| /* |
| * Diffie-Hellman-Merkle key exchange (prime generation) |
| * |
| * Based on XySSL: Copyright (C) 2006-2008 Christophe Devine |
| * |
| * Copyright (C) 2009 Paul Bakker <polarssl_maintainer at polarssl dot org> |
| * |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * * Neither the names of PolarSSL or XySSL nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED |
| * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #ifndef _CRT_SECURE_NO_DEPRECATE |
| #define _CRT_SECURE_NO_DEPRECATE 1 |
| #endif |
| |
| #include <stdio.h> |
| |
| #include "polarssl/bignum.h" |
| #include "polarssl/config.h" |
| #include "polarssl/havege.h" |
| |
| /* |
| * Note: G = 4 is always a quadratic residue mod P, |
| * so it is a generator of order Q (with P = 2*Q+1). |
| */ |
| #define DH_P_SIZE 1024 |
| #define GENERATOR "4" |
| |
| int main( void ) |
| { |
| int ret = 1; |
| |
| #if defined(POLARSSL_GENPRIME) |
| mpi G, P, Q; |
| havege_state hs; |
| FILE *fout; |
| |
| mpi_init( &G, &P, &Q, NULL ); |
| mpi_read_string( &G, 10, GENERATOR ); |
| |
| printf( "\n . Seeding the random number generator..." ); |
| fflush( stdout ); |
| |
| havege_init( &hs ); |
| |
| printf( " ok\n . Generating the modulus, please wait..." ); |
| fflush( stdout ); |
| |
| /* |
| * This can take a long time... |
| */ |
| if( ( ret = mpi_gen_prime( &P, DH_P_SIZE, 1, |
| havege_rand, &hs ) ) != 0 ) |
| { |
| printf( " failed\n ! mpi_gen_prime returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| printf( " ok\n . Verifying that Q = (P-1)/2 is prime..." ); |
| fflush( stdout ); |
| |
| if( ( ret = mpi_sub_int( &Q, &P, 1 ) ) != 0 ) |
| { |
| printf( " failed\n ! mpi_sub_int returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| if( ( ret = mpi_div_int( &Q, NULL, &Q, 2 ) ) != 0 ) |
| { |
| printf( " failed\n ! mpi_div_int returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| if( ( ret = mpi_is_prime( &Q, havege_rand, &hs ) ) != 0 ) |
| { |
| printf( " failed\n ! mpi_is_prime returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| printf( " ok\n . Exporting the value in dh_prime.txt..." ); |
| fflush( stdout ); |
| |
| if( ( fout = fopen( "dh_prime.txt", "wb+" ) ) == NULL ) |
| { |
| ret = 1; |
| printf( " failed\n ! Could not create dh_prime.txt\n\n" ); |
| goto exit; |
| } |
| |
| if( ( ret = mpi_write_file( "P = ", &P, 16, fout ) != 0 ) || |
| ( ret = mpi_write_file( "G = ", &G, 16, fout ) != 0 ) ) |
| { |
| printf( " failed\n ! mpi_write_file returned %d\n\n", ret ); |
| goto exit; |
| } |
| |
| printf( " ok\n\n" ); |
| fclose( fout ); |
| |
| exit: |
| |
| mpi_free( &Q, &P, &G, NULL ); |
| #else |
| printf( "\n ! Prime-number generation is not available.\n\n" ); |
| #endif |
| |
| #ifdef WIN32 |
| printf( " Press Enter to exit this program.\n" ); |
| fflush( stdout ); getchar(); |
| #endif |
| |
| return( ret ); |
| } |