/*

 * 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 <stdio.h>

#include <openssl/rc5.h>

#include "rc5_locl.h"

void RC5_32_cbc_encrypt(const unsigned char *in, unsigned char *out,

                        long length, RC5_32_KEY *ks, unsigned char *iv,

                        int encrypt)

{

    register unsigned long tin0, tin1;

    register unsigned long tout0, tout1, xor0, xor1;

    register long l = length;

    unsigned long tin[2];

    if (encrypt) {

        c2l(iv, tout0);

        c2l(iv, tout1);

        iv -= 8;

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

            c2l(in, tin0);

            c2l(in, tin1);

            tin0 ^= tout0;

            tin1 ^= tout1;

            tin[0] = tin0;

            tin[1] = tin1;

            RC5_32_encrypt(tin, ks);

            tout0 = tin[0];

            l2c(tout0, out);

            tout1 = tin[1];

            l2c(tout1, out);

        }

        if (l != -8) {

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

            tin0 ^= tout0;

            tin1 ^= tout1;

            tin[0] = tin0;

            tin[1] = tin1;

            RC5_32_encrypt(tin, ks);

            tout0 = tin[0];

            l2c(tout0, out);

            tout1 = tin[1];

            l2c(tout1, out);

        }

        l2c(tout0, iv);

        l2c(tout1, iv);

    } else {

        c2l(iv, xor0);

        c2l(iv, xor1);

        iv -= 8;

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

            c2l(in, tin0);

            tin[0] = tin0;

            c2l(in, tin1);

            tin[1] = tin1;

            RC5_32_decrypt(tin, ks);

            tout0 = tin[0] ^ xor0;

            tout1 = tin[1] ^ xor1;

            l2c(tout0, out);

            l2c(tout1, out);

            xor0 = tin0;

            xor1 = tin1;

        }

        if (l != -8) {

            c2l(in, tin0);

            tin[0] = tin0;

            c2l(in, tin1);

            tin[1] = tin1;

            RC5_32_decrypt(tin, ks);

            tout0 = tin[0] ^ xor0;

            tout1 = tin[1] ^ xor1;

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

            xor0 = tin0;

            xor1 = tin1;

        }

        l2c(xor0, iv);

        l2c(xor1, iv);

    }

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

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

}

void RC5_32_encrypt(unsigned long *d, RC5_32_KEY *key)

{

    RC5_32_INT a, b, *s;

    s = key->data;

    a = d[0] + s[0];

    b = d[1] + s[1];

    E_RC5_32(a, b, s, 2);

    E_RC5_32(a, b, s, 4);

    E_RC5_32(a, b, s, 6);

    E_RC5_32(a, b, s, 8);

    E_RC5_32(a, b, s, 10);

    E_RC5_32(a, b, s, 12);

    E_RC5_32(a, b, s, 14);

    E_RC5_32(a, b, s, 16);

    if (key->rounds == 12) {

        E_RC5_32(a, b, s, 18);

        E_RC5_32(a, b, s, 20);

        E_RC5_32(a, b, s, 22);

        E_RC5_32(a, b, s, 24);

    } else if (key->rounds == 16) {

        /* Do a full expansion to avoid a jump */

        E_RC5_32(a, b, s, 18);

        E_RC5_32(a, b, s, 20);

        E_RC5_32(a, b, s, 22);

        E_RC5_32(a, b, s, 24);

        E_RC5_32(a, b, s, 26);

        E_RC5_32(a, b, s, 28);

        E_RC5_32(a, b, s, 30);

        E_RC5_32(a, b, s, 32);

    }

    d[0] = a;

    d[1] = b;

}

void RC5_32_decrypt(unsigned long *d, RC5_32_KEY *key)

{

    RC5_32_INT a, b, *s;

    s = key->data;

    a = d[0];

    b = d[1];

    if (key->rounds == 16) {

        D_RC5_32(a, b, s, 32);

        D_RC5_32(a, b, s, 30);

        D_RC5_32(a, b, s, 28);

        D_RC5_32(a, b, s, 26);

        /* Do a full expansion to avoid a jump */

        D_RC5_32(a, b, s, 24);

        D_RC5_32(a, b, s, 22);

        D_RC5_32(a, b, s, 20);

        D_RC5_32(a, b, s, 18);

    } else if (key->rounds == 12) {

        D_RC5_32(a, b, s, 24);

        D_RC5_32(a, b, s, 22);

        D_RC5_32(a, b, s, 20);

        D_RC5_32(a, b, s, 18);

    }

    D_RC5_32(a, b, s, 16);

    D_RC5_32(a, b, s, 14);

    D_RC5_32(a, b, s, 12);

    D_RC5_32(a, b, s, 10);

    D_RC5_32(a, b, s, 8);

    D_RC5_32(a, b, s, 6);

    D_RC5_32(a, b, s, 4);

    D_RC5_32(a, b, s, 2);

    d[0] = a - s[0];

    d[1] = b - s[1];

}