#!/usr/bin/env python

# mailman-openssl-smime.py - demo on how to deal with smime messages in
#  the Mailman framework, using the SMIMEUtils module which calls the
#  openssl command line tool
#
# based upon smime handling found in sympa-5.1/src/tools.pl , from
#   http://www.sympa.org/distribution/
#
# usage: this script should get installed in mailman/bin.  On Debian
#  GNU/Linux systems this is /usr/lib/mailman/bin/ .  It reads a raw S/MIME
#  message on stdin.

# Copyright (C) 2005 Tilburg University http://www.uvt.nl/
# Author: Joost van Baal
#
#    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

import paths
from Mailman import mm_cfg
import sys
import email
import os
# import time # for sleep

sys.path.append('/usr/lib/mailman/Mailman/Handlers')
sys.path.append('/usr/lib/mailman/Mailman/')

import Utils
from Mailman import Message
from Mailman import SMIMEUtils

msg = email.message_from_string(sys.stdin.read(), Message.Message)

from MailList import MailList
mlist = MailList('test-smime', lock=False)

#  import pickle
#  mlist = pickle.load(open('/var/lib/mailman/lists/test-smime/config.pck'))
# smime list stuff in:
# /var/lib/mailman/lists/<listname>/smime/{key,cert}.pem

sm = SMIMEUtils.SMIMEHelper(mlist)

if msg.is_multipart():
    if sm.verifyMessage(msg):
        print "S/MIME verify OK"
    else:
        print "S/MIME verify failed"
elif msg.get_content_type()=="application/x-pkcs7-mime":

        ciphertext = msg.as_string()

        (plaintext,key_ids) = sm.decryptMessage(ciphertext)

        print "sm.decryptMessage returned:"
        print plaintext

        # the plaintext could be signed s/mime stuff!
        # it could e.g. look like:

        # Content-Type: multipart/signed; protocol="application/x-pkcs7-signature";
        #         micalg=sha1; boundary="ZfOjI3PrQbgiZnxM"
        # Content-Disposition: inline
        # 
        # 
        # --ZfOjI3PrQbgiZnxM
        # Content-Type: text/plain; charset=us-ascii
        # Content-Disposition: inline
        # Content-Transfer-Encoding: quoted-printable
        # 
        # blah
        # 
        # --=20
        # Joost van Baal                                       joostvb@uvt.nl
        # http://abramowitz.uvt.nl/                            (013-466-)3519
        #
        # --ZfOjI3PrQbgiZnxM
        # Content-Type: application/x-pkcs7-signature
        # Content-Disposition: attachment; filename="smime.p7s"
        # Content-Transfer-Encoding: base64
        #
        # MIILmQYJKoZIhvcNAQcCoIILijCCC4YCAQExCzAJBgUrDgMCGgUAMAsGCSqGSIb3DQEHAaCC
        # COowggQ8MIIDJKADAgECAhEAgyFoZDtGClKLMxBBT6SYNDANBgkqhkiG9w0BAQUFADCBhTEL

else:
    # assume stdin is just some blob of data.  let's encrypt it.
    recipfile = sm.getSMIMEMemberCertFile("j.e.vanbaal@uvt.nl")
    ciphertext = sm.encryptMessage(msg.as_string(), recipfile)
    print "sm.encryptMessage returned:"
    print ciphertext

    ciphertext = sm.encryptSignMessage(msg.as_string(), recipfile)
    print "sm.encryptSignMessage returned:"
    print ciphertext

# The only way to control the input and output streams and
# also retrieve the return codes is to use the Popen3 and Popen4 classes from
# the popen2 module; these are only available on Unix.
#
# os.system doesn't do it for us: we need to fiddle with std{in,out,err}

# Let's see if our openssl calls really terminate.
# If not, we'll see something like
#  joostvb   3857  0.5  0.2  7868 5480 pts/1    S+   16:39   0:00  \_ python ./mailman-openssl-smime.py
#  joostvb   3858  0.0  0.0     0    0 pts/1    Z+   16:39   0:00      \_ [openssl] <defunct>
# verify, decrypt and encrypt show this!

## os.wait()  # reap our children

### import time     # for sleep
### time.sleep(300) # give some time to inspect ps status