From 34fd27280ad71b830dd031e01fac32645a28e409 Mon Sep 17 00:00:00 2001
From: Conner Fromknecht <conner@lightning.engineering>
Date: Mon, 16 Dec 2019 13:06:59 -0800
Subject: [PATCH] peer: validate remote peer's feature deps

---
 peer.go | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/peer.go b/peer.go
index be8a1d26b..53092edbd 100644
--- a/peer.go
+++ b/peer.go
@@ -22,6 +22,7 @@ import (
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/contractcourt"
+	"github.com/lightningnetwork/lnd/feature"
 	"github.com/lightningnetwork/lnd/htlcswitch"
 	"github.com/lightningnetwork/lnd/lnpeer"
 	"github.com/lightningnetwork/lnd/lnwallet"
@@ -2476,6 +2477,14 @@ func (p *peer) handleInitMsg(msg *lnwire.Init) error {
 		return err
 	}
 
+	// Ensure the remote party's feature vector contains all transistive
+	// dependencies. We know ours are are correct since they are validated
+	// during the feature manager's instantiation.
+	err = feature.ValidateDeps(p.remoteFeatures)
+	if err != nil {
+		return fmt.Errorf("peer set invalid feature vector: %v", err)
+	}
+
 	// Now that we know we understand their requirements, we'll check to
 	// see if they don't support anything that we deem to be mandatory.
 	switch {