Add security hardening and additional auth tests

Security improvements:
- Add password strength validation (min 8 characters)
- Invalidate all sessions on password change/reset
- Add timing-safe user lookup to prevent enumeration attacks
- Fix SQLAlchemy boolean comparisons (== True -> is_(True))
- Change default admin password to 'changeme123' (meets min length)

New tests (7 additional):
- Inactive user login attempt blocked
- Short password rejected on create/change/reset
- Duplicate username rejected (409)
- Non-owner API key deletion blocked (403)
- Sessions invalidated on password change

backend/app/auth.py

@@ -22,6 +22,26 @@ API_KEY_PREFIX = "orch_"
 # Session duration (24 hours default)
 SESSION_DURATION_HOURS = 24
 
+# Password requirements
+MIN_PASSWORD_LENGTH = 8
+
+
+class PasswordTooShortError(ValueError):
+    """Raised when password doesn't meet minimum length requirement."""
+
+    pass
+
+
+def validate_password_strength(password: str) -> None:
+    """Validate password meets minimum requirements.
+
+    Raises PasswordTooShortError if password is too short.
+    """
+    if not password or len(password) < MIN_PASSWORD_LENGTH:
+        raise PasswordTooShortError(
+            f"Password must be at least {MIN_PASSWORD_LENGTH} characters"
+        )
+
 
 def hash_password(password: str) -> str:
     """Hash a password using bcrypt."""
@@ -93,23 +113,37 @@ class AuthService:
         """Authenticate a user with username and password.
 
         Returns the user if authentication succeeds, None otherwise.
+        Uses constant-time comparison to prevent timing-based user enumeration.
         """
         user = self.get_user_by_username(username)
+        
+        # Always perform password verification to prevent timing attacks
+        # Use a dummy hash if user doesn't exist
+        dummy_hash = "$2b$12$LQv3c1yqBWVHxkd0LHAkCOYz6TtxMQJqhN8/X4.VTtYA1vQ9S9sXa"
+        password_hash = user.password_hash if user and user.password_hash else dummy_hash
+        
+        # Verify password (constant time even if user doesn't exist)
+        password_valid = verify_password(password, password_hash)
+        
+        # Check all conditions
         if not user:
             return None
         if not user.password_hash:
             return None  # OIDC-only user
         if not user.is_active:
             return None
-        if not verify_password(password, user.password_hash):
+        if not password_valid:
             return None
         return user
 
     def change_password(self, user: User, new_password: str) -> None:
-        """Change a user's password."""
+        """Change a user's password and invalidate all existing sessions."""
+        validate_password_strength(new_password)
         user.password_hash = hash_password(new_password)
         user.must_change_password = False
         self.db.commit()
+        # Invalidate all existing sessions for security
+        self.delete_user_sessions(user)
 
     def update_last_login(self, user: User) -> None:
         """Update the user's last login timestamp."""
@@ -120,7 +154,7 @@ class AuthService:
         """List all users."""
         query = self.db.query(User)
         if not include_inactive:
-            query = query.filter(User.is_active == True)
+            query = query.filter(User.is_active.is_(True))
         return query.order_by(User.username).all()
 
     def set_user_active(self, user: User, is_active: bool) -> None:
@@ -134,10 +168,13 @@ class AuthService:
         self.db.commit()
 
     def reset_user_password(self, user: User, new_password: str) -> None:
-        """Reset a user's password (admin action)."""
+        """Reset a user's password (admin action) and invalidate all sessions."""
+        validate_password_strength(new_password)
         user.password_hash = hash_password(new_password)
         user.must_change_password = True
         self.db.commit()
+        # Invalidate all existing sessions for security
+        self.delete_user_sessions(user)
 
     # --- Session Operations ---
 
@@ -159,7 +196,8 @@ class AuthService:
         session = UserSession(
             user_id=user.id,
             token_hash=token_hash,
-            expires_at=datetime.now(timezone.utc) + timedelta(hours=SESSION_DURATION_HOURS),
+            expires_at=datetime.now(timezone.utc)
+            + timedelta(hours=SESSION_DURATION_HOURS),
             user_agent=user_agent,
             ip_address=ip_address,
         )
@@ -328,7 +366,7 @@ def create_default_admin(db: Session) -> Optional[User]:
     auth_service = AuthService(db)
     admin = auth_service.create_user(
         username="admin",
-        password="admin",
+        password="changeme123",
         is_admin=True,
         must_change_password=True,
     )

backend/app/main.py

@@ -27,7 +27,7 @@ async def lifespan(app: FastAPI):
         admin = create_default_admin(db)
         if admin:
             logger.warning(
-                "Default admin user created with username 'admin' and password 'admin'. "
+                "Default admin user created with username 'admin' and password 'changeme123'. "
                 "CHANGE THIS PASSWORD IMMEDIATELY!"
             )
     finally:

backend/app/routes.py

@@ -368,6 +368,9 @@ from .auth import (
     get_auth_service,
     SESSION_COOKIE_NAME,
     verify_password,
+    validate_password_strength,
+    PasswordTooShortError,
+    MIN_PASSWORD_LENGTH,
 )
 
