xnu-2782.40.9.tar.gz

[apple/xnu.git] / bsd / netinet6 / raw_ip6.c

/*
 * Copyright (c) 2000-2014 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * 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.
 *
 * $FreeBSD: src/sys/netinet6/raw_ip6.c,v 1.7.2.4 2001/07/29 19:32:40 ume Exp $
 */

/*
 * Copyright (c) 1982, 1986, 1988, 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.
 *
 *	@(#)raw_ip.c	8.2 (Berkeley) 1/4/94
 */
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/mcache.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/protosw.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/systm.h>

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

#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet/in_pcb.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/nd6.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/scope6_var.h>
#include <netinet6/raw_ip6.h>
#include <netinet6/ip6_fw.h>

#if IPSEC
#include <netinet6/ipsec.h>
#include <netinet6/ipsec6.h>
#endif /*IPSEC*/

#if NECP
#include <net/necp.h>
#endif

/*
 * Raw interface to IP6 protocol.
 */

extern struct	inpcbhead ripcb;
extern struct	inpcbinfo ripcbinfo;
extern u_int32_t	rip_sendspace;
extern u_int32_t	rip_recvspace;

struct rip6stat rip6stat;

/*
 * Setup generic address and protocol structures
 * for raw_input routine, then pass them along with
 * mbuf chain.
 */
int
rip6_input(
	struct	mbuf **mp,
	int	*offp,
	int	proto)
{
	struct mbuf *m = *mp;
	struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
	struct inpcb *in6p;
	struct inpcb *last = 0;
	struct mbuf *opts = NULL;
	struct sockaddr_in6 rip6src;
	int ret;
	struct ifnet *ifp = m->m_pkthdr.rcvif;

	/* Expect 32-bit aligned data pointer on strict-align platforms */
	MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);

	rip6stat.rip6s_ipackets++;

	init_sin6(&rip6src, m); /* general init */

	lck_rw_lock_shared(ripcbinfo.ipi_lock);
	LIST_FOREACH(in6p, &ripcb, inp_list) {
		if ((in6p->in6p_vflag & INP_IPV6) == 0)
			continue;
		if (in6p->in6p_ip6_nxt &&
		    in6p->in6p_ip6_nxt != proto)
			continue;
		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr) &&
		    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_laddr, &ip6->ip6_dst))
			continue;
		if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr) &&
		    !IN6_ARE_ADDR_EQUAL(&in6p->in6p_faddr, &ip6->ip6_src))
			continue;

		if (inp_restricted_recv(in6p, ifp))
			continue;

		if (proto == IPPROTO_ICMPV6 || in6p->in6p_cksum != -1) {
			rip6stat.rip6s_isum++;
			if (in6_cksum(m, ip6->ip6_nxt, *offp,
			    m->m_pkthdr.len - *offp)) {
				rip6stat.rip6s_badsum++;
				continue;
			}
		}
		if (last) {
			struct mbuf *n = m_copy(m, 0, (int)M_COPYALL);

#if NECP
			if (n && !necp_socket_is_allowed_to_send_recv_v6(in6p, 0, 0, &ip6->ip6_dst, &ip6->ip6_src, ifp, NULL)) {
				m_freem(n);
				/* do not inject data into pcb */
			} else
#endif /* NECP */
			if (n) {
				if ((last->in6p_flags & INP_CONTROLOPTS) != 0 ||
				    (last->in6p_socket->so_options & SO_TIMESTAMP) != 0 ||
				    (last->in6p_socket->so_options & SO_TIMESTAMP_MONOTONIC) != 0) {
					ret = ip6_savecontrol(last, n, &opts);
					if (ret != 0) {
						m_freem(n);
						m_freem(opts);
						last = in6p;
						continue;
					} 
				}
				/* strip intermediate headers */
				m_adj(n, *offp);
				so_recv_data_stat(last->in6p_socket, m, 0);
				if (sbappendaddr(&last->in6p_socket->so_rcv,
						(struct sockaddr *)&rip6src,
						 n, opts, NULL) == 0) {
					rip6stat.rip6s_fullsock++;
				} else
					sorwakeup(last->in6p_socket);
				opts = NULL;
			}
		}
		last = in6p;
	}
	
