/* $FreeBSD$ */
/* $OpenBSD: ip_ipcomp.c,v 1.1 2001/07/05 12:08:52 jjbg Exp $ */
/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
*/
/* IP payload compression protocol (IPComp), see RFC 2393 */
#include "opt_inet.h"
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/kernel.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/ip_encap.h>
#include <net/netisr.h>
#include <net/vnet.h>
#include <net/if.h> /* XXXGL: net_epoch should move out there */
#include <net/if_var.h> /* XXXGL: net_epoch should move out there */
#include <netipsec/ipsec.h>
#include <netipsec/xform.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.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 <opencrypto/cryptodev.h>
#include <opencrypto/deflate.h>
#include <opencrypto/xform.h>
VNET_DEFINE(int, ipcomp_enable) = 1;
VNET_PCPUSTAT_DEFINE(struct ipcompstat, ipcompstat);
VNET_PCPUSTAT_SYSINIT(ipcompstat);
#ifdef VIMAGE
VNET_PCPUSTAT_SYSUNINIT(ipcompstat);
#endif /* VIMAGE */
SYSCTL_DECL(_net_inet_ipcomp);
SYSCTL_INT(_net_inet_ipcomp, OID_AUTO, ipcomp_enable,
CTLFLAG_VNET | CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, "");
SYSCTL_VNET_PCPUSTAT(_net_inet_ipcomp, IPSECCTL_STATS, stats,
struct ipcompstat, ipcompstat,
"IPCOMP statistics (struct ipcompstat, netipsec/ipcomp_var.h");
static MALLOC_DEFINE(M_IPCOMP, "ipcomp", "IPCOMP");
static int ipcomp_input_cb(struct cryptop *crp);
static int ipcomp_output_cb(struct cryptop *crp);
/*
* RFC 3173 p 2.2. Non-Expansion Policy:
* If the total size of a compressed payload and the IPComp header, as
* defined in section 3, is not smaller than the size of the original
* payload, the IP datagram MUST be sent in the original non-compressed
* form.
*
* When we use IPComp in tunnel mode, for small packets we will receive
* encapsulated IP-IP datagrams without any compression and without IPComp
* header.
*/
static int
ipcomp_encapcheck(union sockaddr_union *src, union sockaddr_union *dst)
{
struct secasvar *sav;
sav = key_allocsa_tunnel(src, dst, IPPROTO_IPCOMP);
if (sav == NULL)
return (0);
key_freesav(&sav);
if (src->sa.sa_family == AF_INET)
return (sizeof(struct in_addr) << 4);
else
return (sizeof(struct in6_addr) << 4);
}
static int
ipcomp_nonexp_input(struct mbuf *m, int off, int proto, void *arg __unused)
{
int isr;
NET_EPOCH_ASSERT();
switch (proto) {
#ifdef INET
case IPPROTO_IPV4:
isr = NETISR_IP;
break;
#endif
#ifdef INET6
case IPPROTO_IPV6:
isr = NETISR_IPV6;
break;
#endif
default:
IPCOMPSTAT_INC(ipcomps_nopf);
m_freem(m);
return (IPPROTO_DONE);
}
m_adj(m, off);
IPCOMPSTAT_ADD(ipcomps_ibytes, m->m_pkthdr.len);
IPCOMPSTAT_INC(ipcomps_input);
netisr_dispatch(isr, m);
return (IPPROTO_DONE);
}
/*
* ipcomp_init() is called when an CPI is being set up.
*/
static int
ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
{
const struct comp_algo *tcomp;
struct crypto_session_params csp;
/* NB: algorithm really comes in alg_enc and not alg_comp! */
tcomp = comp_algorithm_lookup(sav->alg_enc);
if (tcomp == NULL) {
DPRINTF(("%s: unsupported compression algorithm %d\n", __func__,
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(&csp, 0, sizeof(csp));
csp.csp_mode = CSP_MODE_COMPRESS;
csp.csp_cipher_alg = sav->tdb_compalgxform->type;
return crypto_newsession(&sav->tdb_cryptoid, &csp, V_crypto_support);
}
/*
* ipcomp_cleanup() used when IPCA is deleted
*/
static void
ipcomp_cleanup(struct secasvar *sav)
{
crypto_freesession(sav->tdb_cryptoid);
sav->tdb_cryptoid = NULL;
}
/*
* ipcomp_input() gets called to uncompress an input packet
*/
static int
ipcomp_input(struct mbuf *m, struct secasvar *sav, int skip, int protoff)
{
struct xform_data *xd;
struct cryptop *crp;
struct ipcomp *ipcomp;
crypto_session_t cryptoid;
caddr_t addr;
int error, hlen = IPCOMP_HLENGTH;
/*
* Check that the next header of the IPComp is not IPComp again, before
* doing any real work. Given it is not possible to do double
* compression it means someone is playing tricks on us.
