lan_scanner.rb in lan_scanner-0.0.4

- old
+ new
@@ -1,104 +1,116 @@
-
-require 'socket'
-require 'ostruct'
-require 'tty-which'
-require 'tmpdir'
-require 'nokogiri'
-
-
-require_relative 'lan_scanner/device'
-require_relative 'lan_scanner/version'
-
-module LanScanner
-
-  # @return [Array<LanScanner::Device>] list of devices
-  def self.scan_devices(network: nil)
-    _ensure_nmap_available
-    if network.nil?
-      network = my_networks
-    end
-    network = [network] unless network.is_a? Array
-    sn_xml_results = []
-    tmp_file = "#{Dir.tmpdir}/nmap_scan_#{Random.random_number}.xml"
-    # first we do an -sL scan, which also receives addresses from router/network cache,
-    # that are not found by -sn scan when scanning for the complete network, but are found
-    # with -sn scan, when scanning for this addresses explicitly
-    #
-    # so after this scan we scan for this addresses beneath the networks with -sn
-    sl_xml_results = []
-    network.each do |n|
-      ['-sL'].each do |nmap_type|
-        `nmap #{nmap_type} #{n} -oX "#{tmp_file}"`
-        sl_xml_results.push File.read tmp_file
-        File.delete tmp_file
-      end
-    end
-    # here we scan for the received ip addresses from network cache
-    sl_ips = _parse_nmap_xml sl_xml_results
-    `nmap -sn #{sl_ips.map(&:remote_address).join(' ')} -oX "#{tmp_file}"`
-    sn_xml_results.push File.read tmp_file
-    # here we ping the networks (fast ping which does not detect all)
-    network.each do |n|
-      ['-sn'].each do |nmap_type|
-        `nmap #{nmap_type} #{n} -oX "#{tmp_file}"`
-        sn_xml_results.push File.read tmp_file
-        File.delete tmp_file
-      end
-    end
-    _parse_nmap_xml sn_xml_results
-  end
-
-  # get states of given addresses
-  def self.scan_device_states addresses
-    addresses = [addresses] unless addresses.is_a? Array
-    tmp_file = "#{Dir.tmpdir}/nmap_scan_#{Random.random_number}.xml"
-    `nmap -sn #{addresses.join(' ')} -oX "#{tmp_file}"`
-    online_hosts = _parse_nmap_xml [File.read(tmp_file)]
-    offline_addresses = addresses.reject { |a| online_hosts.map(&:remote_address).include?(a) }
-    online_hosts + offline_addresses.map { |a| OpenStruct.new(remote_address: a, host_name: nil, state: 'down') }
-  end
-
-  def self.my_networks
-    my_ip_addresses.map do |a|
-      if a.include?('.')
-        a.split('.')[0..2].join('.') + '.0/24'
-      else
-        raise "No support for IPv6 devices"
-      end
-    end
-  end
-
-  def self.my_ip_addresses
-    Socket.ip_address_list.select { |ai| ai.ipv4? && !ai.ipv4_loopback? }.map(&:ip_address).uniq
-  end
-
-  private
-
-  def self._ensure_nmap_available
-    unless TTY::Which.exist?("nmap")
-      raise "Command 'nmap' not available. Ensure nmap is installed and added to your PATH variable. https://nmap.org'"
-    end
-  end
-
-  def self._parse_nmap_xml(xml_contents)
-    results = {} # use special hash to avoid duplicates easier
-    xml_contents.each do |xml_data|
-      xml_obj = Nokogiri::XML(xml_data)
-      xml_obj.xpath('//nmaprun/host').each do |host|
-        remote_address = host.at('address')['addr']
-        host_name = host.at('hostnames/hostname')&.[]('name')
-        state = host.at('status')&.[]('state')
-        if !results.key?(remote_address) || (results.key?(remote_address) && host_name || state == 'up')
-          old_host_name = results[remote_address]&.host_name
-          results[remote_address] = OpenStruct.new(remote_address: remote_address, host_name: host_name || old_host_name, state: state)
-        end
-      end
-    end
-    puts
-    results.values.select do |r|
-      r.state == 'up' || r.host_name
-    end.map do |r|
-      LanScanner::Device.new host_name: r.host_name, remote_address: r.remote_address, state: r.state
-    end
-  end
+
+require 'socket'
+require 'ostruct'
+require 'tty-which'
+require 'tmpdir'
+require 'nokogiri'
+
+
+require_relative 'lan_scanner/device'
+require_relative 'lan_scanner/version'
+
+module LanScanner
+
+  # @return [Array<LanScanner::Device>] list of devices
+  def self.scan_devices(network: nil)
+    _ensure_nmap_available
+    if network.nil?
