gems-kernel/source/THIRDPARTY/xnu/bsd/netinet6/ah_input.c
2024-06-03 11:29:39 -05:00

1047 lines
28 KiB
C

/*
* Copyright (c) 2008-2023 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_input.c,v 1.1.2.6 2002/04/28 05:40:26 suz Exp $ */
/* $KAME: ah_input.c,v 1.67 2002/01/07 11:39:56 kjc 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/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mcache.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/if_ipsec.h>
#include <net/route.h>
#include <kern/cpu_number.h>
#include <kern/locks.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/in_pcb.h>
#include <netinet6/ip6_ecn.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/ipsec.h>
#include <netinet6/ipsec6.h>
#include <netinet6/ah.h>
#include <netinet6/ah6.h>
#include <netkey/key.h>
#include <netkey/keydb.h>
#if IPSEC_DEBUG
#include <netkey/key_debug.h>
#else
#define KEYDEBUG(lev, arg)
#endif
#include <net/kpi_protocol.h>
#include <netinet/kpi_ipfilter_var.h>
#include <mach/sdt.h>
#include <net/net_osdep.h>
#define IPLEN_FLIPPED
#if INET
void
ah4_input(struct mbuf *m, int off)
{
struct ip *ip;
struct ah *ah;
u_int32_t spi;
const struct ah_algorithm *algo;
size_t siz;
size_t siz1;
u_char *cksum;
struct secasvar *sav = NULL;
u_int16_t nxt;
u_int8_t hlen;
size_t stripsiz = 0;
sa_family_t ifamily;
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"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
}
/* Expect 32-bit aligned data pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip = mtod(m, struct ip *);
ah = (struct ah *)(void *)(((caddr_t)ip) + off);
nxt = ah->ah_nxt;
#ifdef _IP_VHL
hlen = (u_int8_t)(IP_VHL_HL(ip->ip_vhl) << 2);
#else
hlen = (u_int8_t)(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, IFSCOPE_NONE,
IPPROTO_AH, spi)) == 0) {
ipseclog((LOG_WARNING,
"IPv4 AH input: no key association found for spi %u\n",
(u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsecstat.in_nosa);
goto fail;
}
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah4_input called to allocate SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(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)));
IPSEC_STAT_INCREMENT(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)));
IPSEC_STAT_INCREMENT(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 "
"(%u, should be at least %u): %s\n",
(u_int32_t)siz1, (u_int32_t)siz,
ipsec4_logpacketstr(ip, spi)));
IPSEC_STAT_INCREMENT(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 %u): %s\n",
(ah->ah_len << 2) - sizoff, (u_int32_t)siz1,
ipsec4_logpacketstr(ip, spi)));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
if (m->m_len < off + sizeof(struct ah) + sizoff + siz1) {
VERIFY((off + sizeof(struct ah) + sizoff + siz1) <= INT_MAX);
m = m_pullup(m, (int)(off + sizeof(struct ah) + sizoff + siz1));
if (!m) {
ipseclog((LOG_DEBUG, "IPv4 AH input: can't pullup\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
/* Expect 32-bit aligned data ptr on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
ip = mtod(m, struct ip *);
ah = (struct ah *)(void *)(((caddr_t)ip) + off);
}
}
/*
* check for sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) {
if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) {
; /*okey*/
} else {
IPSEC_STAT_INCREMENT(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.
*/
cksum = (u_char *)kalloc_data(siz1, Z_NOWAIT);
if (!cksum) {
ipseclog((LOG_DEBUG, "IPv4 AH input: "
"couldn't alloc temporary region for cksum\n"));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
/*
* some of IP header fields are flipped to the host endian.
* convert them back to network endian. VERY stupid.
*/
if ((ip->ip_len + hlen) > UINT16_MAX) {
ipseclog((LOG_DEBUG, "IPv4 AH input: "
"bad length ip header len %u, total len %u\n",
ip->ip_len, hlen));
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
ip->ip_len = htons((u_int16_t)(ip->ip_len + hlen));
ip->ip_off = htons(ip->ip_off);
if (ah4_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) {
kfree_data(cksum, siz1);
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
IPSEC_STAT_INCREMENT(ipsecstat.in_ahhist[sav->alg_auth]);
/*
* flip them back.
