Add EUI on IPv6 L2VNIs for IPv6 ND

telekom · Nov 15, 2024 · bb2d255 · bb2d255
1 parent c334ded
commit bb2d255
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Showing 3 changed files with 46 additions and 17 deletions.
diff --git a/pkg/nl/create.go b/pkg/nl/create.go
@@ -26,7 +26,7 @@ func (n *Manager) createVRF(vrfName string, table int) (*netlink.Vrf, error) {
 	if err := n.toolkit.LinkAdd(&netlinkVrf); err != nil {
 		return nil, fmt.Errorf("error adding link: %w", err)
 	}
-	if err := n.disableEUIAutogeneration(vrfName); err != nil {
+	if err := n.setEUIAutogeneration(vrfName, false); err != nil {
 		return nil, err
 	}
 	if err := n.toolkit.LinkSetUp(&netlinkVrf); err != nil {
@@ -36,7 +36,7 @@ func (n *Manager) createVRF(vrfName string, table int) (*netlink.Vrf, error) {
 	return &netlinkVrf, nil
 }
 
-func (n *Manager) createBridge(bridgeName string, macAddress *net.HardwareAddr, masterIdx, mtu int, underlayRMAC bool) (*netlink.Bridge, error) {
+func (n *Manager) createBridge(bridgeName string, macAddress *net.HardwareAddr, masterIdx, mtu int, underlayRMAC, assignEUI bool) (*netlink.Bridge, error) {
 	netlinkBridge := netlink.Bridge{
 		LinkAttrs: netlink.LinkAttrs{
 			Name: bridgeName,
@@ -64,7 +64,7 @@ func (n *Manager) createBridge(bridgeName string, macAddress *net.HardwareAddr,
 	if err := n.toolkit.LinkAdd(&netlinkBridge); err != nil {
 		return nil, fmt.Errorf("error adding link: %w", err)
 	}
-	if err := n.disableEUIAutogeneration(bridgeName); err != nil {
+	if err := n.setEUIAutogeneration(bridgeName, assignEUI); err != nil {
 		return nil, fmt.Errorf("error disabling EUI autogeneration: %w", err)
 	}
 
@@ -109,21 +109,25 @@ func (n *Manager) createVXLAN(vxlanName string, bridgeIdx, vni, mtu int, hairpin
 			return nil, fmt.Errorf("error setting link's hairpin mode: %w", err)
 		}
 	}
-	if err := n.disableEUIAutogeneration(vxlanName); err != nil {
+	if err := n.setEUIAutogeneration(vxlanName, false); err != nil {
 		return nil, err
 	}
 
 	return &netlinkVXLAN, nil
 }
 
-func (*Manager) disableEUIAutogeneration(intfName string) error {
+func (*Manager) setEUIAutogeneration(intfName string, generateEUI bool) error {
 	fileName := fmt.Sprintf("%s/ipv6/conf/%s/addr_gen_mode", procSysNetPath, intfName)
 	file, err := os.OpenFile(fileName, os.O_WRONLY, 0)
 	if err != nil {
 		return fmt.Errorf("error opening file: %w", err)
 	}
 	defer file.Close()
-	if _, err := file.WriteString("1\n"); err != nil {
+	value := "1"
+	if generateEUI {
+		value = "0"
+	}
+	if _, err := fmt.Fprintf(file, "%s\n", value); err != nil {
 		return fmt.Errorf("error writing to file: %w", err)
 	}
 	return nil
@@ -142,13 +146,11 @@ func (n *Manager) createLink(vethName, peerName string, masterIdx, mtu int, gene
 		return nil, fmt.Errorf("error adding link: %w", err)
 	}
 
