Equalize Access login failure handling

tests/test_login_security.py

@@ -0,0 +1,87 @@
+from __future__ import annotations
+
+import unittest
+from types import SimpleNamespace
+from unittest.mock import MagicMock, patch
+
+from fastapi import HTTPException
+
+from govoplan_access.backend.api.v1 import auth
+from govoplan_access.backend.security.passwords import (
+    DUMMY_PASSWORD_HASH,
+    verify_password,
+)
+from govoplan_core.api.v1.schemas import LoginRequest
+
+
+class LoginSecurityTests(unittest.TestCase):
+    @staticmethod
+    def _session_with_account(account: object | None) -> MagicMock:
+        session = MagicMock()
+        session.query.return_value.filter.return_value.one_or_none.return_value = (
+            account
+        )
+        return session
+
+    def test_absent_identity_verifies_a_valid_dummy_hash_before_generic_failure(
+        self,
+    ) -> None:
+        self.assertTrue(verify_password("not-a-user-password", DUMMY_PASSWORD_HASH))
+        payload = LoginRequest(
+            email="missing@example.test", password="attempted-password"
+        )
+
+        with patch.object(auth, "verify_password", return_value=True) as verifier:
+            with self.assertRaises(HTTPException) as raised:
+                auth._resolve_login_user(self._session_with_account(None), payload)
+
+        verifier.assert_called_once_with(payload.password, DUMMY_PASSWORD_HASH)
+        self.assertEqual(raised.exception.status_code, 401)
+        self.assertEqual(raised.exception.detail, "Invalid login")
+
+    def test_present_identity_verifies_account_hash_before_same_generic_failure(
+        self,
+    ) -> None:
+        account_hash = "pbkdf2_sha256$260000$account-salt$account-digest"
+        account = SimpleNamespace(password_hash=account_hash)
+        payload = LoginRequest(email="known@example.test", password="wrong-password")
+
+        with patch.object(auth, "verify_password", return_value=False) as verifier:
+            with self.assertRaises(HTTPException) as raised:
+                auth._resolve_login_user(self._session_with_account(account), payload)  # type: ignore[arg-type]
+
+        verifier.assert_called_once_with(payload.password, account_hash)
+        self.assertEqual(raised.exception.status_code, 401)
+        self.assertEqual(raised.exception.detail, "Invalid login")
+
+    def test_passwordless_account_cannot_authenticate_with_dummy_password(self) -> None:
+        account = SimpleNamespace(password_hash=None)
+        payload = LoginRequest(
+            email="passwordless@example.test", password="not-a-user-password"
+        )
+
+        with self.assertRaises(HTTPException) as raised:
+            auth._resolve_login_user(self._session_with_account(account), payload)  # type: ignore[arg-type]
+
+        self.assertEqual(raised.exception.status_code, 401)
+        self.assertEqual(raised.exception.detail, "Invalid login")
+
+    def test_account_without_active_membership_uses_same_generic_failure(self) -> None:
+        account = SimpleNamespace(
+            id="account-1",
+            password_hash="pbkdf2_sha256$260000$account-salt$account-digest",
+        )
+        session = self._session_with_account(account)
+        session.query.return_value.join.return_value.filter.return_value.order_by.return_value.first.return_value = None
+        payload = LoginRequest(email="known@example.test", password="correct-password")
+
+        with patch.object(auth, "verify_password", return_value=True):
+            with self.assertRaises(HTTPException) as raised:
+                auth._resolve_login_user(session, payload)  # type: ignore[arg-type]
+
+        self.assertEqual(raised.exception.status_code, 401)
+        self.assertEqual(raised.exception.detail, "Invalid login")
+
+
+if __name__ == "__main__":
+    unittest.main()