Question form: Do not store invalid False values for required boolean questions (Z#23239887) (#6366)

* Fix customer views using wrong csrf middleware

This lead to persistent csrf validation errors if the token from the cookie expired, which could only be solved by clearing cookies.

* Remove unneccesary csrf_protect decorators

* Fix typo

Co-authored-by: Raphael Michel <michel@pretix.eu>

---------

Co-authored-by: Raphael Michel <michel@pretix.eu>

pyproject.toml

@@ -43,7 +43,7 @@ dependencies = [
   "django-countries==8.2.*",
   "django-filter==25.1",
   "django-formset-js-improved==0.5.0.5",
-  "django-formtools==2.6.1",
+  "django-formtools==2.7",
   "django-hierarkey==2.0.*,>=2.0.1",
   "django-hijack==3.7.*",
   "django-i18nfield==1.11.*",

src/pretix/base/forms/questions.py

@@ -1116,6 +1116,13 @@ class BaseQuestionsForm(forms.Form):
             if q.dependency_question_id and not question_is_visible(q.dependency_question_id, q.dependency_values) and answer is not None:
                 d['question_%d' % q.pk] = None
 
+        # Strip False answers to required yes/no questions even if all_optional is set, as our data model assumes that
+        # required yes/no questions can only be answered with yes
+        for q in question_cache.values():
+            if q.required and q.type == Question.TYPE_BOOLEAN:
+                if 'question_%d' % q.pk in d and d['question_%d' % q.pk] is False:
+                    del d['question_%d' % q.pk]
+
         return d
 
 

src/pretix/base/models/event.py

@@ -1403,15 +1403,12 @@ class Event(EventMixin, LoggedModel):
 
         for mp in self.organizer.meta_properties.all():
             if mp.required and not self.meta_data.get(mp.name):
-                issues.append(
-                    ('<a {a_attr}>' + gettext('You need to fill the meta parameter "{property}".') + '</a>').format(
-                        property=mp.name,
-                        a_attr='href="%s#id_prop-%d-value"' % (
-                            reverse('control:event.settings', kwargs={'organizer': self.organizer.slug, 'event': self.slug}),
-                            mp.pk
-                        )
-                    )
-                )
+                issues.append(format_html(
+                    '<a href="{href}{href_hash}">{text}</a>',
+                    text=gettext('You need to fill the meta parameter "{property}".').format(property=mp.name),
+                    href=reverse('control:event.settings', kwargs={'organizer': self.organizer.slug, 'event': self.slug}),
+                    href_hash=f'#id_prop-{mp.pk}-value',
+                ))
 
         responses = event_live_issues.send(self)
         for receiver, response in sorted(responses, key=lambda r: str(r[0])):

src/pretix/base/payment.py

@@ -1706,6 +1706,58 @@ class GiftCardPayment(BasePaymentProvider):
         )
 
 
+class BaseHistoricalPaymentProvider(BasePaymentProvider):
+    """
+    Base class for payment providers that no longer exist but can't be deleted to make sure historical
+    payments are shown correctly.
+
+    Subclasses are recommended to only implement:
+        - identifier
+        - verbose_name
+        - public_name
+    - payment_control_render
+    - payment_control_render_short
+    - refund_control_render
+    - refund_control_render_short
+    - render_invoice_text
+    - render_invoice_stamp
+    - api_payment_details
+    - api_refund_details
+    - shred_payment_info
+    - matching_id
+    - refund_matching_id
+    """
+
+    @property
+    def is_enabled(self) -> bool:
+        return False
+
+    @property
+    def settings_form_fields(self) -> dict:
+        return {}
+
+    def is_allowed(self, request: HttpRequest, total: Decimal=None) -> bool:
+        return False
+
+    def payment_is_valid_session(self, request: HttpRequest, payment: OrderPayment):
+        return False
+
+    def order_change_allowed(self, order: Order, request: HttpRequest=None) -> bool:
+        return False
+
+    def payment_refund_supported(self, payment: OrderPayment) -> bool:
+        return False
+
+    def payment_partial_refund_supported(self, payment: OrderPayment) -> bool:
+        return False
+
+    def execute_payment(self, request: HttpRequest, payment: OrderPayment):
+        raise PaymentException(_("This payment provider exists for historical purposes only and is no longer usable."))
+
+    def execute_refund(self, refund: OrderRefund):
+        raise PaymentException(_("This payment provider exists for historical purposes only and is no longer usable."))
+
+
 @receiver(register_payment_providers, dispatch_uid="payment_free")
 def register_payment_provider(sender, **kwargs):
     return [FreeOrderProvider, BoxOfficeProvider, OffsettingProvider, ManualPayment, GiftCardPayment]

