/*
 *  Camellia implementation
 *
 *  Copyright (C) 2006-2010, Brainspark B.V.
 *
 *  This file is part of PolarSSL (http://www.polarssl.org)
 *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
 *
 *  All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
/*
 *  The Camellia block cipher was designed by NTT and Mitsubishi Electric
 *  Corporation.
 *
 *  http://info.isl.ntt.co.jp/crypt/eng/camellia/dl/01espec.pdf
 */

#include "polarssl/config.h"

#if defined(POLARSSL_CAMELLIA_C)

#include "polarssl/camellia.h"

/*
 * 32-bit integer manipulation macros (big endian)
 */
#ifndef GET_ULONG_BE
#define GET_ULONG_BE(n,b,i)                             \
{                                                       \
    (n) = ( (unsigned long) (b)[(i)    ] << 24 )        \
        | ( (unsigned long) (b)[(i) + 1] << 16 )        \
        | ( (unsigned long) (b)[(i) + 2] <<  8 )        \
        | ( (unsigned long) (b)[(i) + 3]       );       \
}
#endif

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

static const unsigned char SIGMA_CHARS[6][8] =
{
    { 0xa0, 0x9e, 0x66, 0x7f, 0x3b, 0xcc, 0x90, 0x8b },
    { 0xb6, 0x7a, 0xe8, 0x58, 0x4c, 0xaa, 0x73, 0xb2 },
    { 0xc6, 0xef, 0x37, 0x2f, 0xe9, 0x4f, 0x82, 0xbe },
    { 0x54, 0xff, 0x53, 0xa5, 0xf1, 0xd3, 0x6f, 0x1c },
    { 0x10, 0xe5, 0x27, 0xfa, 0xde, 0x68, 0x2d, 0x1d },
    { 0xb0, 0x56, 0x88, 0xc2, 0xb3, 0xe6, 0xc1, 0xfd }
};

#ifdef POLARSSL_CAMELLIA_SMALL_MEMORY

static const unsigned char FSb[256] =
{
    112,130, 44,236,179, 39,192,229,228,133, 87, 53,234, 12,174, 65,
     35,239,107,147, 69, 25,165, 33,237, 14, 79, 78, 29,101,146,189,
    134,184,175,143,124,235, 31,206, 62, 48,220, 95, 94,197, 11, 26,
    166,225, 57,202,213, 71, 93, 61,217,  1, 90,214, 81, 86,108, 77,
    139, 13,154,102,251,204,176, 45,116, 18, 43, 32,240,177,132,153,
    223, 76,203,194, 52,126,118,  5,109,183,169, 49,209, 23,  4,215,
     20, 88, 58, 97,222, 27, 17, 28, 50, 15,156, 22, 83, 24,242, 34,
    254, 68,207,178,195,181,122,145, 36,  8,232,168, 96,252,105, 80,
    170,208,160,125,161,137, 98,151, 84, 91, 30,149,224,255,100,210,
     16,196,  0, 72,163,247,117,219,138,  3,230,218,  9, 63,221,148,
    135, 92,131,  2,205, 74,144, 51,115,103,246,243,157,127,191,226,
     82,155,216, 38,200, 55,198, 59,129,150,111, 75, 19,190, 99, 46,
    233,121,167,140,159,110,188,142, 41,245,249,182, 47,253,180, 89,
    120,152,  6,106,231, 70,113,186,212, 37,171, 66,136,162,141,250,
    114,  7,185, 85,248,238,172, 10, 54, 73, 42,104, 60, 56,241,164,
     64, 40,211,123,187,201, 67,193, 21,227,173,244,119,199,128,158
};

#define SBOX1(n) FSb[(n)]
#define SBOX2(n) (unsigned char)((FSb[(n)] >> 7 ^ FSb[(n)] << 1) & 0xff)
#define SBOX3(n) (unsigned char)((FSb[(n)] >> 1 ^ FSb[(n)] << 7) & 0xff)
#define SBOX4(n) FSb[((n) << 1 ^ (n) >> 7) &0xff]

#else

static const unsigned char FSb[256] =
{
    112, 130,  44, 236, 179,  39, 192, 229, 228, 133,  87,  53, 234,  12, 174,  65,
    35, 239, 107, 147,  69,  25, 165,  33, 237,  14,  79,  78,  29, 101, 146, 189,
    134, 184, 175, 143, 124, 235,  31, 206,  62,  48, 220,  95,  94, 197,  11,  26,
    166, 225,  57, 202, 213,  71,  93,  61, 217,   1,  90, 214,  81,  86, 108,  77,
    139,  13, 154, 102, 251, 204, 176,  45, 116,  18,  43,  32, 240, 177, 132, 153,
    223,  76, 203, 194,  52, 126, 118,   5, 109, 183, 169,  49, 209,  23,   4, 215,
    20,  88,  58,  97, 222,  27,  17,  28,  50,  15, 156,  22,  83,  24, 242,  34,
    254,  68, 207, 178, 195, 181, 122, 145,  36,   8, 232, 168,  96, 252, 105,  80,
    170, 208, 160, 125, 161, 137,  98, 151,  84,  91,  30, 149, 224, 255, 100, 210,
    16, 196,   0,  72, 163, 247, 117, 219, 138,   3, 230, 218,   9,  63, 221, 148,
    135,  92, 131,   2, 205,  74, 144,  51, 115, 103, 246, 243, 157, 127, 191, 226,
    82, 155, 216,  38, 200,  55, 198,  59, 129, 150, 111,  75,  19, 190,  99,  46,
    233, 121, 167, 140, 159, 110, 188, 142,  41, 245, 249, 182,  47, 253, 180,  89,
    120, 152,   6, 106, 231,  70, 113, 186, 212,  37, 171,  66, 136, 162, 141, 250,
    114,   7, 185,  85, 248, 238, 172,  10,  54,  73,  42, 104,  60,  56, 241, 164,
    64,  40, 211, 123, 187, 201,  67, 193,  21, 227, 173, 244, 119, 199, 128, 158
};

