plugins/check_smtp.c

   1 /******************************************************************************
   2
   3  This program is free software; you can redistribute it and/or modify
   4  it under the terms of the GNU General Public License as published by
   5  the Free Software Foundation; either version 2 of the License, or
   6  (at your option) any later version.
   7
   8  This program is distributed in the hope that it will be useful,
   9  but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  GNU General Public License for more details.
  12
  13  You should have received a copy of the GNU General Public License
  14  along with this program; if not, write to the Free Software
  15  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  16
  17  $Id$
  18
  19 ******************************************************************************/
  20
  21 const char *progname = "check_smtp";
  22 const char *revision = "$Revision$";
  23 const char *copyright = "2000-2004";
  24 const char *email = "nagiosplug-devel@lists.sourceforge.net";
  25
  26 #include "common.h"
  27 #include "netutils.h"
  28 #include "utils.h"
  29
  30 #ifdef HAVE_SSL_H
  31 #  include <rsa.h>
  32 #  include <crypto.h>
  33 #  include <x509.h>
  34 #  include <pem.h>
  35 #  include <ssl.h>
  36 #  include <err.h>
  37 #else
  38 #  ifdef HAVE_OPENSSL_SSL_H
  39 #    include <openssl/rsa.h>
  40 #    include <openssl/crypto.h>
  41 #    include <openssl/x509.h>
  42 #    include <openssl/pem.h>
  43 #    include <openssl/ssl.h>
  44 #    include <openssl/err.h>
  45 #  endif
  46 #endif
  47
  48 #ifdef HAVE_SSL
  49
  50 int check_cert = FALSE;
  51 int days_till_exp;
  52 SSL_CTX *ctx;
  53 SSL *ssl;
  54 X509 *server_cert;
  55 int connect_STARTTLS (void);
  56 int check_certificate (X509 **);
  57 #endif
  58
  59 enum {
  60         SMTP_PORT       = 25
  61 };
  62 #define SMTP_EXPECT "220"
  63 #define SMTP_HELO "HELO "
  64 #define SMTP_EHLO "EHLO "
  65 #define SMTP_QUIT "QUIT\r\n"
  66 #define SMTP_STARTTLS "STARTTLS\r\n"
  67
  68 #ifndef HOST_MAX_BYTES
  69 #define HOST_MAX_BYTES 255
  70 #endif
  71
  72 #define EHLO_SUPPORTS_STARTTLS 1
  73
  74 int process_arguments (int, char **);
  75 int validate_arguments (void);
  76 void print_help (void);
  77 void print_usage (void);
  78 int myrecv(void);
  79 int my_close(void);
  80
  81 #ifdef HAVE_REGEX_H
  82 #include <regex.h>
  83 char regex_expect[MAX_INPUT_BUFFER] = "";
  84 regex_t preg;
  85 regmatch_t pmatch[10];
  86 char timestamp[20] = "";
  87 char errbuf[MAX_INPUT_BUFFER];
  88 int cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
  89 int eflags = 0;
  90 int errcode, excode;
  91 #endif
  92
  93 int server_port = SMTP_PORT;
  94 char *server_address = NULL;
  95 char *server_expect = NULL;
  96 int smtp_use_dummycmd = 0;
  97 char *mail_command = NULL;
  98 char *from_arg = NULL;
  99 int ncommands=0;
 100 int command_size=0;
 101 int nresponses=0;
 102 int response_size=0;
 103 char **commands = NULL;
 104 char **responses = NULL;
 105 int warning_time = 0;
 106 int check_warning_time = FALSE;
 107 int critical_time = 0;
 108 int check_critical_time = FALSE;
 109 int verbose = 0;
 110 int use_ssl = FALSE;
 111 short use_ehlo = FALSE;
 112 short ssl_established = TRUE;
 113 char *localhostname = NULL;
 114 int sd;
 115 char buffer[MAX_INPUT_BUFFER];
 116 enum {
 117   TCP_PROTOCOL = 1,
 118   UDP_PROTOCOL = 2,
 119   MAXBUF = 1024
 120 };
 121
 122 int
 123 main (int argc, char **argv)
 124 {
 125         short supports_tls=FALSE;
 126         int n = 0;
 127         double elapsed_time;
 128         long microsec;
 129         int result = STATE_UNKNOWN;
 130         char *cmd_str = NULL;
 131         char *helocmd = NULL;
 132         struct timeval tv;
 133         struct hostent *hp;
 134
 135         setlocale (LC_ALL, "");
 136         bindtextdomain (PACKAGE, LOCALEDIR);
 137         textdomain (PACKAGE);
 138
 139         if (process_arguments (argc, argv) == ERROR)
 140                 usage4 (_("Could not parse arguments"));
 141
 142         /* initialize the HELO command with the localhostname */
 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                 hp = gethostbyname(localhostname);
