nixos/nebula: Add nebula unit test

nixos/tests/nebula.nix

@@ -0,0 +1,132 @@
+import ./make-test-python.nix ({ pkgs, lib, ... }: let
+
+  # We'll need to be able to trade cert files between nodes via scp.
+  inherit (import ./ssh-keys.nix pkgs)
+    snakeOilPrivateKey snakeOilPublicKey;
+
+  makeNebulaNode = { config, ... }: name: extraConfig: lib.mkMerge [
+    {
+      # Expose nebula for doing cert signing.
+      environment.systemPackages = [ pkgs.nebula ];
+      users.users.root.openssh.authorizedKeys.keys = [ snakeOilPublicKey ];
+      services.openssh.enable = true;
+
+      services.nebula.networks.smoke = {
+        # Note that these paths won't exist when the machine is first booted.
+        ca = "/etc/nebula/ca.crt";
+        cert = "/etc/nebula/${name}.crt";
+        key = "/etc/nebula/${name}.key";
+        listen = { host = "0.0.0.0"; port = 4242; };
+      };
+    }
+    extraConfig
+  ];
+
+in
+{
+  name = "nebula";
+
+  nodes = {
+
+    lighthouse = { ... } @ args:
+      makeNebulaNode args "lighthouse" {
+        networking.interfaces.eth1.ipv4.addresses = [{
+          address = "192.168.1.1";
+          prefixLength = 24;
+        }];
+
+        services.nebula.networks.smoke = {
+          isLighthouse = true;
+          firewall = {
+            outbound = [ { port = "any"; proto = "any"; host = "any"; } ];
+            inbound = [ { port = "any"; proto = "any"; host = "any"; } ];
+          };
+        };
+      };
+
+    node2 = { ... } @ args:
+      makeNebulaNode args "node2" {
+        networking.interfaces.eth1.ipv4.addresses = [{
+          address = "192.168.1.2";
+          prefixLength = 24;
+        }];
+
+        services.nebula.networks.smoke = {
+          staticHostMap = { "10.0.100.1" = [ "192.168.1.1:4242" ]; };
+          isLighthouse = false;
+          lighthouses = [ "10.0.100.1" ];
+          firewall = {
+            outbound = [ { port = "any"; proto = "any"; host = "any"; } ];
+            inbound = [ { port = "any"; proto = "any"; host = "any"; } ];
+          };
+        };
+      };
+
+  };
+
+  testScript = let
+
+    setUpPrivateKey = name: ''
+    ${name}.succeed(
+        "mkdir -p /root/.ssh",
+        "chown 700 /root/.ssh",
+        "cat '${snakeOilPrivateKey}' > /root/.ssh/id_snakeoil",
+        "chown 600 /root/.ssh/id_snakeoil",
+    )
+    '';
+
+    # From what I can tell, StrictHostKeyChecking=no is necessary for ssh to work between machines.
+    sshOpts = "-oStrictHostKeyChecking=no -oUserKnownHostsFile=/dev/null -oIdentityFile=/root/.ssh/id_snakeoil";
+
+    restartAndCheckNebula = name: ip: ''
+      ${name}.systemctl("restart nebula@smoke.service")
+      ${name}.succeed("ping -c5 ${ip}")
+    '';
+
+    # Create a keypair on the client node, then use the public key to sign a cert on the lighthouse.
+    signKeysFor = name: ip: ''
+      lighthouse.wait_for_unit("sshd.service")
+      ${name}.wait_for_unit("sshd.service")
+      ${name}.succeed(
+          "mkdir -p /etc/nebula",
+          "nebula-cert keygen -out-key /etc/nebula/${name}.key -out-pub /etc/nebula/${name}.pub",
+          "scp ${sshOpts} /etc/nebula/${name}.pub 192.168.1.1:/tmp/${name}.pub",
+      )
+      lighthouse.succeed(
+          'nebula-cert sign -ca-crt /etc/nebula/ca.crt -ca-key /etc/nebula/ca.key -name "${name}" -groups "${name}" -ip "${ip}" -in-pub /tmp/${name}.pub -out-crt /tmp/${name}.crt',
+      )
+      ${name}.succeed(
+          "scp ${sshOpts} 192.168.1.1:/tmp/${name}.crt /etc/nebula/${name}.crt",
+          "scp ${sshOpts} 192.168.1.1:/etc/nebula/ca.crt /etc/nebula/ca.crt",
+      )
+    '';
+
+  in ''
+    start_all()
+
+    # Create the certificate and sign the lighthouse's keys.
+    ${setUpPrivateKey "lighthouse"}
+    lighthouse.succeed(
+        "mkdir -p /etc/nebula",
+        'nebula-cert ca -name "Smoke Test" -out-crt /etc/nebula/ca.crt -out-key /etc/nebula/ca.key',
+        'nebula-cert sign -ca-crt /etc/nebula/ca.crt -ca-key /etc/nebula/ca.key -name "lighthouse" -groups "lighthouse" -ip "10.0.100.1/24" -out-crt /etc/nebula/lighthouse.crt -out-key /etc/nebula/lighthouse.key',
+    )
+
+    # Reboot the lighthouse and verify that the nebula service comes up on boot.
+    # Since rebooting takes a while, we'll just restart the service on the other nodes.
+    lighthouse.shutdown()
+    lighthouse.start()
+    lighthouse.wait_for_unit("nebula@smoke.service")
+    lighthouse.succeed("ping -c5 10.0.100.1")
+
+    # Create keys on node2 and have the lighthouse sign them.
+    ${setUpPrivateKey "node2"}
+    ${signKeysFor "node2" "10.0.100.2/24"}
+
+    # Reboot node2 and test that the nebula service comes up.
+    ${restartAndCheckNebula "node2" "10.0.100.2"}
+
+    # Test that the node is now connected to the lighthouse.
+    node2.succeed("ping -c5 10.0.100.1")
+  '';
+})