Analysis And Analysis Of Several Authentication Encryption Algorithms

Modern cryptography has drawn much attention and highly recognition as a basis for information security and it has become the hottest spot of the modern cryptography research. The authenticated encryption mode is a kind of cryptographic scheme to solve the practical problems such as the privacy and authenticity of the user's information by encrypting the message and calculating the authentication tag. The CAESAR competition is a new competition calling for submissions of authenticated ciphers in May 2014. The competition has collected 57 authenticated encryption algorithms which most of the algorithms are based on the block cipher. LAC and Tiaoxin-346 are two classical algorithms and have been submitted to the competition. A detailed analysis for the two algorithms is made in this paper. The main work for solving this problem is as follows:Firstly, the authenticated encryption scheme is introduced in detail, which include general structure, classification method and security analysis of the scheme. We make research in deep by the authenticated encryption algorithm based on block cipher, such as ALE. We also analyze an attack method which called leaked-state-forgery attack(LSFA) against ALE, and mastered the attack idea of LSFA.Secondly, a deep research is carried on the authenticated encryption algorithm LAC. The LAC algorithm is analyzed by the differential analysis of the block cipher LBlock-s and the attack thought of LSFA attack against ALE. And then a differential trail to exist local collision and algorithm example are shown in this paper.Finally, a depth study about the authentication encryption algorithm Tiaoxin-346 is conducted and a security analysis is made on this algorithm. Then a new search method to search differential trail is proposed, this method is applied to search two differential trails which matched the condition. The experiment result shows that the probabilities are improved obviously compared with the existing algorithms.