libervia-backend: sat/plugins/plugin_xep

author	Syndace <me@syndace.dev>
date	Tue, 23 Aug 2022 12:04:11 +0200
parents
children	8289ac1b34f4

rev	line source
3877 00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	1 #!/usr/bin/env python3
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	2
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	3 # Libervia plugin for Stanza Content Encryption
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	4 # Copyright (C) 2022-2022 Tim Henkes (me@syndace.dev)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	5
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	6 # This program is free software: you can redistribute it and/or modify
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	7 # it under the terms of the GNU Affero General Public License as published by
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	8 # the Free Software Foundation, either version 3 of the License, or
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	9 # (at your option) any later version.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	10
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	11 # This program is distributed in the hope that it will be useful,
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	14 # GNU Affero General Public License for more details.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	15
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	16 # You should have received a copy of the GNU Affero General Public License
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	17 # along with this program. If not, see <http://www.gnu.org/licenses/>.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	18
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	19 # Type-check with `mypy --strict --disable-error-code no-untyped-call`
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	20 # Lint with `pylint`
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	21
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	22 from abc import ABC, abstractmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	23 from datetime import datetime
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	24 import enum
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	25 import secrets
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	26 import string
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	27 from typing import Dict, Iterator, List, NamedTuple, Optional, Set, Tuple, Union, cast
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	28
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	29 from lxml import etree
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	30
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	31 from sat.core.constants import Const as C
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	32 from sat.core.i18n import D_
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	33 from sat.core.log import Logger, getLogger
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	34 from sat.core.sat_main import SAT
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	35 from sat.tools.xml_tools import ElementParser
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	36 from sat.plugins.plugin_xep_0033 import NS_ADDRESS
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	37 from sat.plugins.plugin_xep_0082 import XEP_0082
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	38 from sat.plugins.plugin_xep_0334 import NS_HINTS
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	39 from sat.plugins.plugin_xep_0359 import NS_SID
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	40 from sat.plugins.plugin_xep_0380 import NS_EME
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	41 from twisted.words.protocols.jabber import jid
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	42 from twisted.words.xish import domish
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	43
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	44
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	45 __all__ = [ # pylint: disable=unused-variable
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	46 "PLUGIN_INFO",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	47 "NS_SCE",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	48 "XEP_0420",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	49 "ProfileRequirementsNotMet",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	50 "AffixVerificationFailed",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	51 "SCECustomAffix",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	52 "SCEAffixPolicy",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	53 "SCEProfile",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	54 "SCEAffixValues"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	55 ]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	56
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	57
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	58 log = cast(Logger, getLogger(__name__))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	59
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	60
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	61 PLUGIN_INFO = {
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	62 C.PI_NAME: "SCE",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	63 C.PI_IMPORT_NAME: "XEP-0420",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	64 C.PI_TYPE: "SEC",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	65 C.PI_PROTOCOLS: [ "XEP-0420" ],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	66 C.PI_DEPENDENCIES: [ "XEP-0334", "XEP-0082" ],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	67 C.PI_RECOMMENDATIONS: [ "XEP-0045", "XEP-0033", "XEP-0359" ],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	68 C.PI_MAIN: "XEP_0420",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	69 C.PI_HANDLER: "no",
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	70 C.PI_DESCRIPTION: D_("Implementation of Stanza Content Encryption"),
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	71 }
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	72
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	73
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	74 NS_SCE = "urn:xmpp:sce:1"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	75
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	76
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	77 class ProfileRequirementsNotMet(Exception):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	78 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	79 Raised by :meth:`XEP_0420.unpack_stanza` in case the requirements formulated by the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	80 profile are not met.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	81 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	82
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	83
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	84 class AffixVerificationFailed(Exception):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	85 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	86 Raised by :meth:`XEP_0420.unpack_stanza` in case of affix verification failure.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	87 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	88
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	89
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	90 class SCECustomAffix(ABC):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	91 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	92 Interface for custom affixes of SCE profiles.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	93 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	94
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	95 @property
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	96 @abstractmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	97 def element_name(self) -> str:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	98 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	99 @return: The name of the affix's XML element.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	100 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	101
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	102 @property
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	103 @abstractmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	104 def element_schema(self) -> str:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	105 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	106 @return: The XML schema definition of the affix element's XML structure, i.e. the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	107 ``<xs:element/>`` schema element. This element will be referenced using
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	108 ``<xs:element ref="{element_name}"/>``.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	109 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	110
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	111 @abstractmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	112 def create(self, stanza: domish.Element) -> domish.Element:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	113 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	114 @param stanza: The stanza element which has been processed by
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	115 :meth:`XEP_0420.pack_stanza`, i.e. all encryptable children have been removed
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	116 and only the root ``<message/>`` or ``<iq/>`` and unencryptable children
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	117 remain. Do not modify.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	118 @return: An affix element to include in the envelope. The element must have the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	119 name :attr:`element_name` and must validate using :attr:`element_schema`.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	120 @raise ValueError: if the affix couldn't be built.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	121 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	122
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	123 @abstractmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	124 def verify(self, stanza: domish.Element, element: domish.Element) -> None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	125 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	126 @param stanza: The stanza element before being processed by
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	127 :meth:`XEP_0420.unpack_stanza`, i.e. all encryptable children have been
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	128 removed and only the root ``<message/>`` or ``<iq/>`` and unencryptable
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	129 children remain. Do not modify.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	130 @param element: The affix element to verify.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	131 @raise AffixVerificationFailed: on verification failure.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	132 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	133
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	134
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	135 @enum.unique
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	136 class SCEAffixPolicy(enum.Enum):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	137 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	138 Policy for the presence of an affix in an SCE envelope.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	139 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	140
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	141 REQUIRED: str = "REQUIRED"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	142 OPTIONAL: str = "OPTIONAL"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	143 NOT_NEEDED: str = "NOT_NEEDED"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	144
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	145
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	146 class SCEProfile(NamedTuple):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	147 # pylint: disable=invalid-name
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	148 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	149 An SCE profile, i.e. the definition which affixes are required, optional or not needed
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	150 at all by an SCE-enabled encryption protocol.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	151 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	152
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	153 rpad_policy: SCEAffixPolicy
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	154 time_policy: SCEAffixPolicy
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	155 to_policy: SCEAffixPolicy
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	156 from_policy: SCEAffixPolicy
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	157 custom_policies: Dict[SCECustomAffix, SCEAffixPolicy]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	158
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	159
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	160 class SCEAffixValues(NamedTuple):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	161 # pylint: disable=invalid-name
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	162 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	163 Structure returned by :meth:`XEP_0420.unpack_stanza` with the parsed/processes values
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	164 of all affixes included in the envelope. For custom affixes, the whole affix element
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	165 is returned.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	166 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	167
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	168 rpad: Optional[str]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	169 timestamp: Optional[datetime]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	170 recipient: Optional[jid.JID]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	171 sender: Optional[jid.JID]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	172 custom: Dict[SCECustomAffix, domish.Element]
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	173
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	174
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	175 ENVELOPE_SCHEMA = """<?xml version="1.0" encoding="utf8"?>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	176 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	177 targetNamespace="urn:xmpp:sce:1"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	178 xmlns="urn:xmpp:sce:1">
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	179
