platform_system_sepolicy/public/mediacodec.te
Nick Kralevich 38c12828da Add documentation on neverallow rules
Better document the reasons behind the neverallow for tcp/udp sockets.

Test: policy compiles.
Change-Id: Iee386af3be6fc7495addc9300b5628d0fe61c8e9
2017-02-17 22:37:23 +00:00

44 lines
1.6 KiB
Text

# mediacodec - audio and video codecs live here
type mediacodec, domain;
type mediacodec_exec, exec_type, file_type;
typeattribute mediacodec mlstrustedsubject;
binder_use(mediacodec)
binder_call(mediacodec, binderservicedomain)
binder_call(mediacodec, appdomain)
binder_service(mediacodec)
add_service(mediacodec, mediacodec_service)
allow mediacodec mediametrics_service:service_manager find;
allow mediacodec surfaceflinger_service:service_manager find;
allow mediacodec gpu_device:chr_file rw_file_perms;
allow mediacodec video_device:chr_file rw_file_perms;
allow mediacodec video_device:dir search;
allow mediacodec ion_device:chr_file rw_file_perms;
allow mediacodec hal_graphics_allocator:fd use;
# hidl access
hwbinder_use(mediacodec)
hwallocator_use(mediacodec)
allow mediacodec system_file:dir { open read };
###
### neverallow rules
###
# mediacodec should never execute any executable without a
# domain transition
neverallow mediacodec { 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 mediacodec domain:{ tcp_socket udp_socket rawip_socket } *;