platform_system_sepolicy/prebuilts/api/33.0/public/hal_neverallows.te
Yurii Zubrytskyi 04a85a1ba0 platform/system/sepolicy - SEPolicy Prebuilts for Tiramisu
Ignore-AOSP-First: T finalization
Bug: 225745567
Test: Build
Change-Id: I49fb91c7a60fb1e871bdf3553d978bb16c476fd7
Merged-In: I49fb91c7a60fb1e871bdf3553d978bb16c476fd7
2022-05-04 09:46:16 -07:00

92 lines
3.7 KiB
Text

# only HALs responsible for network hardware should have privileged
# network capabilities
neverallow {
halserverdomain
-hal_bluetooth_server
-hal_can_controller_server
-hal_wifi_server
-hal_wifi_hostapd_server
-hal_wifi_supplicant_server
-hal_telephony_server
-hal_uwb_server
# TODO(b/196225233): Remove hal_uwb_vendor_server
-hal_uwb_vendor_server
-hal_nlinterceptor_server
} self:global_capability_class_set { net_admin net_raw };
# Unless a HAL's job is to communicate over the network, or control network
# hardware, it should not be using network sockets.
# NOTE: HALs for automotive devices have an exemption from this rule because in
# a car it is common to have external modules and HALs need to communicate to
# those modules using network. Using this exemption for non-automotive builds
# will result in CTS failure.
neverallow {
halserverdomain
-hal_automotive_socket_exemption
-hal_can_controller_server
-hal_tetheroffload_server
-hal_wifi_server
-hal_wifi_hostapd_server
-hal_wifi_supplicant_server
-hal_telephony_server
-hal_uwb_server
# TODO(b/196225233): Remove hal_uwb_vendor_server
-hal_uwb_vendor_server
-hal_nlinterceptor_server
} domain:{ udp_socket rawip_socket } *;
neverallow {
halserverdomain
-hal_automotive_socket_exemption
-hal_can_controller_server
-hal_tetheroffload_server
-hal_wifi_server
-hal_wifi_hostapd_server
-hal_wifi_supplicant_server
-hal_telephony_server
-hal_nlinterceptor_server
} {
domain
userdebug_or_eng(`-su')
}:tcp_socket *;
# The UWB HAL is not actually a networking HAL but may need to bring up and down
# interfaces. Restrict it to only these networking operations.
neverallow hal_uwb_vendor_server self:global_capability_class_set { net_raw };
# Subset of socket_class_set likely to be usable for communication or accessible through net_admin.
# udp_socket is required to use interface ioctls.
neverallow hal_uwb_vendor_server domain:{ socket rawip_socket netlink_socket packet_socket key_socket netlink_route_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_dnrt_socket netlink_kobject_uevent_socket tun_socket netlink_iscsi_socket netlink_fib_lookup_socket netlink_connector_socket netlink_netfilter_socket netlink_scsitransport_socket netlink_rdma_socket netlink_crypto_socket qipcrtr_socket xdp_socket } *;
###
# HALs are defined as an attribute and so a given domain could hypothetically
# have multiple HALs in it (or even all of them) with the subsequent policy of
# the domain comprised of the union of all the HALs.
#
# This is a problem because
# 1) Security sensitive components should only be accessed by specific HALs.
# 2) hwbinder_call and the restrictions it provides cannot be reasoned about in
# the platform.
# 3) The platform cannot reason about defense in depth if there are
# monolithic domains etc.
#
# As an example, hal_keymaster and hal_gatekeeper can access the TEE and while
# its OK for them to share a process its not OK with them to share processes
# with other hals.
#
# The following neverallow rules, in conjuntion with CTS tests, assert that
# these security principles are adhered to.
#
# Do not allow a hal to exec another process without a domain transition.
# TODO remove exemptions.
neverallow {
halserverdomain
-hal_dumpstate_server
-hal_telephony_server
} { file_type fs_type }:file execute_no_trans;
# Do not allow a process other than init to transition into a HAL domain.
neverallow { domain -init } halserverdomain:process transition;
# Only allow transitioning to a domain by running its executable. Do not
# allow transitioning into a HAL domain by use of seclabel in an
# init.*.rc script.
neverallow * halserverdomain:process dyntransition;