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 #if defined(MBEDTLS_PLATFORM_C)
23 #include "mbedtls/platform.h"
24 #else
25 #include <stdio.h>
26 #include <stdlib.h>
27 #define mbedtls_fprintf fprintf
28 #define mbedtls_printf printf
29 #define mbedtls_exit exit
30 #define MBEDTLS_EXIT_SUCCESS EXIT_SUCCESS
31 #define MBEDTLS_EXIT_FAILURE EXIT_FAILURE
32 #endif /* MBEDTLS_PLATFORM_C */
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)
37 #include "mbedtls/rsa.h"
38 #include "mbedtls/entropy.h"
39 #include "mbedtls/ctr_drbg.h"
40
41 #include <string.h>
42 #endif
43
44 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_RSA_C) || \
45 !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_FS_IO) || \
46 !defined(MBEDTLS_CTR_DRBG_C)
main(void)47 int main( void )
48 {
49 mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_RSA_C and/or "
50 "MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO and/or "
51 "MBEDTLS_CTR_DRBG_C not defined.\n");
52 mbedtls_exit( 0 );
53 }
54 #else
55
56
main(int argc,char * argv[])57 int main( int argc, char *argv[] )
58 {
59 FILE *f;
60 int ret = 1;
61 int exit_code = MBEDTLS_EXIT_FAILURE;
62 size_t i;
63 mbedtls_rsa_context rsa;
64 mbedtls_entropy_context entropy;
65 mbedtls_ctr_drbg_context ctr_drbg;
66 unsigned char input[1024];
67 unsigned char buf[512];
68 const char *pers = "rsa_encrypt";
69 mbedtls_mpi N, E;
70
71 if( argc != 2 )
72 {
73 mbedtls_printf( "usage: rsa_encrypt <string of max 100 characters>\n" );
74
75 #if defined(_WIN32)
76 mbedtls_printf( "\n" );
77 #endif
78
79 mbedtls_exit( exit_code );
80 }
81
82 mbedtls_printf( "\n . Seeding the random number generator..." );
83 fflush( stdout );
84
85 mbedtls_mpi_init( &N ); mbedtls_mpi_init( &E );
86 mbedtls_rsa_init( &rsa );
87 mbedtls_ctr_drbg_init( &ctr_drbg );
88 mbedtls_entropy_init( &entropy );
89
90 ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
91 &entropy, (const unsigned char *) pers,
92 strlen( pers ) );
93 if( ret != 0 )
94 {
95 mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n",
96 ret );
97 goto exit;
98 }
99
100 mbedtls_printf( "\n . Reading public key from rsa_pub.txt" );
101 fflush( stdout );
102
103 if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL )
104 {
105 mbedtls_printf( " failed\n ! Could not open rsa_pub.txt\n" \
106 " ! Please run rsa_genkey first\n\n" );
107 goto exit;
108 }
109
110 if( ( ret = mbedtls_mpi_read_file( &N, 16, f ) ) != 0 ||
111 ( ret = mbedtls_mpi_read_file( &E, 16, f ) ) != 0 )
112 {
113 mbedtls_printf( " failed\n ! mbedtls_mpi_read_file returned %d\n\n",
114 ret );
115 fclose( f );
116 goto exit;
117 }
118 fclose( f );
119
120 if( ( ret = mbedtls_rsa_import( &rsa, &N, NULL, NULL, NULL, &E ) ) != 0 )
121 {
122 mbedtls_printf( " failed\n ! mbedtls_rsa_import returned %d\n\n",
123 ret );
124 goto exit;
125 }
126
127 if( strlen( argv[1] ) > 100 )
128 {
129 mbedtls_printf( " Input data larger than 100 characters.\n\n" );
130 goto exit;
131 }
132
133 memcpy( input, argv[1], strlen( argv[1] ) );
134
135 /*
136 * Calculate the RSA encryption of the hash.
137 */
138 mbedtls_printf( "\n . Generating the RSA encrypted value" );
139 fflush( stdout );
140
141 ret = mbedtls_rsa_pkcs1_encrypt( &rsa, mbedtls_ctr_drbg_random,
142 &ctr_drbg, strlen( argv[1] ), input, buf );
143 if( ret != 0 )
144 {
145 mbedtls_printf( " failed\n ! mbedtls_rsa_pkcs1_encrypt returned %d\n\n",
146 ret );
147 goto exit;
148 }
149
150 /*
151 * Write the signature into result-enc.txt
152 */
153 if( ( f = fopen( "result-enc.txt", "wb+" ) ) == NULL )
154 {
155 mbedtls_printf( " failed\n ! Could not create %s\n\n", "result-enc.txt" );
156 goto exit;
157 }
158
159 for( i = 0; i < rsa.MBEDTLS_PRIVATE(len); i++ )
160 mbedtls_fprintf( f, "%02X%s", buf[i],
161 ( i + 1 ) % 16 == 0 ? "\r\n" : " " );
162
163 fclose( f );
164
165 mbedtls_printf( "\n . Done (created \"%s\")\n\n", "result-enc.txt" );
166
167 exit_code = MBEDTLS_EXIT_SUCCESS;
168
169 exit:
170 mbedtls_mpi_free( &N ); mbedtls_mpi_free( &E );
171 mbedtls_ctr_drbg_free( &ctr_drbg );
172 mbedtls_entropy_free( &entropy );
173 mbedtls_rsa_free( &rsa );
174
175 #if defined(_WIN32)
176 mbedtls_printf( " + Press Enter to exit this program.\n" );
177 fflush( stdout ); getchar();
178 #endif
179
180 mbedtls_exit( exit_code );
181 }
182 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_RSA_C && MBEDTLS_ENTROPY_C &&
183 MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */
184