On the McEliece Public-Key Cryptosystem

Based on an idea by Hin, the method of obtaining the original message after selecting k of n coordinates at random in the McEliece public-key cryptosystem is improved. The attack, which is more efficient than the attacks previously proposed, is characterized by a systematic method of checking and by a random bit swapping procedure. An optimization procedure similar to the one proposed by Lee and Brickell is used to improve the attack. The attack is highly suitable for parallel and pipelined implementation. The work factor and the values, which yield ‘maximum’ security for the system are given. It is shown that the public-key can be reduced to k x (n-k) bits.