yuzu/externals/libressl/crypto/rc4/rc4_skey.c
2020-12-28 15:15:37 +00:00

116 lines
4.2 KiB
C
Executable File

/* $OpenBSD: rc4_skey.c,v 1.14 2015/10/20 15:50:13 jsing Exp $ */
/* 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/rc4.h>
#include "rc4_locl.h"
#include <openssl/opensslv.h>
const char *
RC4_options(void)
{
#ifdef RC4_INDEX
if (sizeof(RC4_INT) == 1)
return("rc4(idx,char)");
else
return("rc4(idx,int)");
#else
if (sizeof(RC4_INT) == 1)
return("rc4(ptr,char)");
else
return("rc4(ptr,int)");
#endif
}
/* RC4 as implemented from a posting from
* Newsgroups: sci.crypt
* From: sterndark@netcom.com (David Sterndark)
* Subject: RC4 Algorithm revealed.
* Message-ID: <sternCvKL4B.Hyy@netcom.com>
* Date: Wed, 14 Sep 1994 06:35:31 GMT
*/
void
RC4_set_key(RC4_KEY *key, int len, const unsigned char *data)
{
RC4_INT tmp;
int id1, id2;
RC4_INT *d;
unsigned int i;
d = &(key->data[0]);
key->x = 0;
key->y = 0;
id1 = id2 = 0;
#define SK_LOOP(d,n) { \
tmp=d[(n)]; \
id2 = (data[id1] + tmp + id2) & 0xff; \
if (++id1 == len) id1=0; \
d[(n)]=d[id2]; \
d[id2]=tmp; }
for (i = 0; i < 256; i++)
d[i] = i;
for (i = 0; i < 256; i += 4) {
SK_LOOP(d, i + 0);
SK_LOOP(d, i + 1);
SK_LOOP(d, i + 2);
SK_LOOP(d, i + 3);
}
}