libnetwork/netavark: allow network create with no ipam driver

Network create now uses the ipam driver. This allows the user to configure the ipam driver manually instead of choosing a fixed default. If the ipam driver is `none` no ips will be assigned to this container. This means that only the interfaces are created. This will require a patch in netavark since it rejects the config when no static ips are provided. Ref containers/podman#13521 Signed-off-by: Paul Holzinger <[email protected]>
containers · Mar 17, 2022 · cb62f29 · cb62f29
1 parent 6bcfebf
commit cb62f29
Show file tree

Hide file tree

Showing 4 changed files with 182 additions and 6 deletions.
diff --git a/libnetwork/netavark/config.go b/libnetwork/netavark/config.go
@@ -66,6 +66,11 @@ func (n *netavarkNetwork) networkCreate(newNetwork *types.Network, defaultNet bo
 		return nil, err
 	}
 
+	err = validateIPAMDriver(newNetwork)
+	if err != nil {
+		return nil, err
+	}
+
 	// Only get the used networks for validation if we do not create the default network.
 	// The default network should not be validated against used subnets, we have to ensure
 	// that this network can always be created even when a subnet is already used on the host.
@@ -152,10 +157,19 @@ func createMacvlan(network *types.Network) error {
 			return errors.Errorf("parent interface %s does not exist", network.NetworkInterface)
 		}
 	}
-	if len(network.Subnets) == 0 {
-		return errors.Errorf("macvlan driver needs at least one subnet specified, DHCP is not supported with netavark")
+
+	// we already validated the drivers before so we just have to set the default here
+	switch network.IPAMOptions[types.Driver] {
+	case "":
+		if len(network.Subnets) == 0 {
+			return errors.Errorf("macvlan driver needs at least one subnet specified, DHCP is not yet supported with netavark")
+		}
+		network.IPAMOptions[types.Driver] = types.HostLocalIPAMDriver
+	case types.HostLocalIPAMDriver:
+		if len(network.Subnets) == 0 {
+			return errors.Errorf("macvlan driver needs at least one subnet specified, when the host-local ipam driver is set")
+		}
 	}
-	network.IPAMOptions[types.Driver] = types.HostLocalIPAMDriver
 
 	// validate the given options, we do not need them but just check to make sure they are valid
 	for key, value := range network.Options {
@@ -245,3 +259,19 @@ func (n *netavarkNetwork) NetworkInspect(nameOrID string) (types.Network, error)
 	}
 	return *network, nil
 }
+
+func validateIPAMDriver(n *types.Network) error {
+	ipamDriver := n.IPAMOptions[types.Driver]
+	switch ipamDriver {
+	case "", types.HostLocalIPAMDriver:
+	case types.NoneIPAMDriver:
+		if len(n.Subnets) > 0 {
+			return errors.New("none ipam driver is set but subnets are given")
+		}
+	case types.DHCPIPAMDriver:
+		return errors.New("dhcp ipam driver is not yet supported with netavark")
+	default:
+		return errors.Errorf("unsupported ipam driver %q", ipamDriver)
+	}
+	return nil
+}
diff --git a/libnetwork/netavark/config_test.go b/libnetwork/netavark/config_test.go
@@ -793,7 +793,7 @@ var _ = Describe("Config", func() {
 			network := types.Network{Driver: "macvlan"}
 			_, err := libpodNet.NetworkCreate(network)
 			Expect(err).To(HaveOccurred())
-			Expect(err.Error()).To(Equal("macvlan driver needs at least one subnet specified, DHCP is not supported with netavark"))
+			Expect(err.Error()).To(Equal("macvlan driver needs at least one subnet specified, DHCP is not yet supported with netavark"))
 		})
 
 		It("create macvlan config with internal", func() {
@@ -956,6 +956,69 @@ var _ = Describe("Config", func() {
 			Expect(network1.Options).To(HaveKeyWithValue("mtu", "9000"))
 		})
 
+		It("create bridge config with none ipam driver", func() {
+			network := types.Network{
+				Driver: "bridge",
+				IPAMOptions: map[string]string{
+					"driver": "none",
+				},
+			}
+			network1, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(BeNil())
+			Expect(network1.Driver).To(Equal("bridge"))
+			Expect(network1.IPAMOptions).ToNot(BeEmpty())
+			Expect(network1.IPAMOptions).To(HaveKeyWithValue("driver", "none"))
+			Expect(network1.Subnets).To(HaveLen(0))
+
+			// reload configs from disk
+			libpodNet, err = getNetworkInterface(networkConfDir)
+			Expect(err).To(BeNil())
+
+			network2, err := libpodNet.NetworkInspect(network1.Name)
+			Expect(err).To(BeNil())
+			EqualNetwork(network2, network1)
+		})
+
+		It("create bridge config with none ipam driver and subnets", func() {
+			subnet := "10.1.0.0/24"
+			n, _ := types.ParseCIDR(subnet)
+			network := types.Network{
+				Driver: "bridge",
+				IPAMOptions: map[string]string{
+					"driver": "none",
+				},
+				Subnets: []types.Subnet{
+					{Subnet: n},
+				},
+			}
+			_, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(HaveOccurred())
+			Expect(err.Error()).To(Equal("none ipam driver is set but subnets are given"))
+		})
+
+		It("create macvlan config with none ipam driver", func() {
+			network := types.Network{
+				Driver: "macvlan",
+				IPAMOptions: map[string]string{
+					"driver": "none",
+				},
+			}
+			network1, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(BeNil())
+			Expect(network1.Driver).To(Equal("macvlan"))
+			Expect(network1.IPAMOptions).ToNot(BeEmpty())
+			Expect(network1.IPAMOptions).To(HaveKeyWithValue("driver", "none"))
+			Expect(network1.Subnets).To(HaveLen(0))
+
+			// reload configs from disk
+			libpodNet, err = getNetworkInterface(networkConfDir)
+			Expect(err).To(BeNil())
+
+			network2, err := libpodNet.NetworkInspect(network1.Name)
+			Expect(err).To(BeNil())
+			EqualNetwork(network2, network1)
+		})
+
 	})
 
