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 * 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 * This program is free software: you can redistribute it and/or modify
  18 * it under the terms of the GNU General Public License as published by
  19 * the Free Software Foundation, either version 3 of the License, or
  20 * (at your option) any later version.
  21 *
  22 * This program is distributed in the hope that it will be useful,
  23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  25 * GNU General Public License for more details.
  26 *
  27 * You should have received a copy of the GNU General Public License
  28 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  29 *
  30 * $Id$
  31 *
  32 *****************************************************************************/
  33
  34 const char *progname = "check_smtp";
  35 const char *revision = "$Revision$";
  36 const char *copyright = "2000-2007";
  37 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  38
  39 #include "common.h"
  40 #include "netutils.h"
  41 #include "utils.h"
  42 #include "base64.h"
  43
  44 #include <ctype.h>
  45
  46 #ifdef HAVE_SSL
  47 int check_cert = FALSE;
  48 int days_till_exp;
  49 #  define my_recv(buf, len) ((use_ssl && ssl_established) ? np_net_ssl_read(buf, len) : read(sd, buf, len))
  50 #  define my_send(buf, len) ((use_ssl && ssl_established) ? np_net_ssl_write(buf, len) : send(sd, buf, len, 0))
  51 #else /* ifndef HAVE_SSL */
  52 #  define my_recv(buf, len) read(sd, buf, len)
  53 #  define my_send(buf, len) send(sd, buf, len, 0)
  54 #endif
  55
  56 enum {
  57         SMTP_PORT       = 25
  58 };
  59 #define SMTP_EXPECT "220"
  60 #define SMTP_HELO "HELO "
  61 #define SMTP_EHLO "EHLO "
  62 #define SMTP_QUIT "QUIT\r\n"
  63 #define SMTP_STARTTLS "STARTTLS\r\n"
  64 #define SMTP_AUTH_LOGIN "AUTH LOGIN\r\n"
  65
  66 #ifndef HOST_MAX_BYTES
  67 #define HOST_MAX_BYTES 255
  68 #endif
  69
  70 #define EHLO_SUPPORTS_STARTTLS 1
  71
  72 int process_arguments (int, char **);
  73 int validate_arguments (void);
  74 void print_help (void);
  75 void print_usage (void);
  76 void smtp_quit(void);
  77 int recvline(char *, size_t);
  78 int recvlines(char *, size_t);
  79 int my_close(void);
  80
  81 #include "regex.h"
  82 char regex_expect[MAX_INPUT_BUFFER] = "";
  83 regex_t preg;
  84 regmatch_t pmatch[10];
  85 char timestamp[20] = "";
  86 char errbuf[MAX_INPUT_BUFFER];
  87 int cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
  88 int eflags = 0;
  89 int errcode, excode;
  90
  91 int server_port = SMTP_PORT;
  92 char *server_address = NULL;
  93 char *server_expect = NULL;
  94 int smtp_use_dummycmd = 0;
  95 char *mail_command = NULL;
  96 char *from_arg = NULL;
  97 int ncommands=0;
  98 int command_size=0;
  99 int nresponses=0;
 100 int response_size=0;
 101 char **commands = NULL;
 102 char **responses = NULL;
 103 char *authtype = NULL;
 104 char *authuser = NULL;
 105 char *authpass = NULL;
 106 int warning_time = 0;
 107 int check_warning_time = FALSE;
 108 int critical_time = 0;
 109 int check_critical_time = FALSE;
 110 int verbose = 0;
 111 int use_ssl = FALSE;
 112 short use_ehlo = FALSE;
 113 short ssl_established = 0;
 114 char *localhostname = NULL;
 115 int sd;
 116 char buffer[MAX_INPUT_BUFFER];
 117 enum {
 118   TCP_PROTOCOL = 1,
 119   UDP_PROTOCOL = 2,
 120 };
 121
 122
 123 int
 124 main (int argc, char **argv)
 125 {
 126         short supports_tls=FALSE;
 127         int n = 0;
 128         double elapsed_time;
 129         long microsec;
 130         int result = STATE_UNKNOWN;
 131         char *cmd_str = NULL;
 132         char *helocmd = NULL;
 133         char *error_msg = "";
 134         struct timeval tv;
 135
 136         setlocale (LC_ALL, "");
