// SPDX-License-Identifier: Apache-2.0 and Unknown
//
/*
NIST-developed software is provided by NIST as a public service. You may use,
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such change. Please explicitly acknowledge the National Institute of Standards
and Technology as the source of the software.

NIST-developed software is expressly provided "AS IS." NIST MAKES NO WARRANTY OF
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WITHOUT LIMITATION, THE IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
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You are solely responsible for determining the appropriateness of using and
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*/

#include <string.h>

#include <rng.h>
#include "ctr_drbg.h"

#ifdef ENABLE_CT_TESTING
#include <valgrind/memcheck.h>
#endif

#define RNG_SUCCESS 0
#define RNG_BAD_MAXLEN -1
#define RNG_BAD_OUTBUF -2
#define RNG_BAD_REQ_LEN -3

CTR_DRBG_STATE drbg;

#ifndef CTRDRBG_TEST_BENCH
static
#endif
void
randombytes_init_aes_ni(unsigned char *entropy_input,
                        unsigned char *personalization_string,
                        int security_strength) {
  (void)security_strength; // fixed to 256
  CTR_DRBG_init(&drbg, entropy_input, personalization_string,
                (personalization_string == NULL) ? 0 : CTR_DRBG_ENTROPY_LEN);
}

#ifndef CTRDRBG_TEST_BENCH
static
#endif
int
randombytes_aes_ni(unsigned char *x, size_t xlen) {
  CTR_DRBG_generate(&drbg, x, xlen, NULL, 0);
  return RNG_SUCCESS;
}

#ifdef RANDOMBYTES_AES_NI
SQISIGN_API
int randombytes(unsigned char *random_array, unsigned long long nbytes) {
  int ret = randombytes_aes_ni(random_array, nbytes);
#ifdef ENABLE_CT_TESTING
  VALGRIND_MAKE_MEM_UNDEFINED(random_array, ret);
#endif
  return ret;
}

SQISIGN_API
void randombytes_init(unsigned char *entropy_input,
                      unsigned char *personalization_string,
                      int security_strength) {
  randombytes_init_aes_ni(entropy_input, personalization_string,
                          security_strength);
}
#endif