engines/ccgost/gost94_keyx.c - third_party/openssl - Git at Google

 /**********************************************************************
  *                             gost94_keyx.c                          *
  *             Copyright (c) 2005-2006 Cryptocom LTD                  *
  *         This file is distributed under the same license as OpenSSL *
  *                                                                    *
  *     Implements generation and parsing of GOST_KEY_TRANSPORT for    *
  *     			GOST R 34.10-94 algorithms                            *
  *																	  *
  *          Requires OpenSSL 0.9.9 for compilation                    *
  **********************************************************************/
 #include <string.h>
 #include <openssl/dh.h>
 #include <openssl/rand.h>
 #include <openssl/evp.h>
 #include <openssl/objects.h>

 #include "gost89.h"
 #include "gosthash.h"
 #include "e_gost_err.h"
 #include "gost_keywrap.h"
 #include "gost_lcl.h"
 /* Common functions for both 94 and 2001 key exchange schemes */
 /* Implementation of the Diffi-Hellman key agreement scheme based on
  * GOST-94 keys */

 /* Computes Diffie-Hellman key and stores it into buffer in
  * little-endian byte order as expected by both versions of GOST 94
  * algorithm
  */
 static int compute_pair_key_le(unsigned char *pair_key,BIGNUM *pub_key,DH *dh)
 	{
 	unsigned char be_key[128];
 	int i,key_size;
 	key_size=DH_compute_key(be_key,pub_key,dh);
 	if (!key_size) return 0;
 	memset(pair_key,0,128);
 	for (i=0;i<key_size;i++)
 		{
 		pair_key[i]=be_key[key_size-1-i];
 		}
 	return key_size;
 	}

 /*
  * Computes 256 bit Key exchange key as specified in RFC 4357
  */
 static int make_cp_exchange_key(BIGNUM *priv_key,EVP_PKEY *pubk, unsigned char *shared_key)
 	{
 	unsigned char dh_key [128];
 	int ret;
 	gost_hash_ctx hash_ctx;
 	DH *dh = DH_new();

 	if (!dh)
 		return 0;
 	memset(dh_key,0,128);
 	dh->g = BN_dup(pubk->pkey.dsa->g);
 	dh->p = BN_dup(pubk->pkey.dsa->p);
 	dh->priv_key = BN_dup(priv_key);
 	ret=compute_pair_key_le(dh_key,((DSA *)(EVP_PKEY_get0(pubk)))->pub_key,dh) ;
 	DH_free(dh);
 	if (!ret)	return 0;
 	init_gost_hash_ctx(&hash_ctx,&GostR3411_94_CryptoProParamSet);
 	start_hash(&hash_ctx);
 	hash_block(&hash_ctx,dh_key,128);
 	finish_hash(&hash_ctx,shared_key);
 	done_gost_hash_ctx(&hash_ctx);
 	return 1;
 	}

 /* EVP_PKEY_METHOD callback derive. Implements VKO R 34.10-94 */

 int pkey_gost94_derive(EVP_PKEY_CTX *ctx,unsigned char *key,size_t *keylen)
 	{
 		EVP_PKEY *pubk = EVP_PKEY_CTX_get0_peerkey(ctx);
 		EVP_PKEY *mykey = EVP_PKEY_CTX_get0_pkey(ctx);
 		*keylen = 32;
 		if (key == NULL) return 1;

 		return make_cp_exchange_key(gost_get0_priv_key(mykey), pubk, key);
 	}

 /* EVP_PKEY_METHOD callback encrypt for
  * GOST R 34.10-94 cryptopro modification
  */


 int pkey_GOST94cp_encrypt(EVP_PKEY_CTX *ctx, unsigned char *out, size_t *outlen, const unsigned char* key, size_t key_len )
 	{
 	GOST_KEY_TRANSPORT *gkt=NULL;
 	unsigned char shared_key[32], ukm[8],crypted_key[44];
 	const struct gost_cipher_info *param=get_encryption_params(NULL);
 	EVP_PKEY *pubk = EVP_PKEY_CTX_get0_pkey(ctx);
 	struct gost_pmeth_data *data = EVP_PKEY_CTX_get_data(ctx);
 	gost_ctx cctx;
 	int key_is_ephemeral=1;
 	EVP_PKEY *mykey = EVP_PKEY_CTX_get0_peerkey(ctx);

