Documentation
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Overview ¶
Package fileutil provides utility functions for working with file paths and file operations.
Index ¶
- func CopyFile(src, dst string) error
- func DirExists(path string) bool
- func ExtractFileFromTar(data []byte, path string) ([]byte, error)
- func FileExists(path string) bool
- func IsDirEmpty(path string) bool
- func MustBeWithin(base, candidate string) error
- func ValidateAbsolutePath(path string) (string, error)
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func ExtractFileFromTar ¶ added in v0.49.0
ExtractFileFromTar extracts a single file from a tar archive. Uses Go's standard archive/tar for cross-platform compatibility instead of spawning an external tar process which may not be available on all platforms.
path must be a local, relative path (no absolute paths or ".." components). filepath.IsLocal is used to enforce this for both the search target and each tar entry name, guarding against path-traversal payloads embedded in archives.
func FileExists ¶ added in v0.47.0
FileExists checks if a file exists and is not a directory.
func IsDirEmpty ¶ added in v0.47.0
IsDirEmpty checks if a directory is empty.
func MustBeWithin ¶ added in v0.64.1
MustBeWithin checks that candidate is located within the base directory tree. Both paths are resolved via filepath.EvalSymlinks (with filepath.Abs as fallback when a path does not yet exist) before comparison, so neither ".." components nor symlinks pointing outside base can be used to escape.
Returns an error when:
- Either path cannot be resolved to an absolute form.
- The resolved candidate path starts outside the resolved base directory.
func ValidateAbsolutePath ¶
ValidateAbsolutePath validates that a file path is absolute and safe to use. It performs the following security checks:
- Cleans the path using filepath.Clean to normalize . and .. components
- Verifies the path is absolute to prevent relative path traversal attacks
Returns the cleaned absolute path if validation succeeds, or an error if:
- The path is empty
- The path is relative (not absolute)
This function should be used before any file operations (read, write, stat, etc.) to ensure defense-in-depth security against path traversal vulnerabilities.
Example:
cleanPath, err := fileutil.ValidateAbsolutePath(userInputPath)
if err != nil {
return fmt.Errorf("invalid path: %w", err)
}
content, err := os.ReadFile(cleanPath)
Types ¶
This section is empty.
Source Files