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 #ifdef HAVE_REGEX_H
  41 #include <regex.h>
  42 char regex_expect[MAX_INPUT_BUFFER] = "";
  43 regex_t preg;
  44 regmatch_t pmatch[10];
  45 char timestamp[10] = "";
  46 char errbuf[MAX_INPUT_BUFFER];
  47 int cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
  48 int eflags = 0;
  49 int errcode, excode;
  50 #endif
  51
  52 int server_port = SMTP_PORT;
  53 char *server_address = NULL;
  54 char *server_expect = NULL;
  55 int smtp_use_dummycmd = 0;
  56 char *mail_command = NULL;
  57 char *from_arg = NULL;
  58 int ncommands=0;
  59 int command_size=0;
  60 int nresponses=0;
  61 int response_size=0;
  62 char **commands = NULL;
  63 char **responses = NULL;
  64 int warning_time = 0;
  65 int check_warning_time = FALSE;
  66 int critical_time = 0;
  67 int check_critical_time = FALSE;
  68 int verbose = 0;
  69
  70
  71
  72
  73
  74 \f
  75 int
  76 main (int argc, char **argv)
  77 {
  78         int sd;
  79         int n = 0;
  80         double elapsed_time;
  81         long microsec;
  82         int result = STATE_UNKNOWN;
  83         char buffer[MAX_INPUT_BUFFER];
  84         char *cmd_str = NULL;
  85         char *helocmd = NULL;
  86         struct timeval tv;
  87
  88         setlocale (LC_ALL, "");
  89         bindtextdomain (PACKAGE, LOCALEDIR);
  90         textdomain (PACKAGE);
  91
  92         if (process_arguments (argc, argv) != OK)
  93                 usage (_("Invalid command arguments supplied\n"));
  94
  95         /* initialize the HELO command with the localhostname */
  96 #ifndef HOST_MAX_BYTES
  97 #define HOST_MAX_BYTES 255
  98 #endif
  99         helocmd = malloc (HOST_MAX_BYTES);
 100         gethostname(helocmd, HOST_MAX_BYTES);
 101         asprintf (&helocmd, "%s%s%s", SMTP_HELO, helocmd, "\r\n");
 102
 103         /* initialize the MAIL command with optional FROM command  */
 104         asprintf (&cmd_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
 105
 106         if (verbose && smtp_use_dummycmd)
 107                 printf ("FROM CMD: %s", cmd_str);
 108
 109         /* initialize alarm signal handling */
 110         (void) signal (SIGALRM, socket_timeout_alarm_handler);
 111
 112         /* set socket timeout */
 113         (void) alarm (socket_timeout);
 114
 115         /* start timer */
 116         gettimeofday (&tv, NULL);
 117
 118         /* try to connect to the host at the given port number */
 119         result = my_tcp_connect (server_address, server_port, &sd);
 120
 121         if (result == STATE_OK) { /* we connected */
 122
 123                 /* watch for the SMTP connection string and */
 124                 /* return a WARNING status if we couldn't read any data */
 125                 if (recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0) == -1) {
 126                         printf (_("recv() failed\n"));
 127                         result = STATE_WARNING;
 128                 }
 129                 else {
 130                         if (verbose)
 131                                 printf ("%s", buffer);
 132                         /* strip the buffer of carriage returns */
 133                         strip (buffer);
 134                         /* make sure we find the response we are looking for */
 135                         if (!strstr (buffer, server_expect)) {
 136                                 if (server_port == SMTP_PORT)
 137                                         printf (_("Invalid SMTP response received from host\n"));
 138                                 else
 139                                         printf (_("Invalid SMTP response received from host on port %d\n"),
 140                                                                         server_port);
 141                                 result = STATE_WARNING;
 142                         }
 143                 }
 144
 145                 /* send the HELO command */
 146                 send(sd, helocmd, strlen(helocmd), 0);
 147
 148                 /* allow for response to helo command to reach us */
 149                 recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 150
 151                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 152                  * to do something useful. This can be prevented by giving a command
 153                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 154                  *
 155                  * According to rfc821 you can include a null reversepath in the from command
 156                  * - but a log message is generated on the smtp server.
