Merge pull request #4 from alan-turing-institute/3-respond-to-all-req…

…uests

Respond to all requests

.gitignore

@@ -1,3 +1,7 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+
 # OS files
 .DS_Store
 

README.md

@@ -8,7 +8,42 @@ The name is a slightly tortured acronym for: LD**A**P **pr**oxy for Open**I**D *
 Start the `Apricot` server on port 8080 by running:
 
 ```bash
-python run.py --client-id "<your client ID>" --client-secret "<your client secret>" --backend <your backend> --port 8080
+python run.py --client-id "<your client ID>" --client-secret "<your client secret>" --backend "<your backend>" --port 8080 --domain "<your domain name>"
+```
+
+This will create an LDAP tree that looks like this:
+
+```ldif
+dn: DC=<your domain>
+objectClass: dcObject
+
+dn: OU=users,DC=<your domain>
+objectClass: organizationalUnit
+ou: users
+
+dn: OU=groups,DC=<your domain>
+objectClass: organizationalUnit
+ou: groups
+```
+
+Each user will have an entry like
+
+```ldif
+dn: CN=<user name>,OU=users,DC=<your domain>
+objectClass: organizationalPerson
+objectClass: person
+objectClass: top
+objectClass: user
+<user data fields here>
+```
+
+Each group will have an entry like
+
+```ldif
+dn: CN=<group name>,OU=groups,DC=<your domain>
+objectClass: group
+objectClass: top
+<group data fields here>
 ```
 
 ## OpenID Connect

apricot/apricot_server.py

@@ -16,6 +16,7 @@ def __init__(
         backend: OAuthBackend,
         client_id: str,
         client_secret: str,
+        domain: str,
         port: int,
         **kwargs: Any,
     ) -> None:
@@ -25,7 +26,10 @@ def __init__(
         # Initialize the appropriate OAuth client
         try:
             oauth_client = OAuthClientMap[backend](
-                client_id=client_id, client_secret=client_secret, **kwargs
+                client_id=client_id,
+                client_secret=client_secret,
+                domain=domain,
+                **kwargs,
             )
         except Exception as exc:
             msg = f"Could not construct an OAuth client for the '{backend}' backend."

apricot/ldap/oauth_ldap_entry.py

@@ -41,7 +41,12 @@ def __str__(self) -> str:
         output = bytes(self.toWire()).decode("utf-8")
         for child in self._children.values():
             try:
-                output += f"\n- {child!s}"
+                # Indent children by two spaces
+                indent = "  "
+                output += (
+                    f"{indent}{str(child).strip()}".replace("\n", f"\n{indent}")
+                    + "\n\n"
+                )
             except TypeError:
                 pass
         return output

apricot/ldap/oauth_ldap_server_factory.py

@@ -1,14 +1,14 @@
-from ldaptor.protocols.ldap.ldapserver import LDAPServer
 from twisted.internet.interfaces import IAddress
 from twisted.internet.protocol import Protocol, ServerFactory
 
 from apricot.oauth import OAuthClient
 
 from .oauth_ldap_tree import OAuthLDAPTree
+from .read_only_ldap_server import ReadOnlyLDAPServer
 
 
 class OAuthLDAPServerFactory(ServerFactory):
-    protocol = LDAPServer
+    protocol = ReadOnlyLDAPServer
 
     def __init__(self, oauth_client: OAuthClient):
         """

apricot/ldap/oauth_ldap_tree.py

@@ -20,9 +20,8 @@ def __init__(self, oauth_client: OAuthClient) -> None:
         self.oauth_client = oauth_client
 
