text: /**********************************************************************
   *                          gost_ameth.c                              *
   *             Copyright (c) 2005-2006 Cryptocom LTD                  *
   *         This file is distributed under the same license as OpenSSL *
   *                                                                    *
   *       Implementation of RFC 4490/4491 ASN1 method                  *
   *       for OpenSSL                                                  *
   *          Requires OpenSSL 0.9.9 for compilation                    *
   **********************************************************************/
  #include <string.h>
  #include <openssl/crypto.h>
  #include <openssl/err.h>
  #include <openssl/engine.h>
  #include <openssl/evp.h>
  #include <openssl/asn1.h>
  #ifndef OPENSSL_NO_CMS
  # include <openssl/cms.h>
  #endif
  #include "gost_params.h"
  #include "gost_lcl.h"
  #include "e_gost_err.h"
  
  int gost94_nid_by_params(DSA *p)
  {
      R3410_params *gost_params;
      BIGNUM *q = BN_new();
      for (gost_params = R3410_paramset; gost_params->q != NULL; gost_params++) {
          BN_dec2bn(&q, gost_params->q);
          if (!BN_cmp(q, p->q)) {
              BN_free(q);
              return gost_params->nid;
          }
      }
      BN_free(q);
      return NID_undef;
  }
  
  static ASN1_STRING *encode_gost_algor_params(const EVP_PKEY *key)
  {
      ASN1_STRING *params = ASN1_STRING_new();
      GOST_KEY_PARAMS *gkp = GOST_KEY_PARAMS_new();
      int pkey_param_nid = NID_undef;
  
      if (!params || !gkp) {
          GOSTerr(GOST_F_ENCODE_GOST_ALGOR_PARAMS, ERR_R_MALLOC_FAILURE);
          ASN1_STRING_free(params);
          params = NULL;
          goto err;
      }
      switch (EVP_PKEY_base_id(key)) {
      case NID_id_GostR3410_2001:
          pkey_param_nid =
              EC_GROUP_get_curve_name(EC_KEY_get0_group
                                      (EVP_PKEY_get0((EVP_PKEY *)key)));
          break;
      case NID_id_GostR3410_94:
          pkey_param_nid =
              (int)gost94_nid_by_params(EVP_PKEY_get0((EVP_PKEY *)key));
          if (pkey_param_nid == NID_undef) {
              GOSTerr(GOST_F_ENCODE_GOST_ALGOR_PARAMS,
                      GOST_R_INVALID_GOST94_PARMSET);
              ASN1_STRING_free(params);
              params = NULL;
              goto err;
          }
          break;
      }
      gkp->key_params = OBJ_nid2obj(pkey_param_nid);
      gkp->hash_params = OBJ_nid2obj(NID_id_GostR3411_94_CryptoProParamSet);
      /*
       * gkp->cipher_params = OBJ_nid2obj(cipher_param_nid);
       */
      params->length = i2d_GOST_KEY_PARAMS(gkp, &params->data);
      if (params->length <= 0) {
          GOSTerr(GOST_F_ENCODE_GOST_ALGOR_PARAMS, ERR_R_MALLOC_FAILURE);
          ASN1_STRING_free(params);
          params = NULL;
          goto err;
      }
      params->type = V_ASN1_SEQUENCE;
   err:
      GOST_KEY_PARAMS_free(gkp);
      return params;
  }
  
  /*
   * Parses GOST algorithm parameters from X509_ALGOR and modifies pkey setting
   * NID and parameters
   */
  static int decode_gost_algor_params(EVP_PKEY *pkey, X509_ALGOR *palg)
  {
      ASN1_OBJECT *palg_obj = NULL;
      int ptype = V_ASN1_UNDEF;
      int pkey_nid = NID_undef, param_nid = NID_undef;
      void *_pval;
      ASN1_STRING *pval = NULL;
      const unsigned char *p;
      GOST_KEY_PARAMS *gkp = NULL;
  
      X509_ALGOR_get0(&palg_obj, &ptype, &_pval, palg);
      pval = _pval;
      if (ptype != V_ASN1_SEQUENCE) {
          GOSTerr(GOST_F_DECODE_GOST_ALGOR_PARAMS,
                  GOST_R_BAD_KEY_PARAMETERS_FORMAT);
          return 0;
      }
      p = pval->data;
      pkey_nid = OBJ_obj2nid(palg_obj);
  