static const unsigned char FSb2[256] =
{
    224,   5,  88, 217, 103,  78, 129, 203, 201,  11, 174, 106, 213,  24,  93, 130,
    70, 223, 214,  39, 138,  50,  75,  66, 219,  28, 158, 156,  58, 202,  37, 123,
    13, 113,  95,  31, 248, 215,  62, 157, 124,  96, 185, 190, 188, 139,  22,  52,
    77, 195, 114, 149, 171, 142, 186, 122, 179,   2, 180, 173, 162, 172, 216, 154,
    23,  26,  53, 204, 247, 153,  97,  90, 232,  36,  86,  64, 225,  99,   9,  51,
    191, 152, 151, 133, 104, 252, 236,  10, 218, 111,  83,  98, 163,  46,   8, 175,
    40, 176, 116, 194, 189,  54,  34,  56, 100,  30,  57,  44, 166,  48, 229,  68,
    253, 136, 159, 101, 135, 107, 244,  35,  72,  16, 209,  81, 192, 249, 210, 160,
    85, 161,  65, 250,  67,  19, 196,  47, 168, 182,  60,  43, 193, 255, 200, 165,
    32, 137,   0, 144,  71, 239, 234, 183,  21,   6, 205, 181,  18, 126, 187,  41,
    15, 184,   7,   4, 155, 148,  33, 102, 230, 206, 237, 231,  59, 254, 127, 197,
    164,  55, 177,  76, 145, 110, 141, 118,   3,  45, 222, 150,  38, 125, 198,  92,
    211, 242,  79,  25,  63, 220, 121,  29,  82, 235, 243, 109,  94, 251, 105, 178,
    240,  49,  12, 212, 207, 140, 226, 117, 169,  74,  87, 132,  17,  69,  27, 245,
    228,  14, 115, 170, 241, 221,  89,  20, 108, 146,  84, 208, 120, 112, 227,  73,
    128,  80, 167, 246, 119, 147, 134, 131,  42, 199,  91, 233, 238, 143,   1,  61
};

static const unsigned char FSb3[256] =
{
    56,  65,  22, 118, 217, 147,  96, 242, 114, 194, 171, 154, 117,   6,  87, 160,
    145, 247, 181, 201, 162, 140, 210, 144, 246,   7, 167,  39, 142, 178,  73, 222,
    67,  92, 215, 199,  62, 245, 143, 103,  31,  24, 110, 175,  47, 226, 133,  13,
    83, 240, 156, 101, 234, 163, 174, 158, 236, 128,  45, 107, 168,  43,  54, 166,
    197, 134,  77,  51, 253, 102,  88, 150,  58,   9, 149,  16, 120, 216,  66, 204,
    239,  38, 229,  97,  26,  63,  59, 130, 182, 219, 212, 152, 232, 139,   2, 235,
    10,  44,  29, 176, 111, 141, 136,  14,  25, 135,  78,  11, 169,  12, 121,  17,
    127,  34, 231,  89, 225, 218,  61, 200,  18,   4, 116,  84,  48, 126, 180,  40,
    85, 104,  80, 190, 208, 196,  49, 203,  42, 173,  15, 202, 112, 255,  50, 105,
    8,  98,   0,  36, 209, 251, 186, 237,  69, 129, 115, 109, 132, 159, 238,  74,
    195,  46, 193,   1, 230,  37,  72, 153, 185, 179, 123, 249, 206, 191, 223, 113,
    41, 205, 108,  19, 100, 155,  99, 157, 192,  75, 183, 165, 137,  95, 177,  23,
    244, 188, 211,  70, 207,  55,  94,  71, 148, 250, 252,  91, 151, 254,  90, 172,
    60,  76,   3,  53, 243,  35, 184,  93, 106, 146, 213,  33,  68,  81, 198, 125,
    57, 131, 220, 170, 124, 119,  86,   5,  27, 164,  21,  52,  30,  28, 248,  82,
    32,  20, 233, 189, 221, 228, 161, 224, 138, 241, 214, 122, 187, 227,  64,  79
};

