simple TOTP token generator w/ qrcode image decoding

totp-token.py

#!/usr/bin/env python3

# deps: zbar-tools, oathtool
#
# call it as toptp-token.py <qrimage-filename>
#
# 1. decodes the qrcode image via zbar-img
# 2. parses totp url and extracts parameters (secret, stepping, algo, ...)
# 3. calls oathtool to generate the current token
import subprocess
import sys

from urllib.parse import urlparse
from urllib.parse import parse_qs


if len(sys.argv) < 2:
    print("missing param")
    sys.exit(1)

url = subprocess.check_output(['zbarimg', '-q', '--nodbus', sys.argv[1]]).decode('utf8')

# print("URL: "+url)

parsed_url = urlparse(url)
parsed_qs = parse_qs(parsed_url.query)

if 'secret' not in parsed_qs:
    print("no secret")
    exit(1)

secret = parsed_qs['secret'][0]

cmd = cmd = ['oathtool', '-b', secret ]

if 'algorithm' in parsed_qs:
    cmd.append('--totp='+parsed_qs['algorithm'][0].strip())
else:
    cmd.append('--totp')

if 'digits' in parsed_qs:
    cmd.append('--digits='+parsed_qs['digits'][0].strip())

if 'period' in parsed_qs:
    cmd.append('--time-step-size='+parsed_qs['period'][0].strip())

# print(cmd)

code = subprocess.check_output(cmd).decode('utf8').strip()

print(code)

I am now almost required to use 2fa to login into GH. How this script works?

Just call it with a photo of the QR code: it will print out the decoded token.

By the way, if you've got an android device, I'd recomment FreeOTP.

We don't need 2FA on GitHub!

Agreed. But unfortunately, they won't listen to us. Typical for these Redmond boys.