Vendoring Libnetwork library

- adding conntrack flush fix for docker/docker#8795

Signed-off-by: Flavio Crisciani <flavio.crisciani@docker.com>

vendor.conf

@@ -24,7 +24,7 @@ github.com/RackSec/srslog 456df3a81436d29ba874f3590eeeee25d666f8a5
 github.com/imdario/mergo 0.2.1
 
 #get libnetwork packages
-github.com/docker/libnetwork ab8f7e61743aa7e54c5d0dad0551543adadc33cf
+github.com/docker/libnetwork b13e0604016a4944025aaff521d9c125850b0d04
 github.com/docker/go-events 18b43f1bc85d9cdd42c05a6cd2d444c7a200a894
 github.com/armon/go-radix e39d623f12e8e41c7b5529e9a9dd67a1e2261f80
 github.com/armon/go-metrics eb0af217e5e9747e41dd5303755356b62d28e3ec

vendor/github.com/docker/libnetwork/controller.go

@@ -47,6 +47,7 @@ import (
 	"container/heap"
 	"fmt"
 	"net"
+	"path/filepath"
 	"strings"
 	"sync"
 	"time"
@@ -979,6 +980,8 @@ func (c *controller) NewSandbox(containerID string, options ...SandboxOption) (s
 
 	if sb.ingress {
 		c.ingressSandbox = sb
+		sb.config.hostsPath = filepath.Join(c.cfg.Daemon.DataDir, "/network/files/hosts")
+		sb.config.resolvConfPath = filepath.Join(c.cfg.Daemon.DataDir, "/network/files/resolv.conf")
 		sb.id = "ingress_sbox"
 	}
 	c.Unlock()

vendor/github.com/docker/libnetwork/drivers/bridge/bridge.go

@@ -1346,6 +1346,13 @@ func (d *driver) RevokeExternalConnectivity(nid, eid string) error {
 
 	endpoint.portMapping = nil
 
+	// Clean the connection tracker state of the host for the specific endpoint
+	// The host kernel keeps track of the connections (TCP and UDP), so if a new endpoint gets the same IP of
+	// this one (that is going down), is possible that some of the packets would not be routed correctly inside
+	// the new endpoint
+	// Deeper details: https://github.com/docker/docker/issues/8795
+	clearEndpointConnections(d.nlh, endpoint)
+
 	if err = d.storeUpdate(endpoint); err != nil {
 		return fmt.Errorf("failed to update bridge endpoint %s to store: %v", endpoint.id[0:7], err)
 	}

vendor/github.com/docker/libnetwork/drivers/bridge/setup_ip_tables.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/Sirupsen/logrus"
 	"github.com/docker/libnetwork/iptables"
+	"github.com/vishvananda/netlink"
 )
 
 // DockerChain: DOCKER iptable chain name
@@ -348,3 +349,15 @@ func setupInternalNetworkRules(bridgeIface string, addr net.Addr, icc, insert bo
 	}
 	return nil
 }
+
+func clearEndpointConnections(nlh *netlink.Handle, ep *bridgeEndpoint) {
+	var ipv4List []net.IP
+	var ipv6List []net.IP
+	if ep.addr != nil {
+		ipv4List = append(ipv4List, ep.addr.IP)
+	}
+	if ep.addrv6 != nil {
+		ipv6List = append(ipv6List, ep.addrv6.IP)
+	}
+	iptables.DeleteConntrackEntries(nlh, ipv4List, ipv6List)
+}

vendor/github.com/docker/libnetwork/endpoint.go

@@ -665,7 +665,7 @@ func (ep *endpoint) hasInterface(iName string) bool {
 
 func (ep *endpoint) Leave(sbox Sandbox, options ...EndpointOption) error {
 	if sbox == nil || sbox.ID() == "" || sbox.Key() == "" {
-		return types.BadRequestErrorf("invalid Sandbox passed to enpoint leave: %v", sbox)
+		return types.BadRequestErrorf("invalid Sandbox passed to endpoint leave: %v", sbox)
 	}
 
 	sb, ok := sbox.(*sandbox)

vendor/github.com/docker/libnetwork/error.go

@@ -129,7 +129,7 @@ type ActiveEndpointsError struct {
 }
 
 func (aee *ActiveEndpointsError) Error() string {
-	return fmt.Sprintf("network %s has active endpoints", aee.name)
+	return fmt.Sprintf("network %s id %s has active endpoints", aee.name, aee.id)
 }
 
