Add internal network option

Signed-off-by: Chun Chen <ramichen@tencent.com>

libnetwork/default_gateway.go

@@ -103,6 +103,9 @@ func (sb *sandbox) needDefaultGW() bool {
 		if ep.getNetwork().Type() == "null" || ep.getNetwork().Type() == "host" {
 			continue
 		}
+		if ep.getNetwork().Internal() {
+			return false
+		}
 		if ep.joinInfo.disableGatewayService {
 			return false
 		}

libnetwork/drivers/bridge/bridge.go

@@ -490,6 +490,12 @@ func parseNetworkOptions(id string, option options.Generic) (*networkConfigurati
 		config.EnableIPv6 = val.(bool)
 	}
 
+	if val, ok := option[netlabel.Internal]; ok {
+		if internal, ok := val.(bool); ok && internal {
+			return nil, &driverapi.ErrNotImplemented{}
+		}
+	}
+
 	// Finally validate the configuration
 	if err = config.Validate(); err != nil {
 		return nil, err

libnetwork/libnetwork_test.go

@@ -2327,3 +2327,10 @@ func TestParallel2(t *testing.T) {
 func TestParallel3(t *testing.T) {
 	runParallelTests(t, 3)
 }
+
+func TestNetworkInternal(t *testing.T) {
+	_, err := controller.NewNetwork(bridgeNetType, "testnetworkinternal", libnetwork.NetworkOptionInternalNetwork())
+	if err == nil || err.Error() != (&driverapi.ErrNotImplemented{}).Error() {
+		t.Fatal("bridge network can't be internal")
+	}
+}

libnetwork/netlabel/labels.go

@@ -41,6 +41,9 @@ const (
 
 	// Gateway represents the gateway for the network
 	Gateway = Prefix + ".gateway"
+
+	// Internal constant represents that the network is internal which disables default gateway service
+	Internal = Prefix + ".internal"
 )
 
 var (

libnetwork/network.go

@@ -163,6 +163,7 @@ type network struct {
 	persist      bool
 	stopWatchCh  chan struct{}
 	drvOnce      *sync.Once
+	internal     bool
 	sync.Mutex
 }
 
@@ -305,6 +306,7 @@ func (n *network) CopyTo(o datastore.KVObject) error {
 	dstN.dbIndex = n.dbIndex
 	dstN.dbExists = n.dbExists
 	dstN.drvOnce = n.drvOnce
+	dstN.internal = n.internal
 
 	for _, v4conf := range n.ipamV4Config {
 		dstV4Conf := &IpamConf{}
@@ -391,6 +393,7 @@ func (n *network) MarshalJSON() ([]byte, error) {
 		}
 		netMap["ipamV6Info"] = string(iis)
 	}
+	netMap["internal"] = n.internal
 	return json.Marshal(netMap)
 }
 
@@ -454,6 +457,9 @@ func (n *network) UnmarshalJSON(b []byte) (err error) {
 			return err
 		}
 	}
+	if v, ok := netMap["internal"]; ok {
+		n.internal = v.(bool)
+	}
 	return nil
 }
 
@@ -480,6 +486,18 @@ func NetworkOptionPersist(persist bool) NetworkOption {
 	}
 }
 
+// NetworkOptionInternalNetwork returns an option setter to config the network
+// to be internal which disables default gateway service
+func NetworkOptionInternalNetwork() NetworkOption {
+	return func(n *network) {
+		n.internal = true
+		if n.generic == nil {
+			n.generic = make(map[string]interface{})
+		}
+		n.generic[netlabel.Internal] = true
+	}
+}
+
 // NetworkOptionIpam function returns an option setter for the ipam configuration for this network
 func NetworkOptionIpam(ipamDriver string, addrSpace string, ipV4 []*IpamConf, ipV6 []*IpamConf) NetworkOption {
 	return func(n *network) {
@@ -1187,3 +1205,10 @@ func (n *network) IpamInfo() ([]*IpamInfo, []*IpamInfo) {
 
 	return v4Info, v6Info
 }
+
+func (n *network) Internal() bool {
+	n.Lock()
+	defer n.Unlock()
+
+	return n.internal
+}