295 lines
9.8 KiB
C
295 lines
9.8 KiB
C
|
/**********************************************************************
|
||
|
* gost_keyx.c *
|
||
|
* Copyright (c) 2005-2006 Cryptocom LTD *
|
||
|
* This file is distributed under the same license as OpenSSL *
|
||
|
* *
|
||
|
* VK0 34.10-2001 key exchange and GOST R 34.10-2001 *
|
||
|
* based PKCS7/SMIME support *
|
||
|
* Requires OpenSSL 0.9.9 for compilation *
|
||
|
**********************************************************************/
|
||
|
#include <openssl/evp.h>
|
||
|
#include <openssl/rand.h>
|
||
|
#include <string.h>
|
||
|
#include <openssl/objects.h>
|
||
|
#include "gost89.h"
|
||
|
#include "gosthash.h"
|
||
|
#include "e_gost_err.h"
|
||
|
#include "gost_keywrap.h"
|
||
|
#include "gost_lcl.h"
|
||
|
#include "gost2001_keyx.h"
|
||
|
|
||
|
/* Implementation of CryptoPro VKO 34.10-2001 algorithm */
|
||
|
static int VKO_compute_key(unsigned char *shared_key, size_t shared_key_size,
|
||
|
const EC_POINT *pub_key, EC_KEY *priv_key,
|
||
|
const unsigned char *ukm)
|
||
|
{
|
||
|
unsigned char ukm_be[8], databuf[64], hashbuf[64];
|
||
|
BIGNUM *UKM = NULL, *p = NULL, *order = NULL, *X = NULL, *Y = NULL;
|
||
|
const BIGNUM *key = EC_KEY_get0_private_key(priv_key);
|
||
|
EC_POINT *pnt = EC_POINT_new(EC_KEY_get0_group(priv_key));
|
||
|
int i;
|
||
|
gost_hash_ctx hash_ctx;
|
||
|
BN_CTX *ctx = BN_CTX_new();
|
||
|
|
||
|
for (i = 0; i < 8; i++) {
|
||
|
ukm_be[7 - i] = ukm[i];
|
||
|
}
|
||
|
BN_CTX_start(ctx);
|
||
|
UKM = getbnfrombuf(ukm_be, 8);
|
||
|
p = BN_CTX_get(ctx);
|
||
|
order = BN_CTX_get(ctx);
|
||
|
X = BN_CTX_get(ctx);
|
||
|
Y = BN_CTX_get(ctx);
|
||
|
EC_GROUP_get_order(EC_KEY_get0_group(priv_key), order, ctx);
|
||
|
BN_mod_mul(p, key, UKM, order, ctx);
|
||
|
EC_POINT_mul(EC_KEY_get0_group(priv_key), pnt, NULL, pub_key, p, ctx);
|
||
|
EC_POINT_get_affine_coordinates_GFp(EC_KEY_get0_group(priv_key),
|
||
|
pnt, X, Y, ctx);
|
||
|
/*
|
||
|
* Serialize elliptic curve point same way as we do it when saving key
|
||
|
*/
|
||
|
store_bignum(Y, databuf, 32);
|
||
|
store_bignum(X, databuf + 32, 32);
|
||
|
/* And reverse byte order of whole buffer */
|
||
|
for (i = 0; i < 64; i++) {
|
||
|
hashbuf[63 - i] = databuf[i];
|
||
|
}
|
||
|
init_gost_hash_ctx(&hash_ctx, &GostR3411_94_CryptoProParamSet);
|
||
|
start_hash(&hash_ctx);
|
||
|
hash_block(&hash_ctx, hashbuf, 64);
|
||
|
finish_hash(&hash_ctx, shared_key);
|
||
|
done_gost_hash_ctx(&hash_ctx);
|
||
|
BN_free(UKM);
|
||
|
BN_CTX_end(ctx);
|
||
|
BN_CTX_free(ctx);
|
||
|
EC_POINT_free(pnt);
|
||
|
return 32;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* EVP_PKEY_METHOD callback derive. Implements VKO R 34.10-2001
|
||
|
* algorithm
|
||
|
*/
|
||
|
int pkey_gost2001_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
|
||
|
size_t *keylen)
|
||
|
{
|
||
|
/*
|
||
|
* Public key of peer in the ctx field peerkey Our private key in the ctx
|
||
|
* pkey ukm is in the algorithm specific context data
|
||
|
*/
|
||
|
EVP_PKEY *my_key = EVP_PKEY_CTX_get0_pkey(ctx);
|
||
|
EVP_PKEY *peer_key = EVP_PKEY_CTX_get0_peerkey(ctx);
|
||
|
struct gost_pmeth_data *data = EVP_PKEY_CTX_get_data(ctx);
|
||
|
|
||
|
if (!data->shared_ukm) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST2001_DERIVE, GOST_R_UKM_NOT_SET);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
if (key == NULL) {
|
||
|
*keylen = 32;
|
||
|
return 32;
|
||
|
}
|
||
|
|
||
|
*keylen =
|
||
|
