plugins/check_smtp.c

   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 ******************************************************************************/
  18
  19 const char *progname = "check_smtp";
  20 const char *revision = "$Revision$";
  21 const char *copyright = "2000-2003";
  22 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  23
  24 #include "common.h"
  25 #include "netutils.h"
  26 #include "utils.h"
  27
  28 enum {
  29         SMTP_PORT       = 25
  30 };
  31 const char *SMTP_EXPECT = "220";
  32 const char *SMTP_HELO = "HELO ";
  33 const char *SMTP_QUIT   = "QUIT\r\n";
  34
  35 int process_arguments (int, char **);
  36 int validate_arguments (void);
  37 void print_help (void);
  38 void print_usage (void);
  39
  40 int server_port = SMTP_PORT;
  41 char *server_address = NULL;
  42 char *server_expect = NULL;
  43 int smtp_use_dummycmd = 1;
  44 char *mail_command;
  45 char *from_arg;
  46 int warning_time = 0;
  47 int check_warning_time = FALSE;
  48 int critical_time = 0;
  49 int check_critical_time = FALSE;
  50 int verbose = 0;
  51
  52
  53
  54
  55
  56 \f
  57 int
  58 main (int argc, char **argv)
  59 {
  60         int sd;
  61         double elapsed_time;
  62         long microsec;
  63         int result = STATE_UNKNOWN;
  64         char buffer[MAX_INPUT_BUFFER];
  65         char *from_str = NULL;
  66         char *helocmd = NULL;
  67         struct timeval tv;
  68
  69         setlocale (LC_ALL, "");
  70         bindtextdomain (PACKAGE, LOCALEDIR);
  71         textdomain (PACKAGE);
  72
  73         if (process_arguments (argc, argv) != OK)
  74                 usage (_("Invalid command arguments supplied\n"));
  75
  76         /* initialize the HELO command with the localhostname */
  77 #ifndef HOST_MAX_BYTES
  78 #define HOST_MAX_BYTES 255
  79 #endif
  80         helocmd = malloc (HOST_MAX_BYTES);
  81         gethostname(helocmd, HOST_MAX_BYTES);
  82         asprintf (&helocmd, "%s%s%s", SMTP_HELO, helocmd, "\r\n");
  83
  84         /* initialize the MAIL command with optional FROM command  */
  85         asprintf (&from_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
  86
  87         if (verbose)
  88                 printf ("FROMCMD: %s\n", from_str);
  89
  90         /* initialize alarm signal handling */
  91         (void) signal (SIGALRM, socket_timeout_alarm_handler);
  92
  93         /* set socket timeout */
  94         (void) alarm (socket_timeout);
  95
  96         /* start timer */
  97         gettimeofday (&tv, NULL);
  98
  99         /* try to connect to the host at the given port number */
 100         result = my_tcp_connect (server_address, server_port, &sd);
 101
 102         /* we connected, so close connection before exiting */
 103         if (result == STATE_OK) {
 104
 105                 /* watch for the SMTP connection string and */
 106                 /* return a WARNING status if we couldn't read any data */
 107                 if (recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0) == -1) {
 108                         printf (_("recv() failed\n"));
 109                         result = STATE_WARNING;
 110                 }
 111                 else {
 112                         /* strip the buffer of carriage returns */
 113                         strip (buffer);
 114                         /* make sure we find the response we are looking for */
 115                         if (!strstr (buffer, server_expect)) {
 116                                 if (server_port == SMTP_PORT)
 117                                         printf (_("Invalid SMTP response received from host\n"));
 118                                 else
 119                                         printf (_("Invalid SMTP response received from host on port %d\n"),
 120                                                                         server_port);
 121                                 result = STATE_WARNING;
 122                         }
 123                 }
 124
 125                 /* send the HELO command */
 126                 send(sd, helocmd, strlen(helocmd), 0);
 127
 128                 /* allow for response to helo command to reach us */
 129                 recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 130
 131                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 132                  * to do something useful. This can be prevented by giving a command
 133                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 134                  *
 135                  * According to rfc821 you can include a null reversepath in the from command
 136                  * - but a log message is generated on the smtp server.
