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# -*- coding: binary -*-
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module Rex
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module Proto
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##
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#
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# Quake 3 protocol, taken from ftp://ftp.idsoftware.com/idstuff/quake3/docs/server.txt
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#
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##
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module Quake::Message
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  HEADER = 0xFFFFFFFF
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  def decode_message(message)
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    # minimum size is header (4) + <command> + <stuff>
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    return if message.length < 7
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    header = message.unpack('N')[0]
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    return if header != HEADER
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    message[4, message.length]
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  end
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  def encode_message(payload)
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    [HEADER].pack('N') + payload
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  end
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  def getstatus
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    encode_message('getstatus')
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  end
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  def getinfo
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    encode_message('getinfo')
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  end
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  def decode_infostring(infostring)
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    # decode an "infostring", which is just a (supposedly) quoted string of tokens separated
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    # by backslashes, generally terminated with a newline
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    token_re = /([^\\]+)\\([^\\]+)/
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    return nil unless infostring =~ token_re
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    # remove possibly present leading/trailing double quote
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    infostring.gsub!(/(?:^"|"$)/, '')
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    # remove the trailing \n, if present
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    infostring.gsub!(/\n$/, '')
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    # split on backslashes and group into key value pairs
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    infohash = {}
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    infostring.scan(token_re).each do |kv|
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      infohash[kv.first] = kv.last
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    end
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    infohash
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  end
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  def decode_response(message, type)
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    resp = decode_message(message)
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    if /^print\n(?<error>.*)\n?/m =~ resp
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      # XXX: is there a better exception to throw here?
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      fail ::ArgumentError, "#{type} error: #{error}"
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    # why doesn't this work?
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    # elsif /^#{type}Response\n(?<infostring>.*)/m =~ resp
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    elsif resp =~ /^#{type}Response\n(.*)/m
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      decode_infostring(Regexp.last_match(1))
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    else
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      nil
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    end
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  end
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  def decode_status(message)
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    decode_response(message, 'status')
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  end
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  def decode_info(message)
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    decode_response(message, 'info')
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  end
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end
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end
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end
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