Merge pull request #2876 from TheBlueMatt/2024-02-2863-doc-nits
[rust-lightning] / lightning / src / onion_message / functional_tests.rs
1 // This file is Copyright its original authors, visible in version control
2 // history.
3 //
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
8 // licenses.
9
10 //! Onion message testing and test utilities live here.
11
12 use crate::blinded_path::BlindedPath;
13 use crate::events::{Event, EventsProvider};
14 use crate::ln::features::InitFeatures;
15 use crate::ln::msgs::{self, DecodeError, OnionMessageHandler, SocketAddress};
16 use crate::sign::{NodeSigner, Recipient};
17 use crate::util::ser::{FixedLengthReader, LengthReadable, Writeable, Writer};
18 use crate::util::test_utils;
19 use super::messenger::{CustomOnionMessageHandler, Destination, MessageRouter, OnionMessagePath, OnionMessenger, PendingOnionMessage, SendError};
20 use super::offers::{OffersMessage, OffersMessageHandler};
21 use super::packet::{OnionMessageContents, Packet};
22
23 use bitcoin::network::constants::Network;
24 use bitcoin::hashes::hex::FromHex;
25 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey, self};
26
27 use crate::io;
28 use crate::io_extras::read_to_end;
29 use crate::sync::{Arc, Mutex};
30
31 use crate::prelude::*;
32
33 struct MessengerNode {
34         node_id: PublicKey,
35         entropy_source: Arc<test_utils::TestKeysInterface>,
36         messenger: OnionMessenger<
37                 Arc<test_utils::TestKeysInterface>,
38                 Arc<test_utils::TestNodeSigner>,
39                 Arc<test_utils::TestLogger>,
40                 Arc<TestMessageRouter>,
41                 Arc<TestOffersMessageHandler>,
42                 Arc<TestCustomMessageHandler>
43         >,
44         custom_message_handler: Arc<TestCustomMessageHandler>,
45 }
46
47 struct TestMessageRouter {}
48
49 impl MessageRouter for TestMessageRouter {
50         fn find_path(
51                 &self, _sender: PublicKey, _peers: Vec<PublicKey>, destination: Destination
52         ) -> Result<OnionMessagePath, ()> {
53                 Ok(OnionMessagePath {
54                         intermediate_nodes: vec![],
55                         destination,
56                         first_node_addresses:
57                                 Some(vec![SocketAddress::TcpIpV4 { addr: [127, 0, 0, 1], port: 1000 }]),
58                 })
59         }
60
61         fn create_blinded_paths<
62                 T: secp256k1::Signing + secp256k1::Verification
63         >(
64                 &self, _recipient: PublicKey, _peers: Vec<PublicKey>, _secp_ctx: &Secp256k1<T>,
65         ) -> Result<Vec<BlindedPath>, ()> {
66                 unreachable!()
67         }
68 }
69
70 struct TestOffersMessageHandler {}
71
72 impl OffersMessageHandler for TestOffersMessageHandler {
73         fn handle_message(&self, _message: OffersMessage) -> Option<OffersMessage> {
74                 None
75         }
76 }
77
78 #[derive(Clone, Debug, PartialEq)]
79 enum TestCustomMessage {
80         Request,
81         Response,
82 }
83
84 const CUSTOM_REQUEST_MESSAGE_TYPE: u64 = 4242;
85 const CUSTOM_RESPONSE_MESSAGE_TYPE: u64 = 4343;
86 const CUSTOM_REQUEST_MESSAGE_CONTENTS: [u8; 32] = [42; 32];
87 const CUSTOM_RESPONSE_MESSAGE_CONTENTS: [u8; 32] = [43; 32];
88
89 impl OnionMessageContents for TestCustomMessage {
90         fn tlv_type(&self) -> u64 {
91                 match self {
92                         TestCustomMessage::Request => CUSTOM_REQUEST_MESSAGE_TYPE,
93                         TestCustomMessage::Response => CUSTOM_RESPONSE_MESSAGE_TYPE,
94                 }
95         }
96 }
97
98 impl Writeable for TestCustomMessage {
99         fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
100                 match self {
101                         TestCustomMessage::Request => Ok(CUSTOM_REQUEST_MESSAGE_CONTENTS.write(w)?),
102                         TestCustomMessage::Response => Ok(CUSTOM_RESPONSE_MESSAGE_CONTENTS.write(w)?),
103                 }
