Ccrypt is a utility for encrypting and decrypting files and streams.
It was designed as a replacement for the standard unix crypt utility,
which is notorious for using a very weak encryption algorithm. ccrypt
is based on the Rijndael cipher, which is the U.S. government's chosen
candidate for the Advanced Encryption Standard (AES), see:
http://www.nist.gov/aes
This cipher is believed to provide very strong security.
Unlike unix crypt, the algorithm provided by ccrypt is not
symmetric, i.e., one must specify whether to encrypt or decrypt. The
most common way to invoke ccrypt is via the commands ccencrypt and
ccdecrypt. There is also a ccat command for decrypting a file directly
to the terminal, thus reducing the likelihood of leaving temporary
plaintext files around. In addition, there is a compatibility mode for
decrypting legacy unix crypt files. An emacs mode is also supplied
forediting encrypted text files.
Encryption and decryption depends on a keyword (or key phrase)
supplied by the user. By default, the user is prompted to enter a
keyword from the terminal. Keywords can consist of any number of
characters, and all characters are significant (although ccrypt
internally hashes the key to 256 bits). Longer keywords provide better
security than short ones, since they are less likely to be discovered
by exhaustive search.
For a detailed description of the encryption algorithm used by ccrypt, see the man page.
-> URL: http://hobbes.nmsu.edu/h-search.php?key=Ccrypt.1.9-os2
Source: OS2.org