plugins/sslutils.c

   1 /*****************************************************************************
   2 *
   3 * Nagios plugins SSL utilities
   4 *
   5 * License: GPL
   6 * Copyright (c) 2005-2007 Nagios Plugins Development Team
   7 *
   8 * Last Modified: $Date$
   9 *
  10 * Description:
  11 *
  12 * This file contains common functions for plugins that require SSL.
  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 * $Id$
  29 *
  30 *****************************************************************************/
  31
  32 #define LOCAL_TIMEOUT_ALARM_HANDLER
  33 #include "common.h"
  34 #include "netutils.h"
  35
  36 #ifdef HAVE_SSL
  37 static SSL_CTX *c=NULL;
  38 static SSL *s=NULL;
  39 static int initialized=0;
  40
  41 int np_net_ssl_init (int sd){
  42                 if (!initialized) {
  43                         /* Initialize SSL context */
  44                         SSLeay_add_ssl_algorithms ();
  45                         SSL_load_error_strings ();
  46                         OpenSSL_add_all_algorithms ();
  47                         initialized = 1;
  48                 }
  49                 if ((c = SSL_CTX_new (SSLv23_client_method ())) == NULL) {
  50                                 printf ("%s\n", _("CRITICAL - Cannot create SSL context."));
  51                                 return STATE_CRITICAL;
  52                 }
  53                 if ((s = SSL_new (c)) != NULL){
  54                                 SSL_set_fd (s, sd);
  55                                 if (SSL_connect(s) == 1){
  56                                                 return OK;
  57                                 } else {
  58                                                 printf ("%s\n", _("CRITICAL - Cannot make SSL connection "));
  59 #  ifdef USE_OPENSSL /* XXX look into ERR_error_string */
  60                                                 ERR_print_errors_fp (stdout);
  61 #  endif /* USE_OPENSSL */
  62                                 }
  63                 } else {
  64                                 printf ("%s\n", _("CRITICAL - Cannot initiate SSL handshake."));
  65                 }
  66                 return STATE_CRITICAL;
  67 }
  68
  69 void np_net_ssl_cleanup (){
  70                 if(s){
  71                                 SSL_shutdown (s);
  72                                 SSL_free (s);
  73                                 if(c) {
  74                                         SSL_CTX_free (c);
  75                                         c=NULL;
  76                                 }
  77                                 s=NULL;
  78                 }
  79 }
  80
  81 int np_net_ssl_write(const void *buf, int num){
  82         return SSL_write(s, buf, num);
  83 }
  84
  85 int np_net_ssl_read(void *buf, int num){
  86         return SSL_read(s, buf, num);
  87 }
  88
  89 int np_net_ssl_check_cert(int days_till_exp){
  90 #  ifdef USE_OPENSSL
  91         X509 *certificate=NULL;
  92         ASN1_STRING *tm;
  93         int offset;
  94         struct tm stamp;
  95         int days_left;
  96         char timestamp[17] = "";
  97
  98         certificate=SSL_get_peer_certificate(s);
  99         if(! certificate){
 100                 printf ("%s\n",_("CRITICAL - Cannot retrieve server certificate."));
 101                 return STATE_CRITICAL;
 102         }
 103
 104         /* Retrieve timestamp of certificate */
 105         tm = X509_get_notAfter (certificate);
 106
 107         /* Generate tm structure to process timestamp */
 108         if (tm->type == V_ASN1_UTCTIME) {
 109                 if (tm->length < 10) {
 110                         printf ("%s\n", _("CRITICAL - Wrong time format in certificate."));
 111                         return STATE_CRITICAL;
 112                 } else {
 113                         stamp.tm_year = (tm->data[0] - '0') * 10 + (tm->data[1] - '0');
 114                         if (stamp.tm_year < 50)
 115                                 stamp.tm_year += 100;
 116                         offset = 0;
 117                 }
 118         } else {
 119                 if (tm->length < 12) {
 120                         printf ("%s\n", _("CRITICAL - Wrong time format in certificate."));
 121                         return STATE_CRITICAL;
 122                 } else {
 123                         stamp.tm_year =
 124                                 (tm->data[0] - '0') * 1000 + (tm->data[1] - '0') * 100 +
 125                                 (tm->data[2] - '0') * 10 + (tm->data[3] - '0');
 126                         stamp.tm_year -= 1900;
 127                         offset = 2;
 128                 }
 129         }
 130         stamp.tm_mon =
 131                 (tm->data[2 + offset] - '0') * 10 + (tm->data[3 + offset] - '0') - 1;
 132         stamp.tm_mday =
 133                 (tm->data[4 + offset] - '0') * 10 + (tm->data[5 + offset] - '0');
 134         stamp.tm_hour =
 135                 (tm->data[6 + offset] - '0') * 10 + (tm->data[7 + offset] - '0');
 136         stamp.tm_min =
 137                 (tm->data[8 + offset] - '0') * 10 + (tm->data[9 + offset] - '0');
 138         stamp.tm_sec = 0;
 139         stamp.tm_isdst = -1;
 140
 141         days_left = (mktime (&stamp) - time (NULL)) / 86400;
 142         snprintf
 143                 (timestamp, 17, "%02d/%02d/%04d %02d:%02d",
 144                  stamp.tm_mon + 1,
 145                  stamp.tm_mday, stamp.tm_year + 1900, stamp.tm_hour, stamp.tm_min);
 146
 147         if (days_left > 0 && days_left <= days_till_exp) {
 148                 printf (_("WARNING - Certificate expires in %d day(s) (%s).\n"), days_left, timestamp);
 149                 return STATE_WARNING;
 150         } else if (days_left < 0) {
 151                 printf (_("CRITICAL - Certificate expired on %s.\n"), timestamp);
 152                 return STATE_CRITICAL;
 153         } else if (days_left == 0) {
 154                 printf (_("WARNING - Certificate expires today (%s).\n"), timestamp);
 155                 return STATE_WARNING;
 156         }
 157
 158         printf (_("OK - Certificate will expire on %s.\n"), timestamp);
 159         X509_free (certificate);
 160         return STATE_OK;
 161 #  else /* ifndef USE_OPENSSL */
 162         printf ("%s\n", _("WARNING - Plugin does not support checking certificates."));
 163         return STATE_WARNING;
 164 #  endif /* USE_OPENSSL */
 165 }
 166
 167 #endif /* HAVE_SSL */