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  $Id$
  18
  19 ******************************************************************************/
  20
  21 const char *progname = "check_smtp";
  22 const char *revision = "$Revision$";
  23 const char *copyright = "2000-2004";
  24 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  25
  26 #include "common.h"
  27 #include "netutils.h"
  28 #include "utils.h"
  29
  30 enum {
  31         SMTP_PORT       = 25
  32 };
  33 const char *SMTP_EXPECT = "220";
  34 const char *SMTP_HELO = "HELO ";
  35 const char *SMTP_QUIT   = "QUIT\r\n";
  36
  37 int process_arguments (int, char **);
  38 int validate_arguments (void);
  39 void print_help (void);
  40 void print_usage (void);
  41
  42 #ifdef HAVE_REGEX_H
  43 #include <regex.h>
  44 char regex_expect[MAX_INPUT_BUFFER] = "";
  45 regex_t preg;
  46 regmatch_t pmatch[10];
  47 char timestamp[10] = "";
  48 char errbuf[MAX_INPUT_BUFFER];
  49 int cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
  50 int eflags = 0;
  51 int errcode, excode;
  52 #endif
  53
  54 int server_port = SMTP_PORT;
  55 char *server_address = NULL;
  56 char *server_expect = NULL;
  57 int smtp_use_dummycmd = 0;
  58 char *mail_command = NULL;
  59 char *from_arg = NULL;
  60 int ncommands=0;
  61 int command_size=0;
  62 int nresponses=0;
  63 int response_size=0;
  64 char **commands = NULL;
  65 char **responses = NULL;
  66 int warning_time = 0;
  67 int check_warning_time = FALSE;
  68 int critical_time = 0;
  69 int check_critical_time = FALSE;
  70 int verbose = 0;
  71
  72
  73
  74 int
  75 main (int argc, char **argv)
  76 {
  77         int sd;
  78         int n = 0;
  79         double elapsed_time;
  80         long microsec;
  81         int result = STATE_UNKNOWN;
  82         char buffer[MAX_INPUT_BUFFER];
  83         char *cmd_str = NULL;
  84         char *helocmd = NULL;
  85         struct timeval tv;
  86
  87         setlocale (LC_ALL, "");
  88         bindtextdomain (PACKAGE, LOCALEDIR);
  89         textdomain (PACKAGE);
  90
  91         if (process_arguments (argc, argv) == ERROR)
  92                 usage4 (_("Could not parse arguments"));
  93
  94         /* initialize the HELO command with the localhostname */
  95 #ifndef HOST_MAX_BYTES
  96 #define HOST_MAX_BYTES 255
  97 #endif
  98         helocmd = malloc (HOST_MAX_BYTES);
  99         gethostname(helocmd, HOST_MAX_BYTES);
 100         asprintf (&helocmd, "%s%s%s", SMTP_HELO, helocmd, "\r\n");
 101
 102         /* initialize the MAIL command with optional FROM command  */
 103         asprintf (&cmd_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
 104
 105         if (verbose && smtp_use_dummycmd)
 106                 printf ("FROM CMD: %s", cmd_str);
 107
 108         /* initialize alarm signal handling */
 109         (void) signal (SIGALRM, socket_timeout_alarm_handler);
 110
 111         /* set socket timeout */
 112         (void) alarm (socket_timeout);
 113
 114         /* start timer */
 115         gettimeofday (&tv, NULL);
 116
 117         /* try to connect to the host at the given port number */
 118         result = my_tcp_connect (server_address, server_port, &sd);
 119
 120         if (result == STATE_OK) { /* we connected */
 121
 122                 /* watch for the SMTP connection string and */
 123                 /* return a WARNING status if we couldn't read any data */
 124                 if (recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0) == -1) {
 125                         printf (_("recv() failed\n"));
 126                         result = STATE_WARNING;
 127                 }
 128                 else {
 129                         if (verbose)
 130                                 printf ("%s", buffer);
 131                         /* strip the buffer of carriage returns */
 132                         strip (buffer);
 133                         /* make sure we find the response we are looking for */
 134                         if (!strstr (buffer, server_expect)) {
 135                                 if (server_port == SMTP_PORT)
 136                                         printf (_("Invalid SMTP response received from host\n"));
 137                                 else
 138                                         printf (_("Invalid SMTP response received from host on port %d\n"),
 139                                                                         server_port);
 140                                 result = STATE_WARNING;
 141                         }
 142                 }
 143
 144                 /* send the HELO command */
 145                 send(sd, helocmd, strlen(helocmd), 0);
 146
 147                 /* allow for response to helo command to reach us */
 148                 recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 149
 150                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 151                  * to do something useful. This can be prevented by giving a command
 152                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 153                  *
 154                  * According to rfc821 you can include a null reversepath in the from command
 155                  * - but a log message is generated on the smtp server.
