Improve auditing for middleware methods

Populate `username` and `address` fields in middleware audit
entries based on information from the middleware session.

The UI prominently displays the `username` field which is currently
hard-coded to root. This commit adds a helper function to generate
a username string based on the current authenticated credentials
for the session generating the audit entry.

src/middlewared/middlewared/auth.py

@@ -79,6 +79,43 @@ def dump(self):
         }
 
 
+class TokenSessionManagerCredentials(SessionManagerCredentials):
+    def __init__(self, token_manager, token):
+        self.root_credentials = token.root_credentials()
+
+        self.token_manager = token_manager
+        self.token = token
+        self.is_user_session = self.root_credentials.is_user_session
+        if self.is_user_session:
+            self.user = self.root_credentials.user
+
+        self.allowlist = self.root_credentials.allowlist
+
+    def is_valid(self):
+        return self.token.is_valid()
+
+    def authorize(self, method, resource):
+        return self.token.parent_credentials.authorize(method, resource)
+
+    def has_role(self, role):
+        return self.token.parent_credentials.has_role(role)
+
+    def notify_used(self):
+        self.token.notify_used()
+
+    def logout(self):
+        self.token_manager.destroy(self.token)
+
+    def dump(self):
+        data = {
+            "parent": dump_credentials(self.token.parent_credentials),
+        }
+        if self.is_user_session:
+            data["username"] = self.user["username"]
+
+        return data
+
+
 class TrueNasNodeSessionManagerCredentials(SessionManagerCredentials):
     def authorize(self, method, resource):
         return True
@@ -94,3 +131,10 @@ class FakeApplication:
 
 def fake_app():
     return FakeApplication()
+
+
+def dump_credentials(credentials):
+    return {
+        "credentials": credentials.class_name(),
+        "credentials_data": credentials.dump(),
+    }

src/middlewared/middlewared/main.py

@@ -16,6 +16,7 @@
     get_errname,
 )
 from .utils import MIDDLEWARE_RUN_DIR, sw_version
+from .utils.audit import audit_username_from_session
 from .utils.debug import get_frame_details, get_threads_stacks
 from .utils.lock import SoftHardSemaphore, SoftHardSemaphoreLimit
 from .utils.nginx import get_remote_addr_port
@@ -1547,8 +1548,8 @@ async def log_audit_message(self, app, event, event_data, success):
                     "major": 0,
                     "minor": 1
                 },
-                "addr": "127.0.0.1",
-                "user": "root",
+                "addr": app.origin.repr() if isinstance(app.origin, TCPIPOrigin) else "127.0.0.1",
+                "user": audit_username_from_session(app.authenticated_credentials),
                 "sess": app.session_id,
                 "time": datetime.utcnow().strftime('%Y-%m-%d %H:%M:%S.%f'),
                 "svc": "MIDDLEWARE",

src/middlewared/middlewared/plugins/auth.py

@@ -9,7 +9,8 @@
 
 from middlewared.auth import (SessionManagerCredentials, UserSessionManagerCredentials,
                               UnixSocketSessionManagerCredentials, LoginPasswordSessionManagerCredentials,
-                              ApiKeySessionManagerCredentials, TrueNasNodeSessionManagerCredentials)
+                              ApiKeySessionManagerCredentials, TrueNasNodeSessionManagerCredentials,
+                              TokenSessionManagerCredentials, dump_credentials)
 from middlewared.schema import accepts, Any, Bool, Datetime, Dict, Int, List, Password, Patch, Ref, returns, Str
 from middlewared.service import (
     Service, filterable, filterable_returns, filter_list, no_auth_required, no_authz_required,
@@ -143,13 +144,6 @@ def _app_on_close(self, app):
         self.logout(app)
 
 
-def dump_credentials(credentials):
-    return {
-        "credentials": credentials.class_name(),
-        "credentials_data": credentials.dump(),
-    }
-
-
 class Session:
     def __init__(self, manager, credentials, app):
         self.manager = manager
@@ -166,44 +160,6 @@ def dump(self):
         }
 