 
@@ -491,8 +494,14 @@ def change_password(
             detail="Current password is incorrect",
         )
 
-    # Change password
+    # Validate and change password
-    auth_service.change_password(current_user, password_request.new_password)
+    try:
+        auth_service.change_password(current_user, password_request.new_password)
+    except PasswordTooShortError:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail=f"Password must be at least {MIN_PASSWORD_LENGTH} characters",
+        )
 
     # Log audit
     _log_audit(
@@ -659,6 +668,15 @@ def create_user(
             detail="Username already exists",
         )
 
+    # Validate password strength
+    try:
+        validate_password_strength(user_create.password)
+    except PasswordTooShortError:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail=f"Password must be at least {MIN_PASSWORD_LENGTH} characters",
+        )
+
     user = auth_service.create_user(
         username=user_create.username,
         password=user_create.password,
@@ -738,7 +756,7 @@ def update_user(
     if user_update.is_admin is False and user.is_admin:
         admin_count = (
             auth_service.db.query(User)
-            .filter(User.is_admin == True, User.is_active == True)
+            .filter(User.is_admin.is_(True), User.is_active.is_(True))
             .count()
         )
         if admin_count <= 1:
@@ -798,7 +816,13 @@ def reset_user_password(
             detail="User not found",
         )
 
-    auth_service.reset_user_password(user, reset_request.new_password)
+    try:
+        auth_service.reset_user_password(user, reset_request.new_password)
+    except PasswordTooShortError:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail=f"Password must be at least {MIN_PASSWORD_LENGTH} characters",
+        )
 
     # Log audit
     _log_audit(

backend/tests/integration/test_auth_api.py

@@ -12,7 +12,7 @@ class TestAuthLogin:
         """Test successful login with default admin credentials."""
         response = integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         assert response.status_code == 200
         data = response.json()
@@ -49,7 +49,7 @@ class TestAuthLogout:
         # First login
         login_response = integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         assert login_response.status_code == 200
 
@@ -75,7 +75,7 @@ class TestAuthMe:
         # Login first
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         response = integration_client.get("/api/v1/auth/me")
@@ -106,13 +106,13 @@ class TestAuthChangePassword:
         # Login first
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         # Change password
         response = integration_client.post(
             "/api/v1/auth/change-password",
-            json={"current_password": "admin", "new_password": "newpassword123"},
+            json={"current_password": "changeme123", "new_password": "newpassword123"},
         )
         assert response.status_code == 200
 
@@ -120,7 +120,7 @@ class TestAuthChangePassword:
         integration_client.cookies.clear()
         response = integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         assert response.status_code == 401
 
@@ -132,10 +132,11 @@ class TestAuthChangePassword:
         assert response.status_code == 200
 
         # Reset password back to original for other tests
-        integration_client.post(
+        reset_response = integration_client.post(
             "/api/v1/auth/change-password",
-            json={"current_password": "newpassword123", "new_password": "admin"},
+            json={"current_password": "newpassword123", "new_password": "changeme123"},
         )
+        assert reset_response.status_code == 200, "Failed to reset admin password back to default"
 
     @pytest.mark.integration
     def test_change_password_wrong_current(self, integration_client):
@@ -143,7 +144,7 @@ class TestAuthChangePassword:
         # Login first
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         response = integration_client.post(
@@ -163,7 +164,7 @@ class TestAPIKeys:
         # Login first
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         # Create API key
@@ -195,7 +196,7 @@ class TestAPIKeys:
         # Login and create API key
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         create_response = integration_client.post(
             "/api/v1/auth/keys",
@@ -216,7 +217,7 @@ class TestAPIKeys:
         # Clean up
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         integration_client.delete(f"/api/v1/auth/keys/{key_id}")
 
