initial implementation of ipv6 ipam

Author: Rahul Sharma

cloud/linode/nodeipamcontroller.go

@@ -28,20 +28,21 @@ import (
 	v1 "k8s.io/client-go/informers/core/v1"
 	"k8s.io/client-go/kubernetes"
 	cloudprovider "k8s.io/cloud-provider"
-	nodeipamcontroller "k8s.io/kubernetes/pkg/controller/nodeipam"
-	"k8s.io/kubernetes/pkg/controller/nodeipam/ipam"
 	netutils "k8s.io/utils/net"
+
+	nodeipamcontroller "github.com/linode/linode-cloud-controller-manager/cloud/nodeipam"
+	"github.com/linode/linode-cloud-controller-manager/cloud/nodeipam/ipam"
 )
 
 const (
-	maxAllowedNodeCIDRs = 2
+	maxAllowedNodeCIDRsIPv4 = 1
 )
 
 var (
 	// defaultNodeMaskCIDRIPv4 is default mask size for IPv4 node cidr
 	defaultNodeMaskCIDRIPv4 = 24
 	// defaultNodeMaskCIDRIPv6 is default mask size for IPv6 node cidr
-	defaultNodeMaskCIDRIPv6 = 64
+	defaultNodeMaskCIDRIPv6 = 112
 )
 
 func startNodeIpamController(stopCh <-chan struct{}, cloud cloudprovider.Interface, nodeInformer v1.NodeInformer, kubeclient kubernetes.Interface) error {
@@ -54,19 +55,13 @@ func startNodeIpamController(stopCh <-chan struct{}, cloud cloudprovider.Interfa
 	}
 
 	// failure: bad cidrs in config
-	clusterCIDRs, dualStack, err := processCIDRs(Options.ClusterCIDRIPv4)
+	clusterCIDRs, err := processCIDRs(Options.ClusterCIDRIPv4)
 	if err != nil {
 		return fmt.Errorf("processCIDRs failed: %w", err)
 	}
 
-	// failure: more than one cidr but they are not configured as dual stack
-	if len(clusterCIDRs) > 1 && !dualStack {
-		return fmt.Errorf("len of ClusterCIDRs==%v and they are not configured as dual stack (at least one from each IPFamily", len(clusterCIDRs))
-	}
-
-	// failure: more than cidrs is not allowed even with dual stack
-	if len(clusterCIDRs) > maxAllowedNodeCIDRs {
-		return fmt.Errorf("len of clusters is:%v > more than max allowed of %d", len(clusterCIDRs), maxAllowedNodeCIDRs)
+	if len(clusterCIDRs) > maxAllowedNodeCIDRsIPv4 {
+		return fmt.Errorf("too many clusterCIDRs specified for ipv4, max allowed is %d", maxAllowedNodeCIDRsIPv4)
 	}
 
 	/* TODO: uncomment and fix if we want to support service cidr overlap with nodecidr
@@ -98,7 +93,7 @@ func startNodeIpamController(stopCh <-chan struct{}, cloud cloudprovider.Interfa
 	}
 	*/
 
-	nodeCIDRMaskSizes := setNodeCIDRMaskSizes(clusterCIDRs)
+	nodeCIDRMaskSizes := setNodeCIDRMaskSizes()
 
 	ctx := wait.ContextForChannel(stopCh)
 
@@ -111,7 +106,7 @@ func startNodeIpamController(stopCh <-chan struct{}, cloud cloudprovider.Interfa
 		serviceCIDR,
 		secondaryServiceCIDR,
 		nodeCIDRMaskSizes,
-		ipam.RangeAllocatorType,
+		ipam.CloudAllocatorType,
 	)
 	if err != nil {
 		return err
@@ -121,47 +116,25 @@ func startNodeIpamController(stopCh <-chan struct{}, cloud cloudprovider.Interfa
 	return nil
 }
 
