freebsd-dev/sys/netinet6/esp_core.c
2000-04-29 15:36:14 +00:00

1235 lines
29 KiB
C

/*
* 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.
*
* $FreeBSD$
*/
#include "opt_inet6.h"
#include "opt_ipsec.h"
#include <sys/param.h>
#include <sys/systm.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 <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#ifdef INET6
#include <netinet6/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/icmp6.h>
#endif
#include <netinet6/ipsec.h>
#include <netinet6/ah.h>
#ifdef INET6
#include <netinet6/ipsec6.h>
#include <netinet6/ah6.h>
#endif
#ifdef IPSEC_ESP
#include <netinet6/esp.h>
#ifdef INET6
#include <netinet6/esp6.h>
#endif
#endif
#include <net/pfkeyv2.h>
#include <netkey/key_var.h>
#include <netkey/keydb.h>
#include <crypto/des/des.h>
#include <crypto/blowfish/blowfish.h>
#include <crypto/cast128/cast128.h>
#include <crypto/rc5/rc5.h>
#include <net/net_osdep.h>
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 *, struct esp_algorithm *, int));
static int esp_null_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, 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 *, struct esp_algorithm *, int));
static int esp_descbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, struct esp_algorithm *, int));
static int esp_cbc_mature __P((struct secasvar *));
static int esp_blowfish_cbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, struct esp_algorithm *, int));
static int esp_blowfish_cbc_encrypt __P((struct mbuf *, size_t,
size_t, struct secasvar *, struct esp_algorithm *, int));
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 *, struct esp_algorithm *, int));
static int esp_cast128cbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, struct esp_algorithm *, int));
static int esp_3descbc_ivlen __P((struct secasvar *));
static int esp_3descbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, struct esp_algorithm *, int));
static int esp_3descbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, struct esp_algorithm *, int));
static int esp_rc5cbc_ivlen __P((struct secasvar *));
static int esp_rc5cbc_decrypt __P((struct mbuf *, size_t,
struct secasvar *, struct esp_algorithm *, int));
static int esp_rc5cbc_encrypt __P((struct mbuf *, size_t, size_t,
struct secasvar *, struct esp_algorithm *, int));
static void esp_increment_iv __P((struct secasvar *));
static caddr_t mbuf_find_offset __P((struct mbuf *, size_t, size_t));
/* NOTE: The order depends on SADB_EALG_x in netkey/keyv2.h */
struct esp_algorithm esp_algorithms[] = {
{ 0, 0, 0, 0, 0, 0, 0, },
{ 8, esp_descbc_mature, 64, 64,
esp_descbc_ivlen, esp_descbc_decrypt, esp_descbc_encrypt, },
{ 8, esp_cbc_mature, 192, 192,
esp_3descbc_ivlen, esp_3descbc_decrypt, esp_3descbc_encrypt, },
{ 1, esp_null_mature, 0, 2048,
esp_null_ivlen, esp_null_decrypt, esp_null_encrypt, },
{ 8, esp_cbc_mature, 40, 448,
esp_blowfish_cbc_ivlen, esp_blowfish_cbc_decrypt,
esp_blowfish_cbc_encrypt, },
{ 8, esp_cbc_mature, 40, 128,
esp_cast128cbc_ivlen, esp_cast128cbc_decrypt,
esp_cast128cbc_encrypt, },
{ 8, esp_cbc_mature, 40, 2040,
esp_rc5cbc_ivlen, esp_rc5cbc_decrypt, esp_rc5cbc_encrypt, },
};
/*
* 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;
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;
struct esp_algorithm *algo;
int ivlen;
{
return 0; /* do nothing */
}
static int
esp_descbc_mature(sav)
struct secasvar *sav;
{
struct esp_algorithm *algo;
if (!(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B)) {
printf("esp_cbc_mature: algorithm incompatible with 4 octets IV length\n");
return 1;
}
if (!sav->key_enc) {
printf("esp_descbc_mature: no key is given.\n");
return 1;
}
algo = &esp_algorithms[sav->alg_enc];
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("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))) {
printf("esp_descbc_mature: weak key was passed.\n");
return 1;
}
return 0;
}
static int
esp_descbc_ivlen(sav)
struct secasvar *sav;
{
if (sav && (sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_IV4B))
return 4;
if (sav && !(sav->flags & SADB_X_EXT_OLD) && (sav->flags & SADB_X_EXT_DERIV))
return 4;
else
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;
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;
derived = 0;
/* sanity check */
if (ivlen != sav->ivlen) {