      gkp = d2i_GOST_KEY_PARAMS(NULL, &p, pval->length);
      if (!gkp) {
          GOSTerr(GOST_F_DECODE_GOST_ALGOR_PARAMS,
                  GOST_R_BAD_PKEY_PARAMETERS_FORMAT);
          return 0;
      }
      param_nid = OBJ_obj2nid(gkp->key_params);
      GOST_KEY_PARAMS_free(gkp);
      if(!EVP_PKEY_set_type(pkey, pkey_nid)) {
          GOSTerr(GOST_F_DECODE_GOST_ALGOR_PARAMS, ERR_R_INTERNAL_ERROR);
          return 0;
      }
      switch (pkey_nid) {
      case NID_id_GostR3410_94:
          {
              DSA *dsa = EVP_PKEY_get0(pkey);
              if (!dsa) {
                  dsa = DSA_new();
                  if (!EVP_PKEY_assign(pkey, pkey_nid, dsa))
                      return 0;
              }
              if (!fill_GOST94_params(dsa, param_nid))
                  return 0;
              break;
          }
      case NID_id_GostR3410_2001:
          {
              EC_KEY *ec = EVP_PKEY_get0(pkey);
              if (!ec) {
                  ec = EC_KEY_new();
                  if (!EVP_PKEY_assign(pkey, pkey_nid, ec))
                      return 0;
              }
              if (!fill_GOST2001_params(ec, param_nid))
                  return 0;
          }
      }
  
      return 1;
  }
  
  static int gost_set_priv_key(EVP_PKEY *pkey, BIGNUM *priv)
  {
      switch (EVP_PKEY_base_id(pkey)) {
      case NID_id_GostR3410_94:
          {
              DSA *dsa = EVP_PKEY_get0(pkey);
              if (!dsa) {
                  dsa = DSA_new();
                  EVP_PKEY_assign(pkey, EVP_PKEY_base_id(pkey), dsa);
              }
              dsa->priv_key = BN_dup(priv);
              if (!EVP_PKEY_missing_parameters(pkey))
                  gost94_compute_public(dsa);
              break;
          }
      case NID_id_GostR3410_2001:
          {
              EC_KEY *ec = EVP_PKEY_get0(pkey);
              if (!ec) {
                  ec = EC_KEY_new();
                  EVP_PKEY_assign(pkey, EVP_PKEY_base_id(pkey), ec);
              }
              if (!EC_KEY_set_private_key(ec, priv))
                  return 0;
              if (!EVP_PKEY_missing_parameters(pkey))
                  gost2001_compute_public(ec);
              break;
          }
      }
      return 1;
  }
  
  BIGNUM *gost_get0_priv_key(const EVP_PKEY *pkey)
  {
      switch (EVP_PKEY_base_id(pkey)) {
      case NID_id_GostR3410_94:
          {
              DSA *dsa = EVP_PKEY_get0((EVP_PKEY *)pkey);
              if (!dsa) {
                  return NULL;
              }
              if (!dsa->priv_key)
                  return NULL;
              return dsa->priv_key;
              break;
          }
      case NID_id_GostR3410_2001:
          {
              EC_KEY *ec = EVP_PKEY_get0((EVP_PKEY *)pkey);
              const BIGNUM *priv;
              if (!ec) {
                  return NULL;
              }
              if (!(priv = EC_KEY_get0_private_key(ec)))
                  return NULL;
              return (BIGNUM *)priv;
              break;
          }
      }
      return NULL;
  }
  
  static int pkey_ctrl_gost(EVP_PKEY *pkey, int op, long arg1, void *arg2)
  {
      switch (op) {
      case ASN1_PKEY_CTRL_PKCS7_SIGN:
          if (arg1 == 0) {
              X509_ALGOR *alg1 = NULL, *alg2 = NULL;
              int nid = EVP_PKEY_base_id(pkey);
              PKCS7_SIGNER_INFO_get0_algs((PKCS7_SIGNER_INFO *)arg2,
                                          NULL, &alg1, &alg2);
              X509_ALGOR_set0(alg1, OBJ_nid2obj(NID_id_GostR3411_94),
                              V_ASN1_NULL, 0);
              if (nid == NID_undef) {
                  return (-1);
              }
              X509_ALGOR_set0(alg2, OBJ_nid2obj(nid), V_ASN1_NULL, 0);
          }
          return 1;
  #ifndef OPENSSL_NO_CMS
      case ASN1_PKEY_CTRL_CMS_SIGN:
          if (arg1 == 0) {
              X509_ALGOR *alg1 = NULL, *alg2 = NULL;
              int nid = EVP_PKEY_base_id(pkey);
              CMS_SignerInfo_get0_algs((CMS_SignerInfo *)arg2,
                                       NULL, NULL, &alg1, &alg2);
              X509_ALGOR_set0(alg1, OBJ_nid2obj(NID_id_GostR3411_94),
                              V_ASN1_NULL, 0);
              if (nid == NID_undef) {
                  return (-1);
              }
              X509_ALGOR_set0(alg2, OBJ_nid2obj(nid), V_ASN1_NULL, 0);
          }
          return 1;
  #endif
      case ASN1_PKEY_CTRL_PKCS7_ENCRYPT:
          if (arg1 == 0) {
              X509_ALGOR *alg;
              ASN1_STRING *params = encode_gost_algor_params(pkey);
              if (!params) {
                  return -1;
              }
              PKCS7_RECIP_INFO_get0_alg((PKCS7_RECIP_INFO *)arg2, &alg);
              X509_ALGOR_set0(alg, OBJ_nid2obj(pkey->type),
                              V_ASN1_SEQUENCE, params);
          }
          return 1;
  #ifndef OPENSSL_NO_CMS
      case ASN1_PKEY_CTRL_CMS_ENVELOPE:
          if (arg1 == 0) {
              X509_ALGOR *alg = NULL;
              ASN1_STRING *params = encode_gost_algor_params(pkey);
              if (!params) {
                  return -1;
              }
              CMS_RecipientInfo_ktri_get0_algs((CMS_RecipientInfo *)arg2, NULL,
                                               NULL, &alg);
              X509_ALGOR_set0(alg, OBJ_nid2obj(pkey->type), V_ASN1_SEQUENCE,
                              params);
          }
          return 1;
  #endif
      case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
          *(int *)arg2 = NID_id_GostR3411_94;
          return 2;
      }
  
