1 /*
2 * Example RSA key generation program
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 *
7 * This file is provided under the Apache License 2.0, or the
8 * GNU General Public License v2.0 or later.
9 *
10 * **********
11 * Apache License 2.0:
12 *
13 * Licensed under the Apache License, Version 2.0 (the "License"); you may
14 * not use this file except in compliance with the License.
15 * You may obtain a copy of the License at
16 *
17 * http://www.apache.org/licenses/LICENSE-2.0
18 *
19 * Unless required by applicable law or agreed to in writing, software
20 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
21 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
22 * See the License for the specific language governing permissions and
23 * limitations under the License.
24 *
25 * **********
26 *
27 * **********
28 * GNU General Public License v2.0 or later:
29 *
30 * This program is free software; you can redistribute it and/or modify
31 * it under the terms of the GNU General Public License as published by
32 * the Free Software Foundation; either version 2 of the License, or
33 * (at your option) any later version.
34 *
35 * This program is distributed in the hope that it will be useful,
36 * but WITHOUT ANY WARRANTY; without even the implied warranty of
37 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
38 * GNU General Public License for more details.
39 *
40 * You should have received a copy of the GNU General Public License along
41 * with this program; if not, write to the Free Software Foundation, Inc.,
42 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
43 *
44 * **********
45 */
46
47 #if !defined(MBEDTLS_CONFIG_FILE)
48 #include "mbedtls/config.h"
49 #else
50 #include MBEDTLS_CONFIG_FILE
51 #endif
52
53 #if defined(MBEDTLS_PLATFORM_C)
54 #include "mbedtls/platform.h"
55 #else
56 #include <stdio.h>
57 #include <stdlib.h>
58 #define mbedtls_printf printf
59 #define mbedtls_exit exit
60 #define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
61 #define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
62 #endif /* MBEDTLS_PLATFORM_C */
63
64 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_ENTROPY_C) && \
65 defined(MBEDTLS_RSA_C) && defined(MBEDTLS_GENPRIME) && \
66 defined(MBEDTLS_FS_IO) && defined(MBEDTLS_CTR_DRBG_C)
67 #include "mbedtls/entropy.h"
68 #include "mbedtls/ctr_drbg.h"
69 #include "mbedtls/bignum.h"
70 #include "mbedtls/x509.h"
71 #include "mbedtls/rsa.h"
72
73 #include <stdio.h>
74 #include <string.h>
75 #endif
76
77 #define KEY_SIZE 2048
78 #define EXPONENT 65537
79
80 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) || \
81 !defined(MBEDTLS_RSA_C) || !defined(MBEDTLS_GENPRIME) || \
82 !defined(MBEDTLS_FS_IO) || !defined(MBEDTLS_CTR_DRBG_C)
main(void)83 int main( void )
84 {
85 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
86 "MBEDTLS_RSA_C and/or MBEDTLS_GENPRIME and/or "
87 "MBEDTLS_FS_IO and/or MBEDTLS_CTR_DRBG_C not defined.\n");
88 mbedtls_exit( 0 );
89 }
90 #else
91
92
main(void)93 int main( void )
94 {
95 int ret = 1;
96 int exit_code = MBEDTLS_EXIT_FAILURE;
97 mbedtls_rsa_context rsa;
98 mbedtls_entropy_context entropy;
99 mbedtls_ctr_drbg_context ctr_drbg;
100 mbedtls_mpi N, P, Q, D, E, DP, DQ, QP;
101 FILE *fpub = NULL;
102 FILE *fpriv = NULL;
103 const char *pers = "rsa_genkey";
104
105 mbedtls_ctr_drbg_init( &ctr_drbg );
106 mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
107 mbedtls_mpi_init( &N ); mbedtls_mpi_init( &P ); mbedtls_mpi_init( &Q );
108 mbedtls_mpi_init( &D ); mbedtls_mpi_init( &E ); mbedtls_mpi_init( &DP );
109 mbedtls_mpi_init( &DQ ); mbedtls_mpi_init( &QP );
110
111 mbedtls_printf( "\n . Seeding the random number generator..." );
