platform_system_sepolicy/private/system_server.te

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#
# System Server aka system_server spawned by zygote.
# Most of the framework services run in this process.
#
typeattribute system_server domain_deprecated;
typeattribute system_server mlstrustedsubject;
# Define a type for tmpfs-backed ashmem regions.
tmpfs_domain(system_server)
# Create a socket for connections from crash_dump.
type_transition system_server system_data_file:sock_file system_ndebug_socket "ndebugsocket";
allow system_server zygote_tmpfs:file read;
# Create a socket for receiving info from wpa.
type_transition system_server wifi_data_file:sock_file system_wpa_socket;
type_transition system_server wpa_socket:sock_file system_wpa_socket;
# For art.
allow system_server dalvikcache_data_file:dir r_dir_perms;
allow system_server dalvikcache_data_file:file { r_file_perms execute };
# /data/resource-cache
allow system_server resourcecache_data_file:file r_file_perms;
allow system_server resourcecache_data_file:dir r_dir_perms;
# ptrace to processes in the same domain for debugging crashes.
allow system_server self:process ptrace;
# Child of the zygote.
allow system_server zygote:fd use;
allow system_server zygote:process sigchld;
# May kill zygote on crashes.
allow system_server zygote:process sigkill;
allow system_server crash_dump:process sigkill;
# Read /system/bin/app_process.
allow system_server zygote_exec:file r_file_perms;
# Needed to close the zygote socket, which involves getopt / getattr
allow system_server zygote:unix_stream_socket { getopt getattr };
# system server gets network and bluetooth permissions.
net_domain(system_server)
# in addition to ioctls whitelisted for all domains, also allow system_server
# to use privileged ioctls commands. Needed to set up VPNs.
allowxperm system_server self:udp_socket ioctl priv_sock_ioctls;
bluetooth_domain(system_server)
# These are the capabilities assigned by the zygote to the
# system server.
allow system_server self:capability {
ipc_lock
kill
net_admin
net_bind_service
net_broadcast
net_raw
sys_boot
sys_nice
sys_resource
sys_time
sys_tty_config
};
wakelock_use(system_server)
# Triggered by /proc/pid accesses, not allowed.
dontaudit system_server self:capability sys_ptrace;
# Trigger module auto-load.
allow system_server kernel:system module_request;
# Allow alarmtimers to be set
allow system_server self:capability2 wake_alarm;
# Use netlink uevent sockets.
allow system_server self:netlink_kobject_uevent_socket create_socket_perms_no_ioctl;
# Use generic netlink sockets.
allow system_server self:netlink_socket create_socket_perms_no_ioctl;
allow system_server self:netlink_generic_socket create_socket_perms_no_ioctl;
# Use generic "sockets" where the address family is not known
# to the kernel. The ioctl permission is specifically omitted here, but may
# be added to device specific policy along with the ioctl commands to be
# whitelisted.
allow system_server self:socket create_socket_perms_no_ioctl;
# Set and get routes directly via netlink.
allow system_server self:netlink_route_socket nlmsg_write;
# Kill apps.
allow system_server appdomain:process { sigkill signal };
# Set scheduling info for apps.
allow system_server appdomain:process { getsched setsched };
allow system_server audioserver:process { getsched setsched };
allow system_server hal_audio:process { getsched setsched };
allow system_server cameraserver:process { getsched setsched };
allow system_server hal_camera:process { getsched setsched };
allow system_server mediaserver:process { getsched setsched };
allow system_server bootanim:process { getsched setsched };
# Read /proc/pid data for all domains. This is used by ProcessCpuTracker
# within system_server to keep track of memory and CPU usage for
# all processes on the device. In addition, /proc/pid files access is needed
# for dumping stack traces of native processes.
r_dir_file(system_server, domain)
# Read/Write to /proc/net/xt_qtaguid/ctrl and and /dev/xt_qtaguid.
allow system_server qtaguid_proc:file rw_file_perms;
allow system_server qtaguid_device:chr_file rw_file_perms;
