1# 2# System Server aka system_server spawned by zygote. 3# Most of the framework services run in this process. 4# 5type system_server, domain, domain_deprecated, mlstrustedsubject; 6 7# Define a type for tmpfs-backed ashmem regions. 8tmpfs_domain(system_server) 9 10# For art. 11allow system_server dalvikcache_data_file:file execute; 12allow system_server dalvikcache_data_file:dir r_dir_perms; 13 14# Enable system server to check the foreign dex usage markers. 15# We need search on top level directories so that we can get to the files 16allow system_server user_profile_data_file:dir search; 17allow system_server user_profile_data_file:file getattr; 18allow system_server user_profile_foreign_dex_data_file:dir { add_name open read write search remove_name }; 19allow system_server user_profile_foreign_dex_data_file:file { getattr rename unlink }; 20 21# /data/resource-cache 22allow system_server resourcecache_data_file:file r_file_perms; 23allow system_server resourcecache_data_file:dir r_dir_perms; 24 25# ptrace to processes in the same domain for debugging crashes. 26allow system_server self:process ptrace; 27 28# Child of the zygote. 29allow system_server zygote:fd use; 30allow system_server zygote:process sigchld; 31allow system_server zygote_tmpfs:file read; 32 33# May kill zygote on crashes. 34allow system_server zygote:process sigkill; 35 36# Read /system/bin/app_process. 37allow system_server zygote_exec:file r_file_perms; 38 39# Needed to close the zygote socket, which involves getopt / getattr 40allow system_server zygote:unix_stream_socket { getopt getattr }; 41 42# system server gets network and bluetooth permissions. 43net_domain(system_server) 44bluetooth_domain(system_server) 45 46# These are the capabilities assigned by the zygote to the 47# system server. 48allow system_server self:capability { 49 ipc_lock 50 kill 51 net_admin 52 net_bind_service 53 net_broadcast 54 net_raw 55 sys_boot 56 sys_nice 57 sys_ptrace 58 sys_time 59 sys_tty_config 60}; 61 62wakelock_use(system_server) 63 64# Trigger module auto-load. 65allow system_server kernel:system module_request; 66 67# Use netlink uevent sockets. 68allow system_server self:netlink_kobject_uevent_socket create_socket_perms; 69 70# Use generic netlink sockets. 71allow system_server self:netlink_socket create_socket_perms; 72allow system_server self:netlink_generic_socket create_socket_perms; 73 74# Use generic "sockets" where the address family is not known 75# to the kernel. 76allow system_server self:socket create_socket_perms; 77 78# Set and get routes directly via netlink. 79allow system_server self:netlink_route_socket nlmsg_write; 80 81# Kill apps. 82allow system_server { appdomain autoplay_app }:process { sigkill signal }; 83 84# Set scheduling info for apps. 85allow system_server { appdomain autoplay_app }:process { getsched setsched }; 86allow system_server audioserver:process { getsched setsched }; 87allow system_server cameraserver:process { getsched setsched }; 88allow system_server mediaserver:process { getsched setsched }; 89allow system_server bootanim:process { getsched setsched }; 90 91# Read /proc/pid data for all domains. This is used by ProcessCpuTracker 92# within system_server to keep track of memory and CPU usage for 93# all processes on the device. In addition, /proc/pid files access is needed 94# for dumping stack traces of native processes. 95r_dir_file(system_server, domain) 96 97# Read/Write to /proc/net/xt_qtaguid/ctrl and and /dev/xt_qtaguid. 98allow system_server qtaguid_proc:file rw_file_perms; 99allow system_server qtaguid_device:chr_file rw_file_perms; 100 101# Read /proc/uid_cputime/show_uid_stat. 102allow system_server proc_uid_cputime_showstat:file r_file_perms; 103 104# Write /proc/uid_cputime/remove_uid_range. 105allow system_server proc_uid_cputime_removeuid:file { w_file_perms getattr }; 106 107# Write to /proc/sysrq-trigger. 108allow system_server proc_sysrq:file rw_file_perms; 109 110# Read /sys/kernel/debug/wakeup_sources. 