static const unsigned char FSb4[256] =
{
    112,  44, 179, 192, 228,  87, 234, 174,  35, 107,  69, 165, 237,  79,  29, 146,
    134, 175, 124,  31,  62, 220,  94,  11, 166,  57, 213,  93, 217,  90,  81, 108,
    139, 154, 251, 176, 116,  43, 240, 132, 223, 203,  52, 118, 109, 169, 209,   4,
    20,  58, 222,  17,  50, 156,  83, 242, 254, 207, 195, 122,  36, 232,  96, 105,
    170, 160, 161,  98,  84,  30, 224, 100,  16,   0, 163, 117, 138, 230,   9, 221,
    135, 131, 205, 144, 115, 246, 157, 191,  82, 216, 200, 198, 129, 111,  19,  99,
    233, 167, 159, 188,  41, 249,  47, 180, 120,   6, 231, 113, 212, 171, 136, 141,
    114, 185, 248, 172,  54,  42,  60, 241,  64, 211, 187,  67,  21, 173, 119, 128,
    130, 236,  39, 229, 133,  53,  12,  65, 239, 147,  25,  33,  14,  78, 101, 189,
    184, 143, 235, 206,  48,  95, 197,  26, 225, 202,  71,  61,   1, 214,  86,  77,
    13, 102, 204,  45,  18,  32, 177, 153,  76, 194, 126,   5, 183,  49,  23, 215,
    88,  97,  27,  28,  15,  22,  24,  34,  68, 178, 181, 145,   8, 168, 252,  80,
    208, 125, 137, 151,  91, 149, 255, 210, 196,  72, 247, 219,   3, 218,  63, 148,
    92,   2,  74,  51, 103, 243, 127, 226, 155,  38,  55,  59, 150,  75, 190,  46,
    121, 140, 110, 142, 245, 182, 253,  89, 152, 106,  70, 186,  37,  66, 162, 250,
    7,  85, 238,  10,  73, 104,  56, 164,  40, 123, 201, 193, 227, 244, 199, 158
};

#define SBOX1(n) FSb[(n)]
#define SBOX2(n) FSb2[(n)]
#define SBOX3(n) FSb3[(n)]
#define SBOX4(n) FSb4[(n)]

#endif

static const unsigned char shifts[2][4][4] =
{
    {
        { 1, 1, 1, 1 }, /* KL */
        { 0, 0, 0, 0 }, /* KR */
        { 1, 1, 1, 1 }, /* KA */
        { 0, 0, 0, 0 }  /* KB */
    },
    {
        { 1, 0, 1, 1 }, /* KL */
        { 1, 1, 0, 1 }, /* KR */
        { 1, 1, 1, 0 }, /* KA */
        { 1, 1, 0, 1 }  /* KB */
    }
};

static const signed char indexes[2][4][20] =
{
    {
        {  0,  1,  2,  3,  8,  9, 10, 11, 38, 39,
          36, 37, 23, 20, 21, 22, 27, -1, -1, 26 }, /* KL -> RK */
        { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
          -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 }, /* KR -> RK */
        {  4,  5,  6,  7, 12, 13, 14, 15, 16, 17,
          18, 19, -1, 24, 25, -1, 31, 28, 29, 30 }, /* KA -> RK */
        { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
          -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 }  /* KB -> RK */
    },
    {
        {  0,  1,  2,  3, 61, 62, 63, 60, -1, -1,
          -1, -1, 27, 24, 25, 26, 35, 32, 33, 34 }, /* KL -> RK */
        { -1, -1, -1, -1,  8,  9, 10, 11, 16, 17,
          18, 19, -1, -1, -1, -1, 39, 36, 37, 38 }, /* KR -> RK */
        { -1, -1, -1, -1, 12, 13, 14, 15, 58, 59,
          56, 57, 31, 28, 29, 30, -1, -1, -1, -1 }, /* KA -> RK */
        {  4,  5,  6,  7, 65, 66, 67, 64, 20, 21,
          22, 23, -1, -1, -1, -1, 43, 40, 41, 42 }  /* KB -> RK */
    }
};

static const signed char transposes[2][20] =
{
    {
        21, 22, 23, 20,
        -1, -1, -1, -1,
        18, 19, 16, 17,
        11,  8,  9, 10,
        15, 12, 13, 14
    },
    {
        25, 26, 27, 24,
        29, 30, 31, 28,
        18, 19, 16, 17,
        -1, -1, -1, -1,
        -1, -1, -1, -1
    }
};

/* Shift macro for 128 bit strings with rotation smaller than 32 bits (!) */
#define ROTL(DEST, SRC, SHIFT)                                      \
{                                                                   \
    (DEST)[0] = (SRC)[0] << (SHIFT) ^ (SRC)[1] >> (32 - (SHIFT));   \
    (DEST)[1] = (SRC)[1] << (SHIFT) ^ (SRC)[2] >> (32 - (SHIFT));   \
    (DEST)[2] = (SRC)[2] << (SHIFT) ^ (SRC)[3] >> (32 - (SHIFT));   \
    (DEST)[3] = (SRC)[3] << (SHIFT) ^ (SRC)[0] >> (32 - (SHIFT));   \
}

#define FL(XL, XR, KL, KR)                                          \
{                                                                   \
    (XR) = ((((XL) & (KL)) << 1) | (((XL) & (KL)) >> 31)) ^ (XR);   \
    (XL) = ((XR) | (KR)) ^ (XL);                                    \
}
    
#define FLInv(YL, YR, KL, KR)                                       \
{                                                                   \
    (YL) = ((YR) | (KR)) ^ (YL);                                    \
    (YR) = ((((YL) & (KL)) << 1) | (((YL) & (KL)) >> 31)) ^ (YR);   \
}
    
#define SHIFT_AND_PLACE(INDEX, OFFSET)                      \
{                                                           \
    TK[0] = KC[(OFFSET) * 4 + 0];                           \
    TK[1] = KC[(OFFSET) * 4 + 1];                           \
    TK[2] = KC[(OFFSET) * 4 + 2];                           \
    TK[3] = KC[(OFFSET) * 4 + 3];                           \
                                                            \
    for ( i = 1; i <= 4; i++ )                              \
        if (shifts[(INDEX)][(OFFSET)][i -1])                \
            ROTL(TK + i * 4, TK, (15 * i) % 32);            \
                                                            \
    for ( i = 0; i < 20; i++ )                              \
        if (indexes[(INDEX)][(OFFSET)][i] != -1) {          \
        RK[indexes[(INDEX)][(OFFSET)][i]] = TK[ i ];        \
    }                                                       \
}

static void camellia_feistel(const uint32_t x[2], const uint32_t k[2], uint32_t z[2])
{
    uint32_t I0, I1;
    I0 = x[0] ^ k[0];
    I1 = x[1] ^ k[1];

    I0 = (SBOX1((I0 >> 24) & 0xFF) << 24) |
         (SBOX2((I0 >> 16) & 0xFF) << 16) |
         (SBOX3((I0 >>  8) & 0xFF) <<  8) |
         (SBOX4((I0      ) & 0xFF)      );
    I1 = (SBOX2((I1 >> 24) & 0xFF) << 24) |
         (SBOX3((I1 >> 16) & 0xFF) << 16) |
         (SBOX4((I1 >>  8) & 0xFF) <<  8) |
         (SBOX1((I1      ) & 0xFF)      );

    I0 ^= (I1 << 8) | (I1 >> 24);
    I1 ^= (I0 << 16) | (I0 >> 16);
    I0 ^= (I1 >> 8) | (I1 << 24);
    I1 ^= (I0 >> 8) | (I0 << 24);

    z[0] ^= I1;
    z[1] ^= I0;
}

/*
 * Camellia key schedule (encryption)
 */
int camellia_setkey_enc( camellia_context *ctx, const unsigned char *key, unsigned int keysize )
{
    int idx;
    size_t i;
    uint32_t *RK;
    unsigned char t[64];
    uint32_t SIGMA[6][2];
    uint32_t KC[16];
    uint32_t TK[20];

    RK = ctx->rk;

    memset(t, 0, 64);
    memset(RK, 0, sizeof(ctx->rk));

    switch( keysize )
    {
        case 128: ctx->nr = 3; idx = 0; break;
        case 192:
        case 256: ctx->nr = 4; idx = 1; break;
        default : return( POLARSSL_ERR_CAMELLIA_INVALID_KEY_LENGTH );
    }

    for( i = 0; i < keysize / 8; ++i)
        t[i] = key[i];

    if (keysize == 192) {
        for (i = 0; i < 8; i++)
            t[24 + i] = ~t[16 + i];
    }

    /*
     * Prepare SIGMA values
     */
    for (i = 0; i < 6; i++) {
        GET_ULONG_BE(SIGMA[i][0], SIGMA_CHARS[i], 0);
        GET_ULONG_BE(SIGMA[i][1], SIGMA_CHARS[i], 4);
    }

    /*
     * Key storage in KC
     * Order: KL, KR, KA, KB
     */
    memset(KC, 0, sizeof(KC));

    /* Store KL, KR */
    for (i = 0; i < 8; i++)
        GET_ULONG_BE(KC[i], t, i * 4);

    /* Generate KA */
    for( i = 0; i < 4; ++i)
        KC[8 + i] = KC[i] ^ KC[4 + i];

    camellia_feistel(KC + 8, SIGMA[0], KC + 10);
    camellia_feistel(KC + 10, SIGMA[1], KC + 8);

    for( i = 0; i < 4; ++i)
        KC[8 + i] ^= KC[i];

    camellia_feistel(KC + 8, SIGMA[2], KC + 10);
    camellia_feistel(KC + 10, SIGMA[3], KC + 8);

    if (keysize > 128) {
        /* Generate KB */
        for( i = 0; i < 4; ++i)
            KC[12 + i] = KC[4 + i] ^ KC[8 + i];

        camellia_feistel(KC + 12, SIGMA[4], KC + 14);
        camellia_feistel(KC + 14, SIGMA[5], KC + 12);
    }

    /*
     * Generating subkeys
     */ 

    /* Manipulating KL */
    SHIFT_AND_PLACE(idx, 0);

    /* Manipulating KR */
    if (keysize > 128) {
        SHIFT_AND_PLACE(idx, 1);
    }

    /* Manipulating KA */
    SHIFT_AND_PLACE(idx, 2);

    /* Manipulating KB */
    if (keysize > 128) {
        SHIFT_AND_PLACE(idx, 3);
    }

