/src/openssl/providers/implementations/rands/drbg_hmac.c

Source
/*
 * Copyright 2011-2025 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
 */

#include <stdlib.h>
#include <string.h>
#include <openssl/crypto.h>
#include <openssl/err.h>
#include <openssl/rand.h>
#include <openssl/proverr.h>
#include "internal/cryptlib.h"
#include "internal/thread_once.h"
#include "prov/providercommon.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "prov/hmac_drbg.h"
#include "prov/drbg.h"
#include "crypto/evp.h"
#include "crypto/evp/evp_local.h"
#include "internal/provider.h"

#define drbg_hmac_get_ctx_params_st  drbg_get_ctx_params_st
#define drbg_hmac_set_ctx_params_st  drbg_set_ctx_params_st

#include "providers/implementations/rands/drbg_hmac.inc"

static OSSL_FUNC_rand_newctx_fn drbg_hmac_new_wrapper;
static OSSL_FUNC_rand_freectx_fn drbg_hmac_free;
static OSSL_FUNC_rand_instantiate_fn drbg_hmac_instantiate_wrapper;
static OSSL_FUNC_rand_uninstantiate_fn drbg_hmac_uninstantiate_wrapper;
static OSSL_FUNC_rand_generate_fn drbg_hmac_generate_wrapper;
static OSSL_FUNC_rand_reseed_fn drbg_hmac_reseed_wrapper;
static OSSL_FUNC_rand_settable_ctx_params_fn drbg_hmac_settable_ctx_params;
static OSSL_FUNC_rand_set_ctx_params_fn drbg_hmac_set_ctx_params;
static OSSL_FUNC_rand_gettable_ctx_params_fn drbg_hmac_gettable_ctx_params;
static OSSL_FUNC_rand_get_ctx_params_fn drbg_hmac_get_ctx_params;
static OSSL_FUNC_rand_verify_zeroization_fn drbg_hmac_verify_zeroization;

static int drbg_hmac_set_ctx_params_locked(PROV_DRBG *drbg,
                                           const struct drbg_set_ctx_params_st *p);

/*
 * Called twice by SP800-90Ar1 10.1.2.2 HMAC_DRBG_Update_Process.
 *
 * hmac is an object that holds the input/output Key and Value (K and V).
 * inbyte is 0x00 on the first call and 0x01 on the second call.
 * in1, in2, in3 are optional inputs that can be NULL.
 * in1len, in2len, in3len are the lengths of the input buffers.
 *
 * The returned K,V is:
 *   hmac->K = HMAC(hmac->K, hmac->V || inbyte || [in1] || [in2] || [in3])
 *   hmac->V = HMAC(hmac->K, hmac->V)
 *
 * Returns zero if an error occurs otherwise it returns 1.
 */
static int do_hmac(PROV_DRBG_HMAC *hmac, unsigned char inbyte,
                   const unsigned char *in1, size_t in1len,
                   const unsigned char *in2, size_t in2len,
                   const unsigned char *in3, size_t in3len)
{
    EVP_MAC_CTX *ctx = hmac->ctx;

    if (!EVP_MAC_init(ctx, hmac->K, hmac->blocklen, NULL)
            /* K = HMAC(K, V || inbyte || [in1] || [in2] || [in3]) */
            || !EVP_MAC_update(ctx, hmac->V, hmac->blocklen)
            || !EVP_MAC_update(ctx, &inbyte, 1)
            || !(in1 == NULL || in1len == 0 || EVP_MAC_update(ctx, in1, in1len))
            || !(in2 == NULL || in2len == 0 || EVP_MAC_update(ctx, in2, in2len))
            || !(in3 == NULL || in3len == 0 || EVP_MAC_update(ctx, in3, in3len))
            || !EVP_MAC_final(ctx, hmac->K, NULL, sizeof(hmac->K)))
        return 0;

   /* V = HMAC(K, V) */
    return EVP_MAC_init(ctx, hmac->K, hmac->blocklen, NULL)
           && EVP_MAC_update(ctx, hmac->V, hmac->blocklen)
           && EVP_MAC_final(ctx, hmac->V, NULL, sizeof(hmac->V));
}

/*
 * SP800-90Ar1 10.1.2.2 HMAC_DRBG_Update_Process
 *
 *
 * Updates the drbg objects Key(K) and Value(V) using the following algorithm:
 *   K,V = do_hmac(hmac, 0, in1, in2, in3)
 *   if (any input is not NULL)
 *     K,V = do_hmac(hmac, 1, in1, in2, in3)
 *
 * where in1, in2, in3 are optional input buffers that can be NULL.
 *       in1len, in2len, in3len are the lengths of the input buffers.
 *
 * Returns zero if an error occurs otherwise it returns 1.
 */
static int drbg_hmac_update(PROV_DRBG_HMAC *hmac,
                            const unsigned char *in1, size_t in1len,
                            const unsigned char *in2, size_t in2len,
                            const unsigned char *in3, size_t in3len)
{
    /* (Steps 1-2) K = HMAC(K, V||0x00||provided_data). V = HMAC(K,V) */
    if (!do_hmac(hmac, 0x00, in1, in1len, in2, in2len, in3, in3len))
        return 0;
    /* (Step 3) If provided_data == NULL then return (K,V) */
    if (in1len == 0 && in2len == 0 && in3len == 0)
        return 1;
    /* (Steps 4-5) K = HMAC(K, V||0x01||provided_data). V = HMAC(K,V) */
    return do_hmac(hmac, 0x01, in1, in1len, in2, in2len, in3, in3len);
}

/*
 * SP800-90Ar1 10.1.2.3 HMAC_DRBG_Instantiate_Process:
 *
 * This sets the drbg Key (K) to all zeros, and Value (V) to all 1's.
 * and then calls (K,V) = drbg_hmac_update() with input parameters:
 *   ent = entropy data (Can be NULL) of length ent_len.
 *   nonce = nonce data (Can be NULL) of length nonce_len.
 *   pstr = personalization data (Can be NULL) of length pstr_len.
 *
 * Returns zero if an error occurs otherwise it returns 1.
 */
int ossl_drbg_hmac_init(PROV_DRBG_HMAC *hmac,
                        const unsigned char *ent, size_t ent_len,
                        const unsigned char *nonce, size_t nonce_len,
                        const unsigned char *pstr, size_t pstr_len)
{
    if (hmac->ctx == NULL) {
        ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MAC);
        return 0;
    }

