/* crypto/cast/c_enc.c */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
#include <openssl/cast.h>
#include "cast_lcl.h"
void CAST_encrypt(CAST_LONG *data, const CAST_KEY *key)
{
register CAST_LONG l, r, t;
const register CAST_LONG *k;
k = &(key->data[0]);
l = data[0];
r = data[1];
E_CAST(0, k, l, r, +, ^, -);
E_CAST(1, k, r, l, ^, -, +);
E_CAST(2, k, l, r, -, +, ^);
E_CAST(3, k, r, l, +, ^, -);
E_CAST(4, k, l, r, ^, -, +);
E_CAST(5, k, r, l, -, +, ^);
E_CAST(6, k, l, r, +, ^, -);
E_CAST(7, k, r, l, ^, -, +);
E_CAST(8, k, l, r, -, +, ^);
E_CAST(9, k, r, l, +, ^, -);
E_CAST(10, k, l, r, ^, -, +);
E_CAST(11, k, r, l, -, +, ^);
if (!key->short_key) {
E_CAST(12, k, l, r, +, ^, -);
E_CAST(13, k, r, l, ^, -, +);
E_CAST(14, k, l, r, -, +, ^);
E_CAST(15, k, r, l, +, ^, -);
}
data[1] = l & 0xffffffffL;
data[0] = r & 0xffffffffL;
}
void CAST_decrypt(CAST_LONG *data, const CAST_KEY *key)
{
register CAST_LONG l, r, t;
const register CAST_LONG *k;
k = &(key->data[0]);
l = data[0];
r = data[1];
if (!key->short_key) {
E_CAST(15, k, l, r, +, ^, -);
E_CAST(14, k, r, l, -, +, ^);
E_CAST(13, k, l, r, ^, -, +);
E_CAST(12, k, r, l, +, ^, -);
}
E_CAST(11, k, l, r, -, +, ^);
E_CAST(10, k, r, l, ^, -, +);
E_CAST(9, k, l, r, +, ^, -);
E_CAST(8, k, r, l, -, +, ^);
E_CAST(7, k, l, r, ^, -, +);
E_CAST(6, k, r, l, +, ^, -);
E_CAST(5, k, l, r, -, +, ^);
E_CAST(4, k, r, l, ^, -, +);
E_CAST(3, k, l, r, +, ^, -);
E_CAST(2, k, r, l, -, +, ^);
E_CAST(1, k, l, r, ^, -, +);
E_CAST(0, k, r, l, +, ^, -);
data[1] = l & 0xffffffffL;
data[0] = r & 0xffffffffL;
}
void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out,
long length, const CAST_KEY *ks, unsigned char *iv,
int enc)
{
register CAST_LONG tin0, tin1;
register CAST_LONG tout0, tout1, xor0, xor1;
register long l = length;
CAST_LONG tin[2];
if (enc) {
n2l(iv, tout0);
n2l(iv, tout1);
iv -= 8;
for (l -= 8; l >= 0; l -= 8) {
n2l(in, tin0);
n2l(in, tin1);
tin0 ^= tout0;
tin1 ^= tout1;
tin[0] = tin0;
tin[1] = tin1;
CAST_encrypt(tin, ks);
tout0 = tin[0];
tout1 = tin[1];
l2n(tout0, out);
l2n(tout1, out);
}
if (l != -8) {
n2ln(in, tin0, tin1, l + 8);
tin0 ^= tout0;
tin1 ^= tout1;
tin[0] = tin0;
tin[1] = tin1;
CAST_encrypt(tin, ks);
tout0 = tin[0];
tout1 = tin[1];
l2n(tout0, out);
l2n(tout1, out);
}
l2n(tout0, iv);
l2n(tout1, iv);
} else {
n2l(iv, xor0);
n2l(iv, xor1);
iv -= 8;
for (l -= 8; l >= 0; l -= 8) {
n2l(in, tin0);
n2l(in, tin1);
tin[0] = tin0;
tin[1] = tin1;
CAST_decrypt(tin, ks);
tout0 = tin[0] ^ xor0;
tout1 = tin[1] ^ xor1;
l2n(tout0, out);
l2n(tout1, out);
xor0 = tin0;
xor1 = tin1;
}
if (l != -8) {
n2l(in, tin0);
n2l(in, tin1);
tin[0] = tin0;
tin[1] = tin1;
CAST_decrypt(tin, ks);
tout0 = tin[0] ^ xor0;
tout1 = tin[1] ^ xor1;
l2nn(tout0, tout1, out, l + 8);
xor0 = tin0;
xor1 = tin1;
}
l2n(xor0, iv);
l2n(xor1, iv);
}
tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
tin[0] = tin[1] = 0;
}
