wince.c

cryptlib安全工具包

/****************************************************************************
*																			*
*						WinCE Randomness-Gathering Code						*
*						Copyright Peter Gutmann 1996-2005					*
*																			*
****************************************************************************/

/* This module is part of the cryptlib continuously seeded pseudorandom number
   generator.  For usage conditions, see random.c */

/* General includes */

#include "crypt.h"
#include "random/random.h"

/* OS-specific includes */

#include <tlhelp32.h>

/* The size of the intermediate buffer used to accumulate polled data */

#define RANDOM_BUFSIZE	4096

/* Handles to various randomness objects */

static HANDLE hToolHelp32;	/* Handle to Toolhelp.library */
static HANDLE hThread;		/* Background polling thread handle */
static DWORD threadID;		/* Background polling thread ID */

/****************************************************************************
*																			*
*									Fast Poll								*
*																			*
****************************************************************************/

/* Type definitions for function pointers to call CE native functions */

typedef BOOL ( *CEGENRANDOM )( DWORD dwLen, BYTE *pbBuffer );
typedef DWORD ( *GETSYSTEMPOWERSTATUS )( PSYSTEM_POWER_STATUS_EX2 pSystemPowerStatusEx2,
										 DWORD dwLen, BOOL fUpdate );

/* The shared Win32 fast poll routine */

void fastPoll( void )
	{
	static BOOLEAN addedFixedItems = FALSE;
	static BOOLEAN hasAdvFeatures = FALSE, hasHardwareRNG = FALSE;
	static CEGENRANDOM pCeGenRandom = NULL;
	static GETSYSTEMPOWERSTATUS pGetSystemPowerStatusEx2 = NULL;
	FILETIME  creationTime, exitTime, kernelTime, userTime;
	LARGE_INTEGER performanceCount;
	SYSTEM_POWER_STATUS_EX2 powerStatus;
	MEMORYSTATUS memoryStatus;
	HANDLE handle;
	POINT point;
	RANDOM_STATE randomState;
	BYTE buffer[ RANDOM_BUFSIZE ];
	int bufIndex = 0, length;

	if( krnlIsExiting() )
		return;

	/* Initialize the native function pointers if necessary.  CeGetRandom()
	   is only available in relatively new versions of WinCE, so we have to
	   link it dynamically */
	if( pCeGenRandom == NULL )
		{
		HANDLE hCoreDLL;

		if( ( hCoreDLL = GetModuleHandle( TEXT( "Coredll.dll" ) ) ) != NULL )
			pCeGenRandom = ( CEGENRANDOM ) GetProcAddress( hCoreDLL, TEXT( "CeGenRandom" ) );
		}
	if( pGetSystemPowerStatusEx2 == NULL )
		{
		HANDLE hGetpower;

		if( ( hGetpower = GetModuleHandle( TEXT( "Getpower.dll" ) ) ) != NULL )
			pGetSystemPowerStatusEx2 = ( GETSYSTEMPOWERSTATUS ) \
							GetProcAddress( hGetpower, TEXT( "GetSystemPowerStatusEx2" ) );
		}

	initRandomData( randomState, buffer, RANDOM_BUFSIZE );

	/* Get various basic pieces of system information: Handle of active
	   window, handle of window with mouse capture, handle of clipboard owner
	   handle of start of clpboard viewer list, pseudohandle of current
	   process, current process ID, pseudohandle of current thread, current
	   thread ID, handle of desktop window, handle  of window with keyboard
	   focus, whether system queue has any events, cursor position for last
	   message, 1 ms time for last message, handle of window with clipboard
	   open, handle of process heap, handle of procs window station, types of
	   events in input queue, and milliseconds since Windows was started */
	addRandomValue( randomState, GetActiveWindow() );
	addRandomValue( randomState, GetCapture() );
	addRandomValue( randomState, GetCaretBlinkTime() );
	addRandomValue( randomState, GetClipboardOwner() );
	addRandomValue( randomState, GetCurrentProcess() );
	addRandomValue( randomState, GetCurrentProcessId() );
	addRandomValue( randomState, GetCurrentThread() );
	addRandomValue( randomState, GetCurrentThreadId() );
	addRandomValue( randomState, GetDesktopWindow() );
	addRandomValue( randomState, GetDC( NULL ) );
	addRandomValue( randomState, GetDoubleClickTime() );
	addRandomValue( randomState, GetFocus() );
	addRandomValue( randomState, GetForegroundWindow() );
	addRandomValue( randomState, GetMessagePos() );
	addRandomValue( randomState, GetOpenClipboardWindow() );
	addRandomValue( randomState, GetProcessHeap() );
	addRandomValue( randomState, GetQueueStatus( QS_ALLINPUT ) );
	addRandomValue( randomState, GetTickCount() );
	if( krnlIsExiting() )
		return;

