diff options
Diffstat (limited to 'external/nettle-3.3/nettle/rsa-verify.c')
-rw-r--r-- | external/nettle-3.3/nettle/rsa-verify.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/external/nettle-3.3/nettle/rsa-verify.c b/external/nettle-3.3/nettle/rsa-verify.c new file mode 100644 index 0000000..8484a85 --- /dev/null +++ b/external/nettle-3.3/nettle/rsa-verify.c @@ -0,0 +1,64 @@ +/* rsa-verify.c + + Verifying RSA signatures. + + Copyright (C) 2001, 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 3 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" +#endif + +#include "rsa.h" + +#include "bignum.h" + +int +_rsa_verify(const struct rsa_public_key *key, + const mpz_t m, + const mpz_t s) +{ + int res; + + mpz_t m1; + + if ( (mpz_sgn(s) <= 0) + || (mpz_cmp(s, key->n) >= 0) ) + return 0; + + mpz_init(m1); + + mpz_powm(m1, s, key->e, key->n); + + res = !mpz_cmp(m, m1); + + mpz_clear(m1); + + return res; +} |