NetBSD/sys/netinet6/ah_input.c

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/* $NetBSD: ah_input.c,v 1.37 2002/09/11 03:45:44 itojun Exp $ */
/* $KAME: ah_input.c,v 1.64 2001/09/04 08:43:19 itojun Exp $ */
1999-07-04 01:24:45 +04:00
/*
* 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.
*/
2001-11-13 03:56:55 +03:00
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ah_input.c,v 1.37 2002/09/11 03:45:44 itojun Exp $");
2001-11-13 03:56:55 +03:00
#include "opt_inet.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/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/route.h>
#include <net/netisr.h>
#include <machine/cpu.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/ip_ecn.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip6.h>
2000-08-16 01:43:57 +04:00
#ifdef INET6
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6protosw.h>
#endif
#include <netinet6/ipsec.h>
#include <netinet6/ah.h>
#include <netkey/key.h>
#include <netkey/keydb.h>
#include <netkey/key_debug.h>
#include <machine/stdarg.h>
#include <net/net_osdep.h>
/*#define IPLEN_FLIPPED*/
2000-03-26 23:11:04 +04:00
#ifdef INET
void
#if __STDC__
ah4_input(struct mbuf *m, ...)
#else
ah4_input(m, va_alist)
struct mbuf *m;
va_dcl
#endif
{
struct ip *ip;
struct ah *ah;
u_int32_t spi;
const struct ah_algorithm *algo;
size_t siz;
size_t siz1;
u_int8_t cksum[AH_MAXSUMSIZE];
struct secasvar *sav = NULL;
u_int16_t nxt;
size_t hlen;
int s;
int off, proto;
va_list ap;
size_t stripsiz = 0;
va_start(ap, m);
off = va_arg(ap, int);
proto = va_arg(ap, int);
va_end(ap);
#ifndef PULLDOWN_TEST
if (m->m_len < off + sizeof(struct newah)) {
m = m_pullup(m, off + sizeof(struct newah));
if (!m) {
ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;"
"dropping the packet for simplicity\n"));
ipsecstat.in_inval++;
goto fail;
}
}
ip = mtod(m, struct ip *);
ah = (struct ah *)(((caddr_t)ip) + off);
#else
ip = mtod(m, struct ip *);
IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah));
if (ah == NULL) {
ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup;"
"dropping the packet for simplicity\n"));
ipsecstat.in_inval++;
goto fail;
}
#endif
nxt = ah->ah_nxt;
#ifdef _IP_VHL
hlen = IP_VHL_HL(ip->ip_vhl) << 2;
#else
hlen = ip->ip_hl << 2;
#endif
/* find the sassoc. */
spi = ah->ah_spi;
if ((sav = key_allocsa(AF_INET,
(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
IPPROTO_AH, spi)) == 0) {
ipseclog((LOG_WARNING,
"IPv4 AH input: no key association found for spi %u\n",
(u_int32_t)ntohl(spi)));
ipsecstat.in_nosa++;
goto fail;
}
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah4_input called to allocate SA:%p\n", sav));
if (sav->state != SADB_SASTATE_MATURE
&& sav->state != SADB_SASTATE_DYING) {
ipseclog((LOG_DEBUG,
"IPv4 AH input: non-mature/dying SA found for spi %u\n",
(u_int32_t)ntohl(spi)));
ipsecstat.in_badspi++;
goto fail;
}
algo = ah_algorithm_lookup(sav->alg_auth);
if (!algo) {
ipseclog((LOG_DEBUG, "IPv4 AH input: "
"unsupported authentication algorithm for spi %u\n",
(u_int32_t)ntohl(spi)));
ipsecstat.in_badspi++;
goto fail;
}
siz = (*algo->sumsiz)(sav);
siz1 = ((siz + 3) & ~(4 - 1));
/*
* sanity checks for header, 1.
*/
{
int sizoff;
sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
/*
* Here, we do not do "siz1 == siz". This is because the way
* RFC240[34] section 2 is written. They do not require truncation
* to 96 bits.
