NetBSD/sys/netinet6/esp_core.c

1264 lines
29 KiB
C

/* $NetBSD: esp_core.c,v 1.3 2000/07/23 05:23:04 itojun Exp $ */
/* $KAME: esp_core.c,v 1.20 2000/07/21 02:42:12 itojun 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 "opt_inet.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/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#ifdef INET6
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet/icmp6.h>
#endif
#include <netinet6/ipsec.h>
#include <netinet6/ah.h>
#include <netinet6/esp.h>
#include <net/pfkeyv2.h>
#include <netkey/keydb.h>
#include <crypto/des/des.h>
#include <crypto/blowfish/blowfish.h>
#include <crypto/cast128/cast128.h>
#ifdef SADB_X_EALG_RC5CBC
#include <crypto/rc5/rc5.h>
#endif
#include <net/net_osdep.h>
static int esp_crypto_sanity __P((const struct esp_algorithm *,
struct secasvar *, int));
static int esp_null_mature __P((struct secasvar *));
static int esp_null_ivlen __P((struct secasvar *));
static int esp_null_decrypt __P((struct mbuf *, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_null_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_descbc_mature __P((struct secasvar *));
static int esp_descbc_ivlen __P((struct secasvar *));
static int esp_descbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_descbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_descbc_schedule __P((const struct esp_algorithm *,
struct secasvar *));
static int esp_cbc_mature __P((struct secasvar *));
static int esp_blowfish_cbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_blowfish_cbc_encrypt __P((struct mbuf *, size_t,
size_t, struct secasvar *, const struct esp_algorithm *, int));
static int esp_blowfish_cbc_schedule __P((const struct esp_algorithm *,
struct secasvar *));
static int esp_blowfish_cbc_ivlen __P((struct secasvar *));
static int esp_cast128cbc_ivlen __P((struct secasvar *));
static int esp_cast128cbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_cast128cbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_cast128cbc_schedule __P((const struct esp_algorithm *,
struct secasvar *));
static int esp_3descbc_ivlen __P((struct secasvar *));
static int esp_3descbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_3descbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_3descbc_schedule __P((const struct esp_algorithm *,
struct secasvar *));
#ifdef SADB_X_EALG_RC5CBC
static int esp_rc5cbc_ivlen __P((struct secasvar *));
static int esp_rc5cbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_rc5cbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, const struct esp_algorithm *, int));
static int esp_rc5cbc_schedule __P((const struct esp_algorithm *,
struct secasvar *));
#endif
static void esp_increment_iv __P((struct secasvar *));
static caddr_t mbuf_find_offset __P((struct mbuf *, size_t, size_t));
const struct esp_algorithm *
esp_algorithm_lookup(idx)
int idx;
{
static struct esp_algorithm esp_algorithms[] = {
{ 8, esp_descbc_mature, 64, 64, sizeof(des_key_schedule),
"des-cbc",
esp_descbc_ivlen, esp_descbc_decrypt,
esp_descbc_encrypt, esp_descbc_schedule, },
{ 8, esp_cbc_mature, 192, 192, sizeof(des_key_schedule) * 3,
"3des-cbc",
esp_3descbc_ivlen, esp_3descbc_decrypt,
esp_3descbc_encrypt, esp_3descbc_schedule, },
{ 1, esp_null_mature, 0, 2048, 0, "null",
esp_null_ivlen, esp_null_decrypt,
esp_null_encrypt, NULL, },
{ 8, esp_cbc_mature, 40, 448, sizeof(BF_KEY), "blowfish-cbc",
esp_blowfish_cbc_ivlen, esp_blowfish_cbc_decrypt,
esp_blowfish_cbc_encrypt, esp_blowfish_cbc_schedule, },
{ 8, esp_cbc_mature, 40, 128, sizeof(u_int32_t) * 32,
"cast128-cbc",
esp_cast128cbc_ivlen, esp_cast128cbc_decrypt,
esp_cast128cbc_encrypt, esp_cast128cbc_schedule, },
#ifdef SADB_X_EALG_RC5CBC
{ 8, esp_cbc_mature, 40, 2040, sizeof(RC5_WORD) * 34, "rc5-cbc",
esp_rc5cbc_ivlen, esp_rc5cbc_decrypt,
esp_rc5cbc_encrypt, esp_rc5cbc_schedule, },
#else
