[Python] Port Scanner

# -*- coding: cp949 -*-
import optparse
from socket import *
from threading import *
 
screenLock = Semaphore(value=1)
 
def connScan(tgtHost, tgtPort):
    try:
        connSkt = socket(AF_INET, SOCK_STREAM)
        connSkt.connect(tgtHost, tgtPort)
        connSkt.send('ViolentPython\r\n')
        results = connSkt.recv(100)
        screenLock.acquire()        # 출력하기 전에 세마포어 습득
        print '[+]%d/tcp open'% tgtPort
        print '[+] ' +str(results)
    except:
        screenLock.acquire()        # 출력하기 전에 세마포어 습득
        print '[-]%d/tcp closed'% tgtPort
    finally:
        screenLock.release()        # 쓰레드가 끝날 때 놓아줌
        connSkt.close()
        
def portScan(tgtHost, tgtPorts):
    try:
        tgtIP = gethostbyname(tgtHost)
    except:
        print "[-] Cannot resolve '%s': Unknown host" %tgtHost
        return
    try:
        tgtName = gethostbyaddr(tgtIP)
        print '\n[+] Scan Results for: ' + tgtName[0]
    except:
        print '\n[+] Scan Results for: ' + tgtIP
    setdefaulttimeout(1)
    for tgtPort in tgtPorts:
        t = Thread(target=connScan, args=(tgtHost, int(tgtPort)))
        t.start()
        
def main():
    parser = optparse.OptionParser('usage %prog -H <target host> -p <target port>')
    parser.add_option('-H', dest='tgtHost', type='string', help='specify target host')
    parser.add_option('-p', dest='tgtPort', type='int', help='specify target port[s] separated by comma')
    (options, args) = parser.parse_args()
    tgtHost = options.tgtHost
    tgtPort = str(options.tgtPort).split(', ')
    if (tgtHost == None) | (tgtPort == None):
        print '[-] You must specify a target host and port[s].'
        exit(0)
    portScan(tgtHost, tgtPorts)
 
if __name__ == '__main__':
    main()
 

출처 : Violent Python ( 해커의 언어, 치명적 파이썬)