library/aria.c

/*
 *  ARIA implementation
 *
 *  Copyright (C) 2006-2017, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  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.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */


#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif

#if defined(MBEDTLS_ARIA_C)

#include "mbedtls/aria.h"

#include <string.h>

#if defined(MBEDTLS_SELF_TEST)
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif /* MBEDTLS_PLATFORM_C */
#endif /* MBEDTLS_SELF_TEST */

#if !defined(MBEDTLS_ARIA_ALT)

// 32-bit integer manipulation macros (little endian)

#ifndef GET_UINT32_LE
#define GET_UINT32_LE(n,b,i)                    \
{                                               \
    (n) = ( (uint32_t) (b)[(i)    ]       )     \
        | ( (uint32_t) (b)[(i) + 1] <<  8 )     \
        | ( (uint32_t) (b)[(i) + 2] << 16 )     \
        | ( (uint32_t) (b)[(i) + 3] << 24 );    \
}
#endif

#ifndef PUT_UINT32_LE
#define PUT_UINT32_LE(n,b,i)                                    \
{                                                               \
    (b)[(i)    ] = (unsigned char) ( ( (n)       ) & 0xFF );    \
    (b)[(i) + 1] = (unsigned char) ( ( (n) >>  8 ) & 0xFF );    \
    (b)[(i) + 2] = (unsigned char) ( ( (n) >> 16 ) & 0xFF );    \
    (b)[(i) + 3] = (unsigned char) ( ( (n) >> 24 ) & 0xFF );    \
}
#endif

// FLIP1 modifies byte order ( A B C D ) -> ( C D A B ), i.e. rotate by 16 bits
#define ARIA_FLIP1(x) (((x) >> 16) ^ ((x) << 16))

// FLIP2 modifies byte order ( A B C D ) -> ( B A D C ), swap pairs of bytes
#define ARIA_FLIP2(x) ((((x) >> 8) & 0x00FF00FF) ^ (((x) & 0x00FF00FF) << 8))

// Affine Transform A
// (ra, rb, rc, rd) = state in/out
// (ta, tb, tc)     = temporary variables

#define ARIA_A( ra, rb, rc, rd, ta, tb, tc ) {  \
    ta  =   rb;                         \
    rb  =   ra;                         \
    ra  =   ARIA_FLIP1( ta );           \
    tb  =   ARIA_FLIP1( rd );           \
    rd  =   ARIA_FLIP2( rc );           \
    rc  =   ARIA_FLIP2( tb );           \
    ta  ^=  rd;                         \
    tc  =   ARIA_FLIP1( rb );           \
    ta  =   ARIA_FLIP2( ta ) ^ tc ^ rc; \
    tb  ^=  ARIA_FLIP1( rd );           \
    tc  ^=  ARIA_FLIP2( ra );           \
    rb  ^=  ta ^ tb;                    \
    tb  =   ARIA_FLIP1( tb ) ^ ta;      \
    ra  ^=  ARIA_FLIP2( tb );           \
    ta  =   ARIA_FLIP1( ta );           \
    rd  ^=  ARIA_FLIP2( ta ) ^ tc;      \
    tc  =   ARIA_FLIP1( tc );           \
    rc  ^=  ARIA_FLIP2( tc ) ^ ta;      \
}


// ARIA Round function ( Substitution Layer SLx + Affine Transform A )
// (ra, rb, rc, rd) = state in/out
// (sa, sb, sc, sd) = 256 8-bit S-Boxes
// (ta, tb, tc)     = temporary variables

