US Patent 11989320 Hidden electronic file system within non-hidden electronic file system

Systems and method for creating a hidden electronic file system within a non-hidden electronic file system are provided. Files within a non-hidden electronic file system are pre-allocated and populated with a number of payload blocks, a first portion of which include user data to be covertly stored, a second portion of which include directory information pointing to first portion of payload blocks, and a third portion of which is configured for use as free and available space for new or replacement data. Each of a number of cipher blocks comprise random numbers to be used as a cipher for a corresponding one of the number of payload blocks. Each of the payload blocks is encrypted by an associated one of the cipher blocks.