printf("esp_descbc_decrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("esp_descbc_decrypt: bad keylen %d\n",
_KEYBITS(sav->key_enc));
return EINVAL;
}
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 {
printf("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) {
printf("esp_descbc_decrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
{
int deserr;
des_key_schedule ks;
deserr = des_key_sched((C_Block *)_KEYBUF(sav->key_enc), ks);
if (deserr != 0) {
printf("esp_descbc_decrypt: key error %d\n", deserr);
return EINVAL;
}
des_cbc_encrypt(m, bodyoff, plen, ks, (C_Block *)iv, DES_DECRYPT);
/* for safety */
bzero(&ks, sizeof(des_key_schedule));
}
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return 0;
}
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;
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;
derived = 0;
/* sanity check */
if (plen % 8) {
printf("esp_descbc_encrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
if (sav->ivlen != ivlen) {
printf("esp_descbc_encrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("esp_descbc_encrypt: bad keylen %d\n",
_KEYBITS(sav->key_enc));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
/* RFC 1827 */
/*
* draft-ietf-ipsec-ciph-des-derived-00.txt
* uses sequence number field as IV field.
* This draft has been deleted, see above.
*/
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, see above.
*/
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 {
printf("esp_descbc_encrypt: unsupported ivlen %d\n", ivlen);
return EINVAL;
}
{
int deserr;
des_key_schedule ks;
deserr = des_key_sched((C_Block *)_KEYBUF(sav->key_enc), ks);
if (deserr != 0) {
printf("esp_descbc_encrypt: key error %d\n", deserr);
return EINVAL;
}
des_cbc_encrypt(m, bodyoff, plen, ks, (C_Block *)iv, DES_ENCRYPT);
/* for safety */
bzero(&ks, sizeof(des_key_schedule));
}
esp_increment_iv(sav);
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return 0;
}
static int
esp_cbc_mature(sav)
struct secasvar *sav;
{
int keylen;
struct esp_algorithm *algo;
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_cbc_mature: algorithm incompatible with esp-old\n");
return 1;
}
if (sav->flags & SADB_X_EXT_DERIV) {
printf("esp_cbc_mature: algorithm incompatible with derived\n");
return 1;
}
if (!sav->key_enc) {
printf("esp_cbc_mature: no key is given.\n");
return 1;
}
algo = &esp_algorithms[sav->alg_enc];
keylen = sav->key_enc->sadb_key_bits;
if (keylen < algo->keymin || algo->keymax < keylen) {
printf("esp_cbc_mature: invalid key length %d.\n",
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))) {
printf("esp_cbc_mature: weak key was passed.\n");
return 1;
}
break;
case SADB_EALG_BLOWFISHCBC:
case SADB_EALG_CAST128CBC:
case SADB_EALG_RC5CBC:
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;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
u_int8_t tiv[8];
size_t plen;
static BF_KEY key; /* made static to avoid kernel stack overflow */
int s;
/* sanity check */
if (sav->ivlen != ivlen) {
printf("esp_blowfish_cbc_decrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("esp_blowfish_cbc_decrypt: unsupported key length %d: "
"need %d to %d bits\n", _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax);
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_blowfish_cbc_decrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_blowfish_cbc_decrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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) {
printf("esp_blowfish_cbc_decrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
s = splnet(); /* XXX correct? */
BF_set_key(&key, _KEYBITS(sav->key_enc) / 8, _KEYBUF(sav->key_enc));
BF_cbc_encrypt_m(m, bodyoff, plen, &key, iv, BF_DECRYPT);
/* for safety */
bzero(&key, sizeof(BF_KEY));
splx(s);
/* for safety */
bzero(&tiv[0], sizeof(tiv));
return 0;
}
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;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
static BF_KEY key; /* made static to avoid kernel stack overflow */
int s;
/* sanity check */
if (plen % 8) {
printf("esp_blowfish_cbc_encrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
if (sav->ivlen != ivlen) {
printf("esp_blowfish_cbc_encrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("esp_blowfish_cbc_encrypt: unsupported key length %d: "
