Merge pull request #1919 from thomasferrandiz/rebased-remove-multiclu…

…stercidr

Remove multiclustercidr code

Documentation/kube-flannel.yml

@@ -34,13 +34,6 @@ rules:
   - nodes/status
   verbs:
   - patch
-- apiGroups:
-  - networking.k8s.io
-  resources:
-  - clustercidrs
-  verbs:
-  - list
-  - watch
 ---
 kind: ClusterRoleBinding
 apiVersion: rbac.authorization.k8s.io/v1

go.mod

@@ -128,7 +128,7 @@ require (
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
 	k8s.io/kube-openapi v0.0.0-20221012153701-172d655c2280 // indirect
-	k8s.io/utils v0.0.0-20230220204549-a5ecb0141aa5
+	k8s.io/utils v0.0.0-20221107191617-1a15be271d1d // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.2.3 // indirect
 	sigs.k8s.io/yaml v1.3.0 // indirect
 )

go.sum

@@ -776,8 +776,8 @@ k8s.io/klog/v2 v2.120.1 h1:QXU6cPEOIslTGvZaXvFWiP9VKyeet3sawzTOvdXb4Vw=
 k8s.io/klog/v2 v2.120.1/go.mod h1:3Jpz1GvMt720eyJH1ckRHK1EDfpxISzJ7I9OYgaDtPE=
 k8s.io/kube-openapi v0.0.0-20221012153701-172d655c2280 h1:+70TFaan3hfJzs+7VK2o+OGxg8HsuBr/5f6tVAjDu6E=
 k8s.io/kube-openapi v0.0.0-20221012153701-172d655c2280/go.mod h1:+Axhij7bCpeqhklhUTe3xmOn6bWxolyZEeyaFpjGtl4=
-k8s.io/utils v0.0.0-20230220204549-a5ecb0141aa5 h1:kmDqav+P+/5e1i9tFfHq1qcF3sOrDp+YEkVDAHu7Jwk=
-k8s.io/utils v0.0.0-20230220204549-a5ecb0141aa5/go.mod h1:OLgZIPagt7ERELqWJFomSt595RzquPNLL48iOWgYOg0=
+k8s.io/utils v0.0.0-20221107191617-1a15be271d1d h1:0Smp/HP1OH4Rvhe+4B8nWGERtlqAGSftbSbbmm45oFs=
+k8s.io/utils v0.0.0-20221107191617-1a15be271d1d/go.mod h1:OLgZIPagt7ERELqWJFomSt595RzquPNLL48iOWgYOg0=
 rsc.io/binaryregexp v0.2.0/go.mod h1:qTv7/COck+e2FymRvadv62gMdZztPaShugOCi3I+8D8=
 rsc.io/quote/v3 v3.1.0/go.mod h1:yEA65RcK8LyAZtP9Kv3t0HmxON59tX3rD+tICJqUlj0=
 rsc.io/sampler v1.3.0/go.mod h1:T1hPZKmBbMNahiBKFy5HrXp6adAjACjK9JXDnKaTXpA=

main.go

@@ -346,39 +346,19 @@ func main() {
 		os.Exit(1)
 	}
 
-	flannelIPv4Net := ip.IP4Net{}
-	flannelIpv6Net := ip.IP6Net{}
-	if config.EnableIPv4 {
-		flannelIPv4Net, err = config.GetFlannelNetwork(&bn.Lease().Subnet)
-		if err != nil {
-			log.Error(err)
-			cancel()
-			wg.Wait()
-			os.Exit(1)
-		}
-	}
-	if config.EnableIPv6 {
-		flannelIpv6Net, err = config.GetFlannelIPv6Network(&bn.Lease().IPv6Subnet)
-		if err != nil {
-			log.Error(err)
-			cancel()
-			wg.Wait()
-			os.Exit(1)
-		}
-	}
 	// Set up ipMasq if needed
 	if opts.ipMasq {
-		prevNetworks := ReadCIDRsFromSubnetFile(opts.subnetFile, "FLANNEL_NETWORK")
+		prevNetwork := ReadCIDRFromSubnetFile(opts.subnetFile, "FLANNEL_NETWORK")
 		prevSubnet := ReadCIDRFromSubnetFile(opts.subnetFile, "FLANNEL_SUBNET")
 
