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

/*
 * Copyright (c) 2008-2011 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@
 */

/*	$FreeBSD: src/sys/netinet6/ah_output.c,v 1.1.2.3 2001/07/03 11:01:49 ume Exp $	*/
/*	$KAME: ah_output.c,v 1.30 2001/02/21 00:50:53 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.
 */

/*
 * RFC1826/2402 authentication header.
 */

#define _IP_VHL

#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/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>

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

#include <netinet/in.h>

#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_var.h>

#if INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#endif

#include <netinet6/ipsec.h>
#if INET6
#include <netinet6/ipsec6.h>
#endif
#include <netinet6/ah.h>
#if INET6
#include <netinet6/ah6.h>
#endif
#include <netkey/key.h>
#include <netkey/keydb.h>

#include <net/net_osdep.h>

#if INET
static struct in_addr *ah4_finaldst(struct mbuf *);
#endif

extern lck_mtx_t *sadb_mutex;

/*
 * compute AH header size.
 * transport mode only.  for tunnel mode, we should implement
 * virtual interface, and control MTU/MSS by the interface MTU.
 */
size_t
ah_hdrsiz(isr)
	struct ipsecrequest *isr;
{

	/* sanity check */
	if (isr == NULL)
		panic("ah_hdrsiz: NULL was passed.\n");

	if (isr->saidx.proto != IPPROTO_AH)
		panic("unsupported mode passed to ah_hdrsiz");

#if 0
	{

		lck_mtx_lock(sadb_mutex);
		const struct ah_algorithm *algo;
		size_t hdrsiz;

		/*%%%%% this needs to change - no sav in ipsecrequest any more */
		if (isr->sav == NULL)
			goto estimate;
		if (isr->sav->state != SADB_SASTATE_MATURE
		 && isr->sav->state != SADB_SASTATE_DYING)
			goto estimate;
	
		/* we need transport mode AH. */
		algo = ah_algorithm_lookup(isr->sav->alg_auth);
		if (!algo)
			goto estimate;
	
		/*
		 * XXX
		 * right now we don't calcurate the padding size.  simply
		 * treat the padding size as constant, for simplicity.
		 *
		 * XXX variable size padding support
		 */
		hdrsiz = (((*algo->sumsiz)(isr->sav) + 3) & ~(4 - 1));
		if (isr->sav->flags & SADB_X_EXT_OLD)
			hdrsiz += sizeof(struct ah);
		else
			hdrsiz += sizeof(struct newah);
	
		lck_mtx_unlock(sadb_mutex);
		return hdrsiz;
	}

estimate:
#endif

    //lck_mtx_unlock(sadb_mutex);
	/* ASSUMING:
	 *	sizeof(struct newah) > sizeof(struct ah).
	 *	16 = (16 + 3) & ~(4 - 1).
	 */
	return sizeof(struct newah) + 16;
}

#if INET
/*
 * Modify the packet so that it includes the authentication data.
 * The mbuf passed must start with IPv4 header.
 *
 * assumes that the first mbuf contains IPv4 header + option only.
 * the function does not modify m.
 */
int
ah4_output(m, sav)
	struct mbuf *m;
	struct secasvar *sav;
{
	const struct ah_algorithm *algo;
	u_int32_t spi;
	u_char *ahdrpos;
	u_char *ahsumpos = NULL;
	size_t hlen = 0;	/*IP header+option in bytes*/
	size_t plen = 0;	/*AH payload size in bytes*/
	size_t ahlen = 0;	/*plen + sizeof(ah)*/
	struct ip *ip;
	struct in_addr dst = { 0 };
	struct in_addr *finaldst;
	int error;

	/* sanity checks */
	if ((sav->flags & SADB_X_EXT_OLD) == 0 && !sav->replay) {
		ip = mtod(m, struct ip *);
		ipseclog((LOG_DEBUG, "ah4_output: internal error: "
			"sav->replay is null: %x->%x, SPI=%u\n",
			(u_int32_t)ntohl(ip->ip_src.s_addr),
			(u_int32_t)ntohl(ip->ip_dst.s_addr),
			(u_int32_t)ntohl(sav->spi)));
		IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
		m_freem(m);
		return EINVAL;
	}

	algo = ah_algorithm_lookup(sav->alg_auth);
	if (!algo) {
		ipseclog((LOG_ERR, "ah4_output: unsupported algorithm: "
		    "SPI=%u\n", (u_int32_t)ntohl(sav->spi)));
		IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
		m_freem(m);
		return EINVAL;
	}
	spi = sav->spi;

	/*
	 * determine the size to grow.
	 */
	if (sav->flags & SADB_X_EXT_OLD) {
		/* RFC 1826 */
		plen = ((*algo->sumsiz)(sav) + 3) & ~(4 - 1); /*XXX pad to 8byte?*/
		ahlen = plen + sizeof(struct ah);
	} else {
		/* RFC 2402 */
		plen = ((*algo->sumsiz)(sav) + 3) & ~(4 - 1); /*XXX pad to 8byte?*/
		ahlen = plen + sizeof(struct newah);
	}

