vmassembler is a small C++ project which uses [flex](https://en.wikipedia.org/wiki/Flex_(lexical_analyser_generator)) and [bison](https://www.gnu.org/software/bison/manual/) to parse `.vasm` files and assemble virtual instructions. The project inherits [vmprofiler](https://githacks.org/vmp2/vmprofiler) which is used to identify vm handler's, provide them with a name, immidate value size, and other meta data to aid in assembling virtual instructions.
In order to use the virtual instruction assembler you must first have a few values at hand. You must have an unpacked vmprotect 2 binary. This file cannot be a dump, it must be unpacked. Second, you must know the RVA to the vm entry address of the first push instruction. This first push instruction must not be `push contant_value`, it must be of type `push reg` as the constant values are pushed onto the stack by the generated c++ header file. The last thing you need is a virtual instruction assembly file. You can make one of these easily. Simply open a text editor and create your first label:
***Note: you can use ANY virtual instruction which is defined by vmprofiler... you can see them all [here](https://githacks.org/vmp2/vmprofiler/-/tree/a419fa4633f98e2f819b1119dc0884154e207482/src/vmprofiles)***
Once you have defined a vasm file, you can now generate the c++ header file which will handle everything for you. Simply execute the following command:
```
vmassembler.exe --input [filename] --vmpbin [vmprotect'ed binary] --vmentry [make sure this rva is correct!] --out test.hpp
```
If the file is generated without any errors you can now include this file inside of your project. This header file uses no STL, nor any CRT functions, however it does create a RWX section so if you want to use this in a driver it cannot run on HVCI systems...
To call your vasm routine all you must do is pass the label name as a template param...
