/*
-----------------------------------------------------------------------------
* Created by * lallous <lallousx86@yahoo.com> *
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE
LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
OF
* SUCH DAMAGE.
*
-----------------------------------------------------------------------------
*/
// IsInsideVPC's exception filter
DWORD __forceinline IsInsideVPC_exceptionFilter(LPEXCEPTION_POINTERS ep)
{
PCONTEXT ctx = ep->ContextRecord;
ctx->Ebx = -1; // Not running VPC
ctx->Eip += 4; // skip past the "call VPC" opcodes
return EXCEPTION_CONTINUE_EXECUTION;
// we can safely resume execution since we skipped faulty instruction
}
// high level language friendly version of IsInsideVPC()
bool IsInsideVPC()
{
bool rc = false;
__try
{
_asm push ebx
_asm mov ebx, 0 // Flag
_asm mov eax, 1 // VPC function number
// call VPC
_asm __emit 0Fh
_asm __emit 3Fh
_asm __emit 07h
_asm __emit 0Bh
_asm test ebx, ebx
_asm setz [rc]
_asm pop ebx
}
// The except block shouldn't get triggered if VPC is running!!
__except(IsInsideVPC_exceptionFilter(GetExceptionInformation()))
{
}
return rc;
}