         # Create a root node for the tree
-        root_dn = "DC=" + self.oauth_client.domain().replace(".", ",DC=")
         self.root = self.build_root(
-            dn=root_dn, attributes={"objectClass": ["dcObject"]}
+            dn=self.oauth_client.root_dn, attributes={"objectClass": ["dcObject"]}
         )
         # Add OUs for users and groups
         groups_ou = self.root.add_child(

apricot/ldap/read_only_ldap_server.py

@@ -0,0 +1,111 @@
+from typing import Callable
+
+from ldaptor.interfaces import ILDAPEntry
+from ldaptor.protocols.ldap.ldaperrors import LDAPProtocolError
+from ldaptor.protocols.ldap.ldapserver import LDAPServer
+from ldaptor.protocols.pureldap import (
+    LDAPBindRequest,
+    LDAPControl,
+    LDAPSearchResultDone,
+    LDAPSearchResultEntry,
+)
+from twisted.internet import defer
+
+
+class ReadOnlyLDAPServer(LDAPServer):
+    def getRootDSE(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        reply: Callable[[LDAPSearchResultEntry], None] | None,
+    ) -> LDAPSearchResultDone:
+        """Handle an LDAP Root RSE request"""
+        return super().getRootDSE(request, reply)
+
+    def handle_LDAPAddRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Refuse to handle an LDAP add request"""
+        id((request, controls, reply))  # ignore unused arguments
+        msg = "ReadOnlyLDAPServer will not handle LDAP add requests"
+        raise LDAPProtocolError(msg)
+
+    def handle_LDAPBindRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Handle an LDAP bind request"""
+        return super().handle_LDAPBindRequest(request, controls, reply)
+
+    def handle_LDAPCompareRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Handle an LDAP compare request"""
+        return super().handle_LDAPCompareRequest(request, controls, reply)
+
+    def handle_LDAPDelRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Refuse to handle an LDAP delete request"""
+        id((request, controls, reply))  # ignore unused arguments
+        msg = "ReadOnlyLDAPServer will not handle LDAP delete requests"
+        raise LDAPProtocolError(msg)
+
+    def handle_LDAPExtendedRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Handle an LDAP extended request"""
+        return super().handle_LDAPExtendedRequest(request, controls, reply)
+
+    def handle_LDAPModifyDNRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Refuse to handle an LDAP modify DN request"""
+        id((request, controls, reply))  # ignore unused arguments
+        msg = "ReadOnlyLDAPServer will not handle LDAP modify DN requests"
+        raise LDAPProtocolError(msg)
+
+    def handle_LDAPModifyRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Refuse to handle an LDAP modify request"""
+        id((request, controls, reply))  # ignore unused arguments
+        msg = "ReadOnlyLDAPServer will not handle LDAP modify requests"
+        raise LDAPProtocolError(msg)
+
+    def handle_LDAPUnbindRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[..., None] | None,
+    ) -> None:
+        """Handle an LDAP unbind request"""
+        super().handle_LDAPUnbindRequest(request, controls, reply)
+
+    def handle_LDAPSearchRequest(  # noqa: N802
+        self,
+        request: LDAPBindRequest,
+        controls: LDAPControl | None,
+        reply: Callable[[LDAPSearchResultEntry], None] | None,
+    ) -> defer.Deferred[ILDAPEntry]:
+        """Handle an LDAP search request"""
+        return super().handle_LDAPSearchRequest(request, controls, reply)

apricot/oauth/microsoft_entra_client.py

@@ -9,33 +9,19 @@ class MicrosoftEntraClient(OAuthClient):
 
     def __init__(
         self,
-        client_id: str,
-        client_secret: str,
         entra_tenant_id: str,
         **kwargs: Any,
     ):
-        del kwargs  # consume any unused arguments
         redirect_uri = "urn:ietf:wg:oauth:2.0:oob"  # this is the "no redirect" URL
         scopes = ["https://graph.microsoft.com/.default"]  # this is the default scope
         token_url = (
             f"https://login.microsoftonline.com/{entra_tenant_id}/oauth2/v2.0/token"
         )
         self.tenant_id = entra_tenant_id
         super().__init__(
-            client_id=client_id,
-            client_secret=client_secret,
-            redirect_uri=redirect_uri,
-            scopes=scopes,
-            token_url=token_url,
+            redirect_uri=redirect_uri, scopes=scopes, token_url=token_url, **kwargs
         )
 
