2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (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
10 #ifndef OSSL_CRYPTO_PROV_LOCAL_H
11 # define OSSL_CRYPTO_PROV_LOCAL_H
13 # include <openssl/evp.h>
14 # include <openssl/core_dispatch.h>
15 # include <openssl/core_names.h>
16 # include <openssl/params.h>
17 # include "internal/tsan_assist.h"
18 # include "internal/nelem.h"
19 # include "internal/numbers.h"
20 # include "prov/provider_ctx.h"
22 /* How many times to read the TSC as a randomness source. */
23 # define TSC_READ_COUNT 4
25 /* Maximum reseed intervals */
26 # define MAX_RESEED_INTERVAL (1 << 24)
27 # define MAX_RESEED_TIME_INTERVAL (1 << 20) /* approx. 12 days */
29 /* Default reseed intervals */
30 # define RESEED_INTERVAL (1 << 8)
31 # define TIME_INTERVAL (60*60) /* 1 hour */
34 * The number of bytes that constitutes an atomic lump of entropy with respect
35 * to the FIPS 140-2 section 4.9.2 Conditional Tests. The size is somewhat
36 * arbitrary, the smaller the value, the less entropy is consumed on first
37 * read but the higher the probability of the test failing by accident.
39 * The value is in bytes.
41 #define CRNGT_BUFSIZ 16
44 * Maximum input size for the DRBG (entropy, nonce, personalization string)
46 * NIST SP800 90Ar1 allows a maximum of (1 << 35) bits i.e., (1 << 32) bytes.
48 * We lower it to 'only' INT32_MAX bytes, which is equivalent to 2 gigabytes.
50 # define DRBG_MAX_LENGTH INT32_MAX
52 /* The default nonce */
54 # define DRBG_DEFAULT_PERS_STRING { 0x4f, 0x70, 0x65, 0x6e, 0x53, 0x53, \
55 0x4c, 0x20, 0x4e, 0x49, 0x53, 0x54, 0x20, 0x53, 0x50, 0x20, 0x38, 0x30, \
56 0x30, 0x2d, 0x39, 0x30, 0x41, 0x20, 0x44, 0x52, 0x42, 0x47, 0x00};
58 # define DRBG_DEFAULT_PERS_STRING "OpenSSL NIST SP 800-90A DRBG"
61 typedef struct prov_drbg_st PROV_DRBG;
63 /* DRBG status values */
64 typedef enum drbg_status_e {
71 * The state of all types of DRBGs.
77 /* Virtual functions are cache here */
78 int (*instantiate)(PROV_DRBG *drbg,
79 const unsigned char *entropy, size_t entropylen,
80 const unsigned char *nonce, size_t noncelen,
81 const unsigned char *pers, size_t perslen);
82 int (*uninstantiate)(PROV_DRBG *ctx);
83 int (*reseed)(PROV_DRBG *drbg, const unsigned char *ent, size_t ent_len,
84 const unsigned char *adin, size_t adin_len);
85 int (*generate)(PROV_DRBG *, unsigned char *out, size_t outlen,
86 const unsigned char *adin, size_t adin_len);
88 /* Parent PROV_RAND and its dispatch table functions */
90 OSSL_FUNC_rand_enable_locking_fn *parent_enable_locking;
91 OSSL_FUNC_rand_lock_fn *parent_lock;
92 OSSL_FUNC_rand_unlock_fn *parent_unlock;
93 OSSL_FUNC_rand_get_ctx_params_fn *parent_get_ctx_params;
94 OSSL_FUNC_rand_nonce_fn *parent_nonce;
95 OSSL_FUNC_rand_get_seed_fn *parent_get_seed;
96 OSSL_FUNC_rand_clear_seed_fn *parent_clear_seed;
98 const OSSL_DISPATCH *parent_dispatch;
101 * Stores the return value of openssl_get_fork_id() as of when we last
102 * reseeded. The DRBG reseeds automatically whenever drbg->fork_id !=
103 * openssl_get_fork_id(). Used to provide fork-safety and reseed this
104 * DRBG in the child process.
107 unsigned short flags; /* various external flags */
110 * The following parameters are setup by the per-type "init" function.
112 * The supported types and their init functions are:
113 * (1) CTR_DRBG: drbg_ctr_init().
114 * (2) HMAC_DRBG: drbg_hmac_init().
115 * (3) HASH_DRBG: drbg_hash_init().
117 * The parameters are closely related to the ones described in
118 * section '10.2.1 CTR_DRBG' of [NIST SP 800-90Ar1], with one
119 * crucial difference: In the NIST standard, all counts are given
120 * in bits, whereas in OpenSSL entropy counts are given in bits
121 * and buffer lengths are given in bytes.
123 * Since this difference has lead to some confusion in the past,
124 * (see [GitHub Issue #2443], formerly [rt.openssl.org #4055])
125 * the 'len' suffix has been added to all buffer sizes for
129 unsigned int strength;
131 size_t min_entropylen, max_entropylen;
132 size_t min_noncelen, max_noncelen;
133 size_t max_perslen, max_adinlen;
136 * Counts the number of generate requests since the last reseed
137 * (Starts at 1). This value is the reseed_counter as defined in
140 unsigned int generate_counter;
142 * Maximum number of generate requests until a reseed is required.
143 * This value is ignored if it is zero.
