Update copyright headers for dual licensing.

[gd/nettle] / dsa-verify.c

diff --git a/dsa-verify.c b/dsa-verify.c
index 89232e8feb66381a46bda41f64108301f8527008..cc984bd31a22c6c20a395b7bcf680ce1e912b4d5 100644 (file)
--- a/dsa-verify.c
+++ b/dsa-verify.c
@@ -1,27 +1,35 @@
 /* dsa-verify.c
- *
- * The DSA publickey algorithm.
- */
-
-/* nettle, low-level cryptographics library
- *
- * Copyright (C) 2002, 2003 Niels Möller
- *  
- * 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., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02111-1301, USA.
- */
+
+   The DSA publickey algorithm.
+
+   Copyright (C) 2002, 2003 Niels Möller
+
+   This file is part of GNU Nettle.
+
+   GNU Nettle is free software: you can redistribute it and/or
+   modify it under the terms of either:
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at your
+       option) any later version.
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at your
+       option) any later version.
+
+   or both in parallel, as here.
+
+   GNU Nettle 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
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see http://www.gnu.org/licenses/.
+*/
 
 #if HAVE_CONFIG_H
 # include "config.h"
@@ -34,10 +42,11 @@
 #include "bignum.h"
 
 int
-_dsa_verify(const struct dsa_public_key *key,
-           size_t digest_size,
-           const uint8_t *digest,
-           const struct dsa_signature *signature)
+dsa_verify(const struct dsa_params *params,
+          const mpz_t y,
+          size_t digest_size,
+          const uint8_t *digest,
+          const struct dsa_signature *signature)
 {
   mpz_t w;
   mpz_t tmp;
@@ -46,10 +55,10 @@ _dsa_verify(const struct dsa_public_key *key,
   int res;
 
   /* Check that r and s are in the proper range */
-  if (mpz_sgn(signature->r) <= 0 || mpz_cmp(signature->r, key->q) >= 0)
+  if (mpz_sgn(signature->r) <= 0 || mpz_cmp(signature->r, params->q) >= 0)
     return 0;
 
-  if (mpz_sgn(signature->s) <= 0 || mpz_cmp(signature->s, key->q) >= 0)
+  if (mpz_sgn(signature->s) <= 0 || mpz_cmp(signature->s, params->q) >= 0)
     return 0;
 
   mpz_init(w);
@@ -58,7 +67,7 @@ _dsa_verify(const struct dsa_public_key *key,
 
   /* NOTE: In gmp-2, mpz_invert sometimes generates negative inverses,
    * so we need gmp-3 or better. */
-  if (!mpz_invert(w, signature->s, key->q))
+  if (!mpz_invert(w, signature->s, params->q))
     {
       mpz_clear(w);
       return 0;
@@ -68,25 +77,25 @@ _dsa_verify(const struct dsa_public_key *key,
   mpz_init(v);
 
   /* The message digest */
-  _dsa_hash (tmp, mpz_sizeinbase (key->q, 2), digest_size, digest);
+  _dsa_hash (tmp, mpz_sizeinbase (params->q, 2), digest_size, digest);
   
   /* v = g^{w * h (mod q)} (mod p)  */
   mpz_mul(tmp, tmp, w);
-  mpz_fdiv_r(tmp, tmp, key->q);
+  mpz_fdiv_r(tmp, tmp, params->q);
 
-  mpz_powm(v, key->g, tmp, key->p);
+  mpz_powm(v, params->g, tmp, params->p);
 
   /* y^{w * r (mod q) } (mod p) */
   mpz_mul(tmp, signature->r, w);
-  mpz_fdiv_r(tmp, tmp, key->q);
+  mpz_fdiv_r(tmp, tmp, params->q);
 
-  mpz_powm(tmp, key->y, tmp, key->p);
+  mpz_powm(tmp, y, tmp, params->p);
 
   /* v = (g^{w * h} * y^{w * r} (mod p) ) (mod q) */
   mpz_mul(v, v, tmp);
-  mpz_fdiv_r(v, v, key->p);
+  mpz_fdiv_r(v, v, params->p);
 
-  mpz_fdiv_r(v, v, key->q);
+  mpz_fdiv_r(v, v, params->q);
 
   res = !mpz_cmp(v, signature->r);