* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
+/* ====================================================================
+ * Copyright (c) 1998-2001 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).
+ *
+ */
+
+
#include <stdio.h>
#include <time.h>
#include "cryptlib.h"
#include "bn_lcl.h"
#include <openssl/rand.h>
+#include <openssl/sha.h>
static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom)
{
bytes=(bits+7)/8;
bit=(bits-1)%8;
- mask=0xff<<bit;
+ mask=0xff<<(bit+1);
buf=(unsigned char *)OPENSSL_malloc(bytes);
if (buf == NULL)
{
- BNerr(BN_F_BN_RAND,ERR_R_MALLOC_FAILURE);
+ BNerr(BN_F_BNRAND,ERR_R_MALLOC_FAILURE);
goto err;
}
/* make a random number and set the top and bottom bits */
time(&tim);
- RAND_add(&tim,sizeof(tim),0);
+ RAND_add(&tim,sizeof(tim),0.0);
if (pseudorand)
{
}
#endif
- if (top)
+ if (top != -1)
{
- if (bit == 0)
+ if (top)
{
- buf[0]=1;
- buf[1]|=0x80;
+ if (bit == 0)
+ {
+ buf[0]=1;
+ buf[1]|=0x80;
+ }
+ else
+ {
+ buf[0]|=(3<<(bit-1));
+ }
}
else
{
- buf[0]|=(3<<(bit-1));
- buf[0]&= ~(mask<<1);
+ buf[0]|=(1<<bit);
}
}
- else
- {
- buf[0]|=(1<<bit);
- buf[0]&= ~(mask<<1);
- }
- if (bottom) /* set bottom bits to whatever odd is */
+ buf[0] &= ~mask;
+ if (bottom) /* set bottom bit if requested */
buf[bytes-1]|=1;
if (!BN_bin2bn(buf,bytes,rnd)) goto err;
ret=1;
err:
if (buf != NULL)
{
- memset(buf,0,bytes);
+ OPENSSL_cleanse(buf,bytes);
OPENSSL_free(buf);
}
+ bn_check_top(rnd);
return(ret);
}
}
#endif
-/* random number r: min <= r < min+range */
-int BN_rand_range(BIGNUM *r, BIGNUM *min, BIGNUM *range)
+
+/* random number r: 0 <= r < range */
+static int bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range)
{
+ int (*bn_rand)(BIGNUM *, int, int, int) = pseudo ? BN_pseudo_rand : BN_rand;
int n;
+ int count = 100;
if (range->neg || BN_is_zero(range))
{
n = BN_num_bits(range); /* n > 0 */
+ /* BN_is_bit_set(range, n - 1) always holds */
+
if (n == 1)
+ BN_zero(r);
+ else if (!BN_is_bit_set(range, n - 2) && !BN_is_bit_set(range, n - 3))
{
- if (!BN_zero(r)) return 0;
- }
- else if (BN_is_bit_set(range, n - 2))
- {
- do
- {
- /* range = 11..._2, so each iteration succeeds with probability > .75 */
- if (!BN_rand(r, n, 0, 0)) return 0;
- }
- while (BN_cmp(r, range) >= 0);
- }
- else
- {
- /* range = 10..._2,
+ /* range = 100..._2,
* so 3*range (= 11..._2) is exactly one bit longer than range */
do
{
- if (!BN_rand(r, n + 1, 0, 0)) return 0;
+ if (!bn_rand(r, n + 1, -1, 0)) return 0;
/* If r < 3*range, use r := r MOD range
* (which is either r, r - range, or r - 2*range).
* Otherwise, iterate once more.
* Since 3*range = 11..._2, each iteration succeeds with
- * probability > .75. */
+ * probability >= .75. */
if (BN_cmp(r ,range) >= 0)
{
if (!BN_sub(r, r, range)) return 0;
if (BN_cmp(r, range) >= 0)
if (!BN_sub(r, r, range)) return 0;
}
+
+ if (!--count)
+ {
+ BNerr(BN_F_BN_RAND_RANGE, BN_R_TOO_MANY_ITERATIONS);
+ return 0;
+ }
+
}
while (BN_cmp(r, range) >= 0);
}
-
- if (min != NULL)
+ else
{
- if (!BN_add(r, r, min)) return 0;
+ do
+ {
+ /* range = 11..._2 or range = 101..._2 */
+ if (!bn_rand(r, n, -1, 0)) return 0;
+
+ if (!--count)
+ {
+ BNerr(BN_F_BN_RAND_RANGE, BN_R_TOO_MANY_ITERATIONS);
+ return 0;
+ }
+ }
+ while (BN_cmp(r, range) >= 0);
}
-
+
+ bn_check_top(r);
return 1;
}
+
+
+int BN_rand_range(BIGNUM *r, const BIGNUM *range)
+ {
+ return bn_rand_range(0, r, range);
+ }
+
+int BN_pseudo_rand_range(BIGNUM *r, const BIGNUM *range)
+ {
+ return bn_rand_range(1, r, range);
+ }
+
+#ifndef OPENSSL_NO_SHA512
+/* BN_generate_dsa_nonce generates a random number 0 <= out < range. Unlike
+ * BN_rand_range, it also includes the contents of |priv| and |message| in the
+ * generation so that an RNG failure isn't fatal as long as |priv| remains
+ * secret. This is intended for use in DSA and ECDSA where an RNG weakness
+ * leads directly to private key exposure unless this function is used. */
+int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, const BIGNUM* priv,
+ const unsigned char *message, size_t message_len,
+ BN_CTX *ctx)
+ {
+ SHA512_CTX sha;
+ /* We use 512 bits of random data per iteration to
+ * ensure that we have at least |range| bits of randomness. */
+ unsigned char random_bytes[64];
+ unsigned char digest[SHA512_DIGEST_LENGTH];
+ unsigned done, todo;
+ /* We generate |range|+8 bytes of random output. */
+ const unsigned num_k_bytes = BN_num_bytes(range) + 8;
+ unsigned char private_bytes[96];
+ unsigned char *k_bytes;
+ int ret = 0;
+
+ k_bytes = OPENSSL_malloc(num_k_bytes);
+ if (!k_bytes)
+ goto err;
+
+ /* We copy |priv| into a local buffer to avoid exposing its length. */
+ todo = sizeof(priv->d[0])*priv->top;
+ if (todo > sizeof(private_bytes))
+ {
+ /* No reasonable DSA or ECDSA key should have a private key
+ * this large and we don't handle this case in order to avoid
+ * leaking the length of the private key. */
+ BNerr(BN_F_BN_GENERATE_DSA_NONCE, BN_R_PRIVATE_KEY_TOO_LARGE);
+ goto err;
+ }
+ memcpy(private_bytes, priv->d, todo);
+ memset(private_bytes + todo, 0, sizeof(private_bytes) - todo);
+
+ for (done = 0; done < num_k_bytes;) {
+ if (RAND_bytes(random_bytes, sizeof(random_bytes)) != 1)
+ goto err;
+ SHA512_Init(&sha);
+ SHA512_Update(&sha, &done, sizeof(done));
+ SHA512_Update(&sha, private_bytes, sizeof(private_bytes));
+ SHA512_Update(&sha, message, message_len);
+ SHA512_Update(&sha, random_bytes, sizeof(random_bytes));
+ SHA512_Final(digest, &sha);
+
+ todo = num_k_bytes - done;
+ if (todo > SHA512_DIGEST_LENGTH)
+ todo = SHA512_DIGEST_LENGTH;
+ memcpy(k_bytes + done, digest, todo);
+ done += todo;
+ }
+
+ if (!BN_bin2bn(k_bytes, num_k_bytes, out))
+ goto err;
+ if (BN_mod(out, out, range, ctx) != 1)
+ goto err;
+ ret = 1;
+
+err:
+ if (k_bytes)
+ OPENSSL_free(k_bytes);
+ return ret;
+ }
+#endif /* OPENSSL_NO_SHA512 */