 156                  *
 157                  * You can disable sending mail_command with '--nocommand'
 158                  * Use the -f option to provide a FROM address
 159                  */
 160                 if (smtp_use_dummycmd) {
 161                         send(sd, cmd_str, strlen(cmd_str), 0);
 162                         recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 163                         if (verbose)
 164                                 printf("%s", buffer);
 165                 }
 166
 167                 while (n < ncommands) {
 168                         asprintf (&cmd_str, "%s%s", commands[n], "\r\n");
 169                         send(sd, cmd_str, strlen(cmd_str), 0);
 170                         recv(sd, buffer, MAX_INPUT_BUFFER-1, 0);
 171                         if (verbose)
 172                                 printf("%s", buffer);
 173                         strip (buffer);
 174                         if (n < nresponses) {
 175 #ifdef HAVE_REGEX_H
 176                                 cflags |= REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
 177                                 //strncpy (regex_expect, responses[n], sizeof (regex_expect) - 1);
 178                                 //regex_expect[sizeof (regex_expect) - 1] = '\0';
 179                                 errcode = regcomp (&preg, responses[n], cflags);
 180                                 if (errcode != 0) {
 181                                         regerror (errcode, &preg, errbuf, MAX_INPUT_BUFFER);
 182                                         printf (_("Could Not Compile Regular Expression"));
 183                                         return ERROR;
 184                                 }
 185                                 excode = regexec (&preg, buffer, 10, pmatch, eflags);
 186                                 if (excode == 0) {
 187                                         result = STATE_OK;
 188                                 }
 189                                 else if (excode == REG_NOMATCH) {
 190                                         result = STATE_WARNING;
 191                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 192                                 }
 193                                 else {
 194                                         regerror (excode, &preg, errbuf, MAX_INPUT_BUFFER);
 195                                         printf (_("Execute Error: %s\n"), errbuf);
 196                                         result = STATE_UNKNOWN;
 197                                 }
 198 #else
 199                                 if (strstr(buffer, responses[n])!=buffer) {
 200                                         result = STATE_WARNING;
 201                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 202                                 }
 203 #endif
 204                         }
 205                         n++;
 206                 }
 207
 208                 /* tell the server we're done */
 209                 send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
 210
 211                 /* finally close the connection */
 212                 close (sd);
 213         }
 214
 215         /* reset the alarm */
 216         alarm (0);
 217
 218         microsec = deltime (tv);
 219         elapsed_time = (double)microsec / 1.0e6;
 220
 221         if (result == STATE_OK) {
 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
 228         printf (_("SMTP %s - %.3f sec. response time%s%s|%s\n"),
 229                 state_text (result), elapsed_time,
 230           verbose?", ":"", verbose?buffer:"",
 231                 fperfdata ("time", elapsed_time, "s",
 232                           (int)check_warning_time, warning_time,
 233                           (int)check_critical_time, critical_time,
 234                           TRUE, 0, FALSE, 0));
 235
 236         return result;
 237 }
 238
 239
 240
 241 /* process command-line arguments */
 242 int
 243 process_arguments (int argc, char **argv)
 244 {
 245         int c;
 246
 247         int option = 0;
 248         static struct option longopts[] = {
 249                 {"hostname", required_argument, 0, 'H'},
 250                 {"expect", required_argument, 0, 'e'},
 251                 {"critical", required_argument, 0, 'c'},
 252                 {"warning", required_argument, 0, 'w'},
 253                 {"timeout", required_argument, 0, 't'},
 254                 {"port", required_argument, 0, 'p'},
 255                 {"from", required_argument, 0, 'f'},
 256                 {"command", required_argument, 0, 'C'},
 257                 {"response", required_argument, 0, 'R'},
 258                 {"nocommand", required_argument, 0, 'n'},
 259                 {"verbose", no_argument, 0, 'v'},
 260                 {"version", no_argument, 0, 'V'},
 261                 {"use-ipv4", no_argument, 0, '4'},
 262                 {"use-ipv6", no_argument, 0, '6'},
 263                 {"help", no_argument, 0, 'h'},
 264                 {0, 0, 0, 0}
 265         };
 266
 267         if (argc < 2)
 268                 return ERROR;
 269
 270         for (c = 1; c < argc; c++) {
 271                 if (strcmp ("-to", argv[c]) == 0)
 272                         strcpy (argv[c], "-t");
 273                 else if (strcmp ("-wt", argv[c]) == 0)
 274                         strcpy (argv[c], "-w");
 275                 else if (strcmp ("-ct", argv[c]) == 0)
 276                         strcpy (argv[c], "-c");
 277         }
 278
 279         while (1) {
 280                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:",
 281                                  longopts, &option);
 282
 283                 if (c == -1 || c == EOF)
 284                         break;
 285
 286                 switch (c) {
 287                 case 'H':                                                                       /* hostname */
 288                         if (is_host (optarg)) {
 289                                 server_address = optarg;
 290                         }
 291                         else {
 292                                 usage2 (_("Invalid hostname/address"), optarg);
 293                         }
 294                         break;
 295                 case 'p':                                                                       /* port */
 296                         if (is_intpos (optarg))
 297                                 server_port = atoi (optarg);
 298                         else
 299                                 usage4 (_("Port must be a positive integer"));
 300                         break;
