rand_drbg: remove RAND_DRBG.

The RAND_DRBG API did not fit well into the new provider concept as
implemented by EVP_RAND and EVP_RAND_CTX. The main reason is that the
RAND_DRBG API is a mixture of 'front end' and 'back end' API calls
and some of its API calls are rather low-level. This holds in particular
for the callback mechanism (RAND_DRBG_set_callbacks()) and the RAND_DRBG
type changing mechanism (RAND_DRBG_set()).

Adding a compatibility layer to continue supporting the RAND_DRBG API as
a legacy API for a regular deprecation period turned out to come at the
price of complicating the new provider API unnecessarily. Since the
RAND_DRBG API exists only since version 1.1.1, it was decided by the OMC
to drop it entirely.

Other related changes:

Use RNG instead of DRBG in EVP_RAND documentation.  The documentation was
using DRBG in places where it should have been RNG or CSRNG.

Move the RAND_DRBG(7) documentation to EVP_RAND(7).

Reviewed-by: Matthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
(Merged from https://github.com/openssl/openssl/pull/12509)

7 files changed, 345 insertions, 1066 deletions

diff --git a/crypto/rand/build.info b/crypto/rand/build.info
index 7776ca8820..f58a026f3b 100644
--- a/crypto/rand/build.info
+++ b/crypto/rand/build.info
@@ -1,6 +1,6 @@
 LIBS=../../libcrypto
 
-$COMMON=drbg_lib.c rand_lib.c
+$COMMON=rand_lib.c rand_meth.c
 $CRYPTO=randfile.c rand_err.c rand_deprecated.c
 
 IF[{- !$disabled{'egd'} -}]
diff --git a/crypto/rand/drbg_lib.c b/crypto/rand/drbg_lib.c
deleted file mode 100644
index d2566920cd..0000000000
--- a/crypto/rand/drbg_lib.c
+++ /dev/null
@@ -1,1016 +0,0 @@
-/*
- * Copyright 2011-2020 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
- */
-
-/*
- * RAND_DRBG_set is deprecated for public use, but still ok for
- * internal use.
- */
-#include "internal/deprecated.h"
-
-#include <string.h>
-#include <openssl/crypto.h>
-#include <openssl/err.h>
-#include <openssl/rand.h>
-#include <openssl/core_names.h>
-#include "rand_local.h"
-#include "internal/thread_once.h"
-#include "crypto/rand.h"
-#include "crypto/cryptlib.h"
-
-/*
- * Support framework for NIST SP 800-90A DRBG
- *
- * See manual page RAND_DRBG(7) for a general overview.
- *
- * The OpenSSL model is to have new and free functions, and that new
- * does all initialization.  That is not the NIST model, which has
- * instantiation and un-instantiate, and re-use within a new/free
- * lifecycle.  (No doubt this comes from the desire to support hardware
- * DRBG, where allocation of resources on something like an HSM is
- * a much bigger deal than just re-setting an allocated resource.)
- */
-
-
-typedef struct drbg_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;
-
-    /*
-     * 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.
-     */
-    RAND_DRBG *primary_drbg;
-    /*
-     * The <public> DRBG
-     *
-     * Used by default for generating random bytes using RAND_bytes().
-     *
-     * The <public> secondary DRBG is thread-local, i.e., there is one instance
-     * per thread.
-     */
-    CRYPTO_THREAD_LOCAL public_drbg;
-    /*
-     * The <private> DRBG
-     *
-     * Used by default for generating private keys using RAND_priv_bytes()
-     *
-     * The <private> secondary DRBG is thread-local, i.e., there is one
-     * instance per thread.
