platform_system_sepolicy/public/domain.te

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Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
# Rules for all domains.
# Allow reaping by init.
allow domain init:process sigchld;
# Intra-domain accesses.
allow domain self:process {
fork
sigchld
sigkill
sigstop
signull
signal
getsched
setsched
getsession
getpgid
setpgid
getcap
setcap
getattr
setrlimit
};
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
allow domain self:fd use;
allow domain proc:dir r_dir_perms;
Start the process of locking down proc/net Files in /proc/net leak information. This change is the first step in determining which files apps may use, whitelisting benign access, and otherwise removing access while providing safe alternative APIs. To that end, this change: * Introduces the proc_net_type attribute which will assigned to any new SELinux types in /proc/net to avoid removing access to privileged processes. These processes may be evaluated later, but are lower priority than apps. * Labels /proc/net/{tcp,tcp6,udp,udp6} as proc_net_vpn due to existing use by VPN apps. This may be replaced by an alternative API. * Audits all other proc/net access for apps. * Audits proc/net access for other processes which are currently granted broad read access to /proc/net but should not be including storaged, zygote, clatd, logd, preopt2cachename and vold. Bug: 9496886 Bug: 68016944 Test: Boot Taimen-userdebug. On both wifi and cellular: stream youtube navigate maps, send text message, make voice call, make video call. Verify no avc "granted" messages in the logs. Test: A few VPN apps including "VPN Monster", "Turbo VPN", and "Freighter". Verify no logspam with the current setup. Test: atest CtsNativeNetTestCases Test: atest netd_integration_test Test: atest QtaguidPermissionTest Test: atest FileSystemPermissionTest Change-Id: I7e49f796a25cf68bc698c6c9206e24af3ae11457 Merged-In: I7e49f796a25cf68bc698c6c9206e24af3ae11457 (cherry picked from commit 087318957f26e921d62f2e234fc14bff3c59030e)
2018-04-10 21:47:48 +02:00
allow domain proc_net_type:dir search;
r_dir_file(domain, self)
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
allow domain self:{ fifo_file file } rw_file_perms;
allow domain self:unix_dgram_socket { create_socket_perms sendto };
allow domain self:unix_stream_socket { create_stream_socket_perms connectto };
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
# Inherit or receive open files from others.
allow domain init:fd use;
userdebug_or_eng(`
allow domain su:fd use;
allow domain su:unix_stream_socket { connectto getattr getopt read write shutdown };
allow domain su:unix_dgram_socket sendto;
allow { domain -init } su:binder { call transfer };
Address system_server denials. Label /proc/sysrq-trigger and allow access. Label /dev/socket/mtpd and allow access. Resolves denials such as: avc: denied { getattr } for pid=12114 comm="Binder_2" path="socket:[219779]" dev="sockfs" ino=219779 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { call } for pid=1007 comm="Binder_8" scontext=u:r:system_server:s0 tcontext=u:r:su:s0 tclass=binder avc: denied { write } for pid=1024 comm="watchdog" name="sysrq-trigger" dev="proc" ino=4026533682 scontext=u:r:system_server:s0 tcontext=u:object_r:proc:s0 tclass=file avc: denied { write } for pid=11567 comm="LegacyVpnRunner" name="mtpd" dev="tmpfs" ino=36627 scontext=u:r:system_server:s0 tcontext=u:object_r:socket_device:s0 tclass=sock_file avc: denied { ptrace } for pid=10924 comm=5369676E616C2043617463686572 scontext=u:r:system_server:s0 tcontext=u:r:system_server:s0 tclass=process avc: denied { sigkill } for pid=26077 comm="NativeCrashRepo" scontext=u:r:system_server:s0 tcontext=u:r:zygote:s0 tclass=process avc: denied { write } for pid=1024 comm="android.bg" scontext=u:r:system_server:s0 tcontext=u:r:system_server:s0 tclass=netlink_socket avc: denied { getattr } for pid=473 comm="FinalizerDaemon" path="socket:[11467]" dev="sockfs" ino=11467 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=tcp_socket avc: denied { getattr } for pid=473 comm="FinalizerDaemon" path="socket:[12076]" dev="sockfs" ino=12076 scontext=u:r:system_server:s0 tcontext=u:r:mediaserv er:s0 tclass=udp_socket avc: denied { getopt } for pid=473 comm="FinalizerDaemon" laddr=192.168.159.172 lport=51576 faddr=93.127.173.40 fport=554 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=tcp_socket avc: denied { getopt } for pid=473 comm="FinalizerDaemon" lport=15658 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=udp_socket avc: denied { read write } for pid=21384 comm="rtsp" path="socket:[443742]" dev="sockfs" ino=443742 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s 0 tclass=tcp_socket avc: denied { read write } for pid=21384 comm="rtsp" path="socket:[444842]" dev="sockfs" ino=444842 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=udp_socket avc: denied { setopt } for pid=1326 comm="Binder_9" lport=16216 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=udp_socket avc: denied { setopt } for pid=1676 comm="Binder_6" laddr=192.168.156.130 lport=51044 faddr=74.125.214.81 fport=554 scontext=u:r:system_server:s0 tcontext=u:r:mediaserver:s0 tclass=tcp_socket avc: denied { getattr } for pid=10915 comm="system_server" path="/dev/mdm" dev="tmpfs" ino=7484 scontext=u:r:system_server:s0 tcontext=u:object_r:radio_device:s0 tclass=chr_file avc: denied { read } for pid=10915 comm="system_server" name="mdm" dev="tmpfs" ino=7484 scontext=u:r:system_server:s0 tcontext=u:object_r:radio_device:s0 tclass=chr_file avc: denied { unlink } for pid=14866 comm="system_server" name="wallpaper" dev="mmcblk0p9" ino=285715 scontext=u:r:system_server:s0 tcontext=u:object_r:wallpaper_file:s0 tclass=file avc: denied { getattr } for pid=12114 comm="Binder_2" path="socket:[219779]" dev="sockfs" ino=219779 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { getopt } for pid=32300 comm="Binder_1" laddr=::ffff:127.0.0.1 lport=4939 faddr=::ffff:127.0.0.1 fport=53318 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { read write } for pid=10840 comm="pool-17-thread-" path="socket:[205990]" dev="sockfs" ino=205990 scontext=u:r:untrusted_app:s0 tcontext=u:r:system_server:s0 tclass=tcp_socket avc: denied { write } for pid=20817 comm="dumpsys" path="/mnt/shell/emulated/0/aupt-output/bugreport-2014-02-22-11-17-16.txt.tmp" dev="fuse" ino=3100784040 scontext=u:r:system_server:s0 tcontext=u:object_r:sdcard_internal:s0 tclass=file Change-Id: I481ac26667b487031a5d3317b0a028a027a8e641 Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
2014-03-05 15:50:08 +01:00
# Running something like "pm dump com.android.bluetooth" requires
# fifo writes
allow domain su:fifo_file { write getattr };
# allow "gdbserver --attach" to work for su.
allow domain su:process sigchld;
# Allow writing coredumps to /cores/*
allow domain coredump_file:file create_file_perms;
allow domain coredump_file:dir ra_dir_perms;
')
with_native_coverage(`
# Allow writing coverage information to /data/misc/trace
allow domain method_trace_data_file:dir create_dir_perms;
allow domain method_trace_data_file:file create_file_perms;
')
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
# Root fs.
allow domain tmpfs:dir { getattr search };
allow domain rootfs:dir search;
allow domain rootfs:lnk_file { read getattr };
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
# Device accesses.
allow domain device:dir search;
allow domain dev_type:lnk_file r_file_perms;
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
allow domain devpts:dir search;
allow domain socket_device:dir r_dir_perms;
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
allow domain owntty_device:chr_file rw_file_perms;
allow domain null_device:chr_file rw_file_perms;
allow domain zero_device:chr_file rw_file_perms;
# /dev/ashmem is being deprecated by means of constraining and eventually
# removing all "open" permissions. We preserve the other permissions.
allow domain ashmem_device:chr_file { getattr read ioctl lock map append write };
