Research Of Encryption U Disk Based On Chinese Encryption Algorithm

With the rapid development of information technology,data storage and exchange application becomes more and more frequently.The security of data storage is becoming more important.Although the common USB disk has the advantages of portable and affordable,it has great risk of data storage security.Since the data storage on USB disk without authentication and encryption algorithm for protection,the result will be very serious when USB disk is lost or stolen.The foreign encryption algorithm for data storage may have the risk of exist backdoor or at cracked method.In order to solve the above data storage security problem,a security USB disk based on Chinese SM4 encryption algorithm is developed in this dissertation.It adopts domestic self-developed USB2.0 security USB2.0 controller.A keypad microcontroller and circuits is designed for hardware authentication.Embedded multimedia card(eMMC)is designed for data storage medium because it's high performance and capacity.The USB2.0 and eMMC specification is mentioned in this dissertation.The architecture/hardware/firmware design for security USB disk with S261 USB2.0 controller is detail discussed in this dissertation.The firmware of the encryption USB disk includes three parts: SUP firmware,CHP firmware and PIC firmware.SUP firmware is responsible for communication with host USB interface,calling SM4 to encrypt and decrypt data.CHP firmware is responsible for controlling eMMC and receiving SUP commands.The Ping-Pong data transfer strategy is adopted to improve read/write performance of encryption USB disk.PIC firmware implements the keypad input and user authentication operation.The limited password retry strategy is adopted to protect the data storage on encryption USB disk against evil attack.Finally,the functional or performance testing results indicate meet the design goals.The security USB disk has been used and verified at customer market.