mbedtls/programs/pkey/mpi_demo.c
2014-04-30 16:40:20 +02:00

102 lines
3 KiB
C

/*
* Simple MPI demonstration program
*
* Copyright (C) 2006-2011, Brainspark B.V.
*
* This file is part of PolarSSL (http://www.polarssl.org)
* Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of 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.
*
* This program 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 a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#if !defined(POLARSSL_CONFIG_FILE)
#include "polarssl/config.h"
#else
#include POLARSSL_CONFIG_FILE
#endif
#include <stdio.h>
#include "polarssl/bignum.h"
#if !defined(POLARSSL_BIGNUM_C) || !defined(POLARSSL_FS_IO)
int main( int argc, char *argv[] )
{
((void) argc);
((void) argv);
printf("POLARSSL_BIGNUM_C and/or POLARSSL_FS_IO not defined.\n");
return( 0 );
}
#else
int main( int argc, char *argv[] )
{
mpi E, P, Q, N, H, D, X, Y, Z;
((void) argc);
((void) argv);
mpi_init( &E ); mpi_init( &P ); mpi_init( &Q ); mpi_init( &N );
mpi_init( &H ); mpi_init( &D ); mpi_init( &X ); mpi_init( &Y );
mpi_init( &Z );
mpi_read_string( &P, 10, "2789" );
mpi_read_string( &Q, 10, "3203" );
mpi_read_string( &E, 10, "257" );
mpi_mul_mpi( &N, &P, &Q );
printf( "\n Public key:\n\n" );
mpi_write_file( " N = ", &N, 10, NULL );
mpi_write_file( " E = ", &E, 10, NULL );
printf( "\n Private key:\n\n" );
mpi_write_file( " P = ", &P, 10, NULL );
mpi_write_file( " Q = ", &Q, 10, NULL );
#if defined(POLARSSL_GENPRIME)
mpi_sub_int( &P, &P, 1 );
mpi_sub_int( &Q, &Q, 1 );
mpi_mul_mpi( &H, &P, &Q );
mpi_inv_mod( &D, &E, &H );
mpi_write_file( " D = E^-1 mod (P-1)*(Q-1) = ",
&D, 10, NULL );
#else
printf("\nTest skipped (POLARSSL_GENPRIME not defined).\n\n");
#endif
mpi_read_string( &X, 10, "55555" );
mpi_exp_mod( &Y, &X, &E, &N, NULL );
mpi_exp_mod( &Z, &Y, &D, &N, NULL );
printf( "\n RSA operation:\n\n" );
mpi_write_file( " X (plaintext) = ", &X, 10, NULL );
mpi_write_file( " Y (ciphertext) = X^E mod N = ", &Y, 10, NULL );
mpi_write_file( " Z (decrypted) = Y^D mod N = ", &Z, 10, NULL );
printf( "\n" );
mpi_free( &E ); mpi_free( &P ); mpi_free( &Q ); mpi_free( &N );
mpi_free( &H ); mpi_free( &D ); mpi_free( &X ); mpi_free( &Y );
mpi_free( &Z );
#if defined(_WIN32)
printf( " Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( 0 );
}
#endif /* POLARSSL_BIGNUM_C && POLARSSL_FS_IO */