1025 lines
25 KiB
C
1025 lines
25 KiB
C
/* $NetBSD: ah_input.c,v 1.41 2003/08/06 14:47:32 itojun Exp $ */
|
|
/* $KAME: ah_input.c,v 1.64 2001/09/04 08:43:19 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__KERNEL_RCSID(0, "$NetBSD: ah_input.c,v 1.41 2003/08/06 14:47:32 itojun Exp $");
|
|
|
|
#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>
|
|
|
|
#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*/
|
|
|
|
#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);
|
|
|
|
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;
|
|
}
|
|
nxt = ah->ah_nxt;
|
|
hlen = ip->ip_hl << 2;
|
|
|
|
/* 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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
{
|
|
#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 *);
|
|
/*
|
|
* 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 does not update m_pkthdr.len */
|
|
m->m_pkthdr.len += n->m_pkthdr.len;
|
|
m_cat(m, n);
|
|
}
|
|
|
|
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;
|
|
|
|
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;
|
|
}
|
|
ip6 = mtod(m, struct ip6_hdr *);
|
|
nxt = ah->ah_nxt;
|
|
|
|
/* 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;
|
|
}
|
|
|
|
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;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
|
|
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 = 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 *);
|
|
/*
|
|
* 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 does not update m_pkthdr.len */
|
|
m->m_pkthdr.len += n->m_pkthdr.len;
|
|
m_cat(m, n);
|
|
}
|
|
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 */
|