Ccrypt uses the Rijndael cipher with 256-bit encryption and encrypted files are portable across Linux, Windows, and Macintosh OS-X
Usage and options:
- command-line interface
- Menu > Personal > ccrypt
- ROX right-click context menu with the option to encrypt
The passphrase needs to be typed twice; if the passphrases are not identical, nothing is encrypted.
Encrypted files are saved with the file extension .cpt.
Passphrases should be at least 8 characters long if you value your privacy. All characters supplied are significant since the stronger your passphrase the more secure your data will be.
WARNING: If you forget or lose the encryption key (passphrase) your file may never be opened again
For secure file deletion, use ccrypt to encrypt the file before deleting it.
Any files with the .cpt extension will be assumed to have been encrypted with ccrypt, and so ccrypt will attempt to decrypt them. Any other input files will be encrypted.
Answer: Yes, it is. Ccrypt uses strong 256-bit encryption which is currently considered to be unbreakable. Technically speaking, ccrypt uses the Rijndael block cipher. Rijndael was also chosen for the "Advanced Encryption Standard" (AES) by the U.S. government (see http://www.nist.gov/aes/). However, there is one difference between ccrypt and AES: ccrypt uses the 256-bit block size allowed by the Rijndael cipher, whereas the AES standard currently only covers the 128-bit block size. This does not mean that ccrypt is less secure than AES, only that it is not technically covered by the AES standard. Thus, it would be wrong to say that ccrypt is an "AES" encryption tool. Nevertheless, the cipher used by ccrypt is under much public scrutiny and, supposing that it were ever broken, this would be widely publicized immediately. As of this writing, this cipher has not been broken, and the experts think that it will be good for at least several decades.
Many encryption algorithms exist. The more popular options were submitted to the National Institute of Standards and Technology or NIST for the Advanced Encryption Standard (AES) competition. The winner, Rijndael, got 86 votes while Serpent got 59 votes, Twofish 31 votes, RC6 23 votes and MARS 13 votes. NIST chose Rijndael as its standard.