*/
error = ENOBUFS;
if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
DPRINTF(("%s: m_pullup failed\n", __func__));
key_freesav(&sav);
return (error);
}
addr = (caddr_t) mtod(m, struct ip *) + skip;
ipcomp = (struct ipcomp *)addr;
if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
IPCOMPSTAT_INC(ipcomps_pdrops); /* XXX have our own stats? */
DPRINTF(("%s: recursive compression detected\n", __func__));
error = EINVAL;
goto bad;
}
SECASVAR_LOCK(sav);
cryptoid = sav->tdb_cryptoid;
SECASVAR_UNLOCK(sav);
/* Get crypto descriptors */
crp = crypto_getreq(cryptoid, M_NOWAIT);
if (crp == NULL) {
DPRINTF(("%s: no crypto descriptors\n", __func__));
IPCOMPSTAT_INC(ipcomps_crypto);
goto bad;
}
/* Get IPsec-specific opaque pointer */
xd = malloc(sizeof(*xd), M_IPCOMP, M_NOWAIT | M_ZERO);
if (xd == NULL) {
DPRINTF(("%s: cannot allocate xform_data\n", __func__));
IPCOMPSTAT_INC(ipcomps_crypto);
crypto_freereq(crp);
goto bad;
}
/* Decompression operation */
crp->crp_op = CRYPTO_OP_DECOMPRESS;
crp->crp_payload_start = skip + hlen;
crp->crp_payload_length = m->m_pkthdr.len - (skip + hlen);
/* Crypto operation descriptor */
crp->crp_flags = CRYPTO_F_CBIFSYNC;
crypto_use_mbuf(crp, m);
crp->crp_callback = ipcomp_input_cb;
crp->crp_opaque = xd;
/* These are passed as-is to the callback */
xd->sav = sav;
xd->protoff = protoff;
xd->skip = skip;
xd->vnet = curvnet;
xd->cryptoid = cryptoid;
SECASVAR_LOCK(sav);
crp->crp_session = xd->cryptoid = sav->tdb_cryptoid;
SECASVAR_UNLOCK(sav);
return crypto_dispatch(crp);
bad:
m_freem(m);
key_freesav(&sav);
return (error);
}
/*
* IPComp input callback from the crypto driver.
*/
static int
ipcomp_input_cb(struct cryptop *crp)
{
IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
struct xform_data *xd;
struct mbuf *m;
struct secasvar *sav;
struct secasindex *saidx;
caddr_t addr;
crypto_session_t cryptoid;
int hlen = IPCOMP_HLENGTH, error, clen;
int skip, protoff;
uint8_t nproto;
m = crp->crp_buf.cb_mbuf;
xd = crp->crp_opaque;
CURVNET_SET(xd->vnet);
sav = xd->sav;
skip = xd->skip;
protoff = xd->protoff;
cryptoid = xd->cryptoid;
saidx = &sav->sah->saidx;
IPSEC_ASSERT(saidx->dst.sa.sa_family == AF_INET ||
saidx->dst.sa.sa_family == AF_INET6,
("unexpected protocol family %u", saidx->dst.sa.sa_family));
/* Check for crypto errors */
if (crp->crp_etype) {
if (crp->crp_etype == EAGAIN) {
/* Reset the session ID */
if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
crypto_freesession(cryptoid);
xd->cryptoid = crp->crp_session;
CURVNET_RESTORE();
return (crypto_dispatch(crp));
}
IPCOMPSTAT_INC(ipcomps_noxform);
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
IPCOMPSTAT_INC(ipcomps_crypto);
DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
error = EINVAL;
goto bad;
}
IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
clen = crp->crp_olen; /* Length of data after processing */
/* Release the crypto descriptors */
free(xd, M_IPCOMP), xd = 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)) == NULL) {
IPCOMPSTAT_INC(ipcomps_hdrops); /*XXX*/
DPRINTF(("%s: m_pullup failed\n", __func__));
error = EINVAL; /*XXX*/
goto bad;
}
/* Keep the next protocol field */
addr = (caddr_t) mtod(m, struct ip *) + skip;
nproto = ((struct ipcomp *) addr)->comp_nxt;
/* Remove the IPCOMP header */
error = m_striphdr(m, skip, hlen);
if (error) {
IPCOMPSTAT_INC(ipcomps_hdrops);
DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
(u_long) ntohl(sav->spi)));
goto bad;
}
/* Restore the Next Protocol field */
m_copyback(m, protoff, sizeof (u_int8_t), (u_int8_t *) &nproto);
switch (saidx->dst.sa.sa_family) {
#ifdef INET6
