Hook example - time

main.cpp

#include <ctime>
#include <iostream>
using namespace std;

int main() {
        time_t t = time(0);   // get time now
        struct tm * now = localtime( & t );
        int year = now->tm_year + 1900;
        int month = now->tm_mon + 1;
        int day = now->tm_mday;

        if ( month == 12 && day == 24) {
                cout << "The pass is: XmassTree" <<endl;
                return 0;
        }
        cout << "Today is: " << year << '-'
                << month << '-'
                <<  day
                << ", wait for Christmass Eve to get the password!" <<endl;

#ifdef _WINDOWS
	system("pause");
#endif
	
	return 0;
}

parrot.asm

.686
.model flat,c
option casemap:none

include windows.inc
include user32.inc
include kernel32.inc
includelib user32.lib
includelib kernel32.lib

.data
AppName			db "DLL Skeleton",0
HelloMsg		db "Hello, you're calling a function in this DLL",0
LoadMsg			db "The DLL is loaded",0
UnloadMsg		db "The DLL is unloaded",0
ThreadCreated	db "A thread is created in this process",0
ThreadDestroyed db "A thread is destroyed in this process",0

.code
DllEntry proc hInstance:HINSTANCE, reason:DWORD, reserved1:DWORD
	.if reason==DLL_PROCESS_ATTACH
		invoke MessageBox,NULL,addr LoadMsg,addr AppName,MB_OK
	.elseif reason==DLL_PROCESS_DETACH
		invoke MessageBox,NULL,addr UnloadMsg,addr AppName,MB_OK
	.elseif reason==DLL_THREAD_ATTACH
		invoke MessageBox,NULL,addr ThreadCreated,addr AppName,MB_OK
	.else        ; DLL_THREAD_DETACH
		invoke MessageBox,NULL,addr ThreadDestroyed,addr AppName,MB_OK
	.endif
	mov  eax,TRUE
	ret
DllEntry Endp
_repeat proc param1:DWORD
	mov eax, 549AD8F4h
	ret	
_repeat endp
End DllEntry

parrot.def

LIBRARY parrot
EXPORTS _repeat