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NetBSD/sys/netipsec/ipsec.c

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/* $NetBSD: ipsec.c,v 1.66 2015/04/01 02:49:44 ozaki-r Exp $ */
/* $FreeBSD: /usr/local/www/cvsroot/FreeBSD/src/sys/netipsec/ipsec.c,v 1.2.2.2 2003/07/01 01:38:13 sam Exp $ */
/* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ipsec.c,v 1.66 2015/04/01 02:49:44 ozaki-r Exp $");
/*
* IPsec controller part.
*/
#include "opt_inet.h"
#ifdef __FreeBSD__
#include "opt_inet6.h"
#endif
#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/socketvar.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/kauth.h>
#include <net/if.h>
#include <net/route.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/udp.h>
#include <netinet/udp_var.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <netinet/ip_icmp.h>
#include <netinet/ip_private.h>
#include <netinet/ip6.h>
#ifdef INET6
#include <netinet6/ip6_var.h>
#endif
#include <netinet/in_pcb.h>
#ifdef INET6
#include <netinet6/in6_pcb.h>
#include <netinet/icmp6.h>
#endif
#include <netipsec/ipsec.h>
#include <netipsec/ipsec_var.h>
#include <netipsec/ipsec_private.h>
#ifdef INET6
#include <netipsec/ipsec6.h>
#endif
#include <netipsec/ah_var.h>
#include <netipsec/esp_var.h>
#include <netipsec/ipcomp.h> /*XXX*/
#include <netipsec/ipcomp_var.h>
#include <netipsec/key.h>
#include <netipsec/keydb.h>
#include <netipsec/key_debug.h>
#include <netipsec/xform.h>
#include <netipsec/ipsec_osdep.h>
#include <net/net_osdep.h>
int ipsec_used = 0;
int ipsec_enabled = 1;
#ifdef IPSEC_DEBUG
int ipsec_debug = 1;
/*
* When set to 1, IPsec will send packets with the same sequence number.
* This allows to verify if the other side has proper replay attacks detection.
*/
int ipsec_replay = 0;
/*
* When set 1, IPsec will send packets with corrupted HMAC.
* This allows to verify if the other side properly detects modified packets.
*/
int ipsec_integrity = 0;
#else
int ipsec_debug = 0;
#endif
percpu_t *ipsecstat_percpu;
int ip4_ah_offsetmask = 0; /* maybe IP_DF? */
int ip4_ipsec_dfbit = 2; /* DF bit on encap. 0: clear 1: set 2: copy */
int ip4_esp_trans_deflev = IPSEC_LEVEL_USE;
int ip4_esp_net_deflev = IPSEC_LEVEL_USE;
int ip4_ah_trans_deflev = IPSEC_LEVEL_USE;
int ip4_ah_net_deflev = IPSEC_LEVEL_USE;
struct secpolicy ip4_def_policy;
int ip4_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
int ip4_esp_randpad = -1;
#ifdef __NetBSD__
u_int ipsec_spdgen = 1; /* SPD generation # */
static struct secpolicy *ipsec_checkpcbcache (struct mbuf *,
struct inpcbpolicy *, int);
static int ipsec_fillpcbcache (struct inpcbpolicy *, struct mbuf *,
struct secpolicy *, int);
static int ipsec_invalpcbcache (struct inpcbpolicy *, int);
#endif /* __NetBSD__ */
/*
* Crypto support requirements:
*
* 1 require hardware support
* -1 require software support
* 0 take anything
*/
int crypto_support = 0;
static struct secpolicy *ipsec_getpolicybysock(struct mbuf *, u_int,
PCB_T *, int *);
#ifdef __FreeBSD__
SYSCTL_DECL(_net_inet_ipsec);
/* net.inet.ipsec */
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY,
def_policy, CTLFLAG_RW, &ip4_def_policy.policy, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
CTLFLAG_RW, &ip4_esp_trans_deflev, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
CTLFLAG_RW, &ip4_esp_net_deflev, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
CTLFLAG_RW, &ip4_ah_trans_deflev, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
CTLFLAG_RW, &ip4_ah_net_deflev, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS,
ah_cleartos, CTLFLAG_RW, &ip4_ah_cleartos, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK,
ah_offsetmask, CTLFLAG_RW, &ip4_ah_offsetmask, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DFBIT,
dfbit, CTLFLAG_RW, &ip4_ipsec_dfbit, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ECN,
ecn, CTLFLAG_RW, &ip4_ipsec_ecn, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_DEBUG,
debug, CTLFLAG_RW, &ipsec_debug, 0, "");
SYSCTL_INT(_net_inet_ipsec, IPSECCTL_ESP_RANDPAD,
esp_randpad, CTLFLAG_RW, &ip4_esp_randpad, 0, "");
SYSCTL_INT(_net_inet_ipsec, OID_AUTO,
crypto_support, CTLFLAG_RW, &crypto_support,0, "");
SYSCTL_STRUCT(_net_inet_ipsec, OID_AUTO,
ipsecstats, CTLFLAG_RD, &newipsecstat, newipsecstat, "");
SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_replay, CTLFLAG_RW, &ipsec_replay, 0,
"Emulate replay attack");
SYSCTL_INT(_net_inet_ipsec, OID_AUTO, test_integrity, CTLFLAG_RW,
&ipsec_integrity, 0, "Emulate man-in-the-middle attack");
#endif /* __FreeBSD__ */
#ifdef INET6
int ip6_esp_trans_deflev = IPSEC_LEVEL_USE;
int ip6_esp_net_deflev = IPSEC_LEVEL_USE;
int ip6_ah_trans_deflev = IPSEC_LEVEL_USE;
int ip6_ah_net_deflev = IPSEC_LEVEL_USE;
struct secpolicy ip6_def_policy;
int ip6_ipsec_ecn = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
int ip6_esp_randpad = -1;
#ifdef __FreeBSD__
SYSCTL_DECL(_net_inet6_ipsec6);
/* net.inet6.ipsec6 */
#ifdef COMPAT_KAME
SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD,
0,0, compat_ipsecstats_sysctl, "S", "");
#endif /* COMPAT_KAME */
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY,
def_policy, CTLFLAG_RW, &ip4_def_policy.policy, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
CTLFLAG_RW, &ip6_esp_trans_deflev, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
CTLFLAG_RW, &ip6_esp_net_deflev, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
CTLFLAG_RW, &ip6_ah_trans_deflev, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
CTLFLAG_RW, &ip6_ah_net_deflev, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ECN,
ecn, CTLFLAG_RW, &ip6_ipsec_ecn, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG,
debug, CTLFLAG_RW, &ipsec_debug, 0, "");
SYSCTL_INT(_net_inet6_ipsec6, IPSECCTL_ESP_RANDPAD,
esp_randpad, CTLFLAG_RW, &ip6_esp_randpad, 0, "");
#endif /* __FreeBSD__ */
#endif /* INET6 */
static int ipsec4_setspidx_inpcb (struct mbuf *, struct inpcb *);
#ifdef INET6
static int ipsec6_setspidx_in6pcb (struct mbuf *, struct in6pcb *);
#endif
static int ipsec_setspidx (struct mbuf *, struct secpolicyindex *, int);
static void ipsec4_get_ulp (struct mbuf *m, struct secpolicyindex *, int);
static int ipsec4_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *);
#ifdef INET6
static void ipsec6_get_ulp (struct mbuf *m, struct secpolicyindex *, int);
static int ipsec6_setspidx_ipaddr (struct mbuf *, struct secpolicyindex *);
#endif
static void ipsec_delpcbpolicy (struct inpcbpolicy *);
static struct secpolicy *ipsec_deepcopy_policy (const struct secpolicy *);
static int ipsec_set_policy (struct secpolicy **, int, const void *, size_t,
kauth_cred_t);
static int ipsec_get_policy (struct secpolicy *, struct mbuf **);
static void vshiftl (unsigned char *, int, int);
static size_t ipsec_hdrsiz (const struct secpolicy *);
#ifdef __NetBSD__
/*
* Try to validate and use cached policy on a PCB.
*/
static struct secpolicy *
ipsec_checkpcbcache(struct mbuf *m, struct inpcbpolicy *pcbsp, int dir)
{
struct secpolicyindex spidx;
switch (dir) {
case IPSEC_DIR_INBOUND:
case IPSEC_DIR_OUTBOUND:
case IPSEC_DIR_ANY:
break;
default:
return NULL;
}
#ifdef DIAGNOSTIC
if (pcbsp == NULL) {
printf("%s: NULL pcbsp\n", __func__);
/* XXX panic? */
return NULL;
}
#endif
#ifdef DIAGNOSTIC
if (dir >= sizeof(pcbsp->sp_cache)/sizeof(pcbsp->sp_cache[0]))
panic("dir too big in ipsec_checkpcbcache");
#endif
/* SPD table change invalidate all the caches. */
if (ipsec_spdgen != pcbsp->sp_cache[dir].cachegen) {
ipsec_invalpcbcache(pcbsp, dir);
return NULL;
}
if (!pcbsp->sp_cache[dir].cachesp)
return NULL;
if (pcbsp->sp_cache[dir].cachesp->state != IPSEC_SPSTATE_ALIVE) {
ipsec_invalpcbcache(pcbsp, dir);
return NULL;
}
if ((pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) == 0) {
if (!pcbsp->sp_cache[dir].cachesp)
return NULL;
if (ipsec_setspidx(m, &spidx, 1) != 0)
return NULL;
/*
* We have to make an exact match here since the cached rule
* might have lower priority than a rule that would otherwise
* have matched the packet.
*/
if (memcmp(&pcbsp->sp_cache[dir].cacheidx, &spidx, sizeof(spidx)))
return NULL;
} else {
/*
* The pcb is connected, and the L4 code is sure that:
* - outgoing side uses inp_[lf]addr
* - incoming side looks up policy after inpcb lookup
* and address pair is know to be stable. We do not need
* to generate spidx again, nor check the address match again.
*
* For IPv4/v6 SOCK_STREAM sockets, this assumptions holds
* and there are calls to ipsec_pcbconn() from in_pcbconnect().
*/
}
pcbsp->sp_cache[dir].cachesp->lastused = time_second;
pcbsp->sp_cache[dir].cachesp->refcnt++;
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP %s cause refcnt++:%d SP:%p\n", __func__,
pcbsp->sp_cache[dir].cachesp->refcnt,
pcbsp->sp_cache[dir].cachesp));
return pcbsp->sp_cache[dir].cachesp;
}
static int
ipsec_fillpcbcache(struct inpcbpolicy *pcbsp, struct mbuf *m,
struct secpolicy *sp, int dir)
{
switch (dir) {
case IPSEC_DIR_INBOUND:
case IPSEC_DIR_OUTBOUND:
break;
default:
return EINVAL;
}
#ifdef DIAGNOSTIC
if (dir >= sizeof(pcbsp->sp_cache)/sizeof(pcbsp->sp_cache[0]))
panic("dir too big in ipsec_fillpcbcache");
#endif
if (pcbsp->sp_cache[dir].cachesp)
KEY_FREESP(&pcbsp->sp_cache[dir].cachesp);
pcbsp->sp_cache[dir].cachesp = NULL;
pcbsp->sp_cache[dir].cachehint = IPSEC_PCBHINT_MAYBE;
if (ipsec_setspidx(m, &pcbsp->sp_cache[dir].cacheidx, 1) != 0) {
return EINVAL;
}
pcbsp->sp_cache[dir].cachesp = sp;
if (pcbsp->sp_cache[dir].cachesp) {
pcbsp->sp_cache[dir].cachesp->refcnt++;
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP %s cause refcnt++:%d SP:%p\n", __func__,
pcbsp->sp_cache[dir].cachesp->refcnt,
pcbsp->sp_cache[dir].cachesp));
/*
* If the PCB is connected, we can remember a hint to
* possibly short-circuit IPsec processing in other places.
*/
if (pcbsp->sp_cacheflags & IPSEC_PCBSP_CONNECTED) {
switch (pcbsp->sp_cache[dir].cachesp->policy) {
case IPSEC_POLICY_NONE:
case IPSEC_POLICY_BYPASS:
pcbsp->sp_cache[dir].cachehint =
IPSEC_PCBHINT_NO;
break;
default:
pcbsp->sp_cache[dir].cachehint =
IPSEC_PCBHINT_YES;
}
}
}
pcbsp->sp_cache[dir].cachegen = ipsec_spdgen;
return 0;
}
static int
ipsec_invalpcbcache(struct inpcbpolicy *pcbsp, int dir)
{
int i;
for (i = IPSEC_DIR_INBOUND; i <= IPSEC_DIR_OUTBOUND; i++) {
if (dir != IPSEC_DIR_ANY && i != dir)
continue;
if (pcbsp->sp_cache[i].cachesp)
KEY_FREESP(&pcbsp->sp_cache[i].cachesp);
pcbsp->sp_cache[i].cachesp = NULL;
pcbsp->sp_cache[i].cachehint = IPSEC_PCBHINT_MAYBE;
pcbsp->sp_cache[i].cachegen = 0;
memset(&pcbsp->sp_cache[i].cacheidx, 0,
sizeof(pcbsp->sp_cache[i].cacheidx));
}
return 0;
}
void
ipsec_pcbconn(struct inpcbpolicy *pcbsp)
{
pcbsp->sp_cacheflags |= IPSEC_PCBSP_CONNECTED;
ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY);
}
void
ipsec_pcbdisconn(struct inpcbpolicy *pcbsp)
{
pcbsp->sp_cacheflags &= ~IPSEC_PCBSP_CONNECTED;
ipsec_invalpcbcache(pcbsp, IPSEC_DIR_ANY);
}
void
ipsec_invalpcbcacheall(void)
{
if (ipsec_spdgen == UINT_MAX)
ipsec_spdgen = 1;
else
ipsec_spdgen++;
}
#endif /* __NetBSD__ */
/*
* Return a held reference to the default SP.
*/
static struct secpolicy *
key_allocsp_default(int af, const char *where, int tag)
{
struct secpolicy *sp;
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP %s from %s:%u\n", __func__, where, tag));
switch(af) {
case AF_INET:
sp = &ip4_def_policy;
break;
#ifdef INET6
case AF_INET6:
sp = &ip6_def_policy;
break;
#endif
default:
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("%s: unexpected protocol family %u\n", __func__,
af));
return NULL;
}
if (sp->policy != IPSEC_POLICY_DISCARD &&
sp->policy != IPSEC_POLICY_NONE) {
ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
sp->policy, IPSEC_POLICY_NONE));
sp->policy = IPSEC_POLICY_NONE;
}
sp->refcnt++;
KEYDEBUG(KEYDEBUG_IPSEC_STAMP, printf("DP %s returns SP:%p (%u)\n",
__func__, sp, sp->refcnt));
return sp;
}
#define KEY_ALLOCSP_DEFAULT(af) \
key_allocsp_default((af),__FILE__, __LINE__)
/*
* For OUTBOUND packet having a socket. Searching SPD for packet,
* and return a pointer to SP.
* OUT: NULL: no apropreate SP found, the following value is set to error.
* 0 : bypass
* EACCES : discard packet.
* ENOENT : ipsec_acquire() in progress, maybe.
* others : error occurred.
* others: a pointer to SP
*
* NOTE: IPv6 mapped address concern is implemented here.
*/
struct secpolicy *
ipsec_getpolicy(const struct tdb_ident *tdbi, u_int dir)
{
struct secpolicy *sp;
IPSEC_ASSERT(tdbi != NULL, ("%s: null tdbi", __func__));
IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
("%s: invalid direction %u", __func__, dir));
sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
if (sp == NULL) /*XXX????*/
sp = KEY_ALLOCSP_DEFAULT(tdbi->dst.sa.sa_family);
IPSEC_ASSERT(sp != NULL, ("%s: null SP", __func__));
return sp;
}
/*
* For OUTBOUND packet having a socket. Searching SPD for packet,
* and return a pointer to SP.
* OUT: NULL: no apropreate SP found, the following value is set to error.
* 0 : bypass
* EACCES : discard packet.
* ENOENT : ipsec_acquire() in progress, maybe.
* others : error occurred.
* others: a pointer to SP
*
* NOTE: IPv6 mapped address concern is implemented here.
