plugins/check_smtp.c

   1 /******************************************************************************
   2 *
   3 * Nagios check_smtp plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 1999-2006 nagios-plugins team
   7 *
   8 * Last Modified: $Date$
   9 *
  10 * Description:
  11 *
  12 * This file contains the check_smtp plugin
  13 *
  14 *  This plugin will attempt to open an SMTP connection with the host.
  15 *
  16 *
  17 * License Information:
  18 *
  19 * This program is free software; you can redistribute it and/or modify
  20 * it under the terms of the GNU General Public License as published by
  21 * the Free Software Foundation; either version 2 of the License, or
  22 * (at your option) any later version.
  23 *
  24 * This program is distributed in the hope that it will be useful,
  25 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27 * GNU General Public License for more details.
  28 *
  29 * You should have received a copy of the GNU General Public License
  30 * along with this program; if not, write to the Free Software
  31 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  32 *
  33 *
  34 * $Id$
  35 *
  36 ******************************************************************************/
  37
  38 const char *progname = "check_smtp";
  39 const char *revision = "$Revision$";
  40 const char *copyright = "2000-2006";
  41 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  42
  43 #include <ctype.h>
  44
  45 #include "common.h"
  46 #include "netutils.h"
  47 #include "utils.h"
  48 #include "base64.h"
  49
  50 #ifdef HAVE_SSL
  51 int check_cert = FALSE;
  52 int days_till_exp;
  53 #  define my_recv(buf, len) ((use_ssl && ssl_established) ? np_net_ssl_read(buf, len) : read(sd, buf, len))
  54 #  define my_send(buf, len) ((use_ssl && ssl_established) ? np_net_ssl_write(buf, len) : send(sd, buf, len, 0))
  55 #else /* ifndef HAVE_SSL */
  56 #  define my_recv(buf, len) read(sd, buf, len)
  57 #  define my_send(buf, len) send(sd, buf, len, 0)
  58 #endif
  59
  60 enum {
  61         SMTP_PORT       = 25
  62 };
  63 #define SMTP_EXPECT "220"
  64 #define SMTP_HELO "HELO "
  65 #define SMTP_EHLO "EHLO "
  66 #define SMTP_QUIT "QUIT\r\n"
  67 #define SMTP_STARTTLS "STARTTLS\r\n"
  68 #define SMTP_AUTH_LOGIN "AUTH LOGIN\r\n"
  69
  70 #ifndef HOST_MAX_BYTES
  71 #define HOST_MAX_BYTES 255
  72 #endif
  73
  74 #define EHLO_SUPPORTS_STARTTLS 1
  75
  76 int process_arguments (int, char **);
  77 int validate_arguments (void);
  78 void print_help (void);
  79 void print_usage (void);
  80 void smtp_quit(void);
  81 int recvline(char *, size_t);
  82 int recvlines(char *, size_t);
  83 int my_close(void);
  84
  85 #include "regex.h"
  86 char regex_expect[MAX_INPUT_BUFFER] = "";
  87 regex_t preg;
  88 regmatch_t pmatch[10];
  89 char timestamp[20] = "";
  90 char errbuf[MAX_INPUT_BUFFER];
  91 int cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
  92 int eflags = 0;
  93 int errcode, excode;
  94
  95 int server_port = SMTP_PORT;
  96 char *server_address = NULL;
  97 char *server_expect = NULL;
  98 int smtp_use_dummycmd = 0;
  99 char *mail_command = NULL;
 100 char *from_arg = NULL;
 101 int ncommands=0;
 102 int command_size=0;
 103 int nresponses=0;
 104 int response_size=0;
 105 char **commands = NULL;
 106 char **responses = NULL;
 107 char *authtype = NULL;
 108 char *authuser = NULL;
 109 char *authpass = NULL;
 110 int warning_time = 0;
 111 int check_warning_time = FALSE;
 112 int critical_time = 0;
 113 int check_critical_time = FALSE;
 114 int verbose = 0;
 115 int use_ssl = FALSE;
 116 short use_ehlo = FALSE;
 117 short ssl_established = 0;
 118 char *localhostname = NULL;
 119 int sd;
 120 char buffer[MAX_INPUT_BUFFER];
 121 enum {
 122   TCP_PROTOCOL = 1,
 123   UDP_PROTOCOL = 2,
 124 };
 125
 126
 127 int
 128 main (int argc, char **argv)
 129 {
