X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=plugins%2Fcheck_dns.c;h=73b560ca665af001e16e211c1fec87cf5cda4548;hb=eaf3cb27f4b5bae479014a34c7decd3feedcf8fd;hp=492fa17629b8b5dffb3697313ef0640e209d4b58;hpb=edf60f6dceba48555f2534d9a217a8c5913ce029;p=nagiosplug.git

diff --git a/plugins/check_dns.c b/plugins/check_dns.c
index 492fa17..73b560c 100644
--- a/plugins/check_dns.c
+++ b/plugins/check_dns.c
@@ -1,35 +1,43 @@
-/******************************************************************************
-
- 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.
-
- LIMITATION: nslookup on Solaris 7 can return output over 2 lines, which will not 
- be picked up by this plugin
- 
- $Id$
-
-******************************************************************************/
+/*****************************************************************************
+* 
+* Nagios check_dns plugin
+* 
+* License: GPL
+* Copyright (c) 2000-2008 Nagios Plugins Development Team
+* 
+* Description:
+* 
+* This file contains the check_dns plugin
+* 
+* LIMITATION: nslookup on Solaris 7 can return output over 2 lines, which
+* will not be picked up by this plugin
+* 
+* 
+* 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 3 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, see <http://www.gnu.org/licenses/>.
+* 
+* 
+*****************************************************************************/
 
 const char *progname = "check_dns";
-const char *revision = "$Revision$";
-const char *copyright = "2000-2004";
+const char *copyright = "2000-2008";
 const char *email = "nagiosplug-devel@lists.sourceforge.net";
 
 #include "common.h"
-#include "popen.h"
 #include "utils.h"
+#include "utils_base.h"
 #include "netutils.h"
+#include "runcmd.h"
 
 int process_arguments (int, char **);
 int validate_arguments (void);
@@ -42,175 +50,211 @@ char query_address[ADDRESS_LENGTH] = "";
 char dns_server[ADDRESS_LENGTH] = "";
 char ptr_server[ADDRESS_LENGTH] = "";
 int verbose = FALSE;
-char expected_address[ADDRESS_LENGTH] = "";
-int match_expected_address = FALSE;
+char **expected_address = NULL;
+int expected_address_cnt = 0;
+
 int expect_authority = FALSE;
+thresholds *time_thresholds = NULL;
+
+static int
+qstrcmp(const void *p1, const void *p2)
+{
+	/* The actual arguments to this function are "pointers to
+	   pointers to char", but strcmp() arguments are "pointers
+	   to char", hence the following cast plus dereference */
+	return strcmp(* (char * const *) p1, * (char * const *) p2);
+}
+
 
