rc4_skey.c
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- /* crypto/rc4/rc4_skey.c */
- /* 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_version="RC4" OPENSSL_VERSION_PTEXT;
- 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)
- {
- 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; }
- #if defined(OPENSSL_CPUID_OBJ) && !defined(OPENSSL_NO_ASM)
- # if defined(__i386) || defined(__i386__) || defined(_M_IX86) ||
- defined(__INTEL__) ||
- defined(__x86_64) || defined(__x86_64__) || defined(_M_AMD64)
- if (sizeof(RC4_INT) > 1) {
- /*
- * Unlike all other x86 [and x86_64] implementations,
- * Intel P4 core [including EM64T] was found to perform
- * poorly with wider RC4_INT. Performance improvement
- * for IA-32 hand-coded assembler turned out to be 2.8x
- * if re-coded for RC4_CHAR! It's however inappropriate
- * to just switch to RC4_CHAR for x86[_64], as non-P4
- * implementations suffer from significant performance
- * losses then, e.g. PIII exhibits >2x deterioration,
- * and so does Opteron. In order to assure optimal
- * all-round performance, let us [try to] detect P4 at
- * run-time by checking upon HTT bit in CPU capability
- * vector and set up compressed key schedule, which is
- * recognized by correspondingly updated assembler
- * module...
- * <appro@fy.chalmers.se>
- */
- if (OPENSSL_ia32cap_P & (1<<28)) {
- unsigned char *cp=(unsigned char *)d;
- for (i=0;i<256;i++) cp[i]=i;
- for (i=0;i<256;i++) SK_LOOP(cp,i);
- /* mark schedule as compressed! */
- d[256/sizeof(RC4_INT)]=-1;
- return;
- }
- }
- # endif
- #endif
- 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);
- }
- }
-