#define ARIA_SLA( ra, rb, rc, rd, sa, sb, sc, sd, ta, tb, tc ) { \
    ta  =   ( (uint32_t) sc[(rb >> 16) & 0xFF]) ^           \
            (((uint32_t) sd[ rb >> 24]) << 8)   ^           \
            (((uint32_t) sa[ rb & 0xFF]) << 16) ^           \
            (((uint32_t) sb[(rb >> 8) & 0xFF]) << 24);      \
    rb  =   ( (uint32_t) sa[ ra & 0xFF]) ^                  \
            (((uint32_t) sb[(ra >> 8) & 0xFF]) << 8) ^      \
            (((uint32_t) sc[(ra >> 16) & 0xFF]) << 16) ^    \
            (((uint32_t) sd[ ra >> 24]) << 24);             \
    ra  =   ta;                                             \
    ta  =   ( (uint32_t) sd[ rd >> 24]) ^                   \
            (((uint32_t) sc[(rd >> 16) & 0xFF]) << 8) ^     \
            (((uint32_t) sb[(rd >> 8) & 0xFF]) << 16) ^     \
            (((uint32_t) sa[ rd & 0xFF]) << 24);            \
    rd  =   ( (uint32_t) sb[(rc >> 8) & 0xFF]) ^            \
            (((uint32_t) sa[ rc & 0xFF]) << 8) ^            \
            (((uint32_t) sd[ rc >> 24]) << 16) ^            \
            (((uint32_t) sc[(rc >> 16) & 0xFF]) << 24);     \
    rc  =   ta;                                             \
    ta  =   ARIA_FLIP1( ra ) ^ rd;                          \
    tc  =   ARIA_FLIP1( rb );                               \
    ta  =   ARIA_FLIP2( ta ) ^ tc ^ rc;                     \
    tb  =   ARIA_FLIP2( rc ) ^ ARIA_FLIP1( rd );            \
    tc  ^=  ARIA_FLIP2( ra );                               \
    rb  ^=  ta^ tb;                                         \
    tb  =   ARIA_FLIP1( tb ) ^ ta;                          \
    ra  ^=  ARIA_FLIP2( tb );                               \
    ta  =   ARIA_FLIP1( ta );                               \
    rd  ^=  ARIA_FLIP2( ta ) ^ tc;                          \
    tc  =   ARIA_FLIP1( tc );                               \
    rc  ^=  ARIA_FLIP2( tc ) ^ ta;                          \
}

// S-Boxes

static const uint8_t aria_sb1[0x100] =
{
    0x63, 0x7C, 0x77, 0x7B, 0xF2, 0x6B, 0x6F, 0xC5, 0x30, 0x01, 0x67, 0x2B,
    0xFE, 0xD7, 0xAB, 0x76, 0xCA, 0x82, 0xC9, 0x7D, 0xFA, 0x59, 0x47, 0xF0,
    0xAD, 0xD4, 0xA2, 0xAF, 0x9C, 0xA4, 0x72, 0xC0, 0xB7, 0xFD, 0x93, 0x26,
    0x36, 0x3F, 0xF7, 0xCC, 0x34, 0xA5, 0xE5, 0xF1, 0x71, 0xD8, 0x31, 0x15,
    0x04, 0xC7, 0x23, 0xC3, 0x18, 0x96, 0x05, 0x9A, 0x07, 0x12, 0x80, 0xE2,
    0xEB, 0x27, 0xB2, 0x75, 0x09, 0x83, 0x2C, 0x1A, 0x1B, 0x6E, 0x5A, 0xA0,
    0x52, 0x3B, 0xD6, 0xB3, 0x29, 0xE3, 0x2F, 0x84, 0x53, 0xD1, 0x00, 0xED,
    0x20, 0xFC, 0xB1, 0x5B, 0x6A, 0xCB, 0xBE, 0x39, 0x4A, 0x4C, 0x58, 0xCF,
    0xD0, 0xEF, 0xAA, 0xFB, 0x43, 0x4D, 0x33, 0x85, 0x45, 0xF9, 0x02, 0x7F,
    0x50, 0x3C, 0x9F, 0xA8, 0x51, 0xA3, 0x40, 0x8F, 0x92, 0x9D, 0x38, 0xF5,
    0xBC, 0xB6, 0xDA, 0x21, 0x10, 0xFF, 0xF3, 0xD2, 0xCD, 0x0C, 0x13, 0xEC,
    0x5F, 0x97, 0x44, 0x17, 0xC4, 0xA7, 0x7E, 0x3D, 0x64, 0x5D, 0x19, 0x73,
    0x60, 0x81, 0x4F, 0xDC, 0x22, 0x2A, 0x90, 0x88, 0x46, 0xEE, 0xB8, 0x14,
    0xDE, 0x5E, 0x0B, 0xDB, 0xE0, 0x32, 0x3A, 0x0A, 0x49, 0x06, 0x24, 0x5C,
    0xC2, 0xD3, 0xAC, 0x62, 0x91, 0x95, 0xE4, 0x79, 0xE7, 0xC8, 0x37, 0x6D,
    0x8D, 0xD5, 0x4E, 0xA9, 0x6C, 0x56, 0xF4, 0xEA, 0x65, 0x7A, 0xAE, 0x08,
    0xBA, 0x78, 0x25, 0x2E, 0x1C, 0xA6, 0xB4, 0xC6, 0xE8, 0xDD, 0x74, 0x1F,
    0x4B, 0xBD, 0x8B, 0x8A, 0x70, 0x3E, 0xB5, 0x66, 0x48, 0x03, 0xF6, 0x0E,
    0x61, 0x35, 0x57, 0xB9, 0x86, 0xC1, 0x1D, 0x9E, 0xE1, 0xF8, 0x98, 0x11,
    0x69, 0xD9, 0x8E, 0x94, 0x9B, 0x1E, 0x87, 0xE9, 0xCE, 0x55, 0x28, 0xDF,
    0x8C, 0xA1, 0x89, 0x0D, 0xBF, 0xE6, 0x42, 0x68, 0x41, 0x99, 0x2D, 0x0F,
    0xB0, 0x54, 0xBB, 0x16
};