    /* Do transpositions */
    for ( i = 0; i < 20; i++ ) {
        if (transposes[idx][i] != -1) {
            RK[32 + 12 * idx + i] = RK[transposes[idx][i]];
        }
    }

    return( 0 );
}

/*
 * Camellia key schedule (decryption)
 */
int camellia_setkey_dec( camellia_context *ctx, const unsigned char *key, unsigned int keysize )
{
    int idx;
    size_t i;
    camellia_context cty;
    uint32_t *RK;
    uint32_t *SK;
    int ret;

    switch( keysize )
    {
        case 128: ctx->nr = 3; idx = 0; break;
        case 192:
        case 256: ctx->nr = 4; idx = 1; break;
        default : return( POLARSSL_ERR_CAMELLIA_INVALID_KEY_LENGTH );
    }

    RK = ctx->rk;

    ret = camellia_setkey_enc(&cty, key, keysize);
    if( ret != 0 )
        return( ret );

    SK = cty.rk + 24 * 2 + 8 * idx * 2;

    *RK++ = *SK++;
    *RK++ = *SK++;
    *RK++ = *SK++;
    *RK++ = *SK++;

    for (i = 22 + 8 * idx, SK -= 6; i > 0; i--, SK -= 4)
    {
        *RK++ = *SK++;
        *RK++ = *SK++;
    }

    SK -= 2;

    *RK++ = *SK++;
    *RK++ = *SK++;
    *RK++ = *SK++;
    *RK++ = *SK++;

    memset( &cty, 0, sizeof( camellia_context ) );

    return( 0 );
}

/*
 * Camellia-ECB block encryption/decryption
 */
int camellia_crypt_ecb( camellia_context *ctx,
                    int mode,
                    const unsigned char input[16],
                    unsigned char output[16] )
{
    int NR;
    uint32_t *RK, X[4];

    ( (void) mode );

    NR = ctx->nr;
    RK = ctx->rk;

    GET_ULONG_BE( X[0], input,  0 );
    GET_ULONG_BE( X[1], input,  4 );
    GET_ULONG_BE( X[2], input,  8 );
    GET_ULONG_BE( X[3], input, 12 );

    X[0] ^= *RK++;
    X[1] ^= *RK++;
    X[2] ^= *RK++;
    X[3] ^= *RK++;

    while (NR) {
        --NR;
        camellia_feistel(X, RK, X + 2);
        RK += 2;
        camellia_feistel(X + 2, RK, X);
        RK += 2;
        camellia_feistel(X, RK, X + 2);
        RK += 2;
        camellia_feistel(X + 2, RK, X);
        RK += 2;
        camellia_feistel(X, RK, X + 2);
        RK += 2;
        camellia_feistel(X + 2, RK, X);
        RK += 2;

        if (NR) {
            FL(X[0], X[1], RK[0], RK[1]);
            RK += 2;
            FLInv(X[2], X[3], RK[0], RK[1]);
            RK += 2;
        }
    }

    X[2] ^= *RK++;
    X[3] ^= *RK++;
    X[0] ^= *RK++;
    X[1] ^= *RK++;

    PUT_ULONG_BE( X[2], output,  0 );
    PUT_ULONG_BE( X[3], output,  4 );
    PUT_ULONG_BE( X[0], output,  8 );
    PUT_ULONG_BE( X[1], output, 12 );

    return( 0 );
}

/*
 * Camellia-CBC buffer encryption/decryption
 */
int camellia_crypt_cbc( camellia_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( POLARSSL_ERR_CAMELLIA_INVALID_INPUT_LENGTH );

    if( mode == CAMELLIA_DECRYPT )
    {
        while( length > 0 )
        {
            memcpy( temp, input, 16 );
            camellia_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] );

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

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

    return( 0 );
}

#if defined(POLARSSL_CIPHER_MODE_CFB)
/*
 * Camellia-CFB128 buffer encryption/decryption
 */
int camellia_crypt_cfb128( camellia_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 == CAMELLIA_DECRYPT )
    {
        while( length-- )
        {
            if( n == 0 )
                camellia_crypt_ecb( ctx, CAMELLIA_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 )
                camellia_crypt_ecb( ctx, CAMELLIA_ENCRYPT, iv, iv );

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

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

    *iv_off = n;

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

#if defined(POLARSSL_CIPHER_MODE_CTR)
/*
 * Camellia-CTR buffer encryption/decryption
 */
int camellia_crypt_ctr( camellia_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, cb;
    size_t n = *nc_off;

    while( length-- )
    {
        if( n == 0 ) {
            camellia_crypt_ecb( ctx, CAMELLIA_ENCRYPT, nonce_counter, stream_block );

            i = 15;
            do {
               nonce_counter[i]++;
               cb = nonce_counter[i] == 0;
            } while( i-- && cb );

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

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

    *nc_off = n;

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

#if defined(POLARSSL_SELF_TEST)

