1 /* crypto/rand/md_rand.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.]
59 #define ENTROPY_NEEDED 32 /* require 128 bits of randomness */
72 #include "openssl/e_os.h"
74 #include <openssl/crypto.h>
75 #include <openssl/err.h>
77 #if !defined(USE_MD5_RAND) && !defined(USE_SHA1_RAND) && !defined(USE_MDC2_RAND) && !defined(USE_MD2_RAND)
78 #if !defined(NO_SHA) && !defined(NO_SHA1)
80 #elif !defined(NO_MD5)
82 #elif !defined(NO_MDC2) && !defined(NO_DES)
84 #elif !defined(NO_MD2)
87 #error No message digest algorithm available
91 /* Changed how the state buffer used. I now attempt to 'wrap' such
92 * that I don't run over the same locations the next time go through
93 * the 1023 bytes - many thanks to
94 * Robert J. LeBlanc <rjl@renaissoft.com> for his comments
97 #if defined(USE_MD5_RAND)
98 #include <openssl/md5.h>
99 #define MD_DIGEST_LENGTH MD5_DIGEST_LENGTH
100 #define MD_CTX MD5_CTX
101 #define MD_Init(a) MD5_Init(a)
102 #define MD_Update(a,b,c) MD5_Update(a,b,c)
103 #define MD_Final(a,b) MD5_Final(a,b)
104 #define MD(a,b,c) MD5(a,b,c)
105 #elif defined(USE_SHA1_RAND)
106 #include <openssl/sha.h>
107 #define MD_DIGEST_LENGTH SHA_DIGEST_LENGTH
108 #define MD_CTX SHA_CTX
109 #define MD_Init(a) SHA1_Init(a)
110 #define MD_Update(a,b,c) SHA1_Update(a,b,c)
111 #define MD_Final(a,b) SHA1_Final(a,b)
112 #define MD(a,b,c) SHA1(a,b,c)
113 #elif defined(USE_MDC2_RAND)
114 #include <openssl/mdc2.h>
115 #define MD_DIGEST_LENGTH MDC2_DIGEST_LENGTH
116 #define MD_CTX MDC2_CTX
117 #define MD_Init(a) MDC2_Init(a)
118 #define MD_Update(a,b,c) MDC2_Update(a,b,c)
119 #define MD_Final(a,b) MDC2_Final(a,b)
120 #define MD(a,b,c) MDC2(a,b,c)
121 #elif defined(USE_MD2_RAND)
122 #include <openssl/md2.h>
123 #define MD_DIGEST_LENGTH MD2_DIGEST_LENGTH
124 #define MD_CTX MD2_CTX
125 #define MD_Init(a) MD2_Init(a)
126 #define MD_Update(a,b,c) MD2_Update(a,b,c)
127 #define MD_Final(a,b) MD2_Final(a,b)
128 #define MD(a,b,c) MD2(a,b,c)
131 #include <openssl/rand.h>
133 /* #define NORAND 1 */
134 /* #define PREDICT 1 */
136 #define STATE_SIZE 1023
137 static int state_num=0,state_index=0;
138 static unsigned char state[STATE_SIZE+MD_DIGEST_LENGTH];
139 static unsigned char md[MD_DIGEST_LENGTH];
140 static long md_count[2]={0,0};
141 static int entropy=0;
143 const char *RAND_version="RAND" OPENSSL_VERSION_PTEXT;
145 static void ssleay_rand_cleanup(void);
146 static void ssleay_rand_seed(const void *buf, int num);
147 static void ssleay_rand_add(const void *buf, int num, int add_entropy);
148 static int ssleay_rand_bytes(unsigned char *buf, int num);
149 static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num);
151 RAND_METHOD rand_ssleay_meth={
156 ssleay_rand_pseudo_bytes,
159 RAND_METHOD *RAND_SSLeay(void)
161 return(&rand_ssleay_meth);
164 static void ssleay_rand_cleanup(void)
166 memset(state,0,sizeof(state));
169 memset(md,0,MD_DIGEST_LENGTH);
175 static void ssleay_rand_add(const void *buf, int num, int add)
179 unsigned char local_md[MD_DIGEST_LENGTH];
187 * (Based on doc/ssleay.txt, section rand.doc:)
189 * The input is chopped up into units of 16 bytes (or less for
190 * the last block). Each of these blocks is run through the MD5
191 * message digest as follow: The data passed to the MD5 digest
192 * is the current 'md', the same number of bytes from the 'state'
193 * (the location determined by in incremented looping index) as
194 * the current 'block', the new key data 'block', and 'count'
195 * (which is incremented after each use).
196 * The result of this is kept in 'md' and also xored into the
197 * 'state' at the same locations that were used as input into the MD5.