 137         bindtextdomain (PACKAGE, LOCALEDIR);
 138         textdomain (PACKAGE);
 139
 140         /* Parse extra opts if any */
 141         argv=np_extra_opts (&argc, argv, progname);
 142
 143         if (process_arguments (argc, argv) == ERROR)
 144                 usage4 (_("Could not parse arguments"));
 145
 146         /* If localhostname not set on command line, use gethostname to set */
 147         if(! localhostname){
 148                 localhostname = malloc (HOST_MAX_BYTES);
 149                 if(!localhostname){
 150                         printf(_("malloc() failed!\n"));
 151                         return STATE_CRITICAL;
 152                 }
 153                 if(gethostname(localhostname, HOST_MAX_BYTES)){
 154                         printf(_("gethostname() failed!\n"));
 155                         return STATE_CRITICAL;
 156                 }
 157         }
 158         if(use_ehlo)
 159                 asprintf (&helocmd, "%s%s%s", SMTP_EHLO, localhostname, "\r\n");
 160         else
 161                 asprintf (&helocmd, "%s%s%s", SMTP_HELO, localhostname, "\r\n");
 162
 163         if (verbose)
 164                 printf("HELOCMD: %s", helocmd);
 165
 166         /* initialize the MAIL command with optional FROM command  */
 167         asprintf (&cmd_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
 168
 169         if (verbose && smtp_use_dummycmd)
 170                 printf ("FROM CMD: %s", cmd_str);
 171
 172         /* initialize alarm signal handling */
 173         (void) signal (SIGALRM, socket_timeout_alarm_handler);
 174
 175         /* set socket timeout */
 176         (void) alarm (socket_timeout);
 177
 178         /* start timer */
 179         gettimeofday (&tv, NULL);
 180
 181         /* try to connect to the host at the given port number */
 182         result = my_tcp_connect (server_address, server_port, &sd);
 183
 184         if (result == STATE_OK) { /* we connected */
 185
 186                 /* watch for the SMTP connection string and */
 187                 /* return a WARNING status if we couldn't read any data */
 188                 if (recvlines(buffer, MAX_INPUT_BUFFER) <= 0) {
 189                         printf (_("recv() failed\n"));
 190                         result = STATE_WARNING;
 191                 }
 192                 else {
 193                         if (verbose)
 194                                 printf ("%s", buffer);
 195                         /* strip the buffer of carriage returns */
 196                         strip (buffer);
 197                         /* make sure we find the response we are looking for */
 198                         if (!strstr (buffer, server_expect)) {
 199                                 if (server_port == SMTP_PORT)
 200                                         printf (_("Invalid SMTP response received from host: %s\n"), buffer);
 201                                 else
 202                                         printf (_("Invalid SMTP response received from host on port %d: %s\n"),
 203                                                                         server_port, buffer);
 204                                 result = STATE_WARNING;
 205                         }
 206                 }
 207
 208                 /* send the HELO/EHLO command */
 209                 send(sd, helocmd, strlen(helocmd), 0);
 210
 211                 /* allow for response to helo command to reach us */
 212                 if (recvlines(buffer, MAX_INPUT_BUFFER) <= 0) {
 213                         printf (_("recv() failed\n"));
 214                         return STATE_WARNING;
 215                 } else if(use_ehlo){
 216                         if(strstr(buffer, "250 STARTTLS") != NULL ||