case AF_INET6:
error = ipsec6_common_input_cb(m, sav, skip, protoff);
break;
#endif
#ifdef INET
case AF_INET:
error = ipsec4_common_input_cb(m, sav, skip, protoff);
break;
#endif
default:
panic("%s: Unexpected address family: %d saidx=%p", __func__,
saidx->dst.sa.sa_family, saidx);
}
CURVNET_RESTORE();
return error;
bad:
CURVNET_RESTORE();
if (sav != NULL)
key_freesav(&sav);
if (m != NULL)
m_freem(m);
if (xd != NULL)
free(xd, M_IPCOMP);
if (crp != NULL)
crypto_freereq(crp);
return error;
}
/*
* IPComp output routine, called by ipsec[46]_perform_request()
*/
static int
ipcomp_output(struct mbuf *m, struct secpolicy *sp, struct secasvar *sav,
u_int idx, int skip, int protoff)
{
IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
const struct comp_algo *ipcompx;
struct cryptop *crp;
struct xform_data *xd;
crypto_session_t cryptoid;
int error, ralen, maxpacketsize;
IPSEC_ASSERT(sav != NULL, ("null SA"));
ipcompx = sav->tdb_compalgxform;
IPSEC_ASSERT(ipcompx != NULL, ("null compression xform"));
/*
* Do not touch the packet in case our payload to compress
* is lower than the minimal threshold of the compression
* alogrithm. We will just send out the data uncompressed.
* See RFC 3173, 2.2. Non-Expansion Policy.
*/
if (m->m_pkthdr.len <= ipcompx->minlen) {
IPCOMPSTAT_INC(ipcomps_threshold);
return ipsec_process_done(m, sp, sav, idx);
}
ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
IPCOMPSTAT_INC(ipcomps_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:
IPCOMPSTAT_INC(ipcomps_nopf);
DPRINTF(("%s: unknown/unsupported protocol family %d, "
"IPCA %s/%08lx\n", __func__,
sav->sah->saidx.dst.sa.sa_family,
ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
(u_long) ntohl(sav->spi)));
error = EPFNOSUPPORT;
goto bad;
}
if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
IPCOMPSTAT_INC(ipcomps_toobig);
DPRINTF(("%s: packet in IPCA %s/%08lx got too big "
"(len %u, max len %u)\n", __func__,
ipsec_address(&sav->sah->saidx.dst, buf, sizeof(buf)),
(u_long) ntohl(sav->spi),
ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
error = EMSGSIZE;
goto bad;
}
/* Update the counters */
IPCOMPSTAT_ADD(ipcomps_obytes, m->m_pkthdr.len - skip);
m = m_unshare(m, M_NOWAIT);
if (m == NULL) {
IPCOMPSTAT_INC(ipcomps_hdrops);
DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
__func__, ipsec_address(&sav->sah->saidx.dst, buf,
sizeof(buf)), (u_long) ntohl(sav->spi)));
error = ENOBUFS;
goto bad;
}
/* Ok now, we can pass to the crypto processing. */
SECASVAR_LOCK(sav);
cryptoid = sav->tdb_cryptoid;
SECASVAR_UNLOCK(sav);
/* Get crypto descriptors */
crp = crypto_getreq(cryptoid, M_NOWAIT);
if (crp == NULL) {
IPCOMPSTAT_INC(ipcomps_crypto);
DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
error = ENOBUFS;
goto bad;
}
/* Compression descriptor */
crp->crp_op = CRYPTO_OP_COMPRESS;
crp->crp_payload_start = skip;
crp->crp_payload_length = ralen;
/* IPsec-specific opaque crypto info */
xd = malloc(sizeof(struct xform_data), M_IPCOMP, M_NOWAIT | M_ZERO);
if (xd == NULL) {
IPCOMPSTAT_INC(ipcomps_crypto);
DPRINTF(("%s: failed to allocate xform_data\n", __func__));
crypto_freereq(crp);
error = ENOBUFS;
goto bad;
}
xd->sp = sp;
xd->sav = sav;
xd->idx = idx;
xd->skip = skip;
xd->protoff = protoff;
xd->vnet = curvnet;
xd->cryptoid = cryptoid;
/* Crypto operation descriptor */
crp->crp_flags = CRYPTO_F_CBIFSYNC;
crypto_use_mbuf(crp, m);
crp->crp_callback = ipcomp_output_cb;
crp->crp_opaque = xd;
return crypto_dispatch(crp);
bad:
if (m)
m_freem(m);
key_freesav(&sav);
key_freesp(&sp);
return (error);
}
/*
* IPComp output callback from the crypto driver.
