openssl/providers/implementations/rands/drbg_local.h
Pauli 714a1bb380 rand: set up EVP and DRBG infrastructure for RAND from providers.
Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/11682)
2020-06-24 20:05:41 +10:00

288 lines
11 KiB
C

/*
* Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#ifndef OSSL_CRYPTO_PROV_LOCAL_H
# define OSSL_CRYPTO_PROV_LOCAL_H
# include <openssl/evp.h>
# include <openssl/core_numbers.h>
# include <openssl/core_names.h>
# include <openssl/params.h>
# include "internal/tsan_assist.h"
# include "internal/numbers.h"
/* How many times to read the TSC as a randomness source. */
# define TSC_READ_COUNT 4
/* Maximum reseed intervals */
# define MAX_RESEED_INTERVAL (1 << 24)
# define MAX_RESEED_TIME_INTERVAL (1 << 20) /* approx. 12 days */
/* Default reseed intervals */
# define MASTER_RESEED_INTERVAL (1 << 8)
# define SLAVE_RESEED_INTERVAL (1 << 16)
# define MASTER_RESEED_TIME_INTERVAL (60*60) /* 1 hour */
# define SLAVE_RESEED_TIME_INTERVAL (7*60) /* 7 minutes */
/*
* The number of bytes that constitutes an atomic lump of entropy with respect
* to the FIPS 140-2 section 4.9.2 Conditional Tests. The size is somewhat
* arbitrary, the smaller the value, the less entropy is consumed on first
* read but the higher the probability of the test failing by accident.
*
* The value is in bytes.
*/
#define CRNGT_BUFSIZ 16
/*
* Maximum input size for the DRBG (entropy, nonce, personalization string)
*
* NIST SP800 90Ar1 allows a maximum of (1 << 35) bits i.e., (1 << 32) bytes.
*
* We lower it to 'only' INT32_MAX bytes, which is equivalent to 2 gigabytes.
*/
# define DRBG_MAX_LENGTH INT32_MAX
/* The default nonce */
#ifdef CHARSET_EBCDIC
# define DRBG_DEFAULT_PERS_STRING { 0x4f, 0x70, 0x65, 0x6e, 0x53, 0x53, \
0x4c, 0x20, 0x4e, 0x49, 0x53, 0x54, 0x20, 0x53, 0x50, 0x20, 0x38, 0x30, \
0x30, 0x2d, 0x39, 0x30, 0x41, 0x20, 0x44, 0x52, 0x42, 0x47, 0x00};
#else
# define DRBG_DEFAULT_PERS_STRING "OpenSSL NIST SP 800-90A DRBG"
#endif
typedef struct prov_drbg_st PROV_DRBG;
/* DRBG status values */
typedef enum drbg_status_e {
DRBG_UNINITIALISED,
DRBG_READY,
DRBG_ERROR
} DRBG_STATUS;
/*
* The DRBG methods
*/
typedef struct rand_drbg_hmac_st {
EVP_MD *md;
HMAC_CTX *ctx;
size_t blocklen;
unsigned char K[EVP_MAX_MD_SIZE];
unsigned char V[EVP_MAX_MD_SIZE];
} PROV_DRBG_HMAC;
/*
* The state of a DRBG AES-CTR.
*/
typedef struct rand_drbg_ctr_st {
EVP_CIPHER_CTX *ctx_ecb;
EVP_CIPHER_CTX *ctx_ctr;
EVP_CIPHER_CTX *ctx_df;
EVP_CIPHER *cipher_ecb;
EVP_CIPHER *cipher_ctr;
size_t keylen;
unsigned char K[32];
unsigned char V[16];
/* Temporary block storage used by ctr_df */
unsigned char bltmp[16];
size_t bltmp_pos;
unsigned char KX[48];
} PROV_DRBG_CTR;
/*
* The state of all types of DRBGs, even though we only have CTR mode
* right now.
*/
struct prov_drbg_st {
CRYPTO_RWLOCK *lock;
/* The library context this DRBG is associated with, if any */
OPENSSL_CTX *libctx;
void *parent;
const OSSL_DISPATCH *parent_dispatch;
int secure; /* 1: allocated on the secure heap, 0: otherwise */
/*
* Stores the return value of openssl_get_fork_id() as of when we last
* reseeded. The DRBG reseeds automatically whenever drbg->fork_id !=
* openssl_get_fork_id(). Used to provide fork-safety and reseed this
* DRBG in the child process.
*/
int fork_id;
unsigned short flags; /* various external flags */
/*
* The random_data is used by PROV_add()/drbg_add() to attach random
* data to the global drbg, such that the rand_drbg_get_entropy() callback
* can pull it during instantiation and reseeding. This is necessary to
* reconcile the different philosophies of the PROV and the PROV_DRBG
* with respect to how randomness is added to the RNG during reseeding
* (see PR #4328).
*/
struct rand_pool_st *seed_pool;
/*
* Auxiliary pool for additional data.
*/
struct rand_pool_st *adin_pool;
/*
* The following parameters are setup by the per-type "init" function.
*
* The supported types and their init functions are:
* (1) CTR_DRBG: drbg_ctr_init().
* (2) HMAC_DRBG: drbg_hmac_init().
* (3) HASH_DRBG: drbg_hash_init().
*
* The parameters are closely related to the ones described in
* section '10.2.1 CTR_DRBG' of [NIST SP 800-90Ar1], with one
* crucial difference: In the NIST standard, all counts are given
* in bits, whereas in OpenSSL entropy counts are given in bits
* and buffer lengths are given in bytes.
*
* Since this difference has lead to some confusion in the past,
* (see [GitHub Issue #2443], formerly [rt.openssl.org #4055])
* the 'len' suffix has been added to all buffer sizes for
* clarification.
