DHCP timeout is configurable

plugins/ipam/dhcp/daemon.go

@@ -26,6 +26,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"sync"
+	"time"
 
 	"github.com/containernetworking/cni/pkg/skel"
 	"github.com/containernetworking/cni/pkg/types"
@@ -41,11 +42,13 @@ type DHCP struct {
 	mux             sync.Mutex
 	leases          map[string]*DHCPLease
 	hostNetnsPrefix string
+	clientTimeout   time.Duration
 }
 
-func newDHCP() *DHCP {
+func newDHCP(clientTimeout time.Duration) *DHCP {
 	return &DHCP{
-		leases: make(map[string]*DHCPLease),
+		leases:        make(map[string]*DHCPLease),
+		clientTimeout: clientTimeout,
 	}
 }
 
@@ -63,7 +66,7 @@ func (d *DHCP) Allocate(args *skel.CmdArgs, result *current.Result) error {
 
 	clientID := generateClientID(args.ContainerID, conf.Name, args.IfName)
 	hostNetns := d.hostNetnsPrefix + args.Netns
-	l, err := AcquireLease(clientID, hostNetns, args.IfName)
+	l, err := AcquireLease(clientID, hostNetns, args.IfName, d.clientTimeout)
 	if err != nil {
 		return err
 	}
@@ -156,7 +159,10 @@ func getListener(socketPath string) (net.Listener, error) {
 	}
 }
 
-func runDaemon(pidfilePath string, hostPrefix string, socketPath string) error {
+func runDaemon(
+	pidfilePath, hostPrefix, socketPath string,
+	dhcpClientTimeout time.Duration,
+) error {
 	// since other goroutines (on separate threads) will change namespaces,
 	// ensure the RPC server does not get scheduled onto those
 	runtime.LockOSThread()
@@ -176,7 +182,7 @@ func runDaemon(pidfilePath string, hostPrefix string, socketPath string) error {
 		return fmt.Errorf("Error getting listener: %v", err)
 	}
 
-	dhcp := newDHCP()
+	dhcp := newDHCP(dhcpClientTimeout)
 	dhcp.hostNetnsPrefix = hostPrefix
 	rpc.Register(dhcp)
 	rpc.HandleHTTP()

plugins/ipam/dhcp/lease.go

@@ -56,6 +56,7 @@ type DHCPLease struct {
 	renewalTime   time.Time
 	rebindingTime time.Time
 	expireTime    time.Time
+	timeout       time.Duration
 	stopping      uint32
 	stop          chan struct{}
 	wg            sync.WaitGroup
@@ -64,11 +65,15 @@ type DHCPLease struct {
 // AcquireLease gets an DHCP lease and then maintains it in the background
 // by periodically renewing it. The acquired lease can be released by
 // calling DHCPLease.Stop()
-func AcquireLease(clientID, netns, ifName string) (*DHCPLease, error) {
+func AcquireLease(
+	clientID, netns, ifName string,
+	timeout time.Duration,
+) (*DHCPLease, error) {
 	errCh := make(chan error, 1)
 	l := &DHCPLease{
 		clientID: clientID,
 		stop:     make(chan struct{}),
+		timeout:  timeout,
 	}
 
 	log.Printf("%v: acquiring lease", clientID)
@@ -115,7 +120,7 @@ func (l *DHCPLease) Stop() {
 }
 
 func (l *DHCPLease) acquire() error {
-	c, err := newDHCPClient(l.link, l.clientID)
+	c, err := newDHCPClient(l.link, l.clientID, l.timeout)
 	if err != nil {
 		return err
 	}
@@ -242,7 +247,7 @@ func (l *DHCPLease) downIface() {
 }
 
 func (l *DHCPLease) renew() error {
-	c, err := newDHCPClient(l.link, l.clientID)
+	c, err := newDHCPClient(l.link, l.clientID, l.timeout)
 	if err != nil {
 		return err
 	}
@@ -273,7 +278,7 @@ func (l *DHCPLease) renew() error {
 func (l *DHCPLease) release() error {
 	log.Printf("%v: releasing lease", l.clientID)
 
-	c, err := newDHCPClient(l.link, l.clientID)
+	c, err := newDHCPClient(l.link, l.clientID, l.timeout)
 	if err != nil {
 		return err
 	}
@@ -361,15 +366,18 @@ func backoffRetry(f func() (*dhcp4.Packet, error)) (*dhcp4.Packet, error) {
 	return nil, errNoMoreTries
 }
 
-func newDHCPClient(link netlink.Link, clientID string) (*dhcp4client.Client, error) {
+func newDHCPClient(
+	link netlink.Link, clientID string,
+	timeout time.Duration,
+) (*dhcp4client.Client, error) {
 	pktsock, err := dhcp4client.NewPacketSock(link.Attrs().Index)
 	if err != nil {
 		return nil, err
 	}
 
 	return dhcp4client.New(
 		dhcp4client.HardwareAddr(link.Attrs().HardwareAddr),
-		dhcp4client.Timeout(5*time.Second),
+		dhcp4client.Timeout(timeout),
 		dhcp4client.Broadcast(false),
 		dhcp4client.Connection(pktsock),
 	)

plugins/ipam/dhcp/main.go

@@ -22,6 +22,7 @@ import (
 	"net/rpc"
 	"os"
 	"path/filepath"
+	"time"
 
 	"github.com/containernetworking/cni/pkg/skel"
 	"github.com/containernetworking/cni/pkg/types"
@@ -37,17 +38,19 @@ func main() {
 		var pidfilePath string
 		var hostPrefix string
 		var socketPath string
+		var timeout time.Duration
 		daemonFlags := flag.NewFlagSet("daemon", flag.ExitOnError)
 		daemonFlags.StringVar(&pidfilePath, "pidfile", "", "optional path to write daemon PID to")
 		daemonFlags.StringVar(&hostPrefix, "hostprefix", "", "optional prefix to host root")
 		daemonFlags.StringVar(&socketPath, "socketpath", "", "optional dhcp server socketpath")
+		daemonFlags.DurationVar(&timeout, "timeout", 10*time.Second, "optional dhcp client timeout duration")
 		daemonFlags.Parse(os.Args[2:])
 
 		if socketPath == "" {
 			socketPath = defaultSocketPath
 		}
 
-		if err := runDaemon(pidfilePath, hostPrefix, socketPath); err != nil {
+		if err := runDaemon(pidfilePath, hostPrefix, socketPath, timeout); err != nil {
 			log.Printf(err.Error())
 			os.Exit(1)
 		}