 130         short supports_tls=FALSE;
 131         int n = 0;
 132         double elapsed_time;
 133         long microsec;
 134         int result = STATE_UNKNOWN;
 135         char *cmd_str = NULL;
 136         char *helocmd = NULL;
 137         char *error_msg = "";
 138         struct timeval tv;
 139
 140         setlocale (LC_ALL, "");
 141         bindtextdomain (PACKAGE, LOCALEDIR);
 142         textdomain (PACKAGE);
 143
 144         if (process_arguments (argc, argv) == ERROR)
 145                 usage4 (_("Could not parse arguments"));
 146
 147         /* If localhostname not set on command line, use gethostname to set */
 148         if(! localhostname){
 149                 localhostname = malloc (HOST_MAX_BYTES);
 150                 if(!localhostname){
 151                         printf(_("malloc() failed!\n"));
 152                         return STATE_CRITICAL;
 153                 }
 154                 if(gethostname(localhostname, HOST_MAX_BYTES)){
 155                         printf(_("gethostname() failed!\n"));
 156                         return STATE_CRITICAL;
 157                 }
 158         }
 159         if(use_ehlo)
 160                 asprintf (&helocmd, "%s%s%s", SMTP_EHLO, localhostname, "\r\n");
 161         else
 162                 asprintf (&helocmd, "%s%s%s", SMTP_HELO, localhostname, "\r\n");
 163
 164         if (verbose)
 165                 printf("HELOCMD: %s", helocmd);
 166
 167         /* initialize the MAIL command with optional FROM command  */
 168         asprintf (&cmd_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
 169
 170         if (verbose && smtp_use_dummycmd)
 171                 printf ("FROM CMD: %s", cmd_str);
 172
 173         /* initialize alarm signal handling */
 174         (void) signal (SIGALRM, socket_timeout_alarm_handler);
 175
 176         /* set socket timeout */
 177         (void) alarm (socket_timeout);
 178
 179         /* start timer */
 180         gettimeofday (&tv, NULL);
 181
 182         /* try to connect to the host at the given port number */
 183         result = my_tcp_connect (server_address, server_port, &sd);
 184
 185         if (result == STATE_OK) { /* we connected */
 186
 187                 /* watch for the SMTP connection string and */
 188                 /* return a WARNING status if we couldn't read any data */
 189                 if (recvlines(buffer, MAX_INPUT_BUFFER) <= 0) {
 190                         printf (_("recv() failed\n"));
 191                         result = STATE_WARNING;
 192                 }
 193                 else {
 194                         if (verbose)
 195                                 printf ("%s", buffer);
 196                         /* strip the buffer of carriage returns */
 197                         strip (buffer);
 198                         /* make sure we find the response we are looking for */
 199                         if (!strstr (buffer, server_expect)) {
 200                                 if (server_port == SMTP_PORT)
 201                                         printf (_("Invalid SMTP response received from host\n"));
 202                                 else
 203                                         printf (_("Invalid SMTP response received from host on port %d\n"),
 204                                                                         server_port);
 205                                 result = STATE_WARNING;
 206                         }
 207                 }
 208
 209                 /* send the HELO/EHLO command */
 210                 send(sd, helocmd, strlen(helocmd), 0);
 211
 212                 /* allow for response to helo command to reach us */
 213                 if (recvlines(buffer, MAX_INPUT_BUFFER) <= 0) {
 214                         printf (_("recv() failed\n"));
 215                         return STATE_WARNING;