 217                            strstr(buffer, "250-STARTTLS") != NULL){
 218                                 supports_tls=TRUE;
 219                         }
 220                 }
 221
 222                 if(use_ssl && ! supports_tls){
 223                         printf(_("WARNING - TLS not supported by server\n"));
 224                         smtp_quit();
 225                         return STATE_WARNING;
 226                 }
 227
 228 #ifdef HAVE_SSL
 229                 if(use_ssl) {
 230                   /* send the STARTTLS command */
 231                   send(sd, SMTP_STARTTLS, strlen(SMTP_STARTTLS), 0);
 232
 233                   recvlines(buffer, MAX_INPUT_BUFFER); /* wait for it */
 234                   if (!strstr (buffer, server_expect)) {
 235                     printf (_("Server does not support STARTTLS\n"));
 236                     smtp_quit();
 237                     return STATE_UNKNOWN;
 238                   }
 239                   result = np_net_ssl_init(sd);
 240                   if(result != STATE_OK) {
 241                     printf (_("CRITICAL - Cannot create SSL context.\n"));
 242                     np_net_ssl_cleanup();
 243                     close(sd);
 244                     return STATE_CRITICAL;
 245                   } else {
 246                         ssl_established = 1;
 247                   }
 248
 249                 /*
 250                  * Resend the EHLO command.
 251                  *
 252                  * RFC 3207 (4.2) says: ``The client MUST discard any knowledge
 253                  * obtained from the server, such as the list of SMTP service
 254                  * extensions, which was not obtained from the TLS negotiation
 255                  * itself.  The client SHOULD send an EHLO command as the first
 256                  * command after a successful TLS negotiation.''  For this
 257                  * reason, some MTAs will not allow an AUTH LOGIN command before
 258                  * we resent EHLO via TLS.
 259                  */
 260                 if (my_send(helocmd, strlen(helocmd)) <= 0) {
 261                         printf("%s\n", _("SMTP UNKNOWN - Cannot send EHLO command via TLS."));
 262                         my_close();
 263                         return STATE_UNKNOWN;
 264                 }
 265                 if (verbose)
 266                         printf(_("sent %s"), helocmd);
 267                 if ((n = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 268                         printf("%s\n", _("SMTP UNKNOWN - Cannot read EHLO response via TLS."));
 269                         my_close();
 270                         return STATE_UNKNOWN;
 271                 }
 272                 if (verbose) {
 273                         printf("%s", buffer);
 274                 }
 275
 276 #  ifdef USE_OPENSSL
 277                   if ( check_cert ) {
 278                     result = np_net_ssl_check_cert(days_till_exp);
 279                     if(result != STATE_OK){
 280                       printf ("%s\n", _("CRITICAL - Cannot retrieve server certificate."));
 281                     }
 282                     my_close();
 283                     return result;
 284                   }
 285 #  endif /* USE_OPENSSL */
 286                 }
 287 #endif
 288
 289                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 290                  * to do something useful. This can be prevented by giving a command
 291                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 292                  *
 293                  * According to rfc821 you can include a null reversepath in the from command
 294                  * - but a log message is generated on the smtp server.
