US Patent 7809130 Password recovery system and method

A system, method and computer program product for recovering a password including, for each possible password to be tested, generating a periodicity unit based on a number of symbols in the password and a size of a chunk used by a one-way function to encrypt the password. The periodicity unit is substantially shorter than an input string, that includes replicated actual password used to encrypt the password. Based on the periodicity unit, using the one-way function, generating a control value for the periodicity unit. The control value is tested for a match with a control value generated from the actual password. An indication of a match is provided to a user.