@@ -226,7 +227,7 @@ class TestAPIKeys:
         # Login and create API key
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         create_response = integration_client.post(
             "/api/v1/auth/keys",
@@ -257,7 +258,7 @@ class TestAdminUserManagement:
         # Login as admin
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         response = integration_client.get("/api/v1/admin/users")
@@ -272,7 +273,7 @@ class TestAdminUserManagement:
         # Login as admin
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         # Create new user
@@ -305,7 +306,7 @@ class TestAdminUserManagement:
         # Login as admin
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         # Create a test user
@@ -331,7 +332,7 @@ class TestAdminUserManagement:
         # Login as admin
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
 
         # Create a test user
@@ -362,7 +363,7 @@ class TestAdminUserManagement:
         # Login as admin and create non-admin user
         integration_client.post(
             "/api/v1/auth/login",
-            json={"username": "admin", "password": "admin"},
+            json={"username": "admin", "password": "changeme123"},
         )
         test_username = f"nonadmin_{uuid4().hex[:8]}"
         integration_client.post(
@@ -381,3 +382,379 @@ class TestAdminUserManagement:
         response = integration_client.get("/api/v1/admin/users")
         assert response.status_code == 403
         assert "Admin privileges required" in response.json()["detail"]
+
+
+class TestSecurityEdgeCases:
+    """Tests for security edge cases and validation."""
+
+    @pytest.mark.integration
+    def test_login_inactive_user(self, integration_client):
+        """Test that inactive users cannot login."""
+        # Login as admin and create a user
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        test_username = f"inactive_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Deactivate the user
+        integration_client.put(
+            f"/api/v1/admin/users/{test_username}",
+            json={"is_active": False},
+        )
+
+        # Try to login as inactive user
+        integration_client.cookies.clear()
+        response = integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": test_username, "password": "password123"},
+        )
+        assert response.status_code == 401
+        assert "Invalid username or password" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_password_too_short_on_create(self, integration_client):
+        """Test that short passwords are rejected when creating users."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        response = integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": f"shortpw_{uuid4().hex[:8]}", "password": "short"},
+        )
+        assert response.status_code == 400
+        assert "at least 8 characters" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_password_too_short_on_change(self, integration_client):
+        """Test that short passwords are rejected when changing password."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        response = integration_client.post(
+            "/api/v1/auth/change-password",
+            json={"current_password": "changeme123", "new_password": "short"},
+        )
+        assert response.status_code == 400
+        assert "at least 8 characters" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_password_too_short_on_reset(self, integration_client):
+        """Test that short passwords are rejected when resetting password."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        # Create a test user first
+        test_username = f"resetshort_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        response = integration_client.post(
+            f"/api/v1/admin/users/{test_username}/reset-password",
+            json={"new_password": "short"},
+        )
+        assert response.status_code == 400
+        assert "at least 8 characters" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_duplicate_username_rejected(self, integration_client):
+        """Test that duplicate usernames are rejected."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        test_username = f"duplicate_{uuid4().hex[:8]}"
+        # Create user first time
+        response1 = integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+        assert response1.status_code == 200
+
+        # Try to create same username again
+        response2 = integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password456"},
+        )
+        assert response2.status_code == 409
+        assert "already exists" in response2.json()["detail"]
+
+    @pytest.mark.integration
+    def test_cannot_delete_other_users_api_key(self, integration_client):
+        """Test that users cannot delete API keys owned by other users."""
+        # Login as admin and create an API key
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        create_response = integration_client.post(
+            "/api/v1/auth/keys",
+            json={"name": "admin-key"},
+        )
+        admin_key_id = create_response.json()["id"]
+
+        # Create a non-admin user
+        test_username = f"nonadmin_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Login as non-admin
+        integration_client.cookies.clear()
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Try to delete admin's API key
+        response = integration_client.delete(f"/api/v1/auth/keys/{admin_key_id}")
+        assert response.status_code == 403
+        assert "Cannot delete another user's API key" in response.json()["detail"]
+
+        # Cleanup: login as admin and delete the key
+        integration_client.cookies.clear()
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        integration_client.delete(f"/api/v1/auth/keys/{admin_key_id}")
+
+    @pytest.mark.integration
+    def test_sessions_invalidated_on_password_change(self, integration_client):
+        """Test that all sessions are invalidated when password is changed."""
+        # Create a test user
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        test_username = f"sessiontest_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Login as test user
+        integration_client.cookies.clear()
+        login_response = integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": test_username, "password": "password123"},
+        )
+        assert login_response.status_code == 200
+
+        # Verify session works