# This device is used by libcutils, which is accessible to everyone.
allow domain ashmem_libcutils_device:chr_file rw_file_perms;
# /dev/binder can be accessed by ... everyone! :)
allow { domain -hwservicemanager -vndservicemanager } binder_device:chr_file rw_file_perms;
allow { domain -servicemanager -vndservicemanager -isolated_app } hwbinder_device:chr_file rw_file_perms;
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
allow domain ptmx_device:chr_file rw_file_perms;
allow domain random_device:chr_file rw_file_perms;
2017-11-20 20:02:03 +01:00
allow domain proc_random:dir r_dir_perms;
allow domain proc_random:file r_file_perms;
allow domain properties_device:dir { search getattr };
allow domain properties_serial:file r_file_perms;
allow domain property_info:file r_file_perms;
# Public readable properties
get_prop(domain, debug_prop)
get_prop(domain, exported_config_prop)
get_prop(domain, exported_default_prop)
get_prop(domain, exported_dumpstate_prop)
get_prop(domain, exported_fingerprint_prop)
get_prop(domain, exported_radio_prop)
get_prop(domain, exported_secure_prop)
get_prop(domain, exported_system_prop)
get_prop(domain, exported_vold_prop)
get_prop(domain, exported2_default_prop)
get_prop(domain, logd_prop)
limit shell's access to log.* properties Restrict the ability of the shell to set the log.* properties. Namely: only allow the shell to set such properities on eng and userdebug builds. The shell (and other domains) can continue to read log.* properties on all builds. While there: harmonize permissions for log.* and persist.log.tag. Doing so introduces two changes: - log.* is now writable from from |system_app|. This mirrors the behavior of persist.log.tag, which is writable to support "Developer options" -> "Logger buffer sizes" -> "Off". (Since this option is visible on user builds, the permission is enabled for all builds.) - persist.log.tag can now be set from |shell| on userdebug_or_eng(). BUG=28221972 TEST=manual (see below) Testing details - user build (log.tag) $ adb shell setprop log.tag.foo V $ adb shell getprop log.tag <blank line> $ adb bugreport | grep log.tag.foo [ 146.525836] init: avc: denied { set } for property=log.tag.foo pid=4644 uid=2000 gid=2000 scontext=u:r:shell:s0 tcontext=u:object_r:log_prop:s0 tclass=property_service permissive=0 [ 146.525878] init: sys_prop: permission denied uid:2000 name:log.tag.foo - userdebug build (log.tag) $ adb shell getprop log.tag.foo <blank line> $ adb shell setprop log.tag.foo V $ adb shell getprop log.tag.foo V - user build (persist.log.tag) $ adb shell getprop | grep log.tag <no match> - Developer options -> Logger buffer sizes -> Off $ adb shell getprop | grep log.tag [persist.log.tag]: [Settings] [persist.log.tag.snet_event_log]: [I] Change-Id: Idf00e7a623723a7c46bf6d01e386aeca92b2ad75
2016-04-15 20:10:06 +02:00
# Let everyone read log properties, so that liblog can avoid sending unloggable
# messages to logd.
get_prop(domain, log_property_type)
dontaudit domain property_type:file audit_access;
allow domain property_contexts_file:file r_file_perms;
allow domain init:key search;
allow domain vold:key search;
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
# logd access
write_logd(domain)
# Directory/link file access for path resolution.
allow domain {
system_file
system_lib_file
system_seccomp_policy_file
system_security_cacerts_file
}:dir r_dir_perms;
allow domain system_file:lnk_file { getattr read };
Enable SELinux protections for netd. This change does several things: 1) Restore domain.te to the version present at cd516a32663b4eb11b2e3356b86450020e59e279 . This is the version currently being distributed in AOSP. 2) Add "allow domain properties_device:file r_file_perms;" to domain.te, to allow all domains to read /dev/__properties__ . This change was missing from AOSP. 3) Restore netd.te to the version present at 80c9ba5267f1a6ceffcf979471d101948b520ad6 . This is the version currently being distributed in AOSP. 4) Remove anything involving module loading from netd.te. CTS enforces that Android kernels can't have module loading enabled. 5) Add several new capabilities, plus data file rules, to netd.te, since netd needs to write to files owned by wifi. 6) Add a new unconfined domain called dnsmasq.te, and allow transitions from netd to that domain. Over time, we'll tighten up the dnsmasq.te domain. 7) Add a new unconfined domain called hostapd.te, and allow transitions from netd to that domain. Over time, we'll tighten up the hostapd.te domain. The net effect of these changes is to re-enable SELinux protections for netd. The policy is FAR from perfect, and allows a lot of wiggle room, but we can improve it over time. Testing: as much as possible, I've exercised networking related functionality, including turning on and off wifi, entering airplane mode, and enabling tethering and portable wifi hotspots. It's quite possible I've missed something, and if we experience problems, I can roll back this change. Bug: 9618347 Change-Id: I23ff3eebcef629bc7baabcf6962f25f116c4a3c0
2013-06-28 00:11:02 +02:00
# Global access to /system/etc/security/cacerts/*, /system/etc/seccomp_policy/*, /system/lib[64]/*,
# /(system|product|system_ext)/etc/(group|passwd), linker and its config.
allow domain system_seccomp_policy_file:file r_file_perms;
# cacerts are accessible from public Java API.
allow domain system_security_cacerts_file:file r_file_perms;
allow domain system_group_file:file r_file_perms;
allow domain system_passwd_file:file r_file_perms;
allow domain system_linker_exec:file { execute read open getattr map };
allow domain system_linker_config_file:file r_file_perms;
allow domain system_lib_file:file { execute read open getattr map };
# To allow following symlinks at /system/bin/linker, /system/lib/libc.so, etc.
allow domain system_linker_exec:lnk_file { read open getattr };
allow domain system_lib_file:lnk_file { read open getattr };
allow domain system_event_log_tags_file:file r_file_perms;
allow { appdomain coredomain } system_file:file { execute read open getattr map };
# Make sure system/vendor split doesn not affect non-treble
# devices
not_full_treble(`
allow domain system_file:file { execute read open getattr map };
allow domain vendor_file_type:dir { search getattr };
allow domain vendor_file_type:file { execute read open getattr map };
allow domain vendor_file_type:lnk_file { getattr read };
')
# All domains are allowed to open and read directories
# that contain HAL implementations (e.g. passthrough
# HALs require clients to have these permissions)
allow domain vendor_hal_file:dir r_dir_perms;
# Everyone can read and execute all same process HALs
allow domain same_process_hal_file:dir r_dir_perms;
allow {
domain
-coredomain # access is explicitly granted to individual coredomains
} same_process_hal_file:file { execute read open getattr map };
# Any process can load vndk-sp libraries, which are system libraries
# used by same process HALs
allow domain vndk_sp_file:dir r_dir_perms;
allow domain vndk_sp_file:file { execute read open getattr map };
# All domains get access to /vendor/etc
allow domain vendor_configs_file:dir r_dir_perms;
allow domain vendor_configs_file:file { read open getattr map };
full_treble_only(`
# Allow all domains to be able to follow /system/vendor and/or
# /vendor/odm symlinks.
allow domain vendor_file_type:lnk_file { getattr open read };
# This is required to be able to search & read /vendor/lib64
# in order to lookup vendor libraries. The execute permission
# for coredomains is granted *only* for same process HALs
allow domain vendor_file:dir { getattr search };
# Allow reading and executing out of /vendor to all vendor domains
allow { domain -coredomain } vendor_file_type:dir r_dir_perms;
allow { domain -coredomain } vendor_file_type:file { read open getattr execute map };
allow { domain -coredomain } vendor_file_type:lnk_file { getattr read };
')
# read and stat any sysfs symlinks
allow domain sysfs:lnk_file { getattr read };