 301                 case 'f':                                                                       /* from argument */
 302                         from_arg = optarg;
 303                         smtp_use_dummycmd = 1;
 304                         break;
 305                 case 'e':                                                                       /* server expect string on 220  */
 306                         server_expect = optarg;
 307                         break;
 308                 case 'C':                                                                       /* commands  */
 309                         if (ncommands >= command_size) {
 310                                 commands = realloc (commands, command_size+8);
 311                                 if (commands == NULL)
 312                                         die (STATE_UNKNOWN,
 313                                              _("Could not realloc() units [%d]\n"), ncommands);
 314                         }
 315                         commands[ncommands] = optarg;
 316                         ncommands++;
 317                         break;
 318                 case 'R':                                                                       /* server responses */
 319                         if (nresponses >= response_size) {
 320                                 responses = realloc (responses, response_size+8);
 321                                 if (responses == NULL)
 322                                         die (STATE_UNKNOWN,
 323                                              _("Could not realloc() units [%d]\n"), nresponses);
 324                         }
 325                         responses[nresponses] = optarg;
 326                         nresponses++;
 327                         break;
 328                 case 'c':                                                                       /* critical time threshold */
 329                         if (is_intnonneg (optarg)) {
 330                                 critical_time = atoi (optarg);
 331                                 check_critical_time = TRUE;
 332                         }
 333                         else {
 334                                 usage4 (_("Critical time must be a positive integer"));
 335                         }
 336                         break;
 337                 case 'w':                                                                       /* warning time threshold */
 338                         if (is_intnonneg (optarg)) {
 339                                 warning_time = atoi (optarg);
 340                                 check_warning_time = TRUE;
 341                         }
 342                         else {
 343                                 usage4 (_("Warning time must be a positive integer"));
 344                         }
 345                         break;
 346                 case 'v':                                                                       /* verbose */
 347                         verbose++;
 348                         break;
 349                 case 't':                                                                       /* timeout */
 350                         if (is_intnonneg (optarg)) {
 351                                 socket_timeout = atoi (optarg);
 352                         }
 353                         else {
 354                                 usage4 (_("Time interval must be a positive integer"));
 355                         }
 356                         break;
 357                 case '4':
 358                         address_family = AF_INET;
 359                         break;
 360                 case '6':
 361 #ifdef USE_IPV6
 362                         address_family = AF_INET6;
 363 #else
 364                         usage4 (_("IPv6 support not available"));
 365 #endif
 366                         break;
 367                 case 'V':                                                                       /* version */
 368                         print_revision (progname, revision);
 369                         exit (STATE_OK);
 370                 case 'h':                                                                       /* help */
 371                         print_help ();
 372                         exit (STATE_OK);
 373                 case '?':                                                                       /* help */
 374                         printf (_("%s: Unknown argument: %s\n\n"), progname, optarg);
 375                         print_usage ();
 376                         exit (STATE_UNKNOWN);
 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                                 usage2 (_("Invalid hostname/address"), argv[c]);
 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 int
 408 validate_arguments (void)
 409 {
 410         return OK;
 411 }
 412
 413
 414
 415 void
 416 print_help (void)
 417 {
 418         char *myport;
 419         asprintf (&myport, "%d", SMTP_PORT);
 420
 421         print_revision (progname, revision);
 422
 423         printf ("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n");
 424         printf (COPYRIGHT, copyright, email);
 425
 426         printf(_("This plugin will attempt to open an SMTP connection with the host.\n\n"));
 427
 428         print_usage ();
 429
 430         printf (_(UT_HELP_VRSN));
 431
 432         printf (_(UT_HOST_PORT), 'p', myport);
 433
 434         printf (_(UT_IPv46));
 435
 436         printf (_("\
 437  -e, --expect=STRING\n\
 438    String to expect in first line of server response (default: '%s')\n\
 439  -n, nocommand\n\
 440    Suppress SMTP command\n\
 441  -C, --command=STRING\n\
 442    SMTP command (may be used repeatedly)\n\
 443  -R, --command=STRING\n\
 444    Expected response to command (may be used repeatedly)\n\
 445  -f, --from=STRING\n\
 446    FROM-address to include in MAIL command, required by Exchange 2000\n"),
 447                 SMTP_EXPECT);
 448
 449         printf (_(UT_WARN_CRIT));
 450
 451         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 452
 453         printf (_(UT_VERBOSE));
 454
 455         printf(_("\n\
 456 Successul connects return STATE_OK, refusals and timeouts return\n\
 457 STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful\n\
 458 connects, but incorrect reponse messages from the host result in\n\
 459 STATE_WARNING return values.\n"));
 460
 461         printf (_(UT_SUPPORT));
 462 }
 463
 464
 465
 466 void
 467 print_usage (void)
 468 {
 469         printf ("\
 470 Usage: %s -H host [-p port] [-e expect] [-C command] [-f from addr]\n\
 471                   [-w warn] [-c crit] [-t timeout] [-n] [-v] [-4|-6]\n", progname);
 472 }