go.mod github.com/Microsoft/hcsshim v0.8.16

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor/github.com/Microsoft/hcsshim/computestorage/helpers.go

@@ -0,0 +1,193 @@
+package computestorage
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"syscall"
+
+	"github.com/Microsoft/go-winio/pkg/security"
+	"github.com/Microsoft/go-winio/vhd"
+	"github.com/pkg/errors"
+	"golang.org/x/sys/windows"
+)
+
+const defaultVHDXBlockSizeInMB = 1
+
+// SetupContainerBaseLayer is a helper to setup a containers scratch. It
+// will create and format the vhdx's inside and the size is configurable with the sizeInGB
+// parameter.
+//
+// `layerPath` is the path to the base container layer on disk.
+//
+// `baseVhdPath` is the path to where the base vhdx for the base layer should be created.
+//
+// `diffVhdPath` is the path where the differencing disk for the base layer should be created.
+//
+// `sizeInGB` is the size in gigabytes to make the base vhdx.
+func SetupContainerBaseLayer(ctx context.Context, layerPath, baseVhdPath, diffVhdPath string, sizeInGB uint64) (err error) {
+	var (
+		hivesPath  = filepath.Join(layerPath, "Hives")
+		layoutPath = filepath.Join(layerPath, "Layout")
+	)
+
+	// We need to remove the hives directory and layout file as `SetupBaseOSLayer` fails if these files
+	// already exist. `SetupBaseOSLayer` will create these files internally. We also remove the base and
+	// differencing disks if they exist in case we're asking for a different size.
+	if _, err := os.Stat(hivesPath); err == nil {
+		if err := os.RemoveAll(hivesPath); err != nil {
+			return errors.Wrap(err, "failed to remove prexisting hives directory")
+		}
+	}
+	if _, err := os.Stat(layoutPath); err == nil {
+		if err := os.RemoveAll(layoutPath); err != nil {
+			return errors.Wrap(err, "failed to remove prexisting layout file")
+		}
+	}
+
+	if _, err := os.Stat(baseVhdPath); err == nil {
+		if err := os.RemoveAll(baseVhdPath); err != nil {
+			return errors.Wrap(err, "failed to remove base vhdx path")
+		}
+	}
+	if _, err := os.Stat(diffVhdPath); err == nil {
+		if err := os.RemoveAll(diffVhdPath); err != nil {
+			return errors.Wrap(err, "failed to remove differencing vhdx")
+		}
+	}
+
+	createParams := &vhd.CreateVirtualDiskParameters{
+		Version: 2,
+		Version2: vhd.CreateVersion2{
+			MaximumSize:      sizeInGB * 1024 * 1024 * 1024,
+			BlockSizeInBytes: defaultVHDXBlockSizeInMB * 1024 * 1024,
+		},
+	}
+	handle, err := vhd.CreateVirtualDisk(baseVhdPath, vhd.VirtualDiskAccessNone, vhd.CreateVirtualDiskFlagNone, createParams)
+	if err != nil {
+		return errors.Wrap(err, "failed to create vhdx")
+	}
+
+	defer func() {
+		if err != nil {
+			_ = syscall.CloseHandle(handle)
+			os.RemoveAll(baseVhdPath)
+			os.RemoveAll(diffVhdPath)
+		}
+	}()
+
+	if err = FormatWritableLayerVhd(ctx, windows.Handle(handle)); err != nil {
+		return err
+	}
+	// Base vhd handle must be closed before calling SetupBaseLayer in case of Container layer
+	if err = syscall.CloseHandle(handle); err != nil {
+		return errors.Wrap(err, "failed to close vhdx handle")
+	}
+
+	options := OsLayerOptions{
+		Type: OsLayerTypeContainer,
+	}
+
+	// SetupBaseOSLayer expects an empty vhd handle for a container layer and will
+	// error out otherwise.
+	if err = SetupBaseOSLayer(ctx, layerPath, 0, options); err != nil {
+		return err
+	}
+	// Create the differencing disk that will be what's copied for the final rw layer
+	// for a container.
