# -*- coding: utf-8 -*- # 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 import attr import jinja2 import pkg_resources 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_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) 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" ) # 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) # 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) # 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") ) template_dir = saml2_config.get("template_dir") if not template_dir: template_dir = pkg_resources.resource_filename("synapse", "res/templates",) loader = jinja2.FileSystemLoader(template_dir) # enable auto-escape here, to having to remember to escape manually in the # template env = jinja2.Environment(loader=loader, autoescape=True) self.saml2_error_html_template = env.get_template("saml_error.html") 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 + "_matrix/saml2/metadata.xml" response_url = public_baseurl + "_matrix/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 ## # 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. # # (You will probably also want to set the following options to `false` to # disable the regular login/registration flows: # * enable_registration # * password_config.enabled # # Once SAML support is enabled, a metadata file will be exposed at # https://<server>:<port>/_matrix/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>/_matrix/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 can use either a local file or # # (preferably) a URL. # metadata: # #local: ["saml2/idp.xml"] # remote: # - url: https://our_idp/metadata.xml # # # 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"] # # 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" # Directory in which Synapse will try to find the template files below. # If not set, default templates from within the Synapse package will be used. # # DO NOT UNCOMMENT THIS SETTING unless you want to customise the templates. # If you *do* uncomment it, you will need to make sure that all the templates # below are in the directory. # # Synapse will look for the following templates in this directory: # # * HTML page to display to users if something goes wrong during the # authentication process: 'saml_error.html'. # # When rendering, this template is given the following variables: # * code: an HTML error code corresponding to the error that is being # returned (typically 400 or 500) # # * msg: a textual message describing the error. # # The variables will automatically be HTML-escaped. # # You can see the default templates at: # https://github.com/matrix-org/synapse/tree/master/synapse/res/templates # #template_dir: "res/templates" """ % { "config_dir_path": config_dir_path } @attr.s(frozen=True) class SamlAttributeRequirement: """Object describing a single requirement for SAML attributes.""" attribute = attr.ib(type=str) value = attr.ib(type=str) JSON_SCHEMA = { "type": "object", "properties": {"attribute": {"type": "string"}, "value": {"type": "string"}}, "required": ["attribute", "value"], } ATTRIBUTE_REQUIREMENTS_SCHEMA = { "type": "array", "items": SamlAttributeRequirement.JSON_SCHEMA, } def _parse_attribute_requirements_def( attribute_requirements: Any, ) -> List[SamlAttributeRequirement]: validate_config( ATTRIBUTE_REQUIREMENTS_SCHEMA, attribute_requirements, config_path=["saml2_config", "attribute_requirements"], ) return [SamlAttributeRequirement(**x) for x in attribute_requirements]