#!/usr/bin/env ruby
# Plugin to monitor the number of invalid access to sshd per country
#
# Require read permitions for SYSLOG
#    ref) ls -l /var/log/secure
# Require geoip rubygem
#    ref) http://geoip.rubyforge.org/
# Require GeoIP-database for searching ip or host for the country
#    ref) http://www.maxmind.com/app/geoip_country
#
# Parameters:
#       config   (required)
#       autoconf (optional - used by munin-config)
#
# $Log$
# Revision 1.0  2010/12/25 11:56:12 hirata yoshiyuki
#     released.
#
# Magick markers (optional):
#%# family=auto
#%# capabilities=autoconf
#
# config example for /etc/munin/plugin-conf.d/munin-node
#[sshd_invalid_countries_ruby]
#user root
#group root
#env.logfile /var/log/secure
#env.geoip /home/you/GeoIP.dat
#env.loadpath /usr/local/lib/ruby/gems/1.9.1/gems/geoip-0.8.8/lib/

require (ENV['loadpath'] || '') + 'geoip'

SYSLOG   = ENV['syslog'] || '/var/log/secure'
GEOIP_DB = ENV['geoip']  || '/var/www/conf/bbs/GeoIP.dat'
AWK_CMD  = 'awk \'/sshd\[.*Did not receive identification string/{print $12} ' +
                 '/sshd\[.*Failed password for (root|ROOT)/{print $11} ' +
                 '/sshd\[.*Invalid user/{print $10}a\' < ' + SYSLOG

def getInvalids
  c={}
  wholeips = `#{AWK_CMD}`.split("\n")
  uniqueips = wholeips.inject({}) do |hash, key|
    hash.include?(key) ? hash[key] += 1 : hash[key] = 1;
    hash
  end
  geoip = GeoIP.new(GEOIP_DB)
  uniqueips.each do |ip,cnt|
    begin
      country = geoip.country(ip)[5]
      c[country] = c[country] ? c[country] + cnt : cnt
    rescue
      c['Unknown'] = c['Unknown'] ? c['Unknown'] + cnt : cnt
    end
  end
  c = c.to_a.sort {|a,b| a[0] <=> b[0]}
  c
end

case ARGV[0]
when 'autoconf'
  begin
    fh = open(SYSLOG, 'r')
  rescue
    puts 'no'
    exit 0
  else
    puts 'yes'
    exit 0
  end
when 'config'
  puts 'graph_title SSHD invalid countries from ' + SYSLOG
  puts 'graph_args --base 1000 -l 0'
  puts 'graph_vlabel number of invalid access per country'
  puts 'graph_category security'
  puts 'graph_info This graph shows the countries of invalid access to sshd.'
  getInvalids.each {|k,v| puts k + '.label ' + k}
  exit 0
else
  getInvalids.each {|k,v| puts k + '.value ' + v.to_s}
end