annotate sat/plugins/plugin_sec_aesgcm.py @ 3162:b5c058c7692e

core (xmpp), plugin android: fixed DNS, SRV handling on Android: Android doesn't have a "/etc/resolv.conf" that Twisted expect. As a result, SRV records can't be checked correctly on connection. To work around that, DNS servers used on Android are checked when necessary (on Android plugin startup and on connectivity change), using some hacks, and Twisted is patched to use them.
author Goffi <goffi@goffi.org>
date Sun, 09 Feb 2020 23:56:42 +0100
parents 9d0df638c8b4
children c90f27ce52b0
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
3090
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
1 #!/usr/bin/env python3
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
2
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
3 # SAT plugin for handling AES-GCM file encryption
3136
9d0df638c8b4 dates update
Goffi <goffi@goffi.org>
parents: 3090
diff changeset
4 # Copyright (C) 2009-2020 Jérôme Poisson (goffi@goffi.org)
3090
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
5
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
6 # This program is free software: you can redistribute it and/or modify
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
7 # it under the terms of the GNU Affero General Public License as published by
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
8 # the Free Software Foundation, either version 3 of the License, or
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
9 # (at your option) any later version.
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
10
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
11 # This program is distributed in the hope that it will be useful,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
14 # GNU Affero General Public License for more details.
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
15
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
16 # You should have received a copy of the GNU Affero General Public License
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
17 # along with this program. If not, see <http://www.gnu.org/licenses/>.
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
18
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
19 from textwrap import dedent
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
20 from functools import partial
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
21 import secrets
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
22 from cryptography.hazmat.primitives import ciphers
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
23 from cryptography.hazmat.primitives.ciphers import modes
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
24 from cryptography.hazmat import backends
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
25 from cryptography.exceptions import AlreadyFinalized
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
26 from urllib import parse
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
27 import treq
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
28 from sat.core.i18n import _
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
29 from sat.core.constants import Const as C
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
30 from sat.core import exceptions
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
31 from sat.tools import stream
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
32 from sat.core.log import getLogger
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
33
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
34 log = getLogger(__name__)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
35
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
36 PLUGIN_INFO = {
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
37 C.PI_NAME: "AES-GCM",
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
38 C.PI_IMPORT_NAME: "AES-GCM",
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
39 C.PI_TYPE: "SEC",
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
40 C.PI_PROTOCOLS: ["OMEMO Media sharing"],
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
41 C.PI_DEPENDENCIES: ["XEP-0363", "XEP-0384", "DOWNLOAD"],
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
42 C.PI_MAIN: "AESGCM",
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
43 C.PI_HANDLER: "no",
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
44 C.PI_DESCRIPTION: dedent(_("""\
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
45 Implementation of AES-GCM scheme, a way to encrypt files (not official XMPP standard).
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
46 See https://xmpp.org/extensions/inbox/omemo-media-sharing.html for details
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
47 """)),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
48 }
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
49
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
50
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
51 class AESGCM(object):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
52
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
53 def __init__(self, host):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
54 self.host = host
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
55 log.info(_("AESGCM plugin initialization"))
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
56 host.plugins["DOWNLOAD"].registerScheme(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
57 "aesgcm", self.download
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
58 )
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
59 host.trigger.add("XEP-0363_upload_size", self._uploadSizeTrigger)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
60 host.trigger.add("XEP-0363_upload", self._uploadTrigger)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
61
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
62 async def download(self, client, uri_parsed, dest_path, options):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
63 fragment = bytes.fromhex(uri_parsed.fragment)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
64
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
65 # legacy method use 16 bits IV, but OMEMO media sharing published spec indicates
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
66 # which is 12 bits IV (AES-GCM spec recommandation), so we have to determine
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
67 # which size has been used.