    /* (Step 2) Key = 0x00 00...00 */
    memset(hmac->K, 0x00, hmac->blocklen);
    /* (Step 3) V = 0x01 01...01 */
    memset(hmac->V, 0x01, hmac->blocklen);
    /* (Step 4) (K,V) = HMAC_DRBG_Update(entropy||nonce||pers string, K, V) */
    return drbg_hmac_update(hmac, ent, ent_len, nonce, nonce_len, pstr,
                            pstr_len);
}
static int drbg_hmac_instantiate(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)
{
    return ossl_drbg_hmac_init((PROV_DRBG_HMAC *)drbg->data, ent, ent_len,
                               nonce, nonce_len, pstr, pstr_len);
}

static int drbg_hmac_instantiate_wrapper(void *vdrbg, unsigned int strength,
                                         int prediction_resistance,
                                         const unsigned char *pstr,
                                         size_t pstr_len,
                                         const OSSL_PARAM params[])
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    struct drbg_set_ctx_params_st p;
    int ret = 0;

    if (drbg == NULL || !drbg_hmac_set_ctx_params_decoder(params, &p))
        return 0;

    if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
        return 0;

    if (!ossl_prov_is_running()
            || !drbg_hmac_set_ctx_params_locked(drbg, &p))
        goto err;
    ret = ossl_prov_drbg_instantiate(drbg, strength, prediction_resistance,
                                     pstr, pstr_len);
 err:
    if (drbg->lock != NULL)
        CRYPTO_THREAD_unlock(drbg->lock);
    return ret;
}

/*
 * SP800-90Ar1 10.1.2.4 HMAC_DRBG_Reseed_Process:
 *
 * Reseeds the drbg's Key (K) and Value (V) by calling
 * (K,V) = drbg_hmac_update() with the following input parameters:
 *   ent = entropy input data (Can be NULL) of length ent_len.
 *   adin = additional input data (Can be NULL) of length adin_len.
 *
 * Returns zero if an error occurs otherwise it returns 1.
 */
static int drbg_hmac_reseed(PROV_DRBG *drbg,
                            const unsigned char *ent, size_t ent_len,
                            const unsigned char *adin, size_t adin_len)
{
    PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)drbg->data;

    /* (Step 2) (K,V) = HMAC_DRBG_Update(entropy||additional_input, K, V) */
    return drbg_hmac_update(hmac, ent, ent_len, adin, adin_len, NULL, 0);
}

static int drbg_hmac_reseed_wrapper(void *vdrbg, int prediction_resistance,
                                    const unsigned char *ent, size_t ent_len,
                                    const unsigned char *adin, size_t adin_len)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;

    return ossl_prov_drbg_reseed(drbg, prediction_resistance, ent, ent_len,
                                 adin, adin_len);
}

/*
 * SP800-90Ar1 10.1.2.5 HMAC_DRBG_Generate_Process:
 *
 * Generates pseudo random bytes and updates the internal K,V for the drbg.
 * out is a buffer to fill with outlen bytes of pseudo random data.
 * adin is an additional_input string of size adin_len that may be NULL.
 *
 * Returns zero if an error occurs otherwise it returns 1.
 */
int ossl_drbg_hmac_generate(PROV_DRBG_HMAC *hmac,
                            unsigned char *out, size_t outlen,
                            const unsigned char *adin, size_t adin_len)
{
    EVP_MAC_CTX *ctx = hmac->ctx;
    const unsigned char *temp = hmac->V;

    /* (Step 2) if adin != NULL then (K,V) = HMAC_DRBG_Update(adin, K, V) */
    if (adin != NULL
            && adin_len > 0
            && !drbg_hmac_update(hmac, adin, adin_len, NULL, 0, NULL, 0))
        return 0;

    /*
     * (Steps 3-5) temp = NULL
     *             while (len(temp) < outlen) {
     *                 V = HMAC(K, V)
     *                 temp = temp || V
     *             }
     */
    for (;;) {
        if (!EVP_MAC_init(ctx, hmac->K, hmac->blocklen, NULL)
            || !EVP_MAC_update(ctx, temp, hmac->blocklen))
            return 0;

        if (outlen > hmac->blocklen) {
            if (!EVP_MAC_final(ctx, out, NULL, outlen))
                return 0;
            temp = out;
        } else {
            if (!EVP_MAC_final(ctx, hmac->V, NULL, sizeof(hmac->V)))
                return 0;
            memcpy(out, hmac->V, outlen);
            break;
        }
        out += hmac->blocklen;
        outlen -= hmac->blocklen;
    }
    /* (Step 6) (K,V) = HMAC_DRBG_Update(adin, K, V) */
    if (!drbg_hmac_update(hmac, adin, adin_len, NULL, 0, NULL, 0))
        return 0;

    return 1;
}

static int drbg_hmac_generate(PROV_DRBG *drbg,
                              unsigned char *out, size_t outlen,
                              const unsigned char *adin, size_t adin_len)
{
    return ossl_drbg_hmac_generate((PROV_DRBG_HMAC *)drbg->data, out, outlen,
                                    adin, adin_len);
}

static int drbg_hmac_generate_wrapper(void *vdrbg,
     unsigned char *out, size_t outlen, unsigned int strength,
     int prediction_resistance, const unsigned char *adin, size_t adin_len)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;

    return ossl_prov_drbg_generate(drbg, out, outlen, strength,
                                   prediction_resistance, adin, adin_len);
}

static int drbg_hmac_uninstantiate(PROV_DRBG *drbg)
{
    PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)drbg->data;