VKO_compute_key(key, 32,
|
||
|
EC_KEY_get0_public_key(EVP_PKEY_get0(peer_key)),
|
||
|
(EC_KEY *)EVP_PKEY_get0(my_key), data->shared_ukm);
|
||
|
return 1;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* EVP_PKEY_METHOD callback encrypt
|
||
|
* Implementation of GOST2001 key transport, cryptocom variation
|
||
|
*/
|
||
|
/*
|
||
|
* Generates ephemeral key based on pubk algorithm computes shared key using
|
||
|
* VKO and returns filled up GOST_KEY_TRANSPORT structure
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
* EVP_PKEY_METHOD callback encrypt
|
||
|
* Implementation of GOST2001 key transport, cryptopo variation
|
||
|
*/
|
||
|
|
||
|
int pkey_GOST01cp_encrypt(EVP_PKEY_CTX *pctx, unsigned char *out,
|
||
|
size_t *out_len, const unsigned char *key,
|
||
|
size_t key_len)
|
||
|
{
|
||
|
GOST_KEY_TRANSPORT *gkt = NULL;
|
||
|
EVP_PKEY *pubk = EVP_PKEY_CTX_get0_pkey(pctx);
|
||
|
struct gost_pmeth_data *data = EVP_PKEY_CTX_get_data(pctx);
|
||
|
const struct gost_cipher_info *param = get_encryption_params(NULL);
|
||
|
unsigned char ukm[8], shared_key[32], crypted_key[44];
|
||
|
int ret = 0;
|
||
|
int key_is_ephemeral = 1;
|
||
|
gost_ctx cctx;
|
||
|
EVP_PKEY *sec_key = EVP_PKEY_CTX_get0_peerkey(pctx);
|
||
|
if (data->shared_ukm) {
|
||
|
memcpy(ukm, data->shared_ukm, 8);
|
||
|
} else if (out) {
|
||
|
|
||
|
if (RAND_bytes(ukm, 8) <= 0) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_ENCRYPT,
|
||
|
GOST_R_RANDOM_GENERATOR_FAILURE);
|
||
|
return 0;
|
||
|
}
|
||
|
}
|
||
|
/* Check for private key in the peer_key of context */
|
||
|
if (sec_key) {
|
||
|
key_is_ephemeral = 0;
|
||
|
if (!gost_get0_priv_key(sec_key)) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_ENCRYPT,
|
||
|
GOST_R_NO_PRIVATE_PART_OF_NON_EPHEMERAL_KEYPAIR);
|
||
|
goto err;
|
||
|
}
|
||
|
} else {
|
||
|
key_is_ephemeral = 1;
|
||
|
if (out) {
|
||
|
sec_key = EVP_PKEY_new();
|
||
|
if (sec_key == NULL)
|
||
|
goto err;
|
||
|
EVP_PKEY_assign(sec_key, EVP_PKEY_base_id(pubk), EC_KEY_new());
|
||
|
EVP_PKEY_copy_parameters(sec_key, pubk);
|
||
|
if (!gost2001_keygen(EVP_PKEY_get0(sec_key))) {
|
||
|
goto err;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if (!get_gost_engine_param(GOST_PARAM_CRYPT_PARAMS)
|
||
|
&& param == gost_cipher_list) {
|
||
|
param = gost_cipher_list + 1;
|
||
|
}
|
||
|
if (out) {
|
||
|
VKO_compute_key(shared_key, 32,
|
||
|
EC_KEY_get0_public_key(EVP_PKEY_get0(pubk)),
|
||
|
EVP_PKEY_get0(sec_key), ukm);
|
||
|
gost_init(&cctx, param->sblock);
|
||
|
keyWrapCryptoPro(&cctx, shared_key, ukm, key, crypted_key);
|
||
|
}
|
||
|
gkt = GOST_KEY_TRANSPORT_new();
|
||
|
if (!gkt) {
|
||
|
goto err;
|
||
|
}
|
||
|
if (!ASN1_OCTET_STRING_set(gkt->key_agreement_info->eph_iv, ukm, 8)) {
|
||
|
goto err;
|
||
|
}
|
||
|
if (!ASN1_OCTET_STRING_set(gkt->key_info->imit, crypted_key + 40, 4)) {
|
||
|
goto err;
|
||
|
}
|
||
|
if (!ASN1_OCTET_STRING_set
|
||
|
(gkt->key_info->encrypted_key, crypted_key + 8, 32)) {
|
||
|
goto err;
|
||
|
}
|
||
|
if (key_is_ephemeral) {
|
||
|
if (!X509_PUBKEY_set
|
||
|
(&gkt->key_agreement_info->ephem_key, out ? sec_key : pubk)) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_ENCRYPT,
|
||
|
GOST_R_CANNOT_PACK_EPHEMERAL_KEY);
|
||
|
goto err;
|
||
|
}
|
||
|
}
|
||
|
ASN1_OBJECT_free(gkt->key_agreement_info->cipher);
|
||
|
gkt->key_agreement_info->cipher = OBJ_nid2obj(param->nid);
|
||
|
if (key_is_ephemeral && sec_key)
|
||
|
EVP_PKEY_free(sec_key);