104         }
105 }
106
107 struct TestCustomMessageHandler {
108         expected_messages: Mutex<VecDeque<TestCustomMessage>>,
109 }
110
111 impl TestCustomMessageHandler {
112         fn new() -> Self {
113                 Self { expected_messages: Mutex::new(VecDeque::new()) }
114         }
115
116         fn expect_message(&self, message: TestCustomMessage) {
117                 self.expected_messages.lock().unwrap().push_back(message);
118         }
119 }
120
121 impl Drop for TestCustomMessageHandler {
122         fn drop(&mut self) {
123                 #[cfg(feature = "std")] {
124                         if std::thread::panicking() {
125                                 return;
126                         }
127                 }
128                 assert!(self.expected_messages.lock().unwrap().is_empty());
129         }
130 }
131
132 impl CustomOnionMessageHandler for TestCustomMessageHandler {
133         type CustomMessage = TestCustomMessage;
134         fn handle_custom_message(&self, msg: Self::CustomMessage) -> Option<Self::CustomMessage> {
135                 match self.expected_messages.lock().unwrap().pop_front() {
136                         Some(expected_msg) => assert_eq!(expected_msg, msg),
137                         None => panic!("Unexpected message: {:?}", msg),
138                 }
139
140                 match msg {
141                         TestCustomMessage::Request => Some(TestCustomMessage::Response),
142                         TestCustomMessage::Response => None,
143                 }
144         }
145         fn read_custom_message<R: io::Read>(&self, message_type: u64, buffer: &mut R) -> Result<Option<Self::CustomMessage>, DecodeError> where Self: Sized {
146                 match message_type {
147                         CUSTOM_REQUEST_MESSAGE_TYPE => {
148                                 let buf = read_to_end(buffer)?;
149                                 assert_eq!(buf, CUSTOM_REQUEST_MESSAGE_CONTENTS);
150                                 Ok(Some(TestCustomMessage::Request))
151                         },
152                         CUSTOM_RESPONSE_MESSAGE_TYPE => {
153                                 let buf = read_to_end(buffer)?;
154                                 assert_eq!(buf, CUSTOM_RESPONSE_MESSAGE_CONTENTS);
155                                 Ok(Some(TestCustomMessage::Response))
156                         },
157                         _ => Ok(None),
158                 }
159         }
160         fn release_pending_custom_messages(&self) -> Vec<PendingOnionMessage<Self::CustomMessage>> {
161                 vec![]
162         }
163 }
164
165 fn create_nodes(num_messengers: u8) -> Vec<MessengerNode> {
166         let secrets = (1..=num_messengers)
167                 .into_iter()
168                 .map(|i| SecretKey::from_slice(&[i; 32]).unwrap())
169                 .collect();
170         create_nodes_using_secrets(secrets)
171 }
172
173 fn create_nodes_using_secrets(secrets: Vec<SecretKey>) -> Vec<MessengerNode> {
174         let mut nodes = Vec::new();
175         for (i, secret_key) in secrets.into_iter().enumerate() {
176                 let logger = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
177                 let seed = [i as u8; 32];
178                 let entropy_source = Arc::new(test_utils::TestKeysInterface::new(&seed, Network::Testnet));
179                 let node_signer = Arc::new(test_utils::TestNodeSigner::new(secret_key));
180
181                 let message_router = Arc::new(TestMessageRouter {});
182                 let offers_message_handler = Arc::new(TestOffersMessageHandler {});
183                 let custom_message_handler = Arc::new(TestCustomMessageHandler::new());
184                 nodes.push(MessengerNode {
185                         node_id: node_signer.get_node_id(Recipient::Node).unwrap(),
186                         entropy_source: entropy_source.clone(),
187                         messenger: OnionMessenger::new(
