diff --git a/lightning/src/onion_message/functional_tests.rs b/lightning/src/onion_message/functional_tests.rs index 029038a9fe7..0c3c67d4483 100644 --- a/lightning/src/onion_message/functional_tests.rs +++ b/lightning/src/onion_message/functional_tests.rs @@ -19,7 +19,7 @@ use crate::routing::test_utils::{add_channel, add_or_update_node}; use crate::sign::{NodeSigner, Recipient}; use crate::util::ser::{FixedLengthReader, LengthReadable, Writeable, Writer}; use crate::util::test_utils; -use super::messenger::{CustomOnionMessageHandler, DefaultMessageRouter, Destination, OnionMessagePath, OnionMessenger, PendingOnionMessage, Responder, ResponseInstruction, SendError}; +use super::messenger::{CustomOnionMessageHandler, DefaultMessageRouter, Destination, OnionMessagePath, OnionMessenger, PendingOnionMessage, Responder, ResponseInstruction, SendError, SendSuccess}; use super::offers::{OffersMessage, OffersMessageHandler}; use super::packet::{OnionMessageContents, Packet}; @@ -81,20 +81,20 @@ impl OffersMessageHandler for TestOffersMessageHandler { #[derive(Clone, Debug, PartialEq)] enum TestCustomMessage { - Request, - Response, + Ping, + Pong, } -const CUSTOM_REQUEST_MESSAGE_TYPE: u64 = 4242; -const CUSTOM_RESPONSE_MESSAGE_TYPE: u64 = 4343; -const CUSTOM_REQUEST_MESSAGE_CONTENTS: [u8; 32] = [42; 32]; -const CUSTOM_RESPONSE_MESSAGE_CONTENTS: [u8; 32] = [43; 32]; +const CUSTOM_PING_MESSAGE_TYPE: u64 = 4242; +const CUSTOM_PONG_MESSAGE_TYPE: u64 = 4343; +const CUSTOM_PING_MESSAGE_CONTENTS: [u8; 32] = [42; 32]; +const CUSTOM_PONG_MESSAGE_CONTENTS: [u8; 32] = [43; 32]; impl OnionMessageContents for TestCustomMessage { fn tlv_type(&self) -> u64 { match self { - TestCustomMessage::Request => CUSTOM_REQUEST_MESSAGE_TYPE, - TestCustomMessage::Response => CUSTOM_RESPONSE_MESSAGE_TYPE, + TestCustomMessage::Ping => CUSTOM_PING_MESSAGE_TYPE, + TestCustomMessage::Pong => CUSTOM_PONG_MESSAGE_TYPE, } } fn msg_type(&self) -> &'static str { @@ -105,23 +105,46 @@ impl OnionMessageContents for TestCustomMessage { impl Writeable for TestCustomMessage { fn write(&self, w: &mut W) -> Result<(), io::Error> { match self { - TestCustomMessage::Request => Ok(CUSTOM_REQUEST_MESSAGE_CONTENTS.write(w)?), - TestCustomMessage::Response => Ok(CUSTOM_RESPONSE_MESSAGE_CONTENTS.write(w)?), + TestCustomMessage::Ping => Ok(CUSTOM_PING_MESSAGE_CONTENTS.write(w)?), + TestCustomMessage::Pong => Ok(CUSTOM_PONG_MESSAGE_CONTENTS.write(w)?), } } } struct TestCustomMessageHandler { - expected_messages: Mutex>, + expectations: Mutex>, +} + +struct OnHandleCustomMessage { + expect: TestCustomMessage, + include_reply_path: bool, } impl TestCustomMessageHandler { fn new() -> Self { - Self { expected_messages: Mutex::new(VecDeque::new()) } + Self { expectations: Mutex::new(VecDeque::new()) } } fn expect_message(&self, message: TestCustomMessage) { - self.expected_messages.lock().unwrap().push_back(message); + self.expectations.lock().unwrap().push_back( + OnHandleCustomMessage { + expect: message, + include_reply_path: false, + } + ); + } + + fn expect_message_and_response(&self, message: TestCustomMessage) { + self.expectations.lock().unwrap().push_back( + OnHandleCustomMessage { + expect: message, + include_reply_path: true, + } + ); + } + + fn get_next_expectation(&self) -> OnHandleCustomMessage { + self.expectations.lock().unwrap().pop_front().expect("No expectations remaining") } } @@ -132,38 +155,45 @@ impl Drop for TestCustomMessageHandler { return; } } - assert!(self.expected_messages.lock().unwrap().is_empty()); + assert!(self.expectations.lock().unwrap().is_empty()); } } impl CustomOnionMessageHandler for TestCustomMessageHandler { type CustomMessage = TestCustomMessage; fn handle_custom_message(&self, msg: Self::CustomMessage, responder: Option) -> ResponseInstruction { - match self.expected_messages.lock().unwrap().pop_front() { - Some(expected_msg) => assert_eq!(expected_msg, msg), - None => panic!("Unexpected message: {:?