Allow read/write of sharing/permissions information
Allow developers to read and write sharing information of items and folders.
Brian Park commented
This information is currently available and documented here:
Unfortunately, permissions can only ever be retrieved in sets of what's attached to a given DriveItem (identified by ID or path). The same page states that the $expand odata param is not allowed for this collection.
OneDrive.com gets around this by using the SharePoint API's GetList method to obtain a list:
Then calls RenderListDataAsStream on it. I couldn't find documentation for this call, but here is a similar one: