Hackers teach you how to crack software

Software cracking-questions about how to track programs:

When beginners start to learn decryption, they often don't know how to track the program, how to find a place where the registration code is compared, and how to feel overwhelmed when facing a long pile of program code. Generally, software programs use a sub-program called CALL ********* to verify whether the entered registration code is correct or not. For programs with an explicit registration code, generally, the entered registration code and the correct registration code are put into the Register, and then the verification subroutine is called to judge and return the result. The application determines whether the registration is successful based on the result returned by the subroutine, such a program often has the following forms:

 
 

  
  
*****: ********* Mov eax, [**********] or push eax)
  
  
 
  
  
* *****: ********* Mov edx, [**********], or push edx)
  
  
 
  
  
*****: ********** CALL ********
  
  
 
  
  
* *****: ********* Test eax, EAX, or test al, AL, or none of the other forms)
  
  
 
  
  
* *****: ********** JNZ ********* or JZ)
 
 

The memory areas pointed by EAX and EDX are the registration code we entered and the correct registration code. The registers EAX and EDX here are written at will, or ECX, EBX, EDI, ESI and so on. For programs with an implicit registration code, although the correct registration code cannot be directly seen, the entered Registration Code address is usually first put into a register, and then the subroutine is called for verification, when cracking, you need to go to the subroutine to analyze and register the algorithm.

In short, we can see the subprogram call *******) followed by the jump command JNZ ********* or JZ ********) we should be vigilant when using d eax or EBX, ECX, EDX, EDI, ESI... wait) to see what is hidden in the memory area pointed to by the register. One thing you should note: You should note that the following function is used in the program, that is, GetDlgItenInt. The function of this API is to convert the input text to an integer, therefore, this type of program will not display the existing registration code, because the registration code is converted to an integer, the program usually uses cmp ecx, EDX this type of command to verify the correctness of the registration code, here, ECX and EDX are stored in the integer form of the entered registration code and correct registration code. Can we use it now? Edx and? Ecx is in decimal format, that is, the input format.

Anti-installation of software: we often encounter a problem when using some software, that is, after the Shared Software expires, even if the original program is deleted and re-installed, the program is still unavailable, we also remind you that the trial period has passed, please register; or you have cracked a software, but want to continue to study it, but because the software has been registered, there is no registration option, at this time, even if you completely delete the program and re-install the software, the program will still be registered after the program runs. In this case, the reason is actually very simple, because the program will register or expiration information in the system registry, so simple re-installation of software is useless. The solution is to delete the information related to the Registry by yourself. However, because the registry is the basis of the work of the WINDOWS system, if you are not careful, it may damage the registry and cause system exceptions, therefore, if you are not familiar with the Registry, back up the registry before modification.

You can use the registry management tool "REGEDIT" in WINDOWS to modify or back up the Registry. One way is to enter "regedit" under "start-> Run" to start it, you can also click "C: \ WINDOWS \ regedit.exe" to run it. Most applications store their own information in the following path: HKEY_LOCAL_MACHINE \ Software, HKEY_LOCAL_MACHINE \ Software \ Microsoft, HKEY_CURRENT_USER \ Software, HKEY_CURRENT_USER \ Software \ Microsoft or HKEY_USERS \. in DEFAULT \ Software, the specific place varies according to different programs. As long as the keys related to the application are found in the above order, delete the key values related to the user name and registration code. BitsCN_com

Software cracking-questions about cracking exercises:

Learning to crack requires a lot of exercises. For the choice of cracking targets, Beginners should not aim at large-sized and well-known software, because these software usually has complicated encryption and is difficult to crack, we recommend that you use small-sized and earlier shared software that is not well-known for practice, because the relatively simple encryption software helps beginners quickly master the ideas and skills of cracking. The source of exercises is extensive. You can download them from the Internet or purchase some shared software CDs on the market.

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Hackers teach you how to crack software

Hackers teach you how to crack software