static const uint8_t aria_sb2[0x100] =
{
    0xE2, 0x4E, 0x54, 0xFC, 0x94, 0xC2, 0x4A, 0xCC, 0x62, 0x0D, 0x6A, 0x46,
    0x3C, 0x4D, 0x8B, 0xD1, 0x5E, 0xFA, 0x64, 0xCB, 0xB4, 0x97, 0xBE, 0x2B,
    0xBC, 0x77, 0x2E, 0x03, 0xD3, 0x19, 0x59, 0xC1, 0x1D, 0x06, 0x41, 0x6B,
    0x55, 0xF0, 0x99, 0x69, 0xEA, 0x9C, 0x18, 0xAE, 0x63, 0xDF, 0xE7, 0xBB,
    0x00, 0x73, 0x66, 0xFB, 0x96, 0x4C, 0x85, 0xE4, 0x3A, 0x09, 0x45, 0xAA,
    0x0F, 0xEE, 0x10, 0xEB, 0x2D, 0x7F, 0xF4, 0x29, 0xAC, 0xCF, 0xAD, 0x91,
    0x8D, 0x78, 0xC8, 0x95, 0xF9, 0x2F, 0xCE, 0xCD, 0x08, 0x7A, 0x88, 0x38,
    0x5C, 0x83, 0x2A, 0x28, 0x47, 0xDB, 0xB8, 0xC7, 0x93, 0xA4, 0x12, 0x53,
    0xFF, 0x87, 0x0E, 0x31, 0x36, 0x21, 0x58, 0x48, 0x01, 0x8E, 0x37, 0x74,
    0x32, 0xCA, 0xE9, 0xB1, 0xB7, 0xAB, 0x0C, 0xD7, 0xC4, 0x56, 0x42, 0x26,
    0x07, 0x98, 0x60, 0xD9, 0xB6, 0xB9, 0x11, 0x40, 0xEC, 0x20, 0x8C, 0xBD,
    0xA0, 0xC9, 0x84, 0x04, 0x49, 0x23, 0xF1, 0x4F, 0x50, 0x1F, 0x13, 0xDC,
    0xD8, 0xC0, 0x9E, 0x57, 0xE3, 0xC3, 0x7B, 0x65, 0x3B, 0x02, 0x8F, 0x3E,
    0xE8, 0x25, 0x92, 0xE5, 0x15, 0xDD, 0xFD, 0x17, 0xA9, 0xBF, 0xD4, 0x9A,
    0x7E, 0xC5, 0x39, 0x67, 0xFE, 0x76, 0x9D, 0x43, 0xA7, 0xE1, 0xD0, 0xF5,
    0x68, 0xF2, 0x1B, 0x34, 0x70, 0x05, 0xA3, 0x8A, 0xD5, 0x79, 0x86, 0xA8,
    0x30, 0xC6, 0x51, 0x4B, 0x1E, 0xA6, 0x27, 0xF6, 0x35, 0xD2, 0x6E, 0x24,
    0x16, 0x82, 0x5F, 0xDA, 0xE6, 0x75, 0xA2, 0xEF, 0x2C, 0xB2, 0x1C, 0x9F,
    0x5D, 0x6F, 0x80, 0x0A, 0x72, 0x44, 0x9B, 0x6C, 0x90, 0x0B, 0x5B, 0x33,
    0x7D, 0x5A, 0x52, 0xF3, 0x61, 0xA1, 0xF7, 0xB0, 0xD6, 0x3F, 0x7C, 0x6D,
    0xED, 0x14, 0xE0, 0xA5, 0x3D, 0x22, 0xB3, 0xF8, 0x89, 0xDE, 0x71, 0x1A,
    0xAF, 0xBA, 0xB5, 0x81
};