# Read /proc/uid_cputime/show_uid_stat.
allow system_server proc_uid_cputime_showstat:file r_file_perms;
# Write /proc/uid_cputime/remove_uid_range.
allow system_server proc_uid_cputime_removeuid:file { w_file_perms getattr };
# Write /proc/uid_procstat/set.
allow system_server proc_uid_procstat_set:file { w_file_perms getattr };
# Write to /proc/sysrq-trigger.
allow system_server proc_sysrq:file rw_file_perms;
# Read /proc/stat for CPU usage statistics
allow system_server proc_stat:file r_file_perms;
# Read /sys/kernel/debug/wakeup_sources.
allow system_server debugfs:file r_file_perms;
# The DhcpClient and WifiWatchdog use packet_sockets
allow system_server self:packet_socket create_socket_perms_no_ioctl;
# NetworkDiagnostics requires explicit bind() calls to ping sockets. These aren't actually the same
# as raw sockets, but the kernel doesn't yet distinguish between the two.
allow system_server node:rawip_socket node_bind;
# 3rd party VPN clients require a tun_socket to be created
allow system_server self:tun_socket create_socket_perms_no_ioctl;
# Talk to init and various daemons via sockets.
unix_socket_connect(system_server, lmkd, lmkd)
unix_socket_connect(system_server, mtpd, mtp)
unix_socket_connect(system_server, netd, netd)
unix_socket_connect(system_server, vold, vold)
unix_socket_connect(system_server, webview_zygote, webview_zygote)
unix_socket_connect(system_server, zygote, zygote)
unix_socket_connect(system_server, racoon, racoon)
# TODO(b/35707797): Remove this socket access.
unix_socket_send(system_server, wpa, hal_wifi_supplicant_server)
unix_socket_connect(system_server, uncrypt, uncrypt)
# Communicate over a socket created by surfaceflinger.
allow system_server surfaceflinger:unix_stream_socket { read write setopt };
# Perform Binder IPC.
binder_use(system_server)
binder_call(system_server, appdomain)
binder_call(system_server, binderservicedomain)
binder_call(system_server, dumpstate)
binder_call(system_server, fingerprintd)
binder_call(system_server, gatekeeperd)
binder_call(system_server, installd)
binder_call(system_server, incidentd)
binder_call(system_server, netd)
binder_call(system_server, wificond)
binder_service(system_server)
# Perform HwBinder IPC.
hwbinder_use(system_server)
hwallocator_use(system_server)
binder_call(system_server, hal_boot)
binder_call(system_server, hal_contexthub)
Switch Fingerprint HAL policy to _client/_server This switches Fingerprint HAL policy to the design which enables us to conditionally remove unnecessary rules from domains which are clients of Bluetooth HAL. Domains which are clients of Fingerprint HAL, such as system_server domain, are granted rules targeting hal_fingerprint only when the Fingerprint HAL runs in passthrough mode (i.e., inside the client's process). When the HAL runs in binderized mode (i.e., in another process/domain, with clients talking to the HAL over HwBinder IPC), rules targeting hal_fingerprint are not granted to client domains. Domains which offer a binderized implementation of Fingerprint HAL, such as hal_fingerprint_default domain, are always granted rules targeting hal_fingerprint. NOTE: This commit also removes unnecessary allow rules from Fingerprint HAL, such access to servicemanager (not hwservicemanager) and access to keystore daemon over Binder IPC. Fingerprint HAL does not use this functionality anyway and shouldn't use it either. Test: Enable fingerprint + PIN secure lock screen, confirm it unlocks with fingerprint or PIN Test: Disable PIN (and thus fingerprint) secure lock screen Test: make FingerprintDialog, install, make a fake purchase Test: Add fingerprint_hidl_hal_test to device.mk, build & add to device, adb shell stop, adb shell /data/nativetest64/fingerprint_hidl_hal_test/fingerprint_hidl_hal_test -- all tests pass Bug: 34170079 Change-Id: I6951c0f0640194c743ff7049357c77f5f21b71a1
2017-02-22 00:35:16 +01:00
hal_client_domain(system_server, hal_fingerprint)
binder_call(system_server, hal_gnss);
binder_call(system_server, hal_ir)
binder_call(system_server, hal_light)
binder_call(system_server, hal_memtrack)
binder_call(system_server, hal_power)
binder_call(system_server, hal_sensors)
binder_call(system_server, hal_thermal)
binder_call(system_server, hal_usb)
binder_call(system_server, hal_vibrator)
binder_call(system_server, hal_vr)
hal_client_domain(system_server, hal_wifi)
hal_client_domain(system_server, hal_wifi_supplicant)