src/pretix/base/signals.py

@@ -535,8 +535,9 @@ EventPluginRegistry = PluginAwareRegistry  # for backwards compatibility
 event_live_issues = EventPluginSignal()
 """
 This signal is sent out to determine whether an event can be taken live. If you want to
-prevent the event from going live, return a string that will be displayed to the user
-as the error message. If you don't, your receiver should return ``None``.
+prevent the event from going live, return an error message to display to the user (either
+as a SafeString containing HTML, or a string that will be HTML-escaped). If you don't,
+your receiver should return ``None``.
 
 As with all event-plugin signals, the ``sender`` keyword argument will contain the event.
 """

src/pretix/base/templatetags/eventsignal.py

@@ -22,6 +22,7 @@
 import importlib
 
 from django import template
+from django.utils.html import conditional_escape
 from django.utils.safestring import mark_safe
 
 from pretix.base.models import Event
@@ -44,7 +45,7 @@ def eventsignal(event: Event, signame: str, **kwargs):
     _html = []
     for receiver, response in signal.send(event, **kwargs):
         if response:
-            _html.append(response)
+            _html.append(conditional_escape(response))
     return mark_safe("".join(_html))
 
 
@@ -63,5 +64,5 @@ def signal(signame: str, request, **kwargs):
     _html = []
     for receiver, response in signal.send(request, **kwargs):
         if response:
-            _html.append(response)
+            _html.append(conditional_escape(response))
     return mark_safe("".join(_html))

src/pretix/base/views/errors.py

@@ -27,11 +27,11 @@ from django.template import TemplateDoesNotExist, loader
 from django.template.loader import get_template
 from django.utils.functional import Promise
 from django.utils.translation import gettext as _
-from django.views.decorators.csrf import requires_csrf_token
 from sentry_sdk import last_event_id
 
 from pretix.base.i18n import language
 from pretix.base.middleware import get_language_from_request
+from pretix.multidomain.middlewares import requires_csrf_token
 
 
 def csrf_failure(request, reason=""):

src/pretix/control/signals.py

@@ -39,7 +39,8 @@ from pretix.base.signals import (
 html_page_start = GlobalSignal()
 """
 This signal allows you to put code in the beginning of the main page for every
-page in the backend. You are expected to return HTML.
+page in the backend. You are expected to return a SafeString containing HTML, or
+a string that will be HTML-escaped.
 
 The ``sender`` keyword argument will contain the request.
 """
@@ -129,7 +130,7 @@ event_dashboard_top = EventPluginSignal()
 Arguments: 'request'
 
 This signal is sent out to include custom HTML in the top part of the the event dashboard.
-Receivers should return HTML.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 An additional keyword argument ``subevent`` *can* contain a sub-event.
@@ -172,6 +173,7 @@ Arguments: 'form'
 
 This signal allows you to add additional HTML to the form that is used for modifying vouchers.
 You receive the form object in the ``form`` keyword argument.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -209,6 +211,7 @@ Arguments: 'quota'
 
 This signal allows you to append HTML to a Quota's detail view. You receive the
 quota as argument in the ``quota`` keyword argument.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -219,6 +222,7 @@ Arguments: 'subevent'
 