	/* Get multiword system information: Current caret position, current
	   mouse cursor position */
	GetCaretPos( &point );
	addRandomData( randomState, &point, sizeof( POINT ) );
	GetCursorPos( &point );
	addRandomData( randomState, &point, sizeof( POINT ) );

	/* Get percent of memory in use, bytes of physical memory, bytes of free
	   physical memory, bytes in paging file, free bytes in paging file, user
	   bytes of address space, and free user bytes */
	memoryStatus.dwLength = sizeof( MEMORYSTATUS );
	GlobalMemoryStatus( &memoryStatus );
	addRandomData( randomState, &memoryStatus, sizeof( MEMORYSTATUS ) );

	/* Get thread and process creation time, exit time, time in kernel mode,
	   and time in user mode in 100ns intervals */
	handle = GetCurrentThread();
	GetThreadTimes( handle, &creationTime, &exitTime, &kernelTime, &userTime );
	addRandomData( randomState, &creationTime, sizeof( FILETIME ) );
	addRandomData( randomState, &exitTime, sizeof( FILETIME ) );
	addRandomData( randomState, &kernelTime, sizeof( FILETIME ) );
	addRandomData( randomState, &userTime, sizeof( FILETIME ) );

	/* Get extended battery/power status information.  We set the fUpdate
	   flag to force a re-read of fresh data rather than a re-use of cached
	   information */
	if( pGetSystemPowerStatusEx2 != NULL && \
		( length = \
				pGetSystemPowerStatusEx2( &powerStatus,
										  sizeof( SYSTEM_POWER_STATUS_EX2 ),
										  TRUE ) ) > 0 )
		addRandomData( randomState, &powerStatus, length );

	/* Get random data provided by the OS.  Since this is expected to be
	   provided by the system vendor, it's quite likely to be the usual
	   process ID + time */
	if( pCeGenRandom != NULL )
		{
		BYTE randomBuffer[ 32 ];

		if( pCeGenRandom( 32, randomBuffer ) )
			addRandomData( randomState, randomBuffer, 32 );
		}

	/* The following are fixed for the lifetime of the process so we only
	   add them once */
	if( !addedFixedItems )
		{
		SYSTEM_INFO systemInfo;

		GetSystemInfo( &systemInfo );
		addRandomData( randomState, &systemInfo, sizeof( SYSTEM_INFO ) );
		addedFixedItems = TRUE;
		}

	/* The performance of QPC varies depending on the architecture it's
	   running on, and is completely platform-dependant.  If there's no
	   hardware performance counter available, it uses the 1ms system timer,
	   although usually there's some form of hardware timer available.
	   Since there may be no correlation, or only a weak correlation,
	   between the performance counter and the system clock, we get the
	   time from both sources */
	if( QueryPerformanceCounter( &performanceCount ) )
		addRandomData( randomState, &performanceCount,
					   sizeof( LARGE_INTEGER ) );
	addRandomValue( randomState, GetTickCount() );

	/* Flush any remaining data through.  Quality = int( 33 1/3 % ) */
	endRandomData( randomState, 34 );
	}

/****************************************************************************
*																			*
*									Slow Poll								*
*																			*
****************************************************************************/

/* Type definitions for function pointers to call Toolhelp32 functions */

typedef BOOL ( WINAPI *MODULEWALK )( HANDLE hSnapshot, LPMODULEENTRY32 lpme );
typedef BOOL ( WINAPI *THREADWALK )( HANDLE hSnapshot, LPTHREADENTRY32 lpte );
typedef BOOL ( WINAPI *PROCESSWALK )( HANDLE hSnapshot, LPPROCESSENTRY32 lppe );
typedef BOOL ( WINAPI *HEAPLISTWALK )( HANDLE hSnapshot, LPHEAPLIST32 lphl );
typedef BOOL ( WINAPI *HEAPFIRST )( HANDLE hSnapshot, LPHEAPENTRY32 lphe,
									DWORD th32ProcessID, DWORD th32HeapID );
typedef BOOL ( WINAPI *HEAPNEXT )( HANDLE hSnapshot, LPHEAPENTRY32 lphe );
typedef HANDLE ( WINAPI *CREATESNAPSHOT )( DWORD dwFlags, DWORD th32ProcessID );
typedef BOOL ( WINAPI *CLOSESNAPSHOT )( HANDLE hSnapshot );