188                                 entropy_source, node_signer, logger.clone(), message_router,
189                                 offers_message_handler, custom_message_handler.clone()
190                         ),
191                         custom_message_handler,
192                 });
193         }
194         for i in 0..nodes.len() - 1 {
195                 connect_peers(&nodes[i], &nodes[i + 1]);
196         }
197         nodes
198 }
199
200 fn connect_peers(node_a: &MessengerNode, node_b: &MessengerNode) {
201         let mut features = InitFeatures::empty();
202         features.set_onion_messages_optional();
203         let init_msg = msgs::Init { features, networks: None, remote_network_address: None };
204         node_a.messenger.peer_connected(&node_b.node_id, &init_msg.clone(), true).unwrap();
205         node_b.messenger.peer_connected(&node_a.node_id, &init_msg.clone(), false).unwrap();
206 }
207
208 fn disconnect_peers(node_a: &MessengerNode, node_b: &MessengerNode) {
209         node_a.messenger.peer_disconnected(&node_b.node_id);
210         node_b.messenger.peer_disconnected(&node_a.node_id);
211 }
212
213 fn release_events(node: &MessengerNode) -> Vec<Event> {
214         let events = core::cell::RefCell::new(Vec::new());
215         node.messenger.process_pending_events(&|e| events.borrow_mut().push(e));
216         events.into_inner()
217 }
218
219 fn pass_along_path(path: &Vec<MessengerNode>) {
220         let mut prev_node = &path[0];
221         for node in path.into_iter().skip(1) {
222                 let events = prev_node.messenger.release_pending_msgs();
223                 let onion_msg =  {
224                         let msgs = events.get(&node.node_id).unwrap();
225                         assert_eq!(msgs.len(), 1);
226                         msgs[0].clone()
227                 };
228                 node.messenger.handle_onion_message(&prev_node.node_id, &onion_msg);
229                 prev_node = node;
230         }
231 }
232
233 #[test]
234 fn one_unblinded_hop() {
235         let nodes = create_nodes(2);
236         let test_msg = TestCustomMessage::Response;
237
238         let path = OnionMessagePath {
239                 intermediate_nodes: vec![],
240                 destination: Destination::Node(nodes[1].node_id),
241                 first_node_addresses: None,
242         };
243         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
244         nodes[1].custom_message_handler.expect_message(TestCustomMessage::Response);
245         pass_along_path(&nodes);
246 }
247
248 #[test]
249 fn two_unblinded_hops() {
250         let nodes = create_nodes(3);
251         let test_msg = TestCustomMessage::Response;
252
253         let path = OnionMessagePath {
254                 intermediate_nodes: vec![nodes[1].node_id],
255                 destination: Destination::Node(nodes[2].node_id),
256                 first_node_addresses: None,
257         };
258         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
259         nodes[2].custom_message_handler.expect_message(TestCustomMessage::Response);
260         pass_along_path(&nodes);
261 }
262
263 #[test]
264 fn one_blinded_hop() {
265         let nodes = create_nodes(2);
266         let test_msg = TestCustomMessage::Response;
267
268         let secp_ctx = Secp256k1::new();
269         let blinded_path = BlindedPath::new_for_message(&[nodes[1].node_id], &*nodes[1].entropy_source, &secp_ctx).unwrap();
270         let path = OnionMessagePath {
271                 intermediate_nodes: vec![],
272                 destination: Destination::BlindedPath(blinded_path),
273                 first_node_addresses: None,
274         };
275         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
276         nodes[1].custom_message_handler.expect_message(TestCustomMessage::Response);
277         pass_along_path(&nodes);
278 }
279
280 #[test]
281 fn two_unblinded_two_blinded() {
282         let nodes = create_nodes(5);
