1### 2### Untrusted apps. 3### 4### This file defines the rules for untrusted apps. 5### Apps are labeled based on mac_permissions.xml (maps signer and 6### optionally package name to seinfo value) and seapp_contexts (maps UID 7### and optionally seinfo value to domain for process and type for data 8### directory). The untrusted_app domain is the default assignment in 9### seapp_contexts for any app with UID between APP_AID (10000) 10### and AID_ISOLATED_START (99000) if the app has no specific seinfo 11### value as determined from mac_permissions.xml. In current AOSP, this 12### domain is assigned to all non-system apps as well as to any system apps 13### that are not signed by the platform key. To move 14### a system app into a specific domain, add a signer entry for it to 15### mac_permissions.xml and assign it one of the pre-existing seinfo values 16### or define and use a new seinfo value in both mac_permissions.xml and 17### seapp_contexts. 18### 19### untrusted_app includes all the appdomain rules, plus the 20### additional following rules: 21### 22 23type untrusted_app, domain; 24app_domain(untrusted_app) 25net_domain(untrusted_app) 26bluetooth_domain(untrusted_app) 27 28# Some apps ship with shared libraries and binaries that they write out 29# to their sandbox directory and then execute. 30allow untrusted_app app_data_file:file { rx_file_perms execmod }; 31 32allow untrusted_app tun_device:chr_file rw_file_perms; 33 34# ASEC 35allow untrusted_app asec_apk_file:dir { getattr }; 36allow untrusted_app asec_apk_file:file r_file_perms; 37# Execute libs in asec containers. 38allow untrusted_app asec_public_file:file { execute execmod }; 39 40# Allow the allocation and use of ptys 41# Used by: https://play.google.com/store/apps/details?id=jackpal.androidterm 42create_pty(untrusted_app) 43 44# Used by Finsky / Android "Verify Apps" functionality when 45# running "adb install foo.apk". 46# TODO: Long term, we don't want apps probing into shell data files. 47# Figure out a way to remove these rules. 48allow untrusted_app shell_data_file:file r_file_perms; 49allow untrusted_app shell_data_file:dir r_dir_perms; 50 51# 52# Rules migrated from old app domains coalesced into untrusted_app. 53# This includes what used to be media_app, shared_app, and release_app. 54# 55 56# Access /dev/mtp_usb. 57allow untrusted_app mtp_device:chr_file rw_file_perms; 58 59# Access to /data/media. 60allow untrusted_app media_rw_data_file:dir create_dir_perms; 61allow untrusted_app media_rw_data_file:file create_file_perms; 62 63# Write to /cache. 64allow untrusted_app cache_file:dir create_dir_perms; 65allow untrusted_app cache_file:file create_file_perms; 66 67### 68### neverallow rules 69### 70 71# Receive or send uevent messages. 72neverallow untrusted_app self:netlink_kobject_uevent_socket *; 73 74# Too much leaky information in debugfs. It's a security 75# best practice to ensure these files aren't readable. 76neverallow untrusted_app debugfs:file read; 77 78# Do not allow untrusted apps to register services. 79# Only trusted components of Android should be registering 80# services. 81neverallow untrusted_app service_manager_type:service_manager add; 82 83# Do not allow untrusted_apps to connect to the property service 84# or set properties. b/10243159 85neverallow untrusted_app property_socket:sock_file write; 86neverallow untrusted_app init:unix_stream_socket connectto; 87neverallow untrusted_app property_type:property_service set; 88 89# Allow verifier to access staged apks. 90allow untrusted_app { apk_tmp_file apk_private_tmp_file }:dir r_dir_perms; 91allow untrusted_app { apk_tmp_file apk_private_tmp_file }:file r_file_perms; 92