# Networking service app typeattribute network_stack coredomain; typeattribute network_stack mlstrustedsubject; typeattribute network_stack bpfdomain; app_domain(network_stack); net_domain(network_stack); allow network_stack self:global_capability_class_set { net_admin net_bind_service net_broadcast net_raw }; allow network_stack self:global_capability2_class_set wake_alarm; # Allow access to net_admin ioctl, DHCP server uses SIOCSARP allowxperm network_stack self:udp_socket ioctl priv_sock_ioctls; # The DhcpClient uses packet_sockets allow network_stack self:packet_socket create_socket_perms_no_ioctl; # Monitor neighbors via netlink. allow network_stack self:netlink_route_socket nlmsg_write; # Use netlink uevent sockets. allow network_stack self:netlink_kobject_uevent_socket create_socket_perms_no_ioctl; # give network_stack the same netlink permissions as netd allow network_stack self:netlink_nflog_socket create_socket_perms_no_ioctl; allow network_stack self:netlink_socket create_socket_perms_no_ioctl; allow network_stack self:netlink_generic_socket create_socket_perms_no_ioctl; allow network_stack app_api_service:service_manager find; allow network_stack dnsresolver_service:service_manager find; allow network_stack mdns_service:service_manager find; allow network_stack netd_service:service_manager find; allow network_stack network_watchlist_service:service_manager find; allow network_stack radio_service:service_manager find; allow network_stack system_config_service:service_manager find; allow network_stack radio_data_file:dir create_dir_perms; allow network_stack radio_data_file:file create_file_perms; binder_call(network_stack, netd); # in order to invoke side effect of close() on such a socket calling synchronize_rcu() allow network_stack self:key_socket create; # Java's Os.close() in libcore/luni/src/main/java/libcore/io/BlockGuardOs.java;l=100 # calls if (fd.isSocket$()) if (isLingerSocket(fd)) ... dontaudit network_stack self:key_socket getopt; # Grant read permission of connectivity namespace system property prefix. get_prop(network_stack, device_config_connectivity_prop) # Create/use netlink_tcpdiag_socket to get tcp info allow network_stack self:netlink_tcpdiag_socket { create_socket_perms_no_ioctl nlmsg_read nlmsg_write }; ############### Tethering Service app - Tethering.apk ############## hal_client_domain(network_stack, hal_tetheroffload) # Create and share netlink_netfilter_sockets for tetheroffload. allow network_stack self:netlink_netfilter_socket create_socket_perms_no_ioctl; allow network_stack network_stack_service:service_manager find; # allow Tethering(network_stack process) to run/update/read the eBPF maps to offload tethering traffic by eBPF. allow network_stack { fs_bpf_net_private fs_bpf_net_shared fs_bpf_netd_readonly fs_bpf_netd_shared fs_bpf_tethering }:dir search; allow network_stack { fs_bpf_net_private fs_bpf_net_shared fs_bpf_netd_readonly fs_bpf_netd_shared fs_bpf_tethering }:file { getattr read write }; allow network_stack bpfloader:bpf { map_read map_write prog_run }; # allow Tethering(network_stack process) to read flag value in tethering_u_or_later_native namespace get_prop(network_stack, device_config_tethering_u_or_later_native_prop) # Use XFRM (IPsec) netlink sockets allow network_stack self:netlink_xfrm_socket { create_socket_perms_no_ioctl nlmsg_write nlmsg_read }; # tun device used for 3rd party vpn apps and test network manager allow network_stack tun_device:chr_file rw_file_perms; allowxperm network_stack tun_device:chr_file ioctl { TUNGETIFF TUNSETIFF TUNSETLINK TUNSETCARRIER }; ############### NEVER ALLOW RULES # This place is as good as any for these rules, # and it is probably the most appropriate because # network_stack itself is entirely mainline code. # T+: Only the bpfloader and the network_stack should ever touch 'fs_bpf_net_private' programs/maps. neverallow { domain -bpfloader -network_stack } fs_bpf_net_private:dir ~getattr; neverallow { domain -bpfloader -network_stack } fs_bpf_net_private:file *; # T+: Only the bpfloader, network_stack and system_server should ever touch 'fs_bpf_net_shared' programs/maps. neverallow { domain -bpfloader -network_stack -system_server } fs_bpf_net_shared:dir ~getattr; neverallow { domain -bpfloader -network_stack -system_server } fs_bpf_net_shared:file *; # T+: Only the bpfloader, netd, network_stack and system_server should ever touch 'fs_bpf_netd_readonly' programs/maps. # netd's access should be readonly neverallow { domain -bpfloader -netd -network_stack -system_server } fs_bpf_netd_readonly:dir ~getattr; neverallow { domain -bpfloader -netd -network_stack -system_server } fs_bpf_netd_readonly:file *; neverallow netd fs_bpf_netd_readonly:file write; # T+: Only the bpfloader, netd, netutils_wrapper, network_stack and system_server should ever touch 'fs_bpf_netd_shared' programs/maps. # netutils_wrapper requires access to be able to run iptables and only needs readonly access neverallow { domain -bpfloader -netd -netutils_wrapper -network_stack -system_server } fs_bpf_netd_shared:dir ~getattr; neverallow { domain -bpfloader -netd -netutils_wrapper -network_stack -system_server } fs_bpf_netd_shared:file *; neverallow netutils_wrapper fs_bpf_netd_shared:file write; # S+: Only the bpfloader and the network_stack should ever touch 'fs_bpf_tethering' programs/maps. neverallow { domain -bpfloader -network_stack } fs_bpf_tethering:dir ~getattr; neverallow { domain -bpfloader -network_stack } fs_bpf_tethering:file *;