import subprocess import pf """ Doing this the "right" way by using DIOCNATLOOK on the pf device turns out to be a pain. Apple has made a number of modifications to the data structures returned, and compiling userspace tools to test and work with this turns out to be a pain in the ass. Parsing pfctl output is short, simple, and works. Note: Also Tested with FreeBSD 10 pkgng Python 2.7.x. Should work almost exactly as on Mac OS X and except with some changes to the output processing of pfctl (see pf.py). """ class Resolver: STATECMD = ("sudo", "-n", "/sbin/pfctl", "-s", "state") def __init__(self): pass def original_addr(self, csock): peer = csock.getpeername() try: stxt = subprocess.check_output(self.STATECMD, stderr=subprocess.STDOUT) except subprocess.CalledProcessError: return None return pf.lookup(peer[0], peer[1], stxt)