itest: add interceptor wire records access test

itest/list_on_test.go

@@ -426,6 +426,10 @@ var allTestCases = []*lntest.TestCase{
  Name: "forward interceptor modified htlc",
  TestFunc: testForwardInterceptorModifiedHtlc,
  },
+ {
+ Name: "forward interceptor wire records",
+ TestFunc: testForwardInterceptorWireRecords,
+ },
  {
  Name: "zero conf channel open",
  TestFunc: testZeroConfChannelOpen,

itest/lnd_forward_interceptor_test.go

@@ -479,6 +479,78 @@ func testForwardInterceptorModifiedHtlc(ht *lntest.HarnessTest) {
  ht.CloseChannel(bob, cpBC)
 }
 
+func testForwardInterceptorWireRecords(ht *lntest.HarnessTest) {
+ // Initialize the test context with 3 connected nodes.
+ ts := newInterceptorTestScenario(ht)
+
+ alice, bob, carol := ts.alice, ts.bob, ts.carol
+
+ // Open and wait for channels.
+ const chanAmt = btcutil.Amount(300000)
+ p := lntest.OpenChannelParams{Amt: chanAmt}
+ reqs := []*lntest.OpenChannelRequest{
+ {Local: alice, Remote: bob, Param: p},
+ {Local: bob, Remote: carol, Param: p},
+ }
+ resp := ht.OpenMultiChannelsAsync(reqs)
+ cpAB, cpBC := resp[0], resp[1]
+
+ // Make sure Alice is aware of channel Bob=>Carol.
+ ht.AssertTopologyChannelOpen(alice, cpBC)
+
+ // Connect an interceptor to Bob's node.
+ bobInterceptor, cancelBobInterceptor := bob.RPC.HtlcInterceptor()
+
+ req := &lnrpc.Invoice{ValueMsat: 1000}
+ addResponse := carol.RPC.AddInvoice(req)
+ invoice := carol.RPC.LookupInvoice(addResponse.RHash)
+
+ sendReq := &routerrpc.SendPaymentRequest{
+ PaymentRequest: invoice.PaymentRequest,
+ TimeoutSeconds: int32(wait.PaymentTimeout.Seconds()),
+ FeeLimitMsat: noFeeLimitMsat,
+ FirstHopCustomRecords: map[uint64][]byte{
+ 65537: []byte("test"),
+ },
+ }
+
+ _ = alice.RPC.SendPayment(sendReq)
+
+ // We start the htlc interceptor with a simple implementation that saves
+ // all intercepted packets. These packets are held to simulate a
+ // pending payment.
+ packet := ht.ReceiveHtlcInterceptor(bobInterceptor)
+
+ require.Len(ht, packet.WireCustomRecords, 1)
+
+ val, ok := packet.WireCustomRecords[65537]
+ require.True(ht, ok, "expected custom record")
+ require.Equal(ht, []byte("test"), val)
+
+ action := routerrpc.ResolveHoldForwardAction_RESUME_MODIFIED
+ newOutgoingAmountMsat := packet.OutgoingAmountMsat + 800
+
+ err := bobInterceptor.Send(&routerrpc.ForwardHtlcInterceptResponse{
+ IncomingCircuitKey: packet.IncomingCircuitKey,
+ OutgoingAmountMsat: newOutgoingAmountMsat,
+ Action: action,
+ })
+ require.NoError(ht, err, "failed to send request")
+
+ // Cancel the context, which will disconnect Bob's interceptor.
+ cancelBobInterceptor()
+
+ // Assert that the payment was successful.
+ var preimage lntypes.Preimage
+ copy(preimage[:], invoice.RPreimage)
+ ht.AssertPaymentStatus(alice, preimage, lnrpc.Payment_SUCCEEDED)
+
+ // Finally, close channels.
+ ht.CloseChannel(alice, cpAB)
+ ht.CloseChannel(bob, cpBC)
+
+}
+
 // interceptorTestScenario is a helper struct to hold the test context and
 // provide the needed functionality.
 type interceptorTestScenario struct {