/******************************************************************************
 *
 * CHECK_NNTP.C
 *
 * Program: NNTP plugin for Nagios
 * License: GPL
 * Copyright (c) 1999 Ethan Galstad (nagios@nagios.org)
 *
 * $Id$
 *
 * Description:
 *
 * This plugin will attempt to open an NNTP connection with the host.
 * Successul connects return STATE_OK, refusals and timeouts return
 * STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful
 * connects, but incorrect reponse messages from the host result in
 * STATE_WARNING return values.  An invalid newsgroup (if the -g
 * option is used) results in a STATE_WARNING value.
 *
 * License Information:
 *
 * This program 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *****************************************************************************/

#include "config.h"
#include "common.h"
#include "netutils.h"
#include "utils.h"

#define PROGNAME "check_nntp"

#define PORT 119
#define EXPECT1A "200"					/* posting allowed */
#define EXPECT1B "201"					/* posting not allowed */
#define EXPECT "NNTP"
#define QUIT "QUIT\r\n"
#define MODEREADER "MODE READER\r\n"

int process_arguments (int, char **);
int call_getopt (int, char **);
int validate_arguments (void);
int check_disk (int usp, int free_disk);
void print_help (void);
void print_usage (void);

int server_port = PORT;
char *server_expect = NULL;
char *server_address = NULL;
char *newsgroup = NULL;
int check_newsgroup = FALSE;
int send_modereader = FALSE;
int warning_time = 0;
int check_warning_time = FALSE;
int critical_time = 0;
int check_critical_time = FALSE;
int verbose = FALSE;


int
main (int argc, char **argv)
{
	char buffer[MAX_INPUT_BUFFER] = "";
	int sd;
	int result;
	int recv_result;

	if (process_arguments (argc, argv) != OK)
		usage ("Invalid command arguments supplied\n");

	/* initialize alarm signal handling */
	signal (SIGALRM, socket_timeout_alarm_handler);

	/* set socket timeout */
	alarm (socket_timeout);

	/* try to connect to the host at the given port number */
	time (&start_time);
	result = my_tcp_connect (server_address, server_port, &sd);

	/* we connected */
	if (result == STATE_OK) {

		/* watch for the NNTP connection string */
		recv_result = recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0);

		/* return a WARNING status if we couldn't read any data */
		if (recv_result == -1) {

			printf ("recv() failed\n");
			result = STATE_WARNING;

		}
		else {

			/* strip carriage returns from buffer */
			strip (buffer);

			/* make sure we find the response we are looking for */
			if (strstr (buffer, EXPECT1A) != buffer
					&& strstr (buffer, EXPECT1B) != buffer) {
				printf ("Invalid NNTP response received from host: %s\n", buffer);
				result = STATE_WARNING;
			}

			/* optionally send mode reader */
			/* added 2000-09-18 by Andreas M. Kirchwitz <amk@krell.snafu.de> including some other minor fixes */
			if (send_modereader == TRUE) {
				send (sd, MODEREADER, strlen (MODEREADER), 0);
				recv_result = recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0);
				if (recv_result == -1)
					strcpy (buffer, "");
				else
					buffer[recv_result] = 0;
				strip (buffer);
				if ((strstr (buffer, EXPECT1A) != buffer)
						&& (strstr (buffer, EXPECT1B) != buffer)) {
					printf ("Unexpected NNTP response received from host");
					result = STATE_WARNING;
				}
			}

			if (server_expect && !strstr (buffer, server_expect)) {
				printf ("Invalid NNTP header received from host: %s\n", buffer);
				result = STATE_WARNING;
			}

			if (check_newsgroup == TRUE) {
				sprintf (buffer, "GROUP %s\r\n", newsgroup);
				send (sd, buffer, strlen (buffer), 0);
				recv_result = recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0);
				if (recv_result == -1)
					strcpy (buffer, "");
				else
					buffer[recv_result] = 0;
				strip (buffer);
				if (strstr (buffer, "211") != buffer) {
					printf ("NNTP problem - newsgroup '%s' not found\n", newsgroup);
					result = STATE_WARNING;
				}
			}

			if (result == STATE_OK) {
				time (&end_time);
				if (check_critical_time == TRUE
						&& (end_time - start_time) > critical_time) result =
						STATE_CRITICAL;
				else if (check_warning_time == TRUE
								 && (end_time - start_time) > warning_time) result =
						STATE_WARNING;
				if (verbose)
					printf ("NNTP %s - %d sec. response time, %s\n",
									(result == STATE_OK) ? "ok" : "problem",
									(int) (end_time - start_time), buffer);
				else
					printf ("NNTP %s - %d second response time\n",
									(result == STATE_OK) ? "ok" : "problem",
									(int) (end_time - start_time));
			}

		}

		/* close the connection */
		send (sd, QUIT, strlen (QUIT), 0);
		close (sd);

	}

	/* reset the alarm timeout */
	alarm (0);

	return result;
}






/* process command-line arguments */
int
process_arguments (int argc, char **argv)
{
	int c;

	if (argc < 2)
		return ERROR;

	for (c = 1; c < argc; c++) {
		if (strcmp ("-to", argv[c]) == 0)
			strcpy (argv[c], "-t");
		else if (strcmp ("-wt", argv[c]) == 0)
			strcpy (argv[c], "-w");
		else if (strcmp ("-ct", argv[c]) == 0)
			strcpy (argv[c], "-c");
	}



	c = 0;
	while ((c += (call_getopt (argc - c, &argv[c]))) < argc) {

		if (is_option (argv[c]))
			continue;

		if (server_address == NULL) {
			if (is_host (argv[c])) {
				server_address = argv[c];
			}
			else {
				usage ("Invalid host name");
			}
		}
	}

	if (server_address == NULL)
		server_address = strscpy (NULL, "127.0.0.1");