static const uint8_t aria_is1[0x100] =
{
    0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E,
    0x81, 0xF3, 0xD7, 0xFB, 0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87,
    0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB, 0x54, 0x7B, 0x94, 0x32,
    0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E,
    0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49,
    0x6D, 0x8B, 0xD1, 0x25, 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16,
    0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92, 0x6C, 0x70, 0x48, 0x50,
    0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84,
    0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05,
    0xB8, 0xB3, 0x45, 0x06, 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02,
    0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, 0x3A, 0x91, 0x11, 0x41,
    0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73,
    0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8,
    0x1C, 0x75, 0xDF, 0x6E, 0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89,
    0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, 0xFC, 0x56, 0x3E, 0x4B,
    0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4,
    0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59,
    0x27, 0x80, 0xEC, 0x5F, 0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D,
    0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF, 0xA0, 0xE0, 0x3B, 0x4D,
    0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61,
    0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63,
    0x55, 0x21, 0x0C, 0x7D
};

static const uint8_t aria_is2[0x100] =
{
    0x30, 0x68, 0x99, 0x1B, 0x87, 0xB9, 0x21, 0x78, 0x50, 0x39, 0xDB, 0xE1,
    0x72, 0x09, 0x62, 0x3C, 0x3E, 0x7E, 0x5E, 0x8E, 0xF1, 0xA0, 0xCC, 0xA3,
    0x2A, 0x1D, 0xFB, 0xB6, 0xD6, 0x20, 0xC4, 0x8D, 0x81, 0x65, 0xF5, 0x89,
    0xCB, 0x9D, 0x77, 0xC6, 0x57, 0x43, 0x56, 0x17, 0xD4, 0x40, 0x1A, 0x4D,
    0xC0, 0x63, 0x6C, 0xE3, 0xB7, 0xC8, 0x64, 0x6A, 0x53, 0xAA, 0x38, 0x98,
    0x0C, 0xF4, 0x9B, 0xED, 0x7F, 0x22, 0x76, 0xAF, 0xDD, 0x3A, 0x0B, 0x58,
    0x67, 0x88, 0x06, 0xC3, 0x35, 0x0D, 0x01, 0x8B, 0x8C, 0xC2, 0xE6, 0x5F,
    0x02, 0x24, 0x75, 0x93, 0x66, 0x1E, 0xE5, 0xE2, 0x54, 0xD8, 0x10, 0xCE,
    0x7A, 0xE8, 0x08, 0x2C, 0x12, 0x97, 0x32, 0xAB, 0xB4, 0x27, 0x0A, 0x23,
    0xDF, 0xEF, 0xCA, 0xD9, 0xB8, 0xFA, 0xDC, 0x31, 0x6B, 0xD1, 0xAD, 0x19,
    0x49, 0xBD, 0x51, 0x96, 0xEE, 0xE4, 0xA8, 0x41, 0xDA, 0xFF, 0xCD, 0x55,
    0x86, 0x36, 0xBE, 0x61, 0x52, 0xF8, 0xBB, 0x0E, 0x82, 0x48, 0x69, 0x9A,
    0xE0, 0x47, 0x9E, 0x5C, 0x04, 0x4B, 0x34, 0x15, 0x79, 0x26, 0xA7, 0xDE,
    0x29, 0xAE, 0x92, 0xD7, 0x84, 0xE9, 0xD2, 0xBA, 0x5D, 0xF3, 0xC5, 0xB0,
    0xBF, 0xA4, 0x3B, 0x71, 0x44, 0x46, 0x2B, 0xFC, 0xEB, 0x6F, 0xD5, 0xF6,
    0x14, 0xFE, 0x7C, 0x70, 0x5A, 0x7D, 0xFD, 0x2F, 0x18, 0x83, 0x16, 0xA5,
    0x91, 0x1F, 0x05, 0x95, 0x74, 0xA9, 0xC1, 0x5B, 0x4A, 0x85, 0x6D, 0x13,
    0x07, 0x4F, 0x4E, 0x45, 0xB2, 0x0F, 0xC9, 0x1C, 0xA6, 0xBC, 0xEC, 0x73,
    0x90, 0x7B, 0xCF, 0x59, 0x8F, 0xA1, 0xF9, 0x2D, 0xF2, 0xB1, 0x00, 0x94,
    0x37, 0x9F, 0xD0, 0x2E, 0x9C, 0x6E, 0x28, 0x3F, 0x80, 0xF0, 0x3D, 0xD3,
    0x25, 0x8A, 0xB5, 0xE7, 0x42, 0xB3, 0xC7, 0xEA, 0xF7, 0x4C, 0x11, 0x33,
    0x03, 0xA2, 0xAC, 0x60
};
// FO and FE are helpers for key schedule