#include <stdio.h>

/*
 * Camellia test vectors from:
 *
 * http://info.isl.ntt.co.jp/crypt/eng/camellia/technology.html:
 *   http://info.isl.ntt.co.jp/crypt/eng/camellia/dl/cryptrec/intermediate.txt
 *   http://info.isl.ntt.co.jp/crypt/eng/camellia/dl/cryptrec/t_camellia.txt
 *                      (For each bitlength: Key 0, Nr 39)
 */
#define CAMELLIA_TESTS_ECB  2

static const unsigned char camellia_test_ecb_key[3][CAMELLIA_TESTS_ECB][32] =
{
    {
        { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef,
          0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10 },
        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
    },
    {
        { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef,
          0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10,
          0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77 },
        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
    },
    {
        { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef,
          0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10,
          0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
          0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff },
        { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
    },
};

static const unsigned char camellia_test_ecb_plain[CAMELLIA_TESTS_ECB][16] =
{
    { 0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef,
      0xfe, 0xdc, 0xba, 0x98, 0x76, 0x54, 0x32, 0x10 },
    { 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00, 
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }
};

static const unsigned char camellia_test_ecb_cipher[3][CAMELLIA_TESTS_ECB][16] =
{
    {
        { 0x67, 0x67, 0x31, 0x38, 0x54, 0x96, 0x69, 0x73,
          0x08, 0x57, 0x06, 0x56, 0x48, 0xea, 0xbe, 0x43 },
        { 0x38, 0x3C, 0x6C, 0x2A, 0xAB, 0xEF, 0x7F, 0xDE,
          0x25, 0xCD, 0x47, 0x0B, 0xF7, 0x74, 0xA3, 0x31 }
    },
    {
        { 0xb4, 0x99, 0x34, 0x01, 0xb3, 0xe9, 0x96, 0xf8,
          0x4e, 0xe5, 0xce, 0xe7, 0xd7, 0x9b, 0x09, 0xb9 },
        { 0xD1, 0x76, 0x3F, 0xC0, 0x19, 0xD7, 0x7C, 0xC9,
          0x30, 0xBF, 0xF2, 0xA5, 0x6F, 0x7C, 0x93, 0x64 }
    },
    {
        { 0x9a, 0xcc, 0x23, 0x7d, 0xff, 0x16, 0xd7, 0x6c,
          0x20, 0xef, 0x7c, 0x91, 0x9e, 0x3a, 0x75, 0x09 },
        { 0x05, 0x03, 0xFB, 0x10, 0xAB, 0x24, 0x1E, 0x7C,
          0xF4, 0x5D, 0x8C, 0xDE, 0xEE, 0x47, 0x43, 0x35 }
    }
};

#define CAMELLIA_TESTS_CBC  3

static const unsigned char camellia_test_cbc_key[3][32] =
{
        { 0x2B, 0x7E, 0x15, 0x16, 0x28, 0xAE, 0xD2, 0xA6,
          0xAB, 0xF7, 0x15, 0x88, 0x09, 0xCF, 0x4F, 0x3C }
    ,
        { 0x8E, 0x73, 0xB0, 0xF7, 0xDA, 0x0E, 0x64, 0x52,
          0xC8, 0x10, 0xF3, 0x2B, 0x80, 0x90, 0x79, 0xE5,
          0x62, 0xF8, 0xEA, 0xD2, 0x52, 0x2C, 0x6B, 0x7B }
    ,
        { 0x60, 0x3D, 0xEB, 0x10, 0x15, 0xCA, 0x71, 0xBE,
          0x2B, 0x73, 0xAE, 0xF0, 0x85, 0x7D, 0x77, 0x81,
          0x1F, 0x35, 0x2C, 0x07, 0x3B, 0x61, 0x08, 0xD7,
          0x2D, 0x98, 0x10, 0xA3, 0x09, 0x14, 0xDF, 0xF4 }
};

static const unsigned char camellia_test_cbc_iv[16] =

    { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
      0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F }
;

static const unsigned char camellia_test_cbc_plain[CAMELLIA_TESTS_CBC][16] =
{
    { 0x6B, 0xC1, 0xBE, 0xE2, 0x2E, 0x40, 0x9F, 0x96,
      0xE9, 0x3D, 0x7E, 0x11, 0x73, 0x93, 0x17, 0x2A },
    { 0xAE, 0x2D, 0x8A, 0x57, 0x1E, 0x03, 0xAC, 0x9C,
      0x9E, 0xB7, 0x6F, 0xAC, 0x45, 0xAF, 0x8E, 0x51 },
    { 0x30, 0xC8, 0x1C, 0x46, 0xA3, 0x5C, 0xE4, 0x11,
      0xE5, 0xFB, 0xC1, 0x19, 0x1A, 0x0A, 0x52, 0xEF }

};

