1. A method comprising: determining, by at least one processing device, block digests for blocks of data of an electronic file; encrypting, by the at least one processing device, the blocks of data of the electronic file; determining, by the at least one processing device, a super digest for the electronic file from the block digests; storing, by the at least one processing device, the encrypted blocks of data of the electronic file in a body of an encrypted electronic file; and storing, by the at least one processing device, the super digest in an encrypted portion of a header of the encrypted electronic file.