{ 8, NULL, 40, 2040, 0, "rc5-cbc dummy",
NULL, NULL, NULL, NULL, },
#endif
};
switch (idx) {
case SADB_EALG_DESCBC:
return &esp_algorithms[0];
case SADB_EALG_3DESCBC:
return &esp_algorithms[1];
case SADB_EALG_NULL:
return &esp_algorithms[2];
case SADB_X_EALG_BLOWFISHCBC:
return &esp_algorithms[3];
case SADB_X_EALG_CAST128CBC:
return &esp_algorithms[4];
#ifdef SADB_X_EALG_RC5CBC
case SADB_X_EALG_RC5CBC:
return &esp_algorithms[5];
#endif
default:
return NULL;
}
}
int
esp_schedule(algo, sav)
const struct esp_algorithm *algo;
struct secasvar *sav;
{
if (_KEYBITS(sav->key_enc) < algo->keymin ||
_KEYBITS(sav->key_enc) > algo->keymax) {
ipseclog((LOG_ERR,
"esp_schedule %s: unsupported key length %d: "
"needs %d to %d bits\n", algo->name, _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax));
return EINVAL;
}
if (!algo->schedule || algo->schedlen == 0)
return 0;
if (!sav->sched || sav->schedlen != algo->schedlen)
panic("invalid sav->schedlen in esp_schedule");
return (*algo->schedule)(algo, sav);
}
/*
* default sanity check for algo->{de,en}crypt
*/
static int
esp_crypto_sanity(algo, sav, ivlen)
const struct esp_algorithm *algo;
struct secasvar *sav;
int ivlen;
{
if (sav->ivlen != ivlen) {
ipseclog((LOG_ERR, "esp_decrypt %s: bad ivlen %d/%d\n",
algo->name, ivlen, sav->ivlen));
return EINVAL;
}
if (!sav->sched || sav->schedlen != algo->schedlen) {
ipseclog((LOG_ERR,
"esp_decrypt %s: no intermediate key\n", algo->name));
return EINVAL;
}
return 0;
}
/*
* mbuf assumption: foo_encrypt() assumes that IV part is placed in a single
* mbuf, not across multiple mbufs.
*/
static int
esp_null_mature(sav)
struct secasvar *sav;
{
/* anything is okay */
return 0;
}
static int
esp_null_ivlen(sav)
struct secasvar *sav;
{
return 0;
}
static int
esp_null_decrypt(m, off, sav, algo, ivlen)
struct mbuf *m;
size_t off; /* offset to ESP header */
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
return 0; /* do nothing */
}
static int
esp_null_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off; /* offset to ESP header */
size_t plen; /* payload length (to be encrypted) */
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
return 0; /* do nothing */
}
static int
esp_descbc_mature(sav)
struct secasvar *sav;
{
const struct esp_algorithm *algo;
if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B)) {
ipseclog((LOG_ERR, "esp_cbc_mature: "
"algorithm incompatible with 4 octets IV length\n"));
return 1;
}
if (!sav->key_enc) {
ipseclog((LOG_ERR, "esp_descbc_mature: no key is given.\n"));
return 1;
}
algo = esp_algorithm_lookup(sav->alg_enc);
if (!algo) {
ipseclog((LOG_ERR,
"esp_descbc_mature: unsupported algorithm.\n"));
return 1;
}
if (_KEYBITS(sav->key_enc) < algo->keymin ||
_KEYBITS(sav->key_enc) > algo->keymax) {
ipseclog((LOG_ERR,
"esp_descbc_mature: invalid key length %d.\n",
_KEYBITS(sav->key_enc)));
return 1;
}
/* weak key check */
if (des_is_weak_key((C_Block *)_KEYBUF(sav->key_enc))) {
ipseclog((LOG_ERR,
"esp_descbc_mature: weak key was passed.\n"));
return 1;
}
return 0;
}
static int
esp_descbc_ivlen(sav)
struct secasvar *sav;
{
if (!sav)
return 8;
if ((sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B))
return 4;
if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_DERIV))
return 4;
return 8;
}
static int
esp_descbc_decrypt(m, off, sav, algo, ivlen)
struct mbuf *m;
size_t off; /* offset to ESP header */
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff = 0;
size_t bodyoff = 0;
u_int8_t *iv;
size_t plen;
u_int8_t tiv[8];
int derived;
int error;
derived = 0;
/* sanity check */
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1827 */
ivoff = off + sizeof(struct esp);
bodyoff = off + sizeof(struct esp) + ivlen;
derived = 0;
} else {
/* RFC 2406 */
if (sav->flags & SADB_X_EXT_DERIV) {
/*
* draft-ietf-ipsec-ciph-des-derived-00.txt
* uses sequence number field as IV field.
