platform_system_sepolicy/private/mediaextractor.te
Inseob Kim 75806ef3c5 Minimize public policy
Ideally, public should only contain APIs (types / attributes) for
vendor. The other statements like allow/neverallow/typeattributes are
regarded as implementation detail for platform and should be in private.

Bug: 232023812
Test: m selinux_policy
Test: diff <(git diff --staged | grep "^-" | cut -b2- | sort) \
           <(git diff --staged | grep "^+" | cut -b2- | sort)
Test: remove comments on plat_sepolicy.cil, replace base_typeattr_*
      to base_typeattr and then compare old and new plat_sepolicy.cil
Change-Id: I5e7d2da4465ab0216de6bacdf03077d37f6ffe12
2024-03-28 00:33:46 +00:00

78 lines
3 KiB
Text

typeattribute mediaextractor coredomain;
init_daemon_domain(mediaextractor)
tmpfs_domain(mediaextractor)
allow mediaextractor appdomain_tmpfs:file { getattr map read write };
allow mediaextractor mediaserver_tmpfs:file { getattr map read write };
allow mediaextractor system_server_tmpfs:file { getattr map read write };
get_prop(mediaextractor, device_config_media_native_prop)
get_prop(mediaextractor, device_config_swcodec_native_prop)
typeattribute mediaextractor mlstrustedsubject;
binder_use(mediaextractor)
binder_call(mediaextractor, binderservicedomain)
binder_call(mediaextractor, appdomain)
binder_service(mediaextractor)
add_service(mediaextractor, mediaextractor_service)
allow mediaextractor mediametrics_service:service_manager find;
allow mediaextractor hidl_token_hwservice:hwservice_manager find;
allow mediaextractor system_server:fd use;
hal_client_domain(mediaextractor, hal_cas)
hal_client_domain(mediaextractor, hal_allocator)
r_dir_file(mediaextractor, cgroup)
r_dir_file(mediaextractor, cgroup_v2)
allow mediaextractor proc_meminfo:file r_file_perms;
crash_dump_fallback(mediaextractor)
# allow mediaextractor read permissions for file sources
allow mediaextractor { sdcard_type fuse }:file { getattr read };
allow mediaextractor media_rw_data_file:file { getattr read };
allow mediaextractor { app_data_file privapp_data_file }:file { getattr read };
# Read resources from open apk files passed over Binder
allow mediaextractor apk_data_file:file { read getattr };
allow mediaextractor asec_apk_file:file { read getattr };
allow mediaextractor ringtone_file:file { read getattr };
# overlay package access
allow mediaextractor vendor_overlay_file:file { read map };
# scan extractor library directory to dynamically load extractors
allow mediaextractor system_file:dir { read open };
###
### neverallow rules
###
# mediaextractor should never execute any executable without a
# domain transition
neverallow mediaextractor { file_type fs_type }:file execute_no_trans;
# The goal of the mediaserver split is to place media processing code into
# restrictive sandboxes with limited responsibilities and thus limited
# permissions. Example: Audioserver is only responsible for controlling audio
# hardware and processing audio content. Cameraserver does the same for camera
# hardware/content. Etc.
#
# Media processing code is inherently risky and thus should have limited
# permissions and be isolated from the rest of the system and network.
# Lengthier explanation here:
# https://android-developers.googleblog.com/2016/05/hardening-media-stack.html
neverallow mediaextractor domain:{ udp_socket rawip_socket } *;
neverallow mediaextractor { domain userdebug_or_eng(`-su') }:tcp_socket *;
# mediaextractor should not be opening /data files directly. Any files
# it touches (with a few exceptions) need to be passed to it via a file
# descriptor opened outside the process.
neverallow mediaextractor {
data_file_type
userdebug_or_eng(`-apk_data_file') # for loading media extractor plugins
with_native_coverage(`-method_trace_data_file')
}:file open;