rc4.c

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/* crypto/rc4/rc4.c */
/* Copyright (C) 1995-1998 Eric Young ([email protected])
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young ([email protected]).
 * 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 ([email protected]).
 * 
 * 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 ([email protected])"
 *    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 ([email protected])"
 * 
 * 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>
#include <openssl/evp.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,"%s",*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 OPENSSL_SYS_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;
        }

    EVP_Digest((unsigned char *)keystr,strlen(keystr),md,NULL,EVP_md5(),NULL);
    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);
    }