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|
{ config, lib, pkgs, ... }:
with lib;
let
gce = pkgs.google-compute-engine;
in
{
imports = [
./headless.nix
./qemu-guest.nix
];
fileSystems."/" = {
device = "/dev/disk/by-label/nixos";
autoResize = true;
};
boot.growPartition = true;
boot.kernelParams = [ "console=ttyS0" "panic=1" "boot.panic_on_fail" ];
boot.initrd.kernelModules = [ "virtio_scsi" ];
boot.kernelModules = [ "virtio_pci" "virtio_net" ];
# Generate a GRUB menu. Amazon's pv-grub uses this to boot our kernel/initrd.
boot.loader.grub.device = "/dev/sda";
boot.loader.timeout = 0;
# Don't put old configurations in the GRUB menu. The user has no
# way to select them anyway.
boot.loader.grub.configurationLimit = 0;
# Allow root logins only using the SSH key that the user specified
# at instance creation time.
#services.openssh.enable = true;
#services.openssh.permitRootLogin = "prohibit-password";
#services.openssh.passwordAuthentication = mkDefault false;
# Use GCE udev rules for dynamic disk volumes
services.udev.packages = [ gce ];
# Force getting the hostname from Google Compute.
networking.hostName = mkDefault "";
# Always include cryptsetup so that NixOps can use it.
environment.systemPackages = [ pkgs.cryptsetup ];
# Make sure GCE image does not replace host key that NixOps sets
environment.etc."default/instance_configs.cfg".text = lib.mkDefault ''
[InstanceSetup]
set_host_keys = false
'';
# Rely on GCP's firewall instead
networking.firewall.enable = mkDefault false;
# Configure default metadata hostnames
networking.extraHosts = ''
169.254.169.254 metadata.google.internal metadata
'';
networking.timeServers = [ "metadata.google.internal" ];
networking.usePredictableInterfaceNames = false;
# GC has 1460 MTU
networking.interfaces.eth0.mtu = 1460;
security.googleOsLogin.enable = true;
systemd.services.google-clock-skew-daemon = {
description = "Google Compute Engine Clock Skew Daemon";
after = [
"network.target"
"google-instance-setup.service"
"google-network-setup.service"
];
requires = ["network.target"];
wantedBy = ["multi-user.target"];
serviceConfig = {
Type = "simple";
ExecStart = "${gce}/bin/google_clock_skew_daemon --debug";
};
};
systemd.services.google-instance-setup = {
description = "Google Compute Engine Instance Setup";
after = ["local-fs.target" "network-online.target" "network.target" "rsyslog.service"];
before = ["sshd.service"];
wants = ["local-fs.target" "network-online.target" "network.target"];
wantedBy = [ "sshd.service" "multi-user.target" ];
path = with pkgs; [ ethtool openssh ];
serviceConfig = {
ExecStart = "${gce}/bin/google_instance_setup --debug";
Type = "oneshot";
};
};
systemd.services.google-network-daemon = {
description = "Google Compute Engine Network Daemon";
after = ["local-fs.target" "network-online.target" "network.target" "rsyslog.service" "google-instance-setup.service"];
wants = ["local-fs.target" "network-online.target" "network.target"];
requires = ["network.target"];
partOf = ["network.target"];
wantedBy = [ "multi-user.target" ];
path = with pkgs; [ iproute ];
serviceConfig = {
ExecStart = "${gce}/bin/google_network_daemon --debug";
};
};
systemd.services.google-shutdown-scripts = {
description = "Google Compute Engine Shutdown Scripts";
after = [
"local-fs.target"
"network-online.target"
"network.target"
"rsyslog.service"
"systemd-resolved.service"
"google-instance-setup.service"
"google-network-daemon.service"
];
wants = [ "local-fs.target" "network-online.target" "network.target"];
