1#!/usr/local/bin/python2.7 2 3print "non-overlapping ping fragments" 4 5# |--------| 6# |----| 7 8import os 9from addr import * 10from scapy.all import * 11 12pid=os.getpid() 13eid=pid & 0xffff 14payload="ABCDEFGHIJKLMNOP" 15packet=IP(src=LOCAL_ADDR, dst=REMOTE_ADDR)/ \ 16 ICMP(type='echo-request', id=eid)/payload 17frag=[] 18fid=pid & 0xffff 19frag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid, 20 flags='MF')/str(packet)[20:36]) 21frag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid, 22 frag=2)/str(packet)[36:44]) 23eth=[] 24for f in frag: 25 eth.append(Ether(src=LOCAL_MAC, dst=REMOTE_MAC)/f) 26 27if os.fork() == 0: 28 time.sleep(1) 29 sendp(eth, iface=LOCAL_IF) 30 os._exit(0) 31 32ans=sniff(iface=LOCAL_IF, timeout=3, filter= 33 "ip and src "+REMOTE_ADDR+" and dst "+LOCAL_ADDR+" and icmp") 34for a in ans: 35 if a and a.type == ETH_P_IP and \ 36 a.payload.proto == 1 and \ 37 a.payload.frag == 0 and a.payload.flags == 0 and \ 38 icmptypes[a.payload.payload.type] == 'echo-reply': 39 id=a.payload.payload.id 40 print "id=%#x" % (id) 41 if id != eid: 42 print "WRONG ECHO REPLY ID" 43 exit(2) 44 data=a.payload.payload.payload.load 45 print "payload=%s" % (data) 46 if data == payload: 47 exit(0) 48 print "PAYLOAD!=%s" % (payload) 49 exit(1) 50print "NO ECHO REPLY" 51exit(2) 52