/* $FreeBSD$ */
/* $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.
*/
/* IP payload compression protocol (IPComp), see RFC 2393 */
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/rwlock.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 <net/route.h>
#include <net/vnet.h>
#include <netipsec/ipsec.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 <opencrypto/cryptodev.h>
#include <opencrypto/deflate.h>
#include <opencrypto/xform.h>
VNET_DEFINE(int, ipcomp_enable) = 1;
VNET_DEFINE(struct ipcompstat, ipcompstat);
SYSCTL_DECL(_net_inet_ipcomp);
SYSCTL_VNET_INT(_net_inet_ipcomp, OID_AUTO,
ipcomp_enable, CTLFLAG_RW, &VNET_NAME(ipcomp_enable), 0, "");
SYSCTL_VNET_STRUCT(_net_inet_ipcomp, IPSECCTL_STATS,
stats, CTLFLAG_RD, &VNET_NAME(ipcompstat), ipcompstat, "");
static int ipcomp_input_cb(struct cryptop *crp);
static int ipcomp_output_cb(struct cryptop *crp);
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;
}
return NULL;
}
/*
* ipcomp_init() is called when an CPI is being set up.
*/
static int
ipcomp_init(struct secasvar *sav, struct xformsw *xsp)
{
struct comp_algo *tcomp;
struct cryptoini cric;
/* NB: algorithm really comes in alg_enc and not alg_comp! */
tcomp = ipcomp_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 */
bzero(&cric, sizeof (cric));
cric.cri_alg = sav->tdb_compalgxform->type;
return crypto_newsession(&sav->tdb_cryptoid, &cric, V_crypto_support);
}
/*
* 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, struct secasvar *sav, int skip, int protoff)
{
struct tdb_crypto *tc;
struct cryptodesc *crdc;
struct cryptop *crp;
struct ipcomp *ipcomp;
caddr_t addr;
int 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.
*/
if (m->m_len < skip + hlen && (m = m_pullup(m, skip + hlen)) == NULL) {
V_ipcompstat.ipcomps_hdrops++; /*XXX*/
DPRINTF(("%s: m_pullup failed\n", __func__));
return (ENOBUFS);
}
addr = (caddr_t) mtod(m, struct ip *) + skip;
ipcomp = (struct ipcomp *)addr;
if (ipcomp->comp_nxt == IPPROTO_IPCOMP) {
m_freem(m);
V_ipcompstat.ipcomps_pdrops++; /* XXX have our own stats? */
DPRINTF(("%s: recursive compression detected\n", __func__));
return (EINVAL);
}
/* Get crypto descriptors */
crp = crypto_getreq(1);
if (crp == NULL) {
m_freem(m);
DPRINTF(("%s: no crypto descriptors\n", __func__));
V_ipcompstat.ipcomps_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(("%s: cannot allocate tdb_crypto\n", __func__));
V_ipcompstat.ipcomps_crypto++;
return ENOBUFS;
}
crdc = crp->crp_desc;
crdc->crd_skip = skip + hlen;
crdc->crd_len = m->m_pkthdr.len - (skip + hlen);
crdc->crd_inject = skip;
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_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
crp->crp_buf = (caddr_t) m;
crp->crp_callback = ipcomp_input_cb;
crp->crp_sid = sav->tdb_cryptoid;
crp->crp_opaque = (caddr_t) 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;
KEY_ADDREFSA(sav);
tc->tc_sav = sav;
return crypto_dispatch(crp);
}
/*
* 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 hlen = IPCOMP_HLENGTH, error, clen;
u_int8_t nproto;
caddr_t addr;
crd = crp->crp_desc;
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("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;
sav = tc->tc_sav;
IPSEC_ASSERT(sav != NULL, ("null SA!"));
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) {
/* Reset the session ID */
if (sav->tdb_cryptoid != 0)
sav->tdb_cryptoid = crp->crp_sid;
if (crp->crp_etype == EAGAIN) {
return crypto_dispatch(crp);
}
V_ipcompstat.ipcomps_noxform++;
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
V_ipcompstat.ipcomps_crypto++;
DPRINTF(("%s: null mbuf returned from crypto\n", __func__));
error = EINVAL;
goto bad;
}
V_ipcompstat.ipcomps_hist[sav->alg_comp]++;
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) {
V_ipcompstat.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) {
V_ipcompstat.ipcomps_hdrops++;
DPRINTF(("%s: bad mbuf chain, IPCA %s/%08lx\n", __func__,
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);
switch (saidx->dst.sa.sa_family) {
#ifdef INET6
case AF_INET6:
error = ipsec6_common_input_cb(m, sav, skip, protoff, NULL);
break;
#endif
#ifdef INET
case AF_INET:
error = ipsec4_common_input_cb(m, sav, skip, protoff, NULL);
break;
#endif
default:
panic("%s: Unexpected address family: %d saidx=%p", __func__,
