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- /* crypto/rand/md_rand.c */
- /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
- * All rights reserved.
- *
- * This package is an SSL implementation written
- * by Eric Young (eay@cryptsoft.com).
- * The implementation was written so as to conform with Netscapes SSL.
- *
- * This library is free for commercial and non-commercial use as long as
- * the following conditions are aheared to. The following conditions
- * apply to all code found in this distribution, be it the RC4, RSA,
- * lhash, DES, etc., code; not just the SSL code. The SSL documentation
- * included with this distribution is covered by the same copyright terms
- * except that the holder is Tim Hudson (tjh@cryptsoft.com).
- *
- * Copyright remains Eric Young's, and as such any Copyright notices in
- * the code are not to be removed.
- * If this package is used in a product, Eric Young should be given attribution
- * as the author of the parts of the library used.
- * This can be in the form of a textual message at program startup or
- * in documentation (online or textual) provided with the package.
- *
- * 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 copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * "This product includes cryptographic software written by
- * Eric Young (eay@cryptsoft.com)"
- * The word 'cryptographic' can be left out if the rouines from the library
- * being used are not cryptographic related :-).
- * 4. If you include any Windows specific code (or a derivative thereof) from
- * the apps directory (application code) you must include an acknowledgement:
- * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
- *
- * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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.
- *
- * The licence and distribution terms for any publically available version or
- * derivative of this code cannot be changed. i.e. this code cannot simply be
- * copied and put under another distribution licence
- * [including the GNU Public Licence.]
- */
- /* ====================================================================
- * Copyright (c) 1998-2000 The OpenSSL Project. 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.
- *
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- *
- * 3. All advertising materials mentioning features or use of this
- * software must display the following acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
- *
- * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
- * endorse or promote products derived from this software without
- * prior written permission. For written permission, please contact
- * openssl-core@openssl.org.
- *
- * 5. Products derived from this software may not be called "OpenSSL"
- * nor may "OpenSSL" appear in their names without prior written
- * permission of the OpenSSL Project.
- *
- * 6. Redistributions of any form whatsoever must retain the following
- * acknowledgment:
- * "This product includes software developed by the OpenSSL Project
- * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
- *
- * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
- * EXPRESSED 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 OpenSSL PROJECT OR
- * ITS 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.
- * ====================================================================
- *
- * This product includes cryptographic software written by Eric Young
- * (eay@cryptsoft.com). This product includes software written by Tim
- * Hudson (tjh@cryptsoft.com).
- *
- */
- #define ENTROPY_NEEDED 16 /* require 128 bits = 16 bytes of randomness */
- #ifndef MD_RAND_DEBUG
- # ifndef NDEBUG
- # define NDEBUG
- # endif
- #endif
- #include <assert.h>
- #include <stdio.h>
- #include <time.h>
- #include <string.h>
- #include "openssl/e_os.h"
- #include <openssl/crypto.h>
