Implement pluggable password auth

Allows delegating the password auth to an external module. This also
moves the LDAP auth to using this system, allowing it to be removed from
the synapse tree entirely in the future.

3 files changed, 64 insertions, 103 deletions

diff --git a/synapse/config/homeserver.py b/synapse/config/homeserver.py
index 79b0534b3b..0f890fc04a 100644
--- a/synapse/config/homeserver.py
+++ b/synapse/config/homeserver.py
@@ -30,7 +30,7 @@ from .saml2 import SAML2Config
 from .cas import CasConfig
 from .password import PasswordConfig
 from .jwt import JWTConfig
-from .ldap import LDAPConfig
+from .password_auth_providers import PasswordAuthProviderConfig
 from .emailconfig import EmailConfig
 from .workers import WorkerConfig
 
@@ -39,8 +39,8 @@ class HomeServerConfig(TlsConfig, ServerConfig, DatabaseConfig, LoggingConfig,
                        RatelimitConfig, ContentRepositoryConfig, CaptchaConfig,
                        VoipConfig, RegistrationConfig, MetricsConfig, ApiConfig,
                        AppServiceConfig, KeyConfig, SAML2Config, CasConfig,
-                       JWTConfig, LDAPConfig, PasswordConfig, EmailConfig,
-                       WorkerConfig,):
+                       JWTConfig, PasswordConfig, EmailConfig,
+                       WorkerConfig, PasswordAuthProviderConfig,):
     pass
 
 
diff --git a/synapse/config/ldap.py b/synapse/config/ldap.py
deleted file mode 100644
index d83c2230be..0000000000
--- a/synapse/config/ldap.py
+++ /dev/null
@@ -1,100 +0,0 @@
-# -*- 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, ConfigError
-
-
-MISSING_LDAP3 = (
-    "Missing ldap3 library. This is required for LDAP Authentication."
-)
-
-
-class LDAPMode(object):
-    SIMPLE = "simple",
-    SEARCH = "search",
-
-    LIST = (SIMPLE, SEARCH)
-
-
-class LDAPConfig(Config):
-    def read_config(self, config):
-        ldap_config = config.get("ldap_config", {})
-
-        self.ldap_enabled = ldap_config.get("enabled", False)
-
-        if self.ldap_enabled:
-            # verify dependencies are available
-            try:
-                import ldap3
-                ldap3  # to stop unused lint
-            except ImportError:
-                raise ConfigError(MISSING_LDAP3)
-
-            self.ldap_mode = LDAPMode.SIMPLE
-
-            # verify config sanity
-            self.require_keys(ldap_config, [
-                "uri",
-                "base",
-                "attributes",
-            ])
-
-            self.ldap_uri = ldap_config["uri"]
-            self.ldap_start_tls = ldap_config.get("start_tls", False)
-            self.ldap_base = ldap_config["base"]
-            self.ldap_attributes = ldap_config["attributes"]
-
-            if "bind_dn" in ldap_config:
-                self.ldap_mode = LDAPMode.SEARCH
-                self.require_keys(ldap_config, [
-                    "bind_dn",
-                    "bind_password",
-                ])
-
-                self.ldap_bind_dn = ldap_config["bind_dn"]
-                self.ldap_bind_password = ldap_config["bind_password"]
-                self.ldap_filter = ldap_config.get("filter", None)
-
-            # verify attribute lookup
-            self.require_keys(ldap_config['attributes'], [
-                "uid",
-                "name",
-                "mail",
-            ])
-
-    def require_keys(self, config, required):
-        missing = [key for key in required if key not in config]
-        if missing:
-            raise ConfigError(
-                "LDAP enabled but missing required config values: {}".format(
-                    ", ".join(missing)
-                )
-            )
-
-    def default_config(self, **kwargs):
-        return """\
-        # ldap_config:
-        #   enabled: true
-        #   uri: "ldap://ldap.example.com:389"
-        #   start_tls: true
-        #   base: "ou=users,dc=example,dc=com"
-        #   attributes:
-        #      uid: "cn"
-        #      mail: "email"
-        #      name: "givenName"
-        #   #bind_dn:
-        #   #bind_password:
-        #   #filter: "(objectClass=posixAccount)"
-        """
diff --git a/synapse/config/password_auth_providers.py b/synapse/config/password_auth_providers.py
new file mode 100644
index 0000000000..f6d9bb1c62
--- /dev/null
+++ b/synapse/config/password_auth_providers.py
@@ -0,0 +1,61 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 Openmarket
+#
+# 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
+
+import importlib
+
+
+class PasswordAuthProviderConfig(Config):
+    def read_config(self, config):
+        self.password_providers = []
+
+        # We want to be backwards compatible with the old `ldap_config`
+        # param.
+        ldap_config = config.get("ldap_config", {})
+        self.ldap_enabled = ldap_config.get("enabled", False)
+        if self.ldap_enabled:
+            from synapse.util.ldap_auth_provider import LdapAuthProvider
+            parsed_config = LdapAuthProvider.parse_config(ldap_config)
+            self.password_providers.append((LdapAuthProvider, parsed_config))
+
+        providers = config.get("password_providers", [])
+        for provider in providers:
+            # We need to import the module, and then pick the class out of
+            # that, so we split based on the last dot.
+            module, clz = provider['module'].rsplit(".", 1)
+            module = importlib.import_module(module)
+            provider_class = getattr(module, clz)
+
+            provider_config = provider_class.parse_config(provider["config"])
+            self.password_providers.append((provider_class, provider_config))
+
+    def default_config(self, **kwargs):
+        return """\
+        # password_providers:
+        #     - module: "synapse.util.ldap_auth_provider.LdapAuthProvider"
+        #       config:
+        #         enabled: true
+        #         uri: "ldap://ldap.example.com:389"
+        #         start_tls: true
+        #         base: "ou=users,dc=example,dc=com"
+        #         attributes:
+        #            uid: "cn"
+        #            mail: "email"
+        #            name: "givenName"
+        #         #bind_dn:
+        #         #bind_password:
+        #         #filter: "(objectClass=posixAccount)"
+        """