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-rw-r--r--libtomcrypt/src/misc/mpi/rand_prime.c70
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diff --git a/libtomcrypt/src/misc/mpi/rand_prime.c b/libtomcrypt/src/misc/mpi/rand_prime.c
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+/* 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://libtomcrypt.org
+ */
+#include "tomcrypt.h"
+
+/**
+ @file rand_prime.c
+ Generate a random prime, Tom St Denis
+*/
+#ifdef MPI
+
+struct rng_data {
+ prng_state *prng;
+ int wprng;
+};
+
+static int rand_prime_helper(unsigned char *dst, int len, void *dat)
+{
+ return (int)prng_descriptor[((struct rng_data *)dat)->wprng].read(dst, len, ((struct rng_data *)dat)->prng);
+}
+
+int rand_prime(mp_int *N, long len, prng_state *prng, int wprng)
+{
+ struct rng_data rng;
+ int type, err;
+
+ LTC_ARGCHK(N != NULL);
+
+ /* allow sizes between 2 and 256 bytes for a prime size */
+ if (len < 16 || len > 4096) {
+ return CRYPT_INVALID_PRIME_SIZE;
+ }
+
+ /* valid PRNG? Better be! */
+ if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
+ return err;
+ }
+
+ /* setup our callback data, then world domination! */
+ rng.prng = prng;
+ rng.wprng = wprng;
+
+ /* get type */
+ if (len < 0) {
+ type = LTM_PRIME_BBS;
+ len = -len;
+ } else {
+ type = 0;
+ }
+ type |= LTM_PRIME_2MSB_ON;
+
+ /* New prime generation makes the code even more cryptoish-insane. Do you know what this means!!!
+ -- Gir: Yeah, oh wait, er, no.
+ */
+ return mpi_to_ltc_error(mp_prime_random_ex(N, mp_prime_rabin_miller_trials(len), len, type, rand_prime_helper, &rng));
+}
+
+#endif
+
+
+/* $Source: /cvs/libtom/libtomcrypt/src/misc/mpi/rand_prime.c,v $ */
+/* $Revision: 1.3 $ */
+/* $Date: 2005/05/05 14:35:59 $ */