PEFS is a kernel level stacked cryptographic filesystem for FreeBSD.

Key features:
* Transparently runs on top of existing file systems
* Random per file tweak value for encryption
* Stores metadata only in encrypted file name
* Arbitrary number of keys per file system, mixing keys in same
  directory and key chains
* Modern cryptographic algorithms: AES and Camellia in XTS mode,
  PKCS#5v2 and HKDF for key generation.

WWW: http://github.com/glk/pefs
WWW: http://wiki.freebsd.org/PEFS