Fix various errors in iMIP logic

Signed-off-by: Anna Larch <anna@nextcloud.com>

diff --git a/lib/private/Calendar/Manager.php b/lib/private/Calendar/Manager.php
index f0b8e9fd50de793333a3717a28c3a016e7e8b643..550ba36dd6bc32638acfb35f21861bf2f0129526 100644 (file)
--- a/lib/private/Calendar/Manager.php
+++ b/lib/private/Calendar/Manager.php
@@ -330,12 +330,27 @@ class Manager implements IManager {
                // to the email address in the ORGANIZER.
                // We don't want to accept a CANCEL request from just anyone
                $organizer = substr($vEvent->{'ORGANIZER'}->getValue(), 7);
-               if (strcasecmp($sender, $organizer) !== 0 && strcasecmp($replyTo, $organizer) !== 0) {
+               $isNotOrganizer = ($replyTo !== null) ? (strcasecmp($sender, $organizer) !== 0 && strcasecmp($replyTo, $organizer) !== 0) : (strcasecmp($sender, $organizer) !== 0);
+               if ($isNotOrganizer) {
                        $this->logger->warning('Sender must be the ORGANIZER of this event');
                        return false;
                }
 
+               //check if the event is in the future
+               /** @var DateTime $eventTime */
+               $eventTime = $vEvent->{'DTSTART'};
+               if ($eventTime->getDateTime()->getTimeStamp() < $this->timeFactory->getTime()) { // this might cause issues with recurrences
+                       $this->logger->warning('Only events in the future are processed');
+                       return false;
+               }
+
+               // Check if we have a calendar to work with
                $calendars = $this->getCalendarsForPrincipal($principalUri);
+               if (empty($calendars)) {
+                       $this->logger->warning('Could not find any calendars for principal ' . $principalUri);
+                       return false;
+               }
+
                $found = null;
                // if the attendee has been found in at least one calendar event with the UID of the iMIP event
                // we process it.