"need %d to %d bits\n", _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax);
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_blowfish_cbc_encrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_blowfish_cbc_encrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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);
s = splnet(); /* XXX correct? */
BF_set_key(&key, _KEYBITS(sav->key_enc) / 8, _KEYBUF(sav->key_enc));
BF_cbc_encrypt_m(m, bodyoff, plen, &key, iv, BF_ENCRYPT);
/* for safety */
bzero(&key, sizeof(BF_KEY));
splx(s);
esp_increment_iv(sav);
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;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t iv[8];
size_t plen;
/* sanity check */
if (ivlen != sav->ivlen) {
printf("esp_cast128cbc_decrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| _KEYBITS(sav->key_enc) > algo->keymax) {
printf("esp_cast128cbc_decrypt: unsupported key length %d: "
"need %d to %d bits\n", _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax);
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_cast128cbc_decrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_cast128cbc_decrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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) {
printf("esp_cast128cbc_decrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
/* decrypt */
{
u_int8_t key[16];
u_int32_t subkey[32];
bzero(key, sizeof(key));
bcopy(_KEYBUF(sav->key_enc), key, _KEYLEN(sav->key_enc));
set_cast128_subkey(subkey, key);
cast128_cbc_process(m, bodyoff, plen, subkey, iv,
_KEYBITS(sav->key_enc) / 8, CAST128_DECRYPT);
/* for safety */
bzero(subkey, sizeof(subkey));
bzero(key, sizeof(key));
}
return 0;
}
static int
esp_cast128cbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off;
size_t plen;
struct secasvar *sav;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
/* sanity check */
if (plen % 8) {
printf("esp_cast128cbc_encrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
if (sav->ivlen != ivlen) {
printf("esp_cast128cbc_encrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| _KEYBITS(sav->key_enc) > algo->keymax) {
printf("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) {
printf("esp_cast128cbc_encrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_cast128cbc_encrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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 */
{
u_int8_t key[16];
u_int32_t subkey[32];
bzero(key, sizeof(key));
bcopy(_KEYBUF(sav->key_enc), key, _KEYLEN(sav->key_enc));
set_cast128_subkey(subkey, key);
cast128_cbc_process(m, bodyoff, plen, subkey, iv,
_KEYBITS(sav->key_enc) / 8, CAST128_ENCRYPT);
/* for safety */
bzero(subkey, sizeof(subkey));
bzero(key, sizeof(key));
}
esp_increment_iv(sav);
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;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
size_t plen;
u_int8_t tiv[8];
/* sanity check */
if (ivlen != sav->ivlen) {
printf("esp_3descbc_decrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("esp_3descbc_decrypt: bad keylen %d\n",
_KEYBITS(sav->key_enc));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_3descbc_decrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_3descbc_decrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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) {
printf("esp_3descbc_decrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
/* decrypt packet */
{
int deserr[3];
des_key_schedule ks[3];
deserr[0] = des_key_sched((C_Block *)_KEYBUF(sav->key_enc),ks[0]);
deserr[1] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 8), ks[1]);
deserr[2] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 16), ks[2]);
if ((deserr[0] != 0) || (deserr[1] != 0) || (deserr[2] != 0)) {
printf("esp_3descbc_decrypt: key error %d/%d/%d\n",
deserr[0], deserr[1], deserr[2]);
return EINVAL;
}
des_3cbc_process(m, bodyoff, plen, ks, (C_Block *)iv, DES_DECRYPT);
/* for safety */
bzero(ks[0], sizeof(des_key_schedule)*3);
}
/* 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;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
/* sanity check */
if (plen % 8) {
printf("esp_3descbc_encrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
if (sav->ivlen != ivlen) {