 295                  *
 296                  * You can disable sending mail_command with '--nocommand'
 297                  * Use the -f option to provide a FROM address
 298                  */
 299                 if (smtp_use_dummycmd) {
 300                   my_send(cmd_str, strlen(cmd_str));
 301                   if (recvlines(buffer, MAX_INPUT_BUFFER) >= 1 && verbose)
 302                     printf("%s", buffer);
 303                 }
 304
 305                 while (n < ncommands) {
 306                         asprintf (&cmd_str, "%s%s", commands[n], "\r\n");
 307                         my_send(cmd_str, strlen(cmd_str));
 308                         if (recvlines(buffer, MAX_INPUT_BUFFER) >= 1 && verbose)
 309                                 printf("%s", buffer);
 310                         strip (buffer);
 311                         if (n < nresponses) {
 312                                 cflags |= REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
 313                                 errcode = regcomp (&preg, responses[n], cflags);
 314                                 if (errcode != 0) {
 315                                         regerror (errcode, &preg, errbuf, MAX_INPUT_BUFFER);
 316                                         printf (_("Could Not Compile Regular Expression"));
 317                                         return ERROR;
 318                                 }
 319                                 excode = regexec (&preg, buffer, 10, pmatch, eflags);
 320                                 if (excode == 0) {
 321                                         result = STATE_OK;
 322                                 }
 323                                 else if (excode == REG_NOMATCH) {
 324                                         result = STATE_WARNING;
 325                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 326                                 }
 327                                 else {
 328                                         regerror (excode, &preg, errbuf, MAX_INPUT_BUFFER);
 329                                         printf (_("Execute Error: %s\n"), errbuf);
 330                                         result = STATE_UNKNOWN;
 331                                 }
 332                         }
 333                         n++;
 334                 }
 335
 336                 if (authtype != NULL) {
 337                         if (strcmp (authtype, "LOGIN") == 0) {
 338                                 char *abuf;
 339                                 int ret;
 340                                 do {
 341                                         if (authuser == NULL) {
 342                                                 result = STATE_CRITICAL;
 343                                                 asprintf(&error_msg, _("no authuser specified, "));
 344                                                 break;
 345                                         }
 346                                         if (authpass == NULL) {
 347                                                 result = STATE_CRITICAL;
 348                                                 asprintf(&error_msg, _("no authpass specified, "));
 349                                                 break;
 350                                         }
 351
 352                                         /* send AUTH LOGIN */
 353                                         my_send(SMTP_AUTH_LOGIN, strlen(SMTP_AUTH_LOGIN));
 354                                         if (verbose)
 355                                                 printf (_("sent %s\n"), "AUTH LOGIN");
 356
 357                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 358                                                 asprintf(&error_msg, _("recv() failed after AUTH LOGIN, "));
 359                                                 result = STATE_WARNING;
 360                                                 break;
 361                                         }
 362                                         if (verbose)
 363                                                 printf (_("received %s\n"), buffer);
 364
 365                                         if (strncmp (buffer, "334", 3) != 0) {
 366                                                 result = STATE_CRITICAL;
 367                                                 asprintf(&error_msg, _("invalid response received after AUTH LOGIN, "));
 368                                                 break;
 369                                         }
 370
 371                                         /* encode authuser with base64 */
 372                                         base64_encode_alloc (authuser, strlen(authuser), &abuf);
 373                                         /* FIXME: abuf shouldn't have enough space to strcat a '\r\n' into it. */
 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                                         base64_encode_alloc (authpass, strlen(authpass), &abuf);
 394                                         /* FIXME: abuf shouldn't have enough space to strcat a '\r\n' into it. */
 395                                         strcat (abuf, "\r\n");