}", msg), - } - let response_option = match msg { - TestCustomMessage::Request => Some(TestCustomMessage::Response), - TestCustomMessage::Response => None, + let expectation = self.get_next_expectation(); + assert_eq!(msg, expectation.expect); + + let response = match msg { + TestCustomMessage::Ping => TestCustomMessage::Pong, + TestCustomMessage::Pong => TestCustomMessage::Ping, }; - if let (Some(response), Some(responder)) = (response_option, responder) { - responder.respond(response) - } else { - ResponseInstruction::NoResponse + + // Sanity check: expecting to include reply path when responder is absent should panic. + if expectation.include_reply_path && responder.is_none() { + panic!("Expected to include a reply_path, but the responder was absent.") + } + + match responder { + Some(responder) if expectation.include_reply_path => { + responder.respond_with_reply_path(response) + }, + Some(responder) => responder.respond(response), + None => ResponseInstruction::NoResponse, } } fn read_custom_message(&self, message_type: u64, buffer: &mut R) -> Result, DecodeError> where Self: Sized { match message_type { - CUSTOM_REQUEST_MESSAGE_TYPE => { + CUSTOM_PING_MESSAGE_TYPE => { let buf = read_to_end(buffer)?; - assert_eq!(buf, CUSTOM_REQUEST_MESSAGE_CONTENTS); - Ok(Some(TestCustomMessage::Request)) + assert_eq!(buf, CUSTOM_PING_MESSAGE_CONTENTS); + Ok(Some(TestCustomMessage::Ping)) }, - CUSTOM_RESPONSE_MESSAGE_TYPE => { + CUSTOM_PONG_MESSAGE_TYPE => { let buf = read_to_end(buffer)?; - assert_eq!(buf, CUSTOM_RESPONSE_MESSAGE_CONTENTS); - Ok(Some(TestCustomMessage::Response)) + assert_eq!(buf, CUSTOM_PONG_MESSAGE_CONTENTS); + Ok(Some(TestCustomMessage::Pong)) }, _ => Ok(None), } @@ -298,18 +328,18 @@ fn pass_along_path(path: &Vec) { #[test] fn one_unblinded_hop() { let nodes = create_nodes(2); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let destination = Destination::Node(nodes[1].node_id); nodes[0].messenger.send_onion_message(test_msg, destination, None).unwrap(); - nodes[1].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[1].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&nodes); } #[test] fn two_unblinded_hops() { let nodes = create_nodes(3); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let path = OnionMessagePath { intermediate_nodes: vec![nodes[1].node_id], @@ -318,27 +348,27 @@ fn two_unblinded_hops() { }; nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap(); - nodes[2].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[2].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&nodes); } #[test] fn one_blinded_hop() { let nodes = create_nodes(2); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let secp_ctx = Secp256k1::new(); let blinded_path = BlindedPath::new_for_message(&[], nodes[1].node_id, &*nodes[1].entropy_source, &secp_ctx).unwrap(); let destination = Destination::BlindedPath(blinded_path); nodes[0].messenger.send_onion_message(test_msg, destination, None).unwrap(); - nodes[1].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[1].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&nodes); } #[test] fn two_unblinded_two_blinded() { let nodes = create_nodes(5); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let secp_ctx = Secp256k1::new(); let intermediate_nodes = [ForwardNode { node_id: nodes[3].node_id, short_channel_id: None }]; @@ -350,14 +380,14 @@ fn two_unblinded_two_blinded() { }; nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap(); - nodes[4].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[4].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&nodes); } #[test] fn three_blinded_hops() { let nodes = create_nodes(4); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let secp_ctx = Secp256k1::new(); let intermediate_nodes = [ @@ -368,15 +398,117 @@ fn three_blinded_hops() { let destination = Destination::BlindedPath(blinded_path); nodes[0].messenger.send_onion_message(test_msg, destination, None).unwrap(); - nodes[3].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[3].custom_message_handler.expect_message(TestCustomMessage::Pong); + pass_along_path(&nodes); +} + +#[test] +fn async_response_over_one_blinded_hop() { + // Simulate an asynchronous interaction between two nodes, Alice and Bob. + + // 1. Set up the network with two nodes: Alice and Bob. + let nodes = create_nodes(2); + let alice = &nodes[0]; + let bob = &nodes[1]; + + // 2. Define the message sent from Bob to Alice. + let message = TestCustomMessage::Ping; + let path_id = Some([2; 32]); + + // 3. Simulate the creation of a Blinded Reply path provided by Bob. + let secp_ctx = Secp256k1::new(); + let reply_path = BlindedPath::new_for_message(&[], nodes[1].node_id, &*nodes[1].entropy_source, &secp_ctx).unwrap(); + + // 4. Create a responder using the reply path for Alice. + let responder = Some(Responder::new(reply_path, path_id)); + + // 5. Expect Alice to receive the message and create a response instruction for it. + alice.custom_message_handler.expect_message(message.clone()); + let response_instruction = nodes[0].custom_message_handler.handle_custom_message(message, responder); + + // 6. Simulate Alice asynchronously responding back to Bob with a response. + assert_eq!( + nodes[0].messenger.handle_onion_message_response(response_instruction), + Ok(Some(SendSuccess::Buffered)), + ); + + bob.custom_message_handler.expect_message(TestCustomMessage::Pong); + + pass_along_path(&nodes); +} + +#[test] +fn async_response_with_reply_path_succeeds() { + // Simulate an asynchronous interaction between two nodes, Alice and Bob. + // Create a channel between the two nodes to establish them as announced nodes, + // which allows the creation of the reply_path for successful communication. + + let mut nodes = create_nodes(2); + let alice = &nodes[0]; + let bob = &nodes[1]; + let secp_ctx = Secp256k1::new(); + + add_channel_to_graph(alice, bob, &secp_ctx, 24); + + // Alice receives a message from Bob with an added reply_path for responding back. + let message = TestCustomMessage::Ping; + let path_id = Some([2; 32]); + let reply_path = BlindedPath::new_for_message(&[], bob.node_id, &*bob.entropy_source, &secp_ctx).unwrap(); + + // Alice asynchronously responds to Bob, expecting a response back from him. + let responder = Responder::new(reply_path, path_id); + alice.custom_message_handler.expect_message_and_response(message.clone()); + let response_instruction = alice.custom_message_handler.handle_custom_message(message, Some(responder)); + + assert_eq!( + alice.messenger.handle_onion_message_response(response_instruction), + Ok(Some(SendSuccess::Buffered)), + ); + + // Set Bob's expectation and pass the Onion Message along the path. + bob.custom_message_handler.expect_message(TestCustomMessage::Pong); + pass_along_path(&nodes); + + // Bob responds back to Alice using the reply_path she included with the OnionMessage. + // Set Alice's expectation and reverse the path for the response. + alice.custom_message_handler.expect_message(TestCustomMessage::Ping); + nodes.reverse(); pass_along_path(&nodes); } +#[test] +fn async_response_with_reply_path_fails() { + // Simulate an asynchronous interaction between two unannounced nodes, Alice and Bob. + // Since the nodes are unannounced, attempting to respond using a reply_path + // will fail, leading to an expected failure in communication. + + let nodes = create_nodes(2); + let alice = &nodes[0]; + let bob = &nodes[1]; + let secp_ctx = Secp256k1::new(); + + // Alice receives a message from Bob with an added reply_path for responding back. + let message = TestCustomMessage::Ping; + let path_id = Some([2; 32]); + let reply_path = BlindedPath::new_for_message(&[], bob.node_id, &*bob.entropy_source, &secp_ctx).unwrap(); + + // Alice tries to asynchronously respond to Bob, but fails because the nodes are unannounced. + // Therefore, the reply_path cannot be used for the response. + let responder = Responder::new(reply_path, path_id); + alice.custom_message_handler.expect_message_and_response(message.clone()); + let response_instruction = alice.custom_message_handler.handle_custom_message(message, Some(responder)); + + assert_eq!