# libc references /data/misc/zoneinfo and /system/usr/share/zoneinfo for
# timezone related information.
# This directory is considered to be a VNDK-stable
allow domain { system_zoneinfo_file zoneinfo_data_file }:file r_file_perms;
allow domain { system_zoneinfo_file zoneinfo_data_file }:dir r_dir_perms;
# Lots of processes access current CPU information
r_dir_file(domain, sysfs_devices_system_cpu)
r_dir_file(domain, sysfs_usb);
# If kernel CONFIG_TRANSPARENT_HUGEPAGE is enabled, libjemalloc5 (statically
# included by libc) reads /sys/kernel/mm/transparent_hugepage/enabled.
allow domain sysfs_transparent_hugepage:dir search;
allow domain sysfs_transparent_hugepage:file r_file_perms;
# files under /data.
not_full_treble(`
allow domain system_data_file:dir getattr;
')
allow { coredomain appdomain } system_data_file:dir getattr;
# /data has the label system_data_root_file. Vendor components need the search
# permission on system_data_root_file for path traversal to /data/vendor.
allow domain system_data_root_file:dir { search getattr } ;
allow domain system_data_file:dir search;
# TODO restrict this to non-coredomain
allow domain vendor_data_file:dir { getattr search };
# required by the dynamic linker
allow domain proc:lnk_file { getattr read };
# /proc/cpuinfo
allow domain proc_cpuinfo:file r_file_perms;
# /dev/cpu_variant:.*
allow domain dev_cpu_variant:file r_file_perms;
# profiling needs to read /proc/sys/kernel/perf_event_max_sample_rate
allow domain proc_perf:file r_file_perms;
# toybox loads libselinux which stats /sys/fs/selinux/
allow domain selinuxfs:dir search;
allow domain selinuxfs:file getattr;
allow domain sysfs:dir search;
allow domain selinuxfs:filesystem getattr;
# Almost all processes log tracing information to
# /sys/kernel/debug/tracing/trace_marker
# The reason behind this is documented in b/6513400
allow domain debugfs:dir search;
allow domain debugfs_tracing:dir search;
allow domain debugfs_tracing_debug:dir search;
allow domain debugfs_trace_marker:file w_file_perms;
# Filesystem access.
allow domain fs_type:filesystem getattr;
allow domain fs_type:dir getattr;
# Restrict all domains to a whitelist for common socket types. Additional
# ioctl commands may be added to individual domains, but this sets safe
# defaults for all processes. Note that granting this whitelist to domain does
# not grant the ioctl permission on these socket types. That must be granted
# separately.
allowxperm domain domain:{ icmp_socket rawip_socket tcp_socket udp_socket }
ioctl { unpriv_sock_ioctls unpriv_tty_ioctls };
# default whitelist for unix sockets.
allowxperm domain { domain pdx_channel_socket_type }:{ unix_dgram_socket unix_stream_socket }
ioctl unpriv_unix_sock_ioctls;
# Restrict PTYs to only whitelisted ioctls.
# Note that granting this whitelist to domain does
# not grant the wider ioctl permission. That must be granted
# separately.
allowxperm domain devpts:chr_file ioctl unpriv_tty_ioctls;
# All domains must clearly enumerate what ioctls they use
# on filesystem objects (plain files, directories, symbolic links,
# named pipes, and named sockets). We start off with a safe set.
allowxperm domain { file_type fs_type domain dev_type }:{ dir notdevfile_class_set blk_file } ioctl { FIOCLEX FIONCLEX };
# If a domain has ioctl access to tun_device, it must clearly enumerate the
# ioctls used. Safe defaults are listed below.
allowxperm domain tun_device:chr_file ioctl { FIOCLEX FIONCLEX };
Allow more file ioctls The shell script interpreter checks if file descriptors are ttys, which causes a bunch of denials. Allow the benign ioctl TCGETS. Addresses the following denials: type=1400 audit(0.0:321): avc: denied { ioctl } for comm="sh" path="/data/misc/perfprofd/perferr.txt" dev="sda13" ino=6817306 ioctlcmd=5401 scontext=u:r:perfprofd:s0 tcontext=u:object_r:perfprofd_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3189): avc: denied { ioctl } for comm="ps" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3004): avc: denied { ioctl } for comm="top" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 Include the virtual sdcard when allowing F2FS specific sqlite ioctls, since apps write sqlite files to the virtual sdcard. Addresses the following denials: type=1400 audit(0.0:324): avc: denied { ioctl } for comm="amapLocManagerT" path="/storage/emulated/0/amap/openamaplocationsdk/alsn20170807.db" dev="sdcardfs" ino=3546650 ioctlcmd=f50c scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:sdcardfs:s0 tclass=file permissive=0 app=com.xiaomi.hm.health Test: policy compiles. Change-Id: I7fc570f2bbf69485b1ee6e6b2d9a421639d29123
2018-10-12 21:44:33 +02:00
# Allow a process to make a determination whether a file descriptor
# for a plain file or pipe (fifo_file) is a tty. Note that granting
# this whitelist to domain does not grant the ioctl permission to
# these files. That must be granted separately.
Allow more file ioctls The shell script interpreter checks if file descriptors are ttys, which causes a bunch of denials. Allow the benign ioctl TCGETS. Addresses the following denials: type=1400 audit(0.0:321): avc: denied { ioctl } for comm="sh" path="/data/misc/perfprofd/perferr.txt" dev="sda13" ino=6817306 ioctlcmd=5401 scontext=u:r:perfprofd:s0 tcontext=u:object_r:perfprofd_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3189): avc: denied { ioctl } for comm="ps" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3004): avc: denied { ioctl } for comm="top" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 Include the virtual sdcard when allowing F2FS specific sqlite ioctls, since apps write sqlite files to the virtual sdcard. Addresses the following denials: type=1400 audit(0.0:324): avc: denied { ioctl } for comm="amapLocManagerT" path="/storage/emulated/0/amap/openamaplocationsdk/alsn20170807.db" dev="sdcardfs" ino=3546650 ioctlcmd=f50c scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:sdcardfs:s0 tclass=file permissive=0 app=com.xiaomi.hm.health Test: policy compiles. Change-Id: I7fc570f2bbf69485b1ee6e6b2d9a421639d29123
2018-10-12 21:44:33 +02:00
allowxperm domain { file_type fs_type }:file ioctl { TCGETS };
allowxperm domain domain:fifo_file ioctl { TCGETS };
Allow more file ioctls The shell script interpreter checks if file descriptors are ttys, which causes a bunch of denials. Allow the benign ioctl TCGETS. Addresses the following denials: type=1400 audit(0.0:321): avc: denied { ioctl } for comm="sh" path="/data/misc/perfprofd/perferr.txt" dev="sda13" ino=6817306 ioctlcmd=5401 scontext=u:r:perfprofd:s0 tcontext=u:object_r:perfprofd_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3189): avc: denied { ioctl } for comm="ps" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3004): avc: denied { ioctl } for comm="top" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 Include the virtual sdcard when allowing F2FS specific sqlite ioctls, since apps write sqlite files to the virtual sdcard. Addresses the following denials: type=1400 audit(0.0:324): avc: denied { ioctl } for comm="amapLocManagerT" path="/storage/emulated/0/amap/openamaplocationsdk/alsn20170807.db" dev="sdcardfs" ino=3546650 ioctlcmd=f50c scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:sdcardfs:s0 tclass=file permissive=0 app=com.xiaomi.hm.health Test: policy compiles. Change-Id: I7fc570f2bbf69485b1ee6e6b2d9a421639d29123
2018-10-12 21:44:33 +02:00
# If a domain has access to perform an ioctl on a block device, allow these
# very common, benign ioctls
allowxperm domain dev_type:blk_file ioctl { BLKGETSIZE64 BLKSSZGET };
# Support sqlite F2FS specific optimizations
# ioctl permission on the specific file type is still required
# TODO: consider only compiling these rules if we know the
# /data partition is F2FS
Allow more file ioctls The shell script interpreter checks if file descriptors are ttys, which causes a bunch of denials. Allow the benign ioctl TCGETS. Addresses the following denials: type=1400 audit(0.0:321): avc: denied { ioctl } for comm="sh" path="/data/misc/perfprofd/perferr.txt" dev="sda13" ino=6817306 ioctlcmd=5401 scontext=u:r:perfprofd:s0 tcontext=u:object_r:perfprofd_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3189): avc: denied { ioctl } for comm="ps" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 type=1400 audit(0.0:3004): avc: denied { ioctl } for comm="top" path="/data/user_de/0/com.android.shell/files/bugreports/bugreport-XXXXXXXXX-MASTER-2018-10-11-16-52-40.tmp" dev="dm-2" ino=25546 ioctlcmd=0x5401 scontext=u:r:dumpstate:s0 tcontext=u:object_r:shell_data_file:s0 tclass=file permissive=0 Include the virtual sdcard when allowing F2FS specific sqlite ioctls, since apps write sqlite files to the virtual sdcard. Addresses the following denials: type=1400 audit(0.0:324): avc: denied { ioctl } for comm="amapLocManagerT" path="/storage/emulated/0/amap/openamaplocationsdk/alsn20170807.db" dev="sdcardfs" ino=3546650 ioctlcmd=f50c scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:sdcardfs:s0 tclass=file permissive=0 app=com.xiaomi.hm.health Test: policy compiles. Change-Id: I7fc570f2bbf69485b1ee6e6b2d9a421639d29123
2018-10-12 21:44:33 +02:00
allowxperm domain { file_type sdcard_type }:file ioctl {
F2FS_IOC_ABORT_VOLATILE_WRITE
F2FS_IOC_COMMIT_ATOMIC_WRITE
F2FS_IOC_GET_FEATURES
F2FS_IOC_GET_PIN_FILE
F2FS_IOC_SET_PIN_FILE
F2FS_IOC_START_ATOMIC_WRITE
};
# Workaround for policy compiler being too aggressive and removing hwservice_manager_type
# when it's not explicitly used in allow rules
allow { domain -domain } hwservice_manager_type:hwservice_manager { add find };
# Workaround for policy compiler being too aggressive and removing vndservice_manager_type
# when it's not explicitly used in allow rules
allow { domain -domain } vndservice_manager_type:service_manager { add find };
