Ccrypt

ccrypt is a utility for the secure encryption and decryption of 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 cypher, the same cipher used in the AES standard. However, in the AES standard a 128-bit block size is used, whereas ccrypt uses a 256-bit block size. ccrypt commonly uses the .cpt file extension for encrypted files.

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