# 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.
"""Parse bounce messages generated by qmail.
Qmail actually has a standard, called QSBMF (qmail-send bounce message
format), as described in
http://cr.yp.to/proto/qsbmf.txt
This module should be conformant.
"""
import re
import email.Iterators
# Other (non-standard?) intros have been observed in the wild.
introtags = [
'Hi. This is the',
'Hi. The MTA program at',
"We're sorry. There's a problem",
'Check your send e-mail address.',
'This is the mail delivery agent at',
'Unfortunately, your mail was not delivered',
'Your mail message to the following',
]
acre = re.compile(r'<(?P<addr>[^>]*)>:')
def process(msg):
addrs = []
# simple state machine
# 0 = nothing seen yet
# 1 = intro paragraph seen
# 2 = recip paragraphs seen
state = 0
for line in email.Iterators.body_line_iterator(msg):
line = line.strip()
if state == 0:
for introtag in introtags:
if line.startswith(introtag):
state = 1
break
elif state == 1 and not line:
# Looking for the end of the intro paragraph
state = 2
elif state == 2:
if line.startswith('-'):
# We're looking at the break paragraph, so we're done
break
# At this point we know we must be looking at a recipient
# paragraph
mo = acre.match(line)
if mo:
addrs.append(mo.group('addr'))
# Otherwise, it must be a continuation line, so just ignore it
# Not looking at anything in particular
return addrs