-	if !generateEUI {
-		if err := n.disableEUIAutogeneration(vethName); err != nil {
-			return nil, err
-		}
-		if err := n.disableEUIAutogeneration(peerName); err != nil {
-			return nil, err
-		}
+	if err := n.setEUIAutogeneration(vethName, generateEUI); err != nil {
+		return nil, err
+	}
+	if err := n.setEUIAutogeneration(peerName, generateEUI); err != nil {
+		return nil, err
 	}
 
 	return &netlinkVeth, nil

diff --git a/pkg/nl/layer2.go b/pkg/nl/layer2.go
@@ -130,7 +130,7 @@ func (n *Manager) CreateL2(info *Layer2Information) error {
 }
 
 func (n *Manager) setupBridge(info *Layer2Information, masterIdx int) (*netlink.Bridge, error) {
-	bridge, err := n.createBridge(fmt.Sprintf("%s%d", layer2Prefix, info.VlanID), info.AnycastMAC, masterIdx, info.MTU, false)
+	bridge, err := n.createBridge(fmt.Sprintf("%s%d", layer2Prefix, info.VlanID), info.AnycastMAC, masterIdx, info.MTU, false, len(info.AnycastGateways) > 0)
 	if err != nil {
 		return nil, err
 	}
@@ -247,7 +247,29 @@ func (n *Manager) reconcileIPAddresses(intf netlink.Link, current, desired []*ne
 	return nil
 }
 
+func (n *Manager) reconcileEUIAutogeneration(intfName string, intf netlink.Link, desired []*netlink.Addr) error {
+	enableEUI := len(desired) > 0
+	if err := n.setEUIAutogeneration(intfName, enableEUI); err != nil {
+		return fmt.Errorf("error setting EUI autogeneration: %w", err)
+	}
+	if !enableEUI {
+		addresses, err := n.toolkit.AddrList(intf, unix.AF_INET6)
+		if err != nil {
+			return fmt.Errorf("error listing link's IPv6 addresses: %w", err)
+		}
+		for i := range addresses {
+			if addresses[i].IP.IsLinkLocalUnicast() {
+				if err := n.toolkit.AddrDel(intf, &addresses[i]); err != nil {
+					return fmt.Errorf("error removing link local IPv6 address: %w", err)
+				}
+			}
+		}
+	}
+	return nil
+}
+
 func (n *Manager) ReconcileL2(current, desired *Layer2Information) error {
+	bridgeName := fmt.Sprintf("%s%d", layer2Prefix, current.VlanID)
 	if len(desired.AnycastGateways) > 0 && desired.AnycastMAC == nil {
 		return fmt.Errorf("anycastGateways require anycastMAC to be set")
 	}
@@ -282,7 +304,7 @@ func (n *Manager) ReconcileL2(current, desired *Layer2Information) error {
 		return err
 	}
 
-	if err := n.configureBridge(fmt.Sprintf("%s%d", layer2Prefix, current.VlanID)); err != nil {
+	if err := n.configureBridge(bridgeName); err != nil {
 		return err
 	}
 
@@ -291,7 +313,12 @@ func (n *Manager) ReconcileL2(current, desired *Layer2Information) error {
 	}
 
 	// Add/Remove anycast gateways
-	return n.reconcileIPAddresses(current.bridge, current.AnycastGateways, desired.AnycastGateways)
+	if err := n.reconcileIPAddresses(current.bridge, current.AnycastGateways, desired.AnycastGateways); err != nil {
+		return err
+	}
+
+	// Reconcile EUI Autogeneration
+	return n.reconcileEUIAutogeneration(bridgeName, current.bridge, desired.AnycastGateways)
 }
 
 func (n *Manager) setMTU(current, desired *Layer2Information) error {

diff --git a/pkg/nl/layer3.go b/pkg/nl/layer3.go
@@ -39,7 +39,7 @@ func (n *Manager) CreateL3(info VRFInformation) error {
 		return err
 	}
 
-	bridge, err := n.createBridge(bridgePrefix+info.Name, nil, vrf.Attrs().Index, defaultMtu, true)
+	bridge, err := n.createBridge(bridgePrefix+info.Name, nil, vrf.Attrs().Index, defaultMtu, true, false)
 	if err != nil {
 		return err
 	}