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freebsd/sys/netipsec/ipsec_input.c
Andrey V. Elsukov 962ac6c727 Change ipsec_address() and ipsec_logsastr() functions to take two
additional arguments - buffer and size of this buffer.

ipsec_address() is used to convert sockaddr structure to presentation
format. The IPv6 part of this function returns pointer to the on-stack
buffer and at the moment when it will be used by caller, it becames
invalid. IPv4 version uses 4 static buffers and returns pointer to
new buffer each time when it called. But anyway it is still possible
to get corrupted data when several threads will use this function.

ipsec_logsastr() is used to format string about SA entry. It also
uses static buffer and has the same problem with concurrent threads.

To fix these problems add the buffer pointer and size of this
buffer to arguments. Now each caller will pass buffer and its size
to these functions. Also convert all places where these functions
are used (except disabled code).

And now ipsec_address() uses inet_ntop() function from libkern.

PR:		185996
Differential Revision:	https://reviews.freebsd.org/D2321
Reviewed by:	gnn
Sponsored by:	Yandex LLC
2015-04-18 16:58:33 +00:00

969 lines
24 KiB
C

/* $FreeBSD$ */
/* $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.
*
* 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 "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include "opt_enc.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/syslog.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/pfil.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/xform.h>
#include <netinet6/ip6protosw.h>
#include <machine/in_cksum.h>
#include <machine/stdarg.h>
#ifdef DEV_ENC
#include <net/if_enc.h>
#endif
#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)
#ifdef INET
static void ipsec4_common_ctlinput(int, struct sockaddr *, void *, int);
#endif
/*
* 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[INET6_ADDRSTRLEN];
union sockaddr_union dst_address;
struct secasvar *sav;
u_int32_t spi;
int error;
#ifdef INET
#ifdef IPSEC_NAT_T
struct m_tag *tag;
#endif
#endif
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);
#ifdef IPSEC_NAT_T
/* Find the source port for NAT-T; see udp*_espdecap. */
tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL);
if (tag != NULL)
dst_address.sin.sin_port = ((u_int16_t *)(tag + 1))[1];
#endif /* IPSEC_NAT_T */
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);
KEY_FREESAV(&sav);
return error;
}
#ifdef INET
/*
* Common input handler for IPv4 AH, ESP, and IPCOMP.
*/
int
ipsec4_common_input(struct mbuf *m, ...)
{
va_list ap;
int off, nxt;
va_start(ap, m);
off = va_arg(ap, int);
nxt = va_arg(ap, int);
va_end(ap);
return ipsec_common_input(m, off, offsetof(struct ip, ip_p),
AF_INET, nxt);
}
int
ah4_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m;
int off;
m = *mp;
off = *offp;
*mp = NULL;
ipsec4_common_input(m, off, IPPROTO_AH);
return (IPPROTO_DONE);
}
void
ah4_ctlinput(int cmd, struct sockaddr *sa, void *v)
{
if (sa->sa_family == AF_INET &&
sa->sa_len == sizeof(struct sockaddr_in))
ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_AH);
}
int
esp4_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m;
int off;
m = *mp;
off = *offp;
mp = NULL;
ipsec4_common_input(m, off, IPPROTO_ESP);
return (IPPROTO_DONE);
}
void
esp4_ctlinput(int cmd, struct sockaddr *sa, void *v)
{
if (sa->sa_family == AF_INET &&
sa->sa_len == sizeof(struct sockaddr_in))