*/
int strength;
size_t max_request;
size_t min_entropylen, max_entropylen;
size_t min_noncelen, max_noncelen;
size_t max_perslen, max_adinlen;
/*
* Counts the number of generate requests since the last reseed
* (Starts at 1). This value is the reseed_counter as defined in
* NIST SP 800-90Ar1
*/
unsigned int reseed_gen_counter;
/*
* Maximum number of generate requests until a reseed is required.
* This value is ignored if it is zero.
*/
unsigned int reseed_interval;
/* Stores the time when the last reseeding occurred */
time_t reseed_time;
/*
* Specifies the maximum time interval (in seconds) between reseeds.
* This value is ignored if it is zero.
*/
time_t reseed_time_interval;
/*
* Counts the number of reseeds since instantiation.
* This value is ignored if it is zero.
*
* This counter is used only for seed propagation from the <master> DRBG
* to its two children, the <public> and <private> DRBG. This feature is
* very special and its sole purpose is to ensure that any randomness which
* is added by PROV_add() or PROV_seed() will have an immediate effect on
* the output of PROV_bytes() resp. PROV_priv_bytes().
*/
TSAN_QUALIFIER unsigned int reseed_prop_counter;
unsigned int reseed_next_counter;
size_t seedlen;
DRBG_STATUS state;
void *data;
#ifndef FIPS_MODULE
/* Application data, mainly used in the KATs. */
CRYPTO_EX_DATA ex_data;
#endif
};
/* DRBG helpers */
int rand_drbg_restart(PROV_DRBG *drbg,
const unsigned char *buffer, size_t len, size_t entropy);
size_t rand_drbg_seedlen(PROV_DRBG *drbg);
PROV_DRBG *prov_rand_drbg_new(void *provctx, int secure, void *parent,
const OSSL_DISPATCH *parent_dispatch,
int (*dnew)(PROV_DRBG *ctx, int secure));
void prov_rand_free(PROV_DRBG *drbg);
int PROV_DRBG_instantiate(PROV_DRBG *drbg, int strength,
int prediction_resistance,
const unsigned char *pers, size_t perslen,
int (*ifnc)(PROV_DRBG *drbg,
const unsigned char *ent, size_t ent_len,
const unsigned char *nonce,
size_t nonce_len,
const unsigned char *pstr,
size_t pstr_len));
int PROV_DRBG_reseed(PROV_DRBG *drbg, int prediction_resistance,
const unsigned char *ent, size_t ent_len,
const unsigned char *adin, size_t adinlen,
int (*reseed)(PROV_DRBG *drbg, const unsigned char *ent,
size_t ent_len, const unsigned char *adin,
size_t adin_len));
int PROV_DRBG_generate(PROV_DRBG *drbg, unsigned char *out, size_t outlen,
int strength, int prediction_resistance,
const unsigned char *adin, size_t adinlen,
int (*generate)(PROV_DRBG *, unsigned char *out,
size_t outlen, const unsigned char *adin,
size_t adin_len),
int (*reseed)(PROV_DRBG *drbg, const unsigned char *ent,
size_t ent_len, const unsigned char *adin,
size_t adin_len));
/* locking api */
OSSL_OP_rand_enable_locking_fn drbg_enable_locking;
OSSL_OP_rand_lock_fn drbg_lock;
OSSL_OP_rand_unlock_fn drbg_unlock;
int drbg_get_ctx_params(PROV_DRBG *drbg, OSSL_PARAM params[]);
int drbg_set_ctx_params(PROV_DRBG *drbg, const OSSL_PARAM params[]);
#define OSSL_PARAM_DRBG_SETABLE_CTX_COMMON \
OSSL_PARAM_uint(OSSL_RAND_PARAM_RESEED_REQUESTS, NULL), \
OSSL_PARAM_uint64(OSSL_RAND_PARAM_RESEED_TIME_INTERVAL, NULL)
#define OSSL_PARAM_DRBG_GETABLE_CTX_COMMON \
OSSL_PARAM_int(OSSL_RAND_PARAM_STATUS, NULL), \
OSSL_PARAM_uint(OSSL_RAND_PARAM_STRENGTH, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_REQUEST, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MIN_ENTROPYLEN, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_ENTROPYLEN, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MIN_NONCELEN, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_NONCELEN, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_PERSLEN, NULL), \
OSSL_PARAM_size_t(OSSL_RAND_PARAM_MAX_ADINLEN, NULL), \
OSSL_PARAM_uint(OSSL_RAND_PARAM_RESEED_CTR, NULL), \
OSSL_PARAM_uint(OSSL_RAND_PARAM_RESEED_REQUESTS, NULL), \
OSSL_PARAM_uint64(OSSL_RAND_PARAM_RESEED_TIME_INTERVAL, NULL)
size_t prov_crngt_get_entropy(PROV_DRBG *drbg,
unsigned char **pout,
int entropy, size_t min_len, size_t max_len,
int prediction_resistance);
void prov_crngt_cleanup_entropy(PROV_DRBG *drbg,
unsigned char *out, size_t outlen);
/*
* Entropy call back for the FIPS 140-2 section 4.9.2 Conditional Tests.
* These need to be exposed for the unit tests.
*/
#if 0
int rand_crngt_get_entropy_cb(OPENSSL_CTX *ctx, PROV_POOL *pool,
unsigned char *buf, unsigned char *md,
unsigned int *md_size);
extern int (*crngt_get_entropy)(OPENSSL_CTX *ctx, PROV_POOL *pool,
unsigned char *buf, unsigned char *md,
unsigned int *md_size);
#endif
#endif