// r = FO( p, k ) ^ x

static void aria_fo( uint32_t r[4],
    const uint32_t p[4], const uint32_t k[4], const uint32_t x[4] )
{
    uint32_t a, b, c, d;
    uint32_t t, u, v;

    a = p[0] ^ k[0];
    b = p[1] ^ k[1];
    c = p[2] ^ k[2];
    d = p[3] ^ k[3];

    ARIA_SLA( a, b, c, d, aria_sb1, aria_sb2, aria_is1, aria_is2, t, u, v );

    r[0] = a ^ x[0];
    r[1] = b ^ x[1];
    r[2] = c ^ x[2];
    r[3] = d ^ x[3];
}

// r = FE( p, k ) ^ x

static void aria_fe(uint32_t r[4],
    const uint32_t p[4], const uint32_t k[4], const uint32_t x[4] )
{
    uint32_t a, b, c, d;
    uint32_t t, u, v;

    a = p[0] ^ k[0];
    b = p[1] ^ k[1];
    c = p[2] ^ k[2];
    d = p[3] ^ k[3];

    ARIA_SLA( a, b, c, d, aria_is1, aria_is2, aria_sb1, aria_sb2, t, u, v );

    r[0] = a ^ x[0];
    r[1] = b ^ x[1];
    r[2] = c ^ x[2];
    r[3] = d ^ x[3];
}

// Big endian 128-bit rotation: d = a ^ (b <<< n), used only in key setup.
// This is relatively slow since our implementation is geared towards
// little-endian targets and stores state in that order.

static void aria_rot128(uint32_t r[4], const uint32_t a[4],
                        const uint32_t b[4], int n)
{
    int i, j, n1, n2;
    uint32_t t, u;

    j = (n >> 5) & 3;                       // word offset
    n1 = n & 0x1F;                          // bit offsets
    n2 = 32 - n1;                           // n1 should be nonzero!
    t = ARIA_FLIP1( ARIA_FLIP2( b[j] ) );   // big endian
    for( i = 0; i < 4; i++ )
    {
        j = (j + 1) & 3;                    // get next word, big endian
        u = ARIA_FLIP1( ARIA_FLIP2( b[j] ) );
        t <<= n1;                           // rotate
        if (n2 < 32)                        // intel rotate 32 bits = 0 bits..
            t |= u >> n2;
        t = ARIA_FLIP1( ARIA_FLIP2( t ) );  // back to little endian
        r[i] = a[i] ^ t;                    // store
        t = u;                              // move to next word
    }
}

// Set encryption key

int mbedtls_aria_setkey_enc(mbedtls_aria_context *ctx,
                            const unsigned char *key, unsigned int keybits)
{
    // round constant masks
    const uint32_t rc[3][4] =
    {
        {   0xB7C17C51, 0x940A2227, 0xE8AB13FE, 0xE06E9AFA  },
        {   0xCC4AB16D, 0x20C8219E, 0xD5B128FF, 0xB0E25DEF  },
        {   0x1D3792DB, 0x70E92621, 0x75972403, 0x0EC9E804  }
    };

    int i;
    uint32_t w[4][4], *w2;

    if (keybits != 128 && keybits != 192 && keybits != 256)
        return MBEDTLS_ERR_ARIA_INVALID_KEY_LENGTH;

