⛔️ WORK IN PROGRESS - not yet released

Djoser passwordless

A Passwordless login add-on for Djoser (Django Rest Framework authentication). Built with djoser, django-sms and django-phonenumber-field

🔑 Before you start!

Please consider your risk and threat landscape before adopting this library.

Authentication is always a trade-off of usability and security. This library has been built to give you the power to adjust those trade-offs as much as possible, and made an attempt to give you a reasonable set of defaults, but it's up to you to make those decisions. Please consider the following risks bellow

Installation

pip install djoser_passwordless

settings.py

INSTALLED_APPS = (
    ...
    "djoser",
    "djoser_passwordless",
    ...
)
...
DJOSER_PASSWORDLESS = {
    "ALLOWED_PASSWORDLESS_METHODS": ["EMAIL", "MOBILE"]
}

Remember to set the settings for django-sms and django-phonenumber-field if you are using mobile token requests

urlpatterns = (
    ...
    re_path(r"^passwordless/", include("djoser_passwordless.urls")),
    ...
)

🕵️ Risks

Brute force

Although token requests are throttled by default, and token lifetime is limited, if you know a user email/phone it is possible to continuously request tokens (the default throttle is 1 minute), and try to brute force that token during the token lifetime (10 minutes).

Mitigations

• Set INCORRECT_SHORT_TOKEN_REDEEMS_TOKEN to True, so that any attempts at redeeming a token from an account will count as a user (MAX_TOKEN_USES is default set to 1) - Tradeoff is that if a user is being a victim of brute force attack, they will not be able to login with passwordless tokens, since it's likely the attacker will exhaust the token uses with failed attempts

• Set DECORATORS.token_redeem_rate_limit_decorator or DECORATORS.token_request_rate_limit_decorator with your choice of request throttling library. - Tradeoff is that if there is an attacker hitting your service, you might prevent any user from logging in because someone is hitting this endpoint, so beware how you implement it. Note that because request limiting usually requires a key value db like redis, it is explicitly left out of this project to reduce it's dependencies and configuration needs.

Features

• International phone number validation and standardization (expects db phone numbers to be in same format)
• Basic throttling
• Configurable tokens
• Short (for SMS) and long tokens for magic links
• Configurable serializers, permissions and decorators.

URLs and Examples:

Available URLS

• request/email/
• request/mobile
• exchange/standalone/
• exchange/email/
• exchange/mobile/

Requesting a token

curl --request POST \
  --url http://localhost:8000/passwordless/request/email/ \
  --data '{
	"email": "sergioisidoro@example.com"
}'

Response

{
	"detail": "A token has been sent to you"
}

Exchanging a one time token for a auth token

curl --request POST \
  --url http://localhost:8000/passwordless/exchange/ \
  --data '{
	"email": "sergioisidoro@example.com"
	"token": "902488"
}'

{
	"auth_token": "3b8e6a2aed0435f95495e728b0fb41d0367a872d"
}

Config

Basic configuration

• ALLOWED_PASSWORDLESS_METHODS (default=["email"]) - Which methods can be used to request a token? (Valid - ["email", "mobile"])
• EMAIL_FIELD_NAME (default="email") - Name of the user field that holds the email info
• MOBILE_FIELD_NAME (default="phone_number") - Name of the user field that holds phone number info
• SHORT_TOKEN_LENGTH (default=6) - The length of the short tokens
• LONG_TOKEN_LENGTH (default=64) - The length of the tokens that can redeemed standalone (without the original request data)
• SHORT_TOKEN_CHARS (default="0123456789") - The characters to be used when generating the short token
• LONG_TOKEN_CHARS (default="abcdefghijklmnopqrstuvwxyz0123456789") - Tokens used to generate the long token
• TOKEN_LIFETIME (default=600) - Number of seconds the token is valid
• MAX_TOKEN_USES (default=1) - How many times a token can be used - This can be adjusted because some email clients try to follow links, and might accidentally use tokens.
• TOKEN_REQUEST_THROTTLE_SECONDS - (default=60) - How many seconds to wait before allowing a new token to be issued for a particular user
• ALLOW_ADMIN_AUTHENTICATION (default=False) - Allow admin users to login without password (checks is_admin and is_staff from Django AbstractUser)
• REGISTER_NONEXISTENT_USERS (default=False) - Register users who do not have an account and request a passwordless login token? - Will generate a random username which is configurable (See. conf.py)
• REGISTRATION_SETS_UNUSABLE_PASSWORD (Default=True) - When unusable password is set, users cannot reset passwords via the normal Django flows. This means users registered via passwordless cannot login through password.
• INCORRECT_SHORT_TOKEN_REDEEMS_TOKEN (default=False) - Should incorrect short token auth attempts count to the uses of a token? When set to true, together with MAX_TOKEN_USES to 1, this means a token has only one shot at being used.
• PASSWORDLESS_EMAIL_LOGIN_URL (default=None) - URL template for the link redeeming the standalone link: eg my-app://page/{token}

Credits

This package was created with Cookiecutter_ and the audreyr/cookiecutter-pypackage_ project template.

• Aaronn's django-rest-framework-passwordless project https://github.com/aaronn/django-rest-framework-passwordless
• Sunscrapers' Djoser project - https://github.com/sunscrapers/djoser
• Cookiecutter: https://github.com/audreyr/cookiecutter
• audreyr/cookiecutter-pypackage: https://github.com/audreyr/cookiecutter-pypackage

License

• Free software: MIT license
• Do no harm