/*

 * Copyright 1995-2025 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

 */

/* We need to use some engine deprecated APIs */

#define OPENSSL_SUPPRESS_DEPRECATED

#include <openssl/err.h>

#include <openssl/opensslconf.h>

#include <openssl/core_names.h>

#include <openssl/provider.h>

#include "internal/cryptlib.h"

#include "internal/provider.h"

#include "internal/thread_once.h"

#include "internal/threads_common.h"

#include "crypto/rand.h"

#include "crypto/cryptlib.h"

#include "rand_local.h"

#include "crypto/context.h"

#include "internal/provider.h"

#ifndef OPENSSL_DEFAULT_SEED_SRC

# define OPENSSL_DEFAULT_SEED_SRC SEED-SRC

#endif

typedef struct rand_global_st {

    /*

     * The three shared DRBG instances

     *

     * There are three shared DRBG instances: <primary>, <public>, and

     * <private>.  The <public> and <private> DRBGs are secondary ones.

     * These are used for non-secret (e.g. nonces) and secret

     * (e.g. private keys) data respectively.

     */

    CRYPTO_RWLOCK *lock;

    EVP_RAND_CTX *seed;

    /*

     * The <primary> DRBG

     *

     * Not used directly by the application, only for reseeding the two other

     * DRBGs. It reseeds itself by pulling either randomness from os entropy

     * sources or by consuming randomness which was added by RAND_add().

     *

     * The <primary> DRBG is a global instance which is accessed concurrently by

     * all threads. The necessary locking is managed automatically by its child

     * DRBG instances during reseeding.

     */

    EVP_RAND_CTX *primary;

    /*

     * The provider which we'll use to generate randomness.

     */

#ifndef FIPS_MODULE

    OSSL_PROVIDER *random_provider;

    char *random_provider_name;

#endif      /* !FIPS_MODULE */

    /* Which RNG is being used by default and it's configuration settings */

    char *rng_name;

    char *rng_cipher;

    char *rng_digest;

    char *rng_propq;

    /* Allow the randomness source to be changed */

    char *seed_name;

    char *seed_propq;

} RAND_GLOBAL;

static EVP_RAND_CTX *rand_get0_primary(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl);

static EVP_RAND_CTX *rand_get0_public(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl);

static EVP_RAND_CTX *rand_get0_private(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl);

static RAND_GLOBAL *rand_get_global(OSSL_LIB_CTX *libctx)

{

    return ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_DRBG_INDEX);

}

#ifndef FIPS_MODULE

# include <stdio.h>

# include <time.h>

# include <limits.h>

# include <openssl/conf.h>

# include <openssl/trace.h>

# include <openssl/engine.h>

# include "crypto/rand_pool.h"

# include "prov/seeding.h"

# include "internal/e_os.h"

# include "internal/property.h"

/*

 * The default name for the random provider.

 * This ensures that the FIPS provider will supply libcrypto's random byte

 * requirements.

 */

static const char random_provider_fips_name[] = "fips";

static int set_random_provider_name(RAND_GLOBAL *dgbl, const char *name)

{

    if (dgbl->random_provider_name != NULL

            && OPENSSL_strcasecmp(dgbl->random_provider_name, name) == 0)

        return 1;

    OPENSSL_free(dgbl->random_provider_name);

    dgbl->random_provider_name = OPENSSL_strdup(name);

    return dgbl->random_provider_name != NULL;

}

# ifndef OPENSSL_NO_ENGINE

/* non-NULL if default_RAND_meth is ENGINE-provided */

static ENGINE *funct_ref;

static CRYPTO_RWLOCK *rand_engine_lock;

# endif     /* !OPENSSL_NO_ENGINE */

# ifndef OPENSSL_NO_DEPRECATED_3_0

static CRYPTO_RWLOCK *rand_meth_lock;

static const RAND_METHOD *default_RAND_meth;

# endif     /* !OPENSSL_NO_DEPRECATED_3_0 */

static CRYPTO_ONCE rand_init = CRYPTO_ONCE_STATIC_INIT;

static int rand_inited = 0;

