depot/nixos/tests/ipv6.nix

# Test of IPv6 functionality in NixOS, including whether router
# solicication/advertisement using radvd works.

import ./make-test-python.nix (
  { pkgs, lib, ... }:
  {
    name = "ipv6";
    meta = with pkgs.lib.maintainers; {
      maintainers = [ ];
    };

    nodes = {
      # We use lib.mkForce here to remove the interface configuration
      # provided by makeTest, so that the interfaces are all configured
      # implicitly.

      # This client should use privacy extensions fully, having a
      # completely-default network configuration.
      client_defaults.networking.interfaces = lib.mkForce { };

      # Both of these clients should obtain temporary addresses, but
      # not use them as the default source IP. We thus run the same
      # checks against them — but the configuration resulting in this
      # behaviour is different.

      # Here, by using an altered default value for the global setting...
      client_global_setting = {
        networking.interfaces = lib.mkForce { };
        networking.tempAddresses = "enabled";
      };
      # and here, by setting this on the interface explicitly.
      client_interface_setting = {
        networking.tempAddresses = "disabled";
        networking.interfaces = lib.mkForce {
          eth1.tempAddress = "enabled";
        };
      };

      server = {
        services.httpd.enable = true;
        services.httpd.adminAddr = "foo@example.org";
        networking.firewall.allowedTCPPorts = [ 80 ];
        # disable testing driver's default IPv6 address.
        networking.interfaces.eth1.ipv6.addresses = lib.mkForce [ ];
      };

      router =
        { ... }:
        {
          services.radvd.enable = true;
          services.radvd.config = ''
            interface eth1 {
              AdvSendAdvert on;
              # ULA prefix (RFC 4193).
              prefix fd60:cc69:b537:1::/64 { };
            };
          '';
        };
    };

    testScript = ''
      import re

      # Start the router first so that it respond to router solicitations.
      router.wait_for_unit("radvd")

      clients = [client_defaults, client_global_setting, client_interface_setting]

      start_all()

      for client in clients:
          client.wait_for_unit("network.target")
      server.wait_for_unit("network.target")
      server.wait_for_unit("httpd.service")

      # Wait until the given interface has a non-tentative address of
      # the desired scope (i.e. has completed Duplicate Address
      # Detection).
      def wait_for_address(machine, iface, scope, temporary=False):
          temporary_flag = "temporary" if temporary else "-temporary"
          cmd = f"ip -o -6 addr show dev {iface} scope {scope} -tentative {temporary_flag}"

          machine.wait_until_succeeds(f"[ `{cmd} | wc -l` -eq 1 ]")
          output = machine.succeed(cmd)
          ip = re.search(r"inet6 ([0-9a-f:]{2,})/", output).group(1)

          if temporary:
              scope = scope + " temporary"
          machine.log(f"{scope} address on {iface} is {ip}")
          return ip


      with subtest("Loopback address can be pinged"):
          client_defaults.succeed("ping -c 1 ::1 >&2")
          client_defaults.fail("ping -c 1 2001:db8:: >&2")

      with subtest("Local link addresses can be obtained and pinged"):
          for client in clients:
              client_ip = wait_for_address(client, "eth1", "link")
              server_ip = wait_for_address(server, "eth1", "link")
              client.succeed(f"ping -c 1 {client_ip}%eth1 >&2")
              client.succeed(f"ping -c 1 {server_ip}%eth1 >&2")

      with subtest("Global addresses can be obtained, pinged, and reached via http"):
          for client in clients:
              client_ip = wait_for_address(client, "eth1", "global")
              server_ip = wait_for_address(server, "eth1", "global")
              client.succeed(f"ping -c 1 {client_ip} >&2")
              client.succeed(f"ping -c 1 {server_ip} >&2")
              client.succeed(f"curl --fail -g http://[{server_ip}]")
              client.fail(f"curl --fail -g http://[{client_ip}]")

      with subtest(
          "Privacy extensions: Global temporary address is used as default source address"
      ):
          ip = wait_for_address(client_defaults, "eth1", "global", temporary=True)
          # Default route should have "src <temporary address>" in it
          client_defaults.succeed(f"ip route get 2001:db8:: | grep 'src {ip}'")

      for client, setting_desc in (
          (client_global_setting, "global"),
          (client_interface_setting, "interface"),
      ):
          with subtest(f'Privacy extensions: "enabled" through {setting_desc} setting)'):
              # We should be obtaining both a temporary address and an EUI-64 address...
              ip = wait_for_address(client, "eth1", "global")
              assert "ff:fe" in ip
              ip_temp = wait_for_address(client, "eth1", "global", temporary=True)
              # But using the EUI-64 one.
              client.succeed(f"ip route get 2001:db8:: | grep 'src {ip}'")
    '';
  }
)