Minos Galanakis | 2c824b4 | 2025-03-20 09:28:45 +0000 | [diff] [blame^] | 1 | /** |
| 2 | * \file random.c |
| 3 | * |
| 4 | * \brief This file contains the helper functions to generate random numbers |
| 5 | * for the purpose of testing. |
| 6 | */ |
| 7 | |
| 8 | /* |
| 9 | * Copyright The Mbed TLS Contributors |
| 10 | * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later |
| 11 | */ |
| 12 | |
| 13 | /* |
| 14 | * for arc4random_buf() from <stdlib.h> |
| 15 | */ |
| 16 | #if defined(__NetBSD__) |
| 17 | #define _NETBSD_SOURCE 1 |
| 18 | #elif defined(__OpenBSD__) |
| 19 | #define _BSD_SOURCE 1 |
| 20 | #endif |
| 21 | |
| 22 | #include <test/macros.h> |
| 23 | #include <test/random.h> |
| 24 | #include <string.h> |
| 25 | |
| 26 | #include <mbedtls/entropy.h> |
| 27 | #include <alignment.h> |
| 28 | |
| 29 | int mbedtls_test_rnd_std_rand(void *rng_state, |
| 30 | unsigned char *output, |
| 31 | size_t len) |
| 32 | { |
| 33 | #if !defined(__OpenBSD__) && !defined(__NetBSD__) |
| 34 | size_t i; |
| 35 | |
| 36 | if (rng_state != NULL) { |
| 37 | rng_state = NULL; |
| 38 | } |
| 39 | |
| 40 | for (i = 0; i < len; ++i) { |
| 41 | output[i] = rand(); |
| 42 | } |
| 43 | #else |
| 44 | if (rng_state != NULL) { |
| 45 | rng_state = NULL; |
| 46 | } |
| 47 | |
| 48 | arc4random_buf(output, len); |
| 49 | #endif /* !OpenBSD && !NetBSD */ |
| 50 | |
| 51 | return 0; |
| 52 | } |
| 53 | |
| 54 | int mbedtls_test_rnd_zero_rand(void *rng_state, |
| 55 | unsigned char *output, |
| 56 | size_t len) |
| 57 | { |
| 58 | if (rng_state != NULL) { |
| 59 | rng_state = NULL; |
| 60 | } |
| 61 | |
| 62 | memset(output, 0, len); |
| 63 | |
| 64 | return 0; |
| 65 | } |
| 66 | |
| 67 | int mbedtls_test_rnd_buffer_rand(void *rng_state, |
| 68 | unsigned char *output, |
| 69 | size_t len) |
| 70 | { |
| 71 | mbedtls_test_rnd_buf_info *info = (mbedtls_test_rnd_buf_info *) rng_state; |
| 72 | size_t use_len; |
| 73 | |
| 74 | if (rng_state == NULL) { |
| 75 | return mbedtls_test_rnd_std_rand(NULL, output, len); |
| 76 | } |
| 77 | |
| 78 | use_len = len; |
| 79 | if (len > info->length) { |
| 80 | use_len = info->length; |
| 81 | } |
| 82 | |
| 83 | if (use_len) { |
| 84 | memcpy(output, info->buf, use_len); |
| 85 | info->buf += use_len; |
| 86 | info->length -= use_len; |
| 87 | } |
| 88 | |
| 89 | if (len - use_len > 0) { |
| 90 | if (info->fallback_f_rng != NULL) { |
| 91 | return info->fallback_f_rng(info->fallback_p_rng, |
| 92 | output + use_len, |
| 93 | len - use_len); |
| 94 | } else { |
| 95 | return MBEDTLS_ERR_ENTROPY_SOURCE_FAILED; |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | int mbedtls_test_rnd_pseudo_rand(void *rng_state, |
| 103 | unsigned char *output, |
| 104 | size_t len) |
| 105 | { |
| 106 | mbedtls_test_rnd_pseudo_info *info = |
| 107 | (mbedtls_test_rnd_pseudo_info *) rng_state; |
| 108 | uint32_t i, *k, sum, delta = 0x9E3779B9; |
| 109 | unsigned char result[4], *out = output; |
| 110 | |
| 111 | if (rng_state == NULL) { |
| 112 | return mbedtls_test_rnd_std_rand(NULL, output, len); |
| 113 | } |
| 114 | |
| 115 | k = info->key; |
| 116 | |
| 117 | while (len > 0) { |
| 118 | size_t use_len = (len > 4) ? 4 : len; |
| 119 | sum = 0; |
| 120 | |
| 121 | for (i = 0; i < 32; i++) { |
| 122 | info->v0 += (((info->v1 << 4) ^ (info->v1 >> 5)) |
| 123 | + info->v1) ^ (sum + k[sum & 3]); |
| 124 | sum += delta; |
| 125 | info->v1 += (((info->v0 << 4) ^ (info->v0 >> 5)) |
| 126 | + info->v0) ^ (sum + k[(sum>>11) & 3]); |
| 127 | } |
| 128 | |
| 129 | MBEDTLS_PUT_UINT32_BE(info->v0, result, 0); |
| 130 | memcpy(out, result, use_len); |
| 131 | len -= use_len; |
| 132 | out += 4; |
| 133 | } |
| 134 | |
| 135 | return 0; |
| 136 | } |