      return -2;
  }
  
  /* --------------------- free functions * ------------------------------*/
  static void pkey_free_gost94(EVP_PKEY *key)
  {
      if (key->pkey.dsa) {
          DSA_free(key->pkey.dsa);
      }
  }
  
  static void pkey_free_gost01(EVP_PKEY *key)
  {
      if (key->pkey.ec) {
          EC_KEY_free(key->pkey.ec);
      }
  }
  
  /* ------------------ private key functions  -----------------------------*/
  static int priv_decode_gost(EVP_PKEY *pk, PKCS8_PRIV_KEY_INFO *p8inf)
  {
      const unsigned char *pkey_buf = NULL, *p = NULL;
      int priv_len = 0;
      BIGNUM *pk_num = NULL;
      int ret = 0;
      X509_ALGOR *palg = NULL;
      ASN1_OBJECT *palg_obj = NULL;
      ASN1_INTEGER *priv_key = NULL;
  
      if (!PKCS8_pkey_get0(&palg_obj, &pkey_buf, &priv_len, &palg, p8inf))
          return 0;
      p = pkey_buf;
      if (!decode_gost_algor_params(pk, palg)) {
          return 0;
      }
      if (V_ASN1_OCTET_STRING == *p) {
          /* New format - Little endian octet string */
          unsigned char rev_buf[32];
          int i;
          ASN1_OCTET_STRING *s = d2i_ASN1_OCTET_STRING(NULL, &p, priv_len);
          if (!s || s->length != 32) {
              GOSTerr(GOST_F_PRIV_DECODE_GOST, EVP_R_DECODE_ERROR);
              return 0;
          }
          for (i = 0; i < 32; i++) {
              rev_buf[31 - i] = s->data[i];
          }
          ASN1_STRING_free(s);
          pk_num = getbnfrombuf(rev_buf, 32);
      } else {
          priv_key = d2i_ASN1_INTEGER(NULL, &p, priv_len);
          if (!priv_key)
              return 0;
          ret = ((pk_num = ASN1_INTEGER_to_BN(priv_key, NULL)) != NULL);
          ASN1_INTEGER_free(priv_key);
          if (!ret) {
              GOSTerr(GOST_F_PRIV_DECODE_GOST, EVP_R_DECODE_ERROR);
              return 0;
          }
      }
  
      ret = gost_set_priv_key(pk, pk_num);
      BN_free(pk_num);
      return ret;
  }
  
  /* ----------------------------------------------------------------------*/
  static int priv_encode_gost(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pk)
  {
      ASN1_OBJECT *algobj = OBJ_nid2obj(EVP_PKEY_base_id(pk));
      ASN1_STRING *params = encode_gost_algor_params(pk);
      unsigned char *priv_buf = NULL;
      int priv_len;
  
      ASN1_INTEGER *asn1key = NULL;
      if (!params) {
          return 0;
      }
      asn1key = BN_to_ASN1_INTEGER(gost_get0_priv_key(pk), NULL);
      priv_len = i2d_ASN1_INTEGER(asn1key, &priv_buf);
      ASN1_INTEGER_free(asn1key);
      return PKCS8_pkey_set0(p8, algobj, 0, V_ASN1_SEQUENCE, params,
                             priv_buf, priv_len);
  }
  
