bid_main/templates/bid_main/mfa/setup.html

@@ -40,6 +40,7 @@ Multi-factor Authentication Setup
   <button>Configure a new TOTP device</button>
 </div>
 
+{% if user_can_setup_recovery %}
 <div class="bid box mt-3">
   <h3>Recovery codes</h3>
   <p>
@@ -47,17 +48,34 @@ Multi-factor Authentication Setup
     Each code can be used only once.
     You can generate a new set of recovery codes at any time, any remaining old codes will become invalidated.
   </p>
-  {% with devices=devices_per_category.recovery %}
-  {% for d in devices %}
+  {% with recovery=devices_per_category.recovery.0 %}
+  {% if recovery %}
   <div class="mb-3">
-    {% with code_count=d.token_set.count %}
+    {% with code_count=recovery.token_set.count %}
     {{ code_count }} recovery code{{ code_count|pluralize }} remaining
-    <button>Download</button>
-    <button class="btn-danger">Invalidate</button>
+    {% if recovery_codes %}
+    <a href="?display_recovery_codes=" class="btn">Hide</a>
+    {% else %}
+    <a href="?display_recovery_codes=1" class="btn">Display</a>
+    {% endif %}
+    <form action="{% url 'bid_main:invalidate_recovery_mfa' %}" method="post" class="d-inline-flex">{% csrf_token %}
+      <button class="btn-danger" type="submit">Invalidate</button>
+    </form>
+    {# populated on display_recovery_codes=1 #}
+    {% if recovery_codes %}
+    <ul>
+      {% for code in recovery_codes %}
+      <li>{{ code }}</li>
+      {% endfor %}
+    </ul>
+    {% endif %}
     {% endwith %}
   </div>
-  {% endfor %}
-  <button>{% if devices %}Regenerate{% else %}Generate{% endif %} recovery codes</button>
+  {% endif %}
+  <form action="{% url 'bid_main:generate_recovery_mfa' %}" method="post">{% csrf_token %}
+    <button type="submit">{% if recovery %}Regenerate{% else %}Generate{% endif %} recovery codes</button>
+  </form>
   {% endwith %}
 </div>
+{% endif %}
 {% endblock %}

bid_main/urls.py

@@ -156,6 +156,16 @@ urlpatterns = [
         mfa.DisableMfaView.as_view(),
         name='disable_mfa',
     ),
+    path(
+        'mfa/generate-recovery/',
+        mfa.GenerateRecoveryMfaView.as_view(),
+        name='generate_recovery_mfa',
+    ),
+    path(
+        'mfa/invalidate-recovery/',
+        mfa.InvalidateRecoveryMfaView.as_view(),
+        name='invalidate_recovery_mfa',
+    ),
 ]
 
 # Only enable this on a dev server:

bid_main/views/mfa.py

@@ -1,12 +1,15 @@
-
 from collections import defaultdict
+from os import urandom
 
 from django_otp import devices_for_user
 from django_otp.plugins.otp_static.models import StaticDevice
 from django_otp.plugins.otp_totp.models import TOTPDevice
 from django.db import transaction
-from django.urls import reverse_lazy
+from django.http import HttpResponseBadRequest
+from django.shortcuts import redirect
+from django.urls import reverse, reverse_lazy
 from django.views.generic import TemplateView
+from django.views.generic.base import View
 from django.views.generic.edit import FormView
 
 from . import mixins
@@ -14,18 +17,31 @@ from bid_main.forms import DisableMfaForm
 
 
 class MfaView(mixins.MfaRequiredIfConfiguredMixin, TemplateView):
+    """Don't allow to setup recovery codes unless the user has already configured some other method.
+
+    Otherwise MfaRequiredIfConfiguredMixin locks the user out immediately, not giving a chance
+    to copy the recovery codes.
+    """
     template_name = "bid_main/mfa/setup.html"
 
     def get_context_data(self, **kwargs):
-        devices = list(devices_for_user(self.request.user))
+        user = self.request.user
+        devices = list(devices_for_user(user))
         devices_per_category = defaultdict(list)
+        recovery_codes = []
+        user_can_setup_recovery = False
         for device in devices:
             if isinstance(device, StaticDevice):
                 devices_per_category['recovery'].append(device)
+                if self.request.GET.get('display_recovery_codes', None):
+                    recovery_codes = [t.token for t in device.token_set.all()]
             if isinstance(device, TOTPDevice):
                 devices_per_category['totp'].append(device)
+                user_can_setup_recovery = True
         return {
             'devices_per_category': devices_per_category,
+            'recovery_codes': recovery_codes,
+            'user_can_setup_recovery': user_can_setup_recovery,
             'user_has_mfa_configured': len(devices) > 0,
         }
 
@@ -35,8 +51,29 @@ class DisableMfaView(mixins.MfaRequiredMixin, FormView):
     template_name = "bid_main/mfa/disable.html"
     success_url = reverse_lazy('bid_main:mfa')
 
+    @transaction.atomic
     def form_valid(self, form):
-        with transaction.atomic():
-            for device in devices_for_user(self.request.user, confirmed=None):
-                device.delete()
+        for device in devices_for_user(self.request.user, confirmed=None):
+            device.delete()
         return super().form_valid(form)
+
+
+class GenerateRecoveryMfaView(mixins.MfaRequiredIfConfiguredMixin, View):
+    @transaction.atomic
+    def post(self, request, *args, **kwargs):
+        user = self.request.user
+        if not list(filter(lambda d: not isinstance(d, StaticDevice), devices_for_user(user))):
+            # Forbid setting up recovery codes unless the user already has some other method
+            return HttpResponseBadRequest("can't setup recovery codes before other methods")
+        user.staticdevice_set.all().delete()
+        device = StaticDevice.objects.create(name='recovery', user=user)
+        for _ in range(10):
+            device.token_set.create(token=urandom(8).hex().upper())
+        return redirect(reverse('bid_main:mfa') + '?display_recovery_codes=1')
+
+
+class InvalidateRecoveryMfaView(mixins.MfaRequiredIfConfiguredMixin, View):
+    def post(self, request, *args, **kwargs):
+        user = self.request.user
+        user.staticdevice_set.all().delete()
+        return redirect('bid_main:mfa')