NetBSD/sys/netipsec/xform_ipcomp.c
drochner 22beeb59d8 Make sure the mbufs in the input path (only the parts which we are going
to modify in the AH case) are writable/non-shared.
This addresses PR kern/33162 by Jeff Rizzo, and replaces the insufficient
patch from that time by a radical solution.
(The PR's problem had been worked around by rev.1.3 of xennetback_xenbus.c,
so it needs a network driver modification to reproduce it.)
Being here, clarify a bit of ipcomp -- uncompression is done in-place,
the header must be removed explicitly.
2012-01-25 20:31:23 +00:00

686 lines
18 KiB
C

/* $NetBSD: xform_ipcomp.c,v 1.29 2012/01/25 20:31:23 drochner Exp $ */
/* $FreeBSD: src/sys/netipsec/xform_ipcomp.c,v 1.1.4.1 2003/01/24 05:11:36 sam Exp $ */
/* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
/*
* Copyright (c) 2001 Jean-Jacques Bernard-Gundol (jj@wabbitt.org)
*
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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: xform_ipcomp.c,v 1.29 2012/01/25 20:31:23 drochner Exp $");
/* IP payload compression protocol (IPComp), see RFC 2393 */
#include "opt_inet.h"
#ifdef __FreeBSD__
#include "opt_inet6.h"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>
#include <sys/socketvar.h> /* for softnet_lock */
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <net/route.h>
#include <netipsec/ipsec.h>
#include <netipsec/ipsec_private.h>
#include <netipsec/xform.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netipsec/ipsec6.h>
#endif
#include <netipsec/ipcomp.h>
#include <netipsec/ipcomp_var.h>
#include <netipsec/key.h>
#include <netipsec/key_debug.h>
#include <netipsec/ipsec_osdep.h>
#include <opencrypto/cryptodev.h>
#include <opencrypto/deflate.h>
#include <opencrypto/xform.h>
percpu_t *ipcompstat_percpu;
int ipcomp_enable = 1;
#ifdef __FreeBSD__
SYSCTL_DECL(_net_inet_ipcomp);
SYSCTL_INT(_net_inet_ipcomp, OID_AUTO,
ipcomp_enable, CTLFLAG_RW, &ipcomp_enable, 0, "");
SYSCTL_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
stats, CTLFLAG_RD, &ipcompstat, ipcompstat, "");
#endif /* __FreeBSD__ */
static int ipcomp_input_cb(struct cryptop *crp);
static int ipcomp_output_cb(struct cryptop *crp);
const struct comp_algo *
ipcomp_algorithm_lookup(int alg)
{
if (alg >= IPCOMP_ALG_MAX)
return NULL;
switch (alg) {
case SADB_X_CALG_DEFLATE:
return &comp_algo_deflate_nogrow;
}
return NULL;
}
/*
* ipcomp_init() is called when an CPI is being set up.
