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freebsd-nq/sys/netipsec/ipsec_input.c
Andrey V. Elsukov fcf596178b Merge projects/ipsec into head/. 
Small summary
 -------------

o Almost all IPsec releated code was moved into sys/netipsec.
o New kernel modules added: ipsec.ko and tcpmd5.ko. New kernel
  option IPSEC_SUPPORT added. It enables support for loading
  and unloading of ipsec.ko and tcpmd5.ko kernel modules.
o IPSEC_NAT_T option was removed. Now NAT-T support is enabled by
  default. The UDP_ENCAP_ESPINUDP_NON_IKE encapsulation type
  support was removed. Added TCP/UDP checksum handling for
  inbound packets that were decapsulated by transport mode SAs.
  setkey(8) modified to show run-time NAT-T configuration of SA.
o New network pseudo interface if_ipsec(4) added. For now it is
  build as part of ipsec.ko module (or with IPSEC kernel).
  It implements IPsec virtual tunnels to create route-based VPNs.
o The network stack now invokes IPsec functions using special
  methods. The only one header file <netipsec/ipsec_support.h>
  should be included to declare all the needed things to work
  with IPsec.
o All IPsec protocols handlers (ESP/AH/IPCOMP protosw) were removed.
  Now these protocols are handled directly via IPsec methods.
o TCP_SIGNATURE support was reworked to be more close to RFC.
o PF_KEY SADB was reworked:
  - now all security associations stored in the single SPI namespace,
    and all SAs MUST have unique SPI.
  - several hash tables added to speed up lookups in SADB.
  - SADB now uses rmlock to protect access, and concurrent threads
    can do SA lookups in the same time.
  - many PF_KEY message handlers were reworked to reflect changes
    in SADB.
  - SADB_UPDATE message was extended to support new PF_KEY headers:
    SADB_X_EXT_NEW_ADDRESS_SRC and SADB_X_EXT_NEW_ADDRESS_DST. They
    can be used by IKE daemon to change SA addresses.
o ipsecrequest and secpolicy structures were cardinally changed to
  avoid locking protection for ipsecrequest. Now we support
  only limited number (4) of bundled SAs, but they are supported
  for both INET and INET6.
o INPCB security policy cache was introduced. Each PCB now caches
  used security policies to avoid SP lookup for each packet.
o For inbound security policies added the mode, when the kernel does
  check for full history of applied IPsec transforms.
o References counting rules for security policies and security
  associations were changed. The proper SA locking added into xform
  code.
o xform code was also changed. Now it is possible to unregister xforms.
  tdb_xxx structures were changed and renamed to reflect changes in
  SADB/SPDB, and changed rules for locking and refcounting.

Reviewed by:	gnn, wblock
Obtained from:	Yandex LLC
Relnotes:	yes
Sponsored by:	Yandex LLC
Differential Revision:	https://reviews.freebsd.org/D9352
2017-02-06 08:49:57 +00:00

681 lines
18 KiB
C
Raw Blame History

/* $OpenBSD: ipsec_input.c,v 1.63 2003/02/20 18:35:43 deraadt Exp $ */
/*-
* The authors of this code are John Ioannidis (ji@tla.org),
* Angelos D. Keromytis (kermit@csd.uch.gr) and
* Niels Provos (provos@physnet.uni-hamburg.de).
*
* This code was written by John Ioannidis for BSD/OS in Athens, Greece,
* in November 1995.
*
* Ported to OpenBSD and NetBSD, with additional transforms, in December 1996,
* by Angelos D. Keromytis.
*
* Additional transforms and features in 1997 and 1998 by Angelos D. Keromytis
* and Niels Provos.
*
* Additional features in 1999 by Angelos D. Keromytis.
*
* Copyright (C) 1995, 1996, 1997, 1998, 1999 by John Ioannidis,
* Angelos D. Keromytis and Niels Provos.
* Copyright (c) 2001, Angelos D. Keromytis.
* Copyright (c) 2016 Andrey V. Elsukov <ae@FreeBSD.org>
*
* Permission to use, copy, and modify this software with or without fee
* is hereby granted, provided that this entire notice is included in
* all copies of any software which is or includes a copy or
* modification of this software.
