Add clustersetip module to discovery

...to allow subctl to allocate clustersetIP cidrs during join

Signed-off-by: Vishal Thapar <[email protected]>

pkg/cidr/cidr.go

@@ -272,3 +272,49 @@ func uintToIP(ip uint32) net.IP {
 
 	return netIP
 }
+
+func GetValidAllocationSize(cidrRange string, allocationSize uint) (uint, error) {
+	_, network, err := net.ParseCIDR(cidrRange)
+	if err != nil {
+		return 0, err //nolint:wrapcheck // No need to wrap here
+	}
+
+	ones, totalbits := network.Mask.Size()
+	availableSize := uint(1) << uint(totalbits-ones) //nolint:gosec // Ignore overflow conversion int -> uint
+	userClusterSize := allocationSize
+	allocationSize = nextPowerOf2(allocationSize)
+
+	if allocationSize > (availableSize / 2) {
+		return 0, fmt.Errorf("cluster size %d, should be <= %d", userClusterSize, availableSize/2)
+	}
+
+	if allocationSize == 0 {
+		return 0, errors.New("cluster size must be > 0")
+	}
+
+	return allocationSize, nil
+}
+
+// Refer: https://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
+func nextPowerOf2(n uint) uint {
+	n--
+	n |= n >> 1
+	n |= n >> 2
+	n |= n >> 4
+	n |= n >> 8
+	n |= n >> 16
+	n++
+
+	return n
+}
+
+func IsCIDRPreConfigured(clusterID string, clustersetIPNetworks map[string]*ClusterInfo) bool {
+	// ClustersetIPCIDR is not pre-configured
+	if clustersetIPNetworks[clusterID] == nil || clustersetIPNetworks[clusterID].CIDRs == nil ||
+		len(clustersetIPNetworks[clusterID].CIDRs) == 0 {
+		return false
+	}
+
+	// ClustersetIPCIDR is pre-configured
+	return true
+}