111allow system_server debugfs:file r_file_perms; 112 113# The DhcpClient and WifiWatchdog use packet_sockets 114allow system_server self:packet_socket create_socket_perms; 115 116# NetworkDiagnostics requires explicit bind() calls to ping sockets. These aren't actually the same 117# as raw sockets, but the kernel doesn't yet distinguish between the two. 118allow system_server node:rawip_socket node_bind; 119 120# 3rd party VPN clients require a tun_socket to be created 121allow system_server self:tun_socket create_socket_perms; 122 123# Notify init of death. 124allow system_server init:process sigchld; 125 126# Talk to init and various daemons via sockets. 127unix_socket_connect(system_server, installd, installd) 128unix_socket_connect(system_server, lmkd, lmkd) 129unix_socket_connect(system_server, mtpd, mtp) 130unix_socket_connect(system_server, netd, netd) 131unix_socket_connect(system_server, vold, vold) 132unix_socket_connect(system_server, zygote, zygote) 133unix_socket_connect(system_server, gps, gpsd) 134unix_socket_connect(system_server, racoon, racoon) 135unix_socket_send(system_server, wpa, wpa) 136unix_socket_connect(system_server, uncrypt, uncrypt) 137 138# Communicate over a socket created by surfaceflinger. 139allow system_server surfaceflinger:unix_stream_socket { read write setopt }; 140 141# Perform Binder IPC. 142binder_use(system_server) 143binder_call(system_server, binderservicedomain) 144binder_call(system_server, gatekeeperd) 145binder_call(system_server, fingerprintd) 146binder_call(system_server, { appdomain autoplay_app }) 147binder_call(system_server, dumpstate) 148binder_call(system_server, netd) 149binder_service(system_server) 150 151# Ask debuggerd to dump backtraces for native stacks of interest. 152# 153# This is derived from the list that system server defines as interesting native processes 154# to dump during ANRs or watchdog aborts, defined in NATIVE_STACKS_OF_INTEREST in 155# frameworks/base/services/core/java/com/android/server/Watchdog.java. 156allow system_server { 157 audioserver 158 bluetooth 159 cameraserver 160 drmserver 161 inputflinger 162 mediacodec 163 mediadrmserver 164 mediaextractor 165 mediaserver 166 sdcardd 167 surfaceflinger 168}:debuggerd dump_backtrace; 169 170# Use sockets received over binder from various services. 171allow system_server audioserver:tcp_socket rw_socket_perms; 172allow system_server audioserver:udp_socket rw_socket_perms; 173allow system_server mediaserver:tcp_socket rw_socket_perms; 174allow system_server mediaserver:udp_socket rw_socket_perms; 175 176# Use sockets received over binder from various services. 177allow system_server mediadrmserver:tcp_socket rw_socket_perms; 178allow system_server mediadrmserver:udp_socket rw_socket_perms; 179 180# Check SELinux permissions. 181selinux_check_access(system_server) 182 183# XXX Label sysfs files with a specific type? 184allow system_server sysfs:file rw_file_perms; 185allow system_server sysfs_nfc_power_writable:file rw_file_perms; 186allow system_server sysfs_devices_system_cpu:file w_file_perms; 187allow system_server sysfs_mac_address:file r_file_perms; 188allow system_server sysfs_thermal:dir search; 189allow system_server sysfs_thermal:file r_file_perms; 190 191# TODO: added to match above sysfs rule. Remove me? 192allow system_server sysfs_usb:file w_file_perms; 193 194# Access devices. 195allow system_server device:dir r_dir_perms; 196allow system_server mdns_socket:sock_file rw_file_perms; 197allow system_server alarm_device:chr_file rw_file_perms; 198allow system_server gpu_device:chr_file rw_file_perms; 199allow system_server iio_device:chr_file rw_file_perms; 200allow system_server input_device:dir r_dir_perms; 201allow system_server input_device:chr_file rw_file_perms; 202allow system_server radio_device:chr_file r_file_perms; 203allow system_server tty_device:chr_file rw_file_perms; 204allow system_server usbaccessory_device:chr_file rw_file_perms; 205allow system_server video_device:dir r_dir_perms; 206allow system_server video_device:chr_file rw_file_perms; 207allow system_server adbd_socket:sock_file rw_file_perms; 208allow system_server rtc_device:chr_file rw_file_perms; 209allow system_server audio_device:dir r_dir_perms; 210 211# write access needed for MIDI 212allow system_server audio_device:chr_file rw_file_perms; 213 214# tun device used for 3rd party vpn apps 215allow system_server tun_device:chr_file rw_file_perms; 216 217# Manage system data files. 