Allow app to conntect to BufferHub service

Bug: 112940221
Test: AHardwareBufferTest
Change-Id: I1fd065844e03c7e079dc40b7f7dbb8968f1b00bc

private/app_neverallows.te

@@ -294,6 +294,7 @@ neverallow all_untrusted_apps {
 neverallow all_untrusted_apps {
   coredomain_hwservice
   -same_process_hwservice
+  -fwk_bufferhub_hwservice # Designed for use by any domain
   -hidl_allocator_hwservice # Designed for use by any domain
   -hidl_manager_hwservice # Designed for use by any domain
   -hidl_memory_hwservice # Designed for use by any domain

private/technical_debt.cil

@@ -50,3 +50,8 @@
 (typeattributeset untrusted_app_visible_hwservice_violators (untrusted_app_visible_hwservice))
 (typeattribute untrusted_app_visible_halserver)
 (typeattributeset untrusted_app_visible_halserver_violators (untrusted_app_visible_halserver))
+
+; Apps, except isolated apps, are clients of BufferHub HAL
+; Unfortunately, we can't currently express this in module policy language:
+;     typeattribute { appdomain -isolated_app } hal_cas_client;
+(typeattributeset hal_bufferhub_client ((and (appdomain) ((not (isolated_app))))))

public/fwk_bufferhub.te

 binder_call(hal_bufferhub_client, hal_bufferhub_server)
 binder_call(hal_bufferhub_server, hal_bufferhub_client)
 
-add_hwservice(hal_bufferhub_server, fwk_bufferhub_hwservice)
+hal_attribute_hwservice(hal_bufferhub, fwk_bufferhub_hwservice)