]> gitweb.pimeys.fr Git - scripts-20-100.git/blob - clearmime.py
[update_myscripts] bde-fallback plus clair que bde2
[scripts-20-100.git] / clearmime.py
1 #!/usr/bin/python
2
3 # Copyright 2008 Lenny Domnitser <http://domnit.org/>
4 #
5 # This program is free software; you can redistribute it and/or modify
6 # it under the terms of the GNU General Public License as published by
7 # the Free Software Foundation; either version 3 of the License, or (at
8 # your option) any later version.
9 #
10 # This program is distributed in the hope that it will be useful, but
11 # WITHOUT ANY WARRANTY; without even the implied warranty of
12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 # General Public License for more details.
14 #
15 # You should have received a copy of the GNU General Public License
16 # along with this program. If not, see <http://www.gnu.org/licenses/>.
17
18 __all__ = 'clarify',
19 __author__ = 'Lenny Domnitser'
20 __version__ = '0.1'
21
22 import email
23 import re
24
25 TEMPLATE = '''-----BEGIN PGP SIGNED MESSAGE-----
26 Hash: %(hashname)s
27 NotDashEscaped: You need GnuPG to verify this message
28
29 %(text)s%(sig)s'''
30
31
32 def _clarify(message, messagetext):
33 if message.get_content_type() == 'multipart/signed':
34 if message.get_param('protocol') == 'application/pgp-signature':
35 hashname = message.get_param('micalg').upper()
36 assert hashname.startswith('PGP-')
37 hashname = hashname.replace('PGP-', '', 1)
38 textmess, sigmess = message.get_payload()
39 assert sigmess.get_content_type() == 'application/pgp-signature'
40 #text = textmess.as_string() - not byte-for-byte accurate
41 text = messagetext.split('\n--%s\n' % message.get_boundary(), 2)[1]
42 sig = sigmess.get_payload()
43 assert isinstance(sig, str)
44 # Setting content-type to application/octet instead of text/plain
45 # to maintain CRLF endings. Using replace_header instead of
46 # set_type because replace_header clears parameters.
47 message.replace_header('Content-Type', 'application/octet')
48 clearsign = TEMPLATE % locals()
49 clearsign = clearsign.replace(
50 '\r\n', '\n').replace('\r', '\n').replace('\n', '\r\n')
51 message.set_payload(clearsign)
52 elif message.is_multipart():
53 for message in message.get_payload():
54 _clarify(message, messagetext)
55
56
57 def clarify(messagetext):
58 '''given a string containing a MIME message, returns a string
59 where PGP/MIME messages are replaced with clearsigned messages.'''
60
61 message = email.message_from_string(messagetext)
62 _clarify(message, messagetext)
63 return message.as_string()
64
65
66 if __name__ == '__main__':
67 import sys
68 sys.stdout.write(clarify(sys.stdin.read()))
69