otplib API Documentation / @otplib/hotp / HOTP

Class: HOTP

Defined in: hotp/src/class.ts:46

HOTP class for HMAC-based one-time password generation

Example

import { HOTP } from '@otplib/hotp';
import { NodeCryptoPlugin } from '@otplib/plugin-crypto-node';
import { ScureBase32Plugin } from '@otplib/plugin-base32-scure';

const hotp = new HOTP({
  issuer: 'MyApp',
  label: 'user@example.com',
  counter: 0,
  crypto: new NodeCryptoPlugin(),
  base32: new ScureBase32Plugin(),
});

const secret = hotp.generateSecret();
const token = await hotp.generate(0);
const isValid = await hotp.verify({ token, counter: 0 });

Constructors

Constructor

new HOTP(options?): HOTP

Defined in: hotp/src/class.ts:50

Parameters

options?

HOTPOptions = {}

Returns

HOTP

Methods

generate()

generate(counter, options?): Promise<string>

Defined in: hotp/src/class.ts:78

Generate an HOTP code for a specific counter

Parameters

counter

number

The counter value

options?

Partial<HOTPOptions>

Optional overrides

Returns

Promise<string>

The HOTP code

Throws

If the algorithm is invalid or unsupported by the plugin

Throws

If HMAC computation fails in the crypto plugin

---

generateSecret()

generateSecret(): string

Defined in: hotp/src/class.ts:60

Generate a random Base32-encoded secret

Returns

string

Base32-encoded secret

---

toURI()

toURI(counter?): string

Defined in: hotp/src/class.ts:150

Generate an otpauth:// URI for QR codes

Parameters

counter?

number = 0

The counter value

Returns

string

The otpauth:// URI

Throws

If a non-empty algorithm is not supported

---

verify()

verify(params, options?): Promise<VerifyResult>

Defined in: hotp/src/class.ts:109

Verify an HOTP code

Parameters

params

Verification parameters

counter

number

token

string

options?

Partial<HOTPOptions & object>

Optional verification options

Returns

Promise<VerifyResult>

Verification result with validity and optional delta

Throws

If the algorithm is invalid or unsupported by the plugin

Throws

If HMAC computation fails in the crypto plugin