*/
static int
ipcomp_init(struct secasvar *sav, const struct xformsw *xsp)
{
const struct comp_algo *tcomp;
struct cryptoini cric;
int ses;
/* NB: algorithm really comes in alg_enc and not alg_comp! */
tcomp = ipcomp_algorithm_lookup(sav->alg_enc);
if (tcomp == NULL) {
DPRINTF(("ipcomp_init: unsupported compression algorithm %d\n",
sav->alg_comp));
return EINVAL;
}
sav->alg_comp = sav->alg_enc; /* set for doing histogram */
sav->tdb_xform = xsp;
sav->tdb_compalgxform = tcomp;
/* Initialize crypto session */
memset(&cric, 0, sizeof (cric));
cric.cri_alg = sav->tdb_compalgxform->type;
ses = crypto_newsession(&sav->tdb_cryptoid, &cric, crypto_support);
return ses;
}
/*
* ipcomp_zeroize() used when IPCA is deleted
*/
static int
ipcomp_zeroize(struct secasvar *sav)
{
int err;
err = crypto_freesession(sav->tdb_cryptoid);
sav->tdb_cryptoid = 0;
return err;
}
/*
* ipcomp_input() gets called to uncompress an input packet
*/
static int
ipcomp_input(struct mbuf *m, const struct secasvar *sav, int skip, int protoff)
{
struct tdb_crypto *tc;
struct cryptodesc *crdc;
struct cryptop *crp;
int error, hlen = IPCOMP_HLENGTH;
IPSEC_SPLASSERT_SOFTNET("ipcomp_input");
/* Get crypto descriptors */
crp = crypto_getreq(1);
if (crp == NULL) {
m_freem(m);
DPRINTF(("ipcomp_input: no crypto descriptors\n"));
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
return ENOBUFS;
}
/* Get IPsec-specific opaque pointer */
tc = (struct tdb_crypto *) malloc(sizeof (*tc), M_XDATA, M_NOWAIT|M_ZERO);
if (tc == NULL) {
m_freem(m);
crypto_freereq(crp);
DPRINTF(("ipcomp_input: cannot allocate tdb_crypto\n"));
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
return ENOBUFS;
}
error = m_makewritable(&m, 0, m->m_pkthdr.len, M_NOWAIT);
if (error) {
DPRINTF(("ipcomp_input: m_makewritable failed\n"));
m_freem(m);
free(tc, M_XDATA);
crypto_freereq(crp);
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
return error;
}
crdc = crp->crp_desc;
crdc->crd_skip = skip + hlen;
crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
crdc->crd_inject = 0; /* unused */
tc->tc_ptr = 0;
/* Decompression operation */
crdc->crd_alg = sav->tdb_compalgxform->type;
/* Crypto operation descriptor */
crp->crp_ilen = m->m_pkthdr.len - (skip + hlen);
crp->crp_olen = MCLBYTES; /* hint to decompression code */
crp->crp_flags = CRYPTO_F_IMBUF;
crp->crp_buf = m;
crp->crp_callback = ipcomp_input_cb;
crp->crp_sid = sav->tdb_cryptoid;
crp->crp_opaque = tc;
/* These are passed as-is to the callback */
tc->tc_spi = sav->spi;
tc->tc_dst = sav->sah->saidx.dst;
tc->tc_proto = sav->sah->saidx.proto;
tc->tc_protoff = protoff;
tc->tc_skip = skip;
return crypto_dispatch(crp);
}
#ifdef INET6
#define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) do { \
if (saidx->dst.sa.sa_family == AF_INET6) { \
error = ipsec6_common_input_cb(m, sav, skip, protoff, mtag); \
} else { \
error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag); \
} \
} while (0)
#else
#define IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, mtag) \
(error = ipsec4_common_input_cb(m, sav, skip, protoff, mtag))
#endif
/*
* IPComp input callback from the crypto driver.