 137                  *
 138                  * You can disable sending mail_command with '--nocommand'
 139                  * Use the -f option to provide a FROM address
 140                  */
 141                 if (smtp_use_dummycmd) {
 142
 143                         send(sd, from_str, strlen(from_str), 0);
 144
 145                         /* allow for response to mail_command to reach us */
 146                         recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 147
 148                         if (verbose)
 149                                 printf(_("DUMMYCMD: %s\n%s\n"),from_str,buffer);
 150
 151                 } /* smtp_use_dummycmd */
 152
 153                 /* tell the server we're done */
 154                 send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
 155
 156                 /* finally close the connection */
 157                 close (sd);
 158         }
 159
 160         /* reset the alarm */
 161         alarm (0);
 162
 163         microsec = deltime (tv);
 164         elapsed_time = (double)microsec / 1.0e6;
 165
 166         if (check_critical_time && elapsed_time > (double) critical_time)
 167                 result = STATE_CRITICAL;
 168         else if (check_warning_time && elapsed_time > (double) warning_time)
 169                 result = STATE_WARNING;
 170
 171         if (verbose)
 172                 printf (_("SMTP %s - %.3f sec. response time, %s|time=%ldus\n"),
 173                         state_text (result), elapsed_time, buffer, microsec);
 174         else
 175                 printf (_("SMTP %s - %.3f second response time|time=%ldus\n"),
 176                         state_text (result), elapsed_time, microsec);
 177
 178         return result;
 179 }
 180
 181
 182
 183
 184
 185 \f
 186 /* process command-line arguments */
 187 int
 188 process_arguments (int argc, char **argv)
 189 {
 190         int c;
 191
 192         int option = 0;
 193         static struct option longopts[] = {
 194                 {"hostname", required_argument, 0, 'H'},
 195                 {"expect", required_argument, 0, 'e'},
 196                 {"critical", required_argument, 0, 'c'},
 197                 {"warning", required_argument, 0, 'w'},
 198                 {"timeout", required_argument, 0, 't'},
 199                 {"port", required_argument, 0, 'p'},
 200                 {"from", required_argument, 0, 'f'},
 201                 {"command", required_argument, 0, 'C'},
 202                 {"nocommand", required_argument, 0, 'n'},
 203                 {"verbose", no_argument, 0, 'v'},
 204                 {"version", no_argument, 0, 'V'},
 205                 {"use-ipv4", no_argument, 0, '4'},
 206                 {"use-ipv6", no_argument, 0, '6'},
 207                 {"help", no_argument, 0, 'h'},
 208                 {0, 0, 0, 0}
 209         };
 210
 211         if (argc < 2)
 212                 return ERROR;
 213
 214         for (c = 1; c < argc; c++) {
 215                 if (strcmp ("-to", argv[c]) == 0)
 216                         strcpy (argv[c], "-t");
 217                 else if (strcmp ("-wt", argv[c]) == 0)
 218                         strcpy (argv[c], "-w");
 219                 else if (strcmp ("-ct", argv[c]) == 0)
 220                         strcpy (argv[c], "-c");
 221         }
 222
 223         while (1) {
 224                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:",
 225                                  longopts, &option);
 226
 227                 if (c == -1 || c == EOF)
 228                         break;
 229
 230                 switch (c) {
 231                 case 'H':                                                                       /* hostname */
 232                         if (is_host (optarg)) {
 233                                 server_address = optarg;
 234                         }
 235                         else {
 236                                 usage (_("Invalid host name\n"));
 237                         }
 238                         break;
 239                 case 'p':                                                                       /* port */
 240                         if (is_intpos (optarg))
 241                                 server_port = atoi (optarg);
 242                         else
 243                                 usage (_("Server port must be a positive integer\n"));
 244                         break;
 245                 case 'f':                                                                       /* from argument */
 246                         from_arg = optarg;
 247                         break;
 248                 case 'e':                                                                       /* server expect string on 220  */
 249                         server_expect = optarg;
 250                         break;
 251                 case 'C':                                                                       /* server expect string on 220  */
 252                         mail_command = optarg;
 253                         smtp_use_dummycmd = 1;
 254                         break;
 255                 case 'n':                                                                       /* server expect string on 220  */
 256                         smtp_use_dummycmd = 0;
 257                         break;
 258                 case 'c':                                                                       /* critical time threshold */
