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_PK_PARSE_C) && \
35     defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_FS_IO) && \
36     defined(MBEDTLS_CTR_DRBG_C)
37 #include "mbedtls/error.h"
38 #include "mbedtls/pk.h"
39 #include "mbedtls/entropy.h"
40 #include "mbedtls/ctr_drbg.h"
41 
42 #include <stdio.h>
43 #include <string.h>
44 #endif
45 
46 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_PK_PARSE_C) ||  \
47     !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_FS_IO) || \
48     !defined(MBEDTLS_CTR_DRBG_C)
main(void)49 int main( void )
50 {
51     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_PK_PARSE_C and/or "
52            "MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO and/or "
53            "MBEDTLS_CTR_DRBG_C not defined.\n");
54     mbedtls_exit( 0 );
55 }
56 #else
57 
58 
main(int argc,char * argv[])59 int main( int argc, char *argv[] )
60 {
61     FILE *f;
62     int ret = 1;
63     int exit_code = MBEDTLS_EXIT_FAILURE;
64     size_t i, olen = 0;
65     mbedtls_pk_context pk;
66     mbedtls_entropy_context entropy;
67     mbedtls_ctr_drbg_context ctr_drbg;
68     unsigned char input[1024];
69     unsigned char buf[512];
70     const char *pers = "mbedtls_pk_encrypt";
71 
72     mbedtls_ctr_drbg_init( &ctr_drbg );
73     mbedtls_entropy_init( &entropy );
74     mbedtls_pk_init( &pk );
75 
76     if( argc != 3 )
77     {
78         mbedtls_printf( "usage: mbedtls_pk_encrypt <key_file> <string of max 100 characters>\n" );
79 
80 #if defined(_WIN32)
81         mbedtls_printf( "\n" );
82 #endif
83 
84         goto exit;
85     }
86 
87     mbedtls_printf( "\n  . Seeding the random number generator..." );
88     fflush( stdout );
89 
90     if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func,
91                                        &entropy, (const unsigned char *) pers,
92                                        strlen( pers ) ) ) != 0 )
93     {
94         mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned -0x%04x\n",
95                         (unsigned int) -ret );
96         goto exit;
97     }
98 
99     mbedtls_printf( "\n  . Reading public key from '%s'", argv[1] );
100     fflush( stdout );
101 
102     if( ( ret = mbedtls_pk_parse_public_keyfile( &pk, argv[1] ) ) != 0 )
103     {
104         mbedtls_printf( " failed\n  ! mbedtls_pk_parse_public_keyfile returned -0x%04x\n", (unsigned int) -ret );
105         goto exit;
106     }
107 
108     if( strlen( argv[2] ) > 100 )
109     {
110         mbedtls_printf( " Input data larger than 100 characters.\n\n" );
111         goto exit;
112     }
113 
114     memcpy( input, argv[2], strlen( argv[2] ) );
115 
116     /*
117      * Calculate the RSA encryption of the hash.
118      */
119     mbedtls_printf( "\n  . Generating the encrypted value" );
120     fflush( stdout );
121 
122     if( ( ret = mbedtls_pk_encrypt( &pk, input, strlen( argv[2] ),
123                             buf, &olen, sizeof(buf),
124                             mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )
125     {
126         mbedtls_printf( " failed\n  ! mbedtls_pk_encrypt returned -0x%04x\n",
127                         (unsigned int) -ret );
128         goto exit;
129     }
130 
131     /*
132      * Write the signature into result-enc.txt
133      */
134     if( ( f = fopen( "result-enc.txt", "wb+" ) ) == NULL )
135     {
136         mbedtls_printf( " failed\n  ! Could not create %s\n\n",
137                         "result-enc.txt" );
138         ret = 1;
139         goto exit;
140     }
141 
142     for( i = 0; i < olen; i++ )
143     {
144         mbedtls_fprintf( f, "%02X%s", buf[i],
145                  ( i + 1 ) % 16 == 0 ? "\r\n" : " " );
146     }
147 
148     fclose( f );
149 
150     mbedtls_printf( "\n  . Done (created \"%s\")\n\n", "result-enc.txt" );
151 
152     exit_code = MBEDTLS_EXIT_SUCCESS;
153 
154 exit:
155 
156     mbedtls_pk_free( &pk );
157     mbedtls_entropy_free( &entropy );
158     mbedtls_ctr_drbg_free( &ctr_drbg );
159 
160 #if defined(MBEDTLS_ERROR_C)
161     if( exit_code != MBEDTLS_EXIT_SUCCESS )
162     {
163         mbedtls_strerror( ret, (char *) buf, sizeof( buf ) );
164         mbedtls_printf( "  !  Last error was: %s\n", buf );
165     }
166 #endif
167 
168 #if defined(_WIN32)
169     mbedtls_printf( "  + Press Enter to exit this program.\n" );
170     fflush( stdout ); getchar();
171 #endif
172 
173     mbedtls_exit( exit_code );
174 }
175 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_PK_PARSE_C && MBEDTLS_ENTROPY_C &&
176           MBEDTLS_FS_IO && MBEDTLS_CTR_DRBG_C */
177