# Talk to tombstoned to get ANR traces.
unix_socket_connect(system_server, tombstoned_intercept, tombstoned)
# Send signals to trigger ANR traces.
# This is derived from the list that system server defines as interesting native processes
# to dump during ANRs or watchdog aborts, defined in NATIVE_STACKS_OF_INTEREST in
# frameworks/base/services/core/java/com/android/server/Watchdog.java.
allow system_server {
audioserver
cameraserver
drmserver
inputflinger
mediacodec
mediadrmserver
mediaextractor
mediaserver
mediametrics
sdcardd
surfaceflinger
}:process { signal };
# Use sockets received over binder from various services.
allow system_server audioserver:tcp_socket rw_socket_perms;
allow system_server audioserver:udp_socket rw_socket_perms;
allow system_server mediaserver:tcp_socket rw_socket_perms;
allow system_server mediaserver:udp_socket rw_socket_perms;
# Use sockets received over binder from various services.
allow system_server mediadrmserver:tcp_socket rw_socket_perms;
allow system_server mediadrmserver:udp_socket rw_socket_perms;
# Check SELinux permissions.
selinux_check_access(system_server)
# XXX Label sysfs files with a specific type?
allow system_server sysfs:file rw_file_perms;
allow system_server sysfs_nfc_power_writable:file rw_file_perms;
allow system_server sysfs_devices_system_cpu:file w_file_perms;
allow system_server sysfs_mac_address:file r_file_perms;
allow system_server sysfs_thermal:dir search;
allow system_server sysfs_thermal:file r_file_perms;
# TODO: Remove when HALs are forced into separate processes
allow system_server sysfs_vibrator:file { write append };
# TODO: added to match above sysfs rule. Remove me?
allow system_server sysfs_usb:file w_file_perms;
# Access devices.
allow system_server device:dir r_dir_perms;
allow system_server mdns_socket:sock_file rw_file_perms;
allow system_server alarm_device:chr_file rw_file_perms;
allow system_server gpu_device:chr_file rw_file_perms;
allow system_server iio_device:chr_file rw_file_perms;
allow system_server input_device:dir r_dir_perms;
allow system_server input_device:chr_file rw_file_perms;
allow system_server radio_device:chr_file r_file_perms;
allow system_server tty_device:chr_file rw_file_perms;
allow system_server usbaccessory_device:chr_file rw_file_perms;
allow system_server video_device:dir r_dir_perms;
allow system_server video_device:chr_file rw_file_perms;
allow system_server adbd_socket:sock_file rw_file_perms;
allow system_server rtc_device:chr_file rw_file_perms;
allow system_server audio_device:dir r_dir_perms;
# write access needed for MIDI
allow system_server audio_device:chr_file rw_file_perms;
# tun device used for 3rd party vpn apps
allow system_server tun_device:chr_file rw_file_perms;
# Manage system data files.
allow system_server system_data_file:dir create_dir_perms;
allow system_server system_data_file:notdevfile_class_set create_file_perms;
allow system_server keychain_data_file:dir create_dir_perms;
allow system_server keychain_data_file:file create_file_perms;
allow system_server keychain_data_file:lnk_file create_file_perms;
# Manage /data/app.
allow system_server apk_data_file:dir create_dir_perms;
allow system_server apk_data_file:{ file lnk_file } { create_file_perms link };
allow system_server apk_tmp_file:dir create_dir_perms;
allow system_server apk_tmp_file:file create_file_perms;
