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:file r_file_perms; 36# Execute libs in asec containers. 37allow untrusted_app asec_public_file:file { execute execmod }; 38 39# Allow the allocation and use of ptys 40# Used by: https://play.google.com/store/apps/details?id=jackpal.androidterm 41create_pty(untrusted_app) 42 43# Used by Finsky / Android "Verify Apps" functionality when 44# running "adb install foo.apk". 45# TODO: Long term, we don't want apps probing into shell data files. 46# Figure out a way to remove these rules. 47allow untrusted_app shell_data_file:file r_file_perms; 48allow untrusted_app shell_data_file:dir r_dir_perms; 49 50# b/18504118: Allow reads from /data/anr/traces.txt 51# TODO: We shouldn't be allowing all untrusted_apps to read 52# this file. This is only needed for the GMS feedback agent. 53# See also b/18340553. GMS runs as untrusted_app, and 54# it's too late to change the domain it runs in. 55# This line needs to be deleted. 56allow untrusted_app anr_data_file:file r_file_perms; 57 58# 59# Rules migrated from old app domains coalesced into untrusted_app. 60# This includes what used to be media_app, shared_app, and release_app. 61# 62 63# Access /dev/mtp_usb. 64allow untrusted_app mtp_device:chr_file rw_file_perms; 65 66# Access to /data/media. 67allow untrusted_app media_rw_data_file:dir create_dir_perms; 68allow untrusted_app media_rw_data_file:file create_file_perms; 69 70# Write to /cache. 71allow untrusted_app cache_file:dir create_dir_perms; 72allow untrusted_app cache_file:file create_file_perms; 73 74### 75### neverallow rules 76### 77 78# Receive or send uevent messages. 79neverallow untrusted_app domain:netlink_kobject_uevent_socket *; 80 81# Receive or send generic netlink messages 82neverallow untrusted_app domain:netlink_socket *; 83 84# Too much leaky information in debugfs. It's a security 85# best practice to ensure these files aren't readable. 86neverallow untrusted_app debugfs:file read; 87 88# Do not allow untrusted apps to register services. 89# Only trusted components of Android should be registering 90# services. 91neverallow untrusted_app service_manager_type:service_manager add; 92 93# Do not allow untrusted_apps to connect to the property service 94# or set properties. b/10243159 95neverallow untrusted_app property_socket:sock_file write; 96neverallow untrusted_app init:unix_stream_socket connectto; 97neverallow untrusted_app property_type:property_service set; 98 99# Allow verifier to access staged apks. 100allow untrusted_app { apk_tmp_file apk_private_tmp_file }:dir r_dir_perms; 101allow untrusted_app { apk_tmp_file apk_private_tmp_file }:file r_file_perms; 102