diff options
Diffstat (limited to 'synapse')
| -rw-r--r-- | synapse/config/_util.py | 49 | ||||
| -rw-r--r-- | synapse/config/saml2_config.py | 50 | ||||
| -rw-r--r-- | synapse/handlers/saml_handler.py | 42 | ||||
| -rw-r--r-- | synapse/res/templates/saml_error.html | 17 |
4 files changed, 147 insertions, 11 deletions
diff --git a/synapse/config/_util.py b/synapse/config/_util.py new file mode 100644 index 0000000000..cd31b1c3c9 --- /dev/null +++ b/synapse/config/_util.py @@ -0,0 +1,49 @@ +# -*- coding: utf-8 -*- +# Copyright 2020 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. +from typing import Any, List + +import jsonschema + +from synapse.config._base import ConfigError +from synapse.types import JsonDict + + +def validate_config(json_schema: JsonDict, config: Any, config_path: List[str]) -> None: + """Validates a config setting against a JsonSchema definition + + This can be used to validate a section of the config file against a schema + definition. If the validation fails, a ConfigError is raised with a textual + description of the problem. + + Args: + json_schema: the schema to validate against + config: the configuration value to be validated + config_path: the path within the config file. This will be used as a basis + for the error message. + """ + try: + jsonschema.validate(config, json_schema) + except jsonschema.ValidationError as e: + # copy `config_path` before modifying it. + path = list(config_path) + for p in list(e.path): + if isinstance(p, int): + path.append("<item %i>" % p) + else: + path.append(str(p)) + + raise ConfigError( + "Unable to parse configuration: %s at %s" % (e.message, ".".join(path)) + ) diff --git a/synapse/config/saml2_config.py b/synapse/config/saml2_config.py index 293643b2de..9277b5f342 100644 --- a/synapse/config/saml2_config.py +++ b/synapse/config/saml2_config.py @@ -15,7 +15,9 @@ # limitations under the License. import logging +from typing import Any, List +import attr import jinja2 import pkg_resources @@ -23,6 +25,7 @@ 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__) @@ -80,6 +83,11 @@ class SAML2Config(Config): 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" ) @@ -341,6 +349,17 @@ class SAML2Config(Config): # #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. # @@ -368,3 +387,34 @@ class SAML2Config(Config): """ % { "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] diff --git a/synapse/handlers/saml_handler.py b/synapse/handlers/saml_handler.py index 2d506dc1f2..c1fcb98454 100644 --- a/synapse/handlers/saml_handler.py +++ b/synapse/handlers/saml_handler.py @@ -14,15 +14,16 @@ # limitations under the License. import logging import re -from typing import Callable, Dict, Optional, Set, Tuple +from typing import TYPE_CHECKING, Callable, Dict, Optional, Set, Tuple import attr import saml2 import saml2.response from saml2.client import Saml2Client -from synapse.api.errors import SynapseError +from synapse.api.errors import AuthError, SynapseError from synapse.config import ConfigError +from synapse.config.saml2_config import SamlAttributeRequirement from synapse.http.servlet import parse_string from synapse.http.site import SynapseRequest from synapse.module_api import ModuleApi @@ -34,6 +35,9 @@ from synapse.types import ( from synapse.util.async_helpers import Linearizer from synapse.util.iterutils import chunk_seq +if TYPE_CHECKING: + import synapse.server + logger = logging.getLogger(__name__) @@ -49,7 +53,7 @@ class Saml2SessionData: class SamlHandler: - def __init__(self, hs): + def __init__(self, hs: "synapse.server.HomeServer"): self._saml_client = Saml2Client(hs.config.saml2_sp_config) self._auth = hs.get_auth() self._auth_handler = hs.get_auth_handler() @@ -62,6 +66,7 @@ class SamlHandler: self._grandfathered_mxid_source_attribute = ( hs.config.saml2_grandfathered_mxid_source_attribute ) + self._saml2_attribute_requirements = hs.config.saml2.attribute_requirements # plugin to do custom mapping from saml response to mxid self._user_mapping_provider = hs.config.saml2_user_mapping_provider_class( @@ -73,7 +78,7 @@ class SamlHandler: self._auth_provider_id = "saml" # a map from saml session id to Saml2SessionData object - self._outstanding_requests_dict = {} + self._outstanding_requests_dict = {} # type: Dict[str, Saml2SessionData] # a lock on the mappings self._mapping_lock = Linearizer(name="saml_mapping", clock=self._clock) @@ -165,11 +170,18 @@ class SamlHandler: saml2.BINDING_HTTP_POST, outstanding=self._outstanding_requests_dict, ) + except saml2.response.UnsolicitedResponse as e: + # the pysaml2 library helpfully logs an ERROR here, but neglects to log + # the session ID. I don't really want to put the full text of the exception + # in the (user-visible) exception message, so let's log the exception here + # so we can track down the session IDs later. + logger.warning(str(e)) + raise SynapseError(400, "Unexpected SAML2 login.") except Exception as e: - raise SynapseError(400, "Unable to parse SAML2 response: %s" % (e,)) + raise SynapseError(400, "Unable to parse SAML2 response: %s." % (e,)) if saml2_auth.not_signed: - raise SynapseError(400, "SAML2 response was not signed") + raise SynapseError(400, "SAML2 response was not signed.") logger.debug("SAML2 response: %s", saml2_auth.origxml) for assertion in saml2_auth.assertions: @@ -188,6 +200,9 @@ class SamlHandler: saml2_auth.in_response_to, None ) + for requirement in self._saml2_attribute_requirements: + _check_attribute_requirement(saml2_auth.ava, requirement) + remote_user_id = self._user_mapping_provider.get_remote_user_id( saml2_auth, client_redirect_url ) @@ -294,6 +309,21 @@ class SamlHandler: del self._outstanding_requests_dict[reqid] +def _check_attribute_requirement(ava: dict, req: SamlAttributeRequirement): + values = ava.get(req.attribute, []) + for v in values: + if v == req.value: + return + + logger.info( + "SAML2 attribute %s did not match required value '%s' (was '%s')", + req.attribute, + req.value, + values, + ) + raise AuthError(403, "You are not authorized to log in here.") + + DOT_REPLACE_PATTERN = re.compile( ("[^%s]" % (re.escape("".join(mxid_localpart_allowed_characters)),)) ) diff --git a/synapse/res/templates/saml_error.html b/synapse/res/templates/saml_error.html index bfd6449c5d..01cd9bdaf3 100644 --- a/synapse/res/templates/saml_error.html +++ b/synapse/res/templates/saml_error.html @@ -2,10 +2,17 @@ <html lang="en"> <head> <meta charset="UTF-8"> - <title>SSO error</title> + <title>SSO login error</title> </head> <body> - <p>Oops! Something went wrong during authentication<span id="errormsg"></span>.</p> +{# a 403 means we have actively rejected their login #} +{% if code == 403 %} + <p>You are not allowed to log in here.</p> +{% else %} + <p> + There was an error during authentication: + </p> + <div id="errormsg" style="margin:20px 80px">{{ msg }}</div> <p> If you are seeing this page after clicking a link sent to you via email, make sure you only click the confirmation link once, and that you open the @@ -37,9 +44,9 @@ // to print one. let errorDesc = new URLSearchParams(searchStr).get("error_description") if (errorDesc) { - - document.getElementById("errormsg").innerText = ` ("${errorDesc}")`; + document.getElementById("errormsg").innerText = errorDesc; } </script> +{% endif %} </body> -</html> \ No newline at end of file +</html> |