breakx.cpp

此为本书的配套光盘.本书不但由浅入深地讲解了软件保护技术

/********************************************************************

	Copyright (c) Beijing Feitian Technologies
	http://www.FTSafe.com

	File :		BreakX.cpp	

	Created:	2003/11/05

	Author:		yihai
	
	Purpose:	?

	Revision:	?

*********************************************************************/
// BreakX.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"

#include <Windows.h>

void Branch2_Func1();
void Branch2_Func2();
void Branch2_Func3();

void Branch1_Func1();
void Branch1_Func2();
void Branch1_Func3();

void FuncEntry();

#pragma optimize( "", off ) 	
void Throw_Div0()
{
	printf("(Throw_Div0)\n");
	int i=0;	
	i /=i;
}
#pragma optimize( "", on ) 

void Throw_ErrIns()
{	 
	printf("(Throw_ErrIns)\n");
	__asm  _emit 0x8d
	__asm  _emit 0xc0
}

void Throw_Addr0()
{
	printf("(Throw_Addr0)\n");
	char* p = (char*)NULL;
	*p = (char)GetTickCount();
}

void Throw_Addr0_asm()
{
	printf("(Throw_Addr0_asm)\n");
	__asm  xor eax,eax
	__asm  mov eax,[eax]
}

void Branch1_Func1()
{
	printf("Branch1_Func1\n");
	__try
	{
		Branch1_Func2();
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		printf("catch exception Branch1_Func1\n");
		Throw_Div0();
	}	
}

void Branch1_Func2()
{
	printf("\tBranch1_Func2\n");
	__try
	{
		Branch1_Func3();		
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		printf("\tcatch exception Branch1_Func2\n");
		Throw_Addr0();
	}
}

typedef struct _EXCEPTION_REGISTRATION_RECORD
{
    struct _EXCEPTION_REGISTRATION_RECORD * pNext;
    FARPROC                                 pfnHandler;
} EXCEPTION_REGISTRATION_RECORD, *PEXCEPTION_REGISTRATION_RECORD;

PEXCEPTION_REGISTRATION_RECORD  g_pSaveNextRec=NULL;

void my_except_handler()
{
	printf("my_except_handler\n");

	__asm mov eax,g_pSaveNextRec
	__asm mov fs:[0],eax

	Throw_Addr0_asm();
}

void BreakXHandler(PEXCEPTION_REGISTRATION_RECORD  pRec)
{		
	PEXCEPTION_REGISTRATION_RECORD  pNextRec=0;	
	__asm mov eax,fs:[0]
	__asm mov pNextRec,eax
		
	__asm mov eax,pRec
	__asm mov fs:[0],eax
		
	g_pSaveNextRec = pNextRec;	
	
	pRec->pNext = (PEXCEPTION_REGISTRATION_RECORD)-1;
	pRec->pfnHandler = (FARPROC)my_except_handler;	
}

void Branch1_Func3()
{
	EXCEPTION_REGISTRATION_RECORD  eRec;
	printf("\t\tBranch1_Func3\n");
	__try
	{			
		BreakXHandler(&eRec);		
		MessageBox(0,"xList has been broken",0,0);
		Throw_ErrIns();		
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		printf("\t\tcatch exception Branch1_Func3\n");
		Throw_Addr0_asm();
	}
}


void Branch2_Func1()
{
	printf("Branch2_Func1\n");
	__try
	{
		Branch2_Func2();
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		printf("catch exception Branch2_Func1\n");
		Throw_Div0();
	}	
}

void Branch2_Func2()
{
	printf("\tBranch2_Func2\n");
	__try
	{
		Branch2_Func3();		
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		printf("\tcatch exception Branch2_Func2\n");
		Throw_Addr0();
	}
}

void Branch2_Func3()
{
	printf("\t\tBranch2_Func3\n");
	__try
	{
		Throw_ErrIns();
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		printf("\t\tcatch exception Branch2_Func3\n");
		printf("\t\tcall FuncEntry now\n");
		FuncEntry();
	}
}

void FuncEntry()
{
	MessageBox(NULL,"Function is Normal",NULL,MB_OK);
}

int main(int argc, char* argv[])
{
	__try
	{
		Branch1_Func1();
	}
	__except(EXCEPTION_EXECUTE_HANDLER)
	{
		Branch2_Func1();
	}
	
	return 0;
}