Merge pull request #2277 from valentinewallace/2023-05-fix-big-oms

Fix large onion message packet generation

diff --git a/lightning/src/ln/onion_utils.rs b/lightning/src/ln/onion_utils.rs
index ebcf83bd90dc2d0db68c5300e50cf2f6b06dd718..b7759d26f5c55eaee02900c3d4ebcc3c655f3af0 100644 (file)
--- a/lightning/src/ln/onion_utils.rs
+++ b/lightning/src/ln/onion_utils.rs
@@ -324,7 +324,8 @@ fn construct_onion_packet_with_init_noise<HD: Writeable, P: Packet>(
                chacha.process_in_place(packet_data);
 
                if i == 0 {
-                       packet_data[ONION_DATA_LEN - filler.len()..ONION_DATA_LEN].copy_from_slice(&filler[..]);
+                       let onion_data_len = packet_data.len();
+                       packet_data[onion_data_len - filler.len()..onion_data_len].copy_from_slice(&filler[..]);
                }
 
                let mut hmac = HmacEngine::<Sha256>::new(&keys.mu);

diff --git a/lightning/src/onion_message/functional_tests.rs b/lightning/src/onion_message/functional_tests.rs
index 8eaf8ad163e2eaacdcaa768c1fad905be41670f7..98fcdb680ee03abd1f2c8f3730c0b740bb75977f 100644 (file)
--- a/lightning/src/onion_message/functional_tests.rs
+++ b/lightning/src/onion_message/functional_tests.rs
@@ -20,6 +20,7 @@ use crate::util::test_utils;
 use bitcoin::network::constants::Network;
 use bitcoin::secp256k1::{PublicKey, Secp256k1};
 
+use core::sync::atomic::{AtomicU16, Ordering};
 use crate::io;
 use crate::io_extras::read_to_end;
 use crate::sync::Arc;
@@ -27,6 +28,7 @@ use crate::sync::Arc;
 struct MessengerNode {
        keys_manager: Arc<test_utils::TestKeysInterface>,
        messenger: OnionMessenger<Arc<test_utils::TestKeysInterface>, Arc<test_utils::TestKeysInterface>, Arc<test_utils::TestLogger>, Arc<TestCustomMessageHandler>>,
+       custom_message_handler: Arc<TestCustomMessageHandler>,
        logger: Arc<test_utils::TestLogger>,
 }
 
@@ -54,11 +56,32 @@ impl Writeable for TestCustomMessage {
        }
 }
 
-struct TestCustomMessageHandler {}
+struct TestCustomMessageHandler {
+       num_messages_expected: AtomicU16,
+}
+
+impl TestCustomMessageHandler {
+       fn new() -> Self {
+               Self { num_messages_expected: AtomicU16::new(0) }
+       }
+}
+
+impl Drop for TestCustomMessageHandler {
+       fn drop(&mut self) {
+               #[cfg(feature = "std")] {
+                       if std::thread::panicking() {
+                               return;
+                       }
+               }
+               assert_eq!(self.num_messages_expected.load(Ordering::SeqCst), 0);
+       }
+}
 
 impl CustomOnionMessageHandler for TestCustomMessageHandler {
        type CustomMessage = TestCustomMessage;
-       fn handle_custom_message(&self, _msg: Self::CustomMessage) {}
+       fn handle_custom_message(&self, _msg: Self::CustomMessage) {
+               self.num_messages_expected.fetch_sub(1, Ordering::SeqCst);
+       }
        fn read_custom_message<R: io::Read>(&self, message_type: u64, buffer: &mut R) -> Result<Option<Self::CustomMessage>, DecodeError> where Self: Sized {
                if message_type == CUSTOM_MESSAGE_TYPE {
                        let buf = read_to_end(buffer)?;
@@ -75,9 +98,11 @@ fn create_nodes(num_messengers: u8) -> Vec<MessengerNode> {
                let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
                let seed = [i as u8; 32];
                let keys_manager = Arc::new(test_utils::TestKeysInterface::new(&seed, Network::Testnet));
+               let custom_message_handler = Arc::new(TestCustomMessageHandler::new());
                nodes.push(MessengerNode {
                        keys_manager: keys_manager.clone(),
-                       messenger: OnionMessenger::new(keys_manager.clone(), keys_manager.clone(), logger.clone(), Arc::new(TestCustomMessageHandler {})),
+                       messenger: OnionMessenger::new(keys_manager.clone(), keys_manager.clone(), logger.clone(), custom_message_handler.clone()),
+                       custom_message_handler,
                        logger,
                });
        }
@@ -92,10 +117,10 @@ fn create_nodes(num_messengers: u8) -> Vec<MessengerNode> {
        nodes
 }
 
