plugins/check_smtp.c

   1 /*****************************************************************************
   2 *
   3 * Nagios check_smtp plugin
   4 *
   5 * License: GPL
   6 * Copyright (c) 2000-2007 Nagios Plugins Development Team
   7 *
   8 * Description:
   9 *
  10 * This file contains the check_smtp plugin
  11 *
  12 * This plugin will attempt to open an SMTP connection with the host.
  13 *
  14 *
  15 * This program is free software: you can redistribute it and/or modify
  16 * it under the terms of the GNU General Public License as published by
  17 * the Free Software Foundation, either version 3 of the License, or
  18 * (at your option) any later version.
  19 *
  20 * This program is distributed in the hope that it will be useful,
  21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 * GNU General Public License for more details.
  24 *
  25 * You should have received a copy of the GNU General Public License
  26 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  27 *
  28 *
  29 *****************************************************************************/
  30
  31 const char *progname = "check_smtp";
  32 const char *copyright = "2000-2007";
  33 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  34
  35 #include "common.h"
  36 #include "netutils.h"
  37 #include "utils.h"
  38 #include "base64.h"
  39
  40 #include <ctype.h>
  41
  42 #ifdef HAVE_SSL
  43 int check_cert = FALSE;
  44 int days_till_exp;
  45 #  define my_recv(buf, len) ((use_ssl && ssl_established) ? np_net_ssl_read(buf, len) : read(sd, buf, len))
  46 #  define my_send(buf, len) ((use_ssl && ssl_established) ? np_net_ssl_write(buf, len) : send(sd, buf, len, 0))
  47 #else /* ifndef HAVE_SSL */
  48 #  define my_recv(buf, len) read(sd, buf, len)
  49 #  define my_send(buf, len) send(sd, buf, len, 0)
  50 #endif
  51
  52 enum {
  53         SMTP_PORT       = 25
  54 };
  55 #define SMTP_EXPECT "220"
  56 #define SMTP_HELO "HELO "
  57 #define SMTP_EHLO "EHLO "
  58 #define SMTP_QUIT "QUIT\r\n"
  59 #define SMTP_STARTTLS "STARTTLS\r\n"
  60 #define SMTP_AUTH_LOGIN "AUTH LOGIN\r\n"
  61
  62 #ifndef HOST_MAX_BYTES
  63 #define HOST_MAX_BYTES 255
  64 #endif
  65
  66 #define EHLO_SUPPORTS_STARTTLS 1
  67
  68 int process_arguments (int, char **);
  69 int validate_arguments (void);
  70 void print_help (void);
  71 void print_usage (void);
  72 void smtp_quit(void);
  73 int recvline(char *, size_t);
  74 int recvlines(char *, size_t);
  75 int my_close(void);
  76
  77 #include "regex.h"
  78 char regex_expect[MAX_INPUT_BUFFER] = "";
  79 regex_t preg;
  80 regmatch_t pmatch[10];
  81 char timestamp[20] = "";
  82 char errbuf[MAX_INPUT_BUFFER];
  83 int cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
  84 int eflags = 0;
  85 int errcode, excode;
  86
  87 int server_port = SMTP_PORT;
  88 char *server_address = NULL;
  89 char *server_expect = NULL;
  90 int smtp_use_dummycmd = 0;
  91 char *mail_command = NULL;
  92 char *from_arg = NULL;
  93 int ncommands=0;
  94 int command_size=0;
  95 int nresponses=0;
  96 int response_size=0;
  97 char **commands = NULL;
  98 char **responses = NULL;
  99 char *authtype = NULL;
 100 char *authuser = NULL;
 101 char *authpass = NULL;
 102 int warning_time = 0;
 103 int check_warning_time = FALSE;
 104 int critical_time = 0;
 105 int check_critical_time = FALSE;
 106 int verbose = 0;
 107 int use_ssl = FALSE;
 108 short use_ehlo = FALSE;
 109 short ssl_established = 0;
 110 char *localhostname = NULL;
 111 int sd;
 112 char buffer[MAX_INPUT_BUFFER];
 113 enum {
 114   TCP_PROTOCOL = 1,
 115   UDP_PROTOCOL = 2,
 116 };
 117
 118
 119 int
 120 main (int argc, char **argv)
 121 {
 122         short supports_tls=FALSE;
 123         int n = 0;
 124         double elapsed_time;
 125         long microsec;
 126         int result = STATE_UNKNOWN;
