Implement ErrorMessage msg and ErrorAction::SendErrorMessage + fuzz test

diff --git a/fuzz/Cargo.toml b/fuzz/Cargo.toml
index 53724f356418a3898f8d605a2f654d1a1a582699..14610540510f394fec670a92dadeb0f5ad17e3d8 100644 (file)
--- a/fuzz/Cargo.toml
+++ b/fuzz/Cargo.toml
@@ -114,3 +114,7 @@ path = "fuzz_targets/msg_targets/msg_update_fail_htlc_target.rs"
 [[bin]]
 name = "msg_channel_reestablish_target"
 path = "fuzz_targets/msg_targets/msg_channel_reestablish_target.rs"
+
+[[bin]]
+name = "msg_error_message_target"
+path = "fuzz_targets/msg_targets/msg_error_message_target.rs"

diff --git a/fuzz/fuzz_targets/channel_target.rs b/fuzz/fuzz_targets/channel_target.rs
index 23c63fee72bd0bb610e3d10acac798969a956889..fd23d9c2f876010d7287bfc1f08429c697f496d0 100644 (file)
--- a/fuzz/fuzz_targets/channel_target.rs
+++ b/fuzz/fuzz_targets/channel_target.rs
@@ -118,6 +118,7 @@ pub fn do_test(data: &[u8]) {
                                        msgs::DecodeError::UnknownRealmByte => return,
                                        msgs::DecodeError::BadPublicKey => return,
                                        msgs::DecodeError::BadSignature => return,
+                                       msgs::DecodeError::BadText => return,
                                        msgs::DecodeError::ExtraAddressesPerType => return,
                                        msgs::DecodeError::WrongLength => panic!("We picked the length..."),
                                }
@@ -138,6 +139,7 @@ pub fn do_test(data: &[u8]) {
                                                msgs::DecodeError::UnknownRealmByte => return,
                                                msgs::DecodeError::BadPublicKey => return,
                                                msgs::DecodeError::BadSignature => return,
+                                               msgs::DecodeError::BadText => return,
                                                msgs::DecodeError::ExtraAddressesPerType => return,
                                                msgs::DecodeError::WrongLength => panic!("We picked the length..."),
                                        }

diff --git a/fuzz/fuzz_targets/msg_targets/gen_target.sh b/fuzz/fuzz_targets/msg_targets/gen_target.sh
index 4a5dc2fc5565d9c25739c97b01faf512c5f74e72..37eac67a720e8304c0db54859ccd49651807a292 100755 (executable)
--- a/fuzz/fuzz_targets/msg_targets/gen_target.sh
+++ b/fuzz/fuzz_targets/msg_targets/gen_target.sh
@@ -1,4 +1,4 @@
-for target in CommitmentSigned FundingCreated FundingLocked FundingSigned OpenChannel RevokeAndACK Shutdown UpdateAddHTLC UpdateFailHTLC UpdateFailMalformedHTLC UpdateFee UpdateFulfillHTLC AcceptChannel ClosingSigned ChannelReestablish; do
+for target in CommitmentSigned FundingCreated FundingLocked FundingSigned OpenChannel RevokeAndACK Shutdown UpdateAddHTLC UpdateFailHTLC UpdateFailMalformedHTLC UpdateFee UpdateFulfillHTLC AcceptChannel ClosingSigned ChannelReestablish ErrorMessage; do
        tn=$(echo $target | sed 's/\([a-z0-9]\)\([A-Z]\)/\1_\2/g')
        fn=msg_$(echo $tn | tr '[:upper:]' '[:lower:]')_target.rs
        cat msg_target_template.txt | sed s/MSG_TARGET/$target/ > $fn

diff --git a/fuzz/fuzz_targets/msg_targets/msg_error_message_target.rs b/fuzz/fuzz_targets/msg_targets/msg_error_message_target.rs
new file mode 100644 (file)
index 0000000..7022786
--- /dev/null
+++ b/fuzz/fuzz_targets/msg_targets/msg_error_message_target.rs
@@ -0,0 +1,48 @@
+// This file is auto-generated by gen_target.sh based on msg_target_template.txt
+// To modify it, modify msg_target_template.txt and run gen_target.sh instead.
+
+extern crate lightning;
+
+use lightning::ln::msgs;
+use lightning::util::reset_rng_state;
+
+use lightning::ln::msgs::{MsgEncodable, MsgDecodable};
+
+mod utils;
+
+#[inline]
+pub fn do_test(data: &[u8]) {
+       reset_rng_state();
+       test_msg!(msgs::ErrorMessage, data);
+}
+
+#[cfg(feature = "afl")]
+extern crate afl;
+#[cfg(feature = "afl")]
+fn main() {
+       afl::read_stdio_bytes(|data| {
+               do_test(&data);
+       });
+}
+
+#[cfg(feature = "honggfuzz")]
+#[macro_use] extern crate honggfuzz;
+#[cfg(feature = "honggfuzz")]
+fn main() {
+       loop {
+               fuzz!(|data| {
+                       do_test(data);
+               });
+       }
+}
+
+#[cfg(test)]
+mod tests {
+       use utils::extend_vec_from_hex;
+       #[test]
+       fn duplicate_crash() {
+               let mut a = Vec::new();
+               extend_vec_from_hex("00", &mut a);
+               super::do_test(&a);
+       }
+}