	/*
	 * grow the mbuf to accomodate AH.
	 */
	ip = mtod(m, struct ip *);
#ifdef _IP_VHL
	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
#else
	hlen = ip->ip_hl << 2;
#endif

	if (m->m_len != hlen)
		panic("ah4_output: assumption failed (first mbuf length)");
	if (M_LEADINGSPACE(m->m_next) < ahlen) {
		struct mbuf *n;
		MGET(n, M_DONTWAIT, MT_DATA);
		if (!n) {
			ipseclog((LOG_DEBUG, "ENOBUFS in ah4_output %d\n",
			    __LINE__));
			m_freem(m);
			return ENOBUFS;
		}
		n->m_len = ahlen;
		n->m_next = m->m_next;
		m->m_next = n;
		m->m_pkthdr.len += ahlen;
		ahdrpos = mtod(n, u_char *);
	} else {
		m->m_next->m_len += ahlen;
		m->m_next->m_data -= ahlen;
		m->m_pkthdr.len += ahlen;
		ahdrpos = mtod(m->m_next, u_char *);
	}

	ip = mtod(m, struct ip *);	/*just to be sure*/

	/*
	 * initialize AH.
	 */
	if (sav->flags & SADB_X_EXT_OLD) {
		struct ah *ahdr;

		ahdr = (struct ah *)(void *)ahdrpos;
		ahsumpos = (u_char *)(ahdr + 1);
		ahdr->ah_len = plen >> 2;
		ahdr->ah_nxt = ip->ip_p;
		ahdr->ah_reserve = htons(0);
		ahdr->ah_spi = spi;
		bzero(ahdr + 1, plen);
	} else {
		struct newah *ahdr;

		ahdr = (struct newah *)(void *)ahdrpos;
		ahsumpos = (u_char *)(ahdr + 1);
		ahdr->ah_len = (plen >> 2) + 1;	/* plus one for seq# */
		ahdr->ah_nxt = ip->ip_p;
		ahdr->ah_reserve = htons(0);
		ahdr->ah_spi = spi;
		if (sav->replay->count == ~0) {
			if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
				/* XXX Is it noisy ? */
				ipseclog((LOG_WARNING,
				    "replay counter overflowed. %s\n",
				    ipsec_logsastr(sav)));
				IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
				m_freem(m);
				return EINVAL;
			}
		}
		lck_mtx_lock(sadb_mutex);
		sav->replay->count++;
		lck_mtx_unlock(sadb_mutex);
		/*
		 * XXX sequence number must not be cycled, if the SA is
		 * installed by IKE daemon.
		 */
		ahdr->ah_seq = htonl(sav->replay->count);
		bzero(ahdr + 1, plen);
	}

	/*
	 * modify IPv4 header.
	 */
	ip->ip_p = IPPROTO_AH;
	if (ahlen < (IP_MAXPACKET - ntohs(ip->ip_len)))
		ip->ip_len = htons(ntohs(ip->ip_len) + ahlen);
	else {
		ipseclog((LOG_ERR, "IPv4 AH output: size exceeds limit\n"));
		IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
		m_freem(m);
		return EMSGSIZE;
	}

	/*
	 * If there is source routing option, update destination field in
	 * the IPv4 header to the final destination.
	 * Note that we do not need to update source routing option itself
	 * (as done in IPv4 AH processing -- see ip6_output()), since
	 * source routing option is not part of the ICV computation.
	 */
	finaldst = ah4_finaldst(m);
	if (finaldst) {
		dst.s_addr = ip->ip_dst.s_addr;
		ip->ip_dst.s_addr = finaldst->s_addr;
	}

	/*
	 * calcurate the checksum, based on security association
	 * and the algorithm specified.
	 */
	error = ah4_calccksum(m, (caddr_t)ahsumpos, plen, algo, sav);
	if (error) {
		ipseclog((LOG_ERR,
		    "error after ah4_calccksum, called from ah4_output"));
		m_freem(m);
		m = NULL;
		IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
		return error;
	}

	if (finaldst) {
		ip = mtod(m, struct ip *);	/*just to make sure*/
		ip->ip_dst.s_addr = dst.s_addr;
	}
	lck_mtx_lock(sadb_stat_mutex);
	ipsecstat.out_success++;
	ipsecstat.out_ahhist[sav->alg_auth]++;
	lck_mtx_unlock(sadb_stat_mutex);
	key_sa_recordxfer(sav, m);

	return 0;
}
#endif

/* Calculate AH length */
int
ah_hdrlen(sav)
	struct secasvar *sav;
{
	const struct ah_algorithm *algo;
	int plen, ahlen;
	
	algo = ah_algorithm_lookup(sav->alg_auth);
	if (!algo)
		return 0;
	if (sav->flags & SADB_X_EXT_OLD) {
		/* RFC 1826 */
		plen = ((*algo->sumsiz)(sav) + 3) & ~(4 - 1);	/*XXX pad to 8byte?*/
		ahlen = plen + sizeof(struct ah);
	} else {
		/* RFC 2402 */
		plen = ((*algo->sumsiz)(sav) + 3) & ~(4 - 1);	/*XXX pad to 8byte?*/
		ahlen = plen + sizeof(struct newah);
	}

	return(ahlen);
}

#if INET6
/*
 * Fill in the Authentication Header and calculate checksum.
 */
int
ah6_output(m, nexthdrp, md, sav)
	struct mbuf *m;
	u_char *nexthdrp;
	struct mbuf *md;
	struct secasvar *sav;
{
	struct mbuf *mprev;
	struct mbuf *mah;
	const struct ah_algorithm *algo;
	u_int32_t spi;
	u_char *ahsumpos = NULL;
	size_t plen;	/*AH payload size in bytes*/
	int error = 0;
	int ahlen;
	struct ip6_hdr *ip6;

	if (m->m_len < sizeof(struct ip6_hdr)) {
		ipseclog((LOG_DEBUG, "ah6_output: first mbuf too short\n"));
		m_freem(m);
		return EINVAL;
	}

	ahlen = ah_hdrlen(sav);
	if (ahlen == 0)
		return 0;

	for (mprev = m; mprev && mprev->m_next != md; mprev = mprev->m_next)
		;
	if (!mprev || mprev->m_next != md) {
		ipseclog((LOG_DEBUG, "ah6_output: md is not in chain\n"));
		m_freem(m);
		return EINVAL;
	}