# Under ASAN, processes will try to read /data, as the sanitized libraries are there.
with_asan(`allow domain system_data_file:dir getattr;')
# Under ASAN, /system/asan.options needs to be globally accessible.
with_asan(`allow domain system_asan_options_file:file r_file_perms;')
# read APEX dir and stat any symlink pointing to APEXs.
allow domain apex_mnt_dir:dir { getattr search };
allow domain apex_mnt_dir:lnk_file r_file_perms;
###
### neverallow rules
###
# All ioctls on file-like objects (except chr_file and blk_file) and
# sockets must be restricted to a whitelist.
neverallowxperm * *:{ dir notdevfile_class_set socket_class_set blk_file } ioctl { 0 };
# b/68014825 and https://android-review.googlesource.com/516535
# rfc6093 says that processes should not use the TCP urgent mechanism
neverallowxperm domain domain:socket_class_set ioctl { SIOCATMARK };
# TIOCSTI is only ever used for exploits. Block it.
# b/33073072, b/7530569
# http://www.openwall.com/lists/oss-security/2016/09/26/14
neverallowxperm * devpts:chr_file ioctl TIOCSTI;
# Do not allow any domain other than init to create unlabeled files.
neverallow { domain -init -recovery } unlabeled:dir_file_class_set create;
# Limit device node creation to these whitelisted domains.
Allow /dev/klog access, drop mknod and __null__ access Allow vold, healthd, slideshow, and watchdogd access to /dev/kmsg. These processes log to the kernel dmesg ring buffer, so they need write access to that file. Addresses the following denials: avc: denied { write } for pid=134 comm="watchdogd" name="kmsg" dev="tmpfs" ino=9248 scontext=u:r:watchdogd:s0 tcontext=u:object_r:kmsg_device:s0 tclass=chr_file permissive=0 avc: denied { write } for pid=166 comm="healthd" name="kmsg" dev="tmpfs" ino=9248 scontext=u:r:healthd:s0 tcontext=u:object_r:kmsg_device:s0 tclass=chr_file permissive=0 avc: denied { write } for pid=180 comm="vold" name="kmsg" dev="tmpfs" ino=9248 scontext=u:r:vold:s0 tcontext=u:object_r:kmsg_device:s0 tclass=chr_file permissive=0 These denials were triggered by the change in https://android-review.googlesource.com/151209 . Prior to that change, any code which called klog_init would (unnecessarily) create the device node themselves, rather than using the already existing device node. Drop special /dev/__null__ handling from watchdogd. As of https://android-review.googlesource.com/148288 , watchdogd no longer creates it's own /dev/null device, so it's unnecessary for us to allow for it. Drop mknod from healthd, slideshow, and watchdogd. healthd and slideshow only needed mknod to create /dev/__kmsg__, which is now obsolete. watchdogd only needed mknod to create /dev/__kmsg__ and /dev/__null__, which again is now obsolete. Bug: 21242418 Change-Id: If01c8001084575e7441253f0fa8b4179ae33f534
2015-06-06 16:42:37 +02:00
neverallow {
domain
-kernel
-init
-ueventd
-vold
} self:global_capability_class_set mknod;
# No process can map low memory (< CONFIG_LSM_MMAP_MIN_ADDR).
neverallow * self:memprotect mmap_zero;
# No domain needs mac_override as it is unused by SELinux.
neverallow * self:global_capability2_class_set mac_override;
# Disallow attempts to set contexts not defined in current policy
# This helps guarantee that unknown or dangerous contents will not ever
# be set.
neverallow * self:global_capability2_class_set mac_admin;
# Once the policy has been loaded there shall be none to modify the policy.
# It is sealed.
neverallow * kernel:security load_policy;
# Only init prior to switching context should be able to set enforcing mode.
# init starts in kernel domain and switches to init domain via setcon in
# the init.rc, so the setenforce occurs while still in kernel. After
# switching domains, there is never any need to setenforce again by init.
neverallow * kernel:security setenforce;
neverallow { domain -kernel } kernel:security setcheckreqprot;
# No booleans in AOSP policy, so no need to ever set them.
neverallow * kernel:security setbool;
# Adjusting the AVC cache threshold.
# Not presently allowed to anything in policy, but possibly something
# that could be set from init.rc.
neverallow { domain -init } kernel:security setsecparam;
# Only init, ueventd, shell and system_server should be able to access HW RNG
neverallow {
domain
-init
-shell # For CTS and is restricted to getattr in shell.te
-system_server
-ueventd
} hw_random_device:chr_file *;
# b/78174219 b/64114943
neverallow {
domain
-shell # stat of /dev, getattr only
-ueventd
} keychord_device:chr_file *;
# Ensure that all entrypoint executables are in exec_type or postinstall_file.
neverallow * { file_type -exec_type -postinstall_file }:file entrypoint;
# The dynamic linker always calls access(2) on the path. Don't generate SElinux
# denials since the linker does not actually access the path in case the path
# does not exist or isn't accessible for the process.
dontaudit domain postinstall_mnt_dir:dir audit_access;
#Ensure that nothing in userspace can access /dev/port
neverallow {
domain
-shell # Shell user should not have any abilities outside of getattr
-ueventd
} port_device:chr_file *;
neverallow * port_device:chr_file ~{ create relabelto unlink setattr getattr };
Restrict the ability to set usermodehelpers and proc security settings. Limit the ability to write to the files that configure kernel usermodehelpers and security-sensitive proc settings to the init domain. Permissive domains can also continue to set these values. The current list is not exhaustive, just an initial set. Not all of these files will exist on all kernels/devices. Controlling access to certain kernel usermodehelpers, e.g. cgroup release_agent, will require kernel changes to support and cannot be addressed here. Expected output on e.g. flo after the change: ls -Z /sys/kernel/uevent_helper /proc/sys/fs/suid_dumpable /proc/sys/kernel/core_pattern /proc/sys/kernel/dmesg_restrict /proc/sys/kernel/hotplug /proc/sys/kernel/kptr_restrict /proc/sys/kernel/poweroff_cmd /proc/sys/kernel/randomize_va_space /proc/sys/kernel/usermodehelper -rw-r--r-- root root u:object_r:usermodehelper:s0 uevent_helper -rw-r--r-- root root u:object_r:proc_security:s0 suid_dumpable -rw-r--r-- root root u:object_r:usermodehelper:s0 core_pattern -rw-r--r-- root root u:object_r:proc_security:s0 dmesg_restrict -rw-r--r-- root root u:object_r:usermodehelper:s0 hotplug -rw-r--r-- root root u:object_r:proc_security:s0 kptr_restrict -rw-r--r-- root root u:object_r:usermodehelper:s0 poweroff_cmd -rw-r--r-- root root u:object_r:proc_security:s0 randomize_va_space -rw------- root root u:object_r:usermodehelper:s0 bset -rw------- root root u:object_r:usermodehelper:s0 inheritable Change-Id: I3f24b4bb90f0916ead863be6afd66d15ac5e8de0 Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
2013-12-06 15:31:40 +01:00
# Only init should be able to configure kernel usermodehelpers or
# security-sensitive proc settings.
neverallow { domain -init } usermodehelper:file { append write };
neverallow { domain -init -ueventd } sysfs_usermodehelper:file { append write };
neverallow { domain -init -vendor_init } proc_security:file { append open read write };
# Init can't do anything with binder calls. If this neverallow rule is being
# triggered, it's probably due to a service with no SELinux domain.
neverallow * init:binder *;
neverallow * vendor_init:binder *;
# Don't allow raw read/write/open access to block_device
# Rather force a relabel to a more specific type
neverallow { domain -kernel -init -recovery } block_device:blk_file { open read write };
# Do not allow renaming of block files or character files
# Ability to do so can lead to possible use in an exploit chain
# e.g. https://googleprojectzero.blogspot.com/2016/12/chrome-os-exploit-one-byte-overflow-and.html
neverallow * *:{ blk_file chr_file } rename;
