React Native Touch ID

React Native Touch ID is a React Native library for authenticating users with biometric authentication methods like Face ID and Touch ID on both iOS and Android (experimental).

Note: the awesome folks over at Expo have begun open-sourcing some of their modules for compatability with React Native projects not built with Expo. As such you can attempt to use their equivalent library called LocalAuthentication at expo-local-authentication if you run into any issues here!

react-native-touch-id

Breaking changes

Please review all changes in the Changelog

Documentation

Install

npm i --save react-native-touch-id

yarn add react-native-touch-id

Support

Due to the rapid changes being made in the React Native ecosystem, we are not officially going to support this module on anything but the latest version of React Native. The current supported version is indicated on the React Native badge at the top of this README. If it's out of date, we encourage you to submit a pull request!

Usage

Linking the Library

In order to use Biometric Authentication, you must first link the library to your project.

Using react-native link

Use the built-in command:

react-native link react-native-touch-id

Using Cocoapods (iOS only)

On iOS you can also link package by updating your podfile

pod 'TouchID', :path => "#{node_modules_path}/react-native-touch-id"

and then run

pod install

Using native linking

There's excellent documentation on how to do this in the React Native Docs.

Platform Differences

iOS and Android differ slightly in their TouchID authentication.

On Android you can customize the title and color of the pop-up by passing in the optional config object with a color and title key to the authenticate method. Even if you pass in the config object, iOS does not allow you change the color nor the title of the pop-up. iOS does support passcodeFallback as an option, which when set to true will allow users to use their device pin - useful for people with Face / Touch ID disabled. Passcode fallback only happens if the device does not have touch id or face id enabled. Android allows running the authentication in background mode without the pop-up. When the background mode is active, use TouchId.onError to catch authentication errors.

Error handling is also different between the platforms, with iOS currently providing much more descriptive error codes.

App Permissions

Add the following permissions to their respective files:

In your AndroidManifest.xml:

<uses-permission android:name="android.permission.USE_FINGERPRINT" />

In your Info.plist:

<key>NSFaceIDUsageDescription</key>
<string>Enabling Face ID allows you quick and secure access to your account.</string>

Requesting Face ID/Touch ID Authentication

Once you've linked the library, you'll want to make it available to your app by requiring it:

var TouchID = require('react-native-touch-id');

import TouchID from 'react-native-touch-id';

Requesting Face ID/Touch ID Authentication is as simple as calling:

TouchID.authenticate('to demo this react-native component', optionalConfigObject)
  .then(success => {
    // Success code
  })
  .catch(error => {
    // Failure code
  });

Example

Using Face ID/Touch ID in your app will usually look like this:

import React from "react"
var TouchID = require('react-native-touch-id');
//or import TouchID from 'react-native-touch-id'
 
class YourComponent extends React.Component {
  _pressHandler() {
    TouchID.authenticate('to demo this react-native component', optionalConfigObject)
      .then(success => {
        AlertIOS.alert('Authenticated Successfully');
      })
      .catch(error => {
        AlertIOS.alert('Authentication Failed');
      });
  },
 
  render() {
    return (
      <View>
        ...
        <TouchableHighlight onPress={this._pressHandler}>
          <Text>
            Authenticate with Touch ID
          </Text>
        </TouchableHighlight>
      </View>
    );
  }
};

Methods

authenticate(reason, config)

Attempts to authenticate with Face ID/Touch ID. Returns a Promise object.

Arguments

reason - optional - String that provides a clear reason for requesting authentication.
config - optional - configuration object for more detailed dialog setup:
- title - Android - title of confirmation dialog
- imageColor - Android - color of fingerprint image
- imageErrorColor - Android - color of fingerprint image after failed attempt
- sensorDescription - Android - text shown next to the fingerprint image
- sensorErrorDescription - Android - text shown next to the fingerprint image after failed attempt
- cancelText - Android - cancel button text
- backgroundMode - Android - by default set to false. If set to true popup will not show
- fallbackLabel - iOS - by default specified 'Show Password' label. If set to empty string label is invisible.
- unifiedErrors - return unified error messages (see below) (default = false)
- passcodeFallback - iOS - by default set to false. If set to true, will allow use of keypad passcode.

Examples

const optionalConfigObject = {
  title: "Authentication Required", // Android
  imageColor: "#e00606", // Android
  imageErrorColor: "#ff0000", // Android
  sensorDescription: "Touch sensor", // Android
  sensorErrorDescription: "Failed", // Android
  cancelText: "Cancel", // Android
  backgroundMode: false, // Android
  fallbackLabel: "Show Passcode", // iOS (if empty, then label is hidden)
  unifiedErrors: false, // use unified error messages (default false)
  passcodeFallback: false, // iOS - allows the device to fall back to using the passcode, if faceid/touch is not available. this does not mean that if touchid/faceid fails the first few times it will revert to passcode, rather that if the former are not enrolled, then it will use the passcode.
};
 
TouchID.authenticate('to demo this react-native component', optionalConfigObject)
  .then(success => {
    AlertIOS.alert('Authenticated Successfully');
  })
  .catch(error => {
    AlertIOS.alert('Authentication Failed');
  });
 
//Catch the error messages in background mode, which are otherwise displayed in the modal
TouchID.onAuthError(error => {
       Alert.alert('Authentication Error');
    });

onAuthError() - Android only

Returns an EventEmitter listener which can be cancelled with the method remove()

cancelBackgroundAuthentication() - Android only

Cancel the current authentication which was run with the config backgroundMode: true

isSupported()

Returns a Promise that rejects if TouchID is not supported. On iOS resolves with a biometryType String of FaceID or TouchID.

