86 lines
2.2 KiB
C
86 lines
2.2 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 <openssl/rc4.h>
|
||
|
|
#include "rc4_local.h"
|
||
|
|
|
||
|
|
/*-
|
||
|
|
* RC4 as implemented from a posting from
|
||
|
|
* Newsgroups: sci.crypt
|
||
|
|
* Subject: RC4 Algorithm revealed.
|
||
|
|
* Message-ID: <sternCvKL4B.Hyy@netcom.com>
|
||
|
|
* Date: Wed, 14 Sep 1994 06:35:31 GMT
|
||
|
|
*/
|
||
|
|
|
||
|
|
void RC4(RC4_KEY *key, size_t len, const unsigned char *indata,
|
||
|
|
unsigned char *outdata)
|
||
|
|
{
|
||
|
|
register RC4_INT *d;
|
||
|
|
register RC4_INT x, y, tx, ty;
|
||
|
|
size_t i;
|
||
|
|
|
||
|
|
x = key->x;
|
||
|
|
y = key->y;
|
||
|
|
d = key->data;
|
||
|
|
|
||
|
|
#define LOOP(in,out) \
|
||
|
|
x=((x+1)&0xff); \
|
||
|
|
tx=d[x]; \
|
||
|
|
y=(tx+y)&0xff; \
|
||
|
|
d[x]=ty=d[y]; \
|
||
|
|
d[y]=tx; \
|
||
|
|
(out) = d[(tx+ty)&0xff]^ (in);
|
||
|
|
|
||
|
|
i = len >> 3;
|
||
|
|
if (i) {
|
||
|
|
for (;;) {
|
||
|
|
LOOP(indata[0], outdata[0]);
|
||
|
|
LOOP(indata[1], outdata[1]);
|
||
|
|
LOOP(indata[2], outdata[2]);
|
||
|
|
LOOP(indata[3], outdata[3]);
|
||
|
|
LOOP(indata[4], outdata[4]);
|
||
|
|
LOOP(indata[5], outdata[5]);
|
||
|
|
LOOP(indata[6], outdata[6]);
|
||
|
|
LOOP(indata[7], outdata[7]);
|
||
|
|
indata += 8;
|
||
|
|
outdata += 8;
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
i = len & 0x07;
|
||
|
|
if (i) {
|
||
|
|
for (;;) {
|
||
|
|
LOOP(indata[0], outdata[0]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
LOOP(indata[1], outdata[1]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
LOOP(indata[2], outdata[2]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
LOOP(indata[3], outdata[3]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
LOOP(indata[4], outdata[4]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
LOOP(indata[5], outdata[5]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
LOOP(indata[6], outdata[6]);
|
||
|
|
if (--i == 0)
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
key->x = x;
|
||
|
|
key->y = y;
|
||
|
|
}
|