/*
 *  Copyright (C) 2021 - This file is part of libecc project
 *
 *  Authors:
 *      Ryad BENADJILA <ryadbenadjila@gmail.com>
 *      Arnaud EBALARD <arnaud.ebalard@ssi.gouv.fr>
 *
 *  This software is licensed under a dual BSD and GPL v2 license.
 *  See LICENSE file at the root folder of the project.
 */

#ifndef __TDES_H__
#define __TDES_H__

/* Include libec for useful types and macros */
#include <libecc/libec.h>

typedef enum {
        DES_ENCRYPTION = 0,
        DES_DECRYPTION = 1,
} des_direction;

/* DES context */
typedef struct {
    des_direction dir;
    u64 sk[16]; /* encryption/decryption subkeys */
} des_context;

/* Triple DES context */
typedef struct {
    des_direction dir;
    des_context des[3];
} des3_context;

/* Odd parity table */
static const u8 odd_parity[256] = {
    1, 1, 2, 2, 4, 4, 7, 7, 8, 8, 11, 11, 13, 13, 14, 14,
    16, 16, 19, 19, 21, 21, 22, 22, 25, 25, 26, 26, 28, 28, 31, 31,
    32, 32, 35, 35, 37, 37, 38, 38, 41, 41, 42, 42, 44, 44, 47, 47,
    49, 49, 50, 50, 52, 52, 55, 55, 56, 56, 59, 59, 61, 61, 62, 62,
    64, 64, 67, 67, 69, 69, 70, 70, 73, 73, 74, 74, 76, 76, 79, 79,
    81, 81, 82, 82, 84, 84, 87, 87, 88, 88, 91, 91, 93, 93, 94, 94,
    97, 97, 98, 98, 100, 100, 103, 103, 104, 104, 107, 107, 109, 109, 110,
    110,
    112, 112, 115, 115, 117, 117, 118, 118, 121, 121, 122, 122, 124, 124, 127,
    127,
    128, 128, 131, 131, 133, 133, 134, 134, 137, 137, 138, 138, 140, 140, 143,
    143,
    145, 145, 146, 146, 148, 148, 151, 151, 152, 152, 155, 155, 157, 157, 158,
    158,
    161, 161, 162, 162, 164, 164, 167, 167, 168, 168, 171, 171, 173, 173, 174,
    174,
    176, 176, 179, 179, 181, 181, 182, 182, 185, 185, 186, 186, 188, 188, 191,
    191,
    193, 193, 194, 194, 196, 196, 199, 199, 200, 200, 203, 203, 205, 205, 206,
    206,
    208, 208, 211, 211, 213, 213, 214, 214, 217, 217, 218, 218, 220, 220, 223,
    223,
    224, 224, 227, 227, 229, 229, 230, 230, 233, 233, 234, 234, 236, 236, 239,
    239,
    241, 241, 242, 242, 244, 244, 247, 247, 248, 248, 251, 251, 253, 253, 254,
    254
};

/* DES key schedule */
ATTRIBUTE_WARN_UNUSED_RET int des_set_key(des_context *ctx, const u8 k[8], des_direction dir);

/* DES encryption/decryption */
ATTRIBUTE_WARN_UNUSED_RET int des(const des_context *ctx, const u8 input[8], u8 output[8]);

/* TDES key schedules */
ATTRIBUTE_WARN_UNUSED_RET int des3_set_keys(des3_context *ctx, const u8 k1[8], const u8 k2[8], const u8 k3[8], des_direction dir);

/* TDES encryption/decryption */
ATTRIBUTE_WARN_UNUSED_RET int des3(const des3_context *ctx, const u8 input[8], u8 output[8]);

#endif /* __TDES_H__ */