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The auth callbacks are then called with a Authentication auth object
if the returned element of the authobject is ROGO_AUTH_OBJ_SUCCESS then sets the username to be the authobject username and saves with auth plugin sucessfully authenticated.
if the returned element of the authobject is ROGO_AUTH_OBJ_LOOKUPONLY then it attempts to lookup the user using the userlookup function of the lookup stack. It then checks whats returned by this and sees if it has enough data to create a user and checks the flags from the lookup that it shouldnt create a user eg not unique user data found. If sucessfully creates user then it sets things as though it had successfully authenticated.
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