218allow system_server system_data_file:dir create_dir_perms; 219allow system_server system_data_file:notdevfile_class_set create_file_perms; 220allow system_server keychain_data_file:dir create_dir_perms; 221allow system_server keychain_data_file:file create_file_perms; 222 223# Manage /data/app. 224allow system_server apk_data_file:dir create_dir_perms; 225allow system_server apk_data_file:file { create_file_perms link }; 226allow system_server apk_tmp_file:dir create_dir_perms; 227allow system_server apk_tmp_file:file create_file_perms; 228 229# Manage /data/app-private. 230allow system_server apk_private_data_file:dir create_dir_perms; 231allow system_server apk_private_data_file:file create_file_perms; 232allow system_server apk_private_tmp_file:dir create_dir_perms; 233allow system_server apk_private_tmp_file:file create_file_perms; 234 235# Manage files within asec containers. 236allow system_server asec_apk_file:dir create_dir_perms; 237allow system_server asec_apk_file:file create_file_perms; 238allow system_server asec_public_file:file create_file_perms; 239 240# Manage /data/anr. 241allow system_server anr_data_file:dir create_dir_perms; 242allow system_server anr_data_file:file create_file_perms; 243 244# Manage /data/backup. 245allow system_server backup_data_file:dir create_dir_perms; 246allow system_server backup_data_file:file create_file_perms; 247 248# Write to /data/system/heapdump 249allow system_server heapdump_data_file:dir rw_dir_perms; 250allow system_server heapdump_data_file:file create_file_perms; 251 252# Manage /data/misc/adb. 253allow system_server adb_keys_file:dir create_dir_perms; 254allow system_server adb_keys_file:file create_file_perms; 255 256# Manage /data/misc/sms. 257# TODO: Split into a separate type? 258allow system_server radio_data_file:dir create_dir_perms; 259allow system_server radio_data_file:file create_file_perms; 260 261# Manage /data/misc/systemkeys. 262allow system_server systemkeys_data_file:dir create_dir_perms; 263allow system_server systemkeys_data_file:file create_file_perms; 264 265# Access /data/tombstones. 266allow system_server tombstone_data_file:dir r_dir_perms; 267allow system_server tombstone_data_file:file r_file_perms; 268 269# Manage /data/misc/vpn. 270allow system_server vpn_data_file:dir create_dir_perms; 271allow system_server vpn_data_file:file create_file_perms; 272 273# Manage /data/misc/wifi. 274allow system_server wifi_data_file:dir create_dir_perms; 275allow system_server wifi_data_file:file create_file_perms; 276 277# Manage /data/misc/zoneinfo. 278allow system_server zoneinfo_data_file:dir create_dir_perms; 279allow system_server zoneinfo_data_file:file create_file_perms; 280 281# Walk /data/data subdirectories. 282# Types extracted from seapp_contexts type= fields. 283allow system_server { system_app_data_file bluetooth_data_file nfc_data_file radio_data_file shell_data_file app_data_file autoplay_data_file }:dir { getattr read search }; 284# Also permit for unlabeled /data/data subdirectories and 285# for unlabeled asec containers on upgrades from 4.2. 286allow system_server unlabeled:dir r_dir_perms; 287# Read pkg.apk file before it has been relabeled by vold. 288allow system_server unlabeled:file r_file_perms; 289 290# Populate com.android.providers.settings/databases/settings.db. 291allow system_server system_app_data_file:dir create_dir_perms; 292allow system_server system_app_data_file:file create_file_perms; 293 294# Receive and use open app data files passed over binder IPC. 295# Types extracted from seapp_contexts type= fields. 