Check for invoice expiry in InvoicePayer before we send any HTLCs

Author: TheBlueMatt

lightning-invoice/src/payment.rs

@@ -257,6 +257,10 @@ where
 						final_value_msat: invoice.amount_milli_satoshis().or(amount_msats).unwrap(),
 						final_cltv_expiry_delta: invoice.min_final_cltv_expiry() as u32,
 					};
+					if has_expired(&params) {
+						log_trace!(self.logger, "Invoice expired prior to first send for payment {}", log_bytes!(payment_hash.0));
+						return Err(PaymentError::Invoice("Invoice expired prior to send"));
+					}
 					let first_hops = self.payer.first_hops();
 					let route = self.router.find_route(
 						&payer,
@@ -505,6 +509,25 @@ mod tests {
 			.unwrap()
 	}
 
+	fn will_expire_in_1_sec_invoice(payment_preimage: PaymentPreimage) -> Invoice {
+		let payment_hash = Sha256::hash(&payment_preimage.0);
+		let private_key = SecretKey::from_slice(&[42; 32]).unwrap();
+		let timestamp = SystemTime::now()
+			.checked_sub(Duration::from_secs(DEFAULT_EXPIRY_TIME - 1))
+			.unwrap();
+		InvoiceBuilder::new(Currency::Bitcoin)
+			.description("test".into())
+			.payment_hash(payment_hash)
+			.payment_secret(PaymentSecret([0; 32]))
+			.timestamp(timestamp)
+			.min_final_cltv_expiry(144)
+			.amount_milli_satoshis(128)
+			.build_signed(|hash| {
+				Secp256k1::new().sign_recoverable(hash, &private_key)
+			})
+			.unwrap()
+	}
+
 	#[test]
 	fn pays_invoice_on_first_attempt() {
 		let event_handled = core::cell::RefCell::new(false);
@@ -720,7 +743,26 @@ mod tests {
 
 		let payment_preimage = PaymentPreimage([1; 32]);
 		let invoice = expired_invoice(payment_preimage);
+		if let PaymentError::Invoice(msg) = invoice_payer.pay_invoice(&invoice).unwrap_err() {
+			assert_eq!(msg, "Invoice expired prior to send");
+		} else { panic!("Expected Invoice Error"); }
+	}
+
+	#[test]
+	fn fails_retrying_invoice_after_expiration() {
+		let event_handled = core::cell::RefCell::new(false);
+		let event_handler = |_: &_| { *event_handled.borrow_mut() = true; };
+
+		let payer = TestPayer::new();
+		let router = TestRouter {};
+		let logger = TestLogger::new();
+		let invoice_payer =
+			InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2));
+
+		let payment_preimage = PaymentPreimage([1; 32]);
+		let invoice = will_expire_in_1_sec_invoice(payment_preimage);
 		let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap());
+		std::thread::sleep(Duration::from_secs(2));
 		assert_eq!(*payer.attempts.borrow(), 1);
 
 		let event = Event::PaymentPathFailed {