Add microdroid specific sepolicy
Microdroid will have a separate sepolicy, apart from the core policy.
This is the first step; For now it's a simple copy of system/sepolicy.
For the future work, it will be stripped.
Bug: 189165759
Test: boot microdroid and see selinux enforced
Change-Id: I2fee39f7231560b49c93bd5e8d0feeffada40938
diff --git a/microdroid/sepolicy/system/public/init.te b/microdroid/sepolicy/system/public/init.te
new file mode 100644
index 0000000..ea5a979
--- /dev/null
+++ b/microdroid/sepolicy/system/public/init.te
@@ -0,0 +1,659 @@
+# init is its own domain.
+type init, domain, mlstrustedsubject;
+type init_exec, system_file_type, exec_type, file_type;
+type init_tmpfs, file_type;
+
+# /dev/__null__ node created by init.
+allow init tmpfs:chr_file { create setattr unlink rw_file_perms };
+
+#
+# init direct restorecon calls.
+#
+# /dev/kmsg
+allow init tmpfs:chr_file relabelfrom;
+allow init kmsg_device:chr_file { getattr write relabelto };
+# /dev/kmsg_debug
+userdebug_or_eng(`
+ allow init kmsg_debug_device:chr_file { open write relabelto };
+')
+
+# allow init to mount and unmount debugfs in debug builds
+userdebug_or_eng(`
+ allow init debugfs:dir mounton;
+')
+
+# /dev/__properties__
+allow init properties_device:dir relabelto;
+allow init properties_serial:file { write relabelto };
+allow init property_type:file { append create getattr map open read relabelto rename setattr unlink write };
+# /dev/__properties__/property_info
+allow init properties_device:file create_file_perms;
+allow init property_info:file relabelto;
+# /dev/event-log-tags
+allow init device:file relabelfrom;
+allow init runtime_event_log_tags_file:file { open write setattr relabelto create };
+# /dev/socket
+allow init { device socket_device dm_user_device }:dir relabelto;
+# allow init to establish connection and communicate with lmkd
+unix_socket_connect(init, lmkd, lmkd)
+# Relabel /dev nodes created in first stage init, /dev/null, /dev/ptmx, /dev/random, /dev/urandom
+allow init { null_device ptmx_device random_device } : chr_file relabelto;
+# /dev/device-mapper, /dev/block(/.*)?
+allow init tmpfs:{ chr_file blk_file } relabelfrom;
+allow init tmpfs:blk_file getattr;
+allow init block_device:{ dir blk_file lnk_file } relabelto;
+allow init dm_device:{ chr_file blk_file } relabelto;
+allow init dm_user_device:chr_file relabelto;
+allow init kernel:fd use;
+# restorecon for early mount device symlinks
+allow init tmpfs:lnk_file { getattr read relabelfrom };
+allow init {
+ metadata_block_device
+ misc_block_device
+ recovery_block_device
+ system_block_device
+ userdata_block_device
+}:{ blk_file lnk_file } relabelto;
+
+allow init super_block_device:lnk_file relabelto;
+
+# Create /mnt/sdcard -> /storage/self/primary symlink.
+allow init mnt_sdcard_file:lnk_file create;
+
+# setrlimit
+allow init self:global_capability_class_set sys_resource;
+
+# Remove /dev/.booting and load /debug_ramdisk/* files
+allow init tmpfs:file { getattr unlink };
+
+# Access pty created for fsck.
+allow init devpts:chr_file { read write open };
+
+# Create /dev/fscklogs files.
+allow init fscklogs:file create_file_perms;
+
+# Access /dev/__null__ node created prior to initial policy load.
+allow init tmpfs:chr_file write;
+
+# Access /dev/console.
+allow init console_device:chr_file rw_file_perms;
+
+# Access /dev/tty0.
+allow init tty_device:chr_file rw_file_perms;
+
+# Call mount(2).
+allow init self:global_capability_class_set sys_admin;
+
+# Call setns(2).
+allow init self:global_capability_class_set sys_chroot;
+
+# Create and mount on directories in /.