DEFINE_RUN_ONCE_STATIC(do_rand_init)

{

# ifndef OPENSSL_NO_ENGINE

    rand_engine_lock = CRYPTO_THREAD_lock_new();

    if (rand_engine_lock == NULL)

        return 0;

# endif     /* !OPENSSL_NO_ENGINE */

# ifndef OPENSSL_NO_DEPRECATED_3_0

    rand_meth_lock = CRYPTO_THREAD_lock_new();

    if (rand_meth_lock == NULL)

        goto err;

# endif     /* !OPENSSL_NO_DEPRECATED_3_0 */

    if (!ossl_rand_pool_init())

        goto err;

    rand_inited = 1;

    return 1;

 err:

# ifndef OPENSSL_NO_DEPRECATED_3_0

    CRYPTO_THREAD_lock_free(rand_meth_lock);

    rand_meth_lock = NULL;

# endif     /* !OPENSSL_NO_DEPRECATED_3_0 */

# ifndef OPENSSL_NO_ENGINE

    CRYPTO_THREAD_lock_free(rand_engine_lock);

    rand_engine_lock = NULL;

# endif     /* !OPENSSL_NO_ENGINE */

    return 0;

}

void ossl_rand_cleanup_int(void)

{

# ifndef OPENSSL_NO_DEPRECATED_3_0

    const RAND_METHOD *meth = default_RAND_meth;

    if (!rand_inited)

        return;

    if (meth != NULL && meth->cleanup != NULL)

        meth->cleanup();

    RAND_set_rand_method(NULL);

# endif     /* !OPENSSL_NO_DEPRECATED_3_0 */

    ossl_rand_pool_cleanup();

# ifndef OPENSSL_NO_ENGINE

    CRYPTO_THREAD_lock_free(rand_engine_lock);

    rand_engine_lock = NULL;

# endif     /* !OPENSSL_NO_ENGINE */

# ifndef OPENSSL_NO_DEPRECATED_3_0

    CRYPTO_THREAD_lock_free(rand_meth_lock);

    rand_meth_lock = NULL;

# endif     /* !OPENSSL_NO_DEPRECATED_3_0 */

    ossl_release_default_drbg_ctx();

    rand_inited = 0;

}

/*

 * RAND_close_seed_files() ensures that any seed file descriptors are

 * closed after use.  This only applies to libcrypto/default provider,

 * it does not apply to other providers.

 */

void RAND_keep_random_devices_open(int keep)

{

    if (RUN_ONCE(&rand_init, do_rand_init))

        ossl_rand_pool_keep_random_devices_open(keep);

}

/*

 * RAND_poll() reseeds the default RNG using random input

 *

 * The random input is obtained from polling various entropy

 * sources which depend on the operating system and are

 * configurable via the --with-rand-seed configure option.

 */

int RAND_poll(void)

{

    static const char salt[] = "polling";

# ifndef OPENSSL_NO_DEPRECATED_3_0

    const RAND_METHOD *meth = RAND_get_rand_method();

    int ret = meth == RAND_OpenSSL();

    if (meth == NULL)

        return 0;

    if (!ret) {

        /* fill random pool and seed the current legacy RNG */

        RAND_POOL *pool = ossl_rand_pool_new(RAND_DRBG_STRENGTH, 1,

                                             (RAND_DRBG_STRENGTH + 7) / 8,

                                             RAND_POOL_MAX_LENGTH);

        if (pool == NULL)

            return 0;

        if (ossl_pool_acquire_entropy(pool) == 0)

            goto err;

        if (meth->add == NULL

            || meth->add(ossl_rand_pool_buffer(pool),

                         ossl_rand_pool_length(pool),

                         (ossl_rand_pool_entropy(pool) / 8.0)) == 0)

            goto err;

        ret = 1;

     err:

        ossl_rand_pool_free(pool);

        return ret;

