release/src/router/nettle/rsa-sha256-verify.c

   1 /* rsa-sha256-verify.c
   2  *
   3  * Verifying signatures created with RSA and SHA256.
   4  */
   5
   6 /* nettle, low-level cryptographics library
   7  *
   8  * Copyright (C) 2001, 2003, 2006 Niels Möller
   9  *
  10  * The nettle library is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU Lesser General Public License as published by
  12  * the Free Software Foundation; either version 2.1 of the License, or (at your
  13  * option) any later version.
  14  *
  15  * The nettle library is distributed in the hope that it will be useful, but
  16  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  17  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  18  * License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General Public License
  21  * along with the nettle library; see the file COPYING.LIB.  If not, write to
  22  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  23  * MA 02111-1301, USA.
  24  */
  25
  26 #if HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include <assert.h>
  31
  32 #include "rsa.h"
  33
  34 #include "bignum.h"
  35 #include "pkcs1.h"
  36
  37 int
  38 rsa_sha256_verify(const struct rsa_public_key *key,
  39                   struct sha256_ctx *hash,
  40                   const mpz_t s)
  41 {
  42   int res;
  43   mpz_t m;
  44
  45   mpz_init(m);
  46
  47   res = (pkcs1_rsa_sha256_encode(m, key->size, hash)
  48          &&_rsa_verify(key, m, s));
  49
  50   mpz_clear(m);
  51
  52   return res;
  53 }
  54
  55 int
  56 rsa_sha256_verify_digest(const struct rsa_public_key *key,
  57                          const uint8_t *digest,
  58                          const mpz_t s)
  59 {
  60   int res;
  61   mpz_t m;
  62
  63   mpz_init(m);
  64
  65   res = (pkcs1_rsa_sha256_encode_digest(m, key->size, digest)
  66          && _rsa_verify(key, m, s));
  67
  68   mpz_clear(m);
  69
  70   return res;
  71 }