don't set local address if not specified

libi2pd_client/ClientContext.cpp

@@ -691,7 +691,7 @@ namespace client
 					i2p::data::SigningKeyType sigType = section.second.get (I2P_SERVER_TUNNEL_SIGNATURE_TYPE, i2p::data::SIGNING_KEY_TYPE_EDDSA_SHA512_ED25519);
 					i2p::data::CryptoKeyType cryptoType = section.second.get (I2P_CLIENT_TUNNEL_CRYPTO_TYPE, i2p::data::CRYPTO_KEY_TYPE_ELGAMAL);
 
-					std::string address = section.second.get<std::string> (I2P_SERVER_TUNNEL_ADDRESS, "127.0.0.1");
+					std::string address = section.second.get<std::string> (I2P_SERVER_TUNNEL_ADDRESS, "");
 					bool isUniqueLocal = section.second.get(I2P_SERVER_TUNNEL_ENABLE_UNIQUE_LOCAL, true);
 
 					// I2CP
@@ -718,6 +718,7 @@ namespace client
 					{
 						// udp server tunnel
 						// TODO: hostnames
+						if (address.empty ()) address = "127.0.0.1";
 						auto localAddress = boost::asio::ip::address::from_string(address);
 						boost::asio::ip::udp::endpoint endpoint(boost::asio::ip::address::from_string(host), port);
 						auto serverTunnel = std::make_shared<I2PUDPServerTunnel>(name, localDestination, localAddress, endpoint, port, gzip);