Add TOTP-based two-factor authentication

- Add 2FA setup, enable, disable, and backup code management
- Integrate 2FA challenge flow into login process
- Add frontend modal for 2FA configuration
- Support backup codes for account recovery

frontend/src/api/backend/getToken.ts

@@ -1,9 +1,22 @@
 import * as api from "./base";
-import type { TokenResponse } from "./responseTypes";
+import type { TokenResponse, TwoFactorChallengeResponse } from "./responseTypes";
 
-export async function getToken(identity: string, secret: string): Promise<TokenResponse> {
+export type LoginResponse = TokenResponse | TwoFactorChallengeResponse;
+
+export function isTwoFactorChallenge(response: LoginResponse): response is TwoFactorChallengeResponse {
+	return "requires2fa" in response && response.requires2fa === true;
+}
+
+export async function getToken(identity: string, secret: string): Promise<LoginResponse> {
 	return await api.post({
 		url: "/tokens",
 		data: { identity, secret },
 	});
 }
+
+export async function verify2FA(challengeToken: string, code: string): Promise<TokenResponse> {
+	return await api.post({
+		url: "/tokens/2fa",
+		data: { challengeToken, code },
+	});
+}

frontend/src/api/backend/index.ts

@@ -60,3 +60,4 @@ export * from "./updateStream";
 export * from "./updateUser";
 export * from "./uploadCertificate";
 export * from "./validateCertificate";
+export * from "./twoFactor";

frontend/src/api/backend/responseTypes.ts

@@ -25,3 +25,22 @@ export interface VersionCheckResponse {
 	latest: string | null;
 	updateAvailable: boolean;
 }
+
+export interface TwoFactorChallengeResponse {
+	requires2fa: boolean;
+	challengeToken: string;
+}
+
+export interface TwoFactorStatusResponse {
+	enabled: boolean;
+	backupCodesRemaining: number;
+}
+
+export interface TwoFactorSetupResponse {
+	secret: string;
+	otpauthUrl: string;
+}
+
+export interface TwoFactorEnableResponse {
+	backupCodes: string[];
+}

frontend/src/api/backend/twoFactor.ts

@@ -0,0 +1,58 @@
+import { camelizeKeys, decamelizeKeys } from "humps";
+import AuthStore from "src/modules/AuthStore";
+import type {
+	TwoFactorEnableResponse,
+	TwoFactorSetupResponse,
+	TwoFactorStatusResponse,
+} from "./responseTypes";
+import * as api from "./base";
+
+export async function get2FAStatus(userId: number | "me"): Promise<TwoFactorStatusResponse> {
+	return await api.get({
+		url: `/users/${userId}/2fa`,
+	});
+}
+
+export async function start2FASetup(userId: number | "me"): Promise<TwoFactorSetupResponse> {
+	return await api.post({
+		url: `/users/${userId}/2fa/setup`,
+	});
+}
+
+export async function enable2FA(userId: number | "me", code: string): Promise<TwoFactorEnableResponse> {
+	return await api.put({
+		url: `/users/${userId}/2fa/enable`,
+		data: { code },
+	});
+}
+
+export async function disable2FA(userId: number | "me", code: string): Promise<{ success: boolean }> {
+	const headers: Record<string, string> = {
+		"Content-Type": "application/json",
+	};
+	if (AuthStore.token) {
+		headers.Authorization = `Bearer ${AuthStore.token.token}`;
+	}
+
+	const response = await fetch(`/api/users/${userId}/2fa`, {
+		method: "DELETE",
+		headers,
+		body: JSON.stringify(decamelizeKeys({ code })),
+	});
+
+	const payload = await response.json();
+	if (!response.ok) {
+		throw new Error(payload.error?.messageI18n || payload.error?.message || "Failed to disable 2FA");
+	}
+	return camelizeKeys(payload) as { success: boolean };
+}
+
+export async function regenerateBackupCodes(
+	userId: number | "me",
+	code: string,
+): Promise<TwoFactorEnableResponse> {
+	return await api.post({
+		url: `/users/${userId}/2fa/backup-codes`,
+		data: { code },
+	});
+}

