Integrity Of The PLC Firmware Enhancement Method Based On MD5

The security of industrial control system have been followed closely along with the rapiddevelopment of the network communication technique，the biggest concern is field devicessafely run，such as the programmable controller(PLC) is direct control and monitor fieldapparatus, so the safety and reliability of the PLC is a hot area for research control system.With the title of "Integrity of the PLC Firmware Enhancement Method Based on MD5，，，thethesis is studies the integrity verification technology of PLC use in control system, while thefirmware baseline intercepted during transmission，to enhance integrity of the PLC firmware.This method not only to apply the PLC, and it can be spread to any firmware embeddedsystems, so the thesis research has great significance to promote the embedded systemreliability of machinery and equipment.This paper analyses the enhancement technique of the firmware integrity and thedomestic and foreign research progress of hash algorithm, researches the mechanism andmethods of Trusted Computing’ s completeness, build a architecture, what is integrity of PLCfirmware based on the MD5algorithm, proposes a new way of the ifrmware baselineintercepted based on analyst firmware transmission characteristic, and integrity of PLCfirmware checking method based on the MD5algorithm, integrities verification sotfware andplatform was developed, integrities verification experiment and contrast experiment isdesigned.The main contributions of this paper are listed as follows:(1)This thesis makes a research on the design theory and technology of the trustedcomputing，the relationships between trusted computing and integrity assurance are analysis,applied it to the PLC firmware integrity verification, propose a architecture of PLC firmwareintegrity method based on the MD5algorithm;(2)This thesis set the unstructured binary code of the firmware and characteristics oftransfer protocol as a research object，data extraction and establish baseline of the firmwarewas discussed; (3)A virtual platform of PLC was constructed by intercept the data，transmit data of PLCfirmware between the computer and the computer, check integrity of the PLC firmware asstandard baseline, this article creatively points out we can intercept the data by simulating thePLC, MD5algorithm was applied to the validation process, which was regarded as very goodintermediate technology, in order to avoid wrong judgment，and increase creditability process;(4)The integrity of PLC firmware test platform is designed based on the MD5algorithm，it can achieve platform sotfware functions, through the Microsoft Visual Studio2008integrated development tools, and create applications by C#programming language. Testresult was found by four contrast test, include complete test，or the data increase or reduce，replace data of the firmware.Test shows that，integrity of the PLC firmware enhancement method based on MD5wasdesigned in this paper, which was original and can test the integrity of firmware accurately, themethod not only to validate terminal control of PLC eiffciently，but it also provided a usefulway for other embedded control system.