* For example, Microsoft IPsec stack attaches 160 bits of
* authentication data for both hmac-md5 and hmac-sha1. For hmac-sha1,
* 32 bits of padding is attached.
*
* There are two downsides to this specification.
* They have no real harm, however, they leave us fuzzy feeling.
* - if we attach more than 96 bits of authentication data onto AH,
* we will never notice about possible modification by rogue
* intermediate nodes.
* Since extra bits in AH checksum is never used, this constitutes
* no real issue, however, it is wacky.
* - even if the peer attaches big authentication data, we will never
* notice the difference, since longer authentication data will just
* work.
*
* We may need some clarification in the spec.
*/
if (siz1 < siz) {
ipseclog((LOG_NOTICE, "sum length too short in IPv4 AH input "
"(%lu, should be at least %lu): %s\n",
(u_long)siz1, (u_long)siz,
ipsec4_logpacketstr(ip, spi)));
ipsecstat.in_inval++;
goto fail;
}
if ((ah->ah_len << 2) - sizoff != siz1) {
ipseclog((LOG_NOTICE, "sum length mismatch in IPv4 AH input "
"(%d should be %lu): %s\n",
(ah->ah_len << 2) - sizoff, (u_long)siz1,
ipsec4_logpacketstr(ip, spi)));
ipsecstat.in_inval++;
goto fail;
}
if (siz1 > sizeof(cksum)) {
ipseclog((LOG_NOTICE, "sum length too large: %s\n",
ipsec4_logpacketstr(ip, spi)));
ipsecstat.in_inval++;
goto fail;
}
#ifndef PULLDOWN_TEST
if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) {
m = m_pullup(m, off + sizeof(struct ah) + sizoff + siz1);
if (!m) {
ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n"));
ipsecstat.in_inval++;
goto fail;
}
ip = mtod(m, struct ip *);
ah = (struct ah *)(((caddr_t)ip) + off);
}
#else
IP6_EXTHDR_GET(ah, struct ah *, m, off,
sizeof(struct ah) + sizoff + siz1);
if (ah == NULL) {
ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n"));
ipsecstat.in_inval++;
goto fail;
}
#endif
}
/*
* check for sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav))
; /* okey */
else {
ipsecstat.in_ahreplay++;
ipseclog((LOG_WARNING,
"replay packet in IPv4 AH input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
goto fail;
}
}
/*
* alright, it seems sane. now we are going to check the
* cryptographic checksum.
*/
2002-06-09 18:43:10 +04:00
{
#if 0
/*
* some of IP header fields are flipped to the host endian.
* convert them back to network endian. VERY stupid.
*/
ip->ip_len = htons(ip->ip_len);
ip->ip_off = htons(ip->ip_off);
#endif
if (ah4_calccksum(m, cksum, siz1, algo, sav)) {
ipsecstat.in_inval++;
goto fail;
}
ipsecstat.in_ahhist[sav->alg_auth]++;
#if 0
/*
* flip them back.
*/
ip->ip_len = ntohs(ip->ip_len);
ip->ip_off = ntohs(ip->ip_off);
#endif
}
{
caddr_t sumpos = NULL;
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1826 */
sumpos = (caddr_t)(ah + 1);
} else {
/* RFC 2402 */
sumpos = (caddr_t)(((struct newah *)ah) + 1);
}
if (bcmp(sumpos, cksum, siz) != 0) {
ipseclog((LOG_WARNING,
"checksum mismatch in IPv4 AH input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
ipsecstat.in_ahauthfail++;
goto fail;
}
}
m->m_flags |= M_AUTHIPHDR;
m->m_flags |= M_AUTHIPDGM;
#if 0
/*
* looks okey, but we need more sanity check.
* XXX should elaborate.