*/
ip->ip_len = ntohs(ip->ip_len) - hlen;
ip->ip_off = ntohs(ip->ip_off);
{
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)));
kfree_data(cksum, siz1);
IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthfail);
goto fail;
}
}
kfree_data(cksum, siz1);
m->m_flags |= M_AUTHIPHDR;
m->m_flags |= M_AUTHIPDGM;
if (m->m_flags & M_AUTHIPHDR && m->m_flags & M_AUTHIPDGM) {
IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthsucc);
} else {
ipseclog((LOG_WARNING,
"authentication failed in IPv4 AH input: %s %s\n",
ipsec4_logpacketstr(ip, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsecstat.in_ahauthfail);
goto fail;
}
/*
* update sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) {
if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) {
IPSEC_STAT_INCREMENT(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(m, (int)(off + stripsiz), nxt, sav, &ifamily)) {
ifaddr_t ifa;
struct sockaddr_storage addr;
struct sockaddr_in *ipaddr;
/*
* 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, otos;
int sum;
if (ifamily == AF_INET6) {
ipseclog((LOG_NOTICE, "ipsec tunnel protocol mismatch "
"in IPv4 AH input: %s\n", ipsec_logsastr(sav)));
goto fail;
}
tos = ip->ip_tos;
m_adj(m, (int)(off + stripsiz));
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (!m) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
}
ip = mtod(m, struct ip *);
otos = ip->ip_tos;
/* ECN consideration. */
if (ip_ecn_egress(ip4_ipsec_ecn, &tos, &ip->ip_tos) == 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
if (otos != ip->ip_tos) {
sum = ~ntohs(ip->ip_sum) & 0xffff;
sum += (~otos & 0xffff) + ip->ip_tos;
sum = (sum >> 16) + (sum & 0xffff);
sum += (sum >> 16); /* add carry */
ip->ip_sum = htons(~sum & 0xffff);
}
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)));
IPSEC_STAT_INCREMENT(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->m_pkthdr.len);
if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0 ||
ipsec_incr_history_count(m, IPPROTO_IPV4, 0) != 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_nomem);
goto fail;
}
bzero(&addr, sizeof(addr));
ipaddr = (__typeof__(ipaddr)) & addr;
ipaddr->sin_family = AF_INET;
ipaddr->sin_len = sizeof(*ipaddr);
ipaddr->sin_addr = ip->ip_dst;
// update the receiving interface address based on the inner address
ifa = ifa_ifwithaddr((struct sockaddr *)&addr);
if (ifa) {
m->m_pkthdr.rcvif = ifa->ifa_ifp;
ifa_remref(ifa);
}
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
goto done;
} else {
goto fail;
}
}
if (proto_input(PF_INET, m) != 0) {
goto fail;
}
nxt = IPPROTO_DONE;
} else {
/*
* strip off AH.
*/
ip = mtod(m, struct ip *);
/*
* 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;
if (m->m_len < sizeof(*ip)) {
m = m_pullup(m, sizeof(*ip));
if (m == NULL) {
IPSEC_STAT_INCREMENT(ipsecstat.in_inval);
goto fail;
}
}
ip = mtod(m, struct ip *);
#ifdef IPLEN_FLIPPED
ip->ip_len = (u_short)(ip->ip_len - stripsiz);
#else
ip->ip_len = htons(ntohs(ip->ip_len) - stripsiz);
#endif
ip->ip_p = (u_char)nxt;
/* forget about IP hdr checksum, the check has already been passed */
key_sa_recordxfer(sav, m->m_pkthdr.len);
if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0) {
IPSEC_STAT_INCREMENT(ipsecstat.in_nomem);
goto fail;
}
DTRACE_IP6(receive, struct mbuf *, m, struct inpcb *, NULL,
struct ip *, ip, struct ifnet *, m->m_pkthdr.rcvif,
struct ip *, ip, struct ip6_hdr *, NULL);
if (nxt != IPPROTO_DONE) {
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
ip->ip_len = htons(ip->ip_len + hlen);
ip->ip_off = htons(ip->ip_off);
ip->ip_sum = 0;
ip->ip_sum = ip_cksum_hdr_in(m, hlen);
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
goto done;
} else {
goto fail;
}
}