 127         char *cmd_str = NULL;
 128         char *helocmd = NULL;
 129         char *error_msg = "";
 130         struct timeval tv;
 131
 132         setlocale (LC_ALL, "");
 133         bindtextdomain (PACKAGE, LOCALEDIR);
 134         textdomain (PACKAGE);
 135
 136         /* Parse extra opts if any */
 137         argv=np_extra_opts (&argc, argv, progname);
 138
 139         if (process_arguments (argc, argv) == ERROR)
 140                 usage4 (_("Could not parse arguments"));
 141
 142         /* If localhostname not set on command line, use gethostname to set */
 143         if(! localhostname){
 144                 localhostname = malloc (HOST_MAX_BYTES);
 145                 if(!localhostname){
 146                         printf(_("malloc() failed!\n"));
 147                         return STATE_CRITICAL;
 148                 }
 149                 if(gethostname(localhostname, HOST_MAX_BYTES)){
 150                         printf(_("gethostname() failed!\n"));
 151                         return STATE_CRITICAL;
 152                 }
 153         }
 154         if(use_ehlo)
 155                 asprintf (&helocmd, "%s%s%s", SMTP_EHLO, localhostname, "\r\n");
 156         else
 157                 asprintf (&helocmd, "%s%s%s", SMTP_HELO, localhostname, "\r\n");
 158
 159         if (verbose)
 160                 printf("HELOCMD: %s", helocmd);
 161
 162         /* initialize the MAIL command with optional FROM command  */
 163         asprintf (&cmd_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
 164
 165         if (verbose && smtp_use_dummycmd)
 166                 printf ("FROM CMD: %s", cmd_str);
 167
 168         /* initialize alarm signal handling */
 169         (void) signal (SIGALRM, socket_timeout_alarm_handler);
 170
 171         /* set socket timeout */
 172         (void) alarm (socket_timeout);
 173
 174         /* start timer */
 175         gettimeofday (&tv, NULL);
 176
 177         /* try to connect to the host at the given port number */
 178         result = my_tcp_connect (server_address, server_port, &sd);
 179
 180         if (result == STATE_OK) { /* we connected */
 181
 182                 /* watch for the SMTP connection string and */
 183                 /* return a WARNING status if we couldn't read any data */
 184                 if (recvlines(buffer, MAX_INPUT_BUFFER) <= 0) {
 185                         printf (_("recv() failed\n"));
 186                         result = STATE_WARNING;
 187                 }
 188                 else {
 189                         if (verbose)
 190                                 printf ("%s", buffer);
 191                         /* strip the buffer of carriage returns */
 192                         strip (buffer);
 193                         /* make sure we find the response we are looking for */
 194                         if (!strstr (buffer, server_expect)) {
 195                                 if (server_port == SMTP_PORT)
 196                                         printf (_("Invalid SMTP response received from host: %s\n"), buffer);
 197                                 else
 198                                         printf (_("Invalid SMTP response received from host on port %d: %s\n"),
 199                                                                         server_port, buffer);
 200                                 result = STATE_WARNING;
 201                         }
 202                 }
 203
 204                 /* send the HELO/EHLO command */
 205                 send(sd, helocmd, strlen(helocmd), 0);
 206
 207                 /* allow for response to helo command to reach us */
 208                 if (recvlines(buffer, MAX_INPUT_BUFFER) <= 0) {
 209                         printf (_("recv() failed\n"));
 210                         return STATE_WARNING;
 211                 } else if(use_ehlo){
