From f868bc128b412876b08880b716c5ffb2be69d4de Mon Sep 17 00:00:00 2001
From: Conner Fromknecht <conner@lightning.engineering>
Date: Wed, 18 Dec 2019 23:56:59 -0800
Subject: [PATCH] rpcserver+routerrpc: thread features + payment addr to
 SendPayment

---
 lnrpc/routerrpc/router_backend.go |  2 ++
 routing/payment_session.go        |  9 ++++++---
 routing/router.go                 | 13 +++++++++++++
 rpcserver.go                      |  6 ++++++
 4 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/lnrpc/routerrpc/router_backend.go b/lnrpc/routerrpc/router_backend.go
index 7722a3c8..383180a3 100644
--- a/lnrpc/routerrpc/router_backend.go
+++ b/lnrpc/routerrpc/router_backend.go
@@ -602,6 +602,8 @@ func (r *RouterBackend) extractIntentFromSendRequest(
 		payIntent.RouteHints = append(
 			payIntent.RouteHints, payReq.RouteHints...,
 		)
+		payIntent.DestFeatures = payReq.Features
+		payIntent.PaymentAddr = payReq.PaymentAddr
 	} else {
 		// Otherwise, If the payment request field was not specified
 		// (and a custom route wasn't specified), construct the payment
diff --git a/routing/payment_session.go b/routing/payment_session.go
index d8e765f1..e5474ddf 100644
--- a/routing/payment_session.go
+++ b/routing/payment_session.go
@@ -98,6 +98,8 @@ func (p *paymentSession) RequestRoute(payment *LightningPayment,
 		LastHop:           payment.LastHop,
 		CltvLimit:         cltvLimit,
 		DestCustomRecords: payment.DestCustomRecords,
+		DestFeatures:      payment.DestFeatures,
+		PaymentAddr:       payment.PaymentAddr,
 	}
 
 	// We'll also obtain a set of bandwidthHints from the lower layer for
@@ -131,9 +133,10 @@ func (p *paymentSession) RequestRoute(payment *LightningPayment,
 	route, err := newRoute(
 		sourceVertex, path, height,
 		finalHopParams{
-			amt:       payment.Amount,
-			cltvDelta: finalCltvDelta,
-			records:   payment.DestCustomRecords,
+			amt:         payment.Amount,
+			cltvDelta:   finalCltvDelta,
+			records:     payment.DestCustomRecords,
+			paymentAddr: payment.PaymentAddr,
 		},
 	)
 	if err != nil {
diff --git a/routing/router.go b/routing/router.go
index e8b42173..ef38788d 100644
--- a/routing/router.go
+++ b/routing/router.go
@@ -1601,6 +1601,19 @@ type LightningPayment struct {
 	// is reached. If nil, any node may be used.
 	LastHop *route.Vertex
 
+	// DestFeatures specifies the set of features we assume the final node
+	// has for pathfinding. Typically these will be taken directly from an
+	// invoice, but they can also be manually supplied or assumed by the
+	// sender. If a nil feature vector is provided, the router will try to
+	// fallback to the graph in order to load a feature vector for a node in
+	// the public graph.
+	DestFeatures *lnwire.FeatureVector
+
+	// PaymentAddr is the payment address specified by the receiver. This
+	// field should be a random 32-byte nonce presented in the receiver's
+	// invoice to prevent probing of the destination.
+	PaymentAddr *[32]byte
+
 	// PaymentRequest is an optional payment request that this payment is
 	// attempting to complete.
 	PaymentRequest []byte
diff --git a/rpcserver.go b/rpcserver.go
index b016ca98..1e5e71b1 100644
--- a/rpcserver.go
+++ b/rpcserver.go
@@ -3241,6 +3241,8 @@ type rpcPaymentIntent struct {
 	routeHints        [][]zpay32.HopHint
 	outgoingChannelID *uint64
 	lastHop           *route.Vertex
+	destFeatures      *lnwire.FeatureVector
+	paymentAddr       *[32]byte
 	payReq            []byte
 
 	destCustomRecords record.CustomSet
@@ -3370,6 +3372,8 @@ func (r *rpcServer) extractPaymentIntent(rpcPayReq *rpcPaymentRequest) (rpcPayme
 		payIntent.cltvDelta = uint16(payReq.MinFinalCLTVExpiry())
 		payIntent.routeHints = payReq.RouteHints
 		payIntent.payReq = []byte(rpcPayReq.PaymentRequest)
+		payIntent.destFeatures = payReq.Features
+		payIntent.paymentAddr = payReq.PaymentAddr
 
 		if err := validateDest(payIntent.dest); err != nil {
 			return payIntent, err
@@ -3492,6 +3496,8 @@ func (r *rpcServer) dispatchPaymentIntent(
 			PaymentRequest:    payIntent.payReq,
 			PayAttemptTimeout: routing.DefaultPayAttemptTimeout,
 			DestCustomRecords: payIntent.destCustomRecords,
+			DestFeatures:      payIntent.destFeatures,
+			PaymentAddr:       payIntent.paymentAddr,
 		}
 
 		preImage, route, routerErr = r.server.chanRouter.SendPayment(