    }

# endif     /* !OPENSSL_NO_DEPRECATED_3_0 */

    RAND_seed(salt, sizeof(salt));

    return 1;

}

# ifndef OPENSSL_NO_DEPRECATED_3_0

static int rand_set_rand_method_internal(const RAND_METHOD *meth,

                                         ossl_unused ENGINE *e)

{

    if (!RUN_ONCE(&rand_init, do_rand_init))

        return 0;

    if (!CRYPTO_THREAD_write_lock(rand_meth_lock))

        return 0;

#  ifndef OPENSSL_NO_ENGINE

    ENGINE_finish(funct_ref);

    funct_ref = e;

#  endif

    default_RAND_meth = meth;

    CRYPTO_THREAD_unlock(rand_meth_lock);

    return 1;

}

int RAND_set_rand_method(const RAND_METHOD *meth)

{

    return rand_set_rand_method_internal(meth, NULL);

}

const RAND_METHOD *RAND_get_rand_method(void)

{

    const RAND_METHOD *tmp_meth = NULL;

    if (!RUN_ONCE(&rand_init, do_rand_init))

        return NULL;

    if (rand_meth_lock == NULL)

        return NULL;

    if (!CRYPTO_THREAD_read_lock(rand_meth_lock))

        return NULL;

    tmp_meth = default_RAND_meth;

    CRYPTO_THREAD_unlock(rand_meth_lock);

    if (tmp_meth != NULL)

        return tmp_meth;

    if (!CRYPTO_THREAD_write_lock(rand_meth_lock))

        return NULL;

    if (default_RAND_meth == NULL) {

#  ifndef OPENSSL_NO_ENGINE

        ENGINE *e;

        /* If we have an engine that can do RAND, use it. */

        if ((e = ENGINE_get_default_RAND()) != NULL

                && (tmp_meth = ENGINE_get_RAND(e)) != NULL) {

            funct_ref = e;

            default_RAND_meth = tmp_meth;

        } else {

            ENGINE_finish(e);

            default_RAND_meth = &ossl_rand_meth;

        }

#  else

        default_RAND_meth = &ossl_rand_meth;

#  endif

    }

    tmp_meth = default_RAND_meth;

    CRYPTO_THREAD_unlock(rand_meth_lock);

    return tmp_meth;

}

#  if !defined(OPENSSL_NO_ENGINE)

int RAND_set_rand_engine(ENGINE *engine)

{

    const RAND_METHOD *tmp_meth = NULL;

    if (!RUN_ONCE(&rand_init, do_rand_init))

        return 0;

    if (engine != NULL) {

        if (!ENGINE_init(engine))

            return 0;

        tmp_meth = ENGINE_get_RAND(engine);

        if (tmp_meth == NULL) {

            ENGINE_finish(engine);

            return 0;

        }

    }

    if (!CRYPTO_THREAD_write_lock(rand_engine_lock)) {

        ENGINE_finish(engine);

        return 0;

    }

    /* This function releases any prior ENGINE so call it first */

    rand_set_rand_method_internal(tmp_meth, engine);

    CRYPTO_THREAD_unlock(rand_engine_lock);

    return 1;

}

#  endif

# endif /* OPENSSL_NO_DEPRECATED_3_0 */

void RAND_seed(const void *buf, int num)

{

    EVP_RAND_CTX *drbg;

# ifndef OPENSSL_NO_DEPRECATED_3_0

    const RAND_METHOD *meth = RAND_get_rand_method();

    if (meth != NULL && meth->seed != NULL) {

        meth->seed(buf, num);

        return;

    }

# endif

    drbg = RAND_get0_primary(NULL);

    if (drbg != NULL && num > 0)

        EVP_RAND_reseed(drbg, 0, NULL, 0, buf, num);

}

void RAND_add(const void *buf, int num, double randomness)

{

    EVP_RAND_CTX *drbg;

# ifndef OPENSSL_NO_DEPRECATED_3_0

    const RAND_METHOD *meth = RAND_get_rand_method();

    if (meth != NULL && meth->add != NULL) {

        meth->add(buf, num, randomness);

        return;