296allow 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 }; 297 298# Receive and use open /data/media files passed over binder IPC. 299allow system_server media_rw_data_file:file { getattr read write }; 300 301# Read /file_contexts and /data/security/file_contexts 302security_access_policy(system_server) 303 304# Relabel apk files. 305allow system_server { apk_tmp_file apk_private_tmp_file }:{ dir file } { relabelfrom relabelto }; 306allow system_server { apk_data_file apk_private_data_file }:{ dir file } { relabelfrom relabelto }; 307 308# Relabel wallpaper. 309allow system_server system_data_file:file relabelfrom; 310allow system_server wallpaper_file:file relabelto; 311allow system_server wallpaper_file:file { rw_file_perms rename unlink }; 312 313# Backup of wallpaper imagery uses temporary hard links to avoid data churn 314allow system_server { system_data_file wallpaper_file }:file link; 315 316# ShortcutManager icons 317allow system_server system_data_file:dir relabelfrom; 318allow system_server shortcut_manager_icons:dir { create_dir_perms relabelto }; 319allow system_server shortcut_manager_icons:file create_file_perms; 320 321# Manage ringtones. 322allow system_server ringtone_file:dir { create_dir_perms relabelto }; 323allow system_server ringtone_file:file create_file_perms; 324 325# Relabel icon file. 326allow system_server icon_file:file relabelto; 327allow system_server icon_file:file { rw_file_perms unlink }; 328 329# FingerprintService.java does a restorecon of the directory /data/system/users/[0-9]+/fpdata(/.*)? 330allow system_server system_data_file:dir relabelfrom; 331 332# Property Service write 333set_prop(system_server, system_prop) 334set_prop(system_server, safemode_prop) 335set_prop(system_server, dhcp_prop) 336set_prop(system_server, net_radio_prop) 337set_prop(system_server, system_radio_prop) 338set_prop(system_server, debug_prop) 339set_prop(system_server, powerctl_prop) 340set_prop(system_server, fingerprint_prop) 341set_prop(system_server, device_logging_prop) 342userdebug_or_eng(`set_prop(system_server, wifi_log_prop)') 343 344# ctl interface 345set_prop(system_server, ctl_default_prop) 346set_prop(system_server, ctl_bugreport_prop) 347 348# cppreopt property 349set_prop(system_server, cppreopt_prop) 350 351# Create a socket for receiving info from wpa. 352type_transition system_server wifi_data_file:sock_file system_wpa_socket; 353type_transition system_server wpa_socket:sock_file system_wpa_socket; 354allow system_server wpa_socket:dir rw_dir_perms; 355allow system_server system_wpa_socket:sock_file create_file_perms; 356 357# Remove sockets created by wpa_supplicant 358allow system_server wpa_socket:sock_file unlink; 359 360# Create a socket for connections from debuggerd. 361type_transition system_server system_data_file:sock_file system_ndebug_socket "ndebugsocket"; 362allow system_server system_ndebug_socket:sock_file create_file_perms; 363 364# Manage cache files. 365allow system_server { cache_file cache_recovery_file }:dir { relabelfrom create_dir_perms }; 366allow system_server { cache_file cache_recovery_file }:file { relabelfrom create_file_perms }; 367allow system_server { cache_file cache_recovery_file }:fifo_file create_file_perms; 368 369# Run system programs, e.g. dexopt. 370allow system_server system_file:file x_file_perms; 371 372# LocationManager(e.g, GPS) needs to read and write 373# to uart driver and ctrl proc entry 374allow system_server gps_device:chr_file rw_file_perms; 375allow system_server gps_control:file rw_file_perms; 376 377# Allow system_server to use app-created sockets and pipes. 