static const unsigned char camellia_test_cbc_cipher[3][CAMELLIA_TESTS_CBC][16] =
{
    {
        { 0x16, 0x07, 0xCF, 0x49, 0x4B, 0x36, 0xBB, 0xF0,
          0x0D, 0xAE, 0xB0, 0xB5, 0x03, 0xC8, 0x31, 0xAB },
        { 0xA2, 0xF2, 0xCF, 0x67, 0x16, 0x29, 0xEF, 0x78,
          0x40, 0xC5, 0xA5, 0xDF, 0xB5, 0x07, 0x48, 0x87 },
        { 0x0F, 0x06, 0x16, 0x50, 0x08, 0xCF, 0x8B, 0x8B,
          0x5A, 0x63, 0x58, 0x63, 0x62, 0x54, 0x3E, 0x54 }
    },
    {
        { 0x2A, 0x48, 0x30, 0xAB, 0x5A, 0xC4, 0xA1, 0xA2,
          0x40, 0x59, 0x55, 0xFD, 0x21, 0x95, 0xCF, 0x93 },
        { 0x5D, 0x5A, 0x86, 0x9B, 0xD1, 0x4C, 0xE5, 0x42,
          0x64, 0xF8, 0x92, 0xA6, 0xDD, 0x2E, 0xC3, 0xD5 },
        { 0x37, 0xD3, 0x59, 0xC3, 0x34, 0x98, 0x36, 0xD8,
          0x84, 0xE3, 0x10, 0xAD, 0xDF, 0x68, 0xC4, 0x49 }
    },
    {
        { 0xE6, 0xCF, 0xA3, 0x5F, 0xC0, 0x2B, 0x13, 0x4A,
          0x4D, 0x2C, 0x0B, 0x67, 0x37, 0xAC, 0x3E, 0xDA },
        { 0x36, 0xCB, 0xEB, 0x73, 0xBD, 0x50, 0x4B, 0x40,
          0x70, 0xB1, 0xB7, 0xDE, 0x2B, 0x21, 0xEB, 0x50 },
        { 0xE3, 0x1A, 0x60, 0x55, 0x29, 0x7D, 0x96, 0xCA,
          0x33, 0x30, 0xCD, 0xF1, 0xB1, 0x86, 0x0A, 0x83 }
    }
};

#if defined(POLARSSL_CIPHER_MODE_CTR)
/*
 * Camellia-CTR test vectors from:
 *
 * http://www.faqs.org/rfcs/rfc5528.html
 */

static const unsigned char camellia_test_ctr_key[3][16] =
{
    { 0xAE, 0x68, 0x52, 0xF8, 0x12, 0x10, 0x67, 0xCC,
      0x4B, 0xF7, 0xA5, 0x76, 0x55, 0x77, 0xF3, 0x9E },
    { 0x7E, 0x24, 0x06, 0x78, 0x17, 0xFA, 0xE0, 0xD7,
      0x43, 0xD6, 0xCE, 0x1F, 0x32, 0x53, 0x91, 0x63 },
    { 0x76, 0x91, 0xBE, 0x03, 0x5E, 0x50, 0x20, 0xA8,
      0xAC, 0x6E, 0x61, 0x85, 0x29, 0xF9, 0xA0, 0xDC }
};

static const unsigned char camellia_test_ctr_nonce_counter[3][16] =
{
    { 0x00, 0x00, 0x00, 0x30, 0x00, 0x00, 0x00, 0x00,
      0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01 },
    { 0x00, 0x6C, 0xB6, 0xDB, 0xC0, 0x54, 0x3B, 0x59,
      0xDA, 0x48, 0xD9, 0x0B, 0x00, 0x00, 0x00, 0x01 },
    { 0x00, 0xE0, 0x01, 0x7B, 0x27, 0x77, 0x7F, 0x3F,
      0x4A, 0x17, 0x86, 0xF0, 0x00, 0x00, 0x00, 0x01 }
};

static const unsigned char camellia_test_ctr_pt[3][48] =
{
    { 0x53, 0x69, 0x6E, 0x67, 0x6C, 0x65, 0x20, 0x62,
      0x6C, 0x6F, 0x63, 0x6B, 0x20, 0x6D, 0x73, 0x67 },

    { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
      0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
      0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
      0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F },

    { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
      0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
      0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
      0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F,
      0x20, 0x21, 0x22, 0x23 }
};

static const unsigned char camellia_test_ctr_ct[3][48] =
{
    { 0xD0, 0x9D, 0xC2, 0x9A, 0x82, 0x14, 0x61, 0x9A,
      0x20, 0x87, 0x7C, 0x76, 0xDB, 0x1F, 0x0B, 0x3F },
    { 0xDB, 0xF3, 0xC7, 0x8D, 0xC0, 0x83, 0x96, 0xD4,
      0xDA, 0x7C, 0x90, 0x77, 0x65, 0xBB, 0xCB, 0x44,
      0x2B, 0x8E, 0x8E, 0x0F, 0x31, 0xF0, 0xDC, 0xA7,
      0x2C, 0x74, 0x17, 0xE3, 0x53, 0x60, 0xE0, 0x48 },
    { 0xB1, 0x9D, 0x1F, 0xCD, 0xCB, 0x75, 0xEB, 0x88,
      0x2F, 0x84, 0x9C, 0xE2, 0x4D, 0x85, 0xCF, 0x73,
      0x9C, 0xE6, 0x4B, 0x2B, 0x5C, 0x9D, 0x73, 0xF1,
      0x4F, 0x2D, 0x5D, 0x9D, 0xCE, 0x98, 0x89, 0xCD,
      0xDF, 0x50, 0x86, 0x96 }
};

static const int camellia_test_ctr_len[3] =
    { 16, 32, 36 };
#endif /* POLARSSL_CIPHER_MODE_CTR */

/*
 * Checkup routine
 */
int camellia_self_test( int verbose )
{
    int i, j, u, v;
    unsigned char key[32];
    unsigned char buf[64];
    unsigned char src[16];
    unsigned char dst[16];
    unsigned char iv[16];
#if defined(POLARSSL_CIPHER_MODE_CTR)
    size_t offset, len;
    unsigned char nonce_counter[16];
    unsigned char stream_block[16];
#endif

    camellia_context ctx;

    memset( key, 0, 32 );

    for (j = 0; j < 6; j++) {
        u = j >> 1;
    v = j & 1;

    if( verbose != 0 )
        printf( "  CAMELLIA-ECB-%3d (%s): ", 128 + u * 64,
                (v == CAMELLIA_DECRYPT) ? "dec" : "enc");

    for (i = 0; i < CAMELLIA_TESTS_ECB; i++ ) {
        memcpy( key, camellia_test_ecb_key[u][i], 16 + 8 * u);

        if (v == CAMELLIA_DECRYPT) {
            camellia_setkey_dec(&ctx, key, 128 + u * 64);
            memcpy(src, camellia_test_ecb_cipher[u][i], 16);
            memcpy(dst, camellia_test_ecb_plain[i], 16);
        } else { /* CAMELLIA_ENCRYPT */
            camellia_setkey_enc(&ctx, key, 128 + u * 64);
            memcpy(src, camellia_test_ecb_plain[i], 16);
            memcpy(dst, camellia_test_ecb_cipher[u][i], 16);
        }

        camellia_crypt_ecb(&ctx, v, src, buf);

        if( memcmp( buf, dst, 16 ) != 0 )
        {
            if( verbose != 0 )
                printf( "failed\n" );

            return( 1 );
        }
    }

    if( verbose != 0 )
        printf( "passed\n" );
    }

    if( verbose != 0 )
        printf( "\n" );

    /*
     * CBC mode
     */
    for( j = 0; j < 6; j++ )
    {
        u = j >> 1;
        v = j  & 1;

        if( verbose != 0 )
            printf( "  CAMELLIA-CBC-%3d (%s): ", 128 + u * 64,
                    ( v == CAMELLIA_DECRYPT ) ? "dec" : "enc" );

    memcpy( src, camellia_test_cbc_iv, 16);
    memcpy( dst, camellia_test_cbc_iv, 16);
    memcpy( key, camellia_test_cbc_key[u], 16 + 8 * u);

    if (v == CAMELLIA_DECRYPT) {
        camellia_setkey_dec(&ctx, key, 128 + u * 64);
    } else {
        camellia_setkey_enc(&ctx, key, 128 + u * 64);
    }

    for (i = 0; i < CAMELLIA_TESTS_CBC; i++ ) {

        if (v == CAMELLIA_DECRYPT) {
            memcpy( iv , src, 16 );
            memcpy(src, camellia_test_cbc_cipher[u][i], 16);
            memcpy(dst, camellia_test_cbc_plain[i], 16);
        } else { /* CAMELLIA_ENCRYPT */
            memcpy( iv , dst, 16 );
            memcpy(src, camellia_test_cbc_plain[i], 16);
            memcpy(dst, camellia_test_cbc_cipher[u][i], 16);
        }

        camellia_crypt_cbc(&ctx, v, 16, iv, src, buf);

        if( memcmp( buf, dst, 16 ) != 0 )
        {
            if( verbose != 0 )
                printf( "failed\n" );

            return( 1 );
        }
    }

        if( verbose != 0 )
            printf( "passed\n" );
    }

    if( verbose != 0 )
        printf( "\n" );

#if defined(POLARSSL_CIPHER_MODE_CTR)
    /*
     * CTR mode
     */
    for( i = 0; i < 6; i++ )
    {
        u = i >> 1;
        v = i  & 1;

        if( verbose != 0 )
            printf( "  CAMELLIA-CTR-128 (%s): ",
                    ( v == CAMELLIA_DECRYPT ) ? "dec" : "enc" );

        memcpy( nonce_counter, camellia_test_ctr_nonce_counter[u], 16 );
        memcpy( key, camellia_test_ctr_key[u], 16 );

        offset = 0;
        camellia_setkey_enc( &ctx, key, 128 );

        if( v == CAMELLIA_DECRYPT )
        {
            len = camellia_test_ctr_len[u];
            memcpy( buf, camellia_test_ctr_ct[u], len );

            camellia_crypt_ctr( &ctx, len, &offset, nonce_counter, stream_block, buf, buf );

            if( memcmp( buf, camellia_test_ctr_pt[u], len ) != 0 )
            {
                if( verbose != 0 )
                    printf( "failed\n" );

                return( 1 );
            }
        }
        else
        {
            len = camellia_test_ctr_len[u];
            memcpy( buf, camellia_test_ctr_pt[u], len );

            camellia_crypt_ctr( &ctx, len, &offset, nonce_counter, stream_block, buf, buf );

            if( memcmp( buf, camellia_test_ctr_ct[u], len ) != 0 )
            {
                if( verbose != 0 )
                    printf( "failed\n" );

                return( 1 );
            }
        }

        if( verbose != 0 )
            printf( "passed\n" );
    }

    if( verbose != 0 )
        printf( "\n" );
#endif /* POLARSSL_CIPHER_MODE_CTR */

    return ( 0 );
}

#endif

#endif