platform_system_sepolicy/private/ephemeral_app.te
Alex Klyubin 6237d8b787 Start locking down access to services from ephemeral apps
This starts with the reduction in the number of services that
ephemeral apps can access. Prior to this commit, ephemeral apps were
permitted to access most of the service_manager services accessible
by conventional apps. This commit reduces this set by removing access
from ephemeral apps to:
* gatekeeper_service,
* sec_key_att_app_id_provider_service,
* wallpaper_service,
* wifiaware_service,
* wifip2p_service,
* wifi_service.

Test: Device boots up fine, Chrome, Play Movies, YouTube, Netflix, work fine.
Bug: 33349998
Change-Id: Ie4ff0a77eaca8c8c91efda198686c93c3a2bc4b3
2017-03-02 10:23:01 -08:00

54 lines
1.9 KiB
Text

###
### Ephemeral apps.
###
### This file defines the security policy for apps with the ephemeral
### feature.
###
### The ephemeral_app domain is a reduced permissions sandbox allowing
### ephemeral applications to be safely installed and run. Non ephemeral
### applications may also opt-in to ephemeral to take advantage of the
### additional security features.
###
### PackageManager flags an app as ephemeral at install time.
net_domain(ephemeral_app)
app_domain(ephemeral_app)
# Allow ephemeral apps to read/write files in visible storage if provided fds
allow ephemeral_app { sdcard_type media_rw_data_file }:file {read write getattr ioctl lock append};
# services
allow ephemeral_app surfaceflinger_service:service_manager find;
allow ephemeral_app radio_service:service_manager find;
allow ephemeral_app ephemeral_app_api_service:service_manager find;
###
### neverallow rules
###
# Executable content should never be loaded from an ephemeral app home directory.
neverallow ephemeral_app app_data_file:file { execute execute_no_trans };
# Receive or send uevent messages.
neverallow ephemeral_app domain:netlink_kobject_uevent_socket *;
# Receive or send generic netlink messages
neverallow ephemeral_app domain:netlink_socket *;
# Too much leaky information in debugfs. It's a security
# best practice to ensure these files aren't readable.
neverallow ephemeral_app debugfs:file read;
# execute gpu_device
neverallow ephemeral_app gpu_device:chr_file execute;
# access files in /sys with the default sysfs label
neverallow ephemeral_app sysfs:file *;
# Avoid reads from generically labeled /proc files
# Create a more specific label if needed
neverallow ephemeral_app proc:file { no_rw_file_perms no_x_file_perms };
# Directly access external storage
neverallow ephemeral_app { sdcard_type media_rw_data_file }:file {open create};
neverallow ephemeral_app { sdcard_type media_rw_data_file }:dir search;