Adds new constructor for setting up networks

This adds a new constructor, NewSetupNetworkHandler(string), which
allows for a networks namespace to be passed in

Signed-off-by: xibz <[email protected]>

Author: xibz

handlers.go

@@ -214,13 +214,15 @@ var CreateNetworkInterfacesHandler = Handler{
 	},
 }
 
-// SetupNetworkHandler is a named handler that will setup the network namespace
-// and network interface configuration prior to the Firecracker VMM starting.
-var SetupNetworkHandler = Handler{
-	Name: SetupNetworkHandlerName,
-	Fn: func(ctx context.Context, m *Machine) error {
-		return m.setupNetwork(ctx)
-	},
+// NewSetupNetworkHandler will construct a new handler that will setup a given
+// network with the provided netns
+func NewSetupNetworkHandler(netnsPath string) Handler {
+	return Handler{
+		Name: SetupNetworkHandlerName,
+		Fn: func(ctx context.Context, m *Machine) error {
+			return m.setupNetwork(ctx, netnsPath)
+		},
+	}
 }
 
 // SetupKernelArgsHandler is a named handler that will update any kernel boot
@@ -253,26 +255,28 @@ func NewSetMetadataHandler(metadata interface{}) Handler {
 	}
 }
 
-var defaultFcInitHandlerList = HandlerList{}.Append(
-	SetupNetworkHandler,
-	SetupKernelArgsHandler,
-	StartVMMHandler,
-	CreateLogFilesHandler,
-	BootstrapLoggingHandler,
-	CreateMachineHandler,
-	CreateBootSourceHandler,
-	AttachDrivesHandler,
-	CreateNetworkInterfacesHandler,
-	AddVsocksHandler,
-)
+func newDefaultFcInitHandlerList() HandlerList {
+	return HandlerList{}.Append(
+		NewSetupNetworkHandler(""),
+		SetupKernelArgsHandler,
+		StartVMMHandler,
+		CreateLogFilesHandler,
+		BootstrapLoggingHandler,
+		CreateMachineHandler,
+		CreateBootSourceHandler,
+		AttachDrivesHandler,
+		CreateNetworkInterfacesHandler,
+		AddVsocksHandler,
+	)
+}
 
 var defaultValidationHandlerList = HandlerList{}.Append(
 	NetworkConfigValidationHandler,
 )
 
 var defaultHandlers = Handlers{
 	Validation: defaultValidationHandlerList,
-	FcInit:     defaultFcInitHandlerList,
+	FcInit:     newDefaultFcInitHandlerList(),
 }
 
 // Handler represents a named handler that contains a name and a function which

jailer_test.go

@@ -145,7 +145,7 @@ func TestJail(t *testing.T) {
 		t.Run(c.name, func(t *testing.T) {
 			m := &Machine{
 				Handlers: Handlers{
-					FcInit: defaultFcInitHandlerList,
+					FcInit: newDefaultFcInitHandlerList(),
 				},
 			}
 			cfg := &Config{

machine.go

@@ -255,7 +255,6 @@ func NewMachine(ctx context.Context, cfg Config, opts ...Opt) (*Machine, error)
 	}
 
 	m.Handlers = defaultHandlers
-
 	if cfg.JailerCfg != nil {
 		m.Handlers.Validation = m.Handlers.Validation.Append(JailerConfigValidationHandler)
 		if err := jail(ctx, m, &cfg); err != nil {
@@ -268,10 +267,6 @@ func NewMachine(ctx context.Context, cfg Config, opts ...Opt) (*Machine, error)
 			Build(ctx)
 	}
 
-	for _, opt := range opts {
-		opt(m)
-	}
-
 	if m.logger == nil {
 		logger := log.New()
 		if cfg.Debug {
@@ -296,6 +291,12 @@ func NewMachine(ctx context.Context, cfg Config, opts ...Opt) (*Machine, error)
 	m.machineConfig = cfg.MachineCfg
 	m.Cfg = cfg
 
+	m.Handlers.FcInit = m.Handlers.FcInit.Swap(NewSetupNetworkHandler(m.netNSPath()))
+
+	for _, opt := range opts {
+		opt(m)
+	}
+
 	m.logger.Debug("Called NewMachine()")
 	return m, nil
 }
@@ -369,8 +370,8 @@ func (m *Machine) netNSPath() string {
 	return ""
 }
 
-func (m *Machine) setupNetwork(ctx context.Context) error {
-	err, cleanupFuncs := m.Cfg.NetworkInterfaces.setupNetwork(ctx, m.Cfg.VMID, m.netNSPath(), m.logger)
+func (m *Machine) setupNetwork(ctx context.Context, netnsPath string) error {
+	err, cleanupFuncs := m.Cfg.NetworkInterfaces.setupNetwork(ctx, m.Cfg.VMID, netnsPath, m.logger)
 	m.cleanupFuncs = append(m.cleanupFuncs, cleanupFuncs...)
 	return err
 }