added fs encryption overlay

pkg/fs/fs.go

@@ -6,6 +6,7 @@ import (
 	"cachefs/pkg/provider"
 	"cachefs/pkg/provider/parse"
 	"context"
+	"encoding/hex"
 	"errors"
 	"fmt"
 	stdfs "io/fs"
@@ -31,15 +32,28 @@ type FS struct {
 	ph *PreloadHandler
 }
 
-func NewFS(quota int64, max int, src, dst, metadata string, log logr.Logger) (fs *FS, err error) {
+func NewFS(quota int64, max int, src, srckey, dst, dstkey, metadata string, log logr.Logger) (fs *FS, err error) {
 	if src == dst {
 		return nil, errors.New("src and dst path can not be equal")
 	}
-	srcfs, err := parse.FS(src)
+	var srck, dstk []byte
+	if srckey != "" {
+		srck, err = hex.DecodeString(srckey)
+		if err != nil {
+			return nil, fmt.Errorf("srckey: %w", err)
+		}
+	}
+	if dstkey != "" {
+		dstk, err = hex.DecodeString(dstkey)
+		if err != nil {
+			return nil, fmt.Errorf("dstkey: %w", err)
+		}
+	}
+	srcfs, err := parse.FS(src, srck)
 	if err != nil {
 		return nil, fmt.Errorf("srcfs: %w", err)
 	}
-	dstfs, err := parse.FS(dst)
+	dstfs, err := parse.FS(dst, dstk)
 	if err != nil {
 		return nil, fmt.Errorf("dstfs: %w", err)
 	}