    }

# endif

    drbg = RAND_get0_primary(NULL);

    if (drbg != NULL && num > 0)

# ifdef OPENSSL_RAND_SEED_NONE

        /* Without an entropy source, we have to rely on the user */

        EVP_RAND_reseed(drbg, 0, buf, num, NULL, 0);

# else

        /* With an entropy source, we downgrade this to additional input */

        EVP_RAND_reseed(drbg, 0, NULL, 0, buf, num);

# endif

}

# if !defined(OPENSSL_NO_DEPRECATED_1_1_0)

int RAND_pseudo_bytes(unsigned char *buf, int num)

{

    const RAND_METHOD *meth = RAND_get_rand_method();

    if (meth != NULL && meth->pseudorand != NULL)

        return meth->pseudorand(buf, num);

    ERR_raise(ERR_LIB_RAND, RAND_R_FUNC_NOT_IMPLEMENTED);

    return -1;

}

# endif

int RAND_status(void)

{

    EVP_RAND_CTX *rand;

# ifndef OPENSSL_NO_DEPRECATED_3_0

    const RAND_METHOD *meth = RAND_get_rand_method();

    if (meth != NULL && meth != RAND_OpenSSL())

        return meth->status != NULL ? meth->status() : 0;

# endif

    if ((rand = RAND_get0_primary(NULL)) == NULL)

        return 0;

    return EVP_RAND_get_state(rand) == EVP_RAND_STATE_READY;

}

# else  /* !FIPS_MODULE */

# ifndef OPENSSL_NO_DEPRECATED_3_0

const RAND_METHOD *RAND_get_rand_method(void)

{

    return NULL;

}

# endif

#endif /* !FIPS_MODULE */

/*

 * This function is not part of RAND_METHOD, so if we're not using

 * the default method, then just call RAND_bytes().  Otherwise make

 * sure we're instantiated and use the private DRBG.

 */

int RAND_priv_bytes_ex(OSSL_LIB_CTX *ctx, unsigned char *buf, size_t num,

                       unsigned int strength)

{

    RAND_GLOBAL *dgbl;

    EVP_RAND_CTX *rand;

#if !defined(OPENSSL_NO_DEPRECATED_3_0) && !defined(FIPS_MODULE)

    const RAND_METHOD *meth = RAND_get_rand_method();

    if (meth != NULL && meth != RAND_OpenSSL()) {

        if (meth->bytes != NULL)

            return meth->bytes(buf, num);

        ERR_raise(ERR_LIB_RAND, RAND_R_FUNC_NOT_IMPLEMENTED);

        return -1;

    }

#endif

    dgbl = rand_get_global(ctx);

    if (dgbl == NULL)

        return 0;

#ifndef FIPS_MODULE

    if (dgbl->random_provider != NULL)

        return ossl_provider_random_bytes(dgbl->random_provider,

                                          OSSL_PROV_RANDOM_PRIVATE,

                                          buf, num, strength);

#endif      /* !FIPS_MODULE */

    rand = rand_get0_private(ctx, dgbl);

    if (rand != NULL)

        return EVP_RAND_generate(rand, buf, num, strength, 0, NULL, 0);

    return 0;

}

int RAND_priv_bytes(unsigned char *buf, int num)

{

    if (num < 0)

        return 0;

    return RAND_priv_bytes_ex(NULL, buf, (size_t)num, 0);

}

int RAND_bytes_ex(OSSL_LIB_CTX *ctx, unsigned char *buf, size_t num,

                  unsigned int strength)

{

    RAND_GLOBAL *dgbl;

    EVP_RAND_CTX *rand;

#if !defined(OPENSSL_NO_DEPRECATED_3_0) && !defined(FIPS_MODULE)

    const RAND_METHOD *meth = RAND_get_rand_method();

    if (meth != NULL && meth != RAND_OpenSSL()) {

        if (meth->bytes != NULL)

            return meth->bytes(buf, num);