* You may use this code under the GNU public license if you so wish. Please
* contribute changes back to the authors under this freer than GPL license
* so that we may further the use of strong encryption without limitations to
* all.
*
* THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTY. IN PARTICULAR, NONE OF THE AUTHORS MAKES ANY
* REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE
* MERCHANTABILITY OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR
* PURPOSE.
*/
/*
* IPsec input processing.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.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/hhook.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_enc.h>
#include <net/netisr.h>
#include <net/vnet.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_var.h>
#include <netinet/ip6.h>
#ifdef INET6
#include <netinet6/ip6_var.h>
#endif
#include <netinet/in_pcb.h>
#ifdef INET6
#include <netinet/icmp6.h>
#endif
#include <netipsec/ipsec.h>
#ifdef INET6
#include <netipsec/ipsec6.h>
#endif
#include <netipsec/ah_var.h>
#include <netipsec/esp.h>
#include <netipsec/esp_var.h>
#include <netipsec/ipcomp_var.h>
#include <netipsec/key.h>
#include <netipsec/keydb.h>
#include <netipsec/key_debug.h>
#include <netipsec/xform.h>
#include <netinet6/ip6protosw.h>
#include <machine/in_cksum.h>
#include <machine/stdarg.h>
#define IPSEC_ISTAT(proto, name) do { \
if ((proto) == IPPROTO_ESP) \
ESPSTAT_INC(esps_##name); \
else if ((proto) == IPPROTO_AH) \
AHSTAT_INC(ahs_##name); \
else \
IPCOMPSTAT_INC(ipcomps_##name); \
} while (0)
/*
* ipsec_common_input gets called when an IPsec-protected packet
* is received by IPv4 or IPv6. Its job is to find the right SA
* and call the appropriate transform. The transform callback
* takes care of further processing (like ingress filtering).
*/
static int
ipsec_common_input(struct mbuf *m, int skip, int protoff, int af, int sproto)
{
char buf[IPSEC_ADDRSTRLEN];
union sockaddr_union dst_address;
struct secasvar *sav;
uint32_t spi;
int error;
IPSEC_ISTAT(sproto, input);
IPSEC_ASSERT(m != NULL, ("null packet"));
IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
sproto == IPPROTO_IPCOMP,
("unexpected security protocol %u", sproto));
if ((sproto == IPPROTO_ESP && !V_esp_enable) ||
(sproto == IPPROTO_AH && !V_ah_enable) ||
(sproto == IPPROTO_IPCOMP && !V_ipcomp_enable)) {
m_freem(m);
IPSEC_ISTAT(sproto, pdrops);
return EOPNOTSUPP;
}
if (m->m_pkthdr.len - skip < 2 * sizeof (u_int32_t)) {
m_freem(m);
IPSEC_ISTAT(sproto, hdrops);
DPRINTF(("%s: packet too small\n", __func__));
return EINVAL;
}
/* Retrieve the SPI from the relevant IPsec header */
if (sproto == IPPROTO_ESP)
m_copydata(m, skip, sizeof(u_int32_t), (caddr_t) &spi);
else if (sproto == IPPROTO_AH)
m_copydata(m, skip + sizeof(u_int32_t), sizeof(u_int32_t),
(caddr_t) &spi);
else if (sproto == IPPROTO_IPCOMP) {
u_int16_t cpi;
m_copydata(m, skip + sizeof(u_int16_t), sizeof(u_int16_t),
(caddr_t) &cpi);
spi = ntohl(htons(cpi));
}
/*
* Find the SA and (indirectly) call the appropriate
* kernel crypto routine. The resulting mbuf chain is a valid
* IP packet ready to go through input processing.