 int
 main (int argc, char **argv)
 {
-	char *command_line = NULL;
-	char input_buffer[MAX_INPUT_BUFFER];
-	char *output = NULL;
-	char *address = NULL;
-	char *temp_buffer = NULL;
-	int non_authoritative = FALSE;
-	int result = STATE_UNKNOWN;
-	double elapsed_time;
-	long microsec;
-	struct timeval tv;
-	int multi_address;
-	int parse_address = FALSE; /* This flag scans for Address: but only after Name: */
-
-	setlocale (LC_ALL, "");
-	bindtextdomain (PACKAGE, LOCALEDIR);
-	textdomain (PACKAGE);
-
-	/* Set signal handling and alarm */
-	if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR) {
-		usage4 (_("Cannot catch SIGALRM"));
-	}
-
-	if (process_arguments (argc, argv) != TRUE) {
-		usage4 (_("Could not parse arguments"));
-	}
-
-	/* get the command to run */
-	asprintf (&command_line, "%s %s %s", NSLOOKUP_COMMAND, query_address, dns_server);
-
-	alarm (timeout_interval);
-	gettimeofday (&tv, NULL);
-
-	if (verbose)
-		printf ("%s\n", command_line);
-
-	/* run the command */
-	child_process = spopen (command_line);
-	if (child_process == NULL) {
-		printf (_("Could not open pipe: %s\n"), command_line);
-		return STATE_UNKNOWN;
-	}
-
-	child_stderr = fdopen (child_stderr_array[fileno (child_process)], "r");
-	if (child_stderr == NULL)
-		printf (_("Could not open stderr for %s\n"), command_line);
-
-	/* scan stdout */
-	while (fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_process)) {
-
-		if (verbose)
-			printf ("%s", input_buffer);
-
-		if (strstr (input_buffer, ".in-addr.arpa")) {
-			if ((temp_buffer = strstr (input_buffer, "name = ")))
-				address = strdup (temp_buffer + 7);
-			else {
-				output = strdup (_("Warning plugin error"));
-				result = STATE_WARNING;
-			}
-		}
-
-		/* the server is responding, we just got the host name... */
-		if (strstr (input_buffer, "Name:"))
-			parse_address = TRUE;
-		else if (parse_address == TRUE && (strstr (input_buffer, "Address:") ||
-		         strstr (input_buffer, "Addresses:"))) {
-			temp_buffer = index (input_buffer, ':');
-			temp_buffer++;
-
-			/* Strip leading spaces */
-			for (; *temp_buffer != '\0' && *temp_buffer == ' '; temp_buffer++)
-				/* NOOP */;
-			
-			strip(temp_buffer);
-			if (temp_buffer==NULL || strlen(temp_buffer)==0) {
-				die (STATE_CRITICAL,
-				     _("DNS CRITICAL - '%s' returned empty host name string\n"),
-				     NSLOOKUP_COMMAND);
-			}
-
-			if (address == NULL)
-				address = strdup (temp_buffer);
-			else
-				asprintf(&address, "%s,%s", address, temp_buffer);
-		}
-
-		else if (strstr (input_buffer, "Non-authoritative answer:")) {
-			non_authoritative = TRUE;
-		}
-
-		result = error_scan (input_buffer);
-		if (result != STATE_OK) {
-			output = strdup (1 + index (input_buffer, ':'));
-			strip (output);
-			break;
-		}
-
-	}
-
-	/* scan stderr */
-	while (fgets (input_buffer, MAX_INPUT_BUFFER - 1, child_stderr)) {
-		if (error_scan (input_buffer) != STATE_OK) {
-			result = max_state (result, error_scan (input_buffer));
-			output = strdup (1 + index (input_buffer, ':'));
-			strip (output);
-		}
-	}
-
-	/* close stderr */
-	(void) fclose (child_stderr);
-
-	/* close stdout */
-	if (spclose (child_process)) {
-		result = max_state (result, STATE_WARNING);
-		if (!strcmp (output, ""))
-			output = strdup (_("nslookup returned error status"));
-	}
-
-	/* If we got here, we should have an address string, 
-		 and we can segfault if we do not */
-	if (address==NULL || strlen(address)==0)
-		die (STATE_CRITICAL,
-		     _("DNS CRITICAL - '%s' output parsing exited with no address\n"),
-		     NSLOOKUP_COMMAND);
-
-	/* compare to expected address */