	MGET(mah, M_DONTWAIT, MT_DATA);
	if (!mah) {
		m_freem(m);
		return ENOBUFS;
	}
	if (ahlen > MLEN) {
		MCLGET(mah, M_DONTWAIT);
		if ((mah->m_flags & M_EXT) == 0) {
			m_free(mah);
			m_freem(m);
			return ENOBUFS;
		}
	}
	mah->m_len = ahlen;
	mah->m_next = md;
	mprev->m_next = mah;
	m->m_pkthdr.len += ahlen;

	/* fix plen */
	if (m->m_pkthdr.len - sizeof(struct ip6_hdr) > IPV6_MAXPACKET) {
		ipseclog((LOG_ERR,
		    "ip6_output: AH with IPv6 jumbogram is not supported\n"));
		m_freem(m);
		return EINVAL;
	}
	ip6 = mtod(m, struct ip6_hdr *);
	ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));

	if ((sav->flags & SADB_X_EXT_OLD) == 0 && !sav->replay) {
		ipseclog((LOG_DEBUG, "ah6_output: internal error: "
			  "sav->replay is null: SPI=%u\n",
			  (u_int32_t)ntohl(sav->spi)));
		IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
		m_freem(m);
		return EINVAL;
	}

	algo = ah_algorithm_lookup(sav->alg_auth);
	if (!algo) {
		ipseclog((LOG_ERR, "ah6_output: unsupported algorithm: "
		    "SPI=%u\n", (u_int32_t)ntohl(sav->spi)));
		IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
		m_freem(m);
		return EINVAL;
	}
	spi = sav->spi;

	/*
	 * initialize AH.
	 */
	if (sav->flags & SADB_X_EXT_OLD) {
		struct ah *ahdr = mtod(mah, struct ah *);

		plen = mah->m_len - sizeof(struct ah);
		ahsumpos = (u_char *)(ahdr + 1);
		ahdr->ah_nxt = *nexthdrp;
		*nexthdrp = IPPROTO_AH;
		ahdr->ah_len = plen >> 2;
		ahdr->ah_reserve = htons(0);
		ahdr->ah_spi = spi;
		bzero(ahdr + 1, plen);
	} else {
		struct newah *ahdr = mtod(mah, struct newah *);

		plen = mah->m_len - sizeof(struct newah);
		ahsumpos = (u_char *)(ahdr + 1);
		ahdr->ah_nxt = *nexthdrp;
		*nexthdrp = IPPROTO_AH;
		ahdr->ah_len = (plen >> 2) + 1;	/* plus one for seq# */
		ahdr->ah_reserve = htons(0);
		ahdr->ah_spi = spi;
		if (sav->replay->count == ~0) {
			if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
				/* XXX Is it noisy ? */
				ipseclog((LOG_WARNING,
				     "replay counter overflowed. %s\n",
				    ipsec_logsastr(sav)));
				IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
				m_freem(m);
				return EINVAL;
			}
		}
		lck_mtx_lock(sadb_mutex);
		sav->replay->count++;
		lck_mtx_unlock(sadb_mutex);
		/*
		 * XXX sequence number must not be cycled, if the SA is
		 * installed by IKE daemon.
		 */
		ahdr->ah_seq = htonl(sav->replay->count);
		bzero(ahdr + 1, plen);
	}

	/*
	 * calcurate the checksum, based on security association
	 * and the algorithm specified.
	 */
	error = ah6_calccksum(m, (caddr_t)ahsumpos, plen, algo, sav);
	if (error) {
		IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
		m_freem(m);
	} else {
		IPSEC_STAT_INCREMENT(ipsec6stat.out_success);
		key_sa_recordxfer(sav, m);
	}
	IPSEC_STAT_INCREMENT(ipsec6stat.out_ahhist[sav->alg_auth]);

	return(error);
}
#endif

#if INET
/*
 * Find the final destination if there is loose/strict source routing option.
 * Returns NULL if there's no source routing options.
 * Returns NULL on errors too.
 * Note that this function will return a pointer INTO the given parameter,
 * struct mbuf *m.
 * The mbuf must be pulled up toward, at least, ip option part.
 */
static struct in_addr *
ah4_finaldst(m)
	struct mbuf *m;
{
	struct ip *ip;
	int optlen;
	u_char *q;
	int i;
	int hlen;

	if (!m)
		panic("ah4_finaldst: m == NULL");
	ip = mtod(m, struct ip *);
#ifdef _IP_VHL
	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
#else
	hlen = ip->ip_hl << 2;
#endif

	if (m->m_len < hlen) {
		ipseclog((LOG_DEBUG,
		    "ah4_finaldst: parameter mbuf wrong (not pulled up)\n"));
		return NULL;
	}

