d56742e5330132264c33c906c1e74f9a99c4a39f
[openssl.git] / include / internal / rand.h
1 /*
2  * Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL license (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9
10 #ifndef HEADER_DRBG_RAND_H
11 # define HEADER_DRBG_RAND_H
12
13 /* In CTR mode, disable derivation function ctr_df */
14 #define RAND_DRBG_FLAG_CTR_NO_DF            0x1
15
16 /*
17  * Default security strength (in the sense of [NIST SP 800-90Ar1])
18  * of the default OpenSSL DRBG, and the corresponding NID.
19  *
20  * Currently supported values: 128, 192, 256
21  *
22  * TODO(DRBG): would be nice to have the strength configurable
23  */
24 # define RAND_DRBG_STRENGTH             128
25 # define RAND_DRBG_NID                  NID_aes_128_ctr
26
27 /*
28  * Object lifetime functions.
29  */
30 RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent);
31 RAND_DRBG *RAND_DRBG_secure_new(int type, unsigned int flags, RAND_DRBG *parent);
32 int RAND_DRBG_set(RAND_DRBG *drbg, int type, unsigned int flags);
33 int RAND_DRBG_instantiate(RAND_DRBG *drbg,
34                           const unsigned char *pers, size_t perslen);
35 int RAND_DRBG_uninstantiate(RAND_DRBG *drbg);
36 void RAND_DRBG_free(RAND_DRBG *drbg);
37
38 /*
39  * Object "use" functions.
40  */
41 int RAND_DRBG_reseed(RAND_DRBG *drbg,
42                      const unsigned char *adin, size_t adinlen);
43 int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen,
44                        int prediction_resistance,
45                        const unsigned char *adin, size_t adinlen);
46 int RAND_DRBG_bytes(RAND_DRBG *drbg, unsigned char *out, size_t outlen);
47
48 int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, unsigned int interval);
49 int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval);
50
51 RAND_DRBG *RAND_DRBG_get0_master(void);
52 RAND_DRBG *RAND_DRBG_get0_public(void);
53 RAND_DRBG *RAND_DRBG_get0_private(void);
54
55 /*
56  * EXDATA
57  */
58 #define RAND_DRBG_get_ex_new_index(l, p, newf, dupf, freef) \
59     CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DRBG, l, p, newf, dupf, freef)
60 int RAND_DRBG_set_ex_data(RAND_DRBG *dctx, int idx, void *arg);
61 void *RAND_DRBG_get_ex_data(const RAND_DRBG *dctx, int idx);
62
63 /*
64  * Callback functions.  See comments in drbg_lib.c
65  */
66 typedef size_t (*RAND_DRBG_get_entropy_fn)(RAND_DRBG *ctx,
67                                            unsigned char **pout,
68                                            int entropy, size_t min_len,
69                                            size_t max_len);
70 typedef void (*RAND_DRBG_cleanup_entropy_fn)(RAND_DRBG *ctx,
71                                              unsigned char *out, size_t outlen);
72 typedef size_t (*RAND_DRBG_get_nonce_fn)(RAND_DRBG *ctx, unsigned char **pout,
73                                          int entropy, size_t min_len,
74                                          size_t max_len);
75 typedef void (*RAND_DRBG_cleanup_nonce_fn)(RAND_DRBG *ctx,
76                                            unsigned char *out, size_t outlen);
77
78 int RAND_DRBG_set_callbacks(RAND_DRBG *dctx,
79                             RAND_DRBG_get_entropy_fn get_entropy,
80                             RAND_DRBG_cleanup_entropy_fn cleanup_entropy,
81                             RAND_DRBG_get_nonce_fn get_nonce,
82                             RAND_DRBG_cleanup_nonce_fn cleanup_nonce);
83
84 /*
85  * RAND_POOL functions
86  */
87 RAND_POOL *RAND_POOL_new(int entropy_requested, size_t min_len, size_t max_len);
88 void RAND_POOL_free(RAND_POOL *pool);
89
90 const unsigned char *RAND_POOL_buffer(RAND_POOL *pool);
91 unsigned char *RAND_POOL_detach(RAND_POOL *pool);
92
93 size_t RAND_POOL_entropy(RAND_POOL *pool);
94 size_t RAND_POOL_length(RAND_POOL *pool);
95
96 size_t RAND_POOL_entropy_available(RAND_POOL *pool);
97 size_t RAND_POOL_entropy_needed(RAND_POOL *pool);
98 size_t RAND_POOL_bytes_needed(RAND_POOL *pool, unsigned int entropy_per_byte);
99 size_t RAND_POOL_bytes_remaining(RAND_POOL *pool);
100
101 size_t RAND_POOL_add(RAND_POOL *pool,
102                      const unsigned char *buffer, size_t len, size_t entropy);
103 unsigned char *RAND_POOL_add_begin(RAND_POOL *pool, size_t len);
104 size_t RAND_POOL_add_end(RAND_POOL *pool, size_t len, size_t entropy);
105
106
107 /*
108  * Add random bytes to the pool to acquire requested amount of entropy
109  *
110  * This function is platform specific and tries to acquire the requested
111  * amount of entropy by polling platform specific entropy sources.
112  *
113  * If the function succeeds in acquiring at least |entropy_requested| bits
114  * of entropy, the total entropy count is returned. If it fails, it returns
115  * an entropy count of 0.
116  */
117 size_t RAND_POOL_acquire_entropy(RAND_POOL *pool);
118 #endif