*/
static struct secpolicy *
ipsec_getpolicybysock(struct mbuf *m, u_int dir, PCB_T *inp, int *error)
{
struct inpcbpolicy *pcbsp = NULL;
struct secpolicy *currsp = NULL; /* policy on socket */
struct secpolicy *sp;
int af;
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
IPSEC_ASSERT(inp != NULL, ("%s: null inpcb", __func__));
IPSEC_ASSERT(error != NULL, ("%s: null error", __func__));
IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
("%s: invalid direction %u", __func__, dir));
IPSEC_ASSERT(PCB_SOCKET(inp) != NULL, ("%s: null socket", __func__));
/* XXX FIXME inpcb/in6pcb vs socket*/
af = PCB_FAMILY(inp);
IPSEC_ASSERT(af == AF_INET || af == AF_INET6,
("%s: unexpected protocol family %u", __func__, af));
#ifdef __NetBSD__
IPSEC_ASSERT(inp->inph_sp != NULL, ("null PCB policy cache"));
/* If we have a cached entry, and if it is still valid, use it. */
IPSEC_STATINC(IPSEC_STAT_SPDCACHELOOKUP);
currsp = ipsec_checkpcbcache(m, /*inpcb_hdr*/inp->inph_sp, dir);
if (currsp) {
*error = 0;
return currsp;
}
IPSEC_STATINC(IPSEC_STAT_SPDCACHEMISS);
#endif /* __NetBSD__ */
switch (af) {
case AF_INET: {
struct inpcb *in4p = PCB_TO_IN4PCB(inp);
/* set spidx in pcb */
*error = ipsec4_setspidx_inpcb(m, in4p);
pcbsp = in4p->inp_sp;
break;
}
#if defined(INET6)
case AF_INET6: {
struct in6pcb *in6p = PCB_TO_IN6PCB(inp);
/* set spidx in pcb */
*error = ipsec6_setspidx_in6pcb(m, in6p);
pcbsp = in6p->in6p_sp;
break;
}
#endif
default:
*error = EPFNOSUPPORT;
break;
}
if (*error)
return NULL;
IPSEC_ASSERT(pcbsp != NULL, ("%s: null pcbsp", __func__));
switch (dir) {
case IPSEC_DIR_INBOUND:
currsp = pcbsp->sp_in;
break;
case IPSEC_DIR_OUTBOUND:
currsp = pcbsp->sp_out;
break;
}
IPSEC_ASSERT(currsp != NULL, ("%s: null currsp", __func__));
if (pcbsp->priv) { /* when privilieged socket */
switch (currsp->policy) {
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_IPSEC:
currsp->refcnt++;
sp = currsp;
break;
case IPSEC_POLICY_ENTRUST:
/* look for a policy in SPD */
sp = KEY_ALLOCSP(&currsp->spidx, dir);
if (sp == NULL) /* no SP found */
sp = KEY_ALLOCSP_DEFAULT(af);
break;
default:
ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
__func__, currsp->policy));
*error = EINVAL;
return NULL;
}
} else { /* unpriv, SPD has policy */
sp = KEY_ALLOCSP(&currsp->spidx, dir);
if (sp == NULL) { /* no SP found */
switch (currsp->policy) {
case IPSEC_POLICY_BYPASS:
ipseclog((LOG_ERR, "%s: Illegal policy for "
"non-priviliged defined %d\n", __func__,
currsp->policy));
*error = EINVAL;
return NULL;
case IPSEC_POLICY_ENTRUST:
sp = KEY_ALLOCSP_DEFAULT(af);
break;
case IPSEC_POLICY_IPSEC:
currsp->refcnt++;
sp = currsp;
break;
default:
ipseclog((LOG_ERR, "%s: Invalid policy for "
"PCB %d\n", __func__, currsp->policy));
*error = EINVAL;
return NULL;
}
}
}
IPSEC_ASSERT(sp != NULL,
("%s: null SP (priv %u policy %u", __func__, pcbsp->priv,
currsp->policy));
KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
printf("DP %s (priv %u policy %u) allocates SP:%p (refcnt %u)\n",
__func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
#ifdef __NetBSD__
ipsec_fillpcbcache(pcbsp, m, sp, dir);
#endif /* __NetBSD__ */
return sp;
}
/*
* For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
* and return a pointer to SP.
* OUT: positive: a pointer to the entry for security policy leaf matched.
* NULL: no apropreate SP found, the following value is set to error.
* 0 : bypass
* EACCES : discard packet.
* ENOENT : ipsec_acquire() in progress, maybe.
* others : error occurred.
*/
struct secpolicy *
ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error)
{
struct secpolicyindex spidx;
struct secpolicy *sp;
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
IPSEC_ASSERT(error != NULL, ("%s: null error", __func__));
IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
("%s: invalid direction %u", __func__, dir));
sp = NULL;
/* Make an index to look for a policy. */
*error = ipsec_setspidx(m, &spidx, (flag & IP_FORWARDING) ? 0 : 1);
if (*error != 0) {
DPRINTF(("%s: setpidx failed, dir %u flag %u\n", __func__,
dir, flag));
memset(&spidx, 0, sizeof (spidx));
return NULL;
}
spidx.dir = dir;
if (key_havesp(dir)) {
sp = KEY_ALLOCSP(&spidx, dir);
}
if (sp == NULL) /* no SP found, use system default */
sp = KEY_ALLOCSP_DEFAULT(spidx.dst.sa.sa_family);
IPSEC_ASSERT(sp != NULL, ("%s: null SP", __func__));
return sp;
}
struct secpolicy *
ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
struct inpcb *inp)
{
struct secpolicy *sp;
*error = 0;
/* XXX KAME IPv6 calls us with non-null inp but bogus inp_socket? */
if (inp == NULL || inp->inp_socket == NULL) {
sp = ipsec_getpolicybyaddr(m, dir, flag, error);
} else
sp = ipsec_getpolicybysock(m, dir, IN4PCB_TO_PCB(inp), error);
if (sp == NULL) {
IPSEC_ASSERT(*error != 0,
("%s: getpolicy failed w/o error", __func__));
IPSEC_STATINC(IPSEC_STAT_OUT_INVAL);
return NULL;
}
IPSEC_ASSERT(*error == 0, ("%s: sp w/ error set to %u", __func__,
*error));
switch (sp->policy) {
case IPSEC_POLICY_ENTRUST:
default:
printf("%s: invalid policy %u\n", __func__, sp->policy);
/* fall thru... */
case IPSEC_POLICY_DISCARD:
IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO);
*error = -EINVAL; /* packet is discarded by caller */
break;
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
KEY_FREESP(&sp);
sp = NULL; /* NB: force NULL result */
break;
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) /* acquire an SA */
*error = key_spdacquire(sp);
break;
}
if (*error != 0) {
KEY_FREESP(&sp);
sp = NULL;
DPRINTF(("%s: done, error %d\n", __func__, *error));
}
return sp;
}
int
ipsec4_output(struct mbuf *m, struct socket *so, int flags,
struct secpolicy **sp_out, u_long *mtu, bool *natt_frag, bool *done)
{
const struct ip *ip = mtod(m, const struct ip *);
struct secpolicy *sp = NULL;
struct inpcb *inp;
int error, s;
inp = (so && so->so_proto->pr_domain->dom_family == AF_INET) ?
(struct inpcb *)so->so_pcb : NULL;
/*
* Check the security policy (SP) for the packet and, if required,
* do IPsec-related processing. There are two cases here; the first
* time a packet is sent through it will be untagged and handled by
* ipsec4_checkpolicy(). If the packet is resubmitted to ip_output
* (e.g. after AH, ESP, etc. processing), there will be a tag to
* bypass the lookup and related policy checking.
*/
if (ipsec_outdone(m)) {
return 0;
}
s = splsoftnet();
if (inp && IPSEC_PCB_SKIP_IPSEC(inp->inp_sp, IPSEC_DIR_OUTBOUND)) {
splx(s);
return 0;
}
sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, inp);
/*
* There are four return cases:
* sp != NULL apply IPsec policy
* sp == NULL, error == 0 no IPsec handling needed
* sp == NULL, error == -EINVAL discard packet w/o error
* sp == NULL, error != 0 discard packet, report error
*/
if (sp == NULL) {
splx(s);
if (error) {
/*
* Hack: -EINVAL is used to signal that a packet
* should be silently discarded. This is typically
* because we asked key management for an SA and
* it was delayed (e.g. kicked up to IKE).
*/
if (error == -EINVAL)
error = 0;
m_freem(m);
*done = true;
return error;
}
/* No IPsec processing for this packet. */
return 0;
}
*sp_out = sp;
/*
* NAT-T ESP fragmentation: do not do IPSec processing now,
* we will do it on each fragmented packet.
*/
if (sp->req->sav && (sp->req->sav->natt_type &
(UDP_ENCAP_ESPINUDP|UDP_ENCAP_ESPINUDP_NON_IKE))) {
if (ntohs(ip->ip_len) > sp->req->sav->esp_frag) {
*mtu = sp->req->sav->esp_frag;
*natt_frag = true;
splx(s);
return 0;
}
}
/*
* Do delayed checksums now because we send before
* this is done in the normal processing path.
*/
if (m->m_pkthdr.csum_flags & (M_CSUM_TCPv4|M_CSUM_UDPv4)) {
in_delayed_cksum(m);
m->m_pkthdr.csum_flags &= ~(M_CSUM_TCPv4|M_CSUM_UDPv4);
}
/* Note: callee frees mbuf */
error = ipsec4_process_packet(m, sp->req, flags, 0);
/*
* Preserve KAME behaviour: ENOENT can be returned
* when an SA acquire is in progress. Don't propagate
* this to user-level; it confuses applications.
*
* XXX this will go away when the SADB is redone.
*/
if (error == ENOENT)
error = 0;
splx(s);
*done = true;
return error;
}
int
ipsec4_input(struct mbuf *m, int flags)
{
struct m_tag *mtag;
struct tdb_ident *tdbi;
struct secpolicy *sp;
int error, s;
/*
* Check if the packet has already had IPsec processing done.
* If so, then just pass it along. This tag gets set during AH,
* ESP, etc. input handling, before the packet is returned to
* the IP input queue for delivery.