  /* --------- printing keys --------------------------------*/
  static int print_gost_94(BIO *out, const EVP_PKEY *pkey, int indent,
                           ASN1_PCTX *pctx, int type)
  {
      int param_nid = NID_undef;
  
      if (type == 2) {
          BIGNUM *key;
  
          if (!BIO_indent(out, indent, 128))
              return 0;
          BIO_printf(out, "Private key: ");
          key = gost_get0_priv_key(pkey);
          if (!key)
              BIO_printf(out, "<undefined>");
          else
              BN_print(out, key);
          BIO_printf(out, "\n");
      }
      if (type >= 1) {
          BIGNUM *pubkey;
  
          pubkey = ((DSA *)EVP_PKEY_get0((EVP_PKEY *)pkey))->pub_key;
          BIO_indent(out, indent, 128);
          BIO_printf(out, "Public key: ");
          BN_print(out, pubkey);
          BIO_printf(out, "\n");
      }
  
      param_nid = gost94_nid_by_params(EVP_PKEY_get0((EVP_PKEY *)pkey));
      BIO_indent(out, indent, 128);
      BIO_printf(out, "Parameter set: %s\n", OBJ_nid2ln(param_nid));
      return 1;
  }
  
  static int param_print_gost94(BIO *out, const EVP_PKEY *pkey, int indent,
                                ASN1_PCTX *pctx)
  {
      return print_gost_94(out, pkey, indent, pctx, 0);
  }
  
  static int pub_print_gost94(BIO *out, const EVP_PKEY *pkey, int indent,
                              ASN1_PCTX *pctx)
  {
      return print_gost_94(out, pkey, indent, pctx, 1);
  }
  
  static int priv_print_gost94(BIO *out, const EVP_PKEY *pkey, int indent,
                               ASN1_PCTX *pctx)
  {
      return print_gost_94(out, pkey, indent, pctx, 2);
  }
  
  static int print_gost_01(BIO *out, const EVP_PKEY *pkey, int indent,
                           ASN1_PCTX *pctx, int type)
  {
      int param_nid = NID_undef;
      if (type == 2) {
          BIGNUM *key;
  
          if (!BIO_indent(out, indent, 128))
              return 0;
          BIO_printf(out, "Private key: ");
          key = gost_get0_priv_key(pkey);
          if (!key)
              BIO_printf(out, "<undefined)");
          else
              BN_print(out, key);
          BIO_printf(out, "\n");
      }
      if (type >= 1) {
          BN_CTX *ctx = BN_CTX_new();
          BIGNUM *X, *Y;
          const EC_POINT *pubkey;
          const EC_GROUP *group;
  
          if (!ctx) {
              GOSTerr(GOST_F_PRINT_GOST_01, ERR_R_MALLOC_FAILURE);
              return 0;
          }
          BN_CTX_start(ctx);
          X = BN_CTX_get(ctx);
          Y = BN_CTX_get(ctx);
          pubkey =
              EC_KEY_get0_public_key((EC_KEY *)EVP_PKEY_get0((EVP_PKEY *)pkey));
          group = EC_KEY_get0_group((EC_KEY *)EVP_PKEY_get0((EVP_PKEY *)pkey));
          if (!EC_POINT_get_affine_coordinates_GFp(group, pubkey, X, Y, ctx)) {
              GOSTerr(GOST_F_PRINT_GOST_01, ERR_R_EC_LIB);
              BN_CTX_free(ctx);
              return 0;
          }
          if (!BIO_indent(out, indent, 128))
              return 0;
          BIO_printf(out, "Public key:\n");
          if (!BIO_indent(out, indent + 3, 128))
              return 0;
          BIO_printf(out, "X:");
          BN_print(out, X);
          BIO_printf(out, "\n");
          BIO_indent(out, indent + 3, 128);
          BIO_printf(out, "Y:");
          BN_print(out, Y);
          BIO_printf(out, "\n");
          BN_CTX_end(ctx);
          BN_CTX_free(ctx);
      }
  
      param_nid =
          EC_GROUP_get_curve_name(EC_KEY_get0_group
                                  (EVP_PKEY_get0((EVP_PKEY *)pkey)));
      if (!BIO_indent(out, indent, 128))
          return 0;
      BIO_printf(out, "Parameter set: %s\n", OBJ_nid2ln(param_nid));
      return 1;
  }
  
  static int param_print_gost01(BIO *out, const EVP_PKEY *pkey, int indent,
                                ASN1_PCTX *pctx)
  {
      return print_gost_01(out, pkey, indent, pctx, 0);
  }
  
  static int pub_print_gost01(BIO *out, const EVP_PKEY *pkey, int indent,
                              ASN1_PCTX *pctx)
  {
      return print_gost_01(out, pkey, indent, pctx, 1);
  }
  
  static int priv_print_gost01(BIO *out, const EVP_PKEY *pkey, int indent,
                               ASN1_PCTX *pctx)
  {
      return print_gost_01(out, pkey, indent, pctx, 2);
  }
  