* This draft has been deleted, but you can get from
* ftp://ftp.kame.net/pub/internet-drafts/.
*/
ivoff = off + sizeof(struct esp);
bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
ivlen = sizeof(u_int32_t);
derived = 1;
} else {
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
derived = 0;
}
}
if (ivlen == 4) {
iv = &tiv[0];
m_copydata(m, ivoff, 4, &tiv[0]);
m_copydata(m, ivoff, 4, &tiv[4]);
tiv[4] ^= 0xff;
tiv[5] ^= 0xff;
tiv[6] ^= 0xff;
tiv[7] ^= 0xff;
} else if (ivlen == 8) {
iv = &tiv[0];
m_copydata(m, ivoff, 8, &tiv[0]);
} else {
ipseclog((LOG_ERR, "esp_descbc_decrypt: unsupported ivlen %d\n",
ivlen));
return EINVAL;
}
plen = m->m_pkthdr.len;
if (plen < bodyoff)
panic("esp_descbc_decrypt: too short packet: len=%lu",
(u_long)plen);
plen -= bodyoff;
if (plen % 8) {
ipseclog((LOG_ERR, "esp_descbc_decrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
error = des_cbc_encrypt(m, bodyoff, plen,
*(des_key_schedule *)sav->sched, (C_Block *)iv, DES_DECRYPT);
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return error;
}
static int
esp_descbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off; /* offset to ESP header */
size_t plen; /* payload length (to be decrypted) */
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff = 0;
size_t bodyoff = 0;
u_int8_t *iv;
u_int8_t tiv[8];
int derived;
int error;
derived = 0;
/* sanity check */
if (plen % 8) {
ipseclog((LOG_ERR, "esp_descbc_encrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1827 */
/*
* draft-ietf-ipsec-ciph-des-derived-00.txt
* uses sequence number field as IV field.
*/
ivoff = off + sizeof(struct esp);
bodyoff = off + sizeof(struct esp) + ivlen;
derived = 0;
} else {
/* RFC 2406 */
if (sav->flags & SADB_X_EXT_DERIV) {
/*
* draft-ietf-ipsec-ciph-des-derived-00.txt
* uses sequence number field as IV field.