+      network = my_networks
+    end
+    network = [network] unless network.is_a? Array
+    sn_xml_results = []
+    tmp_file = "#{Dir.tmpdir}/nmap_scan_#{Random.random_number}.xml"
+    # first we do an -sL scan, which also receives addresses from router/network cache,
+    # that are not found by -sn scan when scanning for the complete network, but are found
+    # with -sn scan, when scanning for this addresses explicitly
+    #
+    # so after this scan we scan for this addresses beneath the networks with -sn
+    sl_xml_results = []
+    network.each do |n|
+      ['-sL'].each do |nmap_type|
+        `nmap #{nmap_type} #{n} -oX "#{tmp_file}"`
+        sl_xml_results.push File.read tmp_file
+        File.delete tmp_file
+      end
+    end
+    # here we scan for the received ip addresses from network cache
+    sl_ips = _parse_nmap_xml sl_xml_results
+    `nmap -sn #{sl_ips.map(&:remote_address).join(' ')} -oX "#{tmp_file}"`
+    sn_xml_results.push File.read tmp_file
+    # here we ping the networks (fast ping which does not detect all)
+    network.each do |n|
+      ['-sn'].each do |nmap_type|
+        `nmap #{nmap_type} #{n} -oX "#{tmp_file}"`
+        sn_xml_results.push File.read tmp_file
+        File.delete tmp_file
+      end
+    end
+    _parse_nmap_xml sn_xml_results
+  end
+
+  # get states of given addresses
+  # @param [Boolean] expensive make expensive check for devices which were not found by fast check already
+  def self.scan_device_states addresses, expensive: false
+    addresses = [addresses] unless addresses.is_a? Array
+    tmp_file = "#{Dir.tmpdir}/nmap_scan_#{Random.random_number}.xml"
+    nmap_scan_option = if expensive
+                   '-Pn'
+                 else
+                   '-sn'
+                 end
+    `nmap -sn #{addresses.join(' ')} -oX "#{tmp_file}"`
+    online_hosts = _parse_nmap_xml [File.read(tmp_file)]
+    offline_addresses = addresses.reject { |a| online_hosts.map(&:remote_address).include?(a) }
+    # check offline addresses again with expensive check
+    if expensive
+      `nmap -Pn #{offline_addresses.join(' ')} -oX "#{tmp_file}"`
+      online_hosts += _parse_nmap_xml [File.read(tmp_file)]
+      offline_addresses = addresses.reject { |a| online_hosts.map(&:remote_address).include?(a) }
+    end
+    online_hosts + offline_addresses.map { |a| OpenStruct.new(remote_address: a, host_name: nil, state: 'down') }
+  end
+
+  def self.my_networks
+    my_ip_addresses.map do |a|
+      if a.include?('.')
+        a.split('.')[0..2].join('.') + '.0/24'
+      else
+        raise "No support for IPv6 devices"
+      end
+    end
+  end
+
+  def self.my_ip_addresses
+    Socket.ip_address_list.select { |ai| ai.ipv4? && !ai.ipv4_loopback? }.map(&:ip_address).uniq
+  end
+
+  private
+
+  def self._ensure_nmap_available
+    unless TTY::Which.exist?("nmap")
+      raise "Command 'nmap' not available. Ensure nmap is installed and added to your PATH variable. https://nmap.org'"
+    end
+  end
+
+  def self._parse_nmap_xml(xml_contents)
+    results = {} # use special hash to avoid duplicates easier
+    xml_contents.each do |xml_data|
+      xml_obj = Nokogiri::XML(xml_data)
+      xml_obj.xpath('//nmaprun/host').each do |host|
+        remote_address = host.at('address')['addr']
+        host_name = host.at('hostnames/hostname')&.[]('name')
+        state = host.at('status')&.[]('state')
+        if !results.key?(remote_address) || (results.key?(remote_address) && host_name || state == 'up')
+          old_host_name = results[remote_address]&.host_name
+          results[remote_address] = OpenStruct.new(remote_address: remote_address, host_name: host_name || old_host_name, state: state)
+        end
+      end
+    end
+    puts
+    results.values.select do |r|
+      r.state == 'up' || r.host_name
+    end.map do |r|
+      LanScanner::Device.new host_name: r.host_name, remote_address: r.remote_address, state: r.state
+    end
+  end
 end
\ No newline at end of file