mirror of https://github.com/tongzx/nt5src
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
92 lines
2.5 KiB
92 lines
2.5 KiB
/***
|
|
*seccinit.c - initialize the global buffer overrun security cookie
|
|
*
|
|
* Copyright (c) 2000-2001, Microsoft Corporation. All rights reserved.
|
|
*
|
|
*Purpose:
|
|
* Define __security_init_cookie, which is called at startup to initialize
|
|
* the global buffer overrun security cookie used by the /GS compile flag.
|
|
*
|
|
* NOTE: The ATLMINCRT library includes a version of this file. If any
|
|
* changes are made here, they should be duplicated in the ATL version.
|
|
*
|
|
*Revision History:
|
|
* 01-24-00 PML Created.
|
|
* 09-16-00 PML Make sure cookie never initialized to zero (vs7#162619)
|
|
* 09-20-00 PML Use a better cookie initialization (vs7#165188)
|
|
*
|
|
*******************************************************************************/
|
|
|
|
#include <internal.h>
|
|
#include <windows.h>
|
|
|
|
/*
|
|
* The global security cookie. This name is known to the compiler.
|
|
*/
|
|
extern DWORD_PTR __security_cookie;
|
|
|
|
/*
|
|
* Union to facilitate converting from FILETIME to unsigned __int64
|
|
*/
|
|
typedef union {
|
|
unsigned __int64 ft_scalar;
|
|
FILETIME ft_struct;
|
|
} FT;
|
|
|
|
/***
|
|
*__security_init_cookie(cookie) - init buffer overrun security cookie.
|
|
*
|
|
*Purpose:
|
|
* Initialize the global buffer overrun security cookie which is used by
|
|
* the /GS compile switch to detect overwrites to local array variables
|
|
* the potentially corrupt the return address. This routine is called
|
|
* at EXE/DLL startup.
|
|
*
|
|
*Entry:
|
|
*
|
|
*Exit:
|
|
*
|
|
*Exceptions:
|
|
*
|
|
*******************************************************************************/
|
|
|
|
void __cdecl __security_init_cookie(void)
|
|
{
|
|
DWORD_PTR cookie;
|
|
FT systime;
|
|
LARGE_INTEGER perfctr;
|
|
|
|
/*
|
|
* Initialize the global cookie with an unpredictable value which is
|
|
* different for each module in a process. Combine a number of sources
|
|
* of randomness.
|
|
*/
|
|
|
|
GetSystemTimeAsFileTime(&systime.ft_struct);
|
|
#if !defined(_WIN64)
|
|
cookie = systime.ft_struct.dwLowDateTime;
|
|
cookie ^= systime.ft_struct.dwHighDateTime;
|
|
#else
|
|
cookie = systime.ft_scalar;
|
|
#endif
|
|
|
|
cookie ^= GetCurrentProcessId();
|
|
cookie ^= GetCurrentThreadId();
|
|
cookie ^= GetTickCount();
|
|
|
|
QueryPerformanceCounter(&perfctr);
|
|
#if !defined(_WIN64)
|
|
cookie ^= perfctr.LowPart;
|
|
cookie ^= perfctr.HighPart;
|
|
#else
|
|
cookie ^= perfctr.QuadPart;
|
|
#endif
|
|
|
|
/*
|
|
* Make sure the global cookie is never initialized to zero, since in that
|
|
* case an overrun which sets the local cookie and return address to the
|
|
* same value would go undetected.
|
|
*/
|
|
|
|
__security_cookie = cookie ? cookie : 0xBB40E64E;
|
|
}
|