-fn pass_along_path(path: &Vec<MessengerNode>, expected_path_id: Option<[u8; 32]>) {
+fn pass_along_path(path: &Vec<MessengerNode>) {
+       path[path.len() - 1].custom_message_handler.num_messages_expected.fetch_add(1, Ordering::SeqCst);
        let mut prev_node = &path[0];
-       let num_nodes = path.len();
-       for (idx, node) in path.into_iter().skip(1).enumerate() {
+       for node in path.into_iter().skip(1) {
                let events = prev_node.messenger.release_pending_msgs();
                let onion_msg =  {
                        let msgs = events.get(&node.get_node_pk()).unwrap();
@@ -103,11 +128,6 @@ fn pass_along_path(path: &Vec<MessengerNode>, expected_path_id: Option<[u8; 32]>
                        msgs[0].clone()
                };
                node.messenger.handle_onion_message(&prev_node.get_node_pk(), &onion_msg);
-               if idx == num_nodes - 1 {
-                       node.logger.assert_log_contains(
-                               "lightning::onion_message::messenger",
-                               &format!("Received an onion message with path_id: {:02x?}", expected_path_id), 1);
-               }
                prev_node = node;
        }
 }
@@ -118,7 +138,7 @@ fn one_hop() {
        let test_msg = OnionMessageContents::Custom(TestCustomMessage {});
 
        nodes[0].messenger.send_onion_message(&[], Destination::Node(nodes[1].get_node_pk()), test_msg, None).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
 }
 
 #[test]
@@ -127,7 +147,7 @@ fn two_unblinded_hops() {
        let test_msg = OnionMessageContents::Custom(TestCustomMessage {});
 
        nodes[0].messenger.send_onion_message(&[nodes[1].get_node_pk()], Destination::Node(nodes[2].get_node_pk()), test_msg, None).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
 }
 
 #[test]
@@ -139,7 +159,7 @@ fn two_unblinded_two_blinded() {
        let blinded_path = BlindedPath::new_for_message(&[nodes[3].get_node_pk(), nodes[4].get_node_pk()], &*nodes[4].keys_manager, &secp_ctx).unwrap();
 
        nodes[0].messenger.send_onion_message(&[nodes[1].get_node_pk(), nodes[2].get_node_pk()], Destination::BlindedPath(blinded_path), test_msg, None).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
 }
 
 #[test]
@@ -151,7 +171,7 @@ fn three_blinded_hops() {
        let blinded_path = BlindedPath::new_for_message(&[nodes[1].get_node_pk(), nodes[2].get_node_pk(), nodes[3].get_node_pk()], &*nodes[3].keys_manager, &secp_ctx).unwrap();
 
        nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), test_msg, None).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
 }
 
 #[test]
@@ -177,13 +197,13 @@ fn we_are_intro_node() {
        let blinded_path = BlindedPath::new_for_message(&[nodes[0].get_node_pk(), nodes[1].get_node_pk(), nodes[2].get_node_pk()], &*nodes[2].keys_manager, &secp_ctx).unwrap();
 
        nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg.clone()), None).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
 
        // Try with a two-hop blinded path where we are the introduction node.
        let blinded_path = BlindedPath::new_for_message(&[nodes[0].get_node_pk(), nodes[1].get_node_pk()], &*nodes[1].keys_manager, &secp_ctx).unwrap();
        nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg), None).unwrap();
        nodes.remove(2);
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
 }
 
 #[test]
@@ -216,7 +236,7 @@ fn reply_path() {
        // Destination::Node
        let reply_path = BlindedPath::new_for_message(&[nodes[2].get_node_pk(), nodes[1].get_node_pk(), nodes[0].get_node_pk()], &*nodes[0].keys_manager, &secp_ctx).unwrap();
        nodes[0].messenger.send_onion_message(&[nodes[1].get_node_pk(), nodes[2].get_node_pk()], Destination::Node(nodes[3].get_node_pk()), OnionMessageContents::Custom(test_msg.clone()), Some(reply_path)).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
        // Make sure the last node successfully decoded the reply path.
        nodes[3].logger.assert_log_contains(
                "lightning::onion_message::messenger",
@@ -227,7 +247,7 @@ fn reply_path() {
        let reply_path = BlindedPath::new_for_message(&[nodes[2].get_node_pk(), nodes[1].get_node_pk(), nodes[0].get_node_pk()], &*nodes[0].keys_manager, &secp_ctx).unwrap();
 
        nodes[0].messenger.send_onion_message(&[], Destination::BlindedPath(blinded_path), OnionMessageContents::Custom(test_msg), Some(reply_path)).unwrap();
-       pass_along_path(&nodes, None);
+       pass_along_path(&nodes);
        nodes[3].logger.assert_log_contains(
                "lightning::onion_message::messenger",
                &format!("Received an onion message with path_id None and a reply_path"), 2);
@@ -264,3 +284,20 @@ fn peer_buffer_full() {
        let err = nodes[0].messenger.send_onion_message(&[], Destination::Node(nodes[1].get_node_pk()), OnionMessageContents::Custom(test_msg), None).unwrap_err();
        assert_eq!(err, SendError::BufferFull);
 }
+
+#[test]
+fn many_hops() {
+       // Check we can send over a route with many hops. This will exercise our logic for onion messages
+       // 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 = OnionMessageContents::Custom(TestCustomMessage {});
+
+       let mut intermediates = vec![];
+       for i in 1..(num_nodes-1) {
+               intermediates.push(nodes[i].get_node_pk());
+       }
+
+       nodes[0].messenger.send_onion_message(&intermediates, Destination::Node(nodes[num_nodes-1].get_node_pk()), test_msg, None).unwrap();
+       pass_along_path(&nodes);
+}

diff --git a/pending_changelog/big-om-error.txt b/pending_changelog/big-om-error.txt
new file mode 100644 (file)
index 0000000..6f2ce89
--- /dev/null
+++ b/pending_changelog/big-om-error.txt
@@ -0,0 +1,4 @@
+## Bug Fixes
+
+* Fixed sending large onion messages, which previously would result in an HMAC error on the second
+       hop (#2277).