#if NECP
	if (last && !necp_socket_is_allowed_to_send_recv_v6(in6p, 0, 0, &ip6->ip6_dst, &ip6->ip6_src, ifp, NULL)) {
		m_freem(m);
		ip6stat.ip6s_delivered--;
		/* do not inject data into pcb */
	} else
#endif /* NECP */
	if (last) {
		if ((last->in6p_flags & INP_CONTROLOPTS) != 0 ||
		    (last->in6p_socket->so_options & SO_TIMESTAMP) != 0 ||
		    (last->in6p_socket->so_options & SO_TIMESTAMP_MONOTONIC) != 0) {
			ret = ip6_savecontrol(last, m, &opts);
			if (ret != 0) {
				m_freem(m);
				m_freem(opts);
				ip6stat.ip6s_delivered--;
				goto unlock;
			}
				
		}
		/* strip intermediate headers */
		m_adj(m, *offp);
		so_recv_data_stat(last->in6p_socket, m, 0);
		if (sbappendaddr(&last->in6p_socket->so_rcv,
				(struct sockaddr *)&rip6src, m, opts, NULL) == 0) {
			rip6stat.rip6s_fullsock++;
		} else
			sorwakeup(last->in6p_socket);
	} else {
		rip6stat.rip6s_nosock++;
		if (m->m_flags & M_MCAST)
			rip6stat.rip6s_nosockmcast++;
		if (proto == IPPROTO_NONE)
			m_freem(m);
		else {
			char *prvnxtp = ip6_get_prevhdr(m, *offp); /* XXX */
			icmp6_error(m, ICMP6_PARAM_PROB,
				    ICMP6_PARAMPROB_NEXTHEADER,
				    prvnxtp - mtod(m, char *));
		}
		ip6stat.ip6s_delivered--;
	}

unlock:
	lck_rw_done(ripcbinfo.ipi_lock);

	return IPPROTO_DONE;
}

void
rip6_ctlinput(
	int cmd,
	struct sockaddr *sa,
	void *d)
{
	struct ip6_hdr *ip6;
	struct mbuf *m;
	void *cmdarg = NULL;
	int off = 0;
	struct ip6ctlparam *ip6cp = NULL;
	const struct sockaddr_in6 *sa6_src = NULL;
	void (*notify)(struct inpcb *, int) = in6_rtchange;

	if (sa->sa_family != AF_INET6 ||
	    sa->sa_len != sizeof(struct sockaddr_in6))
		return;

	if ((unsigned)cmd >= PRC_NCMDS)
		return;
	if (PRC_IS_REDIRECT(cmd))
		notify = in6_rtchange, d = NULL;
	else if (cmd == PRC_HOSTDEAD)
		d = NULL;
	else if (inet6ctlerrmap[cmd] == 0)
		return;

	/* if the parameter is from icmp6, decode it. */
	if (d != NULL) {
		ip6cp = (struct ip6ctlparam *)d;
		m = ip6cp->ip6c_m;
		ip6 = ip6cp->ip6c_ip6;
		off = ip6cp->ip6c_off;
		cmdarg = ip6cp->ip6c_cmdarg;
		sa6_src = ip6cp->ip6c_src;
	} else {
		m = NULL;
		ip6 = NULL;
		sa6_src = &sa6_any;
	}

	(void) in6_pcbnotify(&ripcbinfo, sa, 0, (const struct sockaddr *)sa6_src,
			     0, cmd, cmdarg, notify);
}

