METHOD AND APPARATUS FOR MEMORY ENCRYPTION WITH INTEGRITY CHECK AND PROTECTION AGAINST REPLAY ATTACKS

摘要

A method and apparatus to provide cryptographic integrity checks and replay protection to protect against hardware attacks on system memory is provided. A mode of operation for block ciphers enhances the standard XTS-AES mode of operation to perform memory encryption by extending a tweak to include a “time stamp” indicator. A tree-based replay protection scheme uses standard XTS-AES to encrypt contents of a cache line in the system memory. A Message-Authentication Code (MAC) for the cache line is encrypted using enhanced XTS-AES and a “time stamp” indicator associated with the cache line. The “time stamp indicator” is stored in a processor.