 212                         if(strstr(buffer, "250 STARTTLS") != NULL ||
 213                            strstr(buffer, "250-STARTTLS") != NULL){
 214                                 supports_tls=TRUE;
 215                         }
 216                 }
 217
 218                 if(use_ssl && ! supports_tls){
 219                         printf(_("WARNING - TLS not supported by server\n"));
 220                         smtp_quit();
 221                         return STATE_WARNING;
 222                 }
 223
 224 #ifdef HAVE_SSL
 225                 if(use_ssl) {
 226                   /* send the STARTTLS command */
 227                   send(sd, SMTP_STARTTLS, strlen(SMTP_STARTTLS), 0);
 228
 229                   recvlines(buffer, MAX_INPUT_BUFFER); /* wait for it */
 230                   if (!strstr (buffer, server_expect)) {
 231                     printf (_("Server does not support STARTTLS\n"));
 232                     smtp_quit();
 233                     return STATE_UNKNOWN;
 234                   }
 235                   result = np_net_ssl_init(sd);
 236                   if(result != STATE_OK) {
 237                     printf (_("CRITICAL - Cannot create SSL context.\n"));
 238                     np_net_ssl_cleanup();
 239                     close(sd);
 240                     return STATE_CRITICAL;
 241                   } else {
 242                         ssl_established = 1;
 243                   }
 244
 245                 /*
 246                  * Resend the EHLO command.
 247                  *
 248                  * RFC 3207 (4.2) says: ``The client MUST discard any knowledge
 249                  * obtained from the server, such as the list of SMTP service
 250                  * extensions, which was not obtained from the TLS negotiation
 251                  * itself.  The client SHOULD send an EHLO command as the first
 252                  * command after a successful TLS negotiation.''  For this
 253                  * reason, some MTAs will not allow an AUTH LOGIN command before
 254                  * we resent EHLO via TLS.
 255                  */
 256                 if (my_send(helocmd, strlen(helocmd)) <= 0) {
 257                         printf("%s\n", _("SMTP UNKNOWN - Cannot send EHLO command via TLS."));
 258                         my_close();
 259                         return STATE_UNKNOWN;
 260                 }
 261                 if (verbose)
 262                         printf(_("sent %s"), helocmd);
 263                 if ((n = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 264                         printf("%s\n", _("SMTP UNKNOWN - Cannot read EHLO response via TLS."));
 265                         my_close();
 266                         return STATE_UNKNOWN;
 267                 }
 268                 if (verbose) {
 269                         printf("%s", buffer);
 270                 }
 271
 272 #  ifdef USE_OPENSSL
 273                   if ( check_cert ) {
 274                     result = np_net_ssl_check_cert(days_till_exp);
 275                     if(result != STATE_OK){
 276                       printf ("%s\n", _("CRITICAL - Cannot retrieve server certificate."));
 277                     }
 278                     my_close();
 279                     return result;
 280                   }
 281 #  endif /* USE_OPENSSL */
 282                 }
 283 #endif
 284
 285                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 286                  * to do something useful. This can be prevented by giving a command
 287                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 288                  *
 289                  * According to rfc821 you can include a null reversepath in the from command
 290                  * - but a log message is generated on the smtp server.