112 fflush( stdout );
113
114 mbedtls_entropy_init( &entropy );
115 if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
116 (const unsigned char *) pers,
117 strlen( pers ) ) ) != 0 )
118 {
119 mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret );
120 goto exit;
121 }
122
123 mbedtls_printf( " ok\n . Generating the RSA key [ %d-bit ]...", KEY_SIZE );
124 fflush( stdout );
125
126 if( ( ret = mbedtls_rsa_gen_key( &rsa, mbedtls_ctr_drbg_random, &ctr_drbg, KEY_SIZE,
127 EXPONENT ) ) != 0 )
128 {
129 mbedtls_printf( " failed\n ! mbedtls_rsa_gen_key returned %d\n\n", ret );
130 goto exit;
131 }
132
133 mbedtls_printf( " ok\n . Exporting the public key in rsa_pub.txt...." );
134 fflush( stdout );
135
136 if( ( ret = mbedtls_rsa_export ( &rsa, &N, &P, &Q, &D, &E ) ) != 0 ||
137 ( ret = mbedtls_rsa_export_crt( &rsa, &DP, &DQ, &QP ) ) != 0 )
138 {
139 mbedtls_printf( " failed\n ! could not export RSA parameters\n\n" );
140 goto exit;
141 }
142
143 if( ( fpub = fopen( "rsa_pub.txt", "wb+" ) ) == NULL )
144 {
145 mbedtls_printf( " failed\n ! could not open rsa_pub.txt for writing\n\n" );
146 goto exit;
147 }
148
149 if( ( ret = mbedtls_mpi_write_file( "N = ", &N, 16, fpub ) ) != 0 ||
150 ( ret = mbedtls_mpi_write_file( "E = ", &E, 16, fpub ) ) != 0 )
151 {
152 mbedtls_printf( " failed\n ! mbedtls_mpi_write_file returned %d\n\n", ret );
153 goto exit;
154 }
155
156 mbedtls_printf( " ok\n . Exporting the private key in rsa_priv.txt..." );
157 fflush( stdout );
158
159 if( ( fpriv = fopen( "rsa_priv.txt", "wb+" ) ) == NULL )
160 {
161 mbedtls_printf( " failed\n ! could not open rsa_priv.txt for writing\n" );
162 goto exit;
163 }
164
165 if( ( ret = mbedtls_mpi_write_file( "N = " , &N , 16, fpriv ) ) != 0 ||
166 ( ret = mbedtls_mpi_write_file( "E = " , &E , 16, fpriv ) ) != 0 ||
167 ( ret = mbedtls_mpi_write_file( "D = " , &D , 16, fpriv ) ) != 0 ||
168 ( ret = mbedtls_mpi_write_file( "P = " , &P , 16, fpriv ) ) != 0 ||
169 ( ret = mbedtls_mpi_write_file( "Q = " , &Q , 16, fpriv ) ) != 0 ||
170 ( ret = mbedtls_mpi_write_file( "DP = ", &DP, 16, fpriv ) ) != 0 ||
171 ( ret = mbedtls_mpi_write_file( "DQ = ", &DQ, 16, fpriv ) ) != 0 ||
172 ( ret = mbedtls_mpi_write_file( "QP = ", &QP, 16, fpriv ) ) != 0 )
173 {
174 mbedtls_printf( " failed\n ! mbedtls_mpi_write_file returned %d\n\n", ret );
175 goto exit;
176 }
177 /*
178 mbedtls_printf( " ok\n . Generating the certificate..." );
179
180 x509write_init_raw( &cert );
181 x509write_add_pubkey( &cert, &rsa );
182 x509write_add_subject( &cert, "CN='localhost'" );
183 x509write_add_validity( &cert, "2007-09-06 17:00:32",
184 "2010-09-06 17:00:32" );
185 x509write_create_selfsign( &cert, &rsa );
186 x509write_crtfile( &cert, "cert.der", X509_OUTPUT_DER );
187 x509write_crtfile( &cert, "cert.pem", X509_OUTPUT_PEM );
188 x509write_free_raw( &cert );
189 */
190 mbedtls_printf( " ok\n\n" );
191
192 exit_code = MBEDTLS_EXIT_SUCCESS;
193
194 exit:
195
196 if( fpub != NULL )
197 fclose( fpub );
198
199 if( fpriv != NULL )
200 fclose( fpriv );
201
202 mbedtls_mpi_free( &N ); mbedtls_mpi_free( &P ); mbedtls_mpi_free( &Q );
203 mbedtls_mpi_free( &D ); mbedtls_mpi_free( &E ); mbedtls_mpi_free( &DP );
204 mbedtls_mpi_free( &DQ ); mbedtls_mpi_free( &QP );
205 mbedtls_rsa_free( &rsa );
206 mbedtls_ctr_drbg_free( &ctr_drbg );
207 mbedtls_entropy_free( &entropy );
208
209 #if defined(_WIN32)
210 mbedtls_printf( " Press Enter to exit this program.\n" );
211 fflush( stdout ); getchar();
212 #endif
213
214 mbedtls_exit( exit_code );
215 }
216 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_RSA_C &&
217 MBEDTLS_GENPRIME && MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */
218