ENCRYPTION OF STREAMS OF ADDRESSED INFORMATION TO BE USED FOR PROGRAM CODE PROTECTION

摘要

The present invention relates to an encryption method for selecting any byte of data stored in a particular on-chip memory as an encryption key. This selected byte is then used to encrypt itself and all remaining data in that particular memory. The selected bytes do not have values specifically assigned for encryption and they are selected from the body of data to be encrypted only according to certain rules.;When this technique is implemented, each byte of data stored in the memory is combined with one of the designated cryptographic key bytes (eg, using an exclusive NOR gate) before being published. There is no need for separate supply, program or safety measures. Also, no silicon area is wasted for storing such bytes. An attacker would need some part of the original data to decrypt the result of this cryptographic technique. In addition, these technologies deteriorate gracefully. The key is chosen such that the encrypted data does not have a single common dependency. Thus, if a single key is found, only a very small portion of the encrypted data is found.