printf("esp_3descbc_encrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| algo->keymax < _KEYBITS(sav->key_enc)) {
printf("esp_3descbc_encrypt: bad keylen %d\n",
_KEYBITS(sav->key_enc));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_3descbc_encrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_3descbc_encrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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 */
{
int deserr[3];
des_key_schedule ks[3];
deserr[0] = des_key_sched((C_Block *)_KEYBUF(sav->key_enc), ks[0]);
deserr[1] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 8), ks[1]);
deserr[2] = des_key_sched((C_Block *)(_KEYBUF(sav->key_enc) + 16), ks[2]);
if ((deserr[0] != 0) || (deserr[1] != 0) || (deserr[2] != 0)) {
printf("esp_3descbc_encrypt: key error %d/%d/%d\n",
deserr[0], deserr[1], deserr[2]);
return EINVAL;
}
des_3cbc_process(m, bodyoff, plen, ks, (C_Block *)iv, DES_ENCRYPT);
/* for safety */
bzero(ks[0], sizeof(des_key_schedule)*3);
}
esp_increment_iv(sav);
return 0;
}
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;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t iv[8];
size_t plen;
/* sanity check */
if (sav->ivlen != ivlen) {
printf("esp_rc5cbc_decrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if ((_KEYBITS(sav->key_enc) < 40) || (_KEYBITS(sav->key_enc) > 2040)) {
printf("esp_rc5cbc_decrypt: unsupported key length %d: "
"need 40 to 2040 bit\n", _KEYBITS(sav->key_enc));
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_rc5cbc_decrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_rc5cbc_decrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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) {
printf("esp_rc5cbc_decrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
/* decrypt */
{
RC5_WORD e_key[34];
set_rc5_expandkey(e_key, _KEYBUF(sav->key_enc),
_KEYBITS(sav->key_enc) / 8, 16);
rc5_cbc_process(m, bodyoff, plen, e_key, iv, RC5_DECRYPT);
/* for safety */
bzero(e_key, sizeof(e_key));
}
return 0;
}
static int
esp_rc5cbc_encrypt(m, off, plen, sav, algo, ivlen)
struct mbuf *m;
size_t off;
size_t plen;
struct secasvar *sav;
struct esp_algorithm *algo;
int ivlen;
{
size_t ivoff;
size_t bodyoff;
u_int8_t *iv;
/* sanity check */
if (plen % 8) {
printf("esp_rc5cbc_encrypt: "
"payload length must be multiple of 8\n");
return EINVAL;
}
if (sav->ivlen != ivlen) {
printf("esp_rc5cbc_encrypt: bad ivlen %d/%d\n",
ivlen, sav->ivlen);
return EINVAL;
}
if (_KEYBITS(sav->key_enc) < algo->keymin
|| _KEYBITS(sav->key_enc) > algo->keymax) {
printf("esp_rc5cbc_encrypt: unsupported key length %d: "
"need %d to %d bits\n", _KEYBITS(sav->key_enc),
algo->keymin, algo->keymax);
return EINVAL;
}
if (sav->flags & SADB_X_EXT_OLD) {
printf("esp_rc5cbc_encrypt: unsupported ESP version\n");
return EINVAL;
}
if (ivlen != 8) {
printf("esp_rc5cbc_encrypt: unsupported ivlen %d "
"(this should never happen)\n", ivlen);
return EINVAL;
}
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 */
{
RC5_WORD e_key[34];
set_rc5_expandkey(e_key, _KEYBUF(sav->key_enc),
_KEYBITS(sav->key_enc) / 8, 16);
rc5_cbc_process(m, bodyoff, plen, e_key, iv, RC5_ENCRYPT);
/* for safety */
bzero(e_key, sizeof(e_key));
}
esp_increment_iv(sav);
return 0;
}
/*
* increment iv.
*/
static void
esp_increment_iv(sav)
struct secasvar *sav;
{
u_int8_t *x;
u_int8_t y;
int i;
y = time_second & 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;
}
/*------------------------------------------------------------*/
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];
struct ah_algorithm *algo;
size_t siz;
/* sanity checks */
if (m0->m_pkthdr.len < skip) {
printf("esp_auth: mbuf length < skip\n");
return EINVAL;
}
if (m0->m_pkthdr.len < skip + length) {
printf("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) {
printf("esp_auth: length is not multiple of 4\n");
return EINVAL;
}
if (!sav) {
printf("esp_auth: NULL SA passed\n");
return EINVAL;
}
if (!sav->alg_auth) {
printf("esp_auth: bad ESP auth algorithm passed: %d\n", sav->alg_auth);
return EINVAL;
}
m = m0;
off = 0;
algo = &ah_algorithms[sav->alg_auth];
siz = (((*algo->sumsiz)(sav) + 3) & ~(4 - 1));
if (sizeof(sumbuf) < siz) {
printf("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;
}
}
(*algo->init)(&s, sav);
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;
}