-		prevIPv6Networks := ReadIP6CIDRsFromSubnetFile(opts.subnetFile, "FLANNEL_IPV6_NETWORK")
+		prevIPv6Network := ReadIP6CIDRFromSubnetFile(opts.subnetFile, "FLANNEL_IPV6_NETWORK")
 		prevIPv6Subnet := ReadIP6CIDRFromSubnetFile(opts.subnetFile, "FLANNEL_IPV6_SUBNET")
 
 		err = trafficMngr.SetupAndEnsureMasqRules(ctx,
-			flannelIPv4Net, prevSubnet,
-			prevNetworks,
-			flannelIpv6Net, prevIPv6Subnet,
-			prevIPv6Networks,
+			config.Network, prevSubnet,
+			prevNetwork,
+			config.IPv6Network, prevIPv6Subnet,
+			prevIPv6Network,
 			bn.Lease(),
 			opts.iptablesResyncSeconds)
 		if err != nil {
@@ -394,8 +374,8 @@ func main() {
 	// In Docker 1.13 and later, Docker sets the default policy of the FORWARD chain to DROP.
 	if opts.iptablesForwardRules {
 		trafficMngr.SetupAndEnsureForwardRules(ctx,
-			flannelIPv4Net,
-			flannelIpv6Net,
+			config.Network,
+			config.IPv6Network,
 			opts.iptablesResyncSeconds)
 	}
 

pkg/backend/ipip/ipip.go

@@ -90,12 +90,7 @@ func (be *IPIPBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGroup,
 		return nil, fmt.Errorf("failed to acquire lease: %v", err)
 	}
 
-	net, err := config.GetFlannelNetwork(&n.SubnetLease.Subnet)
-	if err != nil {
-		return nil, err
-	}
-
-	link, err := be.configureIPIPDevice(n.SubnetLease, net)
+	link, err := be.configureIPIPDevice(n.SubnetLease, config.Network)
 
 	if err != nil {
 		return nil, err

pkg/backend/udp/udp_amd64.go

@@ -79,15 +79,11 @@ func (be *UdpBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGroup, c
 		return nil, fmt.Errorf("failed to acquire lease: %v", err)
 	}
 
-	net, err := config.GetFlannelNetwork(&l.Subnet)
-	if err != nil {
-		return nil, err
-	}
 	// Tunnel's subnet is that of the whole overlay network (e.g. /16)
 	// and not that of the individual host (e.g. /24)
 	tunNet := ip.IP4Net{
 		IP:        l.Subnet.IP,
-		PrefixLen: net.PrefixLen,
+		PrefixLen: config.Network.PrefixLen,
 	}
 
 	return newNetwork(be.sm, be.extIface, cfg.Port, tunNet, l)

pkg/backend/vxlan/vxlan.go

@@ -211,20 +211,12 @@ func (be *VXLANBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGroup,
 	// This IP is just used as a source address for host to workload traffic (so
 	// the return path for the traffic has an address on the flannel network to use as the destination)
 	if config.EnableIPv4 {
-		net, err := config.GetFlannelNetwork(&lease.Subnet)
-		if err != nil {
-			return nil, err
-		}
-		if err := dev.Configure(ip.IP4Net{IP: lease.Subnet.IP, PrefixLen: 32}, net); err != nil {
+		if err := dev.Configure(ip.IP4Net{IP: lease.Subnet.IP, PrefixLen: 32}, config.Network); err != nil {
 			return nil, fmt.Errorf("failed to configure interface %s: %w", dev.link.Attrs().Name, err)
 		}
 	}
 	if config.EnableIPv6 {
-		net, err := config.GetFlannelIPv6Network(&lease.IPv6Subnet)
-		if err != nil {
-			return nil, err
-		}
-		if err := v6Dev.ConfigureIPv6(ip.IP6Net{IP: lease.IPv6Subnet.IP, PrefixLen: 128}, net); err != nil {
+		if err := v6Dev.ConfigureIPv6(ip.IP6Net{IP: lease.IPv6Subnet.IP, PrefixLen: 128}, config.IPv6Network); err != nil {
 			return nil, fmt.Errorf("failed to configure interface %s: %w", v6Dev.link.Attrs().Name, err)
 		}
 	}

pkg/backend/wireguard/wireguard.go

@@ -171,25 +171,17 @@ func (be *WireguardBackend) RegisterNetwork(ctx context.Context, wg *sync.WaitGr
 	}
 
 	if config.EnableIPv4 {
-		net, err := config.GetFlannelNetwork(&lease.Subnet)
-		if err != nil {
-			return nil, err
-		}
-		err = dev.Configure(lease.Subnet.IP, net)
+		err = dev.Configure(lease.Subnet.IP, config.Network)
 		if err != nil {
 			return nil, err
 		}
 	}
 
