This commit is contained in:
Martin Willi
@@ -0,0 +1,261 @@
|
||||
/* crypto interfaces
|
||||
* Copyright (C) 1998-2001 D. Hugh Redelmeier.
|
||||
*
|
||||
* This program is free software; you can redistribute it and/or modify it
|
||||
* under the terms of the GNU General Public License as published by the
|
||||
* Free Software Foundation; either version 2 of the License, or (at your
|
||||
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
|
||||
*
|
||||
* This program is distributed in the hope that it will be useful, but
|
||||
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||||
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
||||
* for more details.
|
||||
*
|
||||
* RCSID $Id: crypto.c,v 1.5 2005/12/06 22:51:34 as Exp $
|
||||
*/
|
||||
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
#include <stddef.h>
|
||||
#include <sys/types.h>
|
||||
|
||||
#include <freeswan.h>
|
||||
#define HEADER_DES_LOCL_H /* stupid trick to force prototype decl in <des.h> */
|
||||
#include <crypto/des.h>
|
||||
|
||||
#include <errno.h>
|
||||
|
||||
#include "constants.h"
|
||||
#include "defs.h"
|
||||
#include "state.h"
|
||||
#include "log.h"
|
||||
#include "md5.h"
|
||||
#include "sha1.h"
|
||||
#include "crypto.h" /* requires sha1.h and md5.h */
|
||||
#include "alg_info.h"
|
||||
#include "ike_alg.h"
|
||||
|
||||
|
||||
/* moduli and generator. */
|
||||
|
||||
static MP_INT
|
||||
modp1024_modulus,
|
||||
modp1536_modulus,
|
||||
modp2048_modulus,
|
||||
modp3072_modulus,
|
||||
modp4096_modulus,
|
||||
modp6144_modulus,
|
||||
modp8192_modulus;
|
||||
|
||||
MP_INT groupgenerator; /* MODP group generator (2) */
|
||||
|
||||
static void do_3des(u_int8_t *buf, size_t buf_len, u_int8_t *key, size_t key_size, u_int8_t *iv, bool enc);
|
||||
|
||||
static struct encrypt_desc crypto_encryptor_3des =
|
||||
{
|
||||
algo_type: IKE_ALG_ENCRYPT,
|
||||
algo_id: OAKLEY_3DES_CBC,
|
||||
algo_next: NULL,
|
||||
enc_ctxsize: sizeof(des_key_schedule) * 3,
|
||||
enc_blocksize: DES_CBC_BLOCK_SIZE,
|
||||
keydeflen: DES_CBC_BLOCK_SIZE * 3 * BITS_PER_BYTE,
|
||||
keyminlen: DES_CBC_BLOCK_SIZE * 3 * BITS_PER_BYTE,
|
||||
keymaxlen: DES_CBC_BLOCK_SIZE * 3 * BITS_PER_BYTE,
|
||||
do_crypt: do_3des,
|
||||
};
|
||||
|
||||
static struct hash_desc crypto_hasher_md5 =
|
||||
{
|
||||
algo_type: IKE_ALG_HASH,
|
||||
algo_id: OAKLEY_MD5,
|
||||
algo_next: NULL,
|
||||
hash_ctx_size: sizeof(MD5_CTX),
|
||||
hash_digest_size: MD5_DIGEST_SIZE,
|
||||
hash_init: (void (*)(void *)) MD5Init,
|
||||
hash_update: (void (*)(void *, const u_int8_t *, size_t)) MD5Update,
|
||||
hash_final: (void (*)(u_char *, void *)) MD5Final,