	if (hlen == sizeof(struct ip))
		return NULL;

	optlen = hlen - sizeof(struct ip);
	if (optlen < 0) {
		ipseclog((LOG_DEBUG, "ah4_finaldst: wrong optlen %d\n",
		    optlen));
		return NULL;
	}

	q = (u_char *)(ip + 1);
	i = 0;
	while (i < optlen) {
		if (i + IPOPT_OPTVAL >= optlen)
			return NULL;
		if (q[i + IPOPT_OPTVAL] == IPOPT_EOL ||
		    q[i + IPOPT_OPTVAL] == IPOPT_NOP ||
		    i + IPOPT_OLEN < optlen)
			;
		else
			return NULL;

		switch (q[i + IPOPT_OPTVAL]) {
		case IPOPT_EOL:
			i = optlen;	/* bye */
			break;
		case IPOPT_NOP:
			i++;
			break;
		case IPOPT_LSRR:
		case IPOPT_SSRR:
			if (q[i + IPOPT_OLEN] < 2 + sizeof(struct in_addr) ||
			    optlen - i < q[i + IPOPT_OLEN]) {
				ipseclog((LOG_ERR,
				    "ip_finaldst: invalid IP option "
				    "(code=%02x len=%02x)\n",
				    q[i + IPOPT_OPTVAL], q[i + IPOPT_OLEN]));
				return NULL;
			}
			i += q[i + IPOPT_OLEN] - sizeof(struct in_addr);
			return (struct in_addr *)(void *)(q + i);
		default:
			if (q[i + IPOPT_OLEN] < 2 ||
			    optlen - i < q[i + IPOPT_OLEN]) {
				ipseclog((LOG_ERR,
				    "ip_finaldst: invalid IP option "
				    "(code=%02x len=%02x)\n",
				    q[i + IPOPT_OPTVAL], q[i + IPOPT_OLEN]));
				return NULL;
			}
			i += q[i + IPOPT_OLEN];
			break;
		}
	}
	return NULL;
}
#endif
Commit	Line	Data
b0d623f7	1	/*
316670eb	2	* Copyright (c) 2008-2011 Apple Inc. All rights reserved.
b0d623f7 A	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28
9bccf70c A	29	/* $FreeBSD: src/sys/netinet6/ah_output.c,v 1.1.2.3 2001/07/03 11:01:49 ume Exp $ */
9bccf70c A	30	/* $KAME: ah_output.c,v 1.30 2001/02/21 00:50:53 itojun Exp $ */
1c79356b A	31
	32	/*
	33	* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
	34	* All rights reserved.
	35	*
	36	* Redistribution and use in source and binary forms, with or without
	37	* modification, are permitted provided that the following conditions
	38	* are met:
	39	* 1. Redistributions of source code must retain the above copyright
	40	* notice, this list of conditions and the following disclaimer.
	41	* 2. Redistributions in binary form must reproduce the above copyright
	42	* notice, this list of conditions and the following disclaimer in the
	43	* documentation and/or other materials provided with the distribution.
	44	* 3. Neither the name of the project nor the names of its contributors
	45	* may be used to endorse or promote products derived from this software
	46	* without specific prior written permission.
	47	*
	48	* THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
	49	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	50	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	51	* ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
	52	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	53	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	54	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	55	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	56	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	57	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	58	* SUCH DAMAGE.
	59	*/
	60
	61	/*
	62	* RFC1826/2402 authentication header.
	63	*/
	64
	65	#define _IP_VHL
1c79356b A	66
	67	#include <sys/param.h>
	68	#include <sys/systm.h>
	69	#include <sys/malloc.h>
	70	#include <sys/mbuf.h>
	71	#include <sys/domain.h>
	72	#include <sys/protosw.h>
	73	#include <sys/socket.h>
	74	#include <sys/socketvar.h>
	75	#include <sys/errno.h>
	76	#include <sys/time.h>
	77	#include <sys/kernel.h>
	78	#include <sys/syslog.h>
	79
	80	#include <net/if.h>
	81	#include <net/route.h>
	82
	83	#include <netinet/in.h>
	84
	85	#include <netinet/in_systm.h>
	86	#include <netinet/ip.h>
	87	#include <netinet/in_var.h>
	88
	89	#if INET6
	90	#include <netinet/ip6.h>
	91	#include <netinet6/ip6_var.h>
	92	#include <netinet/icmp6.h>
	93	#endif
	94
	95	#include <netinet6/ipsec.h>
9bccf70c A	96	#if INET6
