Files
infix/test/infamy/sniffer.py
T
2023-12-14 16:40:41 +01:00

41 lines
1.1 KiB
Python

"""Sniff for network packets using tcpdump/tshark"""
import os
import signal
import subprocess
import tempfile
import time
class Sniffer:
"""Helper class for tcpdump"""
def __init__(self, netns, expr):
self.pcap = tempfile.NamedTemporaryFile(suffix=".pcap", delete=False)
self.expr = expr
self.netns = netns
self.proc = None
def __del__(self):
self.pcap.close()
os.unlink(self.pcap.name)
def __enter__(self):
cmd = f"tshark -lni iface -w {self.pcap.name} {self.expr}"
arg = cmd.split(" ")
self.proc = self.netns.popen(arg, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
def __exit__(self, _, __, ___):
if not self.proc:
return False
self.proc.send_signal(signal.SIGINT)
time.sleep(1)
if not self.proc.poll():
try:
self.proc.kill()
except OSError:
pass
self.proc.wait()
def output(self):
"""Return PCAP output"""
return self.netns.runsh(f"tshark -n -r {self.pcap.name}")