Add a new `WarningMessage` message to send and receive warnings

[rust-lightning] / lightning / src / ln / msgs.rs

diff --git a/lightning/src/ln/msgs.rs b/lightning/src/ln/msgs.rs
index 39c00105f8d675e5cf5ce664b2d7416654c40cfb..1335a04c47a1c4f0e957cee9ce9a094acfcd244e 100644 (file)
--- a/lightning/src/ln/msgs.rs
+++ b/lightning/src/ln/msgs.rs
@@ -80,12 +80,29 @@ pub struct Init {
 /// An error message to be sent or received from a peer
 #[derive(Clone, Debug, PartialEq)]
 pub struct ErrorMessage {
-       /// The channel ID involved in the error
+       /// The channel ID involved in the error.
+       ///
+       /// All-0s indicates a general error unrelated to a specific channel, after which all channels
+       /// with the sending peer should be closed.
        pub channel_id: [u8; 32],
        /// A possibly human-readable error description.
-       /// The string should be sanitized before it is used (e.g. emitted to logs
-       /// or printed to stdout).  Otherwise, a well crafted error message may trigger a security
-       /// vulnerability in the terminal emulator or the logging subsystem.
+       /// The string should be sanitized before it is used (e.g. emitted to logs or printed to
+       /// stdout). Otherwise, a well crafted error message may trigger a security vulnerability in
+       /// the terminal emulator or the logging subsystem.
+       pub data: String,
+}
+
+/// A warning message to be sent or received from a peer
+#[derive(Clone, Debug, PartialEq)]
+pub struct WarningMessage {
+       /// The channel ID involved in the warning.
+       ///
+       /// All-0s indicates a warning unrelated to a specific channel.
+       pub channel_id: [u8; 32],
+       /// A possibly human-readable warning description.
+       /// The string should be sanitized before it is used (e.g. emitted to logs or printed to
+       /// stdout). Otherwise, a well crafted error message may trigger a security vulnerability in
+       /// the terminal emulator or the logging subsystem.
        pub data: String,
 }
 
@@ -1515,6 +1532,32 @@ impl Readable for ErrorMessage {
        }
 }
 
+impl Writeable for WarningMessage {
+       fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+               self.channel_id.write(w)?;
+               (self.data.len() as u16).write(w)?;
+               w.write_all(self.data.as_bytes())?;
+               Ok(())
+       }
+}
+
+impl Readable for WarningMessage {
+       fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+               Ok(Self {
+                       channel_id: Readable::read(r)?,
+                       data: {
+                               let mut sz: usize = <u16 as Readable>::read(r)? as usize;
+                               let data = read_to_end(r)?;
+                               sz = cmp::min(data.len(), sz);
+                               match String::from_utf8(data[..sz as usize].to_vec()) {
+                                       Ok(s) => s,
+                                       Err(_) => return Err(DecodeError::InvalidValue),
+                               }
+                       }
+               })
+       }
+}
+
 impl Writeable for UnsignedNodeAnnouncement {
        fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
                self.features.write(w)?;
@@ -2405,6 +2448,17 @@ mod tests {
                assert_eq!(encoded_value, target_value);
        }
 
+       #[test]
+       fn encoding_warning() {
+               let error = msgs::WarningMessage {
+                       channel_id: [2; 32],
+                       data: String::from("rust-lightning"),
+               };
+               let encoded_value = error.encode();
+               let target_value = hex::decode("0202020202020202020202020202020202020202020202020202020202020202000e727573742d6c696768746e696e67").unwrap();
+               assert_eq!(encoded_value, target_value);
+       }
+
        #[test]
        fn encoding_ping() {
                let ping = msgs::Ping {