283         let test_msg = TestCustomMessage::Response;
284
285         let secp_ctx = Secp256k1::new();
286         let blinded_path = BlindedPath::new_for_message(&[nodes[3].node_id, nodes[4].node_id], &*nodes[4].entropy_source, &secp_ctx).unwrap();
287         let path = OnionMessagePath {
288                 intermediate_nodes: vec![nodes[1].node_id, nodes[2].node_id],
289                 destination: Destination::BlindedPath(blinded_path),
290                 first_node_addresses: None,
291         };
292
293         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
294         nodes[4].custom_message_handler.expect_message(TestCustomMessage::Response);
295         pass_along_path(&nodes);
296 }
297
298 #[test]
299 fn three_blinded_hops() {
300         let nodes = create_nodes(4);
301         let test_msg = TestCustomMessage::Response;
302
303         let secp_ctx = Secp256k1::new();
304         let blinded_path = BlindedPath::new_for_message(&[nodes[1].node_id, nodes[2].node_id, nodes[3].node_id], &*nodes[3].entropy_source, &secp_ctx).unwrap();
305         let path = OnionMessagePath {
306                 intermediate_nodes: vec![],
307                 destination: Destination::BlindedPath(blinded_path),
308                 first_node_addresses: None,
309         };
310
311         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
312         nodes[3].custom_message_handler.expect_message(TestCustomMessage::Response);
313         pass_along_path(&nodes);
314 }
315
316 #[test]
317 fn too_big_packet_error() {
318         // Make sure we error as expected if a packet is too big to send.
319         let nodes = create_nodes(2);
320         let test_msg = TestCustomMessage::Response;
321
322         let hop_node_id = nodes[1].node_id;
323         let hops = vec![hop_node_id; 400];
324         let path = OnionMessagePath {
325                 intermediate_nodes: hops,
326                 destination: Destination::Node(hop_node_id),
327                 first_node_addresses: None,
328         };
329         let err = nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap_err();
330         assert_eq!(err, SendError::TooBigPacket);
331 }
332
333 #[test]
334 fn we_are_intro_node() {
335         // If we are sending straight to a blinded path and we are the introduction node, we need to
336         // advance the blinded path by 1 hop so the second hop is the new introduction node.
337         let mut nodes = create_nodes(3);
338         let test_msg = TestCustomMessage::Response;
339
340         let secp_ctx = Secp256k1::new();
341         let blinded_path = BlindedPath::new_for_message(&[nodes[0].node_id, nodes[1].node_id, nodes[2].node_id], &*nodes[2].entropy_source, &secp_ctx).unwrap();
342         let path = OnionMessagePath {
343                 intermediate_nodes: vec![],
344                 destination: Destination::BlindedPath(blinded_path),
345                 first_node_addresses: None,
346         };
347
348         nodes[0].messenger.send_onion_message_using_path(path, test_msg.clone(), None).unwrap();
349         nodes[2].custom_message_handler.expect_message(TestCustomMessage::Response);
350         pass_along_path(&nodes);
351
352         // Try with a two-hop blinded path where we are the introduction node.
353         let blinded_path = BlindedPath::new_for_message(&[nodes[0].node_id, nodes[1].node_id], &*nodes[1].entropy_source, &secp_ctx).unwrap();
354         let path = OnionMessagePath {
355                 intermediate_nodes: vec![],
356                 destination: Destination::BlindedPath(blinded_path),
357                 first_node_addresses: None,
358         };
359         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
360         nodes[1].custom_message_handler.expect_message(TestCustomMessage::Response);
361         nodes.remove(2);
362         pass_along_path(&nodes);
363 }
364
365 #[test]
366 fn invalid_blinded_path_error() {
367         // Make sure we error as expected if a provided blinded path has 0 or 1 hops.