 396                                         my_send(abuf, strlen(abuf));
 397                                         if (verbose) {
 398                                                 printf (_("sent %s\n"), abuf);
 399                                         }
 400                                         if ((ret = recvlines(buffer, MAX_INPUT_BUFFER)) <= 0) {
 401                                                 result = STATE_CRITICAL;
 402                                                 asprintf(&error_msg, _("recv() failed after sending authpass, "));
 403                                                 break;
 404                                         }
 405                                         if (verbose) {
 406                                                 printf (_("received %s\n"), buffer);
 407                                         }
 408                                         if (strncmp (buffer, "235", 3) != 0) {
 409                                                 result = STATE_CRITICAL;
 410                                                 asprintf(&error_msg, _("invalid response received after authpass, "));
 411                                                 break;
 412                                         }
 413                                         break;
 414                                 } while (0);
 415                         } else {
 416                                 result = STATE_CRITICAL;
 417                                 asprintf(&error_msg, _("only authtype LOGIN is supported, "));
 418                         }
 419                 }
 420
 421                 /* tell the server we're done */
 422                 smtp_quit();
 423
 424                 /* finally close the connection */
 425                 close (sd);
 426         }
 427
 428         /* reset the alarm */
 429         alarm (0);
 430
 431         microsec = deltime (tv);
 432         elapsed_time = (double)microsec / 1.0e6;
 433
 434         if (result == STATE_OK) {
 435                 if (check_critical_time && elapsed_time > (double) critical_time)
 436                         result = STATE_CRITICAL;
 437                 else if (check_warning_time && elapsed_time > (double) warning_time)
 438                         result = STATE_WARNING;
 439         }
 440
 441         printf (_("SMTP %s - %s%.3f sec. response time%s%s|%s\n"),
 442                         state_text (result),
 443                         error_msg,
 444                         elapsed_time,
 445                         verbose?", ":"", verbose?buffer:"",
 446                         fperfdata ("time", elapsed_time, "s",
 447                                 (int)check_warning_time, warning_time,
 448                                 (int)check_critical_time, critical_time,
 449                                 TRUE, 0, FALSE, 0));
 450
 451         return result;
 452 }
 453
 454
 455
 456 /* process command-line arguments */
 457 int
 458 process_arguments (int argc, char **argv)
 459 {
 460         int c;
 461
 462         int option = 0;
 463         static struct option longopts[] = {
 464                 {"hostname", required_argument, 0, 'H'},
 465                 {"expect", required_argument, 0, 'e'},
 466                 {"critical", required_argument, 0, 'c'},
 467                 {"warning", required_argument, 0, 'w'},
 468                 {"timeout", required_argument, 0, 't'},
 469                 {"port", required_argument, 0, 'p'},
 470                 {"from", required_argument, 0, 'f'},
 471                 {"fqdn", required_argument, 0, 'F'},
 472                 {"authtype", required_argument, 0, 'A'},
 473                 {"authuser", required_argument, 0, 'U'},
 474                 {"authpass", required_argument, 0, 'P'},
 475                 {"command", required_argument, 0, 'C'},
 476                 {"response", required_argument, 0, 'R'},
 477                 {"nocommand", required_argument, 0, 'n'},
 478                 {"verbose", no_argument, 0, 'v'},
 479                 {"version", no_argument, 0, 'V'},
 480                 {"use-ipv4", no_argument, 0, '4'},
 481                 {"use-ipv6", no_argument, 0, '6'},
 482                 {"help", no_argument, 0, 'h'},
 483                 {"starttls",no_argument,0,'S'},
 484                 {"certificate",required_argument,0,'D'},
 485                 {0, 0, 0, 0}
 486         };
 487
 488         if (argc < 2)
 489                 return ERROR;
 490
 491         for (c = 1; c < argc; c++) {
 492                 if (strcmp ("-to", argv[c]) == 0)
 493                         strcpy (argv[c], "-t");
 494                 else if (strcmp ("-wt", argv[c]) == 0)
 495                         strcpy (argv[c], "-w");
 496                 else if (strcmp ("-ct", argv[c]) == 0)
 497                         strcpy (argv[c], "-c");
 498         }
 499
 500         while (1) {
 501                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:SD:F:A:U:P:",
 502                                  longopts, &option);
 503
 504                 if (c == -1 || c == EOF)
 505                         break;
 506
 507                 switch (c) {
 508                 case 'H':                                                                       /* hostname */
