Mbed TLS v2.28.5
entropy.h
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1 
6 /*
7  * Copyright The Mbed TLS Contributors
8  * SPDX-License-Identifier: Apache-2.0
9  *
10  * Licensed under the Apache License, Version 2.0 (the "License"); you may
11  * not use this file except in compliance with the License.
12  * You may obtain a copy of the License at
13  *
14  * http://www.apache.org/licenses/LICENSE-2.0
15  *
16  * Unless required by applicable law or agreed to in writing, software
17  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
18  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
19  * See the License for the specific language governing permissions and
20  * limitations under the License.
21  */
22 #ifndef MBEDTLS_ENTROPY_H
23 #define MBEDTLS_ENTROPY_H
24 
25 #if !defined(MBEDTLS_CONFIG_FILE)
26 #include "mbedtls/config.h"
27 #else
28 #include MBEDTLS_CONFIG_FILE
29 #endif
30 
31 #include <stddef.h>
32 
33 #if defined(MBEDTLS_SHA512_C) && !defined(MBEDTLS_ENTROPY_FORCE_SHA256)
34 #include "mbedtls/sha512.h"
35 #define MBEDTLS_ENTROPY_SHA512_ACCUMULATOR
36 #else
37 #if defined(MBEDTLS_SHA256_C)
38 #define MBEDTLS_ENTROPY_SHA256_ACCUMULATOR
39 #include "mbedtls/sha256.h"
40 #endif
41 #endif
42 
43 #if defined(MBEDTLS_THREADING_C)
44 #include "mbedtls/threading.h"
45 #endif
46 
47 #if defined(MBEDTLS_HAVEGE_C)
48 #include "mbedtls/havege.h"
49 #endif
50 
52 #define MBEDTLS_ERR_ENTROPY_SOURCE_FAILED -0x003C
53 
54 #define MBEDTLS_ERR_ENTROPY_MAX_SOURCES -0x003E
55 
56 #define MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED -0x0040
57 
58 #define MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE -0x003D
59 
60 #define MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR -0x003F
61 
70 #if !defined(MBEDTLS_ENTROPY_MAX_SOURCES)
71 #define MBEDTLS_ENTROPY_MAX_SOURCES 20
72 #endif
73 
74 #if !defined(MBEDTLS_ENTROPY_MAX_GATHER)
75 #define MBEDTLS_ENTROPY_MAX_GATHER 128
76 #endif
77 
80 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
81 #define MBEDTLS_ENTROPY_BLOCK_SIZE 64
82 #else
83 #define MBEDTLS_ENTROPY_BLOCK_SIZE 32
84 #endif
85 
86 #define MBEDTLS_ENTROPY_MAX_SEED_SIZE 1024
87 #define MBEDTLS_ENTROPY_SOURCE_MANUAL MBEDTLS_ENTROPY_MAX_SOURCES
88 
89 #define MBEDTLS_ENTROPY_SOURCE_STRONG 1
90 #define MBEDTLS_ENTROPY_SOURCE_WEAK 0
92 #ifdef __cplusplus
93 extern "C" {
94 #endif
95 
107 typedef int (*mbedtls_entropy_f_source_ptr)(void *data, unsigned char *output, size_t len,
108  size_t *olen);
109 
115  void *p_source;
116  size_t size;
117  size_t threshold;
118  int strong;
119 }
121 
125 typedef struct mbedtls_entropy_context {
126  int accumulator_started; /* 0 after init.
127  * 1 after the first update.
128  * -1 after free. */
129 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
131 #elif defined(MBEDTLS_ENTROPY_SHA256_ACCUMULATOR)
133 #endif
134  int source_count; /* Number of entries used in source. */
136 #if defined(MBEDTLS_HAVEGE_C)
138 #endif
139 #if defined(MBEDTLS_THREADING_C)
141 #endif
142 #if defined(MBEDTLS_ENTROPY_NV_SEED)
143  int initial_entropy_run;
144 #endif
145 }
147 
154 
161 
180  mbedtls_entropy_f_source_ptr f_source, void *p_source,
181  size_t threshold, int strong);
182 
192 
204 int mbedtls_entropy_func(void *data, unsigned char *output, size_t len);
205 
217  const unsigned char *data, size_t len);
218 
219 #if defined(MBEDTLS_ENTROPY_NV_SEED)
220 
228 int mbedtls_entropy_update_nv_seed(mbedtls_entropy_context *ctx);
229 #endif /* MBEDTLS_ENTROPY_NV_SEED */
230 
231 #if defined(MBEDTLS_FS_IO)
232 
242 int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path);
243 
257 #endif /* MBEDTLS_FS_IO */
258 
259 #if defined(MBEDTLS_SELF_TEST)
260 
268 int mbedtls_entropy_self_test(int verbose);
269 
270 #if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
271 
284 int mbedtls_entropy_source_self_test(int verbose);
285 #endif /* MBEDTLS_ENTROPY_HARDWARE_ALT */
286 #endif /* MBEDTLS_SELF_TEST */
287 
288 #ifdef __cplusplus
289 }
290 #endif
291 
292 #endif /* entropy.h */
mbedtls_entropy_source_state source[MBEDTLS_ENTROPY_MAX_SOURCES]
Definition: entropy.h:135
mbedtls_havege_state havege_data
Definition: entropy.h:137
HAVEGE state structure.
Definition: havege.h:43
mbedtls_entropy_f_source_ptr f_source
Definition: entropy.h:114
#define MBEDTLS_ENTROPY_MAX_SOURCES
Definition: entropy.h:71
Configuration options (set of defines)
mbedtls_threading_mutex_t mutex
Definition: entropy.h:140
void mbedtls_entropy_init(mbedtls_entropy_context *ctx)
Initialize the context.
Entropy context structure.
Definition: entropy.h:125
int mbedtls_entropy_self_test(int verbose)
Checkup routine.
mbedtls_sha512_context accumulator
Definition: entropy.h:130
int mbedtls_entropy_func(void *data, unsigned char *output, size_t len)
Retrieve entropy from the accumulator (Maximum length: MBEDTLS_ENTROPY_BLOCK_SIZE) (Thread-safe if MB...
struct mbedtls_entropy_source_state mbedtls_entropy_source_state
Entropy source state.
Threading abstraction layer.
The SHA-512 context structure.
Definition: sha512.h:57
HAVEGE: HArdware Volatile Entropy Gathering and Expansion.
The SHA-256 context structure.
Definition: sha256.h:58
void mbedtls_entropy_free(mbedtls_entropy_context *ctx)
Free the data in the context.
int mbedtls_entropy_update_manual(mbedtls_entropy_context *ctx, const unsigned char *data, size_t len)
Add data to the accumulator manually (Thread-safe if MBEDTLS_THREADING_C is enabled) ...
int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path)
Write a seed file.
This file contains SHA-384 and SHA-512 definitions and functions.
struct mbedtls_entropy_context mbedtls_entropy_context
Entropy context structure.
int mbedtls_entropy_gather(mbedtls_entropy_context *ctx)
Trigger an extra gather poll for the accumulator (Thread-safe if MBEDTLS_THREADING_C is enabled) ...
int mbedtls_entropy_update_seed_file(mbedtls_entropy_context *ctx, const char *path)
Read and update a seed file. Seed is added to this instance. No more than MBEDTLS_ENTROPY_MAX_SEED_SI...
int(* mbedtls_entropy_f_source_ptr)(void *data, unsigned char *output, size_t len, size_t *olen)
Entropy poll callback pointer.
Definition: entropy.h:107
This file contains SHA-224 and SHA-256 definitions and functions.
Entropy source state.
Definition: entropy.h:113
int mbedtls_entropy_add_source(mbedtls_entropy_context *ctx, mbedtls_entropy_f_source_ptr f_source, void *p_source, size_t threshold, int strong)
Adds an entropy source to poll (Thread-safe if MBEDTLS_THREADING_C is enabled)