crypto/dsa/dsa_backend.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/core_names.h>
  11 #include "crypto/dsa.h"
  12
  13 /*
  14  * The intention with the "backend" source file is to offer backend support
  15  * for legacy backends (EVP_PKEY_ASN1_METHOD and EVP_PKEY_METHOD) and provider
  16  * implementations alike.
  17  */
  18
  19 int dsa_key_fromdata(DSA *dsa, const OSSL_PARAM params[])
  20 {
  21     const OSSL_PARAM *param_priv_key, *param_pub_key;
  22     BIGNUM *priv_key = NULL, *pub_key = NULL;
  23
  24     if (dsa == NULL)
  25         return 0;
  26
  27     param_priv_key =
  28         OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PRIV_KEY);
  29     param_pub_key =
  30         OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_PUB_KEY);
  31
  32     /* It's ok if neither half is present */
  33     if (param_priv_key == NULL && param_pub_key == NULL)
  34         return 1;
  35
  36     /*
  37      * DH documentation says that a public key must be present if a
  38      * private key is present.
  39      */
  40     if (param_priv_key != NULL && param_pub_key == NULL)
  41         return 0;
  42
  43     if (param_pub_key != NULL && !OSSL_PARAM_get_BN(param_pub_key, &pub_key))
  44         goto err;
  45     if (param_priv_key != NULL && !OSSL_PARAM_get_BN(param_priv_key, &priv_key))
  46         goto err;
  47
  48     if (!DSA_set0_key(dsa, pub_key, priv_key))
  49         goto err;
  50
  51     return 1;
  52
  53  err:
  54     BN_clear_free(priv_key);
  55     BN_free(pub_key);
  56     return 0;
  57 }