plugins/sslutils.c

   1 /****************************************************************************
   2 *
   3 * Nagios plugins SSL utilities
   4 *
   5 * License: GPL
   6 * Copyright (c) 2005 nagios-plugins team
   7 *
   8 * Last Modified: $Date$
   9 *
  10 * Description:
  11 *
  12 * This file contains common functions for plugins that require SSL.
  13 *
  14 * License Information:
  15 *
  16 * This program is free software; you can redistribute it and/or modify
  17 * it under the terms of the GNU General Public License as published by
  18 * the Free Software Foundation; either version 2 of the License, or
  19 * (at your option) any later version.
  20 *
  21 * This program is distributed in the hope that it will be useful,
  22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24 * GNU General Public License for more details.
  25 *
  26 * You should have received a copy of the GNU General Public License
  27 * along with this program; if not, write to the Free Software
  28 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29 *
  30 * $Id$
  31 *
  32 ****************************************************************************/
  33
  34 #define LOCAL_TIMEOUT_ALARM_HANDLER
  35 #include "common.h"
  36 #include "netutils.h"
  37
  38 #ifdef HAVE_SSL
  39 static SSL_CTX *c=NULL;
  40 static SSL *s=NULL;
  41 static int initialized=0;
  42
  43 int np_net_ssl_init (int sd){
  44                 if (!initialized) {
  45                         /* Initialize SSL context */
  46                         SSLeay_add_ssl_algorithms ();
  47                         SSL_load_error_strings ();
  48                         OpenSSL_add_all_algorithms ();
  49                         initialized = 1;
  50                 }
  51                 if ((c = SSL_CTX_new (SSLv23_client_method ())) == NULL) {
  52                                 printf ("%s\n", _("CRITICAL - Cannot create SSL context."));
  53                                 return STATE_CRITICAL;
  54                 }
  55                 if ((s = SSL_new (c)) != NULL){
  56                                 SSL_set_fd (s, sd);
  57                                 if (SSL_connect(s) == 1){
  58                                                 return OK;
  59                                 } else {
  60                                                 printf ("%s\n", _("CRITICAL - Cannot make SSL connection "));
  61 #  ifdef USE_OPENSSL /* XXX look into ERR_error_string */
  62                                                 ERR_print_errors_fp (stdout);
  63 #  endif /* USE_OPENSSL */
  64                                 }
  65                 } else {
  66                                 printf ("%s\n", _("CRITICAL - Cannot initiate SSL handshake."));
  67                 }
  68                 return STATE_CRITICAL;
  69 }
  70
  71 void np_net_ssl_cleanup (){
  72                 if(s){
  73                                 SSL_shutdown (s);
  74                                 SSL_free (s);
  75                                 if(c) {
  76                                         SSL_CTX_free (c);
  77                                         c=NULL;
  78                                 }
  79                                 s=NULL;
  80                 }
  81 }
  82
  83 int np_net_ssl_write(const void *buf, int num){
  84         return SSL_write(s, buf, num);
  85 }
  86
  87 int np_net_ssl_read(void *buf, int num){
  88         return SSL_read(s, buf, num);
  89 }
  90
  91 int np_net_ssl_check_cert(int days_till_exp){
  92 #  ifdef USE_OPENSSL
  93         X509 *certificate=NULL;
  94         ASN1_STRING *tm;
  95         int offset;
  96         struct tm stamp;
  97         int days_left;
  98         char timestamp[17] = "";
  99
 100         certificate=SSL_get_peer_certificate(s);
 101         if(! certificate){
 102                 printf ("%s\n",_("CRITICAL - Cannot retrieve server certificate."));
 103                 return STATE_CRITICAL;
 104         }
 105
 106         /* Retrieve timestamp of certificate */
 107         tm = X509_get_notAfter (certificate);
 108
 109         /* Generate tm structure to process timestamp */
 110         if (tm->type == V_ASN1_UTCTIME) {
 111                 if (tm->length < 10) {
 112                         printf ("%s\n", _("CRITICAL - Wrong time format in certificate."));
 113                         return STATE_CRITICAL;
 114                 } else {
 115                         stamp.tm_year = (tm->data[0] - '0') * 10 + (tm->data[1] - '0');
 116                         if (stamp.tm_year < 50)
 117                                 stamp.tm_year += 100;
 118                         offset = 0;
 119                 }
 120         } else {
 121                 if (tm->length < 12) {
 122                         printf ("%s\n", _("CRITICAL - Wrong time format in certificate."));
 123                         return STATE_CRITICAL;
 124                 } else {
 125                         stamp.tm_year =
 126                                 (tm->data[0] - '0') * 1000 + (tm->data[1] - '0') * 100 +
 127                                 (tm->data[2] - '0') * 10 + (tm->data[3] - '0');
 128                         stamp.tm_year -= 1900;
 129                         offset = 2;
 130                 }
 131         }
 132         stamp.tm_mon =
 133                 (tm->data[2 + offset] - '0') * 10 + (tm->data[3 + offset] - '0') - 1;
 134         stamp.tm_mday =
 135                 (tm->data[4 + offset] - '0') * 10 + (tm->data[5 + offset] - '0');
 136         stamp.tm_hour =
 137                 (tm->data[6 + offset] - '0') * 10 + (tm->data[7 + offset] - '0');
 138         stamp.tm_min =
 139                 (tm->data[8 + offset] - '0') * 10 + (tm->data[9 + offset] - '0');
 140         stamp.tm_sec = 0;
 141         stamp.tm_isdst = -1;
 142
 143         days_left = (mktime (&stamp) - time (NULL)) / 86400;
 144         snprintf
 145                 (timestamp, 17, "%02d/%02d/%04d %02d:%02d",
 146                  stamp.tm_mon + 1,
 147                  stamp.tm_mday, stamp.tm_year + 1900, stamp.tm_hour, stamp.tm_min);
 148
 149         if (days_left > 0 && days_left <= days_till_exp) {
 150                 printf (_("WARNING - Certificate expires in %d day(s) (%s).\n"), days_left, timestamp);
 151                 return STATE_WARNING;
 152         } else if (days_left < 0) {
 153                 printf (_("CRITICAL - Certificate expired on %s.\n"), timestamp);
 154                 return STATE_CRITICAL;
 155         } else if (days_left == 0) {
 156                 printf (_("WARNING - Certificate expires today (%s).\n"), timestamp);
 157                 return STATE_WARNING;
 158         }
 159
 160         printf (_("OK - Certificate will expire on %s.\n"), timestamp);
 161         X509_free (certificate);
 162         return STATE_OK;
 163 #  else /* ifndef USE_OPENSSL */
 164         printf ("%s\n", _("WARNING - Plugin does not support checking certificates."));
 165         return STATE_WARNING;
 166 #  endif /* USE_OPENSSL */
 167 }
 168
 169 #endif /* HAVE_SSL */