Class: HiddenHippo::Scanner

Inherits:
Object
  • Object
show all
Defined in:
lib/hidden_hippo/scanner.rb

Instance Method Summary collapse

Constructor Details

#initialize(file, packet_class, *extractors) ⇒ Scanner

Returns a new instance of Scanner.



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# File 'lib/hidden_hippo/scanner.rb', line 5

def initialize(file, packet_class, *extractors)
  @file = file
  @extractors = extractors
  @packet_class = packet_class
end

Instance Method Details

#call ⇒ Object 



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# File 'lib/hidden_hippo/scanner.rb', line 11

def call
  # call Tshark
  tshark_fields = @packet_class.tshark_fields

  args = [
      '-2', '-Tfields', '-q',
      '-r', @file,
      '-R', @packet_class.filter,
      *tshark_fields.map {|f| ['-e', f]}.flatten
  ]

  Open3.popen3(%w(tshark tshark), *args) do |stdin, stdout, stderr, waiter|
    # we don't need those
    stdin.close

    stdout.each do |line|
      if line.count("\t") != tshark_fields.size - 1
        puts 'Warinig: tshark returned a line of the wrong size. Ignoring it.'
        puts "Offending line: #{line}"
        next
      end

      split_line = line.chomp.split("\t")
                   .map(&:rstrip).map(&:lstrip)
                   .map {|f| f.empty? ? nil : f}

      assoc = tshark_fields.zip split_line
      packet = @packet_class.parse Hash[*assoc.flatten]

      @extractors.each do |extractor|
        extractor.call(packet)
      end
    end

    if waiter.value != 0
      puts "Warning: tshark exited with status code #{waiter.value}."
      puts "tshark #{args.join(' ')}"
      puts stderr.read
    end
  end
end