 157                  *
 158                  * You can disable sending mail_command with '--nocommand'
 159                  * Use the -f option to provide a FROM address
 160                  */
 161                 if (smtp_use_dummycmd) {
 162                         send(sd, cmd_str, strlen(cmd_str), 0);
 163                         recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 164                         if (verbose)
 165                                 printf("%s", buffer);
 166                 }
 167
 168                 while (n < ncommands) {
 169                         asprintf (&cmd_str, "%s%s", commands[n], "\r\n");
 170                         send(sd, cmd_str, strlen(cmd_str), 0);
 171                         recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 172                         if (verbose)
 173                                 printf("%s", buffer);
 174                         strip (buffer);
 175                         if (n < nresponses) {
 176 #ifdef HAVE_REGEX_H
 177                                 cflags |= REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
 178                                 //strncpy (regex_expect, responses[n], sizeof (regex_expect) - 1);
 179                                 //regex_expect[sizeof (regex_expect) - 1] = '\0';
 180                                 errcode = regcomp (&preg, responses[n], cflags);
 181                                 if (errcode != 0) {
 182                                         regerror (errcode, &preg, errbuf, MAX_INPUT_BUFFER);
 183                                         printf (_("Could Not Compile Regular Expression"));
 184                                         return ERROR;
 185                                 }
 186                                 excode = regexec (&preg, buffer, 10, pmatch, eflags);
 187                                 if (excode == 0) {
 188                                         result = STATE_OK;
 189                                 }
 190                                 else if (excode == REG_NOMATCH) {
 191                                         result = STATE_WARNING;
 192                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 193                                 }
 194                                 else {
 195                                         regerror (excode, &preg, errbuf, MAX_INPUT_BUFFER);
 196                                         printf (_("Execute Error: %s\n"), errbuf);
 197                                         result = STATE_UNKNOWN;
 198                                 }
 199 #else
 200                                 if (strstr(buffer, responses[n])!=buffer) {
 201                                         result = STATE_WARNING;
 202                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 203                                 }
 204 #endif
 205                         }
 206                         n++;
 207                 }
 208
 209                 /* tell the server we're done */
 210                 send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
 211
 212                 /* finally close the connection */
 213                 close (sd);
 214         }
 215
 216         /* reset the alarm */
 217         alarm (0);
 218
 219         microsec = deltime (tv);
 220         elapsed_time = (double)microsec / 1.0e6;
 221
 222         if (check_critical_time && elapsed_time > (double) critical_time)
 223                 result = STATE_CRITICAL;
 224         else if (check_warning_time && elapsed_time > (double) warning_time)
 225                 result = STATE_WARNING;
 226
 227         printf (_("SMTP %s - %.3f sec. response time%s%s|%s\n"),
 228                 state_text (result), elapsed_time,
 229           verbose?", ":"", verbose?buffer:"",
 230                 perfdata ("time", microsec, "us",
 231                           check_warning_time, (long)(1000000*warning_time),
 232                           check_critical_time, (long)(1000000*critical_time),
 233                           TRUE, 0, FALSE, 0));
 234
 235         return result;
 236 }
 237
 238
 239
 240
 241
 242 \f
 243 /* process command-line arguments */
 244 int
 245 process_arguments (int argc, char **argv)
 246 {
 247         int c;
 248
 249         int option = 0;
 250         static struct option longopts[] = {
 251                 {"hostname", required_argument, 0, 'H'},
 252                 {"expect", required_argument, 0, 'e'},
 253                 {"critical", required_argument, 0, 'c'},
 254                 {"warning", required_argument, 0, 'w'},
 255                 {"timeout", required_argument, 0, 't'},
 256                 {"port", required_argument, 0, 'p'},
 257                 {"from", required_argument, 0, 'f'},
 258                 {"command", required_argument, 0, 'C'},
 259                 {"response", required_argument, 0, 'R'},
 260                 {"nocommand", required_argument, 0, 'n'},
 261                 {"verbose", no_argument, 0, 'v'},
 262                 {"version", no_argument, 0, 'V'},
 263                 {"use-ipv4", no_argument, 0, '4'},
 264                 {"use-ipv6", no_argument, 0, '6'},
 265                 {"help", no_argument, 0, 'h'},
 266                 {0, 0, 0, 0}
 267         };
 268
 269         if (argc < 2)
 270                 return ERROR;
 271
 272         for (c = 1; c < argc; c++) {
 273                 if (strcmp ("-to", argv[c]) == 0)
 274                         strcpy (argv[c], "-t");
 275                 else if (strcmp ("-wt", argv[c]) == 0)
 276                         strcpy (argv[c], "-w");
 277                 else if (strcmp ("-ct", argv[c]) == 0)
 278                         strcpy (argv[c], "-c");
 279         }
 280
 281         while (1) {
 282                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:",
 283                                  longopts, &option);
 284
 285                 if (c == -1 || c == EOF)
 286                         break;
 287
 288                 switch (c) {
 289                 case 'H':                                                                       /* hostname */
 290                         if (is_host (optarg)) {
 291                                 server_address = optarg;
 292                         }
 293                         else {
 294                                 usage (_("Invalid host name\n"));
 295                         }
 296                         break;
 297                 case 'p':                                                                       /* port */
 298                         if (is_intpos (optarg))
 299                                 server_port = atoi (optarg);
 300                         else
 301                                 usage (_("Server port must be a positive integer\n"));
 302                         break;
 303                 case 'f':                                                                       /* from argument */
 304                         from_arg = optarg;
 305                         smtp_use_dummycmd = 1;
 306                         break;