    OPENSSL_cleanse(hmac->K, sizeof(hmac->K));
    OPENSSL_cleanse(hmac->V, sizeof(hmac->V));
    return ossl_prov_drbg_uninstantiate(drbg);
}

static int drbg_hmac_uninstantiate_wrapper(void *vdrbg)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    int ret;

    if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
        return 0;

    ret = drbg_hmac_uninstantiate(drbg);

    if (drbg->lock != NULL)
        CRYPTO_THREAD_unlock(drbg->lock);

    return ret;
}

static int drbg_hmac_verify_zeroization(void *vdrbg)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)drbg->data;
    int ret = 0;

    if (drbg->lock != NULL && !CRYPTO_THREAD_read_lock(drbg->lock))
        return 0;

    PROV_DRBG_VERIFY_ZEROIZATION(hmac->K);
    PROV_DRBG_VERIFY_ZEROIZATION(hmac->V);

    ret = 1;
 err:
    if (drbg->lock != NULL)
        CRYPTO_THREAD_unlock(drbg->lock);
    return ret;
}

static int drbg_hmac_new(PROV_DRBG *drbg)
{
    PROV_DRBG_HMAC *hmac;

    hmac = OPENSSL_secure_zalloc(sizeof(*hmac));
    if (hmac == NULL)
        return 0;

    OSSL_FIPS_IND_INIT(drbg)

    drbg->data = hmac;
    /* See SP800-57 Part1 Rev4 5.6.1 Table 3 */
    drbg->max_entropylen = DRBG_MAX_LENGTH;
    drbg->max_noncelen = DRBG_MAX_LENGTH;
    drbg->max_perslen = DRBG_MAX_LENGTH;
    drbg->max_adinlen = DRBG_MAX_LENGTH;

    /* Maximum number of bits per request = 2^19  = 2^16 bytes */
    drbg->max_request = 1 << 16;
    return 1;
}

static void *drbg_hmac_new_wrapper(void *provctx, void *parent,
                                   const OSSL_DISPATCH *parent_dispatch)
{
    return ossl_rand_drbg_new(provctx, parent, parent_dispatch,
                              &drbg_hmac_new, &drbg_hmac_free,
                              &drbg_hmac_instantiate, &drbg_hmac_uninstantiate,
                              &drbg_hmac_reseed, &drbg_hmac_generate);
}

static void drbg_hmac_free(void *vdrbg)
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    PROV_DRBG_HMAC *hmac;

    if (drbg != NULL && (hmac = (PROV_DRBG_HMAC *)drbg->data) != NULL) {
        EVP_MAC_CTX_free(hmac->ctx);
        ossl_prov_digest_reset(&hmac->digest);
        OPENSSL_secure_clear_free(hmac, sizeof(*hmac));
    }
    ossl_rand_drbg_free(drbg);
}

static int drbg_hmac_get_ctx_params(void *vdrbg, OSSL_PARAM params[])
{
    PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
    PROV_DRBG_HMAC *hmac;
    const EVP_MD *md;
    struct drbg_get_ctx_params_st p;
    int ret = 0, complete = 0;

    if (drbg == NULL || !drbg_hmac_get_ctx_params_decoder(params, &p))
        return 0;

    if (!ossl_drbg_get_ctx_params_no_lock(drbg, &p, params, &complete))
        return 0;

    if (complete)
        return 1;

    hmac = (PROV_DRBG_HMAC *)drbg->data;

    if (drbg->lock != NULL && !CRYPTO_THREAD_read_lock(drbg->lock))
        return 0;

    if (p.digest != NULL) {
        md = ossl_prov_digest_md(&hmac->digest);
        if (md == NULL
                || !OSSL_PARAM_set_utf8_string(p.digest, EVP_MD_get0_name(md)))
            goto err;
    }

    ret = ossl_drbg_get_ctx_params(drbg, &p);
 err:
    if (drbg->lock != NULL)
        CRYPTO_THREAD_unlock(drbg->lock);

    return ret;
}

static const OSSL_PARAM *drbg_hmac_gettable_ctx_params(ossl_unused void *vctx,
                                                       ossl_unused void *p_ctx)
{
    return drbg_hmac_get_ctx_params_list;
}

static int drbg_fetch_algs_from_prov(const struct drbg_set_ctx_params_st *p,
                                     OSSL_LIB_CTX *libctx,
                                     EVP_MAC_CTX **macctx,
                                     EVP_MD **digest)
{
    OSSL_PROVIDER *prov = NULL;
    EVP_MD *md = NULL;
    int ret = 0;

    if (macctx == NULL || digest == NULL)
        return 0;

    if (p->prov == NULL || p->prov->data_type != OSSL_PARAM_UTF8_STRING)
        return 0;
    if ((prov = ossl_provider_find(libctx, (const char *)p->prov->data, 1)) == NULL)
        return 0;

    if (p->digest != NULL) {
        if (p->digest->data_type != OSSL_PARAM_UTF8_STRING)
            goto done;

        md = evp_digest_fetch_from_prov(prov, (const char *)p->digest->data, NULL);
        if (md) {
            EVP_MD_free(*digest);
            *digest = md;
        } else {
            goto done;
        }
    }

    ret = 1;

done:
    ossl_provider_free(prov);
    return ret;
}

static int drbg_hmac_set_ctx_params_locked
        (PROV_DRBG *ctx, const struct drbg_set_ctx_params_st *p)
{
    PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)ctx->data;
    OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
    EVP_MD *prov_md = NULL;
    const EVP_MD *md;
    int md_size;

    if (!OSSL_FIPS_IND_SET_CTX_FROM_PARAM(ctx, OSSL_FIPS_IND_SETTABLE0, p->ind_d))
        return 0;