frontend/src/components/SiteHeader.tsx

@@ -1,9 +1,9 @@
-import { IconLock, IconLogout, IconUser } from "@tabler/icons-react";
+import { IconLock, IconLogout, IconShieldLock, IconUser } from "@tabler/icons-react";
 import { LocalePicker, NavLink, ThemeSwitcher } from "src/components";
 import { useAuthState } from "src/context";
 import { useUser } from "src/hooks";
 import { T } from "src/locale";
-import { showChangePasswordModal, showUserModal } from "src/modals";
+import { showChangePasswordModal, showTwoFactorModal, showUserModal } from "src/modals";
 import styles from "./SiteHeader.module.css";
 
 export function SiteHeader() {
@@ -108,6 +108,17 @@ export function SiteHeader() {
 									<IconLock width={18} />
 									<T id="user.change-password" />
 								</a>
+								<a
+									href="?"
+									className="dropdown-item"
+									onClick={(e) => {
+										e.preventDefault();
+										showTwoFactorModal("me");
+									}}
+								>
+									<IconShieldLock width={18} />
+									<T id="user.two-factor" />
+								</a>
 								<div className="dropdown-divider" />
 								<a
 									href="?"

frontend/src/context/AuthContext.tsx

@@ -1,13 +1,28 @@
 import { useQueryClient } from "@tanstack/react-query";
 import { createContext, type ReactNode, useContext, useState } from "react";
 import { useIntervalWhen } from "rooks";
-import { getToken, loginAsUser, refreshToken, type TokenResponse } from "src/api/backend";
+import {
+	getToken,
+	isTwoFactorChallenge,
+	loginAsUser,
+	refreshToken,
+	verify2FA,
+	type TokenResponse,
+} from "src/api/backend";
 import AuthStore from "src/modules/AuthStore";
 
+// 2FA challenge state
+export interface TwoFactorChallenge {
+	challengeToken: string;
+}
+
 // Context
 export interface AuthContextType {
 	authenticated: boolean;
+	twoFactorChallenge: TwoFactorChallenge | null;
 	login: (username: string, password: string) => Promise<void>;
+	verifyTwoFactor: (code: string) => Promise<void>;
+	cancelTwoFactor: () => void;
 	loginAs: (id: number) => Promise<void>;
 	logout: () => void;
 	token?: string;
@@ -24,17 +39,35 @@ interface Props {
 function AuthProvider({ children, tokenRefreshInterval = 5 * 60 * 1000 }: Props) {
 	const queryClient = useQueryClient();
 	const [authenticated, setAuthenticated] = useState(AuthStore.hasActiveToken());
+	const [twoFactorChallenge, setTwoFactorChallenge] = useState<TwoFactorChallenge | null>(null);
 
 	const handleTokenUpdate = (response: TokenResponse) => {
 		AuthStore.set(response);
 		setAuthenticated(true);
+		setTwoFactorChallenge(null);
 	};
 
 	const login = async (identity: string, secret: string) => {
 		const response = await getToken(identity, secret);
+		if (isTwoFactorChallenge(response)) {
+			setTwoFactorChallenge({ challengeToken: response.challengeToken });
+			return;
+		}
 		handleTokenUpdate(response);
 	};
 
+	const verifyTwoFactor = async (code: string) => {
+		if (!twoFactorChallenge) {
+			throw new Error("No 2FA challenge pending");
+		}
+		const response = await verify2FA(twoFactorChallenge.challengeToken, code);
+		handleTokenUpdate(response);
+	};
+
+	const cancelTwoFactor = () => {
+		setTwoFactorChallenge(null);
+	};
+
 	const loginAs = async (id: number) => {
 		const response = await loginAsUser(id);
 		AuthStore.add(response);
@@ -69,7 +102,15 @@ function AuthProvider({ children, tokenRefreshInterval = 5 * 60 * 1000 }: Props)
 		true,
 	);
 
-	const value = { authenticated, login, logout, loginAs };
+	const value = {
+		authenticated,
+		twoFactorChallenge,
+		login,
+		verifyTwoFactor,
+		cancelTwoFactor,
+		loginAs,
+		logout,
+	};
 
