1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
57 /* ====================================================================
58 * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved.
60 * Redistribution and use in source and binary forms, with or without
61 * modification, are permitted provided that the following conditions
64 * 1. Redistributions of source code must retain the above copyright
65 * notice, this list of conditions and the following disclaimer.
67 * 2. Redistributions in binary form must reproduce the above copyright
68 * notice, this list of conditions and the following disclaimer in
69 * the documentation and/or other materials provided with the
72 * 3. All advertising materials mentioning features or use of this
73 * software must display the following acknowledgment:
74 * "This product includes software developed by the OpenSSL Project
75 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
78 * endorse or promote products derived from this software without
79 * prior written permission. For written permission, please contact
80 * openssl-core@openssl.org.
82 * 5. Products derived from this software may not be called "OpenSSL"
83 * nor may "OpenSSL" appear in their names without prior written
84 * permission of the OpenSSL Project.
86 * 6. Redistributions of any form whatsoever must retain the following
88 * "This product includes software developed by the OpenSSL Project
89 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
92 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
93 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
94 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
95 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
96 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
97 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
98 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
99 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
100 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
101 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
102 * OF THE POSSIBILITY OF SUCH DAMAGE.
103 * ====================================================================
105 * This product includes cryptographic software written by Eric Young
106 * (eay@cryptsoft.com). This product includes software written by Tim
107 * Hudson (tjh@cryptsoft.com).
111 #include "internal/cryptlib.h"
112 #include <openssl/rand.h>
113 #include "rand_lcl.h"
115 #if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
116 # include <windows.h>
117 # ifndef _WIN32_WINNT
118 # define _WIN32_WINNT 0x0400
120 # include <wincrypt.h>
121 # include <tlhelp32.h>
124 * Limit the time spent walking through the heap, processes, threads and
125 * modules to a maximum of 1000 milliseconds each, unless CryptoGenRandom
128 # define MAXDELAY 1000
131 * Intel hardware RNG CSP -- available from
132 * http://developer.intel.com/design/security/rng/redist_license.htm
134 # define PROV_INTEL_SEC 22
135 # define INTEL_DEF_PROV L"Intel Hardware Cryptographic Service Provider"
137 static void readtimer(void);
138 static void readscreen(void);
141 * It appears like CURSORINFO, PCURSORINFO and LPCURSORINFO are only defined
142 * when WINVER is 0x0500 and up, which currently only happens on Win2000.
143 * Unfortunately, those are typedefs, so they're a little bit difficult to
144 * detect properly. On the other hand, the macro CURSOR_SHOWING is defined
145 * within the same conditional, so it can be use to detect the absence of
149 # ifndef CURSOR_SHOWING
151 * Information about the global cursor.
153 typedef struct tagCURSORINFO {
158 } CURSORINFO, *PCURSORINFO, *LPCURSORINFO;
160 # define CURSOR_SHOWING 0x00000001
161 # endif /* CURSOR_SHOWING */
163 # if !defined(OPENSSL_SYS_WINCE)
164 typedef BOOL(WINAPI *CRYPTACQUIRECONTEXTW) (HCRYPTPROV *, LPCWSTR, LPCWSTR,
166 typedef BOOL(WINAPI *CRYPTGENRANDOM) (HCRYPTPROV, DWORD, BYTE *);
167 typedef BOOL(WINAPI *CRYPTRELEASECONTEXT) (HCRYPTPROV, DWORD);
169 typedef HWND(WINAPI *GETFOREGROUNDWINDOW) (VOID);
170 typedef BOOL(WINAPI *GETCURSORINFO) (PCURSORINFO);
171 typedef DWORD(WINAPI *GETQUEUESTATUS) (UINT);
173 typedef HANDLE(WINAPI *CREATETOOLHELP32SNAPSHOT) (DWORD, DWORD);
174 typedef BOOL(WINAPI *CLOSETOOLHELP32SNAPSHOT) (HANDLE);
175 typedef BOOL(WINAPI *HEAP32FIRST) (LPHEAPENTRY32, DWORD, size_t);
176 typedef BOOL(WINAPI *HEAP32NEXT) (LPHEAPENTRY32);
177 typedef BOOL(WINAPI *HEAP32LIST) (HANDLE, LPHEAPLIST32);
178 typedef BOOL(WINAPI *PROCESS32) (HANDLE, LPPROCESSENTRY32);
179 typedef BOOL(WINAPI *THREAD32) (HANDLE, LPTHREADENTRY32);
180 typedef BOOL(WINAPI *MODULE32) (HANDLE, LPMODULEENTRY32);
183 # include <lmstats.h>
185 * The NET API is Unicode only. It requires the use of the UNICODE macro.