- #include <openssl/err.h>
- #if !defined(USE_MD5_RAND) && !defined(USE_SHA1_RAND) && !defined(USE_MDC2_RAND) && !defined(USE_MD2_RAND)
- #if !defined(NO_SHA) && !defined(NO_SHA1)
- #define USE_SHA1_RAND
- #elif !defined(NO_MD5)
- #define USE_MD5_RAND
- #elif !defined(NO_MDC2) && !defined(NO_DES)
- #define USE_MDC2_RAND
- #elif !defined(NO_MD2)
- #define USE_MD2_RAND
- #else
- #error No message digest algorithm available
- #endif
- #endif
- /* Changed how the state buffer used. I now attempt to 'wrap' such
- * that I don't run over the same locations the next time go through
- * the 1023 bytes - many thanks to
- * Robert J. LeBlanc <rjl@renaissoft.com> for his comments
- */
- #if defined(USE_MD5_RAND)
- #include <openssl/md5.h>
- #define MD_DIGEST_LENGTH MD5_DIGEST_LENGTH
- #define MD_CTX MD5_CTX
- #define MD_Init(a) MD5_Init(a)
- #define MD_Update(a,b,c) MD5_Update(a,b,c)
- #define MD_Final(a,b) MD5_Final(a,b)
- #define MD(a,b,c) MD5(a,b,c)
- #elif defined(USE_SHA1_RAND)
- #include <openssl/sha.h>
- #define MD_DIGEST_LENGTH SHA_DIGEST_LENGTH
- #define MD_CTX SHA_CTX
- #define MD_Init(a) SHA1_Init(a)
- #define MD_Update(a,b,c) SHA1_Update(a,b,c)
- #define MD_Final(a,b) SHA1_Final(a,b)
- #define MD(a,b,c) SHA1(a,b,c)
- #elif defined(USE_MDC2_RAND)
- #include <openssl/mdc2.h>
- #define MD_DIGEST_LENGTH MDC2_DIGEST_LENGTH
- #define MD_CTX MDC2_CTX
- #define MD_Init(a) MDC2_Init(a)
- #define MD_Update(a,b,c) MDC2_Update(a,b,c)
- #define MD_Final(a,b) MDC2_Final(a,b)
- #define MD(a,b,c) MDC2(a,b,c)
- #elif defined(USE_MD2_RAND)
- #include <openssl/md2.h>
- #define MD_DIGEST_LENGTH MD2_DIGEST_LENGTH
- #define MD_CTX MD2_CTX
- #define MD_Init(a) MD2_Init(a)
- #define MD_Update(a,b,c) MD2_Update(a,b,c)
- #define MD_Final(a,b) MD2_Final(a,b)
- #define MD(a,b,c) MD2(a,b,c)
- #endif
- #include <openssl/rand.h>
- #ifdef BN_DEBUG
- # define PREDICT
- #endif
- /* #define NORAND 1 */
- /* #define PREDICT 1 */
- #define STATE_SIZE 1023
- static int state_num=0,state_index=0;
- static unsigned char state[STATE_SIZE+MD_DIGEST_LENGTH];
- static unsigned char md[MD_DIGEST_LENGTH];
- static long md_count[2]={0,0};
- static double entropy=0;
- static int initialized=0;
- #ifdef PREDICT
- int rand_predictable=0;
- #endif
- const char *RAND_version="RAND" OPENSSL_VERSION_PTEXT;
- static void ssleay_rand_cleanup(void);
- static void ssleay_rand_seed(const void *buf, int num);
- static void ssleay_rand_add(const void *buf, int num, double add_entropy);
- static int ssleay_rand_bytes(unsigned char *buf, int num);
- static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num);
- static int ssleay_rand_status(void);
- RAND_METHOD rand_ssleay_meth={
- ssleay_rand_seed,
- ssleay_rand_bytes,
- ssleay_rand_cleanup,
- ssleay_rand_add,
- ssleay_rand_pseudo_bytes,
- ssleay_rand_status
- };
- RAND_METHOD *RAND_SSLeay(void)
- {
- return(&rand_ssleay_meth);
- }
- static void ssleay_rand_cleanup(void)
- {
- memset(state,0,sizeof(state));
- state_num=0;
- state_index=0;
- memset(md,0,MD_DIGEST_LENGTH);
- md_count[0]=0;
- md_count[1]=0;
- entropy=0;
- }
- static void ssleay_rand_add(const void *buf, int num, double add)
- {
- int i,j,k,st_idx;
- long md_c[2];
- unsigned char local_md[MD_DIGEST_LENGTH];
- MD_CTX m;
- #ifdef NORAND
- return;
- #endif
- /*
- * (Based on the rand(3) manpage)
- *
- * The input is chopped up into units of 20 bytes (or less for
- * the last block). Each of these blocks is run through the hash
- * function as follows: The data passed to the hash function
- * is the current 'md', the same number of bytes from the 'state'
- * (the location determined by in incremented looping index) as
- * the current 'block', the new key data 'block', and 'count'
- * (which is incremented after each use).
- * The result of this is kept in 'md' and also xored into the
- * 'state' at the same locations that were used as input into the
- * hash function.