+	if err = vhd.CreateDiffVhd(diffVhdPath, baseVhdPath, defaultVHDXBlockSizeInMB); err != nil {
+		return errors.Wrap(err, "failed to create differencing disk")
+	}
+
+	if err = security.GrantVmGroupAccess(baseVhdPath); err != nil {
+		return errors.Wrapf(err, "failed to grant vm group access to %s", baseVhdPath)
+	}
+	if err = security.GrantVmGroupAccess(diffVhdPath); err != nil {
+		return errors.Wrapf(err, "failed to grant vm group access to %s", diffVhdPath)
+	}
+	return nil
+}
+
+// SetupUtilityVMBaseLayer is a helper to setup a UVMs scratch space. It will create and format
+// the vhdx inside and the size is configurable by the sizeInGB parameter.
+//
+// `uvmPath` is the path to the UtilityVM filesystem.
+//
+// `baseVhdPath` is the path to where the base vhdx for the UVM should be created.
+//
+// `diffVhdPath` is the path where the differencing disk for the UVM should be created.
+//
+// `sizeInGB` specifies the size in gigabytes to make the base vhdx.
+func SetupUtilityVMBaseLayer(ctx context.Context, uvmPath, baseVhdPath, diffVhdPath string, sizeInGB uint64) (err error) {
+	// Remove the base and differencing disks if they exist in case we're asking for a different size.
+	if _, err := os.Stat(baseVhdPath); err == nil {
+		if err := os.RemoveAll(baseVhdPath); err != nil {
+			return errors.Wrap(err, "failed to remove base vhdx")
+		}
+	}
+	if _, err := os.Stat(diffVhdPath); err == nil {
+		if err := os.RemoveAll(diffVhdPath); err != nil {
+			return errors.Wrap(err, "failed to remove differencing vhdx")
+		}
+	}
+
+	// Just create the vhdx for utilityVM layer, no need to format it.
+	createParams := &vhd.CreateVirtualDiskParameters{
+		Version: 2,
+		Version2: vhd.CreateVersion2{
+			MaximumSize:      sizeInGB * 1024 * 1024 * 1024,
+			BlockSizeInBytes: defaultVHDXBlockSizeInMB * 1024 * 1024,
+		},
+	}
+	handle, err := vhd.CreateVirtualDisk(baseVhdPath, vhd.VirtualDiskAccessNone, vhd.CreateVirtualDiskFlagNone, createParams)
+	if err != nil {
+		return errors.Wrap(err, "failed to create vhdx")
+	}
+
+	defer func() {
+		if err != nil {
+			_ = syscall.CloseHandle(handle)
+			os.RemoveAll(baseVhdPath)
+			os.RemoveAll(diffVhdPath)
+		}
+	}()
+
+	// If it is a UtilityVM layer then the base vhdx must be attached when calling
+	// `SetupBaseOSLayer`
+	attachParams := &vhd.AttachVirtualDiskParameters{
+		Version: 2,
+	}
+	if err := vhd.AttachVirtualDisk(handle, vhd.AttachVirtualDiskFlagNone, attachParams); err != nil {
+		return errors.Wrapf(err, "failed to attach virtual disk")
+	}
+
+	options := OsLayerOptions{
+		Type: OsLayerTypeVM,
+	}
+	if err := SetupBaseOSLayer(ctx, uvmPath, windows.Handle(handle), options); err != nil {
+		return err
+	}
+
+	// Detach and close the handle after setting up the layer as we don't need the handle
+	// for anything else and we no longer need to be attached either.
+	if err = vhd.DetachVirtualDisk(handle); err != nil {
+		return errors.Wrap(err, "failed to detach vhdx")
+	}
+	if err = syscall.CloseHandle(handle); err != nil {
+		return errors.Wrap(err, "failed to close vhdx handle")
+	}
+
+	// Create the differencing disk that will be what's copied for the final rw layer
+	// for a container.
+	if err = vhd.CreateDiffVhd(diffVhdPath, baseVhdPath, defaultVHDXBlockSizeInMB); err != nil {
+		return errors.Wrap(err, "failed to create differencing disk")
+	}
+
+	if err := security.GrantVmGroupAccess(baseVhdPath); err != nil {
+		return errors.Wrapf(err, "failed to grant vm group access to %s", baseVhdPath)
+	}
+	if err := security.GrantVmGroupAccess(diffVhdPath); err != nil {
+		return errors.Wrapf(err, "failed to grant vm group access to %s", diffVhdPath)
+	}
+	return nil
+}