*/
static int
ipcomp_input_cb(struct cryptop *crp)
{
struct cryptodesc *crd;
struct tdb_crypto *tc;
int skip, protoff;
struct mtag *mtag;
struct mbuf *m;
struct secasvar *sav;
struct secasindex *saidx;
int s, hlen = IPCOMP_HLENGTH, error, clen;
u_int8_t nproto;
void *addr;
u_int16_t dport = 0;
u_int16_t sport = 0;
#ifdef IPSEC_NAT_T
struct m_tag * tag = NULL;
#endif
crd = crp->crp_desc;
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("ipcomp_input_cb: null opaque crypto data area!"));
skip = tc->tc_skip;
protoff = tc->tc_protoff;
mtag = (struct mtag *) tc->tc_ptr;
m = (struct mbuf *) crp->crp_buf;
#ifdef IPSEC_NAT_T
/* find the source port for NAT-T */
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];
}
#endif
s = splsoftnet();
mutex_enter(softnet_lock);
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, sport, dport);
if (sav == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_NOTDB);
DPRINTF(("ipcomp_input_cb: SA expired while in crypto\n"));
error = ENOBUFS; /*XXX*/
goto bad;
}
saidx = &sav->sah->saidx;
IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
saidx->dst.sa.sa_family == AF_INET6,
("ipcomp_input_cb: unexpected protocol family %u",
saidx->dst.sa.sa_family));
/* Check for crypto errors */
if (crp->crp_etype) {
/* Reset the session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN) {
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
return crypto_dispatch(crp);
}
IPCOMP_STATINC(IPCOMP_STAT_NOXFORM);
DPRINTF(("ipcomp_input_cb: crypto error %d\n", crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
DPRINTF(("ipcomp_input_cb: null mbuf returned from crypto\n"));
error = EINVAL;
goto bad;
}
IPCOMP_STATINC(IPCOMP_STAT_HIST + sav->alg_comp);
/* Update the counters */
IPCOMP_STATADD(IPCOMP_STAT_IBYTES, m->m_pkthdr.len - skip - hlen);
clen = crp->crp_olen; /* Length of data after processing */
/* Release the crypto descriptors */
free(tc, M_XDATA), tc = NULL;
crypto_freereq(crp), crp = NULL;
/* In case it's not done already, adjust the size of the mbuf chain */
m->m_pkthdr.len = clen + hlen + skip;
if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == 0) {
IPCOMP_STATINC(IPCOMP_STAT_HDROPS); /*XXX*/
DPRINTF(("ipcomp_input_cb: m_pullup failed\n"));
error = EINVAL; /*XXX*/
goto bad;
}
/* Keep the next protocol field */
addr = (uint8_t*) mtod(m, struct ip *) + skip;
nproto = ((struct ipcomp *) addr)->comp_nxt;
if (nproto == IPPROTO_IPCOMP || nproto == IPPROTO_AH || nproto == IPPROTO_ESP) {
IPCOMP_STATINC(IPCOMP_STAT_HDROPS);
DPRINTF(("ipcomp_input_cb: nested ipcomp, IPCA %s/%08lx\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
error = EINVAL;
goto bad;
}
/* Remove the IPCOMP header */
error = m_striphdr(m, skip, hlen);
if (error) {
IPCOMP_STATINC(IPCOMP_STAT_HDROPS);
DPRINTF(("ipcomp_input_cb: bad mbuf chain, IPCA %s/%08lx\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
goto bad;
}
/* Restore the Next Protocol field */
m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
IPSEC_COMMON_INPUT_CB(m, sav, skip, protoff, NULL);
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
return error;
bad:
if (sav)
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
if (m)
m_freem(m);
if (tc != NULL)
free(tc, M_XDATA);
if (crp)
crypto_freereq(crp);
return error;
}
/*
* IPComp output routine, called by ipsec[46]_process_packet()
*/
static int
ipcomp_output(
struct mbuf *m,
struct ipsecrequest *isr,
struct mbuf **mp,
int skip,
int protoff
)
{
const struct secasvar *sav;