    /* try to fetch mac and digest from provider */
    (void)ERR_set_mark();
    if (!drbg_fetch_algs_from_prov(p, libctx, &hmac->ctx, &prov_md)) {
        (void)ERR_pop_to_mark();
        if (p->digest != NULL) {
            /* fall back to full implementation search */
            if (!ossl_prov_digest_load(&hmac->digest, p->digest, p->propq,
                                       p->engine, libctx))
                return 0;

            if (!ossl_prov_macctx_load(&hmac->ctx, NULL, NULL, p->digest,
                                       p->propq, p->engine,
                                       "HMAC", NULL, NULL, libctx))
                return 0;
        }
    } else {
        (void)ERR_clear_last_mark();
        if (prov_md)
            ossl_prov_digest_set_md(&hmac->digest, prov_md);
    }

    md = ossl_prov_digest_md(&hmac->digest);
    if (md != NULL && !ossl_drbg_verify_digest(ctx, libctx, md))
        return 0;   /* Error already raised for us */

    if (md != NULL && hmac->ctx != NULL) {
        /* These are taken from SP 800-90 10.1 Table 2 */
        md_size = EVP_MD_get_size(md);
        if (md_size <= 0)
            return 0;
        hmac->blocklen = (size_t)md_size;
        /* See SP800-57 Part1 Rev4 5.6.1 Table 3 */
        ctx->strength = 64 * (int)(hmac->blocklen >> 3);
        if (ctx->strength > 256)
            ctx->strength = 256;
        ctx->seedlen = hmac->blocklen;
        ctx->min_entropylen = ctx->strength / 8;
        ctx->min_noncelen = ctx->min_entropylen / 2;
    }

    return ossl_drbg_set_ctx_params(ctx, p);
}

static int drbg_hmac_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
    PROV_DRBG *drbg = (PROV_DRBG *)vctx;
    struct drbg_set_ctx_params_st p;
    int ret;

    if (drbg == NULL || !drbg_hmac_set_ctx_params_decoder(params, &p))
        return 0;

    if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
        return 0;

    ret = drbg_hmac_set_ctx_params_locked(drbg, &p);

    if (drbg->lock != NULL)
        CRYPTO_THREAD_unlock(drbg->lock);

    return ret;
}

static const OSSL_PARAM *drbg_hmac_settable_ctx_params(ossl_unused void *vctx,
                                                       ossl_unused void *p_ctx)
{
    return drbg_hmac_set_ctx_params_list;
}

const OSSL_DISPATCH ossl_drbg_ossl_hmac_functions[] = {
    { OSSL_FUNC_RAND_NEWCTX, (void(*)(void))drbg_hmac_new_wrapper },
    { OSSL_FUNC_RAND_FREECTX, (void(*)(void))drbg_hmac_free },
    { OSSL_FUNC_RAND_INSTANTIATE,
      (void(*)(void))drbg_hmac_instantiate_wrapper },
    { OSSL_FUNC_RAND_UNINSTANTIATE,
      (void(*)(void))drbg_hmac_uninstantiate_wrapper },
    { OSSL_FUNC_RAND_GENERATE, (void(*)(void))drbg_hmac_generate_wrapper },
    { OSSL_FUNC_RAND_RESEED, (void(*)(void))drbg_hmac_reseed_wrapper },
    { OSSL_FUNC_RAND_ENABLE_LOCKING, (void(*)(void))ossl_drbg_enable_locking },
    { OSSL_FUNC_RAND_LOCK, (void(*)(void))ossl_drbg_lock },
    { OSSL_FUNC_RAND_UNLOCK, (void(*)(void))ossl_drbg_unlock },
    { OSSL_FUNC_RAND_SETTABLE_CTX_PARAMS,
      (void(*)(void))drbg_hmac_settable_ctx_params },
    { OSSL_FUNC_RAND_SET_CTX_PARAMS, (void(*)(void))drbg_hmac_set_ctx_params },
    { OSSL_FUNC_RAND_GETTABLE_CTX_PARAMS,
      (void(*)(void))drbg_hmac_gettable_ctx_params },
    { OSSL_FUNC_RAND_GET_CTX_PARAMS, (void(*)(void))drbg_hmac_get_ctx_params },
    { OSSL_FUNC_RAND_VERIFY_ZEROIZATION,
      (void(*)(void))drbg_hmac_verify_zeroization },
    { OSSL_FUNC_RAND_GET_SEED, (void(*)(void))ossl_drbg_get_seed },
    { OSSL_FUNC_RAND_CLEAR_SEED, (void(*)(void))ossl_drbg_clear_seed },
    OSSL_DISPATCH_END
};