*/
static int
ipcomp_output_cb(struct cryptop *crp)
{
IPSEC_DEBUG_DECLARE(char buf[IPSEC_ADDRSTRLEN]);
struct xform_data *xd;
struct secpolicy *sp;
struct secasvar *sav;
struct mbuf *m;
crypto_session_t cryptoid;
u_int idx;
int error, skip, protoff;
m = crp->crp_buf.cb_mbuf;
xd = crp->crp_opaque;
CURVNET_SET(xd->vnet);
idx = xd->idx;
sp = xd->sp;
sav = xd->sav;
skip = xd->skip;
protoff = xd->protoff;
cryptoid = xd->cryptoid;
/* Check for crypto errors */
if (crp->crp_etype) {
if (crp->crp_etype == EAGAIN) {
/* Reset the session ID */
if (ipsec_updateid(sav, &crp->crp_session, &cryptoid) != 0)
crypto_freesession(cryptoid);
xd->cryptoid = crp->crp_session;
CURVNET_RESTORE();
return (crypto_dispatch(crp));
}
IPCOMPSTAT_INC(ipcomps_noxform);
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
IPCOMPSTAT_INC(ipcomps_crypto);
DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
error = EINVAL;
goto bad;
}
IPCOMPSTAT_INC(ipcomps_hist[sav->alg_comp]);
if (crp->crp_payload_length > crp->crp_olen) {
struct mbuf *mo;
struct ipcomp *ipcomp;
int roff;
uint8_t prot;
/* Compression helped, inject IPCOMP header. */
mo = m_makespace(m, skip, IPCOMP_HLENGTH, &roff);
if (mo == NULL) {
IPCOMPSTAT_INC(ipcomps_wrap);
DPRINTF(("%s: IPCOMP header inject failed "
"for IPCA %s/%08lx\n",
__func__, ipsec_address(&sav->sah->saidx.dst, buf,
sizeof(buf)), (u_long) ntohl(sav->spi)));
error = ENOBUFS;
goto bad;
}
ipcomp = (struct ipcomp *)(mtod(mo, caddr_t) + 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;
ipcomp->comp_cpi = htons((u_int16_t) ntohl(sav->spi));
/* Fix Next Protocol in IPv4/IPv6 header */
prot = IPPROTO_IPCOMP;
m_copyback(m, 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:
IPCOMPSTAT_INC(ipcomps_nopf);
DPRINTF(("%s: unknown/unsupported protocol "
"family %d, IPCA %s/%08lx\n", __func__,
sav->sah->saidx.dst.sa.sa_family,
ipsec_address(&sav->sah->saidx.dst, buf,
sizeof(buf)), (u_long) ntohl(sav->spi)));
error = EPFNOSUPPORT;
goto bad;
}
} else {
/* Compression was useless, we have lost time. */
IPCOMPSTAT_INC(ipcomps_uncompr);
DPRINTF(("%s: compressions was useless %d <= %d\n",
__func__, crp->crp_payload_length, crp->crp_olen));
/* XXX remember state to not compress the next couple
* of packets, RFC 3173, 2.2. Non-Expansion Policy */
}
/* Release the crypto descriptor */
free(xd, M_IPCOMP);
crypto_freereq(crp);
/* NB: m is reclaimed by ipsec_process_done. */
error = ipsec_process_done(m, sp, sav, idx);
CURVNET_RESTORE();
return (error);
bad:
if (m)
m_freem(m);
CURVNET_RESTORE();
free(xd, M_IPCOMP);
crypto_freereq(crp);
key_freesav(&sav);
key_freesp(&sp);
return (error);
}
#ifdef INET
static int
ipcomp4_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
void *arg __unused)
{