200 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
203 /* use our own copies of the counters so that even
204 * if a concurrent thread seeds with exactly the
205 * same data and uses the same subarray there's _some_
207 md_c[0] = md_count[0];
208 md_c[1] = md_count[1];
210 memcpy(local_md, md, sizeof md);
212 /* state_index <= state_num <= STATE_SIZE */
214 if (state_index >= STATE_SIZE)
216 state_index%=STATE_SIZE;
217 state_num=STATE_SIZE;
219 else if (state_num < STATE_SIZE)
221 if (state_index > state_num)
222 state_num=state_index;
224 /* state_index <= state_num <= STATE_SIZE */
226 /* state[st_idx], ..., state[(st_idx + num - 1) % STATE_SIZE]
227 * are what we will use now, but other threads may use them
230 md_count[1] += (num / MD_DIGEST_LENGTH) + (num % MD_DIGEST_LENGTH > 0);
232 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
234 for (i=0; i<num; i+=MD_DIGEST_LENGTH)
237 j=(j > MD_DIGEST_LENGTH)?MD_DIGEST_LENGTH:j;
240 MD_Update(&m,local_md,MD_DIGEST_LENGTH);
241 k=(st_idx+j)-STATE_SIZE;
244 MD_Update(&m,&(state[st_idx]),j-k);
245 MD_Update(&m,&(state[0]),k);
248 MD_Update(&m,&(state[st_idx]),j);
251 MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
252 MD_Final(local_md,&m);
255 buf=(const char *)buf + j;
259 /* Parallel threads may interfere with this,
260 * but always each byte of the new state is
261 * the XOR of some previous value of its
262 * and local_md (itermediate values may be lost).
263 * Alway using locking could hurt performance more
264 * than necessary given that conflicts occur only
265 * when the total seeding is longer than the random
267 state[st_idx++]^=local_md[k];
268 if (st_idx >= STATE_SIZE)
272 memset((char *)&m,0,sizeof(m));
274 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
275 /* Don't just copy back local_md into md -- this could mean that
276 * other thread's seeding remains without effect (except for
277 * the incremented counter). By XORing it we keep at least as
278 * much entropy as fits into md. */
279 for (k = 0; k < sizeof md; k++)
281 md[k] ^= local_md[k];
283 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
286 assert(md_c[1] == md_count[1]);
291 static void ssleay_rand_seed(const void *buf, int num)
293 ssleay_rand_add(buf, num, num);
296 static int ssleay_rand_bytes(unsigned char *buf, int num)
298 int i,j,k,st_num,st_idx;
301 unsigned char local_md[MD_DIGEST_LENGTH];
305 #ifndef GETPID_IS_MEANINGLESS
306 pid_t curr_pid = getpid();
314 static unsigned char val=0;
316 for (i=0; i<num; i++)
323 * (Based on doc/ssleay.txt, section rand.doc:)
325 * For each group of 8 bytes (or less), we do the following,
327 * Input into MD5, the top 8 bytes from 'md', the byte that are
328 * to be overwritten by the random bytes and bytes from the
329 * 'state' (incrementing looping index). From this digest output
330 * (which is kept in 'md'), the top (upto) 8 bytes are
331 * returned to the caller and the bottom (upto) 8 bytes are xored
333 * Finally, after we have finished 'num' random bytes for the
334 * caller, 'count' (which is incremented) and the local and globl 'md'
335 * are fed into MD5 and the results are kept in the global 'md'.
338 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
342 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
343 /* put in some default random data, we need more than
345 RAND_add(&m,sizeof(m),0);
346 #ifndef GETPID_IS_MEANINGLESS
348 RAND_add(&l,sizeof(l),0);
350 RAND_add(&l,sizeof(l),0);
353 RAND_add(&l,sizeof(l),0);
357 * Use a random entropy pool device.