  /* ---------------------------------------------------------------------*/
  static int param_missing_gost94(const EVP_PKEY *pk)
  {
      const DSA *dsa = EVP_PKEY_get0((EVP_PKEY *)pk);
      if (!dsa)
          return 1;
      if (!dsa->q)
          return 1;
      return 0;
  }
  
  static int param_missing_gost01(const EVP_PKEY *pk)
  {
      const EC_KEY *ec = EVP_PKEY_get0((EVP_PKEY *)pk);
      if (!ec)
          return 1;
      if (!EC_KEY_get0_group(ec))
          return 1;
      return 0;
  }
  
  static int param_copy_gost94(EVP_PKEY *to, const EVP_PKEY *from)
  {
      const DSA *dfrom = EVP_PKEY_get0((EVP_PKEY *)from);
      DSA *dto = EVP_PKEY_get0(to);
      if (EVP_PKEY_base_id(from) != EVP_PKEY_base_id(to)) {
          GOSTerr(GOST_F_PARAM_COPY_GOST94, GOST_R_INCOMPATIBLE_ALGORITHMS);
          return 0;
      }
      if (!dfrom) {
          GOSTerr(GOST_F_PARAM_COPY_GOST94, GOST_R_KEY_PARAMETERS_MISSING);
          return 0;
      }
      if (!dto) {
          dto = DSA_new();
          EVP_PKEY_assign(to, EVP_PKEY_base_id(from), dto);
      }
  #define COPYBIGNUM(a,b,x) if (a->x) BN_free(a->x); a->x=BN_dup(b->x);
      COPYBIGNUM(dto, dfrom, p)
          COPYBIGNUM(dto, dfrom, q)
          COPYBIGNUM(dto, dfrom, g)
  
          if (dto->priv_key)
          gost94_compute_public(dto);
      return 1;
  }
  
  static int param_copy_gost01(EVP_PKEY *to, const EVP_PKEY *from)
  {
      EC_KEY *eto = EVP_PKEY_get0(to);
      const EC_KEY *efrom = EVP_PKEY_get0((EVP_PKEY *)from);
      if (EVP_PKEY_base_id(from) != EVP_PKEY_base_id(to)) {
          GOSTerr(GOST_F_PARAM_COPY_GOST01, GOST_R_INCOMPATIBLE_ALGORITHMS);
          return 0;
      }
      if (!efrom) {
          GOSTerr(GOST_F_PARAM_COPY_GOST01, GOST_R_KEY_PARAMETERS_MISSING);
          return 0;
      }
      if (!eto) {
          eto = EC_KEY_new();
          if(!eto) {
              GOSTerr(GOST_F_PARAM_COPY_GOST01, ERR_R_MALLOC_FAILURE);
              return 0;
          }
          if(!EVP_PKEY_assign(to, EVP_PKEY_base_id(from), eto)) {
              GOSTerr(GOST_F_PARAM_COPY_GOST01, ERR_R_INTERNAL_ERROR);
              return 0;
          }
      }
      if(!EC_KEY_set_group(eto, EC_KEY_get0_group(efrom))) {
          GOSTerr(GOST_F_PARAM_COPY_GOST01, ERR_R_INTERNAL_ERROR);
          return 0;
      }
      if (EC_KEY_get0_private_key(eto)) {
          gost2001_compute_public(eto);
      }
      return 1;
  }
  
  static int param_cmp_gost94(const EVP_PKEY *a, const EVP_PKEY *b)
  {
      const DSA *da = EVP_PKEY_get0((EVP_PKEY *)a);
      const DSA *db = EVP_PKEY_get0((EVP_PKEY *)b);
      if (!BN_cmp(da->q, db->q))
          return 1;
      return 0;
  }
  
  static int param_cmp_gost01(const EVP_PKEY *a, const EVP_PKEY *b)
  {
      if (EC_GROUP_get_curve_name
          (EC_KEY_get0_group(EVP_PKEY_get0((EVP_PKEY *)a))) ==
          EC_GROUP_get_curve_name(EC_KEY_get0_group
                                  (EVP_PKEY_get0((EVP_PKEY *)b)))) {
          return 1;
      }
      return 0;
  
