RC4 Algorithm And Its Security Analysis

The RC4 algorithm is a stream cipher with a variable-length key, which was designed by Ron Rivest for RSA Data Security Corporation in 1987. Due to high security and efficient software implementation, the design idea of RC4 differs from that of other stream ciphers. It has been widely used in the commercial products, including Lotus Notes,AOCE of Apple computer and Oracle Secure SQL database and many other applications.As it is used so widely, RC4 has turned to be one of important research fields. This paper is to introduce this algorithm and analyze its security. There have been many kinds of attacks on RC4 at present, which are represented in chapter 3.Our main result is introduction of a new fault induction attack on RC4. Fault induction attacks can be practical in certain extent, and all kinds of techniques of fault induction are developing. So the analysis in this way on RC4 has certain research sense. The new fault induction attack in this paper consists of Algorithm 1 and Algorithm 2, aiming at revealing the whole initial states of RC4. The algorithm 1 is one round attack on RC4, which can get 3 entries of the initial state: S 0[1],S 0[ n ] and S 0 [ j1 ]. The algorithm 2 is the whole 256 rounds attack on RC4, which can almost reveal the whole initial states of RC4 with less than 216 bytes of stream and less than 216 fault inductions.Another result is as follow. About 203 entries of S0 can be revealed with the possibility of 63.3% by the above attack after 214 to 215 fault inductions. The rest 53 entries of the initial state can be revealed efficiently with the complexity of 214.13 combining with Knudsen's attack.