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salsa20-internal.h
dsa-keygen.c 5.12 KiB
/* dsa-keygen.c
*
* Generation of DSA keypairs
*/
/* nettle, low-level cryptographics library
*
* Copyright (C) 2002 Niels Mller
*
* The nettle library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or (at your
* option) any later version.
*
* The nettle library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with the nettle library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
* MA 02111-1307, USA.
*/
#if HAVE_CONFIG_H
#include "config.h"
#endif
#if WITH_PUBLIC_KEY
#include "dsa.h"
#include "bignum.h"
#include "memxor.h"
#include <stdlib.h>
/* The (slow) NIST method of generating DSA primes. Algorithm 4.56 of
* Handbook of Applied Cryptography. */
#define SEED_LENGTH SHA1_DIGEST_SIZE
#define SEED_BITS (SEED_LENGTH * 8)
static void
hash(mpz_t x, uint8_t *digest)
{
mpz_t t;
uint8_t data[SEED_LENGTH];
struct sha1_ctx ctx;
mpz_init_set(t, x);
mpz_fdiv_r_2exp(t, t, SEED_BITS);
nettle_mpz_get_str_256(SEED_LENGTH, data, t);
mpz_clear(t);
sha1_init(&ctx);
sha1_update(&ctx, SEED_LENGTH, data);
sha1_digest(&ctx, SHA1_DIGEST_SIZE, digest);
}
static void
dsa_nist_gen(mpz_t p, mpz_t q,
void *random_ctx, nettle_random_func random,
void *progress_ctx, nettle_progress_func progress,
unsigned L)
{
unsigned n;
unsigned b;