Research And Implementation Of Attack Defensive DES Circuit

Over last decade or so in computer science development,It’s become more and more important in secure asset protection,cryptographic algorithms implementation and protection.The attack and protect of chip design implementation is an extensive field in industry.There are many kinds of attack methods for cryptographic algorithms,Differential Fault Analysis（DFA）is a powerful cryptanalytic technique that disturbs cryptographic computations and exploits erroneous results to infer secret keys.In this thesis,we describe and adopt a fault model by introducing some faults and address Data Encryption Standard（DES）issue and recover its key.Then offer two anti-attack hardware implementation scheme.In this thesis,we analyze algorithm structure,decompose every rounds computation process,construct the fault model,target the last few rounds to introduce faults,and finally obtained secret keys.According to this fault model,using large number of encrypt results to distinguish and analyze useful data,exploiting correctness results and erroneous results,to infer DES secret keys.Cipher block like DES demonstrate the vulnerability towards DFA,A straightforward way to protect any algorithm against DFA is to compute it twice,include redundancy and coherence checking circuit at the operation level and check whether the obtained results are equal or not.However,this method takes too many resources in design implementation.This paper put forward two another protection scheme.One is pseudo-operation which makes attacker cannot easily be aligned with power consumption profile,so as hard to find the last few rounds position to realize attack.Another solution is Error Detection Code（EDC）which implement in sensitive rounds and data verifying the integrity.Upon fault attack,the verify of integrity will indicate error,makes algorithms return a specify results to the attacker make him impossible to get the valid erroneous results to do DFA.