Hello guys could anyone tell me the problem with my DLL, unable to get WM_xxx messages:
very simple app:
.586
.model flat,stdcall
option casemap:none
include masm32rt.inc
WinMain PROTO hInst:HINSTANCE,hPrevInst:HINSTANCE,CmdLine:LPSTR,CmdShow:DWORD
.data
ClassName db "MainWinClass",0
AppName db "Main Window",0
hInstance HINSTANCE 0
clsbutton db "button",0
sethook db "Set hook",0
button1 db "button1",0
button2 db "button2",0
clsedit db "edit",0
edit1 db "edit1",0
edit2 db "edit2",0
mydll db "dll.dll",0
exp db "SetMyHook",0
.code
; ---------------------------------------------------------------------------
start:
invoke GetModuleHandle, NULL
mov hInstance,eax
invoke WinMain, hInstance,NULL,NULL,SW_SHOWDEFAULT
invoke ExitProcess,eax
WinMain proc hInst:HINSTANCE,hPrevInst:HINSTANCE,CmdLine:LPSTR,CmdShow:DWORD
LOCAL wc:WNDCLASSEX
LOCAL msg:MSG
LOCAL hwnd:HWND
mov wc.cbSize,SIZEOF WNDCLASSEX
mov wc.style, CS_HREDRAW or CS_VREDRAW
mov wc.lpfnWndProc, OFFSET WndProc
mov wc.cbClsExtra,NULL
mov wc.cbWndExtra,NULL
push hInstance
pop wc.hInstance
mov wc.hbrBackground,COLOR_BTNFACE+1
mov wc.lpszMenuName,NULL
mov wc.lpszClassName,OFFSET ClassName
invoke LoadIcon,NULL,IDI_APPLICATION
mov wc.hIcon,eax
mov wc.hIconSm,eax
invoke LoadCursor,NULL,IDC_ARROW
mov wc.hCursor,eax
invoke RegisterClassEx, addr wc
INVOKE CreateWindowEx,NULL,ADDR ClassName,ADDR AppName,\
WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 600, 200, NULL, NULL, hInstance, NULL
mov hwnd,eax
invoke ShowWindow, hwnd,SW_SHOWNORMAL
invoke UpdateWindow, hwnd
.WHILE TRUE
invoke GetMessage, ADDR msg,NULL,0,0
.BREAK .IF (!eax)
invoke TranslateMessage, ADDR msg
invoke DispatchMessage, ADDR msg
.ENDW
mov eax,msg.wParam
ret
WinMain endp
WndProc proc hWnd:HWND, uMsg:UINT, wParam:WPARAM, lParam:LPARAM
LOCAL ps:PAINTSTRUCT
.IF uMsg==WM_DESTROY
invoke PostQuitMessage,NULL
.ELSEIF uMsg==WM_CREATE
invoke CreateWindowEx,NULL,addr clsbutton,addr sethook,WS_CHILD or WS_VISIBLE,250,100,100,50,hWnd,1,hInstance,NULL
invoke CreateWindowEx,NULL,addr clsbutton,addr button1,WS_CHILD or WS_VISIBLE,10,10,100,80,hWnd,10,hInstance,NULL
invoke CreateWindowEx,NULL,addr clsbutton,addr button2,WS_CHILD or WS_VISIBLE,110,10,100,80,hWnd,20,hInstance,NULL
invoke CreateWindowEx,NULL,addr clsedit,addr edit1,WS_CHILD or WS_VISIBLE or WS_BORDER,210,10,100,80,hWnd,30,hInstance,NULL
invoke CreateWindowEx,NULL,addr clsedit,addr edit2,WS_CHILD or WS_VISIBLE or WS_BORDER,310,10,100,80,hWnd,40,hInstance,NULL
.ELSEIF uMsg==WM_COMMAND
mov ax,word ptr wParam
.if ax == 1
invoke LoadLibrary,addr mydll
.if eax != 0
; get address of the exported function
invoke GetProcAddress,eax,addr exp
.if eax != 0
call eax ; set hook
.endif
.endif
.endif
.ELSE
invoke DefWindowProc,hWnd,uMsg,wParam,lParam
ret
.ENDIF
xor eax,eax
ret
WndProc endp
end start
DLL:
.386
.model flat,stdcall
include masm32rt.inc
CallWndProc PROTO nCode:UINT, wParam:WPARAM , lParam:LPARAM
.data
hInstance HINSTANCE 0
hWndProcHook dd 0
sWM_CREATE db "WM_CREATE",0
sWM_COMMAND db "WM_COMMAND",0
sWM_CHAR db "WM_CHAR",0
sWM_KEYDOWN db "WM_KEYDOWN",0
sWM_MOUSEMOVE db "WM_MOUSEMOVE",0
.code
DllEntry proc hInst:HINSTANCE, reason:DWORD, reserved1:DWORD
mov eax, hInst
mov hInstance, eax
mov eax, TRUE
ret
DllEntry Endp
SetMyHook proc
invoke SetWindowsHookEx,WH_CALLWNDPROC,CallWndProc,hInstance,0
mov hWndProcHook,eax
xor eax,eax
ret
SetMyHook endp
CallWndProc proc nCode:UINT, wParam:WPARAM , lParam:LPARAM
.if nCode == HC_ACTION
mov edi,lParam
; for some reason assume is not working here, i don't why
.if dword ptr [edi+8] == WM_CREATE
invoke OutputDebugString,addr sWM_CREATE
.elseif dword ptr [edi+8] == WM_COMMAND
invoke OutputDebugString,addr sWM_COMMAND
.elseif dword ptr [edi+8] == WM_CHAR
invoke OutputDebugString,addr sWM_CHAR
.elseif dword ptr [edi+8] == WM_KEYDOWN
invoke OutputDebugString,addr sWM_KEYDOWN
.elseif dword ptr [edi+8] == WM_MOUSEMOVE
invoke OutputDebugString,addr sWM_MOUSEMOVE
.endif
.endif
invoke CallNextHookEx,hWndProcHook, nCode, wParam, lParam
ret
CallWndProc endp
end DllEntry
Perhaps if you told us what you are trying to do with a DLL trying to hook system messages, then we may be able to help you.
Quote from: hutch-- on August 23, 2014, 05:02:44 PM
Perhaps if you told us what you are trying to do with a DLL trying to hook system messages, then we may be able to help you.
Trying to capture messages of all controls in the application using a DLL ( Only for an application, which will load the DLL. ).
App code is just a test simulating controls ( The controls messages that I want to capture ). the DLL code is not capturing messages :icon_confused: