fix(dhcp): can not renew an ip address

The dhcp server is systemd-networkd, and the dhcp
plugin can request an ip but can not renew it.
The systemd-networkd just ignore the renew request.

```
2024/09/14 21:46:00 no DHCP packet received within 10s
2024/09/14 21:46:00 retrying in 31.529038 seconds
2024/09/14 21:46:42 no DHCP packet received within 10s
2024/09/14 21:46:42 retrying in 63.150490 seconds
2024/09/14 21:47:45 98184616c91f15419f5cacd012697f85afaa2daeb5d3233e28b0ec21589fb45a/iot/eth1: no more tries
2024/09/14 21:47:45 98184616c91f15419f5cacd012697f85afaa2daeb5d3233e28b0ec21589fb45a/iot/eth1: renewal time expired, rebinding
2024/09/14 21:47:45 Link "eth1" down. Attempting to set up
2024/09/14 21:47:45 98184616c91f15419f5cacd012697f85afaa2daeb5d3233e28b0ec21589fb45a/iot/eth1: lease rebound, expiration is 2024-09-14 22:47:45.309270751 +0800 CST m=+11730.048516519
```

Follow the https://datatracker.ietf.org/doc/html/rfc2131#section-4.3.6,
following options must not be sent in renew

- Requested IP Address
- Server Identifier

Since the upstream code has been inactive for 6 years,
we should switch to another dhcpv4 library.
The new selected one is https://github.com/insomniacslk/dhcp.

Signed-off-by: Songmin Li <[email protected]>

.github/workflows/test.yaml

@@ -67,6 +67,10 @@ jobs:
           sudo apt-get install linux-modules-extra-$(uname -r)
       - name: Install nftables
         run: sudo apt-get install nftables
+      - name: Install dnsmasq(dhcp server)
+        run: |
+          sudo apt-get install dnsmasq
+          sudo systemctl disable --now dnsmasq
       - uses: actions/checkout@v4
       - name: setup go
         uses: actions/setup-go@v5

go.mod

@@ -9,10 +9,8 @@ require (
 	github.com/containernetworking/cni v1.2.3
 	github.com/coreos/go-iptables v0.8.0
 	github.com/coreos/go-systemd/v22 v22.5.0
-	github.com/d2g/dhcp4 v0.0.0-20170904100407-a1d1b6c41b1c
-	github.com/d2g/dhcp4client v1.0.0
-	github.com/d2g/dhcp4server v0.0.0-20181031114812-7d4a0a7f59a5
 	github.com/godbus/dbus/v5 v5.1.0
+	github.com/insomniacslk/dhcp v0.0.0-20240829085014-a3a4c1f04475
 	github.com/mattn/go-shellwords v1.0.12
 	github.com/networkplumbing/go-nft v0.4.0
 	github.com/onsi/ginkgo/v2 v2.20.2
@@ -28,17 +26,22 @@ require (
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/containerd/cgroups/v3 v3.0.3 // indirect
 	github.com/containerd/errdefs v0.1.0 // indirect
-	github.com/d2g/hardwareaddr v0.0.0-20190221164911-e7d9fbe030e4 // indirect
 	github.com/go-logr/logr v1.4.2 // indirect
 	github.com/go-task/slim-sprig/v3 v3.0.0 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/google/go-cmp v0.6.0 // indirect
 	github.com/google/pprof v0.0.0-20240827171923-fa2c70bbbfe5 // indirect
+	github.com/josharian/native v1.1.0 // indirect
+	github.com/mdlayher/packet v1.1.2 // indirect
+	github.com/mdlayher/socket v0.5.1 // indirect
+	github.com/pierrec/lz4/v4 v4.1.21 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
+	github.com/u-root/uio v0.0.0-20240224005618-d2acac8f3701 // indirect
 	github.com/vishvananda/netns v0.0.4 // indirect
 	go.opencensus.io v0.24.0 // indirect
 	golang.org/x/net v0.28.0 // indirect
+	golang.org/x/sync v0.8.0 // indirect
 	golang.org/x/text v0.17.0 // indirect
 	golang.org/x/tools v0.24.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20240701130421-f6361c86f094 // indirect