( + alice.messenger.handle_onion_message_response(response_instruction), + Err(SendError::PathNotFound), + ); +} + #[test] fn too_big_packet_error() { // Make sure we error as expected if a packet is too big to send. let nodes = create_nodes(2); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let hop_node_id = nodes[1].node_id; let hops = vec![hop_node_id; 400]; @@ -394,7 +526,7 @@ fn we_are_intro_node() { // If we are sending straight to a blinded path and we are the introduction node, we need to // advance the blinded path by 1 hop so the second hop is the new introduction node. let mut nodes = create_nodes(3); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let secp_ctx = Secp256k1::new(); let intermediate_nodes = [ @@ -405,7 +537,7 @@ fn we_are_intro_node() { let destination = Destination::BlindedPath(blinded_path); nodes[0].messenger.send_onion_message(test_msg.clone(), destination, None).unwrap(); - nodes[2].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[2].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&nodes); // Try with a two-hop blinded path where we are the introduction node. @@ -413,7 +545,7 @@ fn we_are_intro_node() { let blinded_path = BlindedPath::new_for_message(&intermediate_nodes, nodes[1].node_id, &*nodes[1].entropy_source, &secp_ctx).unwrap(); let destination = Destination::BlindedPath(blinded_path); nodes[0].messenger.send_onion_message(test_msg, destination, None).unwrap(); - nodes[1].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[1].custom_message_handler.expect_message(TestCustomMessage::Pong); nodes.remove(2); pass_along_path(&nodes); } @@ -422,7 +554,7 @@ fn we_are_intro_node() { fn invalid_blinded_path_error() { // Make sure we error as expected if a provided blinded path has 0 hops. let nodes = create_nodes(3); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let secp_ctx = Secp256k1::new(); let intermediate_nodes = [ForwardNode { node_id: nodes[1].node_id, short_channel_id: None }]; @@ -436,7 +568,7 @@ fn invalid_blinded_path_error() { #[test] fn reply_path() { let mut nodes = create_nodes(4); - let test_msg = TestCustomMessage::Request; + let test_msg = TestCustomMessage::Ping; let secp_ctx = Secp256k1::new(); // Destination::Node @@ -451,10 +583,10 @@ fn reply_path() { ]; let reply_path = BlindedPath::new_for_message(&intermediate_nodes, nodes[0].node_id, &*nodes[0].entropy_source, &secp_ctx).unwrap(); nodes[0].messenger.send_onion_message_using_path(path, test_msg.clone(), Some(reply_path)).unwrap(); - nodes[3].custom_message_handler.expect_message(TestCustomMessage::Request); + nodes[3].custom_message_handler.expect_message(TestCustomMessage::Ping); pass_along_path(&nodes); // Make sure the last node successfully decoded the reply path. - nodes[0].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[0].custom_message_handler.expect_message(TestCustomMessage::Pong); nodes.reverse(); pass_along_path(&nodes); @@ -472,11 +604,11 @@ fn reply_path() { let reply_path = BlindedPath::new_for_message(&intermediate_nodes, nodes[0].node_id, &*nodes[0].entropy_source, &secp_ctx).unwrap(); nodes[0].messenger.send_onion_message(test_msg, destination, Some(reply_path)).unwrap(); - nodes[3].custom_message_handler.expect_message(TestCustomMessage::Request); + nodes[3].custom_message_handler.expect_message(TestCustomMessage::Ping); pass_along_path(&nodes); // Make sure the last node successfully decoded the reply path. - nodes[0].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[0].custom_message_handler.expect_message(TestCustomMessage::Pong); nodes.reverse(); pass_along_path(&nodes); } @@ -510,7 +642,7 @@ fn invalid_custom_message_type() { #[test] fn peer_buffer_full() { let nodes = create_nodes(2); - let test_msg = TestCustomMessage::Request; + let test_msg = TestCustomMessage::Ping; let destination = Destination::Node(nodes[1].node_id); for _ in 0..188 { // Based on MAX_PER_PEER_BUFFER_SIZE in OnionMessenger nodes[0].messenger.send_onion_message(test_msg.clone(), destination.clone(), None).unwrap(); @@ -525,7 +657,7 @@ fn many_hops() { // of size [`crate::onion_message::packet::BIG_PACKET_HOP_DATA_LEN`]. let num_nodes: usize = 25; let nodes = create_nodes(num_nodes as u8); - let test_msg = TestCustomMessage::Response; + let test_msg = TestCustomMessage::Pong; let mut intermediate_nodes = vec![]; for i in 1..