  }
  
  /* ---------- Public key functions * --------------------------------------*/
  static int pub_decode_gost94(EVP_PKEY *pk, X509_PUBKEY *pub)
  {
      X509_ALGOR *palg = NULL;
      const unsigned char *pubkey_buf = NULL;
      unsigned char *databuf;
      ASN1_OBJECT *palgobj = NULL;
      int pub_len, i, j;
      DSA *dsa;
      ASN1_OCTET_STRING *octet = NULL;
  
      if (!X509_PUBKEY_get0_param(&palgobj, &pubkey_buf, &pub_len, &palg, pub))
          return 0;
      EVP_PKEY_assign(pk, OBJ_obj2nid(palgobj), NULL);
      if (!decode_gost_algor_params(pk, palg))
          return 0;
      octet = d2i_ASN1_OCTET_STRING(NULL, &pubkey_buf, pub_len);
      if (!octet) {
          GOSTerr(GOST_F_PUB_DECODE_GOST94, ERR_R_MALLOC_FAILURE);
          return 0;
      }
      databuf = OPENSSL_malloc(octet->length);
      for (i = 0, j = octet->length - 1; i < octet->length; i++, j--) {
          databuf[j] = octet->data[i];
      }
      dsa = EVP_PKEY_get0(pk);
      dsa->pub_key = BN_bin2bn(databuf, octet->length, NULL);
      ASN1_OCTET_STRING_free(octet);
      OPENSSL_free(databuf);
      return 1;
  
  }
  
  static int pub_encode_gost94(X509_PUBKEY *pub, const EVP_PKEY *pk)
  {
      ASN1_OBJECT *algobj = NULL;
      ASN1_OCTET_STRING *octet = NULL;
      void *pval = NULL;
      unsigned char *buf = NULL, *databuf, *sptr;
      int i, j, data_len, ret = 0;
  
      int ptype = V_ASN1_UNDEF;
      DSA *dsa = EVP_PKEY_get0((EVP_PKEY *)pk);
      algobj = OBJ_nid2obj(EVP_PKEY_base_id(pk));
      if (pk->save_parameters) {
          ASN1_STRING *params = encode_gost_algor_params(pk);
          pval = params;
          ptype = V_ASN1_SEQUENCE;
      }
      data_len = BN_num_bytes(dsa->pub_key);
      databuf = OPENSSL_malloc(data_len);
      BN_bn2bin(dsa->pub_key, databuf);
      octet = ASN1_OCTET_STRING_new();
      ASN1_STRING_set(octet, NULL, data_len);
      sptr = ASN1_STRING_data(octet);
      for (i = 0, j = data_len - 1; i < data_len; i++, j--) {
          sptr[i] = databuf[j];
      }
      OPENSSL_free(databuf);
      ret = i2d_ASN1_OCTET_STRING(octet, &buf);
      ASN1_BIT_STRING_free(octet);
      if (ret < 0)
          return 0;
      return X509_PUBKEY_set0_param(pub, algobj, ptype, pval, buf, ret);
  }
  
  static int pub_decode_gost01(EVP_PKEY *pk, X509_PUBKEY *pub)
  {
      X509_ALGOR *palg = NULL;
      const unsigned char *pubkey_buf = NULL;
      unsigned char *databuf;
      ASN1_OBJECT *palgobj = NULL;
      int pub_len, i, j;
      EC_POINT *pub_key;
      BIGNUM *X, *Y;
      ASN1_OCTET_STRING *octet = NULL;
      int len;
      const EC_GROUP *group;
  
      if (!X509_PUBKEY_get0_param(&palgobj, &pubkey_buf, &pub_len, &palg, pub))
          return 0;
      EVP_PKEY_assign(pk, OBJ_obj2nid(palgobj), NULL);
      if (!decode_gost_algor_params(pk, palg))
          return 0;
      group = EC_KEY_get0_group(EVP_PKEY_get0(pk));
      octet = d2i_ASN1_OCTET_STRING(NULL, &pubkey_buf, pub_len);
      if (!octet) {
          GOSTerr(GOST_F_PUB_DECODE_GOST01, ERR_R_MALLOC_FAILURE);
          return 0;
      }
      databuf = OPENSSL_malloc(octet->length);
      for (i = 0, j = octet->length - 1; i < octet->length; i++, j--) {
          databuf[j] = octet->data[i];
      }
      len = octet->length / 2;
      ASN1_OCTET_STRING_free(octet);
  
      Y = getbnfrombuf(databuf, len);
      X = getbnfrombuf(databuf + len, len);
      OPENSSL_free(databuf);
      pub_key = EC_POINT_new(group);
      if (!EC_POINT_set_affine_coordinates_GFp(group, pub_key, X, Y, NULL)) {
          GOSTerr(GOST_F_PUB_DECODE_GOST01, ERR_R_EC_LIB);
          EC_POINT_free(pub_key);
          BN_free(X);
          BN_free(Y);
          return 0;
      }
      BN_free(X);
      BN_free(Y);
      if (!EC_KEY_set_public_key(EVP_PKEY_get0(pk), pub_key)) {
          GOSTerr(GOST_F_PUB_DECODE_GOST01, ERR_R_EC_LIB);
          EC_POINT_free(pub_key);
          return 0;
      }
      EC_POINT_free(pub_key);
      return 1;
  