*/
mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
s = splsoftnet();
if (mtag != NULL) {
tdbi = (struct tdb_ident *)(mtag + 1);
sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
} else {
sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
IP_FORWARDING, &error);
}
if (sp == NULL) {
splx(s);
return EINVAL;
}
/*
* Check security policy against packet attributes.
*/
error = ipsec_in_reject(sp, m);
KEY_FREESP(&sp);
splx(s);
if (error) {
return error;
}
if (flags == 0) {
/* We are done. */
return 0;
}
/*
* Peek at the outbound SP for this packet to determine if
* it is a Fast Forward candidate.
*/
mtag = m_tag_find(m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
if (mtag != NULL) {
m->m_flags &= ~M_CANFASTFWD;
return 0;
}
s = splsoftnet();
sp = ipsec4_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error, NULL);
if (sp != NULL) {
m->m_flags &= ~M_CANFASTFWD;
KEY_FREESP(&sp);
}
splx(s);
return 0;
}
int
ipsec4_forward(struct mbuf *m, int *destmtu)
{
/*
* If the packet is routed over IPsec tunnel, tell the
* originator the tunnel MTU.
* tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
* XXX quickhack!!!
*/
struct secpolicy *sp;
size_t ipsechdr;
int error;
sp = ipsec4_getpolicybyaddr(m,
IPSEC_DIR_OUTBOUND, IP_FORWARDING, &error);
if (sp == NULL) {
return EINVAL;
}
/* Count IPsec header size. */
ipsechdr = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL);
/*
* Find the correct route for outer IPv4 header, compute tunnel MTU.
*/
if (sp->req && sp->req->sav && sp->req->sav->sah) {
struct route *ro;
struct rtentry *rt;
ro = &sp->req->sav->sah->sa_route;
rt = rtcache_validate(ro);
if (rt && rt->rt_ifp) {
*destmtu = rt->rt_rmx.rmx_mtu ?
rt->rt_rmx.rmx_mtu : rt->rt_ifp->if_mtu;
*destmtu -= ipsechdr;
}
}
KEY_FREESP(&sp);
return 0;
}
#ifdef INET6
struct secpolicy *
ipsec6_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
struct in6pcb *in6p)
{
struct secpolicy *sp;
*error = 0;
/* XXX KAME IPv6 calls us with non-null inp but bogus inp_socket? */
if (in6p == NULL || in6p->in6p_socket == NULL) {
sp = ipsec_getpolicybyaddr(m, dir, flag, error);
} else
sp = ipsec_getpolicybysock(m, dir, IN6PCB_TO_PCB(in6p), error);
if (sp == NULL) {
IPSEC_ASSERT(*error != 0, ("%s: getpolicy failed w/o error",
__func__));
IPSEC_STATINC(IPSEC_STAT_OUT_INVAL);
return NULL;
}
IPSEC_ASSERT(*error == 0, ("%s: sp w/ error set to %u", __func__,
*error));
switch (sp->policy) {
case IPSEC_POLICY_ENTRUST:
default:
printf("%s: invalid policy %u\n", __func__, sp->policy);
/* fall thru... */
case IPSEC_POLICY_DISCARD:
IPSEC_STATINC(IPSEC_STAT_OUT_POLVIO);
*error = -EINVAL; /* packet is discarded by caller */
break;
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
KEY_FREESP(&sp);
sp = NULL; /* NB: force NULL result */
break;
case IPSEC_POLICY_IPSEC:
if (sp->req == NULL) /* acquire an SA */
*error = key_spdacquire(sp);
break;
}
if (*error != 0) {
KEY_FREESP(&sp);
sp = NULL;
DPRINTF(("%s: done, error %d\n", __func__, *error));
}
return sp;
}
#endif /* INET6 */
static int
ipsec4_setspidx_inpcb(struct mbuf *m, struct inpcb *pcb)
{
int error;
IPSEC_ASSERT(pcb != NULL, ("%s: null pcb", __func__));
IPSEC_ASSERT(pcb->inp_sp != NULL, ("%s: null inp_sp", __func__));
IPSEC_ASSERT(pcb->inp_sp->sp_out != NULL && pcb->inp_sp->sp_in != NULL,
("%s: null sp_in || sp_out", __func__));
error = ipsec_setspidx(m, &pcb->inp_sp->sp_in->spidx, 1);
if (error == 0) {
pcb->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
pcb->inp_sp->sp_out->spidx = pcb->inp_sp->sp_in->spidx;
pcb->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
} else {
memset(&pcb->inp_sp->sp_in->spidx, 0,
sizeof (pcb->inp_sp->sp_in->spidx));
memset(&pcb->inp_sp->sp_out->spidx, 0,
sizeof (pcb->inp_sp->sp_in->spidx));
}
return error;
}
#ifdef INET6
static int
ipsec6_setspidx_in6pcb(struct mbuf *m, struct in6pcb *pcb)
{
struct secpolicyindex *spidx;
int error;
IPSEC_ASSERT(pcb != NULL, ("%s: null pcb", __func__));
IPSEC_ASSERT(pcb->in6p_sp != NULL, ("%s: null inp_sp", __func__));
IPSEC_ASSERT(pcb->in6p_sp->sp_out != NULL &&
pcb->in6p_sp->sp_in != NULL, ("%s: null sp_in || sp_out",
__func__));
memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx));
memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx));
spidx = &pcb->in6p_sp->sp_in->spidx;
error = ipsec_setspidx(m, spidx, 1);
if (error)
goto bad;
spidx->dir = IPSEC_DIR_INBOUND;
spidx = &pcb->in6p_sp->sp_out->spidx;
error = ipsec_setspidx(m, spidx, 1);
if (error)
goto bad;
spidx->dir = IPSEC_DIR_OUTBOUND;
return 0;
bad:
memset(&pcb->in6p_sp->sp_in->spidx, 0, sizeof(*spidx));
memset(&pcb->in6p_sp->sp_out->spidx, 0, sizeof(*spidx));
return error;
}
#endif
/*
* configure security policy index (src/dst/proto/sport/dport)
* by looking at the content of mbuf.
* the caller is responsible for error recovery (like clearing up spidx).
*/
static int
ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
{
struct ip *ip = NULL;
struct ip ipbuf;
u_int v;
struct mbuf *n;
int len;
int error;
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
/*
* validate m->m_pkthdr.len. we see incorrect length if we
* mistakenly call this function with inconsistent mbuf chain
* (like 4.4BSD tcp/udp processing). XXX should we panic here?
*/
len = 0;
for (n = m; n; n = n->m_next)
len += n->m_len;
if (m->m_pkthdr.len != len) {
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: total of m_len(%d) "
"!= pkthdr.len(%d), ignored.\n", __func__, len,
m->m_pkthdr.len));
return EINVAL;
}
if (m->m_pkthdr.len < sizeof(struct ip)) {
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: pkthdr.len(%d) < "
"sizeof(struct ip), ignored.\n", __func__,
m->m_pkthdr.len));
return EINVAL;
}
if (m->m_len >= sizeof(*ip))
ip = mtod(m, struct ip *);
else {
m_copydata(m, 0, sizeof(ipbuf), &ipbuf);
ip = &ipbuf;
}
v = ip->ip_v;
switch (v) {
case 4:
error = ipsec4_setspidx_ipaddr(m, spidx);
if (error)
return error;
ipsec4_get_ulp(m, spidx, needport);
return 0;
#ifdef INET6
case 6:
if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: "
"pkthdr.len(%d) < sizeof(struct ip6_hdr), "
"ignored.\n", __func__, m->m_pkthdr.len));
return EINVAL;
}
error = ipsec6_setspidx_ipaddr(m, spidx);
if (error)
return error;
ipsec6_get_ulp(m, spidx, needport);
return 0;
#endif
default:
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: unknown IP version "
"%u, ignored.\n", __func__, v));
return EINVAL;
}
}
static void
ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
{
u_int8_t nxt;
int off;
/* sanity check */
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),
("%s: packet too short", __func__));
/* NB: ip_input() flips it into host endian XXX need more checking */
if (m->m_len >= sizeof(struct ip)) {
struct ip *ip = mtod(m, struct ip *);
if (ip->ip_off & IP_OFF_CONVERT(IP_MF | IP_OFFMASK))
goto done;
off = ip->ip_hl << 2;
nxt = ip->ip_p;
} else {
struct ip ih;
m_copydata(m, 0, sizeof (struct ip), &ih);
if (ih.ip_off & IP_OFF_CONVERT(IP_MF | IP_OFFMASK))
goto done;
off = ih.ip_hl << 2;
nxt = ih.ip_p;
}
while (off < m->m_pkthdr.len) {
struct ip6_ext ip6e;
struct tcphdr th;
struct udphdr uh;
struct icmp icmph;
switch (nxt) {
case IPPROTO_TCP:
spidx->ul_proto = nxt;
if (!needport)
goto done_proto;
if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
goto done;
m_copydata(m, off, sizeof (th), &th);
spidx->src.sin.sin_port = th.th_sport;
spidx->dst.sin.sin_port = th.th_dport;
return;
case IPPROTO_UDP:
spidx->ul_proto = nxt;
if (!needport)
goto done_proto;
if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
goto done;
m_copydata(m, off, sizeof (uh), &uh);
spidx->src.sin.sin_port = uh.uh_sport;
spidx->dst.sin.sin_port = uh.uh_dport;
return;
case IPPROTO_AH:
if (m->m_pkthdr.len > off + sizeof(ip6e))
goto done;
/* XXX sigh, this works but is totally bogus */
m_copydata(m, off, sizeof(ip6e), &ip6e);
off += (ip6e.ip6e_len + 2) << 2;
nxt = ip6e.ip6e_nxt;
break;
case IPPROTO_ICMP:
spidx->ul_proto = nxt;
if (off + sizeof(struct icmp) > m->m_pkthdr.len)
return;
m_copydata(m, off, sizeof(icmph), &icmph);
((struct sockaddr_in *)&spidx->src)->sin_port =
htons((uint16_t)icmph.icmp_type);
((struct sockaddr_in *)&spidx->dst)->sin_port =
htons((uint16_t)icmph.icmp_code);
return;
default:
/* XXX intermediate headers??? */
spidx->ul_proto = nxt;
goto done_proto;
}
}
done:
spidx->ul_proto = IPSEC_ULPROTO_ANY;
done_proto:
spidx->src.sin.sin_port = IPSEC_PORT_ANY;
spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
}
/* assumes that m is sane */
static int
ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
{
static const struct sockaddr_in template = {
sizeof (struct sockaddr_in),
AF_INET,
0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
};
spidx->src.sin = template;
spidx->dst.sin = template;
if (m->m_len < sizeof (struct ip)) {
m_copydata(m, offsetof(struct ip, ip_src),
sizeof (struct in_addr),
&spidx->src.sin.sin_addr);
m_copydata(m, offsetof(struct ip, ip_dst),
sizeof (struct in_addr),
&spidx->dst.sin.sin_addr);
} else {
struct ip *ip = mtod(m, struct ip *);
spidx->src.sin.sin_addr = ip->ip_src;
spidx->dst.sin.sin_addr = ip->ip_dst;
}
spidx->prefs = sizeof(struct in_addr) << 3;
spidx->prefd = sizeof(struct in_addr) << 3;
return 0;
}
#ifdef INET6
static void
ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx,
int needport)
{
int off, nxt;
struct tcphdr th;
struct udphdr uh;
struct icmp6_hdr icmph;
/* sanity check */
if (m == NULL)
panic("%s: NULL pointer was passed", __func__);
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s:\n", __func__);
kdebug_mbuf(m));
/* set default */
spidx->ul_proto = IPSEC_ULPROTO_ANY;
((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
nxt = -1;
off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
if (off < 0 || m->m_pkthdr.len < off)
return;
switch (nxt) {
case IPPROTO_TCP:
spidx->ul_proto = nxt;
if (!needport)
break;
if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
break;
m_copydata(m, off, sizeof(th), &th);
((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
break;
case IPPROTO_UDP:
spidx->ul_proto = nxt;
if (!needport)
break;
if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
break;
m_copydata(m, off, sizeof(uh), &uh);
((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
break;
case IPPROTO_ICMPV6:
spidx->ul_proto = nxt;
if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
break;
m_copydata(m, off, sizeof(icmph), &icmph);
((struct sockaddr_in6 *)&spidx->src)->sin6_port =
htons((uint16_t)icmph.icmp6_type);
((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
htons((uint16_t)icmph.icmp6_code);
break;
default:
/* XXX intermediate headers??? */
spidx->ul_proto = nxt;
break;
}
}
/* assumes that m is sane */
static int
ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
{
struct ip6_hdr *ip6 = NULL;
struct ip6_hdr ip6buf;
struct sockaddr_in6 *sin6;
if (m->m_len >= sizeof(*ip6))
ip6 = mtod(m, struct ip6_hdr *);
else {
m_copydata(m, 0, sizeof(ip6buf), &ip6buf);
ip6 = &ip6buf;
}
sin6 = (struct sockaddr_in6 *)&spidx->src;
memset(sin6, 0, sizeof(*sin6));
sin6->sin6_family = AF_INET6;
sin6->sin6_len = sizeof(struct sockaddr_in6);
memcpy(&sin6->sin6_addr, &ip6->ip6_src, sizeof(ip6->ip6_src));
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
sin6->sin6_addr.s6_addr16[1] = 0;
sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
}
spidx->prefs = sizeof(struct in6_addr) << 3;
sin6 = (struct sockaddr_in6 *)&spidx->dst;
memset(sin6, 0, sizeof(*sin6));
sin6->sin6_family = AF_INET6;
sin6->sin6_len = sizeof(struct sockaddr_in6);
memcpy(&sin6->sin6_addr, &ip6->ip6_dst, sizeof(ip6->ip6_dst));
if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
sin6->sin6_addr.s6_addr16[1] = 0;
sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
}
spidx->prefd = sizeof(struct in6_addr) << 3;
return 0;
}
#endif
static void
ipsec_delpcbpolicy(struct inpcbpolicy *p)
{
free(p, M_SECA);
}
/* initialize policy in PCB */
int
ipsec_init_policy(struct socket *so, struct inpcbpolicy **policy)
{
struct inpcbpolicy *new;
/* sanity check. */
if (so == NULL || policy == NULL)
panic("%s: NULL pointer was passed", __func__);
new = malloc(sizeof(*new), M_SECA, M_NOWAIT|M_ZERO);
if (new == NULL) {
ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
return ENOBUFS;
}
if (IPSEC_PRIVILEGED_SO(so))
new->priv = 1;
else
new->priv = 0;
if ((new->sp_in = KEY_NEWSP()) == NULL) {
ipsec_delpcbpolicy(new);
return ENOBUFS;
}
new->sp_in->state = IPSEC_SPSTATE_ALIVE;
new->sp_in->policy = IPSEC_POLICY_ENTRUST;
if ((new->sp_out = KEY_NEWSP()) == NULL) {
KEY_FREESP(&new->sp_in);
ipsec_delpcbpolicy(new);
return ENOBUFS;
}
new->sp_out->state = IPSEC_SPSTATE_ALIVE;
new->sp_out->policy = IPSEC_POLICY_ENTRUST;
*policy = new;
return 0;
}
/* copy old ipsec policy into new */
int
ipsec_copy_policy(const struct inpcbpolicy *old, struct inpcbpolicy *new)
{
struct secpolicy *sp;
sp = ipsec_deepcopy_policy(old->sp_in);
if (sp) {
KEY_FREESP(&new->sp_in);
new->sp_in = sp;
} else
return ENOBUFS;
sp = ipsec_deepcopy_policy(old->sp_out);
if (sp) {
KEY_FREESP(&new->sp_out);
new->sp_out = sp;
} else
return ENOBUFS;
new->priv = old->priv;
return 0;
}
/* deep-copy a policy in PCB */
static struct secpolicy *
ipsec_deepcopy_policy(const struct secpolicy *src)
{
struct ipsecrequest *newchain = NULL;
const struct ipsecrequest *p;
struct ipsecrequest **q;
struct ipsecrequest *r;
struct secpolicy *dst;
if (src == NULL)
return NULL;
dst = KEY_NEWSP();
if (dst == NULL)
return NULL;
/*
* deep-copy IPsec request chain. This is required since struct
* ipsecrequest is not reference counted.
*/
q = &newchain;
for (p = src->req; p; p = p->next) {
*q = malloc(sizeof(**q), M_SECA, M_NOWAIT|M_ZERO);
if (*q == NULL)
goto fail;
(*q)->next = NULL;
(*q)->saidx.proto = p->saidx.proto;
(*q)->saidx.mode = p->saidx.mode;
(*q)->level = p->level;
(*q)->saidx.reqid = p->saidx.reqid;
memcpy(&(*q)->saidx.src, &p->saidx.src, sizeof((*q)->saidx.src));
memcpy(&(*q)->saidx.dst, &p->saidx.dst, sizeof((*q)->saidx.dst));
(*q)->sav = NULL;
(*q)->sp = dst;
q = &((*q)->next);
}
dst->req = newchain;
dst->state = src->state;
dst->policy = src->policy;
/* do not touch the refcnt fields */
return dst;
fail:
for (q = &newchain; *q; q = &r) {
r = (*q)->next;
free(*q, M_SECA);
}
return NULL;
}
/* set policy and ipsec request if present. */
static int
ipsec_set_policy(
struct secpolicy **policy,
int optname,
const void *request,
size_t len,
kauth_cred_t cred
)
{
const struct sadb_x_policy *xpl;
struct secpolicy *newsp = NULL;
int error;
/* sanity check. */
if (policy == NULL || *policy == NULL || request == NULL)
return EINVAL;
if (len < sizeof(*xpl))
return EINVAL;
xpl = (const struct sadb_x_policy *)request;
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: passed policy\n", __func__);
kdebug_sadb_x_policy((const struct sadb_ext *)xpl));
/* check policy type */
/* ipsec_set_policy() accepts IPSEC, ENTRUST and BYPASS. */
if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
|| xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
return EINVAL;
/* check privileged socket */
if (xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
error = kauth_authorize_network(cred, KAUTH_NETWORK_IPSEC,
KAUTH_REQ_NETWORK_IPSEC_BYPASS, NULL, NULL, NULL);
if (error)
return (error);
}
/* allocation new SP entry */
if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
return error;
newsp->state = IPSEC_SPSTATE_ALIVE;
/* clear old SP and set new SP */
KEY_FREESP(policy);
*policy = newsp;
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s: new policy\n", __func__);
kdebug_secpolicy(newsp));
return 0;
}
static int
ipsec_get_policy(struct secpolicy *policy, struct mbuf **mp)
{
/* sanity check. */
if (policy == NULL || mp == NULL)
return EINVAL;
*mp = key_sp2msg(policy);
if (!*mp) {
ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
return ENOBUFS;
}
(*mp)->m_type = MT_DATA;
KEYDEBUG(KEYDEBUG_IPSEC_DUMP, printf("%s:\n", __func__);
kdebug_mbuf(*mp));
return 0;
}
int
ipsec4_set_policy(struct inpcb *inp, int optname, const void *request,
size_t len, kauth_cred_t cred)
{
const struct sadb_x_policy *xpl;
struct secpolicy **policy;
/* sanity check. */
if (inp == NULL || request == NULL)
return EINVAL;
if (len < sizeof(*xpl))
return EINVAL;
xpl = (const struct sadb_x_policy *)request;
IPSEC_ASSERT(inp->inp_sp != NULL, ("%s: null inp->in_sp", __func__));
/* select direction */
switch (xpl->sadb_x_policy_dir) {
case IPSEC_DIR_INBOUND:
policy = &inp->inp_sp->sp_in;
break;
case IPSEC_DIR_OUTBOUND:
policy = &inp->inp_sp->sp_out;
break;
default:
ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
xpl->sadb_x_policy_dir));
return EINVAL;
}
return ipsec_set_policy(policy, optname, request, len, cred);
}
int
ipsec4_get_policy(struct inpcb *inp, const void *request, size_t len,
struct mbuf **mp)
{
const struct sadb_x_policy *xpl;
struct secpolicy *policy;
/* sanity check. */
if (inp == NULL || request == NULL || mp == NULL)
return EINVAL;
IPSEC_ASSERT(inp->inp_sp != NULL, ("%s: null inp_sp", __func__));
if (len < sizeof(*xpl))
return EINVAL;
xpl = (const struct sadb_x_policy *)request;
/* select direction */
switch (xpl->sadb_x_policy_dir) {
case IPSEC_DIR_INBOUND:
policy = inp->inp_sp->sp_in;
break;
case IPSEC_DIR_OUTBOUND:
policy = inp->inp_sp->sp_out;
break;
default:
ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
xpl->sadb_x_policy_dir));
return EINVAL;
}
return ipsec_get_policy(policy, mp);
}
/* delete policy in PCB */
int
ipsec4_delete_pcbpolicy(struct inpcb *inp)
{
IPSEC_ASSERT(inp != NULL, ("%s: null inp", __func__));
if (inp->inp_sp == NULL)
return 0;
if (inp->inp_sp->sp_in != NULL)
KEY_FREESP(&inp->inp_sp->sp_in);
if (inp->inp_sp->sp_out != NULL)
KEY_FREESP(&inp->inp_sp->sp_out);
#ifdef __NetBSD__
ipsec_invalpcbcache(inp->inp_sp, IPSEC_DIR_ANY);
#endif
ipsec_delpcbpolicy(inp->inp_sp);
inp->inp_sp = NULL;
return 0;
}
#ifdef INET6
int
ipsec6_set_policy(struct in6pcb *in6p, int optname, const void *request,
size_t len, kauth_cred_t cred)
{
const struct sadb_x_policy *xpl;
struct secpolicy **policy;
/* sanity check. */
if (in6p == NULL || request == NULL)
return EINVAL;
if (len < sizeof(*xpl))
return EINVAL;
xpl = (const struct sadb_x_policy *)request;
/* select direction */
switch (xpl->sadb_x_policy_dir) {
case IPSEC_DIR_INBOUND:
policy = &in6p->in6p_sp->sp_in;
break;
case IPSEC_DIR_OUTBOUND:
policy = &in6p->in6p_sp->sp_out;
break;
default:
ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
xpl->sadb_x_policy_dir));
return EINVAL;
}
return ipsec_set_policy(policy, optname, request, len, cred);
}
int
ipsec6_get_policy(struct in6pcb *in6p, const void *request, size_t len,
struct mbuf **mp)
{
const struct sadb_x_policy *xpl;
struct secpolicy *policy;
/* sanity check. */
if (in6p == NULL || request == NULL || mp == NULL)
return EINVAL;
IPSEC_ASSERT(in6p->in6p_sp != NULL, ("%s: null in6p_sp", __func__));
if (len < sizeof(*xpl))
return EINVAL;
xpl = (const struct sadb_x_policy *)request;
/* select direction */
switch (xpl->sadb_x_policy_dir) {
case IPSEC_DIR_INBOUND:
policy = in6p->in6p_sp->sp_in;
break;
case IPSEC_DIR_OUTBOUND:
policy = in6p->in6p_sp->sp_out;
break;
default:
ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
xpl->sadb_x_policy_dir));
return EINVAL;
}
return ipsec_get_policy(policy, mp);
}
int
ipsec6_delete_pcbpolicy(struct in6pcb *in6p)
{
IPSEC_ASSERT(in6p != NULL, ("%s: null in6p", __func__));
if (in6p->in6p_sp == NULL)
return 0;
if (in6p->in6p_sp->sp_in != NULL)
KEY_FREESP(&in6p->in6p_sp->sp_in);
if (in6p->in6p_sp->sp_out != NULL)
KEY_FREESP(&in6p->in6p_sp->sp_out);
#ifdef __NetBSD
ipsec_invalpcbcache(in6p->in6p_sp, IPSEC_DIR_ANY);
#endif
ipsec_delpcbpolicy(in6p->in6p_sp);
in6p->in6p_sp = NULL;
return 0;
}
#endif
/*
* return current level.
* Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
*/
u_int
ipsec_get_reqlevel(const struct ipsecrequest *isr)
{
u_int level = 0;
u_int esp_trans_deflev, esp_net_deflev;
u_int ah_trans_deflev, ah_net_deflev;
IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("%s: null argument",
__func__));
IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family ==
isr->sp->spidx.dst.sa.sa_family,
("%s: af family mismatch, src %u, dst %u", __func__,
isr->sp->spidx.src.sa.sa_family, isr->sp->spidx.dst.sa.sa_family));
/* XXX note that we have ipseclog() expanded here - code sync issue */
#define IPSEC_CHECK_DEFAULT(lev) \
(((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
&& (lev) != IPSEC_LEVEL_UNIQUE) ? \
(ipsec_debug ? log(LOG_INFO, "fixed system default level " #lev \
":%d->%d\n", (lev), IPSEC_LEVEL_REQUIRE) : (void)0), \
(lev) = IPSEC_LEVEL_REQUIRE, (lev) \
: (lev))
/* set default level */
switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
#ifdef INET
case AF_INET:
esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_trans_deflev);
esp_net_deflev = IPSEC_CHECK_DEFAULT(ip4_esp_net_deflev);
ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_trans_deflev);
ah_net_deflev = IPSEC_CHECK_DEFAULT(ip4_ah_net_deflev);
break;
#endif
#ifdef INET6
case AF_INET6:
esp_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_trans_deflev);
esp_net_deflev = IPSEC_CHECK_DEFAULT(ip6_esp_net_deflev);
ah_trans_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_trans_deflev);
ah_net_deflev = IPSEC_CHECK_DEFAULT(ip6_ah_net_deflev);
break;
#endif /* INET6 */
default:
panic("%s: unknown af %u", __func__,
isr->sp->spidx.src.sa.sa_family);
}
#undef IPSEC_CHECK_DEFAULT
/* set level */
switch (isr->level) {
case IPSEC_LEVEL_DEFAULT:
switch (isr->saidx.proto) {
case IPPROTO_ESP:
if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
level = esp_net_deflev;
else
level = esp_trans_deflev;
break;
case IPPROTO_AH:
if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
level = ah_net_deflev;
else
level = ah_trans_deflev;
break;
case IPPROTO_IPCOMP:
/*
* we don't really care, as IPcomp document says that
* we shouldn't compress small packets
*/
level = IPSEC_LEVEL_USE;
break;
default:
panic("%s: Illegal protocol defined %u", __func__,
isr->saidx.proto);
}
break;
case IPSEC_LEVEL_USE:
case IPSEC_LEVEL_REQUIRE:
level = isr->level;
break;
case IPSEC_LEVEL_UNIQUE:
level = IPSEC_LEVEL_REQUIRE;
break;
default:
panic("%s: Illegal IPsec level %u", __func__, isr->level);
}
return level;
}
/*
* Check security policy requirements against the actual
* packet contents. Return one if the packet should be
* reject as "invalid"; otherwiser return zero to have the
* packet treated as "valid".