        ERR_raise(ERR_LIB_RAND, RAND_R_FUNC_NOT_IMPLEMENTED);

        return -1;

    }

#endif

    dgbl = rand_get_global(ctx);

    if (dgbl == NULL)

        return 0;

#ifndef FIPS_MODULE

    if (dgbl->random_provider != NULL)

        return ossl_provider_random_bytes(dgbl->random_provider,

                                          OSSL_PROV_RANDOM_PUBLIC,

                                          buf, num, strength);

#endif      /* !FIPS_MODULE */

    rand = rand_get0_public(ctx, dgbl);

    if (rand != NULL)

        return EVP_RAND_generate(rand, buf, num, strength, 0, NULL, 0);

    return 0;

}

int RAND_bytes(unsigned char *buf, int num)

{

    if (num < 0)

        return 0;

    return RAND_bytes_ex(NULL, buf, (size_t)num, 0);

}

/*

 * Initialize the OSSL_LIB_CTX global DRBGs on first use.

 * Returns the allocated global data on success or NULL on failure.

 */

void *ossl_rand_ctx_new(OSSL_LIB_CTX *libctx)

{

    RAND_GLOBAL *dgbl = OPENSSL_zalloc(sizeof(*dgbl));

    if (dgbl == NULL)

        return NULL;

#ifndef FIPS_MODULE

    /*

     * We need to ensure that base libcrypto thread handling has been

     * initialised.

     */

    OPENSSL_init_crypto(OPENSSL_INIT_BASE_ONLY, NULL);

    /* Prepopulate the random provider name */

    dgbl->random_provider_name = OPENSSL_strdup(random_provider_fips_name);

    if (dgbl->random_provider_name == NULL)

        goto err0;

#endif

    dgbl->lock = CRYPTO_THREAD_lock_new();

    if (dgbl->lock == NULL)

        goto err1;

    return dgbl;

 err1:

    CRYPTO_THREAD_lock_free(dgbl->lock);

#ifndef FIPS_MODULE

 err0:

    OPENSSL_free(dgbl->random_provider_name);

#endif

    OPENSSL_free(dgbl);

    return NULL;

}

void ossl_rand_ctx_free(void *vdgbl)

{

    RAND_GLOBAL *dgbl = vdgbl;

    if (dgbl == NULL)

        return;

    CRYPTO_THREAD_lock_free(dgbl->lock);

    EVP_RAND_CTX_free(dgbl->primary);

    EVP_RAND_CTX_free(dgbl->seed);

#ifndef FIPS_MODULE

    OPENSSL_free(dgbl->random_provider_name);

#endif      /* !FIPS_MODULE */

    OPENSSL_free(dgbl->rng_name);

    OPENSSL_free(dgbl->rng_cipher);

    OPENSSL_free(dgbl->rng_digest);

    OPENSSL_free(dgbl->rng_propq);

    OPENSSL_free(dgbl->seed_name);

    OPENSSL_free(dgbl->seed_propq);

    OPENSSL_free(dgbl);

}

static void rand_delete_thread_state(void *arg)

{

    OSSL_LIB_CTX *ctx = arg;

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    EVP_RAND_CTX *rand;

    if (dgbl == NULL)

        return;

    rand = CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx);

    CRYPTO_THREAD_set_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx, NULL);

    EVP_RAND_CTX_free(rand);

    rand = CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PRIV_KEY, ctx);

    CRYPTO_THREAD_set_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PRIV_KEY, ctx, NULL);

    EVP_RAND_CTX_free(rand);

}

#if !defined(FIPS_MODULE) || !defined(OPENSSL_NO_FIPS_JITTER)

static EVP_RAND_CTX *rand_new_seed(OSSL_LIB_CTX *libctx)

{

    EVP_RAND *rand;

    const char *propq;

    char *name;

    EVP_RAND_CTX *ctx = NULL;