  }
  
  static int pub_encode_gost01(X509_PUBKEY *pub, const EVP_PKEY *pk)
  {
      ASN1_OBJECT *algobj = NULL;
      ASN1_OCTET_STRING *octet = NULL;
      void *pval = NULL;
      unsigned char *buf = NULL, *databuf, *sptr;
      int i, j, data_len, ret = 0;
      const EC_POINT *pub_key;
      BIGNUM *X, *Y, *order;
      const EC_KEY *ec = EVP_PKEY_get0((EVP_PKEY *)pk);
      int ptype = V_ASN1_UNDEF;
  
      algobj = OBJ_nid2obj(EVP_PKEY_base_id(pk));
      if (pk->save_parameters) {
          ASN1_STRING *params = encode_gost_algor_params(pk);
          pval = params;
          ptype = V_ASN1_SEQUENCE;
      }
      order = BN_new();
      EC_GROUP_get_order(EC_KEY_get0_group(ec), order, NULL);
      pub_key = EC_KEY_get0_public_key(ec);
      if (!pub_key) {
          GOSTerr(GOST_F_PUB_ENCODE_GOST01, GOST_R_PUBLIC_KEY_UNDEFINED);
          return 0;
      }
      X = BN_new();
      Y = BN_new();
      if(!X || !Y) {
          GOSTerr(GOST_F_PUB_ENCODE_GOST01, ERR_R_MALLOC_FAILURE);
          if(X) BN_free(X);
          if(Y) BN_free(Y);
          BN_free(order);
          return 0;
      }
      if(!EC_POINT_get_affine_coordinates_GFp(EC_KEY_get0_group(ec),
                                          pub_key, X, Y, NULL)) {
          GOSTerr(GOST_F_PUB_ENCODE_GOST01, ERR_R_INTERNAL_ERROR);
          BN_free(X);
          BN_free(Y);
          BN_free(order);
          return 0;
      }
      data_len = 2 * BN_num_bytes(order);
      BN_free(order);
      databuf = OPENSSL_malloc(data_len);
      memset(databuf, 0, data_len);
  
      store_bignum(X, databuf + data_len / 2, data_len / 2);
      store_bignum(Y, databuf, data_len / 2);
  
      BN_free(X);
      BN_free(Y);
      octet = ASN1_OCTET_STRING_new();
      ASN1_STRING_set(octet, NULL, data_len);
      sptr = ASN1_STRING_data(octet);
      for (i = 0, j = data_len - 1; i < data_len; i++, j--) {
          sptr[i] = databuf[j];
      }
      OPENSSL_free(databuf);
      ret = i2d_ASN1_OCTET_STRING(octet, &buf);
      ASN1_BIT_STRING_free(octet);
      if (ret < 0)
          return 0;
      return X509_PUBKEY_set0_param(pub, algobj, ptype, pval, buf, ret);
  }
  
  static int pub_cmp_gost94(const EVP_PKEY *a, const EVP_PKEY *b)
  {
      const DSA *da = EVP_PKEY_get0((EVP_PKEY *)a);
      const DSA *db = EVP_PKEY_get0((EVP_PKEY *)b);
      if (da && db && da->pub_key && db->pub_key
          && !BN_cmp(da->pub_key, db->pub_key)) {
          return 1;
      }
      return 0;
  }
  
  static int pub_cmp_gost01(const EVP_PKEY *a, const EVP_PKEY *b)
  {
      const EC_KEY *ea = EVP_PKEY_get0((EVP_PKEY *)a);
      const EC_KEY *eb = EVP_PKEY_get0((EVP_PKEY *)b);
      const EC_POINT *ka, *kb;
      int ret = 0;
      if (!ea || !eb)
          return 0;
      ka = EC_KEY_get0_public_key(ea);
      kb = EC_KEY_get0_public_key(eb);
      if (!ka || !kb)
          return 0;
      ret = (0 == EC_POINT_cmp(EC_KEY_get0_group(ea), ka, kb, NULL));
      return ret;
  }
  
  static int pkey_size_gost(const EVP_PKEY *pk)
  {
      return 64;
  }
  
  static int pkey_bits_gost(const EVP_PKEY *pk)
  {
      return 256;
  }
  
  /* ---------------------- ASN1 METHOD for GOST MAC  -------------------*/
  static void mackey_free_gost(EVP_PKEY *pk)
  {
      if (pk->pkey.ptr) {
          OPENSSL_free(pk->pkey.ptr);
      }
  }
  
