/* 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.] */ #define ENTROPY_NEEDED 32 /* require 128 bits of randomness */ #ifndef MD_RAND_DEBUG # ifndef NDEBUG # define NDEBUG # endif #endif #include #include #include #include #include "openssl/e_os.h" #include #include #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 for his comments */ #if defined(USE_MD5_RAND) #include #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 #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 #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 #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 /* #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 unsigned entropy=0; 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, int add_entropy); static int ssleay_rand_bytes(unsigned char *buf, int num); static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num); RAND_METHOD rand_ssleay_meth={ ssleay_rand_seed, ssleay_rand_bytes, ssleay_rand_cleanup, ssleay_rand_add, ssleay_rand_pseudo_bytes, }; 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, int 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 16 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 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= 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]; } CRYPTO_w_unlock(CRYPTO_LOCK_RAND); #ifndef THREADS assert(md_c[1] == md_count[1]); #endif if (entropy < ENTROPY_NEEDED) entropy += add; } static void ssleay_rand_seed(const void *buf, int num) { ssleay_rand_add(buf, num, num); } 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; static int init=1; unsigned long l; #ifndef GETPID_IS_MEANINGLESS pid_t curr_pid = getpid(); #endif #ifdef DEVRANDOM FILE *fh; #endif #ifdef PREDICT { static unsigned char val=0; for (i=0; i= ENTROPY_NEEDED); 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= 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); } #ifdef WINDOWS #include #include /***************************************************************************** * 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 * ; * 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 origional 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 approximatly 49,000 56 byte MD5 * digests or digesting 2.7 mbytes. What I have put in place would * be 48 16k MD5 digests, or efectivly 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