rc4.c

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/* crypto/rc4/rc4.c */
/* Copyright (C) 1995-1998 Eric Young ([e-mail])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([e-mail]).
 * 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 ([e-mail]).
 * 
 * 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 ([e-mail])"
 *    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 ([e-mail])"
 * 
 * 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "openssl/rc4.h"

char *usage[]={
"usage: rc4 args\n",
"\n",
" -in arg         - input file - default stdin\n",
" -out arg        - output file - default stdout\n",
" -key key        - password\n",
NULL
};

int main(int argc, char *argv[])
	{
	FILE *in=NULL,*out=NULL;
	char *infile=NULL,*outfile=NULL,*keystr=NULL;
	RC4_KEY key;
	char buf[BUFSIZ];
	int badops=0,i;
	char **pp;
	unsigned char md[MD5_DIGEST_LENGTH];

	argc--;
	argv++;
	while (argc >= 1)
		{
		if 	(strcmp(*argv,"-in") == 0)
			{
			if (--argc < 1) goto bad;
			infile= *(++argv);
			}
		else if (strcmp(*argv,"-out") == 0)
			{
			if (--argc < 1) goto bad;
			outfile= *(++argv);
			}
		else if (strcmp(*argv,"-key") == 0)
			{
			if (--argc < 1) goto bad;
			keystr= *(++argv);
			}
		else
			{
			fprintf(stderr,"unknown option %s\n",*argv);
			badops=1;
			break;
			}
		argc--;
		argv++;
		}

	if (badops)
		{
bad:
		for (pp=usage; (*pp != NULL); pp++)
			fprintf(stderr,*pp);
		exit(1);
		}

	if (infile == NULL)
		in=stdin;
	else
		{
		in=fopen(infile,"r");
		if (in == NULL)
			{
			perror("open");
			exit(1);
			}

		}
	if (outfile == NULL)
		out=stdout;
	else
		{
		out=fopen(outfile,"w");
		if (out == NULL)
			{
			perror("open");
			exit(1);
			}
		}
		
#ifdef MSDOS
	/* This should set the file to binary mode. */
	{
#include <fcntl.h>
	setmode(fileno(in),O_BINARY);
	setmode(fileno(out),O_BINARY);
	}
#endif

	if (keystr == NULL)
		{ /* get key */
		i=EVP_read_pw_string(buf,BUFSIZ,"Enter RC4 password:",0);
		if (i != 0)
			{
			OPENSSL_cleanse(buf,BUFSIZ);
			fprintf(stderr,"bad password read\n");
			exit(1);
			}
		keystr=buf;
		}

	MD5((unsigned char *)keystr,(unsigned long)strlen(keystr),md);
	OPENSSL_cleanse(keystr,strlen(keystr));
	RC4_set_key(&key,MD5_DIGEST_LENGTH,md);
	
	for(;;)
		{
		i=fread(buf,1,BUFSIZ,in);
		if (i == 0) break;
		if (i < 0)
			{
			perror("read");
			exit(1);
			}
		RC4(&key,(unsigned int)i,(unsigned char *)buf,
			(unsigned char *)buf);
		i=fwrite(buf,(unsigned int)i,1,out);
		if (i != 1)
			{
			perror("write");
			exit(1);
			}
		}
	fclose(out);
	fclose(in);
	exit(0);
	return(1);
	}