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Diffstat (limited to 'synapse/config/saml2.py')
-rw-r--r-- | synapse/config/saml2.py | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/synapse/config/saml2.py b/synapse/config/saml2.py new file mode 100644 index 0000000000..3d1218c8d1 --- /dev/null +++ b/synapse/config/saml2.py @@ -0,0 +1,420 @@ +# Copyright 2018 New Vector Ltd +# Copyright 2019 The Matrix.org Foundation C.I.C. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +import logging +from typing import Any, List + +from synapse.config.sso import SsoAttributeRequirement +from synapse.python_dependencies import DependencyException, check_requirements +from synapse.util.module_loader import load_module, load_python_module + +from ._base import Config, ConfigError +from ._util import validate_config + +logger = logging.getLogger(__name__) + +DEFAULT_USER_MAPPING_PROVIDER = "synapse.handlers.saml.DefaultSamlMappingProvider" +# The module that DefaultSamlMappingProvider is in was renamed, we want to +# transparently handle both the same. +LEGACY_USER_MAPPING_PROVIDER = ( + "synapse.handlers.saml_handler.DefaultSamlMappingProvider" +) + + +def _dict_merge(merge_dict, into_dict): + """Do a deep merge of two dicts + + Recursively merges `merge_dict` into `into_dict`: + * For keys where both `merge_dict` and `into_dict` have a dict value, the values + are recursively merged + * For all other keys, the values in `into_dict` (if any) are overwritten with + the value from `merge_dict`. + + Args: + merge_dict (dict): dict to merge + into_dict (dict): target dict + """ + for k, v in merge_dict.items(): + if k not in into_dict: + into_dict[k] = v + continue + + current_val = into_dict[k] + + if isinstance(v, dict) and isinstance(current_val, dict): + _dict_merge(v, current_val) + continue + + # otherwise we just overwrite + into_dict[k] = v + + +class SAML2Config(Config): + section = "saml2" + + def read_config(self, config, **kwargs): + self.saml2_enabled = False + + saml2_config = config.get("saml2_config") + + if not saml2_config or not saml2_config.get("enabled", True): + return + + if not saml2_config.get("sp_config") and not saml2_config.get("config_path"): + return + + try: + check_requirements("saml2") + except DependencyException as e: + raise ConfigError( + e.message # noqa: B306, DependencyException.message is a property + ) + + self.saml2_enabled = True + + attribute_requirements = saml2_config.get("attribute_requirements") or [] + self.attribute_requirements = _parse_attribute_requirements_def( + attribute_requirements + ) + + self.saml2_grandfathered_mxid_source_attribute = saml2_config.get( + "grandfathered_mxid_source_attribute", "uid" + ) + + self.saml2_idp_entityid = saml2_config.get("idp_entityid", None) + + # user_mapping_provider may be None if the key is present but has no value + ump_dict = saml2_config.get("user_mapping_provider") or {} + + # Use the default user mapping provider if not set + ump_dict.setdefault("module", DEFAULT_USER_MAPPING_PROVIDER) + if ump_dict.get("module") == LEGACY_USER_MAPPING_PROVIDER: + ump_dict["module"] = DEFAULT_USER_MAPPING_PROVIDER + + # Ensure a config is present + ump_dict["config"] = ump_dict.get("config") or {} + + if ump_dict["module"] == DEFAULT_USER_MAPPING_PROVIDER: + # Load deprecated options for use by the default module + old_mxid_source_attribute = saml2_config.get("mxid_source_attribute") + if old_mxid_source_attribute: + logger.warning( + "The config option saml2_config.mxid_source_attribute is deprecated. " + "Please use saml2_config.user_mapping_provider.config" + ".mxid_source_attribute instead." + ) + ump_dict["config"]["mxid_source_attribute"] = old_mxid_source_attribute + + old_mxid_mapping = saml2_config.get("mxid_mapping") + if old_mxid_mapping: + logger.warning( + "The config option saml2_config.mxid_mapping is deprecated. Please " + "use saml2_config.user_mapping_provider.config.mxid_mapping instead." + ) + ump_dict["config"]["mxid_mapping"] = old_mxid_mapping + + # Retrieve an instance of the module's class + # Pass the config dictionary to the module for processing + ( + self.saml2_user_mapping_provider_class, + self.saml2_user_mapping_provider_config, + ) = load_module(ump_dict, ("saml2_config", "user_mapping_provider")) + + # Ensure loaded user mapping module has defined all necessary methods + # Note parse_config() is already checked during the call to load_module + required_methods = [ + "get_saml_attributes", + "saml_response_to_user_attributes", + "get_remote_user_id", + ] + missing_methods = [ + method + for method in required_methods + if not hasattr(self.saml2_user_mapping_provider_class, method) + ] + if missing_methods: + raise ConfigError( + "Class specified by saml2_config." + "user_mapping_provider.module is missing required " + "methods: %s" % (", ".join(missing_methods),) + ) + + # Get the desired saml auth response attributes from the module + saml2_config_dict = self._default_saml_config_dict( + *self.saml2_user_mapping_provider_class.get_saml_attributes( + self.saml2_user_mapping_provider_config + ) + ) + _dict_merge( + merge_dict=saml2_config.get("sp_config", {}), into_dict=saml2_config_dict + ) + + config_path = saml2_config.get("config_path", None) + if config_path is not None: + mod = load_python_module(config_path) + _dict_merge(merge_dict=mod.CONFIG, into_dict=saml2_config_dict) + + import saml2.config + + self.saml2_sp_config = saml2.config.SPConfig() + self.saml2_sp_config.load(saml2_config_dict) + + # session lifetime: in milliseconds + self.saml2_session_lifetime = self.parse_duration( + saml2_config.get("saml_session_lifetime", "15m") + ) + + def _default_saml_config_dict( + self, required_attributes: set, optional_attributes: set + ): + """Generate a configuration dictionary with required and optional attributes that + will be needed to process new user registration + + Args: + required_attributes: SAML auth response attributes that are + necessary to function + optional_attributes: SAML auth response attributes that can be used to add + additional information to Synapse user accounts, but are not required + + Returns: + dict: A SAML configuration dictionary + """ + import saml2 + + public_baseurl = self.public_baseurl + if public_baseurl is None: + raise ConfigError("saml2_config requires a public_baseurl to be set") + + if self.saml2_grandfathered_mxid_source_attribute: + optional_attributes.add(self.saml2_grandfathered_mxid_source_attribute) + optional_attributes -= required_attributes + + metadata_url = public_baseurl + "_synapse/client/saml2/metadata.xml" + response_url = public_baseurl + "_synapse/client/saml2/authn_response" + return { + "entityid": metadata_url, + "service": { + "sp": { + "endpoints": { + "assertion_consumer_service": [ + (response_url, saml2.BINDING_HTTP_POST) + ] + }, + "required_attributes": list(required_attributes), + "optional_attributes": list(optional_attributes), + # "name_id_format": saml2.saml.NAMEID_FORMAT_PERSISTENT, + } + }, + } + + def generate_config_section(self, config_dir_path, server_name, **kwargs): + return """\ + ## Single sign-on integration ## + + # The following settings can be used to make Synapse use a single sign-on + # provider for authentication, instead of its internal password database. + # + # You will probably also want to set the following options to `false` to + # disable the regular login/registration flows: + # * enable_registration + # * password_config.enabled + # + # You will also want to investigate the settings under the "sso" configuration + # section below. + + # Enable SAML2 for registration and login. Uses pysaml2. + # + # At least one of `sp_config` or `config_path` must be set in this section to + # enable SAML login. + # + # Once SAML support is enabled, a metadata file will be exposed at + # https://<server>:<port>/_synapse/client/saml2/metadata.xml, which you may be able to + # use to configure your SAML IdP with. Alternatively, you can manually configure + # the IdP to use an ACS location of + # https://<server>:<port>/_synapse/client/saml2/authn_response. + # + saml2_config: + # `sp_config` is the configuration for the pysaml2 Service Provider. + # See pysaml2 docs for format of config. + # + # Default values will be used for the 'entityid' and 'service' settings, + # so it is not normally necessary to specify them unless you need to + # override them. + # + sp_config: + # Point this to the IdP's metadata. You must provide either a local + # file via the `local` attribute or (preferably) a URL via the + # `remote` attribute. + # + #metadata: + # local: ["saml2/idp.xml"] + # remote: + # - url: https://our_idp/metadata.xml + + # Allowed clock difference in seconds between the homeserver and IdP. + # + # Uncomment the below to increase the accepted time difference from 0 to 3 seconds. + # + #accepted_time_diff: 3 + + # By default, the user has to go to our login page first. If you'd like + # to allow IdP-initiated login, set 'allow_unsolicited: true' in a + # 'service.sp' section: + # + #service: + # sp: + # allow_unsolicited: true + + # The examples below are just used to generate our metadata xml, and you + # may well not need them, depending on your setup. Alternatively you + # may need a whole lot more detail - see the pysaml2 docs! + + #description: ["My awesome SP", "en"] + #name: ["Test SP", "en"] + + #ui_info: + # display_name: + # - lang: en + # text: "Display Name is the descriptive name of your service." + # description: + # - lang: en + # text: "Description should be a short paragraph explaining the purpose of the service." + # information_url: + # - lang: en + # text: "https://example.com/terms-of-service" + # privacy_statement_url: + # - lang: en + # text: "https://example.com/privacy-policy" + # keywords: + # - lang: en + # text: ["Matrix", "Element"] + # logo: + # - lang: en + # text: "https://example.com/logo.svg" + # width: "200" + # height: "80" + + #organization: + # name: Example com + # display_name: + # - ["Example co", "en"] + # url: "http://example.com" + + #contact_person: + # - given_name: Bob + # sur_name: "the Sysadmin" + # email_address": ["admin@example.com"] + # contact_type": technical + + # Instead of putting the config inline as above, you can specify a + # separate pysaml2 configuration file: + # + #config_path: "%(config_dir_path)s/sp_conf.py" + + # The lifetime of a SAML session. This defines how long a user has to + # complete the authentication process, if allow_unsolicited is unset. + # The default is 15 minutes. + # + #saml_session_lifetime: 5m + + # An external module can be provided here as a custom solution to + # mapping attributes returned from a saml provider onto a matrix user. + # + user_mapping_provider: + # The custom module's class. Uncomment to use a custom module. + # + #module: mapping_provider.SamlMappingProvider + + # Custom configuration values for the module. Below options are + # intended for the built-in provider, they should be changed if + # using a custom module. This section will be passed as a Python + # dictionary to the module's `parse_config` method. + # + config: + # The SAML attribute (after mapping via the attribute maps) to use + # to derive the Matrix ID from. 'uid' by default. + # + # Note: This used to be configured by the + # saml2_config.mxid_source_attribute option. If that is still + # defined, its value will be used instead. + # + #mxid_source_attribute: displayName + + # The mapping system to use for mapping the saml attribute onto a + # matrix ID. + # + # Options include: + # * 'hexencode' (which maps unpermitted characters to '=xx') + # * 'dotreplace' (which replaces unpermitted characters with + # '.'). + # The default is 'hexencode'. + # + # Note: This used to be configured by the + # saml2_config.mxid_mapping option. If that is still defined, its + # value will be used instead. + # + #mxid_mapping: dotreplace + + # In previous versions of synapse, the mapping from SAML attribute to + # MXID was always calculated dynamically rather than stored in a + # table. For backwards- compatibility, we will look for user_ids + # matching such a pattern before creating a new account. + # + # This setting controls the SAML attribute which will be used for this + # backwards-compatibility lookup. Typically it should be 'uid', but if + # the attribute maps are changed, it may be necessary to change it. + # + # The default is 'uid'. + # + #grandfathered_mxid_source_attribute: upn + + # It is possible to configure Synapse to only allow logins if SAML attributes + # match particular values. The requirements can be listed under + # `attribute_requirements` as shown below. All of the listed attributes must + # match for the login to be permitted. + # + #attribute_requirements: + # - attribute: userGroup + # value: "staff" + # - attribute: department + # value: "sales" + + # If the metadata XML contains multiple IdP entities then the `idp_entityid` + # option must be set to the entity to redirect users to. + # + # Most deployments only have a single IdP entity and so should omit this + # option. + # + #idp_entityid: 'https://our_idp/entityid' + """ % { + "config_dir_path": config_dir_path + } + + +ATTRIBUTE_REQUIREMENTS_SCHEMA = { + "type": "array", + "items": SsoAttributeRequirement.JSON_SCHEMA, +} + + +def _parse_attribute_requirements_def( + attribute_requirements: Any, +) -> List[SsoAttributeRequirement]: + validate_config( + ATTRIBUTE_REQUIREMENTS_SCHEMA, + attribute_requirements, + config_path=("saml2_config", "attribute_requirements"), + ) + return [SsoAttributeRequirement(**x) for x in attribute_requirements] |