/* * $OpenBSD: skey.c,v 1.3 1996/09/27 15:41:36 millert Exp $*/
/*
 * S/KEY v1.1b (skey.c)
 *
 * Authors:
 *          Neil M. Haller <nmh@thumper.bellcore.com>
 *          Philip R. Karn <karn@chicago.qualcomm.com>
 *          John S. Walden <jsw@thumper.bellcore.com>
 *          Scott Chasin <chasin@crimelab.com>
 *
 *
 * Stand-alone program for computing responses to S/Key challenges.
 * Takes the iteration count and seed as command line args, prompts
 * for the user's key, and produces both word and hex format responses.
 *
 * Usage example:
 *	>skey 88 ka9q2
 *	Enter password:
 *	OMEN US HORN OMIT BACK AHOY
 *	>
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <err.h>
#include <unistd.h>
#include <skey.h>

void    usage __P((char *));

int
main(argc, argv)
	int	argc;
	char	*argv[];
{
	int     n, i, cnt = 1, pass = 0, hexmode = 0;
	char    passwd[256], key[8], buf[33], *seed, *slash;

	while ((i = getopt(argc, argv, "n:p:x45")) != EOF) {
		switch (i) {
		case 'n':
			cnt = atoi(optarg);
			break;
		case 'p':
			strcpy(passwd, optarg);
			pass = 1;
			break;
		case 'x':
			hexmode = 1;
			break;
		case '4':
			skey_set_MDX(4);
			break;
		case '5':
			skey_set_MDX(5);
			break;
		}
	}

	/* could be in the form <number>/<seed> */

	if (argc <= optind + 1) {
		/* look for / in it */
		if (argc <= optind)
			usage(argv[0]);
		slash = strchr(argv[optind], '/');
		if (slash == NULL)
			usage(argv[0]);
		*slash++ = '\0';
		seed = slash;

		if ((n = atoi(argv[optind])) < 0) {
			warnx("%s not positive", argv[optind]);
			usage(argv[0]);
		}
	} else {
		if ((n = atoi(argv[optind])) < 0) {
			warnx("%s not positive", argv[optind]);
			usage(argv[0]);
		}
		seed = argv[++optind];
	}

	/* Get user's secret password */
	if (!pass) {
		(void)fputs("Reminder - Do not use this program while logged in via telnet or rlogin.\n", stderr);
		(void)fputs("Enter secret password: ", stderr);
		readpass(passwd, sizeof(passwd));
	}
	rip(passwd);

	/* Crunch seed and password into starting key */
	if (keycrunch(key, seed, passwd) != 0)
		errx(1, "key crunch failed");

	if (cnt == 1) {
		while (n-- != 0)
			f(key);
		(void)puts(hexmode ? put8(buf, key) : btoe(buf, key));
	} else {
		for (i = 0; i <= n - cnt; i++)
			f(key);
		for (; i <= n; i++) {
			if (hexmode)
				(void)printf("%d: %-29s  %s\n", i,
				    btoe(buf, key), put8(buf, key));
			else
				(void)printf("%d: %-29s\n", i, btoe(buf, key));
			f(key);
		}
	}
	exit(0);
}

void
usage(s)
	char   *s;
{
	(void)fprintf(stderr, "Usage: %s [-x] [-4|-5] [-n count] [-p password ] sequence# [/] key", s);
	exit(1);
}