1 /*
2 * RSA simple data encryption program
3 *
4 * Copyright The Mbed TLS Contributors
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
20 #include "mbedtls/build_info.h"
21
22 #include "mbedtls/platform.h"
23
24 #if defined(MBEDTLS_BIGNUM_C) && defined(MBEDTLS_RSA_C) && \
25 defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_FS_IO) && \
26 defined(MBEDTLS_CTR_DRBG_C)
27 #include "mbedtls/rsa.h"
28 #include "mbedtls/entropy.h"
29 #include "mbedtls/ctr_drbg.h"
30
31 #include <string.h>
32 #endif
33
34 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) || \
35 !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_FS_IO) || \
36 !defined(MBEDTLS_CTR_DRBG_C)
main(void)37 int main( void )
38 {
39 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
40 "MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO and/or "
41 "MBEDTLS_CTR_DRBG_C not defined.\n");
42 mbedtls_exit( 0 );
43 }
44 #else
45
46
main(int argc,char * argv[])47 int main( int argc, char *argv[] )
48 {
49 FILE *f;
50 int ret = 1;
51 int exit_code = MBEDTLS_EXIT_FAILURE;
52 size_t i;
53 mbedtls_rsa_context rsa;
54 mbedtls_entropy_context entropy;
55 mbedtls_ctr_drbg_context ctr_drbg;
56 unsigned char input[1024];
57 unsigned char buf[512];
58 const char *pers = "rsa_encrypt";
59 mbedtls_mpi N, E;
60
61 if( argc != 2 )
62 {
63 mbedtls_printf( "usage: rsa_encrypt <string of max 100 characters>\n" );
64
65 #if defined(_WIN32)
66 mbedtls_printf( "\n" );
67 #endif
68
69 mbedtls_exit( exit_code );
70 }
71
72 mbedtls_printf( "\n . Seeding the random number generator..." );
73 fflush( stdout );
74
75 mbedtls_mpi_init( &N ); mbedtls_mpi_init( &E );
76 mbedtls_rsa_init( &rsa );
77 mbedtls_ctr_drbg_init( &ctr_drbg );
78 mbedtls_entropy_init( &entropy );
79
80 ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
81 &entropy, (const unsigned char *) pers,
82 strlen( pers ) );
83 if( ret != 0 )
84 {
85 mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n",
86 ret );
87 goto exit;
88 }
89
90 mbedtls_printf( "\n . Reading public key from rsa_pub.txt" );
91 fflush( stdout );
92
93 if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL )
94 {
95 mbedtls_printf( " failed\n ! Could not open rsa_pub.txt\n" \
96 " ! Please run rsa_genkey first\n\n" );
97 goto exit;
98 }
99
100 if( ( ret = mbedtls_mpi_read_file( &N, 16, f ) ) != 0 ||
101 ( ret = mbedtls_mpi_read_file( &E, 16, f ) ) != 0 )
102 {
103 mbedtls_printf( " failed\n ! mbedtls_mpi_read_file returned %d\n\n",
104 ret );
105 fclose( f );
106 goto exit;
107 }
108 fclose( f );
109
110 if( ( ret = mbedtls_rsa_import( &rsa, &N, NULL, NULL, NULL, &E ) ) != 0 )
111 {
112 mbedtls_printf( " failed\n ! mbedtls_rsa_import returned %d\n\n",
113 ret );
114 goto exit;
115 }
116
117 if( strlen( argv[1] ) > 100 )
118 {
119 mbedtls_printf( " Input data larger than 100 characters.\n\n" );
120 goto exit;
121 }
122
123 memcpy( input, argv[1], strlen( argv[1] ) );
124
125 /*
126 * Calculate the RSA encryption of the hash.
127 */
128 mbedtls_printf( "\n . Generating the RSA encrypted value" );
129 fflush( stdout );
130
131 ret = mbedtls_rsa_pkcs1_encrypt( &rsa, mbedtls_ctr_drbg_random,
132 &ctr_drbg, strlen( argv[1] ), input, buf );
133 if( ret != 0 )
134 {
135 mbedtls_printf( " failed\n ! mbedtls_rsa_pkcs1_encrypt returned %d\n\n",
136 ret );
137 goto exit;
138 }
139
140 /*
141 * Write the signature into result-enc.txt
142 */
143 if( ( f = fopen( "result-enc.txt", "wb+" ) ) == NULL )
144 {
145 mbedtls_printf( " failed\n ! Could not create %s\n\n", "result-enc.txt" );
146 goto exit;
147 }
148
149 for( i = 0; i < rsa.MBEDTLS_PRIVATE(len); i++ )
150 mbedtls_fprintf( f, "%02X%s", buf[i],
151 ( i + 1 ) % 16 == 0 ? "\r\n" : " " );
152
153 fclose( f );
154
155 mbedtls_printf( "\n . Done (created \"%s\")\n\n", "result-enc.txt" );
156
157 exit_code = MBEDTLS_EXIT_SUCCESS;
158
159 exit:
160 mbedtls_mpi_free( &N ); mbedtls_mpi_free( &E );
161 mbedtls_ctr_drbg_free( &ctr_drbg );
162 mbedtls_entropy_free( &entropy );
163 mbedtls_rsa_free( &rsa );
164
165 mbedtls_exit( exit_code );
166 }
167 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_ENTROPY_C &&
168 MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */
169
