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')
        result = connSkt.recv(100)
        screenLock.acquire()
        print '[+]%d/tcp open'% tgtPort
        print '[+] ' + str(results)
    except:
        screenLock.acquire()
        print '[-]%d/tcp closed'% tgtPort
    finally:
        screenLock.release()
        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='string', \
                  help='specify target port[s] separated by commas')
    (options, args) = parser.parse_args()
    tgtHost = options.tgtHost
    tgtPorts = str(options.tgtPort).replace(' ', '')
    tgtPorts = tgtPorts.split(',')
    
    if (tgtHost == None) | (tgtPorts[0] == None):
        print parser.usage
        exit(0)
    portScan(tgtHost, tgtPorts)

if __name__ == '__main__':
    main()