 This signal allows you to append HTML to a SubEvent's detail view. You receive the
 subevent as argument in the ``subevent`` keyword argument.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -265,7 +269,8 @@ order_info = EventPluginSignal()
 """
 Arguments: ``order``, ``request``
 
-This signal is sent out to display additional information on the order detail page
+This signal is sent out to display additional information on the order detail page.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 Additionally, the argument ``order`` and ``request`` are available.
@@ -275,7 +280,8 @@ order_approve_info = EventPluginSignal()
 """
 Arguments: ``order``, ``request``
 
-This signal is sent out to display additional information on the order approve page
+This signal is sent out to display additional information on the order approve page.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 Additionally, the argument ``order`` and ``request`` are available.
@@ -286,6 +292,7 @@ order_position_buttons = EventPluginSignal()
 Arguments: ``order``, ``position``, ``request``
 
 This signal is sent out to display additional buttons for a single position of an order.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 Additionally, the argument ``order`` and ``request`` are available.
@@ -315,6 +322,7 @@ Arguments: 'request'
 
 This signal is sent out to include template snippets on the settings page of an event
 that allows generating a pretix Widget code.
+Receivers should return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 A second keyword argument ``request`` will contain the request object.

src/pretix/control/templates/pretixcontrol/event/live.html

@@ -19,7 +19,7 @@
                         </p>
                         <ul>
                             {% for issue in issues %}
-                                <li>{{ issue|safe }}</li>
+                                <li>{{ issue }}</li>
                             {% endfor %}
                         </ul>
                     </div>
@@ -42,7 +42,7 @@
                         </p>
                         <ul>
                             {% for issue in issues %}
-                                <li>{{ issue|safe }}</li>
+                                <li>{{ issue }}</li>
                             {% endfor %}
                         </ul>
                     </div>

src/pretix/control/views/auth.py

@@ -243,7 +243,8 @@ def invite(request, token):
     if request.user.is_authenticated:
         if inv.team.members.filter(pk=request.user.pk).exists():
             messages.error(request, _('You cannot accept the invitation for "{}" as you already are part of '
-                                      'this team.').format(inv.team.name))
+                                      'this team. If you want to add a different user or create a new account, '
+                                      'log out and click the invitation link again.').format(inv.team.name))
             return redirect('control:index')
         else:
             with transaction.atomic():

src/pretix/helpers/cookies.py

@@ -19,7 +19,9 @@
 # You should have received a copy of the GNU Affero General Public License along with this program.  If not, see
 # <https://www.gnu.org/licenses/>.
 #
+import itertools
 import re
+from http.cookies import Morsel
 
 from django.conf import settings
 
@@ -48,6 +50,41 @@ def set_cookie_without_samesite(request, response, key, *args, **kwargs):
         response.cookies[key]['Partitioned'] = True
 
 
+def thoroughly_delete_cookie(response, cookie_name, **kwargs):
+    """ Deletes different possible versions of a cookie (SameSite, Partitioned) """
+    properties = {"SameSite": ["", 'None'], "Partitioned": ["", True]}
+    for i, values in enumerate(itertools.product(*properties.values())):
+        m = Morsel()
+        m.set(cookie_name, '', '')
+        m.update(kwargs)
+        m.update(zip(properties.keys(), values))
+        m['expires'] = "Thu, 01 Jan 1970 00:00:00 GMT"
+
+        response.cookies[f'___DELETECOOKIE__{i}___{cookie_name}'] = m
+
+    # Make sure settings a cookie afterwards will add a new item in the dictionary, placing
+    # it below our deletion headers.
+    response.cookies.pop(cookie_name, None)
+
+
+def get_all_values_of_cookie(cookie_header, cookie_name):
+    # like django.http.cookie.parse_cookie, but returns all values of duplicated cookies instead of only the last
+    values = list()
+    if not cookie_header:
+        return values
+    for chunk in cookie_header.split(";"):
+        if "=" in chunk:
+            key, val = chunk.split("=", 1)
+        else:
+            # Assume an empty name per
+            # https://bugzilla.mozilla.org/show_bug.cgi?id=169091
+            key, val = "", chunk
+        key, val = key.strip(), val.strip()
+        if key == cookie_name:
+            values.append(val)
+    return values
+
+
 # Based on https://www.chromium.org/updates/same-site/incompatible-clients
 # Copyright 2019 Google LLC.
 # SPDX-License-Identifier: Apache-2.0

