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    ### Services with isolatedProcess=true in their manifest.
    ###
    ### This file defines the rules for isolated apps. An "isolated
    ### app" is an APP with UID between AID_ISOLATED_START (99000)
    ### and AID_ISOLATED_END (99999).
    ###
    
    
    app_domain(isolated_app)
    
    # Access already open app data files received over Binder or local socket IPC.
    allow isolated_app app_data_file:file { append read write getattr lock };
    
    allow isolated_app activity_service:service_manager find;
    allow isolated_app display_service:service_manager find;
    allow isolated_app webviewupdate_service:service_manager find;
    
    # Google Breakpad (crash reporter for Chrome) relies on ptrace
    # functionality. Without the ability to ptrace, the crash reporter
    # tool is broken.
    # b/20150694
    # https://code.google.com/p/chromium/issues/detail?id=475270
    allow isolated_app self:process ptrace;
    
    # b/32896414: Allow accessing sdcard file descriptors passed to isolated_apps
    # by other processes. Open should never be allowed, and is blocked by
    # neverallow rules below.
    # TODO: consider removing write/append. We want to limit isolated_apps
    # ability to mutate files of any type.
    # media_rw_data_file is included for sdcardfs, and can be removed if sdcardfs
    # is modified to change the secontext when accessing the lower filesystem.
    allow isolated_app { sdcard_type media_rw_data_file }:file { read write append getattr lock };
    auditallow isolated_app { sdcard_type media_rw_data_file }:file { write append };
    
    # For webviews, isolated_app processes can be forked from the webview_zygote
    # in addition to the zygote. Allow access to resources inherited from the
    # webview_zygote process. These rules are specialized copies of the ones in app.te.
    # Inherit FDs from the webview_zygote.
    allow isolated_app webview_zygote:fd use;
    # Notify webview_zygote of child death.
    allow isolated_app webview_zygote:process sigchld;
    # Inherit logd write socket.
    allow isolated_app webview_zygote:unix_dgram_socket write;
    
    # Read system properties managed by webview_zygote.
    allow isolated_app webview_zygote_tmpfs:file read;
    
    
    #####
    ##### Neverallow
    #####
    
    # Do not allow isolated_app to directly open tun_device
    neverallow isolated_app tun_device:chr_file open;
    
    # Do not allow isolated_app to set system properties.
    neverallow isolated_app property_socket:sock_file write;
    neverallow isolated_app property_type:property_service set;
    
    # Isolated apps should not directly open app data files themselves.
    neverallow isolated_app app_data_file:file open;
    
    # Only allow appending to /data/anr/traces.txt (b/27853304, b/18340553)
    # TODO: are there situations where isolated_apps write to this file?
    # TODO: should we tighten these restrictions further?
    neverallow isolated_app anr_data_file:file ~{ open append };
    neverallow isolated_app anr_data_file:dir ~search;
    
    # b/17487348
    # Isolated apps can only access three services,
    # activity_service, display_service and webviewupdate_service.
    neverallow isolated_app {
        service_manager_type
        -activity_service
        -display_service
        -webviewupdate_service
    }:service_manager find;
    
    # Isolated apps shouldn't be able to access the driver directly.
    neverallow isolated_app gpu_device:chr_file { rw_file_perms execute };
    
    # Do not allow isolated_app access to /cache
    neverallow isolated_app cache_file:dir ~{ r_dir_perms };
    neverallow isolated_app cache_file:file ~{ read getattr };
    
    # Restrict socket ioctls. Either 1. disallow privileged ioctls, 2. disallow the
    # ioctl permission, or 3. disallow the socket class.
    neverallowxperm isolated_app domain:{ rawip_socket tcp_socket udp_socket } ioctl priv_sock_ioctls;
    neverallow isolated_app *:{ netlink_route_socket netlink_selinux_socket } ioctl;
    neverallow isolated_app *:{
      socket netlink_socket packet_socket key_socket appletalk_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
    } *;
    
    # Do not allow isolated_app to access external storage, except for files passed
    # via file descriptors (b/32896414).
    neverallow isolated_app { storage_file mnt_user_file sdcard_type }:dir ~getattr;
    neverallow isolated_app { storage_file mnt_user_file }:file_class_set *;
    neverallow isolated_app sdcard_type:{ devfile_class_set lnk_file sock_file fifo_file } *;
    neverallow isolated_app sdcard_type:file ~{ read write append getattr lock };
    
    # Do not allow USB access
    neverallow isolated_app { usb_device usbaccessory_device }:chr_file *;
    
    # Restrict the webview_zygote control socket.
    neverallow isolated_app webview_zygote_socket:sock_file write;
    
    # Avoid reads from generically labeled /proc files
    # Create a more specific label if needed
    neverallow isolated_app proc:file { no_rw_file_perms no_x_file_perms };