1 /******************************************************************************
2 *
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2 of the License, or
6 * (at your option) any later version.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
16 *
17 *****************************************************************************/
19 const char *progname = "check_smtp";
20 const char *revision = "$Revision$";
21 const char *copyright = "1999-2003";
22 const char *authors = "Nagios Plugin Development Team";
23 const char *email = "nagiosplug-devel@lists.sourceforge.net";
25 const char *summary = "\
26 This plugin will attempt to open an SMTP connection with the host.\n";
28 const char *description = "\
29 Successul connects return STATE_OK, refusals and timeouts return\n\
30 STATE_CRITICAL, other errors return STATE_UNKNOWN. Successful\n\
31 connects, but incorrect reponse messages from the host result in\n\
32 STATE_WARNING return values.\n";
34 const char *option_summary = "\
35 -H host [-p port] [-e expect] [-C command] [-f from addr]\n\
36 [-w warn] [-c crit] [-t timeout] [-n] [-v]";
38 const char *options = "\
39 -H, --hostname=STRING or IPADDRESS\n\
40 Check server on the indicated host\n\
41 -p, --port=INTEGER\n\
42 Make connection on the indicated port (default: %d)\n\
43 -e, --expect=STRING\n\
44 String to expect in first line of server response (default: '%s')\n\
45 -n, nocommand\n\
46 Suppress SMTP command\n\
47 -C, --command=STRING\n\
48 SMTP command (default: '%s')\n\
49 -f, --from=STRING\n\
50 FROM-address to include in MAIL command, required by Exchange 2000\n\
51 (default: '%s')\n\
52 -w, --warning=INTEGER\n\
53 Seconds necessary to result in a warning status\n\
54 -c, --critical=INTEGER\n\
55 Seconds necessary to result in a critical status\n\
56 -t, --timeout=INTEGER\n\
57 Seconds before connection attempt times out (default: %d)\n\
58 -v, --verbose\n\
59 Print extra information (command-line use only)\n\
60 -h, --help\n\
61 Print detailed help screen\n\
62 -V, --version\n\
63 Print version information\n\n";
65 enum {
66 SMTP_PORT = 25
67 };
68 const char *SMTP_EXPECT = "220";
69 const char *SMTP_HELO = "HELO ";
70 const char *SMTP_QUIT = "QUIT\r\n";
72 #include "config.h"
73 #include "common.h"
74 #include "netutils.h"
75 #include "utils.h"
77 int process_arguments (int, char **);
78 int validate_arguments (void);
79 void print_help (void);
80 void print_usage (void);
82 int server_port = SMTP_PORT;
83 char *server_address = NULL;
84 char *server_expect = NULL;
85 int smtp_use_dummycmd = 1;
86 char *mail_command = "MAIL ";
87 char *from_arg = " ";
88 int warning_time = 0;
89 int check_warning_time = FALSE;
90 int critical_time = 0;
91 int check_critical_time = FALSE;
92 int verbose = 0;
94 int
95 main (int argc, char **argv)
96 {
97 int sd;
98 double elapsed_time;
99 int result = STATE_UNKNOWN;
100 char buffer[MAX_INPUT_BUFFER] = "";
101 char *from_str = NULL;
102 char *helocmd = NULL;
103 struct timeval tv;
105 if (process_arguments (argc, argv) != OK)
106 usage ("Invalid command arguments supplied\n");
108 /* initialize the HELO command with the localhostname */
109 #ifndef HOST_MAX_BYTES
110 #define HOST_MAX_BYTES 255
111 #endif
112 helocmd = malloc (HOST_MAX_BYTES);
113 gethostname(helocmd, HOST_MAX_BYTES);
114 asprintf (&helocmd, "%s%s%s", SMTP_HELO, helocmd, "\r\n");
116 /* initialize the MAIL command with optional FROM command */
117 asprintf (&from_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
119 if (verbose)
120 printf ("FROMCMD: %s\n", from_str);
122 /* initialize alarm signal handling */
123 (void) signal (SIGALRM, socket_timeout_alarm_handler);
125 /* set socket timeout */
126 (void) alarm (socket_timeout);
128 /* start timer */
129 gettimeofday (&tv, NULL);
131 /* try to connect to the host at the given port number */
132 result = my_tcp_connect (server_address, server_port, &sd);
134 /* we connected, so close connection before exiting */
135 if (result == STATE_OK) {
137 /* watch for the SMTP connection string and */
138 /* return a WARNING status if we couldn't read any data */
139 if (recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0) == -1) {
140 printf ("recv() failed\n");
141 result = STATE_WARNING;
142 }
143 else {
144 /* strip the buffer of carriage returns */
145 strip (buffer);
146 /* make sure we find the response we are looking for */
147 if (!strstr (buffer, server_expect)) {
148 if (server_port == SMTP_PORT)
149 printf ("Invalid SMTP response received from host\n");
150 else
151 printf ("Invalid SMTP response received from host on port %d\n",
152 server_port);
153 result = STATE_WARNING;
154 }
155 }
157 /* send the HELO command */
158 send(sd, helocmd, strlen(helocmd), 0);
160 /* allow for response to helo command to reach us */
161 recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
163 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
164 * to do something useful. This can be prevented by giving a command
165 * even if syntax is illegal (MAIL requires a FROM:<...> argument)
166 *
167 * According to rfc821 you can include a null reversepath in the from command
168 * - but a log message is generated on the smtp server.