 	return <AuthContext.Provider value={value}>{children}</AuthContext.Provider>;
 }

frontend/src/locale/src/en.json

@@ -1,4 +1,61 @@
 {
+	"2fa.backup-codes-remaining": {
+		"defaultMessage": "Backup codes remaining: {count}"
+	},
+	"2fa.backup-warning": {
+		"defaultMessage": "Save these backup codes in a secure place. Each code can only be used once."
+	},
+	"2fa.disable": {
+		"defaultMessage": "Disable Two-Factor Authentication"
+	},
+	"2fa.disable-confirm": {
+		"defaultMessage": "Disable 2FA"
+	},
+	"2fa.disable-warning": {
+		"defaultMessage": "Disabling two-factor authentication will make your account less secure."
+	},
+	"2fa.disabled": {
+		"defaultMessage": "Disabled"
+	},
+	"2fa.done": {
+		"defaultMessage": "I have saved my backup codes"
+	},
+	"2fa.enable": {
+		"defaultMessage": "Enable Two-Factor Authentication"
+	},
+	"2fa.enabled": {
+		"defaultMessage": "Enabled"
+	},
+	"2fa.enter-code": {
+		"defaultMessage": "Enter verification code"
+	},
+	"2fa.enter-code-disable": {
+		"defaultMessage": "Enter verification code to disable"
+	},
+	"2fa.regenerate": {
+		"defaultMessage": "Regenerate"
+	},
+	"2fa.regenerate-backup": {
+		"defaultMessage": "Regenerate Backup Codes"
+	},
+	"2fa.regenerate-instructions": {
+		"defaultMessage": "Enter a verification code to generate new backup codes. Your old codes will be invalidated."
+	},
+	"2fa.secret-key": {
+		"defaultMessage": "Secret Key"
+	},
+	"2fa.setup-instructions": {
+		"defaultMessage": "Scan this QR code with your authenticator app, or enter the secret manually."
+	},
+	"2fa.status": {
+		"defaultMessage": "Status"
+	},
+	"2fa.title": {
+		"defaultMessage": "Two-Factor Authentication"
+	},
+	"2fa.verify-enable": {
+		"defaultMessage": "Verify and Enable"
+	},
 	"access-list": {
 		"defaultMessage": "Access List"
 	},
@@ -386,6 +443,21 @@
 	"loading": {
 		"defaultMessage": "Loading…"
 	},
+	"login.2fa-code": {
+		"defaultMessage": "Verification Code"
+	},
+	"login.2fa-code-placeholder": {
+		"defaultMessage": "Enter code"
+	},
+	"login.2fa-description": {
+		"defaultMessage": "Enter the code from your authenticator app"
+	},
+	"login.2fa-title": {
+		"defaultMessage": "Two-Factor Authentication"
+	},
+	"login.2fa-verify": {
+		"defaultMessage": "Verify"
+	},
 	"login.title": {
 		"defaultMessage": "Login to your account"
 	},
@@ -674,6 +746,9 @@
 	"user.switch-light": {
 		"defaultMessage": "Switch to Light mode"
 	},
+	"user.two-factor": {
+		"defaultMessage": "Two-Factor Auth"
+	},
 	"username": {
 		"defaultMessage": "Username"
 	},

