frag6_udpatomic.py revision 1.8
1#!/usr/local/bin/python2.7 2 3print "atomic udp fragment" 4 5# |-------------| 6 7import os 8from addr import * 9from scapy.all import * 10 11pid=os.getpid() 12uport=pid & 0xffff 13# inetd ignores UDP packets from privileged port or nfs 14if uport < 1024 or uport == 2049: 15 uport+=1024 16payload="ABCDEFGHIJKLMNOP" 17packet=IPv6(src=LOCAL_ADDR6, dst=REMOTE_ADDR6)/ \ 18 UDP(sport=uport, dport=7)/payload 19frag=[] 20fid=pid & 0xffffffff 21frag.append(IPv6ExtHdrFragment(nh=17, id=fid)/str(packet)[40:64]) 22eth=[] 23for f in frag: 24 pkt=IPv6(src=LOCAL_ADDR6, dst=REMOTE_ADDR6)/f 25 eth.append(Ether(src=LOCAL_MAC, dst=REMOTE_MAC)/pkt) 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 "ip6 and src "+REMOTE_ADDR6+" and dst "+LOCAL_ADDR6+" and udp") 34for a in ans: 35 if a and a.type == ETH_P_IPV6 and \ 36 ipv6nh[a.payload.nh] == 'UDP' and \ 37 a.payload.payload.sport == 7: 38 port=a.payload.payload.dport 39 print "port=%d" % (port) 40 if port != uport: 41 print "WRONG UDP ECHO REPLY PORT" 42 exit(2) 43 data=a.payload.payload.load 44 print "payload=%s" % (data) 45 if data == payload: 46 exit(0) 47 print "PAYLOAD!=%s" % (payload) 48 exit(1) 49print "NO UDP ECHO REPLY" 50exit(2) 51