MultiFactorAuth

A ruby library for generating one time passwords and QR Codes.

Installation

Add this line to your application's Gemfile:

gem 'multi_factor_auth'

And then execute:

$ bundle

Or install it yourself as:

$ gem install multi_factor_auth

Usage

Time based OTP's

totp = MultiFactorAuth::TOTP.new("base32secret3232", issuer: "My Service")
totp.now # => "492039"

# OTP verified for current time
totp.verify("492039") # => true
sleep 30
totp.verify("492039") # => false
totp.provisioning_uri("alice@google.com")

Counter based OTP's

hotp = MultiFactorAuth::HOTP.new("base32secretkey3232")
hotp.at(0) # => "260182"
hotp.at(1) # => "055283"
hotp.at(1401) # => "316439"

# OTP verified with a counter
hotp.verify("316439", 1401) # => true
hotp.verify("316439", 1402) # => false

Generating a Base32 Secret key

MultiFactorAuth::Base32.random_base32  # returns a 16 character base32 secret. Compatible with Google Authenticator

Generating a QR Code

totp = MultiFactorAuth::TOTP.new("base32secretkey3232")
qrcode = totp.qr_code("alice@google.com")
image = qrcode.as_png
svg = qrcode.as_svg
html = qrcode.as_html
string = qrcode.as_ansi
string = qrcode.to_s

Resources

• QR Codes
• Base32 Library
• The Ruby One Time Password Library

Contributing

• Fork the project
• Send a pull request

License

Open source under the terms of the MIT License.