symmetric encryption broken

Matthias Urlichs smurf@noris.de
Fri Mar 9 22:14:08 2001


Hi,

Michael H. Warfield:

> Huh... Wait a minute. You're encrypting it once and then
> encrypting it a second time. What are you trying to accomplish here?
>
Some ciphers are symmetric. If you DES-encrypt something, and then "encrypt" the ciphertext again, you magically get the plaintext back. The same thing works with any cipher algorithm which computes a secure hash and XORs it with the plaintext. (You could use MD5 as a cipher that way.) -- Matthias Urlichs | noris network AG | http://smurf.noris.de/