Patent ID: 7596704
Filing Date: 2009-09-29
Classification: H04L

Abstract:
1. A method for protecting a digital secret, comprising: transforming a user-selected password, which is independent of a digital secret to be protected, into a temporary value by a first transformation; using the temporary value and the digital secret as inputs to a second transformation to produce a secret-dependent digital segment in a transitory memory; storing the secret-dependent digital segment in a persistent memory; deleting the secret-dependent digital segment from the transitory memory; deleting the digital secret and the temporary value from each memory associated with computations of the first and second transformations; receiving a password and a secret-dependent segment from a user requesting the recovery of the digital secret; without a prior validation of the received password, using the received password and the received secret-dependent digital segment as inputs to a third transformation to compute a value as a recovered secret; validating the recovered secret with verification information that has a relationship with the digital secret; and determining whether the received password matches the selected password and whether the received secret-dependent digital segment matches the secret-dependent digital segment according to an outcome of the validating step, wherein the first and second transformations are configured, respectively, as a first function ƒ wherein the first, the second, and the third functions are as follows: (1) U=ƒ (2)V=ƒ (3) S=ƒ