*/
bzero(&dst_address, sizeof (dst_address));
dst_address.sa.sa_family = af;
switch (af) {
#ifdef INET
case AF_INET:
dst_address.sin.sin_len = sizeof(struct sockaddr_in);
m_copydata(m, offsetof(struct ip, ip_dst),
sizeof(struct in_addr),
(caddr_t) &dst_address.sin.sin_addr);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
dst_address.sin6.sin6_len = sizeof(struct sockaddr_in6);
m_copydata(m, offsetof(struct ip6_hdr, ip6_dst),
sizeof(struct in6_addr),
(caddr_t) &dst_address.sin6.sin6_addr);
/* We keep addresses in SADB without embedded scope id */
if (IN6_IS_SCOPE_LINKLOCAL(&dst_address.sin6.sin6_addr)) {
/* XXX: sa6_recoverscope() */
dst_address.sin6.sin6_scope_id =
ntohs(dst_address.sin6.sin6_addr.s6_addr16[1]);
dst_address.sin6.sin6_addr.s6_addr16[1] = 0;
}
break;
#endif /* INET6 */
default:
DPRINTF(("%s: unsupported protocol family %u\n", __func__, af));
m_freem(m);
IPSEC_ISTAT(sproto, nopf);
return EPFNOSUPPORT;
}
/* NB: only pass dst since key_allocsa follows RFC2401 */
sav = key_allocsa(&dst_address, sproto, spi);
if (sav == NULL) {
DPRINTF(("%s: no key association found for SA %s/%08lx/%u\n",
__func__, ipsec_address(&dst_address, buf, sizeof(buf)),
(u_long) ntohl(spi), sproto));
IPSEC_ISTAT(sproto, notdb);
m_freem(m);
return ENOENT;
}
if (sav->tdb_xform == NULL) {
DPRINTF(("%s: attempted to use uninitialized SA %s/%08lx/%u\n",
__func__, ipsec_address(&dst_address, buf, sizeof(buf)),
(u_long) ntohl(spi), sproto));
IPSEC_ISTAT(sproto, noxform);
key_freesav(&sav);
m_freem(m);
return ENXIO;
}
/*
* Call appropriate transform and return -- callback takes care of
* everything else.
*/
error = (*sav->tdb_xform->xf_input)(m, sav, skip, protoff);
if (error != 0)
key_freesav(&sav);
return (error);
}
#ifdef INET
extern struct protosw inetsw[];
/*
* IPSEC_INPUT() method implementation for IPv4.
* 0 - Permitted by inbound security policy for further processing.
* EACCES - Forbidden by inbound security policy.
* EINPROGRESS - consumed by IPsec.
*/
int
ipsec4_input(struct mbuf *m, int offset, int proto)
{
switch (proto) {
case IPPROTO_AH:
case IPPROTO_ESP:
case IPPROTO_IPCOMP:
/* Do inbound IPsec processing for AH/ESP/IPCOMP */
ipsec_common_input(m, offset,
offsetof(struct ip, ip_p), AF_INET, proto);
return (EINPROGRESS); /* mbuf consumed by IPsec */
default:
/*
* Protocols with further headers get their IPsec treatment
* within the protocol specific processing.
*/
if ((inetsw[ip_protox[proto]].pr_flags & PR_LASTHDR) == 0)
return (0);
/* FALLTHROUGH */
};
/*
* Enforce IPsec policy checking if we are seeing last header.
*/
if (ipsec4_in_reject(m, NULL) != 0) {
/* Forbidden by inbound security policy */
m_freem(m);
return (EACCES);
}
return (0);
}
/*
* IPsec input callback for INET protocols.
* This routine is called as the transform callback.
* Takes care of filtering and other sanity checks on
* the processed packet.
