Validates directory tree against specification

 The mtree utility compares a file hierarchy against a specification,
 creates a specification for a file hierarchy, or modifies a specification.
 This specification can be controlled by the user, but typically includes
 file/directory/symlink names, ownership information, permission bits, and
 so forth. It may optionally also include various hashes, such as SHA-256
 or MD5.
 .
 This mtree utility can understand its own files, as well as those generated
 by the FreeBSD mtree (in Debian as fmtree in freebsd-buildutils and
 freebsd-glue) and bsdtar/libarchive.