frontend/src/modals/TwoFactorModal.tsx

@@ -0,0 +1,368 @@
+import EasyModal, { type InnerModalProps } from "ez-modal-react";
+import { Field, Form, Formik } from "formik";
+import { type ReactNode, useCallback, useEffect, useState } from "react";
+import { Alert } from "react-bootstrap";
+import Modal from "react-bootstrap/Modal";
+import {
+	disable2FA,
+	enable2FA,
+	get2FAStatus,
+	regenerateBackupCodes,
+	start2FASetup,
+} from "src/api/backend";
+import { Button } from "src/components";
+import { T } from "src/locale";
+import { validateString } from "src/modules/Validations";
+
+type Step = "loading" | "status" | "setup" | "verify" | "backup" | "disable";
+
+const showTwoFactorModal = (id: number | "me") => {
+	EasyModal.show(TwoFactorModal, { id });
+};
+
+interface Props extends InnerModalProps {
+	id: number | "me";
+}
+
+const TwoFactorModal = EasyModal.create(({ id, visible, remove }: Props) => {
+	const [error, setError] = useState<ReactNode | null>(null);
+	const [step, setStep] = useState<Step>("loading");
+	const [isEnabled, setIsEnabled] = useState(false);
+	const [backupCodesRemaining, setBackupCodesRemaining] = useState(0);
+	const [setupData, setSetupData] = useState<{ secret: string; otpauthUrl: string } | null>(null);
+	const [backupCodes, setBackupCodes] = useState<string[]>([]);
+	const [isSubmitting, setIsSubmitting] = useState(false);
+
+	const loadStatus = useCallback(async () => {
+		try {
+			const status = await get2FAStatus(id);
+			setIsEnabled(status.enabled);
+			setBackupCodesRemaining(status.backupCodesRemaining);
+			setStep("status");
+		} catch (err: any) {
+			setError(err.message || "Failed to load 2FA status");
+			setStep("status");
+		}
+	}, [id]);
+
+	useEffect(() => {
+		loadStatus();
+	}, [loadStatus]);
+
+	const handleStartSetup = async () => {
+		setError(null);
+		setIsSubmitting(true);
+		try {
+			const data = await start2FASetup(id);
+			setSetupData(data);
+			setStep("setup");
+		} catch (err: any) {
+			setError(err.message || "Failed to start 2FA setup");
+		}
+		setIsSubmitting(false);
+	};
+
+	const handleVerify = async (values: { code: string }) => {
+		setError(null);
+		setIsSubmitting(true);
+		try {
+			const result = await enable2FA(id, values.code);
+			setBackupCodes(result.backupCodes);
+			setStep("backup");
+		} catch (err: any) {
+			setError(err.message || "Failed to enable 2FA");
+		}
+		setIsSubmitting(false);
+	};
+
+	const handleDisable = async (values: { code: string }) => {
+		setError(null);
+		setIsSubmitting(true);
+		try {
+			await disable2FA(id, values.code);
+			setIsEnabled(false);
+			setStep("status");
+		} catch (err: any) {
+			setError(err.message || "Failed to disable 2FA");
+		}
+		setIsSubmitting(false);
+	};
+
+	const handleRegenerateBackup = async (values: { code: string }) => {
+		setError(null);
+		setIsSubmitting(true);
+		try {
+			const result = await regenerateBackupCodes(id, values.code);
+			setBackupCodes(result.backupCodes);
+			setStep("backup");
+		} catch (err: any) {
+			setError(err.message || "Failed to regenerate backup codes");
+		}
+		setIsSubmitting(false);
+	};
+
+	const handleBackupDone = () => {
+		setIsEnabled(true);
+		setBackupCodes([]);
+		loadStatus();
+	};
+
+	const renderContent = () => {
+		if (step === "loading") {
+			return (
+				<div className="text-center py-4">
+					<div className="spinner-border" role="status">
+						<span className="visually-hidden">Loading...</span>
+					</div>
+				</div>
+			);
+		}
+
+		if (step === "status") {
+			return (
+				<div className="py-2">
+					<div className="mb-4">
+						<div className="d-flex align-items-center justify-content-between mb-2">
+							<span className="fw-bold">
+								<T id="2fa.status" />
+							</span>
+							<span className={`badge text-white ${isEnabled ? "bg-success" : "bg-secondary"}`}>
+								{isEnabled ? <T id="2fa.enabled" /> : <T id="2fa.disabled" />}
+							</span>
+						</div>
+						{isEnabled && (
+							<p className="text-muted small mb-0">
+								<T id="2fa.backup-codes-remaining" data={{ count: backupCodesRemaining }} />
+							</p>
+						)}
+					</div>
+					{!isEnabled ? (
+						<Button
+							fullWidth
+							color="azure"
+							onClick={handleStartSetup}
+							isLoading={isSubmitting}
+						>
+							<T id="2fa.enable" />
+						</Button>
+					) : (
+						<div className="d-flex flex-column gap-2">
+							<Button fullWidth onClick={() => setStep("disable")}>
+								<T id="2fa.disable" />
+							</Button>
+							<Button fullWidth onClick={() => setStep("verify")}>
+								<T id="2fa.regenerate-backup" />
+							</Button>
+						</div>
+					)}
+				</div>
+			);
+		}
+
+		if (step === "setup" && setupData) {
+			return (
+				<div className="py-2">
+					<p className="text-muted mb-3">
+						<T id="2fa.setup-instructions" />
+					</p>
+					<div className="text-center mb-3">
+						<img
+							src={`https://api.qrserver.com/v1/create-qr-code/?size=200x200&data=${encodeURIComponent(setupData.otpauthUrl)}`}
+							alt="QR Code"
+							className="img-fluid"
+							style={{ maxWidth: "200px" }}
+						/>
+					</div>
+					<label className="mb-3 d-block">
+						<span className="form-label small text-muted">
+							<T id="2fa.secret-key" />
+						</span>
+						<input
