flows: add SESSION_KEY_APPLICATION_PRE

whenever a user tries to access an application without being authenticated to passbook, we now show notice which application they are going to continue to.

passbook/flows/views.py

@@ -29,6 +29,7 @@ LOGGER = get_logger()
 # Argument used to redirect user after login
 NEXT_ARG_NAME = "next"
 SESSION_KEY_PLAN = "passbook_flows_plan"
+SESSION_KEY_APPLICATION_PRE = "passbook_flows_application_pre"
 SESSION_KEY_GET = "passbook_flows_get"
 
 
@@ -198,8 +199,14 @@ class FlowExecutorView(View):
 
     def cancel(self):
         """Cancel current execution and return a redirect"""
-        if SESSION_KEY_PLAN in self.request.session:
-            del self.request.session[SESSION_KEY_PLAN]
+        keys_to_delete = [
+            SESSION_KEY_APPLICATION_PRE,
+            SESSION_KEY_PLAN,
+            SESSION_KEY_GET,
+        ]
+        for key in keys_to_delete:
+            if key in self.request.session:
+                del self.request.session[key]
 
 
 class FlowPermissionDeniedView(PermissionDeniedView):

passbook/policies/mixins.py

@@ -3,12 +3,14 @@ from typing import Optional
 
 from django.contrib import messages
 from django.contrib.auth.mixins import AccessMixin
+from django.contrib.auth.views import redirect_to_login
 from django.http import HttpRequest, HttpResponse
 from django.shortcuts import redirect
 from django.utils.translation import gettext as _
 from structlog import get_logger
 
 from passbook.core.models import Application, Provider, User
+from passbook.flows.views import SESSION_KEY_APPLICATION_PRE
 from passbook.policies.engine import PolicyEngine
 from passbook.policies.types import PolicyResult
 
@@ -25,6 +27,15 @@ class PolicyAccessMixin(BaseMixin, AccessMixin):
     """Mixin class for usage in Authorization views.
     Provider functions to check application access, etc"""
 
+    def handle_no_permission(self, application: Optional[Application] = None):
+        if application:
+            self.request.session[SESSION_KEY_APPLICATION_PRE] = application
+        return redirect_to_login(
+            self.request.get_full_path(),
+            self.get_login_url(),
+            self.get_redirect_field_name(),
+        )
+
     def handle_no_permission_authorized(self) -> HttpResponse:
         """Function called when user has no permissions but is authorized"""
         # TODO: Remove this URL and render the view instead

passbook/providers/oauth/views/oauth2.py

@@ -49,6 +49,10 @@ class AuthorizationFlowInitView(PolicyAccessMixin, LoginRequiredMixin, View):
             application = self.provider_to_application(provider)
         except Application.DoesNotExist:
             return self.handle_no_permission_authorized()
+        # Check if user is unauthenticated, so we pass the application
+        # for the identification stage
+        if not request.user.is_authenticated:
+            return self.handle_no_permission(application)
         # Check permissions
         result = self.user_has_access(application)
         if not result.passing:

passbook/providers/oidc/views.py

@@ -42,6 +42,10 @@ class AuthorizationFlowInitView(PolicyAccessMixin, LoginRequiredMixin, View):
             application = self.provider_to_application(provider)
         except Application.DoesNotExist:
             return self.handle_no_permission_authorized()
+        # Check if user is unauthenticated, so we pass the application
+        # for the identification stage
+        if not request.user.is_authenticated:
+            return self.handle_no_permission(application)
         # Check permissions
         result = self.user_has_access(application)
         if not result.passing:

passbook/providers/saml/views.py

@@ -47,7 +47,7 @@ REQUEST_KEY_RELAY_STATE = "RelayState"
 SESSION_KEY_AUTH_N_REQUEST = "authn_request"
 
 
-class SAMLSSOView(LoginRequiredMixin, PolicyAccessMixin, View):
+class SAMLSSOView(PolicyAccessMixin, LoginRequiredMixin, View):
     """"SAML SSO Base View, which plans a flow and injects our final stage.
     Calls get/post handler."""
 
@@ -62,7 +62,7 @@ class SAMLSSOView(LoginRequiredMixin, PolicyAccessMixin, View):
             SAMLProvider, pk=self.application.provider_id
         )
         if not request.user.is_authenticated:
-            return self.handle_no_permission()
+            return self.handle_no_permission(self.application)
         if not self.user_has_access(self.application).passing:
             return self.handle_no_permission_authorized()
         # Call the method handler, which checks the SAML Request

passbook/stages/identification/stage.py

@@ -12,6 +12,7 @@ from structlog import get_logger
 from passbook.core.models import Source, User
 from passbook.flows.planner import PLAN_CONTEXT_PENDING_USER
 from passbook.flows.stage import StageView
+from passbook.flows.views import SESSION_KEY_APPLICATION_PRE
 from passbook.stages.identification.forms import IdentificationForm
 from passbook.stages.identification.models import IdentificationStage
 
@@ -34,6 +35,12 @@ class IdentificationStageView(FormView, StageView):
 
     def get_context_data(self, **kwargs):
         current_stage: IdentificationStage = self.executor.current_stage
+        # If the user has been redirected to us whilst trying to access an
+        # application, SESSION_KEY_APPLICATION_PRE is set in the session
+        if SESSION_KEY_APPLICATION_PRE in self.request.session:
+            kwargs["application_pre"] = self.request.session[
+                SESSION_KEY_APPLICATION_PRE
+            ]
         # Check for related enrollment and recovery flow, add URL to view
         if current_stage.enrollment_flow:
             kwargs["enroll_url"] = reverse(

passbook/stages/identification/templates/stages/identification/login.html

@@ -11,6 +11,13 @@
 <div class="pf-c-login__main-body">
     <form method="POST" class="pf-c-form">
         {% block above_form %}
+            {% if application_pre %}
+            <p>
+                {% blocktrans with app_name=application_pre.name %}
+                Login to continue to <strong>{{ app_name }}</strong>.
+                {% endblocktrans %}
+            </p>
+            {% endif %}
         {% endblock %}
 
         {% include 'partials/form.html' %}