/*
 * Generate IPv6 header and pass packet to ip6_output.
 * Tack on options user may have setup with control call.
 */
int
rip6_output(
	struct mbuf *m,
	struct socket *so,
	struct sockaddr_in6 *dstsock,
	struct mbuf *control,
	int israw)
{
	struct in6_addr *dst;
	struct ip6_hdr *ip6;
	struct inpcb *in6p;
	u_int	plen = m->m_pkthdr.len;
	int error = 0;
	struct ip6_pktopts opt, *optp = NULL;
	struct ip6_moptions *im6o = NULL;
	struct ifnet *oifp = NULL;
	int type = 0, code = 0;		/* for ICMPv6 output statistics only */
	mbuf_svc_class_t msc = MBUF_SC_UNSPEC;
	struct ip6_out_args ip6oa =
	    { IFSCOPE_NONE, { 0 }, IP6OAF_SELECT_SRCIF, 0 };
	int flags = IPV6_OUTARGS;

	in6p = sotoin6pcb(so);

	if (in6p == NULL
#if NECP
		|| (necp_socket_should_use_flow_divert(in6p))
#endif /* NECP */
		) {
		if (in6p == NULL)
			error = EINVAL;
		else
			error = EPROTOTYPE;
		goto bad;
	}
	if (dstsock != NULL && IN6_IS_ADDR_V4MAPPED(&dstsock->sin6_addr)) {
		error = EINVAL;
		goto bad;
	}

	if (in6p->inp_flags & INP_BOUND_IF) {
		ip6oa.ip6oa_boundif = in6p->inp_boundifp->if_index;
		ip6oa.ip6oa_flags |= IP6OAF_BOUND_IF;
	}
	if (INP_NO_CELLULAR(in6p))
		ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR;
	if (INP_NO_EXPENSIVE(in6p))
		ip6oa.ip6oa_flags |= IP6OAF_NO_EXPENSIVE;
	if (INP_AWDL_UNRESTRICTED(in6p))
		ip6oa.ip6oa_flags |= IP6OAF_AWDL_UNRESTRICTED;

	dst = &dstsock->sin6_addr;
	if (control) {
		msc = mbuf_service_class_from_control(control);

		if ((error = ip6_setpktopts(control, &opt, NULL,
		    SOCK_PROTO(so))) != 0)
			goto bad;
		optp = &opt;
	} else
		optp = in6p->in6p_outputopts;

	/*
	 * For an ICMPv6 packet, we should know its type and code
	 * to update statistics.
	 */
	if (SOCK_PROTO(so) == IPPROTO_ICMPV6) {
		struct icmp6_hdr *icmp6;
		if (m->m_len < sizeof(struct icmp6_hdr) &&
		    (m = m_pullup(m, sizeof(struct icmp6_hdr))) == NULL) {
			error = ENOBUFS;
			goto bad;
		}
		icmp6 = mtod(m, struct icmp6_hdr *);
		type = icmp6->icmp6_type;
		code = icmp6->icmp6_code;
	}

	if (in6p->inp_flowhash == 0)
		in6p->inp_flowhash = inp_calc_flowhash(in6p);
	/* update flowinfo - RFC 6437 */
	if (in6p->inp_flow == 0 && in6p->in6p_flags & IN6P_AUTOFLOWLABEL) {
		in6p->inp_flow &= ~IPV6_FLOWLABEL_MASK;
		in6p->inp_flow |=
		    (htonl(in6p->inp_flowhash) & IPV6_FLOWLABEL_MASK);
	}

	M_PREPEND(m, sizeof(*ip6), M_WAIT);
	if (m == NULL) {
		error = ENOBUFS;
		goto bad;
	}
	ip6 = mtod(m, struct ip6_hdr *);

	/*
	 * Next header might not be ICMP6 but use its pseudo header anyway.
	 */
	ip6->ip6_dst = *dst;

	im6o = in6p->in6p_moptions;

