diff options
Diffstat (limited to 'engines/ccgost/gost94_keyx.c')
| -rw-r--r-- | engines/ccgost/gost94_keyx.c | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/engines/ccgost/gost94_keyx.c b/engines/ccgost/gost94_keyx.c new file mode 100644 index 000000000..a183edbe8 --- /dev/null +++ b/engines/ccgost/gost94_keyx.c @@ -0,0 +1,287 @@ +/********************************************************************** + * 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); + 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; + } + |