 	if config.EnableIPv6 {
-		ipv6net, err := config.GetFlannelIPv6Network(&lease.IPv6Subnet)
-		if err != nil {
-			return nil, err
-		}
 		if cfg.Mode == Separate {
-			err = v6Dev.ConfigureV6(lease.IPv6Subnet.IP, ipv6net)
+			err = v6Dev.ConfigureV6(lease.IPv6Subnet.IP, config.IPv6Network)
 		} else {
-			err = dev.ConfigureV6(lease.IPv6Subnet.IP, ipv6net)
+			err = dev.ConfigureV6(lease.IPv6Subnet.IP, config.IPv6Network)
 		}
 		if err != nil {
 			return nil, err

pkg/backend/wireguard/wireguard_network.go

@@ -183,13 +183,9 @@ func (n *network) handleSubnetEvents(ctx context.Context, batch []lease.Event) {
 					if err != nil {
 						log.Errorf("could not read network config: %v", err)
 					}
-					flannelnet, err := netconf.GetFlannelNetwork(&event.Lease.Subnet)
-					if err != nil {
-						log.Errorf("could not get flannel network: %v", err)
-					}
 
-					if err := n.dev.addRoute(flannelnet.ToIPNet()); err != nil {
-						log.Errorf("failed to add ipv4 route to (%s): %v", flannelnet, err)
+					if err := n.dev.addRoute(netconf.Network.ToIPNet()); err != nil {
+						log.Errorf("failed to add ipv4 route to (%s): %v", netconf.Network, err)
 					}
 				}
 
@@ -206,13 +202,9 @@ func (n *network) handleSubnetEvents(ctx context.Context, batch []lease.Event) {
 					if err != nil {
 						log.Errorf("could not read network config: %v", err)
 					}
-					ipv6flannelnet, err := netconf.GetFlannelIPv6Network(&event.Lease.IPv6Subnet)
-					if err != nil {
-						log.Errorf("could not get flannel network: %v", err)
-					}
 
-					if err := n.v6Dev.addRoute(ipv6flannelnet.ToIPNet()); err != nil {
-						log.Errorf("failed to add ipv6 route to (%s): %v", ipv6flannelnet, err)
+					if err := n.v6Dev.addRoute(netconf.IPv6Network.ToIPNet()); err != nil {
+						log.Errorf("failed to add ipv6 route to (%s): %v", netconf.IPv6Network, err)
 					}
 				}
 			} else {
@@ -242,21 +234,13 @@ func (n *network) handleSubnetEvents(ctx context.Context, batch []lease.Event) {
 				if err != nil {
 					log.Errorf("could not read network config: %v", err)
 				}
-				flannelnet, err := netconf.GetFlannelNetwork(&event.Lease.Subnet)
-				if err != nil {
-					log.Errorf("could not get flannel network: %v", err)
-				}
 
-				if err := n.dev.addRoute(flannelnet.ToIPNet()); err != nil {
-					log.Errorf("failed to add ipv4 route to (%s): %v", flannelnet, err)
-				}
-				ipv6flannelnet, err := netconf.GetFlannelIPv6Network(&event.Lease.IPv6Subnet)
-				if err != nil {
-					log.Errorf("could not get flannel network: %v", err)
+				if err := n.dev.addRoute(netconf.Network.ToIPNet()); err != nil {
+					log.Errorf("failed to add ipv4 route to (%s): %v", netconf.Network, err)
 				}
 
-				if err := n.dev.addRoute(ipv6flannelnet.ToIPNet()); err != nil {
-					log.Errorf("failed to add ipv6 route to (%s): %v", ipv6flannelnet, err)
+				if err := n.dev.addRoute(netconf.IPv6Network.ToIPNet()); err != nil {
+					log.Errorf("failed to add ipv6 route to (%s): %v", netconf.IPv6Network, err)
 				}
 			}
 

pkg/subnet/config.go

@@ -19,11 +19,8 @@ import (
 	"errors"
 	"fmt"
 	"math/big"
-	"net"
 
 	"github.com/flannel-io/flannel/pkg/ip"
-	"k8s.io/klog/v2"
-	netutils "k8s.io/utils/net"
 )
 
 type Config struct {
@@ -32,8 +29,6 @@ type Config struct {
 	EnableNFTables bool
 	Network        ip.IP4Net
 	IPv6Network    ip.IP6Net
-	Networks       []ip.IP4Net
-	IPv6Networks   []ip.IP6Net
 	SubnetMin      ip.IP4
 	SubnetMax      ip.IP4
 	IPv6SubnetMin  *ip.IP6
@@ -73,9 +68,6 @@ func ParseConfig(s string) (*Config, error) {
 	}
 	cfg.BackendType = bt
 