 154                 if(!hp) helocmd = localhostname;
 155                 else helocmd = hp->h_name;
 156         } else {
 157                 helocmd = localhostname;
 158         }
 159         if(use_ehlo)
 160                 asprintf (&helocmd, "%s%s%s", SMTP_EHLO, helocmd, "\r\n");
 161         else
 162                 asprintf (&helocmd, "%s%s%s", SMTP_HELO, helocmd, "\r\n");
 163
 164         /* initialize the MAIL command with optional FROM command  */
 165         asprintf (&cmd_str, "%sFROM: %s%s", mail_command, from_arg, "\r\n");
 166
 167         if (verbose && smtp_use_dummycmd)
 168                 printf ("FROM CMD: %s", cmd_str);
 169
 170         /* initialize alarm signal handling */
 171         (void) signal (SIGALRM, socket_timeout_alarm_handler);
 172
 173         /* set socket timeout */
 174         (void) alarm (socket_timeout);
 175
 176         /* start timer */
 177         gettimeofday (&tv, NULL);
 178
 179         /* try to connect to the host at the given port number */
 180         result = my_tcp_connect (server_address, server_port, &sd);
 181
 182         if (result == STATE_OK) { /* we connected */
 183
 184                 /* watch for the SMTP connection string and */
 185                 /* return a WARNING status if we couldn't read any data */
 186                 if (recv (sd, buffer, MAX_INPUT_BUFFER - 1, 0) == -1) {
 187                         printf (_("recv() failed\n"));
 188                         result = STATE_WARNING;
 189                 }
 190                 else {
 191                         if (verbose)
 192                                 printf ("%s", buffer);
 193                         /* strip the buffer of carriage returns */
 194                         strip (buffer);
 195                         /* make sure we find the response we are looking for */
 196                         if (!strstr (buffer, server_expect)) {
 197                                 if (server_port == SMTP_PORT)
 198                                         printf (_("Invalid SMTP response received from host\n"));
 199                                 else
 200                                         printf (_("Invalid SMTP response received from host on port %d\n"),
 201                                                                         server_port);
 202                                 result = STATE_WARNING;
 203                         }
 204                 }
 205
 206                 /* send the HELO/EHLO command */
 207                 send(sd, helocmd, strlen(helocmd), 0);
 208
 209                 /* allow for response to helo command to reach us */
 210                 if(read (sd, buffer, MAXBUF - 1) < 0){
 211                         printf (_("recv() failed\n"));
 212                         return STATE_WARNING;
 213                 } else if(use_ehlo){
 214                         buffer[MAXBUF-1]='\0';
 215                         if(strstr(buffer, "250 STARTTLS") != NULL ||
 216                            strstr(buffer, "250-STARTTLS") != NULL){
 217                                 supports_tls=TRUE;
 218                         }
 219                 }
 220
 221                 if(use_ssl && ! supports_tls){
 222                         printf(_("WARNING - TLS not supported by server\n"));
 223                         send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
 224                         return STATE_WARNING;
 225                 }
 226
 227 #ifdef HAVE_SSL
 228                 if(use_ssl) {
 229                   /* send the STARTTLS command */
 230                   send(sd, SMTP_STARTTLS, strlen(SMTP_STARTTLS), 0);
 231
 232                   recv(sd,buffer, MAX_INPUT_BUFFER-1, 0); /* wait for it */
 233                   if (!strstr (buffer, server_expect)) {
 234                     printf (_("Server does not support STARTTLS\n"));
 235                     send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
 236                     return STATE_UNKNOWN;
 237                   }
 238                   if(connect_STARTTLS() != OK) {
 239                     printf (_("CRITICAL - Cannot create SSL context.\n"));