 291                  *
 292                  * You can disable sending mail_command with '--nocommand'
 293                  * Use the -f option to provide a FROM address
 294                  */
 295                 if (smtp_use_dummycmd) {
 296                   my_send(cmd_str, strlen(cmd_str));
 297                   if (recvlines(buffer, MAX_INPUT_BUFFER) >= 1 && verbose)
 298                     printf("%s", buffer);
 299                 }
 300
 301                 while (n < ncommands) {
 302                         asprintf (&cmd_str, "%s%s", commands[n], "\r\n");
 303                         my_send(cmd_str, strlen(cmd_str));
 304                         if (recvlines(buffer, MAX_INPUT_BUFFER) >= 1 && verbose)
 305                                 printf("%s", buffer);
 306                         strip (buffer);
 307                         if (n < nresponses) {
 308                                 cflags |= REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
 309                                 errcode = regcomp (&preg, responses[n], cflags);
 310                                 if (errcode != 0) {
 311                                         regerror (errcode, &preg, errbuf, MAX_INPUT_BUFFER);
 312                                         printf (_("Could Not Compile Regular Expression"));
 313                                         return ERROR;
 314                                 }
 315                                 excode = regexec (&preg, buffer, 10, pmatch, eflags);
 316                                 if (excode == 0) {
 317                                         result = STATE_OK;
 318                                 }
 319                                 else if (excode == REG_NOMATCH) {
 320                                         result = STATE_WARNING;
 321                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 322                                 }
 323                                 else {
 324                                         regerror (excode, &preg, errbuf, MAX_INPUT_BUFFER);
 325                                         printf (_("Execute Error: %s\n"), errbuf);
 326                                         result = STATE_UNKNOWN;
 327                                 }
 328                         }
 329                         n++;
 330                 }
 331
 332                 if (authtype != NULL) {
 333                         if (strcmp (authtype, "LOGIN") == 0) {
 334                                 char *abuf;
 335                                 int ret;
 336                                 do {
 337                                         if (authuser == NULL) {
 338                                                 result = STATE_CRITICAL;
 339                                                 asprintf(&error_msg, _("no authuser specified, "));
 340                                                 break;
 341                                         }
 342                                         if (authpass == NULL) {
 343                                                 result = STATE_CRITICAL;
 344                                                 asprintf(&error_msg, _("no authpass specified, "));
 345                                                 break;
 346                                         }
 347
 348                                         /* send AUTH LOGIN */
 349                                         my_send(SMTP_AUTH_LOGIN, strlen(SMTP_AUTH_LOGIN));
 350                                         if (verbose)
 351                                                 printf (_("sent %s\n"), "AUTH LOGIN");
 352
 353                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 354                                                 asprintf(&error_msg, _("recv() failed after AUTH LOGIN, "));
 355                                                 result = STATE_WARNING;
 356                                                 break;
 357                                         }
 358                                         if (verbose)
 359                                                 printf (_("received %s\n"), buffer);
 360
 361                                         if (strncmp (buffer, "334", 3) != 0) {
 362                                                 result = STATE_CRITICAL;
 363                                                 asprintf(&error_msg, _("invalid response received after AUTH LOGIN, "));
 364                                                 break;
 365                                         }
 366
 367                                         /* encode authuser with base64 */
 368                                         base64_encode_alloc (authuser, strlen(authuser), &abuf);
 369                                         /* FIXME: abuf shouldn't have enough space to strcat a '\r\n' into it. */
 370                                         strcat (abuf, "\r\n");
 371                                         my_send(abuf, strlen(abuf));
 372                                         if (verbose)
 373                                                 printf (_("sent %s\n"), abuf);
 374
 375                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 376                                                 result = STATE_CRITICAL;
 377                                                 asprintf(&error_msg, _("recv() failed after sending authuser, "));
 378                                                 break;
 379                                         }