	97	#include <netinet6/ipsec6.h>
	98	#endif
1c79356b	99	#include <netinet6/ah.h>
9bccf70c A	100	#if INET6
	101	#include <netinet6/ah6.h>
	102	#endif
1c79356b A	103	#include <netkey/key.h>
1c79356b A	104	#include <netkey/keydb.h>
1c79356b A	105
	106	#include <net/net_osdep.h>
	107
9bccf70c	108	#if INET
91447636	109	static struct in_addr ah4_finaldst(struct mbuf );
9bccf70c	110	#endif
1c79356b	111
2d21ac55 A	112	extern lck_mtx_t *sadb_mutex;
2d21ac55 A	113
1c79356b A	114	/*
	115	* compute AH header size.
	116	* transport mode only. for tunnel mode, we should implement
	117	* virtual interface, and control MTU/MSS by the interface MTU.
	118	*/
	119	size_t
	120	ah_hdrsiz(isr)
	121	struct ipsecrequest *isr;
	122	{
1c79356b A	123
	124	/* sanity check */
	125	if (isr == NULL)
	126	panic("ah_hdrsiz: NULL was passed.\n");
	127
	128	if (isr->saidx.proto != IPPROTO_AH)
	129	panic("unsupported mode passed to ah_hdrsiz");
	130
2d21ac55 A	131	#if 0
2d21ac55 A	132	{
1c79356b	133
2d21ac55 A	134	lck_mtx_lock(sadb_mutex);
	135	const struct ah_algorithm *algo;
	136	size_t hdrsiz;
1c79356b	137
2d21ac55 A	138	/%%%%% this needs to change - no sav in ipsecrequest any more /
	139	if (isr->sav == NULL)
	140	goto estimate;
	141	if (isr->sav->state != SADB_SASTATE_MATURE
	142	&& isr->sav->state != SADB_SASTATE_DYING)
	143	goto estimate;
	144
	145	/* we need transport mode AH. */
	146	algo = ah_algorithm_lookup(isr->sav->alg_auth);
	147	if (!algo)
	148	goto estimate;
	149
	150	/*
	151	* XXX
	152	* right now we don't calcurate the padding size. simply
	153	* treat the padding size as constant, for simplicity.
	154	*
	155	* XXX variable size padding support
	156	*/
	157	hdrsiz = (((*algo->sumsiz)(isr->sav) + 3) & ~(4 - 1));
	158	if (isr->sav->flags & SADB_X_EXT_OLD)
	159	hdrsiz += sizeof(struct ah);
	160	else
	161	hdrsiz += sizeof(struct newah);
	162
	163	lck_mtx_unlock(sadb_mutex);
	164	return hdrsiz;
	165	}
1c79356b	166
2d21ac55 A	167	estimate:
2d21ac55 A	168	#endif
1c79356b	169
2d21ac55	170	//lck_mtx_unlock(sadb_mutex);
1c79356b A	171	/* ASSUMING:
	172	* sizeof(struct newah) > sizeof(struct ah).
	173	* 16 = (16 + 3) & ~(4 - 1).
	174	*/
	175	return sizeof(struct newah) + 16;
	176	}
	177
9bccf70c	178	#if INET
1c79356b A	179	/*
	180	* Modify the packet so that it includes the authentication data.
	181	* The mbuf passed must start with IPv4 header.
	182	*
	183	* assumes that the first mbuf contains IPv4 header + option only.
	184	* the function does not modify m.
	185	*/
	186	int
2d21ac55	187	ah4_output(m, sav)
1c79356b	188	struct mbuf *m;
2d21ac55	189	struct secasvar *sav;
1c79356b	190	{
9bccf70c	191	const struct ah_algorithm *algo;
1c79356b A	192	u_int32_t spi;
	193	u_char *ahdrpos;
	194	u_char *ahsumpos = NULL;
	195	size_t hlen = 0; /IP header+option in bytes/
	196	size_t plen = 0; /AH payload size in bytes/
	197	size_t ahlen = 0; /plen + sizeof(ah)/
	198	struct ip *ip;
2d21ac55	199	struct in_addr dst = { 0 };
1c79356b A	200	struct in_addr *finaldst;
	201	int error;
	202
	203	/* sanity checks */
	204	if ((sav->flags & SADB_X_EXT_OLD) == 0 && !sav->replay) {
1c79356b A	205	ip = mtod(m, struct ip *);
	206	ipseclog((LOG_DEBUG, "ah4_output: internal error: "
	207	"sav->replay is null: %x->%x, SPI=%u\n",
	208	(u_int32_t)ntohl(ip->ip_src.s_addr),
	209	(u_int32_t)ntohl(ip->ip_dst.s_addr),
	210	(u_int32_t)ntohl(sav->spi)));
2d21ac55	211	IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
1c79356b A	212	m_freem(m);
	213	return EINVAL;
	214	}
	215
9bccf70c A	216	algo = ah_algorithm_lookup(sav->alg_auth);
	217	if (!algo) {
	218	ipseclog((LOG_ERR, "ah4_output: unsupported algorithm: "
	219	"SPI=%u\n", (u_int32_t)ntohl(sav->spi)));
2d21ac55	220	IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
9bccf70c A	221	m_freem(m);
	222	return EINVAL;
	223	}
1c79356b A	224	spi = sav->spi;
	225
	226	/*
	227	* determine the size to grow.
	228	*/
	229	if (sav->flags & SADB_X_EXT_OLD) {
