freebsd-dev/sys/netipsec/xform_ipcomp.c
John Baldwin c034143269 Refactor driver and consumer interfaces for OCF (in-kernel crypto).
- The linked list of cryptoini structures used in session
  initialization is replaced with a new flat structure: struct
  crypto_session_params.  This session includes a new mode to define
  how the other fields should be interpreted.  Available modes
  include:

  - COMPRESS (for compression/decompression)
  - CIPHER (for simply encryption/decryption)
  - DIGEST (computing and verifying digests)
  - AEAD (combined auth and encryption such as AES-GCM and AES-CCM)
  - ETA (combined auth and encryption using encrypt-then-authenticate)

  Additional modes could be added in the future (e.g. if we wanted to
  support TLS MtE for AES-CBC in the kernel we could add a new mode
  for that.  TLS modes might also affect how AAD is interpreted, etc.)

  The flat structure also includes the key lengths and algorithms as
  before.  However, code doesn't have to walk the linked list and
  switch on the algorithm to determine which key is the auth key vs
  encryption key.  The 'csp_auth_*' fields are always used for auth
  keys and settings and 'csp_cipher_*' for cipher.  (Compression
  algorithms are stored in csp_cipher_alg.)

- Drivers no longer register a list of supported algorithms.  This
  doesn't quite work when you factor in modes (e.g. a driver might
  support both AES-CBC and SHA2-256-HMAC separately but not combined
  for ETA).  Instead, a new 'crypto_probesession' method has been
  added to the kobj interface for symmteric crypto drivers.  This
  method returns a negative value on success (similar to how
  device_probe works) and the crypto framework uses this value to pick
  the "best" driver.  There are three constants for hardware
  (e.g. ccr), accelerated software (e.g. aesni), and plain software
  (cryptosoft) that give preference in that order.  One effect of this
  is that if you request only hardware when creating a new session,
  you will no longer get a session using accelerated software.
  Another effect is that the default setting to disallow software
  crypto via /dev/crypto now disables accelerated software.

  Once a driver is chosen, 'crypto_newsession' is invoked as before.

- Crypto operations are now solely described by the flat 'cryptop'
  structure.  The linked list of descriptors has been removed.

  A separate enum has been added to describe the type of data buffer
  in use instead of using CRYPTO_F_* flags to make it easier to add
  more types in the future if needed (e.g. wired userspace buffers for
  zero-copy).  It will also make it easier to re-introduce separate
  input and output buffers (in-kernel TLS would benefit from this).

  Try to make the flags related to IV handling less insane:

  - CRYPTO_F_IV_SEPARATE means that the IV is stored in the 'crp_iv'
    member of the operation structure.  If this flag is not set, the
    IV is stored in the data buffer at the 'crp_iv_start' offset.

  - CRYPTO_F_IV_GENERATE means that a random IV should be generated
    and stored into the data buffer.  This cannot be used with
    CRYPTO_F_IV_SEPARATE.

  If a consumer wants to deal with explicit vs implicit IVs, etc. it
  can always generate the IV however it needs and store partial IVs in
  the buffer and the full IV/nonce in crp_iv and set
  CRYPTO_F_IV_SEPARATE.

  The layout of the buffer is now described via fields in cryptop.
  crp_aad_start and crp_aad_length define the boundaries of any AAD.
  Previously with GCM and CCM you defined an auth crd with this range,
  but for ETA your auth crd had to span both the AAD and plaintext
  (and they had to be adjacent).

  crp_payload_start and crp_payload_length define the boundaries of
  the plaintext/ciphertext.  Modes that only do a single operation
  (COMPRESS, CIPHER, DIGEST) should only use this region and leave the
  AAD region empty.

  If a digest is present (or should be generated), it's starting
  location is marked by crp_digest_start.

  Instead of using the CRD_F_ENCRYPT flag to determine the direction
  of the operation, cryptop now includes an 'op' field defining the
  operation to perform.  For digests I've added a new VERIFY digest
  mode which assumes a digest is present in the input and fails the
  request with EBADMSG if it doesn't match the internally-computed
  digest.  GCM and CCM already assumed this, and the new AEAD mode
  requires this for decryption.  The new ETA mode now also requires
  this for decryption, so IPsec and GELI no longer do their own
  authentication verification.  Simple DIGEST operations can also do
  this, though there are no in-tree consumers.

