Introduce tests to check verify reply path diversification

diff --git a/lightning/src/ln/offers_tests.rs b/lightning/src/ln/offers_tests.rs
index 041cc18fa69320293cb63ed9ecf8dd7a701e5954..cdd78d02ca8f5d7774ffbae59f47f2c6ab3baa4c 100644 (file)
--- a/lightning/src/ln/offers_tests.rs
+++ b/lightning/src/ln/offers_tests.rs
@@ -878,6 +878,170 @@ fn pays_for_refund_without_blinded_paths() {
        expect_recent_payment!(bob, RecentPaymentDetails::Fulfilled, payment_id);
 }
 
+/// This test checks that when multiple potential introduction nodes are available for the payer,
+/// multiple `invoice_request` messages are sent for the offer, each with a different `reply_path`.
+#[test]
+fn send_invoice_requests_with_distinct_reply_path() {
+       let mut accept_forward_cfg = test_default_channel_config();
+       accept_forward_cfg.accept_forwards_to_priv_channels = true;
+
+       let mut features = channelmanager::provided_init_features(&accept_forward_cfg);
+       features.set_onion_messages_optional();
+       features.set_route_blinding_optional();
+
+       let chanmon_cfgs = create_chanmon_cfgs(7);
+       let node_cfgs = create_node_cfgs(7, &chanmon_cfgs);
+
+       *node_cfgs[1].override_init_features.borrow_mut() = Some(features);
+
+       let node_chanmgrs = create_node_chanmgrs(
+               7, &node_cfgs, &[None, Some(accept_forward_cfg), None, None, None, None, None]
+       );
+       let nodes = create_network(7, &node_cfgs, &node_chanmgrs);
+
+       create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 1_000_000_000);
+       create_unannounced_chan_between_nodes_with_value(&nodes, 2, 3, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 1, 4, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 1, 5, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 2, 4, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 2, 5, 10_000_000, 1_000_000_000);
+
+       // Introduce another potential introduction node, node[6], as a candidate
+       create_unannounced_chan_between_nodes_with_value(&nodes, 3, 6, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 2, 6, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 4, 6, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 5, 6, 10_000_000, 1_000_000_000);
+
+       let (alice, bob, charlie, david) = (&nodes[0], &nodes[1], &nodes[2], &nodes[3]);
+       let alice_id = alice.node.get_our_node_id();
+       let bob_id = bob.node.get_our_node_id();
+       let charlie_id = charlie.node.get_our_node_id();
+       let david_id = david.node.get_our_node_id();
+
+       disconnect_peers(alice, &[charlie, david, &nodes[4], &nodes[5], &nodes[6]]);
+       disconnect_peers(david, &[bob, &nodes[4], &nodes[5]]);
+
+       let offer = alice.node
+               .create_offer_builder(None)
+               .unwrap()
+               .amount_msats(10_000_000)
+               .build().unwrap();
+       assert_ne!(offer.signing_pubkey(), Some(alice_id));
+       assert!(!offer.paths().is_empty());
+       for path in offer.paths() {
+               assert_eq!(path.introduction_node, IntroductionNode::NodeId(bob_id));
+       }
+
+       let payment_id = PaymentId([1; 32]);
+       david.node.pay_for_offer(&offer, None, None, None, payment_id, Retry::Attempts(0), None)
+               .unwrap();
+       expect_recent_payment!(david, RecentPaymentDetails::AwaitingInvoice, payment_id);
+       connect_peers(david, bob);
+
+       // Send, extract and verify the first Invoice Request message
+       let onion_message = david.onion_messenger.next_onion_message_for_peer(bob_id).unwrap();
+       bob.onion_messenger.handle_onion_message(&david_id, &onion_message);
+
+       connect_peers(alice, charlie);
+
+       let onion_message = bob.onion_messenger.next_onion_message_for_peer(alice_id).unwrap();
+       alice.onion_messenger.handle_onion_message(&bob_id, &onion_message);
+
+       let (_, reply_path) = extract_invoice_request(alice, &onion_message);
+       assert_eq!(reply_path.introduction_node, IntroductionNode::NodeId(charlie_id));
+
+       // Send, extract and verify the second Invoice Request message
+       let onion_message = david.onion_messenger.next_onion_message_for_peer(bob_id).unwrap();
+       bob.onion_messenger.handle_onion_message(&david_id, &onion_message);
+
+       let onion_message = bob.onion_messenger.next_onion_message_for_peer(alice_id).unwrap();
+       alice.onion_messenger.handle_onion_message(&bob_id, &onion_message);
+
+       let (_, reply_path) = extract_invoice_request(alice, &onion_message);
+       assert_eq!(reply_path.introduction_node, IntroductionNode::NodeId(nodes[6].node.get_our_node_id()));
+}
+
+/// This test checks that when multiple potential introduction nodes are available for the payee,
+/// multiple `Invoice` messages are sent for the Refund, each with a different `reply_path`.