-	if (result == STATE_OK && match_expected_address && strcmp(address, expected_address)) {
-		result = STATE_CRITICAL;
-		asprintf(&output, _("expected %s but got %s"), expected_address, address);
-	}
-
-	/* check if authoritative */
-	if (result == STATE_OK && expect_authority && non_authoritative) {
-		result = STATE_CRITICAL;
-		asprintf(&output, _("server %s is not authoritative for %s"), dns_server, query_address);
-	}
-
-	microsec = deltime (tv);
-	elapsed_time = (double)microsec / 1.0e6;
-
-	if (result == STATE_OK) {
-		if (strchr (address, ',') == NULL)
-			multi_address = FALSE;
-		else
-			multi_address = TRUE;
-
-		printf ("DNS %s: ", _("OK"));
-		printf (_("%.3f seconds response time"), elapsed_time);
-		printf (_("%s returns %s"), query_address, address);
-		printf ("|%s\n", fperfdata ("time", elapsed_time, "s", FALSE, 0, FALSE, 0, TRUE, 0, FALSE, 0));
-	}
-	else if (result == STATE_WARNING)
-		printf (_("DNS WARNING - %s\n"),
-		        !strcmp (output, "") ? _(" Probably a non-existent host/domain") : output);
-	else if (result == STATE_CRITICAL)
-		printf (_("DNS CRITICAL - %s\n"),
-		        !strcmp (output, "") ? _(" Probably a non-existent host/domain") : output);
-	else
-		printf (_("DNS UNKNOW - %s\n"),
-		        !strcmp (output, "") ? _(" Probably a non-existent host/domain") : output);
-
-	return result;
+  char *command_line = NULL;
+  char input_buffer[MAX_INPUT_BUFFER];
+  char *address = NULL; /* comma seperated str with addrs/ptrs (sorted) */
+  char **addresses = NULL;
+  int n_addresses = 0;
+  char *msg = NULL;
+  char *temp_buffer = NULL;
+  int non_authoritative = FALSE;
+  int result = STATE_UNKNOWN;
+  double elapsed_time;
+  long microsec;
+  struct timeval tv;
+  int multi_address;
+  int parse_address = FALSE; /* This flag scans for Address: but only after Name: */
+  output chld_out, chld_err;
+  size_t i;
+
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  /* Set signal handling and alarm */
+  if (signal (SIGALRM, popen_timeout_alarm_handler) == SIG_ERR) {
+    usage_va(_("Cannot catch SIGALRM"));
+  }
+
+  /* Parse extra opts if any */
+  argv=np_extra_opts (&argc, argv, progname);
+
+  if (process_arguments (argc, argv) == ERROR) {
+    usage_va(_("Could not parse arguments"));
+  }
+
+  /* get the command to run */
+  asprintf (&command_line, "%s %s %s", NSLOOKUP_COMMAND, query_address, dns_server);
+
+  alarm (timeout_interval);
+  gettimeofday (&tv, NULL);
+
+  if (verbose)
+    printf ("%s\n", command_line);
+
+  /* run the command */
+  if((np_runcmd(command_line, &chld_out, &chld_err, 0)) != 0) {
+    msg = (char *)_("nslookup returned an error status");
+    result = STATE_WARNING;
+  }
+
+  /* scan stdout */
+  for(i = 0; i < chld_out.lines; i++) {
+    if (addresses == NULL)
+      addresses = malloc(sizeof(*addresses)*10);
+    else if (!(n_addresses % 10))
+      addresses = realloc(addresses,sizeof(*addresses) * (n_addresses + 10));
+
+    if (verbose)
+      puts(chld_out.line[i]);
+
+    if (strstr (chld_out.line[i], ".in-addr.arpa")) {
+      if ((temp_buffer = strstr (chld_out.line[i], "name = ")))
+        addresses[n_addresses++] = strdup (temp_buffer + 7);
+      else {
+        msg = (char *)_("Warning plugin error");
+        result = STATE_WARNING;
+      }
+    }
+
+    /* the server is responding, we just got the host name... */
+    if (strstr (chld_out.line[i], "Name:"))
+      parse_address = TRUE;
+    else if (parse_address == TRUE && (strstr (chld_out.line[i], "Address:") ||
+             strstr (chld_out.line[i], "Addresses:"))) {
+      temp_buffer = index (chld_out.line[i], ':');
+      temp_buffer++;
+
+      /* Strip leading spaces */
+      for (; *temp_buffer != '\0' && *temp_buffer == ' '; temp_buffer++)
+        /* NOOP */;
+
+      strip(temp_buffer);
+      if (temp_buffer==NULL || strlen(temp_buffer)==0) {
+        die (STATE_CRITICAL,
+             _("DNS CRITICAL - '%s' returned empty host name string\n"),
+             NSLOOKUP_COMMAND);
+      }
+
+      addresses[n_addresses++] = strdup(temp_buffer);
+    }
+    else if (strstr (chld_out.line[i], _("Non-authoritative answer:"))) {
+      non_authoritative = TRUE;
+    }
+
+
+    result = error_scan (chld_out.line[i]);
+    if (result != STATE_OK) {
+      msg = strchr (chld_out.line[i], ':');
+      if(msg) msg++;
+      break;
+    }
+  }
+
+  /* scan stderr */
+  for(i = 0; i < chld_err.lines; i++) {
+    if (verbose)
+      puts(chld_err.line[i]);
+
+    if (error_scan (chld_err.line[i]) != STATE_OK) {
+      result = max_state (result, error_scan (chld_err.line[i]));
+      msg = strchr(input_buffer, ':');
+      if(msg) msg++;
+    }
+  }
+
+  if (addresses) {
+    int i,slen;
+    char *adrp;
+    qsort(addresses, n_addresses, sizeof(*addresses), qstrcmp);
+    for(i=0, slen=1; i < n_addresses; i++) {
+      slen += strlen(addresses[i])+1;
+    }
+    adrp = address = malloc(slen);
+    for(i=0; i < n_addresses; i++) {
+      if (i) *adrp++ = ',';
+      strcpy(adrp, addresses[i]);
+      adrp += strlen(addresses[i]);
+    }
+    *adrp = 0;
+  } else
+    die (STATE_CRITICAL,
+         _("DNS CRITICAL - '%s' msg parsing exited with no address\n"),
+         NSLOOKUP_COMMAND);
+
+  /* compare to expected address */
+  if (result == STATE_OK && expected_address_cnt > 0) {
+    result = STATE_CRITICAL;
+    temp_buffer = "";
+    for (i=0; i<expected_address_cnt; i++) {
+      /* check if we get a match and prepare an error string */
+      if (strcmp(address, expected_address[i]) == 0) result = STATE_OK;
+      asprintf(&temp_buffer, "%s%s; ", temp_buffer, expected_address[i]);
+    }
+    if (result == STATE_CRITICAL) {
+      /* Strip off last semicolon... */
+      temp_buffer[strlen(temp_buffer)-2] = '\0';
+      asprintf(&msg, _("expected '%s' but got '%s'"), temp_buffer, address);
+    }
+  }
+
+  /* check if authoritative */
+  if (result == STATE_OK && expect_authority && non_authoritative) {
+    result = STATE_CRITICAL;
+    asprintf(&msg, _("server %s is not authoritative for %s"), dns_server, query_address);
+  }
+
+  microsec = deltime (tv);
+  elapsed_time = (double)microsec / 1.0e6;
+
+  if (result == STATE_OK) {
+    if (strchr (address, ',') == NULL)
+      multi_address = FALSE;
+    else
+      multi_address = TRUE;
+
+    result = get_status(elapsed_time, time_thresholds);
+    if (result == STATE_OK) {
+      printf ("DNS %s: ", _("OK"));
+    } else if (result == STATE_WARNING) {
+      printf ("DNS %s: ", _("WARNING"));
+    } else if (result == STATE_CRITICAL) {
+      printf ("DNS %s: ", _("CRITICAL"));
+    }
+    printf (ngettext("%.3f second response time", "%.3f seconds response time", elapsed_time), elapsed_time);
+    printf (_(". %s returns %s"), query_address, address);
+    printf ("|%s\n", fperfdata ("time", elapsed_time, "s", FALSE, 0, FALSE, 0, TRUE, 0, FALSE, 0));
+  }
+  else if (result == STATE_WARNING)
+    printf (_("DNS WARNING - %s\n"),
+            !strcmp (msg, "") ? _(" Probably a non-existent host/domain") : msg);
+  else if (result == STATE_CRITICAL)
+    printf (_("DNS CRITICAL - %s\n"),
+            !strcmp (msg, "") ? _(" Probably a non-existent host/domain") : msg);
+  else
+    printf (_("DNS UNKNOWN - %s\n"),
+            !strcmp (msg, "") ? _(" Probably a non-existent host/domain") : msg);
+
+  return result;
 }
 
