Minimize public policy

Ideally, public should only contain APIs (types / attributes) for
vendor. The other statements like allow/neverallow/typeattributes are
regarded as implementation detail for platform and should be in private.

Bug: 232023812
Test: m selinux_policy
Test: diff <(git diff --staged | grep "^-" | cut -b2- | sort) \
           <(git diff --staged | grep "^+" | cut -b2- | sort)
Test: remove comments on plat_sepolicy.cil, replace base_typeattr_*
      to base_typeattr and then compare old and new plat_sepolicy.cil
Change-Id: I5e7d2da4465ab0216de6bacdf03077d37f6ffe12
diff --git a/private/system_server.te b/private/system_server.te
index 7306773..acaa9e2 100644
--- a/private/system_server.te
+++ b/private/system_server.te
@@ -1281,6 +1281,10 @@
 # Allow system server to read profcollectd reports for upload.
 userdebug_or_eng(`r_dir_file(system_server, profcollectd_data_file)')
 
+# Power controls for debugging/diagnostics
+get_prop(system_server, power_debug_prop)
+set_prop(system_server, power_debug_prop)
+
 ###
 ### Neverallow rules
 ###
@@ -1616,10 +1620,18 @@
 # TODO(azilio): Remove system property after archiving testing is completed.
 get_prop(system_server, pm_archiving_enabled_prop)
 
+# Allow accessing /mnt/pre_reboot_dexopt/chroot, to load the new service-art.jar
+# in Pre-reboot Dexopt.
+allow system_server pre_reboot_dexopt_file:dir { getattr search };
+
 # Do not allow any domain other than init or system server to get or set the property
 neverallow { domain -init -system_server } crashrecovery_prop:property_service set;
 neverallow { domain -init -dumpstate -system_server } crashrecovery_prop:file no_rw_file_perms;
 
-# Allow accessing /mnt/pre_reboot_dexopt/chroot, to load the new service-art.jar
-# in Pre-reboot Dexopt.
-allow system_server pre_reboot_dexopt_file:dir { getattr search };
+neverallow {
+  domain
+  -init
+  -vendor_init
+  -system_server
+  -shell
+} power_debug_prop:property_service set;