Merge pull request #141 from squeed/missing-mac

pkg/ip: re-fetch the created link to return creation-time parameters

pkg/ip/link_linux.go

@@ -42,8 +42,14 @@ func makeVethPair(name, peer string, mtu int) (netlink.Link, error) {
 	if err := netlink.LinkAdd(veth); err != nil {
 		return nil, err
 	}
+	// Re-fetch the link to get its creation-time parameters, e.g. index and mac
+	veth2, err := netlink.LinkByName(name)
+	if err != nil {
+		netlink.LinkDel(veth) // try and clean up the link if possible.
+		return nil, err
+	}
 
-	return veth, nil
+	return veth2, nil
 }
 
 func peerExists(name string) bool {

pkg/ipam/ipam_linux.go

@@ -21,10 +21,15 @@ import (
 
 	"github.com/containernetworking/cni/pkg/types/current"
 	"github.com/containernetworking/plugins/pkg/ip"
+	"github.com/containernetworking/plugins/pkg/utils/sysctl"
 
 	"github.com/vishvananda/netlink"
 )
 
+const (
+	DisableIPv6SysctlTemplate = "net.ipv6.conf.%s.disable_ipv6"
+)
+
 // ConfigureIface takes the result of IPAM plugin and
 // applies to the ifName interface
 func ConfigureIface(ifName string, res *current.Result) error {
@@ -42,6 +47,7 @@ func ConfigureIface(ifName string, res *current.Result) error {
 	}
 
 	var v4gw, v6gw net.IP
+	var has_enabled_ipv6 bool = false
 	for _, ipc := range res.IPs {
 		if ipc.Interface == nil {
 			continue
@@ -52,6 +58,30 @@ func ConfigureIface(ifName string, res *current.Result) error {
 			return fmt.Errorf("failed to add IP addr %v to %q: invalid interface index", ipc, ifName)
 		}
 
+		// Make sure sysctl "disable_ipv6" is 0 if we are about to add
+		// an IPv6 address to the interface
+		if !has_enabled_ipv6 && ipc.Version == "6" {
+			// Enabled IPv6 for loopback "lo" and the interface
+			// being configured
+			for _, iface := range [2]string{"lo", ifName} {
+				ipv6SysctlValueName := fmt.Sprintf(DisableIPv6SysctlTemplate, iface)
+
+				// Read current sysctl value
+				value, err := sysctl.Sysctl(ipv6SysctlValueName)
+				if err != nil || value == "0" {
+					// FIXME: log warning if unable to read sysctl value
+					continue
+				}
+
+				// Write sysctl to enable IPv6
+				_, err = sysctl.Sysctl(ipv6SysctlValueName, "0")
+				if err != nil {
+					return fmt.Errorf("failed to enable IPv6 for interface %q (%s=%s): %v", iface, ipv6SysctlValueName, value, err)
+				}
+			}
+			has_enabled_ipv6 = true
+		}
+
 		addr := &netlink.Addr{IPNet: &ipc.Address, Label: ""}
 		if err = netlink.AddrAdd(link, addr); err != nil {
 			return fmt.Errorf("failed to add IP addr %v to %q: %v", ipc, ifName, err)

plugins/main/bridge/bridge_test.go

@@ -257,7 +257,14 @@ func (tester *testerV03x) cmdAddTest(tc testCase) {
 
 		Expect(len(result.Interfaces)).To(Equal(3))
 		Expect(result.Interfaces[0].Name).To(Equal(BRNAME))
+		Expect(result.Interfaces[0].Mac).To(HaveLen(17))
+
+		Expect(result.Interfaces[1].Name).To(HavePrefix("veth"))
+		Expect(result.Interfaces[1].Mac).To(HaveLen(17))
+
 		Expect(result.Interfaces[2].Name).To(Equal(IFNAME))
+		Expect(result.Interfaces[2].Mac).To(HaveLen(17)) //mac is random
+		Expect(result.Interfaces[2].Sandbox).To(Equal(tester.targetNS.Path()))
 
 		// Make sure bridge link exists
 		link, err := netlink.LinkByName(result.Interfaces[0].Name)

plugins/main/ptp/ptp_test.go

@@ -78,12 +78,14 @@ var _ = Describe("ptp Operations", func() {
 		// Make sure ptp link exists in the target namespace
 		// Then, ping the gateway
 		seenIPs := 0
+
+		wantMac := ""
 		err = targetNs.Do(func(ns.NetNS) error {
 			defer GinkgoRecover()
 
 			link, err := netlink.LinkByName(IFNAME)
 			Expect(err).NotTo(HaveOccurred())
-			Expect(link.Attrs().Name).To(Equal(IFNAME))
+			wantMac = link.Attrs().HardwareAddr.String()
 
 			for _, ipc := range res.IPs {
 				if *ipc.Interface != 1 {
@@ -105,6 +107,17 @@ var _ = Describe("ptp Operations", func() {
 
 		Expect(seenIPs).To(Equal(numIPs))
 
+		// make sure the interfaces are correct
+		Expect(res.Interfaces).To(HaveLen(2))
+
+		Expect(res.Interfaces[0].Name).To(HavePrefix("veth"))
+		Expect(res.Interfaces[0].Mac).To(HaveLen(17))
+		Expect(res.Interfaces[0].Sandbox).To(BeEmpty())
+
+		Expect(res.Interfaces[1].Name).To(Equal(IFNAME))
+		Expect(res.Interfaces[1].Mac).To(Equal(wantMac))
+		Expect(res.Interfaces[1].Sandbox).To(Equal(targetNs.Path()))
+
 		// Call the plugins with the DEL command, deleting the veth endpoints
 		err = originalNS.Do(func(ns.NetNS) error {
 			defer GinkgoRecover()