RetroZilla/security/nss/lib/freebl/mpi/utils/exptmod.c
2015-10-20 23:03:22 -04:00

84 lines
2.6 KiB
C

/*
* exptmod.c
*
* Command line tool to perform modular exponentiation on arbitrary
* precision integers.
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the MPI Arbitrary Precision Integer Arithmetic library.
*
* The Initial Developer of the Original Code is
* Michael J. Fromberger.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
/* $Id: exptmod.c,v 1.3 2004/04/27 23:04:37 gerv%gerv.net Exp $ */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "mpi.h"
int main(int argc, char *argv[])
{
mp_int a, b, m;
mp_err res;
char *str;
int len, rval = 0;
if(argc < 3) {
fprintf(stderr, "Usage: %s <a> <b> <m>\n", argv[0]);
return 1;
}
mp_init(&a); mp_init(&b); mp_init(&m);
mp_read_radix(&a, argv[1], 10);
mp_read_radix(&b, argv[2], 10);
mp_read_radix(&m, argv[3], 10);
if((res = mp_exptmod(&a, &b, &m, &a)) != MP_OKAY) {
fprintf(stderr, "%s: error: %s\n", argv[0], mp_strerror(res));
rval = 1;
} else {
len = mp_radix_size(&a, 10);
str = calloc(len, sizeof(char));
mp_toradix(&a, str, 10);
printf("%s\n", str);
free(str);
}
mp_clear(&a); mp_clear(&b); mp_clear(&m);
return rval;
}