feat: udpates

README.md

@@ -37,6 +37,7 @@ File ext `*.__encfile`:
 
 ```json
 {
+    "name": "<file name>",
     "iv": "<16 bytes IV in base64>"
 }
 ```

encfs/file.go

@@ -1,28 +1,121 @@
 package encfs
 
 import (
+	"crypto/rand"
+	"encoding/json"
+	"errors"
+	"io"
 	"os"
 	"syscall"
 
 	"github.com/spf13/afero"
 )
 
-type EncFile struct {
-	isDir  bool
-	closed bool
-	file   *os.File
+const EncFileExt = ".__encfile"
+
+var (
+	ErrFileForbiddenFileExt = errors.New("File ext is forbidden")
+)
+
+type EncFileMeta struct {
+	Name string `json:"name"`
+	Iv   []byte `json:"iv"`
 }
 
-func NewEncFile(file *os.File) (*EncFile, error) {
+func newEncFileMeta(name string) (*EncFileMeta, error) {
+	iv := make([]byte, 16)
+	_, err := rand.Read(iv)
+	if err != nil {
+		return nil, err
+	}
+	encFileMeta := &EncFileMeta{
+		Name: name,
+		Iv:   iv,
+	}
+	encFileMetaName := name + EncFileExt
+	encFileMetaFile, err := os.Create(encFileMetaName)
+	if err != nil {
+		return nil, err
+	}
+	defer func() {
+		_ = encFileMetaFile.Close()
+	}()
+	encFileMetaBytes, err := marshalEncFileMeta(encFileMeta)
+	if err != nil {
+		return nil, err
+	}
+	_, err = encFileMetaFile.Write(encFileMetaBytes)
+	if err != nil {
+		return nil, err
+	}
+	return encFileMeta, nil
+}
+
+func openEncFileMeta(name string) (*EncFileMeta, error) {
+	encFileMetaName := name + "." + EncFileExt
+	encFileMetaFile, err := os.Open(encFileMetaName)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	defer func() {
+		_ = encFileMetaFile.Close()
+	}()
+	encFileMetaBytes, err := io.ReadAll(encFileMetaFile)
+	if err != nil {
+		return nil, err
+	}
+	encFileMeta, err := unmarchalEncFileMeta(encFileMetaBytes)
+	if err != nil {
+		return nil, err
+	}
+	return encFileMeta, nil
+}
+
+func marshalEncFileMeta(encFileMeata *EncFileMeta) ([]byte, error) {
+	return json.Marshal(encFileMeata)
+}
+
+func unmarchalEncFileMeta(data []byte) (*EncFileMeta, error) {
+	var encFileMeta EncFileMeta
+	err := json.Unmarshal(data, &encFileMeta)
+	if err != nil {
+		return nil, err
+	}
+	return &encFileMeta, nil
+}
+
+type EncFile struct {
+	isDir       bool
+	closed      bool
+	encFileMeta *EncFileMeta
+	file        *os.File
+}
+
+func NewEncFile(name string, file *os.File, isCreate bool) (*EncFile, error) {
 	fileInfo, err := file.Stat()
 	if err != nil {
 		return nil, err
 	}
 	isDir := fileInfo.IsDir()
+	var encFileMeta *EncFileMeta = nil
+	if !isDir {
+		if isCreate {
+			encFileMeta, err = newEncFileMeta(name)
+		} else {
+			encFileMeta, err = openEncFileMeta(name)
+		}
+		if err != nil {
+			return nil, err
+		}
+	}
 	return &EncFile{
-		isDir:  isDir,
-		closed: false,
-		file:   file,
+		isDir:       isDir,
+		closed:      false,
+		encFileMeta: encFileMeta,
+		file:        file,
 	}, nil
 }
 

encfs/fs.go

@@ -2,6 +2,7 @@ package encfs
 
 import (
 	"os"
+	"strings"
 	"time"
 
 	"github.com/spf13/afero"
@@ -18,13 +19,16 @@ func NewEncFs() afero.Fs {
 func (EncFs) Name() string { return "EncFs" }
 
 func (EncFs) Create(name string) (afero.File, error) {
+	if err := checkFileExt(name); err != nil {
+		return nil, err
+	}
 	f, e := os.Create(name)
 	if f == nil {
 		// while this looks strange, we need to return a bare nil (of type nil) not
 		// a nil value of type *os.File or nil won't be nil
 		return nil, e
 	}
-	return convertOsFileToEncFile(f, e)
+	return convertOsFileToEncFile(name, f, e, true)
 }
 
 func (EncFs) Mkdir(name string, perm os.FileMode) error {
@@ -36,13 +40,16 @@ func (EncFs) MkdirAll(path string, perm os.FileMode) error {
 }
 
 func (EncFs) Open(name string) (afero.File, error) {
+	if err := checkFileExt(name); err != nil {
+		return nil, err
+	}
 	f, e := os.Open(name)
 	if f == nil {
 		// while this looks strange, we need to return a bare nil (of type nil) not
 		// a nil value of type *os.File or nil won't be nil
 		return nil, e
 	}
-	return convertOsFileToEncFile(f, e)
+	return convertOsFileToEncFile(name, f, e, false)
 }
 
 func (EncFs) OpenFile(name string, flag int, perm os.FileMode) (afero.File, error) {
@@ -99,12 +106,19 @@ func (EncFs) ReadlinkIfPossible(name string) (string, error) {
 	return os.Readlink(name)
 }
 
-func convertOsFileToEncFile(file *os.File, e error) (afero.File, error) {
+func checkFileExt(name string) error {
+	if strings.HasSuffix(name, EncFileExt) {
+		return ErrFileForbiddenFileExt
+	}
+	return nil
+}
+
+func convertOsFileToEncFile(name string, file *os.File, e error, isCreate bool) (afero.File, error) {
 	if e != nil {
 		return nil, e
 	}
 	// TODO add password, and IV etc ...
-	encFile, err := NewEncFile(file)
+	encFile, err := NewEncFile(name, file, isCreate)
 	if err != nil {
 		return nil, err
 	}

main.go

@@ -6,6 +6,7 @@ import (
 	"encoding/hex"
 	"fmt"
 	"math"
+	"os"
 
 	"git.hatter.ink/hatter/go-afero-encfs/encfs"
 	"github.com/spf13/afero"
@@ -94,6 +95,15 @@ func main() {
 		return
 	}
 	fmt.Println("write len: ", len)
+
+	f, err := os.Open("test2")
+	fmt.Println(f, "-", err, ", ", os.IsNotExist(err))
+
+	a, err := encFs.Open(".")
+	fs, err := a.Readdir(1000)
+	for _, ff := range fs {
+		fmt.Println(ff.Name())
+	}
 }
 
 func generateCtrEncryptBytes(key, iv []byte, offset, len int64) ([]byte, error) {