Add keystore_key:attest_unique_id to priv_app.

Only privileged apps are supposed to be able to get unique IDs from
attestation.

Test: CTS test verifies the negative condition, manual the positive
Bug: 34671471
Change-Id: I9ab3f71b1e11ed1d7866ff933feece73152d2578

private/access_vectors

@@ -702,6 +702,7 @@ class keystore_key
 	clear_uid
 	add_auth
 	user_changed
+	gen_unique_id
 }
 
 class drmservice {

private/domain.te

@@ -13,3 +13,6 @@ neverallow {
   -system_server
   userdebug_or_eng(`-perfprofd')
 } self:capability sys_ptrace;
+
+# Limit ability to generate hardware unique device ID attestations to priv_apps
+neverallow { domain -priv_app } *:keystore_key gen_unique_id;

private/priv_app.te

@@ -114,6 +114,9 @@ allow priv_app functionfs:file rw_file_perms;
 # TODO: narrow this to just MediaProvider
 allow priv_app mnt_media_rw_file:dir search;
 
+# Allow privileged apps (e.g. GMS core) to generate unique hardware IDs
+allow priv_app keystore:keystore_key gen_unique_id;
+
 read_runtime_log_tags(priv_app)
 
 ###