+allow init rootfs:dir create_dir_perms;
+allow init {
+ rootfs
+ cache_file
+ cgroup
+ linkerconfig_file
+ storage_file
+ mnt_user_file
+ system_data_file
+ system_data_root_file
+ system_file
+ vendor_file
+ postinstall_mnt_dir
+ mirror_data_file
+}:dir mounton;
+
+# Mount bpf fs on sys/fs/bpf
+allow init fs_bpf:dir mounton;
+
+# Mount on /dev/usb-ffs/adb.
+allow init device:dir mounton;
+
+# Mount tmpfs on /apex
+allow init apex_mnt_dir:dir mounton;
+
+# Bind-mount on /system/apex/com.android.art
+allow init art_apex_dir:dir mounton;
+
+# Create and remove symlinks in /.
+allow init rootfs:lnk_file { create unlink };
+
+# Mount debugfs on /sys/kernel/debug.
+allow init sysfs:dir mounton;
+
+# Create cgroups mount points in tmpfs and mount cgroups on them.
+allow init tmpfs:dir create_dir_perms;
+allow init tmpfs:dir mounton;
+allow init cgroup:dir create_dir_perms;
+allow init cgroup:file rw_file_perms;
+allow init cgroup_rc_file:file rw_file_perms;
+allow init cgroup_desc_file:file r_file_perms;
+allow init cgroup_desc_api_file:file r_file_perms;
+allow init vendor_cgroup_desc_file:file r_file_perms;
+allow init cgroup_v2:dir { mounton create_dir_perms};
+allow init cgroup_v2:file rw_file_perms;
+
+# /config
+allow init configfs:dir mounton;
+allow init configfs:dir create_dir_perms;
+allow init configfs:{ file lnk_file } create_file_perms;
+
+# /metadata
+allow init metadata_file:dir mounton;
+
+# Use tmpfs as /data, used for booting when /data is encrypted
+allow init tmpfs:dir relabelfrom;
+
+# Create directories under /dev/cpuctl after chowning it to system.
+allow init self:global_capability_class_set { dac_override dac_read_search };
+
+# Set system clock.
+allow init self:global_capability_class_set sys_time;
+
+allow init self:global_capability_class_set { sys_rawio mknod };
+
+# Mounting filesystems from block devices.
+allow init dev_type:blk_file r_file_perms;
+allowxperm init dev_type:blk_file ioctl BLKROSET;
+
+# Mounting filesystems.
+# Only allow relabelto for types used in context= mount options,
+# which should all be assigned the contextmount_type attribute.
+# This can be done in device-specific policy via type or typeattribute
+# declarations.
+allow init {
+ fs_type
+ enforce_debugfs_restriction(`-debugfs_type')
+}:filesystem ~relabelto;
+
+# Allow init to mount/unmount debugfs in non-user builds.
+enforce_debugfs_restriction(`
+ userdebug_or_eng(`allow init debugfs_type:filesystem { mount unmount };')
+')
+
+# Allow init to mount tracefs in /sys/kernel/tracing
+allow init debugfs_tracing_debug:filesystem mount;
+
+allow init unlabeled:filesystem ~relabelto;
+allow init contextmount_type:filesystem relabelto;
+
+# Allow read-only access to context= mounted filesystems.
+allow init contextmount_type:dir r_dir_perms;
+allow init contextmount_type:notdevfile_class_set r_file_perms;
+
+# restorecon /adb_keys or any other rootfs files and directories to a more
+# specific type.
+allow init rootfs:{ dir file } relabelfrom;
+
+# mkdir, symlink, write, rm/rmdir, chown/chmod, restorecon/restorecon_recursive from init.rc files.
+# chown/chmod require open+read+setattr required for open()+fchown/fchmod().
+# system/core/init.rc requires at least cache_file and data_file_type.
+# init.<board>.rc files often include device-specific types, so
+# we just allow all file types except /system files here.