 // Forbidden denotes the type of this error

vendor/github.com/docker/libnetwork/iptables/conntrack.go

@@ -0,0 +1,59 @@
+package iptables
+
+import (
+	"errors"
+	"net"
+	"syscall"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/vishvananda/netlink"
+)
+
+var (
+	// ErrConntrackNotConfigurable means that conntrack module is not loaded or does not have the netlink module loaded
+	ErrConntrackNotConfigurable = errors.New("conntrack is not available")
+)
+
+// IsConntrackProgrammable returns true if the handle supports the NETLINK_NETFILTER and the base modules are loaded
+func IsConntrackProgrammable(nlh *netlink.Handle) bool {
+	return nlh.SupportsNetlinkFamily(syscall.NETLINK_NETFILTER)
+}
+
+// DeleteConntrackEntries deletes all the conntrack connections on the host for the specified IP
+// Returns the number of flows deleted for IPv4, IPv6 else error
+func DeleteConntrackEntries(nlh *netlink.Handle, ipv4List []net.IP, ipv6List []net.IP) (uint, uint, error) {
+	if !IsConntrackProgrammable(nlh) {
+		return 0, 0, ErrConntrackNotConfigurable
+	}
+
+	var totalIPv4FlowPurged uint
+	for _, ipAddress := range ipv4List {
+		flowPurged, err := purgeConntrackState(nlh, syscall.AF_INET, ipAddress)
+		if err != nil {
+			logrus.Warnf("Failed to delete conntrack state for %s: %v", ipAddress, err)
+			continue
+		}
+		totalIPv4FlowPurged += flowPurged
+	}
+
+	var totalIPv6FlowPurged uint
+	for _, ipAddress := range ipv6List {
+		flowPurged, err := purgeConntrackState(nlh, syscall.AF_INET6, ipAddress)
+		if err != nil {
+			logrus.Warnf("Failed to delete conntrack state for %s: %v", ipAddress, err)
+			continue
+		}
+		totalIPv6FlowPurged += flowPurged
+	}
+
+	logrus.Debugf("DeleteConntrackEntries purged ipv4:%d, ipv6:%d", totalIPv4FlowPurged, totalIPv6FlowPurged)
+	return totalIPv4FlowPurged, totalIPv6FlowPurged, nil
+}
+
+func purgeConntrackState(nlh *netlink.Handle, family netlink.InetFamily, ipAddress net.IP) (uint, error) {
+	filter := &netlink.ConntrackFilter{}
+	// NOTE: doing the flush using the ipAddress is safe because today there cannot be multiple networks with the same subnet
+	// so it will not be possible to flush flows that are of other containers
+	filter.AddIP(netlink.ConntrackNatAnyIP, ipAddress)
+	return nlh.ConntrackDeleteFilter(netlink.ConntrackTable, family, filter)
+}

vendor/github.com/docker/libnetwork/iptables/iptables.go

@@ -100,14 +100,14 @@ func detectIptables() {
 	supportsCOpt = supportsCOption(mj, mn, mc)
 }
 
-func initIptables() {
+func initDependencies() {
 	probe()
 	initFirewalld()
 	detectIptables()
 }
 
 func initCheck() error {
-	initOnce.Do(initIptables)
+	initOnce.Do(initDependencies)
 
 	if iptablesPath == "" {
 		return ErrIptablesNotFound

vendor/github.com/docker/libnetwork/networkdb/delegate.go

@@ -88,12 +88,25 @@ func (nDB *NetworkDB) handleNodeEvent(nEvent *NodeEvent) bool {
 }
 
 func (nDB *NetworkDB) handleNetworkEvent(nEvent *NetworkEvent) bool {
+	var flushEntries bool
 	// Update our local clock if the received messages has newer
 	// time.
 	nDB.networkClock.Witness(nEvent.LTime)
 
 	nDB.Lock()
-	defer nDB.Unlock()
+	defer func() {
+		nDB.Unlock()
+		// When a node leaves a network on the last task removal cleanup the
+		// local entries for this network & node combination. When the tasks
+		// on a network are removed we could have missed the gossip updates.
+		// Not doing this cleanup can leave stale entries because bulksyncs
+		// from the node will no longer include this network state.
+		//
+		// deleteNodeNetworkEntries takes nDB lock.
+		if flushEntries {
+			nDB.deleteNodeNetworkEntries(nEvent.NetworkID, nEvent.NodeName)
+		}
+	}()
 
 	if nEvent.NodeName == nDB.config.NodeName {
 		return false
@@ -121,6 +134,7 @@ func (nDB *NetworkDB) handleNetworkEvent(nEvent *NetworkEvent) bool {
 		n.leaving = nEvent.Type == NetworkEventTypeLeave
 		if n.leaving {
 			n.reapTime = reapInterval
+			flushEntries = true
 		}
 
 		nDB.addNetworkNode(nEvent.NetworkID, nEvent.NodeName)

vendor/github.com/docker/libnetwork/networkdb/networkdb.go

@@ -372,6 +372,37 @@ func (nDB *NetworkDB) deleteNetworkEntriesForNode(deletedNode string) {
 	nDB.Unlock()
 }
 