wantedBy = [ "multi-user.target" ];
serviceConfig = {
ExecStart = "${pkgs.coreutils}/bin/true";
ExecStop = "${gce}/bin/google_metadata_script_runner --debug --script-type shutdown";
Type = "oneshot";
RemainAfterExit = true;
TimeoutStopSec = "infinity";
};
};
systemd.services.google-startup-scripts = {
description = "Google Compute Engine Startup Scripts";
after = [
"local-fs.target"
"network-online.target"
"network.target"
"rsyslog.service"
"google-instance-setup.service"
"google-network-daemon.service"
];
wants = ["local-fs.target" "network-online.target" "network.target"];
wantedBy = [ "multi-user.target" ];
serviceConfig = {
ExecStart = "${gce}/bin/google_metadata_script_runner --debug --script-type startup";
KillMode = "process";
Type = "oneshot";
};
};
# Settings taken from https://github.com/GoogleCloudPlatform/compute-image-packages/blob/master/google_config/sysctl/11-gce-network-security.conf
boot.kernel.sysctl = {
# Turn on SYN-flood protections. Starting with 2.6.26, there is no loss
# of TCP functionality/features under normal conditions. When flood
# protections kick in under high unanswered-SYN load, the system
# should remain more stable, with a trade off of some loss of TCP
# functionality/features (e.g. TCP Window scaling).
"net.ipv4.tcp_syncookies" = mkDefault "1";
# ignores source-routed packets
"net.ipv4.conf.all.accept_source_route" = mkDefault "0";
# ignores source-routed packets
"net.ipv4.conf.default.accept_source_route" = mkDefault "0";
# ignores ICMP redirects
"net.ipv4.conf.all.accept_redirects" = mkDefault "0";
# ignores ICMP redirects
"net.ipv4.conf.default.accept_redirects" = mkDefault "0";
# ignores ICMP redirects from non-GW hosts
"net.ipv4.conf.all.secure_redirects" = mkDefault "1";
# ignores ICMP redirects from non-GW hosts
"net.ipv4.conf.default.secure_redirects" = mkDefault "1";
# don't allow traffic between networks or act as a router
"net.ipv4.ip_forward" = mkDefault "0";
# don't allow traffic between networks or act as a router
"net.ipv4.conf.all.send_redirects" = mkDefault "0";
# don't allow traffic between networks or act as a router
"net.ipv4.conf.default.send_redirects" = mkDefault "0";
# reverse path filtering - IP spoofing protection
"net.ipv4.conf.all.rp_filter" = mkDefault "1";
# reverse path filtering - IP spoofing protection
"net.ipv4.conf.default.rp_filter" = mkDefault "1";
# ignores ICMP broadcasts to avoid participating in Smurf attacks
"net.ipv4.icmp_echo_ignore_broadcasts" = mkDefault "1";
# ignores bad ICMP errors
"net.ipv4.icmp_ignore_bogus_error_responses" = mkDefault "1";
# logs spoofed, source-routed, and redirect packets
"net.ipv4.conf.all.log_martians" = mkDefault "1";
# log spoofed, source-routed, and redirect packets
"net.ipv4.conf.default.log_martians" = mkDefault "1";
# implements RFC 1337 fix
"net.ipv4.tcp_rfc1337" = mkDefault "1";
# randomizes addresses of mmap base, heap, stack and VDSO page
"kernel.randomize_va_space" = mkDefault "2";
# Reboot the machine soon after a kernel panic.
"kernel.panic" = mkDefault "10";
## Not part of the original config
# provides protection from ToCToU races
"fs.protected_hardlinks" = mkDefault "1";
# provides protection from ToCToU races
"fs.protected_symlinks" = mkDefault "1";
# makes locating kernel addresses more difficult
"kernel.kptr_restrict" = mkDefault "1";
# set ptrace protections
"kernel.yama.ptrace_scope" = mkOverride 500 "1";
# set perf only available to root
"kernel.perf_event_paranoid" = mkDefault "2";
};
}
|
