1 /*
2 * Example RSA key generation program
3 *
4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 *
19 * This file is part of mbed TLS (https://tls.mbed.org)
20 */
21
22 #if !defined(MBEDTLS_CONFIG_FILE)
23 #include "mbedtls/config.h"
24 #else
25 #include MBEDTLS_CONFIG_FILE
26 #endif
27
28 #if defined(MBEDTLS_PLATFORM_C)
29 #include "mbedtls/platform.h"
30 #else
31 #include <stdio.h>
32 #define mbedtls_printf printf
33 #endif
34
35 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_ENTROPY_C) && \
36 defined(MBEDTLS_RSA_C) && defined(MBEDTLS_GENPRIME) && \
37 defined(MBEDTLS_FS_IO) && defined(MBEDTLS_CTR_DRBG_C)
38 #include "mbedtls/entropy.h"
39 #include "mbedtls/ctr_drbg.h"
40 #include "mbedtls/bignum.h"
41 #include "mbedtls/x509.h"
42 #include "mbedtls/rsa.h"
43
44 #include <stdio.h>
45 #include <string.h>
46 #endif
47
48 #define KEY_SIZE 2048
49 #define EXPONENT 65537
50
51 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) || \
52 !defined(MBEDTLS_RSA_C) || !defined(MBEDTLS_GENPRIME) || \
53 !defined(MBEDTLS_FS_IO) || !defined(MBEDTLS_CTR_DRBG_C)
main(void)54 int main( void )
55 {
56 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
57 "MBEDTLS_RSA_C and/or MBEDTLS_GENPRIME and/or "
58 "MBEDTLS_FS_IO and/or MBEDTLS_CTR_DRBG_C not defined.\n");
59 return( 0 );
60 }
61 #else
main(void)62 int main( void )
63 {
64 int ret;
65 mbedtls_rsa_context rsa;
66 mbedtls_entropy_context entropy;
67 mbedtls_ctr_drbg_context ctr_drbg;
68 FILE *fpub = NULL;
69 FILE *fpriv = NULL;
70 const char *pers = "rsa_genkey";
71
72 mbedtls_ctr_drbg_init( &ctr_drbg );
73
74 mbedtls_printf( "\n . Seeding the random number generator..." );
75 fflush( stdout );
76
77 mbedtls_entropy_init( &entropy );
78 if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,
79 (const unsigned char *) pers,
80 strlen( pers ) ) ) != 0 )
81 {
82 mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret );
83 goto exit;
84 }
85
86 mbedtls_printf( " ok\n . Generating the RSA key [ %d-bit ]...", KEY_SIZE );
87 fflush( stdout );
88
89 mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 );
90
91 if( ( ret = mbedtls_rsa_gen_key( &rsa, mbedtls_ctr_drbg_random, &ctr_drbg, KEY_SIZE,
92 EXPONENT ) ) != 0 )
93 {
94 mbedtls_printf( " failed\n ! mbedtls_rsa_gen_key returned %d\n\n", ret );
95 goto exit;
96 }
97
98 mbedtls_printf( " ok\n . Exporting the public key in rsa_pub.txt...." );
99 fflush( stdout );
100
101 if( ( fpub = fopen( "rsa_pub.txt", "wb+" ) ) == NULL )
102 {
103 mbedtls_printf( " failed\n ! could not open rsa_pub.txt for writing\n\n" );
104 ret = 1;
105 goto exit;
106 }
107
108 if( ( ret = mbedtls_mpi_write_file( "N = ", &rsa.N, 16, fpub ) ) != 0 ||
109 ( ret = mbedtls_mpi_write_file( "E = ", &rsa.E, 16, fpub ) ) != 0 )
110 {
111 mbedtls_printf( " failed\n ! mbedtls_mpi_write_file returned %d\n\n", ret );
112 goto exit;
113 }
114
115 mbedtls_printf( " ok\n . Exporting the private key in rsa_priv.txt..." );
116 fflush( stdout );
117
118 if( ( fpriv = fopen( "rsa_priv.txt", "wb+" ) ) == NULL )
119 {
120 mbedtls_printf( " failed\n ! could not open rsa_priv.txt for writing\n" );
121 ret = 1;
122 goto exit;
123 }
124
125 if( ( ret = mbedtls_mpi_write_file( "N = " , &rsa.N , 16, fpriv ) ) != 0 ||
126 ( ret = mbedtls_mpi_write_file( "E = " , &rsa.E , 16, fpriv ) ) != 0 ||
127 ( ret = mbedtls_mpi_write_file( "D = " , &rsa.D , 16, fpriv ) ) != 0 ||
128 ( ret = mbedtls_mpi_write_file( "P = " , &rsa.P , 16, fpriv ) ) != 0 ||
129 ( ret = mbedtls_mpi_write_file( "Q = " , &rsa.Q , 16, fpriv ) ) != 0 ||
130 ( ret = mbedtls_mpi_write_file( "DP = ", &rsa.DP, 16, fpriv ) ) != 0 ||
131 ( ret = mbedtls_mpi_write_file( "DQ = ", &rsa.DQ, 16, fpriv ) ) != 0 ||
132 ( ret = mbedtls_mpi_write_file( "QP = ", &rsa.QP, 16, fpriv ) ) != 0 )
133 {
134 mbedtls_printf( " failed\n ! mbedtls_mpi_write_file returned %d\n\n", ret );
135 goto exit;
136 }
137 /*
138 mbedtls_printf( " ok\n . Generating the certificate..." );
139
140 x509write_init_raw( &cert );
141 x509write_add_pubkey( &cert, &rsa );
142 x509write_add_subject( &cert, "CN='localhost'" );
143 x509write_add_validity( &cert, "2007-09-06 17:00:32",
144 "2010-09-06 17:00:32" );
145 x509write_create_selfsign( &cert, &rsa );
146 x509write_crtfile( &cert, "cert.der", X509_OUTPUT_DER );
147 x509write_crtfile( &cert, "cert.pem", X509_OUTPUT_PEM );
148 x509write_free_raw( &cert );
149 */
150 mbedtls_printf( " ok\n\n" );
151
152 exit:
153
154 if( fpub != NULL )
155 fclose( fpub );
156
157 if( fpriv != NULL )
158 fclose( fpriv );
159
160 mbedtls_rsa_free( &rsa );
161 mbedtls_ctr_drbg_free( &ctr_drbg );
162 mbedtls_entropy_free( &entropy );
163
164 #if defined(_WIN32)
165 mbedtls_printf( " Press Enter to exit this program.\n" );
166 fflush( stdout ); getchar();
167 #endif
168
169 return( ret );
170 }
171 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_RSA_C &&
172 MBEDTLS_GENPRIME && MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */
173