Close out the repository audit

internal/promptdebug/secure_directory_other.go

@@ -3,141 +3,29 @@
 package promptdebug
 
 import (
-	"crypto/rand"
-	"encoding/hex"
-	"encoding/json"
 	"fmt"
-	"io"
-	"os"
 	"path/filepath"
-	"strings"
 )
 
-type secureDirectory struct {
-	root *os.Root
-}
+// secureDirectory has no enabled implementation on platforms that cannot
+// provide handle-relative, no-follow directory traversal.
+type secureDirectory struct{}
 
 func openSecureDirectory(path string) (*secureDirectory, error) {
 	if !filepath.IsAbs(path) {
 		return nil, fmt.Errorf("directory must be absolute")
 	}
-	if err := os.MkdirAll(path, debugDirectoryMode); err != nil {
-		return nil, err
-	}
-	info, err := os.Lstat(path)
-	if err != nil {
-		return nil, err
-	}
-	if info.Mode()&os.ModeSymlink != 0 || !info.IsDir() {
-		return nil, fmt.Errorf("prompt debug root is not a directory")
-	}
-	if err := os.Chmod(path, debugDirectoryMode); err != nil {
-		return nil, err
-	}
-	root, err := os.OpenRoot(path)
-	if err != nil {
-		return nil, err
-	}
-	return &secureDirectory{root: root}, nil
+	return nil, ErrSecureCaptureUnsupported
 }
 
-func (directory *secureDirectory) Close() error {
-	if directory == nil || directory.root == nil {
-		return nil
-	}
-	root := directory.root
-	directory.root = nil
-	return root.Close()
-}
-
-func (directory *secureDirectory) openDirectory(components ...string) (*secureDirectory, error) {
-	if directory == nil || directory.root == nil {
-		return nil, fmt.Errorf("prompt debug directory is closed")
-	}
-	for _, component := range components {
-		if err := validateSecureDirectoryName(component); err != nil {
-			return nil, err
-		}
-	}
-	path := filepath.Join(components...)
-	if err := directory.root.MkdirAll(path, debugDirectoryMode); err != nil {
-		return nil, err
-	}
-	child, err := directory.root.OpenRoot(path)
-	if err != nil {
-		return nil, err
-	}
-	return &secureDirectory{root: child}, nil
-}
-
-func validateSecureDirectoryName(name string) error {
-	if name == "" || name == "." || name == ".." || strings.ContainsRune(name, filepath.Separator) {
-		return fmt.Errorf("prompt debug directory component %q is invalid", name)
-	}
+func (*secureDirectory) Close() error {
 	return nil
 }
 
-func (directory *secureDirectory) writeJSON(name string, value any) error {
-	if directory == nil || directory.root == nil {
-		return fmt.Errorf("prompt debug directory is closed")
-	}
-	if err := validateSecureDirectoryName(name); err != nil {
-		return err
-	}
-	data, err := json.MarshalIndent(value, "", "  ")
-	if err != nil {
-		return fmt.Errorf("marshal prompt debug artifact: %w", err)
-	}
-	if info, err := directory.root.Lstat(name); err == nil {
-		if info.Mode()&os.ModeSymlink != 0 || !info.Mode().IsRegular() {
-			return fmt.Errorf("prompt debug file %q is not a regular file", name)
-		}
-	} else if !os.IsNotExist(err) {
-		return err
-	}
-	temporaryName, temporary, err := directory.createTemporaryFile(name)
-	if err != nil {
-		return err
-	}
-	defer func() {
-		if temporary != nil {
-			_ = temporary.Close()
-		}
-		_ = directory.root.Remove(temporaryName)
-	}()
-	if err := temporary.Chmod(debugFileMode); err != nil {
-		return err
-	}
-	if written, err := temporary.Write(data); err != nil {
-		return err
-	} else if written != len(data) {
-		return io.ErrShortWrite
-	}
-	if err := temporary.Close(); err != nil {
-		return err
-	}
-	temporary = nil
-	if err := directory.root.Rename(temporaryName, name); err != nil {
-		return fmt.Errorf("replace prompt debug file %q: %w", name, err)
-	}
-	return nil
+func (*secureDirectory) openDirectory(...string) (*secureDirectory, error) {
+	return nil, ErrSecureCaptureUnsupported
 }
 
-func (directory *secureDirectory) createTemporaryFile(name string) (string, *os.File, error) {
-	for attempt := 0; attempt < 16; attempt++ {
-		random := make([]byte, 12)
-		if _, err := rand.Read(random); err != nil {
-			return "", nil, err
-		}
-		temporaryName := "." + name + "." + hex.EncodeToString(random) + ".tmp"
-		temporary, err := directory.root.OpenFile(temporaryName, os.O_WRONLY|os.O_CREATE|os.O_EXCL, debugFileMode)
-		if os.IsExist(err) {
-			continue
-		}
-		if err != nil {
-			return "", nil, err
-		}
-		return temporaryName, temporary, nil
-	}
-	return "", nil, fmt.Errorf("create temporary prompt debug file: too many name collisions")
+func (*secureDirectory) writeJSON(string, any) error {
+	return ErrSecureCaptureUnsupported
 }