Hello,
My scenario is as follows:
I have a program that generates ciphertext, message-hash, key pair, (RSA) and I need to model a simple attack.
Everything is fine, but one of the attacks I am having trouble with: I need to somehow 'modify' the byte array containing the ciphertext and prove that the receiver of the message propper will be able to detect the interference.
Whats the best way to do this though? if I access elements like:
array[4] = (byte) 0x0;
then I run into 'data must start with a zero' padding errors. Which, although alerting the receiver to a problem, avoids the true aim of my test, -hash authentication.
My only workaround in mind is to have this 'adversary' create his own cipher from scratch based on his own message.
Thanks in advance,
Matt