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Change behaviour regarding request header size for caldav requests.

Kerry Channing shared this idea 5 years ago
Open Discussion

As a system administrator, I'd like to adjust the limit for caldav request header size, so I can better support my customers who use outlook and synchronize their calendars with horde using caldav. Sometimes they send calendar invitations with an email attached, which may itself be a size larger than 100k. In that situation, I discovered that this causes caldav synchronisation to fail.


I ran into a problem syncing my Outlook calendar with caldav via caldav synchroniser, it failed without a specific error message to caldav. A log entry appeared in n /usr/local/cpanel/logs/cpdavd_error_log:-

DoS Protection Activated; PROPFIND larger than 100k discarded

It was working fine for a couple of weeks, could it be some kind of attachment on a calendar item causing a size limit to be exceeded? I recall dragging an outlook email to the calendar to create a calendar entry, and it's quite possible that that's what caused it to stop syncing.

I located the code that was triggering the error:-

  1. /usr/local/cpanel/Cpanel/
  2. if ( int $httphead->header('content-length') > 100000 ) {
  3. print STDERR "DoS Protection Activated; PROPFIND larger than 100k discarded\n";
  4. $self->force_last_request();
  5. }

I commented the code out and restarted httpd and it solved the issue.

Could the limit for caldav requests be increased or made customisable?

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