/*  	if (server_expect==NULL) */
/*  		server_expect=strscpy(NULL,EXPECT); */

	return validate_arguments ();
}






int
call_getopt (int argc, char **argv)
{
	int c, i = 0;

#ifdef HAVE_GETOPT_H
	int option_index = 0;
	static struct option long_options[] = {
		{"hostname", required_argument, 0, 'H'},
		{"expect", required_argument, 0, 'e'},
		{"critical", required_argument, 0, 'c'},
		{"warning", required_argument, 0, 'w'},
		{"port", required_argument, 0, 'P'},
		{"modereader", required_argument, 0, 'M'},
		{"verbose", no_argument, 0, 'v'},
		{"version", no_argument, 0, 'V'},
		{"help", no_argument, 0, 'h'},
		{0, 0, 0, 0}
	};
#endif

	while (1) {
#ifdef HAVE_GETOPT_H
		c =
			getopt_long (argc, argv, "+hVMvt:p:e:c:w:H:", long_options,
									 &option_index);
#else
		c = getopt (argc, argv, "+?hVMvt:p:e:c:w:H:");
#endif

		i++;

		if (c == -1 || c == EOF || c == 1)
			break;

		switch (c) {
		case 't':
		case 'p':
		case 'e':
		case 'c':
		case 'w':
		case 'H':
			i++;
		}

		switch (c) {
		case 'H':									/* hostname */
			if (is_host (optarg)) {
				server_address = optarg;
			}
			else {
				usage ("Invalid host name\n");
			}
			break;
		case 'p':									/* port */
			if (is_intpos (optarg)) {
				server_port = atoi (optarg);
			}
			else {
				usage ("Server port must be a positive integer\n");
			}
			break;
		case 'M':									/* mode reader */
			send_modereader = TRUE;
			break;
		case 'e':									/* expect */
			server_expect = optarg;
			break;
		case 'g':									/* newsgroup */
			newsgroup = optarg;
			check_newsgroup = TRUE;
			break;
		case 'c':									/* critical time threshold */
			if (is_intnonneg (optarg)) {
				critical_time = atoi (optarg);
				check_critical_time = TRUE;
			}
			else {
				usage ("Critical time must be a nonnegative integer\n");
			}
			break;
		case 'w':									/* warning time threshold */
			if (is_intnonneg (optarg)) {
				warning_time = atoi (optarg);
				check_warning_time = TRUE;
			}
			else {
				usage ("Warning time must be a nonnegative integer\n");
			}
			break;
		case 'v':									/* verbose */
			verbose = TRUE;
			break;
		case 't':									/* timeout */
			if (is_intnonneg (optarg)) {
				socket_timeout = atoi (optarg);
			}
			else {
				usage ("Time interval must be a nonnegative integer\n");
			}
			break;
		case 'V':									/* version */
			print_revision (PROGNAME, "$Revision$");
			exit (STATE_OK);
		case 'h':									/* help */
			print_help ();
			exit (STATE_OK);
		case '?':									/* help */
			usage ("Invalid argument\n");
		}
	}
	return i;
}





int
validate_arguments (void)
{
	return OK;
}





void
print_help (void)
{
	print_revision (PROGNAME, "$Revision$");
	printf
		("Copyright (c) 2000 Ethan Galstad/Karl DeBisschop\n\n"
		 "This plugin tests the NNTP service on the specified host.\n\n");
	print_usage ();
	printf
		("\nOptions:\n"
		 " -H, --hostname=STRING or IPADDRESS\n"
		 "   Check server on the indicated host\n"
		 " -p, --port=INTEGER\n"
		 "   Make connection on the indicated port (default: %d)\n"
		 " -e, --expect=STRING\n"
		 "   String to expect in first line of server response (default: %s)\n"
		 " -g, --group=STRING\n"
		 "   Newsgroup to poll\n"
		 " -w, --warning=INTEGER\n"
		 "   Seconds necessary to result in a warning status\n"
		 " -c, --critical=INTEGER\n"
		 "   Seconds necessary to result in a critical status\n"
		 " -t, --timeout=INTEGER\n"
		 "   Seconds before connection attempt times out (default: %d)\n"
		 " -M\n"
		 "   Send \"MODE READER\" after initial connect.\n"
		 " -v, --verbose\n"
		 "   Print extra information (command-line use only)\n"
		 " -h, --help\n"
		 "   Print detailed help screen\n"
		 " -V, --version\n"
		 "   Print version information\n\n",
		 PORT, EXPECT, DEFAULT_SOCKET_TIMEOUT);
	support ();
}





void
print_usage (void)
{
	printf
		("Usage: %s -H host [-e expect] [-g group] [-p port] [-w warn] [-c crit]\n"
		 "            [-t timeout] [-v]\n"
		 "       %s --help\n"
		 "       %s --version\n", PROGNAME, PROGNAME, PROGNAME);
}