libnetwork: extend API to support NetworkUpdate

New features in netavark/aardvark allows users to update network dns servers and all the containers attached to those networks uses updated resolvers. Following PR adds support in `libnetwork` to support * Add support for higher level `NetworkUpdate` API * Add support for `Update` exec call which can invoke netavark with a new update option added here: containers/netavark#503 Signed-off-by: Aditya R <[email protected]>
flouthoc · Dec 6, 2022 · db42c65 · db42c65
1 parent 24d7820
commit db42c65
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Showing 5 changed files with 154 additions and 9 deletions.
diff --git a/libnetwork/cni/config.go b/libnetwork/cni/config.go
@@ -15,6 +15,10 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
+func (n *cniNetwork) NetworkUpdate(name string, options types.NetworkUpdateOptions) error {
+	return fmt.Errorf("NetworkUpdate is not supported for backend CNI: %w", types.ErrInvalidArg)
+}
+
 // NetworkCreate will take a partial filled Network and fill the
 // missing fields. It creates the Network and returns the full Network.
 func (n *cniNetwork) NetworkCreate(net types.Network) (types.Network, error) {

diff --git a/libnetwork/netavark/config.go b/libnetwork/netavark/config.go
@@ -10,6 +10,7 @@ import (
 	"net"
 	"os"
 	"path/filepath"
+	"reflect"
 	"strconv"
 	"time"
 
@@ -19,6 +20,65 @@ import (
 	"github.com/containers/storage/pkg/stringid"
 )
 
+func sliceRemoveDuplicates(strList []string) []string {
+	list := make([]string, 0, len(strList))
+	for _, item := range strList {
+		if !util.StringInSlice(item, list) {
+			list = append(list, item)
+		}
+	}
+	return list
+}
+
+func (n *netavarkNetwork) commitNetwork(network *types.Network) error {
+	confPath := filepath.Join(n.networkConfigDir, network.Name+".json")
+	f, err := os.Create(confPath)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	enc := json.NewEncoder(f)
+	enc.SetIndent("", "     ")
+	err = enc.Encode(network)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (n *netavarkNetwork) NetworkUpdate(name string, options types.NetworkUpdateOptions) error {
+	n.lock.Lock()
+	defer n.lock.Unlock()
+	err := n.loadNetworks()
+	if err != nil {
+		return err
+	}
+	network, err := n.getNetwork(name)
+	if err != nil {
+		return err
+	}
+	networkDNSServersBefore := network.NetworkDNSServers
+	networkDNSServersAfter := []string{}
+	for _, server := range networkDNSServersBefore {
+		if util.StringInSlice(server, options.RemoveDNSServers) {
+			continue
+		}
+		networkDNSServersAfter = append(networkDNSServersAfter, server)
+	}
+	networkDNSServersAfter = append(networkDNSServersAfter, options.AddDNSServers...)
+	networkDNSServersAfter = sliceRemoveDuplicates(networkDNSServersAfter)
+	network.NetworkDNSServers = networkDNSServersAfter
+	if reflect.DeepEqual(networkDNSServersBefore, networkDNSServersAfter) {
+		return nil
+	}
+	err = n.commitNetwork(network)
+	if err != nil {
+		return err
+	}
+
+	return n.execUpdate(network.Name, network.NetworkDNSServers)
+}
+
 // NetworkCreate will take a partial filled Network and fill the
 // missing fields. It creates the Network and returns the full Network.
 func (n *netavarkNetwork) NetworkCreate(net types.Network) (types.Network, error) {
@@ -158,15 +218,7 @@ func (n *netavarkNetwork) networkCreate(newNetwork *types.Network, defaultNet bo
 	newNetwork.Created = time.Now()
 
 	if !defaultNet {
-		confPath := filepath.Join(n.networkConfigDir, newNetwork.Name+".json")
-		f, err := os.Create(confPath)
-		if err != nil {
-			return nil, err
-		}
-		defer f.Close()
-		enc := json.NewEncoder(f)
-		enc.SetIndent("", "     ")
-		err = enc.Encode(newNetwork)
+		err = n.commitNetwork(newNetwork)
 		if err != nil {
 			return nil, err
 		}

diff --git a/libnetwork/netavark/config_test.go b/libnetwork/netavark/config_test.go
@@ -10,6 +10,7 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/containers/common/libnetwork/netavark"
 	"github.com/containers/common/libnetwork/types"
 	"github.com/containers/common/libnetwork/util"
 	. "github.com/onsi/ginkgo/v2"
@@ -618,6 +619,78 @@ var _ = Describe("Config", func() {
 			Expect(network1.Internal).To(BeTrue())
 		})
 