*/
if (ah->ah_nxt == IPPROTO_IPIP || ah->ah_nxt == IPPROTO_IP) {
struct ip *nip;
size_t sizoff;
sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
if (m->m_len < off + sizeof(struct ah) + sizoff + siz1 + hlen) {
m = m_pullup(m, off + sizeof(struct ah)
+ sizoff + siz1 + hlen);
if (!m) {
ipseclog((LOG_DEBUG,
"IPv4 AH input: can't pullup\n"));
ipsecstat.in_inval++;
goto fail;
}
}
nip = (struct ip *)((u_char *)(ah + 1) + sizoff + siz1);
if (nip->ip_src.s_addr != ip->ip_src.s_addr
|| nip->ip_dst.s_addr != ip->ip_dst.s_addr) {
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
}
}
#ifdef INET6
else if (ah->ah_nxt == IPPROTO_IPV6) {
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
}
#endif /* INET6 */
#endif /* 0 */
if (m->m_flags & M_AUTHIPHDR
&& m->m_flags & M_AUTHIPDGM) {
#if 0
ipseclog((LOG_DEBUG,
"IPv4 AH input: authentication succeess\n"));
#endif
ipsecstat.in_ahauthsucc++;
} else {
ipseclog((LOG_WARNING,
"authentication failed in IPv4 AH input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
ipsecstat.in_ahauthfail++;
goto fail;
}
/*
* update sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) {
ipsecstat.in_ahreplay++;
goto fail;
}
}
/* was it transmitted over the IPsec tunnel SA? */
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1826 */
stripsiz = sizeof(struct ah) + siz1;
} else {
/* RFC 2402 */
stripsiz = sizeof(struct newah) + siz1;
}
if (ipsec4_tunnel_validate(ip, nxt, sav)) {
/*
* strip off all the headers that precedes AH.
* IP xx AH IP' payload -> IP' payload
*
* XXX more sanity checks
* XXX relationship with gif?
*/
u_int8_t tos;
tos = ip->ip_tos;
m_adj(m, off + stripsiz);
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (!m) {
ipsecstat.in_inval++;
goto fail;
}
}
ip = mtod(m, struct ip *);
/* ECN consideration. */
ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos);
if (!key_checktunnelsanity(sav, AF_INET,
(caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst)) {
ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch "
"in IPv4 AH input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
ipsecstat.in_inval++;
goto fail;
}
#if 1
/*
* Should the inner packet be considered authentic?
* My current answer is: NO.
*
* host1 -- gw1 === gw2 -- host2
* In this case, gw2 can trust the authenticity of the
* outer packet, but NOT inner. Packet may be altered
* between host1 and gw1.
*
* host1 -- gw1 === host2
* This case falls into the same scenario as above.
*
* host1 === host2
* This case is the only case when we may be able to leave
* M_AUTHIPHDR and M_AUTHIPDGM set.
* However, if host1 is wrongly configured, and allows
* attacker to inject some packet with src=host1 and
* dst=host2, you are in risk.
*/
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
#endif
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 ||
ipsec_addhist(m, IPPROTO_IPV4, 0) != 0) {
ipsecstat.in_nomem++;
goto fail;
}
s = splnet();
if (IF_QFULL(&ipintrq)) {
ipsecstat.in_inval++;
splx(s);
goto fail;
}
IF_ENQUEUE(&ipintrq, m);
m = NULL;
schednetisr(NETISR_IP); /* can be skipped but to make sure */
splx(s);
nxt = IPPROTO_DONE;
} else {
/*
* strip off AH.
*/
ip = mtod(m, struct ip *);
#ifndef PULLDOWN_TEST
/*
* We do deep-copy since KAME requires that
* the packet is placed in a single external mbuf.
*/
ovbcopy((caddr_t)ip, (caddr_t)(((u_char *)ip) + stripsiz), off);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
#else
/*
* even in m_pulldown case, we need to strip off AH so that
* we can compute checksum for multiple AH correctly.