 509                         if (is_host (optarg)) {
 510                                 server_address = optarg;
 511                         }
 512                         else {
 513                                 usage2 (_("Invalid hostname/address"), optarg);
 514                         }
 515                         break;
 516                 case 'p':                                                                       /* port */
 517                         if (is_intpos (optarg))
 518                                 server_port = atoi (optarg);
 519                         else
 520                                 usage4 (_("Port must be a positive integer"));
 521                         break;
 522                 case 'F':
 523                 /* localhostname */
 524                         localhostname = strdup(optarg);
 525                         break;
 526                 case 'f':                                                                       /* from argument */
 527                         from_arg = optarg;
 528                         smtp_use_dummycmd = 1;
 529                         break;
 530                 case 'A':
 531                         authtype = optarg;
 532                         use_ehlo = TRUE;
 533                         break;
 534                 case 'U':
 535                         authuser = optarg;
 536                         break;
 537                 case 'P':
 538                         authpass = optarg;
 539                         break;
 540                 case 'e':                                                                       /* server expect string on 220  */
 541                         server_expect = optarg;
 542                         break;
 543                 case 'C':                                                                       /* commands  */
 544                         if (ncommands >= command_size) {
 545                                 command_size+=8;
 546                                 commands = realloc (commands, sizeof(char *) * command_size);
 547                                 if (commands == NULL)
 548                                         die (STATE_UNKNOWN,
 549                                              _("Could not realloc() units [%d]\n"), ncommands);
 550                         }
 551                         commands[ncommands] = (char *) malloc (sizeof(char) * 255);
 552                         strncpy (commands[ncommands], optarg, 255);
 553                         ncommands++;
 554                         break;
 555                 case 'R':                                                                       /* server responses */
 556                         if (nresponses >= response_size) {
 557                                 response_size += 8;
 558                                 responses = realloc (responses, sizeof(char *) * response_size);
 559                                 if (responses == NULL)
 560                                         die (STATE_UNKNOWN,
 561                                              _("Could not realloc() units [%d]\n"), nresponses);
 562                         }
 563                         responses[nresponses] = (char *) malloc (sizeof(char) * 255);
 564                         strncpy (responses[nresponses], optarg, 255);
 565                         nresponses++;
 566                         break;
 567                 case 'c':                                                                       /* critical time threshold */
 568                         if (is_intnonneg (optarg)) {
 569                                 critical_time = atoi (optarg);
 570                                 check_critical_time = TRUE;
 571                         }
 572                         else {
 573                                 usage4 (_("Critical time must be a positive integer"));
 574                         }
 575                         break;
 576                 case 'w':                                                                       /* warning time threshold */
 577                         if (is_intnonneg (optarg)) {
 578                                 warning_time = atoi (optarg);
 579                                 check_warning_time = TRUE;
 580                         }
 581                         else {
 582                                 usage4 (_("Warning time must be a positive integer"));
 583                         }
 584                         break;
 585                 case 'v':                                                                       /* verbose */
 586                         verbose++;
 587                         break;
 588                 case 't':                                                                       /* timeout */
 589                         if (is_intnonneg (optarg)) {
 590                                 socket_timeout = atoi (optarg);
 591                         }
 592                         else {
 593                                 usage4 (_("Timeout interval must be a positive integer"));
 594                         }
 595                         break;
