Design And Implementation Of 7-zip File Cracking System Based On GPU

With the development of information and improvement of security awareness,people pay more attention to the safety of stored information.In the investigation process,it's common to decipher the encrypted data information,while promoting the use and development of different decryption software.When it comes to the processing power and memory bandwidth,GPU is far superior to CPU of the same period,which greatly enhances the efficiency of file crack.In this case,the use of GPU for cracking and restoring various encrypted filed has been continuously studied.This paper will choose GPU with CUDA to design system and improve the efficiency of cracking encrypted 7-Zip files.The main work of this paper is as follows:1.This paper points out the application scenarious of GPU decryption with examples and proposes exisiting decryption algorithm based on GPU.Current main decryption software does not support the password recovery of 7-Zip files,which obviously cannot meet the needs of electronic evidence of relevant departments.Therefore,this paper designes a GPU-based 7-Zip password cracking system to efficiently restore the contents before compression and encryption.2.Before designing and implenmenting this proposal,this paper analyzes the structure of 7-Zip file and gives detailed instructions of file format and file content with examples based on 7-Zip binaries.Meanwhile,the process of 7-Zip file encryption is also presented and analysezd.3.This paper designs and implements a GPU-based system to recover password of 7-Zip files.It uses AES-256 algorithm,SHA256 algorithm and CRC algorithm to crack password files brutally.The password cracking model is divided into seven modules:the command-line parsing module,cipher extracting module,password generation module,password verification module,extracting modules,CRC check module and status output module.The specific design implementation of the seven modules is presented in this paper.4.In addition to implementing the system password cracking on the Windows platform,this paper also carries out the porting system,so that the system can be achieved in the Linux platform as well.By building cross-platform development environment and porting the code,the system can be implemented in different platforms.5.Test results are given in this paper.On the Windows platform,the speed of password checking can reach 6867 per second,while the speed of password cracking on the Linux platform can reach 7631 per second.The system is able to restore the encrypted 7-Zip files of different forms quickly on different platforms.In this paper,we not only offer the schemes in theory but also give the specific code implementation and analysis of results.This research is of great significance for practical applications like network security and new computer forensics.