*/
ivoff = off + sizeof(struct esp);
bodyoff = off + sizeof(struct esp) + sizeof(u_int32_t);
ivlen = sizeof(u_int32_t);
derived = 1;
} else {
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
derived = 0;
}
}
if (m->m_pkthdr.len < bodyoff)
panic("assumption failed: mbuf too short");
iv = mbuf_find_offset(m, ivoff, ivlen);
if (!iv)
panic("assumption failed: bad mbuf chain");
if (ivlen == 4) {
if (!derived) {
bcopy(sav->iv, &tiv[0], 4);
bcopy(sav->iv, &tiv[4], 4);
tiv[4] ^= 0xff;
tiv[5] ^= 0xff;
tiv[6] ^= 0xff;
tiv[7] ^= 0xff;
bcopy(&tiv[0], iv, 4);
iv = &tiv[0];
} else {
bcopy(iv, &tiv[0], 4);
bcopy(iv, &tiv[4], 4);
tiv[4] ^= 0xff;
tiv[5] ^= 0xff;
tiv[6] ^= 0xff;
tiv[7] ^= 0xff;
iv = &tiv[0];
}
} else if (ivlen == 8)
bcopy((caddr_t)sav->iv, (caddr_t)iv, ivlen);
else {
ipseclog((LOG_ERR,
"esp_descbc_encrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = des_cbc_encrypt(m, bodyoff, plen,
*(des_key_schedule *)sav->sched, (C_Block *)iv, DES_ENCRYPT);
esp_increment_iv(sav);
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return error;
}
static int
esp_descbc_schedule(algo, sav)
const struct esp_algorithm *algo;
struct secasvar *sav;
{
if (des_key_sched((C_Block *)_KEYBUF(sav->key_enc),
*(des_key_schedule *)sav->sched))
return EINVAL;
else
return 0;
}
static int
esp_cbc_mature(sav)
struct secasvar *sav;
{
int keylen;
const struct esp_algorithm *algo;
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_cbc_mature: algorithm incompatible with esp-old\n"));
return 1;
}
if (sav->flags & SADB_X_EXT_DERIV) {
ipseclog((LOG_ERR,
"esp_cbc_mature: algorithm incompatible with derived\n"));
return 1;
}
if (!sav->key_enc) {
ipseclog((LOG_ERR, "esp_cbc_mature: no key is given.\n"));
return 1;
}
algo = esp_algorithm_lookup(sav->alg_enc);
if (!algo) {
ipseclog((LOG_ERR,
"esp_cbc_mature %s: unsupported algorithm.\n", algo->name));
return 1;
}
keylen = sav->key_enc->sadb_key_bits;
if (keylen < algo->keymin || algo->keymax < keylen) {
ipseclog((LOG_ERR,
"esp_cbc_mature %s: invalid key length %d.\n",
algo->name, sav->key_enc->sadb_key_bits));
return 1;
}
switch (sav->alg_enc) {
case SADB_EALG_3DESCBC:
/* weak key check */
if (des_is_weak_key((C_Block *)_KEYBUF(sav->key_enc))
|| des_is_weak_key((C_Block *)(_KEYBUF(sav->key_enc) + 8))
|| des_is_weak_key((C_Block *)(_KEYBUF(sav->key_enc) + 16))) {
ipseclog((LOG_ERR,
"esp_cbc_mature %s: weak key was passed.\n",
algo->name));
return 1;
}
break;
case SADB_X_EALG_BLOWFISHCBC:
case SADB_X_EALG_CAST128CBC:
#ifdef SADB_X_EALG_RC5CBC
case SADB_X_EALG_RC5CBC:
#endif
break;
}
return 0;
}
static int
esp_blowfish_cbc_decrypt(m, off, sav, algo, ivlen)
struct mbuf *m;
size_t off; /* offset to ESP header */
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
u_int8_t tiv[8];
size_t plen;
int error;
/* sanity check */
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_blowfish_cbc_decrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR,
"esp_blowfish_cbc_decrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
iv = &tiv[0];
m_copydata(m, ivoff, 8, &tiv[0]);
plen = m->m_pkthdr.len;
if (plen < bodyoff)
panic("esp_blowfish_cbc_decrypt: too short packet: len=%lu",
(u_long)plen);
plen -= bodyoff;
if (plen % 8) {
ipseclog((LOG_ERR, "esp_blowfish_cbc_decrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
error = BF_cbc_encrypt_m(m, bodyoff, plen, (BF_KEY *)sav->sched, iv,
BF_DECRYPT);
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return error;
}
static int
esp_blowfish_cbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off; /* offset to ESP header */
size_t plen; /* payload length (to be decrypted) */
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
int error;
/* sanity check */
if (plen % 8) {
