Honor user provided listen address for gossip

If user provided a non-zero listen address, honor that and bind only to
that address. Right now it is not honored and we always bind to all ip
addresses in the host.

Signed-off-by: Jana Radhakrishnan <mrjana@docker.com>

Author: mrjana

agent.go

@@ -172,10 +172,12 @@ func (c *controller) agentSetup() error {
 	advAddr := clusterProvider.GetAdvertiseAddress()
 	remote := clusterProvider.GetRemoteAddress()
 	remoteAddr, _, _ := net.SplitHostPort(remote)
+	listen := clusterProvider.GetListenAddress()
+	listenAddr, _, _ := net.SplitHostPort(listen)
 
-	logrus.Infof("Initializing Libnetwork Agent Local-addr=%s Adv-addr=%s Remote-addr =%s", bindAddr, advAddr, remoteAddr)
+	logrus.Infof("Initializing Libnetwork Agent Listen-Addr=%s Local-addr=%s Adv-addr=%s Remote-addr =%s", listenAddr, bindAddr, advAddr, remoteAddr)
 	if advAddr != "" && c.agent == nil {
-		if err := c.agentInit(bindAddr, advAddr); err != nil {
+		if err := c.agentInit(listenAddr, bindAddr, advAddr); err != nil {
 			logrus.Errorf("Error in agentInit : %v", err)
 		} else {
 			c.drvRegistry.WalkDrivers(func(name string, driver driverapi.Driver, capability driverapi.Capability) bool {
@@ -236,7 +238,7 @@ func (c *controller) getPrimaryKeyTag(subsys string) ([]byte, uint64, error) {
 	return keys[1].Key, keys[1].LamportTime, nil
 }
 
-func (c *controller) agentInit(bindAddrOrInterface, advertiseAddr string) error {
+func (c *controller) agentInit(listenAddr, bindAddrOrInterface, advertiseAddr string) error {
 	if !c.isAgent() {
 		return nil
 	}
@@ -252,6 +254,7 @@ func (c *controller) agentInit(bindAddrOrInterface, advertiseAddr string) error
 	logrus.Info("Gossip cluster hostname ", nodeName)
 
 	nDB, err := networkdb.New(&networkdb.Config{
+		BindAddr:      listenAddr,
 		AdvertiseAddr: advertiseAddr,
 		NodeName:      nodeName,
 		Keys:          keys,

cluster/provider.go

@@ -10,6 +10,7 @@ type Provider interface {
 	IsManager() bool
 	IsAgent() bool
 	GetLocalAddress() string
+	GetListenAddress() string
 	GetAdvertiseAddress() string
 	GetRemoteAddress() string
 	ListenClusterEvents() <-chan struct{}

cmd/dnet/dnet.go

@@ -316,6 +316,10 @@ func (d *dnetConnection) GetLocalAddress() string {
 	return d.Orchestration.Bind
 }
 
+func (d *dnetConnection) GetListenAddress() string {
+	return d.Orchestration.Bind
+}
+
 func (d *dnetConnection) GetRemoteAddress() string {
 	return d.Orchestration.Peer
 }

networkdb/cluster.go

@@ -86,6 +86,7 @@ func (nDB *NetworkDB) RemoveKey(key []byte) {
 func (nDB *NetworkDB) clusterInit() error {
 	config := memberlist.DefaultLANConfig()
 	config.Name = nDB.config.NodeName
+	config.BindAddr = nDB.config.BindAddr
 	config.AdvertiseAddr = nDB.config.AdvertiseAddr
 
 	if nDB.config.BindPort != 0 {

networkdb/networkdb.go

@@ -121,6 +121,10 @@ type Config struct {
 	// NodeName is the cluster wide unique name for this node.
 	NodeName string
 
+	// BindAddr is the IP on which networkdb listens. It can be
+	// 0.0.0.0 to listen on all addresses on the host.
+	BindAddr string
+
 	// AdvertiseAddr is the node's IP address that we advertise for
 	// cluster communication.
 	AdvertiseAddr string