1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
/*
* Diffie-Hellman-Merkle key exchange (prime generation)
*
* Copyright (C) 2006-2012, 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"
#include "polarssl/entropy.h"
#include "polarssl/ctr_drbg.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"
#if !defined(POLARSSL_BIGNUM_C) || !defined(POLARSSL_ENTROPY_C) || \
!defined(POLARSSL_FS_IO) || !defined(POLARSSL_CTR_DRBG_C) || \
!defined(POLARSSL_GENPRIME)
int main( int argc, char *argv[] )
{
((void) argc);
((void) argv);
printf("POLARSSL_BIGNUM_C and/or POLARSSL_ENTROPY_C and/or "
"POLARSSL_FS_IO and/or POLARSSL_CTR_DRBG_C and/or "
"POLARSSL_GENPRIME not defined.\n");
return( 0 );
}
#else
int main( int argc, char *argv[] )
{
int ret = 1;
mpi G, P, Q;
entropy_context entropy;
ctr_drbg_context ctr_drbg;
const char *pers = "dh_genprime";
FILE *fout;
((void) argc);
((void) argv);
mpi_init( &G ); mpi_init( &P ); mpi_init( &Q );
entropy_init( &entropy );
if( ( ret = mpi_read_string( &G, 10, GENERATOR ) ) != 0 )
{
printf( " failed\n ! mpi_read_string returned %d\n", ret );
goto exit;
}
printf( "\nWARNING: You should not generate and use your own DHM primes\n" );
printf( " unless you are very certain of what you are doing!\n" );
printf( " Failing to follow this instruction may result in\n" );
printf( " weak security for your connections! Use the\n" );
printf( " predefined DHM parameters from dhm.h instead!\n\n" );
printf( "============================================================\n\n" );
printf( " ! Generating large primes may take minutes!\n" );
printf( "\n . Seeding the random number generator..." );
fflush( stdout );
if( ( ret = ctr_drbg_init( &ctr_drbg, entropy_func, &entropy,
(const unsigned char *) pers,
strlen( pers ) ) ) != 0 )
{
printf( " failed\n ! ctr_drbg_init returned %d\n", ret );
goto exit;
}
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,
ctr_drbg_random, &ctr_drbg ) ) != 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, ctr_drbg_random, &ctr_drbg ) ) != 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( &G ); mpi_free( &P ); mpi_free( &Q );
ctr_drbg_free( &ctr_drbg );
entropy_free( &entropy );
#if defined(_WIN32)
printf( " Press Enter to exit this program.\n" );
fflush( stdout ); getchar();
#endif
return( ret );
}
#endif /* POLARSSL_BIGNUM_C && POLARSSL_ENTROPY_C && POLARSSL_FS_IO &&
POLARSSL_CTR_DRBG_C && POLARSSL_GENPRIME */
|
