xref: /aosp_15_r20/external/scapy/test/sendsniff.uts (revision 7dc08ffc4802948ccbc861daaf1e81c405c2c4bd)

% send, sniff, sr* tests for Scapy

~ netaccess

############
############
+ Test bridge_and_sniff() using tap sockets

~ tap linux

= Create two tap interfaces

import subprocess
from threading import Thread

tap0, tap1 = [TunTapInterface("tap%d" % i) for i in range(2)]

if LINUX:
    for i in range(2):
        assert subprocess.check_call(["ip", "link", "set", "tap%d" % i, "up"]) == 0
else:
    for i in range(2):
        assert subprocess.check_call(["ifconfig", "tap%d" % i, "up"]) == 0

= Run a sniff thread on the tap1 **interface**
* It will terminate when 5 IP packets from 1.2.3.4 have been sniffed
t_sniff = Thread(
    target=sniff,
    kwargs={"iface": "tap1", "count": 5, "prn": Packet.summary,
            "lfilter": lambda p: IP in p and p[IP].src == "1.2.3.4"}
)
t_sniff.start()

= Run a bridge_and_sniff thread between the taps **sockets**
* It will terminate when 5 IP packets from 1.2.3.4 have been forwarded
t_bridge = Thread(target=bridge_and_sniff, args=(tap0, tap1),
                  kwargs={"store": False, "count": 5, 'prn': Packet.summary,
                          "lfilter": lambda p: IP in p and p[IP].src == "1.2.3.4"})
t_bridge.start()

= Send five IP packets from 1.2.3.4 to the tap0 **interface**
time.sleep(1)
sendp([Ether(dst=ETHER_BROADCAST) / IP(src="1.2.3.4") / ICMP()], iface="tap0",
      count=5)

= Wait for the threads
t_bridge.join()
t_sniff.join()

= Run a sniff thread on the tap1 **interface**
* It will terminate when 5 IP packets from 2.3.4.5 have been sniffed
t_sniff = Thread(
    target=sniff,
    kwargs={"iface": "tap1", "count": 5, "prn": Packet.summary,
            "lfilter": lambda p: IP in p and p[IP].src == "2.3.4.5"}
)
t_sniff.start()

= Run a bridge_and_sniff thread between the taps **sockets**
* It will "NAT" packets from 1.2.3.4 to 2.3.4.5 and will terminate when 5 IP packets have been forwarded
def nat_1_2(pkt):
    if IP in pkt and pkt[IP].src == "1.2.3.4":
        pkt[IP].src = "2.3.4.5"
        del pkt[IP].chksum
        return pkt
    return False

t_bridge = Thread(target=bridge_and_sniff, args=(tap0, tap1),
                  kwargs={"store": False, "count": 5, 'prn': Packet.summary,
                          "xfrm12": nat_1_2,
                          "lfilter": lambda p: IP in p and p[IP].src == "1.2.3.4"})
t_bridge.start()

= Send five IP packets from 1.2.3.4 to the tap0 **interface**
time.sleep(1)
sendp([Ether(dst=ETHER_BROADCAST) / IP(src="1.2.3.4") / ICMP()], iface="tap0",
      count=5)

= Wait for the threads
t_bridge.join()
t_sniff.join()

= Delete the tap interfaces
del tap0, tap1


############
############
+ Test bridge_and_sniff() using tun sockets

~ tun linux not_pcapdnet

= Create two tun interfaces

import subprocess
from threading import Thread

tun0, tun1 = [TunTapInterface("tun%d" % i) for i in range(2)]

if LINUX:
    for i in range(2):
        assert subprocess.check_call(["ip", "link", "set", "tun%d" % i, "up"]) == 0
else:
    for i in range(2):
        assert subprocess.check_call(["ifconfig", "tun%d" % i, "up"]) == 0

= Run a sniff thread on the tun1 **interface**
* It will terminate when 5 IP packets from 1.2.3.4 have been sniffed
t_sniff = Thread(
    target=sniff,
    kwargs={"iface": "tun1", "count": 5, "prn": Packet.summary,
            "lfilter": lambda p: IP in p and p[IP].src == "1.2.3.4"}
)
t_sniff.start()

= Run a bridge_and_sniff thread between the tuns **sockets**
* It will terminate when 5 IP packets from 1.2.3.4 have been forwarded.
t_bridge = Thread(target=bridge_and_sniff, args=(tun0, tun1),
                  kwargs={"store": False, "count": 5, 'prn': Packet.summary,
                          "xfrm12": lambda pkt: pkt,
                          "lfilter": lambda p: IP in p and p[IP].src == "1.2.3.4"})
t_bridge.start()

= Send five IP packets from 1.2.3.4 to the tun0 **interface**
time.sleep(1)
conf.route.add(net="1.2.3.4/32", dev="tun0")
send(IP(src="1.2.3.4", dst="1.2.3.4") / ICMP(), count=5)
conf.route.delt(net="1.2.3.4/32", dev="tun0")

= Wait for the threads
t_bridge.join()
t_sniff.join()

= Run a sniff thread on the tun1 **interface**
* It will terminate when 5 IP packets from 2.3.4.5 have been sniffed
t_sniff = Thread(
    target=sniff,
    kwargs={"iface": "tun1", "count": 5, "prn": Packet.summary,
            "lfilter": lambda p: IP in p and p[IP].src == "2.3.4.5"}
)
t_sniff.start()

= Run a bridge_and_sniff thread between the tuns **sockets**
* It will "NAT" packets from 1.2.3.4 to 2.3.4.5 and will terminate when 5 IP packets have been forwarded
def nat_1_2(pkt):
    if IP in pkt and pkt[IP].src == "1.2.3.4":
        pkt[IP].src = "2.3.4.5"
        del pkt[IP].chksum
        return pkt
    return False

t_bridge = Thread(target=bridge_and_sniff, args=(tun0, tun1),
                  kwargs={"store": False, "count": 5, 'prn': Packet.summary,
                          "xfrm12": nat_1_2,
                          "lfilter": lambda p: IP in p and p[IP].src == "1.2.3.4"})
t_bridge.start()

= Send five IP packets from 1.2.3.4 to the tun0 **interface**
time.sleep(1)
conf.route.add(net="1.2.3.4/32", dev="tun0")
send(IP(src="1.2.3.4", dst="1.2.3.4") / ICMP(), count=5)
conf.route.delt(net="1.2.3.4/32", dev="tun0")

= Wait for the threads
t_bridge.join()
t_sniff.join()

= Delete the tun interfaces
del tun0, tun1