DRBG: make the derivation function the default for ctr_drbg
[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 int RAND_DRBG_lock(RAND_DRBG *drbg);
52 int RAND_DRBG_unlock(RAND_DRBG *drbg);
53 int RAND_DRBG_enable_locking(RAND_DRBG *drbg);
54
55 RAND_DRBG *RAND_DRBG_get0_master(void);
56 RAND_DRBG *RAND_DRBG_get0_public(void);
57 RAND_DRBG *RAND_DRBG_get0_private(void);
58
59 /*
60  * EXDATA
61  */
62 #define RAND_DRBG_get_ex_new_index(l, p, newf, dupf, freef) \
63     CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DRBG, l, p, newf, dupf, freef)
64 int RAND_DRBG_set_ex_data(RAND_DRBG *dctx, int idx, void *arg);
65 void *RAND_DRBG_get_ex_data(const RAND_DRBG *dctx, int idx);
66
67 /*
68  * Callback functions.  See comments in drbg_lib.c
69  */
70 typedef size_t (*RAND_DRBG_get_entropy_fn)(RAND_DRBG *ctx,
71                                            unsigned char **pout,
72                                            int entropy, size_t min_len,
73                                            size_t max_len);
74 typedef void (*RAND_DRBG_cleanup_entropy_fn)(RAND_DRBG *ctx,
75                                              unsigned char *out, size_t outlen);
76 typedef size_t (*RAND_DRBG_get_nonce_fn)(RAND_DRBG *ctx, unsigned char **pout,
77                                          int entropy, size_t min_len,
78                                          size_t max_len);
79 typedef void (*RAND_DRBG_cleanup_nonce_fn)(RAND_DRBG *ctx,
80                                            unsigned char *out, size_t outlen);
81
82 int RAND_DRBG_set_callbacks(RAND_DRBG *dctx,
83                             RAND_DRBG_get_entropy_fn get_entropy,
84                             RAND_DRBG_cleanup_entropy_fn cleanup_entropy,
85                             RAND_DRBG_get_nonce_fn get_nonce,
86                             RAND_DRBG_cleanup_nonce_fn cleanup_nonce);
87
88 /*
89  * RAND_POOL functions
90  */
91 RAND_POOL *RAND_POOL_new(int entropy_requested, size_t min_len, size_t max_len);
92 void RAND_POOL_free(RAND_POOL *pool);
93
94 const unsigned char *RAND_POOL_buffer(RAND_POOL *pool);
95 unsigned char *RAND_POOL_detach(RAND_POOL *pool);
96
97 size_t RAND_POOL_entropy(RAND_POOL *pool);
98 size_t RAND_POOL_length(RAND_POOL *pool);
99
100 size_t RAND_POOL_entropy_available(RAND_POOL *pool);
101 size_t RAND_POOL_entropy_needed(RAND_POOL *pool);
102 size_t RAND_POOL_bytes_needed(RAND_POOL *pool, unsigned int entropy_per_byte);
103 size_t RAND_POOL_bytes_remaining(RAND_POOL *pool);
104
105 size_t RAND_POOL_add(RAND_POOL *pool,
106                      const unsigned char *buffer, size_t len, size_t entropy);
107 unsigned char *RAND_POOL_add_begin(RAND_POOL *pool, size_t len);
108 size_t RAND_POOL_add_end(RAND_POOL *pool, size_t len, size_t entropy);
109
110
111 /*
112  * Add random bytes to the pool to acquire requested amount of entropy
113  *
114  * This function is platform specific and tries to acquire the requested
115  * amount of entropy by polling platform specific entropy sources.
116  *
117  * If the function succeeds in acquiring at least |entropy_requested| bits
118  * of entropy, the total entropy count is returned. If it fails, it returns
119  * an entropy count of 0.
120  */
121 size_t RAND_POOL_acquire_entropy(RAND_POOL *pool);
122 #endif