+allow init self:global_capability_class_set { chown fowner fsetid };
+
+allow init {
+ file_type
+ -app_data_file
+ -exec_type
+ -misc_logd_file
+ -nativetest_data_file
+ -privapp_data_file
+ -system_app_data_file
+ -system_file_type
+ -vendor_file_type
+}:dir { create search getattr open read setattr ioctl };
+
+allow init {
+ file_type
+ -app_data_file
+ -exec_type
+ -iorapd_data_file
+ -credstore_data_file
+ -keystore_data_file
+ -misc_logd_file
+ -nativetest_data_file
+ -privapp_data_file
+ -shell_data_file
+ -system_app_data_file
+ -system_file_type
+ -vendor_file_type
+ -vold_data_file
+}:dir { write add_name remove_name rmdir relabelfrom };
+
+allow init {
+ file_type
+ -apex_info_file
+ -app_data_file
+ -exec_type
+ -gsi_data_file
+ -iorapd_data_file
+ -credstore_data_file
+ -keystore_data_file
+ -misc_logd_file
+ -nativetest_data_file
+ -privapp_data_file
+ -runtime_event_log_tags_file
+ -shell_data_file
+ -system_app_data_file
+ -system_file_type
+ -vendor_file_type
+ -vold_data_file
+ enforce_debugfs_restriction(`-debugfs_type')
+}:file { create getattr open read write setattr relabelfrom unlink map };
+
+allow init tracefs_type:file { create_file_perms relabelfrom };
+
+allow init {
+ file_type
+ -app_data_file
+ -exec_type
+ -gsi_data_file
+ -iorapd_data_file
+ -credstore_data_file
+ -keystore_data_file
+ -misc_logd_file
+ -nativetest_data_file
+ -privapp_data_file
+ -shell_data_file
+ -system_app_data_file
+ -system_file_type
+ -vendor_file_type
+ -vold_data_file
+}:{ sock_file fifo_file } { create getattr open read setattr relabelfrom unlink };
+
+allow init {
+ file_type
+ -apex_mnt_dir
+ -app_data_file
+ -exec_type
+ -gsi_data_file
+ -iorapd_data_file
+ -credstore_data_file
+ -keystore_data_file
+ -misc_logd_file
+ -nativetest_data_file
+ -privapp_data_file
+ -shell_data_file
+ -system_app_data_file
+ -system_file_type
+ -vendor_file_type
+ -vold_data_file
+}:lnk_file { create getattr setattr relabelfrom unlink };
+
+allow init cache_file:lnk_file r_file_perms;
+
+allow init {
+ file_type
+ -system_file_type
+ -vendor_file_type
+ -exec_type
+ -app_data_file
+ -privapp_data_file
+}:dir_file_class_set relabelto;
+
+allow init { sysfs no_debugfs_restriction(`debugfs') debugfs_tracing debugfs_tracing_debug }:{ dir file lnk_file } { getattr relabelfrom };
+allow init { sysfs_type no_debugfs_restriction(`debugfs_type') tracefs_type }:{ dir file lnk_file } { relabelto getattr };
+allow init dev_type:dir create_dir_perms;
+allow init dev_type:lnk_file create;
+
+# Disable tracing by writing to /sys/kernel/debug/tracing/tracing_on
+allow init debugfs_tracing:file w_file_perms;
+
+# Setup and control wifi event tracing (see wifi-events.rc)
+allow init debugfs_tracing_instances:dir create_dir_perms;
+allow init debugfs_tracing_instances:file w_file_perms;
+allow init debugfs_wifi_tracing:file w_file_perms;
+
+# chown/chmod on pseudo files.
+allow init {
+ fs_type
+ -contextmount_type
+ -keychord_device
+ -proc_type
+ -sdcard_type
+ -sysfs_type
+ -rootfs
+ enforce_debugfs_restriction(`-debugfs_type')
+}:file { open read setattr };
+allow init { fs_type -contextmount_type -sdcard_type -rootfs }:dir { open read setattr search };
+
+allow init {
+ binder_device
+ console_device
+ devpts
+ dm_device
+ hwbinder_device
+ input_device
+ kmsg_device
+ null_device
+ owntty_device
+ pmsg_device
+ ptmx_device
+ random_device
+ tty_device
+ zero_device
+}:chr_file { read open };
+
+# Unlabeled file access for upgrades from 4.2.