-     */
-    CRYPTO_THREAD_LOCAL private_drbg;
-} DRBG_GLOBAL;
-
-#define RAND_DRBG_TYPE_FLAGS    ( \
-    RAND_DRBG_FLAG_PRIMARY | RAND_DRBG_FLAG_PUBLIC | RAND_DRBG_FLAG_PRIVATE )
-
-#define RAND_DRBG_TYPE_PRIMARY                    0
-#define RAND_DRBG_TYPE_PUBLIC                     1
-#define RAND_DRBG_TYPE_PRIVATE                    2
-
-/* Defaults */
-static int rand_drbg_type[3] = {
-    RAND_DRBG_TYPE, /* Primary */
-    RAND_DRBG_TYPE, /* Public */
-    RAND_DRBG_TYPE  /* Private */
-};
-static unsigned int rand_drbg_flags[3] = {
-    RAND_DRBG_FLAGS | RAND_DRBG_FLAG_PRIMARY, /* Primary */
-    RAND_DRBG_FLAGS | RAND_DRBG_FLAG_PUBLIC,  /* Public */
-    RAND_DRBG_FLAGS | RAND_DRBG_FLAG_PRIVATE  /* Private */
-};
-
-static unsigned int primary_reseed_interval = PRIMARY_RESEED_INTERVAL;
-static unsigned int secondary_reseed_interval = SECONDARY_RESEED_INTERVAL;
-
-static time_t primary_reseed_time_interval = PRIMARY_RESEED_TIME_INTERVAL;
-static time_t secondary_reseed_time_interval = SECONDARY_RESEED_TIME_INTERVAL;
-
-/* A logical OR of all used DRBG flag bits (currently there is only one) */
-static const unsigned int rand_drbg_used_flags =
-    RAND_DRBG_FLAG_CTR_NO_DF | RAND_DRBG_FLAG_HMAC | RAND_DRBG_TYPE_FLAGS;
-
-
-static RAND_DRBG *drbg_setup(OPENSSL_CTX *ctx, RAND_DRBG *parent,
-                             int drbg_type);
-
-static int get_drbg_params(int type, unsigned int flags, const char **name,
-                           OSSL_PARAM params[3])
-{
-    OSSL_PARAM *p = params;
-
-    switch (type) {
-    case 0:
-        return 1;
-    default:
-        return 0;
-
-#define CTR(v)                                                              \
-    *name = "CTR-DRBG";                                                     \
-    *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_CIPHER, v, 0)
-
-    case NID_aes_128_ctr:
-        CTR(SN_aes_128_ctr);
-        break;
-    case NID_aes_192_ctr:
-        CTR(SN_aes_192_ctr);
-        break;
-    case NID_aes_256_ctr:
-        CTR(SN_aes_256_ctr);
-        break;
-
-#define DGST(v)                                                             \
-    *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_DIGEST, v, 0);  \
-    if ((flags & RAND_DRBG_FLAG_HMAC) == 0) {                               \
-        *name = "HASH-DRBG";                                                \
-    } else {                                                                \
-        *name = "HMAC-DRBG";                                                \
-        *p++ = OSSL_PARAM_construct_utf8_string(OSSL_DRBG_PARAM_MAC,        \
-                                                SN_hmac, 0);                \
-    }
-
-    case NID_sha1:
-        DGST(SN_sha1);
-        break;
-    case NID_sha224:
-        DGST(SN_sha224);
-        break;
-    case NID_sha256:
-        DGST(SN_sha256);
-        break;
-    case NID_sha384:
-        DGST(SN_sha384);
-        break;
-    case NID_sha512:
-        DGST(SN_sha512);
-        break;
-    case NID_sha512_224:
-        DGST(SN_sha512_224);
-        break;
-    case NID_sha512_256:
-        DGST(SN_sha512_256);
-        break;
-    case NID_sha3_224:
-        DGST(SN_sha3_224);
-        break;
-    case NID_sha3_256:
-        DGST(SN_sha3_256);
-        break;
-    case NID_sha3_384:
-        DGST(SN_sha3_384);
-        break;
-    case NID_sha3_512:
-        DGST(SN_sha3_512);
-    }
-    *p = OSSL_PARAM_construct_end();
-    return 1;
-}
-
-/*
- * Initialize the OPENSSL_CTX global DRBGs on first use.
- * Returns the allocated global data on success or NULL on failure.
- */
-static void *drbg_ossl_ctx_new(OPENSSL_CTX *libctx)
-{
-    DRBG_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(0, NULL);
-#endif
-
-    dgbl->lock = CRYPTO_THREAD_lock_new();
-    if (dgbl->lock == NULL)
-        goto err0;
-
-    if (!CRYPTO_THREAD_init_local(&dgbl->private_drbg, NULL))
-        goto err1;
-
-    if (!CRYPTO_THREAD_init_local(&dgbl->public_drbg, NULL))
-        goto err2;
-
-    return dgbl;
-
- err2:
-    CRYPTO_THREAD_cleanup_local(&dgbl->private_drbg);
- err1:
-    CRYPTO_THREAD_lock_free(dgbl->lock);
- err0:
-    OPENSSL_free(dgbl);
-    return NULL;
-}
-
-static void drbg_ossl_ctx_free(void *vdgbl)
-{
-    DRBG_GLOBAL *dgbl = vdgbl;
-
-    if (dgbl == NULL)
-        return;
-
-    CRYPTO_THREAD_lock_free(dgbl->lock);
-    RAND_DRBG_free(dgbl->primary_drbg);
-    CRYPTO_THREAD_cleanup_local(&dgbl->private_drbg);
-    CRYPTO_THREAD_cleanup_local(&dgbl->public_drbg);
-
-    OPENSSL_free(dgbl);
-}
-
-static const OPENSSL_CTX_METHOD drbg_ossl_ctx_method = {
-    drbg_ossl_ctx_new,
-    drbg_ossl_ctx_free,
-};
-
-static DRBG_GLOBAL *drbg_get_global(OPENSSL_CTX *libctx)
-{
-    return openssl_ctx_get_data(libctx, OPENSSL_CTX_DRBG_INDEX,
-                                &drbg_ossl_ctx_method);
-}
-
-/*
- * Set the |drbg|'s callback data pointer for the entropy and nonce callbacks
- *
- * The ownership of the context data remains with the caller,
- * i.e., it is the caller's responsibility to keep it available as long
- * as it is need by the callbacks and free it after use.
