1. A tangibly embodied computer-readable medium containing computer-executable program instructions, the computer-exectuable program instructions including instructions for: receiving a data file; encrypting the data file; preparing the data file for transmission, the instructions for preparing the data file for transmission including instructions for: decrypting a copy of the encrypted data file; receiving a first internal state from the computer code for decrypting the copy of the encrypted data file; and generating a first validation code by using, at least in part, the first internal state; and transmitting the encrypted data file and the first validation code.