prevent unpredictable results with network create|remove

due to a lack of "locking" on cni operations, we could get ourselves in trouble when doing rapid creation or removal of networks.  added a simple file lock to deal with the collision and because it is not considered a performent path, use of the file lock should be ok.  if proven otherwise in the future, some generic shared memory lock should be implemented for libpod and also used here.

moved pkog/network to libpod/network because libpod is now being pulled into the package and it has therefore lost its generic nature. this will make it easier to absorb into libpod as we try to make the network closer to core operations.

Fixes: #7807

Signed-off-by: baude <bbaude@redhat.com>

1 files changed, 0 insertions, 219 deletions

diff --git a/pkg/network/network.go b/pkg/network/network.go
deleted file mode 100644
index c4c1ff67f..000000000
--- a/pkg/network/network.go
+++ /dev/null
@@ -1,219 +0,0 @@
-package network
-
-import (
-	"encoding/json"
-	"net"
-	"os"
-
-	"github.com/containernetworking/cni/pkg/types"
-	"github.com/containernetworking/plugins/plugins/ipam/host-local/backend/allocator"
-	"github.com/containers/common/pkg/config"
-	"github.com/containers/podman/v2/libpod/define"
-	"github.com/containers/podman/v2/pkg/util"
-	"github.com/pkg/errors"
-	"github.com/sirupsen/logrus"
-)
-
-// DefaultNetworkDriver is the default network type used
-var DefaultNetworkDriver = "bridge"
-
-// SupportedNetworkDrivers describes the list of supported drivers
-var SupportedNetworkDrivers = []string{DefaultNetworkDriver}
-
-// IsSupportedDriver checks if the user provided driver is supported
-func IsSupportedDriver(driver string) error {
-	if util.StringInSlice(driver, SupportedNetworkDrivers) {
-		return nil
-	}
-	return errors.Errorf("driver '%s' is not supported", driver)
-}
-
-// GetLiveNetworks returns a slice of networks representing what the system
-// has defined as network interfaces
-func GetLiveNetworks() ([]*net.IPNet, error) {
-	addrs, err := net.InterfaceAddrs()
-	if err != nil {
-		return nil, err
-	}
-	nets := make([]*net.IPNet, 0, len(addrs))
-	for _, address := range addrs {
-		_, n, err := net.ParseCIDR(address.String())
-		if err != nil {
-			return nil, err
-		}
-		nets = append(nets, n)
-	}
-	return nets, nil
-}
-
-// GetLiveNetworkNames returns a list of network interfaces on the system
-func GetLiveNetworkNames() ([]string, error) {
-	liveInterfaces, err := net.Interfaces()
-	if err != nil {
-		return nil, err
-	}
-	interfaceNames := make([]string, 0, len(liveInterfaces))
-	for _, i := range liveInterfaces {
-		interfaceNames = append(interfaceNames, i.Name)
-	}
-	return interfaceNames, nil
-}
-
-// GetFreeNetwork looks for a free network according to existing cni configuration
-// files and network interfaces.
-func GetFreeNetwork(config *config.Config) (*net.IPNet, error) {
-	networks, err := GetNetworksFromFilesystem(config)
-	if err != nil {
-		return nil, err
-	}
-	liveNetworks, err := GetLiveNetworks()
-	if err != nil {
-		return nil, err
-	}
-	nextNetwork, err := GetDefaultPodmanNetwork()
-	if err != nil {
-		return nil, err
-	}
-	logrus.Debugf("default network is %s", nextNetwork.String())
-	for {
-		newNetwork, err := NextSubnet(nextNetwork)
-		if err != nil {
-			return nil, err
-		}
-		logrus.Debugf("checking if network %s intersects with other cni networks", nextNetwork.String())
-		if intersectsConfig, _ := networkIntersectsWithNetworks(newNetwork, allocatorToIPNets(networks)); intersectsConfig {
-			logrus.Debugf("network %s is already being used by a cni configuration", nextNetwork.String())
-			nextNetwork = newNetwork
-			continue
-		}
-		logrus.Debugf("checking if network %s intersects with any network interfaces", nextNetwork.String())
-		if intersectsLive, _ := networkIntersectsWithNetworks(newNetwork, liveNetworks); !intersectsLive {
-			break
-		}
-		logrus.Debugf("network %s is being used by a network interface", nextNetwork.String())
-		nextNetwork = newNetwork
-	}
-	return nextNetwork, nil
-}
-