 	Context("network load valid existing ones", func() {

diff --git a/libnetwork/netavark/ipam_test.go b/libnetwork/netavark/ipam_test.go
@@ -398,10 +398,10 @@ var _ = Describe("IPAM", func() {
 		}
 	})
 
-	It("ipam with dhcp driver should not set ips", func() {
+	It("ipam with none driver should not set ips", func() {
 		network, err := networkInterface.NetworkCreate(types.Network{
 			IPAMOptions: map[string]string{
-				"driver": types.DHCPIPAMDriver,
+				"driver": types.NoneIPAMDriver,
 			},
 		})
 		Expect(err).ToNot(HaveOccurred())

diff --git a/libnetwork/netavark/run_test.go b/libnetwork/netavark/run_test.go
@@ -699,6 +699,89 @@ var _ = Describe("run netavark", func() {
 			Expect(err.Error()).To(ContainSubstring("interface eth0 already exists on container namespace"))
 		})
 	})
+
+	It("setup ipam driver none network", func() {
+		runTest(func() {
+			network := types.Network{
+				IPAMOptions: map[string]string{
+					types.Driver: types.NoneIPAMDriver,
+				},
+			}
+			network1, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(BeNil())
+
+			intName1 := "eth0"
+			netName1 := network1.Name
+
+			setupOpts := types.SetupOptions{
+				NetworkOptions: types.NetworkOptions{
+					ContainerID: stringid.GenerateNonCryptoID(),
+					Networks: map[string]types.PerNetworkOptions{
+						netName1: {
+							InterfaceName: intName1,
+						},
+					},
+				},
+			}
+
+			res, err := libpodNet.Setup(netNSContainer.Path(), setupOpts)
+			Expect(err).To(BeNil())
+			Expect(res).To(HaveLen(1))
+
+			Expect(res).To(HaveKey(netName1))
+			Expect(res[netName1].Interfaces).To(HaveKey(intName1))
+			Expect(res[netName1].Interfaces[intName1].Subnets).To(HaveLen(0))
+			macInt1 := res[netName1].Interfaces[intName1].MacAddress
+			Expect(macInt1).To(HaveLen(6))
+
+			// check in the container namespace if the settings are applied
+			err = netNSContainer.Do(func(_ ns.NetNS) error {
+				defer GinkgoRecover()
+				i, err := net.InterfaceByName(intName1)
+				Expect(err).To(BeNil())
+				Expect(i.Name).To(Equal(intName1))
+				Expect(i.HardwareAddr).To(Equal(net.HardwareAddr(macInt1)))
+				addrs, err := i.Addrs()
+				Expect(err).To(BeNil())
+				// we still have the ipv6 link local address
+				Expect(addrs).To(HaveLen(1))
+				addr, ok := addrs[0].(*net.IPNet)
+				Expect(ok).To(BeTrue(), "cast address to ipnet")
+				// make sure we are link local
+				Expect(addr.IP.IsLinkLocalUnicast()).To(BeTrue(), "ip is link local address")
+
+				// check loopback adapter
+				i, err = net.InterfaceByName("lo")
+				Expect(err).To(BeNil())
+				Expect(i.Name).To(Equal("lo"))
+				Expect(i.Flags & net.FlagLoopback).To(Equal(net.FlagLoopback))
+				Expect(i.Flags&net.FlagUp).To(Equal(net.FlagUp), "Loopback adapter should be up")
+				return nil
+			})
+			Expect(err).To(BeNil())
+
+			err = libpodNet.Teardown(netNSContainer.Path(), types.TeardownOptions(setupOpts))
+			Expect(err).To(BeNil())
+
+			// check in the container namespace that the interface is removed
+			err = netNSContainer.Do(func(_ ns.NetNS) error {
+				defer GinkgoRecover()
+				_, err := net.InterfaceByName(intName1)
+				Expect(err).To(HaveOccurred())
+
+				// check that only the loopback adapter is left
+				ints, err := net.Interfaces()
+				Expect(err).To(BeNil())
+				Expect(ints).To(HaveLen(1))
+				Expect(ints[0].Name).To(Equal("lo"))
+				Expect(ints[0].Flags & net.FlagLoopback).To(Equal(net.FlagLoopback))
+				Expect(ints[0].Flags&net.FlagUp).To(Equal(net.FlagUp), "Loopback adapter should be up")
+
+				return nil
+			})
+			Expect(err).To(BeNil())
+		})
+	})
 })
 
 func runNetListener(wg *sync.WaitGroup, protocol, ip string, port int, expectedData string) {