96 lines
3.4 KiB
C
96 lines
3.4 KiB
C
/* ====================================================================
|
|
* Copyright (c) 2008 The OpenSSL Project. All rights reserved.
|
|
*
|
|
* 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 above 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 acknowledgment:
|
|
* "This product includes software developed by the OpenSSL Project
|
|
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
|
|
*
|
|
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
|
|
* endorse or promote products derived from this software without
|
|
* prior written permission. For written permission, please contact
|
|
* openssl-core@openssl.org.
|
|
*
|
|
* 5. Products derived from this software may not be called "OpenSSL"
|
|
* nor may "OpenSSL" appear in their names without prior written
|
|
* permission of the OpenSSL Project.
|
|
*
|
|
* 6. Redistributions of any form whatsoever must retain the following
|
|
* acknowledgment:
|
|
* "This product includes software developed by the OpenSSL Project
|
|
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
|
|
* EXPRESSED 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 OpenSSL PROJECT OR
|
|
* ITS 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.
|
|
* ==================================================================== */
|
|
|
|
#include <openssl/type_check.h>
|
|
|
|
#include <assert.h>
|
|
#include <string.h>
|
|
|
|
#include "internal.h"
|
|
|
|
|
|
OPENSSL_COMPILE_ASSERT((16 % sizeof(size_t)) == 0, bad_size_t_size_ofb);
|
|
|
|
void CRYPTO_ofb128_encrypt(const uint8_t *in, uint8_t *out, size_t len,
|
|
const void *key, uint8_t ivec[16], unsigned *num,
|
|
block128_f block) {
|
|
assert(in && out && key && ivec && num);
|
|
|
|
unsigned n = *num;
|
|
|
|
while (n && len) {
|
|
*(out++) = *(in++) ^ ivec[n];
|
|
--len;
|
|
n = (n + 1) % 16;
|
|
}
|
|
|
|
while (len >= 16) {
|
|
(*block)(ivec, ivec, key);
|
|
for (; n < 16; n += sizeof(size_t)) {
|
|
size_t a, b;
|
|
OPENSSL_memcpy(&a, in + n, sizeof(size_t));
|
|
OPENSSL_memcpy(&b, ivec + n, sizeof(size_t));
|
|
|
|
const size_t c = a ^ b;
|
|
OPENSSL_memcpy(out + n, &c, sizeof(size_t));
|
|
}
|
|
len -= 16;
|
|
out += 16;
|
|
in += 16;
|
|
n = 0;
|
|
}
|
|
if (len) {
|
|
(*block)(ivec, ivec, key);
|
|
while (len--) {
|
|
out[n] = in[n] ^ ivec[n];
|
|
++n;
|
|
}
|
|
}
|
|
*num = n;
|
|
}
|