crypto/sm2/sm2_key.c

   1 /*
   2  * Copyright 2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <openssl/err.h>
  11 #include "crypto/sm2err.h"
  12 #include "crypto/sm2.h"
  13 #include <openssl/ec.h> /* EC_KEY and EC_GROUP functions */
  14
  15 /*
  16  * SM2 key generation is implemented within ec_generate_key() in
  17  * crypto/ec/ec_key.c
  18  */
  19
  20 int sm2_key_private_check(const EC_KEY *eckey)
  21 {
  22     int ret = 0;
  23     BIGNUM *max = NULL;
  24     const EC_GROUP *group = NULL;
  25     const BIGNUM *priv_key = NULL, *order = NULL;
  26
  27     if (eckey == NULL
  28             || (group = EC_KEY_get0_group(eckey)) == NULL
  29             || (priv_key = EC_KEY_get0_private_key(eckey)) == NULL
  30             || (order = EC_GROUP_get0_order(group)) == NULL ) {
  31         ERR_raise(ERR_LIB_SM2, ERR_R_PASSED_NULL_PARAMETER);
  32         return 0;
  33     }
  34
  35     /* range of SM2 private key is [1, n-1) */
  36     max = BN_dup(order);
  37     if (max == NULL || !BN_sub_word(max, 1))
  38         goto end;
  39     if (BN_cmp(priv_key, BN_value_one()) < 0
  40         || BN_cmp(priv_key, max) >= 0) {
  41         ERR_raise(ERR_LIB_SM2, SM2_R_INVALID_PRIVATE_KEY);
  42         goto end;
  43     }
  44     ret = 1;
  45
  46  end:
  47     BN_free(max);
  48     return ret;
  49 }