if ((ip_protox[nxt]->pr_flags & PR_LASTHDR) != 0 &&
ipsec4_in_reject(m, NULL)) {
IPSEC_STAT_INCREMENT(ipsecstat.in_polvio);
goto fail;
}
ip_proto_dispatch_in(m, off, (u_int8_t)nxt, 0);
} else {
m_freem(m);
}
m = NULL;
}
done:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah4_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
IPSEC_STAT_INCREMENT(ipsecstat.in_success);
return;
fail:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah4_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
if (m) {
m_freem(m);
}
return;
}
#endif /* INET */
int
ah6_input(struct mbuf **mp, int *offp, int proto)
{
#pragma unused(proto)
struct mbuf *m = *mp;
int off = *offp;
struct ip6_hdr *ip6 = NULL;
struct ah *ah = NULL;
u_int32_t spi = 0;
const struct ah_algorithm *algo = NULL;
size_t siz = 0;
size_t siz1 = 0;
u_char *cksum = NULL;
struct secasvar *sav = NULL;
u_int16_t nxt = IPPROTO_DONE;
size_t stripsiz = 0;
sa_family_t ifamily = AF_UNSPEC;
IP6_EXTHDR_CHECK(m, off, sizeof(struct ah), {return IPPROTO_DONE;});
ah = (struct ah *)(void *)(mtod(m, caddr_t) + off);
/* Expect 32-bit aligned data pointer on strict-align platforms */
MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m);
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"));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
if ((sav = key_allocsa(AF_INET6,
(caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst, ip6_input_getsrcifscope(m),
IPPROTO_AH, spi)) == 0) {
ipseclog((LOG_WARNING,
"IPv6 AH input: no key association found for spi %u\n",
(u_int32_t)ntohl(spi)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_nosa);
goto fail;
}
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah6_input called to allocate SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(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)));
IPSEC_STAT_INCREMENT(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)));
IPSEC_STAT_INCREMENT(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 "
"(%u, should be at least %u): %s\n",
(u_int32_t)siz1, (u_int32_t)siz,
ipsec6_logpacketstr(ip6, spi)));
IPSEC_STAT_INCREMENT(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 %u): %s\n",
(ah->ah_len << 2) - sizoff, (u_int32_t)siz1,
ipsec6_logpacketstr(ip6, spi)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
VERIFY((sizeof(struct ah) + sizoff + siz1) <= INT_MAX);
IP6_EXTHDR_CHECK(m, off, (int)(sizeof(struct ah) + sizoff + siz1),
{goto fail;});
ip6 = mtod(m, struct ip6_hdr *);
ah = (struct ah *)(void *)(mtod(m, caddr_t) + off);
}
/*
* check for sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) {
if (ipsec_chkreplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) {
; /*okey*/
} else {
IPSEC_STAT_INCREMENT(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.
*/
cksum = (u_char *)kalloc_data(siz1, Z_NOWAIT);
if (!cksum) {
ipseclog((LOG_DEBUG, "IPv6 AH input: "
"couldn't alloc temporary region for cksum\n"));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
if (ah6_calccksum(m, (caddr_t)cksum, siz1, algo, sav)) {
kfree_data(cksum, siz1);
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
IPSEC_STAT_INCREMENT(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)));
kfree_data(cksum, siz1);
IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthfail);
goto fail;
}
}
kfree_data(cksum, siz1);
m->m_flags |= M_AUTHIPHDR;
m->m_flags |= M_AUTHIPDGM;
if (m->m_flags & M_AUTHIPHDR && m->m_flags & M_AUTHIPDGM) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthsucc);
} else {
ipseclog((LOG_WARNING,
"authentication failed in IPv6 AH input: %s %s\n",
ipsec6_logpacketstr(ip6, spi), ipsec_logsastr(sav)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_ahauthfail);
goto fail;
}
/*
* update sequence number.
