feat: add node address filters, filter out k8s addresses for Talos API

This implements abstract `NodeAddressFilter` which can be attached to
build additional `NodeAddress` resources filtering out some entries from
the complete list.

Kubernetes creates two filters to get all node IPs without Kubernetes
CIDRs and vice versa, only Kubernetes CIDRs.

API certificate generation now considers all addresses minus K8s CIDRs.

Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>

internal/app/machined/pkg/controllers/config/k8s_address_filter.go

@@ -0,0 +1,129 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package config
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/AlekSi/pointer"
+	"github.com/cosi-project/runtime/pkg/controller"
+	"github.com/cosi-project/runtime/pkg/resource"
+	"github.com/cosi-project/runtime/pkg/state"
+	"go.uber.org/zap"
+	"inet.af/netaddr"
+
+	"github.com/talos-systems/talos/pkg/resources/config"
+	"github.com/talos-systems/talos/pkg/resources/k8s"
+	"github.com/talos-systems/talos/pkg/resources/network"
+)
+
+// K8sAddressFilterController creates NodeAddressFilters based on machine configuration.
+type K8sAddressFilterController struct{}
+
+// Name implements controller.Controller interface.
+func (ctrl *K8sAddressFilterController) Name() string {
+	return "network.K8sAddressFilterController"
+}
+
+// Inputs implements controller.Controller interface.
+func (ctrl *K8sAddressFilterController) Inputs() []controller.Input {
+	return []controller.Input{
+		{
+			Namespace: config.NamespaceName,
+			Type:      config.MachineConfigType,
+			ID:        pointer.ToString(config.V1Alpha1ID),
+			Kind:      controller.InputWeak,
+		},
+	}
+}
+
+// Outputs implements controller.Controller interface.
+func (ctrl *K8sAddressFilterController) Outputs() []controller.Output {
+	return []controller.Output{
+		{
+			Type: network.NodeAddressFilterType,
+			Kind: controller.OutputExclusive,
+		},
+	}
+}
+
+// Run implements controller.Controller interface.
+//
+//nolint:gocyclo
+func (ctrl *K8sAddressFilterController) Run(ctx context.Context, r controller.Runtime, logger *zap.Logger) error {
+	for {
+		select {
+		case <-ctx.Done():
+			return nil
+		case <-r.EventCh():
+		}
+
+		cfg, err := r.Get(ctx, resource.NewMetadata(config.NamespaceName, config.MachineConfigType, config.V1Alpha1ID, resource.VersionUndefined))
+		if err != nil && !state.IsNotFoundError(err) {
+			return fmt.Errorf("error getting config: %w", err)
+		}
+
+		touchedIDs := make(map[resource.ID]struct{})
+
+		if cfg != nil {
+			cfgProvider := cfg.(*config.MachineConfig).Config()
+
+			var podCIDR, serviceCIDR netaddr.IPPrefix
+
+			podCIDR, err = netaddr.ParseIPPrefix(cfgProvider.Cluster().Network().PodCIDR())
+			if err != nil {
+				return fmt.Errorf("error parsing podCIDR: %w", err)
+			}
+
+			serviceCIDR, err = netaddr.ParseIPPrefix(cfgProvider.Cluster().Network().ServiceCIDR())
+			if err != nil {
+				return fmt.Errorf("error parsing serviceCIDR: %w", err)
+			}
+
+			if err = r.Modify(ctx, network.NewNodeAddressFilter(network.NamespaceName, k8s.NodeAddressFilterNoK8s), func(r resource.Resource) error {
+				spec := r.(*network.NodeAddressFilter).TypedSpec()
+
+				spec.ExcludeSubnets = []netaddr.IPPrefix{podCIDR, serviceCIDR}
+
+				return nil
+			}); err != nil {
+				return fmt.Errorf("error updating output resource: %w", err)
+			}
+
+			touchedIDs[k8s.NodeAddressFilterNoK8s] = struct{}{}
+
+			if err = r.Modify(ctx, network.NewNodeAddressFilter(network.NamespaceName, k8s.NodeAddressFilterOnlyK8s), func(r resource.Resource) error {
+				spec := r.(*network.NodeAddressFilter).TypedSpec()
+
+				spec.IncludeSubnets = []netaddr.IPPrefix{podCIDR, serviceCIDR}
+
+				return nil
+			}); err != nil {
+				return fmt.Errorf("error updating output resource: %w", err)
+			}
+
+			touchedIDs[k8s.NodeAddressFilterOnlyK8s] = struct{}{}
+		}
+
+		// list keys for cleanup
+		list, err := r.List(ctx, resource.NewMetadata(network.NamespaceName, network.NodeAddressFilterType, "", resource.VersionUndefined))
+		if err != nil {
+			return fmt.Errorf("error listing resources: %w", err)
+		}
+
+		for _, res := range list.Items {
+			if res.Metadata().Owner() != ctrl.Name() {
+				continue
+			}
+
+			if _, ok := touchedIDs[res.Metadata().ID()]; !ok {
+				if err = r.Destroy(ctx, res.Metadata()); err != nil {
+					return fmt.Errorf("error cleaning up specs: %w", err)
+				}
+			}
+		}
+	}
+}