const struct comp_algo *ipcompx;
int error, ralen, hlen, maxpacketsize;
struct cryptodesc *crdc;
struct cryptop *crp;
struct tdb_crypto *tc;
IPSEC_SPLASSERT_SOFTNET("ipcomp_output");
sav = isr->sav;
IPSEC_ASSERT(sav != NULL, ("ipcomp_output: null SA"));
ipcompx = sav->tdb_compalgxform;
IPSEC_ASSERT(ipcompx != NULL, ("ipcomp_output: null compression xform"));
ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
/* Don't process the packet if it is too short */
if (ralen < ipcompx->minlen) {
IPCOMP_STATINC(IPCOMP_STAT_MINLEN);
return ipsec_process_done(m,isr);
}
hlen = IPCOMP_HLENGTH;
IPCOMP_STATINC(IPCOMP_STAT_OUTPUT);
/* Check for maximum packet size violations. */
switch (sav->sah->saidx.dst.sa.sa_family) {
#ifdef INET
case AF_INET:
maxpacketsize = IP_MAXPACKET;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
maxpacketsize = IPV6_MAXPACKET;
break;
#endif /* INET6 */
default:
IPCOMP_STATINC(IPCOMP_STAT_NOPF);
DPRINTF(("ipcomp_output: unknown/unsupported protocol family %d"
", IPCA %s/%08lx\n",
sav->sah->saidx.dst.sa.sa_family,
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
error = EPFNOSUPPORT;
goto bad;
}
if (skip + hlen + ralen > maxpacketsize) {
IPCOMP_STATINC(IPCOMP_STAT_TOOBIG);
DPRINTF(("ipcomp_output: packet in IPCA %s/%08lx got too big "
"(len %u, max len %u)\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi),
skip + hlen + ralen, maxpacketsize));
error = EMSGSIZE;
goto bad;
}
/* Update the counters */
IPCOMP_STATADD(IPCOMP_STAT_OBYTES, m->m_pkthdr.len - skip);
m = m_clone(m);
if (m == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_HDROPS);
DPRINTF(("ipcomp_output: cannot clone mbuf chain, IPCA %s/%08lx\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
error = ENOBUFS;
goto bad;
}
/* Ok now, we can pass to the crypto processing */
/* Get crypto descriptors */
crp = crypto_getreq(1);
if (crp == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
DPRINTF(("ipcomp_output: failed to acquire crypto descriptor\n"));
error = ENOBUFS;
goto bad;
}
crdc = crp->crp_desc;
/* Compression descriptor */
crdc->crd_skip = skip;
crdc->crd_len = m->m_pkthdr.len - skip;
crdc->crd_flags = CRD_F_COMP;
crdc->crd_inject = skip;
/* Compression operation */
crdc->crd_alg = ipcompx->type;
/* IPsec-specific opaque crypto info */
tc = (struct tdb_crypto *) malloc(sizeof(struct tdb_crypto),
M_XDATA, M_NOWAIT|M_ZERO);
if (tc == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
DPRINTF(("ipcomp_output: failed to allocate tdb_crypto\n"));
crypto_freereq(crp);
error = ENOBUFS;
goto bad;
}
tc->tc_isr = isr;
tc->tc_spi = sav->spi;
tc->tc_dst = sav->sah->saidx.dst;
tc->tc_proto = sav->sah->saidx.proto;
tc->tc_skip = skip;
tc->tc_protoff = protoff;
/* Crypto operation descriptor */
crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
crp->crp_flags = CRYPTO_F_IMBUF;
crp->crp_buf = m;
crp->crp_callback = ipcomp_output_cb;
crp->crp_opaque = tc;
crp->crp_sid = sav->tdb_cryptoid;
return crypto_dispatch(crp);
bad:
if (m)
m_freem(m);
return (error);
}
/*
* IPComp output callback from the crypto driver.
*/
static int
ipcomp_output_cb(struct cryptop *crp)
{
struct tdb_crypto *tc;
struct ipsecrequest *isr;
struct secasvar *sav;
struct mbuf *m, *mo;
int s, error, skip, rlen, roff;
u_int8_t prot;
u_int16_t cpi;
struct ipcomp * ipcomp;
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("ipcomp_output_cb: null opaque data area!"));
m = (struct mbuf *) crp->crp_buf;
skip = tc->tc_skip;