    // W0 = KL
    GET_UINT32_LE( w[0][0], key,  0 );      // copy key to W0 | W1
    GET_UINT32_LE( w[0][1], key,  4 );
    GET_UINT32_LE( w[0][2], key,  8 );
    GET_UINT32_LE( w[0][3], key, 12 );

    memset(w[1], 0, 16);
    if( keybits >= 192 )
    {
        GET_UINT32_LE( w[1][0], key, 16 );  // 192 bit key
        GET_UINT32_LE( w[1][1], key, 20 );
    }
    if( keybits == 256 )
    {
        GET_UINT32_LE( w[1][2], key, 24 );  // 256 bit key
        GET_UINT32_LE( w[1][3], key, 28 );
    }

    i = (keybits - 128) >> 6;               // index: 0, 1, 2
    ctx->nr = 12 + 2 * i;                   // no. rounds: 12, 14, 16

    aria_fo( w[1], w[0], rc[i], w[1] );     // W1 = FO(W0, CK1) ^ KR
    i = i < 2 ? i + 1 : 0;
    aria_fe( w[2], w[1], rc[i], w[0] );     // W2 = FE(W1, CK2) ^ W0
    i = i < 2 ? i + 1 : 0;
    aria_fo( w[3], w[2], rc[i], w[1] );     // W3 = FO(W2, CK3) ^ W1

    for( i = 0; i < 4; i++ )                // create round keys
    {
        w2 = w[(i + 1) & 3];
        aria_rot128( ctx->rk[i     ], w[i], w2, -19);
        aria_rot128( ctx->rk[i +  4], w[i], w2, -31);
        aria_rot128( ctx->rk[i +  8], w[i], w2,  61);
        aria_rot128( ctx->rk[i + 12], w[i], w2,  31);
    }
    aria_rot128( ctx->rk[16], w[0], w[1], 19 );

    return 0;
}

// Set decryption key

int mbedtls_aria_setkey_dec(mbedtls_aria_context *ctx,
                            const unsigned char *key, unsigned int keybits)
{
    int i, j, k, ret;
    uint32_t t, u, v;

    ret = mbedtls_aria_setkey_enc( ctx, key, keybits );
    if( ret != 0 )
        return ret;

    // flip the order of round keys
    for( i = 0, j = ctx->nr; i < j; i++, j-- )
    {
        for( k = 0; k < 4; k++ )
        {
            t = ctx->rk[i][k];
            ctx->rk[i][k] = ctx->rk[j][k];
            ctx->rk[j][k] = t;
        }
    }

    // apply affine transform to middle keys
    for (i = 1; i < ctx->nr; i++ )
    {
        ARIA_A( ctx->rk[i][0], ctx->rk[i][1], ctx->rk[i][2], ctx->rk[i][3],
            t, u, v );
    }

    return 0;
}

// Encrypt a block

int mbedtls_aria_crypt_ecb( mbedtls_aria_context *ctx,
                            int mode,
                            const unsigned char input[16],
                            unsigned char output[16] )
{
    int i;

    uint32_t a, b, c, d;
    uint32_t t, u, v;

    ( (void) mode );

    GET_UINT32_LE( a, input,  0 );
    GET_UINT32_LE( b, input,  4 );
    GET_UINT32_LE( c, input,  8 );
    GET_UINT32_LE( d, input, 12 );

    i = 0;
    while (1)
    {
        a ^= ctx->rk[i][0];
        b ^= ctx->rk[i][1];
        c ^= ctx->rk[i][2];
        d ^= ctx->rk[i][3];
        i++;
        ARIA_SLA( a, b, c, d,
            aria_sb1, aria_sb2, aria_is1, aria_is2, t, u, v );

        a ^= ctx->rk[i][0];
        b ^= ctx->rk[i][1];
        c ^= ctx->rk[i][2];
        d ^= ctx->rk[i][3];
        i++;
        if (i >= ctx->nr)
            break;

        ARIA_SLA( a, b, c, d,
            aria_is1, aria_is2, aria_sb1, aria_sb2, t, u, v );
    }

