Given plaintext: P[i], i = 1..N
Given stream of cryptographic numbers S[i, j], i = 1..N, S[i, j] in [1, j] generated by RC5 for example
We encrypt using Fisher-Yates shuffle algorithm:
for (int i = N, i > 1 ; i--) swap(P[i], S[i, i])
How to estimate complexity of breaking such chipher?
Is it lower than strength of S[i] generator?
How does it depend on value of N?
How does it depend on data we encrypt?
Unfortunately I was unable to find anything useful on topic.
P.S. Why not AES? Because chipertext is harder to detect using frequency analysis.