mirror of
https://github.com/munin-monitoring/contrib.git
synced 2025-07-21 18:41:03 +00:00
206 lines
6.1 KiB
Bash
Executable file
206 lines
6.1 KiB
Bash
Executable file
#!/bin/sh -u
|
|
# -*- sh -*-
|
|
# shellcheck disable=SC2039
|
|
|
|
: << =cut
|
|
|
|
=head1 NAME
|
|
|
|
ssl-certificate-expiry - Plugin to monitor Certificate expiration on multiple services and ports
|
|
|
|
=head1 CONFIGURATION
|
|
|
|
[ssl-certificate-expiry]
|
|
env.services www.service.tld blah.example.net_PORT foo.example.net_PORT_STARTTLS
|
|
|
|
PORT is the TCP port number
|
|
STARTTLS is passed to openssl as "-starttls" argument. Useful for services like SMTP or IMAP implementing StartTLS.
|
|
Current known values are ftp, imap, pop3 and smtp
|
|
PORT is mandatory if STARTTLS is used.
|
|
|
|
To set warning and critical levels do like this:
|
|
|
|
[ssl-certificate-expiry]
|
|
env.services ...
|
|
env.warning 30:
|
|
|
|
Alternatively, if you want to monitor hosts separately, you can create multiple symlinks named as follows.
|
|
|
|
ssl-certificate-expiry_HOST_PORT
|
|
|
|
For example:
|
|
|
|
ssl-certificate-expiry_www.example.net
|
|
ssl-certificate-expiry_www.example.org_443
|
|
ssl-certificate-expiry_192.0.2.42_636
|
|
ssl-certificate-expiry_2001:0DB8::badc:0fee_485
|
|
ssl-certificate-expiry_mail.example.net_25_smtp
|
|
|
|
=head2 Cron setup
|
|
|
|
To avoid having to run the SSL checks during the munin-update, it is possible
|
|
to run it from cron, and save a cachefile to be read during the update, This is
|
|
particularly useful when checking a large number of certificates, or when some
|
|
of the hosts are slow.
|
|
|
|
To do so, add a cron job running the plugin with cron as the argument:
|
|
|
|
<minute> * * * <user> /usr/sbin/munin-run/ssl-certificate-expiry cron
|
|
|
|
<user> should be the user that has write permission to the MUNIN_PLUGSTATE.
|
|
<minute> should be a number between 0 and 59 when the check should run every hour.
|
|
|
|
If, for any reason, the cron script stops running, the script will revert to
|
|
uncached updates after the cache file is older than an hour.
|
|
|
|
=head1 AUTHORS
|
|
|
|
* Pactrick Domack (ssl_)
|
|
* Olivier Mehani (ssl-certificate-expiry)
|
|
* Martin Schobert (check for intermediate certs)
|
|
|
|
* Copyright (C) 2013 Patrick Domack <patrickdk@patrickdk.com>
|
|
* Copyright (C) 2017, 2019 Olivier Mehani <shtrom+munin@ssji.net>
|
|
* Copyright (C) 2020 Martin Schobert <martin@schobert.cc>
|
|
|
|
=head1 LICENSE
|
|
|
|
=cut
|
|
|
|
# shellcheck disable=SC1090
|
|
. "${MUNIN_LIBDIR}/plugins/plugin.sh"
|
|
|
|
if [ "${MUNIN_DEBUG:-0}" = 1 ]; then
|
|
set -x
|
|
fi
|
|
|
|
HOSTPORT=${0##*ssl-certificate-expiry_}
|
|
CACHEFILE="${MUNIN_PLUGSTATE}/$(basename "${0}").cache"
|
|
|
|
if [ "${HOSTPORT}" != "${0}" ] \
|
|
&& [ -n "${HOSTPORT}" ]; then
|
|
services="${HOSTPORT}"
