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
11 *
12 * Licensed under the Apache License, Version 2.0 (the "License"); you may
13 * not use this file except in compliance with the License.
14 * You may obtain a copy of the License at
15 *
16 * http://www.apache.org/licenses/LICENSE-2.0
17 *
18 * Unless required by applicable law or agreed to in writing, software
19 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
20 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
21 * See the License for the specific language governing permissions and
22 * limitations under the License.
23 */
24
25 /*
26 * for arc4random_buf() from <stdlib.h>
27 */
28 #if defined(__NetBSD__)
29 #define _NETBSD_SOURCE 1
30 #elif defined(__OpenBSD__)
31 #define _BSD_SOURCE 1
32 #endif
33
34 #include <test/macros.h>
35 #include <test/random.h>
36 #include <string.h>
37
mbedtls_test_rnd_std_rand(void * rng_state,unsigned char * output,size_t len)38 int mbedtls_test_rnd_std_rand( void *rng_state,
39 unsigned char *output,
40 size_t len )
41 {
42 #if !defined(__OpenBSD__) && !defined(__NetBSD__)
43 size_t i;
44
45 if( rng_state != NULL )
46 rng_state = NULL;
47
48 for( i = 0; i < len; ++i )
49 output[i] = rand();
50 #else
51 if( rng_state != NULL )
52 rng_state = NULL;
53
54 arc4random_buf( output, len );
55 #endif /* !OpenBSD && !NetBSD */
56
57 return( 0 );
58 }
59
mbedtls_test_rnd_zero_rand(void * rng_state,unsigned char * output,size_t len)60 int mbedtls_test_rnd_zero_rand( void *rng_state,
61 unsigned char *output,
62 size_t len )
63 {
64 if( rng_state != NULL )
65 rng_state = NULL;
66
67 memset( output, 0, len );
68
69 return( 0 );
70 }
71
mbedtls_test_rnd_buffer_rand(void * rng_state,unsigned char * output,size_t len)72 int mbedtls_test_rnd_buffer_rand( void *rng_state,
73 unsigned char *output,
74 size_t len )
75 {
76 mbedtls_test_rnd_buf_info *info = (mbedtls_test_rnd_buf_info *) rng_state;
77 size_t use_len;
78
79 if( rng_state == NULL )
80 return( mbedtls_test_rnd_std_rand( NULL, output, len ) );
81
82 use_len = len;
83 if( len > info->length )
84 use_len = info->length;
85
86 if( use_len )
87 {
88 memcpy( output, info->buf, use_len );
89 info->buf += use_len;
90 info->length -= use_len;
91 }
92
93 if( len - use_len > 0 )
94 return( mbedtls_test_rnd_std_rand( NULL, output + use_len,
95 len - use_len ) );
96
97 return( 0 );
98 }
99
mbedtls_test_rnd_pseudo_rand(void * rng_state,unsigned char * output,size_t len)100 int mbedtls_test_rnd_pseudo_rand( void *rng_state,
101 unsigned char *output,
102 size_t len )
103 {
104 mbedtls_test_rnd_pseudo_info *info =
105 (mbedtls_test_rnd_pseudo_info *) rng_state;
106 uint32_t i, *k, sum, delta=0x9E3779B9;
107 unsigned char result[4], *out = output;
108
109 if( rng_state == NULL )
110 return( mbedtls_test_rnd_std_rand( NULL, output, len ) );
111
112 k = info->key;
113
114 while( len > 0 )
115 {
116 size_t use_len = ( len > 4 ) ? 4 : len;
117 sum = 0;
118
119 for( i = 0; i < 32; i++ )
120 {
121 info->v0 += ( ( ( info->v1 << 4 ) ^ ( info->v1 >> 5 ) )
122 + info->v1 ) ^ ( sum + k[sum & 3] );
123 sum += delta;
124 info->v1 += ( ( ( info->v0 << 4 ) ^ ( info->v0 >> 5 ) )
125 + info->v0 ) ^ ( sum + k[( sum>>11 ) & 3] );
126 }
127
128 PUT_UINT32_BE( info->v0, result, 0 );
129 memcpy( out, result, use_len );
130 len -= use_len;
131 out += 4;
132 }
133
134 return( 0 );
135 }
136
