A Python library for generating one time passwords according to RFC 4226 and the HOTP RFC , ported from Mark Percival's ROTP .
This is compatible with Google Authenticator apps available for Android and iPhone, and now in use on GMail
- OTP's involve a shared secret, stored both on the phone and the server
- OTP's can be generated on a phone without internet connectivity(AT&T mode)
- OTP's should always be used as a second factor of authentication(if your phone is lost, you account is still secured with a password)
- Google Authenticator allows you to store multiple OTP secrets and provision those using a QR Code(no more typing in the secret)
pip install pyotp
totp = pyotp.TOTP('base32secret3232')
totp.now() # => 492039
# OTP verified for current time
totp.verify(492039) # => True
time.sleep(30)
totp.verify(492039) # => False
hotp = pyotp.HOTP('base32secret3232')
hotp.at(0) # => 260182
hotp.at(1) # => 55283
hotp.at(1401) # => 316439
# OTP verified with a counter
hotp.verify(316439, 1401) # => True
hotp.verify(316439, 1402) # => False
pyotp.random_base32() # returns a 16 character base32 secret. Compatible with Google Authenticator
The library works with the Google Authenticator iPhone and Android app, and also includes the ability to generate provisioning URI's for use with the QR Code scanner built into the app.
totp.provisioning_uri("[email protected]") # => 'otpauth://totp/[email protected]?secret=JBSWY3DPEHPK3PXP'
hotp.provisioning_uri("[email protected]", 0) # => 'otpauth://hotp/[email protected]?secret=JBSWY3DPEHPK3PXP&counter=0'
This can then be rendered as a QR Code which can then be scanned and added to the users list of OTP credentials.
Scan the following barcode with your phone, using Google Authenticator
Now run the following and compare the output
import pyotp
totp = pyotp.TOTP("JBSWY3DPEHPK3PXP")
print "Current OTP: %s" % totp.now()
####1.3.0
- Ported to Python
Original Ruby version of ROTP by Mark Percival - ROTP PHP port of ROTP by Le Lag - OTPHP