nixpkgs/nixos/modules/programs/virtualbox-host.nix
aszlig ac603e208c
virtualbox: Fix runtime paths in hardening mode.
Because we have to rely on setuid wrappers on NixOS, we can't easily
hardcode the executable paths and set it 4755. So for all calls, we need
to change the runtime path executable directory to /var/setuid-wrappers/
and for verification we need to retain the executable directory.

Also note, that usually VBoxNetAdpCtl, VBoxNetDHCP, VBoxNetNAT, VBoxSDL
and VBoxVolInfo don't reside in directories that are commonly in PATH,
but in /usr/lib/virtualbox in most mainstream distros. But because the
names of these executables are distinctive enough to not cause
collisions with other setuid programs, I'll leave it like that and not
patch up setuid-wrappers.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>
2014-12-18 14:06:13 +01:00

123 lines
4.2 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
cfg = config.services.virtualboxHost;
virtualbox = config.boot.kernelPackages.virtualbox.override {
inherit (cfg) enableHardening;
};
in
{
options.services.virtualboxHost = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to enable host-side support for VirtualBox.
<note><para>
In order to pass USB devices from the host to the guests, the user
needs to be in the <literal>vboxusers</literal> group.
</para></note>
'';
};
addNetworkInterface = mkOption {
type = types.bool;
default = true;
description = ''
Automatically set up a vboxnet0 host-only network interface.
'';
};
enableHardening = mkOption {
type = types.bool;
default = false;
description = ''
Enable hardened VirtualBox, which ensures that only the binaries in the
system path get access to the devices exposed by the kernel modules
instead of all users in the vboxusers group.
<important><para>
Disabling this can put your system's security at risk, as local users
in the vboxusers group can tamper with the VirtualBox device files.
</para></important>
'';
};
};
config = mkIf cfg.enable (mkMerge [{
boot.kernelModules = [ "vboxdrv" "vboxnetadp" "vboxnetflt" ];
boot.extraModulePackages = [ virtualbox ];
environment.systemPackages = [ virtualbox ];
warnings = mkIf (!cfg.enableHardening) (singleton (
"Hardening is currently disabled for VirtualBox, because of some " +
"issues in conjunction with host-only-interfaces. If you don't use " +
"hostonlyifs, it's strongly recommended to set " +
"`services.virtualboxHost.enableHardening = true'!"
));
security.setuidOwners = let
mkSuid = program: {
inherit program;
source = "${virtualbox}/libexec/virtualbox/${program}";
owner = "root";
group = "vboxusers";
setuid = true;
};
in mkIf cfg.enableHardening (map mkSuid [
"VBoxHeadless"
"VBoxNetAdpCtl"
"VBoxNetDHCP"
"VBoxNetNAT"
"VBoxSDL"
"VBoxVolInfo"
"VirtualBox"
]);
users.extraGroups.vboxusers.gid = config.ids.gids.vboxusers;
services.udev.extraRules =
''
KERNEL=="vboxdrv", OWNER="root", GROUP="vboxusers", MODE="0660", TAG+="systemd"
KERNEL=="vboxdrvu", OWNER="root", GROUP="root", MODE="0666", TAG+="systemd"
KERNEL=="vboxnetctl", OWNER="root", GROUP="vboxusers", MODE="0660", TAG+="systemd"
SUBSYSTEM=="usb_device", ACTION=="add", RUN+="${virtualbox}/libexec/virtualbox/VBoxCreateUSBNode.sh $major $minor $attr{bDeviceClass}"
SUBSYSTEM=="usb", ACTION=="add", ENV{DEVTYPE}=="usb_device", RUN+="${virtualbox}/libexec/virtualbox/VBoxCreateUSBNode.sh $major $minor $attr{bDeviceClass}"
SUBSYSTEM=="usb_device", ACTION=="remove", RUN+="${virtualbox}/libexec/virtualbox/VBoxCreateUSBNode.sh --remove $major $minor"
SUBSYSTEM=="usb", ACTION=="remove", ENV{DEVTYPE}=="usb_device", RUN+="${virtualbox}/libexec/virtualbox/VBoxCreateUSBNode.sh --remove $major $minor"
'';
# Since we lack the right setuid binaries, set up a host-only network by default.
} (mkIf cfg.addNetworkInterface {
systemd.services."vboxnet0" =
{ description = "VirtualBox vboxnet0 Interface";
requires = [ "dev-vboxnetctl.device" ];
after = [ "dev-vboxnetctl.device" ];
wantedBy = [ "network.target" "sys-subsystem-net-devices-vboxnet0.device" ];
path = [ virtualbox ];
serviceConfig.RemainAfterExit = true;
serviceConfig.Type = "oneshot";
serviceConfig.PrivateTmp = true;
environment.VBOX_USER_HOME = "/tmp";
script =
''
if ! [ -e /sys/class/net/vboxnet0 ]; then
VBoxManage hostonlyif create
cat /tmp/VBoxSVC.log >&2
fi
'';
postStop =
''
VBoxManage hostonlyif remove vboxnet0
'';
};
networking.interfaces.vboxnet0.ip4 = [ { address = "192.168.56.1"; prefixLength = 24; } ];
})]);
}