Add policy for apexd.

apexd is a new daemon for managing APEX packages installed
on the device. It hosts a single binder service, "apexservice".

Bug: 112455435
Test: builds, binder service can be registered,
      apexes can be accessed, verified and mounted
Change-Id: I634ad100f10b2edcd9a9c0df0d33896fa5d4ed97
diff --git a/private/apexd.te b/private/apexd.te
new file mode 100644
index 0000000..dcec248
--- /dev/null
+++ b/private/apexd.te
@@ -0,0 +1,42 @@
+typeattribute apexd coredomain;
+
+init_daemon_domain(apexd)
+
+# Read /system/etc/security/apex_debug_key
+allow apexd apex_key_file:dir search;
+allow apexd apex_key_file:file r_file_perms;
+
+# Allow reading and writing of APEX files in the APEX data dir
+allow apexd apex_data_file:dir rw_dir_perms;
+allow apexd apex_data_file:file rw_file_perms;
+
+# allow apexd to create loop devices with /dev/loop-control
+allow apexd loop_control_device:chr_file rw_file_perms;
+# allow apexd to access loop devices
+allow apexd loop_device:blk_file rw_file_perms;
+# allow apexd to access /dev/block
+allow apexd block_device:dir r_dir_perms;
+
+# allow apexd to access /dev/block/dm-* (device-mapper entries)
+allow apexd dm_device:chr_file rw_file_perms;
+allow apexd dm_device:blk_file rw_file_perms;
+
+# sys_admin is required to access the device-mapper and mount
+allow apexd self:global_capability_class_set sys_admin;
+
+# allow apexd to create a mount point in /apex
+allow apexd apex_mnt_dir:dir create_dir_perms;
+# allow apexd to mount in /apex
+allow apexd apex_mnt_dir:filesystem { mount unmount };
+allow apexd apex_mnt_dir:dir mounton;
+# Unmount and mount filesystems
+allow apexd labeledfs:filesystem { mount unmount };
+
+# Spawning a libbinder thread results in a dac_override deny,
+# /dev/cpuset/tasks is owned by system.
+#
+# See b/35323867#comment3
+dontaudit apexd self:global_capability_class_set { dac_override dac_read_search };
+
+neverallow { domain -apexd -init } apex_data_file:dir no_w_dir_perms;
+neverallow { domain -apexd -init } apex_data_file:file no_rw_file_perms;
diff --git a/private/atrace.te b/private/atrace.te
index 2a7ccd0..37e9702 100644
--- a/private/atrace.te
+++ b/private/atrace.te
@@ -31,6 +31,7 @@
 
 allow atrace {
   service_manager_type
+  -apex_service
   -incident_service
   -netd_service
   -stats_service
diff --git a/private/compat/26.0/26.0.ignore.cil b/private/compat/26.0/26.0.ignore.cil
index 7e3fdbc..f985d95 100644
--- a/private/compat/26.0/26.0.ignore.cil
+++ b/private/compat/26.0/26.0.ignore.cil
@@ -9,6 +9,13 @@
     adb_service
     adbd_exec
     app_binding_service
+    apex_data_file
+    apex_mnt_dir
+    apex_key_file
+    apex_service
+    apexd
+    apexd_exec
+    apexd_tmpfs
     atrace
     binder_calls_stats_service
     biometric_service
diff --git a/private/compat/27.0/27.0.ignore.cil b/private/compat/27.0/27.0.ignore.cil
index 7d5017d..df3f95a 100644
--- a/private/compat/27.0/27.0.ignore.cil
+++ b/private/compat/27.0/27.0.ignore.cil
@@ -8,6 +8,13 @@
     activity_task_service
     adb_service
     app_binding_service
+    apex_data_file
+    apex_mnt_dir
+    apex_key_file
+    apex_service
+    apexd
+    apexd_exec
+    apexd_tmpfs
     atrace
     binder_calls_stats_service
     biometric_service
diff --git a/private/compat/28.0/28.0.ignore.cil b/private/compat/28.0/28.0.ignore.cil
index 63cfcb8..c1b126b 100644
--- a/private/compat/28.0/28.0.ignore.cil
+++ b/private/compat/28.0/28.0.ignore.cil
@@ -8,6 +8,13 @@
     activity_task_service
     adb_service
     app_binding_service
+    apex_data_file
+    apex_mnt_dir
+    apex_key_file
+    apex_service
+    apexd
+    apexd_exec
+    apexd_tmpfs
     biometric_service
     ;; TODO(b/116344577): remove after the issue is resolved
     buffer_hub_service
diff --git a/private/crash_dump.te b/private/crash_dump.te
index 831ff04..fe25bad 100644
--- a/private/crash_dump.te
+++ b/private/crash_dump.te
@@ -2,6 +2,7 @@
 
 allow crash_dump {
   domain
+  -apexd
   -bpfloader
   -crash_dump
   -init
diff --git a/private/file_contexts b/private/file_contexts
index 991f75b..2e78b80 100644
--- a/private/file_contexts
+++ b/private/file_contexts
@@ -30,6 +30,7 @@
 /postinstall        u:object_r:postinstall_mnt_dir:s0
 /proc               u:object_r:rootfs:s0
 /sys                u:object_r:sysfs:s0
+/apex               u:object_r:apex_mnt_dir:s0
 