 
@@ -219,212 +263,226 @@ int
 error_scan (char *input_buffer)
 {
 
-	/* the DNS lookup timed out */
-	if (strstr (input_buffer, "Note: nslookup is deprecated and may be removed from future releases.") ||
-	    strstr (input_buffer, "Consider using the `dig' or `host' programs instead.  Run nslookup with") ||
-	    strstr (input_buffer, "the `-sil[ent]' option to prevent this message from appearing."))
-		return STATE_OK;
-
-	/* DNS server is not running... */
-	else if (strstr (input_buffer, "No response from server"))
-		die (STATE_CRITICAL, _("No response from DNS %s\n"), dns_server);
-
-	/* Host name is valid, but server doesn't have records... */
-	else if (strstr (input_buffer, "No records"))
-		die (STATE_CRITICAL, _("DNS %s has no records\n"), dns_server);
-
-	/* Connection was refused */
-	else if (strstr (input_buffer, "Connection refused") ||
-	         strstr (input_buffer, "Refused") ||
-	         (strstr (input_buffer, "** server can't find") &&
-	          strstr (input_buffer, ": REFUSED")))
-		die (STATE_CRITICAL, _("Connection to DNS %s was refused\n"), dns_server);
-
-	/* Host or domain name does not exist */
-	else if (strstr (input_buffer, "Non-existent") ||
-	         strstr (input_buffer, "** server can't find") ||
-	         strstr (input_buffer,"NXDOMAIN"))
-		die (STATE_CRITICAL, _("Domain %s was not found by the server\n"), query_address);
-
-	/* Network is unreachable */
-	else if (strstr (input_buffer, "Network is unreachable"))
-		die (STATE_CRITICAL, _("Network is unreachable\n"));
-
-	/* Internal server failure */
-	else if (strstr (input_buffer, "Server failure"))
-		die (STATE_CRITICAL, _("DNS failure for %s\n"), dns_server);
-
-	/* Request error or the DNS lookup timed out */
-	else if (strstr (input_buffer, "Format error") ||
-	         strstr (input_buffer, "Timed out"))
-		return STATE_WARNING;
-
-	return STATE_OK;
+  /* the DNS lookup timed out */
+  if (strstr (input_buffer, _("Note: nslookup is deprecated and may be removed from future releases.")) ||
+      strstr (input_buffer, _("Consider using the `dig' or `host' programs instead.  Run nslookup with")) ||
+      strstr (input_buffer, _("the `-sil[ent]' option to prevent this message from appearing.")))
+    return STATE_OK;
+
+  /* DNS server is not running... */
+  else if (strstr (input_buffer, "No response from server"))
+    die (STATE_CRITICAL, _("No response from DNS %s\n"), dns_server);
+
+  /* Host name is valid, but server doesn't have records... */
+  else if (strstr (input_buffer, "No records"))
+    die (STATE_CRITICAL, _("DNS %s has no records\n"), dns_server);
+
+  /* Connection was refused */
+  else if (strstr (input_buffer, "Connection refused") ||
+     strstr (input_buffer, "Couldn't find server") ||
+           strstr (input_buffer, "Refused") ||
+           (strstr (input_buffer, "** server can't find") &&
+            strstr (input_buffer, ": REFUSED")))
+    die (STATE_CRITICAL, _("Connection to DNS %s was refused\n"), dns_server);
+
+  /* Query refused (usually by an ACL in the namserver) */
+  else if (strstr (input_buffer, "Query refused"))
+    die (STATE_CRITICAL, _("Query was refused by DNS server at %s\n"), dns_server);
+
+  /* No information (e.g. nameserver IP has two PTR records) */
+  else if (strstr (input_buffer, "No information"))
+    die (STATE_CRITICAL, _("No information returned by DNS server at %s\n"), dns_server);
+
+  /* Host or domain name does not exist */
+  else if (strstr (input_buffer, "Non-existent") ||
+           strstr (input_buffer, "** server can't find") ||
+     strstr (input_buffer,"NXDOMAIN"))
+    die (STATE_CRITICAL, _("Domain %s was not found by the server\n"), query_address);
+
+  /* Network is unreachable */
+  else if (strstr (input_buffer, "Network is unreachable"))
+    die (STATE_CRITICAL, _("Network is unreachable\n"));
+
+  /* Internal server failure */
+  else if (strstr (input_buffer, "Server failure"))
+    die (STATE_CRITICAL, _("DNS failure for %s\n"), dns_server);
+
+  /* Request error or the DNS lookup timed out */
+  else if (strstr (input_buffer, "Format error") ||
+           strstr (input_buffer, "Timed out"))
+    return STATE_WARNING;
+
+  return STATE_OK;
 