*/
int
ipsec4_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip,
int protoff)
{
char buf[IPSEC_ADDRSTRLEN];
struct ipsec_ctx_data ctx;
struct xform_history *xh;
struct secasindex *saidx;
struct m_tag *mtag;
struct ip *ip;
int error, prot, af, sproto, isr_prot;
IPSEC_ASSERT(sav != NULL, ("null SA"));
IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
saidx = &sav->sah->saidx;
af = saidx->dst.sa.sa_family;
IPSEC_ASSERT(af == AF_INET, ("unexpected af %u", af));
sproto = saidx->proto;
IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
sproto == IPPROTO_IPCOMP,
("unexpected security protocol %u", sproto));
if (skip != 0) {
/*
* Fix IPv4 header
*/
if (m->m_len < skip && (m = m_pullup(m, skip)) == NULL) {
DPRINTF(("%s: processing failed for SA %s/%08lx\n",
__func__, ipsec_address(&sav->sah->saidx.dst,
buf, sizeof(buf)), (u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, hdrops);
error = ENOBUFS;
goto bad;
}
ip = mtod(m, struct ip *);
ip->ip_len = htons(m->m_pkthdr.len);
ip->ip_sum = 0;
ip->ip_sum = in_cksum(m, ip->ip_hl << 2);
} else {
ip = mtod(m, struct ip *);
}
prot = ip->ip_p;
/*
* Check that we have NAT-T enabled and apply transport mode
* decapsulation NAT procedure (RFC3948).
* Do this before invoking into the PFIL.
*/
if (sav->natt != NULL &&
(prot == IPPROTO_UDP || prot == IPPROTO_TCP))
udp_ipsec_adjust_cksum(m, sav, prot, skip);
IPSEC_INIT_CTX(&ctx, &m, sav, AF_INET, IPSEC_ENC_BEFORE);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_IN)) != 0)
goto bad;
ip = mtod(m, struct ip *); /* update pointer */
/* IP-in-IP encapsulation */
if (prot == IPPROTO_IPIP &&
saidx->mode != IPSEC_MODE_TRANSPORT) {
if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
IPSEC_ISTAT(sproto, hdrops);
error = EINVAL;
goto bad;
}
/* enc0: strip outer IPv4 header */
m_striphdr(m, 0, ip->ip_hl << 2);
}
#ifdef INET6
/* IPv6-in-IP encapsulation. */
else if (prot == IPPROTO_IPV6 &&
saidx->mode != IPSEC_MODE_TRANSPORT) {
if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
IPSEC_ISTAT(sproto, hdrops);
error = EINVAL;
goto bad;
}
/* enc0: strip IPv4 header, keep IPv6 header only */
m_striphdr(m, 0, ip->ip_hl << 2);
}
#endif /* INET6 */
else if (prot != IPPROTO_IPV6 && saidx->mode == IPSEC_MODE_ANY) {
/*
* When mode is wildcard, inner protocol is IPv6 and
* we have no INET6 support - drop this packet a bit later.
* In other cases we assume transport mode. Set prot to
* correctly choose netisr.
*/
prot = IPPROTO_IPIP;
}
/*
* Record what we've done to the packet (under what SA it was
* processed).
*/
if (sproto != IPPROTO_IPCOMP) {
mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
sizeof(struct xform_history), M_NOWAIT);
if (mtag == NULL) {
DPRINTF(("%s: failed to get tag\n", __func__));
IPSEC_ISTAT(sproto, hdrops);
error = ENOMEM;
goto bad;
}
xh = (struct xform_history *)(mtag + 1);
bcopy(&saidx->dst, &xh->dst, saidx->dst.sa.sa_len);
xh->spi = sav->spi;
xh->proto = sproto;
xh->mode = saidx->mode;
m_tag_prepend(m, mtag);
}
key_sa_recordxfer(sav, m); /* record data transfer */
/*
* In transport mode requeue decrypted mbuf back to IPv4 protocol
* handler. This is necessary to correctly expose rcvif.
*/
if (saidx->mode == IPSEC_MODE_TRANSPORT)
prot = IPPROTO_IPIP;
/*
* Re-dispatch via software interrupt.
