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|
import ./make-test.nix ({ pkgs, ...} : {
name = "hardened";
meta = with pkgs.stdenv.lib.maintainers; {
maintainers = [ joachifm ];
};
machine =
{ lib, pkgs, config, ... }:
with lib;
{ users.users.alice = { isNormalUser = true; extraGroups = [ "proc" ]; };
users.users.sybil = { isNormalUser = true; group = "wheel"; };
imports = [ ../modules/profiles/hardened.nix ];
environment.memoryAllocator.provider = "graphene-hardened";
nix.useSandbox = false;
virtualisation.emptyDiskImages = [ 4096 ];
boot.initrd.postDeviceCommands = ''
${pkgs.dosfstools}/bin/mkfs.vfat -n EFISYS /dev/vdb
'';
fileSystems = lib.mkVMOverride {
"/efi" = {
device = "/dev/disk/by-label/EFISYS";
fsType = "vfat";
options = [ "noauto" ];
};
};
boot.extraModulePackages = [ config.boot.kernelPackages.wireguard ];
boot.kernelModules = [ "wireguard" ];
};
testScript =
let
hardened-malloc-tests = pkgs.stdenv.mkDerivation {
name = "hardened-malloc-tests-${pkgs.graphene-hardened-malloc.version}";
src = pkgs.graphene-hardened-malloc.src;
buildPhase = ''
cd test/simple-memory-corruption
make -j4
'';
installPhase = ''
find . -type f -executable -exec install -Dt $out/bin '{}' +
'';
};
in
''
$machine->waitForUnit("multi-user.target");
subtest "apparmor-loaded", sub {
$machine->succeed("systemctl status apparmor.service");
};
# AppArmor securityfs
subtest "apparmor-securityfs", sub {
$machine->succeed("mountpoint -q /sys/kernel/security");
$machine->succeed("cat /sys/kernel/security/apparmor/profiles");
};
# Test loading out-of-tree modules
subtest "extra-module-packages", sub {
$machine->succeed("grep -Fq wireguard /proc/modules");
};
# Test hidepid
subtest "hidepid", sub {
$machine->succeed("grep -Fq hidepid=2 /proc/mounts");
# cannot use pgrep -u here, it segfaults when access to process info is denied
$machine->succeed("[ `su - sybil -c 'ps --no-headers --user root | wc -l'` = 0 ]");
$machine->succeed("[ `su - alice -c 'ps --no-headers --user root | wc -l'` != 0 ]");
};
# Test kernel module hardening
subtest "lock-modules", sub {
# note: this better a be module we normally wouldn't load ...
$machine->fail("modprobe dccp");
};
# Test userns
subtest "userns", sub {
$machine->fail("unshare --user");
};
# Test dmesg restriction
subtest "dmesg", sub {
$machine->fail("su -l alice -c dmesg");
};
# Test access to kcore
subtest "kcore", sub {
$machine->fail("cat /proc/kcore");
};
# Test deferred mount
subtest "mount", sub {
$machine->fail("mountpoint -q /efi"); # was deferred
$machine->execute("mkdir -p /efi");
$machine->succeed("mount /dev/disk/by-label/EFISYS /efi");
$machine->succeed("mountpoint -q /efi"); # now mounted
};
# Test Nix dæmon usage
subtest "nix-daemon", sub {
$machine->fail("su -l nobody -s /bin/sh -c 'nix ping-store'");
$machine->succeed("su -l alice -c 'nix ping-store'") =~ "OK";
};
# Test kernel image protection
subtest "kernelimage", sub {
$machine->fail("systemctl hibernate");
$machine->fail("systemctl kexec");
};
# Test hardened memory allocator
sub runMallocTestProg {
my ($progName, $errorText) = @_;
my $text = "fatal allocator error: " . $errorText;
$machine->fail("${hardened-malloc-tests}/bin/" . $progName) =~ $text;
};
subtest "hardenedmalloc", sub {
runMallocTestProg("double_free_large", "invalid free");
runMallocTestProg("unaligned_free_small", "invalid unaligned free");
runMallocTestProg("write_after_free_small", "detected write after free");
};
'';
})
|