python - Python DNS ファインダー

Question

こんにちは、github で Gist のこのコードを取得し、独自の小さな調整を追加しましたが、かなり遅いです。速度を上げる方法はありますか? スレッドを試してみましたが、ファイルへの書き込みに問題が発生するだけなので、どうすれば高速化できますか?

# dnsfind.py <startip> <endip>

import sys
import socket
import struct
import threading
import os
import time

# basic DNS header for 1 query
def buildDNSQuery(host):
    packet=struct.pack("!HHHHHH", 0x0001, 0x0100, 1, 0, 0, 0)

    for name in host:
         query=struct.pack("!b"+str(len(name))+"s", len(name), name)
         packet=packet+query

    packet=packet+struct.pack("!bHH",0,1,1)

    return packet

    # just ask for www.google.com
    TEST_QUERY=buildDNSQuery(["www","google","com"])
    DNS_PORT=53
    TIMEOUT=2
  # scan a server for DNS
    def ScanDNS(addr, timeout):
          s=socket.socket(socket.AF_INET, socket.SOCK_DGRAM, 0)
          s.settimeout(TIMEOUT)

  # send DNS question to server
          sendcount=s.sendto(TEST_QUERY, 0, (addr,DNS_PORT))
          if sendcount <= 0:
               return False

    # wait for response
         try:
             recvdata=s.recvfrom(1024)
         except socket.error, e:
               return False

        return True

   # extract an ip address into a tuple of integers
  def ExtractIP(ip):
        partip=ip.split(".")
        if len(partip) != 4:
            print "Invalid ip address: "+ip
        try:
             iptuple=(int(partip[0]),int(partip[1]),int(partip[2]),int(partip[3]))
        except ValueError:
             print "Invalid ip address: "+ip

        return iptuple

if len(sys.argv) < 2:
       print "Not enough parameters supplied!"

# convert ip address to integer tuple
STARTs_IP=ExtractIP(sys.argv[1])
ENDs_IP=ExtractIP(sys.argv[2])
File = open("file.txt","wb")
def main(START_IP,END_IP):
    # store found DNS servers
    foundDNS=[]

    # scan all the ip addresses in the range
    for i0 in range(START_IP[0], END_IP[0]+1):
        for i1 in range(START_IP[1], END_IP[1]+1):
            for i2 in range(START_IP[2], END_IP[2]+1):
                for i3 in range(START_IP[3], END_IP[3]+1):
                   # build ip addres
                   ipaddr=str(i0)+"."+str(i1)+"."+str(i2)+"."+str(i3)

                   print "Scanning "+ipaddr+"...",
                   # scan address
                   ret=ScanDNS(ipaddr, 10)

                   if ret==True:
                       foundDNS.append(ipaddr)
                       print "Found!"
                       File.write(ipaddr)
                       File.write("\n")
                   else:
                        print 

                   # print out all found servers

 if __name__ == "__main__":
     main(STARTs_IP,ENDs_IP)