*/
switch (prot) {
case IPPROTO_IPIP:
isr_prot = NETISR_IP;
af = AF_INET;
break;
#ifdef INET6
case IPPROTO_IPV6:
isr_prot = NETISR_IPV6;
af = AF_INET6;
break;
#endif
default:
DPRINTF(("%s: cannot handle inner ip proto %d\n",
__func__, prot));
IPSEC_ISTAT(sproto, nopf);
error = EPFNOSUPPORT;
goto bad;
}
IPSEC_INIT_CTX(&ctx, &m, sav, af, IPSEC_ENC_AFTER);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_IN)) != 0)
goto bad;
/* Handle virtual tunneling interfaces */
if (saidx->mode == IPSEC_MODE_TUNNEL)
error = ipsec_if_input(m, sav, af);
if (error == 0) {
error = netisr_queue_src(isr_prot, (uintptr_t)sav->spi, m);
if (error) {
IPSEC_ISTAT(sproto, qfull);
DPRINTF(("%s: queue full; proto %u packet dropped\n",
__func__, sproto));
}
}
key_freesav(&sav);
return (error);
bad:
key_freesav(&sav);
if (m != NULL)
m_freem(m);
return (error);
}
#endif /* INET */
#ifdef INET6
/*
* IPSEC_INPUT() method implementation for IPv6.
* 0 - Permitted by inbound security policy for further processing.
* EACCES - Forbidden by inbound security policy.
* EINPROGRESS - consumed by IPsec.
*/
int
ipsec6_input(struct mbuf *m, int offset, int proto)
{
switch (proto) {
case IPPROTO_AH:
case IPPROTO_ESP:
case IPPROTO_IPCOMP:
/* Do inbound IPsec processing for AH/ESP/IPCOMP */
ipsec_common_input(m, offset,
offsetof(struct ip6_hdr, ip6_nxt), AF_INET6, proto);
return (EINPROGRESS); /* mbuf consumed by IPsec */
default:
/*
* Protocols with further headers get their IPsec treatment
* within the protocol specific processing.
*/
if ((inet6sw[ip6_protox[proto]].pr_flags & PR_LASTHDR) == 0)
return (0);
/* FALLTHROUGH */
};
/*
* Enforce IPsec policy checking if we are seeing last header.
*/
if (ipsec6_in_reject(m, NULL) != 0) {
/* Forbidden by inbound security policy */
m_freem(m);
return (EACCES);
}
return (0);
}
/*
* IPsec input callback, called by the transform callback. Takes care of
* filtering and other sanity checks on the processed packet.
*/
int
ipsec6_common_input_cb(struct mbuf *m, struct secasvar *sav, int skip,
int protoff)
{
char buf[IPSEC_ADDRSTRLEN];
struct ipsec_ctx_data ctx;
struct xform_history *xh;
struct secasindex *saidx;
struct ip6_hdr *ip6;
struct m_tag *mtag;
int prot, af, sproto;
int nxt, isr_prot;
int error, nest;
uint8_t nxt8;
IPSEC_ASSERT(sav != NULL, ("null SA"));
IPSEC_ASSERT(sav->sah != NULL, ("null SAH"));
saidx = &sav->sah->saidx;
af = saidx->dst.sa.sa_family;
IPSEC_ASSERT(af == AF_INET6, ("unexpected af %u", af));
sproto = saidx->proto;
IPSEC_ASSERT(sproto == IPPROTO_ESP || sproto == IPPROTO_AH ||
sproto == IPPROTO_IPCOMP,
("unexpected security protocol %u", sproto));
/* Fix IPv6 header */
if (m->m_len < sizeof(struct ip6_hdr) &&
(m = m_pullup(m, sizeof(struct ip6_hdr))) == NULL) {
DPRINTF(("%s: processing failed for SA %s/%08lx\n",
__func__, ipsec_address(&sav->sah->saidx.dst, buf,
sizeof(buf)), (u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, hdrops);
error = EACCES;
goto bad;
}
IPSEC_INIT_CTX(&ctx, &m, sav, af, IPSEC_ENC_BEFORE);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_IN)) != 0)
goto bad;
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_plen = htons(m->m_pkthdr.len - sizeof(struct ip6_hdr));
/* Save protocol */
m_copydata(m, protoff, 1, &nxt8);
prot = nxt8;
/* IPv6-in-IP encapsulation */
if (prot == IPPROTO_IPV6 &&
saidx->mode != IPSEC_MODE_TRANSPORT) {
if (m->m_pkthdr.len - skip < sizeof(struct ip6_hdr)) {
IPSEC_ISTAT(sproto, hdrops);
error = EINVAL;
goto bad;
}
/* ip6n will now contain the inner IPv6 header. */
m_striphdr(m, 0, skip);
skip = 0;
}
#ifdef INET
/* IP-in-IP encapsulation */
else if (prot == IPPROTO_IPIP &&
saidx->mode != IPSEC_MODE_TRANSPORT) {
if (m->m_pkthdr.len - skip < sizeof(struct ip)) {
IPSEC_ISTAT(sproto, hdrops);
error = EINVAL;
goto bad;
}
/* ipn will now contain the inner IPv4 header */
m_striphdr(m, 0, skip);
skip = 0;
}
#endif /* INET */
else {
prot = IPPROTO_IPV6; /* for correct BPF processing */
}
/*
* Record what we've done to the packet (under what SA it was
* processed).
