netavark network interface

Implement a new network interface for netavark.
For now only bridge networking is supported.
The interface can create/list/inspect/remove networks. For setup and
teardown netavark will be invoked.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

1 files changed, 275 insertions, 0 deletions

diff --git a/libpod/network/netavark/network.go b/libpod/network/netavark/network.go
new file mode 100644
index 000000000..aa7dc8183
--- /dev/null
+++ b/libpod/network/netavark/network.go
@@ -0,0 +1,275 @@
+// +build linux
+
+package netavark
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/containers/podman/v3/libpod/define"
+	"github.com/containers/podman/v3/libpod/network/internal/util"
+	"github.com/containers/podman/v3/libpod/network/types"
+	"github.com/containers/storage/pkg/lockfile"
+	"github.com/pkg/errors"
+	"github.com/sirupsen/logrus"
+)
+
+type netavarkNetwork struct {
+	// networkConfigDir is directory where the network config files are stored.
+	networkConfigDir string
+
+	// netavarkBinary is the path to the netavark binary.
+	netavarkBinary string
+
+	// defaultNetwork is the name for the default network.
+	defaultNetwork string
+	// defaultSubnet is the default subnet for the default network.
+	defaultSubnet types.IPNet
+
+	// isMachine describes whenever podman runs in a podman machine environment.
+	isMachine bool
+
+	// lock is a internal lock for critical operations
+	lock lockfile.Locker
+
+	// modTime is the timestamp when the config dir was modified
+	modTime time.Time
+
+	// networks is a map with loaded networks, the key is the network name
+	networks map[string]*types.Network
+}
+
+type InitConfig struct {
+	// NetworkConfigDir is directory where the network config files are stored.
+	NetworkConfigDir string
+
+	// NetavarkBinary is the path to the netavark binary.
+	NetavarkBinary string
+
+	// DefaultNetwork is the name for the default network.
+	DefaultNetwork string
+	// DefaultSubnet is the default subnet for the default network.
+	DefaultSubnet string
+
+	// IsMachine describes whenever podman runs in a podman machine environment.
+	IsMachine bool
+
+	// LockFile is the path to lock file.
+	LockFile string
+}
+
+// NewNetworkInterface creates the ContainerNetwork interface for the netavark backend.
+// Note: The networks are not loaded from disk until a method is called.
+func NewNetworkInterface(conf InitConfig) (types.ContainerNetwork, error) {
+	// TODO: consider using a shared memory lock
+	lock, err := lockfile.GetLockfile(conf.LockFile)
+	if err != nil {
+		return nil, err
+	}
+
+	defaultNetworkName := conf.DefaultNetwork
+	if defaultNetworkName == "" {
+		defaultNetworkName = types.DefaultNetworkName
+	}
+
+	defaultSubnet := conf.DefaultSubnet
+	if defaultSubnet == "" {
+		defaultSubnet = types.DefaultSubnet
+	}
+	defaultNet, err := types.ParseCIDR(defaultSubnet)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to parse default subnet")
+	}
+
+	n := &netavarkNetwork{
+		networkConfigDir: conf.NetworkConfigDir,
+		netavarkBinary:   conf.NetavarkBinary,
+		defaultNetwork:   defaultNetworkName,
+		defaultSubnet:    defaultNet,
+		isMachine:        conf.IsMachine,
+		lock:             lock,
+	}
+
+	return n, nil
+}
+
+// Drivers will return the list of supported network drivers
+// for this interface.
+func (n *netavarkNetwork) Drivers() []string {
+	return []string{types.BridgeNetworkDriver}
+}
+
+func (n *netavarkNetwork) loadNetworks() error {
+	// check the mod time of the config dir
+	f, err := os.Stat(n.networkConfigDir)
+	if err != nil {
+		return err
+	}
+	modTime := f.ModTime()
+
+	// skip loading networks if they are already loaded and
+	// if the config dir was not modified since the last call
+	if n.networks != nil && modTime.Equal(n.modTime) {
+		return nil
+	}
+	// make sure the remove all networks before we reload them
+	n.networks = nil
+	n.modTime = modTime
+
+	files, err := ioutil.ReadDir(n.networkConfigDir)
+	if err != nil && !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+
+	networks := make(map[string]*types.Network, len(files))
+	for _, f := range files {
+		if f.IsDir() {
+			continue
+		}
+		if filepath.Ext(f.Name()) != ".json" {
+			continue
+		}
+
+		path := filepath.Join(n.networkConfigDir, f.Name())