# Manage /data/app-private.
allow system_server apk_private_data_file:dir create_dir_perms;
allow system_server apk_private_data_file:file create_file_perms;
allow system_server apk_private_tmp_file:dir create_dir_perms;
allow system_server apk_private_tmp_file:file create_file_perms;
# Manage files within asec containers.
allow system_server asec_apk_file:dir create_dir_perms;
allow system_server asec_apk_file:file create_file_perms;
allow system_server asec_public_file:file create_file_perms;
# Manage /data/anr.
allow system_server anr_data_file:dir create_dir_perms;
allow system_server anr_data_file:file create_file_perms;
# Read /data/misc/incidents - only read. The fd will be sent over binder,
# with no DAC access to it, for dropbox to read.
allow system_server incident_data_file:file read;
# Manage /data/backup.
allow system_server backup_data_file:dir create_dir_perms;
allow system_server backup_data_file:file create_file_perms;
# Write to /data/system/heapdump
allow system_server heapdump_data_file:dir rw_dir_perms;
allow system_server heapdump_data_file:file create_file_perms;
# Manage /data/misc/adb.
allow system_server adb_keys_file:dir create_dir_perms;
allow system_server adb_keys_file:file create_file_perms;
# Manage /data/misc/sms.
# TODO: Split into a separate type?
allow system_server radio_data_file:dir create_dir_perms;
allow system_server radio_data_file:file create_file_perms;
# Manage /data/misc/systemkeys.
allow system_server systemkeys_data_file:dir create_dir_perms;
allow system_server systemkeys_data_file:file create_file_perms;
# Access /data/tombstones.
allow system_server tombstone_data_file:dir r_dir_perms;
allow system_server tombstone_data_file:file r_file_perms;
# Manage /data/misc/vpn.
allow system_server vpn_data_file:dir create_dir_perms;
allow system_server vpn_data_file:file create_file_perms;
# Manage /data/misc/wifi.
allow system_server wifi_data_file:dir create_dir_perms;
allow system_server wifi_data_file:file create_file_perms;
# Manage /data/misc/zoneinfo.
allow system_server zoneinfo_data_file:dir create_dir_perms;
allow system_server zoneinfo_data_file:file create_file_perms;
# Walk /data/data subdirectories.
# Types extracted from seapp_contexts type= fields.
allow system_server { system_app_data_file bluetooth_data_file nfc_data_file radio_data_file shell_data_file app_data_file }:dir { getattr read search };
# Also permit for unlabeled /data/data subdirectories and
# for unlabeled asec containers on upgrades from 4.2.
allow system_server unlabeled:dir r_dir_perms;
# Read pkg.apk file before it has been relabeled by vold.
allow system_server unlabeled:file r_file_perms;
# Populate com.android.providers.settings/databases/settings.db.
allow system_server system_app_data_file:dir create_dir_perms;
allow system_server system_app_data_file:file create_file_perms;
# Receive and use open app data files passed over binder IPC.
# Types extracted from seapp_contexts type= fields.
allow system_server { system_app_data_file bluetooth_data_file nfc_data_file radio_data_file shell_data_file app_data_file }:file { getattr read write append };
# Access to /data/media for measuring disk usage.
allow system_server media_rw_data_file:dir { search getattr open read };
# Receive and use open /data/media files passed over binder IPC.
# Also used for measuring disk usage.
allow system_server media_rw_data_file:file { getattr read write append };
# Relabel apk files.
allow system_server { apk_tmp_file apk_private_tmp_file }:{ dir file } { relabelfrom relabelto };
allow system_server { apk_data_file apk_private_data_file }:{ dir file } { relabelfrom relabelto };
# Relabel wallpaper.
allow system_server system_data_file:file relabelfrom;
allow system_server wallpaper_file:file relabelto;
allow system_server wallpaper_file:file { rw_file_perms rename unlink };
# Backup of wallpaper imagery uses temporary hard links to avoid data churn
allow system_server { system_data_file wallpaper_file }:file link;
# ShortcutManager icons
allow system_server system_data_file:dir relabelfrom;
allow system_server shortcut_manager_icons:dir { create_dir_perms relabelto };
allow system_server shortcut_manager_icons:file create_file_perms;