 216                 } else if(use_ehlo){
 217                         if(strstr(buffer, "250 STARTTLS") != NULL ||
 218                            strstr(buffer, "250-STARTTLS") != NULL){
 219                                 supports_tls=TRUE;
 220                         }
 221                 }
 222
 223                 if(use_ssl && ! supports_tls){
 224                         printf(_("WARNING - TLS not supported by server\n"));
 225                         smtp_quit();
 226                         return STATE_WARNING;
 227                 }
 228
 229 #ifdef HAVE_SSL
 230                 if(use_ssl) {
 231                   /* send the STARTTLS command */
 232                   send(sd, SMTP_STARTTLS, strlen(SMTP_STARTTLS), 0);
 233
 234                   recvlines(buffer, MAX_INPUT_BUFFER); /* wait for it */
 235                   if (!strstr (buffer, server_expect)) {
 236                     printf (_("Server does not support STARTTLS\n"));
 237                     smtp_quit();
 238                     return STATE_UNKNOWN;
 239                   }
 240                   result = np_net_ssl_init(sd);
 241                   if(result != STATE_OK) {
 242                     printf (_("CRITICAL - Cannot create SSL context.\n"));
 243                     np_net_ssl_cleanup();
 244                     close(sd);
 245                     return STATE_CRITICAL;
 246                   } else {
 247                         ssl_established = 1;
 248                   }
 249
 250                 /*
 251                  * Resend the EHLO command.
 252                  *
 253                  * RFC 3207 (4.2) says: ``The client MUST discard any knowledge
 254                  * obtained from the server, such as the list of SMTP service
 255                  * extensions, which was not obtained from the TLS negotiation
 256                  * itself.  The client SHOULD send an EHLO command as the first
 257                  * command after a successful TLS negotiation.''  For this
 258                  * reason, some MTAs will not allow an AUTH LOGIN command before
 259                  * we resent EHLO via TLS.
 260                  */
 261                 if (my_send(helocmd, strlen(helocmd)) <= 0) {
 262                         printf("%s\n", _("SMTP UNKNOWN - Cannot send EHLO command via TLS."));
 263                         my_close();
 264                         return STATE_UNKNOWN;
 265                 }
 266                 if (verbose)
 267                         printf(_("sent %s"), helocmd);
 268                 if ((n = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 269                         printf("%s\n", _("SMTP UNKNOWN - Cannot read EHLO response via TLS."));
 270                         my_close();
 271                         return STATE_UNKNOWN;
 272                 }
 273                 if (verbose) {
 274                         printf("%s", buffer);
 275                 }
 276
 277 #  ifdef USE_OPENSSL
 278                   if ( check_cert ) {
 279                     result = np_net_ssl_check_cert(days_till_exp);
 280                     if(result != STATE_OK){
 281                       printf ("%s\n", _("CRITICAL - Cannot retrieve server certificate."));
 282                     }
 283                     my_close();
 284                     return result;
 285                   }
 286 #  endif /* USE_OPENSSL */
 287                 }
 288 #endif
 289
 290                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 291                  * to do something useful. This can be prevented by giving a command
 292                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 293                  *
 294                  * According to rfc821 you can include a null reversepath in the from command
 295                  * - but a log message is generated on the smtp server.