internal/app/machined/pkg/controllers/config/k8s_address_filter_test.go

@@ -0,0 +1,149 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+//nolint:dupl
+package config_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"net/url"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/cosi-project/runtime/pkg/controller/runtime"
+	"github.com/cosi-project/runtime/pkg/resource"
+	"github.com/cosi-project/runtime/pkg/state"
+	"github.com/cosi-project/runtime/pkg/state/impl/inmem"
+	"github.com/cosi-project/runtime/pkg/state/impl/namespaced"
+	"github.com/stretchr/testify/suite"
+	"github.com/talos-systems/go-retry/retry"
+
+	configctrl "github.com/talos-systems/talos/internal/app/machined/pkg/controllers/config"
+	"github.com/talos-systems/talos/pkg/logging"
+	"github.com/talos-systems/talos/pkg/machinery/config/types/v1alpha1"
+	"github.com/talos-systems/talos/pkg/resources/config"
+	"github.com/talos-systems/talos/pkg/resources/k8s"
+	"github.com/talos-systems/talos/pkg/resources/network"
+)
+
+type K8sAddressFilterSuite struct {
+	suite.Suite
+
+	state state.State
+
+	runtime *runtime.Runtime
+	wg      sync.WaitGroup
+
+	ctx       context.Context
+	ctxCancel context.CancelFunc
+}
+
+func (suite *K8sAddressFilterSuite) SetupTest() {
+	suite.ctx, suite.ctxCancel = context.WithTimeout(context.Background(), 3*time.Minute)
+
+	suite.state = state.WrapCore(namespaced.NewState(inmem.Build))
+
+	var err error
+
+	suite.runtime, err = runtime.NewRuntime(suite.state, logging.Wrap(log.Writer()))
+	suite.Require().NoError(err)
+
+	suite.Require().NoError(suite.runtime.RegisterController(&configctrl.K8sAddressFilterController{}))
+
+	suite.startRuntime()
+}
+
+func (suite *K8sAddressFilterSuite) startRuntime() {
+	suite.wg.Add(1)
+
+	go func() {
+		defer suite.wg.Done()
+
+		suite.Assert().NoError(suite.runtime.Run(suite.ctx))
+	}()
+}
+
+func (suite *K8sAddressFilterSuite) assertResource(md resource.Metadata, check func(res resource.Resource) error) func() error {
+	return func() error {
+		r, err := suite.state.Get(suite.ctx, md)
+		if err != nil {
+			if state.IsNotFoundError(err) {
+				return retry.ExpectedError(err)
+			}
+
+			return err
+		}
+
+		return check(r)
+	}
+}
+
+func (suite *K8sAddressFilterSuite) TestReconcile() {
+	u, err := url.Parse("https://foo:6443")
+	suite.Require().NoError(err)
+
+	cfg := config.NewMachineConfig(&v1alpha1.Config{
+		ConfigVersion: "v1alpha1",
+		MachineConfig: &v1alpha1.MachineConfig{},
+		ClusterConfig: &v1alpha1.ClusterConfig{
+			ControlPlane: &v1alpha1.ControlPlaneConfig{
+				Endpoint: &v1alpha1.Endpoint{
+					URL: u,
+				},
+			},
+			ClusterNetwork: &v1alpha1.ClusterNetworkConfig{
+				ServiceSubnet: []string{
+					"10.96.0.0/12",
+				},
+				PodSubnet: []string{
+					"10.244.0.0/12",
+				},
+			},
+		},
+	})
+	suite.Require().NoError(suite.state.Create(suite.ctx, cfg))
+
+	suite.Assert().NoError(retry.Constant(3*time.Second, retry.WithUnits(100*time.Millisecond)).Retry(
+		suite.assertResource(
+			resource.NewMetadata(network.NamespaceName, network.NodeAddressFilterType, k8s.NodeAddressFilterOnlyK8s, resource.VersionUndefined),
+			func(res resource.Resource) error {
+				spec := res.(*network.NodeAddressFilter).TypedSpec()
+
+				suite.Assert().Equal("[10.244.0.0/12 10.96.0.0/12]", fmt.Sprintf("%s", spec.IncludeSubnets))
+				suite.Assert().Empty(spec.ExcludeSubnets)
+
+				return nil
+			},
+		),
+	))
+
+	suite.Assert().NoError(retry.Constant(3*time.Second, retry.WithUnits(100*time.Millisecond)).Retry(
+		suite.assertResource(
+			resource.NewMetadata(network.NamespaceName, network.NodeAddressFilterType, k8s.NodeAddressFilterNoK8s, resource.VersionUndefined),
+			func(res resource.Resource) error {
+				spec := res.(*network.NodeAddressFilter).TypedSpec()
+
+				suite.Assert().Empty(spec.IncludeSubnets)
+				suite.Assert().Equal("[10.244.0.0/12 10.96.0.0/12]", fmt.Sprintf("%s", spec.ExcludeSubnets))
+
+				return nil
+			},
+		),
+	))
+}
+
+func (suite *K8sAddressFilterSuite) TearDownTest() {
+	suite.T().Log("tear down")
+
+	suite.ctxCancel()
+
+	suite.wg.Wait()
+}
+
+func TestK8sAddressFilterSuite(t *testing.T) {
+	suite.Run(t, new(K8sAddressFilterSuite))
+}

internal/app/machined/pkg/controllers/config/k8s_control_plane_test.go

@@ -2,6 +2,7 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
+//nolint:dupl
 package config_test
 
 import (