|
||||
};
|
||||
|
||||
static struct hash_desc crypto_hasher_sha1 =
|
||||
{
|
||||
algo_type: IKE_ALG_HASH,
|
||||
algo_id: OAKLEY_SHA,
|
||||
algo_next: NULL,
|
||||
hash_ctx_size: sizeof(SHA1_CTX),
|
||||
hash_digest_size: SHA1_DIGEST_SIZE,
|
||||
hash_init: (void (*)(void *)) SHA1Init,
|
||||
hash_update: (void (*)(void *, const u_int8_t *, size_t)) SHA1Update,
|
||||
hash_final: (void (*)(u_char *, void *)) SHA1Final,
|
||||
};
|
||||
|
||||
void
|
||||
init_crypto(void)
|
||||
{
|
||||
if (mpz_init_set_str(&groupgenerator, MODP_GENERATOR, 10) != 0
|
||||
|| mpz_init_set_str(&modp1024_modulus, MODP1024_MODULUS, 16) != 0
|
||||
|| mpz_init_set_str(&modp1536_modulus, MODP1536_MODULUS, 16) != 0
|
||||
|| mpz_init_set_str(&modp2048_modulus, MODP2048_MODULUS, 16) != 0
|
||||
|| mpz_init_set_str(&modp3072_modulus, MODP3072_MODULUS, 16) != 0
|
||||
|| mpz_init_set_str(&modp4096_modulus, MODP4096_MODULUS, 16) != 0
|
||||
|| mpz_init_set_str(&modp6144_modulus, MODP6144_MODULUS, 16) != 0
|
||||
|| mpz_init_set_str(&modp8192_modulus, MODP8192_MODULUS, 16) != 0)
|
||||
exit_log("mpz_init_set_str() failed in init_crypto()");
|
||||
|
||||
ike_alg_add((struct ike_alg *) &crypto_encryptor_3des);
|
||||
ike_alg_add((struct ike_alg *) &crypto_hasher_sha1);
|
||||
ike_alg_add((struct ike_alg *) &crypto_hasher_md5);
|
||||
ike_alg_init();
|
||||
}
|
||||
|
||||
/* Oakley group description
|
||||
*
|
||||
* See RFC2409 "The Internet key exchange (IKE)" 6.
|
||||
*/
|
||||
|
||||
const struct oakley_group_desc unset_group = {0, NULL, 0}; /* magic signifier */
|
||||
|
||||
const struct oakley_group_desc oakley_group[OAKLEY_GROUP_SIZE] = {
|
||||
# define BYTES(bits) (((bits) + BITS_PER_BYTE - 1) / BITS_PER_BYTE)
|
||||
{ OAKLEY_GROUP_MODP1024, &modp1024_modulus, BYTES(1024) },
|
||||
{ OAKLEY_GROUP_MODP1536, &modp1536_modulus, BYTES(1536) },
|
||||
{ OAKLEY_GROUP_MODP2048, &modp2048_modulus, BYTES(2048) },
|
||||
{ OAKLEY_GROUP_MODP3072, &modp3072_modulus, BYTES(3072) },
|
||||
{ OAKLEY_GROUP_MODP4096, &modp4096_modulus, BYTES(4096) },
|
||||
{ OAKLEY_GROUP_MODP6144, &modp6144_modulus, BYTES(6144) },
|
||||
{ OAKLEY_GROUP_MODP8192, &modp8192_modulus, BYTES(8192) },
|
||||
# undef BYTES
|
||||
};
|
||||
|
||||
const struct oakley_group_desc *
|
||||
lookup_group(u_int16_t group)
|
||||
{
|
||||
int i;
|
||||
|
||||
for (i = 0; i != elemsof(oakley_group); i++)
|
||||
if (group == oakley_group[i].group)
|
||||
return &oakley_group[i];
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Encryption Routines
|
||||
*
|
||||
* Each uses and updates the state object's st_new_iv.
|
||||
* This must already be initialized.