- */
- CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- st_idx=state_index;
- /* use our own copies of the counters so that even
- * if a concurrent thread seeds with exactly the
- * same data and uses the same subarray there's _some_
- * difference */
- md_c[0] = md_count[0];
- md_c[1] = md_count[1];
- memcpy(local_md, md, sizeof md);
- /* state_index <= state_num <= STATE_SIZE */
- state_index += num;
- if (state_index >= STATE_SIZE)
- {
- state_index%=STATE_SIZE;
- state_num=STATE_SIZE;
- }
- else if (state_num < STATE_SIZE)
- {
- if (state_index > state_num)
- state_num=state_index;
- }
- /* state_index <= state_num <= STATE_SIZE */
- /* state[st_idx], ..., state[(st_idx + num - 1) % STATE_SIZE]
- * are what we will use now, but other threads may use them
- * as well */
- md_count[1] += (num / MD_DIGEST_LENGTH) + (num % MD_DIGEST_LENGTH > 0);
- CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
- for (i=0; i<num; i+=MD_DIGEST_LENGTH)
- {
- j=(num-i);
- j=(j > MD_DIGEST_LENGTH)?MD_DIGEST_LENGTH:j;
- MD_Init(&m);
- MD_Update(&m,local_md,MD_DIGEST_LENGTH);
- k=(st_idx+j)-STATE_SIZE;
- if (k > 0)
- {
- MD_Update(&m,&(state[st_idx]),j-k);
- MD_Update(&m,&(state[0]),k);
- }
- else
- MD_Update(&m,&(state[st_idx]),j);
-
- MD_Update(&m,buf,j);
- MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
- MD_Final(local_md,&m);
- md_c[1]++;
- buf=(const char *)buf + j;
- for (k=0; k<j; k++)
- {
- /* Parallel threads may interfere with this,
- * but always each byte of the new state is
- * the XOR of some previous value of its
- * and local_md (itermediate values may be lost).
- * Alway using locking could hurt performance more
- * than necessary given that conflicts occur only
- * when the total seeding is longer than the random
- * state. */
- state[st_idx++]^=local_md[k];
- if (st_idx >= STATE_SIZE)
- st_idx=0;
- }
- }
- memset((char *)&m,0,sizeof(m));
- CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- /* Don't just copy back local_md into md -- this could mean that
- * other thread's seeding remains without effect (except for
- * the incremented counter). By XORing it we keep at least as
- * much entropy as fits into md. */
- for (k = 0; k < sizeof md; k++)
- {
- md[k] ^= local_md[k];
- }
- if (entropy < ENTROPY_NEEDED) /* stop counting when we have enough */
- entropy += add;
- CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
-
- #ifndef THREADS
- assert(md_c[1] == md_count[1]);
- #endif
- }
- static void ssleay_rand_seed(const void *buf, int num)
- {
- ssleay_rand_add(buf, num, num);
- }
- static void ssleay_rand_initialize(void)
- {
- unsigned long l;
- #ifndef GETPID_IS_MEANINGLESS
- pid_t curr_pid = getpid();
- #endif
- #ifdef DEVRANDOM
- FILE *fh;
- #endif
- #ifdef NORAND
- return;
- #endif
- CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
- /* put in some default random data, we need more than just this */
- #ifndef GETPID_IS_MEANINGLESS
- l=curr_pid;
- RAND_add(&l,sizeof(l),0);
- l=getuid();
- RAND_add(&l,sizeof(l),0);
- #endif
- l=time(NULL);
- RAND_add(&l,sizeof(l),0);
- #ifdef DEVRANDOM
- /* Use a random entropy pool device. Linux, FreeBSD and OpenBSD
- * have this. Use /dev/urandom if you can as /dev/random may block
- * if it runs out of random entries. */
- if ((fh = fopen(DEVRANDOM, "r")) != NULL)
- {
- unsigned char tmpbuf[ENTROPY_NEEDED];
- int n;
-
- setvbuf(fh, NULL, _IONBF, 0);
- n=fread((unsigned char *)tmpbuf,1,ENTROPY_NEEDED,fh);
- fclose(fh);
- RAND_add(tmpbuf,sizeof tmpbuf,n);
- memset(tmpbuf,0,n);
- }
- #endif
- #ifdef PURIFY
- memset(state,0,STATE_SIZE);
- memset(md,0,MD_DIGEST_LENGTH);
- #endif
- CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- initialized=1;
- }
- static int ssleay_rand_bytes(unsigned char *buf, int num)
- {
- int i,j,k,st_num,st_idx;
- int ok;
- long md_c[2];
- unsigned char local_md[MD_DIGEST_LENGTH];
- MD_CTX m;
- #ifndef GETPID_IS_MEANINGLESS
- pid_t curr_pid = getpid();
- #endif
- #ifdef PREDICT
- if (rand_predictable)
- {
- static unsigned char val=0;
- for (i=0; i<num; i++)
- buf[i]=val++;
- return(1);
- }
- #endif
- /*
- * (Based on the rand(3) manpage:)
- *
- * For each group of 10 bytes (or less), we do the following:
- *
- * Input into the hash function the top 10 bytes from the
- * local 'md' (which is initialized from the global 'md'
- * before any bytes are generated), the bytes that are
- * to be overwritten by the random bytes, and bytes from the
- * 'state' (incrementing looping index). From this digest output
- * (which is kept in 'md'), the top (up to) 10 bytes are
- * returned to the caller and the bottom (up to) 10 bytes are xored
- * into the 'state'.