ipseclog((LOG_ERR, "esp_blowfish_cbc_encrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_blowfish_cbc_encrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR,
"esp_blowfish_cbc_encrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
if (m->m_pkthdr.len < bodyoff)
panic("assumption failed: mbuf too short");
iv = mbuf_find_offset(m, ivoff, ivlen);
if (!iv)
panic("assumption failed: bad mbuf chain");
bcopy((caddr_t)sav->iv, (caddr_t)iv, ivlen);
error = BF_cbc_encrypt_m(m, bodyoff, plen, (BF_KEY *)sav->sched, iv,
BF_ENCRYPT);
esp_increment_iv(sav);
return error;
}
static int
esp_blowfish_cbc_schedule(algo, sav)
const struct esp_algorithm *algo;
struct secasvar *sav;
{
BF_set_key((BF_KEY *)sav->sched, _KEYLEN(sav->key_enc),
_KEYBUF(sav->key_enc));
return 0;
}
static int
esp_blowfish_cbc_ivlen(sav)
struct secasvar *sav;
{
return 8;
}
static int
esp_cast128cbc_ivlen(sav)
struct secasvar *sav;
{
return 8;
}
static int
esp_cast128cbc_decrypt(m, off, sav, algo, ivlen)
struct mbuf *m;
size_t off;
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t iv[8];
size_t plen;
int error;
/* sanity check */
if (_KEYBITS(sav->key_enc) < algo->keymin ||
_KEYBITS(sav->key_enc) > algo->keymax) {
ipseclog((LOG_ERR,
"esp_cast128cbc_decrypt: unsupported key length %d: "
"needs %d to %d bits\n", _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_cast128cbc_decrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR,
"esp_cast128cbc_decrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
/* copy mbuf's IV into iv */
m_copydata(m, ivoff, 8, iv);
plen = m->m_pkthdr.len;
if (plen < bodyoff) {
panic("esp_cast128cbc_decrypt: too short packet: len=%lu\n",
(u_long)plen);
}
plen -= bodyoff;
if (plen % 8) {
ipseclog((LOG_ERR, "esp_cast128cbc_decrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
/* decrypt */
error = cast128_cbc_process(m, bodyoff, plen, (u_int32_t *)sav->sched,
iv, _KEYLEN(sav->key_enc), CAST128_DECRYPT);
return error;
}
static int
esp_cast128cbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off;
size_t plen;
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
int error;
/* sanity check */
if (plen % 8) {
ipseclog((LOG_ERR, "esp_cast128cbc_encrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin ||
_KEYBITS(sav->key_enc) > algo->keymax) {
ipseclog((LOG_ERR,
"esp_cast128cbc_encrypt: unsupported key length %d: "
"needs %d to %d bits\n", _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_cast128cbc_encrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR,
"esp_cast128cbc_encrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
if (m->m_pkthdr.len < bodyoff)
panic("assumption failed: mbuf too short");
iv = mbuf_find_offset(m, ivoff, ivlen);
if (!iv)
panic("assumption failed: bad mbuf chain");
bcopy(sav->iv, iv, ivlen);
/* encrypt */
error = cast128_cbc_process(m, bodyoff, plen, (u_int32_t *)sav->sched,
iv, _KEYLEN(sav->key_enc), CAST128_ENCRYPT);
esp_increment_iv(sav);
return error;
}
static int
esp_cast128cbc_schedule(algo, sav)
const struct esp_algorithm *algo;
struct secasvar *sav;
{
set_cast128_subkey((u_int32_t *)sav->sched, _KEYBUF(sav->key_enc));
return 0;
}
static int
esp_3descbc_ivlen(sav)
struct secasvar *sav;
{
return 8;
}
static int
esp_3descbc_decrypt(m, off, sav, algo, ivlen)
struct mbuf *m;
size_t off;
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
size_t plen;
u_int8_t tiv[8];
int error;
/* sanity check */
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_3descbc_decrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR,
"esp_3descbc_decrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
iv = &tiv[0];
m_copydata(m, ivoff, 8, &tiv[0]);
plen = m->m_pkthdr.len;
if (plen < bodyoff)