pkg/discovery/clustersetip/clustersetip.go

@@ -0,0 +1,223 @@
+/*
+SPDX-License-Identifier: Apache-2.0
+
+Copyright Contributors to the Submariner project.
+
+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 clustersetip
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+
+	"github.com/pkg/errors"
+	"github.com/submariner-io/admiral/pkg/reporter"
+	"github.com/submariner-io/submariner-operator/pkg/cidr"
+	v1 "k8s.io/api/core/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/client-go/util/retry"
+	controllerClient "sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+type Info struct {
+	Enabled bool
+	cidr.Info
+}
+
+type Config struct {
+	ClusterID        string
+	ClustersetIPCIDR string
+	AllocationSize   uint
+}
+
+func AllocateClustersetIPCIDR(clustersetIPInfo *Info) (string, error) {
+	return cidr.Allocate(&clustersetIPInfo.Info) //nolint:wrapcheck // No need to wrap
+}
+
+func ValidateClustersetIPConfiguration(clustersetIPInfo *Info, netconfig Config, status reporter.Interface) (string, error) {
+	status.Start("Validating ClustersetIP configuration")
+	defer status.End()
+
+	clustersetIPClusterSize := netconfig.AllocationSize
+	clustersetIPCIDR := netconfig.ClustersetIPCIDR
+
+	if clustersetIPClusterSize != 0 && clustersetIPClusterSize != clustersetIPInfo.AllocationSize {
+		clusterSize, err := cidr.GetValidAllocationSize(clustersetIPInfo.CIDR, clustersetIPClusterSize)
+		if err != nil {
+			return "", status.Error(err, "invalid cluster size")
+		}
+
+		clustersetIPInfo.AllocationSize = clusterSize
+	}
+
+	if clustersetIPCIDR != "" && clustersetIPClusterSize != 0 {
+		status.Failure("Only one of cluster size and clustersetip CIDR can be specified")
+
+		return "", errors.New("only one of cluster size and clustersetip CIDR can be specified")
+	}
+
+	if clustersetIPCIDR != "" {
+		err := cidr.IsValid(clustersetIPCIDR)
+		if err != nil {
+			return "", errors.Wrap(err, "specified clustersetip-cidr is invalid")
+		}
+	}
+
+	return clustersetIPCIDR, nil
+}
+
+func GetClustersetIPNetworks(ctx context.Context, client controllerClient.Client, brokerNamespace string) (*Info, *v1.ConfigMap, error) {
+	configMap, err := GetConfigMap(ctx, client, brokerNamespace)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "error retrieving clustersetip ConfigMap")
+	}
+
+	clustersetIPInfo := Info{}
+
+	err = json.Unmarshal([]byte(configMap.Data[clustersetIPEnabledKey]), &clustersetIPInfo.Enabled)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "error reading clusersetIPEnabled status")
+	}
+
+	err = json.Unmarshal([]byte(configMap.Data[clustersetIPClusterSize]), &clustersetIPInfo.AllocationSize)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "error reading ClustersetIPClusterSize")
+	}
+
+	err = json.Unmarshal([]byte(configMap.Data[clustersetIPCidrRange]), &clustersetIPInfo.CIDR)
+	if err != nil {
+		return nil, nil, errors.Wrap(err, "error reading ClustersetIPCidrRange")
+	}
+
+	clustersetIPInfo.Clusters, err = cidr.ExtractClusterInfo(configMap)
+
+	return &clustersetIPInfo, configMap, err //nolint:wrapcheck // No need to wrap
+}
+
+func assignClustersetIPs(clustersetIPInfo *Info, netconfig Config, status reporter.Interface) (string, error) {
+	status.Start("Assigning ClustersetIP IPs")
+	defer status.End()
+
+	clustersetIPCIDR := netconfig.ClustersetIPCIDR
+	clusterID := netconfig.ClusterID
+	var err error
+
+	if clustersetIPCIDR == "" {
+		// ClustersetIPCIDR not specified by the user
+		if cidr.IsCIDRPreConfigured(clusterID, clustersetIPInfo.Clusters) {
+			// clustersetipCidr already configured on this cluster
+			clustersetIPCIDR = clustersetIPInfo.Clusters[clusterID].CIDRs[0]
+			status.Success("Using pre-configured clustersetip CIDR %s", clustersetIPCIDR)
+		} else {
+			// no clustersetipCidr configured on this cluster
+			clustersetIPCIDR, err = AllocateClustersetIPCIDR(clustersetIPInfo)
+			if err != nil {
+				return "", status.Error(err, "unable to allocate clustersetip CIDR")
+			}
+
+			status.Success(fmt.Sprintf("Allocated clustersetip CIDR %s", clustersetIPCIDR))
+		}
+	} else {
+		// ClustersetIP enabled, clustersetIPCIDR specified by user
+		if cidr.IsCIDRPreConfigured(clusterID, clustersetIPInfo.Clusters) {
+			// clustersetipCidr pre-configured on this cluster
+			clustersetIPCIDR = clustersetIPInfo.Clusters[clusterID].CIDRs[0]
+			status.Warning("A pre-configured clustersetip CIDR %s was detected - not using the specified CIDR %s",
+				clustersetIPCIDR, netconfig.ClustersetIPCIDR)
+		} else {
+			// clustersetipCidr as specified by the user
+			err := cidr.CheckForOverlappingCIDRs(clustersetIPInfo.Clusters, netconfig.ClustersetIPCIDR, netconfig.ClusterID)
+			if err != nil {
+				return "", status.Error(err, "error validating overlapping clustersetip CIDRs %s", clustersetIPCIDR)
+			}
+
+			status.Success("Using specified clustersetip CIDR %s", clustersetIPCIDR)
+		}
+	}
+
+	return clustersetIPCIDR, nil
+}
+
+func ValidateExistingClustersetIPNetworks(ctx context.Context, client controllerClient.Client, namespace string) error {
+	clustersetIPInfo, _, err := GetClustersetIPNetworks(ctx, client, namespace)
+	if err != nil {
+		if apierrors.IsNotFound(err) {
+			return nil
+		}
+
+		return errors.Wrap(err, "error getting existing clustersetip configmap")
+	}
+
+	if clustersetIPInfo != nil {
+		if err = cidr.IsValid(clustersetIPInfo.CIDR); err != nil {
+			return errors.Wrap(err, "invalid ClustersetIPCidrRange")
+		}
+	}
+
+	return nil
+}
+
+func AllocateCIDRFromConfigMap(ctx context.Context, brokerAdminClient controllerClient.Client, brokerNamespace string,
+	netconfig *Config, status reporter.Interface,
+) error {
+	// Setup default clustersize if nothing specified
+	if netconfig.ClustersetIPCIDR == "" && netconfig.AllocationSize == 0 {
+		netconfig.AllocationSize = DefaultAllocationSize
+	}
+
+	retryErr := retry.RetryOnConflict(retry.DefaultRetry, func() error {
+		status.Start("Retrieving ClustersetIP information from the Broker")
+		defer status.End()
+
+		clustersetIPInfo, clustersetIPConfigMap, err := GetClustersetIPNetworks(ctx, brokerAdminClient, brokerNamespace)
+		if err != nil {
+			return status.Error(err, "unable to retrieve ClustersetIP information")
+		}
+
+		netconfig.ClustersetIPCIDR, err = ValidateClustersetIPConfiguration(clustersetIPInfo, *netconfig, status)
+		if err != nil {
+			return status.Error(err, "error validating the ClustersetIP configuration")
+		}
+
+		netconfig.ClustersetIPCIDR, err = assignClustersetIPs(clustersetIPInfo, *netconfig, status)
+		if err != nil {
+			return status.Error(err, "error assigning ClustersetIP IPs")
+		}
+
+		if clustersetIPInfo.Clusters[netconfig.ClusterID] == nil ||
+			clustersetIPInfo.Clusters[netconfig.ClusterID].CIDRs[0] != netconfig.ClustersetIPCIDR {
+			newClusterInfo := cidr.ClusterInfo{
+				ClusterID: netconfig.ClusterID,
+				CIDRs:     []string{netconfig.ClustersetIPCIDR},
+			}
+
+			status.Start("Updating the ClustersetIP information on the Broker")
+
+			err = updateConfigMap(ctx, brokerAdminClient, clustersetIPConfigMap, newClusterInfo)
+			if apierrors.IsConflict(err) {
+				status.Warning("Conflict occurred updating the ClustersetIP ConfigMap - retrying")
+			} else {
+				return status.Error(err, "error updating the ClustersetIP ConfigMap")
+			}
+
+			return err
+		}
+
+		return nil
+	})
+
+	return retryErr //nolint:wrapcheck // No need to wrap here
+}

pkg/discovery/clustersetip/clustersetip_suite_test.go

@@ -0,0 +1,30 @@
+/*
+SPDX-License-Identifier: Apache-2.0
+
+Copyright Contributors to the Submariner project.
+
+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 clustersetip_test
+
+import (
+	"testing"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+)
+
+func TestClsutersetIP(t *testing.T) {
+	RegisterFailHandler(Fail)
+	RunSpecs(t, "ClustersetIP Suite")
+}