INP_IPV4) {
                error = in_setpeeraddr(so, nam);
                if (error == 0)
                        in6_sin_2_v4mapsin6_in_sock(nam);
        } else
        /* scope issues will be handled in in6_setpeeraddr(). */
        error = in6_setpeeraddr(so, nam);

        return error;
}

/*
 * Pass some notification to all connections of a protocol
 * associated with address dst.  The local address and/or port numbers
 * may be specified to limit the search.  The "usual action" will be
 * taken, depending on the ctlinput cmd.  The caller must filter any
 * cmds that are uninteresting (e.g., no error in the map).
 * Call the protocol specific routine (if any) to report
 * any errors for each matching socket.
 *
 * Must be called at splnet.
 */
void
in6_pcbnotify(struct inpcbhead *head, struct sockaddr *dst, in_port_t fport,
              const struct sockaddr *src, in_port_t lport, int cmd, int arg,
              void (*notify) (struct inpcb *, int))
{
        struct inpcb *inp, *ninp;
        struct sockaddr_in6 sa6_src, *sa6_dst;
        u_int32_t flowinfo;
        int s;

        if ((unsigned)cmd >= PRC_NCMDS || dst->sa_family != AF_INET6)
                return;

        sa6_dst = (struct sockaddr_in6 *)dst;
        if (IN6_IS_ADDR_UNSPECIFIED(&sa6_dst->sin6_addr))
                return;

        /*
         * note that src can be NULL when we get notify by local fragmentation.
         */
        sa6_src = (src == NULL) ? sa6_any : *(const struct sockaddr_in6 *)src;
        flowinfo = sa6_src.sin6_flowinfo;

        /*
         * Redirects go to all references to the destination,
         * and use in6_rtchange to invalidate the route cache.
         * Dead host indications: also use in6_rtchange to invalidate
         * the cache, and deliver the error to all the sockets.
         * Otherwise, if we have knowledge of the local port and address,
         * deliver only to that socket.
         */
        if (PRC_IS_REDIRECT(cmd) || cmd == PRC_HOSTDEAD) {
                fport = 0;
                lport = 0;
                bzero((caddr_t)&sa6_src.sin6_addr, sizeof(sa6_src.sin6_addr));

                if (cmd != PRC_HOSTDEAD)
                        notify = in6_rtchange;
        }
        if (cmd != PRC_MSGSIZE)
                arg = inet6ctlerrmap[cmd];
        s = splnet();
        for (inp = LIST_FIRST(head); inp != NULL; inp = ninp) {
                ninp = LIST_NEXT(inp, inp_list);

                if (inp->inp_flags & INP_PLACEMARKER)
                        continue;

                if ((inp->inp_vflag & INP_IPV6) == 0)
                        continue;

                /*
                 * Detect if we should notify the error. If no source and
                 * destination ports are specifed, but non-zero flowinfo and
                 * local address match, notify the error. This is the case
                 * when the error is delivered with an encrypted buffer
                 * by ESP. Otherwise, just compare addresses and ports
                 * as usual.
                 */
                if (lport == 0 && fport == 0 && flowinfo &&
                    inp->inp_socket != NULL &&
                    flowinfo == (inp->in6p_flowinfo & IPV6_FLOWLABEL_MASK) &&
                    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, &sa6_src.sin6_addr))
                        goto do_notify;
                else if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr,
                                             &sa6_dst->sin6_addr) ||
                         inp->inp_socket == 0 ||
                         (lport && inp->inp_lport != lport) ||
                         (!IN6_IS_ADDR_UNSPECIFIED(&sa6_src.sin6_addr) &&
                          !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
                                              &sa6_src.sin6_addr)) ||
                         (fport && inp->inp_fport != fport))
                        continue;

do_notify:
                if (notify)
                        (*notify)(inp, arg);
        }
        splx(s);
}

/*
 * Lookup a PCB based on the local address and port.
 */
struct inpcb *
in6_pcblookup_local(struct inpcbinfo *pcbinfo, struct in6_addr *laddr,
                    u_int lport_arg, int wild_okay)
{
        struct inpcb *inp;
        int matchwild = 3, wildcard;
        u_short lport = lport_arg;
        struct inpcbporthead *porthash;
        struct inpcbport *phd;
        struct inpcb *match = NULL;

        /*
         * Best fit PCB lookup.
         *
         * First see if this local port is in use by looking on the
         * port hash list.
         */
        porthash = &pcbinfo->porthashbase[INP_PCBPORTHASH(lport,
            pcbinfo->porthashmask)];
        LIST_FOREACH(phd, porthash, phd_hash) {
                if (phd->phd_port == lport)
                        break;
        }
        if (phd != NULL) {
                /*
                 * Port is in use by one or more PCBs. Look for best
                 * fit.
                 */
                LIST_FOREACH(inp, &phd->phd_pcblist, inp_portlist) {
                        wildcard = 0;
                        if ((inp->inp_vflag & INP_IPV6) == 0)
                                continue;
                        if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr))
                                wildcard++;
                        if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) {
                                if (IN6_IS_ADDR_UNSPECIFIED(laddr))
                                        wildcard++;
                                else if (!IN6_ARE_ADDR_EQUAL(
                                        &inp->in6p_laddr, laddr))
                                        continue;
                        } else {
                                if (!IN6_IS_ADDR_UNSPECIFIED(laddr))
                                        wildcard++;
                        }
                        if (wildcard && !wild_okay)
                                continue;
                        if (wildcard < matchwild) {
                                match = inp;
                                if (wildcard == 0)
                                        break;
                                else
                                        matchwild = wildcard;
                        }
                }
        }
        return (match);
}

void
in6_pcbpurgeif0(struct in6pcb *head, struct ifnet *ifp)
{
        struct in6pcb *in6p;
        struct ip6_moptions *im6o;
        struct in6_multi_mship *imm, *nimm;

        for (in6p = head; in6p != NULL; in6p = LIST_NEXT(in6p, inp_list)) {
                if (in6p->in6p_flags & INP_PLACEMARKER)
                        continue;
                im6o = in6p->in6p_moptions;
                if ((in6p->inp_vflag & INP_IPV6) &&
                    im6o) {
                        /*
                         * Unselect the outgoing interface if it is being
                         * detached.
                         */
                        if (im6o->im6o_multicast_ifp == ifp)
                                im6o->im6o_multicast_ifp = NULL;