186 * When UNICODE is defined LPTSTR becomes LPWSTR. LMSTR was was added to the
187 * Platform SDK to allow the NET API to be used in non-Unicode applications
188 * provided that Unicode strings were still used for input. LMSTR is defined
191 typedef NET_API_STATUS(NET_API_FUNCTION *NETSTATGET)
192 (LPWSTR, LPWSTR, DWORD, DWORD, LPBYTE *);
193 typedef NET_API_STATUS(NET_API_FUNCTION *NETFREE) (LPBYTE);
194 # endif /* !OPENSSL_SYS_WINCE */
199 HCRYPTPROV hProvider = 0;
203 # if defined(OPENSSL_SYS_WINCE)
204 # if defined(_WIN32_WCE) && _WIN32_WCE>=300
206 * Even though MSDN says _WIN32_WCE>=210, it doesn't seem to be available
207 * in commonly available implementations prior 300...
211 /* poll the CryptoAPI PRNG */
212 /* The CryptoAPI returns sizeof(buf) bytes of randomness */
213 if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
214 CRYPT_VERIFYCONTEXT)) {
215 if (CryptGenRandom(hProvider, sizeof(buf), buf))
216 RAND_add(buf, sizeof(buf), sizeof(buf));
217 CryptReleaseContext(hProvider, 0);
221 # else /* OPENSSL_SYS_WINCE */
223 * None of below libraries are present on Windows CE, which is
224 * why we #ifndef the whole section. This also excuses us from
225 * handling the GetProcAddress issue. The trouble is that in
226 * real Win32 API GetProcAddress is available in ANSI flavor
227 * only. In WinCE on the other hand GetProcAddress is a macro
228 * most commonly defined as GetProcAddressW, which accepts
229 * Unicode argument. If we were to call GetProcAddress under
230 * WinCE, I'd recommend to either redefine GetProcAddress as
231 * GetProcAddressA (there seem to be one in common CE spec) or
232 * implement own shim routine, which would accept ANSI argument
233 * and expand it to Unicode.
236 /* load functions dynamically - not available on all systems */
237 HMODULE advapi = LoadLibrary(TEXT("ADVAPI32.DLL"));
238 HMODULE kernel = LoadLibrary(TEXT("KERNEL32.DLL"));
240 HMODULE netapi = LoadLibrary(TEXT("NETAPI32.DLL"));
241 CRYPTACQUIRECONTEXTW acquire = NULL;
242 CRYPTGENRANDOM gen = NULL;
243 CRYPTRELEASECONTEXT release = NULL;
244 NETSTATGET netstatget = NULL;
245 NETFREE netfree = NULL;
250 (NETSTATGET) GetProcAddress(netapi, "NetStatisticsGet");
251 netfree = (NETFREE) GetProcAddress(netapi, "NetApiBufferFree");
254 if (netstatget && netfree) {
257 * NetStatisticsGet() is a Unicode only function
258 * STAT_WORKSTATION_0 contains 45 fields and STAT_SERVER_0
259 * contains 17 fields. We treat each field as a source of one
263 if (netstatget(NULL, L"LanmanWorkstation", 0, 0, &outbuf) == 0) {
264 RAND_add(outbuf, sizeof(STAT_WORKSTATION_0), 45);
267 if (netstatget(NULL, L"LanmanServer", 0, 0, &outbuf) == 0) {
268 RAND_add(outbuf, sizeof(STAT_SERVER_0), 17);
277 * It appears like this can cause an exception deep within
278 * ADVAPI32.DLL at random times on Windows 2000. Reported by Jeffrey
279 * Altman. Only use it on NT.
284 * If it's available, then it's available in both ANSI
285 * and UNICODE flavors even in Win9x, documentation says.
286 * We favor Unicode...