 596                 case 'S':
 597                 /* starttls */
 598                         use_ssl = TRUE;
 599                         use_ehlo = TRUE;
 600                         break;
 601                 case 'D':
 602                 /* Check SSL cert validity */
 603 #ifdef USE_OPENSSL
 604                         if (!is_intnonneg (optarg))
 605                                 usage2 ("Invalid certificate expiration period",optarg);
 606                                 days_till_exp = atoi (optarg);
 607                                 check_cert = TRUE;
 608 #else
 609                                 usage (_("SSL support not available - install OpenSSL and recompile"));
 610 #endif
 611                         break;
 612                 case '4':
 613                         address_family = AF_INET;
 614                         break;
 615                 case '6':
 616 #ifdef USE_IPV6
 617                         address_family = AF_INET6;
 618 #else
 619                         usage4 (_("IPv6 support not available"));
 620 #endif
 621                         break;
 622                 case 'V':                                                                       /* version */
 623                         print_revision (progname, revision);
 624                         exit (STATE_OK);
 625                 case 'h':                                                                       /* help */
 626                         print_help ();
 627                         exit (STATE_OK);
 628                 case '?':                                                                       /* help */
 629                         usage5 ();
 630                 }
 631         }
 632
 633         c = optind;
 634         if (server_address == NULL) {
 635                 if (argv[c]) {
 636                         if (is_host (argv[c]))
 637                                 server_address = argv[c];
 638                         else
 639                                 usage2 (_("Invalid hostname/address"), argv[c]);
 640                 }
 641                 else {
 642                         asprintf (&server_address, "127.0.0.1");
 643                 }
 644         }
 645
 646         if (server_expect == NULL)
 647                 server_expect = strdup (SMTP_EXPECT);
 648
 649         if (mail_command == NULL)
 650                 mail_command = strdup("MAIL ");
 651
 652         if (from_arg==NULL)
 653                 from_arg = strdup(" ");
 654
 655         return validate_arguments ();
 656 }
 657
 658
 659
 660 int
 661 validate_arguments (void)
 662 {
 663         return OK;
 664 }
 665
 666
 667 void
 668 smtp_quit(void)
 669 {
 670         int bytes;
 671
 672         my_send(SMTP_QUIT, strlen(SMTP_QUIT));
 673         if (verbose)
 674                 printf(_("sent %s\n"), "QUIT");
 675
 676         /* read the response but don't care about problems */
 677         bytes = recvlines(buffer, MAX_INPUT_BUFFER);
 678         if (verbose) {
 679                 if (bytes < 0)
 680                         printf(_("recv() failed after QUIT."));
 681                 else if (bytes == 0)
 682                         printf(_("Connection reset by peer."));
 683                 else {
 684                         buffer[bytes] = '\0';
 685                         printf(_("received %s\n"), buffer);
 686                 }
 687         }
 688 }
 689
 690
 691 /*
 692  * Receive one line, copy it into buf and nul-terminate it.  Returns the
 693  * number of bytes written to buf (excluding the '\0') or 0 on EOF or <0 on
 694  * error.
 695  *
 696  * TODO: Reading one byte at a time is very inefficient.  Replace this by a
 697  * function which buffers the data, move that to netutils.c and change
 698  * check_smtp and other plugins to use that.  Also, remove (\r)\n.
 699  */
 700 int
 701 recvline(char *buf, size_t bufsize)
 702 {
 703         int result;
 704         unsigned i;
 705
 706         for (i = result = 0; i < bufsize - 1; i++) {
 707                 if ((result = my_recv(&buf[i], 1)) != 1)
 708                         break;
 709                 if (buf[i] == '\n') {
 710                         buf[++i] = '\0';
 711                         return i;
 712                 }
 713         }
 714         return (result == 1 || i == 0) ? -2 : result;   /* -2 if out of space */
 715 }
 716
 717
 718 /*
 719  * Receive one or more lines, copy them into buf and nul-terminate it.  Returns
 720  * the number of bytes written to buf (excluding the '\0') or 0 on EOF or <0 on
 721  * error.  Works for all protocols which format multiline replies as follows:
 722  *
 723  * ``The format for multiline replies requires that every line, except the last,
 724  * begin with the reply code, followed immediately by a hyphen, `-' (also known
 725  * as minus), followed by text.  The last line will begin with the reply code,
 726  * followed immediately by <SP>, optionally some text, and <CRLF>.  As noted
 727  * above, servers SHOULD send the <SP> if subsequent text is not sent, but
 728  * clients MUST be prepared for it to be omitted.'' (RFC 2821, 4.2.1)
 729  *
 730  * TODO: Move this to netutils.c.  Also, remove \r and possibly the final \n.