- *
- * Setting the callback data is allowed only if the drbg has not been
- * initialized yet. Otherwise, the operation will fail.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_set_callback_data(RAND_DRBG *drbg, void *data)
-{
-    if (EVP_RAND_state(drbg->rand) != EVP_RAND_STATE_UNINITIALISED
-            || drbg->parent != NULL)
-        return 0;
-
-    drbg->callback_data = data;
-    return 1;
-}
-
-/* Retrieve the callback data pointer */
-void *RAND_DRBG_get_callback_data(RAND_DRBG *drbg)
-{
-    return drbg->callback_data;
-}
-
-/*
- * Set/initialize |drbg| to be of type |type|, with optional |flags|.
- *
- * If |type| and |flags| are zero, use the defaults
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_set(RAND_DRBG *drbg, int type, unsigned int flags)
-{
-    OSSL_PARAM params[6], *p = params;
-    unsigned int reseed_interval;
-    time_t reseed_time_interval;
-    const char *name = NULL;
-    EVP_RAND *rand;
-    EVP_RAND_CTX *pctx;
-    int use_df;
-
-    RAND_DRBG_get_entropy_fn get_entropy = drbg->get_entropy;
-    RAND_DRBG_cleanup_entropy_fn cleanup_entropy = drbg->cleanup_entropy;
-    RAND_DRBG_get_nonce_fn get_nonce = drbg->get_nonce;
-    RAND_DRBG_cleanup_nonce_fn cleanup_nonce = drbg->cleanup_nonce;
-
-    if (type == 0 && flags == 0) {
-        type = rand_drbg_type[RAND_DRBG_TYPE_PRIMARY];
-        flags = rand_drbg_flags[RAND_DRBG_TYPE_PRIMARY];
-    }
-
-    if (drbg->parent == NULL) {
-        reseed_interval = primary_reseed_interval;
-        reseed_time_interval = primary_reseed_time_interval;
-    } else {
-        reseed_interval = secondary_reseed_interval;
-        reseed_time_interval = secondary_reseed_time_interval;
-    }
-    *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);
-    use_df = (flags & RAND_DRBG_FLAG_CTR_NO_DF) == 0;
-    *p++ = OSSL_PARAM_construct_int(OSSL_DRBG_PARAM_USE_DF, &use_df);
-
-    if (!get_drbg_params(type, flags, &name, p)) {
-        RANDerr(0, RAND_R_UNSUPPORTED_DRBG_TYPE);
-        return 0;
-    }
-
-    rand = EVP_RAND_fetch(drbg->libctx, name, NULL);
-    if (rand == NULL) {
-        RANDerr(0, RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED);
-        return 0;
-    }
-
-    EVP_RAND_CTX_free(drbg->rand);
-    drbg->rand = NULL;
-
-    drbg->flags = flags;
-    drbg->type = type;
-
-    pctx = drbg->parent != NULL ? drbg->parent->rand : NULL;
-    drbg->rand = EVP_RAND_CTX_new(rand, pctx);
-    EVP_RAND_free(rand);
-    if (drbg->rand == NULL) {
-        RANDerr(0, RAND_R_NO_DRBG_IMPLEMENTATION_SELECTED);
-        goto err;
-    }
-
-    if (!EVP_RAND_set_ctx_params(drbg->rand, params)) {
-        RANDerr(0, RAND_R_ERROR_INITIALISING_DRBG);
-        goto err;
-    }
-
-    if (!RAND_DRBG_set_callbacks(drbg,
-                                 get_entropy, cleanup_entropy,
-                                 get_nonce, cleanup_nonce)) {
-        RANDerr(0, RAND_R_ERROR_INITIALISING_DRBG);
-        goto err;
-    }
-
-    return 1;
-err:
-    EVP_RAND_CTX_free(drbg->rand);
-    drbg->rand = NULL;
-    drbg->type = 0;
-    drbg->flags = 0;
-    return 0;
-}
-
-/*
- * Set/initialize default |type| and |flag| for new drbg instances.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_set_defaults(int type, unsigned int flags)
