The planning guide for CRM 2013 says:
If you want to use Microsoft SharePoint document management functionality in Microsoft Dynamics CRM Server 2013, you have to have one of the following SharePoint editions installed and running:
- Microsoft SharePoint 2013
- Microsoft SharePoint Foundation 2013
- Microsoft SharePoint 2010 SP1 (all editions)
Does that means SharePoint Online through Office 365 is not supported?