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	180 <xs:element name="envelope">
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	181 <xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	182 <xs:all>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	183 <xs:element ref="content"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	184 <xs:element ref="rpad" minOccurs="0"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	185 <xs:element ref="time" minOccurs="0"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	186 <xs:element ref="to" minOccurs="0"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	187 <xs:element ref="from" minOccurs="0"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	188 {custom_affix_references}
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	189 </xs:all>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	190 </xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	191 </xs:element>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	192
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	193 <xs:element name="content">
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	194 <xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	195 <xs:sequence>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	196 <xs:any minOccurs="0" maxOccurs="unbounded" processContents="skip"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	197 </xs:sequence>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	198 </xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	199 </xs:element>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	200
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	201 <xs:element name="rpad" type="xs:string"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	202
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	203 <xs:element name="time">
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	204 <xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	205 <xs:attribute name="stamp" type="xs:dateTime"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	206 </xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	207 </xs:element>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	208
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	209 <xs:element name="to">
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	210 <xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	211 <xs:attribute name="jid" type="xs:string"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	212 </xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	213 </xs:element>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	214
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	215 <xs:element name="from">
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	216 <xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	217 <xs:attribute name="jid" type="xs:string"/>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	218 </xs:complexType>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	219 </xs:element>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	220
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	221 {custom_affix_definitions}
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	222 </xs:schema>
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	223 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	224
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	225
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	226 class XEP_0420: # pylint: disable=invalid-name
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	227 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	228 Implementation of XEP-0420: Stanza Content Encryption under namespace
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	229 ``urn:xmpp:sce:1``.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	230
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	231 This is a passive plugin, i.e. it doesn't hook into any triggers to process stanzas
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	232 actively, but offers API for other plugins to use.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	233 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	234
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	235 # Set of namespaces whose elements are never allowed to be transferred in an encrypted
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	236 # envelope.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	237 MUST_BE_PLAINTEXT_NAMESPACES: Set[str] = {
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	238 NS_HINTS,
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	239 NS_SID, # TODO: Not sure whether this ban applies to both stanza-id and origin-id
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	240 NS_ADDRESS,
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	241 # Not part of the specification (yet), but just doesn't make sense in an encrypted
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	242 # envelope:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	243 NS_EME
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	244 }
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	245
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	246 # Set of (namespace, element name) tuples that define elements which are never allowed
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	247 # to be transferred in an encrypted envelope. If all elements under a certain
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	248 # namespace are forbidden, the namespace can be added to
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	249 # :attr:`MUST_BE_PLAINTEXT_NAMESPACES` instead.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	250 # Note: only full namespaces are forbidden by the spec for now, the following is for
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	251 # potential future use.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	252 MUST_BE_PLAINTEXT_ELEMENTS: Set[Tuple[str, str]] = set()
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	253
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	254 def __init__(self, sat: SAT) -> None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	255 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	256 @param sat: The SAT instance.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	257 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	258
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	259 @staticmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	260 def pack_stanza(profile: SCEProfile, stanza: domish.Element) -> bytes:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	261 """Pack a stanza according to Stanza Content Encryption.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	262
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	263 Removes all elements from the stanza except for a few exceptions that explicitly
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	264 need to be transferred in plaintext, e.g. because they contain hints/instructions
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	265 for the server on how to process the stanza. Together with the affix elements as
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	266 requested by the profile, the removed elements are added to an envelope XML
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	267 structure that builds the plaintext to be encrypted by the SCE-enabled encryption
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	268 scheme. Optional affixes are always added to the structure, i.e. they are treated
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	269 by the packing code as if they were required.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	270
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	271 Once built, the envelope structure is serialized to a byte string and returned for
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	272 the encryption scheme to encrypt and add to the stanza.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	273
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	274 @param profile: The SCE profile, i.e. the definition of affixes to include in the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	275 envelope.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	276 @param stanza: The stanza to process. Will be modified by the call.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	277 @return: The serialized envelope structure that builds the plaintext for the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	278 encryption scheme to process.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	279 @raise ValueError: if the <to/> or <from/> affixes are requested but the stanza
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	280 doesn't have the "to"/"from" attribute set to extract the value from. Can also
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	281 be raised by custom affixes.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	282
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	283 @warning: It is up to the calling code to add a <store/> message processing hint
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	284 if applicable.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	285 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	286
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	287 # Prepare the envelope and content elements
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	288 envelope = domish.Element((NS_SCE, "envelope"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	289 content = envelope.addElement((NS_SCE, "content"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	290
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	291 # Note the serialized byte size of the content element before adding any children
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	292 empty_content_byte_size = len(content.toXml().encode("utf-8"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	293
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	294 # Just for type safety
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	295 stanza_children = cast(List[Union[domish.Element, str]], stanza.children)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	296 content_children = cast(List[Union[domish.Element, str]], content.children)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	297
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	298 # Move elements that are not explicitly forbidden from being encrypted from the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	299 # stanza to the content element.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	300 for child in list(cast(Iterator[domish.Element], stanza.elements())):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	301 if (
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	302 child.uri not in XEP_0420.MUST_BE_PLAINTEXT_NAMESPACES
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	303 and (child.uri, child.name) not in XEP_0420.MUST_BE_PLAINTEXT_ELEMENTS
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	304 ):
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	305 # Remove the child from the stanza
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	306 stanza_children.remove(child)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	307
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	308 # A namespace of ``None`` can be used on domish elements to inherit the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	309 # namespace from the parent. When moving elements from the stanza root to
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	310 # the content element, however, we don't want elements to inherit the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	311 # namespace of the content element. Thus, check for elements with ``None``
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	312 # for their namespace and set the namespace to jabber:client, which is the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	313 # namespace of the parent element.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	314 if child.uri is None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	315 child.uri = C.NS_CLIENT
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	316 child.defaultUri = C.NS_CLIENT
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	317
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	318 # Add the child with corrected namespaces to the content element
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	319 content_children.append(child)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	320
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	321 # Add the affixes requested by the profile
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	322 if profile.rpad_policy is not SCEAffixPolicy.NOT_NEEDED:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	323 # The specification defines the rpad affix to contain "[...] a randomly
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	324 # generated sequence of random length between 0 and 200 characters." This
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	325 # implementation differs a bit from the specification in that a minimum size
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	326 # other than 0 is chosen depending on the serialized size of the content
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	327 # element. This is to prevent the scenario where the encrypted content is
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	328 # short and the rpad is also randomly chosen to be short, which could allow
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	329 # guessing the content of a short message. To do so, the rpad length is first
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	330 # chosen to pad the content to at least 53 bytes, then afterwards another 0 to
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	331 # 200 bytes are added. Note that single-byte characters are used by this
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	332 # implementation, thus the number of characters equals the number of bytes.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	333 content_byte_size = len(content.toXml().encode("utf-8"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	334 content_byte_size_diff = content_byte_size - empty_content_byte_size
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	335 rpad_length = max(0, 53 - content_byte_size_diff) + secrets.randbelow(201)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	336 rpad_content = "".join(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	337 secrets.choice(string.digits + string.ascii_letters + string.punctuation)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	338 for __