go.sum

@@ -21,14 +21,6 @@ github.com/coreos/go-iptables v0.8.0 h1:MPc2P89IhuVpLI7ETL/2tx3XZ61VeICZjYqDEgNs
 github.com/coreos/go-iptables v0.8.0/go.mod h1:Qe8Bv2Xik5FyTXwgIbLAnv2sWSBmvWdFETJConOQ//Q=
 github.com/coreos/go-systemd/v22 v22.5.0 h1:RrqgGjYQKalulkV8NGVIfkXQf6YYmOyiJKk8iXXhfZs=
 github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
-github.com/d2g/dhcp4 v0.0.0-20170904100407-a1d1b6c41b1c h1:Xo2rK1pzOm0jO6abTPIQwbAmqBIOj132otexc1mmzFc=
-github.com/d2g/dhcp4 v0.0.0-20170904100407-a1d1b6c41b1c/go.mod h1:Ct2BUK8SB0YC1SMSibvLzxjeJLnrYEVLULFNiHY9YfQ=
-github.com/d2g/dhcp4client v1.0.0 h1:suYBsYZIkSlUMEz4TAYCczKf62IA2UWC+O8+KtdOhCo=
-github.com/d2g/dhcp4client v1.0.0/go.mod h1:j0hNfjhrt2SxUOw55nL0ATM/z4Yt3t2Kd1mW34z5W5s=
-github.com/d2g/dhcp4server v0.0.0-20181031114812-7d4a0a7f59a5 h1:+CpLbZIeUn94m02LdEKPcgErLJ347NUwxPKs5u8ieiY=
-github.com/d2g/dhcp4server v0.0.0-20181031114812-7d4a0a7f59a5/go.mod h1:Eo87+Kg/IX2hfWJfwxMzLyuSZyxSoAug2nGa1G2QAi8=
-github.com/d2g/hardwareaddr v0.0.0-20190221164911-e7d9fbe030e4 h1:itqmmf1PFpC4n5JW+j4BU7X4MTfVurhYRTjODoPb2Y8=
-github.com/d2g/hardwareaddr v0.0.0-20190221164911-e7d9fbe030e4/go.mod h1:bMl4RjIciD2oAxI7DmWRx6gbeqrkoLqv3MV0vzNad+I=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -68,10 +60,20 @@ github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeN
 github.com/google/pprof v0.0.0-20240827171923-fa2c70bbbfe5 h1:5iH8iuqE5apketRbSFBy+X1V0o+l+8NF1avt4HWl7cA=
 github.com/google/pprof v0.0.0-20240827171923-fa2c70bbbfe5/go.mod h1:vavhavw2zAxS5dIdcRluK6cSGGPlZynqzFM8NdvU144=
 github.com/google/uuid v1.1.2/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/hugelgupf/socketpair v0.0.0-20190730060125-05d35a94e714 h1:/jC7qQFrv8CrSJVmaolDVOxTfS9kc36uB6H40kdbQq8=
+github.com/hugelgupf/socketpair v0.0.0-20190730060125-05d35a94e714/go.mod h1:2Goc3h8EklBH5mspfHFxBnEoURQCGzQQH1ga9Myjvis=
+github.com/insomniacslk/dhcp v0.0.0-20240829085014-a3a4c1f04475 h1:hxST5pwMBEOWmxpkX20w9oZG+hXdhKmAIPQ3NGGAxas=
+github.com/insomniacslk/dhcp v0.0.0-20240829085014-a3a4c1f04475/go.mod h1:KclMyHxX06VrVr0DJmeFSUb1ankt7xTfoOA35pCkoic=
+github.com/josharian/native v1.1.0 h1:uuaP0hAbW7Y4l0ZRQ6C9zfb7Mg1mbFKry/xzDAfmtLA=
+github.com/josharian/native v1.1.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
 github.com/lithammer/dedent v1.1.0 h1:VNzHMVCBNG1j0fh3OrsFRkVUwStdDArbgBWoPAffktY=