*/
if (sproto != IPPROTO_IPCOMP) {
mtag = m_tag_get(PACKET_TAG_IPSEC_IN_DONE,
sizeof(struct xform_history), M_NOWAIT);
if (mtag == NULL) {
DPRINTF(("%s: failed to get tag\n", __func__));
IPSEC_ISTAT(sproto, hdrops);
error = ENOMEM;
goto bad;
}
xh = (struct xform_history *)(mtag + 1);
bcopy(&saidx->dst, &xh->dst, saidx->dst.sa.sa_len);
xh->spi = sav->spi;
xh->proto = sproto;
xh->mode = saidx->mode;
m_tag_prepend(m, mtag);
}
key_sa_recordxfer(sav, m);
#ifdef INET
if (prot == IPPROTO_IPIP)
af = AF_INET;
else
#endif
af = AF_INET6;
IPSEC_INIT_CTX(&ctx, &m, sav, af, IPSEC_ENC_AFTER);
if ((error = ipsec_run_hhooks(&ctx, HHOOK_TYPE_IPSEC_IN)) != 0)
goto bad;
if (skip == 0) {
/*
* We stripped outer IPv6 header.
* Now we should requeue decrypted packet via netisr.
*/
switch (prot) {
#ifdef INET
case IPPROTO_IPIP:
isr_prot = NETISR_IP;
break;
#endif
case IPPROTO_IPV6:
isr_prot = NETISR_IPV6;
break;
default:
DPRINTF(("%s: cannot handle inner ip proto %d\n",
__func__, prot));
IPSEC_ISTAT(sproto, nopf);
error = EPFNOSUPPORT;
goto bad;
}
/* Handle virtual tunneling interfaces */
if (saidx->mode == IPSEC_MODE_TUNNEL)
error = ipsec_if_input(m, sav, af);
if (error == 0) {
error = netisr_queue_src(isr_prot,
(uintptr_t)sav->spi, m);
if (error) {
IPSEC_ISTAT(sproto, qfull);
DPRINTF(("%s: queue full; proto %u packet"
" dropped\n", __func__, sproto));
}
}
key_freesav(&sav);
return (error);
}
/*
* See the end of ip6_input for this logic.
* IPPROTO_IPV[46] case will be processed just like other ones
*/
nest = 0;
nxt = nxt8;
while (nxt != IPPROTO_DONE) {
if (V_ip6_hdrnestlimit && (++nest > V_ip6_hdrnestlimit)) {
IP6STAT_INC(ip6s_toomanyhdr);
error = EINVAL;
goto bad;
}
/*
* Protection against faulty packet - there should be
* more sanity checks in header chain processing.
*/
if (m->m_pkthdr.len < skip) {
IP6STAT_INC(ip6s_tooshort);
in6_ifstat_inc(m->m_pkthdr.rcvif, ifs6_in_truncated);
error = EINVAL;
goto bad;
}
/*
* Enforce IPsec policy checking if we are seeing last header.
* note that we do not visit this with protocols with pcb layer
* code - like udp/tcp/raw ip.
*/
if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
ipsec6_in_reject(m, NULL)) {
error = EINVAL;
goto bad;
}
nxt = (*inet6sw[ip6_protox[nxt]].pr_input)(&m, &skip, nxt);
}
key_freesav(&sav);
return (0);
bad:
key_freesav(&sav);
if (m)
m_freem(m);
return (error);
}
#endif /* INET6 */
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