invoice: don't allow payments in expired invoices.

Fixes: #363
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lightningd/invoice.c

@@ -15,6 +15,7 @@ struct invoice_waiter {
 	struct command *cmd;
 };
 
+/* FIXME: remove this, just use database ops. */
 struct invoices {
 	/* Payments for r values we know about. */
 	struct list_head invlist;
@@ -27,9 +28,12 @@ struct invoice *find_unpaid(struct invoices *invs, const struct sha256 *rhash)
 	struct invoice *i;
 
 	list_for_each(&invs->invlist, i, list) {
-		if (structeq(rhash, &i->rhash) && i->state == UNPAID)
+		if (structeq(rhash, &i->rhash) && i->state == UNPAID) {
+			if (time_now().ts.tv_sec > i->expiry_time)
+				break;
 			return i;
 		}
+	}
 	return NULL;
 }
 

tests/test_lightningd.py

@@ -314,6 +314,24 @@ class LightningDTests(BaseLightningDTests):
         assert b11['expiry'] == 3600
         assert b11['payee'] == l1.info['id']
 
+    def test_invoice_expiry(self):
+        l1,l2 = self.connect()
+
+        chanid = self.fund_channel(l1, l2, 10**6)
+
+        # Wait for route propagation.
+        bitcoind.rpc.generate(5)
+        l1.daemon.wait_for_logs(['Received channel_update for channel {}\(0\)'
+                                 .format(chanid),
+                                'Received channel_update for channel {}\(1\)'
+                                 .format(chanid)])
+
+        inv = l2.rpc.invoice(123000, 'test_pay', 'description', 1)['bolt11']
+        time.sleep(2)
+        self.assertRaises(ValueError, l1.rpc.pay, inv)
+        assert l2.rpc.listinvoice('test_pay')[0]['complete'] == False
+        assert l2.rpc.listinvoice('test_pay')[0]['expiry_time'] < time.time()
+
     def test_connect(self):
         l1,l2 = self.connect()