(num_nodes-1) { @@ -538,14 +670,14 @@ fn many_hops() { first_node_addresses: None, }; nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap(); - nodes[num_nodes-1].custom_message_handler.expect_message(TestCustomMessage::Response); + nodes[num_nodes-1].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&nodes); } #[test] fn requests_peer_connection_for_buffered_messages() { let nodes = create_nodes(3); - let message = TestCustomMessage::Request; + let message = TestCustomMessage::Ping; let secp_ctx = Secp256k1::new(); add_channel_to_graph(&nodes[0], &nodes[1], &secp_ctx, 42); @@ -583,7 +715,7 @@ fn requests_peer_connection_for_buffered_messages() { #[test] fn drops_buffered_messages_waiting_for_peer_connection() { let nodes = create_nodes(3); - let message = TestCustomMessage::Request; + let message = TestCustomMessage::Ping; let secp_ctx = Secp256k1::new(); add_channel_to_graph(&nodes[0], &nodes[1], &secp_ctx, 42); @@ -635,7 +767,7 @@ fn intercept_offline_peer_oms() { } } - let message = TestCustomMessage::Response; + let message = TestCustomMessage::Pong; let secp_ctx = Secp256k1::new(); let intermediate_nodes = [ForwardNode { node_id: nodes[1].node_id, short_channel_id: None }]; let blinded_path = BlindedPath::new_for_message( @@ -675,7 +807,7 @@ fn intercept_offline_peer_oms() { } nodes[1].messenger.forward_onion_message(onion_message, &final_node_vec[0].node_id).unwrap(); - final_node_vec[0].custom_message_handler.expect_message(TestCustomMessage::Response); + final_node_vec[0].custom_message_handler.expect_message(TestCustomMessage::Pong); pass_along_path(&vec![nodes.remove(1), final_node_vec.remove(0)]); } diff --git a/lightning/src/onion_message/messenger.rs b/lightning/src/onion_message/messenger.rs index fc3eead1e4f..aa5f6589492 100644 --- a/lightning/src/onion_message/messenger.rs +++ b/lightning/src/onion_message/messenger.rs @@ -264,14 +264,16 @@ pub struct Responder { impl Responder { /// Creates a new [`Responder`] instance with the provided reply path. - fn new(reply_path: BlindedPath, path_id: Option<[u8; 32]>) -> Self { + pub(super) fn new(reply_path: BlindedPath, path_id: Option<[u8; 32]>) -> Self { Responder { reply_path, path_id, } } - /// Creates the appropriate [`ResponseInstruction`] for a given response. + /// Creates a [`ResponseInstruction::WithoutReplyPath`] for a given response. + /// + /// Use when the recipient doesn't need to send back a reply to us. pub fn respond(self, response: T) -> ResponseInstruction { ResponseInstruction::WithoutReplyPath(OnionMessageResponse { message: response, @@ -279,6 +281,17 @@ impl Responder { path_id: self.path_id, }) } + + /// Creates a [`ResponseInstruction::WithReplyPath`] for a given response. + /// + /// Use when the recipient needs to send back a reply to us. + pub fn respond_with_reply_path(self, response: T) -> ResponseInstruction { + ResponseInstruction::WithReplyPath(OnionMessageResponse { + message: response, + reply_path: self.reply_path, + path_id: self.path_id, + }) + } } /// This struct contains the information needed to reply to a received message. @@ -290,6 +303,9 @@ pub struct OnionMessageResponse { /// `ResponseInstruction` represents instructions for responding to received messages. pub enum ResponseInstruction { + /// Indicates that a response should be sent including a reply path for + /// the recipient to respond back. + WithReplyPath(OnionMessageResponse), /// Indicates that a response should be sent without including a reply path /// for the recipient to respond back. WithoutReplyPath(OnionMessageResponse), @@ -564,7 +580,11 @@ pub enum SendError { TooFewBlindedHops, /// The first hop is not a peer and doesn't have a known [`SocketAddress`]. InvalidFirstHop(PublicKey), - /// A path from the sender