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/*
* Copyright 2011-2021 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 "prov/provider_util.h"
#include "internal/thread_once.h"
#include "prov/providercommon.h"
#include "prov/implementations.h"
#include "prov/provider_ctx.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;
typedef struct rand_drbg_hmac_st {
EVP_MAC_CTX *ctx; /* H(x) = HMAC_hash OR H(x) = KMAC */
PROV_DIGEST digest; /* H(x) = hash(x) */
size_t blocklen;
unsigned char K[EVP_MAX_MD_SIZE];
unsigned char V[EVP_MAX_MD_SIZE];
} PROV_DRBG_HMAC;
/*
* 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;
OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
*params = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY, hmac->K,
hmac->blocklen);
if (!EVP_MAC_CTX_set_params(ctx, params)
|| !EVP_MAC_init(ctx)
/* 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) */
*params = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY, hmac->K,
hmac->blocklen);
return EVP_MAC_CTX_set_params(ctx, params)
&& EVP_MAC_init(ctx)
&& 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 *drbg,
const unsigned char *in1, size_t in1len,
const unsigned char *in2, size_t in2len,
const unsigned char *in3, size_t in3len)
{
PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)drbg->data;
/* (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.
*/
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)
{
PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)drbg->data;
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(drbg, 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)
{
PROV_DRBG *drbg = (PROV_DRBG *)vdrbg;
return ossl_prov_drbg_instantiate(drbg, strength, prediction_resistance,
pstr, pstr_len);
}
/*
* 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)
{
/* (Step 2) (K,V) = HMAC_DRBG_Update(entropy||additional_input, K, V) */
return drbg_hmac_update(drbg, 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.
*/
static int drbg_hmac_generate(PROV_DRBG *drbg,
unsigned char *out, size_t outlen,
const unsigned char *adin, size_t adin_len)
{
PROV_DRBG_HMAC *hmac = (PROV_DRBG_HMAC *)drbg->data;
EVP_MAC_CTX *ctx = hmac->ctx;
const unsigned char *temp = hmac->V;
OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
/* (Step 2) if adin != NULL then (K,V) = HMAC_DRBG_Update(adin, K, V) */
if (adin != NULL
&& adin_len > 0
&& !drbg_hmac_update(drbg, 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 (;;) {
*params = OSSL_PARAM_construct_octet_string(OSSL_MAC_PARAM_KEY,
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