    // final substitution

    a = ctx->rk[i][0] ^
        ( (uint32_t) aria_is1[ a        & 0xFF])        ^
        (((uint32_t) aria_is2[(a >>  8) & 0xFF]) <<  8) ^
        (((uint32_t) aria_sb1[(a >> 16) & 0xFF]) << 16) ^
        (((uint32_t) aria_sb2[ a >> 24        ]) << 24);

    b = ctx->rk[i][1] ^
        ( (uint32_t) aria_is1[ b        & 0xFF])        ^
        (((uint32_t) aria_is2[(b >>  8) & 0xFF]) <<  8) ^
        (((uint32_t) aria_sb1[(b >> 16) & 0xFF]) << 16) ^
        (((uint32_t) aria_sb2[ b >> 24        ]) << 24);

    c = ctx->rk[i][2] ^
        ( (uint32_t) aria_is1[ c        & 0xFF])        ^
        (((uint32_t) aria_is2[(c >>  8) & 0xFF]) <<  8) ^
        (((uint32_t) aria_sb1[(c >> 16) & 0xFF]) << 16) ^
        (((uint32_t) aria_sb2[ c >> 24        ]) << 24);

    d = ctx->rk[i][3] ^
        ( (uint32_t) aria_is1[ d        & 0xFF])        ^
        (((uint32_t) aria_is2[(d >>  8) & 0xFF]) <<  8) ^
        (((uint32_t) aria_sb1[(d >> 16) & 0xFF]) << 16) ^
        (((uint32_t) aria_sb2[ d >> 24        ]) << 24);

    PUT_UINT32_LE( a, output,  0 );
    PUT_UINT32_LE( b, output,  4 );
    PUT_UINT32_LE( c, output,  8 );
    PUT_UINT32_LE( d, output, 12 );

    return 0;
}



#if defined(MBEDTLS_CIPHER_MODE_CBC)
/*
 * ARIA-CBC buffer encryption/decryption
 */
int mbedtls_aria_crypt_cbc( mbedtls_aria_context *ctx,
                    int mode,
                    size_t length,
                    unsigned char iv[16],
                    const unsigned char *input,
                    unsigned char *output )
{
    int i;
    unsigned char temp[16];

    if( length % 16 )
        return( MBEDTLS_ERR_ARIA_INVALID_INPUT_LENGTH );

    if( mode == MBEDTLS_ARIA_DECRYPT )
    {
        while( length > 0 )
        {
            memcpy( temp, input, 16 );
            mbedtls_aria_crypt_ecb( ctx, mode, input, output );

            for( i = 0; i < 16; i++ )
                output[i] = (unsigned char)( output[i] ^ iv[i] );

            memcpy( iv, temp, 16 );

            input  += 16;
            output += 16;
            length -= 16;
        }
    }
    else
    {
        while( length > 0 )
        {
            for( i = 0; i < 16; i++ )
                output[i] = (unsigned char)( input[i] ^ iv[i] );

            mbedtls_aria_crypt_ecb( ctx, mode, output, output );
            memcpy( iv, output, 16 );

            input  += 16;
            output += 16;
            length -= 16;
        }
    }

    return( 0 );
}
#endif /* MBEDTLS_CIPHER_MODE_CBC */

#if defined(MBEDTLS_CIPHER_MODE_CFB)
/*
 * ARIA-CFB128 buffer encryption/decryption
 */
int mbedtls_aria_crypt_cfb128( mbedtls_aria_context *ctx,
                       int mode,
                       size_t length,
                       size_t *iv_off,
                       unsigned char iv[16],
                       const unsigned char *input,
                       unsigned char *output )
{
    int c;
    size_t n = *iv_off;

    if( mode == MBEDTLS_ARIA_DECRYPT )
    {
        while( length-- )
        {
            if( n == 0 )
                mbedtls_aria_crypt_ecb( ctx, MBEDTLS_ARIA_ENCRYPT, iv, iv );

            c = *input++;
            *output++ = (unsigned char)( c ^ iv[n] );
            iv[n] = (unsigned char) c;

            n = ( n + 1 ) & 0x0F;
        }
    }
    else
    {
        while( length-- )
        {
            if( n == 0 )
                mbedtls_aria_crypt_ecb( ctx, MBEDTLS_ARIA_ENCRYPT, iv, iv );

            iv[n] = *output++ = (unsigned char)( iv[n] ^ *input++ );

