nym-client: using the new Sphinx max packet length constant

nym-client/src/sockets/tcp.rs

@@ -95,6 +95,16 @@ impl ClientRequest {
         mut input_tx: mpsc::UnboundedSender<InputMessage>,
     ) -> ServerResponse {
         trace!("sending to: {:?}, msg: {:?}", recipient_address, msg);
+        if msg.len() > sphinx::constants::MAXIMUM_PLAINTEXT_LENGTH {
+            return ServerResponse::Error {
+                message: format!(
+                    "too long message. Sent {} bytes while the maximum is {}",
+                    msg.len(),
+                    sphinx::constants::MAXIMUM_PLAINTEXT_LENGTH
+                )
+                .to_string(),
+            };
+        }
         let dummy_surb = [0; 16];
         let input_msg = InputMessage(Destination::new(recipient_address, dummy_surb), msg);
         input_tx.send(input_msg).await.unwrap();

nym-client/src/sockets/ws.rs

@@ -188,20 +188,12 @@ impl ClientRequest {
         mut input_tx: mpsc::UnboundedSender<InputMessage>,
     ) -> ServerResponse {
         let message_bytes = msg.into_bytes();
-        // TODO: wait until 0.4.0 release to replace those constants with newly exposed
-        // sphinx::constants::MAXIMUM_PLAINTEXT_LENGTH
-        // we can't do it now for compatibility reasons as most recent sphinx revision
-        // has breaking changes due to packet format changes
-        let maximum_plaintext_length = sphinx::constants::PAYLOAD_SIZE
-            - sphinx::constants::SECURITY_PARAMETER
-            - sphinx::constants::DESTINATION_ADDRESS_LENGTH
-            - 1;
-        if message_bytes.len() > maximum_plaintext_length {
+        if message_bytes.len() > sphinx::constants::MAXIMUM_PLAINTEXT_LENGTH {
             return ServerResponse::Error {
                 message: format!(
                     "too long message. Sent {} bytes while the maximum is {}",
                     message_bytes.len(),
-                    maximum_plaintext_length
+                    sphinx::constants::MAXIMUM_PLAINTEXT_LENGTH
                 )
                 .to_string(),
             };