 # Symlinks
 /bin                u:object_r:rootfs:s0
@@ -287,6 +288,7 @@
 /system/etc/ld\.config.*                u:object_r:system_linker_config_file:s0
 /system/etc/seccomp_policy(/.*)?        u:object_r:system_seccomp_policy_file:s0
 /system/etc/security/cacerts(/.*)?      u:object_r:system_security_cacerts_file:s0
+/system/etc/security/apex(/.*)?     u:object_r:apex_key_file:s0
 /system/etc/selinux/mapping/[0-9]+\.[0-9]+\.cil       u:object_r:sepolicy_file:s0
 /system/etc/selinux/plat_mac_permissions\.xml u:object_r:mac_perms_file:s0
 /system/etc/selinux/plat_property_contexts  u:object_r:property_contexts_file:s0
@@ -305,6 +307,7 @@
 /system/bin/bpfloader            u:object_r:bpfloader_exec:s0
 /system/bin/wait_for_keymaster   u:object_r:wait_for_keymaster_exec:s0
 /system/bin/watchdogd            u:object_r:watchdogd_exec:s0
+/system/bin/apexd                u:object_r:apexd_exec:s0
 
 #############################
 # Vendor files
@@ -387,6 +390,7 @@
 /data/ota_package(/.*)? u:object_r:ota_package_file:s0
 /data/adb(/.*)?		u:object_r:adb_data_file:s0
 /data/anr(/.*)?		u:object_r:anr_data_file:s0
+/data/apex(/.*)?		u:object_r:apex_data_file:s0
 /data/app(/.*)?                       u:object_r:apk_data_file:s0
 /data/app/[^/]+/oat(/.*)?                u:object_r:dalvikcache_data_file:s0
 /data/app/vmdl[^/]+\.tmp(/.*)?           u:object_r:apk_tmp_file:s0
diff --git a/private/llkd.te b/private/llkd.te
index 3f84eb6..385f930 100644
--- a/private/llkd.te
+++ b/private/llkd.te
@@ -22,6 +22,7 @@
 userdebug_or_eng(`
   allow llkd {
     domain
+    -apexd
     -kernel
     -keystore
     -init
diff --git a/private/service_contexts b/private/service_contexts
index e04227b..b68ab8e 100644
--- a/private/service_contexts
+++ b/private/service_contexts
@@ -8,6 +8,7 @@
 android.security.keystore                 u:object_r:keystore_service:s0
 android.service.gatekeeper.IGateKeeperService    u:object_r:gatekeeper_service:s0
 app_binding                               u:object_r:app_binding_service:s0
+apexservice                               u:object_r:apex_service:s0
 appops                                    u:object_r:appops_service:s0
 appwidget                                 u:object_r:appwidget_service:s0
 assetatlas                                u:object_r:assetatlas_service:s0
diff --git a/private/system_app.te b/private/system_app.te
index 4ed1982..245496f 100644
--- a/private/system_app.te
+++ b/private/system_app.te
@@ -70,6 +70,7 @@
 # TODO: scope this down? Too broad?
 allow system_app {
   service_manager_type
+  -apex_service
   -dumpstate_service
   -installd_service
   -netd_service
diff --git a/public/apexd.te b/public/apexd.te
new file mode 100644
index 0000000..73daf38
--- /dev/null
+++ b/public/apexd.te
@@ -0,0 +1,11 @@
+# apexd -- manager for APEX packages
+type apexd, domain;
+type apexd_exec, exec_type, file_type, system_file_type;
+
+binder_use(apexd)
+add_service(apexd, apex_service)
+
+neverallow { domain -init -apexd } apex_service:service_manager find;
+neverallow { domain -init -apexd } apexd:binder call;
+
+neverallow domain apexd:process ptrace;
diff --git a/public/domain.te b/public/domain.te
index 5e8fb23..176ab48 100644
--- a/public/domain.te
+++ b/public/domain.te
@@ -434,7 +434,7 @@
 # Limit what domains can mount filesystems or change their mount flags.
 # sdcard_type / vfat is exempt as a larger set of domains need
 # this capability, including device-specific domains.
-neverallow { domain -kernel -init -recovery -vold -zygote -update_engine -otapreopt_chroot } { fs_type -sdcard_type }:filesystem { mount remount relabelfrom relabelto };
+neverallow { domain -kernel -init -recovery -vold -zygote -update_engine -otapreopt_chroot -apexd } { fs_type -sdcard_type }:filesystem { mount remount relabelfrom relabelto };
 