Coverage Report

Created: 2025-11-07 06:36

Line	Count	Source
1		/*
2		* Copyright 2011-2025 The OpenSSL Project Authors. All Rights Reserved.
3		*
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
8		*/
9
10		#include <stdlib.h>
11		#include <string.h>
12		#include <openssl/crypto.h>
13		#include <openssl/err.h>
14		#include <openssl/rand.h>
15		#include <openssl/proverr.h>
16		#include "internal/cryptlib.h"
17		#include "internal/thread_once.h"
18		#include "prov/providercommon.h"
19		#include "prov/implementations.h"
20		#include "prov/provider_ctx.h"
21		#include "prov/hmac_drbg.h"
22		#include "prov/drbg.h"
23		#include "crypto/evp.h"
24		#include "crypto/evp/evp_local.h"
25		#include "internal/provider.h"
26
27		#define drbg_hmac_get_ctx_params_st drbg_get_ctx_params_st
28		#define drbg_hmac_set_ctx_params_st drbg_set_ctx_params_st
29
30		#include "providers/implementations/rands/drbg_hmac.inc"
31
32		static OSSL_FUNC_rand_newctx_fn drbg_hmac_new_wrapper;
33		static OSSL_FUNC_rand_freectx_fn drbg_hmac_free;
34		static OSSL_FUNC_rand_instantiate_fn drbg_hmac_instantiate_wrapper;
35		static OSSL_FUNC_rand_uninstantiate_fn drbg_hmac_uninstantiate_wrapper;
36		static OSSL_FUNC_rand_generate_fn drbg_hmac_generate_wrapper;
37		static OSSL_FUNC_rand_reseed_fn drbg_hmac_reseed_wrapper;
38		static OSSL_FUNC_rand_settable_ctx_params_fn drbg_hmac_settable_ctx_params;
39		static OSSL_FUNC_rand_set_ctx_params_fn drbg_hmac_set_ctx_params;
40		static OSSL_FUNC_rand_gettable_ctx_params_fn drbg_hmac_gettable_ctx_params;
41		static OSSL_FUNC_rand_get_ctx_params_fn drbg_hmac_get_ctx_params;
42		static OSSL_FUNC_rand_verify_zeroization_fn drbg_hmac_verify_zeroization;
43
44		static int drbg_hmac_set_ctx_params_locked(PROV_DRBG *drbg,
45		const struct drbg_set_ctx_params_st *p);
46
47		/*
48		* Called twice by SP800-90Ar1 10.1.2.2 HMAC_DRBG_Update_Process.
49		*
50		* hmac is an object that holds the input/output Key and Value (K and V).
51		* inbyte is 0x00 on the first call and 0x01 on the second call.
52		* in1, in2, in3 are optional inputs that can be NULL.
53		* in1len, in2len, in3len are the lengths of the input buffers.
54		*
55		* The returned K,V is:
56		* hmac->K = HMAC(hmac->K, hmac->V \|\| inbyte \|\| [in1] \|\| [in2] \|\| [in3])
57		* hmac->V = HMAC(hmac->K, hmac->V)
58		*
59		* Returns zero if an error occurs otherwise it returns 1.
60		*/
61		static int do_hmac(PROV_DRBG_HMAC *hmac, unsigned char inbyte,
62		const unsigned char *in1, size_t in1len,
63		const unsigned char *in2, size_t in2len,
64		const unsigned char *in3, size_t in3len)
65	0	{
66	0	EVP_MAC_CTX *ctx = hmac->ctx;
67
68	0	if (!EVP_MAC_init(ctx, hmac->K, hmac->blocklen, NULL)
69		/* K = HMAC(K, V \|\| inbyte \|\| [in1] \|\| [in2] \|\| [in3]) */
70	0	\|\| !EVP_MAC_update(ctx, hmac->V, hmac->blocklen)
71	0	\|\| !EVP_MAC_update(ctx, &inbyte, 1)
72	0	\|\| !(in1 == NULL \|\| in1len == 0 \|\| EVP_MAC_update(ctx, in1, in1len))
73	0	\|\| !(in2 == NULL \|\| in2len == 0 \|\| EVP_MAC_update(ctx, in2, in2len))
74	0	\|\| !(in3 == NULL \|\| in3len == 0 \|\| EVP_MAC_update(ctx, in3, in3len))
75	0	\|\| !EVP_MAC_final(ctx, hmac->K, NULL, sizeof(hmac->K)))
76	0	return 0;
77
78		/* V = HMAC(K, V) */
79	0	return EVP_MAC_init(ctx, hmac->K, hmac->blocklen, NULL)
80	0	&& EVP_MAC_update(ctx, hmac->V, hmac->blocklen)
81	0	&& EVP_MAC_final(ctx, hmac->V, NULL, sizeof(hmac->V));
82	0	}
83
84		/*
85		* SP800-90Ar1 10.1.2.2 HMAC_DRBG_Update_Process
86		*
87		*
88		* Updates the drbg objects Key(K) and Value(V) using the following algorithm:
89		* K,V = do_hmac(hmac, 0, in1, in2, in3)
90		* if (any input is not NULL)
91		* K,V = do_hmac(hmac, 1, in1, in2, in3)
92		*
93		* where in1, in2, in3 are optional input buffers that can be NULL.
94		* in1len, in2len, in3len are the lengths of the input buffers.
95		*
96		* Returns zero if an error occurs otherwise it returns 1.
97		*/
98		static int drbg_hmac_update(PROV_DRBG_HMAC *hmac,
99		const unsigned char *in1, size_t in1len,
100		const unsigned char *in2, size_t in2len,
101		const unsigned char *in3, size_t in3len)
102	0	{
103		/* (Steps 1-2) K = HMAC(K, V\|\|0x00\|\|provided_data). V = HMAC(K,V) */
104	0	if (!do_hmac(hmac, 0x00, in1, in1len, in2, in2len, in3, in3len))
105	0	return 0;
106		/* (Step 3) If provided_data == NULL then return (K,V) */
107	0	if (in1len == 0 && in2len == 0 && in3len == 0)
108	0	return 1;
109		/* (Steps 4-5) K = HMAC(K, V\|\|0x01\|\|provided_data). V = HMAC(K,V) */
110	0	return do_hmac(hmac, 0x01, in1, in1len, in2, in2len, in3, in3len);
111	0	}
112
113		/*
114		* SP800-90Ar1 10.1.2.3 HMAC_DRBG_Instantiate_Process:
115		*
116		* This sets the drbg Key (K) to all zeros, and Value (V) to all 1's.
