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, 2 insertions, 174 deletions

diff --git a/pkg/domain/infra/abi/network.go b/pkg/domain/infra/abi/network.go
index 5acfea853..f40df828a 100644
--- a/pkg/domain/infra/abi/network.go
+++ b/pkg/domain/infra/abi/network.go
@@ -2,19 +2,13 @@ package abi
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
-	"io/ioutil"
-	"os"
-	"path/filepath"
 	"strings"
 
 	"github.com/containernetworking/cni/libcni"
-	cniversion "github.com/containernetworking/cni/pkg/version"
-	"github.com/containers/podman/v2/libpod"
 	"github.com/containers/podman/v2/libpod/define"
+	"github.com/containers/podman/v2/libpod/network"
 	"github.com/containers/podman/v2/pkg/domain/entities"
-	"github.com/containers/podman/v2/pkg/network"
 	"github.com/containers/podman/v2/pkg/util"
 	"github.com/pkg/errors"
 )
@@ -111,173 +105,7 @@ func (ic *ContainerEngine) NetworkRm(ctx context.Context, namesOrIds []string, o
 }
 
 func (ic *ContainerEngine) NetworkCreate(ctx context.Context, name string, options entities.NetworkCreateOptions) (*entities.NetworkCreateReport, error) {
-	var (
-		err      error
-		fileName string
-	)
-	if len(options.MacVLAN) > 0 {
-		fileName, err = createMacVLAN(ic.Libpod, name, options)
-	} else {
-		fileName, err = createBridge(ic.Libpod, name, options)
-	}
-	if err != nil {
-		return nil, err
-	}
-	return &entities.NetworkCreateReport{Filename: fileName}, nil
-}
-
-// createBridge creates a CNI network
-func createBridge(r *libpod.Runtime, name string, options entities.NetworkCreateOptions) (string, error) {
-	isGateway := true
-	ipMasq := true
-	subnet := &options.Subnet
-	ipRange := options.Range
-	runtimeConfig, err := r.GetConfig()
-	if err != nil {
-		return "", err
-	}
-	// if range is provided, make sure it is "in" network
-	if subnet.IP != nil {
-		// if network is provided, does it conflict with existing CNI or live networks
-		err = network.ValidateUserNetworkIsAvailable(runtimeConfig, subnet)
-	} else {
-		// if no network is provided, figure out network
-		subnet, err = network.GetFreeNetwork(runtimeConfig)
-	}
-	if err != nil {
-		return "", err
-	}
-	gateway := options.Gateway
-	if gateway == nil {
-		// if no gateway is provided, provide it as first ip of network
-		gateway = network.CalcGatewayIP(subnet)
-	}
-	// if network is provided and if gateway is provided, make sure it is "in" network
-	if options.Subnet.IP != nil && options.Gateway != nil {
-		if !subnet.Contains(gateway) {
-			return "", errors.Errorf("gateway %s is not in valid for subnet %s", gateway.String(), subnet.String())
-		}
-	}
-	if options.Internal {
-		isGateway = false
-		ipMasq = false
-	}
-
-	// if a range is given, we need to ensure it is "in" the network range.
-	if options.Range.IP != nil {
-		if options.Subnet.IP == nil {
-			return "", errors.New("you must define a subnet range to define an ip-range")
-		}
-		firstIP, err := network.FirstIPInSubnet(&options.Range)
-		if err != nil {
-			return "", err
-		}
-		lastIP, err := network.LastIPInSubnet(&options.Range)
-		if err != nil {
-			return "", err
-		}
-		if !subnet.Contains(firstIP) || !subnet.Contains(lastIP) {
-			return "", errors.Errorf("the ip range %s does not fall within the subnet range %s", options.Range.String(), subnet.String())
-		}
-	}
-	bridgeDeviceName, err := network.GetFreeDeviceName(runtimeConfig)