# Don't allow raw read/write/open access to generic devices.
# Rather force a relabel to a more specific type.
neverallow domain device:chr_file { open read write };
# Files from cache should never be executed
neverallow domain { cache_file cache_backup_file cache_private_backup_file cache_recovery_file }:file execute;
# Protect most domains from executing arbitrary content from /data.
neverallow {
domain
-appdomain
} {
data_file_type
-dalvikcache_data_file
-system_data_file # shared libs in apks
-apk_data_file
}:file no_x_file_perms;
# The test files and executables MUST not be accessible to any domain
neverallow { domain userdebug_or_eng(`-kernel') } nativetest_data_file:file_class_set no_w_file_perms;
neverallow domain nativetest_data_file:dir no_w_dir_perms;
neverallow { domain userdebug_or_eng(`-shell') } nativetest_data_file:file no_x_file_perms;
# Only the init property service should write to /data/property and /dev/__properties__
neverallow { domain -init } property_data_file:dir no_w_dir_perms;
neverallow { domain -init } property_data_file:file { no_w_file_perms no_x_file_perms };
neverallow { domain -init } property_type:file { no_w_file_perms no_x_file_perms };
neverallow { domain -init } properties_device:file { no_w_file_perms no_x_file_perms };
neverallow { domain -init } properties_serial:file { no_w_file_perms no_x_file_perms };
# Nobody should be doing writes to /system & /vendor
# These partitions are intended to be read-only and must never be
# modified. Doing so would violate important Android security guarantees
# and invalidate dm-verity signatures.
neverallow {
domain
with_asan(`-asan_extract')
recovery_only(`userdebug_or_eng(`-fastbootd')')
} {
system_file_type
vendor_file_type
exec_type
}:dir_file_class_set { create write setattr relabelfrom append unlink link rename };
neverallow { domain -kernel with_asan(`-asan_extract') } { system_file_type vendor_file_type exec_type }:dir_file_class_set relabelto;
# Don't allow mounting on top of /system files or directories
neverallow * exec_type:dir_file_class_set mounton;
neverallow { domain -init } { system_file_type vendor_file_type }:dir_file_class_set mounton;
# Nothing should be writing to files in the rootfs.
neverallow * rootfs:file { create write setattr relabelto append unlink link rename };
# Restrict context mounts to specific types marked with
# the contextmount_type attribute.
neverallow * {fs_type -contextmount_type}:filesystem relabelto;
# Ensure that context mount types are not writable, to ensure that
# the write to /system restriction above is not bypassed via context=
# mount to another type.
neverallow * contextmount_type:dir_file_class_set
{ create setattr relabelfrom relabelto append link rename };
neverallow { domain recovery_only(`userdebug_or_eng(`-fastbootd')') } contextmount_type:dir_file_class_set { write unlink };
# Do not allow service_manager add for default service labels.
# Instead domains should use a more specific type such as
# system_app_service rather than the generic type.
# New service_types are defined in {,hw,vnd}service.te and new mappings
# from service name to service_type are defined in {,hw,vnd}service_contexts.
neverallow * default_android_service:service_manager add;
neverallow * default_android_vndservice:service_manager { add find };
Restrict access to hwservicemanager This adds fine-grained policy about who can register and find which HwBinder services in hwservicemanager. Test: Play movie in Netflix and Google Play Movies Test: Play video in YouTube app and YouTube web page Test: In Google Camera app, take photo (HDR+ and conventional), record video (slow motion and normal), and check that photos look fine and videos play back with sound. Test: Cast screen to a Google Cast device Test: Get location fix in Google Maps Test: Make and receive a phone call, check that sound works both ways and that disconnecting the call frome either end works fine. Test: Run RsHelloCompute RenderScript demo app Test: Run fast subset of media CTS tests: make and install CtsMediaTestCases.apk adb shell am instrument -e size small \ -w 'android.media.cts/android.support.test.runner.AndroidJUnitRunner' Test: Play music using Google Play music Test: Adjust screen brightness via the slider in Quick Settings Test: adb bugreport Test: Enroll in fingerprint screen unlock, unlock screen using fingerprint Test: Apply OTA update: Make some visible change, e.g., rename Settings app. make otatools && \ make dist Ensure device has network connectivity ota_call.py -s <serial here> --file out/dist/sailfish-ota-*.zip Confirm the change is now live on the device Bug: 34454312 (cherry picked from commit 632bc494f199d9d85c37c1751667fe41f4b094cb) Merged-In: Iecf74000e6c68f01299667486f3c767912c076d3 Change-Id: I7a9a487beaf6f30c52ce08e04d415624da49dd31
2017-04-14 04:05:27 +02:00
neverallow * default_android_hwservice:hwservice_manager { add find };
# Looking up the base class/interface of all HwBinder services is a bad idea.
# hwservicemanager currently offer such lookups only to make it so that security
# decisions are expressed in SELinux policy. However, it's unclear whether this
# lookup has security implications. If it doesn't, hwservicemanager should be
# modified to not offer this lookup.
# This rule can be removed if hwservicemanager is modified to not permit these
# lookups.
neverallow * hidl_base_hwservice:hwservice_manager find;
# Require that domains explicitly label unknown properties, and do not allow
# anyone but init to modify unknown properties.
neverallow { domain -init -vendor_init } default_prop:property_service set;
neverallow { domain -init -vendor_init } mmc_prop:property_service set;
compatible_property_only(`
neverallow { domain -init } default_prop:property_service set;
neverallow { domain -init } mmc_prop:property_service set;
neverallow { domain -init -vendor_init } exported_default_prop:property_service set;
neverallow { domain -init } exported_secure_prop:property_service set;
neverallow { domain -init } exported2_default_prop:property_service set;
neverallow { domain -init -vendor_init } exported3_default_prop:property_service set;
neverallow { domain -init -vendor_init } vendor_default_prop:property_service set;
')
# Only core domains are allowed to access package_manager properties
neverallow { domain -init -system_server } pm_prop:property_service set;
neverallow { domain -coredomain } pm_prop:file no_rw_file_perms;
compatible_property_only(`
neverallow { domain -init -system_server -vendor_init } exported_pm_prop:property_service set;
neverallow { domain -coredomain -vendor_init } exported_pm_prop:file no_rw_file_perms;
')
# Do not allow reading device's serial number from system properties except form
# a few whitelisted domains.
neverallow {
domain
-adbd
-dumpstate
-fastbootd
-hal_camera_server
-hal_cas_server
-hal_drm_server
-init
-mediadrmserver
-recovery
-shell
-system_server
-vendor_init
} serialno_prop:file r_file_perms;
# Do not allow reading the last boot timestamp from system properties
neverallow { domain -init -system_server -dumpstate } firstboot_prop:file r_file_perms;
neverallow {
domain
-init
-recovery
-system_server
-shell # Shell is further restricted in shell.te
-ueventd # Further restricted in ueventd.te
} frp_block_device:blk_file no_rw_file_perms;
# The metadata block device is set aside for device encryption and
# verified boot metadata. It may be reset at will and should not
# be used by other domains.
neverallow {
domain
-init
-recovery
-vold
-e2fs
-fsck
-fastbootd
} metadata_block_device:blk_file { append link rename write open read ioctl lock };
# No domain other than recovery, update_engine and fastbootd can write to system partition(s).
neverallow {
domain
-fastbootd
userdebug_or_eng(`-fsck')
userdebug_or_eng(`-init')
-recovery
-update_engine
} system_block_device:blk_file { write append };