|
|
fi
|
|
|
|
|
|
# Read data including a certificate from stdin and output the (fractional) number of days left
|
|
# until the expiry of this certificate. The output is empty if parsing failed.
|
|
parse_valid_days_from_certificate() {
|
|
local input_data
|
|
local valid_until_string
|
|
local valid_until_epoch
|
|
local now_epoch
|
|
local input_data
|
|
input_data=$(cat)
|
|
|
|
if echo "$input_data" | grep -q -- "-----BEGIN CERTIFICATE-----"; then
|
|
valid_until_string=$(echo "$input_data" | openssl x509 -noout -enddate \
|
|
| grep "^notAfter=" | cut -f 2 -d "=")
|
|
if [ -n "$valid_until_string" ]; then
|
|
# FreeBSD requires special arguments for "date"
|
|
if uname | grep -q ^FreeBSD; then
|
|
valid_until_epoch=$(date -j -f '%b %e %T %Y %Z' "$valid_until_string" +%s)
|
|
now_epoch=$(date -j +%s)
|
|
else
|
|
valid_until_epoch=$(date --date="$valid_until_string" +%s)
|
|
now_epoch=$(date +%s)
|
|
fi
|
|
if [ -n "$valid_until_epoch" ]; then
|
|
# calculate the number of days left
|
|
echo "$valid_until_epoch" "$now_epoch" | awk '{ print(($1 - $2) / (24 * 3600)); }'
|
|
fi
|
|
fi
|
|
fi
|
|
}
|
|
|
|
|
|
print_expire_days() {
|
|
local host="$1"
|
|
local port="$2"
|
|
local starttls="$3"
|
|
|
|
# Wrap IPv6 addresses in square brackets
|
|
echo "$host" | grep -q ':' && host="[$host]"
|
|
|
|
local s_client_args=
|
|
[ -n "$starttls" ] && s_client_args="-starttls $starttls"
|
|
|
|
# We extract and check the server certificate,
|
|
# but the end date also depends on intermediate certs. Therefore
|
|
# we want to check intermediate certs as well.
|
|
#
|
|
# The following cryptic lines do:
|
|
# - invoke openssl and connect to a port
|
|
# - print certs, not only the server cert
|
|
# - extract each certificate as a single line
|
|
# - pipe each cert to the parse_valid_days_from_certificate
|
|
# function, which basically is 'openssl x509 -enddate'
|
|
# - get a list of the parse_valid_days_from_certificate
|
|
# results and sort them
|
|
|
|
# shellcheck disable=SC2086
|
|
echo "" | openssl s_client \
|
|
-servername "$host" -connect "${host}:${port}" \
|
|
-showcerts \
|
|
$s_client_args 2>/dev/null | \
|
|
awk '{
|
|
if ($0 == "-----BEGIN CERTIFICATE-----") cert=""
|
|
else if ($0 == "-----END CERTIFICATE-----") print cert
|
|
else cert=cert$0
|
|
}' | \
|
|
while read -r CERT; do
|
|
(printf '\n-----BEGIN CERTIFICATE-----\n%s\n-----END CERTIFICATE-----\n' "$CERT") | \
|
|
parse_valid_days_from_certificate
|
|
done | sort -n | head -n 1
|
|
|
|
}
|
|
|
|
main() {
|
|
for service in $services; do
|
|
if echo "$service" | grep -q "_"; then
|
|
host=$(echo "$service" | cut -f 1 -d "_")
|
|
port=$(echo "$service" | cut -f 2 -d "_")
|
|
starttls=$(echo "$service" | cut -f 3 -d "_")
|
|
else
|
|
host=$service
|
|
port=443
|
|
starttls=""
|
|
fi
|
|
fieldname="$(clean_fieldname "$service")"
|
|
valid_days=$(print_expire_days "$host" "$port" "$starttls")
|
|
[ -z "$valid_days" ] && valid_days="U"
|
|
printf "%s.value %s\\n" "$fieldname" "$valid_days"
|
|
echo "${fieldname}.extinfo Last checked: $(date)"
|
|
done
|
|
}
|
|
|
|
case ${1:-} in
|
|
config)
|
|
echo "graph_title SSL Certificates Expiration"
|
|
echo 'graph_args --base 1000'
|
|
echo 'graph_vlabel days left'
|
|
echo 'graph_category security'
|
|
echo "graph_info This graph shows the numbers of days before certificate expiry"
|
|
for service in $services; do
|
|
fieldname=$(clean_fieldname "$service")
|
|
echo "${fieldname}.label $(echo "${service}" | sed 's/_/:/')"
|
|
print_thresholds "${fieldname}" warning critical
|
|
done
|
|
|
|
exit 0
|
|
;;
|
|
cron)
|
|
UPDATE="$(main)"
|
|
echo "${UPDATE}" > "${CACHEFILE}"
|
|
chmod 0644 "${CACHEFILE}"
|
|
|
|
exit 0
|
|
;;
|
|
esac
|
|
|
|
if [ -n "$(find "${CACHEFILE}" -mmin -60 2>/dev/null)" ]; then
|
|
cat "${CACHEFILE}"
|
|
exit 0
|
|
fi
|
|
|
|
main
|