1 /**
2 * \brief Use and generate random data into a file via the CTR_DBRG based on AES
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_CTR_DRBG_C) && defined(MBEDTLS_ENTROPY_C) && \
25 defined(MBEDTLS_FS_IO)
26 #include "mbedtls/entropy.h"
27 #include "mbedtls/ctr_drbg.h"
28
29 #include <stdio.h>
30 #endif
31
32 #if !defined(MBEDTLS_CTR_DRBG_C) || !defined(MBEDTLS_ENTROPY_C) || \
33 !defined(MBEDTLS_FS_IO)
main(void)34 int main( void )
35 {
36 mbedtls_printf("MBEDTLS_CTR_DRBG_C and/or MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO not defined.\n");
37 mbedtls_exit( 0 );
38 }
39 #else
40
41
main(int argc,char * argv[])42 int main( int argc, char *argv[] )
43 {
44 FILE *f;
45 int i, k, ret = 1;
46 int exit_code = MBEDTLS_EXIT_FAILURE;
47 mbedtls_ctr_drbg_context ctr_drbg;
48 mbedtls_entropy_context entropy;
49 unsigned char buf[1024];
50
51 mbedtls_ctr_drbg_init( &ctr_drbg );
52
53 if( argc < 2 )
54 {
55 mbedtls_fprintf( stderr, "usage: %s <output filename>\n", argv[0] );
56 mbedtls_exit( exit_code );
57 }
58
59 if( ( f = fopen( argv[1], "wb+" ) ) == NULL )
60 {
61 mbedtls_printf( "failed to open '%s' for writing.\n", argv[1] );
62 mbedtls_exit( exit_code );
63 }
64
65 mbedtls_entropy_init( &entropy );
66 ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy, (const unsigned char *) "RANDOM_GEN", 10 );
67 if( ret != 0 )
68 {
69 mbedtls_printf( "failed in mbedtls_ctr_drbg_seed: %d\n", ret );
70 goto cleanup;
71 }
72 mbedtls_ctr_drbg_set_prediction_resistance( &ctr_drbg, MBEDTLS_CTR_DRBG_PR_OFF );
73
74 #if defined(MBEDTLS_FS_IO)
75 ret = mbedtls_ctr_drbg_update_seed_file( &ctr_drbg, "seedfile" );
76
77 if( ret == MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR )
78 {
79 mbedtls_printf( "Failed to open seedfile. Generating one.\n" );
80 ret = mbedtls_ctr_drbg_write_seed_file( &ctr_drbg, "seedfile" );
81 if( ret != 0 )
82 {
83 mbedtls_printf( "failed in mbedtls_ctr_drbg_write_seed_file: %d\n", ret );
84 goto cleanup;
85 }
86 }
87 else if( ret != 0 )
88 {
89 mbedtls_printf( "failed in mbedtls_ctr_drbg_update_seed_file: %d\n", ret );
90 goto cleanup;
91 }
92 #endif
93
94 for( i = 0, k = 768; i < k; i++ )
95 {
96 ret = mbedtls_ctr_drbg_random( &ctr_drbg, buf, sizeof( buf ) );
97 if( ret != 0 )
98 {
99 mbedtls_printf("failed!\n");
100 goto cleanup;
101 }
102
103 fwrite( buf, 1, sizeof( buf ), f );
104
105 mbedtls_printf( "Generating %ldkb of data in file '%s'... %04.1f" \
106 "%% done\r", (long)(sizeof(buf) * k / 1024), argv[1], (100 * (float) (i + 1)) / k );
107 fflush( stdout );
108 }
109
110 exit_code = MBEDTLS_EXIT_SUCCESS;
111
112 cleanup:
113 mbedtls_printf("\n");
114
115 fclose( f );
116 mbedtls_ctr_drbg_free( &ctr_drbg );
117 mbedtls_entropy_free( &entropy );
118
119 mbedtls_exit( exit_code );
120 }
121 #endif /* MBEDTLS_CTR_DRBG_C && MBEDTLS_ENTROPY_C */
122