117		* and then calls (K,V) = drbg_hmac_update() with input parameters:
118		* ent = entropy data (Can be NULL) of length ent_len.
119		* nonce = nonce data (Can be NULL) of length nonce_len.
120		* pstr = personalization data (Can be NULL) of length pstr_len.
121		*
122		* Returns zero if an error occurs otherwise it returns 1.
123		*/
124		int ossl_drbg_hmac_init(PROV_DRBG_HMAC *hmac,
125		const unsigned char *ent, size_t ent_len,
126		const unsigned char *nonce, size_t nonce_len,
127		const unsigned char *pstr, size_t pstr_len)
128	0	{
129	0	if (hmac->ctx == NULL) {
130	0	ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MAC);
131	0	return 0;
132	0	}
133
134		/* (Step 2) Key = 0x00 00...00 */
135	0	memset(hmac->K, 0x00, hmac->blocklen);
136		/* (Step 3) V = 0x01 01...01 */
137	0	memset(hmac->V, 0x01, hmac->blocklen);
138		/* (Step 4) (K,V) = HMAC_DRBG_Update(entropy\|\|nonce\|\|pers string, K, V) */
139	0	return drbg_hmac_update(hmac, ent, ent_len, nonce, nonce_len, pstr,
140	0	pstr_len);
141	0	}
142		static int drbg_hmac_instantiate(PROV_DRBG *drbg,
143		const unsigned char *ent, size_t ent_len,
144		const unsigned char *nonce, size_t nonce_len,
145		const unsigned char *pstr, size_t pstr_len)
146	0	{
147	0	return ossl_drbg_hmac_init((PROV_DRBG_HMAC *)drbg->data, ent, ent_len,
148	0	nonce, nonce_len, pstr, pstr_len);
149	0	}
150
151		static int drbg_hmac_instantiate_wrapper(void *vdrbg, unsigned int strength,
152		int prediction_resistance,
153		const unsigned char *pstr,
154		size_t pstr_len,
155		const OSSL_PARAM params[])
156	0	{
157	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
158	0	struct drbg_set_ctx_params_st p;
159	0	int ret = 0;
160
161	0	if (drbg == NULL \|\| !drbg_hmac_set_ctx_params_decoder(params, &p))
162	0	return 0;
163
164	0	if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
165	0	return 0;
166
167	0	if (!ossl_prov_is_running()
168	0	\|\| !drbg_hmac_set_ctx_params_locked(drbg, &p))
169	0	goto err;
170	0	ret = ossl_prov_drbg_instantiate(drbg, strength, prediction_resistance,
171	0	pstr, pstr_len);
172	0	err:
173	0	if (drbg->lock != NULL)
174	0	CRYPTO_THREAD_unlock(drbg->lock);
175	0	return ret;
176	0	}
177
178		/*
179		* SP800-90Ar1 10.1.2.4 HMAC_DRBG_Reseed_Process:
180		*
181		* Reseeds the drbg's Key (K) and Value (V) by calling
182		* (K,V) = drbg_hmac_update() with the following input parameters:
183		* ent = entropy input data (Can be NULL) of length ent_len.
184		* adin = additional input data (Can be NULL) of length adin_len.
185		*
186		* Returns zero if an error occurs otherwise it returns 1.
187		*/
188		static int drbg_hmac_reseed(PROV_DRBG *drbg,
189		const unsigned char *ent, size_t ent_len,
190		const unsigned char *adin, size_t adin_len)
191	0	{
192	0	PROV_DRBG_HMAC hmac = (PROV_DRBG_HMAC )drbg->data;
193
194		/* (Step 2) (K,V) = HMAC_DRBG_Update(entropy\|\|additional_input, K, V) */
195	0	return drbg_hmac_update(hmac, ent, ent_len, adin, adin_len, NULL, 0);
196	0	}
197
198		static int drbg_hmac_reseed_wrapper(void *vdrbg, int prediction_resistance,
199		const unsigned char *ent, size_t ent_len,
200		const unsigned char *adin, size_t adin_len)
201	0	{
202	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
203
204	0	return ossl_prov_drbg_reseed(drbg, prediction_resistance, ent, ent_len,
205	0	adin, adin_len);
206	0	}
207
208		/*
209		* SP800-90Ar1 10.1.2.5 HMAC_DRBG_Generate_Process:
210		*
211		* Generates pseudo random bytes and updates the internal K,V for the drbg.
212		* out is a buffer to fill with outlen bytes of pseudo random data.
213		* adin is an additional_input string of size adin_len that may be NULL.
214		*
215		* Returns zero if an error occurs otherwise it returns 1.
216		*/
217		int ossl_drbg_hmac_generate(PROV_DRBG_HMAC *hmac,
218		unsigned char *out, size_t outlen,
219		const unsigned char *adin, size_t adin_len)
220	0	{
221	0	EVP_MAC_CTX *ctx = hmac->ctx;
222	0	const unsigned char *temp = hmac->V;
223
224		/* (Step 2) if adin != NULL then (K,V) = HMAC_DRBG_Update(adin, K, V) */
225	0	if (adin != NULL
226	0	&& adin_len > 0
227	0	&& !drbg_hmac_update(hmac, adin, adin_len, NULL, 0, NULL, 0))
228	0	return 0;
229
230		/*
231		* (Steps 3-5) temp = NULL
232		* while (len(temp) < outlen) {
233		* V = HMAC(K, V)
234		* temp = temp \|\| V
235		* }
236		*/
237	0	for (;;) {
238	0	if (!EVP_MAC_init(ctx, hmac->K, hmac->blocklen, NULL)
239	0	\|\| !EVP_MAC_update(ctx, temp, hmac->blocklen))
240	0	return 0;
241
242	0	if (outlen > hmac->blocklen) {
243	0	if (!EVP_MAC_final(ctx, out, NULL, outlen))
244	0	return 0;
245	0	temp = out;
246	0	} else {
247	0	if (!EVP_MAC_final(ctx, hmac->V, NULL, sizeof(hmac->V)))
248	0	return 0;
249	0	memcpy(out, hmac->V, outlen);