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	339 in range(rpad_length)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	340 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	341 envelope.addElement((NS_SCE, "rpad"), content=rpad_content)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	342
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	343 if profile.time_policy is not SCEAffixPolicy.NOT_NEEDED:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	344 time_element = envelope.addElement((NS_SCE, "time"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	345 time_element["stamp"] = XEP_0082.format_datetime()
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	346
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	347 if profile.to_policy is not SCEAffixPolicy.NOT_NEEDED:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	348 recipient = cast(Optional[str], stanza.getAttribute("to", None))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	349 if recipient is None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	350 raise ValueError(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	351 "<to/> affix requested, but stanza doesn't have the 'to' attribute"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	352 " set."
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	353 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	354
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	355 to_element = envelope.addElement((NS_SCE, "to"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	356 to_element["jid"] = jid.JID(recipient).userhost()
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	357
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	358 if profile.from_policy is not SCEAffixPolicy.NOT_NEEDED:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	359 sender = cast(Optional[str], stanza.getAttribute("from", None))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	360 if sender is None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	361 raise ValueError(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	362 "<from/> affix requested, but stanza doesn't have the 'from'"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	363 " attribute set."
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	364 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	365
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	366 from_element = envelope.addElement((NS_SCE, "from"))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	367 from_element["jid"] = jid.JID(sender).userhost()
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	368
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	369 for affix, policy in profile.custom_policies.items():
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	370 if policy is not SCEAffixPolicy.NOT_NEEDED:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	371 envelope.addChild(affix.create(stanza))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	372
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	373 return cast(str, envelope.toXml()).encode("utf-8")
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	374
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	375 @staticmethod
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	376 def unpack_stanza(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	377 profile: SCEProfile,
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	378 stanza: domish.Element,
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	379 envelope_serialized: bytes
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	380 ) -> SCEAffixValues:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	381 """Unpack a stanza packed according to Stanza Content Encryption.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	382
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	383 Parses the serialized envelope as XML, verifies included affixes and makes sure
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	384 the requirements of the profile are met, and restores the stanza by moving
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	385 decrypted elements from the envelope back to the stanza top level.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	386
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	387 @param profile: The SCE profile, i.e. the definition of affixes that have to/may
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	388 be included in the envelope.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	389 @param stanza: The stanza to process. Will be modified by the call.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	390 @param envelope_serialized: The serialized envelope, i.e. the plaintext produced
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	391 by the decryption scheme utilizing SCE.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	392 @return: The parsed and processed values of all affixes that were present on the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	393 envelope, notably including the timestamp.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	394 @raise ValueError: if the serialized envelope element is malformed.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	395 @raise ProfileRequirementsNotMet: if one or more affixes required by the profile
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	396 are missing from the envelope.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	397 @raise AffixVerificationFailed: if an affix included in the envelope fails to
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	398 validate. It doesn't matter whether the affix is required by the profile or
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	399 not, all affixes included in the envelope are validated and cause this
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	400 exception to be raised on failure.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	401
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	402 @warning: It is up to the calling code to verify the timestamp, if returned, since
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	403 the requirements on the timestamp may vary between SCE-enabled protocols.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	404 """
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	405
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	406 try:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	407 envelope_serialized_string = envelope_serialized.decode("utf-8")
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	408 except UnicodeError as e:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	409 raise ValueError("Serialized envelope can't bare parsed as utf-8.") from e
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	410
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	411 custom_affixes = set(profile.custom_policies.keys())
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	412
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	413 # Make sure the envelope adheres to the schema
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	414 parser = etree.XMLParser(schema=etree.XMLSchema(etree.XML(ENVELOPE_SCHEMA.format(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	415 custom_affix_references="".join(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	416 f'<xs:element ref="{custom_affix.element_name}" minOccurs="0"/>'
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	417 for custom_affix
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	418 in custom_affixes
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	419 ),
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	420 custom_affix_definitions="".join(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	421 custom_affix.element_schema
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	422 for custom_affix
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	423 in custom_affixes
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	424 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	425 ).encode("utf-8"))))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	426
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	427 try:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	428 etree.fromstring(envelope_serialized_string, parser)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	429 except etree.XMLSyntaxError as e:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	430 raise ValueError("Serialized envelope doesn't pass schema validation.") from e
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	431
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	432 # Prepare the envelope and content elements
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	433 envelope = cast(domish.Element, ElementParser()(envelope_serialized_string))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	434 content = cast(domish.Element, next(envelope.elements(NS_SCE, "content")))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	435
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	436 # Verify the affixes
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	437 rpad_element = cast(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	438 Optional[domish.Element],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	439 next(envelope.elements(NS_SCE, "rpad"), None)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	440 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	441 time_element = cast(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	442 Optional[domish.Element],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	443 next(envelope.elements(NS_SCE, "time"), None)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	444 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	445 to_element = cast(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	446 Optional[domish.Element],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	447 next(envelope.elements(NS_SCE, "to"), None)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	448 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	449 from_element = cast(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	450 Optional[domish.Element],
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	451 next(envelope.elements(NS_SCE, "from"), None)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	452 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	453
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	454 # The rpad doesn't need verification.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	455 rpad_value = None if rpad_element is None else str(rpad_element)
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	456
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	457 # The time affix isn't verified other than that the timestamp is parseable.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	458 try:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	459 timestamp_value = None if time_element is None else \
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	460 XEP_0082.parse_datetime(time_element["stamp"])
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	461 except ValueError as e:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	462 raise AffixVerificationFailed("Malformed time affix") from e
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	463
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	464 # The to affix is verified by comparing the to attribute of the stanza with the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	465 # JID referenced by the affix. Note that only bare JIDs are compared as per the
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	466 # specification.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	467 recipient_value: Optional[jid.JID] = None
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	468 if to_element is not None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	469 recipient_value = jid.JID(to_element["jid"])
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	470
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	471 recipient_actual = cast(Optional[str], stanza.getAttribute("to", None))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	472 if recipient_actual is None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	473 raise AffixVerificationFailed(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	474 "'To' affix is included in the envelope, but the stanza is lacking a"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	475 " 'to' attribute to compare the value to."
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	476 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	477
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	478 recipient_actual_bare_jid = jid.JID(recipient_actual).userhost()
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	479 recipient_target_bare_jid = recipient_value.userhost()
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	480
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	481 if recipient_actual_bare_jid != recipient_target_bare_jid:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	482 raise AffixVerificationFailed(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	483 f"Mismatch between actual and target recipient bare JIDs:"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	484 f" {recipient_actual_bare_jid} vs {recipient_target_bare_jid}."
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	485 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	486
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	487 # The from affix is verified by comparing the from attribute of the stanza with
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	488 # the JID referenced by the affix. Note that only bare JIDs are compared as per
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	489 # the specification.
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	490 sender_value: Optional[jid.JID] = None
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	491 if from_element is not None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	492 sender_value = jid.JID(from_element["jid"])
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	493
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	494 sender_actual = cast(Optional[str], stanza.getAttribute("from", None))
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	495 if sender_actual is None:
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	496 raise AffixVerificationFailed(
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	497 "'From' affix is included in the envelope, but the stanza is lacking"
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	498 " a 'from' attribute to compare the value to."
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	499 )
00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption: Syndace <me@syndace.dev> parents: diff changeset	500