 259                         if (is_intnonneg (optarg)) {
 260                                 critical_time = atoi (optarg);
 261                                 check_critical_time = TRUE;
 262                         }
 263                         else {
 264                                 usage (_("Critical time must be a nonnegative integer\n"));
 265                         }
 266                         break;
 267                 case 'w':                                                                       /* warning time threshold */
 268                         if (is_intnonneg (optarg)) {
 269                                 warning_time = atoi (optarg);
 270                                 check_warning_time = TRUE;
 271                         }
 272                         else {
 273                                 usage (_("Warning time must be a nonnegative integer\n"));
 274                         }
 275                         break;
 276                 case 'v':                                                                       /* verbose */
 277                         verbose++;
 278                         break;
 279                 case 't':                                                                       /* timeout */
 280                         if (is_intnonneg (optarg)) {
 281                                 socket_timeout = atoi (optarg);
 282                         }
 283                         else {
 284                                 usage (_("Time interval must be a nonnegative integer\n"));
 285                         }
 286                         break;
 287                 case '4':
 288                         address_family = AF_INET;
 289                         break;
 290                 case '6':
 291 #ifdef USE_IPV6
 292                         address_family = AF_INET6;
 293 #else
 294                         usage (_("IPv6 support not available\n"));
 295 #endif
 296                         break;
 297                 case 'V':                                                                       /* version */
 298                         print_revision (progname, revision);
 299                         exit (STATE_OK);
 300                 case 'h':                                                                       /* help */
 301                         print_help ();
 302                         exit (STATE_OK);
 303                 case '?':                                                                       /* help */
 304                         usage (_("Invalid argument\n"));
 305                 }
 306         }
 307
 308         c = optind;
 309         if (server_address == NULL) {
 310                 if (argv[c]) {
 311                         if (is_host (argv[c]))
 312                                 server_address = argv[c];
 313                         else
 314                                 usage (_("Invalid host name"));
 315                 }
 316                 else {
 317                         asprintf (&server_address, "127.0.0.1");
 318                 }
 319         }
 320
 321         if (server_expect == NULL)
 322                 server_expect = strdup (SMTP_EXPECT);
 323
 324         if (mail_command == NULL)
 325                 mail_command = strdup("MAIL ");
 326
 327         if (from_arg==NULL)
 328                 from_arg = strdup(" ");
 329
 330         return validate_arguments ();
 331 }
 332
 333
 334
 335
 336
 337 int
 338 validate_arguments (void)
 339 {
 340         return OK;
 341 }
 342
 343
 344
 345
 346
 347 \f
 348 void
 349 print_help (void)
 350 {
 351         char *myport;
 352         asprintf (&myport, "%d", SMTP_PORT);
 353
 354         print_revision (progname, revision);
 355
 356         printf (_("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n"));
 357         printf (_(COPYRIGHT), copyright, email);
 358
 359         printf(_("\
 360 This plugin will attempt to open an SMTP connection with the host.\n\n"));
 361
 362         print_usage ();
 363
 364         printf (_(UT_HELP_VRSN));
 365
 366         printf (_(UT_HOST_PORT), 'p', myport);
 367
 368         printf (_(UT_IPv46));
 369
 370         printf (_("\
 371  -e, --expect=STRING\n\
 372    String to expect in first line of server response (default: '%s')\n\
 373  -n, nocommand\n\
 374    Suppress SMTP command\n\
 375  -C, --command=STRING\n\
 376    SMTP command (default: '%s')\n\
 377  -f, --from=STRING\n\
 378    FROM-address to include in MAIL command, required by Exchange 2000\n\
 379    (default: '%s')\n"), SMTP_EXPECT, mail_command, from_arg);
 380
 381         printf (_(UT_WARN_CRIT));
 382
 383         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 384
 385         printf (_(UT_VERBOSE));
 386
 387         printf(_("\n\
 388 Successul connects return STATE_OK, refusals and timeouts return\n\
 389 STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful\n\
 390 connects, but incorrect reponse messages from the host result in\n\
 391 STATE_WARNING return values.\n"));
 392
 393         printf (_(UT_SUPPORT));
 394 }
 395
 396
 397
 398
 399
 400 void
 401 print_usage (void)
 402 {
 403         printf ("\
 404 Usage: %s -H host [-p port] [-e expect] [-C command] [-f from addr]\n\
 405   [-w warn] [-c crit] [-t timeout] [-n] [-v] [-4|-6]\n", progname);
 406         printf (_(UT_HLP_VRS), progname, progname);
 407 }
 408
 409
 410