From c9afa9f5ef7b8567bb086624aca90fb00b9cc26b Mon Sep 17 00:00:00 2001
From: Steve Fan <29133953+stevefan1999-personal@users.noreply.github.com>
Date: Mon, 27 Jul 2020 21:02:11 +0800
Subject: [PATCH] add initial advertise(Addr|Port) support

(cherry picked from commit 2a0b4f335eb54caa19ad908cdc441d73b57d68ca)
---
 cluster/cluster.go | 5 +++--
 config.go          | 5 +++++
 main.go            | 2 +-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/cluster/cluster.go b/cluster/cluster.go
index c5e1b2f..be6bbd1 100644
--- a/cluster/cluster.go
+++ b/cluster/cluster.go
@@ -31,7 +31,7 @@ type Cluster struct {
 
 // New is used to create a new Cluster instance
 // The returned instance is ready to be updated with the local node settings then joined
-func New(name string, init bool, clusterKey []byte, bindAddr string, bindPort int, useIPAsName bool) (*Cluster, error) {
+func New(name string, init bool, clusterKey []byte, bindAddr string, bindPort int, advertiseAddr string, advertisePort int, useIPAsName bool) (*Cluster, error) {
 	state := &state{}
 	if !init {
 		loadState(state, name)
@@ -47,7 +47,8 @@ func New(name string, init bool, clusterKey []byte, bindAddr string, bindPort in
 	mlConfig.SecretKey = clusterKey
 	mlConfig.BindAddr = bindAddr
 	mlConfig.BindPort = bindPort
-	mlConfig.AdvertisePort = bindPort
+	mlConfig.AdvertiseAddr = advertiseAddr
+	mlConfig.AdvertisePort = advertisePort
 	if useIPAsName && bindAddr != "0.0.0.0" {
 		mlConfig.Name = bindAddr
 	}
diff --git a/config.go b/config.go
index 34528c3..2c14489 100644
--- a/config.go
+++ b/config.go
@@ -17,6 +17,7 @@ type config struct {
 	Init              bool     `desc:"whether to explicitly (re)initialize the cluster; any known state from previous runs will be forgotten"`
 	BindAddr          string   `id:"bind-addr" desc:"IP address to bind to for cluster membership traffic (cannot be used with --bind-iface)"`
 	BindIface         string   `id:"bind-iface" desc:"Interface to bind to for cluster membership traffic (cannot be used with --bind-addr)"`
+	AdvertiseAddr     string   `id:"advertise-addr" desc:"IP address to advertise to other nodes for NAT traversal"`
 	ClusterPort       int      `id:"cluster-port" desc:"port used for membership gossip traffic (both TCP and UDP); must be the same across cluster" default:"7946"`
 	WireguardPort     int      `id:"wireguard-port" desc:"port used for wireguard traffic (UDP); must be the same across cluster" default:"51820"`
 	BaseMtu           int      `id:"mtu" desc:"MTU of the underlying network, taking intermediary hops into account" default:"1500"`
@@ -80,6 +81,10 @@ func loadConfig() (*config, error) {
 		}
 	}
 
+	if config.AdvertiseAddr == "" {
+		config.AdvertiseAddr = config.BindAddr
+	}
+
 	return &config, nil
 }
 
diff --git a/main.go b/main.go
index 28c8fd3..86ddb41 100644
--- a/main.go
+++ b/main.go
@@ -35,7 +35,7 @@ func main() {
 	logrus.SetLevel(logLevel)
 
 	// Create the wireguard and cluster configuration
-	cluster, err := cluster.New(config.Interface, config.Init, config.ClusterKey, config.BindAddr, config.ClusterPort, config.UseIPAsName)
+	cluster, err := cluster.New(config.Interface, config.Init, config.ClusterKey, config.BindAddr, config.ClusterPort, config.AdvertiseAddr, config.ClusterPort, config.UseIPAsName)
 	if err != nil {
 		logrus.WithError(err).Fatal("could not create cluster")
 	}