Encryption method based on USB interface

Abstract

The invention relates to an encryption method based on a USB interface, which comprises the following steps of: electrifying equipment, electrifying a USB encryption card, re-enumerating a USB and waiting for an instruction; judging whether timing time is up or not; sending, by an upper computer, an SETUP token to the USB encryption card; analyzing, by a USB microcontroller, the token, and selecting, by the upper computer, data and an algorithm for operation according to the wValue and wIndex which are randomly generated; judging whether the instruction code is a control code or not, and if yes, sending the wValue and wIndex to a programmable device; transmitting, by the programmable device, an operation result to the USB microcontroller; transmitting, by the programmable device, an operation result to the USB microcontroller; and comparing, by the upper computer, the operation results, and if the comparison is correct, executing other logic functions. According to the method, a randomnumber is used for generating an encryption effect, the design is simple, a complex encryption algorithm is not needed, but cracking is difficult, and the effect of software protection is effectivelyachieved.

Description

technical field [0001] The invention relates to a USB interface technology, in particular to an encryption method based on the USB interface. Background technique [0002] Due to the differences in the main business and professional fields, cross-development of software and hardware has increasingly become an important way of communication and cooperation between enterprises. Seek to cooperate with another company B in this field for development. A will provide the hardware platform, and B will adapt the software based on the hardware platform. The two companies will fairly allocate project funds according to the workload. This will not only save development costs, but also Shortening the development cycle can also expand the business scope of the enterprise and improve the competitiveness of the enterprise. However, there is a problem in this cooperation method, that is, the infinite copyability of the software may cause enterprise B to be unable to know the delivery quant...

AI Technical Summary

Problems solved by technology

At present, the hardware and software design of USB encryption devices on the market are basically the same. They are mainly composed of USB microcontroller, EEPROM and extended program memory. The encryption algorithm is integrated in the firmware. When the encryption card is powered on, it will be loaded and run by the USB microcontroller. As long as the encryption algorithm is not known, it is difficult to crack it in principle

However, there is a common problem with this method, that is, the openness of the hardware may fundamentally circumvent the limitations of the software, especially the eeprom and the program memory are both readable and writable devices, which are easy to be read and written by the program burner, as long as the user Reading out the binary file in this memory can basically duplicate the function of the encryption card

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