145 unsigned int reseed_interval;
146 /* Stores the time when the last reseeding occurred */
149 * Specifies the maximum time interval (in seconds) between reseeds.
150 * This value is ignored if it is zero.
152 time_t reseed_time_interval;
154 * Counts the number of reseeds since instantiation.
155 * This value is ignored if it is zero.
157 * This counter is used only for seed propagation from the <master> DRBG
158 * to its two children, the <public> and <private> DRBG. This feature is
159 * very special and its sole purpose is to ensure that any randomness which
160 * is added by PROV_add() or PROV_seed() will have an immediate effect on
161 * the output of PROV_bytes() resp. PROV_priv_bytes().
163 TSAN_QUALIFIER unsigned int reseed_counter;
164 unsigned int reseed_next_counter;
165 unsigned int parent_reseed_counter;
170 /* DRBG specific data */
173 /* Entropy and nonce gathering callbacks */
175 OSSL_INOUT_CALLBACK *get_entropy_fn;
176 OSSL_CALLBACK *cleanup_entropy_fn;
177 OSSL_INOUT_CALLBACK *get_nonce_fn;
178 OSSL_CALLBACK *cleanup_nonce_fn;
181 PROV_DRBG *ossl_rand_drbg_new
182 (void *provctx, void *parent, const OSSL_DISPATCH *parent_dispatch,
183 int (*dnew)(PROV_DRBG *ctx),
184 int (*instantiate)(PROV_DRBG *drbg,
185 const unsigned char *entropy, size_t entropylen,
186 const unsigned char *nonce, size_t noncelen,
187 const unsigned char *pers, size_t perslen),
188 int (*uninstantiate)(PROV_DRBG *ctx),
189 int (*reseed)(PROV_DRBG *drbg, const unsigned char *ent, size_t ent_len,
190 const unsigned char *adin, size_t adin_len),
191 int (*generate)(PROV_DRBG *, unsigned char *out, size_t outlen,
192 const unsigned char *adin, size_t adin_len));
193 void ossl_rand_drbg_free(PROV_DRBG *drbg);
195 int ossl_prov_drbg_instantiate(PROV_DRBG *drbg, unsigned int strength,
196 int prediction_resistance,
197 const unsigned char *pers, size_t perslen);
199 int ossl_prov_drbg_uninstantiate(PROV_DRBG *drbg);
201 int ossl_prov_drbg_reseed(PROV_DRBG *drbg, int prediction_resistance,
202 const unsigned char *ent, size_t ent_len,
203 const unsigned char *adin, size_t adinlen);
205 int ossl_prov_drbg_generate(PROV_DRBG *drbg, unsigned char *out, size_t outlen,
206 unsigned int strength, int prediction_resistance,
207 const unsigned char *adin, size_t adinlen);
210 OSSL_FUNC_rand_get_seed_fn ossl_drbg_get_seed;
211 OSSL_FUNC_rand_clear_seed_fn ossl_drbg_clear_seed;
213 /* Verify that an array of numeric values is all zero */
214 #define PROV_DRBG_VERYIFY_ZEROIZATION(v) \
218 for (i = 0; i < OSSL_NELEM(v); i++) \
224 OSSL_FUNC_rand_enable_locking_fn ossl_drbg_enable_locking;
225 OSSL_FUNC_rand_lock_fn ossl_drbg_lock;
226 OSSL_FUNC_rand_unlock_fn ossl_drbg_unlock;
228 /* Common parameters for all of our DRBGs */
229 int ossl_drbg_get_ctx_params(PROV_DRBG *drbg, OSSL_PARAM params[]);
230 int ossl_drbg_set_ctx_params(PROV_DRBG *drbg, const OSSL_PARAM params[]);
232 #define OSSL_PARAM_DRBG_SETTABLE_CTX_COMMON \
233 OSSL_PARAM_uint(OSSL_DRBG_PARAM_RESEED_REQUESTS, NULL), \
234 OSSL_PARAM_uint64(OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL, NULL)
236 #define OSSL_PARAM_DRBG_GETTABLE_CTX_COMMON \
237 OSSL_PARAM_int(OSSL_RAND_PARAM_STATE, NULL), \
238 OSSL_PARAM_uint(OSSL_RAND_PARAM_STRENGTH, NULL), \
239 OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_REQUEST, NULL), \
240 OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MIN_ENTROPYLEN, NULL), \
241 OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_ENTROPYLEN, NULL), \
242 OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MIN_NONCELEN, NULL), \
243 OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_NONCELEN, NULL), \
244 OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_PERSLEN, NULL), \
245 OSSL_PARAM_size_t(OSSL_DRBG_PARAM_MAX_ADINLEN, NULL), \
246 OSSL_PARAM_uint(OSSL_DRBG_PARAM_RESEED_COUNTER, NULL), \
247 OSSL_PARAM_time_t(OSSL_DRBG_PARAM_RESEED_TIME, NULL), \
248 OSSL_PARAM_uint(OSSL_DRBG_PARAM_RESEED_REQUESTS, NULL), \
249 OSSL_PARAM_uint64(OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL, NULL)
251 /* Continuous test "entropy" calls */
252 size_t ossl_crngt_get_entropy(PROV_DRBG *drbg,
253 unsigned char **pout,
254 int entropy, size_t min_len, size_t max_len,
255 int prediction_resistance);
256 void ossl_crngt_cleanup_entropy(PROV_DRBG *drbg,
257 unsigned char *out, size_t outlen);