Description
An RC4 state is a 256 bytes states with two 8-bit index pointers i and j denoted by (S ,i ,j) The initial RC4 state is generated by KSA demoted by( S0, i=0, j=0).
An important feature of RCA is that the RC4 state is revertible That is, if (S* , i*, j*)=PRGAn (S ,i, j) it has (S ,i, j)=IPRGAn (S* , i*, j*)Where PRGAn demotes applying n rounds PRGA (samefor IPRGAn) and IPRGA is the reverse algorithm of PRGA. This feature means that any former
RC4 state can be recovered from a later RC4 state by applying certain rounds IPRGA.Write code to implementboth the PRGA algorithm and following IPRGA algorithm and design and implement a way confirm that any RC4 state can go forward by PRGA and backward by IPRGA.
IPRGA(S, i , j)
Generation loop;
S[i] ⟷ S[j]
j←(j-S[i ] +256)mod 256
i←(i -1)mod 256
Unformatted Attachment Preview
Purchase answer to see full attachment
Explanation & Answer
Review
Review
24/7 Homework Help
Stuck on a homework question? Our verified tutors can answer all questions, from basic math to advanced rocket science!
Similar Content
Related Tags
The Unwinding of the Miracle
by Julie Yip-Williams
The Visible Filth
by Nathan Ballingrud
Epic of Gilgamesh
by Unknown
The Age of Innocence
by Edith Wharton
The English Patient
by Michael Ondaatje
Crime and Punishment
by Fyodor Dostoyevsky
Principles - Life and Work
by Ray Dalio
Macbeth
by William Shakespeare
Persuasion
by Jane Austen