union sockaddr_union src, dst;
const struct ip *ip;
if (V_ipcomp_enable == 0)
return (0);
if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
return (0);
bzero(&src, sizeof(src));
bzero(&dst, sizeof(dst));
src.sa.sa_family = dst.sa.sa_family = AF_INET;
src.sin.sin_len = dst.sin.sin_len = sizeof(struct sockaddr_in);
ip = mtod(m, const struct ip *);
src.sin.sin_addr = ip->ip_src;
dst.sin.sin_addr = ip->ip_dst;
return (ipcomp_encapcheck(&src, &dst));
}
static const struct encaptab *ipe4_cookie = NULL;
static const struct encap_config ipv4_encap_cfg = {
.proto = -1,
.min_length = sizeof(struct ip),
.exact_match = sizeof(in_addr_t) << 4,
.check = ipcomp4_nonexp_encapcheck,
.input = ipcomp_nonexp_input
};
#endif
#ifdef INET6
static int
ipcomp6_nonexp_encapcheck(const struct mbuf *m, int off, int proto,
void *arg __unused)
{
union sockaddr_union src, dst;
const struct ip6_hdr *ip6;
if (V_ipcomp_enable == 0)
return (0);
if (proto != IPPROTO_IPV4 && proto != IPPROTO_IPV6)
return (0);
bzero(&src, sizeof(src));
bzero(&dst, sizeof(dst));
src.sa.sa_family = dst.sa.sa_family = AF_INET;
src.sin6.sin6_len = dst.sin6.sin6_len = sizeof(struct sockaddr_in6);
ip6 = mtod(m, const struct ip6_hdr *);
src.sin6.sin6_addr = ip6->ip6_src;
dst.sin6.sin6_addr = ip6->ip6_dst;
if (IN6_IS_SCOPE_LINKLOCAL(&src.sin6.sin6_addr)) {
/* XXX: sa6_recoverscope() */
src.sin6.sin6_scope_id =
ntohs(src.sin6.sin6_addr.s6_addr16[1]);
src.sin6.sin6_addr.s6_addr16[1] = 0;
}
if (IN6_IS_SCOPE_LINKLOCAL(&dst.sin6.sin6_addr)) {
/* XXX: sa6_recoverscope() */
dst.sin6.sin6_scope_id =
ntohs(dst.sin6.sin6_addr.s6_addr16[1]);
dst.sin6.sin6_addr.s6_addr16[1] = 0;
}
return (ipcomp_encapcheck(&src, &dst));
}
static const struct encaptab *ipe6_cookie = NULL;
static const struct encap_config ipv6_encap_cfg = {
.proto = -1,
.min_length = sizeof(struct ip6_hdr),
.exact_match = sizeof(struct in6_addr) << 4,
.check = ipcomp6_nonexp_encapcheck,
.input = ipcomp_nonexp_input
};
#endif
static struct xformsw ipcomp_xformsw = {
.xf_type = XF_IPCOMP,
.xf_name = "IPcomp",
.xf_init = ipcomp_init,
.xf_cleanup = ipcomp_cleanup,
.xf_input = ipcomp_input,
.xf_output = ipcomp_output,
};
static void
ipcomp_attach(void)
{
#ifdef INET
ipe4_cookie = ip_encap_attach(&ipv4_encap_cfg, NULL, M_WAITOK);
#endif
#ifdef INET6
ipe6_cookie = ip6_encap_attach(&ipv6_encap_cfg, NULL, M_WAITOK);
#endif
xform_attach(&ipcomp_xformsw);
}
static void
ipcomp_detach(void)
{
#ifdef INET
ip_encap_detach(ipe4_cookie);
#endif
#ifdef INET6
ip6_encap_detach(ipe6_cookie);
#endif
xform_detach(&ipcomp_xformsw);
}
SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
ipcomp_attach, NULL);
SYSUNINIT(ipcomp_xform_uninit, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
ipcomp_detach, NULL);