169 *
170 * You can disable sending mail_command with '--nocommand'
171 * Use the -f option to provide a FROM address
172 */
173 if (smtp_use_dummycmd) {
175 send(sd, from_str, strlen(from_str), 0);
177 /* allow for response to mail_command to reach us */
178 recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
180 if (verbose)
181 printf("DUMMYCMD: %s\n%s\n",from_str,buffer);
183 } /* smtp_use_dummycmd */
185 /* tell the server we're done */
186 send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
188 /* finally close the connection */
189 close (sd);
190 }
192 /* reset the alarm */
193 alarm (0);
195 elapsed_time = delta_time (tv);
197 if (check_critical_time && elapsed_time > (double) critical_time)
198 result = STATE_CRITICAL;
199 else if (check_warning_time && elapsed_time > (double) warning_time)
200 result = STATE_WARNING;
202 if (verbose)
203 printf ("SMTP %s - %.3f sec. response time, %s|time=%.3f\n",
204 state_text (result), elapsed_time, buffer, elapsed_time);
205 else
206 printf ("SMTP %s - %.3f second response time|time=%.3f\n",
207 state_text (result), elapsed_time, elapsed_time);
209 return result;
210 }
217 /* process command-line arguments */
218 int
219 process_arguments (int argc, char **argv)
220 {
221 int c;
223 int option_index = 0;
224 static struct option long_options[] = {
225 {"hostname", required_argument, 0, 'H'},
226 {"expect", required_argument, 0, 'e'},
227 {"critical", required_argument, 0, 'c'},
228 {"warning", required_argument, 0, 'w'},
229 {"timeout", required_argument, 0, 't'},
230 {"port", required_argument, 0, 'p'},
231 {"from", required_argument, 0, 'f'},
232 {"command", required_argument, 0, 'C'},
233 {"nocommand", required_argument, 0, 'n'},
234 {"verbose", no_argument, 0, 'v'},
235 {"version", no_argument, 0, 'V'},
236 {"help", no_argument, 0, 'h'},
237 {0, 0, 0, 0}
238 };
240 if (argc < 2)
241 return ERROR;
243 for (c = 1; c < argc; c++) {
244 if (strcmp ("-to", argv[c]) == 0)
245 strcpy (argv[c], "-t");
246 else if (strcmp ("-wt", argv[c]) == 0)
247 strcpy (argv[c], "-w");
248 else if (strcmp ("-ct", argv[c]) == 0)
249 strcpy (argv[c], "-c");
250 }
252 while (1) {
253 c = getopt_long (argc, argv, "+hVvt:p:f:e:c:w:H:C:",
254 long_options, &option_index);
256 if (c == -1 || c == EOF)
257 break;
259 switch (c) {
260 case 'H': /* hostname */
261 if (is_host (optarg)) {
262 server_address = optarg;
263 }
264 else {
265 usage ("Invalid host name\n");
266 }
267 break;
268 case 'p': /* port */
269 if (is_intpos (optarg)) {
270 server_port = atoi (optarg);
271 }
272 else {
273 usage ("Server port must be a positive integer\n");
274 }
275 break;
276 case 'f': /* from argument */
277 from_arg = optarg;
278 break;
279 case 'e': /* server expect string on 220 */
280 server_expect = optarg;
281 break;
282 case 'C': /* server expect string on 220 */
283 mail_command = optarg;
284 smtp_use_dummycmd = 1;
285 break;
286 case 'n': /* server expect string on 220 */
287 smtp_use_dummycmd = 0;
288 break;
289 case 'c': /* critical time threshold */
290 if (is_intnonneg (optarg)) {
291 critical_time = atoi (optarg);
292 check_critical_time = TRUE;
293 }
294 else {
295 usage ("Critical time must be a nonnegative integer\n");
296 }
297 break;
298 case 'w': /* warning time threshold */
299 if (is_intnonneg (optarg)) {
300 warning_time = atoi (optarg);
301 check_warning_time = TRUE;
302 }
303 else {
304 usage ("Warning time must be a nonnegative integer\n");
305 }
306 break;
307 case 'v': /* verbose */
308 verbose++;
309 break;
310 case 't': /* timeout */
311 if (is_intnonneg (optarg)) {
312 socket_timeout = atoi (optarg);
313 }
314 else {
315 usage ("Time interval must be a nonnegative integer\n");
316 }
317 break;
318 case 'V': /* version */
319 print_revision (progname, revision);
320 exit (STATE_OK);
321 case 'h': /* help */
322 print_help ();
323 exit (STATE_OK);
324 case '?': /* help */
325 usage ("Invalid argument\n");
326 }
327 }
329 c = optind;
330 if (server_address == NULL) {
331 if (argv[c]) {
332 if (is_host (argv[c]))
333 server_address = argv[c];
334 else
335 usage ("Invalid host name");
336 }
337 else {
338 asprintf (&server_address, "127.0.0.1");
339 }
340 }
342 if (server_expect == NULL)
343 asprintf (&server_expect, SMTP_EXPECT);
345 return validate_arguments ();
346 }
352 int
353 validate_arguments (void)
354 {
355 return OK;
356 }
362 void
363 print_help (void)
364 {
365 print_revision (progname, revision);
366 printf ("Copyright (c) %s %s\n\t<%s>\n\n%s\n",
367 copyright, authors, email, summary);
368 print_usage ();
369 printf ("\nOptions:\n");
370 printf (options, SMTP_PORT, SMTP_EXPECT, mail_command, from_arg,
371 DEFAULT_SOCKET_TIMEOUT);
372 support ();
373 }
379 void
380 print_usage (void)
381 {
382 printf ("Usage: %s %s\n"
383 " %s --help\n"
384 " %s --version\n",
385 progname, option_summary, progname, progname);
386 }