 296                  *
 297                  * You can disable sending mail_command with '--nocommand'
 298                  * Use the -f option to provide a FROM address
 299                  */
 300                 if (smtp_use_dummycmd) {
 301                   my_send(cmd_str, strlen(cmd_str));
 302                   if (recvlines(buffer, MAX_INPUT_BUFFER) >= 1 && verbose)
 303                     printf("%s", buffer);
 304                 }
 305
 306                 while (n < ncommands) {
 307                         asprintf (&cmd_str, "%s%s", commands[n], "\r\n");
 308                         my_send(cmd_str, strlen(cmd_str));
 309                         if (recvlines(buffer, MAX_INPUT_BUFFER) >= 1 && verbose)
 310                                 printf("%s", buffer);
 311                         strip (buffer);
 312                         if (n < nresponses) {
 313                                 cflags |= REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
 314                                 errcode = regcomp (&preg, responses[n], cflags);
 315                                 if (errcode != 0) {
 316                                         regerror (errcode, &preg, errbuf, MAX_INPUT_BUFFER);
 317                                         printf (_("Could Not Compile Regular Expression"));
 318                                         return ERROR;
 319                                 }
 320                                 excode = regexec (&preg, buffer, 10, pmatch, eflags);
 321                                 if (excode == 0) {
 322                                         result = STATE_OK;
 323                                 }
 324                                 else if (excode == REG_NOMATCH) {
 325                                         result = STATE_WARNING;
 326                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 327                                 }
 328                                 else {
 329                                         regerror (excode, &preg, errbuf, MAX_INPUT_BUFFER);
 330                                         printf (_("Execute Error: %s\n"), errbuf);
 331                                         result = STATE_UNKNOWN;
 332                                 }
 333                         }
 334                         n++;
 335                 }
 336
 337                 if (authtype != NULL) {
 338                         if (strcmp (authtype, "LOGIN") == 0) {
 339                                 char *abuf;
 340                                 int ret;
 341                                 do {
 342                                         if (authuser == NULL) {
 343                                                 result = STATE_CRITICAL;
 344                                                 asprintf(&error_msg, _("no authuser specified, "));
 345                                                 break;
 346                                         }
 347                                         if (authpass == NULL) {
 348                                                 result = STATE_CRITICAL;
 349                                                 asprintf(&error_msg, _("no authpass specified, "));
 350                                                 break;
 351                                         }
 352
 353                                         /* send AUTH LOGIN */
 354                                         my_send(SMTP_AUTH_LOGIN, strlen(SMTP_AUTH_LOGIN));
 355                                         if (verbose)
 356                                                 printf (_("sent %s\n"), "AUTH LOGIN");
 357
 358                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 359                                                 asprintf(&error_msg, _("recv() failed after AUTH LOGIN, "));
 360                                                 result = STATE_WARNING;
 361                                                 break;
 362                                         }
 363                                         if (verbose)
 364                                                 printf (_("received %s\n"), buffer);
 365
 366                                         if (strncmp (buffer, "334", 3) != 0) {
 367                                                 result = STATE_CRITICAL;
 368                                                 asprintf(&error_msg, _("invalid response received after AUTH LOGIN, "));
 369                                                 break;
 370                                         }
 371
 372                                         /* encode authuser with base64 */
 373                                         abuf = base64 (authuser, strlen(authuser));
 374                                         strcat (abuf, "\r\n");
 375                                         my_send(abuf, strlen(abuf));
 376                                         if (verbose)
 377                                                 printf (_("sent %s\n"), abuf);
 378
 379                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 380                                                 result = STATE_CRITICAL;
 381                                                 asprintf(&error_msg, _("recv() failed after sending authuser, "));
 382                                                 break;
 383                                         }
 384                                         if (verbose) {
