In the field of computing, program packing refers to executing a “pack” program before the original program runs, and then handing the program back to the original program. The benefit of this approach is that the true entry point (OEP) of the executable program cannot be easily found through conventional cracking methods, effectively preventing the cracking of the source program and protecting important information data.
Pack Encryption
Pack encryption can be divided into various types such as disguise pack and compressed pack. Although the implementation details of packing methods differ, their core encryption principle remains unchanged, which is to establish a separate protective mechanism outside the original program. Therefore, regardless of whether the source program has been compressed, encrypted, or had its addresses scrambled, the complete source code must still be restored to function properly. This presents a security risk with pack encryption, as it can be bypassed or stripped by many unpacking tools. Currently, there are many free unpacking tools available online that can easily perform unpacking operations, making it unwise to rely solely on packing to protect the source program.
Another slight drawback of pack encryption is the compatibility issue. Differences in executable files across different system platforms lead to varying requirements for packing. For example, executable files under DOS are suitable for files ending in .COM, which have no file header, and the default program execution address is 0x100; on the win32 platform, PE files do not support self-loading and require the program to manage data using its own methods, leading to a lack of standardization and making the compatibility issue of pack encryption difficult to resolve.
Algorithm Porting Solutions
In addition to pack encryption, another popular PC software encryption method in the market is algorithm porting solutions. The basic principle is to port a portion of the code functionality from the executable file to run on another secure hardware platform, ensuring that the original program code remains incomplete. The advantage of this approach is that both the existing program and the ported program must be cracked together to achieve true cracking. For this encryption solution, the secure hardware platform outside the PC is very important, with the most common being algorithm porting dongles, which typically use highly secure embedded security chips to execute the ported code. Since security chips have numerous anti-cracking mechanisms, the code running inside cannot be illegally read out. As long as the ported code is selected reasonably, it can greatly enhance the security of the executable software.
However, this software encryption solution also has its drawbacks; it requires developers to have a certain level of embedded programming capability, and the research and development time investment will be relatively high.
Both of the aforementioned encryption solutions have their own advantages and disadvantages. Users need to combine their actual needs and application scenarios to choose the appropriate encryption solution. If users prioritize security, then the algorithm porting dongle will be more suitable.
