Emulator and method for protecting chip firmware program

Abstract

The invention introduces an emulator and method for protecting chip firmware programs, and relates to the technical field of chip emulation. The emulator includes an emulator control module and emulator hardware, and the emulator hardware includes a chip function debugging module, a register, a stop signal generating module and a chip function module. The emulator control module sets registers through the chip function debugging module, and controls the CPU to stop or run after the chip function module generates a soft reset. The method of protecting the chip firmware program: the emulator control module turns on the soft reset stop function of the emulator hardware, and after running the soft reset command in the chip firmware program, it automatically stops at the first address of the user program area. At this time, the chip firmware program cannot enter the user debugging interface. Access to achieve the purpose of protection. The emulator of the invention realizes the function of automatically switching to the user program area and protecting the chip firmware program, has the characteristics of simple design and convenient use, and provides a code protection scheme for the design of the chip emulator with safety requirements.

Description

technical field [0001] The invention relates to a chip emulator, in particular to an emulator and method for protecting chip firmware programs. Background technique [0002] There will be a chip firmware program in the smart card chip, and the basic function setting and security functions can be realized by executing the program. This program is developed by the chip manufacturer and is protected in the chip, which cannot be accessed through user programs. [0003] For smart card chip emulators, the usual method is to solidify the function settings in the emulator hardware. When the chip updates the function settings, the emulator hardware needs to be redesigned to modify the content of the solidified settings. It is inconvenient to design, implement and maintain. The main problem is There are many differences between this kind of emulator and the real chip, the function settings may be incomplete, the sequence of register operations cannot be controlled, and the boot time ...

AI Technical Summary

Problems solved by technology

[0003] For smart card chip emulators, the usual method is to solidify the function settings in the emulator hardware. When the chip updates the function settings, the emulator hardware needs to be redesigned to modify the content of the solidified settings. It is inconvenient to design, implement and maintain. The main problem is There are many differences between this kind of emulator and the real chip, the function settings may be incomplete, the sequence of register operations cannot be controlled, and the boot time of the user program is inconsistent, etc. There is a risk that the user program will run wrong on the chip after the emulator is debugged.

[0004] Another emulator implementation method is to configure the emulator function through the firmware program, and the emulator control module protects the read, write and debug operations of the chip firmware program. This method makes the software design complicated and difficult to upgrade and maintain.

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