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
68 if len(fragment) == 48:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
69 iv_size = 16
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
70 elif len(fragment) == 44:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
71 iv_size = 12
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
72 else:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
73 raise ValueError(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
74 f"Invalid URL fragment, can't decrypt file at {uri_parsed.get_url()}")
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
75
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
76 iv, key = fragment[:iv_size], fragment[iv_size:]
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
77
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
78 decryptor = ciphers.Cipher(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
79 ciphers.algorithms.AES(key),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
80 modes.GCM(iv),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
81 backend=backends.default_backend(),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
82 ).decryptor()
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
83
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
84 download_url = parse.urlunparse(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
85 ('https', uri_parsed.netloc, uri_parsed.path, '', '', ''))
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
86
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
87 head_data = await treq.head(download_url)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
88 content_length = int(head_data.headers.getRawHeaders('content-length')[0])
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
89 # the 128 bits tag is put at the end
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
90 file_size = content_length - 16
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
91
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
92 file_obj = stream.SatFile(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
93 self.host,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
94 client,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
95 dest_path,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
96 mode="wb",
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
97 size = file_size,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
98 )
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
99
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
100 progress_id = file_obj.uid
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
101
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
102 resp = await treq.get(download_url, unbuffered=True)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
103 d = treq.collect(resp, partial(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
104 self.onDataDownload,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
105 client=client,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
106 file_obj=file_obj,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
107 decryptor=decryptor))
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
108 return progress_id, d
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
109
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
110 def onDataDownload(self, data, client, file_obj, decryptor):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
111 if file_obj.tell() + len(data) > file_obj.size:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
112 # we're reaching end of file with this bunch of data
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
113 # we may still have a last bunch if the tag is incomplete
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
114 bytes_left = file_obj.size - file_obj.tell()
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
115 if bytes_left > 0:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
116 decrypted = decryptor.update(data[:bytes_left])
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
117 file_obj.write(decrypted)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
118 tag = data[bytes_left:]
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
119 else:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
120 tag = data
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
121 if len(tag) < 16:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
122 # the tag is incomplete, either we'll get the rest in next data bunch
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
123 # or we have already the other part from last bunch of data
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
124 try:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
125 # we store partial tag in decryptor._sat_tag
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
126 tag = decryptor._sat_tag + tag
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
127 except AttributeError:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
128 # no other part, we'll get the rest at next bunch
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
129 decryptor.sat_tag = tag
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
130 else:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
131 # we have the complete tag, it must be 128 bits
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
132 if len(tag) != 16:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
133 raise ValueError(f"Invalid tag: {tag}")
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
134 remain = decryptor.finalize_with_tag(tag)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
135 file_obj.write(remain)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
136 file_obj.close()
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
137 else:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
138 decrypted = decryptor.update(data)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
139 file_obj.write(decrypted)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
140
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
141 def _uploadSizeTrigger(self, client, options, file_path, size, size_adjust):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
142 if options.get('encryption') != C.ENC_AES_GCM:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
143 return True
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
144 # the tag is appended to the file
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
145 size_adjust.append(16)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
146 return True
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
147
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
148 def _encrypt(self, data, encryptor):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
149 if data:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
150 return encryptor.update(data)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
151 else:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
152 try:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
153 # end of file is reached, me must finalize
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
154 ret = encryptor.finalize()
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
155 tag = encryptor.tag
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
156 return ret + tag
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
157 except AlreadyFinalized:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
158 # as we have already finalized, we can now send EOF
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
159 return b''
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
160
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
161 def _uploadTrigger(self, client, options, sat_file, file_producer, slot):
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
162 if options.get('encryption') != C.ENC_AES_GCM:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
163 return True
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
164 log.debug("encrypting file with AES-GCM")
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
165 # specification talks about 12 bytes IV, but in practice and for legacy reasons
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
166 # 16 bytes are used by most clients (and also in the specification example).
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
167 # It seems that some clients don't handle 12 bytes IV (apparently,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
168 # that's the case for ChatSecure).
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
169 # So we have to follow the de-facto standard and use 16 bytes to be sure
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
170 # to be compatible with a maximum of clients.
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
171 iv = secrets.token_bytes(16)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
172 key = secrets.token_bytes(32)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
173 fragment = f'{iv.hex()}{key.hex()}'
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
174 ori_url = parse.urlparse(slot.get)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
175 # we change the get URL with the one with aesgcm scheme and containing the
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
176 # encoded key + iv
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
177 slot.get = parse.urlunparse(['aesgcm', *ori_url[1:5], fragment])
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
178
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
179 # encrypted data size will be bigger than original file size
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
180 # so we need to check with final data length to avoid a warning on close()
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
181 sat_file.check_size_with_read = True
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
182
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
183 # file_producer get length directly from file, and this cause trouble has
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
184 # we have to change the size because of encryption. So we adapt it here,
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
185 # else the producer would stop reading prematurely
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
186 file_producer.length = sat_file.size
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
187
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
188 encryptor = ciphers.Cipher(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
189 ciphers.algorithms.AES(key),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
190 modes.GCM(iv),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
191 backend=backends.default_backend(),
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
192 ).encryptor()
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
193
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
194 if sat_file.data_cb is not None:
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
195 raise exceptions.InternalError(
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
196 f"data_cb was expected to be None, it is set to {sat_file.data_cb}")
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
197
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
198 # with data_cb we encrypt the file on the fly
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
199 sat_file.data_cb = partial(self._encrypt, encryptor=encryptor)
4f8bdf50593f plugin sec aesgcm: new plugin handling `aesgcm:` scheme for e2e encrypted media sharing:
Goffi <goffi@goffi.org>
parents:
diff changeset
200 return True