 240                     return STATE_CRITICAL;
 241                   } else {
 242                         ssl_established = TRUE;
 243                   }
 244                   if ( check_cert ) {
 245                     if ((server_cert = SSL_get_peer_certificate (ssl)) != NULL) {
 246                       result = check_certificate (&server_cert);
 247                       X509_free(server_cert);
 248                     }
 249                     else {
 250                       printf (_("CRITICAL - Cannot retrieve server certificate.\n"));
 251                       result = STATE_CRITICAL;
 252
 253                     }
 254                     my_close();
 255                     return result;
 256                   }
 257                 }
 258 #endif
 259
 260                 /* sendmail will syslog a "NOQUEUE" error if session does not attempt
 261                  * to do something useful. This can be prevented by giving a command
 262                  * even if syntax is illegal (MAIL requires a FROM:<...> argument)
 263                  *
 264                  * According to rfc821 you can include a null reversepath in the from command
 265                  * - but a log message is generated on the smtp server.
 266                  *
 267                  * You can disable sending mail_command with '--nocommand'
 268                  * Use the -f option to provide a FROM address
 269                  */
 270                 if (smtp_use_dummycmd) {
 271 #ifdef HAVE_SSL
 272                   if (use_ssl)
 273                     SSL_write(ssl, cmd_str, strlen(cmd_str));
 274                   else
 275 #endif
 276                   send(sd, cmd_str, strlen(cmd_str), 0);
 277                   myrecv();
 278                   if (verbose)
 279                     printf("%s", buffer);
 280                 }
 281
 282                 while (n < ncommands) {
 283                         asprintf (&cmd_str, "%s%s", commands[n], "\r\n");
 284 #ifdef HAVE_SSL
 285                         if (use_ssl)
 286                           SSL_write(ssl,cmd_str, strlen(cmd_str));
 287                         else
 288 #endif
 289                         send(sd, cmd_str, strlen(cmd_str), 0);
 290                         myrecv();
 291                         if (verbose)
 292                                 printf("%s", buffer);
 293                         strip (buffer);
 294                         if (n < nresponses) {
 295 #ifdef HAVE_REGEX_H
 296                                 cflags |= REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
 297                                 errcode = regcomp (&preg, responses[n], cflags);
 298                                 if (errcode != 0) {
 299                                         regerror (errcode, &preg, errbuf, MAX_INPUT_BUFFER);
 300                                         printf (_("Could Not Compile Regular Expression"));
 301                                         return ERROR;
 302                                 }
 303                                 excode = regexec (&preg, buffer, 10, pmatch, eflags);
 304                                 if (excode == 0) {
 305                                         result = STATE_OK;
 306                                 }
 307                                 else if (excode == REG_NOMATCH) {
 308                                         result = STATE_WARNING;
 309                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 310                                 }
 311                                 else {
 312                                         regerror (excode, &preg, errbuf, MAX_INPUT_BUFFER);
 313                                         printf (_("Execute Error: %s\n"), errbuf);
 314                                         result = STATE_UNKNOWN;
 315                                 }
 316 #else
 317                                 if (strstr(buffer, responses[n])!=buffer) {
 318                                         result = STATE_WARNING;
 319                                         printf (_("SMTP %s - Invalid response '%s' to command '%s'\n"), state_text (result), buffer, commands[n]);
 320                                 }