+        me_response = integration_client.get("/api/v1/auth/me")
+        assert me_response.status_code == 200
+
+        # Change password
+        integration_client.post(
+            "/api/v1/auth/change-password",
+            json={"current_password": "password123", "new_password": "newpassword123"},
+        )
+
+        # Old session should be invalidated - try to access /me
+        # (note: the change-password call itself may have cleared the session cookie)
+        me_response2 = integration_client.get("/api/v1/auth/me")
+        # This should fail because all sessions were invalidated
+        assert me_response2.status_code == 401
+
+
+class TestSecurityEdgeCases:
+    """Tests for security edge cases and validation."""
+
+    @pytest.mark.integration
+    def test_login_inactive_user(self, integration_client):
+        """Test that inactive users cannot login."""
+        # Login as admin and create a user
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        test_username = f"inactive_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Deactivate the user
+        integration_client.put(
+            f"/api/v1/admin/users/{test_username}",
+            json={"is_active": False},
+        )
+
+        # Try to login as inactive user
+        integration_client.cookies.clear()
+        response = integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": test_username, "password": "password123"},
+        )
+        assert response.status_code == 401
+        assert "Invalid username or password" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_password_too_short_on_create(self, integration_client):
+        """Test that short passwords are rejected when creating users."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        response = integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": f"shortpw_{uuid4().hex[:8]}", "password": "short"},
+        )
+        assert response.status_code == 400
+        assert "at least 8 characters" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_password_too_short_on_change(self, integration_client):
+        """Test that short passwords are rejected when changing password."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        response = integration_client.post(
+            "/api/v1/auth/change-password",
+            json={"current_password": "changeme123", "new_password": "short"},
+        )
+        assert response.status_code == 400
+        assert "at least 8 characters" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_password_too_short_on_reset(self, integration_client):
+        """Test that short passwords are rejected when resetting password."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        # Create a test user first
+        test_username = f"resetshort_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        response = integration_client.post(
+            f"/api/v1/admin/users/{test_username}/reset-password",
+            json={"new_password": "short"},
+        )
+        assert response.status_code == 400
+        assert "at least 8 characters" in response.json()["detail"]
+
+    @pytest.mark.integration
+    def test_duplicate_username_rejected(self, integration_client):
+        """Test that duplicate usernames are rejected."""
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+
+        test_username = f"duplicate_{uuid4().hex[:8]}"
+        # Create user first time
+        response1 = integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+        assert response1.status_code == 200
+
+        # Try to create same username again
+        response2 = integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password456"},
+        )
+        assert response2.status_code == 409
+        assert "already exists" in response2.json()["detail"]
+
+    @pytest.mark.integration
+    def test_cannot_delete_other_users_api_key(self, integration_client):
+        """Test that users cannot delete API keys owned by other users."""
+        # Login as admin and create an API key
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        create_response = integration_client.post(
+            "/api/v1/auth/keys",
+            json={"name": "admin-key"},
+        )
+        admin_key_id = create_response.json()["id"]
+
+        # Create a non-admin user
+        test_username = f"nonadmin_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Login as non-admin
+        integration_client.cookies.clear()
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Try to delete admin's API key
+        response = integration_client.delete(f"/api/v1/auth/keys/{admin_key_id}")
+        assert response.status_code == 403
+        assert "Cannot delete another user's API key" in response.json()["detail"]
+
+        # Cleanup: login as admin and delete the key
+        integration_client.cookies.clear()
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        integration_client.delete(f"/api/v1/auth/keys/{admin_key_id}")
+
+    @pytest.mark.integration
+    def test_sessions_invalidated_on_password_change(self, integration_client):
+        """Test that all sessions are invalidated when password is changed."""
+        # Create a test user
+        integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": "admin", "password": "changeme123"},
+        )
+        test_username = f"sessiontest_{uuid4().hex[:8]}"
+        integration_client.post(
+            "/api/v1/admin/users",
+            json={"username": test_username, "password": "password123"},
+        )
+
+        # Login as test user
+        integration_client.cookies.clear()
+        login_response = integration_client.post(
+            "/api/v1/auth/login",
+            json={"username": test_username, "password": "password123"},
+        )
+        assert login_response.status_code == 200
+
+        # Verify session works
+        me_response = integration_client.get("/api/v1/auth/me")
+        assert me_response.status_code == 200
+
+        # Change password
+        integration_client.post(
+            "/api/v1/auth/change-password",
+            json={"current_password": "password123", "new_password": "newpassword123"},
+        )
+
+        # Old session should be invalidated - try to access /me
+        # (note: the change-password call itself may have cleared the session cookie)
+        me_response2 = integration_client.get("/api/v1/auth/me")
+        # This should fail because all sessions were invalidated
+        assert me_response2.status_code == 401