# Manage ringtones.
allow system_server ringtone_file:dir { create_dir_perms relabelto };
allow system_server ringtone_file:file create_file_perms;
# Relabel icon file.
allow system_server icon_file:file relabelto;
allow system_server icon_file:file { rw_file_perms unlink };
# FingerprintService.java does a restorecon of the directory /data/system/users/[0-9]+/fpdata(/.*)?
allow system_server system_data_file:dir relabelfrom;
# Property Service write
set_prop(system_server, system_prop)
set_prop(system_server, safemode_prop)
set_prop(system_server, dhcp_prop)
set_prop(system_server, net_radio_prop)
set_prop(system_server, net_dns_prop)
set_prop(system_server, system_radio_prop)
set_prop(system_server, debug_prop)
set_prop(system_server, powerctl_prop)
set_prop(system_server, fingerprint_prop)
set_prop(system_server, device_logging_prop)
set_prop(system_server, dumpstate_options_prop)
set_prop(system_server, overlay_prop)
userdebug_or_eng(`set_prop(system_server, wifi_log_prop)')
# ctl interface
set_prop(system_server, ctl_default_prop)
set_prop(system_server, ctl_bugreport_prop)
# cppreopt property
set_prop(system_server, cppreopt_prop)
# Collect metrics on boot time created by init
get_prop(system_server, boottime_prop)
# Read device's serial number from system properties
get_prop(system_server, serialno_prop)
# Read/write the property which keeps track of whether this is the first start of system_server
set_prop(system_server, firstboot_prop)
# Create a socket for receiving info from wpa.
allow system_server wpa_socket:dir rw_dir_perms;
allow system_server system_wpa_socket:sock_file create_file_perms;
# Remove sockets created by wpa_supplicant
allow system_server wpa_socket:sock_file unlink;
# Create a socket for connections from debuggerd.
allow system_server system_ndebug_socket:sock_file create_file_perms;
# Manage cache files.
allow system_server { cache_file cache_recovery_file }:dir { relabelfrom create_dir_perms };
allow system_server { cache_file cache_recovery_file }:file { relabelfrom create_file_perms };
allow system_server { cache_file cache_recovery_file }:fifo_file create_file_perms;
allow system_server system_file:dir r_dir_perms;
allow system_server system_file:lnk_file r_file_perms;
# LocationManager(e.g, GPS) needs to read and write
# to uart driver and ctrl proc entry
allow system_server gps_control:file rw_file_perms;
# Allow system_server to use app-created sockets and pipes.
allow system_server appdomain:{ tcp_socket udp_socket } { getattr getopt setopt read write shutdown };
allow system_server appdomain:{ fifo_file unix_stream_socket } { getattr read write };
# Allow abstract socket connection
allow system_server rild:unix_stream_socket connectto;
# BackupManagerService needs to manipulate backup data files
allow system_server cache_backup_file:dir rw_dir_perms;
allow system_server cache_backup_file:file create_file_perms;
# LocalTransport works inside /cache/backup
allow system_server cache_private_backup_file:dir create_dir_perms;
allow system_server cache_private_backup_file:file create_file_perms;
# Allow system to talk to usb device
allow system_server usb_device:chr_file rw_file_perms;
allow system_server usb_device:dir r_dir_perms;
# Allow system to talk to sensors
allow system_server sensors_device:chr_file rw_file_perms;
# Read from HW RNG (needed by EntropyMixer).
allow system_server hw_random_device:chr_file r_file_perms;
# Read and delete files under /dev/fscklogs.
r_dir_file(system_server, fscklogs)
allow system_server fscklogs:dir { write remove_name };
allow system_server fscklogs:file unlink;
# logd access, system_server inherit logd write socket
# (urge is to deprecate this long term)
allow system_server zygote:unix_dgram_socket write;