 }
 
 
-
 /* process command-line arguments */
 int
 process_arguments (int argc, char **argv)
 {
-	int c;
-
-	int opt_index = 0;
-	static struct option long_opts[] = {
-		{"help", no_argument, 0, 'h'},
-		{"version", no_argument, 0, 'V'},
-		{"verbose", no_argument, 0, 'v'},
-		{"timeout", required_argument, 0, 't'},
-		{"hostname", required_argument, 0, 'H'},
-		{"server", required_argument, 0, 's'},
-		{"reverse-server", required_argument, 0, 'r'},
-		{"expected-address", required_argument, 0, 'a'},
-		{"expect-authority", no_argument, 0, 'A'},
-		{0, 0, 0, 0}
-	};
-
-	if (argc < 2)
-		return ERROR;
-
-	for (c = 1; c < argc; c++)
-		if (strcmp ("-to", argv[c]) == 0)
-			strcpy (argv[c], "-t");
-
-	while (1) {
-		c = getopt_long (argc, argv, "hVvAt:H:s:r:a:", long_opts, &opt_index);
-
-		if (c == -1 || c == EOF)
-			break;
-
-		switch (c) {
-		case '?': /* args not parsable */
-			printf (_("%s: Unknown argument: %s\n\n"), progname, optarg);
-			print_usage ();
-			exit (STATE_UNKNOWN);
-		case 'h': /* help */
-			print_help ();
-			exit (STATE_OK);
-		case 'V': /* version */
-			print_revision (progname, revision);
-			exit (STATE_OK);
-		case 'v': /* version */
-			verbose = TRUE;
-			break;
-		case 't': /* timeout period */
-			timeout_interval = atoi (optarg);
-			break;
-		case 'H': /* hostname */
-			if (strlen (optarg) >= ADDRESS_LENGTH)
-				die (STATE_UNKNOWN, _("Input buffer overflow\n"));
-			strcpy (query_address, optarg);
-			break;
-		case 's': /* server name */
-			/* TODO: this is_host check is probably unnecessary. */
-			/* Better to confirm nslookup response matches */
-			if (is_host (optarg) == FALSE) {
-				printf (_("Invalid hostname/address\n\n"));
-				print_usage ();
-				exit (STATE_UNKNOWN);
-			}
-			if (strlen (optarg) >= ADDRESS_LENGTH)
-				die (STATE_UNKNOWN, _("Input buffer overflow\n"));
-			strcpy (dns_server, optarg);
-			break;
-		case 'r': /* reverse server name */
-			/* TODO: Is this is_host necessary? */
-			if (is_host (optarg) == FALSE) {
-				usage2 (_("Invalid hostname/address"), optarg);
-			}
-			if (strlen (optarg) >= ADDRESS_LENGTH)
-				die (STATE_UNKNOWN, _("Input buffer overflow\n"));
-			strcpy (ptr_server, optarg);
-			break;
-		case 'a': /* expected address */
-			if (strlen (optarg) >= ADDRESS_LENGTH)
-				die (STATE_UNKNOWN, _("Input buffer overflow\n"));
-			strcpy (expected_address, optarg);
-			match_expected_address = TRUE;
-			break;
-		case 'A': /* expect authority */
-			expect_authority = TRUE;
-			break;
-		}
-	}
-
-	c = optind;
-	if (strlen(query_address)==0 && c<argc) {
-		if (strlen(argv[c])>=ADDRESS_LENGTH)
-			die (STATE_UNKNOWN, _("Input buffer overflow\n"));
-		strcpy (query_address, argv[c++]);
-	}
-
-	if (strlen(dns_server)==0 && c<argc) {
-		/* TODO: See -s option */
-		if (is_host(argv[c]) == FALSE) {
-			printf (_("Invalid hostname/address: %s\n\n"), argv[c]);
-			return ERROR;
-		}
-		if (strlen(argv[c]) >= ADDRESS_LENGTH)
-			die (STATE_UNKNOWN, _("Input buffer overflow\n"));
-		strcpy (dns_server, argv[c++]);
-	}
-
-	return validate_arguments ();
+  int c;
+  char *warning = NULL;
+  char *critical = NULL;
+
+  int opt_index = 0;
