Files
gajim-plugins/pgp/backend/python_gnupg.py
wurstsalat db0a0d1118 [pgp] 1.5.1
Fix Singleton import
2023-01-07 22:50:14 +01:00

154 lines
4.9 KiB
Python

# Copyright (C) 2019 Philipp Hörist <philipp AT hoerist.com>
# Copyright (C) 2003-2014 Yann Leboulanger <asterix AT lagaule.org>
# Copyright (C) 2005 Alex Mauer <hawke AT hawkesnest.net>
# Copyright (C) 2005-2006 Nikos Kouremenos <kourem AT gmail.com>
# Copyright (C) 2007 Stephan Erb <steve-e AT h3c.de>
# Copyright (C) 2008 Jean-Marie Traissard <jim AT lapin.org>
# Jonathan Schleifer <js-gajim AT webkeks.org>
#
# This file is part of PGP Gajim Plugin.
#
# PGP Gajim Plugin 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; version 3 only.
#
# PGP Gajim Plugin 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 PGP Gajim Plugin. If not, see <http://www.gnu.org/licenses/>.
import os
import logging
from functools import lru_cache
import gnupg
from gajim.common.util.classes import Singleton
from pgp.exceptions import SignError
logger = logging.getLogger('gajim.p.pgplegacy')
if logger.getEffectiveLevel() == logging.DEBUG:
logger = logging.getLogger('gnupg')
logger.addHandler(logging.StreamHandler())
logger.setLevel(logging.DEBUG)
class PGP(gnupg.GPG, metaclass=Singleton):
def __init__(self, binary, encoding=None):
super().__init__(gpgbinary=binary,
use_agent=True)
if encoding is not None:
self.encoding = encoding
self.decode_errors = 'replace'
def encrypt(self, payload, recipients, always_trust=False):
if not always_trust:
# check that we'll be able to encrypt
result = self.get_key(recipients[0])
for key in result:
if key['trust'] not in ('f', 'u'):
return '', 'NOT_TRUSTED ' + key['keyid'][-8:]
result = super().encrypt(
payload.encode('utf8'),
recipients,
always_trust=always_trust)
if result.ok:
error = ''
else:
error = result.status
return self._strip_header_footer(str(result)), error
def decrypt(self, payload):
data = self._add_header_footer(payload, 'MESSAGE')
result = super().decrypt(data.encode('utf8'))
return result.data.decode('utf8')
@lru_cache(maxsize=8)
def sign(self, payload, key_id):
if payload is None:
payload = ''
result = super().sign(payload.encode('utf8'),
keyid=key_id,
detach=True)
if result.fingerprint:
return self._strip_header_footer(str(result))
raise SignError(result.status)
def verify(self, payload, signed):
# Hash algorithm is not transfered in the signed
# presence stanza so try all algorithms.
# Text name for hash algorithms from RFC 4880 - section 9.4
if payload is None:
payload = ''
hash_algorithms = ['SHA512', 'SHA384', 'SHA256',
'SHA224', 'SHA1', 'RIPEMD160']
for algo in hash_algorithms:
data = os.linesep.join(
['-----BEGIN PGP SIGNED MESSAGE-----',
'Hash: ' + algo,
'',
payload,
self._add_header_footer(signed, 'SIGNATURE')]
)
result = super().verify(data.encode('utf8'))
if result.valid:
return result.fingerprint
def get_key(self, key_id):
return super().list_keys(keys=[key_id])
def get_keys(self, secret=False):
keys = {}
result = super().list_keys(secret=secret)
for key in result:
# Take first not empty uid
keys[key['fingerprint']] = next(uid for uid in key['uids'] if uid)
return keys
@staticmethod
def _strip_header_footer(data):
"""
Remove header and footer from data
"""
if not data:
return ''
lines = data.splitlines()
while lines[0] != '':
lines.remove(lines[0])
while lines[0] == '':
lines.remove(lines[0])
i = 0
for line in lines:
if line:
if line[0] == '-':
break
i = i+1
line = '\n'.join(lines[0:i])
return line
@staticmethod
def _add_header_footer(data, type_):
"""
Add header and footer from data
"""
out = "-----BEGIN PGP %s-----" % type_ + os.linesep
out = out + "Version: PGP" + os.linesep
out = out + os.linesep
out = out + data + os.linesep
out = out + "-----END PGP %s-----" % type_ + os.linesep
return out