 385                                                 printf (_("received %s\n"), buffer);
 386                                         }
 387                                         if (strncmp (buffer, "334", 3) != 0) {
 388                                                 result = STATE_CRITICAL;
 389                                                 asprintf(&error_msg, _("invalid response received after authuser, "));
 390                                                 break;
 391                                         }
 392                                         /* encode authpass with base64 */
 393                                         abuf = base64 (authpass, strlen(authpass));
 394                                         strcat (abuf, "\r\n");
 395                                         my_send(abuf, strlen(abuf));
 396                                         if (verbose) {
 397                                                 printf (_("sent %s\n"), abuf);
 398                                         }
 399                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 400                                                 result = STATE_CRITICAL;
 401                                                 asprintf(&error_msg, _("recv() failed after sending authpass, "));
 402                                                 break;
 403                                         }
 404                                         if (verbose) {
 405                                                 printf (_("received %s\n"), buffer);
 406                                         }
 407                                         if (strncmp (buffer, "235", 3) != 0) {
 408                                                 result = STATE_CRITICAL;
 409                                                 asprintf(&error_msg, _("invalid response received after authpass, "));
 410                                                 break;
 411                                         }
 412                                         break;
 413                                 } while (0);
 414                         } else {
 415                                 result = STATE_CRITICAL;
 416                                 asprintf(&error_msg, _("only authtype LOGIN is supported, "));
 417                         }
 418                 }
 419
 420                 /* tell the server we're done */
 421                 smtp_quit();
 422
 423                 /* finally close the connection */
 424                 close (sd);
 425         }
 426
 427         /* reset the alarm */
 428         alarm (0);
 429
 430         microsec = deltime (tv);
 431         elapsed_time = (double)microsec / 1.0e6;
 432
 433         if (result == STATE_OK) {
 434                 if (check_critical_time && elapsed_time > (double) critical_time)
 435                         result = STATE_CRITICAL;
 436                 else if (check_warning_time && elapsed_time > (double) warning_time)
 437                         result = STATE_WARNING;
 438         }
 439
 440         printf (_("SMTP %s - %s%.3f sec. response time%s%s|%s\n"),
 441                         state_text (result),
 442                         error_msg,
 443                         elapsed_time,
 444                         verbose?", ":"", verbose?buffer:"",
 445                         fperfdata ("time", elapsed_time, "s",
 446                                 (int)check_warning_time, warning_time,
 447                                 (int)check_critical_time, critical_time,
 448                                 TRUE, 0, FALSE, 0));
 449
 450         return result;
 451 }
 452
 453
 454
 455 /* process command-line arguments */
 456 int
 457 process_arguments (int argc, char **argv)
 458 {
 459         int c;
 460
 461         int option = 0;
 462         static struct option longopts[] = {
 463                 {"hostname", required_argument, 0, 'H'},
 464                 {"expect", required_argument, 0, 'e'},
 465                 {"critical", required_argument, 0, 'c'},
 466                 {"warning", required_argument, 0, 'w'},
 467                 {"timeout", required_argument, 0, 't'},
 468                 {"port", required_argument, 0, 'p'},
 469                 {"from", required_argument, 0, 'f'},
 470                 {"fqdn", required_argument, 0, 'F'},
 471                 {"authtype", required_argument, 0, 'A'},
 472                 {"authuser", required_argument, 0, 'U'},
 473                 {"authpass", required_argument, 0, 'P'},
 474                 {"command", required_argument, 0, 'C'},
 475                 {"response", required_argument, 0, 'R'},
 476                 {"nocommand", required_argument, 0, 'n'},
 477                 {"verbose", no_argument, 0, 'v'},
 478                 {"version", no_argument, 0, 'V'},
 479                 {"use-ipv4", no_argument, 0, '4'},
 480                 {"use-ipv6", no_argument, 0, '6'},
 481                 {"help", no_argument, 0, 'h'},
 482                 {"starttls",no_argument,0,'S'},
 483                 {"certificate",required_argument,0,'D'},
 484                 {0, 0, 0, 0}
 485         };
 486
 487         if (argc < 2)
 488                 return ERROR;
 489
 490         for (c = 1; c < argc; c++) {
 491                 if (strcmp ("-to", argv[c]) == 0)
 492                         strcpy (argv[c], "-t");
 493                 else if (strcmp ("-wt", argv[c]) == 0)
 494                         strcpy (argv[c], "-w");