3877

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

1 #!/usr/bin/env python3

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

2

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

3 # Libervia plugin for Stanza Content Encryption

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

5

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

6 # This program is free software: you can redistribute it and/or modify

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

7 # it under the terms of the GNU Affero General Public License as published by

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

8 # the Free Software Foundation, either version 3 of the License, or

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

9 # (at your option) any later version.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

10

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

11 # This program is distributed in the hope that it will be useful,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

12 # but WITHOUT ANY WARRANTY; without even the implied warranty of

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

14 # GNU Affero General Public License for more details.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

15

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

16 # You should have received a copy of the GNU Affero General Public License

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

17 # along with this program. If not, see <http://www.gnu.org/licenses/>.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

18

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

19 # Type-check with `mypy --strict --disable-error-code no-untyped-call`

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

20 # Lint with `pylint`

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

21

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

22 from abc import ABC, abstractmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

23 from datetime import datetime

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

24 import enum

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

25 import secrets

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

26 import string

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

27 from typing import Dict, Iterator, List, NamedTuple, Optional, Set, Tuple, Union, cast

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

28

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

29 from lxml import etree

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

30

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

31 from sat.core.constants import Const as C

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

32 from sat.core.i18n import D_

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

33 from sat.core.log import Logger, getLogger

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

34 from sat.core.sat_main import SAT

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

35 from sat.tools.xml_tools import ElementParser

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

36 from sat.plugins.plugin_xep_0033 import NS_ADDRESS

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

37 from sat.plugins.plugin_xep_0082 import XEP_0082

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

38 from sat.plugins.plugin_xep_0334 import NS_HINTS

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

39 from sat.plugins.plugin_xep_0359 import NS_SID

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

40 from sat.plugins.plugin_xep_0380 import NS_EME

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

41 from twisted.words.protocols.jabber import jid

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

42 from twisted.words.xish import domish

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

43

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

44

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

45 __all__ = [ # pylint: disable=unused-variable

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

46 "PLUGIN_INFO",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

47 "NS_SCE",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

48 "XEP_0420",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

49 "ProfileRequirementsNotMet",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

50 "AffixVerificationFailed",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

51 "SCECustomAffix",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

52 "SCEAffixPolicy",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

53 "SCEProfile",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

54 "SCEAffixValues"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

55 ]

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

56

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

57

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

58 log = cast(Logger, getLogger(__name__))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

59

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

60

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

61 PLUGIN_INFO = {

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

62 C.PI_NAME: "SCE",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

63 C.PI_IMPORT_NAME: "XEP-0420",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

64 C.PI_TYPE: "SEC",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

65 C.PI_PROTOCOLS: [ "XEP-0420" ],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

66 C.PI_DEPENDENCIES: [ "XEP-0334", "XEP-0082" ],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

67 C.PI_RECOMMENDATIONS: [ "XEP-0045", "XEP-0033", "XEP-0359" ],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

68 C.PI_MAIN: "XEP_0420",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

69 C.PI_HANDLER: "no",

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

70 C.PI_DESCRIPTION: D_("Implementation of Stanza Content Encryption"),

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

71 }

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

72

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

73

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

74 NS_SCE = "urn:xmpp:sce:1"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

75

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

76

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

77 class ProfileRequirementsNotMet(Exception):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