 	/* Do not use vizir cipher parameters with cryptopro */
 	if (!get_gost_engine_param(GOST_PARAM_CRYPT_PARAMS) && param ==  gost_cipher_list)
 		{
 		param= gost_cipher_list+1;
 		}

 	if (mykey)
 		{
 		/* If key already set, it is not ephemeral */
 		key_is_ephemeral=0;
 		if (!gost_get0_priv_key(mykey))
 			{
 			GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
 			GOST_R_NO_PRIVATE_PART_OF_NON_EPHEMERAL_KEYPAIR);
 			goto err;
 			}
 		}
 	else
 		{
 		/* Otherwise generate ephemeral key */
 		key_is_ephemeral = 1;
 		if (out)
 			{
 			mykey = EVP_PKEY_new();
 			EVP_PKEY_assign(mykey, EVP_PKEY_base_id(pubk),DSA_new());
 			EVP_PKEY_copy_parameters(mykey,pubk);
 			if (!gost_sign_keygen(EVP_PKEY_get0(mykey)))
 				{
 				goto err;
 				}
 			}
 		}
 	if (out)
 		make_cp_exchange_key(gost_get0_priv_key(mykey),pubk,shared_key);
 	if (data->shared_ukm)
 		{
 		memcpy(ukm,data->shared_ukm,8);
 		}
 	else if (out)
 		{
 		if (RAND_bytes(ukm,8)<=0)
 			{
 			GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
 					GOST_R_RANDOM_GENERATOR_FAILURE);
 			goto err;
 			}
 		}

 	if (out) {
 		gost_init(&cctx,param->sblock);
 		keyWrapCryptoPro(&cctx,shared_key,ukm,key,crypted_key);
 	}
 	gkt = GOST_KEY_TRANSPORT_new();
 	if (!gkt)
 		{
 		goto memerr;
 		}
 	if(!ASN1_OCTET_STRING_set(gkt->key_agreement_info->eph_iv,
 			ukm,8))
 		{
 		goto memerr;
 		}
 	if (!ASN1_OCTET_STRING_set(gkt->key_info->imit,crypted_key+40,4))
 		{
 		goto memerr;
 		}
 	if (!ASN1_OCTET_STRING_set(gkt->key_info->encrypted_key,crypted_key+8,32))
 		{
 		goto memerr;
 		}
 	if (key_is_ephemeral) {
 	if (!X509_PUBKEY_set(&gkt->key_agreement_info->ephem_key,out?mykey:pubk))
 		{
 		GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,GOST_R_CANNOT_PACK_EPHEMERAL_KEY);
 		goto err;
 		}
 		if (out) EVP_PKEY_free(mykey);
 	}
 	ASN1_OBJECT_free(gkt->key_agreement_info->cipher);
 	gkt->key_agreement_info->cipher = OBJ_nid2obj(param->nid);
 	*outlen = i2d_GOST_KEY_TRANSPORT(gkt,out?&out:NULL);
 	if (*outlen <= 0)
 		{
 		GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,GOST_R_ERROR_PACKING_KEY_TRANSPORT_INFO);
 		goto err;
 		}
 	if (!key_is_ephemeral)
 		{
 		/* Set control "public key from client certificate used" */
 		if (EVP_PKEY_CTX_ctrl(ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 3, NULL) <= 0)
 			{
 			GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
 				GOST_R_CTRL_CALL_FAILED);
 			goto err;
 			}
 		}
 	GOST_KEY_TRANSPORT_free(gkt);
 	return 1;
 	memerr:
 		if (key_is_ephemeral) {
 			EVP_PKEY_free(mykey);
 		}
 	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
 		GOST_R_MALLOC_FAILURE);
 	err:
 	GOST_KEY_TRANSPORT_free(gkt);
 	return -1;
 	}