ipsec4_common_ctlinput(cmd, sa, v, IPPROTO_ESP);
}
int
ipcomp4_input(struct mbuf **mp, int *offp, int proto)
{
struct mbuf *m;
int off;
m = *mp;
off = *offp;
mp = NULL;
ipsec4_common_input(m, off, IPPROTO_IPCOMP);
return (IPPROTO_DONE);
}
/*
* 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[INET6_ADDRSTRLEN];
int prot, af, sproto, isr_prot;
struct ip *ip;
struct m_tag *mtag;
struct tdb_ident *tdbi;
struct secasindex *saidx;
int error;
#ifdef INET6
#ifdef notyet
char ip6buf[INET6_ADDRSTRLEN];
#endif
#endif
IPSEC_ASSERT(m != NULL, ("null mbuf"));
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));
/* Sanity check */
if (m == NULL) {
DPRINTF(("%s: null mbuf", __func__));
IPSEC_ISTAT(sproto, badkcr);
KEY_FREESAV(&sav);
return EINVAL;
}
if (skip != 0) {
/*
* Fix IPv4 header
* XXXGL: do we need this entire block?
*/
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;
#ifdef DEV_ENC
if_inc_counter(encif, IFCOUNTER_IPACKETS, 1);
if_inc_counter(encif, IFCOUNTER_IBYTES, m->m_pkthdr.len);
/* Pass the mbuf to enc0 for bpf and pfil. */
ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_BEFORE);
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
return (error);
#endif /* DEV_ENC */
/* 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 notyet
/* XXX PROXY address isn't recorded in SAH */
/*
* Check that the inner source address is the same as
* the proxy address, if available.
*/
if ((saidx->proxy.sa.sa_family == AF_INET &&
saidx->proxy.sin.sin_addr.s_addr !=
INADDR_ANY &&
ipn.ip_src.s_addr !=
saidx->proxy.sin.sin_addr.s_addr) ||
(saidx->proxy.sa.sa_family != AF_INET &&
saidx->proxy.sa.sa_family != 0)) {
DPRINTF(("%s: inner source address %s doesn't "
"correspond to expected proxy source %s, "
"SA %s/%08lx\n", __func__,
inet_ntoa4(ipn.ip_src),
ipsp_address(saidx->proxy),
ipsp_address(saidx->dst),
(u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, pdrops);
error = EACCES;
goto bad;
}
#endif /* notyet */
}
#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);
#ifdef notyet
/*
* Check that the inner source address is the same as
* the proxy address, if available.
*/
if ((saidx->proxy.sa.sa_family == AF_INET6 &&
!IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
!IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
&saidx->proxy.sin6.sin6_addr)) ||
(saidx->proxy.sa.sa_family != AF_INET6 &&
saidx->proxy.sa.sa_family != 0)) {
DPRINTF(("%s: inner source address %s doesn't "
"correspond to expected proxy source %s, "
"SA %s/%08lx\n", __func__,
ip6_sprintf(ip6buf, &ip6n.ip6_src),
ipsec_address(&saidx->proxy),
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, pdrops);
error = EACCES;
goto bad;
}
#endif /* notyet */
}
#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 and outer
* header was already stripped in xform_xxx_cb.
*/
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 tdb_ident), M_NOWAIT);
if (mtag == NULL) {
DPRINTF(("%s: failed to get tag\n", __func__));
IPSEC_ISTAT(sproto, hdrops);
error = ENOMEM;
goto bad;
}
tdbi = (struct tdb_ident *)(mtag + 1);
bcopy(&saidx->dst, &tdbi->dst, saidx->dst.sa.sa_len);
tdbi->proto = sproto;
tdbi->spi = sav->spi;
/* Cache those two for enc(4) in xform_ipip. */
tdbi->alg_auth = sav->alg_auth;
tdbi->alg_enc = sav->alg_enc;
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;
#ifdef DEV_ENC
/*
* Pass the mbuf to enc0 for bpf and pfil.
*/
if (prot == IPPROTO_IPIP)
ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER);
#ifdef INET6
if (prot == IPPROTO_IPV6)
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER);