- * Finally, after we have finished 'num' random bytes for the
- * caller, 'count' (which is incremented) and the local and global 'md'
- * are fed into the hash function and the results are kept in the
- * global 'md'.
- */
- CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- if (!initialized)
- ssleay_rand_initialize();
- ok = (entropy >= ENTROPY_NEEDED);
- if (!ok)
- {
- /* If the PRNG state is not yet unpredictable, then seeing
- * the PRNG output may help attackers to determine the new
- * state; thus we have to decrease the entropy estimate.
- * Once we've had enough initial seeding we don't bother to
- * adjust the entropy count, though, because we're not ambitious
- * to provide *information-theoretic* randomness.
- */
- entropy -= num;
- if (entropy < 0)
- entropy = 0;
- }
- st_idx=state_index;
- st_num=state_num;
- md_c[0] = md_count[0];
- md_c[1] = md_count[1];
- memcpy(local_md, md, sizeof md);
- state_index+=num;
- if (state_index > state_num)
- state_index %= state_num;
- /* state[st_idx], ..., state[(st_idx + num - 1) % st_num]
- * are now ours (but other threads may use them too) */
- md_count[0] += 1;
- CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
- while (num > 0)
- {
- j=(num >= MD_DIGEST_LENGTH/2)?MD_DIGEST_LENGTH/2:num;
- num-=j;
- MD_Init(&m);
- #ifndef GETPID_IS_MEANINGLESS
- if (curr_pid) /* just in the first iteration to save time */
- {
- MD_Update(&m,(unsigned char*)&curr_pid,sizeof curr_pid);
- curr_pid = 0;
- }
- #endif
- MD_Update(&m,&(local_md[MD_DIGEST_LENGTH/2]),MD_DIGEST_LENGTH/2);
- MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
- #ifndef PURIFY
- MD_Update(&m,buf,j); /* purify complains */
- #endif
- k=(st_idx+j)-st_num;
- if (k > 0)
- {
- MD_Update(&m,&(state[st_idx]),j-k);
- MD_Update(&m,&(state[0]),k);
- }
- else
- MD_Update(&m,&(state[st_idx]),j);
- MD_Final(local_md,&m);
- for (i=0; i<j; i++)
- {
- state[st_idx++]^=local_md[i]; /* may compete with other threads */
- *(buf++)=local_md[i+MD_DIGEST_LENGTH/2];
- if (st_idx >= st_num)
- st_idx=0;
- }
- }
- MD_Init(&m);
- MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
- MD_Update(&m,local_md,MD_DIGEST_LENGTH);
- CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- MD_Update(&m,md,MD_DIGEST_LENGTH);
- MD_Final(md,&m);
- CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
- memset(&m,0,sizeof(m));
- if (ok)
- return(1);
- else
- {
- RANDerr(RAND_F_SSLEAY_RAND_BYTES,RAND_R_PRNG_NOT_SEEDED);
- return(0);
- }
- }
- /* pseudo-random bytes that are guaranteed to be unique but not
- unpredictable */
- static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num)
- {
- int ret, err;
- ret = RAND_bytes(buf, num);
- if (ret == 0)
- {
- err = ERR_peek_error();
- if (ERR_GET_LIB(err) == ERR_LIB_RAND &&
- ERR_GET_REASON(err) == RAND_R_PRNG_NOT_SEEDED)
- (void)ERR_get_error();
- }
- return (ret);
- }
- static int ssleay_rand_status(void)
- {
- if (!initialized)
- ssleay_rand_initialize();
- return (entropy >= ENTROPY_NEEDED);
- }
- #ifdef WINDOWS
- #include <windows.h>
- #include <openssl/rand.h>
- /*****************************************************************************
- * Initialisation function for the SSL random generator. Takes the contents
- * of the screen as random seed.
