65317124a0
Various third party apps come with their own binaries that they write out to
their sandbox directories and then execute, e.g.:
audit(1386527439.462:190): avc: denied { execute_no_trans } for pid=1550 comm="Thread-79" path="/data/data/com.cisco.anyconnect.vpn.android.avf/app_bin/busybox" dev="mmcblk0p23" ino=602891 scontext=u:r:untrusted_app:s0:c39,c256 tcontext=u:object_r:app_data_file:s0:c39,c256 tclass=file
While this is not ideal from a security POV, it seems necessary to support for
compatibility with Android today.
Split out the execute-related permissions to a separate allow rule as it
only makes sense for regular files (class file) not other kinds of files
(e.g. fifos, sockets, symlinks), and use the rx_file_perms macro.
Move the rule to untrusted_app only so that we do not permit system apps
to execute files written by untrusted apps.
Change-Id: Ic9bfe80e9b14f2c0be14295c70f23f09691ae66c
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
52 lines
1.9 KiB
Text
52 lines
1.9 KiB
Text
###
|
|
### Untrusted apps.
|
|
###
|
|
### This file defines the rules for untrusted apps. An "untrusted
|
|
### app" is an APP with UID between APP_AID (10000)
|
|
### and AID_ISOLATED_START (99000).
|
|
###
|
|
### untrusted_app includes all the appdomain rules, plus the
|
|
### additional following rules:
|
|
###
|
|
|
|
type untrusted_app, domain;
|
|
permissive untrusted_app;
|
|
app_domain(untrusted_app)
|
|
net_domain(untrusted_app)
|
|
bluetooth_domain(untrusted_app)
|
|
|
|
# Some apps ship with shared libraries and binaries that they write out
|
|
# to their sandbox directory and then execute.
|
|
allow untrusted_app app_data_file:file rx_file_perms;
|
|
|
|
allow untrusted_app tun_device:chr_file rw_file_perms;
|
|
|
|
# Internal SDCard rw access.
|
|
allow untrusted_app sdcard_internal:dir create_dir_perms;
|
|
allow untrusted_app sdcard_internal:file create_file_perms;
|
|
|
|
# External SDCard rw access.
|
|
allow untrusted_app sdcard_external:dir create_dir_perms;
|
|
allow untrusted_app sdcard_external:file create_file_perms;
|
|
|
|
# ASEC
|
|
allow untrusted_app asec_apk_file:dir { getattr };
|
|
allow untrusted_app asec_apk_file:file r_file_perms;
|
|
|
|
# Create tcp/udp sockets
|
|
allow untrusted_app node_type:{ tcp_socket udp_socket } node_bind;
|
|
allow untrusted_app self:{ tcp_socket udp_socket } { create_socket_perms accept listen };
|
|
# Bind to a particular hostname/address/interface (e.g., localhost) instead of
|
|
# ANY. Normally, apps should not be listening on all interfaces.
|
|
allow untrusted_app port:{ tcp_socket udp_socket } name_bind;
|
|
|
|
# Allow the allocation and use of ptys
|
|
# Used by: https://play.google.com/store/apps/details?id=jackpal.androidterm
|
|
create_pty(untrusted_app)
|
|
|
|
# Used by Finsky / Android "Verify Apps" functionality when
|
|
# running "adb install foo.apk".
|
|
# TODO: Long term, we don't want apps probing into shell data files.
|
|
# Figure out a way to remove these rules.
|
|
allow untrusted_app shell_data_file:file r_file_perms;
|
|
allow untrusted_app shell_data_file:dir r_dir_perms;
|