-// processCIDRs is a helper function that works on a comma separated cidrs and returns
-// a list of typed cidrs
-// a flag if cidrs represents a dual stack
-// error if failed to parse any of the cidrs
-func processCIDRs(cidrsList string) ([]*net.IPNet, bool, error) {
+// processCIDR is a helper function that works on cidr and returns a list of typed cidrs
+// error if failed to parse the cidr
+func processCIDRs(cidrsList string) ([]*net.IPNet, error) {
 	cidrsSplit := strings.Split(strings.TrimSpace(cidrsList), ",")
 
 	cidrs, err := netutils.ParseCIDRs(cidrsSplit)
 	if err != nil {
-		return nil, false, err
-	}
-
-	// if cidrs has an error then the previous call will fail
-	// safe to ignore error checking on next call
-	dualstack, err := netutils.IsDualStackCIDRs(cidrs)
-	if err != nil {
-		return nil, false, fmt.Errorf("failed to perform dualstack check on cidrs: %w", err)
+		return nil, err
 	}
 
-	return cidrs, dualstack, nil
+	return cidrs, nil
 }
 
-func setNodeCIDRMaskSizes(clusterCIDRs []*net.IPNet) []int {
-	sortedSizes := func(maskSizeIPv4, maskSizeIPv6 int) []int {
-		nodeMaskCIDRs := make([]int, len(clusterCIDRs))
-
-		for idx, clusterCIDR := range clusterCIDRs {
-			if netutils.IsIPv6CIDR(clusterCIDR) {
-				nodeMaskCIDRs[idx] = maskSizeIPv6
-			} else {
-				nodeMaskCIDRs[idx] = maskSizeIPv4
-			}
-		}
-		return nodeMaskCIDRs
-	}
-
+func setNodeCIDRMaskSizes() []int {
 	if Options.NodeCIDRMaskSizeIPv4 != 0 {
 		defaultNodeMaskCIDRIPv4 = Options.NodeCIDRMaskSizeIPv4
 	}
 	if Options.NodeCIDRMaskSizeIPv6 != 0 {
 		defaultNodeMaskCIDRIPv6 = Options.NodeCIDRMaskSizeIPv6
 	}
-	return sortedSizes(defaultNodeMaskCIDRIPv4, defaultNodeMaskCIDRIPv6)
+	return []int{defaultNodeMaskCIDRIPv4, defaultNodeMaskCIDRIPv6}
 }

