import socket
import threading
import time
import struct
import Queue
queue = Queue.Queue()
def udp_sender(ip,port):
try:
ADDR = (ip,port)
sock_udp = socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
sock_udp.sendto("abcd...",ADDR)
sock_udp.close()
except:
pass
def icmp_receiver(ip,port):
icmp = socket.getprotobyname("icmp")
try:
sock_icmp = socket.socket(socket.AF_INET, socket.SOCK_RAW, icmp)
except socket.error, (errno, msg):
if errno == 1:
# Operation not permitted
msg = msg + (
" - Note that ICMP messages can only be sent from processes"
" running as root."
)
raise socket.error(msg)
raise # raise the original error
sock_icmp.settimeout(3)
try:
recPacket,addr = sock_icmp.recvfrom(64)
except:
queue.put(True)
return
icmpHeader = recPacket[20:28]
icmpPort = int(recPacket.encode('hex')[100:104],16)
head_type, code, checksum, packetID, sequence = struct.unpack(
"bbHHh", icmpHeader
)
sock_icmp.close()
if code == 3 and icmpPort == port and addr[0] == ip:
queue.put(False)
return
def checker_udp(ip,port):
thread_udp = threading.Thread(target=udp_sender,args=(ip,port))
thread_icmp = threading.Thread(target=icmp_receiver,args=(ip,port))
thread_udp.daemon= True
thread_icmp.daemon = True
thread_icmp.start()
time.sleep(0.1)
thread_udp.start()
thread_icmp.join()
thread_udp.join()
return queue.get(False)
if __name__ == '__main__':
import sys
print checker_udp(sys.argv[1],int(sys.argv[2]))