+func (nDB *NetworkDB) deleteNodeNetworkEntries(nid, node string) {
+	nDB.Lock()
+	nDB.indexes[byNetwork].WalkPrefix(fmt.Sprintf("/%s", nid),
+		func(path string, v interface{}) bool {
+			oldEntry := v.(*entry)
+			params := strings.Split(path[1:], "/")
+			nid := params[0]
+			tname := params[1]
+			key := params[2]
+
+			if oldEntry.node != node {
+				return false
+			}
+
+			entry := &entry{
+				ltime:    oldEntry.ltime,
+				node:     node,
+				value:    oldEntry.value,
+				deleting: true,
+				reapTime: reapInterval,
+			}
+
+			nDB.indexes[byTable].Insert(fmt.Sprintf("/%s/%s/%s", tname, nid, key), entry)
+			nDB.indexes[byNetwork].Insert(fmt.Sprintf("/%s/%s/%s", nid, tname, key), entry)
+
+			nDB.broadcaster.Write(makeEvent(opDelete, tname, nid, key, entry.value))
+			return false
+		})
+	nDB.Unlock()
+}
+
 func (nDB *NetworkDB) deleteNodeTableEntries(node string) {
 	nDB.Lock()
 	nDB.indexes[byTable].Walk(func(path string, v interface{}) bool {

vendor/github.com/docker/libnetwork/ns/init_linux.go

@@ -75,13 +75,28 @@ func NlHandle() *netlink.Handle {
 
 func getSupportedNlFamilies() []int {
 	fams := []int{syscall.NETLINK_ROUTE}
+	// NETLINK_XFRM test
 	if err := loadXfrmModules(); err != nil {
 		if checkXfrmSocket() != nil {
 			logrus.Warnf("Could not load necessary modules for IPSEC rules: %v", err)
-			return fams
+		} else {
+			fams = append(fams, syscall.NETLINK_XFRM)
 		}
+	} else {
+		fams = append(fams, syscall.NETLINK_XFRM)
 	}
-	return append(fams, syscall.NETLINK_XFRM)
+	// NETLINK_NETFILTER test
+	if err := loadNfConntrackModules(); err != nil {
+		if checkNfSocket() != nil {
+			logrus.Warnf("Could not load necessary modules for Conntrack: %v", err)
+		} else {
+			fams = append(fams, syscall.NETLINK_NETFILTER)
+		}
+	} else {
+		fams = append(fams, syscall.NETLINK_NETFILTER)
+	}
+
+	return fams
 }
 
 func loadXfrmModules() error {
@@ -103,3 +118,23 @@ func checkXfrmSocket() error {
 	syscall.Close(fd)
 	return nil
 }
+
+func loadNfConntrackModules() error {
+	if out, err := exec.Command("modprobe", "-va", "nf_conntrack").CombinedOutput(); err != nil {
+		return fmt.Errorf("Running modprobe nf_conntrack failed with message: `%s`, error: %v", strings.TrimSpace(string(out)), err)
+	}
+	if out, err := exec.Command("modprobe", "-va", "nf_conntrack_netlink").CombinedOutput(); err != nil {
+		return fmt.Errorf("Running modprobe nf_conntrack_netlink failed with message: `%s`, error: %v", strings.TrimSpace(string(out)), err)
+	}
+	return nil
+}
+
+// API check on required nf_conntrack* modules (nf_conntrack, nf_conntrack_netlink)
+func checkNfSocket() error {
+	fd, err := syscall.Socket(syscall.AF_NETLINK, syscall.SOCK_RAW, syscall.NETLINK_NETFILTER)
+	if err != nil {
+		return err
+	}
+	syscall.Close(fd)
+	return nil
+}

vendor/github.com/docker/libnetwork/sandbox.go

@@ -644,13 +644,6 @@ func (sb *sandbox) SetKey(basePath string) error {
 	sb.Lock()
 	sb.osSbox = osSbox
 	sb.Unlock()
-	defer func() {
-		if err != nil {
-			sb.Lock()
-			sb.osSbox = nil
-			sb.Unlock()
-		}
-	}()
 
 	// If the resolver was setup before stop it and set it up in the
 	// new osl sandbox.