	/*
	 * If the scope of the destination is link-local, embed the interface
	 * index in the address.
	 *
	 * XXX advanced-api value overrides sin6_scope_id
	 */
	if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
		struct in6_pktinfo *pi;
		struct ifnet *im6o_multicast_ifp = NULL;

		if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) && im6o != NULL) {
			IM6O_LOCK(im6o);
			im6o_multicast_ifp = im6o->im6o_multicast_ifp;
			IM6O_UNLOCK(im6o);
		}
		/*
		 * XXX Boundary check is assumed to be already done in
		 * ip6_setpktoptions().
		 */
		ifnet_head_lock_shared();
		if (optp && (pi = optp->ip6po_pktinfo) && pi->ipi6_ifindex) {
			ip6->ip6_dst.s6_addr16[1] = htons(pi->ipi6_ifindex);
			oifp = ifindex2ifnet[pi->ipi6_ifindex];
			if (oifp != NULL)
				ifnet_reference(oifp);
		} else if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) &&
		    im6o != NULL && im6o_multicast_ifp != NULL) {
			oifp = im6o_multicast_ifp;
			ifnet_reference(oifp);
			ip6->ip6_dst.s6_addr16[1] = htons(oifp->if_index);
		} else if (dstsock->sin6_scope_id) {
			/* 
			 * boundary check 
			 *
			 * Sinced stsock->sin6_scope_id is unsigned, we don't
			 * need to check if it's < 0
			 */
			if (if_index < dstsock->sin6_scope_id) {
				error = ENXIO;  /* XXX EINVAL? */
				ifnet_head_done();
				goto bad;
			}
			ip6->ip6_dst.s6_addr16[1]
				= htons(dstsock->sin6_scope_id & 0xffff);/*XXX*/
		}
		ifnet_head_done();
	}

	/*
	 * Source address selection.
	 */
	{
		struct in6_addr *in6a;
		struct in6_addr	storage;
		u_short index = 0;

		if (israw != 0 && optp && optp->ip6po_pktinfo && !IN6_IS_ADDR_UNSPECIFIED(&optp->ip6po_pktinfo->ipi6_addr)) {
			in6a = &optp->ip6po_pktinfo->ipi6_addr;
			flags |= IPV6_FLAG_NOSRCIFSEL;
		} else if ((in6a = in6_selectsrc(dstsock, optp, in6p,
		    &in6p->in6p_route, NULL, &storage, ip6oa.ip6oa_boundif,
		    &error)) == 0) {
			if (error == 0)
				error = EADDRNOTAVAIL;
			goto bad;
		} else {
			ip6oa.ip6oa_flags |= IP6OAF_BOUND_SRCADDR;
		}
		ip6->ip6_src = *in6a;
		if (in6p->in6p_route.ro_rt != NULL) {
			RT_LOCK(in6p->in6p_route.ro_rt);
			if (in6p->in6p_route.ro_rt->rt_ifp != NULL)
				index = in6p->in6p_route.ro_rt->rt_ifp->if_index;
			RT_UNLOCK(in6p->in6p_route.ro_rt);
			if (oifp != NULL)
				ifnet_release(oifp);
			ifnet_head_lock_shared();
			if (index == 0 || if_index < index) {
				panic("bad if_index on interface from route");
			}
			oifp = ifindex2ifnet[index];
			if (oifp != NULL)
				ifnet_reference(oifp);
			ifnet_head_done();
		}
	}
	ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
		(in6p->inp_flow & IPV6_FLOWINFO_MASK);
	ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
		(IPV6_VERSION & IPV6_VERSION_MASK);
	/* ip6_plen will be filled in ip6_output, so not fill it here. */
	ip6->ip6_nxt = in6p->in6p_ip6_nxt;
	ip6->ip6_hlim = in6_selecthlim(in6p, oifp);

	if (SOCK_PROTO(so) == IPPROTO_ICMPV6 || in6p->in6p_cksum != -1) {
		struct mbuf *n;
		int off;
		u_int16_t *p;

