from netfilterqueue import NetfilterQueue
from scapy.all import *

def print_and_accept(pkt):
print(pkt)
pl = IP(pkt.get_payload())
print(pl.show())
pl[IP].dst = "172.17.0.3"
del pl[IP].len, pl[IP].chksum, pl[TCP].chksum
print(">>>payload: ",str(pl))
pkt.set_payload(str(pl))
hw = pkt.get_hw()
if hw:
print(":".join("{:02x}".format(c) for c in hw[0:6]))
pkt.accept()

nfqueue = NetfilterQueue()
nfqueue.bind(0, print_and_accept)
try:
nfqueue.run()
except KeyboardInterrupt:
print('')

nfqueue.unbind()

following is the output:

###[ IP ]###
version = 4
ihl = 5
tos = 0x0
len = 52
id = 43486
flags = DF
frag = 0
ttl = 127
proto = tcp
chksum = 0x2028
src = /old?u=https%3A%2F%2Fgithub.com%2Fkti%2Fpython-netfilterqueue%2Fissues%2F192.168.197.1%3Cbr&y=1999> dst = 172.17.0.2
\options
###[ TCP ]###
sport = 10732
dport = http
seq = 3132586654
ack = 0
dataofs = 8
reserved = 0
flags = S
window = 64240
chksum = 0xe2cf
urgptr = 0
options = [('MSS', 1460), ('NOP', None), ('WScale', 8), ('NOP', None), ('NOP', None), ('SAckOK', b'')]

None

payload: b'E\x00\x004\xa9\xde@\x00\x7f\x06 (\xc0\xa8\xc5\x01\xac\x11\x00\x03)\xec\x00P\xba\xb7z\x9e\x00\x00\x00\x00\x80\x02\xfa\xf0\xe2\xcf\x00\x00\x02\x04\x05\xb4\x01\x03\x03\x08\x01\x01\x04\x02'
Exception ignored in: 'netfilterqueue.global_callback'
Traceback (most recent call last):
File "nfq3.py", line 10, in print_and_accept
pkt.set_payload(str(pl))
TypeError: Argument 'payload' has incorrect type (expected bytes, got str)