Mbed TLS v2.28.8
entropy.h
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1 
6 /*
7  * Copyright The Mbed TLS Contributors
8  * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
9  */
10 #ifndef MBEDTLS_ENTROPY_H
11 #define MBEDTLS_ENTROPY_H
12 
13 #if !defined(MBEDTLS_CONFIG_FILE)
14 #include "mbedtls/config.h"
15 #else
16 #include MBEDTLS_CONFIG_FILE
17 #endif
18 
19 #include <stddef.h>
20 
21 #if defined(MBEDTLS_SHA512_C) && !defined(MBEDTLS_ENTROPY_FORCE_SHA256)
22 #include "mbedtls/sha512.h"
23 #define MBEDTLS_ENTROPY_SHA512_ACCUMULATOR
24 #else
25 #if defined(MBEDTLS_SHA256_C)
26 #define MBEDTLS_ENTROPY_SHA256_ACCUMULATOR
27 #include "mbedtls/sha256.h"
28 #endif
29 #endif
30 
31 #if defined(MBEDTLS_THREADING_C)
32 #include "mbedtls/threading.h"
33 #endif
34 
35 #if defined(MBEDTLS_HAVEGE_C)
36 #include "mbedtls/havege.h"
37 #endif
38 
40 #define MBEDTLS_ERR_ENTROPY_SOURCE_FAILED -0x003C
41 
42 #define MBEDTLS_ERR_ENTROPY_MAX_SOURCES -0x003E
43 
44 #define MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED -0x0040
45 
46 #define MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE -0x003D
47 
48 #define MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR -0x003F
49 
58 #if !defined(MBEDTLS_ENTROPY_MAX_SOURCES)
59 #define MBEDTLS_ENTROPY_MAX_SOURCES 20
60 #endif
61 
62 #if !defined(MBEDTLS_ENTROPY_MAX_GATHER)
63 #define MBEDTLS_ENTROPY_MAX_GATHER 128
64 #endif
65 
68 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
69 #define MBEDTLS_ENTROPY_BLOCK_SIZE 64
70 #else
71 #define MBEDTLS_ENTROPY_BLOCK_SIZE 32
72 #endif
73 
74 #define MBEDTLS_ENTROPY_MAX_SEED_SIZE 1024
75 #define MBEDTLS_ENTROPY_SOURCE_MANUAL MBEDTLS_ENTROPY_MAX_SOURCES
76 
77 #define MBEDTLS_ENTROPY_SOURCE_STRONG 1
78 #define MBEDTLS_ENTROPY_SOURCE_WEAK 0
80 #ifdef __cplusplus
81 extern "C" {
82 #endif
83 
95 typedef int (*mbedtls_entropy_f_source_ptr)(void *data, unsigned char *output, size_t len,
96  size_t *olen);
97 
103  void *p_source;
104  size_t size;
105  size_t threshold;
106  int strong;
107 }
109 
113 typedef struct mbedtls_entropy_context {
114  int accumulator_started; /* 0 after init.
115  * 1 after the first update.
116  * -1 after free. */
117 #if defined(MBEDTLS_ENTROPY_SHA512_ACCUMULATOR)
119 #elif defined(MBEDTLS_ENTROPY_SHA256_ACCUMULATOR)
121 #endif
122  int source_count; /* Number of entries used in source. */
124 #if defined(MBEDTLS_HAVEGE_C)
126 #endif
127 #if defined(MBEDTLS_THREADING_C)
129 #endif
130 #if defined(MBEDTLS_ENTROPY_NV_SEED)
131  int initial_entropy_run;
132 #endif
133 }
135 
142 
149 
168  mbedtls_entropy_f_source_ptr f_source, void *p_source,
169  size_t threshold, int strong);
170 
180 
192 int mbedtls_entropy_func(void *data, unsigned char *output, size_t len);
193 
205  const unsigned char *data, size_t len);
206 
207 #if defined(MBEDTLS_ENTROPY_NV_SEED)
208 
216 int mbedtls_entropy_update_nv_seed(mbedtls_entropy_context *ctx);
217 #endif /* MBEDTLS_ENTROPY_NV_SEED */
218 
219 #if defined(MBEDTLS_FS_IO)
220 
230 int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path);
231 
245 #endif /* MBEDTLS_FS_IO */
246 
247 #if defined(MBEDTLS_SELF_TEST)
248 
256 int mbedtls_entropy_self_test(int verbose);
257 
258 #if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)
259 
272 int mbedtls_entropy_source_self_test(int verbose);
273 #endif /* MBEDTLS_ENTROPY_HARDWARE_ALT */
274 #endif /* MBEDTLS_SELF_TEST */
275 
276 #ifdef __cplusplus
277 }
278 #endif
279 
280 #endif /* entropy.h */
mbedtls_entropy_f_source_ptr
int(* mbedtls_entropy_f_source_ptr)(void *data, unsigned char *output, size_t len, size_t *olen)
Entropy poll callback pointer.