*
* OUT:
* 0: valid
* 1: invalid
*/
int
ipsec_in_reject(const struct secpolicy *sp, const struct mbuf *m)
{
struct ipsecrequest *isr;
int need_auth;
KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: using SP\n", __func__);
kdebug_secpolicy(sp));
/* check policy */
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
return 1;
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
return 0;
}
IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
("%s: invalid policy %u", __func__, sp->policy));
/* XXX should compare policy against ipsec header history */
need_auth = 0;
for (isr = sp->req; isr != NULL; isr = isr->next) {
if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
continue;
switch (isr->saidx.proto) {
case IPPROTO_ESP:
if ((m->m_flags & M_DECRYPTED) == 0) {
KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
printf("%s: ESP m_flags:%x\n", __func__,
m->m_flags));
return 1;
}
if (!need_auth &&
isr->sav != NULL &&
isr->sav->tdb_authalgxform != NULL &&
(m->m_flags & M_AUTHIPDGM) == 0) {
KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
printf("%s: ESP/AH m_flags:%x\n", __func__,
m->m_flags));
return 1;
}
break;
case IPPROTO_AH:
need_auth = 1;
if ((m->m_flags & M_AUTHIPHDR) == 0) {
KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
printf("%s: AH m_flags:%x\n", __func__,
m->m_flags));
return 1;
}
break;
case IPPROTO_IPCOMP:
/*
* we don't really care, as IPcomp document
* says that we shouldn't compress small
* packets, IPComp policy should always be
* treated as being in "use" level.
*/
break;
}
}
return 0; /* valid */
}
/*
* Check AH/ESP integrity.
* This function is called from tcp_input(), udp_input(),
* and {ah,esp}4_input for tunnel mode
*/
int
ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
{
struct secpolicy *sp;
int error;
int result;
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
/* get SP for this packet.
* When we are called from ip_forward(), we call
* ipsec_getpolicybyaddr() with IP_FORWARDING flag.
*/
if (inp == NULL)
sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
else
sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND,
IN4PCB_TO_PCB(inp), &error);
if (sp != NULL) {
result = ipsec_in_reject(sp, m);
if (result)
IPSEC_STATINC(IPSEC_STAT_IN_POLVIO);
KEY_FREESP(&sp);
} else {
result = 0; /* XXX should be panic ?
* -> No, there may be error. */
}
return result;
}
#ifdef INET6
/*
* Check AH/ESP integrity.
* This function is called from tcp6_input(), udp6_input(),
* and {ah,esp}6_input for tunnel mode
*/
int
ipsec6_in_reject(struct mbuf *m, struct in6pcb *in6p)
{
struct secpolicy *sp = NULL;
int error;
int result;
/* sanity check */
if (m == NULL)
return 0; /* XXX should be panic ? */
/* get SP for this packet.
* When we are called from ip_forward(), we call
* ipsec_getpolicybyaddr() with IP_FORWARDING flag.
*/
if (in6p == NULL)
sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
else
sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND,
IN6PCB_TO_PCB(in6p),
&error);
if (sp != NULL) {
result = ipsec_in_reject(sp, m);
if (result)
IPSEC_STATINC(IPSEC_STAT_IN_POLVIO);
KEY_FREESP(&sp);
} else {
result = 0;
}
return result;
}
#endif
/*
* compute the byte size to be occupied by IPsec header.
* in case it is tunneled, it includes the size of outer IP header.
* NOTE: SP passed is free in this function.
*/
static size_t
ipsec_hdrsiz(const struct secpolicy *sp)
{
const struct ipsecrequest *isr;
size_t siz;
KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: using SP\n", __func__);
kdebug_secpolicy(sp));
switch (sp->policy) {
case IPSEC_POLICY_DISCARD:
case IPSEC_POLICY_BYPASS:
case IPSEC_POLICY_NONE:
return 0;
}
IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
("%s: invalid policy %u", __func__, sp->policy));
siz = 0;
for (isr = sp->req; isr != NULL; isr = isr->next) {
size_t clen = 0;
switch (isr->saidx.proto) {
case IPPROTO_ESP:
clen = esp_hdrsiz(isr->sav);
break;
case IPPROTO_AH:
clen = ah_hdrsiz(isr->sav);
break;
case IPPROTO_IPCOMP:
clen = sizeof(struct ipcomp);
break;
}
if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
switch (isr->saidx.dst.sa.sa_family) {
case AF_INET:
clen += sizeof(struct ip);
break;
#ifdef INET6
case AF_INET6:
clen += sizeof(struct ip6_hdr);
break;
#endif
default:
ipseclog((LOG_ERR, "%s: unknown AF %d in "
"IPsec tunnel SA\n", __func__,
((const struct sockaddr *)&isr->saidx.dst)
->sa_family));
break;
}
}
siz += clen;
}
return siz;
}
/* This function is called from ip_forward() and ipsec4_hdrsize_tcp(). */
size_t
ipsec4_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
{
struct secpolicy *sp;
int error;
size_t size;
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
IPSEC_ASSERT(inp == NULL || inp->inp_socket != NULL,
("%s: socket w/o inpcb", __func__));
/* get SP for this packet.
* When we are called from ip_forward(), we call
* ipsec_getpolicybyaddr() with IP_FORWARDING flag.
*/
if (inp == NULL)
sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
else
sp = ipsec_getpolicybysock(m, dir,
IN4PCB_TO_PCB(inp), &error);
if (sp != NULL) {
size = ipsec_hdrsiz(sp);
KEYDEBUG(KEYDEBUG_IPSEC_DATA, printf("%s: size:%lu.\n",
__func__, (unsigned long)size));
KEY_FREESP(&sp);
} else {
size = 0; /* XXX should be panic ? */
}
return size;
}
#ifdef INET6
/* This function is called from ipsec6_hdrsize_tcp(),
* and maybe from ip6_forward.()
*/
size_t
ipsec6_hdrsiz(struct mbuf *m, u_int dir, struct in6pcb *in6p)
{
struct secpolicy *sp;
int error;
size_t size;
IPSEC_ASSERT(m != NULL, ("%s: null mbuf", __func__));
IPSEC_ASSERT(in6p == NULL || in6p->in6p_socket != NULL,
("%s: socket w/o inpcb", __func__));
/* get SP for this packet */
/* XXX Is it right to call with IP_FORWARDING. */
if (in6p == NULL)
sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
else
sp = ipsec_getpolicybysock(m, dir,
IN6PCB_TO_PCB(in6p),
&error);
if (sp == NULL)
return 0;
size = ipsec_hdrsiz(sp);
KEYDEBUG(KEYDEBUG_IPSEC_DATA,
printf("%s: size:%zu.\n", __func__, size));
KEY_FREESP(&sp);
return size;
}
#endif /*INET6*/
/*
* Check the variable replay window.
* ipsec_chkreplay() performs replay check before ICV verification.
* ipsec_updatereplay() updates replay bitmap. This must be called after
* ICV verification (it also performs replay check, which is usually done
* beforehand).
* 0 (zero) is returned if packet disallowed, 1 if packet permitted.
*
* based on RFC 2401.
*/
int
ipsec_chkreplay(u_int32_t seq, const struct secasvar *sav)
{
const struct secreplay *replay;
u_int32_t diff;
int fr;
u_int32_t wsizeb; /* constant: bits of window size */
int frlast; /* constant: last frame */
IPSEC_SPLASSERT_SOFTNET(__func__);
IPSEC_ASSERT(sav != NULL, ("%s: Null SA", __func__));
IPSEC_ASSERT(sav->replay != NULL, ("%s: Null replay state", __func__));
replay = sav->replay;
if (replay->wsize == 0)
return 1; /* no need to check replay. */
/* constant */
frlast = replay->wsize - 1;
wsizeb = replay->wsize << 3;
/* sequence number of 0 is invalid */
if (seq == 0)
return 0;
/* first time is always okay */
if (replay->count == 0)
return 1;
if (seq > replay->lastseq) {
/* larger sequences are okay */
return 1;
} else {
/* seq is equal or less than lastseq. */
diff = replay->lastseq - seq;
/* over range to check, i.e. too old or wrapped */
if (diff >= wsizeb)
return 0;
fr = frlast - diff / 8;
/* this packet already seen ? */
if ((replay->bitmap)[fr] & (1 << (diff % 8)))
return 0;
/* out of order but good */
return 1;
}
}
/*
* check replay counter whether to update or not.
