Why reverse engineer a DLL? Sometimes the documentation for a library isn't well written or written at all. If we want to use the DLL, we will need to know how it works. In some aspects, reversing DLLs can be easier than reversing executables because we have the names of the exported functions. In this chapter, we will not only reverse a DLL, but we will write a program that can use it.
You can find the files needed here.
Make sure you have "DLL Entry" breakpoints enabled.
DLLs cannot be executed like executables. To load the DLL, x64dbg will make a little program that will load it. The program will be called something like DLLLoader64_#@@#.exe. You shouldn't have to mess with the DLL loader, I just wanted to let you know so you didn't think you had malware or something on your computer. If x64dbg crashes, you will have to delete the loader executable manually.
I use xAnalyzer and I recommend you do too. When reversing the DLL in this chapter you will want to disable extended and automatic analysis or it will cause a crash. To disable it, start x64dbg and go to Plugins > xAnalyzer. Make sure there is no check mark next to "Extended Analysis" or "Automatic Analysis".