Add more descriptive error when signing/decrypting using hw wallet.

rpc/src/v1/helpers/dispatch.rs

@@ -512,6 +512,10 @@ pub fn execute<D: Dispatcher + 'static>(
 				).boxed()
 		},
 		ConfirmationPayload::EthSignMessage(address, data) => {
+			if accounts.is_hardware_address(address) {
+				return future::err(errors::unsupported("Signing via hardware wallets is not supported.", None)).boxed();
+			}
+
 			let hash = eth_data_hash(data);
 			let res = signature(&accounts, address, hash, pass)
 				.map(|result| result
@@ -522,6 +526,10 @@ pub fn execute<D: Dispatcher + 'static>(
 			future::done(res).boxed()
 		},
 		ConfirmationPayload::Decrypt(address, data) => {
+			if accounts.is_hardware_address(address) {
+				return future::err(errors::unsupported("Decrypting via hardware wallets is not supported.", None)).boxed();
+			}
+
 			let res = decrypt(&accounts, address, data, pass)
 				.map(|result| result
 					.map(RpcBytes)

rpc/src/v1/helpers/errors.rs

@@ -71,6 +71,14 @@ pub fn public_unsupported(details: Option<String>) -> Error {
 	}
 }
 
+pub fn unsupported<T: Into<String>>(msg: T, details: Option<T>) -> Error {
+	Error {
+		code: ErrorCode::ServerError(codes::UNSUPPORTED_REQUEST),
+		message: msg.into(),
+		data: details.map(Into::into).map(Value::String),
+	}
+}
+
 pub fn request_not_found() -> Error {
 	Error {
 		code: ErrorCode::ServerError(codes::REQUEST_NOT_FOUND),