#endif
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0)
return (error);
#endif /* DEV_ENC */
/*
* Re-dispatch via software interrupt.
*/
switch (prot) {
case IPPROTO_IPIP:
isr_prot = NETISR_IP;
break;
#ifdef INET6
case IPPROTO_IPV6:
isr_prot = NETISR_IPV6;
break;
#endif
default:
DPRINTF(("%s: cannot handle inner ip proto %d\n",
__func__, prot));
IPSEC_ISTAT(sproto, nopf);
error = EPFNOSUPPORT;
goto bad;
}
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));
return error;
}
return 0;
bad:
m_freem(m);
return error;
}
void
ipsec4_common_ctlinput(int cmd, struct sockaddr *sa, void *v, int proto)
{
/* XXX nothing just yet */
}
#endif /* INET */
#ifdef INET6
/* IPv6 AH wrapper. */
int
ipsec6_common_input(struct mbuf **mp, int *offp, int proto)
{
int l = 0;
int protoff;
struct ip6_ext ip6e;
if (*offp < sizeof(struct ip6_hdr)) {
DPRINTF(("%s: bad offset %u\n", __func__, *offp));
return IPPROTO_DONE;
} else if (*offp == sizeof(struct ip6_hdr)) {
protoff = offsetof(struct ip6_hdr, ip6_nxt);
} else {
/* Chase down the header chain... */
protoff = sizeof(struct ip6_hdr);
do {
protoff += l;
m_copydata(*mp, protoff, sizeof(ip6e),
(caddr_t) &ip6e);
if (ip6e.ip6e_nxt == IPPROTO_AH)
l = (ip6e.ip6e_len + 2) << 2;
else
l = (ip6e.ip6e_len + 1) << 3;
IPSEC_ASSERT(l > 0, ("l went zero or negative"));
} while (protoff + l < *offp);
/* Malformed packet check */
if (protoff + l != *offp) {
DPRINTF(("%s: bad packet header chain, protoff %u, "
"l %u, off %u\n", __func__, protoff, l, *offp));
IPSEC_ISTAT(proto, hdrops);
m_freem(*mp);
*mp = NULL;
return IPPROTO_DONE;
}
protoff += offsetof(struct ip6_ext, ip6e_nxt);
}
(void) ipsec_common_input(*mp, *offp, protoff, AF_INET6, proto);
return IPPROTO_DONE;
}
/*
* 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[INET6_ADDRSTRLEN];
int prot, af, sproto;
struct ip6_hdr *ip6;
struct m_tag *mtag;
struct tdb_ident *tdbi;
struct secasindex *saidx;
int nxt, isr_prot;
u_int8_t nxt8;
int error, nest;
#ifdef notyet
char ip6buf[INET6_ADDRSTRLEN];
#endif
IPSEC_ASSERT(m != NULL, ("null mbuf"));
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));
/* Sanity check */
if (m == NULL) {
DPRINTF(("%s: null mbuf", __func__));
IPSEC_ISTAT(sproto, badkcr);
error = EINVAL;
goto bad;
}
/* 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;
}
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;
#ifdef DEV_ENC
if_inc_counter(encif, IFCOUNTER_IPACKETS, 1);
if_inc_counter(encif, IFCOUNTER_IBYTES, m->m_pkthdr.len);
/* Pass the mbuf to enc0 for bpf and pfil. */
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_BEFORE);
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_BEFORE)) != 0)
return (error);
#endif /* DEV_ENC */
/* 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 notyet
/*
* Check that the inner source address is the same as
* the proxy address, if available.
*/
if ((saidx->proxy.sa.sa_family == AF_INET6 &&
!IN6_IS_ADDR_UNSPECIFIED(&saidx->proxy.sin6.sin6_addr) &&
!IN6_ARE_ADDR_EQUAL(&ip6n.ip6_src,
&saidx->proxy.sin6.sin6_addr)) ||
(saidx->proxy.sa.sa_family != AF_INET6 &&
saidx->proxy.sa.sa_family != 0)) {
DPRINTF(("%s: inner source address %s doesn't "
"correspond to expected proxy source %s, "
"SA %s/%08lx\n", __func__,
ip6_sprintf(ip6buf, &ip6n.ip6_src),
ipsec_address(&saidx->proxy),
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, pdrops);
error = EACCES;
goto bad;
}
#endif /* notyet */
}
#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;
#ifdef notyet
/*