 495                 else if (strcmp ("-ct", argv[c]) == 0)
 496                         strcpy (argv[c], "-c");
 497         }
 498
 499         while (1) {
 500                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:SD:F:A:U:P:",
 501                                  longopts, &option);
 502
 503                 if (c == -1 || c == EOF)
 504                         break;
 505
 506                 switch (c) {
 507                 case 'H':                                                                       /* hostname */
 508                         if (is_host (optarg)) {
 509                                 server_address = optarg;
 510                         }
 511                         else {
 512                                 usage2 (_("Invalid hostname/address"), optarg);
 513                         }
 514                         break;
 515                 case 'p':                                                                       /* port */
 516                         if (is_intpos (optarg))
 517                                 server_port = atoi (optarg);
 518                         else
 519                                 usage4 (_("Port must be a positive integer"));
 520                         break;
 521                 case 'F':
 522                 /* localhostname */
 523                         localhostname = strdup(optarg);
 524                         break;
 525                 case 'f':                                                                       /* from argument */
 526                         from_arg = optarg;
 527                         smtp_use_dummycmd = 1;
 528                         break;
 529                 case 'A':
 530                         authtype = optarg;
 531                         use_ehlo = TRUE;
 532                         break;
 533                 case 'U':
 534                         authuser = optarg;
 535                         break;
 536                 case 'P':
 537                         authpass = optarg;
 538                         break;
 539                 case 'e':                                                                       /* server expect string on 220  */
 540                         server_expect = optarg;
 541                         break;
 542                 case 'C':                                                                       /* commands  */
 543                         if (ncommands >= command_size) {
 544                                 command_size+=8;
 545                                 commands = realloc (commands, sizeof(char *) * command_size);
 546                                 if (commands == NULL)
 547                                         die (STATE_UNKNOWN,
 548                                              _("Could not realloc() units [%d]\n"), ncommands);
 549                         }
 550                         commands[ncommands] = (char *) malloc (sizeof(char) * 255);
 551                         strncpy (commands[ncommands], optarg, 255);
 552                         ncommands++;
 553                         break;
 554                 case 'R':                                                                       /* server responses */
 555                         if (nresponses >= response_size) {
 556                                 response_size += 8;
 557                                 responses = realloc (responses, sizeof(char *) * response_size);
 558                                 if (responses == NULL)
 559                                         die (STATE_UNKNOWN,
 560                                              _("Could not realloc() units [%d]\n"), nresponses);
 561                         }
 562                         responses[nresponses] = (char *) malloc (sizeof(char) * 255);
 563                         strncpy (responses[nresponses], optarg, 255);
 564                         nresponses++;
 565                         break;
 566                 case 'c':                                                                       /* critical time threshold */
 567                         if (is_intnonneg (optarg)) {
 568                                 critical_time = atoi (optarg);
 569                                 check_critical_time = TRUE;
 570                         }
 571                         else {
 572                                 usage4 (_("Critical time must be a positive integer"));
 573                         }
 574                         break;
 575                 case 'w':                                                                       /* warning time threshold */
 576                         if (is_intnonneg (optarg)) {
 577                                 warning_time = atoi (optarg);
 578                                 check_warning_time = TRUE;
 579                         }
 580                         else {
 581                                 usage4 (_("Warning time must be a positive integer"));
 582                         }
 583                         break;
 584                 case 'v':                                                                       /* verbose */
 585                         verbose++;
 586                         break;
 587                 case 't':                                                                       /* timeout */
 588                         if (is_intnonneg (optarg)) {
 589                                 socket_timeout = atoi (optarg);
