add CIFS/SMB based file sharing for windows

it allows users to mount the host's home folder at
/mnt/c/users/$username directory in the crc vm

to determine if folder sharing is supported/enabled it
checks that a smb share named 'crc-dir0' exists which
should've been created during msi installation

since CIFS/SMB is a network file system and needs a username
and password for getting access two new fields 'SharedDirUsername'
and 'SharedDirPassword' is added to the MachineConfig and StartConfig
structs

Author: anjannath

pkg/crc/machine/config/config.go

@@ -7,15 +7,17 @@ type MachineConfig struct {
 	BundleName string
 
 	// Virtual machine configuration
-	Name            string
-	Memory          int
-	CPUs            int
-	DiskSize        int
-	ImageSourcePath string
-	ImageFormat     string
-	SSHKeyPath      string
-	KubeConfig      string
-	SharedDirs      []string
+	Name              string
+	Memory            int
+	CPUs              int
+	DiskSize          int
+	ImageSourcePath   string
+	ImageFormat       string
+	SSHKeyPath        string
+	KubeConfig        string
+	SharedDirs        []string
+	SharedDirPassword string
+	SharedDirUsername string
 
 	// macOS specific configuration
 	KernelCmdLine string

pkg/crc/machine/driver.go

@@ -57,3 +57,19 @@ func setDiskSize(host *host.Host, diskSizeGiB int) error {
 
 	return updateDriverValue(host, diskSizeSetter)
 }
+
+func setSharedDirPassword(host *host.Host, password string) error {
+	driver, err := loadDriverConfig(host)
+	if err != nil {
+		return err
+	}
+
+	if len(driver.SharedDirs) == 0 {
+		return nil
+	}
+
+	for i := range driver.SharedDirs {
+		driver.SharedDirs[i].Password = password
+	}
+	return updateDriverStruct(host, driver)
+}

pkg/crc/machine/driver_darwin.go

@@ -11,6 +11,7 @@ import (
 	machineVf "github.com/code-ready/crc/pkg/drivers/vfkit"
 	"github.com/code-ready/crc/pkg/libmachine"
 	"github.com/code-ready/crc/pkg/libmachine/host"
+	"github.com/code-ready/machine/libmachine/drivers"
 )
 
 func newHost(api libmachine.API, machineConfig config.MachineConfig) (*host.Host, error) {
@@ -64,3 +65,7 @@ func updateKernelArgs(vm *virtualMachine) error {
 	}
 	return vm.api.Save(vm.Host)
 }
+
+func updateDriverStruct(host *host.Host, driver *machineVf.Driver) error {
+	return drivers.ErrNotImplemented
+}

pkg/crc/machine/driver_linux.go

@@ -10,6 +10,7 @@ import (
 	"github.com/code-ready/crc/pkg/libmachine"
 	"github.com/code-ready/crc/pkg/libmachine/host"
 	machineLibvirt "github.com/code-ready/machine/drivers/libvirt"
+	"github.com/code-ready/machine/libmachine/drivers"
 )
 
 func newHost(api libmachine.API, machineConfig config.MachineConfig) (*host.Host, error) {
@@ -47,3 +48,7 @@ func (r *RPCServerDriver) SetConfigRaw(data []byte, _ *struct{}) error {
 	return json.Unmarshal(data, &r.ActualDriver)
 }
 */
+
+func updateDriverStruct(host *host.Host, driver *machineLibvirt.Driver) error {
+	return drivers.ErrNotImplemented
+}

pkg/crc/machine/driver_windows.go

@@ -37,3 +37,8 @@ func updateDriverConfig(host *host.Host, driver *machineHyperv.Driver) error {
 func updateKernelArgs(vm *virtualMachine) error {
 	return nil
 }
+
+func updateDriverStruct(host *host.Host, driver *machineHyperv.Driver) error {
+	host.Driver = driver
+	return nil
+}

pkg/crc/machine/hyperv/driver_windows.go

@@ -1,11 +1,15 @@
 package hyperv
 
 import (
+	"path/filepath"
+	"strings"
+
 	"github.com/code-ready/crc/pkg/crc/constants"
 	"github.com/code-ready/crc/pkg/crc/machine/config"
 	"github.com/code-ready/crc/pkg/crc/network"
 	"github.com/code-ready/crc/pkg/drivers/hyperv"
 	winnet "github.com/code-ready/crc/pkg/os/windows/network"
+	"github.com/code-ready/machine/libmachine/drivers"
 )
 
 func CreateHost(machineConfig config.MachineConfig) *hyperv.Driver {
@@ -23,5 +27,35 @@ func CreateHost(machineConfig config.MachineConfig) *hyperv.Driver {
 		hypervDriver.VirtualSwitch = switchName
 	}
 