		/* compute checksum */
		if (SOCK_PROTO(so) == IPPROTO_ICMPV6)
			off = offsetof(struct icmp6_hdr, icmp6_cksum);
		else
			off = in6p->in6p_cksum;
		if (plen < (unsigned int)(off + 1)) {
			error = EINVAL;
			goto bad;
		}
		off += sizeof(struct ip6_hdr);

		n = m;
		while (n && n->m_len <= off) {
			off -= n->m_len;
			n = n->m_next;
		}
		if (!n)
			goto bad;
		p = (u_int16_t *)(void *)(mtod(n, caddr_t) + off);
		*p = 0;
		*p = in6_cksum(m, ip6->ip6_nxt, sizeof(*ip6), plen);
	}
	
#if NECP
	{
		necp_kernel_policy_id policy_id;
		if (!necp_socket_is_allowed_to_send_recv_v6(in6p, 0, 0, &ip6->ip6_src, &ip6->ip6_dst, NULL, &policy_id)) {
			error = EHOSTUNREACH;
			goto bad;
		}

		necp_mark_packet_from_socket(m, in6p, policy_id);
	}
#endif /* NECP */
	
#if IPSEC
	if (in6p->in6p_sp != NULL && ipsec_setsocket(m, so) != 0) {
		error = ENOBUFS;
		goto bad;
	}
#endif /*IPSEC*/

	if (ROUTE_UNUSABLE(&in6p->in6p_route))
		ROUTE_RELEASE(&in6p->in6p_route);

	if (oifp != NULL) {
		ifnet_release(oifp);
		oifp = NULL;
	}

	set_packet_service_class(m, so, msc, PKT_SCF_IPV6);
	m->m_pkthdr.pkt_flowsrc = FLOWSRC_INPCB;
	m->m_pkthdr.pkt_flowid = in6p->inp_flowhash;
	m->m_pkthdr.pkt_flags |= (PKTF_FLOW_ID | PKTF_FLOW_LOCALSRC |
	    PKTF_FLOW_RAWSOCK);
	m->m_pkthdr.pkt_proto = in6p->in6p_ip6_nxt;

	if (im6o != NULL)
		IM6O_ADDREF(im6o);

	error = ip6_output(m, optp, &in6p->in6p_route, flags, im6o,
	    &oifp, &ip6oa);

	if (im6o != NULL)
		IM6O_REMREF(im6o);

	if (in6p->in6p_route.ro_rt != NULL) {
		struct rtentry *rt = in6p->in6p_route.ro_rt;
		struct ifnet *outif;

		if ((rt->rt_flags & RTF_MULTICAST) ||
		    in6p->in6p_socket == NULL ||
		    !(in6p->in6p_socket->so_state & SS_ISCONNECTED)) {
			rt = NULL;	/* unusable */
		}
		/*
		 * Always discard the cached route for unconnected
		 * socket or if it is a multicast route.
		 */
		if (rt == NULL)
			ROUTE_RELEASE(&in6p->in6p_route);

		/*
		 * If this is a connected socket and the destination
		 * route is not multicast, update outif with that of
		 * the route interface index used by IP.
		 */
		if (rt != NULL &&
		    (outif = rt->rt_ifp) != in6p->in6p_last_outifp)
			in6p->in6p_last_outifp = outif;
	} else {
		ROUTE_RELEASE(&in6p->in6p_route);
	}

	/*
	 * If output interface was cellular/expensive, and this socket is
	 * denied access to it, generate an event.
	 */
	if (error != 0 && (ip6oa.ip6oa_retflags & IP6OARF_IFDENIED) &&
	    (INP_NO_CELLULAR(in6p) || INP_NO_EXPENSIVE(in6p)))
		soevent(in6p->inp_socket, (SO_FILT_HINT_LOCKED|
		    SO_FILT_HINT_IFDENIED));

	if (SOCK_PROTO(so) == IPPROTO_ICMPV6) {
		if (oifp)
			icmp6_ifoutstat_inc(oifp, type, code);
		icmp6stat.icp6s_outhist[type]++;
	} else
		rip6stat.rip6s_opackets++;

	goto freectl;

bad:
	if (m != NULL)
		m_freem(m);

freectl:
	if (optp == &opt && optp->ip6po_rthdr)
		ROUTE_RELEASE(&optp->ip6po_route);

	if (control != NULL) {
		if (optp == &opt)
			ip6_clearpktopts(optp, -1);
		m_freem(control);
	}
	if (oifp != NULL)
		ifnet_release(oifp);
	return(error);
}