Definition: entropy.h:95
mbedtls_entropy_source_state::strong
int strong
Definition: entropy.h:106
mbedtls_entropy_context::mutex
mbedtls_threading_mutex_t mutex
Definition: entropy.h:128
MBEDTLS_ENTROPY_MAX_SOURCES
#define MBEDTLS_ENTROPY_MAX_SOURCES
Definition: entropy.h:59
sha512.h
This file contains SHA-384 and SHA-512 definitions and functions.
mbedtls_threading_mutex_t
Definition: threading.h:37
mbedtls_entropy_init
void mbedtls_entropy_init(mbedtls_entropy_context *ctx)
Initialize the context.
mbedtls_entropy_context::source
mbedtls_entropy_source_state source[MBEDTLS_ENTROPY_MAX_SOURCES]
Definition: entropy.h:123
mbedtls_havege_state
HAVEGE state structure.
Definition: havege.h:31
mbedtls_entropy_context
Entropy context structure.
Definition: entropy.h:113
havege.h
HAVEGE: HArdware Volatile Entropy Gathering and Expansion.
mbedtls_entropy_source_state::threshold
size_t threshold
Definition: entropy.h:105
mbedtls_entropy_source_state::size
size_t size
Definition: entropy.h:104
mbedtls_entropy_self_test
int mbedtls_entropy_self_test(int verbose)
Checkup routine.
mbedtls_sha512_context
The SHA-512 context structure.
Definition: sha512.h:45
mbedtls_entropy_source_state
Entropy source state.
Definition: entropy.h:101
mbedtls_entropy_func
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...
mbedtls_entropy_context::accumulator
mbedtls_sha512_context accumulator
Definition: entropy.h:118
sha256.h
This file contains SHA-224 and SHA-256 definitions and functions.
mbedtls_entropy_source_state
struct mbedtls_entropy_source_state mbedtls_entropy_source_state
Entropy source state.
mbedtls_entropy_free
void mbedtls_entropy_free(mbedtls_entropy_context *ctx)
Free the data in the context.
threading.h
Threading abstraction layer.
mbedtls_entropy_write_seed_file
int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path)
Write a seed file.
mbedtls_entropy_context
struct mbedtls_entropy_context mbedtls_entropy_context
Entropy context structure.
mbedtls_sha256_context
The SHA-256 context structure.
Definition: sha256.h:46
mbedtls_entropy_context::accumulator_started
int accumulator_started
Definition: entropy.h:114
mbedtls_entropy_source_state::p_source
void * p_source
Definition: entropy.h:103
mbedtls_entropy_update_manual
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)
config.h
Configuration options (set of defines)
mbedtls_entropy_context::source_count
int source_count
Definition: entropy.h:122
mbedtls_entropy_context::havege_data
mbedtls_havege_state havege_data
Definition: entropy.h:125
mbedtls_entropy_source_state::f_source
mbedtls_entropy_f_source_ptr f_source
Definition: entropy.h:102
mbedtls_entropy_gather
int mbedtls_entropy_gather(mbedtls_entropy_context *ctx)
Trigger an extra gather poll for the accumulator (Thread-safe if MBEDTLS_THREADING_C is enabled)
mbedtls_entropy_update_seed_file
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...
mbedtls_entropy_add_source
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)