Examples

const optionalConfigObject = {
  unifiedErrors: false // use unified error messages (default false)
  passcodeFallback: false // if true is passed, itwill allow isSupported to return an error if the device is not enrolled in touch id/face id etc. Otherwise, it will just tell you what method is supported, even if the user is not enrolled.  (default false)
}
 
TouchID.isSupported(optionalConfigObject)
  .then(biometryType => {
    // Success code
    if (biometryType === 'FaceID') {
        console.log('FaceID is supported.');
    } else {
        console.log('TouchID is supported.');
    }
  })
  .catch(error => {
    // Failure code
    console.log(error);
  });

Errors

There are various reasons why biomentric authentication may not be available or fail. TouchID.isSupported and TouchID.authenticate will return an error representing the reason.

iOS Errors

Format:

{
  name: "TheErrorCode",
  message: "the error message",
  details: {
    name: "TheErrorCode",
    message: "the error message"
  }
}

name	message
`LAErrorAuthenticationFailed`	Authentication was not successful because the user failed to provide valid credentials.
`LAErrorUserCancel`	Authentication was canceled by the user—for example, the user tapped Cancel in the dialog.
`LAErrorUserFallback`	Authentication was canceled because the user tapped the fallback button (Enter Password).
`LAErrorSystemCancel`	Authentication was canceled by system—for example, if another application came to foreground while the authentication dialog was up.
`LAErrorPasscodeNotSet`	Authentication could not start because the passcode is not set on the device.
`LAErrorTouchIDNotAvailable`	Authentication could not start because Touch ID is not available on the device
`LAErrorTouchIDNotEnrolled`	Authentication could not start because Touch ID has no enrolled fingers.
`LAErrorTouchIDLockout`	Authentication failed because of too many failed attempts.
`RCTTouchIDUnknownError`	Could not authenticate for an unknown reason.
`RCTTouchIDNotSupported`	Device does not support Touch ID.

More information on errors can be found in Apple's Documentation.

Android errors

Format:

{
  name: "Touch ID Error",
  message: "Touch ID Error",
  details: "the error message",
  code: "THE_ERROR_CODE"
}

isSupported:

name	message	details	code
`Touch ID Error`	`Touch ID Error`	Not supported.	`NOT_SUPPORTED`
`Touch ID Error`	`Touch ID Error`	Not supported.	`NOT_AVAILABLE`
`Touch ID Error`	`Touch ID Error`	Not supported.	`NOT_PRESENT`
`Touch ID Error`	`Touch ID Error`	Not supported.	`NOT_ENROLLED`

authenticate:

name	message	details	code
`Touch ID Error`	`Touch ID Error`	Not supported	`NOT_SUPPORTED`
`Touch ID Error`	`Touch ID Error`	Not supported	`NOT_AVAILABLE`
`Touch ID Error`	`Touch ID Error`	Not supported	`NOT_PRESENT`
`Touch ID Error`	`Touch ID Error`	Not supported	`NOT_ENROLLED`
`Touch ID Error`	`Touch ID Error`	failed	`AUTHENTICATION_FAILED`
`Touch ID Error`	`Touch ID Error`	cancelled	`AUTHENTICATION_CANCELED`
`Touch ID Error`	`Touch ID Error`	Too many attempts. Try again Later.	`FINGERPRINT_ERROR_LOCKOUT`
`Touch ID Error`	`Touch ID Error`	Too many attempts. Fingerprint sensor disabled.	`FINGERPRINT_ERROR_LOCKOUT_PERMANENT`
`Touch ID Error`	`Touch ID Error`	?	`FINGERPRINT_ERROR_UNABLE_TO_PROCESS`,
`Touch ID Error`	`Touch ID Error`	?	`FINGERPRINT_ERROR_TIMEOUT`,
`Touch ID Error`	`Touch ID Error`	?	`FINGERPRINT_ERROR_CANCELED`,
`Touch ID Error`	`Touch ID Error`	?	`FINGERPRINT_ERROR_VENDOR`,

Unified errors

Format:

{
  name: "TouchIDError",
  message: "the error message",
  code: "THE_ERROR_CODE"
}

name	message	code
`TouchIDError`	Authentication failed	`AUTHENTICATION_FAILED`
`TouchIDError`	User canceled authentication	`USER_CANCELED`
`TouchIDError`	System canceled authentication	`SYSTEM_CANCELED`
`TouchIDError`	Biometry hardware not present	`NOT_PRESENT`
`TouchIDError`	Biometry is not supported	`NOT_SUPPORTED`
`TouchIDError`	Biometry is not currently available	`NOT_AVAILABLE`
`TouchIDError`	Biometry is not enrolled	`NOT_ENROLLED`
`TouchIDError`	Biometry timeout	`TIMEOUT`
`TouchIDError`	Biometry lockout	`LOCKOUT`
`TouchIDError`	Biometry permanent lockout	`LOCKOUT_PERMANENT`
`TouchIDError`	Biometry processing error	`PROCESSING_ERROR`
`TouchIDError`	User selected fallback	`USER_FALLBACK`
`TouchIDError`	User selected fallback not enrolled	`FALLBACK_NOT_ENROLLED`
`TouchIDError`	Unknown error	`UNKNOWN_ERROR`

License

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.