The Research And Apply Of Program Protection Technique

Software as a form of computer data, can be arbitraily used by copy, duplicate, etc.The use of unauthorized software can bring economic loss to society, so before releaseof the software, software protection is a necessary stage. In software protection, mostare suitable for the PE format executable file, from the file structures and executioncharacteristics for protection. The main purpose of the software protection is to hinderPE debugger to debug, handicap the malicious user, reverser analysis program algorithmand organizational structure, etc.Shell Protection technology is processing the whole code and data to encryption,compression, and then add a new section “shell Section”, which is used to save Shellcode and key data, etc. There are many unsafe factors in the packers’s protectiontechnology, shell information obvious, after the recovery process, the code and datastored in the clear form, import table is too obvious and so on.This thesis is aiming at analysing the shortcomings of the shell protection software,and then put forward the improvement scheme to increase software protection efforts.This thesis proposes a new protection model, which is to protect the obj files. The newprotection model has a detailed research for the protection technology of the PE and objfile. The protection software is protected from the cost of the debugging and the reverseengineering. In this thesis, the main research content as follows:1. Research the executable file formats, obj file format and their execution processon Windows platform. Research the menthod and the matters needing attention ofgenerated PE file and obj file format.2. Research and apply software encryption and compression technology. In thesystem, use polymorphic encryption engine and random password. Add hardwareencryption mechanism to encrypt the software, such as making U disk serial number asthe encrypted keys. Choose a variety of compression algorithm to protect program. Thegood compression algorithm can improve the efficiency of program running andprotection. 3. Improvement of shell protection technology. Shell protection software generallyusing code, data, and resources as the basic units for encryption, compression, This wayof encryption is easy for malicious users to write scripts to crack, and eventually makesthe software to restore the original form. In order to have a better protection software,this thesis slices the code into smaller segments, and than encrypts and compresses thecode. Decrypting and decompressing the data when run the program.4. New protection model. Protect obj file, link protection obj files are generated toprotectd PE file. Protection measures can be used to the code and data of the obj file.Anti debugging and anti tracking technology integrated into the recover code. The newmodel can improve the protection code stability and improve the protection strength.