f Fail duplicate inbound payments

Author: tnull

src/event.rs

@@ -295,6 +295,22 @@ where
 				via_channel_id: _,
 				via_user_channel_id: _,
 			} => {
+				if let Some(info) = self.payment_store.get(&payment_hash) {
+					if info.status == PaymentStatus::Succeeded {
+						log_info!(
+							self.logger,
+							"Refused duplicate inbound payment from payment hash {} of {}msat",
+							hex_utils::to_string(&payment_hash.0),
+							amount_msat,
+						);
+						self.channel_manager.fail_htlc_backwards(&payment_hash);
+						self.payment_store
+							.set_status(&payment_hash, PaymentStatus::Failed)
+							.expect("Failed to access payment store");
+						return;
+					}
+				}
+
 				log_info!(
 					self.logger,
 					"Received payment from payment hash {} of {}msat",

src/tests/functional_tests.rs

@@ -197,13 +197,23 @@ fn channel_full_cycle() {
 	};
 
 	println!("\nB receive_payment");
-	let invoice = node_b.receive_payment(1000000, &"asdf", 9217).unwrap();
+	let invoice_amount = 1000000;
+	let invoice = node_b.receive_payment(invoice_amount, &"asdf", 9217).unwrap();
 
 	println!("\nA send_payment");
-	node_a.send_payment(invoice).unwrap();
+	let payment_hash = node_a.send_payment(invoice.clone()).unwrap();
 
 	expect_event!(node_a, PaymentSuccessful);
 	expect_event!(node_b, PaymentReceived);
+	assert_eq!(node_a.payment_info(&payment_hash).unwrap().status, PaymentStatus::Succeeded);
+	assert_eq!(node_a.payment_info(&payment_hash).unwrap().direction, PaymentDirection::Outbound);
+	assert_eq!(node_a.payment_info(&payment_hash).unwrap().amount_msat, Some(invoice_amount));
+	assert_eq!(node_b.payment_info(&payment_hash).unwrap().status, PaymentStatus::Succeeded);
+	assert_eq!(node_b.payment_info(&payment_hash).unwrap().direction, PaymentDirection::Inbound);
+	assert_eq!(node_b.payment_info(&payment_hash).unwrap().amount_msat, Some(invoice_amount));
+
+	// Assert we fail duplicate outbound payments.
+	assert_eq!(Err(Error::NonUniquePaymentHash), node_a.send_payment(invoice));
 
 	// Test under-/overpayment
 	let invoice_amount = 1000000;