*/
if (m->m_len >= stripsiz + off) {
ovbcopy((caddr_t)ip, ((caddr_t)ip) + stripsiz, off);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
} else {
/*
* this comes with no copy if the boundary is on
* cluster
*/
struct mbuf *n;
n = m_split(m, off, M_DONTWAIT);
if (n == NULL) {
/* m is retained by m_split */
goto fail;
}
m_adj(n, stripsiz);
m_cat(m, n);
/* m_cat does not update m_pkthdr.len */
m->m_pkthdr.len += n->m_pkthdr.len;
}
#endif
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (m == NULL) {
ipsecstat.in_inval++;
goto fail;
}
}
ip = mtod(m, struct ip *);
#ifdef IPLEN_FLIPPED
ip->ip_len = ip->ip_len - stripsiz;
#else
ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
#endif
ip->ip_p = nxt;
/* forget about IP hdr checksum, the check has already been passed */
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) {
ipsecstat.in_nomem++;
goto fail;
}
if (nxt != IPPROTO_DONE) {
if ((inetsw[ip_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
ipsec4_in_reject(m, NULL)) {
ipsecstat.in_polvio++;
goto fail;
}
(*inetsw[ip_protox[nxt]].pr_input)(m, off, nxt);
} else
m_freem(m);
m = NULL;
}
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah4_input call free SA:%p\n", sav));
key_freesav(sav);
}
ipsecstat.in_success++;
return;
fail:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah4_input call free SA:%p\n", sav));
key_freesav(sav);
}
if (m)
m_freem(m);
return;
}
/* assumes that ip header and ah header are contiguous on mbuf */
void *
ah4_ctlinput(cmd, sa, v)
int cmd;
struct sockaddr *sa;
void *v;
{
struct ip *ip = v;
struct ah *ah;
struct icmp *icp;
struct secasvar *sav;
if (sa->sa_family != AF_INET ||
sa->sa_len != sizeof(struct sockaddr_in))
return NULL;
if ((unsigned)cmd >= PRC_NCMDS)
return NULL;
if (cmd == PRC_MSGSIZE && ip_mtudisc && ip && ip->ip_v == 4) {
/*
* Check to see if we have a valid SA corresponding to
* the address in the ICMP message payload.
*/
ah = (struct ah *)((caddr_t)ip + (ip->ip_hl << 2));
if ((sav = key_allocsa(AF_INET,
(caddr_t) &ip->ip_src,
(caddr_t) &ip->ip_dst,
IPPROTO_AH, ah->ah_spi)) == NULL)
return NULL;
if (sav->state != SADB_SASTATE_MATURE &&
sav->state != SADB_SASTATE_DYING) {
key_freesav(sav);
return NULL;
}
/* XXX Further validation? */
key_freesav(sav);
/*
* Now that we've validated that we are actually communicating
* with the host indicated in the ICMP message, locate the
* ICMP header, recalculate the new MTU, and create the
* corresponding routing entry.
*/
icp = (struct icmp *)((caddr_t)ip -
offsetof(struct icmp, icmp_ip));
icmp_mtudisc(icp, ip->ip_dst);
return NULL;
}
return NULL;
}
#endif /* INET */
#ifdef INET6
int
ah6_input(mp, offp, proto)
struct mbuf **mp;
int *offp, proto;
{
struct mbuf *m = *mp;
int off = *offp;
struct ip6_hdr *ip6;
struct ah *ah;
u_int32_t spi;
const struct ah_algorithm *algo;
size_t siz;
size_t siz1;
u_int8_t cksum[AH_MAXSUMSIZE];
struct secasvar *sav = NULL;
u_int16_t nxt;
int s;
size_t stripsiz = 0;
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), IPPROTO_DONE);
ah = (struct ah *)(mtod(m, caddr_t) + off);
#else
IP6_EXTHDR_GET(ah, struct ah *, m, off, sizeof(struct newah));
if (ah == NULL) {
ipseclog((LOG_DEBUG, "IPv6 AH input: can't pullup\n"));
ipsec6stat.in_inval++;