 github.com/lithammer/dedent v1.1.0/go.mod h1:jrXYCQtgg0nJiN+StA2KgR7w6CiQNv9Fd/Z9BP0jIOc=
 github.com/mattn/go-shellwords v1.0.12 h1:M2zGm7EW6UQJvDeQxo4T51eKPurbeFbe8WtebGE2xrk=
 github.com/mattn/go-shellwords v1.0.12/go.mod h1:EZzvwXDESEeg03EKmM+RmDnNOPKG4lLtQsUlTZDWQ8Y=
+github.com/mdlayher/packet v1.1.2 h1:3Up1NG6LZrsgDVn6X4L9Ge/iyRyxFEFD9o6Pr3Q1nQY=
+github.com/mdlayher/packet v1.1.2/go.mod h1:GEu1+n9sG5VtiRE4SydOmX5GTwyyYlteZiFU+x0kew4=
+github.com/mdlayher/socket v0.5.1 h1:VZaqt6RkGkt2OE9l3GcC6nZkqD3xKeQLyfleW/uBcos=
+github.com/mdlayher/socket v0.5.1/go.mod h1:TjPLHI1UgwEv5J1B5q0zTZq12A/6H7nKmtTanQE37IQ=
 github.com/networkplumbing/go-nft v0.4.0 h1:kExVMwXW48DOAukkBwyI16h4uhE5lN9iMvQd52lpTyU=
 github.com/networkplumbing/go-nft v0.4.0/go.mod h1:HnnM+tYvlGAsMU7yoYwXEVLLiDW9gdMmb5HoGcwpuQs=
 github.com/onsi/ginkgo/v2 v2.20.2 h1:7NVCeyIWROIAheY21RLS+3j2bb52W0W82tkberYytp4=
@@ -80,6 +82,8 @@ github.com/onsi/gomega v1.34.2 h1:pNCwDkzrsv7MS9kpaQvVb1aVLahQXyJ/Tv5oAZMI3i8=
 github.com/onsi/gomega v1.34.2/go.mod h1:v1xfxRgk0KIsG+QOdm7p8UosrOzPYRo60fd3B/1Dukc=
 github.com/opencontainers/selinux v1.11.0 h1:+5Zbo97w3Lbmb3PeqQtpmTkMwsW5nRI3YaLpt7tQ7oU=
 github.com/opencontainers/selinux v1.11.0/go.mod h1:E5dMC3VPuVvVHDYmi78qvhJp8+M586T4DlDRYpFkyec=
+github.com/pierrec/lz4/v4 v4.1.21 h1:yOVMLb6qSIDP67pl/5F7RepeKYu/VmTyEXvuMI5d9mQ=
+github.com/pierrec/lz4/v4 v4.1.21/go.mod h1:gZWDp/Ze/IJXGXf23ltt2EXimqmTUXEy0GFuRQyBid4=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
 github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
@@ -99,6 +103,8 @@ github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
+github.com/u-root/uio v0.0.0-20240224005618-d2acac8f3701 h1:pyC9PaHYZFgEKFdlp3G8RaCKgVpHZnecvArXvPXcFkM=
+github.com/u-root/uio v0.0.0-20240224005618-d2acac8f3701/go.mod h1:P3a5rG4X7tI17Nn3aOIAYr5HbIMukwXG0urG0WuL8OA=
 github.com/vishvananda/netlink v1.3.0 h1:X7l42GfcV4S6E4vHTsw48qbrV+9PVojNfIhZcwQdrZk=
 github.com/vishvananda/netlink v1.3.0/go.mod h1:i6NetklAujEcC6fK0JPjT8qSwWyO0HLn4UKG+hGqeJs=
 github.com/vishvananda/netns v0.0.4 h1:Oeaw1EM2JMxD51g9uhtC0D7erkIjgmj8+JZc26m1YX8=
@@ -129,6 +135,8 @@ golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20181108010431-42b317875d0f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.8.0 h1:3NFvSEYkUoMifnESzZl15y791HH1qU2xm6eCJU5ZPXQ=
+golang.org/x/sync v0.8.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

