1/**
2 *  \brief Use and generate multiple entropies calls into a file
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_ENTROPY_C) && defined(MBEDTLS_FS_IO)
25#include "mbedtls/entropy.h"
26
27#include <stdio.h>
28#endif
29
30#if !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_FS_IO)
31int main(void)
32{
33    mbedtls_printf("MBEDTLS_ENTROPY_C and/or MBEDTLS_FS_IO not defined.\n");
34    mbedtls_exit(0);
35}
36#else
37
38
39int main(int argc, char *argv[])
40{
41    FILE *f;
42    int i, k, ret = 1;
43    int exit_code = MBEDTLS_EXIT_FAILURE;
44    mbedtls_entropy_context entropy;
45    unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE];
46
47    if (argc < 2) {
48        mbedtls_fprintf(stderr, "usage: %s <output filename>\n", argv[0]);
49        mbedtls_exit(exit_code);
50    }
51
52    if ((f = fopen(argv[1], "wb+")) == NULL) {
53        mbedtls_printf("failed to open '%s' for writing.\n", argv[1]);
54        mbedtls_exit(exit_code);
55    }
56
57    mbedtls_entropy_init(&entropy);
58
59    for (i = 0, k = 768; i < k; i++) {
60        ret = mbedtls_entropy_func(&entropy, buf, sizeof(buf));
61        if (ret != 0) {
62            mbedtls_printf("  failed\n  !  mbedtls_entropy_func returned -%04X\n",
63                           (unsigned int) ret);
64            goto cleanup;
65        }
66
67        fwrite(buf, 1, sizeof(buf), f);
68
69        mbedtls_printf("Generating %ldkb of data in file '%s'... %04.1f" \
70                       "%% done\r",
71                       (long) (sizeof(buf) * k / 1024),
72                       argv[1],
73                       (100 * (float) (i + 1)) / k);
74        fflush(stdout);
75    }
76
77    exit_code = MBEDTLS_EXIT_SUCCESS;
78
79cleanup:
80    mbedtls_printf("\n");
81
82    fclose(f);
83    mbedtls_entropy_free(&entropy);
84
85    mbedtls_exit(exit_code);
86}
87#endif /* MBEDTLS_ENTROPY_C */
88