# Read from log daemon.
read_logd(system_server)
read_runtime_log_tags(system_server)
# Be consistent with DAC permissions. Allow system_server to write to
# /sys/module/lowmemorykiller/parameters/adj
# /sys/module/lowmemorykiller/parameters/minfree
allow system_server sysfs_lowmemorykiller:file { getattr w_file_perms };
# Read /sys/fs/pstore/console-ramoops
# Don't worry about overly broad permissions for now, as there's
# only one file in /sys/fs/pstore
allow system_server pstorefs:dir r_dir_perms;
allow system_server pstorefs:file r_file_perms;
# /sys access
allow system_server sysfs_zram:dir search;
allow system_server sysfs_zram:file r_file_perms;
add_service(system_server, system_server_service);
allow system_server audioserver_service:service_manager find;
allow system_server batteryproperties_service:service_manager find;
allow system_server cameraserver_service:service_manager find;
allow system_server drmserver_service:service_manager find;
allow system_server dumpstate_service:service_manager find;
allow system_server fingerprintd_service:service_manager find;
allow system_server hal_fingerprint_service:service_manager find;
allow system_server gatekeeper_service:service_manager find;
allow system_server incident_service:service_manager find;
allow system_server installd_service:service_manager find;
allow system_server keystore_service:service_manager find;
allow system_server mediaserver_service:service_manager find;
allow system_server mediametrics_service:service_manager find;
allow system_server mediaextractor_service:service_manager find;
allow system_server mediacodec_service:service_manager find;
allow system_server mediadrmserver_service:service_manager find;
allow system_server mediacasserver_service:service_manager find;
allow system_server netd_service:service_manager find;
allow system_server nfc_service:service_manager find;
allow system_server radio_service:service_manager find;
allow system_server surfaceflinger_service:service_manager find;
allow system_server wificond_service:service_manager find;
allow system_server keystore:keystore_key {
get_state
get
insert
delete
exist
list
reset
password
lock
unlock
is_empty
sign
verify
grant
duplicate
clear_uid
add_auth
user_changed
};
# Allow system server to search and write to the persistent factory reset
# protection partition. This block device does not get wiped in a factory reset.
allow system_server block_device:dir search;
allow system_server frp_block_device:blk_file rw_file_perms;
# Clean up old cgroups
allow system_server cgroup:dir { remove_name rmdir };
# /oem access
r_dir_file(system_server, oemfs)
# Allow resolving per-user storage symlinks
allow system_server { mnt_user_file storage_file }:dir { getattr search };
allow system_server { mnt_user_file storage_file }:lnk_file { getattr read };
# Allow statfs() on storage devices, which happens fast enough that
# we shouldn't be killed during unsafe removal
allow system_server sdcard_type:dir { getattr search };
# Traverse into expanded storage
allow system_server mnt_expand_file:dir r_dir_perms;
# Allow system process to relabel the fingerprint directory after mkdir
# and delete the directory and files when no longer needed
allow system_server fingerprintd_data_file:dir { r_dir_perms remove_name rmdir relabelto write };
allow system_server fingerprintd_data_file:file { getattr unlink };
# Allow system process to read network MAC address
allow system_server sysfs_mac_address:file r_file_perms;
userdebug_or_eng(`
# Allow system server to create and write method traces in /data/misc/trace.
allow system_server method_trace_data_file:dir w_dir_perms;
allow system_server method_trace_data_file:file { create w_file_perms };
# Allow system server to read dmesg
allow system_server kernel:system syslog_read;
')
# For AppFuse.
allow system_server vold:fd use;
allow system_server fuse_device:chr_file { read write ioctl getattr };
allow system_server app_fuse_file:dir rw_dir_perms;
allow system_server app_fuse_file:file { read write open getattr append };
# For configuring sdcardfs
allow system_server configfs:dir { create_dir_perms };
allow system_server configfs:file { getattr open unlink write };