rlen = crp->crp_ilen - skip;
s = splsoftnet();
mutex_enter(softnet_lock);
isr = tc->tc_isr;
sav = KEY_ALLOCSA(&tc->tc_dst, tc->tc_proto, tc->tc_spi, 0, 0);
if (sav == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_NOTDB);
DPRINTF(("ipcomp_output_cb: SA expired while in crypto\n"));
error = ENOBUFS; /*XXX*/
goto bad;
}
IPSEC_ASSERT(isr->sav == sav, ("ipcomp_output_cb: SA changed\n"));
/* Check for crypto errors */
if (crp->crp_etype) {
/* Reset session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN) {
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
return crypto_dispatch(crp);
}
IPCOMP_STATINC(IPCOMP_STAT_NOXFORM);
DPRINTF(("ipcomp_output_cb: crypto error %d\n", crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_CRYPTO);
DPRINTF(("ipcomp_output_cb: bogus return buffer from crypto\n"));
error = EINVAL;
goto bad;
}
IPCOMP_STATINC(IPCOMP_STAT_HIST + sav->alg_comp);
if (rlen > crp->crp_olen) {
/* Inject IPCOMP header */
mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
if (mo == NULL) {
IPCOMP_STATINC(IPCOMP_STAT_WRAP);
DPRINTF(("ipcomp_output: failed to inject IPCOMP header for "
"IPCA %s/%08lx\n",
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
error = ENOBUFS;
goto bad;
}
ipcomp = (struct ipcomp *)(mtod(mo, char *) + roff);
/* Initialize the IPCOMP header */
/* XXX alignment always correct? */
switch (sav->sah->saidx.dst.sa.sa_family) {
#ifdef INET
case AF_INET:
ipcomp->comp_nxt = mtod(m, struct ip *)->ip_p;
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
ipcomp->comp_nxt = mtod(m, struct ip6_hdr *)->ip6_nxt;
break;
#endif
}
ipcomp->comp_flags = 0;
if ((sav->flags & SADB_X_EXT_RAWCPI) == 0)
cpi = sav->alg_enc;
else
cpi = ntohl(sav->spi) & 0xffff;
ipcomp->comp_cpi = htons(cpi);
/* Fix Next Protocol in IPv4/IPv6 header */
prot = IPPROTO_IPCOMP;
m_copyback(m, tc->tc_protoff, sizeof(u_int8_t), (u_char *)&prot);
/* Adjust the length in the IP header */
switch (sav->sah->saidx.dst.sa.sa_family) {
#ifdef INET
case AF_INET:
mtod(m, struct ip *)->ip_len = htons(m->m_pkthdr.len);
break;
#endif /* INET */
#ifdef INET6
case AF_INET6:
mtod(m, struct ip6_hdr *)->ip6_plen =
htons(m->m_pkthdr.len) - sizeof(struct ip6_hdr);
break;
#endif /* INET6 */
default:
IPCOMP_STATINC(IPCOMP_STAT_NOPF);
DPRINTF(("ipcomp_output: unknown/unsupported protocol "
"family %d, IPCA %s/%08lx\n",
sav->sah->saidx.dst.sa.sa_family,
ipsec_address(&sav->sah->saidx.dst),
(u_long) ntohl(sav->spi)));
error = EPFNOSUPPORT;
goto bad;
}
} else {
/* compression was useless, we have lost time */
IPCOMP_STATINC(IPCOMP_STAT_USELESS);
DPRINTF(("ipcomp_output_cb: compression was useless : initial size was %d"
"and compressed size is %d\n", rlen, crp->crp_olen));
}
/* Release the crypto descriptor */
free(tc, M_XDATA);
crypto_freereq(crp);
/* NB: m is reclaimed by ipsec_process_done. */
error = ipsec_process_done(m, isr);
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
return error;
bad:
if (sav)
KEY_FREESAV(&sav);
mutex_exit(softnet_lock);
splx(s);
if (m)
m_freem(m);
free(tc, M_XDATA);
crypto_freereq(crp);
return error;
}
static struct xformsw ipcomp_xformsw = {
XF_IPCOMP, XFT_COMP, "IPcomp",
ipcomp_init, ipcomp_zeroize, ipcomp_input,
ipcomp_output,
NULL,
};
INITFN void
ipcomp_attach(void)
{
ipcompstat_percpu = percpu_alloc(sizeof(uint64_t) * IPCOMP_NSTATS);
xform_register(&ipcomp_xformsw);
}
#ifdef __FreeBSD__
SYSINIT(ipcomp_xform_init, SI_SUB_DRIVERS, SI_ORDER_FIRST, ipcomp_attach, NULL)
#endif /* __FreeBSD__ */