diff options
Diffstat (limited to 'security/nss/lib/freebl/mpi/utils/bbs_rand.c')
-rw-r--r-- | security/nss/lib/freebl/mpi/utils/bbs_rand.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/security/nss/lib/freebl/mpi/utils/bbs_rand.c b/security/nss/lib/freebl/mpi/utils/bbs_rand.c new file mode 100644 index 000000000..fed2fe2e6 --- /dev/null +++ b/security/nss/lib/freebl/mpi/utils/bbs_rand.c @@ -0,0 +1,65 @@ +/* + * Blum, Blum & Shub PRNG using the MPI library + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "bbs_rand.h" + +#define SEED 1 +#define MODULUS 2 + +/* This modulus is the product of two randomly generated 512-bit + prime integers, each of which is congruent to 3 (mod 4). */ +static char *bbs_modulus = + "75A2A6E1D27393B86562B9CE7279A8403CB4258A637DAB5233465373E37837383EDC" + "332282B8575927BC4172CE8C147B4894050EE9D2BDEED355C121037270CA2570D127" + "7D2390CD1002263326635CC6B259148DE3A1A03201980A925E395E646A5E9164B0EC" + "28559EBA58C87447245ADD0651EDA507056A1129E3A3E16E903D64B437"; + +static int bbs_init = 0; /* flag set when library is initialized */ +static mp_int bbs_state; /* the current state of the generator */ + +/* Suggested size of random seed data */ +int bbs_seed_size = (sizeof(bbs_modulus) / 2); + +void +bbs_srand(unsigned char *data, int len) +{ + if ((bbs_init & SEED) == 0) { + mp_init(&bbs_state); + bbs_init |= SEED; + } + + mp_read_raw(&bbs_state, (char *)data, len); + +} /* end bbs_srand() */ + +unsigned int +bbs_rand(void) +{ + static mp_int modulus; + unsigned int result = 0, ix; + + if ((bbs_init & MODULUS) == 0) { + mp_init(&modulus); + mp_read_radix(&modulus, bbs_modulus, 16); + bbs_init |= MODULUS; + } + + for (ix = 0; ix < sizeof(unsigned int); ix++) { + mp_digit d; + + mp_sqrmod(&bbs_state, &modulus, &bbs_state); + d = DIGIT(&bbs_state, 0); + + result = (result << CHAR_BIT) | (d & UCHAR_MAX); + } + + return result; + +} /* end bbs_rand() */ + +/*------------------------------------------------------------------------*/ +/* HERE THERE BE DRAGONS */ |