 #
 # Assert that, to the extent possible, we're not loading executable content from
diff --git a/public/dumpstate.te b/public/dumpstate.te
index 2d226af..5663e80 100644
--- a/public/dumpstate.te
+++ b/public/dumpstate.te
@@ -205,6 +205,7 @@
 
 allow dumpstate {
   service_manager_type
+  -apex_service
   -dumpstate_service
   -gatekeeper_service
   -incident_service
diff --git a/public/file.te b/public/file.te
index 755bb98..016807e 100644
--- a/public/file.te
+++ b/public/file.te
@@ -140,6 +140,8 @@
 type system_linker_config_file, system_file_type, file_type;
 # Default type for linker config /system/etc/seccomp_policy/*.
 type system_seccomp_policy_file, system_file_type, file_type;
+# Default type for APEX keys in /system/etc/security/apex/*
+type apex_key_file, system_file_type, file_type;
 # Default type for cacerts in /system/etc/security/cacerts/*.
 type system_security_cacerts_file, system_file_type, file_type;
 # Default type for zoneinfo files in /system/usr/share/zoneinfo/*.
@@ -197,6 +199,8 @@
 type tombstone_data_file, file_type, data_file_type, core_data_file_type, mlstrustedobject;
 # /data/vendor/tombstones/wifi - vendor wifi dumps
 type tombstone_wifi_data_file, file_type, data_file_type;
+# /data/apex - APEX data files
+type apex_data_file, file_type, data_file_type, core_data_file_type;
 # /data/app - user-installed apps
 type apk_data_file, file_type, data_file_type, core_data_file_type;
 type apk_tmp_file, file_type, data_file_type, core_data_file_type, mlstrustedobject;
@@ -252,6 +256,9 @@
 # Mount location for read-write product partitions.
 type mnt_product_file, file_type;
 
+# Mount point used for APEX images
+type apex_mnt_dir, file_type;
+
 # /postinstall: Mount point used by update_engine to run postinstall.
 type postinstall_mnt_dir, file_type;
 # Files inside the /postinstall mountpoint are all labeled as postinstall_file.
diff --git a/public/init.te b/public/init.te
index 101c0c8..c337c82 100644
--- a/public/init.te
+++ b/public/init.te
@@ -80,6 +80,9 @@
 # Mount on /dev/usb-ffs/adb.
 allow init device:dir mounton;
 
+# Mount tmpfs on /apex
+allow init apex_mnt_dir:dir mounton;
+
 # Create and remove symlinks in /.
 allow init rootfs:lnk_file { create unlink };
 
@@ -514,6 +517,11 @@
 
 # Allow init to use binder
 binder_use(init);
+allow init apex_service:service_manager find;
+# Allow servicemanager to pass it
+allow servicemanager init:binder transfer;
+# Allow calls from init to apexd
+allow init apexd:binder call;
 
 ###
 ### neverallow rules
@@ -532,8 +540,11 @@
 # init should never execute a program without changing to another domain.
 neverallow init { file_type fs_type }:file execute_no_trans;
 
-# Init never adds or uses services via service_manager.
-neverallow init service_manager_type:service_manager { add find };
+# init can only find the APEX service
+neverallow init { service_manager_type -apex_service }:service_manager { find };
+# init can never add binder services
+neverallow init service_manager_type:service_manager { add };
+# init can never list binder services
 neverallow init servicemanager:service_manager list;
 
 # Init should not be creating subdirectories in /data/local/tmp
diff --git a/public/service.te b/public/service.te
index eaacabf..5e7ca4d 100644
--- a/public/service.te
+++ b/public/service.te
@@ -1,3 +1,4 @@
+type apex_service,              service_manager_type;
 type audioserver_service,       service_manager_type;
 type batteryproperties_service, app_api_service, ephemeral_app_api_service, service_manager_type;
 type bluetooth_service,         service_manager_type;
diff --git a/public/shell.te b/public/shell.te
index 7a0eb46..339b586 100644
--- a/public/shell.te
+++ b/public/shell.te
@@ -104,6 +104,7 @@
 # - dumpstate_service (so it can receive dumpstate progress updates)
 allow shell {
   service_manager_type
+  -apex_service
   -gatekeeper_service
   -incident_service
   -installd_service
diff --git a/public/traceur_app.te b/public/traceur_app.te
index 355ae77..c18984e 100644
--- a/public/traceur_app.te
+++ b/public/traceur_app.te
@@ -7,6 +7,7 @@
 
 allow traceur_app {
   service_manager_type
+  -apex_service
   -gatekeeper_service
   -incident_service
   -installd_service