 380                                         if (verbose) {
 381                                                 printf (_("received %s\n"), buffer);
 382                                         }
 383                                         if (strncmp (buffer, "334", 3) != 0) {
 384                                                 result = STATE_CRITICAL;
 385                                                 asprintf(&error_msg, _("invalid response received after authuser, "));
 386                                                 break;
 387                                         }
 388                                         /* encode authpass with base64 */
 389                                         base64_encode_alloc (authpass, strlen(authpass), &abuf);
 390                                         /* FIXME: abuf shouldn't have enough space to strcat a '\r\n' into it. */
 391                                         strcat (abuf, "\r\n");
 392                                         my_send(abuf, strlen(abuf));
 393                                         if (verbose) {
 394                                                 printf (_("sent %s\n"), abuf);
 395                                         }
 396                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 397                                                 result = STATE_CRITICAL;
 398                                                 asprintf(&error_msg, _("recv() failed after sending authpass, "));
 399                                                 break;
 400                                         }
 401                                         if (verbose) {
 402                                                 printf (_("received %s\n"), buffer);
 403                                         }
 404                                         if (strncmp (buffer, "235", 3) != 0) {
 405                                                 result = STATE_CRITICAL;
 406                                                 asprintf(&error_msg, _("invalid response received after authpass, "));
 407                                                 break;
 408                                         }
 409                                         break;
 410                                 } while (0);
 411                         } else {
 412                                 result = STATE_CRITICAL;
 413                                 asprintf(&error_msg, _("only authtype LOGIN is supported, "));
 414                         }
 415                 }
 416
 417                 /* tell the server we're done */
 418                 smtp_quit();
 419
 420                 /* finally close the connection */
 421                 close (sd);
 422         }
 423
 424         /* reset the alarm */
 425         alarm (0);
 426
 427         microsec = deltime (tv);
 428         elapsed_time = (double)microsec / 1.0e6;
 429
 430         if (result == STATE_OK) {
 431                 if (check_critical_time && elapsed_time > (double) critical_time)
 432                         result = STATE_CRITICAL;
 433                 else if (check_warning_time && elapsed_time > (double) warning_time)
 434                         result = STATE_WARNING;
 435         }
 436
 437         printf (_("SMTP %s - %s%.3f sec. response time%s%s|%s\n"),
 438                         state_text (result),
 439                         error_msg,
 440                         elapsed_time,
 441                         verbose?", ":"", verbose?buffer:"",
 442                         fperfdata ("time", elapsed_time, "s",
 443                                 (int)check_warning_time, warning_time,
 444                                 (int)check_critical_time, critical_time,
 445                                 TRUE, 0, FALSE, 0));
 446
 447         return result;
 448 }
 449
 450
 451
 452 /* process command-line arguments */
 453 int
 454 process_arguments (int argc, char **argv)
 455 {
 456         int c;
 457
 458         int option = 0;
 459         static struct option longopts[] = {
 460                 {"hostname", required_argument, 0, 'H'},
 461                 {"expect", required_argument, 0, 'e'},
 462                 {"critical", required_argument, 0, 'c'},
 463                 {"warning", required_argument, 0, 'w'},
 464                 {"timeout", required_argument, 0, 't'},
 465                 {"port", required_argument, 0, 'p'},
 466                 {"from", required_argument, 0, 'f'},
 467                 {"fqdn", required_argument, 0, 'F'},
 468                 {"authtype", required_argument, 0, 'A'},
 469                 {"authuser", required_argument, 0, 'U'},
 470                 {"authpass", required_argument, 0, 'P'},
 471                 {"command", required_argument, 0, 'C'},
 472                 {"response", required_argument, 0, 'R'},
 473                 {"nocommand", required_argument, 0, 'n'},
 474                 {"verbose", no_argument, 0, 'v'},
 475                 {"version", no_argument, 0, 'V'},
 476                 {"use-ipv4", no_argument, 0, '4'},
 477                 {"use-ipv6", no_argument, 0, '6'},
 478                 {"help", no_argument, 0, 'h'},
 479                 {"starttls",no_argument,0,'S'},
 480                 {"certificate",required_argument,0,'D'},
 481                 {0, 0, 0, 0}
 482         };
 483
 484         if (argc < 2)
 485                 return ERROR;
 486
 487         for (c = 1; c < argc; c++) {
 488                 if (strcmp ("-to", argv[c]) == 0)
 489                         strcpy (argv[c], "-t");
