Two factor authentication for Devise

Features

• control sms code pattern
• configure max login attempts
• per user level control if he really need two factor authentication
• your own sms logic

Configuration

Initial Setup

In a Rails environment, require the gem in your Gemfile:

gem 'two_factor_authentication'

Once that's done, run:

bundle install

Automatic installation

In order to add two factor authorisation to a model, run the command:

bundle exec rails g two_factor_authentication MODEL

Where MODEL is your model name (e.g. User or Admin). This generator will add :two_factor_authenticatable to your model and create a migration in db/migrate/, which will add :otp_secret_key and :second_factor_attempts_count to your table. Finally, run the migration with:

bundle exec rake db:migrate

Add the following line to your model to fully enable two-factor auth:

has_one_time_password

Set config values if desired for maximum second factor attempts count and allowed time drift for one-time passwords:

config.max_login_attempts = 3
config.allowed_otp_drift_seconds = 30

Override the method to send one-time passwords in your model, this is automatically called when a user logs in:

def send_two_factor_authentication_code
  # use Model#otp_code and send via SMS, etc.
end

Manual installation

To manually enable two factor authentication for the User model, you should add two_factor_authentication to your devise line, like:

devise :database_authenticatable, :registerable,
       :recoverable, :rememberable, :trackable, :validatable, :two_factor_authenticatable

Add the following line to your model to fully enable two-factor auth:

has_one_time_password

Set config values if desired for maximum second factor attempts count and allowed time drift for one-time passwords:

config.max_login_attempts = 3
config.allowed_otp_drift_seconds = 30

Override the method to send one-time passwords in your model, this is automatically called when a user logs in:

def send_two_factor_authentication_code
  # use Model#otp_code and send via SMS, etc.
end

Customisation and Usage

By default second factor authentication enabled for each user, you can change it with this method in your User model:

def need_two_factor_authentication?(request)
  request.ip != '127.0.0.1'
end

this will disable two factor authentication for local users

This gem is compatible with Google Authenticator (https://support.google.com/accounts/answer/1066447?hl=en). You can generate provisioning uris by invoking the following method on your model:

user.provisioning_uri #This assumes a user model with an email attributes

This provisioning uri can then be turned in to a QR code if desired so that users may add the app to Google Authenticator easily. Once this is done they may retrieve a one-time password directly from the Google Authenticator app as well as through whatever method you define in send_two_factor_authentication_code

Example

TwoFactorAuthenticationExample