	230	/* RFC 1826 */
	231	plen = ((algo->sumsiz)(sav) + 3) & ~(4 - 1); /XXX pad to 8byte?*/
	232	ahlen = plen + sizeof(struct ah);
	233	} else {
	234	/* RFC 2402 */
	235	plen = ((algo->sumsiz)(sav) + 3) & ~(4 - 1); /XXX pad to 8byte?*/
	236	ahlen = plen + sizeof(struct newah);
	237	}
	238
	239	/*
	240	* grow the mbuf to accomodate AH.
	241	*/
	242	ip = mtod(m, struct ip *);
	243	#ifdef _IP_VHL
	244	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
	245	#else
	246	hlen = ip->ip_hl << 2;
	247	#endif
	248
	249	if (m->m_len != hlen)
	250	panic("ah4_output: assumption failed (first mbuf length)");
	251	if (M_LEADINGSPACE(m->m_next) < ahlen) {
	252	struct mbuf *n;
	253	MGET(n, M_DONTWAIT, MT_DATA);
	254	if (!n) {
	255	ipseclog((LOG_DEBUG, "ENOBUFS in ah4_output %d\n",
	256	__LINE__));
	257	m_freem(m);
	258	return ENOBUFS;
	259	}
	260	n->m_len = ahlen;
	261	n->m_next = m->m_next;
	262	m->m_next = n;
	263	m->m_pkthdr.len += ahlen;
	264	ahdrpos = mtod(n, u_char *);
	265	} else {
	266	m->m_next->m_len += ahlen;
	267	m->m_next->m_data -= ahlen;
	268	m->m_pkthdr.len += ahlen;
	269	ahdrpos = mtod(m->m_next, u_char *);
	270	}
	271
	272	ip = mtod(m, struct ip ); /just to be sure*/
	273
	274	/*
	275	* initialize AH.
	276	*/
	277	if (sav->flags & SADB_X_EXT_OLD) {
	278	struct ah *ahdr;
	279
316670eb	280	ahdr = (struct ah )(void )ahdrpos;
1c79356b A	281	ahsumpos = (u_char *)(ahdr + 1);
	282	ahdr->ah_len = plen >> 2;
	283	ahdr->ah_nxt = ip->ip_p;
	284	ahdr->ah_reserve = htons(0);
	285	ahdr->ah_spi = spi;
	286	bzero(ahdr + 1, plen);
	287	} else {
	288	struct newah *ahdr;
	289
316670eb	290	ahdr = (struct newah )(void )ahdrpos;
1c79356b A	291	ahsumpos = (u_char *)(ahdr + 1);
	292	ahdr->ah_len = (plen >> 2) + 1; /* plus one for seq# */
	293	ahdr->ah_nxt = ip->ip_p;
	294	ahdr->ah_reserve = htons(0);
	295	ahdr->ah_spi = spi;
	296	if (sav->replay->count == ~0) {
	297	if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
	298	/* XXX Is it noisy ? */
	299	ipseclog((LOG_WARNING,
	300	"replay counter overflowed. %s\n",
	301	ipsec_logsastr(sav)));
2d21ac55	302	IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
1c79356b A	303	m_freem(m);
	304	return EINVAL;
	305	}
	306	}
2d21ac55	307	lck_mtx_lock(sadb_mutex);
1c79356b	308	sav->replay->count++;
2d21ac55	309	lck_mtx_unlock(sadb_mutex);
1c79356b A	310	/*
	311	* XXX sequence number must not be cycled, if the SA is
	312	* installed by IKE daemon.
	313	*/
	314	ahdr->ah_seq = htonl(sav->replay->count);
	315	bzero(ahdr + 1, plen);
	316	}
	317
	318	/*
	319	* modify IPv4 header.
	320	*/
	321	ip->ip_p = IPPROTO_AH;
	322	if (ahlen < (IP_MAXPACKET - ntohs(ip->ip_len)))
	323	ip->ip_len = htons(ntohs(ip->ip_len) + ahlen);
	324	else {
	325	ipseclog((LOG_ERR, "IPv4 AH output: size exceeds limit\n"));
2d21ac55	326	IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
1c79356b A	327	m_freem(m);
	328	return EMSGSIZE;
	329	}
	330
	331	/*
	332	* If there is source routing option, update destination field in
	333	* the IPv4 header to the final destination.
	334	* Note that we do not need to update source routing option itself
	335	* (as done in IPv4 AH processing -- see ip6_output()), since
	336	* source routing option is not part of the ICV computation.
	337	*/
	338	finaldst = ah4_finaldst(m);
	339	if (finaldst) {
	340	dst.s_addr = ip->ip_dst.s_addr;
	341	ip->ip_dst.s_addr = finaldst->s_addr;
	342	}
	343
	344	/*
	345	* calcurate the checksum, based on security association
	346	* and the algorithm specified.
	347	*/
9bccf70c	348	error = ah4_calccksum(m, (caddr_t)ahsumpos, plen, algo, sav);
1c79356b A	349	if (error) {
	350	ipseclog((LOG_ERR,
	351	"error after ah4_calccksum, called from ah4_output"));
9bccf70c	352	m_freem(m);
1c79356b	353	m = NULL;
2d21ac55	354	IPSEC_STAT_INCREMENT(ipsecstat.out_inval);
1c79356b A	355	return error;
	356	}
	357
	358	if (finaldst) {
	359	ip = mtod(m, struct ip ); /just to make sure*/