+#[test]
+fn send_invoice_for_refund_with_distinct_reply_path() {
+       let mut accept_forward_cfg = test_default_channel_config();
+       accept_forward_cfg.accept_forwards_to_priv_channels = true;
+
+       let mut features = channelmanager::provided_init_features(&accept_forward_cfg);
+       features.set_onion_messages_optional();
+       features.set_route_blinding_optional();
+
+       let chanmon_cfgs = create_chanmon_cfgs(7);
+       let node_cfgs = create_node_cfgs(7, &chanmon_cfgs);
+
+       *node_cfgs[1].override_init_features.borrow_mut() = Some(features);
+
+       let node_chanmgrs = create_node_chanmgrs(
+               7, &node_cfgs, &[None, Some(accept_forward_cfg), None, None, None, None, None]
+       );
+       let nodes = create_network(7, &node_cfgs, &node_chanmgrs);
+
+       create_unannounced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 1_000_000_000);
+       create_unannounced_chan_between_nodes_with_value(&nodes, 2, 3, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 1, 4, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 1, 5, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 2, 4, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 2, 5, 10_000_000, 1_000_000_000);
+
+       // Introduce another potential introduction node, node[6], as a candidate
+       create_unannounced_chan_between_nodes_with_value(&nodes, 3, 6, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 2, 6, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 4, 6, 10_000_000, 1_000_000_000);
+       create_announced_chan_between_nodes_with_value(&nodes, 5, 6, 10_000_000, 1_000_000_000);
+
+       let (alice, bob, charlie, david) = (&nodes[0], &nodes[1], &nodes[2], &nodes[3]);
+       let alice_id = alice.node.get_our_node_id();
+       let bob_id = bob.node.get_our_node_id();
+       let charlie_id = charlie.node.get_our_node_id();
+       let david_id = david.node.get_our_node_id();
+
+       disconnect_peers(alice, &[charlie, david, &nodes[4], &nodes[5], &nodes[6]]);
+       disconnect_peers(david, &[bob, &nodes[4], &nodes[5]]);
+
+       let absolute_expiry = Duration::from_secs(u64::MAX);
+       let payment_id = PaymentId([1; 32]);
+       let refund = alice.node
+               .create_refund_builder(10_000_000, absolute_expiry, payment_id, Retry::Attempts(0), None)
+               .unwrap()
+               .build().unwrap();
+       assert_ne!(refund.payer_id(), alice_id);
+       for path in refund.paths() {
+               assert_eq!(path.introduction_node, IntroductionNode::NodeId(bob_id));
+       }
+       expect_recent_payment!(alice, RecentPaymentDetails::AwaitingInvoice, payment_id);
+
+       let _expected_invoice = david.node.request_refund_payment(&refund).unwrap();
+
+       connect_peers(david, bob);
+
+       let onion_message = david.onion_messenger.next_onion_message_for_peer(bob_id).unwrap();
+       bob.onion_messenger.handle_onion_message(&david_id, &onion_message);
+
+       connect_peers(alice, charlie);
+
+       let onion_message = bob.onion_messenger.next_onion_message_for_peer(alice_id).unwrap();
+
+       let (_, reply_path) = extract_invoice(alice, &onion_message);
+       assert_eq!(reply_path.unwrap().introduction_node, IntroductionNode::NodeId(charlie_id));
+
+       // Send, extract and verify the second Invoice Request message
+       let onion_message = david.onion_messenger.next_onion_message_for_peer(bob_id).unwrap();
+       bob.onion_messenger.handle_onion_message(&david_id, &onion_message);
+
+       let onion_message = bob.onion_messenger.next_onion_message_for_peer(alice_id).unwrap();
+
+       let (_, reply_path) = extract_invoice(alice, &onion_message);
+       assert_eq!(reply_path.unwrap().introduction_node, IntroductionNode::NodeId(nodes[6].node.get_our_node_id()));
+}
+
 /// Checks that a deferred invoice can be paid asynchronously from an Event::InvoiceReceived.
 #[test]
 fn pays_bolt12_invoice_asynchronously() {