dotfiles/nixos/systems/blowhole/microvms.nix

# SPDX-FileCopyrightText: 2022 Richard Brežák <richard@brezak.sk>
#
# SPDX-License-Identifier: LGPL-3.0-or-later
{ notnft, inputs', lib, config, ... }:
let
  inherit (lib)
    mkBefore
    flip
    genAttrs;
in
{
  networking.notnft = {
    enable = true;
    flush = false;
  };

  networking.notnft.preRules = [
    { add.table = { family = "bridge"; name = "bridge-t"; }; }
    { flush.table = { family = "bridge"; name = "bridge-t"; }; }
  ];

  networking.notnft.rules =
    let
      interfaces = [ "mvm-test" "mvm0" ];
      logRule = with notnft.dsl; with payload; prefix:
          [
            (log { prefix = "${prefix} dropped:  "; flags = (f: [ f.all ]); } )
          ];

      dropRule = with notnft.dsl; with payload;
          [ drop ];
    in
      with notnft.dsl; with payload; ruleset {
        bridge-t = add table { family = f: f.bridge; } {
          input-body = add chain;

          input-mvm = add chain
            [ (vmap ct.state { established = accept; related = accept; invalid = drop; }) ]

            [ (is.eq meta.protocol (f: f.arp)) accept ]
            [ (mangle meta.nftrace 1) ]

            [ (jump "input-body") ]

            (logRule "Bridge input")
            (dropRule);

          input = add chain
            { type = f: f.filter; hook = f: f.input; prio = 0; policy = f: f.accept; }
            [ (vmap meta.iifname (genAttrs interfaces (_: (goto "input-mvm")))) ]
            [ (vmap meta.oifname (genAttrs interfaces (_: (goto "input-mvm")))) ];

          output-body = add chain;

          output-mvm = add chain
            [ (is.eq ether.type (f: f.arp)) accept ]
            [ (mangle meta.nftrace 1) ]

            [ (jump "output-body") ]

            (logRule "Bridge output")
            (dropRule);

          output = add chain
            { type = f: f.filter; hook = f: f.output; prio = 0; policy = f: f.accept; }
            [ (vmap meta.iifname (genAttrs interfaces (_: (goto "output-mvm")))) ]
            [ (vmap meta.oifname (genAttrs interfaces (_: (goto "output-mvm")))) ];


          forward-body = add chain;

          forward-mvm = add chain
            [ (mangle meta.nftrace 1) ]
            [ (jump "forward-body") ]

            (logRule "Bridge forward")
            (dropRule);

          forward = add chain
            { type = f: f.filter; hook = f: f.forward; prio = 0; policy = f: f.accept; }
            [ (vmap meta.iifname (genAttrs interfaces (_: (goto "input-mvm")))) ]
            [ (vmap meta.oifname (genAttrs interfaces (_: (goto "input-mvm")))) ];

          # prerouting = add chain
          #   { type = f: f.filter; hook = f: f.prerouting; prio = -300; policy = f: f.accept; }
          # ;

          # postrouting = add chain
          #   { type = f: f.filter; hook = f: f.postrouting; prio = -300; policy = f: f.accept; }
          # ;
        };
      };

  systemd.services.notnftables = {
    requires = [ "nftables.service" ];
    after = [ "nftables.service" ];
  };

  networking.bridges.mvm0 = {
    interfaces = [];
  };

  networking.interfaces.mvm0 = {
    useDHCP = false;
    ipv4.addresses = [
      {
        address = "10.80.1.1";
        prefixLength = 24;
      }
    ];
  };

  microvm.services.tcpUdp.test-ssh = {
    hostName = "test";
    port = 22;
    protocol = [ "tcp" ];
  };

  microvm.services.tcpUdp.test-http = {
    hostName = "test";
    port = 80;
    protocol = [ "tcp" ];
  };

  microvm.services.icmp.test = {
    hostName = "test";
  };

  microvm.connections.tcpUdp = [
    {
      target = "test-ssh";
    }
    {
      target = "test-http";
    }
  ];
  microvm.connections.icmp = [
    {
      target = "test";
    }
  ];

  microvm.vms = {
    test.config = {
      imports = [ inputs'.self.nixosModules.microvm-extras ];

      microvm = {
        hostName = "test";
        hostsHostName = "omen";
        groupId = 1;
        taskId = 2;
      };

      microvm.hypervisor = "cloud-hypervisor";
      microvm.shares = [{
        source = "/nix/store";
        mountPoint = "/nix/.ro-store";
        tag = "ro-store";
        proto = "virtiofs";
      }];
      microvm.storeOnDisk = false;

      networking.firewall.allowedTCPPorts = [ 80 22 ];

      services.nginx = {
        enable = true;
        virtualHosts."example.com" = {
          root = "/var/www/blog";
        };
      };

      users.users.root.password = "";
      services.getty.helpLine = ''
        Log in as "root" with an empty password.
      '';
      services.openssh = {
        enable = true;
        settings.PermitRootLogin = "yes";
      };
    };
  };
}