# == Synopsis
# semtex00.rb -- solution in ruby to level 00 of the Semtex Wargame
#                located at http://www.pulltheplug.org
#                
# Connect to port 24000 and receive data until the port is closed.
# Every second byte you receive is trash, ignore it.
# The other bytes are an elf executable that shows you the password.
#
# Then login to semtex1@semtex.labs.pulltheplug.org
#
# == Usage
# ruby semtex00.rb [ -h | --help ] [ -v | --version ]
# 
# == Author
# Beau Grantham
# beau@thedarkmere.net
# 
# == Version
# 0x2 2006/05/03

require 'socket'
require 'rdoc/usage'
require 'optparse'

# RDoc
opts = OptionParser.new
opts.on("-h", "--help") { RDoc::usage }
opts.on("-v", "--version") { RDoc::usage('version') }
opts.parse(ARGV) rescue RDoc::usage('usage')

server  = "69.55.233.83"
port    = "24000"
outFile = "semtex00"
i       = 0

# Open file
writeTo = File.open(outFile, "w")

# Connect socket
print "Connecting to #{server}:#{port}... "
sock = TCPSocket.new(server, port)
puts  "Success!"

# Read and write every other byte
print "Reading data... "
while (byte = sock.read(1))
  writeTo.print byte if ((i += 1)%2 != 0)
end

# Close file
writeTo.close

puts (i).to_s + " bytes read."
puts "Write to file successful."
puts "Run 'chmod +x #{outFile} && ./#{outFile}'"