78 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

79 Raised by :meth:`XEP_0420.unpack_stanza` in case the requirements formulated by the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

80 profile are not met.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

81 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

82

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

83

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

84 class AffixVerificationFailed(Exception):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

85 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

86 Raised by :meth:`XEP_0420.unpack_stanza` in case of affix verification failure.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

87 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

88

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

89

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

90 class SCECustomAffix(ABC):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

91 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

92 Interface for custom affixes of SCE profiles.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

93 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

94

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

95 @property

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

96 @abstractmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

97 def element_name(self) -> str:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

98 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

99 @return: The name of the affix's XML element.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

100 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

101

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

102 @property

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

103 @abstractmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

104 def element_schema(self) -> str:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

105 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

106 @return: The XML schema definition of the affix element's XML structure, i.e. the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

107 ``<xs:element/>`` schema element. This element will be referenced using

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

108 ``<xs:element ref="{element_name}"/>``.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

109 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

110

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

111 @abstractmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

112 def create(self, stanza: domish.Element) -> domish.Element:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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diff changeset

113 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

114 @param stanza: The stanza element which has been processed by

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

115 :meth:`XEP_0420.pack_stanza`, i.e. all encryptable children have been removed

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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parents:

diff changeset

116 and only the root ``<message/>`` or ``<iq/>`` and unencryptable children

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

117 remain. Do not modify.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

118 @return: An affix element to include in the envelope. The element must have the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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parents:

diff changeset

119 name :attr:`element_name` and must validate using :attr:`element_schema`.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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120 @raise ValueError: if the affix couldn't be built.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

121 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

122

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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diff changeset

123 @abstractmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

124 def verify(self, stanza: domish.Element, element: domish.Element) -> None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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125 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

126 @param stanza: The stanza element before being processed by

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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diff changeset

127 :meth:`XEP_0420.unpack_stanza`, i.e. all encryptable children have been

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

128 removed and only the root ``<message/>`` or ``<iq/>`` and unencryptable

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

129 children remain. Do not modify.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

130 @param element: The affix element to verify.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

131 @raise AffixVerificationFailed: on verification failure.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

132 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

133

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

134

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

135 @enum.unique

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136 class SCEAffixPolicy(enum.Enum):

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137 """

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138 Policy for the presence of an affix in an SCE envelope.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

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139 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

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140

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141 REQUIRED: str = "REQUIRED"

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Syndace <me@syndace.dev>

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142 OPTIONAL: str = "OPTIONAL"

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Syndace <me@syndace.dev>

parents:

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143 NOT_NEEDED: str = "NOT_NEEDED"

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144

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Syndace <me@syndace.dev>

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145

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Syndace <me@syndace.dev>

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146 class SCEProfile(NamedTuple):

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147 # pylint: disable=invalid-name

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148 """

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Syndace <me@syndace.dev>

parents:

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149 An SCE profile, i.e. the definition which affixes are required, optional or not needed

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150 at all by an SCE-enabled encryption protocol.

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151 """

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Syndace <me@syndace.dev>

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152

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153 rpad_policy: SCEAffixPolicy

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Syndace <me@syndace.dev>

parents:

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154 time_policy: SCEAffixPolicy

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Syndace <me@syndace.dev>

parents:

diff changeset

155 to_policy: SCEAffixPolicy

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Syndace <me@syndace.dev>

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diff changeset

156 from_policy: SCEAffixPolicy

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157 custom_policies: Dict[SCECustomAffix, SCEAffixPolicy]

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158

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159

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Syndace <me@syndace.dev>

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160 class SCEAffixValues(NamedTuple):

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161 # pylint: disable=invalid-name

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162 """

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parents:

diff changeset

163 Structure returned by :meth:`XEP_0420.unpack_stanza` with the parsed/processes values

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parents:

diff changeset

164 of all affixes included in the envelope. For custom affixes, the whole affix element

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165 is returned.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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166 """

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Syndace <me@syndace.dev>

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167

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168 rpad: Optional[str]

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169 timestamp: Optional[datetime]

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170 recipient: Optional[jid.JID]

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parents:

diff changeset

171 sender: Optional[jid.JID]

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172 custom: Dict[SCECustomAffix, domish.Element]

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173

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174

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175 ENVELOPE_SCHEMA = """<?xml version="1.0" encoding="utf8"?>

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176 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"

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177 targetNamespace="urn:xmpp:sce:1"

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178 xmlns="urn:xmpp:sce:1">

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179

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180 <xs:element name="envelope">

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Syndace <me@syndace.dev>

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181 <xs:complexType>

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182 <xs:all>

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183 <xs:element ref="content"/>

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Syndace <me@syndace.dev>

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184 <xs:element ref="rpad" minOccurs="0"/>

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185 <xs:element ref="time" minOccurs="0"/>

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parents:

diff changeset

186 <xs:element ref="to" minOccurs="0"/>

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187 <xs:element ref="from" minOccurs="0"/>

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188 {custom_affix_references}

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189 </xs:all>

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190 </xs:complexType>

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191 </xs:element>

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192

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Syndace <me@syndace.dev>

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193 <xs:element name="content">

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Syndace <me@syndace.dev>

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194 <xs:complexType>

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195 <xs:sequence>

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196 <xs:any minOccurs="0" maxOccurs="unbounded" processContents="skip"/>

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197 </xs:sequence>

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198 </xs:complexType>

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199 </xs:element>

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200

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diff changeset

201 <xs:element name="rpad" type="xs:string"/>

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Syndace <me@syndace.dev>

parents:

diff changeset

202

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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203 <xs:element name="time">

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Syndace <me@syndace.dev>

parents:

diff changeset

204 <xs:complexType>

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parents:

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205 <xs:attribute name="stamp" type="xs:dateTime"/>

