luksrku/cmdline.c

/*
	luksrku - Tool to remotely unlock LUKS disks using TLS.
	Copyright (C) 2016-2016 Johannes Bauer

	This file is part of luksrku.

	luksrku is free software; you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation; this program is ONLY licensed under
	version 3 of the License, later versions are explicitly excluded.

	luksrku is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with luksrku; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

	Johannes Bauer <JohannesBauer@gmx.de>
*/

#include <stdio.h>
#include <string.h>
#include <getopt.h>
#include <stdlib.h>

#include "cmdline.h"

enum longopts_t {
	LONGOPT_VERBOSE,
	LONGOPT_MODE_SERVER,
	LONGOPT_MODE_CLIENT,
	LONGOPT_PORT,
	LONGOPT_KEYDB
};

void print_syntax(void) {
	fprintf(stderr, "Help page here\n");
}

static void set_default_arguments(struct options_t *options) {
	memset(options, 0, sizeof(struct options_t));
	
	/* Default port :-) echo -n LUKS | md5sum | cut -c -5 */ 
	options->port = 23170;
}

static bool check_arguments(const struct options_t *options) {
	if (options->mode == UNDEFINED) {
		fprintf(stderr, "Must specify client or server mode.\n");
		return false;
	}
	
	if (options->keydbfile == NULL) {
		fprintf(stderr, "Must specify a key database file.\n");
		return false;
	}

	if ((options->port < 1) || (options->port > 65535)) {
		fprintf(stderr, "Valid port range is 1-65535.\n");
		return false;
	}
	
	return true;
}

bool parse_cmdline_arguments(struct options_t *options, int argc, char **argv) {
	set_default_arguments(options);

	struct option long_options[] = {
		{ "verbose",		no_argument,		0, LONGOPT_VERBOSE },
		{ "server-mode",	no_argument,		0, LONGOPT_MODE_SERVER },
		{ "client-mode",	no_argument,		0, LONGOPT_MODE_CLIENT },
		{ "port",			required_argument,	0, LONGOPT_PORT },
		{ "keydb",			required_argument,	0, LONGOPT_KEYDB },
		{ 0 }
	};

	bool success = true;
	bool parse = true;
	do {
		int c = getopt_long(argc, argv, "vscp:k:", long_options, NULL);
		switch (c) {
			case LONGOPT_VERBOSE:
			case 'v':
				options->verbose = true;
				break;
			
			case LONGOPT_MODE_SERVER:
			case 's':
				options->mode = SERVER_MODE;
				break;
			
			case LONGOPT_MODE_CLIENT:
			case 'c':
				options->mode = CLIENT_MODE;
				break;
			
			case LONGOPT_PORT:
			case 'p':
				options->port = atoi(optarg);
				break;
			
			case LONGOPT_KEYDB:
			case 'k':
				options->keydbfile = optarg;
				break;

			case -1:
				/* Out of arguments */
				parse = false;
				break;

			case '?':
				/* Syntax error */
				parse = false;
				success = false;
				break;

			default:
				fprintf(stderr, "Programming error: unexpected getopt return value %d.\n", c);
				parse = false;
				success = false;
				break;
		}
	} while (parse);

	return success && check_arguments(options);
}