/* * Copyright 1995-2016 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 */ #include #include "rc4_local.h" #include const char *RC4_options(void) { if (sizeof(RC4_INT) == 1) return "rc4(char)"; else return "rc4(int)"; } /*- * RC4 as implemented from a posting from * Newsgroups: sci.crypt * Subject: RC4 Algorithm revealed. * Message-ID: * Date: Wed, 14 Sep 1994 06:35:31 GMT */ void RC4_set_key(RC4_KEY *key, int len, const unsigned char *data) { register RC4_INT tmp; register int id1, id2; register 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); } }