-	cfg.Networks = make([]ip.IP4Net, 0)
-	cfg.IPv6Networks = make([]ip.IP6Net, 0)
-
 	return cfg, nil
 }
 
@@ -204,119 +196,3 @@ func CheckNetworkConfig(config *Config) error {
 	}
 	return nil
 }
-
-// GetFlannelNetwork returns the relevant IPv4 network (i.e. clusterCIDR) for subnet sn
-// If Networks is not empty, GetFlannelNetwork returns the first networks that contains subnet sn.
-// If Networks is empty, this means we are not using the MultiClusterCIDR API
-// so GetFlannelNetwork falls back to the standard behavior and returns the single Network entry
-func (c *Config) GetFlannelNetwork(sn *ip.IP4Net) (ip.IP4Net, error) {
-	if c.HasNetworks() {
-		for _, net := range c.Networks {
-			if net.ContainsCIDR(sn) {
-				return net, nil
-			}
-		}
-		return ip.IP4Net{}, fmt.Errorf("could not find flannel networks matching subnet %s", sn)
-	} else {
-		emptyNet := ip.IP4Net{}
-		if c.Network != emptyNet {
-			return c.Network, nil
-		} else {
-			return emptyNet, fmt.Errorf("could not find an ipv4 network in the flannel configuration")
-		}
-	}
-}
-
-// GetFlannelIPv6Network returns the relevant IPv6 network (i.e. clusterCIDR) for subnet sn
-// If Networks is not empty, GetFlannelIPv6Network returns the first networks that contains subnet sn.
-// If Networks is empty, this means we are not using the MultiClusterCIDR API
-// so GetFlannelIPv6Network falls back to the standard behavior and returns the single IPv6Network entry
-func (c *Config) GetFlannelIPv6Network(sn *ip.IP6Net) (ip.IP6Net, error) {
-	if c.HasIPv6Networks() {
-		for _, net := range c.IPv6Networks {
-			if net.ContainsCIDR(sn) {
-				return net, nil
-			}
-		}
-		return ip.IP6Net{}, fmt.Errorf("could not find flannel ipv6 networks matching subnet %s", sn)
-	} else {
-		emptyNet := ip.IP6Net{}
-		if c.IPv6Network != emptyNet {
-			return c.IPv6Network, nil
-		} else {
-			return emptyNet, fmt.Errorf("could not find an ipv6 network in the flannel configuration")
-		}
-
-	}
-}
-
-// AddNetwork adds net to either c.Networks or c.IPv6Networks depending on its type
-func (c *Config) AddNetwork(net *net.IPNet) {
-	if netutils.IsIPv4CIDR(net) {
-		ip4net := ip.FromIPNet(net)
-		if !c.containsIPv4Network(ip4net) {
-			c.Networks = append(c.Networks, ip4net)
-		}
-	} else if netutils.IsIPv6CIDR(net) {
-		ip6net := ip.FromIP6Net(net)
-		if !c.containsIPv6Network(ip6net) {
-			c.IPv6Networks = append(c.IPv6Networks, ip6net)
-		}
-	} else {
-		klog.Warningf("cannot add unknown CIDR to config: %s", net)
-	}
-}
-
-func (c *Config) containsIPv4Network(net ip.IP4Net) bool {
-	for _, ip4net := range c.Networks {
-		if net.Equal(ip4net) {
-			return true
-		}
-	}
-	return false
-}
-
-func (c *Config) containsIPv6Network(net ip.IP6Net) bool {
-	for _, ip6net := range c.IPv6Networks {
-		if net.Equal(ip6net) {
-			return true
-		}
-	}
-	return false
-}
-
-// HasNetworks returns true if there is at least 1 IPv4 network in the flannel config,
-// false otherwise
-func (c *Config) HasNetworks() bool {
-	if c.Networks != nil {
-		return len(c.Networks) > 0
-	} else {
-		return false
-	}
-}
-
-// HasIPv6Networks returns true if there is at least 1 IPv6 network in the flannel config,
-// false otherwise
-func (c *Config) HasIPv6Networks() bool {
-	if c.IPv6Networks != nil {
-		return len(c.IPv6Networks) > 0
-	} else {
-		return false
-	}
-}
-
-func (c *Config) GetNetworks() []ip.IP4Net {
-	if len(c.Networks) > 0 {
-		return c.Networks
-	} else {
-		return []ip.IP4Net{c.Network}
-	}
-}
-
-func (c *Config) GeIPv6tNetworks() []ip.IP6Net {
-	if len(c.Networks) > 0 {
-		return c.IPv6Networks
-	} else {
-		return []ip.IP6Net{c.IPv6Network}
-	}
-}