+	hypervDriver.SharedDirs = configureShareDirs(machineConfig)
 	return hypervDriver
 }
+
+// converts a path like c:\users\crc to /mnt/c/users/crc
+func convertToUnixPath(path string) string {
+	/* podman internally converts windows style paths like C:\Users\crc  to
+	 * /mnt/c/Users/crc so it expects the shared folder to be mounted under
+	 * '/mnt' instead of '/' like in the case of macOS and linux
+	 * see: https://github.com/containers/podman/blob/468aa6478c73e4acd8708ce8bb0bb5a056f329c2/pkg/specgen/winpath.go#L24-L59
+	 */
+	path = filepath.ToSlash(path)
+	if len(path) > 1 && path[1] == ':' {
+		return ("/mnt/" + strings.ToLower(path[0:1]) + path[2:])
+	}
+	return path
+}
+
+func configureShareDirs(machineConfig config.MachineConfig) []drivers.SharedDir {
+	var sharedDirs []drivers.SharedDir
+	for _, dir := range machineConfig.SharedDirs {
+		sharedDir := drivers.SharedDir{
+			Source:   dir,
+			Target:   convertToUnixPath(dir),
+			Tag:      "crc-dir0", // smb share 'crc-dir0' is created in the msi
+			Type:     "cifs",
+			Username: machineConfig.SharedDirUsername,
+		}
+		sharedDirs = append(sharedDirs, sharedDir)
+	}
+	return sharedDirs
+}

pkg/crc/machine/hyperv/driver_windows_test.go

@@ -0,0 +1,12 @@
+package hyperv
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestConvertToUnixPath(t *testing.T) {
+	assert.Equal(t, "/mnt/c/Users/crc", convertToUnixPath("C:\\Users\\crc"))
+	assert.Equal(t, "/mnt/d/Users/crc", convertToUnixPath("d:\\Users\\crc"))
+}

pkg/crc/machine/start.go

@@ -99,6 +99,14 @@ func (client *client) updateVMConfig(startConfig types.StartConfig, vm *virtualM
 		}
 	}
 
+	// we want to set the shared dir password on-the-fly to be used
+	// we do not want this value to be persisted to disk
+	if startConfig.SharedDirPassword != "" {
+		if err := setSharedDirPassword(vm.Host, startConfig.SharedDirPassword); err != nil {
+			return fmt.Errorf("Failed to set shared dir password: %w", err)
+		}
+	}
+
 	return nil
 }
 
@@ -178,6 +186,11 @@ func configureSharedDirs(vm *virtualMachine, sshRunner *crcssh.Runner) error {
 			if _, _, err := sshRunner.RunPrivileged(fmt.Sprintf("Mounting %s", mount.Target), "mount", "-o", "context=\"system_u:object_r:container_file_t:s0\"", "-t", mount.Type, mount.Tag, mount.Target); err != nil {
 				return err
 			}
+		case "cifs":
+			smbUncPath := fmt.Sprintf("//%s/%s", hostVirtualIP, mount.Tag)
+			if _, _, err := sshRunner.RunPrivate("sudo", "mount", "-o", fmt.Sprintf("rw,uid=core,gid=core,username='%s',password='%s'", mount.Username, mount.Password), "-t", mount.Type, smbUncPath, mount.Target); err != nil {
+				return fmt.Errorf("Failed to mount CIFS/SMB share '%s' please make sure configured password is correct: %w", mount.Tag, err)
+			}
 		default:
 			return fmt.Errorf("Unknown Shared dir type requested: %s", mount.Type)
 		}
@@ -233,19 +246,21 @@ func (client *client) Start(ctx context.Context, startConfig types.StartConfig)
 		}
 
 		machineConfig := config.MachineConfig{
-			Name:            client.name,
-			BundleName:      bundleName,
-			CPUs:            startConfig.CPUs,
-			Memory:          startConfig.Memory,
-			DiskSize:        startConfig.DiskSize,
-			NetworkMode:     client.networkMode(),
-			ImageSourcePath: crcBundleMetadata.GetDiskImagePath(),
-			ImageFormat:     crcBundleMetadata.GetDiskImageFormat(),
-			SSHKeyPath:      crcBundleMetadata.GetSSHKeyPath(),
-			KernelCmdLine:   crcBundleMetadata.GetKernelCommandLine(),
-			Initramfs:       crcBundleMetadata.GetInitramfsPath(),
-			Kernel:          crcBundleMetadata.GetKernelPath(),
-			SharedDirs:      sharedDirs,
+			Name:              client.name,
+			BundleName:        bundleName,
+			CPUs:              startConfig.CPUs,
+			Memory:            startConfig.Memory,
+			DiskSize:          startConfig.DiskSize,
+			NetworkMode:       client.networkMode(),
+			ImageSourcePath:   crcBundleMetadata.GetDiskImagePath(),
+			ImageFormat:       crcBundleMetadata.GetDiskImageFormat(),
+			SSHKeyPath:        crcBundleMetadata.GetSSHKeyPath(),
+			KernelCmdLine:     crcBundleMetadata.GetKernelCommandLine(),
+			Initramfs:         crcBundleMetadata.GetInitramfsPath(),
+			Kernel:            crcBundleMetadata.GetKernelPath(),
+			SharedDirs:        sharedDirs,
+			SharedDirPassword: startConfig.SharedDirPassword,
+			SharedDirUsername: startConfig.SharedDirUsername,
 		}
 		if crcBundleMetadata.IsOpenShift() {
 			machineConfig.KubeConfig = crcBundleMetadata.GetKubeConfigPath()

pkg/crc/machine/types/types.go

@@ -30,7 +30,9 @@ type StartConfig struct {
 	Preset crcpreset.Preset
 
 	// Shared dirs
-	EnableSharedDirs bool
+	EnableSharedDirs  bool
+	SharedDirPassword string
+	SharedDirUsername string
 
 	// Ports to access openshift routes
 	IngressHTTPPort  uint

pkg/crc/machine/vsock.go

@@ -76,6 +76,7 @@ func listOpenPorts(daemonClient *daemonclient.Client) ([]types.ExposeRequest, er
 
 const (
 	virtualMachineIP = "192.168.127.2"
+	hostVirtualIP    = "192.168.127.254"
 	internalSSHPort  = "22"
 	localIP          = "127.0.0.1"
 	remoteHTTPPort   = "80"