-func allocatorToIPNets(networks []*allocator.Net) []*net.IPNet {
-	var nets []*net.IPNet
-	for _, network := range networks {
-		if len(network.IPAM.Ranges) > 0 {
-			// this is the new IPAM range style
-			// append each subnet from ipam the rangeset
-			for _, r := range network.IPAM.Ranges[0] {
-				nets = append(nets, newIPNetFromSubnet(r.Subnet))
-			}
-		} else {
-			//	 looks like the old, deprecated style
-			nets = append(nets, newIPNetFromSubnet(network.IPAM.Subnet))
-		}
-	}
-	return nets
-}
-
-func newIPNetFromSubnet(subnet types.IPNet) *net.IPNet {
-	n := net.IPNet{
-		IP:   subnet.IP,
-		Mask: subnet.Mask,
-	}
-	return &n
-}
-
-func networkIntersectsWithNetworks(n *net.IPNet, networklist []*net.IPNet) (bool, *net.IPNet) {
-	for _, nw := range networklist {
-		if networkIntersect(n, nw) {
-			return true, nw
-		}
-	}
-	return false, nil
-}
-
-func networkIntersect(n1, n2 *net.IPNet) bool {
-	return n2.Contains(n1.IP) || n1.Contains(n2.IP)
-}
-
-// ValidateUserNetworkIsAvailable returns via an error if a network is available
-// to be used
-func ValidateUserNetworkIsAvailable(config *config.Config, userNet *net.IPNet) error {
-	if len(userNet.IP) == 0 || len(userNet.Mask) == 0 {
-		return errors.Errorf("network %s's ip or mask cannot be empty", userNet.String())
-	}
-
-	ones, bit := userNet.Mask.Size()
-	if ones == 0 || bit == 0 {
-		return errors.Errorf("network %s's mask is invalid", userNet.String())
-	}
-
-	networks, err := GetNetworksFromFilesystem(config)
-	if err != nil {
-		return err
-	}
-	liveNetworks, err := GetLiveNetworks()
-	if err != nil {
-		return err
-	}
-	logrus.Debugf("checking if network %s exists in cni networks", userNet.String())
-	if intersectsConfig, _ := networkIntersectsWithNetworks(userNet, allocatorToIPNets(networks)); intersectsConfig {
-		return errors.Errorf("network %s is already being used by a cni configuration", userNet.String())
-	}
-	logrus.Debugf("checking if network %s exists in any network interfaces", userNet.String())
-	if intersectsLive, _ := networkIntersectsWithNetworks(userNet, liveNetworks); intersectsLive {
-		return errors.Errorf("network %s is being used by a network interface", userNet.String())
-	}
-	return nil
-}
-
-// RemoveNetwork removes a given network by name.  If the network has container associated with it, that
-// must be handled outside the context of this.
-func RemoveNetwork(config *config.Config, name string) error {
-	cniPath, err := GetCNIConfigPathByName(config, name)
-	if err != nil {
-		return err
-	}
-	// Before we delete the configuration file, we need to make sure we can read and parse
-	// it to get the network interface name so we can remove that too
-	interfaceName, err := GetInterfaceNameFromConfig(cniPath)
-	if err != nil {
-		return errors.Wrapf(err, "failed to find network interface name in %q", cniPath)
-	}
-	liveNetworkNames, err := GetLiveNetworkNames()
-	if err != nil {
-		return errors.Wrapf(err, "failed to get live network names")
-	}
-	if util.StringInSlice(interfaceName, liveNetworkNames) {
-		if err := RemoveInterface(interfaceName); err != nil {
-			return errors.Wrapf(err, "failed to delete the network interface %q", interfaceName)
-		}
-	}
-	// Remove the configuration file
-	if err := os.Remove(cniPath); err != nil {
-		return errors.Wrapf(err, "failed to remove network configuration file %q", cniPath)
-	}
-	return nil
-}
-
-// InspectNetwork reads a CNI config and returns its configuration
-func InspectNetwork(config *config.Config, name string) (map[string]interface{}, error) {
-	b, err := ReadRawCNIConfByName(config, name)
-	if err != nil {
-		return nil, err
-	}
-	rawList := make(map[string]interface{})
-	err = json.Unmarshal(b, &rawList)
-	return rawList, err
-}
-
-// Exists says whether a given network exists or not; it meant
-// specifically for restful responses so 404s can be used
-func Exists(config *config.Config, name string) (bool, error) {
-	_, err := ReadRawCNIConfByName(config, name)
-	if err != nil {
-		if errors.Cause(err) == define.ErrNoSuchNetwork {
-			return false, nil
-		}
-		return false, err
-	}
-	return true, nil
-}