+		file, err := os.Open(path)
+		if err != nil {
+			// do not log ENOENT errors
+			if !errors.Is(err, os.ErrNotExist) {
+				logrus.Warnf("Error loading network config file %q: %v", path, err)
+			}
+			continue
+		}
+		network := new(types.Network)
+		err = json.NewDecoder(file).Decode(network)
+		if err != nil {
+			logrus.Warnf("Error reading network config file %q: %v", path, err)
+			continue
+		}
+
+		// check that the filename matches the network name
+		if network.Name+".json" != f.Name() {
+			logrus.Warnf("Network config name %q does not match file name %q, skipping", network.Name, f.Name())
+			continue
+		}
+
+		if !define.NameRegex.MatchString(network.Name) {
+			logrus.Warnf("Network config %q has invalid name: %q, skipping: %v", path, network.Name, define.RegexError)
+			continue
+		}
+
+		err = parseNetwork(network)
+		if err != nil {
+			logrus.Warnf("Network config %q could not be parsed, skipping: %v", path, err)
+			continue
+		}
+
+		logrus.Debugf("Successfully loaded network %s: %v", network.Name, network)
+		networks[network.Name] = network
+	}
+
+	// create the default network in memory if it did not exists on disk
+	if networks[n.defaultNetwork] == nil {
+		networkInfo, err := n.createDefaultNetwork()
+		if err != nil {
+			return errors.Wrapf(err, "failed to create default network %s", n.defaultNetwork)
+		}
+		networks[n.defaultNetwork] = networkInfo
+	}
+	logrus.Debugf("Successfully loaded %d networks", len(networks))
+	n.networks = networks
+	return nil
+}
+
+func parseNetwork(network *types.Network) error {
+	if network.Labels == nil {
+		network.Labels = map[string]string{}
+	}
+	if network.Options == nil {
+		network.Options = map[string]string{}
+	}
+	if network.IPAMOptions == nil {
+		network.IPAMOptions = map[string]string{}
+	}
+
+	if len(network.ID) != 64 {
+		return errors.Errorf("invalid network ID %q", network.ID)
+	}
+
+	return util.ValidateSubnets(network, nil)
+}
+
+func (n *netavarkNetwork) createDefaultNetwork() (*types.Network, error) {
+	net := types.Network{
+		Name:             n.defaultNetwork,
+		NetworkInterface: defaultBridgeName + "0",
+		// Important do not change this ID
+		ID:     "2f259bab93aaaaa2542ba43ef33eb990d0999ee1b9924b557b7be53c0b7a1bb9",
+		Driver: types.BridgeNetworkDriver,
+		Subnets: []types.Subnet{
+			{Subnet: n.defaultSubnet},
+		},
+	}
+	return n.networkCreate(net, true)
+}
+
+// getNetwork will lookup a network by name or ID. It returns an
+// error when no network was found or when more than one network
+// with the given (partial) ID exists.
+// getNetwork will read from the networks map, therefore the caller
+// must ensure that n.lock is locked before using it.
+func (n *netavarkNetwork) getNetwork(nameOrID string) (*types.Network, error) {
+	// fast path check the map key, this will only work for names
+	if val, ok := n.networks[nameOrID]; ok {
+		return val, nil
+	}
+	// If there was no match we might got a full or partial ID.
+	var net *types.Network
+	for _, val := range n.networks {
+		// This should not happen because we already looked up the map by name but check anyway.
+		if val.Name == nameOrID {
+			return val, nil
+		}
+
+		if strings.HasPrefix(val.ID, nameOrID) {
+			if net != nil {
+				return nil, errors.Errorf("more than one result for network ID %s", nameOrID)
+			}
+			net = val
+		}
+	}
+	if net != nil {
+		return net, nil
+	}
+	return nil, errors.Wrapf(define.ErrNoSuchNetwork, "unable to find network with name or ID %s", nameOrID)
+}
+
+// Implement the NetUtil interface for easy code sharing with other network interfaces.
+
+// ForEach call the given function for each network
+func (n *netavarkNetwork) ForEach(run func(types.Network)) {
+	for _, val := range n.networks {
+		run(*val)
+	}
+}
+
+// Len return the number of networks
+func (n *netavarkNetwork) Len() int {
+	return len(n.networks)
+}
+
+// DefaultInterfaceName return the default cni bridge name, must be suffixed with a number.
+func (n *netavarkNetwork) DefaultInterfaceName() string {
+	return defaultBridgeName
+}
+
+func (n *netavarkNetwork) Network(nameOrID string) (*types.Network, error) {
+	network, err := n.getNetwork(nameOrID)
+	if err != nil {
+		return nil, err
+	}
+	return network, nil
+}