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Diffstat (limited to 'crypto/rc4/rc4_enc.c')
| -rw-r--r-- | crypto/rc4/rc4_enc.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/crypto/rc4/rc4_enc.c b/crypto/rc4/rc4_enc.c new file mode 100644 index 0000000..de57a97 --- /dev/null +++ b/crypto/rc4/rc4_enc.c @@ -0,0 +1,195 @@ +/* crypto/rc4/rc4_enc.org */ +/* Copyright (C) 1995-1997 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.] + */ + +/* WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING + * + * Always modify rc4_enc.org since rc4_enc.c is automatically generated from + * it during SSLeay configuration. + * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING + */ + +#include "rc4.h" + +/* if this is defined data[i] is used instead of *data, this is a %20 + * speedup on x86 */ +#undef RC4_INDEX + +char *RC4_version="RC4 part of SSLeay 0.8.1a 24-Jun-1998"; + +char *RC4_options() + { +#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(key, len, data) +RC4_KEY *key; +int len; +register unsigned char *data; + { + register RC4_INT tmp; + register int id1,id2; + register RC4_INT *d; + unsigned int i; + + d= &(key->data[0]); + for (i=0; i<256; i++) + d[i]=i; + key->x = 0; + key->y = 0; + id1=id2=0; + +#define SK_LOOP(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+=4) + { + SK_LOOP(i+0); + SK_LOOP(i+1); + SK_LOOP(i+2); + SK_LOOP(i+3); + } + } + +void RC4(key, len, indata, outdata) +RC4_KEY *key; +unsigned long len; +unsigned char *indata; +unsigned char *outdata; + { + register RC4_INT *d; + register RC4_INT x,y,tx,ty; + int 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); + +#ifndef RC4_INDEX +#define RC4_LOOP(a,b,i) LOOP(*((a)++),*((b)++)) +#else +#define RC4_LOOP(a,b,i) LOOP(a[i],b[i]) +#endif + + i= -(int)len; + i=(int)(len>>3L); + if (i) + { + for (;;) + { + RC4_LOOP(indata,outdata,0); + RC4_LOOP(indata,outdata,1); + RC4_LOOP(indata,outdata,2); + RC4_LOOP(indata,outdata,3); + RC4_LOOP(indata,outdata,4); + RC4_LOOP(indata,outdata,5); + RC4_LOOP(indata,outdata,6); + RC4_LOOP(indata,outdata,7); +#ifdef RC4_INDEX + indata+=8; + outdata+=8; +#endif + if (--i == 0) break; + } + } + i=(int)len&0x07; + if (i) + { + for (;;) + { + RC4_LOOP(indata,outdata,0); if (--i == 0) break; + RC4_LOOP(indata,outdata,1); if (--i == 0) break; + RC4_LOOP(indata,outdata,2); if (--i == 0) break; + RC4_LOOP(indata,outdata,3); if (--i == 0) break; + RC4_LOOP(indata,outdata,4); if (--i == 0) break; + RC4_LOOP(indata,outdata,5); if (--i == 0) break; + RC4_LOOP(indata,outdata,6); if (--i == 0) break; + } + } + key->x=x; + key->y=y; + } |