src/pretix/multidomain/middlewares.py

@@ -34,8 +34,6 @@
 
 import logging
 import time
-from datetime import datetime
-from http.cookies import Morsel
 from urllib.parse import urlparse
 
 from django.conf import settings
@@ -53,12 +51,16 @@ from django.middleware.csrf import (
 from django.shortcuts import render
 from django.urls import set_urlconf
 from django.utils.cache import patch_vary_headers
+from django.utils.decorators import decorator_from_middleware
 from django.utils.deprecation import MiddlewareMixin
 from django.utils.http import http_date
 from django_scopes import scopes_disabled
 
 from pretix.base.models import Event, Organizer
-from pretix.helpers.cookies import set_cookie_without_samesite
+from pretix.helpers.cookies import (
+    get_all_values_of_cookie, set_cookie_without_samesite,
+    thoroughly_delete_cookie,
+)
 from pretix.multidomain.models import KnownDomain
 
 logger = logging.getLogger(__name__)
@@ -181,9 +183,23 @@ class SessionMiddleware(BaseSessionMiddleware):
             # The session should be deleted only if the session is entirely empty
             is_secure = request.scheme == 'https'
             if '__Host-' + settings.SESSION_COOKIE_NAME in request.COOKIES and empty:
-                response.delete_cookie('__Host-' + settings.SESSION_COOKIE_NAME)
+                # response.delete_cookie does not work as we might have set a partitioned cookie
+                thoroughly_delete_cookie(
+                    response,
+                    '__Host-' + settings.SESSION_COOKIE_NAME,
+                    path=settings.SESSION_COOKIE_PATH,
+                    secure=is_secure,
+                    httponly=settings.SESSION_COOKIE_HTTPONLY or None
+                )
             elif settings.SESSION_COOKIE_NAME in request.COOKIES and empty:
-                response.delete_cookie(settings.SESSION_COOKIE_NAME)
+                # response.delete_cookie does not work as we might have set a partitioned cookie
+                thoroughly_delete_cookie(
+                    response,
+                    settings.SESSION_COOKIE_NAME,
+                    path=settings.SESSION_COOKIE_PATH,
+                    secure=is_secure,
+                    httponly=settings.SESSION_COOKIE_HTTPONLY or None
+                )
             else:
                 if accessed:
                     patch_vary_headers(response, ('Cookie',))
@@ -200,15 +216,21 @@ class SessionMiddleware(BaseSessionMiddleware):
                     if response.status_code != 500:
                         request.session.save()
                         if is_secure and settings.SESSION_COOKIE_NAME in request.COOKIES:  # remove legacy cookie
-                            response.delete_cookie(settings.SESSION_COOKIE_NAME)
-                            response.delete_cookie(settings.SESSION_COOKIE_NAME, samesite="None")
+                            # response.delete_cookie does not work as we might have set a partitioned cookie
+                            thoroughly_delete_cookie(
+                                response,
+                                settings.SESSION_COOKIE_NAME,
+                                path=settings.SESSION_COOKIE_PATH,
+                                secure=is_secure,
+                                httponly=settings.SESSION_COOKIE_HTTPONLY or None
+                            )
                         set_cookie_without_samesite(
                             request, response,
                             '__Host-' + settings.SESSION_COOKIE_NAME if is_secure else settings.SESSION_COOKIE_NAME,
                             request.session.session_key, max_age=max_age,
                             expires=expires,
                             path=settings.SESSION_COOKIE_PATH,
-                            secure=request.scheme == 'https',
+                            secure=is_secure,
                             httponly=settings.SESSION_COOKIE_HTTPONLY or None
                         )
         return response
@@ -253,75 +275,74 @@ class CsrfViewMiddleware(BaseCsrfMiddleware):
             if request.session.get(CSRF_SESSION_KEY) != request.META["CSRF_COOKIE"]:
                 request.session[CSRF_SESSION_KEY] = request.META["CSRF_COOKIE"]
         else:
-            is_secure = request.scheme == 'https'
             # Set the CSRF cookie even if it's already set, so we renew
             # the expiry timer.
-            if is_secure and settings.CSRF_COOKIE_NAME in request.COOKIES:  # remove legacy cookie
-                response.delete_cookie(settings.CSRF_COOKIE_NAME)
-                response.delete_cookie(settings.CSRF_COOKIE_NAME, samesite="None")
+
+            # remove legacy cookie
+            if request.is_secure() and settings.CSRF_COOKIE_NAME in request.COOKIES:
+                thoroughly_delete_cookie(
+                    response,
+                    settings.CSRF_COOKIE_NAME,
+                    path=settings.CSRF_COOKIE_PATH,
+                    secure=request.is_secure(),
+                    httponly=settings.CSRF_COOKIE_HTTPONLY
+                )
 
