in6_pcb.c

eCos操作系统源码

//==========================================================================
//
//      src/sys/netinet6/in6_pcb.c
//
//==========================================================================
//####BSDCOPYRIGHTBEGIN####
//
// -------------------------------------------
//
// Portions of this software may have been derived from OpenBSD, 
// FreeBSD or other sources, and are covered by the appropriate
// copyright disclaimers included herein.
//
// Portions created by Red Hat are
// Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
//
// -------------------------------------------
//
//####BSDCOPYRIGHTEND####
//==========================================================================

/*	$FreeBSD: src/sys/netinet6/in6_pcb.c,v 1.10.2.4 2001/08/13 16:26:17 ume Exp $	*/
/*	$KAME: in6_pcb.c,v 1.42 2001/11/13 03:09:44 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 <sys/param.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 <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>
#include <netinet6/scope6_var.h>

#ifdef IPSEC
#include <netinet6/ipsec.h>
#include <netinet6/ah.h>
#include <netkey/key.h>
#endif /* IPSEC */

struct	in6_addr zeroin6_addr;

int
in6_pcbbind(inp, nam, p)
	register struct inpcb *inp;
	struct sockaddr *nam;
	struct proc *p;
{
	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) {
		int error;

		sin6 = (struct sockaddr_in6 *)nam;
		if (nam->sa_len != sizeof(*sin6))
			return(EINVAL);
		/*
		 * family check.
		 */
		if (nam->sa_family != AF_INET6)
			return(EAFNOSUPPORT);

		if ((error = scope6_check_id(sin6, ip6_use_defzone)) != 0)
			return(error);
#ifndef SCOPEDROUTING
		/* this must be cleared for ifa_ifwithaddr() */
		sin6->sin6_scope_id = 0;
#endif

		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;

			/* GROSS */
			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, p)) != 0)
			return(e);
	}
	else {
		inp->inp_lport = lport;
		if (in_pcbinshash(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(inp, nam, plocal_addr6)
	register struct inpcb *inp;
	struct sockaddr *nam;
	struct in6_addr **plocal_addr6;
{
	register struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)nam;
	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);

	if ((error = scope6_check_id(sin6, ip6_use_defzone)) != 0)
		return(error);
#ifndef SCOPEDROUTING
	sin6->sin6_scope_id = 0;
#endif

	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;
	}
	{
		struct ifnet *ifp = NULL;

		*plocal_addr6 = in6_selectsrc(sin6, inp->in6p_outputopts,
					      inp->in6p_moptions,
					      &inp->in6p_route,
					      &ifp, &inp->in6p_laddr, &error);
		if (ifp && sin6->sin6_scope_id == 0 &&
		    (error = scope6_setzoneid(ifp, sin6)) != 0) { /* XXX */
			return(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.
		 */
	}

	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(inp, nam, p)
	register struct inpcb *inp;
	struct sockaddr *nam;
	struct proc *p;
{
	struct in6_addr *addr6;
	register 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_pcbinfo, &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, p);
			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_pcbrehash(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(dstsock, opts, mopts, ro, laddr, errorp)
	struct sockaddr_in6 *dstsock;
	struct ip6_pktopts *opts;
	struct ip6_moptions *mopts;
#ifdef NEW_STRUCT_ROUTE
	struct route *ro;
#else
	struct route_in6 *ro;
#endif
	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 = (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 ?*/
				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(in6p, ifp)
	struct in6pcb *in6p;
	struct ifnet *ifp;