+  static struct option long_opts[] = {
+    {"help", no_argument, 0, 'h'},
+    {"version", no_argument, 0, 'V'},
+    {"verbose", no_argument, 0, 'v'},
+    {"timeout", required_argument, 0, 't'},
+    {"hostname", required_argument, 0, 'H'},
+    {"server", required_argument, 0, 's'},
+    {"reverse-server", required_argument, 0, 'r'},
+    {"expected-address", required_argument, 0, 'a'},
+    {"expect-authority", no_argument, 0, 'A'},
+    {"warning", required_argument, 0, 'w'},
+    {"critical", required_argument, 0, 'c'},
+    {0, 0, 0, 0}
+  };
+
+  if (argc < 2)
+    return ERROR;
+
+  for (c = 1; c < argc; c++)
+    if (strcmp ("-to", argv[c]) == 0)
+      strcpy (argv[c], "-t");
+
+  while (1) {
+    c = getopt_long (argc, argv, "hVvAt:H:s:r:a:w:c:", long_opts, &opt_index);
+
+    if (c == -1 || c == EOF)
+      break;
+
+    switch (c) {
+    case 'h': /* help */
+      print_help ();
+      exit (STATE_OK);
+    case 'V': /* version */
+      print_revision (progname, NP_VERSION);
+      exit (STATE_OK);
+    case 'v': /* version */
+      verbose = TRUE;
+      break;
+    case 't': /* timeout period */
+      timeout_interval = atoi (optarg);
+      break;
+    case 'H': /* hostname */
+      if (strlen (optarg) >= ADDRESS_LENGTH)
+        die (STATE_UNKNOWN, _("Input buffer overflow\n"));
+      strcpy (query_address, optarg);
+      break;
+    case 's': /* server name */
+      /* TODO: this host_or_die check is probably unnecessary.
+       * Better to confirm nslookup response matches */
+      host_or_die(optarg);
+      if (strlen (optarg) >= ADDRESS_LENGTH)
+        die (STATE_UNKNOWN, _("Input buffer overflow\n"));
+      strcpy (dns_server, optarg);
+      break;
+    case 'r': /* reverse server name */
+      /* TODO: Is this host_or_die necessary? */
+      host_or_die(optarg);
+      if (strlen (optarg) >= ADDRESS_LENGTH)
+        die (STATE_UNKNOWN, _("Input buffer overflow\n"));
+      strcpy (ptr_server, optarg);
+      break;
+    case 'a': /* expected address */
+      if (strlen (optarg) >= ADDRESS_LENGTH)
+        die (STATE_UNKNOWN, _("Input buffer overflow\n"));
+      expected_address = (char **)realloc(expected_address, (expected_address_cnt+1) * sizeof(char**));
+      expected_address[expected_address_cnt] = strdup(optarg);
+      expected_address_cnt++;
+      break;
+    case 'A': /* expect authority */
+      expect_authority = TRUE;
+      break;
+    case 'w':
+      warning = optarg;
+      break;
+    case 'c':
+      critical = optarg;
+      break;
+    default: /* args not parsable */
+      usage5();
+    }
+  }
+
+  c = optind;
+  if (strlen(query_address)==0 && c<argc) {
+    if (strlen(argv[c])>=ADDRESS_LENGTH)
+      die (STATE_UNKNOWN, _("Input buffer overflow\n"));
+    strcpy (query_address, argv[c++]);
+  }
+
+  if (strlen(dns_server)==0 && c<argc) {
+    /* TODO: See -s option */
+    host_or_die(argv[c]);
+    if (strlen(argv[c]) >= ADDRESS_LENGTH)
+      die (STATE_UNKNOWN, _("Input buffer overflow\n"));
+    strcpy (dns_server, argv[c++]);
+  }
+
+  set_thresholds(&time_thresholds, warning, critical);
+
+  return validate_arguments ();
 }
 
