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es3n1n/injector.cpp

Last active December 3, 2023 15:42
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LoadLibraryA (LLA) injector
Raw
injector.cpp
#include "injector.h"
#include <TlHelp32.h>
#include <stdio.h>
#define INJECTOR_FAIL(s) { printf(s " Error code: %d\n", GetLastError( ) ); return false; }
namespace injector {
namespace detail {
bool fixed_csgo = false;
void* get_process_by_name( const wchar_t* name ) {
void* thSnapShot = CreateToolhelp32Snapshot( TH32CS_SNAPPROCESS, 0 );
if ( thSnapShot == INVALID_HANDLE_VALUE )
return nullptr;
PROCESSENTRY32W pe;
pe.dwSize = sizeof( PROCESSENTRY32W );
unsigned long ret = 0;
for ( bool proc = Process32FirstW( thSnapShot, &pe ); proc; proc = Process32NextW( thSnapShot, &pe ) ) {
if ( wcscmp( pe.szExeFile, name ) )
continue;
ret = pe.th32ProcessID;
break;
}
CloseHandle( thSnapShot );
return ret ? OpenProcess( PROCESS_ALL_ACCESS, false, ret ) : nullptr;
}
}
bool inject( const wchar_t* proc, const char* path ) {
HANDLE proc_handle = detail::get_process_by_name( proc );
if ( !detail::fixed_csgo && proc_handle && !wcscmp( proc, L"csgo.exe" ) ) {
HMODULE ntdll = GetModuleHandleW( L"ntdll.dll" );
if ( !ntdll )
INJECTOR_FAIL( "csgo patcher: Failed to find ntdll module." );
void* load_dll = GetProcAddress( ntdll, "LdrLoadDll" );
void* open_file = GetProcAddress( ntdll, "NtOpenFile" );
if ( !load_dll || !open_file )
INJECTOR_FAIL( "csgo patcher: Failed to find functions to patch." );
WriteProcessMemory( proc_handle, load_dll, load_dll, 10, nullptr );
WriteProcessMemory( proc_handle, open_file, open_file, 10, nullptr );
detail::fixed_csgo = true;
}
return ::injector::inject( proc_handle, path );
}
bool inject( HANDLE proc, const char* path ) {
if ( !proc )
INJECTOR_FAIL( "Failed to open a process. Make sure injector is running as an admin." );
char full_path[ 260 ];
if ( !GetFullPathNameA( path, sizeof( full_path ), full_path, nullptr ) )
INJECTOR_FAIL( "Failed to find a dll." );
HMODULE kernel32 = GetModuleHandleW( L"kernel32.dll" );
if ( !kernel32 )
INJECTOR_FAIL( "Failed to get kernel32.dll handle." );
void* lla = reinterpret_cast< void* >( GetProcAddress( kernel32, "LoadLibraryA" ) );
if ( !lla )
INJECTOR_FAIL( "Failed to find LoadLibraryA function." );
void* str = VirtualAllocEx( proc, nullptr, strlen( full_path ), MEM_RESERVE | MEM_COMMIT, PAGE_EXECUTE_READWRITE );
if ( !str )
INJECTOR_FAIL( "Failed to allocate memory region for str." );
WriteProcessMemory( proc, str, full_path, strlen( full_path ), nullptr );
CreateRemoteThread( proc, nullptr, 0, reinterpret_cast< LPTHREAD_START_ROUTINE >( lla ), str, 0, nullptr );
CloseHandle( proc );
return true;
}
}
#undef INJECTOR_FAIL
Raw
injector.h
#pragma once
#include <Windows.h>
namespace injector {
namespace detail {
extern bool fixed_csgo;
void* get_process_by_name( const wchar_t* name );
}
bool inject( const wchar_t* proc, const char* path );
bool inject( HANDLE proc, const char* path );
}
Raw
main.cpp
#include "injector/injector.h"
int main( ) {
if ( !injector::inject( L"csgo.exe", "bruh.dll" ) )
system( "pause" );
return EXIT_SUCCESS;
}
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