android_system_sepolicy/public/hal_drm.te

# HwBinder IPC from client to server, and callbacks
binder_call(hal_drm_client, hal_drm_server)
binder_call(hal_drm_server, hal_drm_client)

hal_attribute_hwservice(hal_drm, hal_drm_hwservice)

allow hal_drm hidl_memory_hwservice:hwservice_manager find;

# Required by Widevine DRM (b/22990512)
allow hal_drm self:process execmem;

# Permit reading device's serial number from system properties
get_prop(hal_drm, serialno_prop)

# Read files already opened under /data
allow hal_drm system_data_file:file { getattr read };

# Read access to pseudo filesystems
r_dir_file(hal_drm, cgroup)
allow hal_drm cgroup:dir { search write };
allow hal_drm cgroup:file w_file_perms;

# Allow access to ion memory allocation device
allow hal_drm ion_device:chr_file rw_file_perms;
allow hal_drm hal_graphics_allocator:fd use;

# Allow access to fds allocated by mediaserver
allow hal_drm mediaserver:fd use;

allow hal_drm sysfs:file r_file_perms;

allow hal_drm tee_device:chr_file rw_file_perms;

allow hal_drm_server { appdomain -isolated_app }:fd use;

# only allow unprivileged socket ioctl commands
allowxperm hal_drm self:{ rawip_socket tcp_socket udp_socket }
  ioctl { unpriv_sock_ioctls unpriv_tty_ioctls };

###
### neverallow rules
###

# hal_drm should never execute any executable without a
# domain transition
neverallow hal_drm_server { file_type fs_type }:file execute_no_trans;

# do not allow privileged socket ioctl commands
neverallowxperm hal_drm_server domain:{ rawip_socket tcp_socket udp_socket } ioctl priv_sock_ioctls;