* 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 32 /* require 128 bits of randomness */
+#define ENTROPY_NEEDED 20 /* require 160 bits = 20 bytes of randomness */
-#ifndef MD_RAND_DEBUG
+#ifdef MD_RAND_DEBUG
# ifndef NDEBUG
# define NDEBUG
# endif
#include <openssl/rand.h>
+#ifdef BN_DEBUG
+# define PREDICT
+#endif
+
/* #define NORAND 1 */
/* #define PREDICT 1 */
static unsigned char state[STATE_SIZE+MD_DIGEST_LENGTH];
static unsigned char md[MD_DIGEST_LENGTH];
static long md_count[2]={0,0};
-static int entropy=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, int add_entropy);
+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_cleanup,
ssleay_rand_add,
ssleay_rand_pseudo_bytes,
+ ssleay_rand_status
};
RAND_METHOD *RAND_SSLeay(void)
entropy=0;
}
-static void ssleay_rand_add(const void *buf, int num, int add)
+static void ssleay_rand_add(const void *buf, int num, double add)
{
int i,j,k,st_idx;
long md_c[2];
/*
* (Based on the rand(3) manpage)
*
- * The input is chopped up into units of 16 bytes (or less for
+ * 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 follow: The data passed to the hash function
+ * 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'
{
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
- entropy += add;
}
static void ssleay_rand_seed(const void *buf, int num)
ssleay_rand_add(buf, num, num);
}
+static void ssleay_rand_initialize(void) /* not exported in RAND_METHOD */
+ {
+ 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)
{
+ static volatile int stirred_pool = 0;
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
+ int do_stir_pool = 0;
#ifdef PREDICT
- {
- static unsigned char val=0;
+ if (rand_predictable)
+ {
+ static unsigned char val=0;
- for (i=0; i<num; i++)
- buf[i]=val++;
- return(1);
- }
+ for (i=0; i<num; i++)
+ buf[i]=val++;
+ return(1);
+ }
#endif
/*
- * (Based on doc/ssleay.txt, section rand.doc:)
+ * (Based on the rand(3) manpage:)
*
- * For each group of 8 bytes (or less), we do the following,
+ * For each group of 10 bytes (or less), we do the following:
*
- * Input into MD5, the top 8 bytes from 'md', the byte that are
- * to be overwritten by the random bytes and bytes from the
+ * 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 (upto) 8 bytes are
- * returned to the caller and the bottom (upto) 8 bytes are xored
+ * (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 globl 'md'
- * are fed into MD5 and the results are kept in the global 'md'.
+ * 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 (init)
+ if (!initialized)
+ ssleay_rand_initialize();
+
+ if (!stirred_pool)
+ do_stir_pool = 1;
+
+ ok = (entropy >= ENTROPY_NEEDED);
+ if (!ok)
{
- CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
- /* put in some default random data, we need more than
- * just this */
- RAND_add(&m,sizeof(m),0);
-#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);
+ /* 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.
+ *
+ * NOTE: This approach fails if the program forks before
+ * we have enough entropy. Entropy should be collected
+ * in a separate input pool and be transferred to the
+ * output pool only when the entropy limit has been reached.
+ */
+ entropy -= num;
+ if (entropy < 0)
+ entropy = 0;
+ }
-#ifdef DEVRANDOM
- /*
- * Use a random entropy pool device.
- * Linux 1.3.x and FreeBSD-Current has
- * this. Use /dev/urandom if you can
- * as /dev/random will block if it runs out
- * of random entries.
+ if (do_stir_pool)
+ {
+ /* Our output function chains only half of 'md', so we better
+ * make sure that the required entropy gets 'evenly distributed'
+ * through 'state', our randomness pool. The input function
+ * (ssleay_rand_add) chains all of 'md', which makes it more
+ * suitable for this purpose.
*/
- if ((fh = fopen(DEVRANDOM, "r")) != NULL)
- {
- unsigned char tmpbuf[ENTROPY_NEEDED];
- int n;
- 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);
+ int n = STATE_SIZE; /* so that the complete pool gets accessed */
+ while (n > 0)
+ {
+#if MD_DIGEST_LENGTH > 20
+# error "Please adjust DUMMY_SEED."
#endif
- CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- init=0;
+#define DUMMY_SEED "...................." /* at least MD_DIGEST_LENGTH */
+ /* Note that the seed does not matter, it's just that
+ * ssleay_rand_add expects to have something to hash. */
+ ssleay_rand_add(DUMMY_SEED, MD_DIGEST_LENGTH, 0.0);
+ n -= MD_DIGEST_LENGTH;
+ }
+ if (ok)
+ stirred_pool = 1;
}
- ok = (entropy >= ENTROPY_NEEDED);
-
st_idx=state_index;
st_num=state_num;
md_c[0] = md_count[0];
else
{
RANDerr(RAND_F_SSLEAY_RAND_BYTES,RAND_R_PRNG_NOT_SEEDED);
+ ERR_add_error_data(1, "You need to read the OpenSSL FAQ, "
+ "http://www.openssl.org/support/faq.html");
return(0);
}
}
return (ret);
}
-#ifdef WINDOWS
-#include <windows.h>
-#include <openssl/rand.h>
+static int ssleay_rand_status(void)
+ {
+ int ret;
-/*****************************************************************************
- * 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 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);
- }
+ CRYPTO_w_lock(CRYPTO_LOCK_RAND);
- Free(bmbits);
- }
+ if (!initialized)
+ ssleay_rand_initialize();
+ ret = entropy >= ENTROPY_NEEDED;
- /* Select old bitmap back into memory DC */
- hBitmap = SelectObject(hMemDC, hOldBitmap);
+ CRYPTO_w_unlock(CRYPTO_LOCK_RAND);
- /* Clean up */
- DeleteObject(hBitmap);
- DeleteDC(hMemDC);
- DeleteDC(hScrDC);
-}
-#endif
+ return ret;
+ }
projects / openssl.git / blobdiff