	360	ip->ip_dst.s_addr = dst.s_addr;
	361	}
2d21ac55	362	lck_mtx_lock(sadb_stat_mutex);
1c79356b A	363	ipsecstat.out_success++;
1c79356b A	364	ipsecstat.out_ahhist[sav->alg_auth]++;
2d21ac55	365	lck_mtx_unlock(sadb_stat_mutex);
1c79356b A	366	key_sa_recordxfer(sav, m);
	367
	368	return 0;
	369	}
9bccf70c	370	#endif
1c79356b A	371
	372	/* Calculate AH length */
	373	int
	374	ah_hdrlen(sav)
	375	struct secasvar *sav;
	376	{
9bccf70c	377	const struct ah_algorithm *algo;
1c79356b A	378	int plen, ahlen;
1c79356b A	379
9bccf70c A	380	algo = ah_algorithm_lookup(sav->alg_auth);
	381	if (!algo)
	382	return 0;
1c79356b A	383	if (sav->flags & SADB_X_EXT_OLD) {
	384	/* RFC 1826 */
	385	plen = ((algo->sumsiz)(sav) + 3) & ~(4 - 1); /XXX pad to 8byte?*/
	386	ahlen = plen + sizeof(struct ah);
	387	} else {
	388	/* RFC 2402 */
	389	plen = ((algo->sumsiz)(sav) + 3) & ~(4 - 1); /XXX pad to 8byte?*/
	390	ahlen = plen + sizeof(struct newah);
	391	}
	392
	393	return(ahlen);
	394	}
	395
	396	#if INET6
	397	/*
	398	* Fill in the Authentication Header and calculate checksum.
	399	*/
	400	int
2d21ac55	401	ah6_output(m, nexthdrp, md, sav)
1c79356b A	402	struct mbuf *m;
	403	u_char *nexthdrp;
	404	struct mbuf *md;
2d21ac55	405	struct secasvar *sav;
1c79356b A	406	{
	407	struct mbuf *mprev;
	408	struct mbuf *mah;
9bccf70c	409	const struct ah_algorithm *algo;
1c79356b A	410	u_int32_t spi;
	411	u_char *ahsumpos = NULL;
	412	size_t plen; /AH payload size in bytes/
	413	int error = 0;
	414	int ahlen;
	415	struct ip6_hdr *ip6;
	416
	417	if (m->m_len < sizeof(struct ip6_hdr)) {
	418	ipseclog((LOG_DEBUG, "ah6_output: first mbuf too short\n"));
	419	m_freem(m);
	420	return EINVAL;
	421	}
	422
	423	ahlen = ah_hdrlen(sav);
	424	if (ahlen == 0)
	425	return 0;
	426
	427	for (mprev = m; mprev && mprev->m_next != md; mprev = mprev->m_next)
	428	;
	429	if (!mprev \|\| mprev->m_next != md) {
	430	ipseclog((LOG_DEBUG, "ah6_output: md is not in chain\n"));
	431	m_freem(m);
	432	return EINVAL;
	433	}
	434
	435	MGET(mah, M_DONTWAIT, MT_DATA);
	436	if (!mah) {
	437	m_freem(m);
	438	return ENOBUFS;
	439	}
	440	if (ahlen > MLEN) {
	441	MCLGET(mah, M_DONTWAIT);
	442	if ((mah->m_flags & M_EXT) == 0) {
	443	m_free(mah);
	444	m_freem(m);
	445	return ENOBUFS;
	446	}
	447	}
	448	mah->m_len = ahlen;
	449	mah->m_next = md;
	450	mprev->m_next = mah;
	451	m->m_pkthdr.len += ahlen;
	452
	453	/* fix plen */
	454	if (m->m_pkthdr.len - sizeof(struct ip6_hdr) > IPV6_MAXPACKET) {
	455	ipseclog((LOG_ERR,
	456	"ip6_output: AH with IPv6 jumbogram is not supported\n"));
	457	m_freem(m);
	458	return EINVAL;
	459	}
	460	ip6 = mtod(m, struct ip6_hdr *);
	461	ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
	462
	463	if ((sav->flags & SADB_X_EXT_OLD) == 0 && !sav->replay) {
	464	ipseclog((LOG_DEBUG, "ah6_output: internal error: "
2d21ac55 A	465	"sav->replay is null: SPI=%u\n",
	466	(u_int32_t)ntohl(sav->spi)));
	467	IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
1c79356b A	468	m_freem(m);
	469	return EINVAL;
	470	}
	471
9bccf70c A	472	algo = ah_algorithm_lookup(sav->alg_auth);
	473	if (!algo) {
	474	ipseclog((LOG_ERR, "ah6_output: unsupported algorithm: "
	475	"SPI=%u\n", (u_int32_t)ntohl(sav->spi)));
2d21ac55	476	IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
9bccf70c A	477	m_freem(m);
	478	return EINVAL;
	479	}
1c79356b A	480	spi = sav->spi;
	481
	482	/*
	483	* initialize AH.
	484	*/
	485	if (sav->flags & SADB_X_EXT_OLD) {
	486	struct ah ahdr = mtod(mah, struct ah );
	487
	488	plen = mah->m_len - sizeof(struct ah);
	489	ahsumpos = (u_char *)(ahdr + 1);
	490	ahdr->ah_nxt = *nexthdrp;
	491	*nexthdrp = IPPROTO_AH;
	492	ahdr->ah_len = plen >> 2;
	493	ahdr->ah_reserve = htons(0);
	494	ahdr->ah_spi = spi;
	495	bzero(ahdr + 1, plen);
	496	} else {
	497	struct newah ahdr = mtod(mah, struct newah );
	498
	499	plen = mah->m_len - sizeof(struct newah);
