feat: add CNI, and pod and service CIDR to configurator

This adds more methods to the Cluster interface that allows for more
granular control of the cluster network settings.

Signed-off-by: Andrew Rynhard <andrew@andrewrynhard.com>

internal/app/machined/pkg/system/services/bootkube.go

@@ -23,6 +23,7 @@ import (
 	"github.com/talos-systems/talos/internal/app/machined/pkg/system/runner/goroutine"
 	"github.com/talos-systems/talos/pkg/config"
 	"github.com/talos-systems/talos/pkg/constants"
+	tnet "github.com/talos-systems/talos/pkg/net"
 )
 
 // Bootkube implements the Service interface. It serves as the concrete type with
@@ -125,11 +126,11 @@ func generateAssets(config config.Configurator) (err error) {
 	}
 	apiServers = append(apiServers, u)
 
-	_, podCIDR, err := net.ParseCIDR("10.2.0.0/16")
+	_, podCIDR, err := net.ParseCIDR(config.Cluster().Network().PodCIDR())
 	if err != nil {
 		return err
 	}
-	_, serviceCIDR, err := net.ParseCIDR("10.3.0.0/24")
+	_, serviceCIDR, err := net.ParseCIDR(config.Cluster().Network().ServiceCIDR())
 	if err != nil {
 		return err
 	}
@@ -154,6 +155,16 @@ func generateAssets(config config.Configurator) (err error) {
 		return errors.Wrap(err, "failed to parse Kubernetes key")
 	}
 
+	apiServiceIP, err := tnet.NthIPInNetwork(serviceCIDR, 1)
+	if err != nil {
+		return err
+	}
+
+	dnsServiceIP, err := tnet.NthIPInNetwork(serviceCIDR, 10)
+	if err != nil {
+		return err
+	}
+
 	conf := asset.Config{
 		CACert:                 k8sCA,
 		CAPrivKey:              k8sKey,
@@ -163,11 +174,11 @@ func generateAssets(config config.Configurator) (err error) {
 		EtcdServers:            []*url.URL{etcdServer},
 		EtcdUseTLS:             true,
 		APIServers:             apiServers,
-		APIServiceIP:           net.ParseIP("10.3.0.1"),
-		DNSServiceIP:           net.ParseIP("10.3.0.10"),
+		APIServiceIP:           apiServiceIP,
+		DNSServiceIP:           dnsServiceIP,
 		PodCIDR:                podCIDR,
 		ServiceCIDR:            serviceCIDR,
-		NetworkProvider:        "flannel",
+		NetworkProvider:        config.Cluster().Network().CNI(),
 		AltNames:               altNames,
 		Images:                 asset.DefaultImages,
 		BootstrapSecretsSubdir: "/assets/tls",

pkg/config/cluster/cluster.go

@@ -20,6 +20,15 @@ type Cluster interface {
 	AESCBCEncryptionSecret() string
 	Config(machine.Type) (string, error)
 	Etcd() Etcd
+	Network() Network
+}
+
+// Network defines the requirements for a config that pertains to cluster
+// network options.
+type Network interface {
+	CNI() string
+	PodCIDR() string
+	ServiceCIDR() string
 }
 
 // Etcd defines the requirements for a config that pertains to etcd related

pkg/config/types/v1alpha1/cluster_config.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/talos-systems/talos/pkg/config/cluster"
 	"github.com/talos-systems/talos/pkg/config/machine"
+	"github.com/talos-systems/talos/pkg/constants"
 	"github.com/talos-systems/talos/pkg/crypto/x509"
 )
 
@@ -16,7 +17,7 @@ import (
 type ClusterConfig struct {
 	ControlPlane                  *ControlPlaneConfig               `yaml:"controlPlane"`
 	ClusterName                   string                            `yaml:"clusterName,omitempty"`
-	Network                       *ClusterNetworkConfig             `yaml:"network,omitempty"`
+	ClusterNetwork                *ClusterNetworkConfig             `yaml:"network,omitempty"`
 	BootstrapToken                string                            `yaml:"token,omitempty"`
 	CertificateKey                string                            `yaml:"certificateKey"`
 	ClusterAESCBCEncryptionSecret string                            `yaml:"aescbcEncryptionSecret"`
@@ -67,6 +68,7 @@ type EtcdConfig struct {
 
 // ClusterNetworkConfig represents kube networking config vals
 type ClusterNetworkConfig struct {
+	CNI           string   `yaml:"cni"`
 	DNSDomain     string   `yaml:"dnsDomain"`
 	PodSubnet     []string `yaml:"podSubnets"`
 	ServiceSubnet []string `yaml:"serviceSubnets"`
@@ -139,3 +141,35 @@ func (c *ClusterConfig) Secret() string {
 	}
 	return parts[1]
 }
+
+// Network implements the Configurator interface.
+func (c *ClusterConfig) Network() cluster.Network {
+	return c
+}
+
+// CNI implements the Configurator interface.
+func (c *ClusterConfig) CNI() string {
+	if c.ClusterNetwork.CNI == "" {
+		return constants.DefaultCNI
+	}
+
+	return c.ClusterNetwork.CNI
+}
+
+// PodCIDR implements the Configurator interface.
+func (c *ClusterConfig) PodCIDR() string {
+	if len(c.ClusterNetwork.PodSubnet) == 0 {
+		return constants.DefaultPodCIDR
+	}
+
+	return c.ClusterNetwork.PodSubnet[0]
+}
+
+// ServiceCIDR implements the Configurator interface.
+func (c *ClusterConfig) ServiceCIDR() string {
+	if len(c.ClusterNetwork.ServiceSubnet) == 0 {
+		return constants.DefaultServiceCIDR
+	}
+
+	return c.ClusterNetwork.ServiceSubnet[0]
+}

