74 lines
2.0 KiB
C
74 lines
2.0 KiB
C
|
/*
|
||
|
* 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 "des_local.h"
|
||
|
|
||
|
/*
|
||
|
* The input and output encrypted as though 64bit cfb mode is being used.
|
||
|
* The extra state information to record how much of the 64bit block we have
|
||
|
* used is contained in *num;
|
||
|
*/
|
||
|
|
||
|
void DES_cfb64_encrypt(const unsigned char *in, unsigned char *out,
|
||
|
long length, DES_key_schedule *schedule,
|
||
|
DES_cblock *ivec, int *num, int enc)
|
||
|
{
|
||
|
register DES_LONG v0, v1;
|
||
|
register long l = length;
|
||
|
register int n = *num;
|
||
|
DES_LONG ti[2];
|
||
|
unsigned char *iv, c, cc;
|
||
|
|
||
|
iv = &(*ivec)[0];
|
||
|
if (enc) {
|
||
|
while (l--) {
|
||
|
if (n == 0) {
|
||
|
c2l(iv, v0);
|
||
|
ti[0] = v0;
|
||
|
c2l(iv, v1);
|
||
|
ti[1] = v1;
|
||
|
DES_encrypt1(ti, schedule, DES_ENCRYPT);
|
||
|
iv = &(*ivec)[0];
|
||
|
v0 = ti[0];
|
||
|
l2c(v0, iv);
|
||
|
v0 = ti[1];
|
||
|
l2c(v0, iv);
|
||
|
iv = &(*ivec)[0];
|
||
|
}
|
||
|
c = *(in++) ^ iv[n];
|
||
|
*(out++) = c;
|
||
|
iv[n] = c;
|
||
|
n = (n + 1) & 0x07;
|
||
|
}
|
||
|
} else {
|
||
|
while (l--) {
|
||
|
if (n == 0) {
|
||
|
c2l(iv, v0);
|
||
|
ti[0] = v0;
|
||
|
c2l(iv, v1);
|
||
|
ti[1] = v1;
|
||
|
DES_encrypt1(ti, schedule, DES_ENCRYPT);
|
||
|
iv = &(*ivec)[0];
|
||
|
v0 = ti[0];
|
||
|
l2c(v0, iv);
|
||
|
v0 = ti[1];
|
||
|
l2c(v0, iv);
|
||
|
iv = &(*ivec)[0];
|
||
|
}
|
||
|
cc = *(in++);
|
||
|
c = iv[n];
|
||
|
iv[n] = cc;
|
||
|
*(out++) = c ^ cc;
|
||
|
n = (n + 1) & 0x07;
|
||
|
}
|
||
|
}
|
||
|
v0 = v1 = ti[0] = ti[1] = c = cc = 0;
|
||
|
*num = n;
|
||
|
}
|