/*
* Copyright 2011-2024 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/thread_once.h"
#include "prov/providercommon.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.h"
#include "prov/hmac_drbg.h"
#include "drbg_local.h"
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(void *vctx, const OSSL_PARAM params[]);
/*
* 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;
int ret = 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, params))
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 = (PROV_DRBG_HMAC *)drbg->data;
const char *name;
const EVP_MD *md;
OSSL_PARAM *p;
int ret = 0, complete = 0;
if (!ossl_drbg_get_ctx_params_no_lock(drbg, params, &complete))
return 0;
if (complete)
return 1;
if (drbg->lock != NULL && !CRYPTO_THREAD_read_lock(drbg->lock))
return 0;
p = OSSL_PARAM_locate(params, OSSL_DRBG_PARAM_MAC);
if (p != NULL) {
if (hmac->ctx == NULL)
goto err;
name = EVP_MAC_get0_name(EVP_MAC_CTX_get0_mac(hmac->ctx));
if (!OSSL_PARAM_set_utf8_string(p, name))
goto err;
}
p = OSSL_PARAM_locate(params, OSSL_DRBG_PARAM_DIGEST);
if (p != NULL) {
md = ossl_prov_digest_md(&hmac->digest);
if (md == NULL || !OSSL_PARAM_set_utf8_string(p, EVP_MD_get0_name(md)))
goto err;
}
ret = ossl_drbg_get_ctx_params(drbg, params);
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)
{
static const OSSL_PARAM known_gettable_ctx_params[] = {
OSSL_PARAM_utf8_string(OSSL_DRBG_PARAM_MAC, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_DRBG_PARAM_DIGEST, NULL, 0),
OSSL_PARAM_DRBG_GETTABLE_CTX_COMMON,
OSSL_FIPS_IND_GETTABLE_CTX_PARAM()
OSSL_PARAM_END
};
return known_gettable_ctx_params;
}
static int drbg_hmac_set_ctx_params_locked(void *vctx, const OSSL_PARAM params[])
{
PROV_DRBG *ctx = (PROV_DRBG *)vctx;
PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)ctx->data;
OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(ctx->provctx);
const EVP_MD *md;
int md_size;
if (!OSSL_FIPS_IND_SET_CTX_PARAM(ctx, OSSL_FIPS_IND_SETTABLE0, params,
OSSL_DRBG_PARAM_FIPS_DIGEST_CHECK))
return 0;
if (!ossl_prov_digest_load_from_params(&hmac->digest, params, libctx))
return 0;
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 (!ossl_prov_macctx_load_from_params(&hmac->ctx, params,
NULL, NULL, NULL, libctx))
return 0;
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, params);
}
static int drbg_hmac_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
PROV_DRBG *drbg = (PROV_DRBG *)vctx;
int ret;
if (drbg->lock != NULL && !CRYPTO_THREAD_write_lock(drbg->lock))
return 0;
ret = drbg_hmac_set_ctx_params_locked(vctx, params);
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)
{
static const OSSL_PARAM known_settable_ctx_params[] = {
OSSL_PARAM_utf8_string(OSSL_DRBG_PARAM_PROPERTIES, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_DRBG_PARAM_DIGEST, NULL, 0),
OSSL_PARAM_utf8_string(OSSL_DRBG_PARAM_MAC, NULL, 0),
OSSL_PARAM_DRBG_SETTABLE_CTX_COMMON,
OSSL_FIPS_IND_SETTABLE_CTX_PARAM(OSSL_DRBG_PARAM_FIPS_DIGEST_CHECK)
OSSL_PARAM_END
};
return known_settable_ctx_params;
}
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
};