  static int mac_ctrl_gost(EVP_PKEY *pkey, int op, long arg1, void *arg2)
  {
      switch (op) {
      case ASN1_PKEY_CTRL_DEFAULT_MD_NID:
          *(int *)arg2 = NID_id_Gost28147_89_MAC;
          return 2;
      }
      return -2;
  }
  
  static int gost94_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
  {
      int nid = gost94_nid_by_params(EVP_PKEY_get0((EVP_PKEY *)pkey));
      return i2d_ASN1_OBJECT(OBJ_nid2obj(nid), pder);
  }
  
  static int gost2001_param_encode(const EVP_PKEY *pkey, unsigned char **pder)
  {
      int nid =
          EC_GROUP_get_curve_name(EC_KEY_get0_group
                                  (EVP_PKEY_get0((EVP_PKEY *)pkey)));
      return i2d_ASN1_OBJECT(OBJ_nid2obj(nid), pder);
  }
  
  static int gost94_param_decode(EVP_PKEY *pkey, const unsigned char **pder,
                                 int derlen)
  {
      ASN1_OBJECT *obj = NULL;
      DSA *dsa = EVP_PKEY_get0(pkey);
      int nid;
      if (d2i_ASN1_OBJECT(&obj, pder, derlen) == NULL) {
          return 0;
      }
      nid = OBJ_obj2nid(obj);
      ASN1_OBJECT_free(obj);
      if (!dsa) {
          dsa = DSA_new();
          if (!EVP_PKEY_assign(pkey, NID_id_GostR3410_94, dsa))
              return 0;
      }
      if (!fill_GOST94_params(dsa, nid))
          return 0;
      return 1;
  }
  
  static int gost2001_param_decode(EVP_PKEY *pkey, const unsigned char **pder,
                                   int derlen)
  {
      ASN1_OBJECT *obj = NULL;
      int nid;
      EC_KEY *ec = EVP_PKEY_get0(pkey);
      if (d2i_ASN1_OBJECT(&obj, pder, derlen) == NULL) {
          return 0;
      }
      nid = OBJ_obj2nid(obj);
      ASN1_OBJECT_free(obj);
      if (!ec) {
          ec = EC_KEY_new();
          if (!EVP_PKEY_assign(pkey, NID_id_GostR3410_2001, ec))
              return 0;
      }
      if (!fill_GOST2001_params(ec, nid))
          return 0;
      return 1;
  }
  
  /* ----------------------------------------------------------------------*/
  int register_ameth_gost(int nid, EVP_PKEY_ASN1_METHOD **ameth,
                          const char *pemstr, const char *info)
  {
      *ameth = EVP_PKEY_asn1_new(nid, ASN1_PKEY_SIGPARAM_NULL, pemstr, info);
      if (!*ameth)
          return 0;
      switch (nid) {
      case NID_id_GostR3410_94:
          EVP_PKEY_asn1_set_free(*ameth, pkey_free_gost94);
          EVP_PKEY_asn1_set_private(*ameth,
                                    priv_decode_gost, priv_encode_gost,
                                    priv_print_gost94);
  
          EVP_PKEY_asn1_set_param(*ameth,
                                  gost94_param_decode, gost94_param_encode,
                                  param_missing_gost94, param_copy_gost94,
                                  param_cmp_gost94, param_print_gost94);
          EVP_PKEY_asn1_set_public(*ameth,
                                   pub_decode_gost94, pub_encode_gost94,
                                   pub_cmp_gost94, pub_print_gost94,
                                   pkey_size_gost, pkey_bits_gost);
  
          EVP_PKEY_asn1_set_ctrl(*ameth, pkey_ctrl_gost);
          break;
      case NID_id_GostR3410_2001:
          EVP_PKEY_asn1_set_free(*ameth, pkey_free_gost01);
          EVP_PKEY_asn1_set_private(*ameth,
                                    priv_decode_gost, priv_encode_gost,
                                    priv_print_gost01);
  
          EVP_PKEY_asn1_set_param(*ameth,
                                  gost2001_param_decode, gost2001_param_encode,
                                  param_missing_gost01, param_copy_gost01,
                                  param_cmp_gost01, param_print_gost01);
          EVP_PKEY_asn1_set_public(*ameth,
                                   pub_decode_gost01, pub_encode_gost01,
                                   pub_cmp_gost01, pub_print_gost01,
                                   pkey_size_gost, pkey_bits_gost);
  
          EVP_PKEY_asn1_set_ctrl(*ameth, pkey_ctrl_gost);
          break;
      case NID_id_Gost28147_89_MAC:
          EVP_PKEY_asn1_set_free(*ameth, mackey_free_gost);
          EVP_PKEY_asn1_set_ctrl(*ameth, mac_ctrl_gost);
          break;
      }
      return 1;
  }
  