/* Global function pointers. These are necessary because the functions need to
   be dynamically linked since only some WinCE builds contain them */

static CREATESNAPSHOT pCreateToolhelp32Snapshot = NULL;
static CLOSESNAPSHOT pCloseToolhelp32Snapshot = NULL;
static MODULEWALK pModule32First = NULL;
static MODULEWALK pModule32Next = NULL;
static PROCESSWALK pProcess32First = NULL;
static PROCESSWALK pProcess32Next = NULL;
static THREADWALK pThread32First = NULL;
static THREADWALK pThread32Next = NULL;
static HEAPLISTWALK pHeap32ListFirst = NULL;
static HEAPLISTWALK pHeap32ListNext = NULL;
static HEAPFIRST pHeap32First = NULL;
static HEAPNEXT pHeap32Next = NULL;

/* Since there are a significant number of ToolHelp data blocks, we use a
   larger-than-usual intermediate buffer to cut down on kernel traffic */

#define BIG_RANDOM_BUFSIZE	( RANDOM_BUFSIZE * 4 )

static void slowPollWinCE( void )
	{
	PROCESSENTRY32 pe32;
	THREADENTRY32 te32;
	MODULEENTRY32 me32;
	HEAPLIST32 hl32;
	HANDLE hSnapshot;
	RANDOM_STATE randomState;
	BYTE buffer[ BIG_RANDOM_BUFSIZE ];
	int bufIndex = 0, listCount = 0, iterationCount;

	/* Initialize the Toolhelp32 function pointers if necessary.  The
	   Toolhelp DLL isn't always present (some OEMs omit it) so we have to
	   link it dynamically */
	if( hToolHelp32 == NULL )
		{
		/* Obtain the module handle of the kernel to retrieve the addresses
		   of the ToolHelp32 functions */
		if( ( hToolHelp32 = LoadLibrary( TEXT( "Toolhelp.dll" ) ) ) == NULL )
			{
			/* There's no ToolHelp32 available, now we're in a bit of a
			   bind.  Try for at least a fast poll */
			fastPoll();
			return;
			}

		/* Now get pointers to the functions */
		pCreateToolhelp32Snapshot = ( CREATESNAPSHOT ) GetProcAddress( hToolHelp32, TEXT( "CreateToolhelp32Snapshot" ) );
		pCloseToolhelp32Snapshot = ( CLOSESNAPSHOT ) GetProcAddress( hToolHelp32, TEXT( "CloseToolhelp32Snapshot" ) );
		pModule32First = ( MODULEWALK ) GetProcAddress( hToolHelp32, TEXT( "Module32First" ) );
		pModule32Next = ( MODULEWALK ) GetProcAddress( hToolHelp32, TEXT( "Module32Next" ) );
		pProcess32First = ( PROCESSWALK ) GetProcAddress( hToolHelp32, TEXT( "Process32First" ) );
		pProcess32Next = ( PROCESSWALK ) GetProcAddress( hToolHelp32, TEXT( "Process32Next" ) );
		pThread32First = ( THREADWALK ) GetProcAddress( hToolHelp32, TEXT( "Thread32First" ) );
		pThread32Next = ( THREADWALK ) GetProcAddress( hToolHelp32, TEXT( "Thread32Next" ) );
		pHeap32ListFirst = ( HEAPLISTWALK ) GetProcAddress( hToolHelp32, TEXT( "Heap32ListFirst" ) );
		pHeap32ListNext = ( HEAPLISTWALK ) GetProcAddress( hToolHelp32, TEXT( "Heap32ListNext" ) );
		pHeap32First = ( HEAPFIRST ) GetProcAddress( hToolHelp32, TEXT( "Heap32First" ) );
		pHeap32Next = ( HEAPNEXT ) GetProcAddress( hToolHelp32, TEXT( "Heap32Next" ) );