# Module Crypt_des.Cryptsystem

    module Cryptsystem: Cryptsystem_64.T

    type key

This is the internal, often preprocessed representation of keys.

    val encrypt_ecb : key -> int * int * int * int -> int * int * int * int

This is the ECB mode of the encryption function. The four ints are numbers from 0 to 65535, and given from MSB to LSB.

    val encrypt_ecb_int32 : key ->
           int32 -> int32 -> int32 Stdlib.ref -> int32 Stdlib.ref -> unit

The same as encrypt_ecb, but with an int32 interface

    val decrypt_ecb : key -> int * int * int * int -> int * int * int * int

This is the ECB mode of the decryption function. The four ints are numbers from 0 to 65535, and given from MSB to LSB.

    val decrypt_ecb_int32 : key ->
           int32 -> int32 -> int32 Stdlib.ref -> int32 Stdlib.ref -> unit

The same as decrypt_ecb, but with an int32 interface

    val prepare : string -> key

Prepares the string representation of a key.

    val textkey : key -> string

Gets the string representation back

    val is_weak : key -> bool

Determines whether the key is known as being weak. Do not use such keys.