378allow system_server { appdomain autoplay_app }:{ tcp_socket udp_socket } { getattr getopt setopt read write shutdown }; 379allow system_server { appdomain autoplay_app }:{ fifo_file unix_stream_socket } { getattr read write }; 380 381# Allow abstract socket connection 382allow system_server rild:unix_stream_socket connectto; 383 384# BackupManagerService needs to manipulate backup data files 385allow system_server cache_backup_file:dir rw_dir_perms; 386allow system_server cache_backup_file:file create_file_perms; 387# LocalTransport works inside /cache/backup 388allow system_server cache_private_backup_file:dir create_dir_perms; 389allow system_server cache_private_backup_file:file create_file_perms; 390 391# Allow system to talk to usb device 392allow system_server usb_device:chr_file rw_file_perms; 393allow system_server usb_device:dir r_dir_perms; 394 395# Allow system to talk to sensors 396allow system_server sensors_device:chr_file rw_file_perms; 397 398# Read from HW RNG (needed by EntropyMixer). 399allow system_server hw_random_device:chr_file r_file_perms; 400 401# Read and delete files under /dev/fscklogs. 402r_dir_file(system_server, fscklogs) 403allow system_server fscklogs:dir { write remove_name }; 404allow system_server fscklogs:file unlink; 405 406# logd access, system_server inherit logd write socket 407# (urge is to deprecate this long term) 408allow system_server zygote:unix_dgram_socket write; 409 410# Read from log daemon. 411read_logd(system_server) 412 413# Be consistent with DAC permissions. Allow system_server to write to 414# /sys/module/lowmemorykiller/parameters/adj 415# /sys/module/lowmemorykiller/parameters/minfree 416allow system_server sysfs_lowmemorykiller:file { getattr w_file_perms }; 417 418# Read /sys/fs/pstore/console-ramoops 419# Don't worry about overly broad permissions for now, as there's 420# only one file in /sys/fs/pstore 421allow system_server pstorefs:dir r_dir_perms; 422allow system_server pstorefs:file r_file_perms; 423 424# /sys access 425allow system_server sysfs_zram:dir search; 426allow system_server sysfs_zram:file r_file_perms; 427 428allow system_server audioserver_service:service_manager find; 429allow system_server cameraserver_service:service_manager find; 430allow system_server drmserver_service:service_manager find; 431allow system_server batteryproperties_service:service_manager find; 432allow system_server keystore_service:service_manager find; 433allow system_server gatekeeper_service:service_manager find; 434allow system_server fingerprintd_service:service_manager find; 435allow system_server mediaserver_service:service_manager find; 436allow system_server mediaextractor_service:service_manager find; 437allow system_server mediacodec_service:service_manager find; 438allow system_server mediadrmserver_service:service_manager find; 439allow system_server netd_service:service_manager find; 440allow system_server nfc_service:service_manager find; 441allow system_server radio_service:service_manager find; 442allow system_server system_server_service:service_manager { add find }; 443allow system_server surfaceflinger_service:service_manager find; 444 445allow system_server keystore:keystore_key { 446 get_state 447 get 448 insert 449 delete 450 exist 451 list 452 reset 453 password 454 lock 455 unlock 456 is_empty 457 sign 458 verify 459 grant 460 duplicate 461 clear_uid 462 add_auth 463 user_changed 464}; 465 466# Allow system server to search and write to the persistent factory reset 467# protection partition. This block device does not get wiped in a factory reset. 468allow system_server block_device:dir search; 469allow system_server frp_block_device:blk_file rw_file_perms; 470 471# Clean up old cgroups 472allow system_server cgroup:dir { remove_name rmdir }; 473 474# /oem access 475r_dir_file(system_server, oemfs) 476 477# Allow resolving per-user storage symlinks 478allow system_server { mnt_user_file storage_file }:dir { getattr search }; 479allow system_server { mnt_user_file storage_file }:lnk_file { getattr read }; 480 481# Allow statfs() on storage devices, which happens fast enough that 482# we shouldn't be killed during unsafe removal 483allow system_server sdcard_type:dir { getattr search }; 