Research on a Novel Hashing Stream Cipher

A stream cipher namely the HSC (hashing stream cipher) which uses a regular one-way hash function to generate pseudorandom keystream iteratively is proposed. Since the timestamp is used in the keystream generator, the algorithm achieves the robustness against the adaptive-chosen-plaintext attack. The oneway hash function is the core of the algorithm, so the security analysis of the algorithm is shifted to that of the hash function. If the core one-way hash function is chosen properly, it can be asserted that there would be no period in the HSC keystream. Firstly the algorithm was introduced detailedly. Then its applying security and efficiency respectively discussed deeply. The experimental result shows that the algorithm has both a high security and good efficiency