Method and system for encrypting data with an all-or-nothing encryption scheme having additional randomness

摘要

A method for encrypting data for storage on one or more servers includes dividing the data, which includes a first number m of plaintext blocks, into a second number N of equal sized chunks, wherein the second number is based on a number of the servers on which the encrypted data is to be stored, and wherein each chunk includes m/N plaintext blocks. Each of the chunks is encrypted using an all-or-nothing encryption (AONE) scheme so as to output a plurality of ciphertext blocks for each chunk, wherein an additional randomness is embedded into the AONE scheme by an initialization vector derived from the randomness being used as an initial seed for an AONE initialization vector of the AONE scheme. The randomness is encrypted using an XOR-combination of XOR operations performed on the ciphertext blocks for each chunk. The encrypted randomness is stored on each of the servers.