lib9p

commit b63eedc3cfb37df5e27b875d54ad387f7ec52970
parent 53741b97afe48ed34f444754b0bdf55c78ca8bef
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Wed, 17 Jan 2024 13:16:20 +0900

check uid in Create

Diffstat:
M
diskfs/fs.go
 | 
32
+++++++++++++++++++-------------
A
testdir/glenda/a
 | 
1
+

2 files changed, 20 insertions(+), 13 deletions(-)
diff --git a/diskfs/fs.go b/diskfs/fs.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io/fs"
 	"os"
+	"os/user"
 	"path/filepath"
 	"strings"
 
@@ -64,9 +65,23 @@ func (fsys *FS) OpenFile(name string, flag int) (lib9p.File, error) {
 	return &File{fs: fsys, path: name, file: osf}, nil
 }
 
-// TODO: check uid
-// BUG: check uid. it can be a security hole.
 func (fsys *FS) Create(name string, uid string, omode lib9p.OpenMode, perm lib9p.FileMode) (lib9p.File, error) {
+	usr, err := user.Current()
+	if err != nil {
+		return nil, &fs.PathError{
+			Op:   "create",
+			Path: name,
+			Err:  err,
+		}
+	}
+	if usr.Username != uid {
+		return nil, &fs.PathError{
+			Op:   "create",
+			Path: name,
+			Err:  fmt.Errorf("file creation by a user other than the server's " +
+				"uid is not implemented"),
+		}
+	}
 	if !fs.ValidPath(name) {
 		return nil, &fs.PathError{
 			Op:   "create",
@@ -88,17 +103,8 @@ func (fsys *FS) Create(name string, uid string, omode lib9p.OpenMode, perm lib9p
 	if omode&lib9p.OTRUNC != 0 {
 		flag |= os.O_TRUNC
 	}
-	if omode&lib9p.ORCLOSE != 0 {
-		return nil, &fs.PathError{
-			Op:   "create",
-			Path: name,
-			Err:  fmt.Errorf("orclose not implemented"),
-		}
-	}
-	var (
-		osfile *os.File
-		err    error
-	)
+	// ORCLOSE is handled by the library.
+	var osfile *os.File
 	if perm&os.ModeDir != 0 {
 		if err := os.Mkdir(ospath, perm); err != nil {
 			return nil, &fs.PathError{
diff --git a/testdir/glenda/a b/testdir/glenda/a
@@ -0,0 +1 @@
+a