Support for com.docker.network.bridge.container_interface_prefix label

Signed-off-by: Wolfgang Nagele <mail@wnagele.com>

drivers/bridge/bridge.go

@@ -31,7 +31,7 @@ const (
 	networkType                = "bridge"
 	vethPrefix                 = "veth"
 	vethLen                    = 7
-	containerVethPrefix     = "eth"
+	defaultContainerVethPrefix = "eth"
 	maxAllocatePortAttempts    = 10
 )
 
@@ -63,6 +63,7 @@ type networkConfiguration struct {
 	Mtu                  int
 	DefaultBindingIP     net.IP
 	DefaultBridge        bool
+	ContainerIfacePrefix string
 	// Internal fields set after ipam data parsing
 	AddressIPv4        *net.IPNet
 	AddressIPv6        *net.IPNet
@@ -239,6 +240,8 @@ func (c *networkConfiguration) fromLabels(labels map[string]string) error {
 			if c.DefaultBindingIP = net.ParseIP(value); c.DefaultBindingIP == nil {
 				return parseErr(label, value, "nil ip")
 			}
+		case netlabel.ContainerIfacePrefix:
+			c.ContainerIfacePrefix = value
 		}
 	}
 
@@ -1217,6 +1220,10 @@ func (d *driver) Join(nid, eid string, sboxKey string, jinfo driverapi.JoinInfo,
 	}
 
 	iNames := jinfo.InterfaceName()
+	containerVethPrefix := defaultContainerVethPrefix
+	if network.config.ContainerIfacePrefix != "" {
+		containerVethPrefix = network.config.ContainerIfacePrefix
+	}
 	err = iNames.SetNames(endpoint.srcName, containerVethPrefix)
 	if err != nil {
 		return err

drivers/bridge/bridge_store.go

@@ -143,6 +143,7 @@ func (ncfg *networkConfiguration) MarshalJSON() ([]byte, error) {
 	nMap["DefaultBindingIP"] = ncfg.DefaultBindingIP.String()
 	nMap["DefaultGatewayIPv4"] = ncfg.DefaultGatewayIPv4.String()
 	nMap["DefaultGatewayIPv6"] = ncfg.DefaultGatewayIPv6.String()
+	nMap["ContainerIfacePrefix"] = ncfg.ContainerIfacePrefix
 	nMap["BridgeIfaceCreator"] = ncfg.BridgeIfaceCreator
 
 	if ncfg.AddressIPv4 != nil {
@@ -178,6 +179,10 @@ func (ncfg *networkConfiguration) UnmarshalJSON(b []byte) error {
 		}
 	}
 
+	if v, ok := nMap["ContainerIfacePrefix"]; ok {
+		ncfg.ContainerIfacePrefix = v.(string)
+	}
+
 	ncfg.DefaultBridge = nMap["DefaultBridge"].(bool)
 	ncfg.DefaultBindingIP = net.ParseIP(nMap["DefaultBindingIP"].(string))
 	ncfg.DefaultGatewayIPv4 = net.ParseIP(nMap["DefaultGatewayIPv4"].(string))

netlabel/labels.go

@@ -50,6 +50,9 @@ const (
 
 	// Internal constant represents that the network is internal which disables default gateway service
 	Internal = Prefix + ".internal"
+
+	// ContainerIfacePrefix can be used to override the interface prefix used inside the container
+	ContainerIfacePrefix = Prefix + ".container_iface_prefix"
 )
 
 var (

osl/interface_linux.go

@@ -241,8 +241,8 @@ func (n *networkNamespace) AddInterface(srcName, dstPrefix string, options ...If
 	if n.isDefault {
 		i.dstName = i.srcName
 	} else {
-		i.dstName = fmt.Sprintf("%s%d", i.dstName, n.nextIfIndex)
-		n.nextIfIndex++
+		i.dstName = fmt.Sprintf("%s%d", dstPrefix, n.nextIfIndex[dstPrefix])
+		n.nextIfIndex[dstPrefix]++
 	}
 
 	path := n.path

osl/namespace_linux.go

@@ -48,7 +48,7 @@ type networkNamespace struct {
 	gwv6         net.IP
 	staticRoutes []*types.StaticRoute
 	neighbors    []*neigh
-	nextIfIndex  int
+	nextIfIndex  map[string]int
 	isDefault    bool
 	nlHandle     *netlink.Handle
 	loV6Enabled  bool
@@ -203,7 +203,7 @@ func NewSandbox(key string, osCreate, isRestore bool) (Sandbox, error) {
 		once.Do(createBasePath)
 	}
 
-	n := &networkNamespace{path: key, isDefault: !osCreate}
+	n := &networkNamespace{path: key, isDefault: !osCreate, nextIfIndex: make(map[string]int)}
 
 	sboxNs, err := netns.GetFromPath(n.path)
 	if err != nil {
@@ -256,7 +256,7 @@ func GetSandboxForExternalKey(basePath string, key string) (Sandbox, error) {
 	if err := mountNetworkNamespace(basePath, key); err != nil {
 		return nil, err
 	}
-	n := &networkNamespace{path: key}
+	n := &networkNamespace{path: key, nextIfIndex: make(map[string]int)}
 
 	sboxNs, err := netns.GetFromPath(n.path)
 	if err != nil {
@@ -495,8 +495,8 @@ func (n *networkNamespace) Restore(ifsopt map[string][]IfaceOption, routes []*ty
 			}
 			index++
 			n.Lock()
-			if index > n.nextIfIndex {
-				n.nextIfIndex = index
+			if index > n.nextIfIndex[dstPrefix] {
+				n.nextIfIndex[dstPrefix] = index
 			}
 			n.iFaces = append(n.iFaces, i)
 			n.Unlock()