#if IPFW2
__private_extern__ void
load_ip6fw(void)
{
	ip6_fw_init();
}
#endif

/*
 * Raw IPv6 socket option processing.
 */
int
rip6_ctloutput(
	struct socket *so,
	struct sockopt *sopt)
{
	int error, optval;

	/* Allow <SOL_SOCKET,SO_FLUSH> at this level */
	if (sopt->sopt_level == IPPROTO_ICMPV6)
		/*
		 * XXX: is it better to call icmp6_ctloutput() directly
		 * from protosw?
		 */
		return(icmp6_ctloutput(so, sopt));
	else if (sopt->sopt_level != IPPROTO_IPV6 &&
	    !(sopt->sopt_level == SOL_SOCKET && sopt->sopt_name == SO_FLUSH))
		return (EINVAL);

	error = 0;

	switch (sopt->sopt_dir) {
	case SOPT_GET:
		switch (sopt->sopt_name) {
#if IPFW2
		case IPV6_FW_ADD:
		case IPV6_FW_GET:
			if (ip6_fw_ctl_ptr == 0)
				load_ip6fw();
			if (ip6_fw_ctl_ptr)
				error = ip6_fw_ctl_ptr(sopt);
			else
				error = ENOPROTOOPT;
			break;
#endif
		case IPV6_CHECKSUM:
			error = ip6_raw_ctloutput(so, sopt);
			break;
		default:
			error = ip6_ctloutput(so, sopt);
			break;
		}
		break;

	case SOPT_SET:
		switch (sopt->sopt_name) {
#if IPFW2
		case IPV6_FW_ADD:
		case IPV6_FW_DEL:
		case IPV6_FW_FLUSH:
		case IPV6_FW_ZERO:
			if (ip6_fw_ctl_ptr == 0)
				load_ip6fw();
			if (ip6_fw_ctl_ptr)
				error = ip6_fw_ctl_ptr(sopt);
			else
				error = ENOPROTOOPT;
			break;
#endif

		case IPV6_CHECKSUM:
			error = ip6_raw_ctloutput(so, sopt);
			break;

		case SO_FLUSH:
			if ((error = sooptcopyin(sopt, &optval, sizeof (optval),
			    sizeof (optval))) != 0)
				break;

			error = inp_flush(sotoinpcb(so), optval);
			break;

		default:
			error = ip6_ctloutput(so, sopt);
			break;
		}
		break;
	}

	return (error);
}

static int
rip6_attach(struct socket *so, int proto, struct proc *p)
{
	struct inpcb *inp;
	int error;

	inp = sotoinpcb(so);
	if (inp)
		panic("rip6_attach");
	if ((error = proc_suser(p)) != 0)
		return error;

	error = soreserve(so, rip_sendspace, rip_recvspace);
	if (error)
		return error;
	error = in_pcballoc(so, &ripcbinfo, p);
	if (error)
		return error;
	inp = (struct inpcb *)so->so_pcb;
	inp->inp_vflag |= INP_IPV6;
	inp->in6p_ip6_nxt = (char)proto;
	inp->in6p_hops = -1;	/* use kernel default */
	inp->in6p_cksum = -1;
	MALLOC(inp->in6p_icmp6filt, struct icmp6_filter *,
	       sizeof(struct icmp6_filter), M_PCB, M_WAITOK);
	if (inp->in6p_icmp6filt == NULL)
		return (ENOMEM);
	ICMP6_FILTER_SETPASSALL(inp->in6p_icmp6filt);
	return 0;
}

static int
rip6_detach(struct socket *so)
{
	struct inpcb *inp;

	inp = sotoinpcb(so);
	if (inp == 0)
		panic("rip6_detach");
	/* xxx: RSVP */
	if (inp->in6p_icmp6filt) {
		FREE(inp->in6p_icmp6filt, M_PCB);
		inp->in6p_icmp6filt = NULL;
	}
	in6_pcbdetach(inp);
	return 0;
}