             handle_duplicated_csrftoken(request, response)
 
             set_cookie_without_samesite(
                 request, response,
-                '__Host-' + settings.CSRF_COOKIE_NAME if is_secure else settings.CSRF_COOKIE_NAME,
+                '__Host-' + settings.CSRF_COOKIE_NAME if request.is_secure() else settings.CSRF_COOKIE_NAME,
                 request.META["CSRF_COOKIE"],
                 max_age=settings.CSRF_COOKIE_AGE,
                 path=settings.CSRF_COOKIE_PATH,
-                secure=is_secure,
+                secure=request.is_secure(),
                 httponly=settings.CSRF_COOKIE_HTTPONLY
             )
             # Content varies with the CSRF cookie, so set the Vary header.
             patch_vary_headers(response, ('Cookie',))
 
+    def process_response(self, request, response):
+        if (
+            not settings.CSRF_USE_SESSIONS
+            and request.is_secure()
+            and settings.CSRF_COOKIE_NAME in response.cookies
+            and response.cookies[settings.CSRF_COOKIE_NAME].value
+        ):
+            logger.warning("Usage of djangos CsrfViewMiddleware detected (legacy cookie found in response). "
+                           "This may be caused by using csrf_project or requires_csrf_token from django.views.decorators.csrf. "
+                           "Use the pretix.multidomain.middlewares equivalent instead.")
+
+        return super().process_response(request, response)
+
 
 def handle_duplicated_csrftoken(request, response):
-    # Due to a Safari bug, in some browser, two csrftoken cookies with different values
-    # exist: one unpartitioned, one partitioned. This function generates an additional
+    # Due to a Safari bug, in some browser, two csrftoken cookies can exist:
+    # one unpartitioned, one partitioned. This function generates an additional
     # Set-Cookie header to get rid of the unpartitioned one.
 
     cookie_name = '__Host-' + settings.CSRF_COOKIE_NAME
 
-    if request.scheme == 'https' and cookie_name in request.COOKIES:
+    if request.is_secure() and cookie_name in request.COOKIES:
         values = get_all_values_of_cookie(request.headers.get('Cookie'), cookie_name)
         if len(values) > 1:
             logger.info('Trying to remove duplicated %s cookies: %r', cookie_name, values)
-
-            # Make sure the set_cookie_without_samesite below will add a new item in the dictionary, placing
-            # it below our deletion header.
-            response.cookies.pop(cookie_name, None)
-
-            # Add the deletion Set-Cookie header to the cookie dict under a wrong name, so it doesn't get
-            # overwritten by the set_cookie_without_samesite call below.  This works because the code in
-            # django.core.handlers.wsgi/asgi, that generates the actual Set-Cookie headers, only iterates
-            # over cookie.values(), ignoring the keys.
-            response.cookies['___DELETECOOKIE___' + cookie_name] = make_delete_morsel(cookie_name)
+            thoroughly_delete_cookie(
+                response,
+                cookie_name,
+                secure=request.is_secure(),
+                path=settings.CSRF_COOKIE_PATH,
+                httponly=settings.CSRF_COOKIE_HTTPONLY
+            )
 
