/*

 * 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 <openssl/rc5.h>

#include "rc5_locl.h"

void RC5_32_set_key(RC5_32_KEY *key, int len, const unsigned char *data,

                    int rounds)

{

    RC5_32_INT L[64], l, ll, A, B, *S, k;

    int i, j, m, c, t, ii, jj;

    if ((rounds != RC5_16_ROUNDS) &&

        (rounds != RC5_12_ROUNDS) && (rounds != RC5_8_ROUNDS))

        rounds = RC5_16_ROUNDS;

    key->rounds = rounds;

    S = &(key->data[0]);

    j = 0;

    for (i = 0; i <= (len - 8); i += 8) {

        c2l(data, l);

        L[j++] = l;

        c2l(data, l);

        L[j++] = l;

    }

    ii = len - i;

    if (ii) {

        k = len & 0x07;

        c2ln(data, l, ll, k);

        L[j + 0] = l;

        L[j + 1] = ll;

    }

    c = (len + 3) / 4;

    t = (rounds + 1) * 2;

    S[0] = RC5_32_P;

    for (i = 1; i < t; i++)

        S[i] = (S[i - 1] + RC5_32_Q) & RC5_32_MASK;

    j = (t > c) ? t : c;

    j *= 3;

    ii = jj = 0;

    A = B = 0;

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

        k = (S[ii] + A + B) & RC5_32_MASK;

        A = S[ii] = ROTATE_l32(k, 3);

        m = (int)(A + B);

        k = (L[jj] + A + B) & RC5_32_MASK;

        B = L[jj] = ROTATE_l32(k, m);

        if (++ii >= t)

            ii = 0;

        if (++jj >= c)

            jj = 0;

    }

}