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#!/usr/local/bin/python3
print("drop too long fragment queue, reassemble less fragments")
# |----|
# |----|
# |----|
# ... ...
# |----|
import os
from addr import *
from scapy.all import *
pid=os.getpid()
eid=pid & 0xffff
payload=b"ABCDEFGHIJKLMNOP" * 70
frag=[]
fid=pid & 0xffffffff
# send packets with 65 and 64 fragments
for max in (64, 63):
eid = ~eid & 0xffff
packet=IPv6(src=LOCAL_ADDR6, dst=REMOTE_ADDR6)/ \
ICMPv6EchoRequest(id=eid, data=payload)
fid = ~fid & 0xffffffff
for i in range(max):
frag.append(IPv6ExtHdrFragment(nh=58, id=fid, m=1,
offset=i)/bytes(packet)[40+i*8:40+(i+1)*8])
frag.append(IPv6ExtHdrFragment(nh=58, id=fid,
offset=max)/bytes(packet)[40+max*8:])
eth=[]
for f in frag:
pkt=IPv6(src=LOCAL_ADDR6, dst=REMOTE_ADDR6)/f
eth.append(Ether(src=LOCAL_MAC, dst=REMOTE_MAC)/pkt)
child = os.fork()
if child == 0:
time.sleep(1)
for e in eth:
sendp(e, iface=LOCAL_IF)
time.sleep(0.001)
os._exit(0)
ans=sniff(iface=LOCAL_IF, timeout=6, filter=
"ip6 and src "+REMOTE_ADDR6+" and dst "+LOCAL_ADDR6+" and icmp6")
os.kill(child, 15)
os.wait()
reply=False
for a in ans:
if a and a.type == ETH_P_IPV6 and \
ipv6nh[a.payload.nh] == 'ICMPv6' and \
icmp6types[a.payload.payload.type] == 'Echo Reply':
id=a.payload.payload.id
print("id=%#x" % (id))
if id == ~eid & 0xffff:
print("ECHO REPLY FROM 65 FRAGMENTS")
exit(1)
if id != eid:
print("WRONG ECHO REPLY ID")
exit(2)
data=a.payload.payload.data
print("payload=%s" % (data))
if data != payload:
print("PAYLOAD!=%s" % (payload))
exit(2)
reply=True
if not reply:
print("NO ECHO REPLY FROM 64 FRAGMENTS")
exit(1)
exit(0)
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