 
-def get_all_values_of_cookie(cookie_header, cookie_name):
-    # like django.http.cookie.parse_cookie, but returns all values of duplicated cookies instead of only the last
-    values = list()
-    if not cookie_header:
-        return values
-    for chunk in cookie_header.split(";"):
-        if "=" in chunk:
-            key, val = chunk.split("=", 1)
-        else:
-            # Assume an empty name per
-            # https://bugzilla.mozilla.org/show_bug.cgi?id=169091
-            key, val = "", chunk
-        key, val = key.strip(), val.strip()
-        if key == cookie_name:
-            values.append(val)
-    return values
+csrf_protect = decorator_from_middleware(CsrfViewMiddleware)
 
 
-def make_delete_morsel(name):
-    m = Morsel()
-    m.set(name, '', '')
-    m['expires'] = datetime.utcfromtimestamp(0).strftime("%a, %d %b %Y %H:%M:%S GMT")
-    m['samesite'] = 'None'
-    m['secure'] = True
-    m['path'] = settings.CSRF_COOKIE_PATH
-    m['httponly'] = settings.CSRF_COOKIE_HTTPONLY
-    return m
+class _EnsureCsrfToken(CsrfViewMiddleware):
+    # Behave like CsrfViewMiddleware but don't reject requests or log warnings.
+    def _reject(self, request, reason):
+        return None
+
+
+requires_csrf_token = decorator_from_middleware(_EnsureCsrfToken)

src/pretix/plugins/badges/signals.py

@@ -26,6 +26,7 @@ from collections import defaultdict
 from django.dispatch import receiver
 from django.template.loader import get_template
 from django.urls import resolve, reverse
+from django.utils.safestring import mark_safe
 from django.utils.translation import gettext_lazy as _
 
 from pretix.base.logentrytypes import EventLogEntryType, log_entry_types
@@ -153,7 +154,7 @@ def control_order_position_info(sender: Event, position, request, order: Order,
         'event': sender,
         'position': position
     }
-    return template.render(ctx, request=request).strip()
+    return mark_safe(template.render(ctx, request=request).strip())
 
 
 @receiver(order_info, dispatch_uid="badges_control_order_info")

src/pretix/plugins/ticketoutputpdf/signals.py

@@ -189,7 +189,7 @@ def control_order_position_info(sender: Event, position, request, order, **kwarg
         'position': position,
         'layouts': layouts,
     }
-    return template.render(ctx, request=request).strip()
+    return template.render(ctx, request=request)
 
 
 override_layout = EventPluginSignal()

src/pretix/presale/signals.py

@@ -161,7 +161,8 @@ voucher_redeem_info = EventPluginSignal()
 """
 Arguments: ``voucher``
 
-This signal is sent out to display additional information on the "redeem a voucher" page
+This signal is sent out to display additional information on the "redeem a voucher" page.
+You are expected to return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -194,6 +195,7 @@ Arguments: ``request``
 
 This signals allows you to add HTML content to the confirmation page that is presented at the
 end of the checkout process, just before the order is being created.
+You are expected to return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event. A ``request``
 argument will contain the request object.
@@ -276,7 +278,8 @@ order_info = EventPluginSignal()
 """
 Arguments: ``order``, ``request``
 
-This signal is sent out to display additional information on the order detail page
+This signal is sent out to display additional information on the order detail page.
+Return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -285,7 +288,8 @@ position_info = EventPluginSignal()
 """
 Arguments: ``order``, ``position``, ``request``
 
-This signal is sent out to display additional information on the position detail page
+This signal is sent out to display additional information on the position detail page.
+Return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -294,7 +298,8 @@ order_info_top = EventPluginSignal()
 """
 Arguments: ``order``, ``request``
 