- *
- * Created 960901 by Gertjan van Oosten, gertjan@West.NL, West Consulting B.V.
- *
- * Code adapted from
- * <URL:http://www.microsoft.com/kb/developr/win_dk/q97193.htm>;
- * the original copyright message is:
- *
- * (C) Copyright Microsoft Corp. 1993. All rights reserved.
- *
- * You have a royalty-free right to use, modify, reproduce and
- * distribute the Sample Files (and/or any modified version) in
- * any way you find useful, provided that you agree that
- * Microsoft has no warranty obligations or liability for any
- * Sample Application Files which are modified.
- */
- /*
- * I have modified the loading of bytes via RAND_seed() mechanism since
- * the original would have been very very CPU intensive since RAND_seed()
- * does an MD5 per 16 bytes of input. The cost to digest 16 bytes is the same
- * as that to digest 56 bytes. So under the old system, a screen of
- * 1024*768*256 would have been CPU cost of approximately 49,000 56 byte MD5
- * digests or digesting 2.7 mbytes. What I have put in place would
- * be 48 16k MD5 digests, or effectively 48*16+48 MD5 bytes or 816 kbytes
- * or about 3.5 times as much.
- * - eric
- */
- void RAND_screen(void)
- {
- HDC hScrDC; /* screen DC */
- HDC hMemDC; /* memory DC */
- HBITMAP hBitmap; /* handle for our bitmap */
- HBITMAP hOldBitmap; /* handle for previous bitmap */
- BITMAP bm; /* bitmap properties */
- unsigned int size; /* size of bitmap */
- char *bmbits; /* contents of bitmap */
- int w; /* screen width */
- int h; /* screen height */
- int y; /* y-coordinate of screen lines to grab */
- int n = 16; /* number of screen lines to grab at a time */
- /* Create a screen DC and a memory DC compatible to screen DC */
- hScrDC = CreateDC("DISPLAY", NULL, NULL, NULL);
- hMemDC = CreateCompatibleDC(hScrDC);
- /* Get screen resolution */
- w = GetDeviceCaps(hScrDC, HORZRES);
- h = GetDeviceCaps(hScrDC, VERTRES);
- /* Create a bitmap compatible with the screen DC */
- hBitmap = CreateCompatibleBitmap(hScrDC, w, n);
- /* Select new bitmap into memory DC */
- hOldBitmap = SelectObject(hMemDC, hBitmap);
- /* Get bitmap properties */
- GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&bm);
- size = (unsigned int)bm.bmWidthBytes * bm.bmHeight * bm.bmPlanes;
- bmbits = Malloc(size);
- if (bmbits) {
- /* Now go through the whole screen, repeatedly grabbing n lines */
- for (y = 0; y < h-n; y += n)
- {
- unsigned char md[MD_DIGEST_LENGTH];
- /* Bitblt screen DC to memory DC */
- BitBlt(hMemDC, 0, 0, w, n, hScrDC, 0, y, SRCCOPY);
- /* Copy bitmap bits from memory DC to bmbits */
- GetBitmapBits(hBitmap, size, bmbits);
- /* Get the MD5 of the bitmap */
- MD(bmbits,size,md);
- /* Seed the random generator with the MD5 digest */
- RAND_seed(md, MD_DIGEST_LENGTH);
- }
- Free(bmbits);
- }
- /* Select old bitmap back into memory DC */
- hBitmap = SelectObject(hMemDC, hOldBitmap);
- /* Clean up */
- DeleteObject(hBitmap);
- DeleteDC(hMemDC);
- DeleteDC(hScrDC);
- }
- #endif
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