-{
-    int all;
-    const char *name;
-    OSSL_PARAM params[3];
-
-    if (!get_drbg_params(type, flags, &name, params)) {
-        RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS, RAND_R_UNSUPPORTED_DRBG_TYPE);
-        return 0;
-    }
-
-    if ((flags & ~rand_drbg_used_flags) != 0) {
-        RANDerr(RAND_F_RAND_DRBG_SET_DEFAULTS, RAND_R_UNSUPPORTED_DRBG_FLAGS);
-        return 0;
-    }
-
-    all = ((flags & RAND_DRBG_TYPE_FLAGS) == 0);
-    if (all || (flags & RAND_DRBG_FLAG_PRIMARY) != 0) {
-        rand_drbg_type[RAND_DRBG_TYPE_PRIMARY] = type;
-        rand_drbg_flags[RAND_DRBG_TYPE_PRIMARY] = flags
-                                                  | RAND_DRBG_FLAG_PRIMARY;
-    }
-    if (all || (flags & RAND_DRBG_FLAG_PUBLIC) != 0) {
-        rand_drbg_type[RAND_DRBG_TYPE_PUBLIC]  = type;
-        rand_drbg_flags[RAND_DRBG_TYPE_PUBLIC] = flags | RAND_DRBG_FLAG_PUBLIC;
-    }
-    if (all || (flags & RAND_DRBG_FLAG_PRIVATE) != 0) {
-        rand_drbg_type[RAND_DRBG_TYPE_PRIVATE] = type;
-        rand_drbg_flags[RAND_DRBG_TYPE_PRIVATE] = flags
-                                                  | RAND_DRBG_FLAG_PRIVATE;
-    }
-    return 1;
-}
-
-
-/*
- * Allocate memory and initialize a new DRBG.
- * The |parent|, if not NULL, will be used as random source for reseeding.
- *
- * Returns a pointer to the new DRBG instance on success, NULL on failure.
- */
-static RAND_DRBG *rand_drbg_new(OPENSSL_CTX *ctx,
-                                int type,
-                                unsigned int flags,
-                                RAND_DRBG *parent)
-{
-    RAND_DRBG *drbg = OPENSSL_zalloc(sizeof(*drbg));
-
-    if (drbg == NULL) {
-        RANDerr(RAND_F_RAND_DRBG_NEW, ERR_R_MALLOC_FAILURE);
-        return NULL;
-    }
-
-    drbg->libctx = ctx;
-    drbg->parent = parent;
-
-    if (RAND_DRBG_set(drbg, type, flags) == 0)
-        goto err;
-
-    return drbg;
-
- err:
-    RAND_DRBG_free(drbg);
-
-    return NULL;
-}
-
-RAND_DRBG *RAND_DRBG_new_ex(OPENSSL_CTX *ctx, int type, unsigned int flags,
-                            RAND_DRBG *parent)
-{
-    return rand_drbg_new(ctx, type, flags, parent);
-}
-
-RAND_DRBG *RAND_DRBG_new(int type, unsigned int flags, RAND_DRBG *parent)
-{
-    return RAND_DRBG_new_ex(NULL, type, flags, parent);
-}
-
-/*
- * Uninstantiate |drbg| and free all memory.
- */
-void RAND_DRBG_free(RAND_DRBG *drbg)
-{
-    if (drbg == NULL)
-        return;
-
-    CRYPTO_free_ex_data(CRYPTO_EX_INDEX_RAND_DRBG, drbg, &drbg->ex_data);
-    EVP_RAND_CTX_free(drbg->rand);
-    OPENSSL_free(drbg);
-}
-
-/*
- * Instantiate |drbg|, after it has been initialized.  Use |pers| and
- * |perslen| as prediction-resistance input.
- *
- * Requires that drbg->lock is already locked for write, if non-null.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_instantiate(RAND_DRBG *drbg,
-                          const unsigned char *pers, size_t perslen)
-{
-    return EVP_RAND_instantiate(drbg->rand, EVP_RAND_strength(drbg->rand), 0,
-                                pers, perslen);
-}
-
-/*
- * Uninstantiate |drbg|. Must be instantiated before it can be used.