	500	ahsumpos = (u_char *)(ahdr + 1);
	501	ahdr->ah_nxt = *nexthdrp;
	502	*nexthdrp = IPPROTO_AH;
	503	ahdr->ah_len = (plen >> 2) + 1; /* plus one for seq# */
	504	ahdr->ah_reserve = htons(0);
	505	ahdr->ah_spi = spi;
	506	if (sav->replay->count == ~0) {
	507	if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0) {
	508	/* XXX Is it noisy ? */
	509	ipseclog((LOG_WARNING,
2d21ac55	510	"replay counter overflowed. %s\n",
1c79356b	511	ipsec_logsastr(sav)));
2d21ac55	512	IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
1c79356b A	513	m_freem(m);
	514	return EINVAL;
	515	}
	516	}
2d21ac55	517	lck_mtx_lock(sadb_mutex);
1c79356b	518	sav->replay->count++;
2d21ac55	519	lck_mtx_unlock(sadb_mutex);
1c79356b A	520	/*
	521	* XXX sequence number must not be cycled, if the SA is
	522	* installed by IKE daemon.
	523	*/
	524	ahdr->ah_seq = htonl(sav->replay->count);
	525	bzero(ahdr + 1, plen);
	526	}
	527
	528	/*
	529	* calcurate the checksum, based on security association
	530	* and the algorithm specified.
	531	*/
9bccf70c	532	error = ah6_calccksum(m, (caddr_t)ahsumpos, plen, algo, sav);
1c79356b	533	if (error) {
2d21ac55	534	IPSEC_STAT_INCREMENT(ipsec6stat.out_inval);
1c79356b A	535	m_freem(m);
1c79356b A	536	} else {
2d21ac55	537	IPSEC_STAT_INCREMENT(ipsec6stat.out_success);
1c79356b A	538	key_sa_recordxfer(sav, m);
1c79356b A	539	}
2d21ac55	540	IPSEC_STAT_INCREMENT(ipsec6stat.out_ahhist[sav->alg_auth]);
1c79356b A	541
	542	return(error);
	543	}
	544	#endif
	545
9bccf70c	546	#if INET
1c79356b A	547	/*
	548	* Find the final destination if there is loose/strict source routing option.
	549	* Returns NULL if there's no source routing options.
	550	* Returns NULL on errors too.
	551	* Note that this function will return a pointer INTO the given parameter,
	552	* struct mbuf *m.
	553	* The mbuf must be pulled up toward, at least, ip option part.
	554	*/
	555	static struct in_addr *
	556	ah4_finaldst(m)
	557	struct mbuf *m;
	558	{
	559	struct ip *ip;
	560	int optlen;
	561	u_char *q;
	562	int i;
	563	int hlen;
	564
	565	if (!m)
	566	panic("ah4_finaldst: m == NULL");
	567	ip = mtod(m, struct ip *);
	568	#ifdef _IP_VHL
	569	hlen = IP_VHL_HL(ip->ip_vhl) << 2;
	570	#else
	571	hlen = ip->ip_hl << 2;
	572	#endif
	573
	574	if (m->m_len < hlen) {
	575	ipseclog((LOG_DEBUG,
	576	"ah4_finaldst: parameter mbuf wrong (not pulled up)\n"));
	577	return NULL;
	578	}
	579
	580	if (hlen == sizeof(struct ip))
	581	return NULL;
	582
	583	optlen = hlen - sizeof(struct ip);
	584	if (optlen < 0) {
	585	ipseclog((LOG_DEBUG, "ah4_finaldst: wrong optlen %d\n",
	586	optlen));
	587	return NULL;
	588	}
	589
	590	q = (u_char *)(ip + 1);
	591	i = 0;
	592	while (i < optlen) {
9bccf70c A	593	if (i + IPOPT_OPTVAL >= optlen)
	594	return NULL;
	595	if (q[i + IPOPT_OPTVAL] == IPOPT_EOL \|\|
	596	q[i + IPOPT_OPTVAL] == IPOPT_NOP \|\|
	597	i + IPOPT_OLEN < optlen)
	598	;
	599	else
	600	return NULL;
	601
1c79356b A	602	switch (q[i + IPOPT_OPTVAL]) {
	603	case IPOPT_EOL:
	604	i = optlen; /* bye */
	605	break;
	606	case IPOPT_NOP:
	607	i++;
	608	break;
	609	case IPOPT_LSRR:
	610	case IPOPT_SSRR:
9bccf70c A	611	if (q[i + IPOPT_OLEN] < 2 + sizeof(struct in_addr) \|\|
9bccf70c A	612	optlen - i < q[i + IPOPT_OLEN]) {
1c79356b A	613	ipseclog((LOG_ERR,
	614	"ip_finaldst: invalid IP option "
	615	"(code=%02x len=%02x)\n",
	616	q[i + IPOPT_OPTVAL], q[i + IPOPT_OLEN]));
	617	return NULL;
	618	}
	619	i += q[i + IPOPT_OLEN] - sizeof(struct in_addr);
316670eb	620	return (struct in_addr )(void )(q + i);
1c79356b	621	default:
9bccf70c A	622	if (q[i + IPOPT_OLEN] < 2 \|\|
9bccf70c A	623	optlen - i < q[i + IPOPT_OLEN]) {
1c79356b A	624	ipseclog((LOG_ERR,
	625	"ip_finaldst: invalid IP option "
	626	"(code=%02x len=%02x)\n",
	627	q[i + IPOPT_OPTVAL], q[i + IPOPT_OLEN]));
	628	return NULL;
	629	}
	630	i += q[i + IPOPT_OLEN];
	631	break;
	632	}
	633	}
	634	return NULL;
	635	}
9bccf70c	636	#endif