 590                         }
 591                         else {
 592                                 usage4 (_("Timeout interval must be a positive integer"));
 593                         }
 594                         break;
 595                 case 'S':
 596                 /* starttls */
 597                         use_ssl = TRUE;
 598                         use_ehlo = TRUE;
 599                         break;
 600                 case 'D':
 601                 /* Check SSL cert validity */
 602 #ifdef USE_OPENSSL
 603                         if (!is_intnonneg (optarg))
 604                                 usage2 ("Invalid certificate expiration period",optarg);
 605                                 days_till_exp = atoi (optarg);
 606                                 check_cert = TRUE;
 607 #else
 608                                 usage (_("SSL support not available - install OpenSSL and recompile"));
 609 #endif
 610                         break;
 611                 case '4':
 612                         address_family = AF_INET;
 613                         break;
 614                 case '6':
 615 #ifdef USE_IPV6
 616                         address_family = AF_INET6;
 617 #else
 618                         usage4 (_("IPv6 support not available"));
 619 #endif
 620                         break;
 621                 case 'V':                                                                       /* version */
 622                         print_revision (progname, revision);
 623                         exit (STATE_OK);
 624                 case 'h':                                                                       /* help */
 625                         print_help ();
 626                         exit (STATE_OK);
 627                 case '?':                                                                       /* help */
 628                         usage5 ();
 629                 }
 630         }
 631
 632         c = optind;
 633         if (server_address == NULL) {
 634                 if (argv[c]) {
 635                         if (is_host (argv[c]))
 636                                 server_address = argv[c];
 637                         else
 638                                 usage2 (_("Invalid hostname/address"), argv[c]);
 639                 }
 640                 else {
 641                         asprintf (&server_address, "127.0.0.1");
 642                 }
 643         }
 644
 645         if (server_expect == NULL)
 646                 server_expect = strdup (SMTP_EXPECT);
 647
 648         if (mail_command == NULL)
 649                 mail_command = strdup("MAIL ");
 650
 651         if (from_arg==NULL)
 652                 from_arg = strdup(" ");
 653
 654         return validate_arguments ();
 655 }
 656
 657
 658
 659 int
 660 validate_arguments (void)
 661 {
 662         return OK;
 663 }
 664
 665
 666 void
 667 smtp_quit(void)
 668 {
 669         int bytes;
 670
 671         my_send(SMTP_QUIT, strlen(SMTP_QUIT));
 672         if (verbose)
 673                 printf(_("sent %s\n"), "QUIT");
 674
 675         /* read the response but don't care about problems */
 676         bytes = recvlines(buffer, MAX_INPUT_BUFFER);
 677         if (verbose) {
 678                 if (bytes < 0)
 679                         printf(_("recv() failed after QUIT."));
 680                 else if (bytes == 0)
 681                         printf(_("Connection reset by peer."));
 682                 else {
 683                         buffer[bytes] = '\0';
 684                         printf(_("received %s\n"), buffer);
 685                 }
 686         }
 687 }
 688
 689
 690 /*
 691  * Receive one line, copy it into buf and nul-terminate it.  Returns the
 692  * number of bytes written to buf (excluding the '\0') or 0 on EOF or <0 on
 693  * error.
 694  *
 695  * TODO: Reading one byte at a time is very inefficient.  Replace this by a
 696  * function which buffers the data, move that to netutils.c and change
 697  * check_smtp and other plugins to use that.  Also, remove (\r)\n.
 698  */
 699 int
 700 recvline(char *buf, size_t bufsize)
 701 {
 702         int result;
 703         unsigned i;
 704
 705         for (i = result = 0; i < bufsize - 1; i++) {
 706                 if ((result = my_recv(&buf[i], 1)) != 1)
 707                         break;
 708                 if (buf[i] == '\n') {
 709                         buf[++i] = '\0';
 710                         return i;
 711                 }
 712         }
 713         return (result == 1 || i == 0) ? -2 : result;   /* -2 if out of space */
 714 }
 715
 716
 717 /*
 718  * Receive one or more lines, copy them into buf and nul-terminate it.  Returns
 719  * the number of bytes written to buf (excluding the '\0') or 0 on EOF or <0 on
 720  * error.  Works for all protocols which format multiline replies as follows:
 721  *
 722  * ``The format for multiline replies requires that every line, except the last,
 723  * begin with the reply code, followed immediately by a hyphen, `-' (also known
 724  * as minus), followed by text.  The last line will begin with the reply code,
 725  * followed immediately by <SP>, optionally some text, and <CRLF>.  As noted
 726  * above, servers SHOULD send the <SP> if subsequent text is not sent, but
 727  * clients MUST be prepared for it to be omitted.'' (RFC 2821, 4.2.1)
 728  *
 729  * TODO: Move this to netutils.c.  Also, remove \r and possibly the final \n.