cloud/linode/nodeipamcontroller_test.go

@@ -33,65 +33,22 @@ import (
 
 func Test_setNodeCIDRMaskSizes(t *testing.T) {
 	type args struct {
-		clusterCIDRs []*net.IPNet
-		ipv4NetMask  int
-		ipv6NetMask  int
+		ipv4NetMask int
+		ipv6NetMask int
 	}
-	_, ipv4Net, _ := net.ParseCIDR("10.192.0.0/10")
-	_, ipv6Net, _ := net.ParseCIDR("fd00::/56")
 	tests := []struct {
 		name string
 		args args
 		want []int
 	}{
 		{
-			name: "empty cluster cidrs",
-			args: args{
-				clusterCIDRs: []*net.IPNet{},
-			},
-			want: []int{},
-		},
-		{
-			name: "single cidr",
-			args: args{
-				clusterCIDRs: []*net.IPNet{
-					{
-						IP:   ipv4Net.IP,
-						Mask: ipv4Net.Mask,
-					},
-				},
-			},
-			want: []int{defaultNodeMaskCIDRIPv4},
-		},
-		{
-			name: "two cidrs",
-			args: args{
-				clusterCIDRs: []*net.IPNet{
-					{
-						IP:   ipv4Net.IP,
-						Mask: ipv4Net.Mask,
-					},
-					{
-						IP:   ipv6Net.IP,
-						Mask: ipv6Net.Mask,
-					},
-				},
-			},
+			name: "default cidr mask sizes",
+			args: args{},
 			want: []int{defaultNodeMaskCIDRIPv4, defaultNodeMaskCIDRIPv6},
 		},
 		{
 			name: "two cidrs with custom mask sizes",
 			args: args{
-				clusterCIDRs: []*net.IPNet{
-					{
-						IP:   ipv4Net.IP,
-						Mask: ipv4Net.Mask,
-					},
-					{
-						IP:   ipv6Net.IP,
-						Mask: ipv6Net.Mask,
-					},
-				},
 				ipv4NetMask: 25,
 				ipv6NetMask: 80,
 			},
@@ -112,7 +69,7 @@ func Test_setNodeCIDRMaskSizes(t *testing.T) {
 			if tt.args.ipv6NetMask != 0 {
 				Options.NodeCIDRMaskSizeIPv6 = tt.args.ipv6NetMask
 			}
-			got := setNodeCIDRMaskSizes(tt.args.clusterCIDRs)
+			got := setNodeCIDRMaskSizes()
 			if !reflect.DeepEqual(got, tt.want) {
 				t.Errorf("setNodeCIDRMaskSizes() = %v, want %v", got, tt.want)
 			}
@@ -125,22 +82,19 @@ func Test_processCIDRs(t *testing.T) {
 		cidrsList string
 	}
 	_, ipv4Net, _ := net.ParseCIDR("10.192.0.0/10")
-	_, ipv6Net, _ := net.ParseCIDR("fd00::/56")
 	tests := []struct {
-		name        string
-		args        args
-		want        []*net.IPNet
-		ipv6Enabled bool
-		wantErr     bool
+		name    string
+		args    args
+		want    []*net.IPNet
+		wantErr bool
 	}{
 		{
 			name: "empty cidr list",
 			args: args{
 				cidrsList: "",
 			},
-			want:        nil,
-			ipv6Enabled: false,
-			wantErr:     true,
+			want:    nil,
+			wantErr: true,
 		},
 		{
 			name: "valid ipv4 cidr",
@@ -153,41 +107,19 @@ func Test_processCIDRs(t *testing.T) {
 					Mask: ipv4Net.Mask,
 				},
 			},
-			ipv6Enabled: false,
-			wantErr:     false,
-		},
-		{
-			name: "valid ipv4 and ipv6 cidrs",
-			args: args{
-				cidrsList: "10.192.0.0/10,fd00::/56",
-			},
-			want: []*net.IPNet{
-				{
-					IP:   ipv4Net.IP,
-					Mask: ipv4Net.Mask,
-				},
-				{
-					IP:   ipv6Net.IP,
-					Mask: ipv6Net.Mask,
-				},
-			},
-			ipv6Enabled: true,
-			wantErr:     false,
+			wantErr: false,
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			got, got1, err := processCIDRs(tt.args.cidrsList)
+			got, err := processCIDRs(tt.args.cidrsList)
 			if (err != nil) != tt.wantErr {
 				t.Errorf("processCIDRs() error = %v, wantErr %v", err, tt.wantErr)
 				return
 			}
 			if !reflect.DeepEqual(got, tt.want) {
 				t.Errorf("processCIDRs() got = %v, want %v", got, tt.want)
 			}
-			if got1 != tt.ipv6Enabled {
-				t.Errorf("processCIDRs() got1 = %v, want %v", got1, tt.ipv6Enabled)
-			}
 		})
 	}
 }
@@ -232,26 +164,14 @@ func Test_startNodeIpamController(t *testing.T) {
 			wantErr: true,
 		},
 		{
-			name: "more than one ipv4 cidrs specified",
-			args: args{
-				stopCh:            make(<-chan struct{}),
-				cloud:             nil,
-				nodeInformer:      nil,
-				kubeclient:        nil,
-				allocateNodeCIDRs: true,
-				clusterCIDR:       "10.192.0.0/10,192.168.0.0/16",
-			},
-			wantErr: true,
-		},
-		{
-			name: "more than two cidrs specified",
+			name: "more than one cidr specified",
 			args: args{
 				stopCh:            make(<-chan struct{}),
 				cloud:             nil,
 				nodeInformer:      nil,
 				kubeclient:        nil,
 				allocateNodeCIDRs: true,
-				clusterCIDR:       "10.192.0.0/10,fd00::/80,192.168.0.0/16",
+				clusterCIDR:       "10.192.0.0/10,fd00::/80",
 			},
 			wantErr: true,
 		},

cloud/nodeipam/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package nodeipam contains code for syncing cloud instances with
+// node registry
+package nodeipam