return IPPROTO_DONE;
}
#endif
ip6 = mtod(m, struct ip6_hdr *);
nxt = ah->ah_nxt;
2001-12-21 11:54:52 +03:00
/* find the sassoc. */
spi = ah->ah_spi;
if (ntohs(ip6->ip6_plen) == 0) {
ipseclog((LOG_ERR, "IPv6 AH input: "
"AH with IPv6 jumbogram is not supported.\n"));
ipsec6stat.in_inval++;
goto fail;
}
if ((sav = key_allocsa(AF_INET6,
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
IPPROTO_AH, spi)) == 0) {
ipseclog((LOG_WARNING,
"IPv6 AH input: no key association found for spi %u\n",
(u_int32_t)ntohl(spi)));
ipsec6stat.in_nosa++;
goto fail;
}
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah6_input called to allocate SA:%p\n", sav));
if (sav->state != SADB_SASTATE_MATURE
&& sav->state != SADB_SASTATE_DYING) {
ipseclog((LOG_DEBUG,
"IPv6 AH input: non-mature/dying SA found for spi %u; ",
(u_int32_t)ntohl(spi)));
ipsec6stat.in_badspi++;
goto fail;
}
algo = ah_algorithm_lookup(sav->alg_auth);
if (!algo) {
ipseclog((LOG_DEBUG, "IPv6 AH input: "
"unsupported authentication algorithm for spi %u\n",
(u_int32_t)ntohl(spi)));
ipsec6stat.in_badspi++;
goto fail;
}
siz = (*algo->sumsiz)(sav);
siz1 = ((siz + 3) & ~(4 - 1));
/*
* sanity checks for header, 1.
*/
{
int sizoff;
sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
/*
* Here, we do not do "siz1 == siz". See ah4_input() for complete
* description.
*/
if (siz1 < siz) {
ipseclog((LOG_NOTICE, "sum length too short in IPv6 AH input "
"(%lu, should be at least %lu): %s\n",
(u_long)siz1, (u_long)siz,
ipsec6_logpacketstr(ip6, spi)));
ipsec6stat.in_inval++;
goto fail;
}
if ((ah->ah_len << 2) - sizoff != siz1) {
ipseclog((LOG_NOTICE, "sum length mismatch in IPv6 AH input "
"(%d should be %lu): %s\n",
(ah->ah_len << 2) - sizoff, (u_long)siz1,
ipsec6_logpacketstr(ip6, spi)));
ipsec6stat.in_inval++;
goto fail;
}
if (siz1 > sizeof(cksum)) {
ipseclog((LOG_NOTICE, "sum length too large: %s\n",
ipsec6_logpacketstr(ip6, spi)));
ipsec6stat.in_inval++;
goto fail;
}
#ifndef PULLDOWN_TEST
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1, IPPROTO_DONE);
#else
IP6_EXTHDR_GET(ah, struct ah *, m, off,
sizeof(struct ah) + sizoff + siz1);
if (ah == NULL) {
ipseclog((LOG_NOTICE, "couldn't pullup gather IPv6 AH checksum part"));
ipsec6stat.in_inval++;
m = NULL;
goto fail;
}
#endif
}
/*
* check for sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav))
; /* okey */
else {
ipsec6stat.in_ahreplay++;
ipseclog((LOG_WARNING,
"replay packet in IPv6 AH input: %s %s\n",
ipsec6_logpacketstr(ip6, spi),
ipsec_logsastr(sav)));
goto fail;
}
}
/*
* alright, it seems sane. now we are going to check the
* cryptographic checksum.
*/
2002-06-09 18:43:10 +04:00
if (ah6_calccksum(m, cksum, siz1, algo, sav)) {
ipsec6stat.in_inval++;
goto fail;
}
ipsec6stat.in_ahhist[sav->alg_auth]++;
{
caddr_t sumpos = NULL;
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1826 */
sumpos = (caddr_t)(ah + 1);
} else {
/* RFC 2402 */
sumpos = (caddr_t)(((struct newah *)ah) + 1);
}
if (bcmp(sumpos, cksum, siz) != 0) {
ipseclog((LOG_WARNING,
"checksum mismatch in IPv6 AH input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
ipsec6stat.in_ahauthfail++;
goto fail;
}
}
m->m_flags |= M_AUTHIPHDR;
m->m_flags |= M_AUTHIPDGM;
#if 0
/*
* looks okey, but we need more sanity check.