  To eventually support some refcounting to close races, the session
  cookie is now passed to crypto_getop() and clients should no longer
  set crp_sesssion directly.

- Assymteric crypto operation structures should be allocated via
  crypto_getkreq() and freed via crypto_freekreq().  This permits the
  crypto layer to track open asym requests and close races with a
  driver trying to unregister while asym requests are in flight.

- crypto_copyback, crypto_copydata, crypto_apply, and
  crypto_contiguous_subsegment now accept the 'crp' object as the
  first parameter instead of individual members.  This makes it easier
  to deal with different buffer types in the future as well as
  separate input and output buffers.  It's also simpler for driver
  writers to use.

- bus_dmamap_load_crp() loads a DMA mapping for a crypto buffer.
  This understands the various types of buffers so that drivers that
  use DMA do not have to be aware of different buffer types.

- Helper routines now exist to build an auth context for HMAC IPAD
  and OPAD.  This reduces some duplicated work among drivers.

- Key buffers are now treated as const throughout the framework and in
  device drivers.  However, session key buffers provided when a session
  is created are expected to remain alive for the duration of the
  session.

- GCM and CCM sessions now only specify a cipher algorithm and a cipher
  key.  The redundant auth information is not needed or used.

- For cryptosoft, split up the code a bit such that the 'process'
  callback now invokes a function pointer in the session.  This
  function pointer is set based on the mode (in effect) though it
  simplifies a few edge cases that would otherwise be in the switch in
  'process'.

  It does split up GCM vs CCM which I think is more readable even if there
  is some duplication.

- I changed /dev/crypto to support GMAC requests using CRYPTO_AES_NIST_GMAC
  as an auth algorithm and updated cryptocheck to work with it.

- Combined cipher and auth sessions via /dev/crypto now always use ETA
  mode.  The COP_F_CIPHER_FIRST flag is now a no-op that is ignored.
  This was actually documented as being true in crypto(4) before, but
  the code had not implemented this before I added the CIPHER_FIRST
  flag.

- I have not yet updated /dev/crypto to be aware of explicit modes for
  sessions.  I will probably do that at some point in the future as well
  as teach it about IV/nonce and tag lengths for AEAD so we can support
  all of the NIST KAT tests for GCM and CCM.

- I've split up the exising crypto.9 manpage into several pages
  of which many are written from scratch.

- I have converted all drivers and consumers in the tree and verified
  that they compile, but I have not tested all of them.  I have tested
  the following drivers:

  - cryptosoft
  - aesni (AES only)
  - blake2
  - ccr

  and the following consumers:

  - cryptodev
  - IPsec
  - ktls_ocf
  - GELI (lightly)

  I have not tested the following:

  - ccp
  - aesni with sha
  - hifn
  - kgssapi_krb5
  - ubsec
  - padlock
  - safe
  - armv8_crypto (aarch64)
  - glxsb (i386)
  - sec (ppc)
  - cesa (armv7)
  - cryptocteon (mips64)
  - nlmsec (mips64)

Discussed with:	cem
Relnotes:	yes
Sponsored by:	Chelsio Communications
Differential Revision:	https://reviews.freebsd.org/D23677
2020-03-27 18:25:23 +00:00

780 lines
20 KiB
C

/* $FreeBSD$ */
/* $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 <sys/param.h>
#include <sys/systm.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 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_zeroize() used when IPCA is deleted
*/
static int
ipcomp_zeroize(struct secasvar *sav)
{
crypto_freesession(sav->tdb_cryptoid);
sav->tdb_cryptoid = NULL;
return 0;
}
/*
* 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_XDATA, 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_ilen = m->m_pkthdr.len - (skip + hlen);
crp->crp_flags = CRYPTO_F_CBIFSYNC;
crp->crp_mbuf = m;
crp->crp_buf_type = CRYPTO_BUF_MBUF;
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_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_XDATA), 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_XDATA);
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_XDATA, 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_ilen = m->m_pkthdr.len; /* Total input length */
crp->crp_flags = CRYPTO_F_CBIFSYNC;
crp->crp_mbuf = m;
crp->crp_buf_type = CRYPTO_BUF_MBUF;
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_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_XDATA);
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_XDATA);
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_zeroize = ipcomp_zeroize,
.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);