saidx->dst.sa.sa_family, saidx);
}
KEY_FREESAV(&sav);
return error;
bad:
if (sav)
KEY_FREESAV(&sav);
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
)
{
struct secasvar *sav;
struct comp_algo *ipcompx;
int error, ralen, maxpacketsize;
struct cryptodesc *crdc;
struct cryptop *crp;
struct tdb_crypto *tc;
sav = isr->sav;
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) {
V_ipcompstat.ipcomps_threshold++;
return ipsec_process_done(m, isr);
}
ralen = m->m_pkthdr.len - skip; /* Raw payload length before comp. */
V_ipcompstat.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:
V_ipcompstat.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),
(u_long) ntohl(sav->spi)));
error = EPFNOSUPPORT;
goto bad;
}
if (ralen + skip + IPCOMP_HLENGTH > maxpacketsize) {
V_ipcompstat.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),
(u_long) ntohl(sav->spi),
ralen + skip + IPCOMP_HLENGTH, maxpacketsize));
error = EMSGSIZE;
goto bad;
}
/* Update the counters */
V_ipcompstat.ipcomps_obytes += m->m_pkthdr.len - skip;
m = m_unshare(m, M_NOWAIT);
if (m == NULL) {
V_ipcompstat.ipcomps_hdrops++;
DPRINTF(("%s: cannot clone mbuf chain, IPCA %s/%08lx\n",
__func__, 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) {
V_ipcompstat.ipcomps_crypto++;
DPRINTF(("%s: failed to acquire crypto descriptor\n",__func__));
error = ENOBUFS;
goto bad;
}
crdc = crp->crp_desc;
/* Compression descriptor */
crdc->crd_skip = skip;
crdc->crd_len = ralen;
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) {
V_ipcompstat.ipcomps_crypto++;
DPRINTF(("%s: failed to allocate tdb_crypto\n", __func__));
crypto_freereq(crp);
error = ENOBUFS;
goto bad;
}
tc->tc_isr = isr;
KEY_ADDREFSA(sav);
tc->tc_sav = sav;
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;
/* Crypto operation descriptor */
crp->crp_ilen = m->m_pkthdr.len; /* Total input length */
crp->crp_flags = CRYPTO_F_IMBUF | CRYPTO_F_CBIFSYNC;
crp->crp_buf = (caddr_t) m;
crp->crp_callback = ipcomp_output_cb;
crp->crp_opaque = (caddr_t) 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;
int error, skip;
tc = (struct tdb_crypto *) crp->crp_opaque;
IPSEC_ASSERT(tc != NULL, ("null opaque data area!"));
m = (struct mbuf *) crp->crp_buf;
skip = tc->tc_skip;
isr = tc->tc_isr;
IPSECREQUEST_LOCK(isr);
sav = tc->tc_sav;
/* With the isr lock released SA pointer can be updated. */
if (sav != isr->sav) {
V_ipcompstat.ipcomps_notdb++;
DPRINTF(("%s: SA expired while in crypto\n", __func__));
error = ENOBUFS; /*XXX*/
goto bad;
}
/* 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) {
IPSECREQUEST_UNLOCK(isr);
return crypto_dispatch(crp);
}
V_ipcompstat.ipcomps_noxform++;
DPRINTF(("%s: crypto error %d\n", __func__, crp->crp_etype));
error = crp->crp_etype;
goto bad;
}
/* Shouldn't happen... */
if (m == NULL) {
V_ipcompstat.ipcomps_crypto++;
DPRINTF(("%s: bogus return buffer from crypto\n", __func__));
error = EINVAL;
goto bad;
}
V_ipcompstat.ipcomps_hist[sav->alg_comp]++;
if (crp->crp_ilen - skip > 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) {
V_ipcompstat.ipcomps_wrap++;
DPRINTF(("%s: IPCOMP header inject failed for IPCA %s/%08lx\n",
__func__, ipsec_address(&sav->sah->saidx.dst),
(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, 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:
V_ipcompstat.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),
(u_long) ntohl(sav->spi)));
error = EPFNOSUPPORT;
goto bad;
}
} else {
/* Compression was useless, we have lost time. */
V_ipcompstat.ipcomps_uncompr++;
DPRINTF(("%s: compressions was useless %d - %d <= %d\n",
__func__, crp->crp_ilen, skip, 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(tc, M_XDATA);
crypto_freereq(crp);
/* NB: m is reclaimed by ipsec_process_done. */
error = ipsec_process_done(m, isr);
KEY_FREESAV(&sav);
IPSECREQUEST_UNLOCK(isr);
return error;
bad:
if (sav)
KEY_FREESAV(&sav);
IPSECREQUEST_UNLOCK(isr);
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
};
static void
ipcomp_attach(void)
{
xform_register(&ipcomp_xformsw);
}
SYSINIT(ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE, ipcomp_attach, NULL);
static void
vnet_ipcomp_attach(const void *unused __unused)
{
V_ipcompstat.version = IPCOMPSTAT_VERSION;
}
VNET_SYSINIT(vnet_ipcomp_xform_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_MIDDLE,
vnet_ipcomp_attach, NULL);
