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 "internal/deprecated.h" /* to be able to use EC_KEY and EC_GROUP */
  11
  12 #include <openssl/err.h>
  13 #include "crypto/sm2err.h"
  14 #include "crypto/sm2.h"
  15 #include <openssl/ec.h> /* EC_KEY and EC_GROUP functions */
  16
  17 /*
  18  * SM2 key generation is implemented within ec_generate_key() in
  19  * crypto/ec/ec_key.c
  20  */
  21
  22 int sm2_key_private_check(const EC_KEY *eckey)
  23 {
  24     int ret = 0;
  25     BIGNUM *max = NULL;
  26     const EC_GROUP *group = NULL;
  27     const BIGNUM *priv_key = NULL, *order = NULL;
  28
  29     if (eckey == NULL
  30             || (group = EC_KEY_get0_group(eckey)) == NULL
  31             || (priv_key = EC_KEY_get0_private_key(eckey)) == NULL
  32             || (order = EC_GROUP_get0_order(group)) == NULL ) {
  33         ERR_raise(ERR_LIB_SM2, ERR_R_PASSED_NULL_PARAMETER);
  34         return 0;
  35     }
  36
  37     /* range of SM2 private key is [1, n-1) */
  38     max = BN_dup(order);
  39     if (max == NULL || !BN_sub_word(max, 1))
  40         goto end;
  41     if (BN_cmp(priv_key, BN_value_one()) < 0
  42         || BN_cmp(priv_key, max) >= 0) {
  43         ERR_raise(ERR_LIB_SM2, SM2_R_INVALID_PRIVATE_KEY);
  44         goto end;
  45     }
  46     ret = 1;
  47
  48  end:
  49     BN_free(max);
  50     return ret;
  51 }