+allow init unlabeled:dir { create_dir_perms relabelfrom };
+allow init unlabeled:notdevfile_class_set { create_file_perms relabelfrom };
+
+# Any operation that can modify the kernel ring buffer, e.g. clear
+# or a read that consumes the messages that were read.
+allow init kernel:system syslog_mod;
+allow init self:global_capability2_class_set syslog;
+
+# init access to /proc.
+r_dir_file(init, proc_net_type)
+allow init proc_filesystems:file r_file_perms;
+
+userdebug_or_eng(`
+ # Overlayfs workdir write access check during mount to permit remount,rw
+ allow init overlayfs_file:dir { relabelfrom mounton write };
+ allow init overlayfs_file:file { append };
+ allow init system_block_device:blk_file { write };
+')
+
+allow init {
+ proc # b/67049235 processes /proc/<pid>/* files are mislabeled.
+ proc_bootconfig
+ proc_cmdline
+ proc_diskstats
+ proc_kmsg # Open /proc/kmsg for logd service.
+ proc_meminfo
+ proc_stat # Read /proc/stat for bootchart.
+ proc_uptime
+ proc_version
+}:file r_file_perms;
+
+allow init {
+ proc_abi
+ proc_dirty
+ proc_hostname
+ proc_hung_task
+ proc_extra_free_kbytes
+ proc_net_type
+ proc_max_map_count
+ proc_min_free_order_shift
+ proc_overcommit_memory # /proc/sys/vm/overcommit_memory
+ proc_panic
+ proc_page_cluster
+ proc_perf
+ proc_sched
+ proc_sysrq
+}:file w_file_perms;
+
+allow init {
+ proc_security
+}:file rw_file_perms;
+
+# init chmod/chown access to /proc files.
+allow init {
+ proc_cmdline
+ proc_bootconfig
+ proc_kmsg
+ proc_net
+ proc_pagetypeinfo
+ proc_qtaguid_stat
+ proc_slabinfo
+ proc_sysrq
+ proc_qtaguid_ctrl
+ proc_vmallocinfo
+}:file setattr;
+
+# init access to /sys files.
+allow init {
+ sysfs_android_usb
+ sysfs_dm_verity
+ sysfs_leds
+ sysfs_power
+ sysfs_fs_f2fs
+ sysfs_dm
+}:file w_file_perms;
+
+allow init {
+ sysfs_dt_firmware_android
+ sysfs_fs_ext4_features
+}:file r_file_perms;
+
+allow init {
+ sysfs_zram
+}:file rw_file_perms;
+
+# allow init to create loop devices with /dev/loop-control
+allow init loop_control_device:chr_file rw_file_perms;
+allow init loop_device:blk_file rw_file_perms;
+allowxperm init loop_device:blk_file ioctl {
+ LOOP_SET_FD
+ LOOP_CLR_FD
+ LOOP_CTL_GET_FREE
+ LOOP_SET_BLOCK_SIZE
+ LOOP_SET_DIRECT_IO
+ LOOP_GET_STATUS
+};
+
+# Allow init to write to vibrator/trigger
+allow init sysfs_vibrator:file w_file_perms;
+
+# init chmod/chown access to /sys files.
+allow init {
+ sysfs_android_usb
+ sysfs_devices_system_cpu
+ sysfs_ipv4
+ sysfs_leds
+ sysfs_lowmemorykiller
+ sysfs_power
+ sysfs_vibrator
+ sysfs_wake_lock
+ sysfs_zram
+}:file setattr;
+
+# Set usermodehelpers.
+allow init { usermodehelper sysfs_usermodehelper }:file rw_file_perms;
+
+allow init self:global_capability_class_set net_admin;
+
+# Reboot.
+allow init self:global_capability_class_set sys_boot;
+
+# Init will create /data/misc/logd when the property persist.logd.logpersistd is "logcatd".