static int
rip6_abort(struct socket *so)
{
	soisdisconnected(so);
	return rip6_detach(so);
}

static int
rip6_disconnect(struct socket *so)
{
	struct inpcb *inp = sotoinpcb(so);

	if ((so->so_state & SS_ISCONNECTED) == 0)
		return ENOTCONN;
	inp->in6p_faddr = in6addr_any;
	return rip6_abort(so);
}

static int
rip6_bind(struct socket *so, struct sockaddr *nam, struct proc *p)
{
#pragma unused(p)
	struct inpcb *inp = sotoinpcb(so);
	struct sockaddr_in6 sin6;
	struct ifaddr *ifa = NULL;
	struct ifnet *outif = NULL;
	int error;

	if (inp == NULL
#if NECP
		|| (necp_socket_should_use_flow_divert(inp))
#endif /* NECP */
		)
		return (inp == NULL ? EINVAL : EPROTOTYPE);

	if (nam->sa_len != sizeof (struct sockaddr_in6))
		return (EINVAL);

	if (TAILQ_EMPTY(&ifnet_head) || SIN6(nam)->sin6_family != AF_INET6)
		return (EADDRNOTAVAIL);

	bzero(&sin6, sizeof (sin6));
	*(&sin6) = *SIN6(nam);

	if ((error = sa6_embedscope(&sin6, ip6_use_defzone)) != 0)
		return (error);

	/* Sanitize local copy for address searches */
	sin6.sin6_flowinfo = 0;
	sin6.sin6_scope_id = 0;
	sin6.sin6_port = 0;

	if (!IN6_IS_ADDR_UNSPECIFIED(&sin6.sin6_addr) &&
	    (ifa = ifa_ifwithaddr(SA(&sin6))) == 0)
		return (EADDRNOTAVAIL);
	if (ifa != NULL) {
		IFA_LOCK(ifa);
		if (((struct in6_ifaddr *)ifa)->ia6_flags &
		    (IN6_IFF_ANYCAST|IN6_IFF_NOTREADY|
		     IN6_IFF_DETACHED|IN6_IFF_DEPRECATED)) {
			IFA_UNLOCK(ifa);
			IFA_REMREF(ifa);
			return (EADDRNOTAVAIL);
		}
		outif = ifa->ifa_ifp;
		IFA_UNLOCK(ifa);
		IFA_REMREF(ifa);
	}
	inp->in6p_laddr = sin6.sin6_addr;
	inp->in6p_last_outifp = outif;
	return (0);
}

static int
rip6_connect(struct socket *so, struct sockaddr *nam, __unused struct proc *p)
{
	struct inpcb *inp = sotoinpcb(so);
	struct sockaddr_in6 *addr = (struct sockaddr_in6 *)(void *)nam;
	struct in6_addr *in6a = NULL;
	struct in6_addr storage;
	int error = 0;
#if ENABLE_DEFAULT_SCOPE
	struct sockaddr_in6 tmp;
#endif
	unsigned int ifscope;
	struct ifnet *outif = NULL;

	if (inp == NULL
#if NECP
		|| (necp_socket_should_use_flow_divert(inp))
#endif /* NECP */
		)
		return (inp == NULL ? EINVAL : EPROTOTYPE);
	if (nam->sa_len != sizeof(*addr))
		return EINVAL;
	if (TAILQ_EMPTY(&ifnet_head))
		return EADDRNOTAVAIL;
	if (addr->sin6_family != AF_INET6)
		return EAFNOSUPPORT;
#if ENABLE_DEFAULT_SCOPE
	if (addr->sin6_scope_id == 0) {	/* not change if specified  */
		/* avoid overwrites */
		tmp = *addr;
		addr = &tmp;
		addr->sin6_scope_id = scope6_addr2default(&addr->sin6_addr);
	}
#endif

	ifscope = (inp->inp_flags & INP_BOUND_IF) ?
	    inp->inp_boundifp->if_index : IFSCOPE_NONE;

