Research On Security Mechanism Of Embedded System Based On Authentication And Digital Watermark

With the progress of Internet and communication technology,most embedded systems have the function of network communication.However,the openness of the network makes the embedded system vulnerable to all kinds of attacks.This poses a significant security risk to many basic activities that rely on embedded systems to perform important control tasks.Therefore,security has become an urgent issue to be solved for embedded systems in an open environment.Aiming at the security problem of embedded systems in an open environment,this paper designs an identity authentication protocol that adds user biometric information and uses lightweight functions,and implements a digital watermarking technology to prevent sensitive data from being tampered inside the system.The method ensures that the system can not only resist the attacks of illegal users,but also defend against tampering attacks by legitimate users.The detailed works of the paper is as follows:1.Aiming at the problem that the embedded system in the open environment is vulnerable to illegal users,a lightweight biometric-based authentication protocol is proposed.The protocol compensates for the drawbacks of traditional two-factor authentication protocols based on passwords and smart cards that are not resistant to dictionary attacks and easy to lose by adding biometric information that has the advantages of no memory,hard to steal and difficult to imitate.By adopting the lightweight function based on hash operations,bitwise XOR operations,and fuzzy extractor functions reduces the computational resources consumed by the embedded system to execute the authentication protocol.In addition,the session key generated in the protocol can be used to encrypt the transmitted data,thus ensuring the confidentiality and integrity of the data.In this paper,the formal verification and informal security analysis of the protocol are compared with other related protocols.The results show that the protocol can not only resist the attacks of illegal users,but also eliminate the security vulnerabilities and functions of existing protocols,while reducing the costs of computing and communication.2.A digital watermarking technology based on FLASH memory is proposed for the identity authentication protocol,which can not resist the tampering attack of the legitimate user on the device,thus causing the legitimate user to profit from tampering with sensitive data.This technology uses non-volatile FLASH memory,sector-based erasure,the merit that write operation can only change the "1" in the storage unit to "0",some identification information(namely,digital watermark information)can be directly embedded in the FLASH memory of the embedded device,So that legitimate users can not falsify the watermark information to achieve the goal of the attack.Based on this technology,the current use time of the device and the user's authentication parameters can be installed in the same sector of FLASH memory as a digital watermark.Take an instance,where a legal user tampers with the data in order to prolong the use of time in the smart detection of the embedded system of high-speed rail catenary.The results show that this method can effectively prevent legitimate users from manipulating the cumulative use time to break through the limitation of the length of usage of the system.