Added Upnp support behind a configuration option, moved the logic to the server code

config.go

@@ -47,6 +47,7 @@ const (
 	defaultRPCHost            = "localhost"
 	defaultMaxPendingChannels = 1
 	defaultNoEncryptWallet    = false
+	defaultUpnpSupport        = false
 	defaultTrickleDelay       = 30 * 1000
 	defaultMaxLogFiles        = 3
 	defaultMaxLogFileSize     = 10
@@ -195,6 +196,7 @@ type config struct {
 	UnsafeDisconnect   bool `long:"unsafe-disconnect" description:"Allows the rpcserver to intentionally disconnect from peers with open channels. USED FOR TESTING ONLY."`
 	UnsafeReplay       bool `long:"unsafe-replay" description:"Causes a link to replay the adds on its commitment txn after starting up, this enables testing of the sphinx replay logic."`
 	MaxPendingChannels int  `long:"maxpendingchannels" description:"The maximum number of incoming pending channels permitted per peer."`
+	UpnpSupport        bool `long:"upnpsupport" description:"Toggle Upnp support for auto network discovery"`
 
 	Bitcoin      *chainConfig    `group:"Bitcoin" namespace:"bitcoin"`
 	BtcdMode     *btcdConfig     `group:"btcd" namespace:"btcd"`
@@ -248,6 +250,7 @@ func loadConfig() (*config, error) {
 		LogDir:         defaultLogDir,
 		MaxLogFiles:    defaultMaxLogFiles,
 		MaxLogFileSize: defaultMaxLogFileSize,
+		UpnpSupport:    defaultUpnpSupport,
 		Bitcoin: &chainConfig{
 			MinHTLC:       defaultBitcoinMinHTLCMSat,
 			BaseFee:       defaultBitcoinBaseFeeMSat,

lnd.go

@@ -26,8 +26,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/NebulousLabs/go-upnp"
-
 	"gopkg.in/macaroon-bakery.v2/bakery"
 
 	"golang.org/x/net/context"
@@ -312,29 +310,6 @@ func lndMain() error {
 			"is proxying over Tor as well", cfg.Tor.StreamIsolation)
 	}
 
-	// Connect to router
-	d, err := upnp.Discover()
-	if err != nil {
-		fmt.Printf("Unable to discover router %v\n", err)
-		return err
-	}
-
-	// Get external IP
-	ip, err := d.ExternalIP()
-	if err != nil {
-		fmt.Printf("Unable to get external ip %v\n", err)
-		return err
-	}
-
-	ltndLog.Infof("Your external IP is: %s", ip)
-
-	// Forward peer port
-	err = d.Forward(uint16(cfg.PeerPort), "lnd pear port")
-	if err != nil {
-		fmt.Printf("Unable to forward pear port ip %v\n", err)
-		return err
-	}
-
 	// Set up the core server which will listen for incoming peer
 	// connections.
 	server, err := newServer(

server.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"context"
 	"crypto/rand"
 	"crypto/sha256"
 	"encoding/hex"
@@ -15,6 +16,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	upnp "github.com/NebulousLabs/go-upnp"
 	"github.com/coreos/bbolt"
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lightning-onion"
@@ -300,6 +302,38 @@ func newServer(listenAddrs []string, chanDB *channeldb.DB, cc *chainControl,
 		return nil, err
 	}
 
+	// Gather external IPs from config
+	externalIPs := cfg.ExternalIPs
+
+	if cfg.UpnpSupport {
+
+		// Connect to router
+		d, err := upnp.DiscoverCtx(context.Background())
+		if err != nil {
+			fmt.Printf("Upnp: Unable to discover router %v\n", err)
+			return nil, err
+		}
+
+		// Get external IP
+		ip, err := d.ExternalIP()
+		if err != nil {
+			fmt.Printf("Upnp: Unable to get external ip %v\n", err)
+			return nil, err
+		}
+
+		ltndLog.Infof("Your external IP is: %s", ip)
+
+		// Forward peer port
+		err = d.Forward(uint16(cfg.PeerPort), "lnd peer port")
+		if err != nil {
+			fmt.Printf("Upnp: Unable to forward pear port ip %v\n", err)
+			return nil, err
+		}
+
+		externalIPs = append(externalIPs, ip)
+
+	}
+
 	// If external IP addresses have been specified, add those to the list
 	// of this server's addresses.
 	selfAddrs := make([]net.Addr, 0, len(cfg.ExternalIPs))