- *
- * Requires that drbg->lock is already locked for write, if non-null.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_uninstantiate(RAND_DRBG *drbg)
-{
-    int index = -1, type, flags;
-
-    if (!EVP_RAND_uninstantiate(drbg->rand))
-        return 0;
-
-    /* The reset uses the default values for type and flags */
-    if (drbg->flags & RAND_DRBG_FLAG_PRIMARY)
-        index = RAND_DRBG_TYPE_PRIMARY;
-    else if (drbg->flags & RAND_DRBG_FLAG_PRIVATE)
-        index = RAND_DRBG_TYPE_PRIVATE;
-    else if (drbg->flags & RAND_DRBG_FLAG_PUBLIC)
-        index = RAND_DRBG_TYPE_PUBLIC;
-
-    if (index != -1) {
-        flags = rand_drbg_flags[index];
-        type = rand_drbg_type[index];
-    } else {
-        flags = drbg->flags;
-        type = drbg->type;
-    }
-    return RAND_DRBG_set(drbg, type, flags);
-}
-
-/*
- * Reseed |drbg|, mixing in the specified data
- *
- * Requires that drbg->lock is already locked for write, if non-null.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_reseed(RAND_DRBG *drbg,
-                     const unsigned char *adin, size_t adinlen,
-                     int prediction_resistance)
-{
-    return EVP_RAND_reseed(drbg->rand, prediction_resistance, NULL, 0,
-                           adin, adinlen);
-}
-
-/*
- * Generate |outlen| bytes into the buffer at |out|.  Reseed if we need
- * to or if |prediction_resistance| is set.  Additional input can be
- * sent in |adin| and |adinlen|.
- *
- * Requires that drbg->lock is already locked for write, if non-null.
- *
- * Returns 1 on success, 0 on failure.
- *
- */
-int RAND_DRBG_generate(RAND_DRBG *drbg, unsigned char *out, size_t outlen,
-                       int prediction_resistance,
-                       const unsigned char *adin, size_t adinlen)
-{
-    return EVP_RAND_generate(drbg->rand, out, outlen, 0,
-                             prediction_resistance, adin, adinlen);
-}
-
-/*
- * Generates |outlen| random bytes and stores them in |out|. It will
- * using the given |drbg| to generate the bytes.
- *
- * Requires that drbg->lock is already locked for write, if non-null.
- *
- * Returns 1 on success 0 on failure.
- */
-int RAND_DRBG_bytes(RAND_DRBG *drbg, unsigned char *out, size_t outlen)
-{
-    return EVP_RAND_generate(drbg->rand, out, outlen, 0, 0, NULL, 0);
-}
-
-/* DRBG call back shims */
-static int rand_drbg_get_entroy_cb(const OSSL_PARAM *params, OSSL_PARAM *out,
-                                   void *vdrbg)
-{
-    RAND_DRBG *drbg = (RAND_DRBG *)vdrbg;
-    int entropy = 0, prediction_resistance = 0;
-    size_t min_len = 0, max_len = 2048;
-    const OSSL_PARAM *p;
-    OSSL_PARAM *q;
-
-    if (drbg->get_entropy == NULL)
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_ENTROPY_REQUIRED);
-    if (p == NULL || !OSSL_PARAM_get_int(p, &entropy))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_PREDICTION_RESISTANCE);
-    if (p == NULL || !OSSL_PARAM_get_int(p, &prediction_resistance))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_MAX_LENGTH);
-    if (p == NULL || !OSSL_PARAM_get_size_t(p, &max_len))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_MIN_LENGTH);
-    if (p == NULL || !OSSL_PARAM_get_size_t(p, &min_len))
-        return 0;
-
-    q = OSSL_PARAM_locate(out, OSSL_DRBG_PARAM_RANDOM_DATA);
-    if (q == NULL || q->data_type != OSSL_PARAM_OCTET_PTR || q->data == NULL)
-        return 0;
-
-    q->return_size = drbg->get_entropy(drbg, (unsigned char **)q->data, entropy,
-                                       min_len, max_len, prediction_resistance);
-    return 1;
-}
-
-static int rand_drbg_cleanup_entropy_cb(const OSSL_PARAM *params, void *vdrbg)
-{
-    RAND_DRBG *drbg = (RAND_DRBG *)vdrbg;
-    const OSSL_PARAM *p;
-    size_t sz;
-
-    if (drbg->cleanup_entropy == NULL)
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_SIZE);
-    if (p == NULL || !OSSL_PARAM_get_size_t(p, &sz))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_RANDOM_DATA);