 /* EVP_PLEY_METHOD callback decrypt for
  * GOST R 34.10-94 cryptopro modification
  */
 int pkey_GOST94cp_decrypt(EVP_PKEY_CTX *ctx, unsigned char *key, size_t *key_len,const unsigned char *in, size_t in_len) {
 	const unsigned char *p = in;
 	GOST_KEY_TRANSPORT *gkt = NULL;
 	unsigned char wrappedKey[44];
 	unsigned char sharedKey[32];
 	gost_ctx cctx;
 	const struct gost_cipher_info *param=NULL;
 	EVP_PKEY *eph_key=NULL, *peerkey=NULL;
 	EVP_PKEY *priv= EVP_PKEY_CTX_get0_pkey(ctx);

 	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_GOST94CP_DECRYPT,GOST_R_ERROR_PARSING_KEY_TRANSPORT_INFO);
 		return 0;
 		}
 	eph_key = X509_PUBKEY_get(gkt->key_agreement_info->ephem_key);
 	if (eph_key)
 		{
 		if (EVP_PKEY_derive_set_peer(ctx, eph_key) <= 0)
 			{
 			GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
 				GOST_R_INCOMPATIBLE_PEER_KEY);
 			goto err;
 			}
 		}
 	else
 		{
 		/* Set control "public key from client certificate used" */
 		if (EVP_PKEY_CTX_ctrl(ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 3, NULL) <= 0)
 			{
 			GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
 				GOST_R_CTRL_CALL_FAILED);
 			goto err;
 			}
 		}
 	peerkey = EVP_PKEY_CTX_get0_peerkey(ctx);
 	if (!peerkey)
 		{
 		GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
 			GOST_R_NO_PEER_KEY);
 		goto err;
 		}

 	param = get_encryption_params(gkt->key_agreement_info->cipher);
     if(!param){
         goto err;
     }

 	gost_init(&cctx,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);
 	make_cp_exchange_key(gost_get0_priv_key(priv),peerkey,sharedKey);
 	if (!keyUnwrapCryptoPro(&cctx,sharedKey,wrappedKey,key))
 		{
 		GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
 			GOST_R_ERROR_COMPUTING_SHARED_KEY);
 		goto err;
 		}

 	EVP_PKEY_free(eph_key);
 	GOST_KEY_TRANSPORT_free(gkt);
 	return 1;
 err:
 	EVP_PKEY_free(eph_key);
 	GOST_KEY_TRANSPORT_free(gkt);
 	return -1;
 	}
	/**********************************************************************
	* gost94_keyx.c *
	* Copyright (c) 2005-2006 Cryptocom LTD *
	* This file is distributed under the same license as OpenSSL *
	* *
	* Implements generation and parsing of GOST_KEY_TRANSPORT for *
	* GOST R 34.10-94 algorithms *
	* *
	* Requires OpenSSL 0.9.9 for compilation *
	**********************************************************************/
	#include <string.h>
	#include <openssl/dh.h>
	#include <openssl/rand.h>
	#include <openssl/evp.h>
	#include <openssl/objects.h>

	#include "gost89.h"
	#include "gosthash.h"
	#include "e_gost_err.h"
	#include "gost_keywrap.h"
	#include "gost_lcl.h"
	/* Common functions for both 94 and 2001 key exchange schemes */
	/* Implementation of the Diffi-Hellman key agreement scheme based on
	* GOST-94 keys */

	/* Computes Diffie-Hellman key and stores it into buffer in
	* little-endian byte order as expected by both versions of GOST 94
	* algorithm
	*/
	static int compute_pair_key_le(unsigned char pair_key,BIGNUM pub_key,DH *dh)
	{
	unsigned char be_key[128];
	int i,key_size;
	key_size=DH_compute_key(be_key,pub_key,dh);
	if (!key_size) return 0;
	memset(pair_key,0,128);
	for (i=0;i<key_size;i++)
	{
	pair_key[i]=be_key[key_size-1-i];
	}
	return key_size;
	}