# ifdef OPENSSL_NO_FIPS_JITTER

    RAND_GLOBAL *dgbl = rand_get_global(libctx);

    if (dgbl == NULL)

        return NULL;

    propq = dgbl->seed_propq;

    name = dgbl->seed_name != NULL ? dgbl->seed_name

                                   : OPENSSL_MSTR(OPENSSL_DEFAULT_SEED_SRC);

# else /* !OPENSSL_NO_FIPS_JITTER */

    name = "JITTER";

    propq = "";

# endif /* OPENSSL_NO_FIPS_JITTER */

    rand = EVP_RAND_fetch(libctx, name, propq);

    if (rand == NULL) {

        ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_FETCH_DRBG);

        goto err;

    }

    ctx = EVP_RAND_CTX_new(rand, NULL);

    EVP_RAND_free(rand);

    if (ctx == NULL) {

        ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_CREATE_DRBG);

        goto err;

    }

    if (!EVP_RAND_instantiate(ctx, 0, 0, NULL, 0, NULL)) {

        ERR_raise(ERR_LIB_RAND, RAND_R_ERROR_INSTANTIATING_DRBG);

        goto err;

    }

    return ctx;

 err:

    EVP_RAND_CTX_free(ctx);

    return NULL;

}

#endif  /* !FIPS_MODULE || !OPENSSL_NO_FIPS_JITTER */

#ifndef FIPS_MODULE

EVP_RAND_CTX *ossl_rand_get0_seed_noncreating(OSSL_LIB_CTX *ctx)

{

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    EVP_RAND_CTX *ret;

    if (dgbl == NULL)

        return NULL;

    if (!CRYPTO_THREAD_read_lock(dgbl->lock))

        return NULL;

    ret = dgbl->seed;

    CRYPTO_THREAD_unlock(dgbl->lock);

    return ret;

}

#endif  /* !FIPS_MODULE */

static EVP_RAND_CTX *rand_new_drbg(OSSL_LIB_CTX *libctx, EVP_RAND_CTX *parent,

                                   unsigned int reseed_interval,

                                   time_t reseed_time_interval)

{

    EVP_RAND *rand;

    RAND_GLOBAL *dgbl = rand_get_global(libctx);

    EVP_RAND_CTX *ctx;

    OSSL_PARAM params[9], *p = params;

    const OSSL_PARAM *settables;

    const char *prov_name;

    char *name, *cipher;

    int use_df = 1;

    if (dgbl == NULL)

        return NULL;

    name = dgbl->rng_name != NULL ? dgbl->rng_name : "CTR-DRBG";

    rand = EVP_RAND_fetch(libctx, name, dgbl->rng_propq);

    if (rand == NULL) {

        ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_FETCH_DRBG);

        return NULL;

    }

    prov_name = ossl_provider_name(EVP_RAND_get0_provider(rand));

    ctx = EVP_RAND_CTX_new(rand, parent);

    EVP_RAND_free(rand);

    if (ctx == NULL) {

        ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_CREATE_DRBG);

        return NULL;

    }

    settables = EVP_RAND_CTX_settable_params(ctx);

    if (OSSL_PARAM_locate_const(settables, OSSL_DRBG_PARAM_CIPHER)) {

        cipher = dgbl->rng_cipher != NULL ? dgbl->rng_cipher : "AES-256-CTR";

        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_CIPHER,

                                                cipher, 0);

    }

    if (dgbl->rng_digest != NULL

            && OSSL_PARAM_locate_const(settables, OSSL_DRBG_PARAM_DIGEST))

        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_DIGEST,

                                                dgbl->rng_digest, 0);

    if (prov_name != NULL)

        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_PROV_PARAM_CORE_PROV_NAME,

                                                (char *)prov_name, 0);

    if (dgbl->rng_propq != NULL)

        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_PROPERTIES,

                                                dgbl->rng_propq, 0);

    if (OSSL_PARAM_locate_const(settables, OSSL_ALG_PARAM_MAC))

        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_MAC, "HMAC", 0);

    if (OSSL_PARAM_locate_const(settables, OSSL_DRBG_PARAM_USE_DF))