-    if (p == NULL || p->data_type != OSSL_PARAM_OCTET_PTR)
-        return 0;
-
-    drbg->cleanup_entropy(drbg, p->data, sz);
-    return 1;
-}
-
-static int rand_drbg_get_nonce_cb(const OSSL_PARAM *params, OSSL_PARAM *out,
-                                  void *vdrbg)
-{
-    RAND_DRBG *drbg = (RAND_DRBG *)vdrbg;
-    int entropy = 0;
-    size_t min_len = 0, max_len = 10240;
-    const OSSL_PARAM *p;
-    OSSL_PARAM *q;
-
-    if (drbg->get_nonce == NULL)
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_ENTROPY_REQUIRED);
-    if (p == NULL || !OSSL_PARAM_get_int(p, &entropy))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_MAX_LENGTH);
-    if (p == NULL || !OSSL_PARAM_get_size_t(p, &max_len))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_MIN_LENGTH);
-    if (p == NULL || !OSSL_PARAM_get_size_t(p, &min_len))
-        return 0;
-
-    q = OSSL_PARAM_locate(out, OSSL_DRBG_PARAM_RANDOM_DATA);
-    if (q == NULL || q->data_type != OSSL_PARAM_OCTET_PTR || q->data == NULL)
-        return 0;
-
-    q->return_size = drbg->get_nonce(drbg, (unsigned char **)q->data, entropy,
-                                     min_len, max_len);
-    return 1;
-}
-
-static int rand_drbg_cleanup_nonce_cb(const OSSL_PARAM *params, void *vdrbg)
-{
-    RAND_DRBG *drbg = (RAND_DRBG *)vdrbg;
-    const OSSL_PARAM *p;
-    size_t sz;
-
-    if (drbg->cleanup_nonce == NULL)
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_SIZE);
-    if (p == NULL || !OSSL_PARAM_get_size_t(p, &sz))
-        return 0;
-
-    p = OSSL_PARAM_locate_const(params, OSSL_DRBG_PARAM_RANDOM_DATA);
-    if (p == NULL || p->data_type != OSSL_PARAM_OCTET_PTR)
-        return 0;
-
-    drbg->cleanup_nonce(drbg, p->data, sz);
-    return 1;
-}
-
-/*
- * Set the RAND_DRBG callbacks for obtaining entropy and nonce.
- *
- * Setting the callbacks is allowed only if the drbg has not been
- * initialized yet. Otherwise, the operation will fail.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_set_callbacks(RAND_DRBG *drbg,
-                            RAND_DRBG_get_entropy_fn get_entropy,
-                            RAND_DRBG_cleanup_entropy_fn cleanup_entropy,
-                            RAND_DRBG_get_nonce_fn get_nonce,
-                            RAND_DRBG_cleanup_nonce_fn cleanup_nonce)
-{
-    EVP_RAND_CTX *rand = drbg->rand;
-    OSSL_INOUT_CALLBACK *g_ent = NULL, *g_nonce = NULL;
-    OSSL_CALLBACK *c_ent = NULL, *c_nonce = NULL;
-
-    if (get_entropy != NULL) {
-        g_ent = &rand_drbg_get_entroy_cb;
-        c_ent = &rand_drbg_cleanup_entropy_cb;
-    }
-    if (get_nonce != NULL) {
-        g_nonce = rand_drbg_get_nonce_cb;
-        c_nonce = rand_drbg_cleanup_nonce_cb;
-    }
-    if (!EVP_RAND_set_callbacks(rand, g_ent, c_ent, g_nonce, c_nonce, drbg))
-        return 0;
-
-    drbg->get_entropy = g_ent != NULL ? get_entropy : NULL;
-    drbg->cleanup_entropy = c_ent != NULL ? cleanup_entropy : NULL;
-    drbg->get_nonce = g_nonce != NULL ? get_nonce : NULL;
-    drbg->cleanup_nonce = c_nonce != NULL ? cleanup_nonce : NULL;
-    return 1;
-}
-
-/*
- * Set the reseed interval.
- *
- * The drbg will reseed automatically whenever the number of generate
- * requests exceeds the given reseed interval. If the reseed interval
- * is 0, then this feature is disabled.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_set_reseed_interval(RAND_DRBG *drbg, unsigned int interval)
-{
-    OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
-
-    if (interval > MAX_RESEED_INTERVAL)
-        return 0;
-    params[0] = OSSL_PARAM_construct_uint(OSSL_DRBG_PARAM_RESEED_REQUESTS,
-                                          &interval);
-    return EVP_RAND_set_ctx_params(drbg->rand, params);
-}
-
-/*
- * Set the reseed time interval.
- *
- * The drbg will reseed automatically whenever the time elapsed since
- * the last reseeding exceeds the given reseed time interval. For safety,
- * a reseeding will also occur if the clock has been reset to a smaller
- * value.