+		It("update NetworkDNSServers AddDNSServers", func() {
+			libpodNet, err := netavark.NewNetworkInterface(&netavark.InitConfig{
+				NetworkConfigDir: networkConfDir,
+				NetworkRunDir:    networkConfDir,
+				NetavarkBinary:   "true",
+			})
+			if err != nil {
+				Fail("Failed to create NewNetavarkNetworkInterface")
+			}
+			network := types.Network{
+				NetworkDNSServers: []string{"8.8.8.8", "3.3.3.3"},
+				DNSEnabled:        true,
+				Name:              "test-network",
+			}
+			network1, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(BeNil())
+			Expect(network1.NetworkDNSServers).To(Equal([]string{"8.8.8.8", "3.3.3.3"}))
+			err = libpodNet.NetworkUpdate("test-network", types.NetworkUpdateOptions{AddDNSServers: []string{"8.8.8.8", "3.3.3.3", "7.7.7.7"}})
+			Expect(err).To(BeNil())
+			testNetwork, err := libpodNet.NetworkInspect("test-network")
+			Expect(err).To(BeNil())
+			Expect(testNetwork.NetworkDNSServers).To(Equal([]string{"8.8.8.8", "3.3.3.3", "7.7.7.7"}))
+		})
+
+		It("update NetworkDNSServers RemoveDNSServers", func() {
+			libpodNet, err := netavark.NewNetworkInterface(&netavark.InitConfig{
+				NetworkConfigDir: networkConfDir,
+				NetworkRunDir:    networkConfDir,
+				NetavarkBinary:   "true",
+			})
+			if err != nil {
+				Fail("Failed to create NewNetavarkNetworkInterface")
+			}
+			network := types.Network{
+				NetworkDNSServers: []string{"8.8.8.8", "3.3.3.3"},
+				DNSEnabled:        true,
+				Name:              "test-network",
+			}
+			network1, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(BeNil())
+			Expect(network1.NetworkDNSServers).To(Equal([]string{"8.8.8.8", "3.3.3.3"}))
+			err = libpodNet.NetworkUpdate("test-network", types.NetworkUpdateOptions{RemoveDNSServers: []string{"3.3.3.3"}})
+			Expect(err).To(BeNil())
+			testNetwork, err := libpodNet.NetworkInspect("test-network")
+			Expect(err).To(BeNil())
+			Expect(testNetwork.NetworkDNSServers).To(Equal([]string{"8.8.8.8"}))
+		})
+
+		It("update NetworkDNSServers Add and Remove DNSServers", func() {
+			libpodNet, err := netavark.NewNetworkInterface(&netavark.InitConfig{
+				NetworkConfigDir: networkConfDir,
+				NetworkRunDir:    networkConfDir,
+				NetavarkBinary:   "true",
+			})
+			if err != nil {
+				Fail("Failed to create NewNetavarkNetworkInterface")
+			}
+			network := types.Network{
+				NetworkDNSServers: []string{"8.8.8.8", "3.3.3.3"},
+				DNSEnabled:        true,
+				Name:              "test-network",
+			}
+			network1, err := libpodNet.NetworkCreate(network)
+			Expect(err).To(BeNil())
+			Expect(network1.NetworkDNSServers).To(Equal([]string{"8.8.8.8", "3.3.3.3"}))
+			err = libpodNet.NetworkUpdate("test-network", types.NetworkUpdateOptions{RemoveDNSServers: []string{"3.3.3.3"}, AddDNSServers: []string{"7.7.7.7"}})
+			Expect(err).To(BeNil())
+			testNetwork, err := libpodNet.NetworkInspect("test-network")
+			Expect(err).To(BeNil())
+			Expect(testNetwork.NetworkDNSServers).To(Equal([]string{"8.8.8.8", "7.7.7.7"}))
+		})
+
 		It("create network with NetworDNSServers", func() {
 			network := types.Network{
 				NetworkDNSServers: []string{"8.8.8.8", "3.3.3.3"},

diff --git a/libnetwork/netavark/run.go b/libnetwork/netavark/run.go
@@ -7,6 +7,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"strconv"
+	"strings"
 
 	"github.com/containers/common/libnetwork/internal/util"
 	"github.com/containers/common/libnetwork/types"
@@ -18,6 +19,11 @@ type netavarkOptions struct {
 	Networks map[string]*types.Network `json:"network_info"`
 }
 
+func (n *netavarkNetwork) execUpdate(networkName string, networkDNSServers []string) error {
+	retErr := n.execNetavark([]string{"update", networkName, "--network-dns-servers", strings.Join(networkDNSServers, ",")}, nil, nil)
+	return retErr
+}
+
 // Setup will setup the container network namespace. It returns
 // a map of StatusBlocks, the key is the network name.
 func (n *netavarkNetwork) Setup(namespacePath string, options types.SetupOptions) (map[string]types.StatusBlock, error) {

diff --git a/libnetwork/types/network.go b/libnetwork/types/network.go
@@ -10,6 +10,8 @@ type ContainerNetwork interface {
 	// NetworkCreate will take a partial filled Network and fill the
 	// missing fields. It creates the Network and returns the full Network.
 	NetworkCreate(Network) (Network, error)
+	// NetworkUpdate will take network name and ID and updates network DNS Servers.
+	NetworkUpdate(nameOrID string, options NetworkUpdateOptions) error
 	// NetworkRemove will remove the Network with the given name or ID.
 	NetworkRemove(nameOrID string) error
 	// NetworkList will return all known Networks. Optionally you can
@@ -70,6 +72,14 @@ type Network struct {
 	IPAMOptions map[string]string `json:"ipam_options,omitempty"`
 }
 
+// NetworkOptions for a given container.
+type NetworkUpdateOptions struct {
+	// List of custom DNS server for podman's DNS resolver.
+	// Priority order will be kept as defined by user in the configuration.
+	AddDNSServers    []string `json:"add_dns_servers,omitempty"`
+	RemoveDNSServers []string `json:"remove_dns_servers,omitempty"`
+}
+
 // IPNet is used as custom net.IPNet type to add Marshal/Unmarshal methods.
 type IPNet struct {
 	net.IPNet