250	0	break;
251	0	}
252	0	out += hmac->blocklen;
253	0	outlen -= hmac->blocklen;
254	0	}
255		/* (Step 6) (K,V) = HMAC_DRBG_Update(adin, K, V) */
256	0	if (!drbg_hmac_update(hmac, adin, adin_len, NULL, 0, NULL, 0))
257	0	return 0;
258
259	0	return 1;
260	0	}
261
262		static int drbg_hmac_generate(PROV_DRBG *drbg,
263		unsigned char *out, size_t outlen,
264		const unsigned char *adin, size_t adin_len)
265	0	{
266	0	return ossl_drbg_hmac_generate((PROV_DRBG_HMAC *)drbg->data, out, outlen,
267	0	adin, adin_len);
268	0	}
269
270		static int drbg_hmac_generate_wrapper(void *vdrbg,
271		unsigned char *out, size_t outlen, unsigned int strength,
272		int prediction_resistance, const unsigned char *adin, size_t adin_len)
273	0	{
274	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
275
276	0	return ossl_prov_drbg_generate(drbg, out, outlen, strength,
277	0	prediction_resistance, adin, adin_len);
278	0	}
279
280		static int drbg_hmac_uninstantiate(PROV_DRBG *drbg)
281	0	{
282	0	PROV_DRBG_HMAC hmac = (PROV_DRBG_HMAC )drbg->data;
283
284	0	OPENSSL_cleanse(hmac->K, sizeof(hmac->K));
285	0	OPENSSL_cleanse(hmac->V, sizeof(hmac->V));
286	0	return ossl_prov_drbg_uninstantiate(drbg);
287	0	}
288
289		static int drbg_hmac_uninstantiate_wrapper(void *vdrbg)
290	0	{
291	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
292	0	int ret;
293
294	0	if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
295	0	return 0;
296
297	0	ret = drbg_hmac_uninstantiate(drbg);
298
299	0	if (drbg->lock != NULL)
300	0	CRYPTO_THREAD_unlock(drbg->lock);
301
302	0	return ret;
303	0	}
304
305		static int drbg_hmac_verify_zeroization(void *vdrbg)
306	0	{
307	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
308	0	PROV_DRBG_HMAC hmac = (PROV_DRBG_HMAC )drbg->data;
309	0	int ret = 0;
310
311	0	if (drbg->lock != NULL && !CRYPTO_THREAD_read_lock(drbg->lock))
312	0	return 0;
313
314	0	PROV_DRBG_VERIFY_ZEROIZATION(hmac->K);
315	0	PROV_DRBG_VERIFY_ZEROIZATION(hmac->V);
316
317	0	ret = 1;
318	0	err:
319	0	if (drbg->lock != NULL)
320	0	CRYPTO_THREAD_unlock(drbg->lock);
321	0	return ret;
322	0	}
323
324		static int drbg_hmac_new(PROV_DRBG *drbg)
325	0	{
326	0	PROV_DRBG_HMAC *hmac;
327
328	0	hmac = OPENSSL_secure_zalloc(sizeof(*hmac));
329	0	if (hmac == NULL)
330	0	return 0;
331
332	0	OSSL_FIPS_IND_INIT(drbg)
333
334	0	drbg->data = hmac;
335		/* See SP800-57 Part1 Rev4 5.6.1 Table 3 */
336	0	drbg->max_entropylen = DRBG_MAX_LENGTH;
337	0	drbg->max_noncelen = DRBG_MAX_LENGTH;
338	0	drbg->max_perslen = DRBG_MAX_LENGTH;
339	0	drbg->max_adinlen = DRBG_MAX_LENGTH;
340
341		/* Maximum number of bits per request = 2^19 = 2^16 bytes */
342	0	drbg->max_request = 1 << 16;
343	0	return 1;
344	0	}
345
346		static void drbg_hmac_new_wrapper(void provctx, void *parent,
347		const OSSL_DISPATCH *parent_dispatch)
348	0	{
349	0	return ossl_rand_drbg_new(provctx, parent, parent_dispatch,
350	0	&drbg_hmac_new, &drbg_hmac_free,
351	0	&drbg_hmac_instantiate, &drbg_hmac_uninstantiate,
352	0	&drbg_hmac_reseed, &drbg_hmac_generate);
353	0	}
354
355		static void drbg_hmac_free(void *vdrbg)
356	0	{
357	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
358	0	PROV_DRBG_HMAC *hmac;
359
360	0	if (drbg != NULL && (hmac = (PROV_DRBG_HMAC *)drbg->data) != NULL) {
361	0	EVP_MAC_CTX_free(hmac->ctx);
362	0	ossl_prov_digest_reset(&hmac->digest);
363	0	OPENSSL_secure_clear_free(hmac, sizeof(*hmac));
364	0	}
365	0	ossl_rand_drbg_free(drbg);
366	0	}
367
368		static int drbg_hmac_get_ctx_params(void *vdrbg, OSSL_PARAM params[])
369	0	{
370	0	PROV_DRBG drbg = (PROV_DRBG )vdrbg;
371	0	PROV_DRBG_HMAC *hmac;
372	0	const EVP_MD *md;
373	0	struct drbg_get_ctx_params_st p;
374	0	int ret = 0, complete = 0;
375
376	0	if (drbg == NULL \|\| !drbg_hmac_get_ctx_params_decoder(params, &p))
377	0	return 0;
378
379	0	if (!ossl_drbg_get_ctx_params_no_lock(drbg, &p, params, &complete))
380	0	return 0;
381
382	0	if (complete)
383	0	return 1;
384
385	0	hmac = (PROV_DRBG_HMAC *)drbg->data;
386
387	0	if (drbg->lock != NULL && !CRYPTO_THREAD_read_lock(drbg->lock))
388	0	return 0;
389
390	0	if (p.digest != NULL) {
391	0	md = ossl_prov_digest_md(&hmac->digest);
392	0	if (md == NULL
393	0	\|\| !OSSL_PARAM_set_utf8_string(p.digest, EVP_MD_get0_name(md)))
394	0	goto err;
395	0	}
396
397	0	ret = ossl_drbg_get_ctx_params(drbg, &p);
398	0	err:
399	0	if (drbg->lock != NULL)
400	0	CRYPTO_THREAD_unlock(drbg->lock);
401
402	0	return ret;
403	0	}
404
405		static const OSSL_PARAM drbg_hmac_gettable_ctx_params(ossl_unused void vctx,
406		ossl_unused void *p_ctx)
407	0	{
408	0	return drbg_hmac_get_ctx_params_list;
409	0	}
410
411		static int drbg_fetch_algs_from_prov(const struct drbg_set_ctx_params_st *p,
412		OSSL_LIB_CTX *libctx,
