erebion/libervia-backend
Watch
1
0
Fork
You've already forked libervia-backend
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

plugin pte: Pubsub Target Encryption implementation:

Browse source 
This plugin lets encrypt a few items for a specific set of entities.

rel 382
This commit is contained in:
Goffi 2022-10-31 13:46:51 +01:00
commit e08d8207d6
3 changed files with 194 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

171
sat/plugins/plugin_sec_pte.py Normal file
View file

@ -0,0 +1,171 @@
#!/usr/bin/env python3
# Libervia plugin for Pubsub Targeted Encryption
# Copyright (C) 2009-2022 Jérôme Poisson (goffi@goffi.org)
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 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 Affero General Public License for more details.
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
from typing import Any, Dict, List, Optional
from twisted.internet import defer
from twisted.words.protocols.jabber import jid, xmlstream
from twisted.words.xish import domish
from wokkel import disco, iwokkel
from wokkel import rsm
from zope.interface import implementer
from sat.core import exceptions
from sat.core.constants import Const as C
from sat.core.core_types import SatXMPPEntity
from sat.core.i18n import _
from sat.core.log import getLogger
log = getLogger(__name__)
IMPORT_NAME = "PTE"
PLUGIN_INFO = {
C.PI_NAME: "Pubsub Targeted Encryption",
C.PI_IMPORT_NAME: IMPORT_NAME,
C.PI_TYPE: C.PLUG_TYPE_XEP,
C.PI_MODES: C.PLUG_MODE_BOTH,
C.PI_PROTOCOLS: [],
C.PI_DEPENDENCIES: ["XEP-0060", "XEP-0384"],
C.PI_MAIN: "PTE",
C.PI_HANDLER: "yes",
C.PI_DESCRIPTION: _("""Encrypt some items to specific entities"""),
}
NS_PTE = "urn:xmpp:pte:0"
class PTE:
namespace = NS_PTE
def __init__(self, host):
log.info(_("Pubsub Targeted Encryption plugin initialization"))
host.registerNamespace("pte", NS_PTE)
self.host = host
self._o = host.plugins["XEP-0384"]
host.trigger.add("XEP-0060_publish", self._publish_trigger)
host.trigger.add("XEP-0060_items", self._items_trigger)
def getHandler(self, client):
return PTE_Handler()
async def _publish_trigger(
self,
client: SatXMPPEntity,
service: jid.JID,
node: str,
items: Optional[List[domish.Element]],
options: Optional[dict],
sender: jid.JID,
extra: Dict[str, Any]
) -> bool:
if not items or extra.get("encrypted_for") is None:
return True
encrypt_data = extra["encrypted_for"]
try:
targets = {jid.JID(t) for t in encrypt_data["targets"]}
except (KeyError, RuntimeError):
raise exceptions.DataError(f"Invalid encryption data: {encrypt_data}")
for item in items:
log.debug(
f"encrypting item {item.getAttribute('id', '')} for "
f"{', '.join(t.full() for t in targets)}"
)
encryption_type = encrypt_data.get("type", self._o.NS_TWOMEMO)
if encryption_type != self._o.NS_TWOMEMO:
raise NotImplementedError("only TWOMEMO is supported for now")
await self._o.encrypt(
client,
self._o.NS_TWOMEMO,
item,
targets,
is_muc_message=False,
stanza_id=None
)
item_elts = list(item.elements())
if len(item_elts) != 1:
raise ValueError(
f"there should be exactly one item payload: {item.toXml()}"
)
encrypted_payload = item_elts[0]
item.children.clear()
encrypted_elt = item.addElement((NS_PTE, "encrypted"))
encrypted_elt["by"] = sender.userhost()
encrypted_elt["type"] = encryption_type
encrypted_elt.addChild(encrypted_payload)
return True
async def _items_trigger(
self,
client: SatXMPPEntity,
service: Optional[jid.JID],
node: str,
items: List[domish.Element],
rsm_response: rsm.RSMResponse,
extra: Dict[str, Any],
) -> bool:
if not extra.get(C.KEY_DECRYPT, True):
return True
if service is None:
service = client.jid.userhostJID()
for item in items:
payload = item.firstChildElement()
if (payload is not None
and payload.name == "encrypted"
and payload.uri == NS_PTE):
encrypted_elt = payload
item.children.clear()
try:
encryption_type = encrypted_elt.getAttribute("type")
encrypted_by = jid.JID(encrypted_elt["by"])
except (KeyError, RuntimeError):
raise exceptions.DataError(
f"invalid <encrypted> element: {encrypted_elt.toXml()}"
)
if encryption_type!= self._o.NS_TWOMEMO:
raise NotImplementedError("only TWOMEMO is supported for now")
log.debug(f"decrypting item {item.getAttribute('id', '')}")
# FIXME: we do use _message_received_trigger now to decrypt the stanza, a
# cleaner separated decrypt method should be used
encrypted_elt["from"] = encrypted_by.full()
if not await self._o._message_received_trigger(
client,
encrypted_elt,
defer.Deferred()
) or not encrypted_elt.children:
raise exceptions.EncryptionError("can't decrypt the message")
item.addChild(encrypted_elt.firstChildElement())
extra.setdefault("encrypted", {})[item["id"]] = {
"type": NS_PTE,
"algorithm": encryption_type
}
return True
@implementer(iwokkel.IDisco)
class PTE_Handler(xmlstream.XMPPHandler):
def getDiscoInfo(self, requestor, service, nodeIdentifier=""):
return [disco.DiscoFeature(NS_PTE)]
def getDiscoItems(self, requestor, service, nodeIdentifier=""):
return []

