crypt.h

/*
 * Copyright (C) 2015-2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#pragma once

#include <stdint.h>

#define DEBUG_MAC_VALUES 0

struct key {
    uint8_t byte[32];
};

struct mac {
    uint8_t byte[16];
};

struct iv {
    uint8_t byte[16];
};
#define IV_INITIAL_ZERO_VALUE(iv) \
    {                             \
        { 0 }                     \
    }

#if DEBUG_MAC_VALUES
#define UINT8_16_PRINTF_STR \
    "%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x"
#define UINT8_16_PRINTF_ARGS(var)                                           \
    var[0], var[1], var[2], var[3], var[4], var[5], var[6], var[7], var[8], \
            var[9], var[10], var[11], var[12], var[13], var[14], var[15]
#else
#define UINT8_16_PRINTF_STR "%c"
#define UINT8_16_PRINTF_ARGS(var) '*'
#endif

#define MAC_PRINTF_STR UINT8_16_PRINTF_STR
#define MAC_PRINTF_ARGS(var) UINT8_16_PRINTF_ARGS((var)->byte)
#define IV_PRINTF_STR UINT8_16_PRINTF_STR
#define IV_PRINTF_ARGS(var) UINT8_16_PRINTF_ARGS((var)->byte)

uint64_t str_hash(const char* str);

int calculate_mac(const struct key* key,
                  struct mac* mac,
                  const void* data,
                  size_t data_size);

int generate_iv(struct iv* iv_out);

int encrypt(const struct key* key,
            void* data_in_out,
            size_t data_size,
            const struct iv* iv_in);

int decrypt(const struct key* key,
            void* data_in_out,
            size_t data_size,
            const struct iv* iv_in);

void crypt_init(void);

void crypt_shutdown(void);