        *p++ = OSSL_PARAM_construct_int(OSSL_DRBG_PARAM_USE_DF, &use_df);

    *p++ = OSSL_PARAM_construct_uint(OSSL_DRBG_PARAM_RESEED_REQUESTS,

                                     &reseed_interval);

    *p++ = OSSL_PARAM_construct_time_t(OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL,

                                       &reseed_time_interval);

    *p = OSSL_PARAM_construct_end();

    if (!EVP_RAND_instantiate(ctx, 0, 0, NULL, 0, params)) {

        ERR_raise(ERR_LIB_RAND, RAND_R_ERROR_INSTANTIATING_DRBG);

        EVP_RAND_CTX_free(ctx);

        return NULL;

    }

    return ctx;

}

#if defined(FIPS_MODULE)

static EVP_RAND_CTX *rand_new_crngt(OSSL_LIB_CTX *libctx, EVP_RAND_CTX *parent)

{

    EVP_RAND *rand;

    EVP_RAND_CTX *ctx;

    rand = EVP_RAND_fetch(libctx, "CRNG-TEST", "-fips");

    if (rand == NULL) {

        ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_FETCH_DRBG);

        return NULL;

    }

    ctx = EVP_RAND_CTX_new(rand, parent);

    EVP_RAND_free(rand);

    if (ctx == NULL) {

        ERR_raise(ERR_LIB_RAND, RAND_R_UNABLE_TO_CREATE_DRBG);

        return NULL;

    }

    if (!EVP_RAND_instantiate(ctx, 0, 0, NULL, 0, NULL)) {

        ERR_raise(ERR_LIB_RAND, RAND_R_ERROR_INSTANTIATING_DRBG);

        EVP_RAND_CTX_free(ctx);

        return NULL;

    }

    return ctx;

}

#endif  /* FIPS_MODULE */

/*

 * Get the primary random generator.

 * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.

 *

 */

static EVP_RAND_CTX *rand_get0_primary(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl)

{

    EVP_RAND_CTX *ret, *seed, *newseed = NULL, *primary;

    if (dgbl == NULL)

        return NULL;

    if (!CRYPTO_THREAD_read_lock(dgbl->lock))

        return NULL;

    ret = dgbl->primary;

    seed = dgbl->seed;

    CRYPTO_THREAD_unlock(dgbl->lock);

    if (ret != NULL)

        return ret;

#if !defined(FIPS_MODULE) || !defined(OPENSSL_NO_FIPS_JITTER)

    /* Create a seed source for libcrypto or jitter enabled FIPS provider */

    if (seed == NULL) {

        ERR_set_mark();

        seed = newseed = rand_new_seed(ctx);

        ERR_pop_to_mark();

    }

#endif  /* !FIPS_MODULE || !OPENSSL_NO_FIPS_JITTER */

#if defined(FIPS_MODULE)

    /* The FIPS provider has entropy health tests instead of the primary */

    ret = rand_new_crngt(ctx, seed);

#else   /* FIPS_MODULE */

    ret = rand_new_drbg(ctx, seed, PRIMARY_RESEED_INTERVAL,

                        PRIMARY_RESEED_TIME_INTERVAL);

#endif  /* FIPS_MODULE */

    /*

     * The primary DRBG may be shared between multiple threads so we must

     * enable locking.

     */

    if (ret == NULL || !EVP_RAND_enable_locking(ret)) {

        if (ret != NULL) {

            ERR_raise(ERR_LIB_EVP, EVP_R_UNABLE_TO_ENABLE_LOCKING);

            EVP_RAND_CTX_free(ret);

        }

        if (newseed == NULL)

            return NULL;

        /* else carry on and store seed */

        ret = NULL;

    }

    if (!CRYPTO_THREAD_write_lock(dgbl->lock))

        return NULL;

    primary = dgbl->primary;

    if (primary != NULL) {

        CRYPTO_THREAD_unlock(dgbl->lock);

        EVP_RAND_CTX_free(ret);

        EVP_RAND_CTX_free(newseed);

        return primary;

    }

    if (newseed != NULL)

        dgbl->seed = newseed;

    dgbl->primary = ret;

    CRYPTO_THREAD_unlock(dgbl->lock);

    return ret;

}

/*

 * Get the primary random generator.

 * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.

 *

 */

EVP_RAND_CTX *RAND_get0_primary(OSSL_LIB_CTX *ctx)

{

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    return dgbl == NULL ? NULL : rand_get0_primary(ctx, dgbl);

}

static EVP_RAND_CTX *rand_get0_public(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl)

{

    EVP_RAND_CTX *rand, *primary;

    OSSL_LIB_CTX *origctx = ctx;

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return NULL;

    if (dgbl == NULL)

        return NULL;

    rand = CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx);

    if (rand == NULL) {

        primary = rand_get0_primary(origctx, dgbl);

        if (primary == NULL)

            return NULL;

        /*

         * If the private is also NULL then this is the first time we've

         * used this thread.

         */

        if (CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PRIV_KEY, ctx) == NULL

                && !ossl_init_thread_start(NULL, ctx, rand_delete_thread_state))

            return NULL;

        rand = rand_new_drbg(ctx, primary, SECONDARY_RESEED_INTERVAL,

                             SECONDARY_RESEED_TIME_INTERVAL);

        CRYPTO_THREAD_set_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx, rand);

    }

    return rand;

}

/*

 * Get the public random generator.

 * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.

 */

EVP_RAND_CTX *RAND_get0_public(OSSL_LIB_CTX *ctx)

{

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    return dgbl == NULL ? NULL : rand_get0_public(ctx, dgbl);

}

static EVP_RAND_CTX *rand_get0_private(OSSL_LIB_CTX *ctx, RAND_GLOBAL *dgbl)

{

    EVP_RAND_CTX *rand, *primary;

    OSSL_LIB_CTX *origctx = ctx;

    ctx = ossl_lib_ctx_get_concrete(ctx);

    if (ctx == NULL)

        return NULL;

    rand = CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PRIV_KEY, ctx);

    if (rand == NULL) {

        primary = rand_get0_primary(origctx, dgbl);

        if (primary == NULL)

            return NULL;

        /*

         * If the public is also NULL then this is the first time we've

         * used this thread.

         */

        if (CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx) == NULL

                && !ossl_init_thread_start(NULL, ctx, rand_delete_thread_state))

            return NULL;

        rand = rand_new_drbg(ctx, primary, SECONDARY_RESEED_INTERVAL,

                             SECONDARY_RESEED_TIME_INTERVAL);

        CRYPTO_THREAD_set_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PRIV_KEY, ctx, rand);

    }

    return rand;

}

/*

 * Get the private random generator.

 * Returns pointer to its EVP_RAND_CTX on success, NULL on failure.

 */

EVP_RAND_CTX *RAND_get0_private(OSSL_LIB_CTX *ctx)

{

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    return dgbl == NULL ? NULL : rand_get0_private(ctx, dgbl);

}

#ifdef FIPS_MODULE

EVP_RAND_CTX *ossl_rand_get0_private_noncreating(OSSL_LIB_CTX *ctx)

{

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    if (dgbl == NULL)

        return NULL;

    return CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PRIV_KEY, ctx);

}

#endif

int RAND_set0_public(OSSL_LIB_CTX *ctx, EVP_RAND_CTX *rand)

{

    RAND_GLOBAL *dgbl = rand_get_global(ctx);

    EVP_RAND_CTX *old;

    int r;

    if (dgbl == NULL)

        return 0;

    old = CRYPTO_THREAD_get_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx);

    if ((r = CRYPTO_THREAD_set_local_ex(CRYPTO_THREAD_LOCAL_DRBG_PUB_KEY, ctx, rand)) > 0)

        EVP_RAND_CTX_free(old);

    return r;

}

int RAND_set0_private(OSSL_LIB_CTX *ctx, EVP_RAND_CTX *rand)