 321 #endif
 322                         }
 323                         n++;
 324                 }
 325
 326                 /* tell the server we're done */
 327 #ifdef HAVE_SSL
 328                 if (use_ssl)
 329                   SSL_write(ssl,SMTP_QUIT, strlen (SMTP_QUIT));
 330                 else
 331 #endif
 332                 send (sd, SMTP_QUIT, strlen (SMTP_QUIT), 0);
 333
 334                 /* finally close the connection */
 335                 close (sd);
 336         }
 337
 338         /* reset the alarm */
 339         alarm (0);
 340
 341         microsec = deltime (tv);
 342         elapsed_time = (double)microsec / 1.0e6;
 343
 344         if (result == STATE_OK) {
 345                 if (check_critical_time && elapsed_time > (double) critical_time)
 346                         result = STATE_CRITICAL;
 347                 else if (check_warning_time && elapsed_time > (double) warning_time)
 348                         result = STATE_WARNING;
 349         }
 350
 351         printf (_("SMTP %s - %.3f sec. response time%s%s|%s\n"),
 352                 state_text (result), elapsed_time,
 353           verbose?", ":"", verbose?buffer:"",
 354                 fperfdata ("time", elapsed_time, "s",
 355                           (int)check_warning_time, warning_time,
 356                           (int)check_critical_time, critical_time,
 357                           TRUE, 0, FALSE, 0));
 358
 359         return result;
 360 }
 361
 362
 363
 364 /* process command-line arguments */
 365 int
 366 process_arguments (int argc, char **argv)
 367 {
 368         int c;
 369
 370         int option = 0;
 371         static struct option longopts[] = {
 372                 {"hostname", required_argument, 0, 'H'},
 373                 {"expect", required_argument, 0, 'e'},
 374                 {"critical", required_argument, 0, 'c'},
 375                 {"warning", required_argument, 0, 'w'},
 376                 {"timeout", required_argument, 0, 't'},
 377                 {"port", required_argument, 0, 'p'},
 378                 {"from", required_argument, 0, 'f'},
 379                 {"fqdn", required_argument, 0, 'F'},
 380                 {"command", required_argument, 0, 'C'},
 381                 {"response", required_argument, 0, 'R'},
 382                 {"nocommand", required_argument, 0, 'n'},
 383                 {"verbose", no_argument, 0, 'v'},
 384                 {"version", no_argument, 0, 'V'},
 385                 {"use-ipv4", no_argument, 0, '4'},
 386                 {"use-ipv6", no_argument, 0, '6'},
 387                 {"help", no_argument, 0, 'h'},
 388                 {"starttls",no_argument,0,'S'},
 389                 {"certificate",required_argument,0,'D'},
 390                 {0, 0, 0, 0}
 391         };
 392
 393         if (argc < 2)
 394                 return ERROR;
 395
 396         for (c = 1; c < argc; c++) {
 397                 if (strcmp ("-to", argv[c]) == 0)
 398                         strcpy (argv[c], "-t");
 399                 else if (strcmp ("-wt", argv[c]) == 0)
 400                         strcpy (argv[c], "-w");
 401                 else if (strcmp ("-ct", argv[c]) == 0)
 402                         strcpy (argv[c], "-c");
 403         }
 404
 405         while (1) {
 406                 c = getopt_long (argc, argv, "+hVv46t:p:f:e:c:w:H:C:R:SD:F:",
 407                                  longopts, &option);
 408
 409                 if (c == -1 || c == EOF)
 410                         break;
 411
 412                 switch (c) {
 413                 case 'H':                                                                       /* hostname */
 414                         if (is_host (optarg)) {
 415                                 server_address = optarg;
 416                         }
 417                         else {
 418                                 usage2 (_("Invalid hostname/address"), optarg);
 419                         }
 420                         break;
 421                 case 'p':                                                                       /* port */
 422                         if (is_intpos (optarg))
