pkg/containerfs: make ResolveScopedPath a free fn

Signed-off-by: Cory Snider <csnider@mirantis.com>

builder/dockerfile/copy.go

@@ -45,7 +45,7 @@ type copyInfo struct {
 }
 
 func (c copyInfo) fullPath() (string, error) {
-	return c.root.ResolveScopedPath(c.path, true)
+	return containerfs.ResolveScopedPath(c.root.Path(), c.path)
 }
 
 func newCopyInfoFromSource(source builder.Source, path string, hash string) copyInfo {

builder/remotecontext/archive.go

@@ -117,7 +117,7 @@ func (c *archiveContext) Hash(path string) (string, error) {
 
 func normalize(path string, root containerfs.ContainerFS) (cleanPath, fullPath string, err error) {
 	cleanPath = root.Clean(string(root.Separator()) + path)[1:]
-	fullPath, err = root.ResolveScopedPath(path, true)
+	fullPath, err = containerfs.ResolveScopedPath(root.Path(), path)
 	if err != nil {
 		return "", "", errors.Wrapf(err, "forbidden path outside the build context: %s (%s)", path, cleanPath)
 	}

builder/remotecontext/detect.go

@@ -13,6 +13,7 @@ import (
 	"github.com/docker/docker/builder"
 	"github.com/docker/docker/builder/remotecontext/urlutil"
 	"github.com/docker/docker/errdefs"
+	"github.com/docker/docker/pkg/containerfs"
 	"github.com/docker/docker/pkg/fileutils"
 	"github.com/moby/buildkit/frontend/dockerfile/dockerignore"
 	"github.com/moby/buildkit/frontend/dockerfile/parser"
@@ -175,7 +176,7 @@ func StatAt(remote builder.Source, path string) (os.FileInfo, error) {
 
 // FullPath is a helper for getting a full path for a path from a source
 func FullPath(remote builder.Source, path string) (string, error) {
-	fullPath, err := remote.Root().ResolveScopedPath(path, true)
+	fullPath, err := containerfs.ResolveScopedPath(remote.Root().Path(), path)
 	if err != nil {
 		if runtime.GOOS == "windows" {
 			return "", fmt.Errorf("failed to resolve scoped path %s (%s): %s. Possible cause is a forbidden path outside the build context", path, fullPath, err)

container/container.go

@@ -304,7 +304,7 @@ func (container *Container) GetResourcePath(path string) (string, error) {
 	}
 	// IMPORTANT - These are paths on the OS where the daemon is running, hence
 	// any filepath operations must be done in an OS agnostic way.
-	r, e := container.BaseFS.ResolveScopedPath(path, false)
+	r, e := containerfs.ResolveScopedPath(container.BaseFS.Path(), containerfs.CleanScopedPath(path))
 
 	// Log this here on the daemon side as there's otherwise no indication apart
 	// from the error being propagated all the way back to the client. This makes

pkg/containerfs/containerfs.go

@@ -14,13 +14,6 @@ type ContainerFS interface {
 	// on the local system, so the continuity operations must be used
 	Path() string
 
-	// ResolveScopedPath evaluates the given path scoped to the root.
-	// For example, if root=/a, and path=/b/c, then this function would return /a/b/c.
-	// If rawPath is true, then the function will not preform any modifications
-	// before path resolution. Otherwise, the function will clean the given path
-	// by making it an absolute path.
-	ResolveScopedPath(path string, rawPath bool) (string, error)
-
 	Driver
 }
 
@@ -52,10 +45,8 @@ func (l *local) Path() string {
 	return l.path
 }
 
-func (l *local) ResolveScopedPath(path string, rawPath bool) (string, error) {
-	cleanedPath := path
-	if !rawPath {
-		cleanedPath = cleanScopedPath(path)
-	}
-	return symlink.FollowSymlinkInScope(filepath.Join(l.path, cleanedPath), l.path)
+// ResolveScopedPath evaluates the given path scoped to the root.
+// For example, if root=/a, and path=/b/c, then this function would return /a/b/c.
+func ResolveScopedPath(root, path string) (string, error) {
+	return symlink.FollowSymlinkInScope(filepath.Join(root, path), root)
 }

pkg/containerfs/containerfs_unix.go

@@ -5,7 +5,7 @@ package containerfs // import "github.com/docker/docker/pkg/containerfs"
 
 import "path/filepath"
 
-// cleanScopedPath preappends a to combine with a mnt path.
-func cleanScopedPath(path string) string {
+// CleanScopedPath preappends a to combine with a mnt path.
+func CleanScopedPath(path string) string {
 	return filepath.Join(string(filepath.Separator), path)
 }

pkg/containerfs/containerfs_windows.go

@@ -2,9 +2,9 @@ package containerfs // import "github.com/docker/docker/pkg/containerfs"
 
 import "path/filepath"
 
-// cleanScopedPath removes the C:\ syntax, and prepares to combine
+// CleanScopedPath removes the C:\ syntax, and prepares to combine
 // with a volume path
-func cleanScopedPath(path string) string {
+func CleanScopedPath(path string) string {
 	if len(path) >= 2 {
 		c := path[0]
 		if path[1] == ':' && ('a' <= c && c <= 'z' || 'A' <= c && c <= 'Z') {