	/*
	* Computes 256 bit Key exchange key as specified in RFC 4357
	*/
	static int make_cp_exchange_key(BIGNUM priv_key,EVP_PKEY pubk, unsigned char *shared_key)
	{
	unsigned char dh_key [128];
	int ret;
	gost_hash_ctx hash_ctx;
	DH *dh = DH_new();

	if (!dh)
	return 0;
	memset(dh_key,0,128);
	dh->g = BN_dup(pubk->pkey.dsa->g);
	dh->p = BN_dup(pubk->pkey.dsa->p);
	dh->priv_key = BN_dup(priv_key);
	ret=compute_pair_key_le(dh_key,((DSA *)(EVP_PKEY_get0(pubk)))->pub_key,dh) ;
	DH_free(dh);
	if (!ret) return 0;
	init_gost_hash_ctx(&hash_ctx,&GostR3411_94_CryptoProParamSet);
	start_hash(&hash_ctx);
	hash_block(&hash_ctx,dh_key,128);
	finish_hash(&hash_ctx,shared_key);
	done_gost_hash_ctx(&hash_ctx);
	return 1;
	}

	/* EVP_PKEY_METHOD callback derive. Implements VKO R 34.10-94 */

	int pkey_gost94_derive(EVP_PKEY_CTX ctx,unsigned char key,size_t *keylen)
	{
	EVP_PKEY *pubk = EVP_PKEY_CTX_get0_peerkey(ctx);
	EVP_PKEY *mykey = EVP_PKEY_CTX_get0_pkey(ctx);
	*keylen = 32;
	if (key == NULL) return 1;

	return make_cp_exchange_key(gost_get0_priv_key(mykey), pubk, key);
	}

	/* EVP_PKEY_METHOD callback encrypt for
	* GOST R 34.10-94 cryptopro modification
	*/


	int pkey_GOST94cp_encrypt(EVP_PKEY_CTX ctx, unsigned char out, size_t outlen, const unsigned char key, size_t key_len )
	{
	GOST_KEY_TRANSPORT *gkt=NULL;
	unsigned char shared_key[32], ukm[8],crypted_key[44];
	const struct gost_cipher_info *param=get_encryption_params(NULL);
	EVP_PKEY *pubk = EVP_PKEY_CTX_get0_pkey(ctx);
	struct gost_pmeth_data *data = EVP_PKEY_CTX_get_data(ctx);
	gost_ctx cctx;
	int key_is_ephemeral=1;
	EVP_PKEY *mykey = EVP_PKEY_CTX_get0_peerkey(ctx);

	/* Do not use vizir cipher parameters with cryptopro */
	if (!get_gost_engine_param(GOST_PARAM_CRYPT_PARAMS) && param == gost_cipher_list)
	{
	param= gost_cipher_list+1;
	}

	if (mykey)
	{
	/* If key already set, it is not ephemeral */
	key_is_ephemeral=0;
	if (!gost_get0_priv_key(mykey))
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
	GOST_R_NO_PRIVATE_PART_OF_NON_EPHEMERAL_KEYPAIR);
	goto err;
	}
	}
	else
	{
	/* Otherwise generate ephemeral key */
	key_is_ephemeral = 1;
	if (out)
	{
	mykey = EVP_PKEY_new();
	EVP_PKEY_assign(mykey, EVP_PKEY_base_id(pubk),DSA_new());
	EVP_PKEY_copy_parameters(mykey,pubk);
	if (!gost_sign_keygen(EVP_PKEY_get0(mykey)))
	{
	goto err;
	}
	}
	}
	if (out)
	make_cp_exchange_key(gost_get0_priv_key(mykey),pubk,shared_key);
	if (data->shared_ukm)
	{
	memcpy(ukm,data->shared_ukm,8);
	}
	else if (out)
	{
	if (RAND_bytes(ukm,8)<=0)
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
	GOST_R_RANDOM_GENERATOR_FAILURE);
	goto err;
	}
	}