- *
- * Returns 1 on success, 0 on failure.
- */
-int RAND_DRBG_set_reseed_time_interval(RAND_DRBG *drbg, time_t interval)
-{
-    OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
-
-    if (interval > MAX_RESEED_TIME_INTERVAL)
-        return 0;
-    params[0] =
-        OSSL_PARAM_construct_time_t(OSSL_DRBG_PARAM_RESEED_TIME_INTERVAL,
-                                    &interval);
-    return EVP_RAND_set_ctx_params(drbg->rand, params);
-}
-
-/*
- * Set the default values for reseed (time) intervals of new DRBG instances
- *
- * The default values can be set independently for primary DRBG instances
- * (without a parent) and secondary DRBG instances (with parent).
- *
- * Returns 1 on success, 0 on failure.
- */
-
-int RAND_DRBG_set_reseed_defaults(
-                                  unsigned int _primary_reseed_interval,
-                                  unsigned int _secondary_reseed_interval,
-                                  time_t _primary_reseed_time_interval,
-                                  time_t _secondary_reseed_time_interval
-                                  )
-{
-    if (_primary_reseed_interval > MAX_RESEED_INTERVAL
-        || _secondary_reseed_interval > MAX_RESEED_INTERVAL)
-        return 0;
-
-    if (_primary_reseed_time_interval > MAX_RESEED_TIME_INTERVAL
-        || _secondary_reseed_time_interval > MAX_RESEED_TIME_INTERVAL)
-        return 0;
-
-    primary_reseed_interval = _primary_reseed_interval;
-    secondary_reseed_interval = _secondary_reseed_interval;
-
-    primary_reseed_time_interval = _primary_reseed_time_interval;
-    secondary_reseed_time_interval = _secondary_reseed_time_interval;
-
-    return 1;
-}
-
-/*
- * Get and set the EXDATA
- */
-int RAND_DRBG_set_ex_data(RAND_DRBG *drbg, int idx, void *arg)
-{
-    return CRYPTO_set_ex_data(&drbg->ex_data, idx, arg);
-}
-
-void *RAND_DRBG_get_ex_data(const RAND_DRBG *drbg, int idx)
-{
-    return CRYPTO_get_ex_data(&drbg->ex_data, idx);
-}
-
-/*
- * The following functions provide a RAND_METHOD that works on the
- * global DRBG.  They lock.
- */
-
-/*
- * Allocates a new global DRBG on the secure heap (if enabled) and
- * initializes it with default settings.
- *
- * Returns a pointer to the new DRBG instance on success, NULL on failure.
- */
-static RAND_DRBG *drbg_setup(OPENSSL_CTX *ctx, RAND_DRBG *parent, int drbg_type)
-{
-    RAND_DRBG *drbg;
-
-    drbg = RAND_DRBG_new_ex(ctx, rand_drbg_type[drbg_type],
-                            rand_drbg_flags[drbg_type], parent);
-    if (drbg == NULL)
-        return NULL;
-
-    /* Only the primary DRBG needs to have a lock */
-    if (parent == NULL && EVP_RAND_enable_locking(drbg->rand) == 0)
-        goto err;
-
-    /*
-     * Ignore instantiation error to support just-in-time instantiation.
-     *
-     * The state of the drbg will be checked in RAND_DRBG_generate() and
-     * an automatic recovery is attempted.
