/*

 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include "des_locl.h"

/* RSA's DESX */

void DES_xcbc_encrypt(const unsigned char *in, unsigned char *out,

                      long length, DES_key_schedule *schedule,

                      DES_cblock *ivec, const_DES_cblock *inw,

                      const_DES_cblock *outw, int enc)

{

    register DES_LONG tin0, tin1;

    register DES_LONG tout0, tout1, xor0, xor1;

    register DES_LONG inW0, inW1, outW0, outW1;

    register const unsigned char *in2;

    register long l = length;

    DES_LONG tin[2];

    unsigned char *iv;

    in2 = &(*inw)[0];

    c2l(in2, inW0);

    c2l(in2, inW1);

    in2 = &(*outw)[0];

    c2l(in2, outW0);

    c2l(in2, outW1);

    iv = &(*ivec)[0];

    if (enc) {

        c2l(iv, tout0);

        c2l(iv, tout1);

        for (l -= 8; l >= 0; l -= 8) {

            c2l(in, tin0);

            c2l(in, tin1);

            tin0 ^= tout0 ^ inW0;

            tin[0] = tin0;

            tin1 ^= tout1 ^ inW1;

            tin[1] = tin1;

            DES_encrypt1(tin, schedule, DES_ENCRYPT);

            tout0 = tin[0] ^ outW0;

            l2c(tout0, out);

            tout1 = tin[1] ^ outW1;

            l2c(tout1, out);

        }

        if (l != -8) {

            c2ln(in, tin0, tin1, l + 8);

            tin0 ^= tout0 ^ inW0;

            tin[0] = tin0;

            tin1 ^= tout1 ^ inW1;

            tin[1] = tin1;

            DES_encrypt1(tin, schedule, DES_ENCRYPT);

            tout0 = tin[0] ^ outW0;

            l2c(tout0, out);

            tout1 = tin[1] ^ outW1;

            l2c(tout1, out);

        }

        iv = &(*ivec)[0];

        l2c(tout0, iv);

        l2c(tout1, iv);

    } else {

        c2l(iv, xor0);

        c2l(iv, xor1);

        for (l -= 8; l > 0; l -= 8) {

            c2l(in, tin0);

            tin[0] = tin0 ^ outW0;

            c2l(in, tin1);

            tin[1] = tin1 ^ outW1;

            DES_encrypt1(tin, schedule, DES_DECRYPT);

            tout0 = tin[0] ^ xor0 ^ inW0;

            tout1 = tin[1] ^ xor1 ^ inW1;

            l2c(tout0, out);

            l2c(tout1, out);

            xor0 = tin0;

            xor1 = tin1;

        }

        if (l != -8) {

            c2l(in, tin0);

            tin[0] = tin0 ^ outW0;

            c2l(in, tin1);

            tin[1] = tin1 ^ outW1;

            DES_encrypt1(tin, schedule, DES_DECRYPT);

            tout0 = tin[0] ^ xor0 ^ inW0;

            tout1 = tin[1] ^ xor1 ^ inW1;

            l2cn(tout0, tout1, out, l + 8);

            xor0 = tin0;

            xor1 = tin1;

        }

        iv = &(*ivec)[0];

        l2c(xor0, iv);

        l2c(xor1, iv);

    }

    tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;

    inW0 = inW1 = outW0 = outW1 = 0;

    tin[0] = tin[1] = 0;

}