1*647ac401Sbluhm#!/usr/local/bin/python3 23fe81ad4Sbluhm 3*647ac401Sbluhmprint("ping fragment that overlaps the second fragment with its head") 43fe81ad4Sbluhm 53fe81ad4Sbluhm# |----| 63fe81ad4Sbluhm# |----| 73fe81ad4Sbluhm# |XXXX-----| 83fe81ad4Sbluhm 93fe81ad4Sbluhmimport os 103fe81ad4Sbluhmfrom addr import * 113fe81ad4Sbluhmfrom scapy.all import * 123fe81ad4Sbluhm 133fe81ad4Sbluhmpid=os.getpid() 143fe81ad4Sbluhmeid=pid & 0xffff 15*647ac401Sbluhmpayload=b"ABCDEFGHIJKLMNOP" 16*647ac401Sbluhmdummy=b"01234567" 173fe81ad4Sbluhmpacket=IP(src=LOCAL_ADDR, dst=REMOTE_ADDR)/ \ 183fe81ad4Sbluhm ICMP(type='echo-request', id=eid)/payload 193fe81ad4Sbluhmfrag=[] 203fe81ad4Sbluhmfid=pid & 0xffff 213fe81ad4Sbluhmfrag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid, 22*647ac401Sbluhm flags='MF')/bytes(packet)[20:28]) 233fe81ad4Sbluhmfrag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid, 24*647ac401Sbluhm frag=1, flags='MF')/bytes(packet)[28:36]) 253fe81ad4Sbluhmfrag.append(IP(src=LOCAL_ADDR, dst=REMOTE_ADDR, proto=1, id=fid, 26*647ac401Sbluhm frag=1)/(dummy+bytes(packet)[36:44])) 273fe81ad4Sbluhmeth=[] 283fe81ad4Sbluhmfor f in frag: 293fe81ad4Sbluhm eth.append(Ether(src=LOCAL_MAC, dst=REMOTE_MAC)/f) 303fe81ad4Sbluhm 313fe81ad4Sbluhmif os.fork() == 0: 323fe81ad4Sbluhm time.sleep(1) 333fe81ad4Sbluhm sendp(eth, iface=LOCAL_IF) 343fe81ad4Sbluhm os._exit(0) 353fe81ad4Sbluhm 363fe81ad4Sbluhmans=sniff(iface=LOCAL_IF, timeout=3, filter= 373fe81ad4Sbluhm "ip and src "+REMOTE_ADDR+" and dst "+LOCAL_ADDR+" and icmp") 383fe81ad4Sbluhmfor a in ans: 393fe81ad4Sbluhm if a and a.type == ETH_P_IP and \ 403fe81ad4Sbluhm a.payload.proto == 1 and \ 413fe81ad4Sbluhm a.payload.frag == 0 and a.payload.flags == 0 and \ 423fe81ad4Sbluhm icmptypes[a.payload.payload.type] == 'echo-reply': 433fe81ad4Sbluhm id=a.payload.payload.id 44*647ac401Sbluhm print("id=%#x" % (id)) 453fe81ad4Sbluhm if id != eid: 46*647ac401Sbluhm print("WRONG ECHO REPLY ID") 473fe81ad4Sbluhm exit(2) 483fe81ad4Sbluhm data=a.payload.payload.payload.load 49*647ac401Sbluhm print("payload=%s" % (data)) 503fe81ad4Sbluhm if data == payload: 513fe81ad4Sbluhm exit(0) 52*647ac401Sbluhm print("PAYLOAD!=%s" % (payload)) 533fe81ad4Sbluhm exit(1) 54*647ac401Sbluhmprint("NO ECHO REPLY") 553fe81ad4Sbluhmexit(2) 56