-     */
-    (void)RAND_DRBG_instantiate(drbg, NULL, 0);
-    return drbg;
-
-err:
-    RAND_DRBG_free(drbg);
-    return NULL;
-}
-
-static void drbg_delete_thread_state(void *arg)
-{
-    OPENSSL_CTX *ctx = arg;
-    DRBG_GLOBAL *dgbl = drbg_get_global(ctx);
-    RAND_DRBG *drbg;
-
-    if (dgbl == NULL)
-        return;
-    drbg = CRYPTO_THREAD_get_local(&dgbl->public_drbg);
-    CRYPTO_THREAD_set_local(&dgbl->public_drbg, NULL);
-    RAND_DRBG_free(drbg);
-
-    drbg = CRYPTO_THREAD_get_local(&dgbl->private_drbg);
-    CRYPTO_THREAD_set_local(&dgbl->private_drbg, NULL);
-    RAND_DRBG_free(drbg);
-}
-
-/* Implements the default OpenSSL RAND_bytes() method */
-static int drbg_bytes(unsigned char *out, int count)
-{
-    int ret;
-    RAND_DRBG *drbg = RAND_DRBG_get0_public();
-
-    if (drbg == NULL)
-        return 0;
-
-    ret = RAND_DRBG_bytes(drbg, out, count);
-
-    return ret;
-}
-
-/* Implements the default OpenSSL RAND_add() method */
-static int drbg_add(const void *buf, int num, double randomness)
-{
-    RAND_DRBG *drbg = RAND_DRBG_get0_master();
-
-    if (drbg == NULL || num <= 0)
-        return 0;
-
-    return EVP_RAND_reseed(drbg->rand, 0, NULL, 0, buf, num);
-}
-
-/* Implements the default OpenSSL RAND_seed() method */
-static int drbg_seed(const void *buf, int num)
-{
-    return drbg_add(buf, num, num);
-}
-
-/* Implements the default OpenSSL RAND_status() method */
-static int drbg_status(void)
-{
-    int ret;
-    RAND_DRBG *drbg = RAND_DRBG_get0_master();
-
-    if (drbg == NULL)
-        return 0;
-
-    ret = EVP_RAND_state(drbg->rand) == EVP_RAND_STATE_READY ? 1 : 0;
-    return ret;
-}
-
-int RAND_DRBG_verify_zeroization(RAND_DRBG *drbg)
-{
-    return EVP_RAND_verify_zeroization(drbg->rand);
-}
-
-/*
- * Get the primary DRBG.
- * Returns pointer to the DRBG on success, NULL on failure.
- *
- */
-RAND_DRBG *OPENSSL_CTX_get0_primary_drbg(OPENSSL_CTX *ctx)
-{
-    DRBG_GLOBAL *dgbl = drbg_get_global(ctx);
-
-    if (dgbl == NULL)
-        return NULL;
-
-    if (dgbl->primary_drbg == NULL) {
-        if (!CRYPTO_THREAD_write_lock(dgbl->lock))
-            return NULL;
-        if (dgbl->primary_drbg == NULL)
-            dgbl->primary_drbg = drbg_setup(ctx, NULL, RAND_DRBG_TYPE_PRIMARY);
-        CRYPTO_THREAD_unlock(dgbl->lock);
-    }
-    return dgbl->primary_drbg;
-}
-
-RAND_DRBG *RAND_DRBG_get0_master(void)
-{
-    return OPENSSL_CTX_get0_primary_drbg(NULL);
-}
-
-/*
- * Get the public DRBG.
- * Returns pointer to the DRBG on success, NULL on failure.
- */
-RAND_DRBG *OPENSSL_CTX_get0_public_drbg(OPENSSL_CTX *ctx)
-{
-    DRBG_GLOBAL *dgbl = drbg_get_global(ctx);
-    RAND_DRBG *drbg, *primary;
-
-    if (dgbl == NULL)
-        return NULL;
-
-    drbg = CRYPTO_THREAD_get_local(&dgbl->public_drbg);
-    if (drbg == NULL) {
-        primary = OPENSSL_CTX_get0_primary_drbg(ctx);
-        if (primary == NULL)
-            return NULL;
-
-        ctx = openssl_ctx_get_concrete(ctx);
-        /*
-         * If the private_drbg is also NULL then this is the first time we've
-         * used this thread.
-         */
-        if (CRYPTO_THREAD_get_local(&dgbl->private_drbg) == NULL
-                && !ossl_init_thread_start(NULL, ctx, drbg_delete_thread_state))
-            return NULL;
-        drbg = drbg_setup(ctx, primary, RAND_DRBG_TYPE_PUBLIC);
-        CRYPTO_THREAD_set_local(&dgbl->public_drbg, drbg);
-    }
-    return drbg;
-}
-
-RAND_DRBG *RAND_DRBG_get0_public(void)
-{
-    return OPENSSL_CTX_get0_public_drbg(NULL);
-}
-
-/*
- * Get the private DRBG.
- * Returns pointer to the DRBG on success, NULL on failure.
- */
-RAND_DRBG *OPENSSL_CTX_get0_private_drbg(OPENSSL_CTX *ctx)
-{
-    DRBG_GLOBAL *dgbl = drbg_get_global(ctx);
-    RAND_DRBG *drbg, *primary;
-
-    if (dgbl == NULL)
-        return NULL;
-
-    drbg = CRYPTO_THREAD_get_local(&dgbl->private_drbg);
-    if (drbg == NULL) {
-        primary = OPENSSL_CTX_get0_primary_drbg(ctx);
-        if (primary == NULL)
-            return NULL;
-
-        ctx = openssl_ctx_get_concrete(ctx);
-        /*
-         * If the public_drbg is also NULL then this is the first time we've
-         * used this thread.
-         */
-        if (CRYPTO_THR