From: David Tillman <dtillman@...>
Date: 2001-09-22T04:57:39+09:00
Subject: [ruby-talk:21499] Speed




  Hello all,

    I would like to speed up the following bit of code if possible.
    This is sort of a toy proxy server.

    I initially knocked it together earlier this week when the latest
    MS IIS exploit was announced.  One thing the offending virus does
    is attach a javascript command to fetch a "readme.eml" from the
    infected server.

    We use squid as a caching proxy server.  This bit of code goes
    between the client and the proxy server and rewrites pages on the
    fly.

    One could have great fun with an unsuspecting victim as you
    insert their name in place of George Bush, whatever.  My actual
    intentions were to replace "readme.eml" with something benign.
    It also works quite well as a banner-ad killer.

    With a little effort it could also be made to cache pages and
    retrieve pages directly.  As I already have squid for that I
    didn't want to reinvent the wheel.
    
    As it stands now the speed is acceptable, but a bit on the slow
    side.  Is there anything I can do to optimize? (besides turning
    off the debug info)

    -Dave



#!/usr/local/bin/ruby


require 'tempfile'
require 'socket'


Rproxy_port = 3031
Squid_port = 3128
Host = '172.16.16.13'


server = TCPServer.new(Host, Rproxy_port)


while TRUE
  
  Thread.new(session = server.accept) { |my_session|
    puts "***Thread count: #{Thread.list.length}"
    puts "***#{Thread.current}: Accepted connection from client."    
    
    squid = TCPSocket.new(Host, Squid_port)
    puts "***#{Thread.current}: Opened socket to squid."
    
    request = my_session.recvfrom(2048)
    print "***#{Thread.current}: Request: #{request[0]}\n"
    
    squid.print(request[0])
    puts "***#{Thread.current}: Gave request to squid."
    
    
    tf = Tempfile.new("rproxy")
    
    answer = squid.recvfrom(1024)
    while (answer[0].length > 0)
      tf.print(answer[0])
      answer = squid.recvfrom(1024)
    end
    
    squid.close
    puts "***#{Thread.current}: Closed socket to squid."
    
    tf.pos = 0
    
    headers = {}
    line = tf.gets("\r\n")
    while (line != "\r\n")
      line.chomp!("\r\n")
      title, data = line.split(/: /)
      headers[title] = data
      line = tf.gets
    end
    
    tf.pos = 0
    
    
    if (headers["Content-Type"] == "text/html")
      while (answer = tf.gets("\r\n"))
	answer.gsub!(/readme\.eml/, "foo.html")
	my_session.print answer
      end
    else
      answer = tf.read(1024)
      while (answer)
	my_session.print answer
	answer = tf.read(1024)
      end
      
    end    
    
    my_session.close
    puts "***#{Thread.current}: Closed socket to client."
    
    
    tf.close
    
    puts "***#{Thread.current}: Content-Type = #{headers['Content-Type']}"
  }
  
  
end