288 acquire = (CRYPTACQUIRECONTEXTW) GetProcAddress(advapi,
289 "CryptAcquireContextW");
290 gen = (CRYPTGENRANDOM) GetProcAddress(advapi, "CryptGenRandom");
291 release = (CRYPTRELEASECONTEXT) GetProcAddress(advapi,
292 "CryptReleaseContext");
295 if (acquire && gen && release) {
296 /* poll the CryptoAPI PRNG */
297 /* The CryptoAPI returns sizeof(buf) bytes of randomness */
298 if (acquire(&hProvider, NULL, NULL, PROV_RSA_FULL,
299 CRYPT_VERIFYCONTEXT)) {
300 if (gen(hProvider, sizeof(buf), buf) != 0) {
301 RAND_add(buf, sizeof(buf), 0);
304 release(hProvider, 0);
307 /* poll the Pentium PRG with CryptoAPI */
308 if (acquire(&hProvider, 0, INTEL_DEF_PROV, PROV_INTEL_SEC, 0)) {
309 if (gen(hProvider, sizeof(buf), buf) != 0) {
310 RAND_add(buf, sizeof(buf), sizeof(buf));
313 release(hProvider, 0);
320 if ((!check_winnt() ||
321 !OPENSSL_isservice()) &&
322 (user = LoadLibrary(TEXT("USER32.DLL")))) {
323 GETCURSORINFO cursor;
324 GETFOREGROUNDWINDOW win;
325 GETQUEUESTATUS queue;
328 (GETFOREGROUNDWINDOW) GetProcAddress(user,
329 "GetForegroundWindow");
330 cursor = (GETCURSORINFO) GetProcAddress(user, "GetCursorInfo");
331 queue = (GETQUEUESTATUS) GetProcAddress(user, "GetQueueStatus");
336 RAND_add(&h, sizeof(h), 0);
340 * unfortunately, its not safe to call GetCursorInfo() on NT4
341 * even though it exists in SP3 (or SP6) and higher.
343 if (check_winnt() && !check_win_minplat(5))
347 /* cursor position */
348 /* assume 2 bytes of entropy */
350 ci.cbSize = sizeof(CURSORINFO);
352 RAND_add(&ci, ci.cbSize, 2);
356 /* message queue status */
357 /* assume 1 byte of entropy */
358 w = queue(QS_ALLEVENTS);
359 RAND_add(&w, sizeof(w), 1);
366 * Toolhelp32 snapshot: enumerate processes, threads, modules and heap
367 * http://msdn.microsoft.com/library/psdk/winbase/toolhelp_5pfd.htm
368 * (Win 9x and 2000 only, not available on NT)
370 * This seeding method was proposed in Peter Gutmann, Software
371 * Generation of Practically Strong Random Numbers,
372 * http://www.usenix.org/publications/library/proceedings/sec98/gutmann.html
373 * revised version at http://www.cryptoengines.com/~peter/06_random.pdf
374 * (The assignment of entropy estimates below is arbitrary, but based
375 * on Peter's analysis the full poll appears to be safe. Additional
376 * interactive seeding is encouraged.)
380 CREATETOOLHELP32SNAPSHOT snap;
381 CLOSETOOLHELP32SNAPSHOT close_snap;
384 HEAP32FIRST heap_first;
385 HEAP32NEXT heap_next;
386 HEAP32LIST heaplist_first, heaplist_next;
387 PROCESS32 process_first, process_next;
388 THREAD32 thread_first, thread_next;
389 MODULE32 module_first, module_next;
398 snap = (CREATETOOLHELP32SNAPSHOT)
399 GetProcAddress(kernel, "CreateToolhelp32Snapshot");
400 close_snap = (CLOSETOOLHELP32SNAPSHOT)
401 GetProcAddress(kernel, "CloseToolhelp32Snapshot");
402 heap_first = (HEAP32FIRST) GetProcAddress(kernel, "Heap32First");
403 heap_next = (HEAP32NEXT) GetProcAddress(kernel, "Heap32Next");
405 (HEAP32LIST) GetProcAddress(kernel, "Heap32ListFirst");
407 (HEAP32LIST) GetProcAddress(kernel, "Heap32ListNext");
409 (PROCESS32) GetProcAddress(kernel, "Process32First");
411 (PROCESS32) GetProcAddress(kernel, "Process32Next");
412 thread_first = (THREAD32) GetProcAddress(kernel, "Thread32First");
413 thread_next = (THREAD32) GetProcAddress(kernel, "Thread32Next");
414 module_first = (MODULE32) GetProcAddress(kernel, "Module32First");
415 module_next = (MODULE32) GetProcAddress(kernel, "Module32Next");
417 if (snap && heap_first && heap_next && heaplist_first &&
418 heaplist_next && process_first && process_next &&
419 thread_first && thread_next && module_first &&
420 module_next && (handle = snap(TH32CS_SNAPALL, 0))
421 != INVALID_HANDLE_VALUE) {
422 /* heap list and heap walking */
424 * HEAPLIST32 contains 3 fields that will change with each
425 * entry. Consider each field a source of 1 byte of entropy.
426 * HEAPENTRY32 contains 5 fields that will change with each
427 * entry. Consider each field a source of 1 byte of entropy.
429 ZeroMemory(&hlist, sizeof(HEAPLIST32));
430 hlist.dwSize = sizeof(HEAPLIST32);
432 starttime = GetTickCount();
434 if (heaplist_first(handle, &hlist)) {
436 * following discussion on dev ML, exception on WinCE (or
437 * other Win platform) is theoretically of unknown
438 * origin; prevent infinite loop here when this
439 * theoretical case occurs; otherwise cope with the
440 * expected (MSDN documented) exception-throwing
441 * behaviour of Heap32Next() on WinCE.
443 * based on patch in original message by Tanguy Fautré
444 * (2009/03/02) Subject: RAND_poll() and
445 * CreateToolhelp32Snapshot() stability
447 int ex_cnt_limit = 42;
449 RAND_add(&hlist, hlist.dwSize, 3);
451 ZeroMemory(&hentry, sizeof(HEAPENTRY32));
452 hentry.dwSize = sizeof(HEAPENTRY32);
453 if (heap_first(&hentry,
458 RAND_add(&hentry, hentry.dwSize, 5);
459 while (heap_next(&hentry)
461 || (GetTickCount() - starttime) <
466 __except(EXCEPTION_EXECUTE_HANDLER) {
468 * ignore access violations when walking the heap
473 } while (heaplist_next(handle, &hlist)
475 || (GetTickCount() - starttime) < MAXDELAY)
476 && ex_cnt_limit > 0);
479 if (heaplist_first(handle, &hlist)) {
481 RAND_add(&hlist, hlist.dwSize, 3);
482 hentry.dwSize = sizeof(HEAPENTRY32);
483 if (heap_first(&hentry,
488 RAND_add(&hentry, hentry.dwSize, 5);
489 while (heap_next(&hentry)
492 } while (heaplist_next(handle, &hlist)
494 || (GetTickCount() - starttime) < MAXDELAY));
498 /* process walking */
500 * PROCESSENTRY32 contains 9 fields that will change with
501 * each entry. Consider each field a source of 1 byte of
504 p.dwSize = sizeof(PROCESSENTRY32);
507 starttime = GetTickCount();
508 if (process_first(handle, &p))
510 RAND_add(&p, p.dwSize, 9);
511 while (process_next(handle, &p)
513 || (GetTickCount() - starttime) < MAXDELAY));
517 * THREADENTRY32 contains 6 fields that will change with each
518 * entry. Consider each field a source of 1 byte of entropy.
520 t.dwSize = sizeof(THREADENTRY32);
522 starttime = GetTickCount();
523 if (thread_first(handle, &t))
525 RAND_add(&t, t.dwSize, 6);
526 while (thread_next(handle, &t)
528 || (GetTickCount() - starttime) < MAXDELAY));
532 * MODULEENTRY32 contains 9 fields that will change with each
533 * entry. Consider each field a source of 1 byte of entropy.
535 m.dwSize = sizeof(MODULEENTRY32);
537 starttime = GetTickCount();
538 if (module_first(handle, &m))
540 RAND_add(&m, m.dwSize, 9);
541 while (module_next(handle, &m)
543 || (GetTickCount() - starttime) < MAXDELAY));
554 # endif /* !OPENSSL_SYS_WINCE */
559 /* memory usage statistics */
560 GlobalMemoryStatus(&mst);
561 RAND_add(&mst, sizeof(mst), 1);
564 w = GetCurrentProcessId();
565 RAND_add(&w, sizeof(w), 1);
570 int RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam)
572 double add_entropy = 0;
585 static int lastx, lasty, lastdx, lastdy;
592 if (dx != 0 && dy != 0 && dx - lastdx != 0 && dy - lastdy != 0)
594 lastx = x, lasty = y;
595 lastdx = dx, lastdy = dy;
601 RAND_add(&iMsg, sizeof(iMsg), add_entropy);
602 RAND_add(&wParam, sizeof(wParam), 0);
603 RAND_add(&lParam, sizeof(lParam), 0);
605 return (RAND_status());
608 void RAND_screen(void)
609 { /* function available for backward
615 /* feed timing information to the PRNG */
616 static void readtimer(void)
620 static int have_perfc = 1;
621 # if defined(_MSC_VER) && defined(_M_X86)
622 static int have_tsc = 1;
628 _emit 0x0f _emit 0x31 mov cyclecount, eax}
629 RAND_add(&cyclecount, sizeof(cyclecount), 1);
631 __except(EXCEPTION_EXECUTE_HANDLER) {
640 if (QueryPerformanceCounter(&l) == 0)
643 RAND_add(&l, sizeof(l), 0);
646 if (!have_tsc && !have_perfc) {
648 RAND_add(&w, sizeof(w), 0);
652 /* feed screen contents to PRNG */
653 /*****************************************************************************
655 * Created 960901 by Gertjan van Oosten, gertjan@West.NL, West Consulting B.V.
658 * <URL:http://support.microsoft.com/default.aspx?scid=kb;[LN];97193>;
659 * the original copyright message is:
661 * (C) Copyright Microsoft Corp. 1993. All rights reserved.
663 * You have a royalty-free right to use, modify, reproduce and
664 * distribute the Sample Files (and/or any modified version) in
665 * any way you find useful, provided that you agree that
666 * Microsoft has no warranty obligations or liability for any
667 * Sample Application Files which are modified.
670 static void readscreen(void)
672 # if !defined(OPENSSL_SYS_WINCE) && !defined(OPENSSL_SYS_WIN32_CYGWIN)
673 HDC hScrDC; /* screen DC */
674 HBITMAP hBitmap; /* handle for our bitmap */
675 BITMAP bm; /* bitmap properties */
676 unsigned int size; /* size of bitmap */
677 char *bmbits; /* contents of bitmap */
678 int w; /* screen width */
679 int h; /* screen height */
680 int y; /* y-coordinate of screen lines to grab */
681 int n = 16; /* number of screen lines to grab at a time */
682 BITMAPINFOHEADER bi; /* info about the bitmap */
684 if (check_winnt() && OPENSSL_isservice() > 0)
687 /* Get a reference to the screen DC */
688 hScrDC = GetDC(NULL);
690 /* Get screen resolution */
691 w = GetDeviceCaps(hScrDC, HORZRES);
692 h = GetDeviceCaps(hScrDC, VERTRES);
694 /* Create a bitmap compatible with the screen DC */
695 hBitmap = CreateCompatibleBitmap(hScrDC, w, n);
697 /* Get bitmap properties */
698 GetObject(hBitmap, sizeof(BITMAP), (LPSTR) & bm);
699 size = (unsigned int)bm.bmWidthBytes * bm.bmHeight * bm.bmPlanes;
701 bi.biSize = sizeof(BITMAPINFOHEADER);
702 bi.biWidth = bm.bmWidth;
703 bi.biHeight = bm.bmHeight;
704 bi.biPlanes = bm.bmPlanes;
705 bi.biBitCount = bm.bmBitsPixel;
706 bi.biCompression = BI_RGB;
708 bi.biXPelsPerMeter = 0;
709 bi.biYPelsPerMeter = 0;
711 bi.biClrImportant = 0;
713 bmbits = OPENSSL_malloc(size);
714 if (bmbits != NULL) {
715 /* Now go through the whole screen, repeatedly grabbing n lines */
716 for (y = 0; y < h - n; y += n) {
717 unsigned char md[MD_DIGEST_LENGTH];
719 /* Copy the bits of the current line range into the buffer */
720 GetDIBits(hScrDC, hBitmap, y, n,
721 bmbits, (BITMAPINFO *) & bi, DIB_RGB_COLORS);
723 /* Get the hash of the bitmap */
724 MD(bmbits, size, md);
726 /* Seed the random generator with the hash value */
727 RAND_add(md, MD_DIGEST_LENGTH, 0);
730 OPENSSL_free(bmbits);
734 DeleteObject(hBitmap);
735 ReleaseDC(NULL, hScrDC);
736 # endif /* !OPENSSL_SYS_WINCE */