# Copyright (C) 1998-2018 by the Free Software Foundation, Inc.
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
"""Netscape Messaging Server bounce formats.
I've seen at least one NMS server version 3.6 (envy.gmp.usyd.edu.au) bounce
messages of this format. Bounces come in DSN MIME format, but don't include
any -Recipient: headers. Gotta just parse the text :(
NMS 4.1 (dfw-smtpin1.email.verio.net) seems even worse, but we'll try to
decipher the format here too.
"""
import re
from cStringIO import StringIO
pcre = re.compile(
r'This Message was undeliverable due to the following reason:',
re.IGNORECASE)
acre = re.compile(
r'(?P<reply>please reply to)?.*<(?P<addr>[^>]*)>',
re.IGNORECASE)
def flatten(msg, leaves):
# give us all the leaf (non-multipart) subparts
if msg.is_multipart():
for part in msg.get_payload():
flatten(part, leaves)
else:
leaves.append(msg)
def process(msg):
# Sigh. Some show NMS 3.6's show
# multipart/report; report-type=delivery-status
# and some show
# multipart/mixed;
if not msg.is_multipart():
return None
# We're looking for a text/plain subpart occuring before a
# message/delivery-status subpart.
plainmsg = None
leaves = []
flatten(msg, leaves)
for i, subpart in zip(range(len(leaves)-1), leaves):
if subpart.get_content_type() == 'text/plain':
plainmsg = subpart
break
if not plainmsg:
return None
# Total guesswork, based on captured examples...
body = StringIO(plainmsg.get_payload())
addrs = []
while 1:
line = body.readline()
if not line:
break
mo = pcre.search(line)
if mo:
# We found a bounce section, but I have no idea what the official
# format inside here is. :( We'll just search for <addr>
# strings.
while 1:
line = body.readline()
if not line:
break
mo = acre.search(line)
if mo and not mo.group('reply'):
addrs.append(mo.group('addr'))
return addrs
