authentik/passbook/factors/view.py

198 lines
8.1 KiB
Python

"""passbook multi-factor authentication engine"""
from typing import List, Tuple
from django.contrib.auth import login
from django.contrib.auth.mixins import UserPassesTestMixin
from django.shortcuts import get_object_or_404, redirect, reverse
from django.utils.http import urlencode
from django.views.generic import View
from structlog import get_logger
from passbook.core.models import Factor, User
from passbook.core.views.utils import PermissionDeniedView
from passbook.lib.utils.reflection import class_to_path, path_to_class
from passbook.lib.utils.urls import is_url_absolute
from passbook.policies.engine import PolicyEngine
LOGGER = get_logger()
# Argument used to redirect user after login
NEXT_ARG_NAME = "next"
def _redirect_with_qs(view, get_query_set=None):
"""Wrapper to redirect whilst keeping GET Parameters"""
target = reverse(view)
if get_query_set:
target += "?" + urlencode(get_query_set.items())
return redirect(target)
class AuthenticationView(UserPassesTestMixin, View):
"""Wizard-like Multi-factor authenticator"""
SESSION_FACTOR = "passbook_factor"
SESSION_PENDING_FACTORS = "passbook_pending_factors"
SESSION_PENDING_USER = "passbook_pending_user"
SESSION_USER_BACKEND = "passbook_user_backend"
SESSION_IS_SSO_LOGIN = "passbook_sso_login"
pending_user: User
pending_factors: List[Tuple[str, str]] = []
_current_factor_class: Factor
current_factor: Factor
# Allow only not authenticated users to login
def test_func(self):
return AuthenticationView.SESSION_PENDING_USER in self.request.session
def handle_no_permission(self):
# Function from UserPassesTestMixin
if NEXT_ARG_NAME in self.request.GET:
return redirect(self.request.GET.get(NEXT_ARG_NAME))
if self.request.user.is_authenticated:
return _redirect_with_qs("passbook_core:overview", self.request.GET)
return _redirect_with_qs("passbook_core:auth-login", self.request.GET)
def get_pending_factors(self):
"""Loading pending factors from Database or load from session variable"""
# Write pending factors to session
if AuthenticationView.SESSION_PENDING_FACTORS in self.request.session:
return self.request.session[AuthenticationView.SESSION_PENDING_FACTORS]
# Get an initial list of factors which are currently enabled
# and apply to the current user. We check policies here and block the request
_all_factors = (
Factor.objects.filter(enabled=True).order_by("order").select_subclasses()
)
pending_factors = []
for factor in _all_factors:
LOGGER.debug(
"Checking if factor applies to user",
factor=factor,
user=self.pending_user,
)
policy_engine = PolicyEngine(
factor.policies.all(), self.pending_user, self.request
)
policy_engine.build()
if policy_engine.passing:
pending_factors.append((factor.uuid.hex, factor.type))
LOGGER.debug("Factor applies", factor=factor, user=self.pending_user)
return pending_factors
def dispatch(self, request, *args, **kwargs):
# Check if user passes test (i.e. SESSION_PENDING_USER is set)
user_test_result = self.get_test_func()()
if not user_test_result:
return self.handle_no_permission()
# Extract pending user from session (only remember uid)
self.pending_user = get_object_or_404(
User, id=self.request.session[AuthenticationView.SESSION_PENDING_USER]
)
self.pending_factors = self.get_pending_factors()
# Read and instantiate factor from session
factor_uuid, factor_class = None, None
if AuthenticationView.SESSION_FACTOR not in request.session:
# Case when no factors apply to user, return error denied
if not self.pending_factors:
# Case when user logged in from SSO provider and no more factors apply
if AuthenticationView.SESSION_IS_SSO_LOGIN in request.session:
LOGGER.debug("User authenticated with SSO, logging in...")
return self._user_passed()
return self.user_invalid()
factor_uuid, factor_class = self.pending_factors[0]
else:
factor_uuid, factor_class = request.session[
AuthenticationView.SESSION_FACTOR
]
# Lookup current factor object
self.current_factor = (
Factor.objects.filter(uuid=factor_uuid).select_subclasses().first()
)
# Instantiate Next Factor and pass request
factor = path_to_class(factor_class)
self._current_factor_class = factor(self)
self._current_factor_class.pending_user = self.pending_user
self._current_factor_class.request = request
return super().dispatch(request, *args, **kwargs)
def get(self, request, *args, **kwargs):
"""pass get request to current factor"""
LOGGER.debug(
"Passing GET",
view_class=class_to_path(self._current_factor_class.__class__),
)
return self._current_factor_class.get(request, *args, **kwargs)
def post(self, request, *args, **kwargs):
"""pass post request to current factor"""
LOGGER.debug(
"Passing POST",
view_class=class_to_path(self._current_factor_class.__class__),
)
return self._current_factor_class.post(request, *args, **kwargs)
def user_ok(self):
"""Redirect to next Factor"""
LOGGER.debug(
"Factor passed",
factor_class=class_to_path(self._current_factor_class.__class__),
)
# Remove passed factor from pending factors
current_factor_tuple = (
self.current_factor.uuid.hex,
class_to_path(self._current_factor_class.__class__),
)
if current_factor_tuple in self.pending_factors:
self.pending_factors.remove(current_factor_tuple)
next_factor = None
if self.pending_factors:
next_factor = self.pending_factors.pop()
# Save updated pening_factor list to session
self.request.session[
AuthenticationView.SESSION_PENDING_FACTORS
] = self.pending_factors
self.request.session[AuthenticationView.SESSION_FACTOR] = next_factor
LOGGER.debug("Rendering Factor", next_factor=next_factor)
return _redirect_with_qs("passbook_core:auth-process", self.request.GET)
# User passed all factors
LOGGER.debug("User passed all factors, logging in", user=self.pending_user)
return self._user_passed()
def user_invalid(self):
"""Show error message, user cannot login.
This should only be shown if user authenticated successfully, but is disabled/locked/etc"""
LOGGER.debug("User invalid")
self.cleanup()
return _redirect_with_qs("passbook_core:auth-denied", self.request.GET)
def _user_passed(self):
"""User Successfully passed all factors"""
backend = self.request.session[AuthenticationView.SESSION_USER_BACKEND]
login(self.request, self.pending_user, backend=backend)
LOGGER.debug("Logged in", user=self.pending_user)
# Cleanup
self.cleanup()
next_param = self.request.GET.get(NEXT_ARG_NAME, None)
if next_param and not is_url_absolute(next_param):
return redirect(next_param)
return _redirect_with_qs("passbook_core:overview")
def cleanup(self):
"""Remove temporary data from session"""
session_keys = [
self.SESSION_FACTOR,
self.SESSION_PENDING_FACTORS,
self.SESSION_PENDING_USER,
self.SESSION_USER_BACKEND,
]
for key in session_keys:
if key in self.request.session:
del self.request.session[key]
LOGGER.debug("Cleaned up sessions")
class FactorPermissionDeniedView(PermissionDeniedView):
"""User could not be authenticated"""