|
||
|
if (!key_is_ephemeral) {
|
||
|
/* Set control "public key from client certificate used" */
|
||
|
if (EVP_PKEY_CTX_ctrl(pctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 3, NULL)
|
||
|
<= 0) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_ENCRYPT, GOST_R_CTRL_CALL_FAILED);
|
||
|
goto err;
|
||
|
}
|
||
|
}
|
||
|
if ((*out_len = i2d_GOST_KEY_TRANSPORT(gkt, out ? &out : NULL)) > 0)
|
||
|
ret = 1;
|
||
|
GOST_KEY_TRANSPORT_free(gkt);
|
||
|
return ret;
|
||
|
err:
|
||
|
if (key_is_ephemeral && sec_key)
|
||
|
EVP_PKEY_free(sec_key);
|
||
|
GOST_KEY_TRANSPORT_free(gkt);
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* EVP_PKEY_METHOD callback decrypt
|
||
|
* Implementation of GOST2001 key transport, cryptopo variation
|
||
|
*/
|
||
|
int pkey_GOST01cp_decrypt(EVP_PKEY_CTX *pctx, unsigned char *key,
|
||
|
size_t *key_len, const unsigned char *in,
|
||
|
size_t in_len)
|
||
|
{
|
||
|
const unsigned char *p = in;
|
||
|
EVP_PKEY *priv = EVP_PKEY_CTX_get0_pkey(pctx);
|
||
|
GOST_KEY_TRANSPORT *gkt = NULL;
|
||
|
int ret = 0;
|
||
|
unsigned char wrappedKey[44];
|
||
|
unsigned char sharedKey[32];
|
||
|
gost_ctx ctx;
|
||
|
const struct gost_cipher_info *param = NULL;
|
||
|
EVP_PKEY *eph_key = NULL, *peerkey = NULL;
|
||
|
|
||
|
if (!key) {
|
||
|
*key_len = 32;
|
||
|
return 1;
|
||
|
}
|
||
|
gkt = d2i_GOST_KEY_TRANSPORT(NULL, (const unsigned char **)&p, in_len);
|
||
|
if (!gkt) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_DECRYPT,
|
||
|
GOST_R_ERROR_PARSING_KEY_TRANSPORT_INFO);
|
||
|
return -1;
|
||
|
}
|
||
|
|
||
|
/* If key transport structure contains public key, use it */
|
||
|
eph_key = X509_PUBKEY_get(gkt->key_agreement_info->ephem_key);
|
||
|
if (eph_key) {
|
||
|
if (EVP_PKEY_derive_set_peer(pctx, eph_key) <= 0) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_DECRYPT,
|
||
|
GOST_R_INCOMPATIBLE_PEER_KEY);
|
||
|
goto err;
|
||
|
}
|
||
|
} else {
|
||
|
/* Set control "public key from client certificate used" */
|
||
|
if (EVP_PKEY_CTX_ctrl(pctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 3, NULL)
|
||
|
<= 0) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_DECRYPT, GOST_R_CTRL_CALL_FAILED);
|
||
|
goto err;
|
||
|
}
|
||
|
}
|
||
|
peerkey = EVP_PKEY_CTX_get0_peerkey(pctx);
|
||
|
if (!peerkey) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_DECRYPT, GOST_R_NO_PEER_KEY);
|
||
|
goto err;
|
||
|
}
|
||
|
|
||
|
param = get_encryption_params(gkt->key_agreement_info->cipher);
|
||
|
if (!param) {
|
||
|
goto err;
|
||
|
}
|
||
|
|
||
|
gost_init(&ctx, param->sblock);
|
||
|
OPENSSL_assert(gkt->key_agreement_info->eph_iv->length == 8);
|
||
|
memcpy(wrappedKey, gkt->key_agreement_info->eph_iv->data, 8);
|
||
|
OPENSSL_assert(gkt->key_info->encrypted_key->length == 32);
|
||
|
memcpy(wrappedKey + 8, gkt->key_info->encrypted_key->data, 32);
|
||
|
OPENSSL_assert(gkt->key_info->imit->length == 4);
|
||
|
memcpy(wrappedKey + 40, gkt->key_info->imit->data, 4);
|
||
|
VKO_compute_key(sharedKey, 32,
|
||
|
EC_KEY_get0_public_key(EVP_PKEY_get0(peerkey)),
|
||
|
EVP_PKEY_get0(priv), wrappedKey);
|
||
|
if (!keyUnwrapCryptoPro(&ctx, sharedKey, wrappedKey, key)) {
|
||
|
GOSTerr(GOST_F_PKEY_GOST01CP_DECRYPT,
|
||
|
GOST_R_ERROR_COMPUTING_SHARED_KEY);
|
||
|
goto err;
|
||
|
}
|
||
|
|
||
|
ret = 1;
|
||
|
err:
|
||
|
if (eph_key)
|
||
|
EVP_PKEY_free(eph_key);
|
||
|
if (gkt)
|
||
|
GOST_KEY_TRANSPORT_free(gkt);
|
||
|
return ret;
|
||
|
}
|