lobstr

Cross platform minimal and fast hooking library with useful extensions

Dependencies

This project depends on capstone. Make sure you have correctly installed it and that the required header and library are available for your compiler.

Building

1. Get the source
   • git clone https://github.com/ptrstr/lobstr
2. Configure project
   • cd lobstr/build
   • cmake ..
3. Build

   • Linux

     • make

     • sudo make install

       Use this option to install the library

   • Windows

     You will need to build the dll with Visual Studio with the provided .sln file

Using

This project was made to be as easy as possible to use. Here is an example:

#include <lobstr/lobstr.h>
#include <stdio.h>

void integerPrinter(int value) {
  printf("Your modified? integer: %d\n", value);
}

void (*originalIntegerPrinter)(int);
void hookedIntegerPrinter(int value) {
  printf("Custom printing integer: ~~%d~~\n", value);
  // Modfication of `value` and callback
  value = 1337;
  originalIntegerPrinter(value);
}

int main(int argc, char *argv[]) {
  originalIntegerPrinter = &integerPrinter;

  // Returns NULL on error
  hook_t *hook = allocHook((void *)hookedIntegerPrinter, (void **)&originalIntegerPrinter);
  if (!hook)
    return 1;

  integerPrinter(55);

  freeHook(hook);

  return 0;
}

Output:

Custom printing integer: ~~55~~
Your modified? integer: 1337