/*
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */
#ifndef MBEDTLS_ENTROPY_H
#define MBEDTLS_ENTROPY_H
#include "mbedtls/private_access.h"

#include "mbedtls/build_info.h"

#include <stddef.h>

#include "md.h"

#if (defined(MBEDTLS_MD_CAN_SHA512) || defined(PSA_WANT_ALG_SHA_512)) && \
    !defined(MBEDTLS_ENTROPY_FORCE_SHA256)
#define MBEDTLS_ENTROPY_SHA512_ACCUMULATOR
#define MBEDTLS_ENTROPY_MD  MBEDTLS_MD_SHA512
#define MBEDTLS_ENTROPY_BLOCK_SIZE      64
#else
#if (defined(MBEDTLS_MD_CAN_SHA256) || defined(PSA_WANT_ALG_SHA_256))
#define MBEDTLS_ENTROPY_SHA256_ACCUMULATOR
#define MBEDTLS_ENTROPY_MD  MBEDTLS_MD_SHA256
#define MBEDTLS_ENTROPY_BLOCK_SIZE      32
#endif
#endif

#if defined(MBEDTLS_THREADING_C)
#include "mbedtls/threading.h"
#endif

#define MBEDTLS_ERR_ENTROPY_SOURCE_FAILED                 -0x003C

#define MBEDTLS_ERR_ENTROPY_MAX_SOURCES                   -0x003E

#define MBEDTLS_ERR_ENTROPY_NO_SOURCES_DEFINED            -0x0040

#define MBEDTLS_ERR_ENTROPY_NO_STRONG_SOURCE              -0x003D

#define MBEDTLS_ERR_ENTROPY_FILE_IO_ERROR                 -0x003F

#if !defined(MBEDTLS_ENTROPY_MAX_SOURCES)
#define MBEDTLS_ENTROPY_MAX_SOURCES     20
#endif

#if !defined(MBEDTLS_ENTROPY_MAX_GATHER)
#define MBEDTLS_ENTROPY_MAX_GATHER      128
#endif

#define MBEDTLS_ENTROPY_MAX_SEED_SIZE   1024
#define MBEDTLS_ENTROPY_SOURCE_MANUAL   MBEDTLS_ENTROPY_MAX_SOURCES

#define MBEDTLS_ENTROPY_SOURCE_STRONG   1
#define MBEDTLS_ENTROPY_SOURCE_WEAK     0

#ifdef __cplusplus
extern "C" {
#endif

typedef int (*mbedtls_entropy_f_source_ptr)(void *data, unsigned char *output, size_t len,
                                            size_t *olen);

typedef struct mbedtls_entropy_source_state {
    mbedtls_entropy_f_source_ptr    MBEDTLS_PRIVATE(f_source);
    void *MBEDTLS_PRIVATE(p_source);
    size_t          MBEDTLS_PRIVATE(size);
    size_t          MBEDTLS_PRIVATE(threshold);
    int             MBEDTLS_PRIVATE(strong);
}
mbedtls_entropy_source_state;

typedef struct mbedtls_entropy_context {
    mbedtls_md_context_t  MBEDTLS_PRIVATE(accumulator);
    int MBEDTLS_PRIVATE(accumulator_started);
    int             MBEDTLS_PRIVATE(source_count);
    mbedtls_entropy_source_state    MBEDTLS_PRIVATE(source)[MBEDTLS_ENTROPY_MAX_SOURCES];
#if defined(MBEDTLS_THREADING_C)
    mbedtls_threading_mutex_t MBEDTLS_PRIVATE(mutex);
#endif
#if defined(MBEDTLS_ENTROPY_NV_SEED)
    int MBEDTLS_PRIVATE(initial_entropy_run);
#endif
}
mbedtls_entropy_context;

#if !defined(MBEDTLS_NO_PLATFORM_ENTROPY)

int mbedtls_platform_entropy_poll(void *data,
                                  unsigned char *output, size_t len, size_t *olen);
#endif

void mbedtls_entropy_init(mbedtls_entropy_context *ctx);

void mbedtls_entropy_free(mbedtls_entropy_context *ctx);

int mbedtls_entropy_add_source(mbedtls_entropy_context *ctx,
                               mbedtls_entropy_f_source_ptr f_source, void *p_source,
                               size_t threshold, int strong);

int mbedtls_entropy_gather(mbedtls_entropy_context *ctx);

int mbedtls_entropy_func(void *data, unsigned char *output, size_t len);

int mbedtls_entropy_update_manual(mbedtls_entropy_context *ctx,
                                  const unsigned char *data, size_t len);

#if defined(MBEDTLS_ENTROPY_NV_SEED)

int mbedtls_entropy_update_nv_seed(mbedtls_entropy_context *ctx);
#endif

#if defined(MBEDTLS_FS_IO)

int mbedtls_entropy_write_seed_file(mbedtls_entropy_context *ctx, const char *path);

int mbedtls_entropy_update_seed_file(mbedtls_entropy_context *ctx, const char *path);
#endif

#if defined(MBEDTLS_SELF_TEST)

int mbedtls_entropy_self_test(int verbose);

#if defined(MBEDTLS_ENTROPY_HARDWARE_ALT)

int mbedtls_entropy_source_self_test(int verbose);
#endif
#endif

#ifdef __cplusplus
}
#endif

#endif