pkg/config/types/v1alpha1/generate/init.go

@@ -37,7 +37,7 @@ func initUd(in *Input) (string, error) {
 		EtcdConfig: &v1alpha1.EtcdConfig{
 			RootCA: in.Certs.Etcd,
 		},
-		Network: &v1alpha1.ClusterNetworkConfig{
+		ClusterNetwork: &v1alpha1.ClusterNetworkConfig{
 			DNSDomain:     in.ServiceDomain,
 			PodSubnet:     in.PodNet,
 			ServiceSubnet: in.ServiceNet,

pkg/constants/constants.go

@@ -233,6 +233,15 @@ const (
 
 	// DefaultLogPath is the default path to the log storage directory.
 	DefaultLogPath = SystemRunPath + "/log"
+
+	// DefaultCNI is the default CNI.
+	DefaultCNI = "flannel"
+
+	// DefaultPodCIDR is the default pod CIDR block.
+	DefaultPodCIDR = "10.244.0.0/16"
+
+	// DefaultServiceCIDR is the default service CIDR block.
+	DefaultServiceCIDR = "10.96.0.0/12"
 )
 
 // See https://linux.die.net/man/3/klogctl

pkg/net/net.go

@@ -6,6 +6,8 @@ package net
 
 import (
 	"net"
+
+	"github.com/pkg/errors"
 )
 
 // IPAddrs finds and returns a list of non-loopback IPv4 addresses of the
@@ -40,3 +42,24 @@ func FormatAddress(addr string) string {
 	}
 	return addr
 }
+
+// NthIPInNetwork takes an IPNet and returns the nth IP in it.
+func NthIPInNetwork(network *net.IPNet, n int) (net.IP, error) {
+	ip := network.IP
+	dst := make([]byte, len(ip))
+	copy(dst, ip)
+	for i := 0; i < n; i++ {
+		for j := len(dst) - 1; j >= 0; j-- {
+			dst[j]++
+			if dst[j] > 0 {
+				break
+			}
+		}
+	}
+
+	if network.Contains(dst) {
+		return dst, nil
+	}
+
+	return nil, errors.New("network does not contain enough IPs")
+}

pkg/net/net_test.go

@@ -5,6 +5,8 @@
 package net
 
 import (
+	"net"
+	"reflect"
 	"testing"
 
 	"gotest.tools/assert"
@@ -23,3 +25,73 @@ func TestFormatAddress(t *testing.T) {
 	assert.Equal(t, FormatAddress("192.168.1.1"), "192.168.1.1")
 	assert.Equal(t, FormatAddress("alpha.beta.gamma.com"), "alpha.beta.gamma.com")
 }
+
+// nolint: scopelint
+func TestNthIPInNetwork(t *testing.T) {
+	type args struct {
+		network *net.IPNet
+		n       int
+	}
+	tests := []struct {
+		name string
+		args args
+		want net.IP
+	}{
+		{
+			name: "increment IPv4 by 1",
+			args: args{
+				network: &net.IPNet{
+					IP:   net.IP{10, 96, 0, 0},
+					Mask: net.IPMask{255, 255, 255, 0},
+				},
+				n: 1,
+			},
+			want: net.IP{10, 96, 0, 1},
+		},
+		{
+			name: "increment IPv4 by 10",
+			args: args{
+				network: &net.IPNet{
+					IP:   net.IP{10, 96, 0, 0},
+					Mask: net.IPMask{255, 255, 255, 0},
+				},
+				n: 10,
+			},
+			want: net.IP{10, 96, 0, 10},
+		},
+		{
+			name: "increment IPv6 by 1",
+			args: args{
+				network: &net.IPNet{
+					IP:   net.ParseIP("2001:db8:a0b:12f0::1"),
+					Mask: net.IPMask{255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+				},
+				n: 1,
+			},
+			want: net.ParseIP("2001:db8:a0b:12f0::2"),
+		},
+		{
+			name: "increment IPv6 by 10",
+			args: args{
+				network: &net.IPNet{
+					IP:   net.ParseIP("2001:db8:a0b:12f0::1"),
+					Mask: net.IPMask{255, 255, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
+				},
+				n: 10,
+			},
+			want: net.ParseIP("2001:db8:a0b:12f0::b"),
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := NthIPInNetwork(tt.args.network, tt.args.n)
+			if err != nil {
+				t.Errorf("%v", err)
+			}
+
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("NthFromIP() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}