*/
if ((sav->flags & SADB_X_EXT_OLD) == 0 && sav->replay[0] != NULL) {
if (ipsec_updatereplay(ntohl(((struct newah *)ah)->ah_seq), sav, 0)) {
IPSEC_STAT_INCREMENT(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(m, (int)(off + stripsiz), nxt, sav, &ifamily)) {
ifaddr_t ifa;
struct sockaddr_storage addr;
struct sockaddr_in6 *ip6addr;
/*
* 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*/
if (ifamily == AF_INET) {
ipseclog((LOG_NOTICE, "ipsec tunnel protocol mismatch "
"in IPv6 AH input: %s\n", ipsec_logsastr(sav)));
goto fail;
}
flowinfo = ip6->ip6_flow;
m_adj(m, (int)(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) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
}
ip6 = mtod(m, struct ip6_hdr *);
/* ECN consideration. */
if (ip6_ecn_egress(ip6_ipsec_ecn, &flowinfo, &ip6->ip6_flow) == 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
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)));
IPSEC_STAT_INCREMENT(ipsec6stat.in_inval);
goto fail;
}
/*
* should the inner packet be considered authentic?
* see comment in ah4_input().
*/
m->m_flags &= ~M_AUTHIPHDR;
m->m_flags &= ~M_AUTHIPDGM;
key_sa_recordxfer(sav, m->m_pkthdr.len);
if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0 ||
ipsec_incr_history_count(m, IPPROTO_IPV6, 0) != 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem);
goto fail;
}
bzero(&addr, sizeof(addr));
ip6addr = (__typeof__(ip6addr)) & addr;
ip6addr->sin6_family = AF_INET6;
ip6addr->sin6_len = sizeof(*ip6addr);
ip6addr->sin6_addr = ip6->ip6_dst;
// update the receiving interface address based on the inner address
ifa = ifa_ifwithaddr((struct sockaddr *)&addr);
if (ifa) {
m->m_pkthdr.rcvif = ifa->ifa_ifp;
ifa_remref(ifa);
}
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
nxt = IPPROTO_DONE;
goto done;
} else {
goto fail;
}
}
if (proto_input(PF_INET6, m) != 0) {
goto fail;
}
nxt = IPPROTO_DONE;
} else {
/*
* strip off AH.
*/
char *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 = (u_int8_t)nxt;
ip6 = mtod(m, struct ip6_hdr *);
/*
* 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;
ip6 = mtod(m, struct ip6_hdr *);
/* XXX jumbogram */
ip6->ip6_plen = htons((u_int16_t)(ntohs(ip6->ip6_plen) - stripsiz));
key_sa_recordxfer(sav, m->m_pkthdr.len);
if (ipsec_incr_history_count(m, IPPROTO_AH, spi) != 0) {
IPSEC_STAT_INCREMENT(ipsec6stat.in_nomem);
goto fail;
}
// Input via IPsec interface
lck_mtx_lock(sadb_mutex);
ifnet_t ipsec_if = sav->sah->ipsec_if;
if (ipsec_if != NULL) {
// If an interface is found, add a reference count before dropping the lock
ifnet_reference(ipsec_if);
}
lck_mtx_unlock(sadb_mutex);
if (ipsec_if != NULL) {
errno_t inject_error = ipsec_inject_inbound_packet(ipsec_if, m);
ifnet_release(ipsec_if);
if (inject_error == 0) {
m = NULL;
nxt = IPPROTO_DONE;
goto done;
} else {
goto fail;
}
}
}
done:
*offp = off;
*mp = m;
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah6_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
IPSEC_STAT_INCREMENT(ipsec6stat.in_success);
return nxt;
fail:
if (sav) {
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP ah6_input call free SA:0x%llx\n",
(uint64_t)VM_KERNEL_ADDRPERM(sav)));
key_freesav(sav, KEY_SADB_UNLOCKED);
}
if (m) {
m_freem(m);
*mp = NULL;
}
return IPPROTO_DONE;
}
void
ah6_ctlinput(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 = 0;
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 *)(void *)(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 *)(void *)sa;
sav = key_allocsa(AF_INET6,
(caddr_t)&sa6_src->sin6_addr,
(caddr_t)&sa6_dst->sin6_addr,
sa6_dst->sin6_scope_id,
IPPROTO_AH, ahp->ah_spi);
if (sav) {
if (sav->state == SADB_SASTATE_MATURE ||
sav->state == SADB_SASTATE_DYING) {
valid++;
}
key_freesav(sav, KEY_SADB_UNLOCKED);
}
/* 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 */
}
}