            n = ( n + 1 ) & 0x0F;
        }
    }

    *iv_off = n;

    return( 0 );
}
#endif /* MBEDTLS_CIPHER_MODE_CFB */

#if defined(MBEDTLS_CIPHER_MODE_CTR)
/*
 * ARIA-CTR buffer encryption/decryption
 */
int mbedtls_aria_crypt_ctr( mbedtls_aria_context *ctx,
                       size_t length,
                       size_t *nc_off,
                       unsigned char nonce_counter[16],
                       unsigned char stream_block[16],
                       const unsigned char *input,
                       unsigned char *output )
{
    int c, i;
    size_t n = *nc_off;

    while( length-- )
    {
        if( n == 0 ) {
            mbedtls_aria_crypt_ecb( ctx, MBEDTLS_ARIA_ENCRYPT, nonce_counter,
                                stream_block );

            for( i = 16; i > 0; i-- )
                if( ++nonce_counter[i - 1] != 0 )
                    break;
        }
        c = *input++;
        *output++ = (unsigned char)( c ^ stream_block[n] );

        n = ( n + 1 ) & 0x0F;
    }

    *nc_off = n;

    return( 0 );
}
#endif /* MBEDTLS_CIPHER_MODE_CTR */
#endif /* !MBEDTLS_ARIA_ALT */

#if defined(MBEDTLS_SELF_TEST)

/*
 * Checkup routine
 */

int mbedtls_aria_self_test( int verbose )
{
    // ECB test vectors from RFC 5794

    const uint8_t aria_ecb_test_key[32] =                       // test key
    {
        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,         // 128 bit
        0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,         // 192 bit
        0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F          // 256 bit
    };
    const uint8_t aria_ecb_test_pt[16] =                        // plaintext
    {
        0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,         // same for all
        0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF          // key sizes
    };
    const uint8_t aria_ecb_test_ct[3][16] =                     // ciphertext
    {
        {   0xD7, 0x18, 0xFB, 0xD6, 0xAB, 0x64, 0x4C, 0x73,     // 128 bit
            0x9D, 0xA9, 0x5F, 0x3B, 0xE6, 0x45, 0x17, 0x78  }
        ,
        {   0x26, 0x44, 0x9C, 0x18, 0x05, 0xDB, 0xE7, 0xAA,     // 192 bit
            0x25, 0xA4, 0x68, 0xCE, 0x26, 0x3A, 0x9E, 0x79 }
        ,
        {   0xF9, 0x2B, 0xD7, 0xC7, 0x9F, 0xB7, 0x2E, 0x2F,     // 256 bit
            0x2B, 0x8F, 0x80, 0xC1, 0x97, 0x2D, 0x24, 0xFC  }
    };

    int i;
    uint8_t blk[16];
    mbedtls_aria_context ctx;

    for( i = 0; i < 3; i++ )
    {
        // test encryption
        if( verbose )
            printf( "  ARIA-ECB-%d (enc): ", 128 + 64 * i);

        mbedtls_aria_setkey_enc( &ctx, aria_ecb_test_key, 128 + 64 * i );
        mbedtls_aria_crypt_ecb( &ctx, MBEDTLS_ARIA_ENCRYPT,
            aria_ecb_test_pt, blk );

        if( memcmp( blk, aria_ecb_test_ct[i], 16 ) != 0 )
        {
            if( verbose )
                printf( "failed\n" );
            return( 1 );
        }
        if( verbose )
            printf( "passed\n" );

        // test decryption

        if( verbose )
            printf( "  ARIA-ECB-%d (dec): ", 128 + 64 * i);

        mbedtls_aria_setkey_dec( &ctx, aria_ecb_test_key, 128 + 64 * i );
        mbedtls_aria_crypt_ecb( &ctx, MBEDTLS_ARIA_DECRYPT,
            aria_ecb_test_ct[i], blk );

        if (memcmp( blk, aria_ecb_test_pt, 16 ) != 0)
        {
            if( verbose )
                printf( "failed\n" );
            return( 1 );
        }
        if( verbose )
            printf( "passed\n" );
    }
    printf("\n");

    return( 0 );
}

#endif /* MBEDTLS_SELF_TEST */

#endif /* MBEDTLS_ARIA_C */