 490                 else if (strcmp ("-wt", argv[c]) == 0)
 491                         strcpy (argv[c], "-w");
 492                 else if (strcmp ("-ct", argv[c]) == 0)
 493                         strcpy (argv[c], "-c");
 494         }
 495
 496         while (1) {
 497                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:SD:F:A:U:P:",
 498                                  longopts, &option);
 499
 500                 if (c == -1 || c == EOF)
 501                         break;
 502
 503                 switch (c) {
 504                 case 'H':                                                                       /* hostname */
 505                         if (is_host (optarg)) {
 506                                 server_address = optarg;
 507                         }
 508                         else {
 509                                 usage2 (_("Invalid hostname/address"), optarg);
 510                         }
 511                         break;
 512                 case 'p':                                                                       /* port */
 513                         if (is_intpos (optarg))
 514                                 server_port = atoi (optarg);
 515                         else
 516                                 usage4 (_("Port must be a positive integer"));
 517                         break;
 518                 case 'F':
 519                 /* localhostname */
 520                         localhostname = strdup(optarg);
 521                         break;
 522                 case 'f':                                                                       /* from argument */
 523                         from_arg = optarg;
 524                         smtp_use_dummycmd = 1;
 525                         break;
 526                 case 'A':
 527                         authtype = optarg;
 528                         use_ehlo = TRUE;
 529                         break;
 530                 case 'U':
 531                         authuser = optarg;
 532                         break;
 533                 case 'P':
 534                         authpass = optarg;
 535                         break;
 536                 case 'e':                                                                       /* server expect string on 220  */
 537                         server_expect = optarg;
 538                         break;
 539                 case 'C':                                                                       /* commands  */
 540                         if (ncommands >= command_size) {
 541                                 command_size+=8;
 542                                 commands = realloc (commands, sizeof(char *) * command_size);
 543                                 if (commands == NULL)
 544                                         die (STATE_UNKNOWN,
 545                                              _("Could not realloc() units [%d]\n"), ncommands);
 546                         }
 547                         commands[ncommands] = (char *) malloc (sizeof(char) * 255);
 548                         strncpy (commands[ncommands], optarg, 255);
 549                         ncommands++;
 550                         break;
 551                 case 'R':                                                                       /* server responses */
 552                         if (nresponses >= response_size) {
 553                                 response_size += 8;
 554                                 responses = realloc (responses, sizeof(char *) * response_size);
 555                                 if (responses == NULL)
 556                                         die (STATE_UNKNOWN,
 557                                              _("Could not realloc() units [%d]\n"), nresponses);
 558                         }
 559                         responses[nresponses] = (char *) malloc (sizeof(char) * 255);
 560                         strncpy (responses[nresponses], optarg, 255);
 561                         nresponses++;
 562                         break;
 563                 case 'c':                                                                       /* critical time threshold */
 564                         if (is_intnonneg (optarg)) {
 565                                 critical_time = atoi (optarg);
 566                                 check_critical_time = TRUE;
 567                         }
 568                         else {
 569                                 usage4 (_("Critical time must be a positive integer"));
 570                         }
 571                         break;
 572                 case 'w':                                                                       /* warning time threshold */
 573                         if (is_intnonneg (optarg)) {
 574                                 warning_time = atoi (optarg);
 575                                 check_warning_time = TRUE;
 576                         }
 577                         else {
 578                                 usage4 (_("Warning time must be a positive integer"));
 579                         }
 580                         break;
 581                 case 'v':                                                                       /* verbose */
 582                         verbose++;
 583                         break;
 584                 case 't':                                                                       /* timeout */
 585                         if (is_intnonneg (optarg)) {
