OPENSSL_KEYTYPE_RSA
      (int)
     OPENSSL_KEYTYPE_DSA
      (int)
     OPENSSL_KEYTYPE_DH
      (int)
     OPENSSL_KEYTYPE_EC
      (int)
     OPENSSL_KEYTYPE_X25519
      (int)
     OPENSSL_KEYTYPE_ED25519
      (int)
     OPENSSL_KEYTYPE_X448
      (int)
     OPENSSL_KEYTYPE_ED448
      (int)
     