 307                 case 'e':                                                                       /* server expect string on 220  */
 308                         server_expect = optarg;
 309                         break;
 310                 case 'C':                                                                       /* commands  */
 311                         if (ncommands >= command_size) {
 312                                 commands = realloc (commands, command_size+8);
 313                                 if (commands == NULL)
 314                                         die (STATE_UNKNOWN,
 315                                              _("Could not realloc() units [%d]\n"), ncommands);
 316                         }
 317                         commands[ncommands] = optarg;
 318                         ncommands++;
 319                         break;
 320                 case 'R':                                                                       /* server responses */
 321                         if (nresponses >= response_size) {
 322                                 responses = realloc (responses, response_size+8);
 323                                 if (responses == NULL)
 324                                         die (STATE_UNKNOWN,
 325                                              _("Could not realloc() units [%d]\n"), nresponses);
 326                         }
 327                         responses[nresponses] = optarg;
 328                         nresponses++;
 329                         break;
 330                 case 'c':                                                                       /* critical time threshold */
 331                         if (is_intnonneg (optarg)) {
 332                                 critical_time = atoi (optarg);
 333                                 check_critical_time = TRUE;
 334                         }
 335                         else {
 336                                 usage (_("Critical time must be a nonnegative integer\n"));
 337                         }
 338                         break;
 339                 case 'w':                                                                       /* warning time threshold */
 340                         if (is_intnonneg (optarg)) {
 341                                 warning_time = atoi (optarg);
 342                                 check_warning_time = TRUE;
 343                         }
 344                         else {
 345                                 usage (_("Warning time must be a nonnegative integer\n"));
 346                         }
 347                         break;
 348                 case 'v':                                                                       /* verbose */
 349                         verbose++;
 350                         break;
 351                 case 't':                                                                       /* timeout */
 352                         if (is_intnonneg (optarg)) {
 353                                 socket_timeout = atoi (optarg);
 354                         }
 355                         else {
 356                                 usage (_("Time interval must be a nonnegative integer\n"));
 357                         }
 358                         break;
 359                 case '4':
 360                         address_family = AF_INET;
 361                         break;
 362                 case '6':
 363 #ifdef USE_IPV6
 364                         address_family = AF_INET6;
 365 #else
 366                         usage (_("IPv6 support not available\n"));
 367 #endif
 368                         break;
 369                 case 'V':                                                                       /* version */
 370                         print_revision (progname, revision);
 371                         exit (STATE_OK);
 372                 case 'h':                                                                       /* help */
 373                         print_help ();
 374                         exit (STATE_OK);
 375                 case '?':                                                                       /* help */
 376                         usage (_("Invalid argument\n"));
 377                 }
 378         }
 379
 380         c = optind;
 381         if (server_address == NULL) {
 382                 if (argv[c]) {
 383                         if (is_host (argv[c]))
 384                                 server_address = argv[c];
 385                         else
 386                                 usage (_("Invalid host name"));
 387                 }
 388                 else {
 389                         asprintf (&server_address, "127.0.0.1");
 390                 }
 391         }
 392
 393         if (server_expect == NULL)
 394                 server_expect = strdup (SMTP_EXPECT);
 395
 396         if (mail_command == NULL)
 397                 mail_command = strdup("MAIL ");
 398
 399         if (from_arg==NULL)
 400                 from_arg = strdup(" ");
 401
 402         return validate_arguments ();
 403 }
 404
 405
 406
 407
 408
 409 int
 410 validate_arguments (void)
 411 {
 412         return OK;
 413 }
 414
 415
 416
 417
 418
 419 \f
 420 void
 421 print_help (void)
 422 {
 423         char *myport;
 424         asprintf (&myport, "%d", SMTP_PORT);
 425
 426         print_revision (progname, revision);
 427
 428         printf (_("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n"));
 429         printf (_(COPYRIGHT), copyright, email);
 430
 431         printf(_("\
 432 This plugin will attempt to open an SMTP connection with the host.\n\n"));
 433
 434         print_usage ();
 435
 436         printf (_(UT_HELP_VRSN));
 437
 438         printf (_(UT_HOST_PORT), 'p', myport);
 439
 440         printf (_(UT_IPv46));
 441
 442         printf (_("\
 443  -e, --expect=STRING\n\
 444    String to expect in first line of server response (default: '%s')\n\
 445  -n, nocommand\n\
 446    Suppress SMTP command\n\
 447  -C, --command=STRING\n\
 448    SMTP command (may be used repeatedly)\n\
 449  -R, --command=STRING\n\
 450    Expected response to command (may be used repeatedly)\n\
 451  -f, --from=STRING\n\
 452    FROM-address to include in MAIL command, required by Exchange 2000\n"),
 453                 SMTP_EXPECT);
 454
 455         printf (_(UT_WARN_CRIT));
 456
 457         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 458
 459         printf (_(UT_VERBOSE));
 460
 461         printf(_("\n\
 462 Successul connects return STATE_OK, refusals and timeouts return\n\
 463 STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful\n\
 464 connects, but incorrect reponse messages from the host result in\n\
 465 STATE_WARNING return values.\n"));
 466
 467         printf (_(UT_SUPPORT));
 468 }
 469
 470
 471
 472
 473
 474 void
 475 print_usage (void)
 476 {
 477         printf ("\
 478 Usage: %s -H host [-p port] [-e expect] [-C command] [-f from addr]\n\
 479   [-w warn] [-c crit] [-t timeout] [-n] [-v] [-4|-6]\n", progname);
 480         printf (_(UT_HLP_VRS), progname, progname);
 481 }
 482
 483
 484