# No domains other than a select few can access the misc_block_device. This
# block device is reserved for OTA use.
# Do not assert this rule on userdebug/eng builds, due to some devices using
# this partition for testing purposes.
neverallow {
domain
userdebug_or_eng(`-domain') # exclude debuggable builds
-fastbootd
-hal_bootctl_server
-init
-uncrypt
-update_engine
-vendor_init
-vendor_misc_writer
-vold
-recovery
-ueventd
} misc_block_device:blk_file { append link relabelfrom rename write open read ioctl lock };
# Only (hw|vnd|)servicemanager should be able to register with binder as the context manager
neverallow { domain -servicemanager -hwservicemanager -vndservicemanager } *:binder set_context_mgr;
# The service managers are only allowed to access their own device node
neverallow servicemanager hwbinder_device:chr_file no_rw_file_perms;
neverallow servicemanager vndbinder_device:chr_file no_rw_file_perms;
neverallow hwservicemanager binder_device:chr_file no_rw_file_perms;
neverallow hwservicemanager vndbinder_device:chr_file no_rw_file_perms;
neverallow vndservicemanager binder_device:chr_file no_rw_file_perms;
neverallow vndservicemanager hwbinder_device:chr_file no_rw_file_perms;
# system services cant add vendor services
neverallow {
coredomain
} vendor_service:service_manager add;
full_treble_only(`
# vendor services cant add system services
neverallow {
domain
-coredomain
-binder_in_vendor_violators # TODO(b/131617943) remove once all violators are gone
} {
service_manager_type
-vendor_service
}:service_manager add;
')
full_treble_only(`
# Vendor apps are permited to use only stable public services. If they were to use arbitrary
# services which can change any time framework/core is updated, breakage is likely.
neverallow {
appdomain
-coredomain
} {
service_manager_type
-app_api_service
-ephemeral_app_api_service
-audioserver_service # TODO(b/36783122) remove exemptions below once app_api_service is fixed
-cameraserver_service
-drmserver_service
-keystore_service
-mediadrmserver_service
-mediaextractor_service
-mediametrics_service
-mediaserver_service
-nfc_service
-radio_service
-virtual_touchpad_service
-vr_hwc_service
-vr_manager_service
}:service_manager find;
')
# On full TREBLE devices, only vendor components, shell, and su can use VendorBinder.
full_treble_only(`
neverallow {
coredomain
-shell
userdebug_or_eng(`-su')
-ueventd # uevent is granted create for this device, but we still neverallow I/O below
} vndbinder_device:chr_file rw_file_perms;
')
full_treble_only(`
neverallow ueventd vndbinder_device:chr_file { read write append ioctl };
')
full_treble_only(`
neverallow {
coredomain
-shell
userdebug_or_eng(`-su')
} vndservice_manager_type:service_manager *;
')
full_treble_only(`
neverallow {
coredomain
-shell
userdebug_or_eng(`-su')
} vndservicemanager:binder *;
')
# On full TREBLE devices, socket communications between core components and vendor components are
# not permitted.
# Most general rules first, more specific rules below.
# Core domains are not permitted to initiate communications to vendor domain sockets.
# We are not restricting the use of already established sockets because it is fine for a process
# to obtain an already established socket via some public/official/stable API and then exchange
# data with its peer over that socket. The wire format in this scenario is dicatated by the API
# and thus does not break the core-vendor separation.
full_treble_only(`
neverallow_establish_socket_comms({
coredomain
-init
-adbd
}, {
domain
-coredomain
-socket_between_core_and_vendor_violators
});
')
# Vendor domains are not permitted to initiate communications to core domain sockets
full_treble_only(`
neverallow_establish_socket_comms({
domain
-coredomain
-appdomain
-socket_between_core_and_vendor_violators
}, {
coredomain
-logd # Logging by writing to logd Unix domain socket is public API
-netd # netdomain needs this
-mdnsd # netdomain needs this
userdebug_or_eng(`-su') # communications with su are permitted only on userdebug or eng builds
-init
-tombstoned # linker to tombstoned
userdebug_or_eng('-heapprofd`)
});
')
# Vendor domains are not permitted to initiate create/open sockets owned by core domains
full_treble_only(`
neverallow {
domain
-coredomain
-appdomain # appdomain restrictions below
-data_between_core_and_vendor_violators # b/70393317
-socket_between_core_and_vendor_violators
-vendor_init
} {
coredomain_socket
core_data_file_type
unlabeled # used only by core domains
}:sock_file ~{ append getattr ioctl read write };
')
full_treble_only(`
neverallow {
appdomain
-coredomain
} {
coredomain_socket
unlabeled # used only by core domains
core_data_file_type
-app_data_file
-privapp_data_file
-pdx_endpoint_socket_type # used by VR layer
-pdx_channel_socket_type # used by VR layer
}:sock_file ~{ append getattr ioctl read write };
')
# Core domains are not permitted to create/open sockets owned by vendor domains
full_treble_only(`
neverallow {
coredomain
-init
-ueventd
-socket_between_core_and_vendor_violators
} {
file_type
dev_type
-coredomain_socket
-core_data_file_type
-unlabeled
}:sock_file ~{ append getattr ioctl read write };
')
# On TREBLE devices, vendor and system components are only allowed to share
# files by passing open FDs over hwbinder. Ban all directory access and all file
# accesses other than what can be applied to an open FD such as
# ioctl/stat/read/write/append. This is enforced by segregating /data.
# Vendor domains may directly access file in /data/vendor by path, but may only
# access files outside of /data/vendor via an open FD passed over hwbinder.
# Likewise, core domains may only directly access files outside /data/vendor by
# path and files in /data/vendor by open FD.
full_treble_only(`
# only coredomains may only access core_data_file_type, particularly not
# /data/vendor
neverallow {
coredomain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-data_between_core_and_vendor_violators
-init
-vold_prepare_subdirs
} {
data_file_type
-core_data_file_type
}:file_class_set ~{ append getattr ioctl read write map };
')
full_treble_only(`
neverallow {
coredomain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-data_between_core_and_vendor_violators
-init
-vold_prepare_subdirs
} {
data_file_type
-core_data_file_type
# TODO(b/72998741) Remove exemption. Further restricted in a subsequent
# neverallow. Currently only getattr and search are allowed.
-vendor_data_file
}:dir *;
')
full_treble_only(`
# vendor domains may only access files in /data/vendor, never core_data_file_types
neverallow {
domain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
-vendor_init
} {
core_data_file_type
# libc includes functions like mktime and localtime which attempt to access
# files in /data/misc/zoneinfo/tzdata and /system/usr/share/zoneinfo/tzdata.
# These functions are considered vndk-stable and thus must be allowed for
# all processes.
-zoneinfo_data_file
with_native_coverage(`-method_trace_data_file')
}:file_class_set ~{ append getattr ioctl read write map };
neverallow {
vendor_init
-data_between_core_and_vendor_violators
} {
core_data_file_type
-unencrypted_data_file
-zoneinfo_data_file
with_native_coverage(`-method_trace_data_file')
}:file_class_set ~{ append getattr ioctl read write map };
# vendor init needs to be able to read unencrypted_data_file to create directories with FBE.
# The vendor init binary lives on the system partition so there is not a concern with stability.
neverallow vendor_init unencrypted_data_file:file ~r_file_perms;
')
full_treble_only(`
# vendor domains may only access dirs in /data/vendor, never core_data_file_types
neverallow {
domain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-coredomain
-data_between_core_and_vendor_violators
-vendor_init
} {
core_data_file_type
-system_data_file # default label for files on /data. Covered below...
