(c) Matteo Corti, ETH Zurich, 2007-2012
 (c) Matteo Corti, 2007-2016

  see AUTHORS for the complete list of contributors

check_ssl_cert

A Nagios plugin to check an X.509 certificate:
 - checks if the server is running and delivers a valid certificate
 - checks if the CA matches a given pattern
 - checks the validity

Usage:
======

check_ssl_cert -H host [OPTIONS]

Arguments:
   -H,--host host            server

Options:
   -A,--noauth               ignore authority warnings (expiration only)
      --altnames             matches the pattern specified in -n with alternate
                             names too
   -C,--clientcert path      use client certificate to authenticate
      --clientpass phrase    set passphrase for client certificate.
   -c,--critical days        minimum number of days a certificate has to be valid
                             to issue a critical status
   -e,--email address        pattern to match the email address contained in the
                             certificate
   -f,--file file            local file path (works with -H localhost only)
   -h,--help,-?              this help message
      --long-output list     append the specified comma separated (no spaces) list
                             of attributes to the plugin output on additional lines.
                             Valid attributes are:
                               enddate, startdate, subject, issuer, modulus, serial,
                               hash, email, ocsp_uri and fingerprint.
                             'all' will include all the available attributes.
   -i,--issuer issuer           pattern to match the issuer of the certificate
   -L,--check-ssl-labs grade SSL Labs assestment
                             (please check https://www.ssllabs.com/about/terms.html)
   -n,--cn name              pattern to match the CN of the certificate
   -N,--host-cn              match CN with the host name
      --ocsp                 check revocation via OCSP
   -o,--org org              pattern to match the organization of the certificate
      --openssl path         path of the openssl binary to be used
   -p,--port port            TCP port
   -P,--protocol protocol    use the specific protocol {http|smtp|pop3|imap|ftp|xmpp}
                             http:               default
                             smtp,pop3,imap,ftp: switch to TLS
   -s,--selfsigned           allows self-signed certificates
      --serial serialnum     pattern to match the serial number
   -S,--ssl version          force SSL version (2,3)
   -r,--rootcert path        root certificate or directory to be used for
                             certificate validation
   -t,--timeout              seconds timeout after the specified time
                             (defaults to 15 seconds)
      --temp dir             directory where to store the temporary files
      --tls1                 force TLS version 1
   -v,--verbose              verbose output
   -V,--version              version
   -w,--warning days         minimum number of days a certificate has to be valid
                             to issue a warning status

Expect:
=======

check_ssl_cert requires 'expect' to enable timouts. If expect is not
present on your system timeouts will be disabled.

See: http://en.wikipedia.org/wiki/Expect

Perl and Date::Parse:
=====================

If perl and Date::Parse are available the plugin will also compute for
how many days the certificate will be valid and put the information in
the performance data. If perl or Date::Parse are not available the
information will not be available.

Virtual servers:
================

check_ssl_client supports the servername TLS extension in ClientHello
if the installed openssl version provides it. This is needed if you
are checking a machine with virtual hosts.

SSL Labs:
=========

If -L or --check-ssl-labs are specified the plugin will check the
cached status using the SSL Labs Assessment API (see
https://www.ssllabs.com/about/terms.html).

The plugin will ask for a cached result (maximum age 1 day) to avoid
to many checks. The first time you issue the check you could therefore
get an outdated result.

Notes:
======

the root certificate corresponding to the checked certificate must be
available to openssl or specified with the '-r cabundle' or
'--rootcert cabundle' option, where cabundle is either a file for -CAfile
or a directory for -CApath.

On Mac OS X the root certificates bundle is stored in the Keychain and
openssl will complain with:

   verification error: unable to get local issuer certificate

The bundle can be extracted with:

$ sudo security find-certificate -a \
  -p /System/Library/Keychains/SystemRootCertificates.keychain > cabundle.crt

Bugs:
=====

Report bugs to https://github.com/matteocorti/check_ssl_cert/issues