mirror of
https://github.com/openssl/openssl.git
synced 2024-12-27 06:21:43 +08:00
33388b44b6
Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/11616)
89 lines
2.5 KiB
C
89 lines
2.5 KiB
C
/*
|
|
* Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
|
|
*
|
|
* Licensed under the Apache License 2.0 (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
|
|
*/
|
|
|
|
/*
|
|
* DES low level APIs are deprecated for public use, but still ok for internal
|
|
* use.
|
|
*/
|
|
#include "internal/deprecated.h"
|
|
|
|
#include "des_local.h"
|
|
|
|
/*
|
|
* The input and output are loaded in multiples of 8 bits. What this means is
|
|
* that if you have numbits=12 and length=2 the first 12 bits will be
|
|
* retrieved from the first byte and half the second. The second 12 bits
|
|
* will come from the 3rd and half the 4th byte.
|
|
*/
|
|
void DES_ofb_encrypt(const unsigned char *in, unsigned char *out, int numbits,
|
|
long length, DES_key_schedule *schedule,
|
|
DES_cblock *ivec)
|
|
{
|
|
register DES_LONG d0, d1, vv0, vv1, v0, v1, n = (numbits + 7) / 8;
|
|
register DES_LONG mask0, mask1;
|
|
register long l = length;
|
|
register int num = numbits;
|
|
DES_LONG ti[2];
|
|
unsigned char *iv;
|
|
|
|
if (num > 64)
|
|
return;
|
|
if (num > 32) {
|
|
mask0 = 0xffffffffL;
|
|
if (num >= 64)
|
|
mask1 = mask0;
|
|
else
|
|
mask1 = (1L << (num - 32)) - 1;
|
|
} else {
|
|
if (num == 32)
|
|
mask0 = 0xffffffffL;
|
|
else
|
|
mask0 = (1L << num) - 1;
|
|
mask1 = 0x00000000L;
|
|
}
|
|
|
|
iv = &(*ivec)[0];
|
|
c2l(iv, v0);
|
|
c2l(iv, v1);
|
|
ti[0] = v0;
|
|
ti[1] = v1;
|
|
while (l-- > 0) {
|
|
ti[0] = v0;
|
|
ti[1] = v1;
|
|
DES_encrypt1((DES_LONG *)ti, schedule, DES_ENCRYPT);
|
|
vv0 = ti[0];
|
|
vv1 = ti[1];
|
|
c2ln(in, d0, d1, n);
|
|
in += n;
|
|
d0 = (d0 ^ vv0) & mask0;
|
|
d1 = (d1 ^ vv1) & mask1;
|
|
l2cn(d0, d1, out, n);
|
|
out += n;
|
|
|
|
if (num == 32) {
|
|
v0 = v1;
|
|
v1 = vv0;
|
|
} else if (num == 64) {
|
|
v0 = vv0;
|
|
v1 = vv1;
|
|
} else if (num > 32) { /* && num != 64 */
|
|
v0 = ((v1 >> (num - 32)) | (vv0 << (64 - num))) & 0xffffffffL;
|
|
v1 = ((vv0 >> (num - 32)) | (vv1 << (64 - num))) & 0xffffffffL;
|
|
} else { /* num < 32 */
|
|
|
|
v0 = ((v0 >> num) | (v1 << (32 - num))) & 0xffffffffL;
|
|
v1 = ((v1 >> num) | (vv0 << (32 - num))) & 0xffffffffL;
|
|
}
|
|
}
|
|
iv = &(*ivec)[0];
|
|
l2c(v0, iv);
|
|
l2c(v1, iv);
|
|
v0 = v1 = d0 = d1 = ti[0] = ti[1] = vv0 = vv1 = 0;
|
|
}
|