1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/security/nss/lib/freebl/mpi/utils/bbs_rand.c Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,63 @@
1.4 +/*
1.5 + * Blum, Blum & Shub PRNG using the MPI library
1.6 + *
1.7 + * This Source Code Form is subject to the terms of the Mozilla Public
1.8 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.9 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.10 +
1.11 +#include "bbs_rand.h"
1.12 +
1.13 +#define SEED 1
1.14 +#define MODULUS 2
1.15 +
1.16 +/* This modulus is the product of two randomly generated 512-bit
1.17 + prime integers, each of which is congruent to 3 (mod 4). */
1.18 +static char *bbs_modulus =
1.19 +"75A2A6E1D27393B86562B9CE7279A8403CB4258A637DAB5233465373E37837383EDC"
1.20 +"332282B8575927BC4172CE8C147B4894050EE9D2BDEED355C121037270CA2570D127"
1.21 +"7D2390CD1002263326635CC6B259148DE3A1A03201980A925E395E646A5E9164B0EC"
1.22 +"28559EBA58C87447245ADD0651EDA507056A1129E3A3E16E903D64B437";
1.23 +
1.24 +static int bbs_init = 0; /* flag set when library is initialized */
1.25 +static mp_int bbs_state; /* the current state of the generator */
1.26 +
1.27 +/* Suggested size of random seed data */
1.28 +int bbs_seed_size = (sizeof(bbs_modulus) / 2);
1.29 +
1.30 +void bbs_srand(unsigned char *data, int len)
1.31 +{
1.32 + if((bbs_init & SEED) == 0) {
1.33 + mp_init(&bbs_state);
1.34 + bbs_init |= SEED;
1.35 + }
1.36 +
1.37 + mp_read_raw(&bbs_state, (char *)data, len);
1.38 +
1.39 +} /* end bbs_srand() */
1.40 +
1.41 +unsigned int bbs_rand(void)
1.42 +{
1.43 + static mp_int modulus;
1.44 + unsigned int result = 0, ix;
1.45 +
1.46 + if((bbs_init & MODULUS) == 0) {
1.47 + mp_init(&modulus);
1.48 + mp_read_radix(&modulus, bbs_modulus, 16);
1.49 + bbs_init |= MODULUS;
1.50 + }
1.51 +
1.52 + for(ix = 0; ix < sizeof(unsigned int); ix++) {
1.53 + mp_digit d;
1.54 +
1.55 + mp_sqrmod(&bbs_state, &modulus, &bbs_state);
1.56 + d = DIGIT(&bbs_state, 0);
1.57 +
1.58 + result = (result << CHAR_BIT) | (d & UCHAR_MAX);
1.59 + }
1.60 +
1.61 + return result;
1.62 +
1.63 +} /* end bbs_rand() */
1.64 +
1.65 +/*------------------------------------------------------------------------*/
1.66 +/* HERE THERE BE DRAGONS */