358 * Linux 1.3.x and FreeBSD-Current has
359 * this. Use /dev/urandom if you can
360 * as /dev/random will block if it runs out
363 if ((fh = fopen(DEVRANDOM, "r")) != NULL)
365 unsigned char tmpbuf[ENTROPY_NEEDED];
368 n=fread((unsigned char *)tmpbuf,1,ENTROPY_NEEDED,fh);
370 RAND_add(tmpbuf,sizeof tmpbuf,n);
375 memset(state,0,STATE_SIZE);
376 memset(md,0,MD_DIGEST_LENGTH);
378 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
382 ok = (entropy >= ENTROPY_NEEDED);
386 md_c[0] = md_count[0];
387 md_c[1] = md_count[1];
388 memcpy(local_md, md, sizeof md);
391 if (state_index > state_num)
392 state_index %= state_num;
394 /* state[st_idx], ..., state[(st_idx + num - 1) % st_num]
395 * are now ours (but other threads may use them too) */
398 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
402 j=(num >= MD_DIGEST_LENGTH/2)?MD_DIGEST_LENGTH/2:num;
405 #ifndef GETPID_IS_MEANINGLESS
406 if (curr_pid) /* just in the first iteration to save time */
408 MD_Update(&m,(unsigned char*)&curr_pid,sizeof curr_pid);
412 MD_Update(&m,&(local_md[MD_DIGEST_LENGTH/2]),MD_DIGEST_LENGTH/2);
413 MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
415 MD_Update(&m,buf,j); /* purify complains */
420 MD_Update(&m,&(state[st_idx]),j-k);
421 MD_Update(&m,&(state[0]),k);
424 MD_Update(&m,&(state[st_idx]),j);
425 MD_Final(local_md,&m);
429 state[st_idx++]^=local_md[i]; /* may compete with other threads */
430 *(buf++)=local_md[i+MD_DIGEST_LENGTH/2];
431 if (st_idx >= st_num)
437 MD_Update(&m,(unsigned char *)&(md_c[0]),sizeof(md_c));
438 MD_Update(&m,local_md,MD_DIGEST_LENGTH);
439 CRYPTO_w_lock(CRYPTO_LOCK_RAND);
440 MD_Update(&m,md,MD_DIGEST_LENGTH);
442 CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
444 memset(&m,0,sizeof(m));
449 RANDerr(RAND_F_SSLEAY_RAND_BYTES,RAND_R_PRNG_NOT_SEEDED);
454 /* pseudo-random bytes that are guaranteed to be unique but not
456 static int ssleay_rand_pseudo_bytes(unsigned char *buf, int num)
460 ret = RAND_bytes(buf, num);
463 err = ERR_peek_error();
464 if (ERR_GET_LIB(err) == ERR_LIB_RAND &&
465 ERR_GET_REASON(err) == RAND_R_PRNG_NOT_SEEDED)
466 (void)ERR_get_error();
473 #include <openssl/rand.h>
475 /*****************************************************************************
476 * Initialisation function for the SSL random generator. Takes the contents
477 * of the screen as random seed.
479 * Created 960901 by Gertjan van Oosten, gertjan@West.NL, West Consulting B.V.
482 * <URL:http://www.microsoft.com/kb/developr/win_dk/q97193.htm>;
483 * the original copyright message is:
485 * (C) Copyright Microsoft Corp. 1993. All rights reserved.
487 * You have a royalty-free right to use, modify, reproduce and
488 * distribute the Sample Files (and/or any modified version) in
489 * any way you find useful, provided that you agree that
490 * Microsoft has no warranty obligations or liability for any
491 * Sample Application Files which are modified.
494 * I have modified the loading of bytes via RAND_seed() mechanism since
495 * the origional would have been very very CPU intensive since RAND_seed()
496 * does an MD5 per 16 bytes of input. The cost to digest 16 bytes is the same
497 * as that to digest 56 bytes. So under the old system, a screen of
498 * 1024*768*256 would have been CPU cost of approximatly 49,000 56 byte MD5
499 * digests or digesting 2.7 mbytes. What I have put in place would
500 * be 48 16k MD5 digests, or efectivly 48*16+48 MD5 bytes or 816 kbytes
501 * or about 3.5 times as much.
504 void RAND_screen(void)
506 HDC hScrDC; /* screen DC */
507 HDC hMemDC; /* memory DC */
508 HBITMAP hBitmap; /* handle for our bitmap */
509 HBITMAP hOldBitmap; /* handle for previous bitmap */
510 BITMAP bm; /* bitmap properties */
511 unsigned int size; /* size of bitmap */
512 char *bmbits; /* contents of bitmap */
513 int w; /* screen width */
514 int h; /* screen height */
515 int y; /* y-coordinate of screen lines to grab */
516 int n = 16; /* number of screen lines to grab at a time */
518 /* Create a screen DC and a memory DC compatible to screen DC */
519 hScrDC = CreateDC("DISPLAY", NULL, NULL, NULL);
520 hMemDC = CreateCompatibleDC(hScrDC);
522 /* Get screen resolution */
523 w = GetDeviceCaps(hScrDC, HORZRES);
524 h = GetDeviceCaps(hScrDC, VERTRES);
526 /* Create a bitmap compatible with the screen DC */
527 hBitmap = CreateCompatibleBitmap(hScrDC, w, n);
529 /* Select new bitmap into memory DC */
530 hOldBitmap = SelectObject(hMemDC, hBitmap);
532 /* Get bitmap properties */
533 GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&bm);
534 size = (unsigned int)bm.bmWidthBytes * bm.bmHeight * bm.bmPlanes;
536 bmbits = Malloc(size);
538 /* Now go through the whole screen, repeatedly grabbing n lines */
539 for (y = 0; y < h-n; y += n)
541 unsigned char md[MD_DIGEST_LENGTH];
543 /* Bitblt screen DC to memory DC */
544 BitBlt(hMemDC, 0, 0, w, n, hScrDC, 0, y, SRCCOPY);
546 /* Copy bitmap bits from memory DC to bmbits */
547 GetBitmapBits(hBitmap, size, bmbits);
549 /* Get the MD5 of the bitmap */
552 /* Seed the random generator with the MD5 digest */
553 RAND_seed(md, MD_DIGEST_LENGTH);
559 /* Select old bitmap back into memory DC */
560 hBitmap = SelectObject(hMemDC, hOldBitmap);
563 DeleteObject(hBitmap);