Re: Got Plaintext and Ciphertext ... Want Algorithm


"Tuna Fish" <tunafish@xxxxxxxx> wrote in message
news:1vVeg.662$s77.639@xxxxxxxxxxx
It sounds like you need a Hex converter (or sthg similar).
Available online
for free.
http://www.mikezilla.com/exp0012.html



How will a hex converter help? It clearly isn't as simple as
that. The one thing that may help is that the length of the
cipher text (in bytes) is equal to the length of the plaintext
(in characters). Since adding a character at the end of the plain
text changes even the first byte of the cipher text, it would
appear that it might be some kind of block cipher (but with the
length dependence already noted). Since the attacker appears able
to do chosen plaintext attacks, I would recommend using strings
of increasing length until block length can be determined.



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