milter-nomix.py
from __future__ import print_function
import Milter
import time
import sys
from Milter.utils import parse_addr
internal_tlds = ["corp", "personal"]
def is_internal(hostname):
components = hostname.split(".")
return components.pop() in internal_tlds
# Determine if internal and external hosts are mixed based on a list
# of hostnames
def are_mixed(hostnames):
hostnames_mapped = map(is_internal, hostnames)
# Num internals
num_internal_hosts = hostnames_mapped.count(True)
# Num externals
num_external_hosts = hostnames_mapped.count(False)
return num_external_hosts >= 1 and num_internal_hosts >= 1
class NoMixMilter(Milter.Base):
def __init__(self): # A new instance with each new connection.
self.id = Milter.uniqueID() # Integer incremented with each call.
@Milter.noreply
def envfrom(self, mailfrom, *str):
self.mailfrom = mailfrom
self.domains = []
t = parse_addr(mailfrom)
if len(t) > 1:
self.domains.append(t[1])
else:
self.domains.append('local')
self.internal = False
return Milter.CONTINUE
def envrcpt(self, to, *str):
self.R.append(to)
t = parse_addr(to)
if len(t) > 1:
self.domains.append(t[1])
else:
self.domains.append('local')
if are_mixed(self.domains):
# FIXME: log recipients collected in self.mailfrom and self.R
self.setreply('550','5.7.1','Mixing internal and external TLDs')
return Milter.REJECT
return Milter.CONTINUE
def main():
socketname = "/var/run/nomixsock"
timeout = 600
# Register to have the Milter factory create instances of your class:
Milter.factory = NoMixMilter
print("%s milter startup" % time.strftime('%Y%b%d %H:%M:%S'))
sys.stdout.flush()
Milter.runmilter("nomixfilter",socketname,timeout)
logq.put(None)
bt.join()
print("%s nomix milter shutdown" % time.strftime('%Y%b%d %H:%M:%S'))
if __name__ == "__main__":
main()
Milter.uniqueID
def uniqueID()
Definition: __init__.py:29
Milter.runmilter
def runmilter(name, socketname, timeout=0, rmsock=True)
Run the milter.
Definition: __init__.py:757
Milter.Base
A do "nothing" Milter base class representing an SMTP connection.
Definition: __init__.py:238
Milter.utils
Definition: utils.py:1