* XXX should elaborate.
*/
if (ah->ah_nxt == IPPROTO_IPV6) {
struct ip6_hdr *nip6;
size_t sizoff;
sizoff = (sav->flags & SADB_X_EXT_OLD) ? 0 : 4;
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah) + sizoff + siz1
+ sizeof(struct ip6_hdr), IPPROTO_DONE);
nip6 = (struct ip6_hdr *)((u_char *)(ah + 1) + sizoff + siz1);
if (!IN6_ARE_ADDR_EQUAL(&nip6->ip6_src, &ip6->ip6_src)
|| !IN6_ARE_ADDR_EQUAL(&nip6->ip6_dst, &ip6->ip6_dst)) {
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
}
} else if (ah->ah_nxt == IPPROTO_IPIP) {
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
} else if (ah->ah_nxt == IPPROTO_IP) {
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
}
#endif
if (m->m_flags & M_AUTHIPHDR
&& m->m_flags & M_AUTHIPDGM) {
#if 0
ipseclog((LOG_DEBUG,
"IPv6 AH input: authentication succeess\n"));
#endif
ipsec6stat.in_ahauthsucc++;
} else {
ipseclog((LOG_WARNING,
"authentication failed in IPv6 AH input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
ipsec6stat.in_ahauthfail++;
goto fail;
}
/*
* update sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay) {
if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav)) {
ipsec6stat.in_ahreplay++;
goto fail;
}
}
/* was it transmitted over the IPsec tunnel SA? */
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1826 */
stripsiz = sizeof(struct ah) + siz1;
} else {
/* RFC 2402 */
stripsiz = sizeof(struct newah) + siz1;
}
if (ipsec6_tunnel_validate(ip6, nxt, sav)) {
/*
* strip off all the headers that precedes AH.
* IP6 xx AH IP6' payload -> IP6' payload
*
* XXX more sanity checks
* XXX relationship with gif?
*/
u_int32_t flowinfo; /* net endian */
flowinfo = ip6->ip6_flow;
m_adj(m, off + stripsiz);
if (m->m_len < sizeof(*ip6)) {
/*
* m_pullup is prohibited in KAME IPv6 input processing
* but there's no other way!
*/
m = m_pullup(m, sizeof(*ip6));
if (!m) {
ipsec6stat.in_inval++;
goto fail;
}
}
ip6 = mtod(m, struct ip6_hdr *);
/* ECN consideration. */
ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow);
if (!key_checktunnelsanity(sav, AF_INET6,
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst)) {
ipseclog((LOG_NOTICE, "ipsec tunnel address mismatch "
"in IPv6 AH input: %s %s\n",
ipsec6_logpacketstr(ip6, spi),
ipsec_logsastr(sav)));
ipsec6stat.in_inval++;
goto fail;
}
#if 1
/*
* should the inner packet be considered authentic?
* see comment in ah4_input().
*/
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
#endif
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_AH, spi) != 0 ||
ipsec_addhist(m, IPPROTO_IPV6, 0) != 0) {
ipsec6stat.in_nomem++;
goto fail;
}
s = splnet();
if (IF_QFULL(&ip6intrq)) {
ipsec6stat.in_inval++;
splx(s);
goto fail;
}
IF_ENQUEUE(&ip6intrq, m);
m = NULL;
schednetisr(NETISR_IPV6); /* can be skipped but to make sure */
splx(s);
nxt = IPPROTO_DONE;
} else {
/*
* strip off AH.
*/
u_int8_t *prvnxtp;
/*
* Copy the value of the next header field of AH to the
* next header field of the previous header.
* This is necessary because AH will be stripped off below.
