Build Node Driver Registrar for Windows nodes

Signed-off-by: Deep Debroy <ddebroy@docker.com>

Dockerfile.Windows

@@ -0,0 +1,9 @@
+FROM mcr.microsoft.com/windows/servercore:1809 as core
+
+FROM mcr.microsoft.com/windows/nanoserver:1809
+LABEL description="CSI Node driver registrar"
+
+COPY ./bin/csi-node-driver-registrar.exe /csi-node-driver-registrar.exe
+COPY --from=core /Windows/System32/netapi32.dll /Windows/System32/netapi32.dll
+USER ContainerAdministrator
+ENTRYPOINT ["/csi-node-driver-registrar.exe"]

cmd/csi-node-driver-registrar/node_register.go

@@ -20,10 +20,10 @@ import (
 	"fmt"
 	"net"
 	"os"
+	"runtime"
 
 	"google.golang.org/grpc"
 
-	"golang.org/x/sys/unix"
 	"k8s.io/klog"
 	registerapi "k8s.io/kubernetes/pkg/kubelet/apis/pluginregistration/v1alpha1"
 )
@@ -48,16 +48,22 @@ func nodeRegister(
 		klog.Errorf("failed to stat the socket %s with error: %+v", socketPath, err)
 		os.Exit(1)
 	}
-	// Default to only user accessible socket, caller can open up later if desired
-	oldmask := unix.Umask(0077)
+
+	var oldmask int
+	if runtime.GOOS == "linux" {
+		// Default to only user accessible socket, caller can open up later if desired
+		oldmask, _ = umask(0077)
+	}
 
 	klog.Infof("Starting Registration Server at: %s\n", socketPath)
 	lis, err := net.Listen("unix", socketPath)
 	if err != nil {
 		klog.Errorf("failed to listen on socket: %s with error: %+v", socketPath, err)
 		os.Exit(1)
 	}
-	unix.Umask(oldmask)
+	if runtime.GOOS == "linux" {
+		umask(oldmask)
+	}
 	klog.Infof("Registration Server started at: %s\n", socketPath)
 	grpcServer := grpc.NewServer()
 	// Registers kubelet plugin watcher api.

cmd/csi-node-driver-registrar/util_linux.go

@@ -0,0 +1,27 @@
+// +build linux
+
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"golang.org/x/sys/unix"
+)
+
+func umask(mask int) (int, error) {
+	return unix.Umask(mask), nil
+}

cmd/csi-node-driver-registrar/util_windows.go

@@ -0,0 +1,27 @@
+// +build windows
+
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"errors"
+)
+
+func umask(mask int) (int, error) {
+	return -1, errors.New("umask not supported in Windows")
+}