-system_data_root_file
-vendor_data_file
-zoneinfo_data_file
with_native_coverage(`-method_trace_data_file')
}:dir *;
neverallow {
vendor_init
-data_between_core_and_vendor_violators
} {
core_data_file_type
-unencrypted_data_file
-system_data_file
-system_data_root_file
-vendor_data_file
-zoneinfo_data_file
with_native_coverage(`-method_trace_data_file')
}:dir *;
# vendor init needs to be able to read unencrypted_data_file to create directories with FBE.
# The vendor init binary lives on the system partition so there is not a concern with stability.
neverallow vendor_init unencrypted_data_file:dir ~search;
')
full_treble_only(`
# vendor domains may only access dirs in /data/vendor, never core_data_file_types
neverallow {
domain
-appdomain # TODO(b/34980020) remove exemption for appdomain
-coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
} {
system_data_file # default label for files on /data. Covered below
}:dir ~{ getattr search };
')
full_treble_only(`
# coredomains may not access dirs in /data/vendor.
neverallow {
coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
-init
-vold # vold creates per-user storage for both system and vendor
-vold_prepare_subdirs
} {
vendor_data_file # default label for files on /data. Covered below
}:dir ~{ getattr search };
')
full_treble_only(`
# coredomains may not access dirs in /data/vendor.
neverallow {
coredomain
-data_between_core_and_vendor_violators # TODO(b/34980020) Remove once all violators have been cleaned up
-init
} {
vendor_data_file # default label for files on /data/vendor{,_ce,_de}.
}:file_class_set ~{ append getattr ioctl read write map };
')
full_treble_only(`
# Non-vendor domains are not allowed to file execute shell
# from vendor
neverallow {
coredomain
-init
-shell
-ueventd
} vendor_shell_exec:file { execute execute_no_trans };
')
full_treble_only(`
# Do not allow vendor components to execute files from system
# except for the ones whitelist here.
neverallow {
domain
-coredomain
-appdomain
-vendor_executes_system_violators
-vendor_init
} {
system_file_type
-system_lib_file
-system_linker_exec
-crash_dump_exec
-netutils_wrapper_exec
userdebug_or_eng(`-tcpdump_exec')
}:file { entrypoint execute execute_no_trans };
')
full_treble_only(`
# Do not allow system components to execute files from vendor
# except for the ones whitelisted here.
neverallow {
coredomain
-init
-shell
-system_executes_vendor_violators
-ueventd
} {
vendor_file_type
-same_process_hal_file
-vndk_sp_file
-vendor_app_file
-vendor_public_lib_file
}:file execute;
')
full_treble_only(`
neverallow {
coredomain
-shell
-system_executes_vendor_violators
} {
vendor_file_type
-same_process_hal_file
}:file execute_no_trans;
')
full_treble_only(`
# Do not allow system components access to /vendor files except for the
# ones whitelisted here.
neverallow {
coredomain
# TODO(b/37168747): clean up fwk access to /vendor
-crash_dump
-init # starts vendor executables
-kernel # loads /vendor/firmware
userdebug_or_eng(`-heapprofd')
-shell
-system_executes_vendor_violators
-ueventd # reads /vendor/ueventd.rc
} {
vendor_file_type
-same_process_hal_file
-vendor_app_file
-vendor_apex_file
-vendor_configs_file
-vendor_framework_file
-vendor_idc_file
-vendor_keychars_file
-vendor_keylayout_file
-vendor_overlay_file
-vendor_public_lib_file
-vendor_task_profiles_file
-vndk_sp_file
}:file *;
')
full_treble_only(`
# Do not allow vendor components access to /system files except for the
# ones whitelisted here.
neverallow {
domain
-appdomain
-coredomain
-vendor_executes_system_violators
# vendor_init needs access to init_exec for domain transition. vendor_init
# neverallows are covered in public/vendor_init.te
-vendor_init
} {
system_file_type
-crash_dump_exec
-file_contexts_file
-netutils_wrapper_exec
-property_contexts_file
-system_event_log_tags_file
-system_group_file
-system_lib_file
with_asan(`-system_asan_options_file')
-system_linker_exec
-system_linker_config_file
-system_passwd_file
-system_seccomp_policy_file
-system_security_cacerts_file
-system_zoneinfo_file
-task_profiles_file
userdebug_or_eng(`-tcpdump_exec')
}:file *;
')
# Only system_server should be able to send commands via the zygote socket
neverallow { domain -zygote -system_server } zygote:unix_stream_socket connectto;
neverallow { domain -system_server } zygote_socket:sock_file write;
neverallow { domain -system_server -webview_zygote -app_zygote } webview_zygote:unix_stream_socket connectto;
neverallow { domain -system_server } webview_zygote:sock_file write;
neverallow { domain -system_server } app_zygote:sock_file write;
neverallow {
domain
-tombstoned
-crash_dump
-dumpstate
-incidentd
-system_server
# Processes that can't exec crash_dump
-hal_codec2_server
-hal_omx_server
-mediaextractor
} tombstoned_crash_socket:unix_stream_socket connectto;
# Never allow anyone except dumpstate, incidentd, or the system server to connect or write to
# the tombstoned intercept socket.
neverallow { domain -dumpstate -incidentd -system_server } tombstoned_intercept_socket:sock_file write;
neverallow { domain -dumpstate -incidentd -system_server } tombstoned_intercept_socket:unix_stream_socket connectto;
# Android does not support System V IPCs.
#
# The reason for this is due to the fact that, by design, they lead to global
# kernel resource leakage.
#
# For example, there is no way to automatically release a SysV semaphore
# allocated in the kernel when:
#
# - a buggy or malicious process exits
# - a non-buggy and non-malicious process crashes or is explicitly killed.
#
# Killing processes automatically to make room for new ones is an
# important part of Android's application lifecycle implementation. This means
# that, even assuming only non-buggy and non-malicious code, it is very likely
# that over time, the kernel global tables used to implement SysV IPCs will fill
# up.
neverallow * *:{ shm sem msg msgq } *;
# Do not mount on top of symlinks, fifos, or sockets.
# Feature parity with Chromium LSM.
neverallow * { file_type fs_type dev_type }:{ lnk_file fifo_file sock_file } mounton;
# Nobody should be able to execute su on user builds.
# On userdebug/eng builds, only dumpstate, shell, and
# su itself execute su.
neverallow { domain userdebug_or_eng(`-dumpstate -shell -su') } su_exec:file no_x_file_perms;
# Do not allow the introduction of new execmod rules. Text relocations
# and modification of executable pages are unsafe.
# The only exceptions are for NDK text relocations associated with
# https://code.google.com/p/android/issues/detail?id=23203
# which, long term, need to go away.
neverallow * {
file_type
-apk_data_file
-app_data_file
-asec_public_file
}:file execmod;
# Do not allow making the stack or heap executable.
# We would also like to minimize execmem but it seems to be
# required by some device-specific service domains.
neverallow * self:process { execstack execheap };
# Do not allow the introduction of new execmod rules. Text relocations
# and modification of executable pages are unsafe.
neverallow { domain -untrusted_app_25 -untrusted_app_27 } file_type:file execmod;
neverallow { domain -init } proc:{ file dir } mounton;
# Ensure that all types assigned to processes are included
# in the domain attribute, so that all allow and neverallow rules
# written on domain are applied to all processes.
# This is achieved by ensuring that it is impossible to transition
# from a domain to a non-domain type and vice versa.
# TODO - rework this: neverallow domain ~domain:process { transition dyntransition };
neverallow ~domain domain:process { transition dyntransition };
#
# Only system_app and system_server should be creating or writing
# their files. The proper way to share files is to setup
# type transitions to a more specific type or assigning a type
# to its parent directory via a file_contexts entry.
# Example type transition:
# mydomain.te:file_type_auto_trans(mydomain, system_data_file, new_file_type)
#
neverallow {
domain
-system_server
-system_app
-init
-toolbox # TODO(b/141108496) We want to remove toolbox
-installd # for relabelfrom and unlink, check for this in explicit neverallow
-vold_prepare_subdirs # For unlink
with_asan(`-asan_extract')
} system_data_file:file no_w_file_perms;
# do not grant anything greater than r_file_perms and relabelfrom unlink
# to installd
neverallow installd system_data_file:file ~{ r_file_perms relabelfrom unlink };
# respect system_app sandboxes
neverallow {
domain
-appdomain # finer-grained rules for appdomain are listed below
-system_server #populate com.android.providers.settings/databases/settings.db.
-installd # creation of app sandbox
-traced_probes # resolve inodes for i/o tracing.
# only needs open and read, the rest is neverallow in
# traced_probes.te.
} system_app_data_file:dir_file_class_set { create unlink open };
neverallow {
isolated_app
untrusted_app_all # finer-grained rules for appdomain are listed below
ephemeral_app
priv_app
} system_app_data_file:dir_file_class_set { create unlink open };
#
# Only these domains should transition to shell domain. This domain is
# permissible for the "shell user". If you need a process to exec a shell
# script with differing privilege, define a domain and set up a transition.
#
neverallow {
domain
-adbd
-init
-runas
-zygote
} shell:process { transition dyntransition };
# Only domains spawned from zygote, runas and simpleperf_app_runner may have the appdomain
# attribute.
neverallow { domain -simpleperf_app_runner -runas -app_zygote -webview_zygote -zygote } {
appdomain -shell userdebug_or_eng(`-su')
}:process { transition dyntransition };
# Minimize read access to shell- or app-writable symlinks.
# This is to prevent malicious symlink attacks.
neverallow {
domain
-appdomain
-installd
} { app_data_file privapp_data_file }:lnk_file read;
neverallow {
domain
-shell
userdebug_or_eng(`-uncrypt')
-installd
} shell_data_file:lnk_file read;
# In addition to the symlink reading restrictions above, restrict
# write access to shell owned directories. The /data/local/tmp
# directory is untrustworthy, and non-whitelisted domains should
# not be trusting any content in those directories.
neverallow {
domain
-adbd
-dumpstate
-installd
-init
-shell
-vold
} shell_data_file:dir no_w_dir_perms;
neverallow {
domain
-adbd
-appdomain
-dumpstate
-init
-installd
-simpleperf_app_runner
-system_server # why?
userdebug_or_eng(`-uncrypt')
} shell_data_file:dir { open search };
# Same as above for /data/local/tmp files. We allow shell files
# to be passed around by file descriptor, but not directly opened.
neverallow {
domain
-adbd
-appdomain
-dumpstate
-installd
userdebug_or_eng(`-uncrypt')
} shell_data_file:file open;
# servicemanager and vndservicemanager are the only processes which handle the
# service_manager list request
neverallow * ~{
servicemanager
vndservicemanager
}:service_manager list;
# hwservicemanager is the only process which handles hw list requests
neverallow * ~{
hwservicemanager
}:hwservice_manager list;
# only service_manager_types can be added to service_manager
# TODO - rework this: neverallow * ~service_manager_type:service_manager { add find };
# Prevent assigning non property types to properties
# TODO - rework this: neverallow * ~property_type:property_service set;
# Domain types should never be assigned to any files other
# than the /proc/pid files associated with a process. The
# executable file used to enter a domain should be labeled
# with its own _exec type, not with the domain type.
# Conventionally, this looks something like:
# $ cat mydaemon.te
# type mydaemon, domain;
# type mydaemon_exec, exec_type, file_type;
# init_daemon_domain(mydaemon)
# $ grep mydaemon file_contexts
# /system/bin/mydaemon -- u:object_r:mydaemon_exec:s0
neverallow * domain:file { execute execute_no_trans entrypoint };
# Do not allow access to the generic debugfs label. This is too broad.
# Instead, if access to part of debugfs is desired, it should have a
# more specific label.
# TODO: fix dumpstate
neverallow { domain -init -vendor_init -dumpstate } debugfs:{ file lnk_file } no_rw_file_perms;
# Do not allow executable files in debugfs.
neverallow domain debugfs_type:file { execute execute_no_trans };
# Profiles contain untrusted data and profman parses that. We should only run
# in from installd forked processes.
neverallow {
domain
-installd
-profman
} profman_exec:file no_x_file_perms;
# Enforce restrictions on kernel module origin.
# Do not allow kernel module loading except from system,
# vendor, and boot partitions.
neverallow * ~{ system_file vendor_file rootfs }:system module_load;
# Only allow filesystem caps to be set at build time. Runtime changes
# to filesystem capabilities are not permitted.
neverallow * self:global_capability_class_set setfcap;
# Enforce AT_SECURE for executing crash_dump.
neverallow domain crash_dump:process noatsecure;
Assert apps can access only approved HwBinder services App domains which host arbitrary code must not have access to arbitrary HwBinder services. Such access unnecessarily increases the attack surface. The reason is twofold: 1. HwBinder servers do not perform client authentication because HIDL currently does not expose caller UID information and, even if it did, many HwBinder services either operate at a layer below that of apps (e.g., HALs) or must not rely on app identity for authorization. Thus, to be safe, the default assumption is that a HwBinder service treats all its clients as equally authorized to perform operations offered by the service. 2. HAL servers (a subset of HwBinder services) contain code with higher incidence rate of security issues than system/core components and have access to lower layes of the stack (all the way down to hardware) thus increasing opportunities for bypassing the Android security model. HwBinder services offered by core components (as opposed to vendor components) are considered safer because of point #2 above. Always same-process aka always-passthrough HwBinder services are considered safe for access by these apps. This is because these HALs by definition do not offer any additional access beyond what its client already as, because these services run in the process of the client. This commit thus introduces these two categories of HwBinder services in neverallow rules. Test: mmm system/sepolicy -- this does not change on-device policy Bug: 34454312 Change-Id: I4f5f4dd10b3fc3bb9d262dda532d4a23dcdf061d
2017-04-22 02:06:43 +02:00
# Do not permit non-core domains to register HwBinder services which are
# guaranteed to be provided by core domains only.
neverallow ~coredomain coredomain_hwservice:hwservice_manager add;
# Do not permit the registeration of HwBinder services which are guaranteed to
# be passthrough only (i.e., run in the process of their clients instead of a
# separate server process).
neverallow * same_process_hwservice:hwservice_manager add;
# On TREBLE devices, most coredomains should not access vendor_files.
# TODO(b/71553434): Remove exceptions here.
full_treble_only(`
neverallow {
coredomain
-appdomain
-bootanim
-crash_dump
-init
-kernel
-heapprofd
-ueventd
} vendor_file:file { no_w_file_perms no_x_file_perms open };
')
# If an already existing file is opened with O_CREAT, the kernel might generate
# a false report of a create denial. Silence these denials and make sure that
# inappropriate permissions are not granted.
# These filesystems don't allow files or directories to be created, so the permission
# to do so should never be granted.
neverallow domain {
proc_type
sysfs_type
}:dir { add_name create link remove_name rename reparent rmdir write };
# cgroupfs directories can be created, but not files within them.
neverallow domain cgroup:file create;
dontaudit domain proc_type:dir write;
dontaudit domain sysfs_type:dir write;
dontaudit domain cgroup:file create;
# These are only needed in permissive mode - in enforcing mode the
# directory write check fails and so these are never attempted.
userdebug_or_eng(`
dontaudit domain proc_type:dir add_name;
dontaudit domain sysfs_type:dir add_name;
dontaudit domain proc_type:file create;
dontaudit domain sysfs_type:file create;
')
# Platform must not have access to /mnt/vendor.
neverallow {
coredomain
-init
-ueventd
-vold
-system_writes_mnt_vendor_violators
} mnt_vendor_file:dir *;
# Only apps are allowed access to vendor public libraries.
full_treble_only(`
neverallow {
coredomain
-appdomain
} vendor_public_lib_file:file { execute execute_no_trans };
')
# Vendor domian must not have access to /mnt/product.
neverallow {
domain
-coredomain
} mnt_product_file:dir *;
# Platform must not have access to sysfs_batteryinfo, but should do it via health HAL and healthd
full_treble_only(`
neverallow {
coredomain
-healthd
-shell
# Generate uevents for health info
-ueventd
# Recovery uses health HAL passthrough implementation.
-recovery
# Charger uses health HAL passthrough implementation.
-charger
# TODO(b/110891300): remove this exception
-incidentd
} sysfs_batteryinfo:file { open read };
')
neverallow {
domain
-hal_codec2_server
-hal_omx_server
} hal_codec2_hwservice:hwservice_manager add;
# Only apps targetting < Q are allowed to open /dev/ashmem directly.
# Apps must use ASharedMemory NDK API. Native code must use libcutils API.
neverallow {
domain
-ephemeral_app # We don't distinguish ephemeral apps based on target API.
-untrusted_app_25
-untrusted_app_27
} ashmem_device:chr_file open;