-This signal is sent out to display additional information on top of the order detail page
+This signal is sent out to display additional information on top of the order detail page.
+Return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -303,7 +308,8 @@ position_info_top = EventPluginSignal()
 """
 Arguments: ``order``, ``position``, ``request``
 
-This signal is sent out to display additional information on top of the position detail page
+This signal is sent out to display additional information on top of the position detail page.
+Return a SafeString containing HTML, or a string that will be HTML-escaped.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event.
 """
@@ -349,7 +355,7 @@ This signal is sent out to display additional information on the frontpage above
 of products and but below a custom frontpage text.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event. The
-receivers are expected to return HTML.
+receivers are expected to return a SafeString containing HTML, or a string that will be HTML-escaped.
 """
 
 render_seating_plan = EventPluginSignal()
@@ -361,7 +367,7 @@ You will be passed the ``request`` as a keyword argument. If applicable, a ``sub
 ``voucher`` argument might be given.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event. The
-receivers are expected to return HTML.
+receivers are expected to return a SafeString containing HTML, or a string that will be HTML-escaped.
 """
 
 front_page_bottom = EventPluginSignal()
@@ -372,7 +378,7 @@ This signal is sent out to display additional information on the frontpage below
 of products.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event. The
-receivers are expected to return HTML.
+receivers are expected to return a SafeString containing HTML, or a string that will be HTML-escaped.
 """
 
 front_page_bottom_widget = EventPluginSignal()
@@ -383,7 +389,7 @@ This signal is sent out to display additional information on the frontpage below
 of products if the front page is shown in the widget.
 
 As with all event plugin signals, the ``sender`` keyword argument will contain the event. The
-receivers are expected to return HTML.
+receivers are expected to return a SafeString containing HTML, or a string that will be HTML-escaped.
 """
 
 checkout_all_optional = EventPluginSignal()
@@ -403,7 +409,7 @@ Arguments: ``item``, ``variation``, ``subevent``
 
 This signal is sent out when the description of an item or variation is rendered and allows you to append
 additional text to the description. You are passed the ``item``, ``variation`` and ``subevent``. You are
-expected to return HTML.
+expected to return markdown.
 """
 
 register_cookie_providers = EventPluginSignal()

src/pretix/presale/views/customer.py

@@ -44,7 +44,6 @@ from django.utils.http import url_has_allowed_host_and_scheme
 from django.utils.safestring import mark_safe
 from django.utils.translation import gettext_lazy as _
 from django.views.decorators.cache import never_cache
-from django.views.decorators.csrf import csrf_protect
 from django.views.decorators.debug import sensitive_post_parameters
 from django.views.generic import FormView, ListView, View
 
@@ -101,7 +100,6 @@ class LoginView(RedirectBackMixin, FormView):
     redirect_authenticated_user = True
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -213,7 +211,6 @@ class RegistrationView(RedirectBackMixin, FormView):
     redirect_authenticated_user = True
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -257,7 +254,6 @@ class SetPasswordView(FormView):
     template_name = 'pretixpresale/organizers/customer_setpassword.html'
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -301,7 +297,6 @@ class ResetPasswordView(FormView):
     template_name = 'pretixpresale/organizers/customer_resetpw.html'
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -527,7 +522,6 @@ class ChangePasswordView(CustomerAccountBaseMixin, FormView):
     form_class = ChangePasswordForm
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -561,7 +555,6 @@ class ChangeInformationView(CustomerAccountBaseMixin, FormView):
     form_class = ChangeInfoForm
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -669,7 +662,6 @@ class SSOLoginView(RedirectBackMixin, View):
     redirect_authenticated_user = True
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts:
@@ -732,7 +724,6 @@ class SSOLoginReturnView(RedirectBackMixin, View):
     redirect_authenticated_user = True
 
     @method_decorator(sensitive_post_parameters())
-    @method_decorator(csrf_protect)
     @method_decorator(never_cache)
     def dispatch(self, request, *args, **kwargs):
         if not request.organizer.settings.customer_accounts: