Mercurial > dropbear

comparison rand_prime.c @ 3:7faae8f46238 libtomcrypt-orig

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Branch renaming
author Matt Johnston <matt@ucc.asn.au>
date Mon, 31 May 2004 18:25:41 +0000
parents
children 6362d3854bb4
comparison
equal deleted inserted replaced
-1:000000000000 3:7faae8f46238
1 /* LibTomCrypt, modular cryptographic library -- Tom St Denis
2 *
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
5 *
6 * The library is free for all purposes without any express
7 * guarantee it works.
8 *
9 * Tom St Denis, [email protected], http://libtomcrypt.org
10 */
11 #include "mycrypt.h"
12
13 #ifdef MPI
14
15 struct rng_data {
16 prng_state *prng;
17 int wprng;
18 };
19
20 static int rand_prime_helper(unsigned char *dst, int len, void *dat)
21 {
22 return (int)prng_descriptor[((struct rng_data *)dat)->wprng].read(dst, len, ((struct rng_data *)dat)->prng);
23 }
24
25 int rand_prime(mp_int *N, long len, prng_state *prng, int wprng)
26 {
27 struct rng_data rng;
28 int type, err;
29
30 _ARGCHK(N != NULL);
31
32 /* allow sizes between 2 and 256 bytes for a prime size */
33 if (len < 16 || len > 4096) {
34 return CRYPT_INVALID_PRIME_SIZE;
35 }
36
37 /* valid PRNG? Better be! */
38 if ((err = prng_is_valid(wprng)) != CRYPT_OK) {
39 return err;
40 }
41
42 /* setup our callback data, then world domination! */
43 rng.prng = prng;
44 rng.wprng = wprng;
45
46 /* get type */
47 if (len < 0) {
48 type = LTM_PRIME_BBS;
49 len = -len;
50 } else {
51 type = 0;
52 }
53
54 /* New prime generation makes the code even more cryptoish-insane. Do you know what this means!!!
55 -- Gir: Yeah, oh wait, er, no.
56 */
57 if ((err = mp_prime_random_ex(N, mp_prime_rabin_miller_trials(len), len, type, rand_prime_helper, &rng)) != MP_OKAY) {
58 return mpi_to_ltc_error(err);
59 }
60
61 return CRYPT_OK;
62 }
63
64 #endif
65