 423                                 server_port = atoi (optarg);
 424                         else
 425                                 usage4 (_("Port must be a positive integer"));
 426                         break;
 427                 case 'F':
 428                 /* localhostname */
 429                         localhostname = strdup(optarg);
 430                         break;
 431                 case 'f':                                                                       /* from argument */
 432                         from_arg = optarg;
 433                         smtp_use_dummycmd = 1;
 434                         break;
 435                 case 'e':                                                                       /* server expect string on 220  */
 436                         server_expect = optarg;
 437                         break;
 438                 case 'C':                                                                       /* commands  */
 439                         if (ncommands >= command_size) {
 440                                 commands = realloc (commands, command_size+8);
 441                                 if (commands == NULL)
 442                                         die (STATE_UNKNOWN,
 443                                              _("Could not realloc() units [%d]\n"), ncommands);
 444                         }
 445                         commands[ncommands] = optarg;
 446                         ncommands++;
 447                         break;
 448                 case 'R':                                                                       /* server responses */
 449                         if (nresponses >= response_size) {
 450                                 responses = realloc (responses, response_size+8);
 451                                 if (responses == NULL)
 452                                         die (STATE_UNKNOWN,
 453                                              _("Could not realloc() units [%d]\n"), nresponses);
 454                         }
 455                         responses[nresponses] = optarg;
 456                         nresponses++;
 457                         break;
 458                 case 'c':                                                                       /* critical time threshold */
 459                         if (is_intnonneg (optarg)) {
 460                                 critical_time = atoi (optarg);
 461                                 check_critical_time = TRUE;
 462                         }
 463                         else {
 464                                 usage4 (_("Critical time must be a positive integer"));
 465                         }
 466                         break;
 467                 case 'w':                                                                       /* warning time threshold */
 468                         if (is_intnonneg (optarg)) {
 469                                 warning_time = atoi (optarg);
 470                                 check_warning_time = TRUE;
 471                         }
 472                         else {
 473                                 usage4 (_("Warning time must be a positive integer"));
 474                         }
 475                         break;
 476                 case 'v':                                                                       /* verbose */
 477                         verbose++;
 478                         break;
 479                 case 't':                                                                       /* timeout */
 480                         if (is_intnonneg (optarg)) {
 481                                 socket_timeout = atoi (optarg);
 482                         }
 483                         else {
 484                                 usage4 (_("Timeout interval must be a positive integer"));
 485                         }
 486                         break;
 487                 case 'S':
 488                 /* starttls */
 489                         use_ssl = TRUE;
 490                         use_ehlo = TRUE;
 491                         break;
 492                 case 'D':
 493                 /* Check SSL cert validity */
