platform_system_sepolicy/public/webview_zygote.te
Robert Sesek dc43f7cd84 Add the "webview_zygote" domain.
The webview_zygote is a new unprivileged zygote and has its own sockets for
listening to fork requests. However the webview_zygote does not run as root
(though it does require certain capabilities) and only allows dyntransition to
the isolated_app domain.

Test: m
Test: angler boots

Bug: 21643067
Change-Id: I89a72ffe6dcb983c4a44048518efd7efb7ed8e83
2016-11-11 10:13:17 -05:00

83 lines
3.1 KiB
Text

# webview_zygote is an auxiliary zygote process that is used to spawn
# isolated_app processes for rendering untrusted web content.
# The webview_zygote needs to be able to transition domains.
type webview_zygote, domain, mlstrustedsubject;
type webview_zygote_exec, exec_type, file_type;
# Access to system files for SELinux contexts.
allow webview_zygote rootfs:file r_file_perms;
# Access to the WebView relro file.
allow webview_zygote shared_relro_file:dir search;
allow webview_zygote shared_relro_file:file r_file_perms;
# Set the UID/GID of the process.
allow webview_zygote self:capability { setgid setuid };
# Drop capabilities from bounding set.
allow webview_zygote self:capability setpcap;
# Switch SELinux context to app domains.
allow webview_zygote self:process setcurrent;
allow webview_zygote isolated_app:process dyntransition;
# For art.
allow webview_zygote dalvikcache_data_file:dir r_dir_perms;
allow webview_zygote dalvikcache_data_file:lnk_file r_file_perms;
allow webview_zygote dalvikcache_data_file:file { r_file_perms execute };
# Allow webview_zygote to manage the pgroup of its children.
allow webview_zygote system_server:process getpgid;
# Interaction between the webview_zygote and its children.
allow webview_zygote isolated_app:process setpgid;
# Check validity of SELinux context before use.
selinux_check_context(webview_zygote)
# Check SELinux permissions.
selinux_check_access(webview_zygote)
#####
##### Neverallow
#####
# Only permit transition to isolated_app.
neverallow webview_zygote { domain -isolated_app }:process dyntransition;
# Disallow write access to properties.
neverallow webview_zygote property_socket:sock_file write;
neverallow webview_zygote property_type:property_service set;
# Should not have any access to app data files.
neverallow webview_zygote {
app_data_file
system_app_data_file
bluetooth_data_file
nfc_data_file
radio_data_file
shell_data_file
ephemeral_data_file
}:file { rwx_file_perms };
neverallow webview_zygote {
service_manager_type
-activity_service
-webviewupdate_service
}:service_manager find;
# Isolated apps shouldn't be able to access the driver directly.
neverallow webview_zygote gpu_device:chr_file { rwx_file_perms };
# Do not allow webview_zygote access to /cache.
neverallow webview_zygote cache_file:dir ~{ r_dir_perms };
neverallow webview_zygote cache_file:file ~{ read getattr };
# Do not allow most socket access. This is socket_class_set, excluding unix_dgram_socket,
# unix_stream_socket, and netlink_selinux_socket.
neverallow webview_zygote domain:{
socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket
appletalk_socket netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket
netlink_nflog_socket netlink_xfrm_socket netlink_audit_socket netlink_ip6fw_socket
netlink_dnrt_socket netlink_kobject_uevent_socket tun_socket netlink_iscsi_socket
netlink_fib_lookup_socket netlink_connector_socket netlink_netfilter_socket
netlink_generic_socket netlink_scsitransport_socket netlink_rdma_socket netlink_crypto_socket
} *;