 731  */
 732 int
 733 recvlines(char *buf, size_t bufsize)
 734 {
 735         int result, i;
 736
 737         for (i = 0; /* forever */; i += result)
 738                 if (!((result = recvline(buf + i, bufsize - i)) > 3 &&
 739                     isdigit((int)buf[i]) &&
 740                     isdigit((int)buf[i + 1]) &&
 741                     isdigit((int)buf[i + 2]) &&
 742                     buf[i + 3] == '-'))
 743                         break;
 744
 745         return (result <= 0) ? result : result + i;
 746 }
 747
 748
 749 int
 750 my_close (void)
 751 {
 752 #ifdef HAVE_SSL
 753   np_net_ssl_cleanup();
 754 #endif
 755   return close(sd);
 756 }
 757
 758
 759 void
 760 print_help (void)
 761 {
 762         char *myport;
 763         asprintf (&myport, "%d", SMTP_PORT);
 764
 765         print_revision (progname, revision);
 766
 767         printf ("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n");
 768         printf (COPYRIGHT, copyright, email);
 769
 770         printf("%s\n", _("This plugin will attempt to open an SMTP connection with the host."));
 771
 772   printf ("\n\n");
 773
 774         print_usage ();
 775
 776         printf (_(UT_HELP_VRSN));
 777         printf (_(UT_EXTRA_OPTS));
 778
 779         printf (_(UT_HOST_PORT), 'p', myport);
 780
 781         printf (_(UT_IPv46));
 782
 783         printf (" %s\n", "-e, --expect=STRING");
 784   printf (_("    String to expect in first line of server response (default: '%s')\n"), SMTP_EXPECT);
 785   printf (" %s\n", "-n, nocommand");
 786   printf ("    %s\n", _("Suppress SMTP command"));
 787   printf (" %s\n", "-C, --command=STRING");
 788   printf ("    %s\n", _("SMTP command (may be used repeatedly)"));
 789   printf (" %s\n", "-R, --command=STRING");
 790   printf ("    %s\n", _("Expected response to command (may be used repeatedly)"));
 791   printf (" %s\n", "-f, --from=STRING");
 792   printf ("    %s\n", _("FROM-address to include in MAIL command, required by Exchange 2000")),
 793 #ifdef HAVE_SSL
 794   printf (" %s\n", "-D, --certificate=INTEGER");
 795   printf ("    %s\n", _("Minimum number of days a certificate has to be valid."));
 796   printf (" %s\n", "-S, --starttls");
 797   printf ("    %s\n", _("Use STARTTLS for the connection."));
 798 #endif
 799
 800         printf (" %s\n", "-A, --authtype=STRING");
 801   printf ("    %s\n", _("SMTP AUTH type to check (default none, only LOGIN supported)"));
 802   printf (" %s\n", "-U, --authuser=STRING");
 803   printf ("    %s\n", _("SMTP AUTH username"));
 804   printf (" %s\n", "-P, --authpass=STRING");
 805   printf ("    %s\n", _("SMTP AUTH password"));
 806
 807         printf (_(UT_WARN_CRIT));
 808
 809         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 810
 811         printf (_(UT_VERBOSE));
 812
 813         printf("\n");
 814         printf ("%s\n", _("Successul connects return STATE_OK, refusals and timeouts return"));
 815   printf ("%s\n", _("STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful"));
 816   printf ("%s\n", _("connects, but incorrect reponse messages from the host result in"));
 817   printf ("%s\n", _("STATE_WARNING return values."));
 818
 819 #ifdef NP_EXTRA_OPTS
 820   printf ("\n");
 821   printf ("%s\n", _("Notes:"));
 822   printf (_(UT_EXTRA_OPTS_NOTES));
 823 #endif
 824
 825         printf (_(UT_SUPPORT));
 826 }
 827
 828
 829
 830 void
 831 print_usage (void)
 832 {
 833   printf (_("Usage:"));
 834         printf ("%s -H host [-p port] [-e expect] [-C command] [-f from addr]", progname);
 835   printf ("[-A authtype -U authuser -P authpass] [-w warn] [-c crit] [-t timeout]\n");
 836   printf ("[-S] [-D days] [-n] [-v] [-4|-6]\n");
 837 }
 838