-	if err != nil {
-		return "", err
-	}
-
-	if len(name) > 0 {
-		netNames, err := network.GetNetworkNamesFromFileSystem(runtimeConfig)
-		if err != nil {
-			return "", err
-		}
-		if util.StringInSlice(name, netNames) {
-			return "", errors.Errorf("the network name %s is already used", name)
-		}
-	} else {
-		// If no name is given, we give the name of the bridge device
-		name = bridgeDeviceName
-	}
-
-	ncList := network.NewNcList(name, cniversion.Current())
-	var plugins []network.CNIPlugins
-	var routes []network.IPAMRoute
-
-	defaultRoute, err := network.NewIPAMDefaultRoute(network.IsIPv6(subnet.IP))
-	if err != nil {
-		return "", err
-	}
-	routes = append(routes, defaultRoute)
-	ipamConfig, err := network.NewIPAMHostLocalConf(subnet, routes, ipRange, gateway)
-	if err != nil {
-		return "", err
-	}
-
-	// TODO need to iron out the role of isDefaultGW and IPMasq
-	bridge := network.NewHostLocalBridge(bridgeDeviceName, isGateway, false, ipMasq, ipamConfig)
-	plugins = append(plugins, bridge)
-	plugins = append(plugins, network.NewPortMapPlugin())
-	plugins = append(plugins, network.NewFirewallPlugin())
-	// if we find the dnsname plugin, we add configuration for it
-	if network.HasDNSNamePlugin(runtimeConfig.Network.CNIPluginDirs) && !options.DisableDNS {
-		// Note: in the future we might like to allow for dynamic domain names
-		plugins = append(plugins, network.NewDNSNamePlugin(network.DefaultPodmanDomainName))
-	}
-	ncList["plugins"] = plugins
-	b, err := json.MarshalIndent(ncList, "", "   ")
-	if err != nil {
-		return "", err
-	}
-	if err := os.MkdirAll(network.GetCNIConfDir(runtimeConfig), 0755); err != nil {
-		return "", err
-	}
-	cniPathName := filepath.Join(network.GetCNIConfDir(runtimeConfig), fmt.Sprintf("%s.conflist", name))
-	err = ioutil.WriteFile(cniPathName, b, 0644)
-	return cniPathName, err
-}
-
-func createMacVLAN(r *libpod.Runtime, name string, options entities.NetworkCreateOptions) (string, error) {
-	var (
-		plugins []network.CNIPlugins
-	)
-	liveNetNames, err := network.GetLiveNetworkNames()
-	if err != nil {
-		return "", err
-	}
-
-	config, err := r.GetConfig()
-	if err != nil {
-		return "", err
-	}
-
-	// Make sure the host-device exists
-	if !util.StringInSlice(options.MacVLAN, liveNetNames) {
-		return "", errors.Errorf("failed to find network interface %q", options.MacVLAN)
-	}
-	if len(name) > 0 {
-		netNames, err := network.GetNetworkNamesFromFileSystem(config)
-		if err != nil {
-			return "", err
-		}
-		if util.StringInSlice(name, netNames) {
-			return "", errors.Errorf("the network name %s is already used", name)
-		}
-	} else {
-		name, err = network.GetFreeDeviceName(config)
-		if err != nil {
-			return "", err
-		}
-	}
-	ncList := network.NewNcList(name, cniversion.Current())
-	macvlan := network.NewMacVLANPlugin(options.MacVLAN)
-	plugins = append(plugins, macvlan)
-	ncList["plugins"] = plugins
-	b, err := json.MarshalIndent(ncList, "", "   ")
-	if err != nil {
-		return "", err
-	}
-	cniPathName := filepath.Join(network.GetCNIConfDir(config), fmt.Sprintf("%s.conflist", name))
-	err = ioutil.WriteFile(cniPathName, b, 0644)
-	return cniPathName, err
+	return network.Create(name, options, ic.Libpod)
 }
 
 func ifPassesFilterTest(netconf *libcni.NetworkConfigList, filter []string) bool {