                        /*
                         * Drop multicast group membership if we joined
                         * through the interface being detached.
                         * XXX controversial - is it really legal for kernel
                         * to force this?
                         */
                        for (imm = im6o->im6o_memberships.lh_first;
                             imm != NULL; imm = nimm) {
                                nimm = imm->i6mm_chain.le_next;
                                if (imm->i6mm_maddr->in6m_ifp == ifp) {
                                        LIST_REMOVE(imm, i6mm_chain);
                                        in6_delmulti(imm->i6mm_maddr);
                                        free(imm, M_IPMADDR);
                                }
                        }
                }
        }
}

/*
 * Check for alternatives when higher level complains
 * about service problems.  For now, invalidate cached
 * routing information.  If the route was created dynamically
 * (by a redirect), time to try a default gateway again.
 */
void
in6_losing(struct inpcb *in6p)
{
        struct rtentry *rt;
        struct rt_addrinfo info;

        if ((rt = in6p->in6p_route.ro_rt) != NULL) {
                bzero((caddr_t)&info, sizeof(info));
                info.rti_flags = rt->rt_flags;
                info.rti_info[RTAX_DST] = rt_key(rt);
                info.rti_info[RTAX_GATEWAY] = rt->rt_gateway;
                info.rti_info[RTAX_NETMASK] = rt_mask(rt);
                rt_missmsg(RTM_LOSING, &info, rt->rt_flags, 0);
                if (rt->rt_flags & RTF_DYNAMIC)
                        rtrequest1(RTM_DELETE, &info, NULL);
                in6p->in6p_route.ro_rt = NULL;
                rtfree(rt);
                /*
                 * A new route can be allocated
                 * the next time output is attempted.
                 */
        }
}

/*
 * After a routing change, flush old routing
 * and allocate a (hopefully) better one.
 */
void
in6_rtchange(struct inpcb *inp, int errno)
{
        if (inp->in6p_route.ro_rt) {
                rtfree(inp->in6p_route.ro_rt);
                inp->in6p_route.ro_rt = 0;
                /*
                 * A new route can be allocated the next time
                 * output is attempted.
                 */
        }
}

/*
 * Lookup PCB in hash list.
 */
struct inpcb *
in6_pcblookup_hash(struct inpcbinfo *pcbinfo, struct in6_addr *faddr,
                   u_int fport_arg, struct in6_addr *laddr, u_int lport_arg,
                   int wildcard, struct ifnet *ifp)
{
        struct inpcbhead *head;
        struct inpcb *inp;
        u_short fport = fport_arg, lport = lport_arg;
        int faith;

        if (faithprefix_p != NULL)
                faith = (*faithprefix_p)(laddr);
        else
                faith = 0;

        /*
         * First look for an exact match.
         */
        head = &pcbinfo->hashbase[INP_PCBCONNHASH(faddr->s6_addr32[3] /* XXX */,
                                              fport,
                                              laddr->s6_addr32[3], /* XXX JH */
                                              lport,
                                              pcbinfo->hashmask)];
        LIST_FOREACH(inp, head, inp_hash) {
                if ((inp->inp_vflag & INP_IPV6) == 0)
                        continue;
                if (IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, faddr) &&
                    IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, laddr) &&
                    inp->inp_fport == fport &&
                    inp->inp_lport == lport) {
                        /*
                         * Found.
                         */
                        return (inp);
                }
        }
        if (wildcard) {
                struct inpcontainerhead *chead;
                struct inpcontainer *ic;
                struct inpcb *local_wild = NULL;

                chead = &pcbinfo->wildcardhashbase[INP_PCBWILDCARDHASH(lport,
                    pcbinfo->wildcardhashmask)];
                LIST_FOREACH(ic, chead, ic_list) {
                        inp = ic->ic_inp;

                        if (!(inp->inp_vflag & INP_IPV6))
                                continue;
                        if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr) &&
                            inp->inp_lport == lport) {
                                if (faith && (inp->inp_flags & INP_FAITH) == 0)
                                        continue;
                                if (IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr,
                                                       laddr))
                                        return (inp);
                                else if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr))
                                        local_wild = inp;
                        }
                }
                return (local_wild);
        }

        /*
         * Not found.
         */
        return (NULL);
}

void
init_sin6(struct sockaddr_in6 *sin6, struct mbuf *m)
{
        struct ip6_hdr *ip;

        ip = mtod(m, struct ip6_hdr *);
        bzero(sin6, sizeof(*sin6));
        sin6->sin6_len = sizeof(*sin6);
        sin6->sin6_family = AF_INET6;
        sin6->sin6_addr = ip->ip6_src;
        if (IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
                sin6->sin6_addr.s6_addr16[1] = 0;
        sin6->sin6_scope_id =
                (m->m_pkthdr.rcvif && IN6_IS_SCOPE_LINKLOCAL(&sin6->sin6_addr))
                ? m->m_pkthdr.rcvif->if_index : 0;

        return;
}