+# Init will also walk through the directory as part of a recursive restorecon.
+allow init misc_logd_file:dir { add_name open create read getattr setattr search write };
+allow init misc_logd_file:file { open create getattr setattr write };
+
+# Support "adb shell stop"
+allow init self:global_capability_class_set kill;
+allow init domain:process { getpgid sigkill signal };
+
+# Init creates credstore's directory on boot, and walks through
+# the directory as part of a recursive restorecon.
+allow init credstore_data_file:dir { open create read getattr setattr search };
+allow init credstore_data_file:file { getattr };
+
+# Init creates keystore's directory on boot, and walks through
+# the directory as part of a recursive restorecon.
+allow init keystore_data_file:dir { open create read getattr setattr search };
+allow init keystore_data_file:file { getattr };
+
+# Init creates vold's directory on boot, and walks through
+# the directory as part of a recursive restorecon.
+allow init vold_data_file:dir { open create read getattr setattr search };
+allow init vold_data_file:file { getattr };
+
+# Init creates /data/local/tmp at boot
+allow init shell_data_file:dir { open create read getattr setattr search };
+allow init shell_data_file:file { getattr };
+
+# Set UID, GID, and adjust capability bounding set for services.
+allow init self:global_capability_class_set { setuid setgid setpcap };
+
+# For bootchart to read the /proc/$pid/cmdline file of each process,
+# we need to have following line to allow init to have access
+# to different domains.
+r_dir_file(init, domain)
+
+# Use setexeccon(), setfscreatecon(), and setsockcreatecon().
+# setexec is for services with seclabel options.
+# setfscreate is for labeling directories and socket files.
+# setsockcreate is for labeling local/unix domain sockets.
+allow init self:process { setexec setfscreate setsockcreate };
+
+# Get file context
+allow init file_contexts_file:file r_file_perms;
+
+# sepolicy access
+allow init sepolicy_file:file r_file_perms;
+
+# Perform SELinux access checks on setting properties.
+selinux_check_access(init)
+
+# Ask the kernel for the new context on services to label their sockets.
+allow init kernel:security compute_create;
+
+# Create sockets for the services.
+allow init domain:unix_stream_socket { create bind setopt };
+allow init domain:unix_dgram_socket { create bind setopt };
+
+# Create /data/property and files within it.
+allow init property_data_file:dir create_dir_perms;
+allow init property_data_file:file create_file_perms;
+
+# Set any property.
+allow init property_type:property_service set;
+
+# Send an SELinux userspace denial to the kernel audit subsystem,
+# so it can be picked up and processed by logd. These denials are
+# generated when an attempt to set a property is denied by policy.
+allow init self:netlink_audit_socket { create_socket_perms_no_ioctl nlmsg_relay };
+allow init self:global_capability_class_set audit_write;
+
+# Run "ifup lo" to bring up the localhost interface
+allow init self:udp_socket { create ioctl };
+# in addition to unpriv ioctls granted to all domains, init also needs:
+allowxperm init self:udp_socket ioctl SIOCSIFFLAGS;
+allow init self:global_capability_class_set net_raw;
+
+# Set scheduling info for psi monitor thread.
+# TODO: delete or revise this line b/131761776
+allow init kernel:process { getsched setsched };
+
+# swapon() needs write access to swap device
+# system/core/fs_mgr/fs_mgr.c - fs_mgr_swapon_all
+allow init swap_block_device:blk_file rw_file_perms;
+
+# Create and access /dev files without a specific type,
+# e.g. /dev/.coldboot_done, /dev/.booting
+# TODO: Move these files into their own type unless they are
+# only ever accessed by init.
