i am trying to work on easyhook in python and here is my code
# Hook/EasyHook.py
from ctypes import *
from ctypes.util import find_library
from pathlib import Path
c_ulong_p = POINTER(c_ulong)
c_void_pp=POINTER(c_void_p)
res_path = str(Path(__file__).parent / 'res' / 'EasyHook64.dll')
lib_path = find_library(res_path)
clib = cdll.LoadLibrary(lib_path)
class TRACED_HOOK_HANDLE(Structure):
_fields_ = [("Link", c_void_p)]
lh_install_hook = clib.LhInstallHook
lh_install_hook.restype = c_ulong
lh_install_hook.argtypes = [c_void_p, c_void_p, c_void_p, TRACED_HOOK_HANDLE]
# some definition of other functions...
if __name__ == '__main__':
from ctypes.wintypes import *
t_dll = CDLL('User32.dll')
test=lambda:t_dll.MessageBoxW(None, 'hi content!', 'hi title!', 0)
test()
interface=CFUNCTYPE(c_int, HWND, LPCWSTR, LPCWSTR, UINT)
def fake_function(handle, title, message, flag):
return t_original(handle, "hooked "+title, "hooked "+message, flag)
t_hook_info = TRACED_HOOK_HANDLE(None)
if lh_install_hook(t_dll.MessageBoxW, interface(fake_function), None, byref(t_hook_info)):
raise Exception("Hook error[%s]:\n%s" % (rtl_get_last_error(), rtl_get_last_error_string()))
# error occur here and the program terminate
# some other tests...
after a try, it exit on code 0xC0000005 when running to lh_install_hook
calling and without any exception printed
then I tried to use those Api after inject into a C++ program by
lh_install_hook(func_address, interface(hook_function), None, byref(hook_info))
where func_address
is the actual address of target call,and it cause
python38.dll+24174
_ctypes.pyd+A48D
python38.dll+33E00
python38.dll+3DA6E
_ctypes.pyd+3C69
_ctypes.pyd+38AB
python38.dll+507F5
python38.dll+491C8
is there any way to make it run?
Edit: here is my code inject and run in the c++ programe
# Hook/__init__.py
from .EasyHook import *
class Hook(object):
def __init__(self, func_address: int):
self.enabled = False
self.hook_info = TRACED_HOOK_HANDLE(None)
self._ACLEntries = (c_ulong * 1)(0)
self.ACLEntries = cast(self._ACLEntries, POINTER(c_ulong))
interface = CFUNCTYPE(self.restype, *self.argtypes)
def hook_function(*args):
return self.hook_function(*args)
if lh_install_hook(func_address, interface(hook_function), None, byref(self.hook_info)):
raise LocalHookError()
# error occur here and the program terminate
# some other codes...
restype = c_void_p
argtypes = []
def hook_function(self, *args):
return self.original(*args)
# main.py
from Hook import Hook
from ctypes import *
from ctypes.wintypes import *
class kernel32_beep_hook(Hook):
restype = c_bool
argtypes = [DWORD,DWORD]
def hook_function(self, a1, a2):
if logger is not None:
logger.log('beep_hook','%s,%s'%(a1,a2))
return self.original(a1,a2)
# some skip codes
addr=kernel32.GetProcAddress(kernel32_module,b"Beep")
ctypes.windll.kernel32.Beep(500,500)
hook=kernel32_beep_hook(addr)
# error occur here and the program terminate
According to [GitHub]: EasyHook/EasyHook - (master) EasyHook/Public/easyhook.h:
typedef struct _HOOK_TRACE_INFO_
{
PLOCAL_HOOK_INFO Link;
}HOOK_TRACE_INFO, *TRACED_HOOK_HANDLE;
TRACED_HOOK_HANDLE is actually a pointer (although its name suggests the opposite), therefore your lh_install_hook.argtypes (1st snippet) is incorrect. It should be:
lh_install_hook.argtypes = [c_void_p, c_void_p, c_void_p, POINTER(TRACED_HOOK_HANDLE)]
Technically, you ran into [SO]: C function called from Python via ctypes returns incorrect value (@CristiFati's answer).
Regarding no exception being thrown, maybe [SO]: Python exception thrown by libtidy is amusingly impossible to catch (@CristiFati's answer) should shed some light.
This should get past the problem, at least the main one. I'm not sure whether there are others, as I didn't install (or build) the .lib, so I didn't run your code.
My knowledge is very limited (so this might be complete nonsense), but one potential spot to generate problems is TRACED_HOOK_HANDLE->Link being initialized to NULL.