+							type="text"
+							className="form-control font-monospace"
+							value={setupData.secret}
+							readOnly
+							onClick={(e) => (e.target as HTMLInputElement).select()}
+						/>
+					</label>
+					<Formik initialValues={{ code: "" }} onSubmit={handleVerify}>
+						{() => (
+							<Form>
+								<Field name="code" validate={validateString(6, 6)}>
+									{({ field, form }: any) => (
+										<label className="mb-3 d-block">
+											<span className="form-label">
+												<T id="2fa.enter-code" />
+											</span>
+											<input
+												{...field}
+												type="text"
+												inputMode="numeric"
+												autoComplete="one-time-code"
+												className={`form-control ${form.errors.code && form.touched.code ? "is-invalid" : ""}`}
+												placeholder="000000"
+												maxLength={6}
+											/>
+											<div className="invalid-feedback">{form.errors.code}</div>
+										</label>
+									)}
+								</Field>
+								<div className="d-flex gap-2">
+									<Button
+										type="button"
+										fullWidth
+										onClick={() => setStep("status")}
+										disabled={isSubmitting}
+									>
+										<T id="cancel" />
+									</Button>
+									<Button type="submit" fullWidth color="azure" isLoading={isSubmitting}>
+										<T id="2fa.verify-enable" />
+									</Button>
+								</div>
+							</Form>
+						)}
+					</Formik>
+				</div>
+			);
+		}
+
+		if (step === "backup") {
+			return (
+				<div className="py-2">
+					<Alert variant="warning">
+						<T id="2fa.backup-warning" />
+					</Alert>
+					<div className="mb-3">
+						<div className="row g-2">
+							{backupCodes.map((code, index) => (
+								<div key={index} className="col-6">
+									<code className="d-block p-2 bg-light rounded text-center">{code}</code>
+								</div>
+							))}
+						</div>
+					</div>
+					<Button fullWidth color="azure" onClick={handleBackupDone}>
+						<T id="2fa.done" />
+					</Button>
+				</div>
+			);
+		}
+
+		if (step === "disable") {
+			return (
+				<div className="py-2">
+					<Alert variant="warning">
+						<T id="2fa.disable-warning" />
+					</Alert>
+					<Formik initialValues={{ code: "" }} onSubmit={handleDisable}>
+						{() => (
+							<Form>
+								<Field name="code" validate={validateString(6, 6)}>
+									{({ field, form }: any) => (
+										<label className="mb-3 d-block">
+											<span className="form-label">
+												<T id="2fa.enter-code-disable" />
+											</span>
+											<input
+												{...field}
+												type="text"
+												inputMode="numeric"
+												autoComplete="one-time-code"
+												className={`form-control ${form.errors.code && form.touched.code ? "is-invalid" : ""}`}
+												placeholder="000000"
+												maxLength={6}
+											/>
+											<div className="invalid-feedback">{form.errors.code}</div>
+										</label>
+									)}
+								</Field>
+								<div className="d-flex gap-2">
+									<Button
+										type="button"
+										fullWidth
+										onClick={() => setStep("status")}
+										disabled={isSubmitting}
+									>
+										<T id="cancel" />
+									</Button>
+									<Button type="submit" fullWidth color="red" isLoading={isSubmitting}>
+										<T id="2fa.disable-confirm" />
+									</Button>
+								</div>
+							</Form>
+						)}
+					</Formik>
+				</div>
+			);
+		}
+
+		if (step === "verify") {
+			return (
+				<div className="py-2">
+					<p className="text-muted mb-3">
+						<T id="2fa.regenerate-instructions" />
+					</p>
+					<Formik initialValues={{ code: "" }} onSubmit={handleRegenerateBackup}>
+						{() => (
+							<Form>
+								<Field name="code" validate={validateString(6, 6)}>
+									{({ field, form }: any) => (
+										<label className="mb-3 d-block">
+											<span className="form-label">
+												<T id="2fa.enter-code" />
+											</span>
+											<input
+												{...field}
+												type="text"
+												inputMode="numeric"
+												autoComplete="one-time-code"
+												className={`form-control ${form.errors.code && form.touched.code ? "is-invalid" : ""}`}
+												placeholder="000000"
+												maxLength={6}
+											/>
+											<div className="invalid-feedback">{form.errors.code}</div>
+										</label>
+									)}
+								</Field>
+								<div className="d-flex gap-2">
+									<Button
+										type="button"
+										fullWidth
+										onClick={() => setStep("status")}
+										disabled={isSubmitting}
+									>
+										<T id="cancel" />
+									</Button>
+									<Button type="submit" fullWidth color="azure" isLoading={isSubmitting}>
+										<T id="2fa.regenerate" />
+									</Button>
+								</div>
+							</Form>
+						)}
+					</Formik>
+				</div>
+			);
+		}
+
+		return null;
+	};
+
+	return (
+		<Modal show={visible} onHide={remove}>
+			<Modal.Header closeButton>
+				<Modal.Title>
+					<T id="2fa.title" />
+				</Modal.Title>
+			</Modal.Header>
+			<Modal.Body>
+				<Alert variant="danger" show={!!error} onClose={() => setError(null)} dismissible>
+					{error}
+				</Alert>
+				{renderContent()}
+			</Modal.Body>
+		</Modal>
+	);
+});
+
+export { showTwoFactorModal };

