1 /* crypto/rand/rand_win.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
58 /* ====================================================================
59 * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved.
61 * Redistribution and use in source and binary forms, with or without
62 * modification, are permitted provided that the following conditions
65 * 1. Redistributions of source code must retain the above copyright
66 * notice, this list of conditions and the following disclaimer.
68 * 2. Redistributions in binary form must reproduce the above copyright
69 * notice, this list of conditions and the following disclaimer in
70 * the documentation and/or other materials provided with the
73 * 3. All advertising materials mentioning features or use of this
74 * software must display the following acknowledgment:
75 * "This product includes software developed by the OpenSSL Project
76 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
78 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79 * endorse or promote products derived from this software without
80 * prior written permission. For written permission, please contact
81 * openssl-core@openssl.org.
83 * 5. Products derived from this software may not be called "OpenSSL"
84 * nor may "OpenSSL" appear in their names without prior written
85 * permission of the OpenSSL Project.
87 * 6. Redistributions of any form whatsoever must retain the following
89 * "This product includes software developed by the OpenSSL Project
90 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
92 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
96 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103 * OF THE POSSIBILITY OF SUCH DAMAGE.
104 * ====================================================================
106 * This product includes cryptographic software written by Eric Young
107 * (eay@cryptsoft.com). This product includes software written by Tim
108 * Hudson (tjh@cryptsoft.com).
112 #include "cryptlib.h"
113 #include <openssl/rand.h>
114 #include "rand_lcl.h"
116 #if defined(OPENSSL_SYS_WINDOWS) || defined(OPENSSL_SYS_WIN32)
117 # include <windows.h>
118 # ifndef _WIN32_WINNT
119 # define _WIN32_WINNT 0x0400
121 # include <wincrypt.h>
122 # include <tlhelp32.h>
125 * Limit the time spent walking through the heap, processes, threads and
126 * modules to a maximum of 1000 miliseconds each, unless CryptoGenRandom
129 # define MAXDELAY 1000
132 * Intel hardware RNG CSP -- available from
133 * http://developer.intel.com/design/security/rng/redist_license.htm
135 # define PROV_INTEL_SEC 22
136 # define INTEL_DEF_PROV L"Intel Hardware Cryptographic Service Provider"
138 static void readtimer(void);
139 static void readscreen(void);
142 * It appears like CURSORINFO, PCURSORINFO and LPCURSORINFO are only defined
143 * when WINVER is 0x0500 and up, which currently only happens on Win2000.
144 * Unfortunately, those are typedefs, so they're a little bit difficult to
145 * detect properly. On the other hand, the macro CURSOR_SHOWING is defined
146 * within the same conditional, so it can be use to detect the absence of
150 # ifndef CURSOR_SHOWING
152 * Information about the global cursor.
154 typedef struct tagCURSORINFO {
159 } CURSORINFO, *PCURSORINFO, *LPCURSORINFO;
161 # define CURSOR_SHOWING 0x00000001
162 # endif /* CURSOR_SHOWING */
164 # if !defined(OPENSSL_SYS_WINCE)
165 typedef BOOL(WINAPI *CRYPTACQUIRECONTEXTW) (HCRYPTPROV *, LPCWSTR, LPCWSTR,
167 typedef BOOL(WINAPI *CRYPTGENRANDOM) (HCRYPTPROV, DWORD, BYTE *);
168 typedef BOOL(WINAPI *CRYPTRELEASECONTEXT) (HCRYPTPROV, DWORD);
170 typedef HWND(WINAPI *GETFOREGROUNDWINDOW) (VOID);
171 typedef BOOL(WINAPI *GETCURSORINFO) (PCURSORINFO);
172 typedef DWORD(WINAPI *GETQUEUESTATUS) (UINT);
174 typedef HANDLE(WINAPI *CREATETOOLHELP32SNAPSHOT) (DWORD, DWORD);
175 typedef BOOL(WINAPI *CLOSETOOLHELP32SNAPSHOT) (HANDLE);
176 typedef BOOL(WINAPI *HEAP32FIRST) (LPHEAPENTRY32, DWORD, size_t);
177 typedef BOOL(WINAPI *HEAP32NEXT) (LPHEAPENTRY32);
178 typedef BOOL(WINAPI *HEAP32LIST) (HANDLE, LPHEAPLIST32);
179 typedef BOOL(WINAPI *PROCESS32) (HANDLE, LPPROCESSENTRY32);
180 typedef BOOL(WINAPI *THREAD32) (HANDLE, LPTHREADENTRY32);
181 typedef BOOL(WINAPI *MODULE32) (HANDLE, LPMODULEENTRY32);
184 # include <lmstats.h>
187 * The NET API is Unicode only. It requires the use of the UNICODE macro.