368         let nodes = create_nodes(3);
369         let test_msg = TestCustomMessage::Response;
370
371         // 0 hops
372         let secp_ctx = Secp256k1::new();
373         let mut blinded_path = BlindedPath::new_for_message(&[nodes[1].node_id, nodes[2].node_id], &*nodes[2].entropy_source, &secp_ctx).unwrap();
374         blinded_path.blinded_hops.clear();
375         let path = OnionMessagePath {
376                 intermediate_nodes: vec![],
377                 destination: Destination::BlindedPath(blinded_path),
378                 first_node_addresses: None,
379         };
380         let err = nodes[0].messenger.send_onion_message_using_path(path, test_msg.clone(), None).unwrap_err();
381         assert_eq!(err, SendError::TooFewBlindedHops);
382 }
383
384 #[test]
385 fn reply_path() {
386         let mut nodes = create_nodes(4);
387         let test_msg = TestCustomMessage::Request;
388         let secp_ctx = Secp256k1::new();
389
390         // Destination::Node
391         let path = OnionMessagePath {
392                 intermediate_nodes: vec![nodes[1].node_id, nodes[2].node_id],
393                 destination: Destination::Node(nodes[3].node_id),
394                 first_node_addresses: None,
395         };
396         let reply_path = BlindedPath::new_for_message(&[nodes[2].node_id, nodes[1].node_id, nodes[0].node_id], &*nodes[0].entropy_source, &secp_ctx).unwrap();
397         nodes[0].messenger.send_onion_message_using_path(path, test_msg.clone(), Some(reply_path)).unwrap();
398         nodes[3].custom_message_handler.expect_message(TestCustomMessage::Request);
399         pass_along_path(&nodes);
400         // Make sure the last node successfully decoded the reply path.
401         nodes[0].custom_message_handler.expect_message(TestCustomMessage::Response);
402         nodes.reverse();
403         pass_along_path(&nodes);
404
405         // Destination::BlindedPath
406         let blinded_path = BlindedPath::new_for_message(&[nodes[1].node_id, nodes[2].node_id, nodes[3].node_id], &*nodes[3].entropy_source, &secp_ctx).unwrap();
407         let path = OnionMessagePath {
408                 intermediate_nodes: vec![],
409                 destination: Destination::BlindedPath(blinded_path),
410                 first_node_addresses: None,
411         };
412         let reply_path = BlindedPath::new_for_message(&[nodes[2].node_id, nodes[1].node_id, nodes[0].node_id], &*nodes[0].entropy_source, &secp_ctx).unwrap();
413
414         nodes[0].messenger.send_onion_message_using_path(path, test_msg, Some(reply_path)).unwrap();
415         nodes[3].custom_message_handler.expect_message(TestCustomMessage::Request);
416         pass_along_path(&nodes);
417
418         // Make sure the last node successfully decoded the reply path.
419         nodes[0].custom_message_handler.expect_message(TestCustomMessage::Response);
420         nodes.reverse();
421         pass_along_path(&nodes);
422 }
423
424 #[test]
425 fn invalid_custom_message_type() {
426         let nodes = create_nodes(2);
427
428         #[derive(Debug)]
429         struct InvalidCustomMessage{}
430         impl OnionMessageContents for InvalidCustomMessage {
431                 fn tlv_type(&self) -> u64 {
432                         // Onion message contents must have a TLV >= 64.
433                         63
434                 }
435         }
436
437         impl Writeable for InvalidCustomMessage {
438                 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> { unreachable!() }
439         }
440
441         let test_msg = InvalidCustomMessage {};
442         let path = OnionMessagePath {
443                 intermediate_nodes: vec![],
444                 destination: Destination::Node(nodes[1].node_id),
445                 first_node_addresses: None,
446         };
447         let err = nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap_err();
448         assert_eq!(err, SendError::InvalidMessage);
449 }
450
451 #[test]
452 fn peer_buffer_full() {
453         let nodes = create_nodes(2);
454         let test_msg = TestCustomMessage::Request;
455         let path = OnionMessagePath {
456                 intermediate_nodes: vec![],
457                 destination: Destination::Node(nodes[1].node_id),
458                 first_node_addresses: None,
459         };
460         for _ in 0..188 { // Based on MAX_PER_PEER_BUFFER_SIZE in OnionMessenger
461                 nodes[0].messenger.send_onion_message_using_path(path.clone(), test_msg.clone(), None).unwrap();
462         }
463         let err = nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap_err();
464         assert_eq!(err, SendError::BufferFull);
465 }
466
467 #[test]
468 fn many_hops() {
469         // Check we can send over a route with many hops. This will exercise our logic for onion messages
470         // of size [`crate::onion_message::packet::BIG_PACKET_HOP_DATA_LEN`].
