Python 포트 스캔(socket, threading, Queue, gc, optparse)

import os
import gc
import errno
import socket
import optparse
from threading import Thread
from Queue import Queue
 
socket_timeout = 0.1
thread_size = 100
default_max_port = 65535
gc_cycle = 1000
max_retries = 0
 
in_queue = Queue()
out_queue = Queue()
 
def test_conn(host, port):
    try:
        for _ in range(max_retries+1):
            try:
                sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                sock.settimeout(socket_timeout)
                sock.connect((host, port))
                if sock:
                    sock.close()
                    return True
            except socket.timeout:
                pass
    except socket.error as e:
        if e.errno != errno.ECONNREFUSED:
            raise e
    return False
 
def set_scan_ports(ports):
    for port in ports:
        if port:
            in_queue.put(port)
    for i in range(thread_size):
        in_queue.put(None)
 
def thread_scan_port(host):
    count = 0
    while True:
        port = in_queue.get()
        if port is None:
            in_queue.task_done()
            break
 
        out = test_conn(host, port)
        data = {
            'port': port,
            'return': out
        }
        out_queue.put(data)
        in_queue.task_done()
 
        count += 1
        if count == gc_cycle:
            gc.collect()
            count = 0
 
def scan_port(host, ports=None, thread=True):
    #socket.setdefaulttimeout(socket_timeout)
    if not ports:
        ports = range(1, default_max_port+1)
    set_scan_ports(ports)
    opened_ports = []
    if thread:
        ts = []
        for i in range(thread_size):
            t = Thread(target=thread_scan_port, args=(host,))
            t.start()
            ts.append(t)
 
        for t in ts:
            t.join()
 
        while not out_queue.empty():
            out = out_queue.get()
            if out['return']:
                opened_ports.append(out['port'])
    else:
        for port in ports:
            if test_conn(host, port):
                opened_ports.append(port)
    return opened_ports
 
# Main Function Area
def main():
    parser = optparse.OptionParser(usage='Usage %Prog -H <Target Host> -p <Target Port>')
    parser.add_option('-H', dest = 'host', type ='string', help = 'Specify Target IP')
    parser.add_option('-p', dest = 'ports', type ='string', help = 'Specify Target Port')
    (options, args) = parser.parse_args()
 
    host = options.host
    ports = options.ports
    if ports:
        ports = str(ports).split(',')
        _ports = []
        for port in ports:
            if port.count("-"):
                start, end = port.split("-", 1)
                _ports += range(int(start), int(end)+1)
            else:
                _ports.append(int(port))
        ports = _ports
 
    if host == None:
        print parser.usage
        os._exit(1)
    print scan_port(host, ports)
 
if __name__ == '__main__':
    main()