	/* Source address selection. XXX: need pcblookup? */
	in6a = in6_selectsrc(addr, inp->in6p_outputopts, inp, &inp->in6p_route,
	    NULL, &storage, ifscope, &error);
	if (in6a == NULL)
		return (error ? error : EADDRNOTAVAIL);
	inp->in6p_laddr = *in6a;
	inp->in6p_faddr = addr->sin6_addr;
	if (inp->in6p_route.ro_rt != NULL)
		outif = inp->in6p_route.ro_rt->rt_ifp;
	inp->in6p_last_outifp = outif;
	soisconnected(so);
	return 0;
}

static int
rip6_shutdown(struct socket *so)
{
	socantsendmore(so);
	return 0;
}

static int
rip6_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
    struct mbuf *control, struct proc *p)
{
#pragma unused(flags, p)
	struct inpcb *inp = sotoinpcb(so);
	struct sockaddr_in6 tmp;
	struct sockaddr_in6 *dst = (struct sockaddr_in6 *)(void *)nam;
	int error = 0;

	if (inp == NULL
#if NECP
		|| (necp_socket_should_use_flow_divert(inp))
#endif /* NECP */
		) {
		if (inp == NULL)
			error = EINVAL;
		else
			error = EPROTOTYPE;
		goto bad;
	}

	/* always copy sockaddr to avoid overwrites */
	if (so->so_state & SS_ISCONNECTED) {
		if (nam != NULL) {
			error = EISCONN;
			goto bad;
		}
		/* XXX */
		bzero(&tmp, sizeof(tmp));
		tmp.sin6_family = AF_INET6;
		tmp.sin6_len = sizeof(struct sockaddr_in6);
		bcopy(&inp->in6p_faddr, &tmp.sin6_addr,
		      sizeof(struct in6_addr));
		dst = &tmp;
	} else {
		if (nam == NULL) {
			error = ENOTCONN;
			goto bad;
		}
		tmp = *(struct sockaddr_in6 *)(void *)nam;
		dst = &tmp;
	}
#if ENABLE_DEFAULT_SCOPE
	if (dst->sin6_scope_id == 0) {	/* not change if specified  */
		dst->sin6_scope_id = scope6_addr2default(&dst->sin6_addr);
	}
#endif
	return (rip6_output(m, so, dst, control, 1));

bad:
	VERIFY(error != 0);

	if (m != NULL)
		m_freem(m);
	if (control != NULL)
		m_freem(control);

	return (error);
}

struct pr_usrreqs rip6_usrreqs = {
	.pru_abort =		rip6_abort,
	.pru_attach =		rip6_attach,
	.pru_bind =		rip6_bind,
	.pru_connect =		rip6_connect,
	.pru_control =		in6_control,
	.pru_detach =		rip6_detach,
	.pru_disconnect =	rip6_disconnect,
	.pru_peeraddr =		in6_getpeeraddr,
	.pru_send =		rip6_send,
	.pru_shutdown =		rip6_shutdown,
	.pru_sockaddr =		in6_getsockaddr,
	.pru_sosend =		sosend,
	.pru_soreceive =	soreceive,
};

__private_extern__ struct pr_usrreqs icmp6_dgram_usrreqs = {
	.pru_abort =		rip6_abort,
	.pru_attach =		icmp6_dgram_attach,
	.pru_bind =		rip6_bind,
	.pru_connect =		rip6_connect,
	.pru_control =		in6_control,
	.pru_detach =		rip6_detach,
	.pru_disconnect =	rip6_disconnect,
	.pru_peeraddr =		in6_getpeeraddr,
	.pru_send =		icmp6_dgram_send,
	.pru_shutdown =		rip6_shutdown,
	.pru_sockaddr =		in6_getsockaddr,
	.pru_sosend =		sosend,
	.pru_soreceive =	soreceive,
};