*/
prvnxtp = ip6_get_prevhdr(m, off); /* XXX */
*prvnxtp = nxt;
ip6 = mtod(m, struct ip6_hdr *);
#ifndef PULLDOWN_TEST
/*
* We do deep-copy since KAME requires that
* the packet is placed in a single mbuf.
*/
ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
#else
/*
* even in m_pulldown case, we need to strip off AH so that
* we can compute checksum for multiple AH correctly.
*/
if (m->m_len >= stripsiz + off) {
ovbcopy((caddr_t)ip6, ((caddr_t)ip6) + stripsiz, off);
m->m_data += stripsiz;
m->m_len -= stripsiz;
m->m_pkthdr.len -= stripsiz;
} else {
/*
* this comes with no copy if the boundary is on
* cluster
*/
struct mbuf *n;
n = m_split(m, off, M_DONTWAIT);
if (n == NULL) {
/* m is retained by m_split */
goto fail;
}
m_adj(n, stripsiz);
m_cat(m, n);
/* m_cat does not update m_pkthdr.len */
m->m_pkthdr.len += n->m_pkthdr.len;
}
#endif
ip6 = mtod(m, struct ip6_hdr *);
/* XXX jumbogram */
ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - stripsiz);
key_sa_recordxfer(sav, m);
if (ipsec_addhist(m, IPPROTO_AH, spi) != 0) {
ipsec6stat.in_nomem++;
goto fail;
}
}
*offp = off;
*mp = m;
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah6_input call free SA:%p\n", sav));
key_freesav(sav);
}
ipsec6stat.in_success++;
return nxt;
fail:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah6_input call free SA:%p\n", sav));
key_freesav(sav);
}
if (m)
m_freem(m);
return IPPROTO_DONE;
}
void
ah6_ctlinput(cmd, sa, d)
int cmd;
struct sockaddr *sa;
void *d;
{
const struct newah *ahp;
struct newah ah;
struct secasvar *sav;
struct ip6_hdr *ip6;
struct mbuf *m;
struct ip6ctlparam *ip6cp = NULL;
int off;
struct sockaddr_in6 *sa6_src, *sa6_dst;
if (sa->sa_family != AF_INET6 ||
sa->sa_len != sizeof(struct sockaddr_in6))
return;
if ((unsigned)cmd >= PRC_NCMDS)
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;
} else {
m = NULL;
ip6 = NULL;
}
if (ip6) {
/*
* XXX: We assume that when ip6 is non NULL,
* M and OFF are valid.
*/
/* check if we can safely examine src and dst ports */
if (m->m_pkthdr.len < off + sizeof(ah))
return;
if (m->m_len < off + sizeof(ah)) {
/*
* this should be rare case,
* so we compromise on this copy...
*/
m_copydata(m, off, sizeof(ah), (caddr_t)&ah);
ahp = &ah;
} else
ahp = (struct newah *)(mtod(m, caddr_t) + off);
if (cmd == PRC_MSGSIZE) {
int valid = 0;
/*
* Check to see if we have a valid SA corresponding to
* the address in the ICMP message payload.
*/
sa6_src = ip6cp->ip6c_src;
sa6_dst = (struct sockaddr_in6 *)sa;
sav = key_allocsa(AF_INET6,
(caddr_t)&sa6_src->sin6_addr,
(caddr_t)&sa6_dst->sin6_addr,
IPPROTO_AH, ahp->ah_spi);
if (sav) {
if (sav->state == SADB_SASTATE_MATURE ||
sav->state == SADB_SASTATE_DYING)
valid++;
key_freesav(sav);
}
/* XXX Further validation? */
/*
* Depending on the value of "valid" and routing table
* size (mtudisc_{hi,lo}wat), we will:
* - recalcurate the new MTU and create the
* corresponding routing entry, or
* - ignore the MTU change notification.
*/
icmp6_mtudisc_update((struct ip6ctlparam *)d, valid);
}
/* we normally notify single pcb here */
} else {
/* we normally notify any pcb here */
}
}
#endif /* INET6 */