471         let num_nodes: usize = 25;
472         let nodes = create_nodes(num_nodes as u8);
473         let test_msg = TestCustomMessage::Response;
474
475         let mut intermediate_nodes = vec![];
476         for i in 1..(num_nodes-1) {
477                 intermediate_nodes.push(nodes[i].node_id);
478         }
479
480         let path = OnionMessagePath {
481                 intermediate_nodes,
482                 destination: Destination::Node(nodes[num_nodes-1].node_id),
483                 first_node_addresses: None,
484         };
485         nodes[0].messenger.send_onion_message_using_path(path, test_msg, None).unwrap();
486         nodes[num_nodes-1].custom_message_handler.expect_message(TestCustomMessage::Response);
487         pass_along_path(&nodes);
488 }
489
490 #[test]
491 fn requests_peer_connection_for_buffered_messages() {
492         let nodes = create_nodes(3);
493         let message = TestCustomMessage::Request;
494         let secp_ctx = Secp256k1::new();
495         let blinded_path = BlindedPath::new_for_message(
496                 &[nodes[1].node_id, nodes[2].node_id], &*nodes[0].entropy_source, &secp_ctx
497         ).unwrap();
498         let destination = Destination::BlindedPath(blinded_path);
499
500         // Buffer an onion message for a connected peer
501         nodes[0].messenger.send_onion_message(message.clone(), destination.clone(), None).unwrap();
502         assert!(release_events(&nodes[0]).is_empty());
503         assert!(nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).is_some());
504         assert!(nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).is_none());
505
506         // Buffer an onion message for a disconnected peer
507         disconnect_peers(&nodes[0], &nodes[1]);
508         assert!(nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).is_none());
509         nodes[0].messenger.send_onion_message(message, destination, None).unwrap();
510
511         // Check that a ConnectionNeeded event for the peer is provided
512         let events = release_events(&nodes[0]);
513         assert_eq!(events.len(), 1);
514         match &events[0] {
515                 Event::ConnectionNeeded { node_id, .. } => assert_eq!(*node_id, nodes[1].node_id),
516                 e => panic!("Unexpected event: {:?}", e),
517         }
518
519         // Release the buffered onion message when reconnected
520         connect_peers(&nodes[0], &nodes[1]);
521         assert!(nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).is_some());
522         assert!(nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).is_none());
523 }
524
525 #[test]
526 fn drops_buffered_messages_waiting_for_peer_connection() {
527         let nodes = create_nodes(3);
528         let message = TestCustomMessage::Request;
529         let secp_ctx = Secp256k1::new();
530         let blinded_path = BlindedPath::new_for_message(
531                 &[nodes[1].node_id, nodes[2].node_id], &*nodes[0].entropy_source, &secp_ctx
532         ).unwrap();
533         let destination = Destination::BlindedPath(blinded_path);
534
535         // Buffer an onion message for a disconnected peer
536         disconnect_peers(&nodes[0], &nodes[1]);
537         nodes[0].messenger.send_onion_message(message, destination, None).unwrap();
538
539         // Release the event so the timer can start ticking
540         let events = release_events(&nodes[0]);
541         assert_eq!(events.len(), 1);
542         match &events[0] {
543                 Event::ConnectionNeeded { node_id, .. } => assert_eq!(*node_id, nodes[1].node_id),
544                 e => panic!("Unexpected event: {:?}", e),
545         }
546
547         // Drop buffered messages for a disconnected peer after some timer ticks
548         use crate::onion_message::messenger::MAX_TIMER_TICKS;
549         for _ in 0..=MAX_TIMER_TICKS {
