Icecrypt
icecrypt is composed of the ice and deice programs to encrypt and decrypt files using the ICE encryption algorithm. The data is encrypted in Cipher Block Chaining (CBC) mode, with an initialization vector by default obtained from the gettimeofday(2) function.
The ICE encryption algorithm allows key lengths of any multiple of 64 bits by specifying the encryption level. Specifying a level greater than 1 allows long passwords, and correspondingly higher security. The drawback is slower encryption.
This program only uses the lower 7 bits from each character in the password, so the first 10 characters are significant when using levels 0 or 1. For higher levels n, the key size is 64n, so the useful password length will be (64n + 6)/7. Short passwords will be padded out with zeroes.
