Nonvolatile memory protecting system and method

Abstract

The invention provides nonvolatile memory protecting system and method. The method comprises the following steps of: calling a protecting code from a memory by a control unit; and limiting an unauthorized user to program or verify data/program of a protecting area. Meanwhile, the data input into the memory is encrypted data; the nonvolatile memory protecting system realizes that different memories have different keys, is not limited to one encrypting method and can provide different key protections for different addresses; if the key needs to be modified, the operation is carried out just by programming without replacing hardware; in the invention, an address encrypting key is used for encrypting the memory address, and the data of the unauthorized user for accessing the memory address is scrambling data; and a data/program decrypting key is used for decrypting the data/program of the memory, thereby preventing the unauthorized user from illegally obtaining the data and resolving.

Description

technical field [0001] The invention relates to a protection system and protection method for data / program programming, data / program verification, address encryption and data / program decryption of non-volatile memory. Background technique [0002] The traditional non-volatile memory encryption methods mainly include the following three types: (1) software encryption is performed on the data of the memory through a compiler, and the memory encryption realized by this method is easy to be cracked by analyzing signals and communication protocols; (2) through A hardware encryption module is set in the memory, and the encryption module is implemented by a fixed specific encryption algorithm. The memory encryption realized by this method is not flexible enough, and the same encryption method is used for different memory codes; (3) the key is solidified by masking Inside a ROM memory, if the memory encryption implemented by this method needs to be modified, it must be modified at t...

AI Technical Summary

Problems solved by technology

[0002] The traditional non-volatile memory encryption methods mainly include the following three types: (1) software encryption is performed on the data of the memory through a compiler, and the memory encryption realized by this method is easy to be cracked by analyzing signals and communication protocols; (2) through A hardware encryption module is set in the memory, and the encryption module is implemented by a fixed specific encryption algorithm. The memory encryption realized by this method is not flexible enough, and the same encryption method is used for different memory codes; (3) the key is solidified by masking Inside a ROM memory, if the memory encryption implemented by this method needs to be modified, it must be modified at the chip level. Compared with the second method, the cost of changing the method to modify the encryption key is much smaller, and only the mask can be modified, thereby Change the key, but for mass products, hardware modification cannot use different keys for each product, and key modification requires a certain amount of time and cost

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