550                 nodes[0].messenger.timer_tick_occurred();
551         }
552         connect_peers(&nodes[0], &nodes[1]);
553         assert!(nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).is_none());
554 }
555
556 #[test]
557 fn spec_test_vector() {
558         let secret_keys = [
559                 "4141414141414141414141414141414141414141414141414141414141414141", // Alice
560                 "4242424242424242424242424242424242424242424242424242424242424242", // Bob
561                 "4343434343434343434343434343434343434343434343434343434343434343", // Carol
562                 "4444444444444444444444444444444444444444444444444444444444444444", // Dave
563         ]
564                 .iter()
565                 .map(|secret| SecretKey::from_slice(&<Vec<u8>>::from_hex(secret).unwrap()).unwrap())
566                 .collect();
567         let nodes = create_nodes_using_secrets(secret_keys);
568
569         // Hardcode the sender->Alice onion message, because it includes an unknown TLV of type 1, which
570         // LDK doesn't support constructing.
571         let sender_to_alice_packet_bytes = <Vec<u8>>::from_hex("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").unwrap();
572         let sender_to_alice_packet_bytes_len = sender_to_alice_packet_bytes.len() as u64;
573         let mut reader = io::Cursor::new(sender_to_alice_packet_bytes);
574         let mut packet_reader = FixedLengthReader::new(&mut reader, sender_to_alice_packet_bytes_len);
575         let sender_to_alice_packet: Packet =
576                 <Packet as LengthReadable>::read(&mut packet_reader).unwrap();
577         let secp_ctx = Secp256k1::new();
578         let sender_to_alice_om = msgs::OnionMessage {
579                 blinding_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&<Vec<u8>>::from_hex("6363636363636363636363636363636363636363636363636363636363636363").unwrap()).unwrap()),
580                 onion_routing_packet: sender_to_alice_packet,
581         };
582         // The spec test vectors prepend the OM message type (513) to the encoded onion message strings,
583         // which is why the asserted strings differ slightly from the spec.
584         assert_eq!(sender_to_alice_om.encode(), <Vec<u8>>::from_hex("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").unwrap());
585         let sender_dummy_node_id = PublicKey::from_slice(&[2; 33]).unwrap();
586         nodes[0].messenger.handle_onion_message(&sender_dummy_node_id, &sender_to_alice_om);
587         let alice_to_bob_om = nodes[0].messenger.next_onion_message_for_peer(nodes[1].node_id).unwrap();
588         assert_eq!(alice_to_bob_om.encode(), <Vec<u8>>::from_hex("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").unwrap());
589         nodes[1].messenger.handle_onion_message(&nodes[0].node_id, &alice_to_bob_om);
590         let bob_to_carol_om = nodes[1].messenger.next_onion_message_for_peer(nodes[2].node_id).unwrap();
591         assert_eq!(bob_to_carol_om.encode(), <Vec<u8>>::from_hex("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").unwrap());
592         nodes[2].messenger.handle_onion_message(&nodes[1].node_id, &bob_to_carol_om);
593         let carol_to_dave_om = nodes[2].messenger.next_onion_message_for_peer(nodes[3].node_id).unwrap();
594         assert_eq!(carol_to_dave_om.encode(), <Vec<u8>>::from_hex("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").unwrap());
595         // Dave handles the onion message but he'll log that he errored while decoding the hop data
596         // because he sees it as an empty onion message (the only contents of the sender's OM is "hello"
597         // with TLV type 1, which Dave ignores because (1) it's odd and he can't understand it and (2) LDK
598         // only attempts to parse custom OM TLVs with type > 64).
599         nodes[3].messenger.handle_onion_message(&nodes[2].node_id, &carol_to_dave_om);
600 }