 586                                 socket_timeout = atoi (optarg);
 587                         }
 588                         else {
 589                                 usage4 (_("Timeout interval must be a positive integer"));
 590                         }
 591                         break;
 592                 case 'S':
 593                 /* starttls */
 594                         use_ssl = TRUE;
 595                         use_ehlo = TRUE;
 596                         break;
 597                 case 'D':
 598                 /* Check SSL cert validity */
 599 #ifdef USE_OPENSSL
 600                         if (!is_intnonneg (optarg))
 601                                 usage2 ("Invalid certificate expiration period",optarg);
 602                                 days_till_exp = atoi (optarg);
 603                                 check_cert = TRUE;
 604 #else
 605                                 usage (_("SSL support not available - install OpenSSL and recompile"));
 606 #endif
 607                         break;
 608                 case '4':
 609                         address_family = AF_INET;
 610                         break;
 611                 case '6':
 612 #ifdef USE_IPV6
 613                         address_family = AF_INET6;
 614 #else
 615                         usage4 (_("IPv6 support not available"));
 616 #endif
 617                         break;
 618                 case 'V':                                                                       /* version */
 619                         print_revision (progname, NP_VERSION);
 620                         exit (STATE_OK);
 621                 case 'h':                                                                       /* help */
 622                         print_help ();
 623                         exit (STATE_OK);
 624                 case '?':                                                                       /* help */
 625                         usage5 ();
 626                 }
 627         }
 628
 629         c = optind;
 630         if (server_address == NULL) {
 631                 if (argv[c]) {
 632                         if (is_host (argv[c]))
 633                                 server_address = argv[c];
 634                         else
 635                                 usage2 (_("Invalid hostname/address"), argv[c]);
 636                 }
 637                 else {
 638                         asprintf (&server_address, "127.0.0.1");
 639                 }
 640         }
 641
 642         if (server_expect == NULL)
 643                 server_expect = strdup (SMTP_EXPECT);
 644
 645         if (mail_command == NULL)
 646                 mail_command = strdup("MAIL ");
 647
 648         if (from_arg==NULL)
 649                 from_arg = strdup(" ");
 650
 651         return validate_arguments ();
 652 }
 653
 654
 655
 656 int
 657 validate_arguments (void)
 658 {
 659         return OK;
 660 }
 661
 662
 663 void
 664 smtp_quit(void)
 665 {
 666         int bytes;
 667
 668         my_send(SMTP_QUIT, strlen(SMTP_QUIT));
 669         if (verbose)
 670                 printf(_("sent %s\n"), "QUIT");
 671
 672         /* read the response but don't care about problems */
 673         bytes = recvlines(buffer, MAX_INPUT_BUFFER);
 674         if (verbose) {
 675                 if (bytes < 0)
 676                         printf(_("recv() failed after QUIT."));
 677                 else if (bytes == 0)
 678                         printf(_("Connection reset by peer."));
 679                 else {
 680                         buffer[bytes] = '\0';
 681                         printf(_("received %s\n"), buffer);
 682                 }
 683         }
 684 }
 685
 686
 687 /*
 688  * Receive one line, copy it into buf and nul-terminate it.  Returns the
 689  * number of bytes written to buf (excluding the '\0') or 0 on EOF or <0 on
 690  * error.
 691  *
 692  * TODO: Reading one byte at a time is very inefficient.  Replace this by a
 693  * function which buffers the data, move that to netutils.c and change
 694  * check_smtp and other plugins to use that.  Also, remove (\r)\n.
 695  */
 696 int
 697 recvline(char *buf, size_t bufsize)
 698 {
 699         int result;
 700         unsigned i;
 701
 702         for (i = result = 0; i < bufsize - 1; i++) {
 703                 if ((result = my_recv(&buf[i], 1)) != 1)
 704                         break;
 705                 if (buf[i] == '\n') {
 706                         buf[++i] = '\0';
 707                         return i;
 708                 }
 709         }
 710         return (result == 1 || i == 0) ? -2 : result;   /* -2 if out of space */
 711 }
 712
 713
 714 /*
 715  * Receive one or more lines, copy them into buf and nul-terminate it.  Returns
 716  * the number of bytes written to buf (excluding the '\0') or 0 on EOF or <0 on
 717  * error.  Works for all protocols which format multiline replies as follows:
 718  *
 719  * ``The format for multiline replies requires that every line, except the last,
 720  * begin with the reply code, followed immediately by a hyphen, `-' (also known
 721  * as minus), followed by text.  The last line will begin with the reply code,
 722  * followed immediately by <SP>, optionally some text, and <CRLF>.  As noted
 723  * above, servers SHOULD send the <SP> if subsequent text is not sent, but
 724  * clients MUST be prepared for it to be omitted.'' (RFC 2821, 4.2.1)
 725  *
 726  * TODO: Move this to netutils.c.  Also, remove \r and possibly the final \n.