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Syndace <me@syndace.dev>

parents:

diff changeset

206 </xs:complexType>

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Syndace <me@syndace.dev>

parents:

diff changeset

207 </xs:element>

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Syndace <me@syndace.dev>

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208

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Syndace <me@syndace.dev>

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209 <xs:element name="to">

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Syndace <me@syndace.dev>

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diff changeset

210 <xs:complexType>

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Syndace <me@syndace.dev>

parents:

diff changeset

211 <xs:attribute name="jid" type="xs:string"/>

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Syndace <me@syndace.dev>

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diff changeset

212 </xs:complexType>

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Syndace <me@syndace.dev>

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213 </xs:element>

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Syndace <me@syndace.dev>

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214

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parents:

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215 <xs:element name="from">

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Syndace <me@syndace.dev>

parents:

diff changeset

216 <xs:complexType>

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Syndace <me@syndace.dev>

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diff changeset

217 <xs:attribute name="jid" type="xs:string"/>

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Syndace <me@syndace.dev>

parents:

diff changeset

218 </xs:complexType>

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Syndace <me@syndace.dev>

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219 </xs:element>

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Syndace <me@syndace.dev>

parents:

diff changeset

220

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diff changeset

221 {custom_affix_definitions}

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Syndace <me@syndace.dev>

parents:

diff changeset

222 </xs:schema>

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Syndace <me@syndace.dev>

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223 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

224

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

225

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

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226 class XEP_0420: # pylint: disable=invalid-name

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

227 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

228 Implementation of XEP-0420: Stanza Content Encryption under namespace

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

229 ``urn:xmpp:sce:1``.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

230

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diff changeset

231 This is a passive plugin, i.e. it doesn't hook into any triggers to process stanzas

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Syndace <me@syndace.dev>

parents:

diff changeset

232 actively, but offers API for other plugins to use.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

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233 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

234

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

235 # Set of namespaces whose elements are never allowed to be transferred in an encrypted

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

236 # envelope.

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Syndace <me@syndace.dev>

parents:

diff changeset

237 MUST_BE_PLAINTEXT_NAMESPACES: Set[str] = {

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diff changeset

238 NS_HINTS,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

239 NS_SID, # TODO: Not sure whether this ban applies to both stanza-id and origin-id

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Syndace <me@syndace.dev>

parents:

diff changeset

240 NS_ADDRESS,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

241 # Not part of the specification (yet), but just doesn't make sense in an encrypted

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

242 # envelope:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

243 NS_EME

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

244 }

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

245

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diff changeset

246 # Set of (namespace, element name) tuples that define elements which are never allowed

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Syndace <me@syndace.dev>

parents:

diff changeset

247 # to be transferred in an encrypted envelope. If all elements under a certain

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

248 # namespace are forbidden, the namespace can be added to

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parents:

diff changeset

249 # :attr:`MUST_BE_PLAINTEXT_NAMESPACES` instead.

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diff changeset

250 # Note: only full namespaces are forbidden by the spec for now, the following is for

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parents:

diff changeset

251 # potential future use.

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diff changeset

252 MUST_BE_PLAINTEXT_ELEMENTS: Set[Tuple[str, str]] = set()

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253

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254 def __init__(self, sat: SAT) -> None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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255 """

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parents:

diff changeset

256 @param sat: The SAT instance.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

257 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

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258

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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diff changeset

259 @staticmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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260 def pack_stanza(profile: SCEProfile, stanza: domish.Element) -> bytes:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

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261 """Pack a stanza according to Stanza Content Encryption.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

262

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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parents:

diff changeset

263 Removes all elements from the stanza except for a few exceptions that explicitly

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

264 need to be transferred in plaintext, e.g. because they contain hints/instructions

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Syndace <me@syndace.dev>

parents:

diff changeset

265 for the server on how to process the stanza. Together with the affix elements as

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parents:

diff changeset

266 requested by the profile, the removed elements are added to an envelope XML

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

267 structure that builds the plaintext to be encrypted by the SCE-enabled encryption

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

268 scheme. Optional affixes are always added to the structure, i.e. they are treated

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

269 by the packing code as if they were required.

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Syndace <me@syndace.dev>

parents:

diff changeset

270

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Syndace <me@syndace.dev>

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diff changeset

271 Once built, the envelope structure is serialized to a byte string and returned for

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

272 the encryption scheme to encrypt and add to the stanza.

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Syndace <me@syndace.dev>

parents:

diff changeset

273

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274 @param profile: The SCE profile, i.e. the definition of affixes to include in the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

275 envelope.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

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diff changeset

276 @param stanza: The stanza to process. Will be modified by the call.

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diff changeset

277 @return: The serialized envelope structure that builds the plaintext for the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

278 encryption scheme to process.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

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diff changeset

279 @raise ValueError: if the <to/> or <from/> affixes are requested but the stanza

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

280 doesn't have the "to"/"from" attribute set to extract the value from. Can also

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

281 be raised by custom affixes.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

282

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

283 @warning: It is up to the calling code to add a <store/> message processing hint

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

284 if applicable.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

285 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

286

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

287 # Prepare the envelope and content elements

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

288 envelope = domish.Element((NS_SCE, "envelope"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

289 content = envelope.addElement((NS_SCE, "content"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

290

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

291 # Note the serialized byte size of the content element before adding any children

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

292 empty_content_byte_size = len(content.toXml().encode("utf-8"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

293

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

294 # Just for type safety

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

295 stanza_children = cast(List[Union[domish.Element, str]], stanza.children)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

296 content_children = cast(List[Union[domish.Element, str]], content.children)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

297

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

298 # Move elements that are not explicitly forbidden from being encrypted from the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

299 # stanza to the content element.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

300 for child in list(cast(Iterator[domish.Element], stanza.elements())):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

301 if (

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

302 child.uri not in XEP_0420.MUST_BE_PLAINTEXT_NAMESPACES

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

303 and (child.uri, child.name) not in XEP_0420.MUST_BE_PLAINTEXT_ELEMENTS

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

304 ):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

305 # Remove the child from the stanza

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

306 stanza_children.remove(child)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

307

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

308 # A namespace of ``None`` can be used on domish elements to inherit the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

309 # namespace from the parent. When moving elements from the stanza root to

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

310 # the content element, however, we don't want elements to inherit the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

311 # namespace of the content element. Thus, check for elements with ``None``

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

312 # for their namespace and set the namespace to jabber:client, which is the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

313 # namespace of the parent element.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