-    def domain(self) -> str:
-        users = self.users()
-        domains = {str(user["domain"][0]) for user in users}
-        if len(domains) > 1:
-            domains = {domain for domain in domains if "onmicrosoft.com" not in domain}
-        return sorted(domains)[0]
-
     def extract_token(self, json_response: JSONDict) -> str:
         return str(json_response["access_token"])
 
@@ -68,7 +54,7 @@ def users(self) -> list[LDAPAttributeDict]:
                     f"https://graph.microsoft.com/v1.0/users/{user_dict['id']}/memberOf"
                 )
                 attributes["memberOf"] = [
-                    group["displayName"]
+                    f"CN={group['displayName']},OU=groups,{self.root_dn}"
                     for group in group_memberships["value"]
                     if group["displayName"]
                 ]

apricot/oauth/oauth_client.py

@@ -20,10 +20,15 @@ def __init__(
         self,
         client_id: str,
         client_secret: str,
+        domain: str,
         redirect_uri: str,
         scopes: list[str],
         token_url: str,
     ) -> None:
+        # Set attributes
+        self.client_secret = client_secret
+        self.domain = domain
+        self.token_url = token_url
         # Allow token scope to not match requested scope. (Other auth libraries allow
         # this, but Requests-OAuthlib raises exception on scope mismatch by default.)
         os.environ["OAUTHLIB_RELAX_TOKEN_SCOPE"] = "1"  # noqa: S105
@@ -40,9 +45,6 @@ def __init__(
                 client_id=client_id, scope=scopes, redirect_uri=redirect_uri
             )
         )
-        # Store client secret and token URL
-        self.client_secret = client_secret
-        self.token_url = token_url
         # Request a new bearer token
         json_response = self.session_application.fetch_token(
             token_url=self.token_url,
@@ -51,10 +53,6 @@ def __init__(
         )
         self.bearer_token = self.extract_token(json_response)
 
-    @abstractmethod
-    def domain(self) -> str:
-        pass
-
     @abstractmethod
     def extract_token(self, json_response: JSONDict) -> str:
         pass
@@ -67,6 +65,10 @@ def groups(self) -> list[LDAPAttributeDict]:
     def users(self) -> list[LDAPAttributeDict]:
         pass
 
+    @property
+    def root_dn(self) -> str:
+        return "DC=" + self.domain.replace(".", ",DC=")
+
     def query(self, url: str) -> dict[str, Any]:
         result = self.session_application.request(
             method="GET",

run.py

@@ -8,12 +8,15 @@
         prog="Apricot",
         description="Apricot is a proxy for delegating LDAP requests to an OpenID Connect backend.",
     )
-    parser.add_argument("-b", "--backend", type=OAuthBackend, help="Which OAuth backend to use")
-    parser.add_argument("-p", "--port", type=int, default=8080, help="Port to run on")
-    parser.add_argument("-i", "--client-id", type=str, help="OAuth client ID")
-    parser.add_argument("-s", "--client-secret", type=str, help="OAuth client secret")
-    parser.add_argument("-t", "--entra-tenant-id", type=str, help="Microsoft Entra tenant id")
-
+    # Common options needed for all backends
+    parser.add_argument("-b", "--backend", type=OAuthBackend, help="Which OAuth backend to use.")
+    parser.add_argument("-d", "--domain", type=str, help="Which domain users belong to.")
+    parser.add_argument("-p", "--port", type=int, default=8080, help="Port to run on.")
+    parser.add_argument("-i", "--client-id", type=str, help="OAuth client ID.")
+    parser.add_argument("-s", "--client-secret", type=str, help="OAuth client secret.")
+    # Options for Microsoft Entra backend
+    parser.add_argument("-t", "--entra-tenant-id", type=str, help="Microsoft Entra tenant ID.", required=False)
+    # Parse arguments
     args = parser.parse_args()
 
     # Create the Apricot server