panic("esp_3descbc_decrypt: too short packet: len=%lu",
(u_long)plen);
plen -= bodyoff;
if (plen % 8) {
ipseclog((LOG_ERR, "esp_3descbc_decrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
/* decrypt packet */
des_3cbc_process(m, bodyoff, plen, (des_key_schedule *)sav->sched,
(C_Block *)iv, DES_DECRYPT);
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return 0;
}
static int
esp_3descbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off;
size_t plen;
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
int error;
/* sanity check */
if (plen % 8) {
ipseclog((LOG_ERR, "esp_3descbc_encrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_3descbc_encrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR,
"esp_3descbc_encrypt: unsupported ivlen %d\n", ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
if (m->m_pkthdr.len < bodyoff)
panic("assumption failed: mbuf too short");
iv = mbuf_find_offset(m, ivoff, ivlen);
if (!iv)
panic("assumption failed: bad mbuf chain");
bcopy((caddr_t)sav->iv, (caddr_t)iv, ivlen);
/* encrypt packet */
des_3cbc_process(m, bodyoff, plen, (des_key_schedule *)sav->sched,
(C_Block *)iv, DES_ENCRYPT);
esp_increment_iv(sav);
return 0;
}
static int
esp_3descbc_schedule(algo, sav)
const struct esp_algorithm *algo;
struct secasvar *sav;
{
int error;
des_key_schedule *p;
int i;
char *k;
p = (des_key_schedule *)sav->sched;
k = _KEYBUF(sav->key_enc);
for (i = 0; i < 3; i++) {
error = des_key_sched((C_Block *)(k + 8 * i), p[i]);
if (error)
return EINVAL;
}
return 0;
}
#ifdef SADB_X_EALG_RC5CBC
static int
esp_rc5cbc_ivlen(sav)
struct secasvar *sav;
{
return 8;
}
static int
esp_rc5cbc_decrypt(m, off, sav, algo, ivlen)
struct mbuf *m;
size_t off;
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t iv[8];
size_t plen;
int error;
/* sanity check */
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_rc5cbc_decrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR, "esp_rc5cbc_decrypt: unsupported ivlen %d\n",
ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
/* copy mbuf's IV into iv */
m_copydata(m, ivoff, 8, iv);
plen = m->m_pkthdr.len;
if (plen < bodyoff) {
panic("esp_rc5cbc_decrypt: too short packet: len=%lu",
(u_long)plen);
}
plen -= bodyoff;
if (plen % 8) {
ipseclog((LOG_ERR, "esp_rc5cbc_decrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
/* decrypt */
error = rc5_cbc_process(m, bodyoff, plen, (RC5_WORD *)sav->sched, iv,
RC5_DECRYPT);
return error;
}
static int
esp_rc5cbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off;
size_t plen;
struct secasvar *sav;
const struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
int error;
/* sanity check */
if (plen % 8) {
ipseclog((LOG_ERR, "esp_rc5cbc_encrypt: "
"payload length must be multiple of 8\n"));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
ipseclog((LOG_ERR,
"esp_rc5cbc_encrypt: unsupported ESP version\n"));
return EINVAL;
}
if (ivlen != 8) {
ipseclog((LOG_ERR, "esp_rc5cbc_encrypt: unsupported ivlen %d\n",
ivlen));
return EINVAL;
}
error = esp_crypto_sanity(algo, sav, ivlen);
if (error)
return error;
ivoff = off + sizeof(struct newesp);
bodyoff = off + sizeof(struct newesp) + ivlen;
if (m->m_pkthdr.len < bodyoff)
panic("assumption failed: mbuf too short");
iv = mbuf_find_offset(m, ivoff, ivlen);
if (!iv)
panic("assumption failed: bad mbuf chain");
bcopy(sav->iv, iv, ivlen);
/* encrypt */
error = rc5_cbc_process(m, bodyoff, plen, (RC5_WORD *)sav->sched, iv,
RC5_ENCRYPT);
esp_increment_iv(sav);
return error;
}
static int
esp_rc5cbc_schedule(algo, sav)
const struct esp_algorithm *algo;
struct secasvar *sav;
{
set_rc5_expandkey((RC5_WORD *)sav->sched, _KEYBUF(sav->key_enc),
_KEYLEN(sav->key_enc), 16);
return 0;
}
#endif
/*
* increment iv.