314 if child.uri is None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

315 child.uri = C.NS_CLIENT

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

316 child.defaultUri = C.NS_CLIENT

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

317

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

318 # Add the child with corrected namespaces to the content element

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

319 content_children.append(child)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

320

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

321 # Add the affixes requested by the profile

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

322 if profile.rpad_policy is not SCEAffixPolicy.NOT_NEEDED:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

323 # The specification defines the rpad affix to contain "[...] a randomly

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

324 # generated sequence of random length between 0 and 200 characters." This

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

325 # implementation differs a bit from the specification in that a minimum size

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

326 # other than 0 is chosen depending on the serialized size of the content

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

327 # element. This is to prevent the scenario where the encrypted content is

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

328 # short and the rpad is also randomly chosen to be short, which could allow

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

329 # guessing the content of a short message. To do so, the rpad length is first

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

330 # chosen to pad the content to at least 53 bytes, then afterwards another 0 to

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

331 # 200 bytes are added. Note that single-byte characters are used by this

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

332 # implementation, thus the number of characters equals the number of bytes.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

333 content_byte_size = len(content.toXml().encode("utf-8"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

334 content_byte_size_diff = content_byte_size - empty_content_byte_size

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

335 rpad_length = max(0, 53 - content_byte_size_diff) + secrets.randbelow(201)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

336 rpad_content = "".join(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

337 secrets.choice(string.digits + string.ascii_letters + string.punctuation)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

338 for __

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

339 in range(rpad_length)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

340 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

341 envelope.addElement((NS_SCE, "rpad"), content=rpad_content)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

342

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

343 if profile.time_policy is not SCEAffixPolicy.NOT_NEEDED:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

344 time_element = envelope.addElement((NS_SCE, "time"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

345 time_element["stamp"] = XEP_0082.format_datetime()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

346

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

347 if profile.to_policy is not SCEAffixPolicy.NOT_NEEDED:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

348 recipient = cast(Optional[str], stanza.getAttribute("to", None))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

349 if recipient is None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

350 raise ValueError(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

351 "<to/> affix requested, but stanza doesn't have the 'to' attribute"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

352 " set."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

353 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

354

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

355 to_element = envelope.addElement((NS_SCE, "to"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

356 to_element["jid"] = jid.JID(recipient).userhost()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

357

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

358 if profile.from_policy is not SCEAffixPolicy.NOT_NEEDED:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

359 sender = cast(Optional[str], stanza.getAttribute("from", None))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

360 if sender is None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

361 raise ValueError(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

362 "<from/> affix requested, but stanza doesn't have the 'from'"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

363 " attribute set."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

364 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

365

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

366 from_element = envelope.addElement((NS_SCE, "from"))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

367 from_element["jid"] = jid.JID(sender).userhost()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

368

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

369 for affix, policy in profile.custom_policies.items():

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

370 if policy is not SCEAffixPolicy.NOT_NEEDED:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

371 envelope.addChild(affix.create(stanza))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

372

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

373 return cast(str, envelope.toXml()).encode("utf-8")

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

374

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

375 @staticmethod

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

376 def unpack_stanza(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

377 profile: SCEProfile,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

378 stanza: domish.Element,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

379 envelope_serialized: bytes

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

380 ) -> SCEAffixValues:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

381 """Unpack a stanza packed according to Stanza Content Encryption.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

382

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

383 Parses the serialized envelope as XML, verifies included affixes and makes sure

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

384 the requirements of the profile are met, and restores the stanza by moving

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

385 decrypted elements from the envelope back to the stanza top level.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

386

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

387 @param profile: The SCE profile, i.e. the definition of affixes that have to/may

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

388 be included in the envelope.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

389 @param stanza: The stanza to process. Will be modified by the call.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

390 @param envelope_serialized: The serialized envelope, i.e. the plaintext produced

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

391 by the decryption scheme utilizing SCE.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

392 @return: The parsed and processed values of all affixes that were present on the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

393 envelope, notably including the timestamp.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

394 @raise ValueError: if the serialized envelope element is malformed.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

395 @raise ProfileRequirementsNotMet: if one or more affixes required by the profile

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

396 are missing from the envelope.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

397 @raise AffixVerificationFailed: if an affix included in the envelope fails to

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

398 validate. It doesn't matter whether the affix is required by the profile or

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

399 not, all affixes included in the envelope are validated and cause this

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

400 exception to be raised on failure.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

401

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

402 @warning: It is up to the calling code to verify the timestamp, if returned, since

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

403 the requirements on the timestamp may vary between SCE-enabled protocols.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

404 """

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

405

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

406 try:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

407 envelope_serialized_string = envelope_serialized.decode("utf-8")

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

408 except UnicodeError as e:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

409 raise ValueError("Serialized envelope can't bare parsed as utf-8.") from e

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

410

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

411 custom_affixes = set(profile.custom_policies.keys())

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

412

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

413 # Make sure the envelope adheres to the schema

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

414 parser = etree.XMLParser(schema=etree.XMLSchema(etree.XML(ENVELOPE_SCHEMA.format(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

415 custom_affix_references="".join(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

416 f'<xs:element ref="{custom_affix.element_name}" minOccurs="0"/>'

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

417 for custom_affix

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

418 in custom_affixes

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

419 ),

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

420 custom_affix_definitions="".join(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

421 custom_affix.element_schema

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

422 for custom_affix

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

423 in custom_affixes

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

424 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

425 ).encode("utf-8"))))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

426

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

427 try:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

428 etree.fromstring(envelope_serialized_string, parser)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

429 except etree.XMLSyntaxError as e:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

430 raise ValueError("Serialized envelope doesn't pass schema validation.") from e

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

431

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

432 # Prepare the envelope and content elements

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

433 envelope = cast(domish.Element, ElementParser()(envelope_serialized_string))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

434 content = cast(domish.Element, next(envelope.elements(NS_SCE, "content")))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

435

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

436 # Verify the affixes

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

437 rpad_element = cast(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

438 Optional[domish.Element],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

439 next(envelope.elements(NS_SCE, "rpad"), None)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

440 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

441 time_element = cast(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

442 Optional[domish.Element],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

443 next(envelope.elements(NS_SCE, "time"), None)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