413		EVP_MAC_CTX **macctx,
414		EVP_MD **digest)
415	0	{
416	0	OSSL_PROVIDER *prov = NULL;
417	0	EVP_MD *md = NULL;
418	0	int ret = 0;
419
420	0	if (macctx == NULL \|\| digest == NULL)
421	0	return 0;
422
423	0	if (p->prov == NULL \|\| p->prov->data_type != OSSL_PARAM_UTF8_STRING)
424	0	return 0;
425	0	if ((prov = ossl_provider_find(libctx, (const char *)p->prov->data, 1)) == NULL)
426	0	return 0;
427
428	0	if (p->digest != NULL) {
429	0	if (p->digest->data_type != OSSL_PARAM_UTF8_STRING)
430	0	goto done;
431
432	0	md = evp_digest_fetch_from_prov(prov, (const char *)p->digest->data, NULL);
433	0	if (md) {
434	0	EVP_MD_free(*digest);
435	0	*digest = md;
436	0	} else {
437	0	goto done;
438	0	}
439	0	}
440
441	0	ret = 1;
442
443	0	done:
444	0	ossl_provider_free(prov);
445	0	return ret;
446	0	}
447
448		static int drbg_hmac_set_ctx_params_locked
449		(PROV_DRBG ctx, const struct drbg_set_ctx_params_st p)
450	0	{
451	0	PROV_DRBG_HMAC hmac = (PROV_DRBG_HMAC )ctx->data;
452	0	OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
453	0	EVP_MD *prov_md = NULL;
454	0	const EVP_MD *md;
455	0	int md_size;
456
457	0	if (!OSSL_FIPS_IND_SET_CTX_FROM_PARAM(ctx, OSSL_FIPS_IND_SETTABLE0, p->ind_d))
458	0	return 0;
459
460		/* try to fetch mac and digest from provider */
461	0	(void)ERR_set_mark();
462	0	if (!drbg_fetch_algs_from_prov(p, libctx, &hmac->ctx, &prov_md)) {
463	0	(void)ERR_pop_to_mark();
464	0	if (p->digest != NULL) {
465		/* fall back to full implementation search */
466	0	if (!ossl_prov_digest_load(&hmac->digest, p->digest, p->propq,
467	0	p->engine, libctx))
468	0	return 0;
469
470	0	if (!ossl_prov_macctx_load(&hmac->ctx, NULL, NULL, p->digest,
471	0	p->propq, p->engine,
472	0	"HMAC", NULL, NULL, libctx))
473	0	return 0;
474	0	}
475	0	} else {
476	0	(void)ERR_clear_last_mark();
477	0	if (prov_md)
478	0	ossl_prov_digest_set_md(&hmac->digest, prov_md);
479	0	}
480
481	0	md = ossl_prov_digest_md(&hmac->digest);
482	0	if (md != NULL && !ossl_drbg_verify_digest(ctx, libctx, md))
483	0	return 0; /* Error already raised for us */
484
485	0	if (md != NULL && hmac->ctx != NULL) {
486		/* These are taken from SP 800-90 10.1 Table 2 */
487	0	md_size = EVP_MD_get_size(md);
488	0	if (md_size <= 0)
489	0	return 0;
490	0	hmac->blocklen = (size_t)md_size;
491		/* See SP800-57 Part1 Rev4 5.6.1 Table 3 */
492	0	ctx->strength = 64 * (int)(hmac->blocklen >> 3);
493	0	if (ctx->strength > 256)
494	0	ctx->strength = 256;
495	0	ctx->seedlen = hmac->blocklen;
496	0	ctx->min_entropylen = ctx->strength / 8;
497	0	ctx->min_noncelen = ctx->min_entropylen / 2;
498	0	}
499
500	0	return ossl_drbg_set_ctx_params(ctx, p);
501	0	}
502
503		static int drbg_hmac_set_ctx_params(void *vctx, const OSSL_PARAM params[])
504	0	{
505	0	PROV_DRBG drbg = (PROV_DRBG )vctx;
506	0	struct drbg_set_ctx_params_st p;
507	0	int ret;
508
509	0	if (drbg == NULL \|\| !drbg_hmac_set_ctx_params_decoder(params, &p))
510	0	return 0;
511
512	0	if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
513	0	return 0;
514
515	0	ret = drbg_hmac_set_ctx_params_locked(drbg, &p);
516
517	0	if (drbg->lock != NULL)
518	0	CRYPTO_THREAD_unlock(drbg->lock);
519
520	0	return ret;
521	0	}
522
523		static const OSSL_PARAM drbg_hmac_settable_ctx_params(ossl_unused void vctx,
524		ossl_unused void *p_ctx)
525	0	{
526	0	return drbg_hmac_set_ctx_params_list;
527	0	}
528
529		const OSSL_DISPATCH ossl_drbg_ossl_hmac_functions[] = {
530		{ OSSL_FUNC_RAND_NEWCTX, (void(*)(void))drbg_hmac_new_wrapper },
531		{ OSSL_FUNC_RAND_FREECTX, (void(*)(void))drbg_hmac_free },
532		{ OSSL_FUNC_RAND_INSTANTIATE,
533		(void(*)(void))drbg_hmac_instantiate_wrapper },
534		{ OSSL_FUNC_RAND_UNINSTANTIATE,
535		(void(*)(void))drbg_hmac_uninstantiate_wrapper },
536		{ OSSL_FUNC_RAND_GENERATE, (void(*)(void))drbg_hmac_generate_wrapper },
537		{ OSSL_FUNC_RAND_RESEED, (void(*)(void))drbg_hmac_reseed_wrapper },
538		{ OSSL_FUNC_RAND_ENABLE_LOCKING, (void(*)(void))ossl_drbg_enable_locking },
539		{ OSSL_FUNC_RAND_LOCK, (void(*)(void))ossl_drbg_lock },
540		{ OSSL_FUNC_RAND_UNLOCK, (void(*)(void))ossl_drbg_unlock },
541		{ OSSL_FUNC_RAND_SETTABLE_CTX_PARAMS,
542		(void(*)(void))drbg_hmac_settable_ctx_params },
543		{ OSSL_FUNC_RAND_SET_CTX_PARAMS, (void(*)(void))drbg_hmac_set_ctx_params },
544		{ OSSL_FUNC_RAND_GETTABLE_CTX_PARAMS,
545		(void(*)(void))drbg_hmac_gettable_ctx_params },
546		{ OSSL_FUNC_RAND_GET_CTX_PARAMS, (void(*)(void))drbg_hmac_get_ctx_params },
547		{ OSSL_FUNC_RAND_VERIFY_ZEROIZATION,
548		(void(*)(void))drbg_hmac_verify_zeroization },
549		{ OSSL_FUNC_RAND_GET_SEED, (void(*)(void))ossl_drbg_get_seed },
550		{ OSSL_FUNC_RAND_CLEAR_SEED, (void(*)(void))ossl_drbg_clear_seed },
551		OSSL_DISPATCH_END
552		};