3 Round DES

This is an implementation of DES weakened till the point of crackability. Specifically:

We are using only 3 rounds, using subkeys 1, 2 and 3 only;
We are not using the Initial or Final Permutations;

Using Differentail Cryptanalysis easily cracks this version of DES, as is explained in: Cryptography: Theory and Practice, Douglas R. Stinson, CRC Press. Compared to the discussion in this text, we do swap left and right 32 bits, in order to maintain decryption/encryption symmetry.

Enter an exactly 16-hexadecimal digit to encode with the secret key and an exactly 16-hexadecimal digit for the secret key:

INPUT
KEY

Notes:

This page is intended for students of MTH 609.
Code used is highly modified from the original RSAREF.
This is a very weak cryptosystem for a chosen plaintext attack.
See the C code and Header file for more details.

Burton Rosenberg
Updated: Sat Sep 4 14:03:43 EDT 2004