Research On Digital Signature Algorithm For Two-dimensional Code Authentication

Nowadays,two-dimensional codes are more widely used in the fields of social networking,payment services,and promotion of public accounts.As a new technology of data storage and information transmission,two-dimensional codes have the advantages of greater data storage,more data types can representde and not restricted by the database.However,with the open and convenient application mode of two-dimensional code,various types of information security issues also frequently occur.An improved RSA(Rivest-Shamir-Adleman)digital signature algorithm is proposed in this thesis,which combines the idea of hybrid security key algorithm based on four prime number and the Chinese remainder optimized RS A algorithm,which is used in QR(Quickly Resespons)code authentication,it can retain the symbolic characteristics of QR codes without any modifiation of the original information.Then,in view of the lack of confidentiality of information in the process of QR code authentication,a confidential QR code authentication scheme is proposed.The scheme uses a hybrid encryption algorithm generated by the combination of the improved AES(Advanced Encryption Standard)algorithm and RSA algorithm to encrypt QR information.Finally,this thesis discusses the feasibility and advantages of a special digital signature algorithm,that is,multiple digital signature algorithms,and proposes an efficient structured multiple digital signature two-dimensional code authentication scheme.(1)In view of the RSA algorithm is easy to be attacked by factorization and its running speed is slow under high bits keys,an improved RSA digital signature algorithm is proposed.Combining with the requirement of digital signature algorithm for two-dimensional code authentication technology,the most widely used RSA digital signature algorithm is improved in this thesis.This algorithm combines the idea of hybrid security key algorithm and Chinese remainder,first,the hybrid security key algorithm based on four prime numbers is applied to the digital signature,not only does it reduce the number of key bits to improve the efficiency of the operation,but also achieves the purpose of resisting the modulus decomposition attack by replacing the modulus with a random number,second,the Chinese remainder is used to simplify the signature operation process,which is speeding up the computational efficiency further,finally,the security of the algorithm is analyzed through common RSA digital signature algorithm attack methods,and the efficiency of the algorithm is compared through experiments.(2)Considering that the QR code that uses the RSA digital signature algorithm for authentication does not have the function of information confidentiality,a confidential QR code authentication scheme is proposed,on the basis of guaranteeing the authentication of the two-dimensional code,it paid more attention to the protection of information.The scheme is divided into two parts:encryption and signature.The encryption part combines the improved AES algorithm and the improved RSA algorithm to generate a hybrid encryption algorithm:first it uses the improved AES algorithm to encrypt the plaintext information,and then use the improved RSA algorithm to encrypt the relevant parameters in the AES algorithm.At the same time,the AES algorithm is improved from key expansion and column confusion transformation to speed up the encryption and decryption rate of the AES algorithm.The signature part extracts the information digest from the encrypted ciphertext and parameter ciphertext,and then uses the improved RSA digital signature algorithm to digitally sign the information digest,finally generates a confidential and verifiable QR code according to the QR code standard encoding.This scheme adopts the order of first encryption and then signature,which satisfies the verification requirement of QR code information disclosure.(3)In order to meet the need for secure,orderly and fair signatures of QR codes during transportation,and ensure the integrity,verifiability and non-repudiation of multiple authentication of QR code information,analysis of multiple digital signature algorithms applied to QR codes because the feasibility and advantages of certification technology.First,an efficient broadcast multiple digital signature algorithm based on the identity RSA algorithm is improved.The improved algorithm can resist the attack of the signature multiplier by stealing the identity of the initiator of the signature,and then stealing the broadcast multiple digital signature results.Based on the algorithm idea this thesis proposes an order-based multiple digital signature algorithm and a structured multiple digital signature algorithm,finally gives an application scheme of identity-based RSA structured multiple digital signature in two-dimensional code authentication,the performance and efficiency analysis of the algorithm is given through theoretical and experimental comparison.