|
||||
*/
|
||||
|
||||
/* encrypt or decrypt part of an IKE message using DES
|
||||
* See RFC 2409 "IKE" Appendix B
|
||||
*/
|
||||
static void __attribute__ ((unused))
|
||||
do_des(bool enc, void *buf, size_t buf_len, struct state *st)
|
||||
{
|
||||
des_key_schedule ks;
|
||||
|
||||
(void) des_set_key((des_cblock *)st->st_enc_key.ptr, ks);
|
||||
|
||||
passert(st->st_new_iv_len >= DES_CBC_BLOCK_SIZE);
|
||||
st->st_new_iv_len = DES_CBC_BLOCK_SIZE; /* truncate */
|
||||
|
||||
des_ncbc_encrypt((des_cblock *)buf, (des_cblock *)buf, buf_len,
|
||||
ks,
|
||||
(des_cblock *)st->st_new_iv, enc);
|
||||
}
|
||||
|
||||
/* encrypt or decrypt part of an IKE message using 3DES
|
||||
* See RFC 2409 "IKE" Appendix B
|
||||
*/
|
||||
static void
|
||||
do_3des(u_int8_t *buf, size_t buf_len, u_int8_t *key, size_t key_size, u_int8_t *iv, bool enc)
|
||||
{
|
||||
des_key_schedule ks[3];
|
||||
|
||||
passert (!key_size || (key_size==(DES_CBC_BLOCK_SIZE * 3)))
|
||||
(void) des_set_key((des_cblock *)key + 0, ks[0]);
|
||||
(void) des_set_key((des_cblock *)key + 1, ks[1]);
|
||||
(void) des_set_key((des_cblock *)key + 2, ks[2]);
|
||||
|
||||
des_ede3_cbc_encrypt((des_cblock *)buf, (des_cblock *)buf, buf_len,
|
||||
ks[0], ks[1], ks[2],
|
||||
(des_cblock *)iv, enc);
|
||||
}
|
||||
|
||||
/* hash and prf routines */
|
||||
void
|
||||
crypto_cbc_encrypt(const struct encrypt_desc *e, bool enc, u_int8_t *buf, size_t size, struct state *st)
|
||||
{
|
||||
passert(st->st_new_iv_len >= e->enc_blocksize);
|
||||
st->st_new_iv_len = e->enc_blocksize; /* truncate */
|
||||
|
||||
e->do_crypt(buf, size, st->st_enc_key.ptr, st->st_enc_key.len, st->st_new_iv, enc);
|
||||
/*
|
||||
e->set_key(&ctx, st->st_enc_key.ptr, st->st_enc_key.len);
|
||||
e->cbc_crypt(&ctx, buf, size, st->st_new_iv, enc);
|
||||
*/
|
||||
}
|
||||
|
||||
/* HMAC package
|
||||
* rfc2104.txt specifies how HMAC works.
|
||||
*/
|
||||
|
||||
void
|
||||
hmac_init(struct hmac_ctx *ctx,
|
||||
const struct hash_desc *h,
|
||||
const u_char *key, size_t key_len)
|
||||
{
|
||||
int k;
|
||||
|
||||
ctx->h = h;
|
||||
ctx->hmac_digest_size = h->hash_digest_size;
|
||||
|
||||
/* Prepare the two pads for the HMAC */
|
||||
|
||||
memset(ctx->buf1, '\0', HMAC_BUFSIZE);
|
||||
|
||||
if (key_len <= HMAC_BUFSIZE)
|
||||
{
|
||||
memcpy(ctx->buf1, key, key_len);
|
||||
}
|
||||
else
|
||||
{
|
||||
h->hash_init(&ctx->hash_ctx);
|
||||
h->hash_update(&ctx->hash_ctx, key, key_len);
|
||||
h->hash_final(ctx->buf1, &ctx->hash_ctx);
|
||||
}
|
||||
|
||||
memcpy(ctx->buf2, ctx->buf1, HMAC_BUFSIZE);
|
||||
|
||||
for (k = 0; k < HMAC_BUFSIZE; k++)
|
||||
{
|
||||
ctx->buf1[k] ^= HMAC_IPAD;
|
||||
ctx->buf2[k] ^= HMAC_OPAD;
|
||||
}
|
||||
|
||||
hmac_reinit(ctx);
|
||||
}
|
||||
|
||||
void
|
||||
hmac_reinit(struct hmac_ctx *ctx)
|
||||
{
|
||||
ctx->h->hash_init(&ctx->hash_ctx);
|
||||
ctx->h->hash_update(&ctx->hash_ctx, ctx->buf1, HMAC_BUFSIZE);
|
||||
}
|
||||
|
||||
void
|
||||
hmac_update(struct hmac_ctx *ctx,
|
||||
const u_char *data, size_t data_len)
|
||||
{
|
||||
ctx->h->hash_update(&ctx->hash_ctx, data, data_len);
|
||||
}
|
||||
|
||||
void
|
||||
hmac_final(u_char *output, struct hmac_ctx *ctx)
|
||||
{
|
||||
const struct hash_desc *h = ctx->h;
|
||||
|
||||
h->hash_final(output, &ctx->hash_ctx);
|
||||
|
||||
h->hash_init(&ctx->hash_ctx);
|
||||
h->hash_update(&ctx->hash_ctx, ctx->buf2, HMAC_BUFSIZE);
|
||||
h->hash_update(&ctx->hash_ctx, output, h->hash_digest_size);
|
||||
h->hash_final(output, &ctx->hash_ctx);
|
||||
}
|
||||
Reference in New Issue
Block a user