+allow init device:file create_file_perms;
+
+# keychord retrieval from /dev/input/ devices
+allow init input_device:dir r_dir_perms;
+allow init input_device:chr_file rw_file_perms;
+
+# Access device mapper for setting up dm-verity
+allow init dm_device:chr_file rw_file_perms;
+allow init dm_device:blk_file rw_file_perms;
+
+# Access dm-user for OTA boot
+allow init dm_user_device:chr_file rw_file_perms;
+
+# Access metadata block device for storing dm-verity state
+allow init metadata_block_device:blk_file rw_file_perms;
+
+# Read /sys/fs/pstore/console-ramoops to detect restarts caused
+# by dm-verity detecting corrupted blocks
+allow init pstorefs:dir search;
+allow init pstorefs:file r_file_perms;
+allow init kernel:system syslog_read;
+
+# linux keyring configuration
+allow init init:key { write search setattr };
+
+# Allow init to create /data/unencrypted
+allow init unencrypted_data_file:dir create_dir_perms;
+
+# Set encryption policy on dirs in /data
+allowxperm init { data_file_type unlabeled }:dir ioctl {
+ FS_IOC_GET_ENCRYPTION_POLICY
+ FS_IOC_SET_ENCRYPTION_POLICY
+};
+
+# Raw writes to misc block device
+allow init misc_block_device:blk_file w_file_perms;
+
+r_dir_file(init, system_file)
+r_dir_file(init, vendor_file_type)
+
+allow init system_data_file:file { getattr read };
+allow init system_data_file:lnk_file r_file_perms;
+
+# For init to be able to run shell scripts from vendor
+allow init vendor_shell_exec:file execute;
+
+# Metadata setup
+allow init vold_metadata_file:dir create_dir_perms;
+allow init vold_metadata_file:file getattr;
+allow init metadata_bootstat_file:dir create_dir_perms;
+allow init metadata_bootstat_file:file w_file_perms;
+allow init userspace_reboot_metadata_file:file w_file_perms;
+
+# Allow init to touch PSI monitors
+allow init proc_pressure_mem:file { rw_file_perms setattr };
+
+# init is using bootstrap bionic
+allow init system_bootstrap_lib_file:dir r_dir_perms;
+allow init system_bootstrap_lib_file:file { execute read open getattr map };
+
+# stat the root dir of fuse filesystems (for the mount handler)
+allow init fuse:dir { search getattr };
+
+# allow filesystem tuning
+allow init userdata_sysdev:file create_file_perms;
+
+###
+### neverallow rules
+###
+
+# The init domain is only entered via an exec based transition from the
+# kernel domain, never via setcon().
+neverallow domain init:process dyntransition;
+neverallow { domain -kernel } init:process transition;
+neverallow init { file_type fs_type -init_exec }:file entrypoint;
+
+# Never read/follow symlinks created by shell or untrusted apps.
+neverallow init shell_data_file:lnk_file read;
+neverallow init { app_data_file privapp_data_file }:lnk_file read;
+
+# init should never execute a program without changing to another domain.
+neverallow init { file_type fs_type }:file execute_no_trans;
+
+# The use of sensitive environment variables, such as LD_PRELOAD, is disallowed
+# when init is executing other binaries. The use of LD_PRELOAD for init spawned
+# services is generally considered a no-no, as it injects libraries which the
+# binary was not expecting. This is especially problematic for APEXes. The use
+# of LD_PRELOAD via APEXes is a layering violation, and inappropriately loads
+# code into a process which wasn't expecting that code, with potentially
+# unexpected side effects. (b/140789528)
+neverallow init *:process noatsecure;
+
+# init can never add binder services
+neverallow init service_manager_type:service_manager { add find };
+# init can never list binder services
+neverallow init servicemanager:service_manager list;
+
+# Init should not be creating subdirectories in /data/local/tmp
+neverallow init shell_data_file:dir { write add_name remove_name };
+
+# Init should not access sysfs node that are not explicitly labeled.
+neverallow init sysfs:file { open read write };
+
+# No domain should be allowed to ptrace init.
+neverallow * init:process ptrace;
+
+# init owns the root of /data
+# TODO(b/140259336) We want to remove vendor_init
+# TODO(b/141108496) We want to remove toolbox
+neverallow { domain -init -toolbox -vendor_init -vold } system_data_root_file:dir { write add_name remove_name };