* Check that the inner source address is the same as
* the proxy address, if available.
*/
if ((saidx->proxy.sa.sa_family == AF_INET &&
saidx->proxy.sin.sin_addr.s_addr != INADDR_ANY &&
ipn.ip_src.s_addr != saidx->proxy.sin.sin_addr.s_addr) ||
(saidx->proxy.sa.sa_family != AF_INET &&
saidx->proxy.sa.sa_family != 0)) {
DPRINTF(("%s: inner source address %s doesn't "
"correspond to expected proxy source %s, "
"SA %s/%08lx\n", __func__,
inet_ntoa4(ipn.ip_src),
ipsec_address(&saidx->proxy),
ipsec_address(&saidx->dst),
(u_long) ntohl(sav->spi)));
IPSEC_ISTAT(sproto, pdrops);
error = EACCES;
goto bad;
}
#endif /* notyet */
}
#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 tdb_ident), M_NOWAIT);
if (mtag == NULL) {
DPRINTF(("%s: failed to get tag\n", __func__));
IPSEC_ISTAT(sproto, hdrops);
error = ENOMEM;
goto bad;
}
tdbi = (struct tdb_ident *)(mtag + 1);
bcopy(&saidx->dst, &tdbi->dst, sizeof(union sockaddr_union));
tdbi->proto = sproto;
tdbi->spi = sav->spi;
/* Cache those two for enc(4) in xform_ipip. */
tdbi->alg_auth = sav->alg_auth;
tdbi->alg_enc = sav->alg_enc;
m_tag_prepend(m, mtag);
}
key_sa_recordxfer(sav, m);
#ifdef DEV_ENC
/*
* Pass the mbuf to enc0 for bpf and pfil.
*/
#ifdef INET
if (prot == IPPROTO_IPIP)
ipsec_bpf(m, sav, AF_INET, ENC_IN|ENC_AFTER);
#endif
if (prot == IPPROTO_IPV6)
ipsec_bpf(m, sav, AF_INET6, ENC_IN|ENC_AFTER);
if ((error = ipsec_filter(&m, PFIL_IN, ENC_IN|ENC_AFTER)) != 0)
return (error);
#endif /* DEV_ENC */
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;
}
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));
}
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);
}
return 0;
bad:
if (m)
m_freem(m);
return error;
}
void
esp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
{
struct ip6ctlparam *ip6cp = NULL;
struct mbuf *m = NULL;
struct ip6_hdr *ip6;
int off;
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;
off = 0; /* calm gcc */
}
if (ip6 != NULL) {
struct ip6ctlparam ip6cp1;
/*
* Notify the error to all possible sockets via pfctlinput2.
* Since the upper layer information (such as protocol type,
* source and destination ports) is embedded in the encrypted
* data and might have been cut, we can't directly call
* an upper layer ctlinput function. However, the pcbnotify
* function will consider source and destination addresses
* as well as the flow info value, and may be able to find
* some PCB that should be notified.
* Although pfctlinput2 will call esp6_ctlinput(), there is
* no possibility of an infinite loop of function calls,
* because we don't pass the inner IPv6 header.
*/
bzero(&ip6cp1, sizeof(ip6cp1));
ip6cp1.ip6c_src = ip6cp->ip6c_src;
pfctlinput2(cmd, sa, (void *)&ip6cp1);
/*
* Then go to special cases that need ESP header information.
* XXX: We assume that when ip6 is non NULL,
* M and OFF are valid.
*/
if (cmd == PRC_MSGSIZE) {
struct secasvar *sav;
u_int32_t spi;
int valid;
/* check header length before using m_copydata */
if (m->m_pkthdr.len < off + sizeof (struct esp))
return;
m_copydata(m, off + offsetof(struct esp, esp_spi),
sizeof(u_int32_t), (caddr_t) &spi);
/*
* Check to see if we have a valid SA corresponding to
* the address in the ICMP message payload.
*/
sav = KEY_ALLOCSA((union sockaddr_union *)sa,
IPPROTO_ESP, spi);
valid = (sav != NULL);
if (sav)
KEY_FREESAV(&sav);
/* XXX Further validation? */
/*
* Depending on whether the SA is "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(ip6cp, valid);
}
} else {
/* we normally notify any pcb here */
}
}
#endif /* INET6 */