Research On Password Recovery

The use of passwords in daily life is generally divided into two parts.One is to enter the password for daily Internet access,and the other is for local application software to enter the password.Access to the Internet requires the user to enter various types of passwords.Although the browser can help users record passwords,over time,users will gradually rely on the browser,once you switch to another computer,users often find the password forgotten.A large amount of local software also requires the user to write down a large number of passwords,which in the long run will result in the loss of passwords.For the above two purposes,we mainly divided the study of password recovery into two types.One is based on the off-line encryption file,the other is based on the communication packet.In these two ways,this paper takes KeePass software and Kerberos authentication protocol as the research object respectively.KeePass is an offline password management software that generates a local secret file KDBX for the user's password.By analyzing the data structure of the file,we find out the related fields to verify the password of the user,and then use this field to verify the password recovery software we have written.Kerberos is an identity authentication protocol.By studying RFC related documents and Kerberos official documents,this paper analyzes the authentication process of Kerberos and the user password transformation process,and then uses the grab tool to obtain the encrypted data of the key.After deciphering this part of the data,the combined sub key is performed with the HMAC operation,and the result and density are obtained.The verification code contrast in this paper is used to verify the correctness of the user's password according to the contrast results.Finally,the dictionary enumeration is used to find the user's password in the possible solution space.This paper analyzes the process of password-to-key conversion in KeePass and Kerberos respectively,proposes an improved scheme for Hash functions and AES encryption functions,shortens the conversion time,and thus speeds up password recovery.In addition,this article also adopts GPU parallel acceleration operation based on CUDA platform to further improve the speed of password recovery.