# Extract TOTP/HOTP secret keys from Google Authenticator
[](https://github.com/scito/extract_otp_secret_keys/actions/workflows/ci.yml)
---
Extract two-factor authentication (2FA, TFA) secret keys from export QR codes of "Google Authenticator" app.
The secret and otp values can be printed and exported to json or csv. The QR codes can be printed or saved as PNG images.
## Usage
1. Export the QR codes from "Google Authenticator" app
2. Read QR codes with QR code reader
3. Save the captured QR codes in a text file. Save each QR code on a new line. (The captured QR codes look like `otpauth-migration://offline?data=...` )
4. Call this script with the file as input:
python extract_otp_secret_keys.py -p example_export.txt
## Dependencies
pip install -r requirements.txt
Known to work with
* Python 3.10.6, protobuf 4.21.5, qrcode 7.3.1, and pillow 9.2
For protobuf versions 3.14.0 or similar or Python 3.6, use the extract_otp_secret_keys version 1.4.0.
### Optional
For printing QR codes, the qrcode module is required, otherwise it can be omitted.
pip install qrcode[pil]
## Technical background
The export QR code of "Google Authenticator" contains the URL `otpauth-migration://offline?data=...` .
The data parameter is a base64 encoded proto3 message (Google Protocol Buffers).
Command for regeneration of Python code from proto3 message definition file (only necessary in case of changes of the proto3 message definition or new protobuf versions):
protoc --python_out=protobuf_generated_python google_auth.proto
The generated protobuf Python code was generated by protoc 21.5 (https://github.com/protocolbuffers/protobuf/releases/tag/v21.5).
## References
* Proto3 documentation: https://developers.google.com/protocol-buffers/docs/pythontutorial
* Template code: https://github.com/beemdevelopment/Aegis/pull/406
## Alternative installation methods
### pipenv
You can you use [Pipenv ](https://github.com/pypa/pipenv ) for running extract_otp_secret_keys.
```
pipenv install
pipenv shell
python extract_otp_secret_keys.py example_export.txt
```
### venv
Alternatively, you can use a python virtual env for the dependencies:
python -m venv venv
. venv/bin/activate
pip install -r requirements-buildenv.txt
pip install -r requirements.txt
The requirements\*.txt files contain all the dependencies (also the optional ones).
To leave the python virtual env just call `deactivate` .
### devbox
Install [devbox ](https://github.com/jetpack-io/devbox ), which is a wrapper for nix. Then enter the environment with Python and the packages installed with:
```
devbox shell
```
## Tests
### PyTest
There are basic [pytest ](https://pytest.org )s, see `test_extract_otp_secret_keys_pytest.py` .
Run tests:
```
pytest
```
or
```
python -m pytest
```
### unittest
There are basic [unittest ](https://docs.python.org/3.10/library/unittest.html )s, see `test_extract_otp_secret_keys_unittest.py` .
Run tests:
```
python -m unittest
```