*/
static void
esp_increment_iv(sav)
struct secasvar *sav;
{
u_int8_t *x;
u_int8_t y;
int i;
y = time.tv_sec & 0xff;
if (!y) y++;
x = (u_int8_t *)sav->iv;
for (i = 0; i < sav->ivlen; i++) {
*x = (*x + y) & 0xff;
x++;
}
}
static caddr_t
mbuf_find_offset(m, off, len)
struct mbuf *m;
size_t off;
size_t len;
{
struct mbuf *n;
size_t cnt;
if (m->m_pkthdr.len < off || m->m_pkthdr.len < off + len)
return (caddr_t)NULL;
cnt = 0;
for (n = m; n; n = n->m_next) {
if (cnt + n->m_len <= off) {
cnt += n->m_len;
continue;
}
if (cnt <= off && off < cnt + n->m_len &&
cnt <= off + len && off + len <= cnt + n->m_len) {
return mtod(n, caddr_t) + off - cnt;
} else
return (caddr_t)NULL;
}
return (caddr_t)NULL;
}
/*------------------------------------------------------------*/
/* does not free m0 on error */
int
esp_auth(m0, skip, length, sav, sum)
struct mbuf *m0;
size_t skip; /* offset to ESP header */
size_t length; /* payload length */
struct secasvar *sav;
u_char *sum;
{
struct mbuf *m;
size_t off;
struct ah_algorithm_state s;
u_char sumbuf[AH_MAXSUMSIZE];
const struct ah_algorithm *algo;
size_t siz;
int error;
/* sanity checks */
if (m0->m_pkthdr.len < skip) {
ipseclog((LOG_DEBUG, "esp_auth: mbuf length < skip\n"));
return EINVAL;
}
if (m0->m_pkthdr.len < skip + length) {
ipseclog((LOG_DEBUG,
"esp_auth: mbuf length < skip + length\n"));
return EINVAL;
}
/*
* length of esp part (excluding authentication data) must be 4n,
* since nexthdr must be at offset 4n+3.
*/
if (length % 4) {
ipseclog((LOG_ERR, "esp_auth: length is not multiple of 4\n"));
return EINVAL;
}
if (!sav) {
ipseclog((LOG_DEBUG, "esp_auth: NULL SA passed\n"));
return EINVAL;
}
algo = ah_algorithm_lookup(sav->alg_auth);
if (!algo) {
ipseclog((LOG_ERR,
"esp_auth: bad ESP auth algorithm passed: %d\n",
sav->alg_auth));
return EINVAL;
}
m = m0;
off = 0;
siz = (((*algo->sumsiz)(sav) + 3) & ~(4 - 1));
if (sizeof(sumbuf) < siz) {
ipseclog((LOG_DEBUG,
"esp_auth: AH_MAXSUMSIZE is too small: siz=%lu\n",
(u_long)siz));
return EINVAL;
}
/* skip the header */
while (skip) {
if (!m)
panic("mbuf chain?");
if (m->m_len <= skip) {
skip -= m->m_len;
m = m->m_next;
off = 0;
} else {
off = skip;
skip = 0;
}
}
error = (*algo->init)(&s, sav);
if (error)
return error;
while (0 < length) {
if (!m)
panic("mbuf chain?");
if (m->m_len - off < length) {
(*algo->update)(&s, mtod(m, u_char *) + off,
m->m_len - off);
length -= m->m_len - off;
m = m->m_next;
off = 0;
} else {
(*algo->update)(&s, mtod(m, u_char *) + off, length);
break;
}
}
(*algo->result)(&s, sumbuf);
bcopy(sumbuf, sum, siz); /*XXX*/
return 0;
}