#! /usr/bin/env ruby
# frozen_string_literal: true

#
#   check-rbl
#
# DESCRIPTION:
#   Checks if a ip is blacklisted in the common dns blacklists. You can
#   add a list
#
# OUTPUT:
#   plain text
#
# PLATFORMS:
#   Linux
#
# DEPENDENCIES:
#   gem: sensu-plugin
#   gem: dnsbl-client
#
# USAGE:
#
# NOTES:
#  A list of DNS blacklists to not be checked can be passed with -I as a
#  comma-separated list.
#
# LICENSE:
#   Copyright 2012 Sarguru Nathan  <sarguru90@gmail.com>
#   Released under the same terms as Sensu (the MIT license); see LICENSE
#   for details.
#

require 'sensu-plugin/check/cli'
require 'dnsbl/client'
require 'set'

#
# Rbl Check
#
class RblCheck < Sensu::Plugin::Check::CLI
  option :ip,
         short: '-i IPADDRESS',
         long: '--ip IPADDRESS',
         description: 'IP of the server to check'

  option :ignored_bls,
         short: '-I BLACKLISTNAME',
         long: '--ignored_bls BLACKLISTNAME',
         description: 'Comma Separated String of ignored blacklists from default list',
         default: 'null'

  option :critical_bls,
         short: '-C BLACKLISTNAME',
         long: '--critical_bls BLACKLISTNAME',
         description: 'Comma Separated String of critical blacklists from default list',
         default: 'null'

  def run
    c = DNSBL::Client.new

    if config[:ip]
      ip_add = config[:ip]
    else
      critical 'plugin failed. Required Argument -i (ip address of the client)'
    end

    if config[:ignored_bls]
      ignored_bls = config[:ignored_bls]
      ignored_bls_set = ignored_bls.split(',').to_set
    end

    if config[:critical_bls]
      critical_bls = config[:critical_bls]
      critical_bls_set = critical_bls.split(',').to_set
    end

    dnsbl_ret   = c.lookup(ip_add.to_s)
    msg_string  = ''
    criticality = 0

    # #YELLOW
    dnsbl_ret.each do |dnsbl_result|
      if dnsbl_result.meaning =~ /spam/i || dnsbl_result.meaning =~ /blacklist/i
        unless ignored_bls_set.member?(dnsbl_result.dnsbl)
          msg_string = "#{msg_string} #{dnsbl_result.dnsbl}"
        end

        criticality += 1 if critical_bls_set.member?(dnsbl_result.dnsbl)
      end
    end

    # YELLOW
    unless msg_string.empty? # rubocop:disable UnlessElse
      if criticality.positive?
        critical "#{ip_add} Blacklisted in#{msg_string}"
      else
        warning "#{ip_add} Blacklisted in#{msg_string}"
      end
    else
      msg_txt = "All is well. #{ip_add} has good reputation."
      ok msg_txt.to_s
    end
  end
end