# Connect to adbd and use a socket transferred from it.
# Used for e.g. jdwp.
allow system_server adbd:unix_stream_socket connectto;
allow system_server adbd:fd use;
allow system_server adbd:unix_stream_socket { getattr getopt ioctl read write shutdown };
# Allow invoking tools like "timeout"
allow system_server toolbox_exec:file rx_file_perms;
# Postinstall
#
# For OTA dexopt, allow calls coming from postinstall.
binder_call(system_server, postinstall)
allow system_server postinstall:fifo_file write;
allow system_server update_engine:fd use;
allow system_server update_engine:fifo_file write;
# Access to /data/preloads
allow system_server preloads_data_file:file { r_file_perms unlink };
allow system_server preloads_data_file:dir { r_dir_perms write remove_name rmdir };
r_dir_file(system_server, cgroup)
allow system_server ion_device:chr_file r_file_perms;
allow system_server hal_graphics_allocator:fd use;
r_dir_file(system_server, proc)
r_dir_file(system_server, proc_meminfo)
r_dir_file(system_server, proc_net)
r_dir_file(system_server, rootfs)
r_dir_file(system_server, sysfs_type)
# Allow system_server to make binder calls to hwservicemanager
binder_call(system_server, hwservicemanager)
### Rules needed when Light HAL runs inside system_server process.
### These rules should eventually be granted only when needed.
allow system_server sysfs_leds:lnk_file read;
allow system_server sysfs_leds:file rw_file_perms;
allow system_server sysfs_leds:dir r_dir_perms;
###
# Allow WifiService to start, stop, and read wifi-specific trace events.
allow system_server debugfs_tracing_instances:dir search;
allow system_server debugfs_wifi_tracing:file rw_file_perms;
###
### Neverallow rules
###
### system_server should NEVER do any of this
# Do not allow opening files from external storage as unsafe ejection
# could cause the kernel to kill the system_server.
neverallow system_server sdcard_type:dir { open read write };
neverallow system_server sdcard_type:file rw_file_perms;
# system server should never be operating on zygote spawned app data
# files directly. Rather, they should always be passed via a
# file descriptor.
# Types extracted from seapp_contexts type= fields, excluding
# those types that system_server needs to open directly.
neverallow system_server { bluetooth_data_file nfc_data_file shell_data_file app_data_file }:file { open create unlink link };
# Forking and execing is inherently dangerous and racy. See, for
# example, https://www.linuxprogrammingblog.com/threads-and-fork-think-twice-before-using-them
# Prevent the addition of new file execs to stop the problem from
# getting worse. b/28035297
neverallow system_server { file_type -toolbox_exec -logcat_exec }:file execute_no_trans;
# Ensure that system_server doesn't perform any domain transitions other than
# transitioning to the crash_dump domain when a crash occurs.
neverallow system_server { domain -crash_dump }:process transition;
neverallow system_server *:process dyntransition;
# Only allow crash_dump to connect to system_ndebug_socket.
neverallow { domain -init -system_server -crash_dump } system_ndebug_socket:sock_file { open write };
# system_server should never be executing dex2oat. This is either
# a bug (for example, bug 16317188), or represents an attempt by
# system server to dynamically load a dex file, something we do not
# want to allow.
neverallow system_server dex2oat_exec:file no_x_file_perms;
# system_server should never execute or load executable shared libraries
# in /data except for /data/dalvik-cache files.
neverallow system_server {
data_file_type
-dalvikcache_data_file #mapping with PROT_EXEC
}:file no_x_file_perms;
# The only block device system_server should be accessing is
# the frp_block_device. This helps avoid a system_server to root
# escalation by writing to raw block devices.
neverallow system_server { dev_type -frp_block_device }:blk_file no_rw_file_perms;
# system_server should never use JIT functionality
neverallow system_server self:process execmem;
neverallow system_server ashmem_device:chr_file execute;
# TODO: deal with tmpfs_domain pub/priv split properly
neverallow system_server system_server_tmpfs:file execute;
# dexoptanalyzer is currently used only for secondary dex files which
# system_server should never access.
neverallow system_server dexoptanalyzer_exec:file no_x_file_perms;