2
sat/plugins/plugin_xep_0277.py
View file

@ -984,7 +984,7 @@ class XEP_0277(object):
return None
extra = {}
for key in ("encrypted", "signed"):
for key in ("encrypted", "encrypted_for", "signed"):
value = data.get(key)
if value is not None:
extra[key] = value

35
sat/plugins/plugin_xep_0384.py
View file

@ -22,7 +22,7 @@ import enum
import logging
import time
from typing import \
Any, Dict, FrozenSet, List, Literal, NamedTuple, Optional, Set, Type, cast
Any, Dict, FrozenSet, List, Literal, NamedTuple, Optional, Set, Type, Union, cast
import uuid
import xml.etree.ElementTree as ET
from xml.sax.saxutils import quoteattr
@ -1581,7 +1581,7 @@ class OMEMO:
# added, the messageReceived trigger is also used for twomemo.
sat.trigger.add(
"messageReceived",
self.__message_received_trigger,
self._message_received_trigger,
priority=100050
)
sat.trigger.add(
@ -2098,7 +2098,7 @@ class OMEMO:
frozenset(applied_trust_updates)
)
async def __message_received_trigger(
async def _message_received_trigger(
self,
client: SatXMPPClient,
message_elt: domish.Element,
@ -2113,13 +2113,12 @@ class OMEMO:
encrypted.
@return: Whether to continue the message received flow.
"""
muc_plaintext_cache_key: Optional[MUCPlaintextCacheKey] = None
sender_jid = jid.JID(message_elt["from"])
feedback_jid: jid.JID
message_type = message_elt.getAttribute("type", "unknown")
message_type = message_elt.getAttribute("type", C.MESS_TYPE_NORMAL)
is_muc_message = message_type == C.MESS_TYPE_GROUPCHAT
if is_muc_message:
if self.__xep_0045 is None:
@ -2420,12 +2419,12 @@ class OMEMO:
return True
# All pre-checks done, we can start encrypting!
await self.__encrypt(
await self.encrypt(
client,
twomemo.twomemo.NAMESPACE,
stanza,
recipient_bare_jid,
stanza.getAttribute("type", "unkown") == C.MESS_TYPE_GROUPCHAT,
stanza.getAttribute("type", C.MESS_TYPE_NORMAL) == C.MESS_TYPE_GROUPCHAT,
stanza.getAttribute("id", None)
)
@ -2462,7 +2461,7 @@ class OMEMO:
is_muc_message = mess_data["type"] == C.MESS_TYPE_GROUPCHAT
stanza_id = mess_data["uid"]
await self.__encrypt(
await self.encrypt(
client,
oldmemo.oldmemo.NAMESPACE,
stanza,
@ -2474,12 +2473,12 @@ class OMEMO:
# Add a store hint
self.__xep_0334.addHintElements(stanza, [ "store" ])
async def __encrypt(
async def encrypt(
self,
client: SatXMPPClient,
namespace: Literal["urn:xmpp:omemo:2", "eu.siacs.conversations.axolotl"],
stanza: domish.Element,
recipient_jid: jid.JID,
recipient_jids: Union[jid.JID, Set[jid.JID]],
is_muc_message: bool,
stanza_id: Optional[str]
) -> None:
@ -2488,8 +2487,9 @@ class OMEMO:
@param namespace: The namespace of the OMEMO version to use.
@param stanza: The stanza. Twomemo will encrypt the whole stanza using SCE,
oldmemo will encrypt only the body. The stanza is modified by this call.
@param recipient_jid: The JID of the recipient. Can be a bare (aka "userhost") JID
but doesn't have to.
@param recipient_jid: The JID of the recipients.
Can be a bare (aka "userhost") JIDs but doesn't have to.
A single JID can be used.
@param is_muc_message: Whether the stanza is a message stanza to a MUC room.
@param stanza_id: The id of this stanza. Especially relevant for message stanzas
to MUC rooms such that the outgoing plaintext can be cached for MUC message
@ -2499,6 +2499,11 @@ class OMEMO:
hint to the stanza if applicable! This can be done before or after this call,
the order doesn't matter.
"""
if isinstance(recipient_jids, jid.JID):
recipient_jids = {recipient_jids}
if not recipient_jids:
raise exceptions.InternalError("At least one JID must be specified")
recipient_jid = next(iter(recipient_jids))
muc_plaintext_cache_key: Optional[MUCPlaintextCacheKey] = None
@ -2506,6 +2511,10 @@ class OMEMO:
feedback_jid: jid.JID
if is_muc_message:
if len(recipient_jids) != 1:
raise exceptions.InternalError(
'Only one JID can be set when "is_muc_message" is set'
)
if self.__xep_0045 is None:
raise exceptions.InternalError(
"Encryption of MUC message requested, but plugin XEP-0045 is not"
@ -2531,7 +2540,7 @@ class OMEMO:
message_uid=stanza_id
)
else:
recipient_bare_jids = { recipient_jid.userhost() }
recipient_bare_jids = {r.userhost() for r in recipient_jids}
feedback_jid = recipient_jid.userhostJID()
log.debug(