"makekey" for Linux

By Steggy
BCS Technology Limited
Email: steggy@bcstechnology.net
Web Site: http://www.bcstechnology.net

The need for makekey has to do with interfacing to a Throughbred Dictionary-IV app originally written to run on SCO OSR5. I now have complete portability for any other use of the app.

Apparently there was once a Linux makekey, but it was "deprecated" in favor of "crypt(3)".

Apparently there was also (and may still be somewhere) a command line "crypt" that I could have "front-ended" for my needs, but it doesn't exist on my system. As there really isn't much to this, I just went ahead and wrote what I needed.

Compile source with gcc -lcrypt -m32 -o makekey makekey.c. The -m32 option is required on a 64 bit system. Operation is the same as makekey found on SCO, BSD, AIX, etc.

/*
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* *                                                                         * *
* *                   makekey: Generate Encrypted Password                  * *
* *                                                                         * *
* * Copyright (C)1994-2009 by BCS Technology Limited.  All rights reserved. * *
* *                                                                         * *
* * Permission is granted to use, copy, modify and/or distribute this soft- * *
* * ware, provided proper attribution and credit is given and all copyright * *
* * notices remain intact.  This software is *NOT* in the public domain and * *
* * has *NOT* been GPLed.                                                   * *
* *                                                                         * *
* * DISCLAIMER:  BCS Technology Limited does not warrant that this software * *
* *              is suitable for any particular purpose,  or that  it  will * *
* *              even work as intended.  No technical support of  any  kind * *
* *              will be offered.  We take no responsibility  for  anything * *
* *              unpleasant that might happen to your system, your business * *
* *              or your financial well-being due to the use of this  soft- * *
* *              ware.  In other words, USE AT YOUR OWN RISK.               * *
* *                                                                         * *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*                                                                             *
* makekey reads from STDIN & writes to STDOUT.  Input should consist of an 8  *
* character password string followed by a 2 character salt.  The salt charac- *
* ters should be taken from the letters a-z & A-Z, numerals, . & /.  The salt *
* is returned at the beginning of the encrypted output string.  Results are   *
* undefined if the input string is not 10 characters in total length.  Excess *
* input will be silently discarded.                                           *
*                                                                             *
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

// To compile on most Linux distros:

//	gcc -o makekey -m32 -lcrypt makekey.c

/*===========================================================================*/

/* global declarations */

#define	INPBUFSIZ	10			// input buffer size
#define	KEYSIZ		8			// input key size
#define	SALTSIZ		2			// input salt size

char	NUL='\0';				// null string terminator

void	collect(char *);			// collect input

/*===========================================================================*/

/* makekey: generate encrypted password */

int main(void) {

    char	*ec;				// encrypted string pointer
    char	inpbuf[INPBUFSIZ+1];		// input buffer
    char	key[KEYSIZ+1];			// key
    char	salt[SALTSIZ+1];		// salt
    int		eclen;				// encrypted string length

    collect(inpbuf);				// collect input
    strncpy(key,inpbuf,KEYSIZ);			// extract key
    strncpy(salt,inpbuf+KEYSIZ,SALTSIZ);	// extract salt
    key[KEYSIZ]=NUL;				// terminate key
    salt[SALTSIZ]=NUL;				// terminate salt
    eclen=(strlen(ec=crypt(key,salt)));		// encrypt
    if (write(STDOUT_FILENO,ec,eclen)!=eclen)
	perror("stdout");			// output <> input
    exit(0);					// done
}
/*===========================================================================*/

/* collect input string, at most INPBUFSIZ chars */

void collect(char *buf) {

    int		c,ct=0;

    while ((c=getchar()) != EOF) {
	if (ct<INPBUFSIZ) {
	    *(buf++)=c;
	    ct++;
	}
    }
    *(buf)=NUL;					// terminate input string
}
/*===========================================================================*/

/* copyright declaration for `what' command */

    const char *what[]={
	"@(#)makekey: BCS Technology Limited Password Encrypter",
	"@(#)",
	"@(#)Copyright (C)1994-2009 by BCS Technology Limited.  All rights",
	"@(#)reserved.  Permission granted to  use,  copy,  modify  and/or",
	"@(#)distribute this software,  providing  proper  attribution  is",
	"@(#)given and copyright notices remain intact.   This software is",
	"@(#)*NOT* in the public domain and has *NOT* been GPLed.",
	"@(#)",
	"@(#)BCS Technology Limited DOES NOT accept any responsibility for",
	"@(#)anything bad that might occur as a consequence  of  using  or",
	"@(#)modifying this software.  USE AT YOUR OWN RISK."
    };
/*===========================================================================*/

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