484 485# Traverse into expanded storage 486allow system_server mnt_expand_file:dir r_dir_perms; 487 488# Allow system process to relabel the fingerprint directory after mkdir 489# and delete the directory and files when no longer needed 490allow system_server fingerprintd_data_file:dir { r_dir_perms remove_name rmdir relabelto write }; 491allow system_server fingerprintd_data_file:file { getattr unlink }; 492 493# Allow system process to read network MAC address 494allow system_server sysfs_mac_address:file r_file_perms; 495 496userdebug_or_eng(` 497 # Allow system server to create and write method traces in /data/misc/trace. 498 allow system_server method_trace_data_file:dir w_dir_perms; 499 allow system_server method_trace_data_file:file { create w_file_perms }; 500 501 # Allow system server to read dmesg 502 allow system_server kernel:system syslog_read; 503') 504 505# For AppFuse. 506allow system_server vold:fd use; 507allow system_server fuse_device:chr_file { read write ioctl getattr }; 508 509# For configuring sdcardfs 510allow system_server configfs:dir { create_dir_perms }; 511allow system_server configfs:file { getattr open unlink write }; 512 513# Connect to adbd and use a socket transferred from it. 514# Used for e.g. jdwp. 515allow system_server adbd:unix_stream_socket connectto; 516allow system_server adbd:fd use; 517allow system_server adbd:unix_stream_socket { getattr getopt ioctl read write shutdown }; 518 519# Access to /data/media. 520# This should be removed if sdcardfs is modified to alter the secontext for its 521# accesses to the underlying FS. 522allow system_server media_rw_data_file:dir search; 523 524# Allow invoking tools like "timeout" 525allow system_server toolbox_exec:file rx_file_perms; 526 527# Postinstall 528# 529# For OTA dexopt, allow calls coming from postinstall. 530binder_call(system_server, postinstall) 531 532allow system_server postinstall:fifo_file write; 533allow system_server update_engine:fd use; 534allow system_server update_engine:fifo_file write; 535 536# Access to /data/preloads 537allow system_server preloads_data_file:file { r_file_perms unlink }; 538allow system_server preloads_data_file:dir { r_dir_perms write remove_name rmdir }; 539 540### 541### Neverallow rules 542### 543### system_server should NEVER do any of this 544 545# Do not allow opening files from external storage as unsafe ejection 546# could cause the kernel to kill the system_server. 547neverallow system_server sdcard_type:dir { open read write }; 548neverallow system_server sdcard_type:file rw_file_perms; 549 550# system server should never be opening zygote spawned app data 551# files directly. Rather, they should always be passed via a 552# file descriptor. 553# Types extracted from seapp_contexts type= fields, excluding 554# those types that system_server needs to open directly. 555neverallow system_server { bluetooth_data_file nfc_data_file shell_data_file app_data_file }:file open; 556 557# system_server should never be executing dex2oat. This is either 558# a bug (for example, bug 16317188), or represents an attempt by 559# system server to dynamically load a dex file, something we do not 560# want to allow. 561neverallow system_server dex2oat_exec:file no_x_file_perms; 562 563# system_server should never execute anything from /data except for /data/dalvik-cache files. 564neverallow system_server { 565 data_file_type 566 -dalvikcache_data_file #mapping with PROT_EXEC 567}:file no_x_file_perms; 568 569# The only block device system_server should be accessing is 570# the frp_block_device. This helps avoid a system_server to root 571# escalation by writing to raw block devices. 572neverallow system_server { dev_type -frp_block_device }:blk_file no_rw_file_perms; 573 574# system_server should never use JIT functionality 575neverallow system_server self:process execmem; 576neverallow system_server ashmem_device:chr_file execute; 577neverallow system_server system_server_tmpfs:file execute; 578