public/mediaextractor.te

# mediaextractor - multimedia daemon
type mediaextractor, domain;
type mediaextractor_exec, exec_type, file_type;

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)

r_dir_file(mediaextractor, cgroup)
allow mediaextractor proc_meminfo:file r_file_perms;

crash_dump_fallback(mediaextractor)

# allow mediaextractor read permissions for file sources
allow mediaextractor media_rw_data_file:file { getattr read };
allow mediaextractor app_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 };

###
### 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:{ tcp_socket udp_socket rawip_socket } *;