 
-
 int
 validate_arguments ()
 {
-	if (query_address[0] == 0)
-		return ERROR;
-	else
-		return OK;
-}
+  if (query_address[0] == 0)
+    return ERROR;
 
+  return OK;
+}
 
 
 void
 print_help (void)
 {
-	print_revision (progname, revision);
+  print_revision (progname, NP_VERSION);
 
-	printf ("Copyright (c) 1999 Ethan Galstad <nagios@nagios.org>\n");
-	printf (COPYRIGHT, copyright, email);
+  printf ("Copyright (c) 1999 Ethan Galstad <nagios@nagios.org>\n");
+  printf (COPYRIGHT, copyright, email);
 
-	print_usage ();
+  printf ("%s\n", _("This plugin uses the nslookup program to obtain the IP address for the given host/domain query."));
+  printf ("%s\n", _("An optional DNS server to use may be specified."));
+  printf ("%s\n", _("If no DNS server is specified, the default server(s) specified in /etc/resolv.conf will be used."));
 
-	printf (_(UT_HELP_VRSN));
+  printf ("\n\n");
 
-	printf (_("\
--H, --hostname=HOST\n\
-   The name or address you want to query\n\
--s, --server=HOST\n\
-   Optional DNS server you want to use for the lookup\n\
--a, --expected-address=IP-ADDRESS\n\
-   Optional IP address you expect the DNS server to return\n\
--A, --expect-authority\n\
-   Optionally expect the DNS server to be authoritative for the lookup\n"));
+  print_usage ();
 
-	printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
+  printf (UT_HELP_VRSN);
+  printf (UT_EXTRA_OPTS);
 
-	printf (_("\n\
-This plugin uses the nslookup program to obtain the IP address\n\
-for the given host/domain query.  A optional DNS server to use may\n\
-be specified.  If no DNS server is specified, the default server(s)\n\
-specified in /etc/resolv.conf will be used.\n"));
+  printf (" -H, --hostname=HOST\n");
+  printf ("    %s\n", _("The name or address you want to query"));
+  printf (" -s, --server=HOST\n");
+  printf ("    %s\n", _("Optional DNS server you want to use for the lookup"));
+  printf (" -a, --expected-address=IP-ADDRESS|HOST\n");
+  printf ("    %s\n", _("Optional IP-ADDRESS you expect the DNS server to return. HOST must end with"));
+  printf ("    %s\n", _("a dot (.). This option can be repeated multiple times (Returns OK if any"));
+  printf ("    %s\n", _("value match). If multiple addresses are returned at once, you have to match"));
+  printf ("    %s\n", _("the whole string of addresses separated with commas (sorted alphabetically)."));
+  printf (" -A, --expect-authority\n");
+  printf ("    %s\n", _("Optionally expect the DNS server to be authoritative for the lookup"));
+  printf (" -w, --warning=seconds\n");
+  printf ("    %s\n", _("Return warning if elapsed time exceeds value. Default off"));
+  printf (" -c, --critical=seconds\n");
+  printf ("    %s\n", _("Return critical if elapsed time exceeds value. Default off"));
 
-	printf (_(UT_SUPPORT));
-}
+  printf (UT_TIMEOUT, DEFAULT_SOCKET_TIMEOUT);
 
+  printf (UT_SUPPORT);
+}
 
 
 void
 print_usage (void)
 {
-	printf ("\
-Usage: %s -H host [-s server] [-a expected-address] [-A] [-t timeout]\n", progname);
+  printf ("%s\n", _("Usage:"));
+  printf ("%s -H host [-s server] [-a expected-address] [-A] [-t timeout] [-w warn] [-c crit]\n", progname);
 }