Merge pull request #701 from DoubleMalt/ldap-auth

Add LDAP authentication

AUTHORS.rst

@@ -57,3 +57,6 @@ Florent Violleau <floviolleau at gmail dot com>
 
 Niklas Riekenbrauck <nikriek at gmail dot.com>
  * Add JWT support for registration and login
+
+Christoph Witzany <christoph at web.crofting.com>
+ * Add LDAP support for authentication

synapse/config/homeserver.py

@@ -30,13 +30,14 @@ from .saml2 import SAML2Config
 from .cas import CasConfig
 from .password import PasswordConfig
 from .jwt import JWTConfig
+from .ldap import LDAPConfig
 
 
 class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
                        RatelimitConfig, ContentRepositoryConfig, CaptchaConfig,
                        VoipConfig, RegistrationConfig, MetricsConfig, ApiConfig,
                        AppServiceConfig, KeyConfig, SAML2Config, CasConfig,
-                       JWTConfig, PasswordConfig,):
+                       JWTConfig, LDAPConfig, PasswordConfig,):
     pass
 
 

synapse/config/ldap.py

@@ -0,0 +1,52 @@
+# -*- coding: utf-8 -*-
+# Copyright 2015 Niklas Riekenbrauck
+#
+# 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 ._base import Config
+
+
+class LDAPConfig(Config):
+    def read_config(self, config):
+        ldap_config = config.get("ldap_config", None)
+        if ldap_config:
+            self.ldap_enabled = ldap_config.get("enabled", False)
+            self.ldap_server = ldap_config["server"]
+            self.ldap_port = ldap_config["port"]
+            self.ldap_tls = ldap_config.get("tls", False)
+            self.ldap_search_base = ldap_config["search_base"]
+            self.ldap_search_property = ldap_config["search_property"]
+            self.ldap_email_property = ldap_config["email_property"]
+            self.ldap_full_name_property = ldap_config["full_name_property"]
+        else:
+            self.ldap_enabled = False
+            self.ldap_server = None
+            self.ldap_port = None
+            self.ldap_tls = False
+            self.ldap_search_base = None
+            self.ldap_search_property = None
+            self.ldap_email_property = None
+            self.ldap_full_name_property = None
+
+    def default_config(self, **kwargs):
+        return """\
+        # ldap_config:
+        #   enabled: true
+        #   server: "ldap://localhost"
+        #   port: 389
+        #   tls: false
+        #   search_base: "ou=Users,dc=example,dc=com"
+        #   search_property: "cn"
+        #   email_property: "email"
+        #   full_name_property: "givenName"
+        """

synapse/handlers/auth.py

@@ -49,6 +49,21 @@ class AuthHandler(BaseHandler):
         self.sessions = {}
         self.INVALID_TOKEN_HTTP_STATUS = 401
 
+        self.ldap_enabled = hs.config.ldap_enabled
+        self.ldap_server = hs.config.ldap_server
+        self.ldap_port = hs.config.ldap_port
+        self.ldap_tls = hs.config.ldap_tls
+        self.ldap_search_base = hs.config.ldap_search_base
+        self.ldap_search_property = hs.config.ldap_search_property
+        self.ldap_email_property = hs.config.ldap_email_property
+        self.ldap_full_name_property = hs.config.ldap_full_name_property
+
+        if self.ldap_enabled is True:
+            import ldap
+            logger.info("Import ldap version: %s", ldap.__version__)
+
+        self.hs = hs  # FIXME better possibility to access registrationHandler later?
+
     @defer.inlineCallbacks
     def check_auth(self, flows, clientdict, clientip):
         """
@@ -215,8 +230,10 @@ class AuthHandler(BaseHandler):
         if not user_id.startswith('@'):
             user_id = UserID.create(user_id, self.hs.hostname).to_string()
 
-        user_id, password_hash = yield self._find_user_id_and_pwd_hash(user_id)
-        self._check_password(user_id, password, password_hash)
+        if not (yield self._check_password(user_id, password)):
+            logger.warn("Failed password login for user %s", user_id)
+            raise LoginError(403, "", errcode=Codes.FORBIDDEN)
+
         defer.returnValue(user_id)
 
     @defer.inlineCallbacks
@@ -340,8 +357,10 @@ class AuthHandler(BaseHandler):
             StoreError if there was a problem storing the token.
             LoginError if there was an authentication problem.
         """
-        user_id, password_hash = yield self._find_user_id_and_pwd_hash(user_id)
-        self._check_password(user_id, password, password_hash)
+
+        if not (yield self._check_password(user_id, password)):
+            logger.warn("Failed password login for user %s", user_id)
+            raise LoginError(403, "", errcode=Codes.FORBIDDEN)
 
         logger.info("Logging in user %s", user_id)
         access_token = yield self.issue_access_token(user_id)
@@ -407,11 +426,60 @@ class AuthHandler(BaseHandler):
         else:
             defer.returnValue(user_infos.popitem())
 
-    def _check_password(self, user_id, password, stored_hash):
-        """Checks that user_id has passed password, raises LoginError if not."""
-        if not self.validate_hash(password, stored_hash):
-            logger.warn("Failed password login for user %s", user_id)
-            raise LoginError(403, "", errcode=Codes.FORBIDDEN)
+    @defer.inlineCallbacks
+    def _check_password(self, user_id, password):
+        defer.returnValue(
+            not (
+                (yield self._check_ldap_password(user_id, password))
+                or
+                (yield self._check_local_password(user_id, password))
+            ))
+
+    @defer.inlineCallbacks
+    def _check_local_password(self, user_id, password):
+        try:
+            user_id, password_hash = yield self._find_user_id_and_pwd_hash(user_id)
+            defer.returnValue(not self.validate_hash(password, password_hash))
+        except LoginError:
+            defer.returnValue(False)
+
+    @defer.inlineCallbacks
+    def _check_ldap_password(self, user_id, password):
+        if self.ldap_enabled is not True:
+            logger.debug("LDAP not configured")
+            defer.returnValue(False)
+
+        import ldap
+
+        logger.info("Authenticating %s with LDAP" % user_id)
+        try:
+            ldap_url = "%s:%s" % (self.ldap_server, self.ldap_port)
+            logger.debug("Connecting LDAP server at %s" % ldap_url)
+            l = ldap.initialize(ldap_url)
+            if self.ldap_tls:
+                logger.debug("Initiating TLS")
+                self._connection.start_tls_s()
+
+            local_name = UserID.from_string(user_id).localpart
+
+            dn = "%s=%s, %s" % (
+                self.ldap_search_property,
+                local_name,
+                self.ldap_search_base)
+            logger.debug("DN for LDAP authentication: %s" % dn)
+
+            l.simple_bind_s(dn.encode('utf-8'), password.encode('utf-8'))
+
+            if not (yield self.does_user_exist(user_id)):
+                handler = self.hs.get_handlers().registration_handler
+                user_id, access_token = (
+                    yield handler.register(localpart=local_name)
+                )
+
+            defer.returnValue(True)
+        except ldap.LDAPError, e:
+            logger.warn("LDAP error: %s", e)
+            defer.returnValue(False)
 
     @defer.inlineCallbacks
     def issue_access_token(self, user_id):