frontend/src/modals/index.ts

@@ -13,4 +13,5 @@ export * from "./RedirectionHostModal";
 export * from "./RenewCertificateModal";
 export * from "./SetPasswordModal";
 export * from "./StreamModal";
+export * from "./TwoFactorModal";
 export * from "./UserModal";

frontend/src/pages/Login/index.tsx

@@ -8,8 +8,77 @@ import { intl, T } from "src/locale";
 import { validateEmail, validateString } from "src/modules/Validations";
 import styles from "./index.module.css";
 
-export default function Login() {
-	const emailRef = useRef(null);
+function TwoFactorForm() {
+	const codeRef = useRef<HTMLInputElement>(null);
+	const [formErr, setFormErr] = useState("");
+	const { verifyTwoFactor, cancelTwoFactor } = useAuthState();
+
+	const onSubmit = async (values: any, { setSubmitting }: any) => {
+		setFormErr("");
+		try {
+			await verifyTwoFactor(values.code);
+		} catch (err) {
+			if (err instanceof Error) {
+				setFormErr(err.message);
+			}
+		}
+		setSubmitting(false);
+	};
+
+	useEffect(() => {
+		codeRef.current?.focus();
+	}, []);
+
+	return (
+		<>
+			<h2 className="h2 text-center mb-4">
+				<T id="login.2fa-title" />
+			</h2>
+			<p className="text-secondary text-center mb-4">
+				<T id="login.2fa-description" />
+			</p>
+			{formErr !== "" && <Alert variant="danger">{formErr}</Alert>}
+			<Formik initialValues={{ code: "" }} onSubmit={onSubmit}>
+				{({ isSubmitting }) => (
+					<Form>
+						<div className="mb-3">
+							<Field name="code" validate={validateString(6, 20)}>
+								{({ field, form }: any) => (
+									<label className="form-label">
+										<T id="login.2fa-code" />
+										<input
+											{...field}
+											ref={codeRef}
+											type="text"
+											inputMode="numeric"
+											autoComplete="one-time-code"
+											required
+											maxLength={20}
+											className={`form-control ${form.errors.code && form.touched.code ? "is-invalid" : ""}`}
+											placeholder={intl.formatMessage({ id: "login.2fa-code-placeholder" })}
+										/>
+										<div className="invalid-feedback">{form.errors.code}</div>
+									</label>
+								)}
+							</Field>
+						</div>
+						<div className="form-footer d-flex gap-2">
+							<Button type="button" fullWidth onClick={cancelTwoFactor} disabled={isSubmitting}>
+								<T id="cancel" />
+							</Button>
+							<Button type="submit" fullWidth color="azure" isLoading={isSubmitting}>
+								<T id="login.2fa-verify" />
+							</Button>
+						</div>
+					</Form>
+				)}
+			</Formik>
+		</>
+	);
+}
+
+function LoginForm() {
+	const emailRef = useRef<HTMLInputElement>(null);
 	const [formErr, setFormErr] = useState("");
 	const { login } = useAuthState();
 