 730  */
 731 int
 732 recvlines(char *buf, size_t bufsize)
 733 {
 734         int result, i;
 735
 736         for (i = 0; /* forever */; i += result)
 737                 if (!((result = recvline(buf + i, bufsize - i)) > 3 &&
 738                     isdigit((int)buf[i]) &&
 739                     isdigit((int)buf[i + 1]) &&
 740                     isdigit((int)buf[i + 2]) &&
 741                     buf[i + 3] == '-'))
 742                         break;
 743
 744         return (result <= 0) ? result : result + i;
 745 }
 746
 747
 748 int
 749 my_close (void)
 750 {
 751 #ifdef HAVE_SSL
 752   np_net_ssl_cleanup();
 753 #endif
 754   return close(sd);
 755 }
 756
 757
 758 void
 759 print_help (void)
 760 {
 761         char *myport;
 762         asprintf (&myport, "%d", SMTP_PORT);
 763
 764         print_revision (progname, revision);
 765
 766         printf ("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n");
 767         printf (COPYRIGHT, copyright, email);
 768
 769         printf("%s\n", _("This plugin will attempt to open an SMTP connection with the host."));
 770
 771   printf ("\n\n");
 772
 773         print_usage ();
 774
 775         printf (_(UT_HELP_VRSN));
 776
 777         printf (_(UT_HOST_PORT), 'p', myport);
 778
 779         printf (_(UT_IPv46));
 780
 781         printf (" %s\n", "-e, --expect=STRING");
 782   printf (_("    String to expect in first line of server response (default: '%s')\n"), SMTP_EXPECT);
 783   printf (" %s\n", "-n, nocommand");
 784   printf ("    %s\n", _("Suppress SMTP command"));
 785   printf (" %s\n", "-C, --command=STRING");
 786   printf ("    %s\n", _("SMTP command (may be used repeatedly)"));
 787   printf (" %s\n", "-R, --command=STRING");
 788   printf ("    %s\n", _("Expected response to command (may be used repeatedly)"));
 789   printf (" %s\n", "-f, --from=STRING");
 790   printf ("    %s\n", _("FROM-address to include in MAIL command, required by Exchange 2000")),
 791 #ifdef HAVE_SSL
 792   printf (" %s\n", "-D, --certificate=INTEGER");
 793   printf ("    %s\n", _("Minimum number of days a certificate has to be valid."));
 794   printf (" %s\n", "-S, --starttls");
 795   printf ("    %s\n", _("Use STARTTLS for the connection."));
 796 #endif
 797
 798         printf (" %s\n", "-A, --authtype=STRING");
 799   printf ("    %s\n", _("SMTP AUTH type to check (default none, only LOGIN supported)"));
 800   printf (" %s\n", "-U, --authuser=STRING");
 801   printf ("    %s\n", _("SMTP AUTH username"));
 802   printf (" %s\n", "-P, --authpass=STRING");
 803   printf ("    %s\n", _("SMTP AUTH password"));
 804
 805         printf (_(UT_WARN_CRIT));
 806
 807         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 808
 809         printf (_(UT_VERBOSE));
 810
 811         printf("\n");
 812         printf ("%s\n", _("Successul connects return STATE_OK, refusals and timeouts return"));
 813   printf ("%s\n", _("STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful"));
 814   printf ("%s\n", _("connects, but incorrect reponse messages from the host result in"));
 815   printf ("%s\n", _("STATE_WARNING return values."));
 816
 817         printf (_(UT_SUPPORT));
 818 }
 819
 820
 821
 822 void
 823 print_usage (void)
 824 {
 825   printf (_("Usage:"));
 826         printf ("%s -H host [-p port] [-e expect] [-C command] [-f from addr]", progname);
 827   printf ("[-A authtype -U authuser -P authpass] [-w warn] [-c crit] [-t timeout]\n");
 828   printf ("[-S] [-D days] [-n] [-v] [-4|-6]\n");
 829 }
 830