 494 #ifdef HAVE_SSL
 495                         if (!is_intnonneg (optarg))
 496                                 usage2 ("Invalid certificate expiration period",optarg);
 497                                 days_till_exp = atoi (optarg);
 498                                 check_cert = TRUE;
 499 #else
 500                                 usage (_("SSL support not available - install OpenSSL and recompile"));
 501 #endif
 502                         break;
 503                 case '4':
 504                         address_family = AF_INET;
 505                         break;
 506                 case '6':
 507 #ifdef USE_IPV6
 508                         address_family = AF_INET6;
 509 #else
 510                         usage4 (_("IPv6 support not available"));
 511 #endif
 512                         break;
 513                 case 'V':                                                                       /* version */
 514                         print_revision (progname, revision);
 515                         exit (STATE_OK);
 516                 case 'h':                                                                       /* help */
 517                         print_help ();
 518                         exit (STATE_OK);
 519                 case '?':                                                                       /* help */
 520                         usage2 (_("Unknown argument"), optarg);
 521                 }
 522         }
 523
 524         c = optind;
 525         if (server_address == NULL) {
 526                 if (argv[c]) {
 527                         if (is_host (argv[c]))
 528                                 server_address = argv[c];
 529                         else
 530                                 usage2 (_("Invalid hostname/address"), argv[c]);
 531                 }
 532                 else {
 533                         asprintf (&server_address, "127.0.0.1");
 534                 }
 535         }
 536
 537         if (server_expect == NULL)
 538                 server_expect = strdup (SMTP_EXPECT);
 539
 540         if (mail_command == NULL)
 541                 mail_command = strdup("MAIL ");
 542
 543         if (from_arg==NULL)
 544                 from_arg = strdup(" ");
 545
 546         return validate_arguments ();
 547 }
 548
 549
 550
 551 int
 552 validate_arguments (void)
 553 {
 554         return OK;
 555 }
 556
 557
 558
 559 void
 560 print_help (void)
 561 {
 562         char *myport;
 563         asprintf (&myport, "%d", SMTP_PORT);
 564
 565         print_revision (progname, revision);
 566
 567         printf ("Copyright (c) 1999-2001 Ethan Galstad <nagios@nagios.org>\n");
 568         printf (COPYRIGHT, copyright, email);
 569
 570         printf(_("This plugin will attempt to open an SMTP connection with the host.\n\n"));
 571
 572         print_usage ();
 573
 574         printf (_(UT_HELP_VRSN));
 575
 576         printf (_(UT_HOST_PORT), 'p', myport);
 577
 578         printf (_(UT_IPv46));
 579
 580         printf (_("\
 581  -e, --expect=STRING\n\
 582    String to expect in first line of server response (default: '%s')\n\
 583  -n, nocommand\n\
 584    Suppress SMTP command\n\
 585  -C, --command=STRING\n\
 586    SMTP command (may be used repeatedly)\n\
 587  -R, --command=STRING\n\
 588    Expected response to command (may be used repeatedly)\n\
 589  -f, --from=STRING\n\
 590    FROM-address to include in MAIL command, required by Exchange 2000\n"),
 591                 SMTP_EXPECT);
 592 #ifdef HAVE_SSL
 593         printf (_("\
 594  -D, --certificate=INTEGER\n\
 595     Minimum number of days a certificate has to be valid.\n\
 596  -S, --starttls\n\
 597     Use STARTTLS for the connection.\n"));
 598 #endif
 599
 600         printf (_(UT_WARN_CRIT));
 601
 602         printf (_(UT_TIMEOUT), DEFAULT_SOCKET_TIMEOUT);
 603
 604         printf (_(UT_VERBOSE));
 605
 606         printf(_("\n\
 607 Successul connects return STATE_OK, refusals and timeouts return\n\
 608 STATE_CRITICAL, other errors return STATE_UNKNOWN.  Successful\n\
 609 connects, but incorrect reponse messages from the host result in\n\
 610 STATE_WARNING return values.\n"));
 611
 612         printf (_(UT_SUPPORT));
