Method, system and medium for analog encryption in a flash memory

摘要

A system and method for analog encryption and decryption, in which the encryption and encoding processes are interrelated, such that by failing to decrypt the retrieved data, decryption fails.

主权项

1. A method performed by a system that comprises hardware elements, the method comprising:
encrypting input data using a base key and an auxiliary key, wherein decryption of the encrypted input data requires the auxiliary key, and wherein the auxiliary key is only recoverable based on obtaining encrypted input data containing no errors; modifying programming thresholds and incremental stepped pulse programming (ISPP) size of a Flash memory to increase a number of errors due to retention; and storing the encrypted input data in the Flash memory; wherein the encrypting of the input data comprises: generating cipher data by performing a logical exclusive OR (XOR) operation on a key stream and an input data stream, wherein the key stream is dependent on a first encoding function; generating intermediate encoded cipher data based on a second encoding function performed on the cipher data; and generating final encoded cipher data based on the intermediate encoded cipher data and a result of the first encoding function; wherein the method further comprises generating the key stream by: performing the first encoding function on the base key to generate a codeword; using the codeword to generate the auxiliary key and syndrome values; performing a logical exclusive OR (XOR) operation on the auxiliary key and a cipher key to obtain a combined key; and using the combined key to generate the key stream.