188 * When UNICODE is defined LPTSTR becomes LPWSTR. LMSTR was was added to the
189 * Platform SDK to allow the NET API to be used in non-Unicode applications
190 * provided that Unicode strings were still used for input. LMSTR is defined
193 typedef NET_API_STATUS(NET_API_FUNCTION *NETSTATGET)
194 (LPWSTR, LPWSTR, DWORD, DWORD, LPBYTE *);
195 typedef NET_API_STATUS(NET_API_FUNCTION *NETFREE) (LPBYTE);
197 # endif /* !OPENSSL_SYS_WINCE */
199 #define NOTTOOLONG(start) ((GetTickCount() - (start)) < MAXDELAY)
204 HCRYPTPROV hProvider = 0;
208 # if defined(OPENSSL_SYS_WINCE)
209 # if defined(_WIN32_WCE) && _WIN32_WCE>=300
211 * Even though MSDN says _WIN32_WCE>=210, it doesn't seem to be available
212 * in commonly available implementations prior 300...
216 /* poll the CryptoAPI PRNG */
217 /* The CryptoAPI returns sizeof(buf) bytes of randomness */
218 if (CryptAcquireContextW(&hProvider, NULL, NULL, PROV_RSA_FULL,
219 CRYPT_VERIFYCONTEXT)) {
220 if (CryptGenRandom(hProvider, sizeof(buf), buf))
221 RAND_add(buf, sizeof(buf), sizeof(buf));
222 CryptReleaseContext(hProvider, 0);
226 # else /* OPENSSL_SYS_WINCE */
228 * None of below libraries are present on Windows CE, which is
229 * why we #ifndef the whole section. This also excuses us from
230 * handling the GetProcAddress issue. The trouble is that in
231 * real Win32 API GetProcAddress is available in ANSI flavor
232 * only. In WinCE on the other hand GetProcAddress is a macro
233 * most commonly defined as GetProcAddressW, which accepts
234 * Unicode argument. If we were to call GetProcAddress under
235 * WinCE, I'd recommend to either redefine GetProcAddress as
236 * GetProcAddressA (there seem to be one in common CE spec) or
237 * implement own shim routine, which would accept ANSI argument
238 * and expand it to Unicode.
241 /* load functions dynamically - not available on all systems */
242 HMODULE advapi = LoadLibrary(TEXT("ADVAPI32.DLL"));
243 HMODULE kernel = LoadLibrary(TEXT("KERNEL32.DLL"));
245 HMODULE netapi = LoadLibrary(TEXT("NETAPI32.DLL"));
246 CRYPTACQUIRECONTEXTW acquire = NULL;
247 CRYPTGENRANDOM gen = NULL;
248 CRYPTRELEASECONTEXT release = NULL;
249 NETSTATGET netstatget = NULL;
250 NETFREE netfree = NULL;
255 (NETSTATGET) GetProcAddress(netapi, "NetStatisticsGet");
256 netfree = (NETFREE) GetProcAddress(netapi, "NetApiBufferFree");
259 if (netstatget && netfree) {
262 * NetStatisticsGet() is a Unicode only function
263 * STAT_WORKSTATION_0 contains 45 fields and STAT_SERVER_0
264 * contains 17 fields. We treat each field as a source of one
268 if (netstatget(NULL, L"LanmanWorkstation", 0, 0, &outbuf) == 0) {
269 RAND_add(outbuf, sizeof(STAT_WORKSTATION_0), 45);
272 if (netstatget(NULL, L"LanmanServer", 0, 0, &outbuf) == 0) {
273 RAND_add(outbuf, sizeof(STAT_SERVER_0), 17);
282 * It appears like this can cause an exception deep within
283 * ADVAPI32.DLL at random times on Windows 2000. Reported by Jeffrey
284 * Altman. Only use it on NT.
289 * If it's available, then it's available in both ANSI
290 * and UNICODE flavors even in Win9x, documentation says.
291 * We favor Unicode...