to the destination could not be found by the [`MessageRouter`]. + /// Indicates that a path could not be found by the [`MessageRouter`]. + /// + /// This occurs when either: + /// - No path from the sender to the destination was found to send the onion message + /// - No reply path to the sender could be created when responding to an onion message PathNotFound, /// Onion message contents must have a TLV type >= 64. InvalidMessage, @@ -981,6 +1001,27 @@ where .map_err(|_| SendError::PathNotFound) } + fn create_blinded_path(&self) -> Result { + let recipient = self.node_signer + .get_node_id(Recipient::Node) + .map_err(|_| SendError::GetNodeIdFailed)?; + let secp_ctx = &self.secp_ctx; + + let peers = self.message_recipients.lock().unwrap() + .iter() + .filter(|(_, peer)| matches!(peer, OnionMessageRecipient::ConnectedPeer(_))) + .map(|(node_id, _ )| ForwardNode { + node_id: *node_id, + short_channel_id: None, + }) + .collect::>(); + + self.message_router + .create_blinded_paths(recipient, peers, secp_ctx) + .and_then(|paths| paths.into_iter().next().ok_or(())) + .map_err(|_| SendError::PathNotFound) + } + fn enqueue_onion_message( &self, path: OnionMessagePath, contents: T, reply_path: Option, log_suffix: fmt::Arguments @@ -1053,20 +1094,48 @@ where ) } - fn handle_onion_message_response( + /// Handles the response to an [`OnionMessage`] based on its [`ResponseInstruction`], + /// enqueueing any response for sending. + /// + /// This function is useful for asynchronous handling of [`OnionMessage`]s. + /// Handlers have the option to return [`ResponseInstruction::NoResponse`], indicating that + /// no immediate response should be sent. Then, they can transfer the associated [`Responder`] + /// to another task responsible for generating the response asynchronously. Subsequently, when + /// the response is prepared and ready for sending, that task can invoke this method to enqueue + /// the response for delivery. + pub fn handle_onion_message_response( &self, response: ResponseInstruction - ) { - if let ResponseInstruction::WithoutReplyPath(response) = response { - let message_type = response.message.msg_type(); - let _ = self.find_path_and_enqueue_onion_message( - response.message, Destination::BlindedPath(response.reply_path), None, - format_args!( - "when responding with {} to an onion message with path_id {:02x?}", - message_type, - response.path_id - ) - ); - } + ) -> Result, SendError> { + let (response, create_reply_path) = match response { + ResponseInstruction::WithReplyPath(response) => (response, true), + ResponseInstruction::WithoutReplyPath(response) => (response, false), + ResponseInstruction::NoResponse => return Ok(None), + }; + + let message_type = response.message.msg_type(); + let reply_path = if create_reply_path { + match self.create_blinded_path() { + Ok(reply_path) => Some(reply_path), + Err(err) => { + log_trace!( + self.logger, + "Failed to create reply path when responding with {} to an onion message \ + with path_id {:02x?}: {:?}", + message_type, response.path_id, err + ); + return Err(err); + } + } + } else { None }; + + self.find_path_and_enqueue_onion_message( + response.message, Destination::BlindedPath(response.reply_path), reply_path, + format_args!( + "when responding with {} to an onion message with path_id {:02x?}", + message_type, + response.path_id + ) + ).map(|result| Some(result)) } #[cfg(test)] @@ -1172,14 +1241,14 @@ where |reply_path| Responder::new(reply_path, path_id) ); let response_instructions = self.offers_handler.handle_message(msg, responder); - self.handle_onion_message_response(response_instructions); + let _ = self.handle_onion_message_response(response_instructions); }, ParsedOnionMessageContents::Custom(msg) => { let responder = reply_path.map( |reply_path| Responder::new(reply_path, path_id) ); let response_instructions = self.custom_handler.handle_custom_message(msg, responder); - self.handle_onion_message_response(response_instructions); + let _ = self.handle_onion_message_response(response_instructions); }, } },