diff --git a/src/ln/msgs.rs b/src/ln/msgs.rs
index 1bc6f0ba63efcc57cfb1b8a0c9b8b0ee03eb40ac..e52a6d80bbd23f4eb809591f1b9eed08f7a27a11 100644 (file)
--- a/src/ln/msgs.rs
+++ b/src/ln/msgs.rs
@@ -31,6 +31,8 @@ pub enum DecodeError {
        BadPublicKey,
        /// Failed to decode a signature (ie it's invalid)
        BadSignature,
+       /// Value expected to be text wasn't decodable as text
+       BadText,
        /// Buffer not of right length (either too short or too long)
        WrongLength,
        /// node_announcement included more than one address of a given type!
@@ -138,6 +140,11 @@ pub struct Init {
        pub local_features: LocalFeatures,
 }
 
+pub struct ErrorMessage {
+       pub channel_id: [u8; 32],
+       pub data: String,
+}
+
 pub struct Ping {
        pub ponglen: u16,
        pub byteslen: u16,
@@ -375,6 +382,10 @@ pub enum ErrorAction {
        DisconnectPeer,
        /// The peer did something harmless that we weren't able to process, just log and ignore
        IgnoreError,
+       /// The peer did something incorrect. Tell them.
+       SendErrorMessage {
+               msg: ErrorMessage
+       },
 }
 
 pub struct HandleError { //TODO: rename me
@@ -486,6 +497,7 @@ impl Error for DecodeError {
                        DecodeError::UnknownRealmByte => "Unknown realm byte in Onion packet",
                        DecodeError::BadPublicKey => "Invalid public key in packet",
                        DecodeError::BadSignature => "Invalid signature in packet",
+                       DecodeError::BadText => "Invalid text in packet",
                        DecodeError::WrongLength => "Data was wrong length for packet",
                        DecodeError::ExtraAddressesPerType => "More than one address of a single type",
                }
@@ -1600,6 +1612,37 @@ impl MsgEncodable for OnionErrorPacket {
        }
 }
 
+impl MsgEncodable for ErrorMessage {
+       fn encode(&self) -> Vec<u8> {
+               let mut res = Vec::with_capacity(34 + self.data.len());
+               res.extend_from_slice(&self.channel_id);
+               res.extend_from_slice(&byte_utils::be16_to_array(self.data.len() as u16));
+               res.extend_from_slice(&self.data.as_bytes());
+               res
+       }
+}
+impl MsgDecodable for ErrorMessage {
+       fn decode(v: &[u8]) -> Result<Self,DecodeError> {
+               if v.len() < 34 {
+                       return Err(DecodeError::WrongLength);
+               }
+               let len = byte_utils::slice_to_be16(&v[32..34]);
+               if v.len() < 34 + len as usize {
+                       return Err(DecodeError::WrongLength);
+               }
+               let data = match String::from_utf8(v[34..34 + len as usize].to_vec()) {
+                       Ok(s) => s,
+                       Err(_) => return Err(DecodeError::BadText),
+               };
+               let mut channel_id = [0; 32];
+               channel_id[..].copy_from_slice(&v[0..32]);
+               Ok(Self {
+                       channel_id,
+                       data,
+               })
+       }
+}
+
 #[cfg(test)]
 mod tests {
        use bitcoin::util::misc::hex_bytes;

diff --git a/src/ln/peer_handler.rs b/src/ln/peer_handler.rs
index 754d457f7bfd778bf0c03c98b4d8dfb0aed09021..6c20316ed9ba5427bde7886999c2f4b526c750d5 100644 (file)
--- a/src/ln/peer_handler.rs
+++ b/src/ln/peer_handler.rs
@@ -302,6 +302,10 @@ impl<Descriptor: SocketDescriptor> PeerManager<Descriptor> {
                                                                                                        msgs::ErrorAction::IgnoreError => {
                                                                                                                continue;
                                                                                                        },
+                                                                                                       msgs::ErrorAction::SendErrorMessage { msg } => {
+                                                                                                               encode_and_send_msg!(msg, 17);
+                                                                                                               continue;
+                                                                                                       },
                                                                                                }
                                                                                        } else {
                                                                                                return Err(PeerHandleError{ no_connection_possible: false });