 613 }
 614
 615
 616
 617 void
 618 print_usage (void)
 619 {
 620         printf ("\
 621 Usage: %s -H host [-p port] [-e expect] [-C command] [-f from addr]\n\
 622                   [-w warn] [-c crit] [-t timeout] [-S] [-D days] [-n] [-v] [-4|-6]\n", progname);
 623 }
 624
 625 #ifdef HAVE_SSL
 626 int
 627 connect_STARTTLS (void)
 628 {
 629   SSL_METHOD *meth;
 630
 631   /* Initialize SSL context */
 632   SSLeay_add_ssl_algorithms ();
 633   meth = SSLv23_client_method ();
 634   SSL_load_error_strings ();
 635   if ((ctx = SSL_CTX_new (meth)) == NULL)
 636     {
 637       printf(_("CRITICAL - Cannot create SSL context.\n"));
 638       return STATE_CRITICAL;
 639     }
 640   /* do the SSL handshake */
 641   if ((ssl = SSL_new (ctx)) != NULL)
 642     {
 643       SSL_set_fd (ssl, sd);
 644       /* original version checked for -1
 645          I look for success instead (1) */
 646       if (SSL_connect (ssl) == 1)
 647         return OK;
 648       ERR_print_errors_fp (stderr);
 649     }
 650   else
 651     {
 652       printf (_("CRITICAL - Cannot initiate SSL handshake.\n"));
 653     }
 654   my_close();
 655
 656   return STATE_CRITICAL;
 657 }
 658
 659 int
 660 check_certificate (X509 ** certificate)
 661 {
 662   ASN1_STRING *tm;
 663   int offset;
 664   struct tm stamp;
 665   int days_left;
 666
 667   /* Retrieve timestamp of certificate */
 668   tm = X509_get_notAfter (*certificate);
 669
 670   /* Generate tm structure to process timestamp */
 671   if (tm->type == V_ASN1_UTCTIME) {
 672     if (tm->length < 10) {
 673       printf (_("CRITICAL - Wrong time format in certificate.\n"));
 674       return STATE_CRITICAL;
 675     }
 676     else {
 677       stamp.tm_year = (tm->data[0] - '0') * 10 + (tm->data[1] - '0');
 678       if (stamp.tm_year < 50)
 679         stamp.tm_year += 100;
 680       offset = 0;
 681     }
 682   }
 683   else {
 684     if (tm->length < 12) {
 685       printf (_("CRITICAL - Wrong time format in certificate.\n"));
 686       return STATE_CRITICAL;
 687     }
 688     else {
 689       stamp.tm_year =
 690         (tm->data[0] - '0') * 1000 + (tm->data[1] - '0') * 100 +
 691         (tm->data[2] - '0') * 10 + (tm->data[3] - '0');
 692       stamp.tm_year -= 1900;
 693       offset = 2;
 694     }
 695   }
 696   stamp.tm_mon =
 697     (tm->data[2 + offset] - '0') * 10 + (tm->data[3 + offset] - '0') - 1;
 698   stamp.tm_mday =
 699     (tm->data[4 + offset] - '0') * 10 + (tm->data[5 + offset] - '0');
 700   stamp.tm_hour =
 701     (tm->data[6 + offset] - '0') * 10 + (tm->data[7 + offset] - '0');
 702   stamp.tm_min =
 703     (tm->data[8 + offset] - '0') * 10 + (tm->data[9 + offset] - '0');
 704   stamp.tm_sec = 0;
 705   stamp.tm_isdst = -1;
 706
 707   days_left = (mktime (&stamp) - time (NULL)) / 86400;
 708   snprintf
 709     (timestamp, sizeof(timestamp), "%02d/%02d/%04d %02d:%02d",
 710      stamp.tm_mon + 1,
 711      stamp.tm_mday, stamp.tm_year + 1900, stamp.tm_hour, stamp.tm_min);
 712
 713   if (days_left > 0 && days_left <= days_till_exp) {
 714     printf ("Certificate expires in %d day(s) (%s).\n", days_left, timestamp);
 715     return STATE_WARNING;
 716   }
 717   if (days_left < 0) {
 718     printf ("Certificate expired on %s.\n", timestamp);
 719     return STATE_CRITICAL;
 720   }
 721
 722   if (days_left == 0) {
 723     printf ("Certificate expires today (%s).\n", timestamp);
 724     return STATE_WARNING;
 725   }
 726
 727   printf ("Certificate will expire on %s.\n", timestamp);
 728
 729   return STATE_OK;
 730 }
 731 #endif
 732
 733 int
 734 myrecv (void)
 735 {
 736   int i;
 737
 738 #ifdef HAVE_SSL
 739   if (use_ssl) {
 740     i = SSL_read (ssl, buffer, MAXBUF - 1);
 741   }
 742   else {
 743 #endif
 744     i = read (sd, buffer, MAXBUF - 1);
 745 #ifdef HAVE_SSL
 746   }
 747 #endif
 748   return i;
 749 }
 750
 751 int
 752 my_close (void)
 753 {
 754 #ifdef HAVE_SSL
 755   if (use_ssl == TRUE && ssl_established == TRUE) {
 756     SSL_shutdown (ssl);
 757     SSL_free (ssl);
 758     SSL_CTX_free (ctx);
 759     return 0;
 760   }
 761   else {
 762 #endif
 763     return close(sd);
 764 #ifdef HAVE_SSL
 765   }
 766 #endif
 767 }