Security within integrated circuits

摘要

A method for hindering detection of information unintentionally leaked from a secret held in a memory unit is described, the method including receiving a triggering event waiting for at least a first amount of time to pass after the receipt of the triggering event, the memory unit being in a non-operational state during the at least a first amount of time after the at least a first amount of time has passed, changing at least one first condition under which the memory unit operates, thereby causing the memory unit to enter an operational state, waiting for a second amount of time to pass after the changing at least one first condition, and changing, after the second amount of time, at least one second condition under which the memory unit operates, thereby causing the memory unit to enter the non-operational state, wherein access to the secret information is enabled only during the second amount of time, and detection of secret information unintentionally leaked is limited during the first amount of time. Related apparatus and methods are also described.

主权项

1. A machine-implemented method for hindering detection of secret information unintentionally leaked from a secret held in a memory unit, the method comprising:
storing the secret information in a location within the memory unit; episodically re-deriving the secret information by performing the following:
retrieving a first key from a location in a second memory unit;generating a second key;performing one of: decrypting the secret information with the first key and encrypting it with the second key; and deobfuscating the secret information with the first key and obfuscating it again with the second key; andstoring the second key in the second location in memory; and storing the re-derived secret information at the location within the memory unit, wherein the episodic re-deriving of the secret information causes an episodic change of physical contents of the memory unit holding the secret information, thereby causing the secret information unintentionally leaked from the memory unit to vary over time causing any detector of leaked information requiring long collection times which are longer than feasible to receive an average of the leaked information, the average of the leaked information not revealing the leaked information.