 
-class TokenSessionManagerCredentials(SessionManagerCredentials):
-    def __init__(self, token_manager, token):
-        root_credentials = token.root_credentials()
-
-        self.token_manager = token_manager
-        self.token = token
-        self.is_user_session = root_credentials.is_user_session
-        if self.is_user_session:
-            self.user = root_credentials.user
-
-        self.allowlist = root_credentials.allowlist
-
-    def is_valid(self):
-        return self.token.is_valid()
-
-    def authorize(self, method, resource):
-        return self.token.parent_credentials.authorize(method, resource)
-
-    def has_role(self, role):
-        return self.token.parent_credentials.has_role(role)
-
-    def notify_used(self):
-        self.token.notify_used()
-
-    def logout(self):
-        self.token_manager.destroy(self.token)
-
-    def dump(self):
-        data = {
-            "parent": dump_credentials(self.token.parent_credentials),
-        }
-        if self.is_user_session:
-            data["username"] = self.user["username"]
-
-        return data
-
-
-
 def is_internal_session(session):
     if isinstance(session.app.origin, UnixSocketOrigin) and session.app.origin.uid == 0:
         return True

src/middlewared/middlewared/pytest/unit/utils/test_audit.py

@@ -0,0 +1,29 @@
+import pytest
+
+from middlewared.auth import (
+    ApiKeySessionManagerCredentials,
+    UserSessionManagerCredentials,
+    TrueNasNodeSessionManagerCredentials
+)
+
+from middlewared.utils.audit import audit_username_from_session
+from types import SimpleNamespace
+
+
+API_KEY = SimpleNamespace(api_key={'id': 1, 'name': 'MY_KEY'})
+
+USER_SESSION = UserSessionManagerCredentials({'username': 'bob', 'privilege': {'allowlist': []}})
+API_KEY_SESSION = ApiKeySessionManagerCredentials(API_KEY)
+TOKEN_USER_SESSION = SimpleNamespace(root_credentials=USER_SESSION, is_user_session=True, user=USER_SESSION.user)
+NODE_SESSION = TrueNasNodeSessionManagerCredentials()
+
+
+@pytest.mark.parametrize('cred,expected', [
+    (None, '.UNAUTHENTICATED'),
+    (USER_SESSION, 'bob'),
+    (API_KEY_SESSION, '.TRUENAS_API_KEY:MY_KEY'),
+    (TOKEN_USER_SESSION, 'bob'),
+    (NODE_SESSION, '.TRUENAS_NODE')
+])
+def test_privilege_has_webui_access(cred, expected):
+    assert audit_username_from_session(cred) == expected

src/middlewared/middlewared/utils/audit.py

@@ -0,0 +1,33 @@
+from middlewared.auth import (
+    ApiKeySessionManagerCredentials,
+    TokenSessionManagerCredentials,
+    TrueNasNodeSessionManagerCredentials
+)
+
+# Special values start with dot to ensure they cannot collide with local usernames
+# created via APIs
+API_KEY_PREFIX = '.TRUENAS_API_KEY:'
+NODE_SESSION = '.TRUENAS_NODE'
+UNAUTHENTICATED = '.UNAUTHENTICATED'
+UNKNOWN_SESSION = '.UNKNOWN'
+
+
+def audit_username_from_session(cred) -> str:
+    if cred is None:
+        return UNAUTHENTICATED
+
+    # This works for regular user session and tokens formed on them
+    if cred.is_user_session:
+        return cred.user['username']
+
+    # Track back to root credential if necessary (token session)
+    if isinstance(cred, TokenSessionManagerCredentials):
+        cred = cred.root_credentials
+
+    if isinstance(cred, ApiKeySessionManagerCredentials):
+        return f'{API_KEY_PREFIX}{cred.api_key.api_key["name"]}'
+
+    elif isinstance(cred, TrueNasNodeSessionManagerCredentials):
+        return NODE_SESSION
+
+    return UNKNOWN_SESSION