* OUT: 0: OK
* 1: NG
*/
int
ipsec_updatereplay(u_int32_t seq, const struct secasvar *sav)
{
struct secreplay *replay;
u_int32_t diff;
int fr;
u_int32_t wsizeb; /* constant: bits of window size */
int frlast; /* constant: last frame */
IPSEC_SPLASSERT_SOFTNET(__func__);
IPSEC_ASSERT(sav != NULL, ("%s: Null SA", __func__));
IPSEC_ASSERT(sav->replay != NULL, ("%s: Null replay state", __func__));
replay = sav->replay;
if (replay->wsize == 0)
goto ok; /* no need to check replay. */
/* constant */
frlast = replay->wsize - 1;
wsizeb = replay->wsize << 3;
/* sequence number of 0 is invalid */
if (seq == 0)
return 1;
/* first time */
if (replay->count == 0) {
replay->lastseq = seq;
memset(replay->bitmap, 0, replay->wsize);
(replay->bitmap)[frlast] = 1;
goto ok;
}
if (seq > replay->lastseq) {
/* seq is larger than lastseq. */
diff = seq - replay->lastseq;
/* new larger sequence number */
if (diff < wsizeb) {
/* In window */
/* set bit for this packet */
vshiftl(replay->bitmap, diff, replay->wsize);
(replay->bitmap)[frlast] |= 1;
} else {
/* this packet has a "way larger" */
memset(replay->bitmap, 0, replay->wsize);
(replay->bitmap)[frlast] = 1;
}
replay->lastseq = seq;
/* larger is good */
} else {
/* seq is equal or less than lastseq. */
diff = replay->lastseq - seq;
/* over range to check, i.e. too old or wrapped */
if (diff >= wsizeb)
return 1;
fr = frlast - diff / 8;
/* this packet already seen ? */
if ((replay->bitmap)[fr] & (1 << (diff % 8)))
return 1;
/* mark as seen */
(replay->bitmap)[fr] |= (1 << (diff % 8));
/* out of order but good */
}
ok:
if (replay->count == ~0) {
/* set overflow flag */
replay->overflow++;
/* don't increment, no more packets accepted */
if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
return 1;
ipseclog((LOG_WARNING, "replay counter made %d cycle. %s\n",
replay->overflow, ipsec_logsastr(sav)));
}
replay->count++;
return 0;
}
/*
* shift variable length bunffer to left.
* IN: bitmap: pointer to the buffer
* nbit: the number of to shift.
* wsize: buffer size (bytes).
*/
static void
vshiftl(unsigned char *bitmap, int nbit, int wsize)
{
int s, j, i;
unsigned char over;
for (j = 0; j < nbit; j += 8) {
s = (nbit - j < 8) ? (nbit - j): 8;
bitmap[0] <<= s;
for (i = 1; i < wsize; i++) {
over = (bitmap[i] >> (8 - s));
bitmap[i] <<= s;
bitmap[i-1] |= over;
}
}
return;
}
/* Return a printable string for the IPv4 address. */
static char *
inet_ntoa4(struct in_addr ina)
{
static char buf[4][4 * sizeof "123" + 4];
unsigned char *ucp = (unsigned char *) &ina;
static int i = 3;
i = (i + 1) % 4;
snprintf(buf[i], sizeof(buf[i]), "%d.%d.%d.%d",
ucp[0] & 0xff, ucp[1] & 0xff, ucp[2] & 0xff, ucp[3] & 0xff);
return (buf[i]);
}
/* Return a printable string for the address. */
const char *
ipsec_address(const union sockaddr_union *sa)
{
switch (sa->sa.sa_family) {
#if INET
case AF_INET:
return inet_ntoa4(sa->sin.sin_addr);
#endif /* INET */
#if INET6
case AF_INET6:
return ip6_sprintf(&sa->sin6.sin6_addr);
#endif /* INET6 */
default:
return "(unknown address family)";
}
}
const char *
ipsec_logsastr(const struct secasvar *sav)
{
static char buf[256];
char *p;
const struct secasindex *saidx = &sav->sah->saidx;
IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
("%s: address family mismatch", __func__));
p = buf;
snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
while (p && *p)
p++;
/* NB: only use ipsec_address on one address at a time */
snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
ipsec_address(&saidx->src));
while (p && *p)
p++;
snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
ipsec_address(&saidx->dst));
return buf;
}
void
ipsec_dumpmbuf(struct mbuf *m)
{
int totlen;
int i;
u_char *p;
totlen = 0;
printf("---\n");
while (m) {
p = mtod(m, u_char *);
for (i = 0; i < m->m_len; i++) {
printf("%02x ", p[i]);
totlen++;
if (totlen % 16 == 0)
printf("\n");
}
m = m->m_next;
}
if (totlen % 16 != 0)
printf("\n");
printf("---\n");
}
#ifdef INET6
struct secpolicy *
ipsec6_check_policy(struct mbuf *m, const struct socket *so,
int flags, int *needipsecp, int *errorp)
{
struct in6pcb *in6p = NULL;
struct secpolicy *sp = NULL;
int s;
int error = 0;
int needipsec = 0;
if (so != NULL && so->so_proto->pr_domain->dom_family == AF_INET6)
in6p = sotoin6pcb(so);
if (!ipsec_outdone(m)) {
s = splsoftnet();
if (in6p != NULL &&
IPSEC_PCB_SKIP_IPSEC(in6p->in6p_sp, IPSEC_DIR_OUTBOUND)) {
splx(s);
goto skippolicycheck;
}
sp = ipsec6_checkpolicy(m, IPSEC_DIR_OUTBOUND, flags, &error,in6p);
/*
* There are four return cases:
* sp != NULL apply IPsec policy
* sp == NULL, error == 0 no IPsec handling needed
* sp == NULL, error == -EINVAL discard packet w/o error
* sp == NULL, error != 0 discard packet, report error
*/
splx(s);
if (sp == NULL) {
/*
* Caller must check the error return to see if it needs to discard
* the packet.
*/
needipsec = 0;
} else {
needipsec = 1;
}
}
skippolicycheck:;
*errorp = error;
*needipsecp = needipsec;
return sp;
}
int
ipsec6_input(struct mbuf *m)
{
struct m_tag *mtag;
struct tdb_ident *tdbi;
struct secpolicy *sp;
int s, error;
/*
* Check if the packet has already had IPsec
* processing done. If so, then just pass it
* along. This tag gets set during AH, ESP,
* etc. input handling, before the packet is
* returned to the ip input queue for delivery.
*/
mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE,
NULL);
s = splsoftnet();
if (mtag != NULL) {
tdbi = (struct tdb_ident *)(mtag + 1);
sp = ipsec_getpolicy(tdbi,
IPSEC_DIR_INBOUND);
} else {
sp = ipsec_getpolicybyaddr(m,
IPSEC_DIR_INBOUND, IP_FORWARDING,
&error);
}
if (sp != NULL) {
/*
* Check security policy against packet
* attributes.
*/
error = ipsec_in_reject(sp, m);
KEY_FREESP(&sp);
} else {
/* XXX error stat??? */
error = EINVAL;
DPRINTF(("ip6_input: no SP, packet"
" discarded\n"));/*XXX*/
}
splx(s);
return error;
}
#endif /* INET6 */
/* XXX this stuff doesn't belong here... */
static struct xformsw *xforms = NULL;
/*
* Register a transform; typically at system startup.
*/
void
xform_register(struct xformsw *xsp)
{
xsp->xf_next = xforms;
xforms = xsp;
}
/*
* Initialize transform support in an sav.
*/
int
xform_init(struct secasvar *sav, int xftype)
{
struct xformsw *xsp;
if (sav->tdb_xform != NULL) /* previously initialized */
return 0;
for (xsp = xforms; xsp; xsp = xsp->xf_next)
if (xsp->xf_type == xftype)
return (*xsp->xf_init)(sav, xsp);
DPRINTF(("%s: no match for xform type %d\n", __func__, xftype));
return EINVAL;
}
void
nat_t_ports_get(struct mbuf *m, u_int16_t *dport, u_int16_t *sport) {
struct m_tag *tag;
if ((tag = m_tag_find(m, PACKET_TAG_IPSEC_NAT_T_PORTS, NULL))) {
*sport = ((u_int16_t *)(tag + 1))[0];
*dport = ((u_int16_t *)(tag + 1))[1];
} else
*sport = *dport = 0;
}
#ifdef __NetBSD__
/*
* XXXJRT This should be done as a protosw init call.
*/
void
ipsec_attach(void)
{
ipsecstat_percpu = percpu_alloc(sizeof(uint64_t) * IPSEC_NSTATS);
ah_attach();
esp_attach();
ipcomp_attach();
ipe4_attach();
#ifdef TCP_SIGNATURE
tcpsignature_attach();
#endif
}
#endif /* __NetBSD__ */
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