Two Factor Authentication Best Practices

import { betterAuth } from 'better-auth';
import { twoFactor } from 'better-auth/plugins';

export const auth = betterAuth({
	appName: 'My App',
	plugins: [
		twoFactor({
			issuer: 'My App'
		})
	]
});

import { createAuthClient } from 'better-auth/client';
import { twoFactorClient } from 'better-auth/client/plugins';

export const authClient = createAuthClient({
	plugins: [
		twoFactorClient({
			onTwoFactorRedirect() {
				window.location.href = '/2fa';
			}
		})
	]
});

const enable2FA = async (password: string) => {
	const { data, error } = await authClient.twoFactor.enable({
		password
	});

	if (data) {
		// data.totpURI — generate a QR code from this
		// data.backupCodes — display to user
	}
};

import QRCode from 'react-qr-code';

const TotpSetup = ({ totpURI }: { totpURI: string }) => {
	return <QRCode value={totpURI} />;
};

const verifyTotp = async (code: string) => {
	const { data, error } = await authClient.twoFactor.verifyTotp({
		code,
		trustDevice: true
	});
};

twoFactor({
	totpOptions: {
		digits: 6, // 6 or 8 digits (default: 6)
		period: 30 // Code validity period in seconds (default: 30)
	}
});

import { betterAuth } from 'better-auth';
import { twoFactor } from 'better-auth/plugins';
import { sendEmail } from './email';

export const auth = betterAuth({
	plugins: [
		twoFactor({
			otpOptions: {
				sendOTP: async ({ user, otp }, ctx) => {
					await sendEmail({
						to: user.email,
						subject: 'Your verification code',
						text: `Your code is: ${otp}`
					});
				},
				period: 5, // Code validity in minutes (default: 3)
				digits: 6, // Number of digits (default: 6)
				allowedAttempts: 5 // Max verification attempts (default: 5)
			}
		})
	]
});

twoFactor({
	otpOptions: {
		storeOTP: 'encrypted' // Options: "plain", "encrypted", "hashed"
	}
});

twoFactor({
	otpOptions: {
		storeOTP: {
			encrypt: async (token) => myEncrypt(token),
			decrypt: async (token) => myDecrypt(token)
		}
	}
});

const BackupCodes = ({ codes }: { codes: string[] }) => {
	return (
		<div>
			<p>Save these codes in a secure location:</p>
			<ul>
				{codes.map((code, i) => (
					<li key={i}>{code}</li>
				))}
			</ul>
		</div>
	);
};

const regenerateBackupCodes = async (password: string) => {
	const { data, error } = await authClient.twoFactor.generateBackupCodes({
		password
	});
	// data.backupCodes contains the new codes
};

const verifyBackupCode = async (code: string) => {
	const { data, error } = await authClient.twoFactor.verifyBackupCode({
		code,
		trustDevice: true
	});
};

twoFactor({
	backupCodeOptions: {
		amount: 10, // Number of codes to generate (default: 10)
		length: 10, // Length of each code (default: 10)
		storeBackupCodes: 'encrypted' // Options: "plain", "encrypted"
	}
});

const signIn = async (email: string, password: string) => {
	const { data, error } = await authClient.signIn.email(
		{ email, password },
		{
			onSuccess(context) {
				if (context.data.twoFactorRedirect) {
					window.location.href = '/2fa';
				}
			}
		}
	);
};

twoFactor({
	twoFactorCookieMaxAge: 600 // 10 minutes in seconds (default)
});

twoFactor({
	otpOptions: {
		allowedAttempts: 5 // Max attempts per OTP code (default: 5)
	}
});

const disable2FA = async (password: string) => {
	const { data, error } = await authClient.twoFactor.disable({
		password
	});
};

import { betterAuth } from 'better-auth';
import { twoFactor } from 'better-auth/plugins';
import { sendEmail } from './email';

export const auth = betterAuth({
	appName: 'My App',
	plugins: [
		twoFactor({
			// TOTP settings
			issuer: 'My App',
			totpOptions: {
				digits: 6,
				period: 30
			},
			// OTP settings
			otpOptions: {
				sendOTP: async ({ user, otp }) => {
					await sendEmail({
						to: user.email,
						subject: 'Your verification code',
						text: `Your code is: ${otp}`
					});
				},
				period: 5,
				allowedAttempts: 5,
				storeOTP: 'encrypted'
			},
			// Backup code settings
			backupCodeOptions: {
				amount: 10,
				length: 10,
				storeBackupCodes: 'encrypted'
			},
			// Session settings
			twoFactorCookieMaxAge: 600, // 10 minutes
			trustDeviceMaxAge: 30 * 24 * 60 * 60 // 30 days
		})
	]
});