444 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

445 to_element = cast(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

446 Optional[domish.Element],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

447 next(envelope.elements(NS_SCE, "to"), None)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

448 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

449 from_element = cast(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

450 Optional[domish.Element],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

451 next(envelope.elements(NS_SCE, "from"), None)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

452 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

453

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

454 # The rpad doesn't need verification.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

455 rpad_value = None if rpad_element is None else str(rpad_element)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

456

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

457 # The time affix isn't verified other than that the timestamp is parseable.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

458 try:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

459 timestamp_value = None if time_element is None else \

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

460 XEP_0082.parse_datetime(time_element["stamp"])

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

461 except ValueError as e:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

462 raise AffixVerificationFailed("Malformed time affix") from e

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

463

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

464 # The to affix is verified by comparing the to attribute of the stanza with the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

465 # JID referenced by the affix. Note that only bare JIDs are compared as per the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

466 # specification.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

467 recipient_value: Optional[jid.JID] = None

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

468 if to_element is not None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

469 recipient_value = jid.JID(to_element["jid"])

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

470

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

471 recipient_actual = cast(Optional[str], stanza.getAttribute("to", None))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

472 if recipient_actual is None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

473 raise AffixVerificationFailed(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

474 "'To' affix is included in the envelope, but the stanza is lacking a"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

475 " 'to' attribute to compare the value to."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

476 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

477

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

478 recipient_actual_bare_jid = jid.JID(recipient_actual).userhost()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

479 recipient_target_bare_jid = recipient_value.userhost()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

480

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

481 if recipient_actual_bare_jid != recipient_target_bare_jid:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

482 raise AffixVerificationFailed(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

483 f"Mismatch between actual and target recipient bare JIDs:"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

484 f" {recipient_actual_bare_jid} vs {recipient_target_bare_jid}."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

485 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

486

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

487 # The from affix is verified by comparing the from attribute of the stanza with

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

488 # the JID referenced by the affix. Note that only bare JIDs are compared as per

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

489 # the specification.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

490 sender_value: Optional[jid.JID] = None

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

491 if from_element is not None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

492 sender_value = jid.JID(from_element["jid"])

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

493

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

494 sender_actual = cast(Optional[str], stanza.getAttribute("from", None))

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

495 if sender_actual is None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

496 raise AffixVerificationFailed(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

497 "'From' affix is included in the envelope, but the stanza is lacking"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

498 " a 'from' attribute to compare the value to."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

499 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

500

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

501 sender_actual_bare_jid = jid.JID(sender_actual).userhost()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

502 sender_target_bare_jid = sender_value.userhost()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

503

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

504 if sender_actual_bare_jid != sender_target_bare_jid:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

505 raise AffixVerificationFailed(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

506 f"Mismatch between actual and target sender bare JIDs:"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

507 f" {sender_actual_bare_jid} vs {sender_target_bare_jid}."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

508 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

509

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

510 # Find and verify custom affixes

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

511 custom_values: Dict[SCECustomAffix, domish.Element] = {}

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

512 for affix in custom_affixes:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

513 element_name = affix.element_name

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

514 element = cast(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

515 Optional[domish.Element],

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

516 next(envelope.elements(NS_SCE, element_name), None)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

517 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

518 if element is not None:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

519 affix.verify(stanza, element)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

520 custom_values[affix] = element

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

521

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

522 # Check whether all affixes required by the profile are present

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

523 rpad_missing = \

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

524 profile.rpad_policy is SCEAffixPolicy.REQUIRED and rpad_element is None

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

525 time_missing = \

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

526 profile.time_policy is SCEAffixPolicy.REQUIRED and time_element is None

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

527 to_missing = \

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

528 profile.to_policy is SCEAffixPolicy.REQUIRED and to_element is None

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

529 from_missing = \

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

530 profile.from_policy is SCEAffixPolicy.REQUIRED and from_element is None

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

531 custom_missing = any(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

532 affix not in custom_values

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

533 for affix, policy

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

534 in profile.custom_policies.items()

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

535 if policy is SCEAffixPolicy.REQUIRED

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

536 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

537

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

538 if rpad_missing or time_missing or to_missing or from_missing or custom_missing:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

539 custom_missing_string = ""

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

540 for custom_affix in custom_affixes:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

541 value = "present" if custom_affix in custom_values else "missing"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

542 custom_missing_string += f", [custom]{custom_affix.element_name}={value}"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

543

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

544 raise ProfileRequirementsNotMet(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

545 f"SCE envelope is missing affixes required by the profile {profile}."

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

546 f" Affix presence:"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

547 f" rpad={'missing' if rpad_missing else 'present'}"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

548 f", time={'missing' if time_missing else 'present'}"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

549 f", to={'missing' if to_missing else 'present'}"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

550 f", from={'missing' if from_missing else 'present'}"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

551 + custom_missing_string

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

552 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

553

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

554 # Just for type safety

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

555 content_children = cast(List[Union[domish.Element, str]], content.children)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

556 stanza_children = cast(List[Union[domish.Element, str]], stanza.children)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

557

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

558 # Move elements that are not explicitly forbidden from being encrypted from the

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

559 # content element to the stanza.

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

560 for child in list(cast(Iterator[domish.Element], content.elements())):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

561 if (

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

562 child.uri in XEP_0420.MUST_BE_PLAINTEXT_NAMESPACES

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

563 or (child.uri, child.name) in XEP_0420.MUST_BE_PLAINTEXT_ELEMENTS

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

564 ):

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

565 log.warning(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

566 f"An element that MUST be transferred in plaintext was found in an"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

567 f" SCE envelope: {child.toXml()}"

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

568 )

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

569 else:

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

570 # Remove the child from the content element

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

571 content_children.remove(child)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

572

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

573 # Add the child to the stanza

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

574 stanza_children.append(child)

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

575

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

576 return SCEAffixValues(

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

577 rpad_value,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

578 timestamp_value,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

579 recipient_value,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

580 sender_value,

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

581 custom_values

00212260f659 plugin XEP-0420: Implementation of Stanza Content Encryption:

Syndace <me@syndace.dev>

parents:

diff changeset

582 )

Mercurial > libervia-backend

annotate sat/plugins/plugin_xep_0420.py @ 3877:00212260f659