/* Copyright (c) 2018, The Tor Project, Inc. */
/* See LICENSE for licensing information */

#ifndef CRYPTO_OPE_H
#define CRYPTO_OPE_H

#include "orconfig.h"
#include "crypto.h"
#include "crypto_util.h"

#include "crypto_ope.h"

/** Length of OPE key, in bytes. */
#define OPE_KEY_LEN 32

/** Largest value that can be passed to crypto_ope_encrypt() */
#define OPE_INPUT_MAX 131072

typedef struct crypto_ope_c crypto_ope_t;

crypto_ope_t *crypto_ope_new(const uint8_t *key);
void crypto_ope_free_(crypto_ope_t *ope);
#define crypto_ope_free(ope) \
  FREE_AND_NULL(crypto_ope_t, crypto_ope_free_, (ope))

uint64_t crypto_ope_encrypt(const crypto_ope_t *ope, int plaintext);

#ifdef CRYPTO_OPE_PRIVATE
STATIC crypto_cipher_t *ope_get_cipher(const crypto_ope_t *ope,
                                       uint32_t initial_idx);
STATIC uint64_t sum_values_from_cipher(crypto_cipher_t *c, size_t n);
#endif

#endif