NTFS permissions are stored in the file system, that is well known. But where are share permissions stored?
As so often with Windows: in the registry. Network shares are defined by only a handful of relatively simple registry entries stored in the server service's key which is, for historical reasons that go back way beyond OS/2, named "LanmanServer" (the workstation service is similarly named "LanmanWorkstation").
The share definitions can be found here:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\LanmanServer\Shares