293 acquire = (CRYPTACQUIRECONTEXTW) GetProcAddress(advapi,
294 "CryptAcquireContextW");
295 gen = (CRYPTGENRANDOM) GetProcAddress(advapi, "CryptGenRandom");
296 release = (CRYPTRELEASECONTEXT) GetProcAddress(advapi,
297 "CryptReleaseContext");
300 if (acquire && gen && release) {
301 /* poll the CryptoAPI PRNG */
302 /* The CryptoAPI returns sizeof(buf) bytes of randomness */
303 if (acquire(&hProvider, NULL, NULL, PROV_RSA_FULL,
304 CRYPT_VERIFYCONTEXT)) {
305 if (gen(hProvider, sizeof(buf), buf) != 0) {
306 RAND_add(buf, sizeof(buf), 0);
309 printf("randomness from PROV_RSA_FULL\n");
312 release(hProvider, 0);
315 /* poll the Pentium PRG with CryptoAPI */
316 if (acquire(&hProvider, 0, INTEL_DEF_PROV, PROV_INTEL_SEC, 0)) {
317 if (gen(hProvider, sizeof(buf), buf) != 0) {
318 RAND_add(buf, sizeof(buf), sizeof(buf));
321 printf("randomness from PROV_INTEL_SEC\n");
324 release(hProvider, 0);
331 if ((!check_winnt() ||
332 !OPENSSL_isservice()) &&
333 (user = LoadLibrary(TEXT("USER32.DLL")))) {
334 GETCURSORINFO cursor;
335 GETFOREGROUNDWINDOW win;
336 GETQUEUESTATUS queue;
339 (GETFOREGROUNDWINDOW) GetProcAddress(user,
340 "GetForegroundWindow");
341 cursor = (GETCURSORINFO) GetProcAddress(user, "GetCursorInfo");
342 queue = (GETQUEUESTATUS) GetProcAddress(user, "GetQueueStatus");
347 RAND_add(&h, sizeof(h), 0);
351 * unfortunately, its not safe to call GetCursorInfo() on NT4
352 * even though it exists in SP3 (or SP6) and higher.
354 if (check_winnt() && !check_win_minplat(5))
358 /* cursor position */
359 /* assume 2 bytes of entropy */
361 ci.cbSize = sizeof(CURSORINFO);
363 RAND_add(&ci, ci.cbSize, 2);
367 /* message queue status */
368 /* assume 1 byte of entropy */
369 w = queue(QS_ALLEVENTS);
370 RAND_add(&w, sizeof(w), 1);
377 * Toolhelp32 snapshot: enumerate processes, threads, modules and heap
378 * http://msdn.microsoft.com/library/psdk/winbase/toolhelp_5pfd.htm
379 * (Win 9x and 2000 only, not available on NT)
381 * This seeding method was proposed in Peter Gutmann, Software
382 * Generation of Practically Strong Random Numbers,
383 * http://www.usenix.org/publications/library/proceedings/sec98/gutmann.html
384 * revised version at http://www.cryptoengines.com/~peter/06_random.pdf
385 * (The assignment of entropy estimates below is arbitrary, but based
386 * on Peter's analysis the full poll appears to be safe. Additional
387 * interactive seeding is encouraged.)
391 CREATETOOLHELP32SNAPSHOT snap;
392 CLOSETOOLHELP32SNAPSHOT close_snap;
395 HEAP32FIRST heap_first;
396 HEAP32NEXT heap_next;
397 HEAP32LIST heaplist_first, heaplist_next;
398 PROCESS32 process_first, process_next;
399 THREAD32 thread_first, thread_next;
400 MODULE32 module_first, module_next;
409 snap = (CREATETOOLHELP32SNAPSHOT)
410 GetProcAddress(kernel, "CreateToolhelp32Snapshot");
411 close_snap = (CLOSETOOLHELP32SNAPSHOT)
412 GetProcAddress(kernel, "CloseToolhelp32Snapshot");
413 heap_first = (HEAP32FIRST) GetProcAddress(kernel, "Heap32First");
414 heap_next = (HEAP32NEXT) GetProcAddress(kernel, "Heap32Next");
416 (HEAP32LIST) GetProcAddress(kernel, "Heap32ListFirst");
418 (HEAP32LIST) GetProcAddress(kernel, "Heap32ListNext");
420 (PROCESS32) GetProcAddress(kernel, "Process32First");
422 (PROCESS32) GetProcAddress(kernel, "Process32Next");
423 thread_first = (THREAD32) GetProcAddress(kernel, "Thread32First");
424 thread_next = (THREAD32) GetProcAddress(kernel, "Thread32Next");
425 module_first = (MODULE32) GetProcAddress(kernel, "Module32First");
426 module_next = (MODULE32) GetProcAddress(kernel, "Module32Next");
428 if (snap && heap_first && heap_next && heaplist_first &&
429 heaplist_next && process_first && process_next &&
430 thread_first && thread_next && module_first &&
431 module_next && (handle = snap(TH32CS_SNAPALL, 0))
432 != INVALID_HANDLE_VALUE) {
433 /* heap list and heap walking */
435 * HEAPLIST32 contains 3 fields that will change with each
436 * entry. Consider each field a source of 1 byte of entropy.
437 * HEAPENTRY32 contains 5 fields that will change with each
438 * entry. Consider each field a source of 1 byte of entropy.
440 ZeroMemory(&hlist, sizeof(HEAPLIST32));
441 hlist.dwSize = sizeof(HEAPLIST32);
443 starttime = GetTickCount();
445 if (heaplist_first(handle, &hlist)) {
447 * following discussion on dev ML, exception on WinCE (or
448 * other Win platform) is theoretically of unknown
449 * origin; prevent infinite loop here when this
450 * theoretical case occurs; otherwise cope with the
451 * expected (MSDN documented) exception-throwing
452 * behaviour of Heap32Next() on WinCE.
454 * based on patch in original message by Tanguy Fautré
455 * (2009/03/02) Subject: RAND_poll() and
456 * CreateToolhelp32Snapshot() stability
458 int ex_cnt_limit = 42;
460 RAND_add(&hlist, hlist.dwSize, 3);
462 ZeroMemory(&hentry, sizeof(HEAPENTRY32));
463 hentry.dwSize = sizeof(HEAPENTRY32);
464 if (heap_first(&hentry,
469 RAND_add(&hentry, hentry.dwSize, 5);
470 while (heap_next(&hentry)
471 && (!good || NOTTOOLONG(starttime))
475 __except(EXCEPTION_EXECUTE_HANDLER) {
477 * ignore access violations when walking the heap
482 } while (heaplist_next(handle, &hlist)
483 && (!good || NOTTOOLONG(starttime))
484 && ex_cnt_limit > 0);
487 if (heaplist_first(handle, &hlist)) {
489 RAND_add(&hlist, hlist.dwSize, 3);
490 hentry.dwSize = sizeof(HEAPENTRY32);
491 if (heap_first(&hentry,
496 RAND_add(&hentry, hentry.dwSize, 5);
497 while (heap_next(&hentry)
498 && (!good || NOTTOOLONG(starttime))
501 } while (heaplist_next(handle, &hlist)
502 && (!good || NOTTOOLONG(starttime)));
506 /* process walking */
508 * PROCESSENTRY32 contains 9 fields that will change with
509 * each entry. Consider each field a source of 1 byte of
512 p.dwSize = sizeof(PROCESSENTRY32);
515 starttime = GetTickCount();
516 if (process_first(handle, &p))
518 RAND_add(&p, p.dwSize, 9);
519 while (process_next(handle, &p)
520 && (!good || NOTTOOLONG(starttime)));
524 * THREADENTRY32 contains 6 fields that will change with each
525 * entry. Consider each field a source of 1 byte of entropy.
527 t.dwSize = sizeof(THREADENTRY32);
529 starttime = GetTickCount();
530 if (thread_first(handle, &t))
532 RAND_add(&t, t.dwSize, 6);
533 while (thread_next(handle, &t)
534 && (!good || NOTTOOLONG(starttime)));
538 * MODULEENTRY32 contains 9 fields that will change with each
539 * entry. Consider each field a source of 1 byte of entropy.
541 m.dwSize = sizeof(MODULEENTRY32);
543 starttime = GetTickCount();
544 if (module_first(handle, &m))
546 RAND_add(&m, m.dwSize, 9);
547 while (module_next(handle, &m)
548 && (!good || NOTTOOLONG(starttime)));
559 # endif /* !OPENSSL_SYS_WINCE */
564 /* memory usage statistics */
565 GlobalMemoryStatus(&m);
566 RAND_add(&m, sizeof(m), 1);
569 w = GetCurrentProcessId();
570 RAND_add(&w, sizeof(w), 1);
573 printf("Exiting RAND_poll\n");
579 int RAND_event(UINT iMsg, WPARAM wParam, LPARAM lParam)
581 double add_entropy = 0;
594 static int lastx, lasty, lastdx, lastdy;
601 if (dx != 0 && dy != 0 && dx - lastdx != 0 && dy - lastdy != 0)
603 lastx = x, lasty = y;
604 lastdx = dx, lastdy = dy;
610 RAND_add(&iMsg, sizeof(iMsg), add_entropy);
611 RAND_add(&wParam, sizeof(wParam), 0);
612 RAND_add(&lParam, sizeof(lParam), 0);
614 return (RAND_status());
617 void RAND_screen(void)
618 { /* function available for backward
624 /* feed timing information to the PRNG */
625 static void readtimer(void)
629 static int have_perfc = 1;
630 # if defined(_MSC_VER) && defined(_M_X86)
631 static int have_tsc = 1;
637 _emit 0x0f _emit 0x31 mov cyclecount, eax}
638 RAND_add(&cyclecount, sizeof(cyclecount), 1);
640 __except(EXCEPTION_EXECUTE_HANDLER) {
649 if (QueryPerformanceCounter(&l) == 0)
652 RAND_add(&l, sizeof(l), 0);
655 if (!have_tsc && !have_perfc) {
657 RAND_add(&w, sizeof(w), 0);
661 /* feed screen contents to PRNG */
662 /*****************************************************************************
664 * Created 960901 by Gertjan van Oosten, gertjan@West.NL, West Consulting B.V.
667 * <URL:http://support.microsoft.com/default.aspx?scid=kb;[LN];97193>;
668 * the original copyright message is:
670 * (C) Copyright Microsoft Corp. 1993. All rights reserved.
672 * You have a royalty-free right to use, modify, reproduce and
673 * distribute the Sample Files (and/or any modified version) in
674 * any way you find useful, provided that you agree that
675 * Microsoft has no warranty obligations or liability for any
676 * Sample Application Files which are modified.
679 static void readscreen(void)
681 # if !defined(OPENSSL_SYS_WINCE) && !defined(OPENSSL_SYS_WIN32_CYGWIN)
682 HDC hScrDC; /* screen DC */
683 HBITMAP hBitmap; /* handle for our bitmap */
684 BITMAP bm; /* bitmap properties */
685 unsigned int size; /* size of bitmap */
686 char *bmbits; /* contents of bitmap */
687 int w; /* screen width */
688 int h; /* screen height */
689 int y; /* y-coordinate of screen lines to grab */
690 int n = 16; /* number of screen lines to grab at a time */
691 BITMAPINFOHEADER bi; /* info about the bitmap */
693 if (check_winnt() && OPENSSL_isservice() > 0)
696 /* Get a reference to the screen DC */
697 hScrDC = GetDC(NULL);
699 /* Get screen resolution */
700 w = GetDeviceCaps(hScrDC, HORZRES);
701 h = GetDeviceCaps(hScrDC, VERTRES);
703 /* Create a bitmap compatible with the screen DC */
704 hBitmap = CreateCompatibleBitmap(hScrDC, w, n);
706 /* Get bitmap properties */
707 GetObject(hBitmap, sizeof(BITMAP), (LPSTR) & bm);
708 size = (unsigned int)bm.bmWidthBytes * bm.bmHeight * bm.bmPlanes;
710 bi.biSize = sizeof(BITMAPINFOHEADER);
711 bi.biWidth = bm.bmWidth;
712 bi.biHeight = bm.bmHeight;
713 bi.biPlanes = bm.bmPlanes;
714 bi.biBitCount = bm.bmBitsPixel;
715 bi.biCompression = BI_RGB;
717 bi.biXPelsPerMeter = 0;
718 bi.biYPelsPerMeter = 0;
720 bi.biClrImportant = 0;
722 bmbits = OPENSSL_malloc(size);
724 /* Now go through the whole screen, repeatedly grabbing n lines */
725 for (y = 0; y < h - n; y += n) {
726 unsigned char md[MD_DIGEST_LENGTH];
728 /* Copy the bits of the current line range into the buffer */
729 GetDIBits(hScrDC, hBitmap, y, n,
730 bmbits, (BITMAPINFO *) & bi, DIB_RGB_COLORS);
732 /* Get the hash of the bitmap */
733 MD(bmbits, size, md);
735 /* Seed the random generator with the hash value */
736 RAND_add(md, MD_DIGEST_LENGTH, 0);
739 OPENSSL_free(bmbits);
743 DeleteObject(hBitmap);
744 ReleaseDC(NULL, hScrDC);
745 # endif /* !OPENSSL_SYS_WINCE */