1 files changed, 225 insertions, 0 deletions
diff --git a/libpod/network/network.go b/libpod/network/network.go
new file mode 100644
index 000000000..7327a1a7d
--- /dev/null
+++ b/libpod/network/network.go
@@ -0,0 +1,225 @@
+package network
+
+import (
+	"encoding/json"
+	"net"
+	"os"
+	"path/filepath"
+
+	"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 {
+	l, err := acquireCNILock(filepath.Join(config.Engine.TmpDir, LockFileName))
+	if err != nil {
+		return err
+	}
+	defer l.releaseCNILock()
+	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
+}