[FOLD] Use unique_ptr to manage resources in rsa_generate_key

src/ripple/basics/impl/make_SSLContext.cpp

@@ -68,35 +68,40 @@ struct custom_delete <X509>
  }
 };
 
+template <>
+struct custom_delete <BIGNUM>
+{
+ void operator() (BIGNUM* bn) const
+ {
+ BN_free(bn);
+ }
+};
+
 template <class T>
 using custom_delete_unique_ptr = std::unique_ptr <T, custom_delete <T>>;
 
 // RSA
 
 using rsa_ptr = custom_delete_unique_ptr <RSA>;
+using bignum_ptr = custom_delete_unique_ptr<BIGNUM>;
 
 static rsa_ptr rsa_generate_key (int n_bits)
 {
 #if OPENSSL_VERSION_NUMBER >= 0x00908000L
- BIGNUM *bn = BN_new();
- BN_set_word(bn, RSA_F4);
-
- RSA* rsa = RSA_new();
- if (RSA_generate_key_ex(rsa, n_bits, bn, nullptr) != 1)
- {
- RSA_free(rsa);
- rsa = nullptr;
- }
+ bignum_ptr bn{BN_new()};
+ BN_set_word(bn.get(), RSA_F4);
 
- BN_free(bn);
+ rsa_ptr rsa{RSA_new()};
+ if (RSA_generate_key_ex(rsa.get(), n_bits, bn.get(), nullptr) != 1)
+ rsa.reset();
 #else
- RSA* rsa = RSA_generate_key (n_bits, RSA_F4, nullptr, nullptr);
+ rsa_ptr rsa{RSA_generate_key (n_bits, RSA_F4, nullptr, nullptr)};
 #endif
 
  if (rsa == nullptr)
  LogicError ("RSA_generate_key failed");
 
- return rsa_ptr (rsa);
+ return rsa;
 }
 
 // EVP_PKEY