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diff --git a/core/lib/libtomcrypt/src/math/rand_prime.c b/core/lib/libtomcrypt/src/math/rand_prime.c
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+/*
+ * Copyright (c) 2001-2007, Tom St Denis
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER 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.
+ */
+
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis
+ *
+ * LibTomCrypt is a library that provides various cryptographic
+ * algorithms in a highly modular and flexible manner.
+ *
+ * The library is free for all purposes without any express
+ * guarantee it works.
+ *
+ * Tom St Denis, tomstdenis@gmail.com, http://libtom.org
+ */
+#include "tomcrypt.h"
+
+#if !defined LTC_NO_MATH && !defined LTC_NO_PRNGS
+
+/**
+ @file rand_prime.c
+ Generate a random prime, Tom St Denis
+*/
+
+#define USE_BBS 1
+
+int rand_prime(void *N, long len, prng_state *prng, int wprng)
+{
+ int err, res, type;
+ unsigned char *buf;
+
+ LTC_ARGCHK(N != NULL);
+
+ /* get type */
+ if (len < 0) {
+ type = USE_BBS;
+ len = -len;
+ } else {
+ type = 0;
+ }
+
+ /* allow sizes between 2 and 512 bytes for a prime size */
+ if (len < 2 || len > 512) {
+ return CRYPT_INVALID_PRIME_SIZE;
+ }
+
+ /* valid PRNG? Better be! */
+ if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
+ return err;
+ }
+
+ /* allocate buffer to work with */
+ buf = XCALLOC(1, len);
+ if (buf == NULL) {
+ return CRYPT_MEM;
+ }
+
+ do {
+ /* generate value */
+ if (prng_descriptor[wprng]->read(buf, len, prng) != (unsigned long)len) {
+ XFREE(buf);
+ return CRYPT_ERROR_READPRNG;
+ }
+
+ /* munge bits */
+ buf[0] |= 0x80 | 0x40;
+ buf[len-1] |= 0x01 | ((type & USE_BBS) ? 0x02 : 0x00);
+
+ /* load value */
+ if ((err = mp_read_unsigned_bin(N, buf, len)) != CRYPT_OK) {
+ XFREE(buf);
+ return err;
+ }
+
+ /* test */
+ if ((err = mp_prime_is_prime(N, 8, &res)) != CRYPT_OK) {
+ XFREE(buf);
+ return err;
+ }
+ } while (res == LTC_MP_NO);
+
+#ifdef LTC_CLEAN_STACK
+ zeromem(buf, len);
+#endif
+
+ XFREE(buf);
+ return CRYPT_OK;
+}
+
+#endif /* LTC_NO_MATH */
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/math/rand_prime.c,v $ */
+/* $Revision: 1.7 $ */
+/* $Date: 2006/12/28 01:27:23 $ */