Script to backup Google Authenticator secrets as QR-codes

backup-google-authenticator.py

#!/usr/bin/env python3
# Copyright 2014 Matteo Bertini [email protected]
# Released as Public Domain
#
# Latest version:
#  wget http://slug.it/backup-google-authenticator.py
#
# Requirements
# ============
#
# A rooted phone and a google authenticator full of secrets,
# connected with an USB cable to a computer with:
# - python3
# - adb (Android SDK)
# - qrencode
# - ImageMagick (+ ghostview for the labels if using brew)
#
# Usage
# =====
#
# Connect the phone, run, save or print or acquire the codes.

import os
import sys
import shutil
import sqlite3
import subprocess
import tempfile
import urllib.parse
import uu
import hashlib
import time

def get_databases(dest):
    with open(dest, "w+b") as db:
        cmd = "adb shell \"su -c 'uuencode /data/data/com.google.android.apps.authenticator2/databases/databases -'\""
        dump = subprocess.Popen(cmd, stdout=subprocess.PIPE, shell=True)
        uu.decode(dump.stdout, db)
    return dest

def get_accounts(db):
    conn = sqlite3.connect(db)
    cursor = conn.cursor()
    for email, secret in cursor.execute("SELECT email, secret FROM accounts"):
        yield (email, secret)

def create_qrcode(msg, filename):
    subprocess.check_call(["qrencode", "-s", "4", "-o", filename, msg])
    return filename

def set_image_comment(image, comment):
    subprocess.check_call(["mogrify", "-comment", comment, image])
    return image

def create_contact_sheet(filename):
    subprocess.check_call(["montage", "-geometry", "150x150+50+50", "-tile", "1x", "-label", r"%c", "*.png", filename])
    return filename

def backup_google_authenticator_secrets(dest_dir, dest_filename):
    orig_dir = os.getcwd()
    temp_dir = tempfile.mkdtemp()
    os.chdir(temp_dir)

    for account, secret in get_accounts(get_databases("databases.sqlite")):
        account_ = urllib.parse.quote_plus(account)
        qrsecret = "otpauth://totp/{account_}?secret={secret}".format(**locals())
        filename = hashlib.md5(account.encode('utf-8')).hexdigest()+".png"
        create_qrcode(qrsecret, filename)
        set_image_comment(filename, account)

    shutil.copyfile(os.path.join(temp_dir, create_contact_sheet(dest_filename)),
                    os.path.join(dest_dir, dest_filename))
    shutil.rmtree(temp_dir)

def checked_dir(adir):
    if os.path.isdir(adir):
        return adir
    else:
        raise argparse.ArgumentTypeError("Invalid dir %r" % adir)

if __name__ == "__main__":
    import argparse
    parser = argparse.ArgumentParser("Backup Google Authenticator secrets to QR-codes")
    parser.add_argument("dest", metavar="DIR", nargs="?", type=checked_dir,
                        help="Save the final image 'auth-codes.png' in %(default)s", default='.')
    args = parser.parse_args()
    backup_google_authenticator_secrets(args.dest, "auth-codes.png")