	if (out) {
	gost_init(&cctx,param->sblock);
	keyWrapCryptoPro(&cctx,shared_key,ukm,key,crypted_key);
	}
	gkt = GOST_KEY_TRANSPORT_new();
	if (!gkt)
	{
	goto memerr;
	}
	if(!ASN1_OCTET_STRING_set(gkt->key_agreement_info->eph_iv,
	ukm,8))
	{
	goto memerr;
	}
	if (!ASN1_OCTET_STRING_set(gkt->key_info->imit,crypted_key+40,4))
	{
	goto memerr;
	}
	if (!ASN1_OCTET_STRING_set(gkt->key_info->encrypted_key,crypted_key+8,32))
	{
	goto memerr;
	}
	if (key_is_ephemeral) {
	if (!X509_PUBKEY_set(&gkt->key_agreement_info->ephem_key,out?mykey:pubk))
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,GOST_R_CANNOT_PACK_EPHEMERAL_KEY);
	goto err;
	}
	if (out) EVP_PKEY_free(mykey);
	}
	ASN1_OBJECT_free(gkt->key_agreement_info->cipher);
	gkt->key_agreement_info->cipher = OBJ_nid2obj(param->nid);
	*outlen = i2d_GOST_KEY_TRANSPORT(gkt,out?&out:NULL);
	if (*outlen <= 0)
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,GOST_R_ERROR_PACKING_KEY_TRANSPORT_INFO);
	goto err;
	}
	if (!key_is_ephemeral)
	{
	/* Set control "public key from client certificate used" */
	if (EVP_PKEY_CTX_ctrl(ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 3, NULL) <= 0)
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
	GOST_R_CTRL_CALL_FAILED);
	goto err;
	}
	}
	GOST_KEY_TRANSPORT_free(gkt);
	return 1;
	memerr:
	if (key_is_ephemeral) {
	EVP_PKEY_free(mykey);
	}
	GOSTerr(GOST_F_PKEY_GOST94CP_ENCRYPT,
	GOST_R_MALLOC_FAILURE);
	err:
	GOST_KEY_TRANSPORT_free(gkt);
	return -1;
	}


	/* EVP_PLEY_METHOD callback decrypt for
	* GOST R 34.10-94 cryptopro modification
	*/
	int pkey_GOST94cp_decrypt(EVP_PKEY_CTX ctx, unsigned char key, size_t key_len,const unsigned char in, size_t in_len) {
	const unsigned char *p = in;
	GOST_KEY_TRANSPORT *gkt = NULL;
	unsigned char wrappedKey[44];
	unsigned char sharedKey[32];
	gost_ctx cctx;
	const struct gost_cipher_info *param=NULL;
	EVP_PKEY eph_key=NULL, peerkey=NULL;
	EVP_PKEY *priv= EVP_PKEY_CTX_get0_pkey(ctx);

	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_GOST94CP_DECRYPT,GOST_R_ERROR_PARSING_KEY_TRANSPORT_INFO);
	return 0;
	}
	eph_key = X509_PUBKEY_get(gkt->key_agreement_info->ephem_key);
	if (eph_key)
	{
	if (EVP_PKEY_derive_set_peer(ctx, eph_key) <= 0)
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
	GOST_R_INCOMPATIBLE_PEER_KEY);
	goto err;
	}
	}
	else
	{
	/* Set control "public key from client certificate used" */
	if (EVP_PKEY_CTX_ctrl(ctx, -1, -1, EVP_PKEY_CTRL_PEER_KEY, 3, NULL) <= 0)
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
	GOST_R_CTRL_CALL_FAILED);
	goto err;
	}
	}
	peerkey = EVP_PKEY_CTX_get0_peerkey(ctx);
	if (!peerkey)
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
	GOST_R_NO_PEER_KEY);
	goto err;
	}

	param = get_encryption_params(gkt->key_agreement_info->cipher);
	if(!param){
	goto err;
	}

	gost_init(&cctx,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);
	make_cp_exchange_key(gost_get0_priv_key(priv),peerkey,sharedKey);
	if (!keyUnwrapCryptoPro(&cctx,sharedKey,wrappedKey,key))
	{
	GOSTerr(GOST_F_PKEY_GOST94CP_DECRYPT,
	GOST_R_ERROR_COMPUTING_SHARED_KEY);
	goto err;
	}

	EVP_PKEY_free(eph_key);
	GOST_KEY_TRANSPORT_free(gkt);
	return 1;
	err:
	EVP_PKEY_free(eph_key);
	GOST_KEY_TRANSPORT_free(gkt);
	return -1;
	}