@@ -26,10 +95,79 @@ export default function Login() {
 	};
 
 	useEffect(() => {
-		// @ts-expect-error ts-migrate(2531) FIXME: Object is possibly 'null'.
-		emailRef.current.focus();
+		emailRef.current?.focus();
 	}, []);
 
+	return (
+		<>
+			<h2 className="h2 text-center mb-4">
+				<T id="login.title" />
+			</h2>
+			{formErr !== "" && <Alert variant="danger">{formErr}</Alert>}
+			<Formik
+				initialValues={
+					{
+						email: "",
+						password: "",
+					} as any
+				}
+				onSubmit={onSubmit}
+			>
+				{({ isSubmitting }) => (
+					<Form>
+						<div className="mb-3">
+							<Field name="email" validate={validateEmail()}>
+								{({ field, form }: any) => (
+									<label className="form-label">
+										<T id="email-address" />
+										<input
+											{...field}
+											ref={emailRef}
+											type="email"
+											required
+											className={`form-control ${form.errors.email && form.touched.email ? " is-invalid" : ""}`}
+											placeholder={intl.formatMessage({ id: "email-address" })}
+										/>
+										<div className="invalid-feedback">{form.errors.email}</div>
+									</label>
+								)}
+							</Field>
+						</div>
+						<div className="mb-2">
+							<Field name="password" validate={validateString(8, 255)}>
+								{({ field, form }: any) => (
+									<>
+										<label className="form-label">
+											<T id="password" />
+											<input
+												{...field}
+												type="password"
+												autoComplete="current-password"
+												required
+												maxLength={255}
+												className={`form-control ${form.errors.password && form.touched.password ? " is-invalid" : ""}`}
+												placeholder={intl.formatMessage({ id: "password" })}
+											/>
+											<div className="invalid-feedback">{form.errors.password}</div>
+										</label>
+									</>
+								)}
+							</Field>
+						</div>
+						<div className="form-footer">
+							<Button type="submit" fullWidth color="azure" isLoading={isSubmitting}>
+								<T id="sign-in" />
+							</Button>
+						</div>
+					</Form>
+				)}
+			</Formik>
+		</>
+	);
+}
+
+export default function Login() {
+	const { twoFactorChallenge } = useAuthState();
 	const health = useHealth();
 
 	const getVersion = () => {
@@ -56,68 +194,7 @@ export default function Login() {
 				</div>
 				<div className="card card-md">
 					<div className="card-body">
-						<h2 className="h2 text-center mb-4">
-							<T id="login.title" />
-						</h2>
-						{formErr !== "" && <Alert variant="danger">{formErr}</Alert>}
-						<Formik
-							initialValues={
-								{
-									email: "",
-									password: "",
-								} as any
-							}
-							onSubmit={onSubmit}
-						>
-							{({ isSubmitting }) => (
-								<Form>
-									<div className="mb-3">
-										<Field name="email" validate={validateEmail()}>
-											{({ field, form }: any) => (
-												<label className="form-label">
-													<T id="email-address" />
-													<input
-														{...field}
-														ref={emailRef}
-														type="email"
-														required
-														className={`form-control ${form.errors.email && form.touched.email ? " is-invalid" : ""}`}
-														placeholder={intl.formatMessage({ id: "email-address" })}
-													/>
-													<div className="invalid-feedback">{form.errors.email}</div>
-												</label>
-											)}
-										</Field>
-									</div>
-									<div className="mb-2">
-										<Field name="password" validate={validateString(8, 255)}>
-											{({ field, form }: any) => (
-												<>
-													<label className="form-label">
-														<T id="password" />
-														<input
-															{...field}
-															type="password"
-															autoComplete="current-password"
-															required
-															maxLength={255}
-															className={`form-control ${form.errors.password && form.touched.password ? " is-invalid" : ""}`}
-															placeholder={intl.formatMessage({ id: "password" })}
-														/>
-														<div className="invalid-feedback">{form.errors.password}</div>
-													</label>
-												</>
-											)}
-										</Field>
-									</div>
-									<div className="form-footer">
-										<Button type="submit" fullWidth color="azure" isLoading={isSubmitting}>
-											<T id="sign-in" />
-										</Button>
-									</div>
-								</Form>
-							)}
-						</Formik>
+						{twoFactorChallenge ? <TwoFactorForm /> : <LoginForm />}
 					</div>
 				</div>
 				<div className="text-center text-secondary mt-3">{getVersion()}</div>