 727  */
 728 int
 729 recvlines(char *buf, size_t bufsize)
 730 {
 731         int result, i;
 732
 733         for (i = 0; /* forever */; i += result)
 734                 if (!((result = recvline(buf + i, bufsize - i)) > 3 &&
 735                     isdigit((int)buf[i]) &&
 736                     isdigit((int)buf[i + 1]) &&
 737                     isdigit((int)buf[i + 2]) &&
 738                     buf[i + 3] == '-'))
 739                         break;
 740
 741         return (result <= 0) ? result : result + i;
 742 }
 743
 744
 745 int
 746 my_close (void)
 747 {
 748 #ifdef HAVE_SSL
 749   np_net_ssl_cleanup();
 750 #endif
 751   return close(sd);
 752 }
 753
 754
 755 void
 756 print_help (void)
 757 {
 758         char *myport;
 759         asprintf (&myport, "%d", SMTP_PORT);
 760
 761         print_revision (progname, NP_VERSION);
 762
 763         printf ("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n");
 764         printf (COPYRIGHT, copyright, email);
 765
 766         printf("%s\n", _("This plugin will attempt to open an SMTP connection with the host."));
 767
 768   printf ("\n\n");
 769
 770         print_usage ();
 771
 772         printf (_(UT_HELP_VRSN));
 773         printf (_(UT_EXTRA_OPTS));
 774
 775         printf (_(UT_HOST_PORT), 'p', myport);
 776
 777         printf (_(UT_IPv46));
 778
 779         printf (" %s\n", "-e, --expect=STRING");
 780   printf (_("    String to expect in first line of server response (default: '%s')\n"), SMTP_EXPECT);
 781   printf (" %s\n", "-n, nocommand");
 782   printf ("    %s\n", _("Suppress SMTP command"));
 783   printf (" %s\n", "-C, --command=STRING");
 784   printf ("    %s\n", _("SMTP command (may be used repeatedly)"));
 785   printf (" %s\n", "-R, --command=STRING");
 786   printf ("    %s\n", _("Expected response to command (may be used repeatedly)"));
 787   printf (" %s\n", "-f, --from=STRING");
 788   printf ("    %s\n", _("FROM-address to include in MAIL command, required by Exchange 2000")),
 789 #ifdef HAVE_SSL
 790   printf (" %s\n", "-D, --certificate=INTEGER");
 791   printf ("    %s\n", _("Minimum number of days a certificate has to be valid."));
 792   printf (" %s\n", "-S, --starttls");
 793   printf ("    %s\n", _("Use STARTTLS for the connection."));
 794 #endif
 795
 796         printf (" %s\n", "-A, --authtype=STRING");
 797   printf ("    %s\n", _("SMTP AUTH type to check (default none, only LOGIN supported)"));
 798   printf (" %s\n", "-U, --authuser=STRING");
 799   printf ("    %s\n", _("SMTP AUTH username"));
 800   printf (" %s\n", "-P, --authpass=STRING");
 801   printf ("    %s\n", _("SMTP AUTH password"));
 802
 803         printf (_(UT_WARN_CRIT));
 804
 805         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 806
 807         printf (_(UT_VERBOSE));
 808
 809         printf("\n");
 810         printf ("%s\n", _("Successul connects return STATE_OK, refusals and timeouts return"));
 811   printf ("%s\n", _("STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful"));
 812   printf ("%s\n", _("connects, but incorrect reponse messages from the host result in"));
 813   printf ("%s\n", _("STATE_WARNING return values."));
 814
 815 #ifdef NP_EXTRA_OPTS
 816   printf ("\n");
 817   printf ("%s\n", _("Notes:"));
 818   printf (_(UT_EXTRA_OPTS_NOTES));
 819 #endif
 820
 821         printf (_(UT_SUPPORT));
 822 }
 823
 824
 825
 826 void
 827 print_usage (void)
 828 {
 829   printf (_("Usage:"));
 830         printf ("%s -H host [-p port] [-e expect] [-C command] [-f from addr]", progname);
 831   printf ("[-A authtype -U authuser -P authpass] [-w warn] [-c crit] [-t timeout]\n");
 832   printf ("[-S] [-D days] [-n] [-v] [-4|-6]\n");
 833 }
 834