godot/thirdparty/mbedtls/library/hmac_drbg.c

/*
 *  HMAC_DRBG implementation (NIST SP 800-90)
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */

/*
 *  The NIST SP 800-90A DRBGs are described in the following publication.
 *  http://csrc.nist.gov/publications/nistpubs/800-90A/SP800-90A.pdf
 *  References below are based on rev. 1 (January 2012).
 */

#include "common.h"

#if defined(MBEDTLS_HMAC_DRBG_C)

#include "mbedtls/hmac_drbg.h"
#include "mbedtls/platform_util.h"
#include "mbedtls/error.h"

#include <string.h>

#if defined(MBEDTLS_FS_IO)
#include <stdio.h>
#endif

#include "mbedtls/platform.h"

/*
 * HMAC_DRBG context initialization
 */
void mbedtls_hmac_drbg_init(mbedtls_hmac_drbg_context *ctx)
{ … }

/*
 * HMAC_DRBG update, using optional additional data (10.1.2.2)
 */
int mbedtls_hmac_drbg_update(mbedtls_hmac_drbg_context *ctx,
                             const unsigned char *additional,
                             size_t add_len)
{ … }

/*
 * Simplified HMAC_DRBG initialisation (for use with deterministic ECDSA)
 */
int mbedtls_hmac_drbg_seed_buf(mbedtls_hmac_drbg_context *ctx,
                               const mbedtls_md_info_t *md_info,
                               const unsigned char *data, size_t data_len)
{ … }

/*
 * Internal function used both for seeding and reseeding the DRBG.
 * Comments starting with arabic numbers refer to section 10.1.2.4
 * of SP800-90A, while roman numbers refer to section 9.2.
 */
static int hmac_drbg_reseed_core(mbedtls_hmac_drbg_context *ctx,
                                 const unsigned char *additional, size_t len,
                                 int use_nonce)
{ … }

/*
 * HMAC_DRBG reseeding: 10.1.2.4 + 9.2
 */
int mbedtls_hmac_drbg_reseed(mbedtls_hmac_drbg_context *ctx,
                             const unsigned char *additional, size_t len)
{ … }

/*
 * HMAC_DRBG initialisation (10.1.2.3 + 9.1)
 *
 * The nonce is not passed as a separate parameter but extracted
 * from the entropy source as suggested in 8.6.7.
 */
int mbedtls_hmac_drbg_seed(mbedtls_hmac_drbg_context *ctx,
                           const mbedtls_md_info_t *md_info,
                           int (*f_entropy)(void *, unsigned char *, size_t),
                           void *p_entropy,
                           const unsigned char *custom,
                           size_t len)
{ … }

/*
 * Set prediction resistance
 */
void mbedtls_hmac_drbg_set_prediction_resistance(mbedtls_hmac_drbg_context *ctx,
                                                 int resistance)
{ … }

/*
 * Set entropy length grabbed for seeding
 */
void mbedtls_hmac_drbg_set_entropy_len(mbedtls_hmac_drbg_context *ctx, size_t len)
{ … }

/*
 * Set reseed interval
 */
void mbedtls_hmac_drbg_set_reseed_interval(mbedtls_hmac_drbg_context *ctx, int interval)
{ … }

/*
 * HMAC_DRBG random function with optional additional data:
 * 10.1.2.5 (arabic) + 9.3 (Roman)
 */
int mbedtls_hmac_drbg_random_with_add(void *p_rng,
                                      unsigned char *output, size_t out_len,
                                      const unsigned char *additional, size_t add_len)
{ … }

/*
 * HMAC_DRBG random function
 */
int mbedtls_hmac_drbg_random(void *p_rng, unsigned char *output, size_t out_len)
{ … }

/*
 *  This function resets HMAC_DRBG context to the state immediately
 *  after initial call of mbedtls_hmac_drbg_init().
 */
void mbedtls_hmac_drbg_free(mbedtls_hmac_drbg_context *ctx)
{ … }

#if defined(MBEDTLS_FS_IO)
int mbedtls_hmac_drbg_write_seed_file(mbedtls_hmac_drbg_context *ctx, const char *path)
{ … }

int mbedtls_hmac_drbg_update_seed_file(mbedtls_hmac_drbg_context *ctx, const char *path)
{ … }
#endif /* MBEDTLS_FS_IO */


#if defined(MBEDTLS_SELF_TEST)

#if !defined(MBEDTLS_MD_CAN_SHA1)
/* Dummy checkup routine */
int mbedtls_hmac_drbg_self_test(int verbose)
{
    (void) verbose;
    return 0;
}
#else

#define OUTPUT_LEN …

/* From a NIST PR=true test vector */
static const unsigned char entropy_pr[] = …;
static const unsigned char result_pr[OUTPUT_LEN] = …;

/* From a NIST PR=false test vector */
static const unsigned char entropy_nopr[] = …;
static const unsigned char result_nopr[OUTPUT_LEN] = …;

/* "Entropy" from buffer */
static size_t test_offset;
static int hmac_drbg_self_test_entropy(void *data,
                                       unsigned char *buf, size_t len)
{ … }

#define CHK(c) …

/*
 * Checkup routine for HMAC_DRBG with SHA-1
 */
int mbedtls_hmac_drbg_self_test(int verbose)
{ … }
#endif /* MBEDTLS_MD_CAN_SHA1 */
#endif /* MBEDTLS_SELF_TEST */

#endif /* MBEDTLS_HMAC_DRBG_C */