plugins/ipam/dhcp/daemon.go

@@ -74,7 +74,7 @@ func (d *DHCP) Allocate(args *skel.CmdArgs, result *current.Result) error {
 		return fmt.Errorf("error parsing netconf: %v", err)
 	}
 
-	optsRequesting, optsProviding, err := prepareOptions(args.Args, conf.IPAM.ProvideOptions, conf.IPAM.RequestOptions)
+	opts, err := prepareOptions(args.Args, conf.IPAM.ProvideOptions, conf.IPAM.RequestOptions)
 	if err != nil {
 		return err
 	}
@@ -89,7 +89,7 @@ func (d *DHCP) Allocate(args *skel.CmdArgs, result *current.Result) error {
 	} else {
 		hostNetns := d.hostNetnsPrefix + args.Netns
 		l, err = AcquireLease(clientID, hostNetns, args.IfName,
-			optsRequesting, optsProviding,
+			opts,
 			d.clientTimeout, d.clientResendMax, d.broadcast)
 		if err != nil {
 			return err

plugins/ipam/dhcp/dhcp2_test.go

@@ -61,8 +61,7 @@ var _ = Describe("DHCP Multiple Lease Operations", func() {
 		})
 
 		// Start the DHCP server
-		dhcpServerDone, err = dhcpServerStart(originalNS, 2, dhcpServerStopCh)
-		Expect(err).NotTo(HaveOccurred())
+		dhcpServerDone = dhcpServerStart(originalNS, 2, dhcpServerStopCh)
 
 		// Start the DHCP client daemon
 		dhcpPluginPath, err := exec.LookPath("dhcp")

plugins/ipam/dhcp/dhcp_test.go

@@ -25,10 +25,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/d2g/dhcp4"
-	"github.com/d2g/dhcp4server"
-	"github.com/d2g/dhcp4server/leasepool"
-	"github.com/d2g/dhcp4server/leasepool/memorypool"
 	. "github.com/onsi/ginkgo/v2"
 	. "github.com/onsi/gomega"
 	"github.com/vishvananda/netlink"
@@ -48,31 +44,43 @@ func getTmpDir() (string, error) {
 	return tmpDir, err
 }
 
-func dhcpServerStart(netns ns.NetNS, numLeases int, stopCh <-chan bool) (*sync.WaitGroup, error) {
-	// Add the expected IP to the pool
-	lp := memorypool.MemoryPool{}
+type DhcpServer struct {
+	cmd *exec.Cmd
 
-	Expect(numLeases).To(BeNumerically(">", 0))
-	// Currently tests only need at most 2
-	Expect(numLeases).To(BeNumerically("<=", 2))
+	startAddr net.IP
+	endAddr   net.IP
+	leaseTime time.Duration
+}
 
-	// tests expect first lease to be at address 192.168.1.5
-	for i := 5; i < numLeases+5; i++ {
-		err := lp.AddLease(leasepool.Lease{IP: dhcp4.IPAdd(net.IPv4(192, 168, 1, byte(i)), 0)})
-		if err != nil {
-			return nil, fmt.Errorf("error adding IP to DHCP pool: %v", err)
-		}
+func (s *DhcpServer) Serve() error {
+	s.cmd = exec.Command(
+		"dnsmasq",
+		"--no-daemon",
+		"--dhcp-sequential-ip", // allocate IPs sequentially
+		"--port=0",             // disable DNS
+		"--conf-file=-",        // Do not read /etc/dnsmasq.conf
+		fmt.Sprintf("--dhcp-range=%s,%s,%d", s.startAddr, s.endAddr, int(s.leaseTime.Seconds())),
+	)
+	s.cmd.Stdin = bytes.NewBufferString("")
+	s.cmd.Stdout = os.Stdout
+	s.cmd.Stderr = os.Stderr
+
+	return s.cmd.Start()
+}
+
+func (s *DhcpServer) Stop() error {
+	if err := s.cmd.Process.Kill(); err != nil {
+		return err
 	}
+	_, err := s.cmd.Process.Wait()
+	return err
+}
 
-	dhcpServer, err := dhcp4server.New(
-		net.IPv4(192, 168, 1, 1),
-		&lp,
-		dhcp4server.SetLocalAddr(net.UDPAddr{IP: net.IPv4(0, 0, 0, 0), Port: 67}),
-		dhcp4server.SetRemoteAddr(net.UDPAddr{IP: net.IPv4bcast, Port: 68}),
-		dhcp4server.LeaseDuration(time.Minute*15),
-	)
-	if err != nil {
-		return nil, fmt.Errorf("failed to create DHCP server: %v", err)
+func dhcpServerStart(netns ns.NetNS, numLeases int, stopCh <-chan bool) *sync.WaitGroup {
+	dhcpServer := &DhcpServer{
+		startAddr: net.IPv4(192, 168, 1, 5),
+		endAddr:   net.IPv4(192, 168, 1, 5+uint8(numLeases)-1),
+		leaseTime: 5 * time.Minute,
 	}
 
 	stopWg := sync.WaitGroup{}
@@ -84,9 +92,10 @@ func dhcpServerStart(netns ns.NetNS, numLeases int, stopCh <-chan bool) (*sync.W
 	go func() {
 		defer GinkgoRecover()
 
-		err = netns.Do(func(ns.NetNS) error {
+		err := netns.Do(func(ns.NetNS) error {
 			startWg.Done()
-			if err := dhcpServer.ListenAndServe(); err != nil {
+
+			if err := dhcpServer.Serve(); err != nil {
 				// Log, but don't trap errors; the server will
 				// always report an error when stopped
 				GinkgoT().Logf("DHCP server finished with error: %v", err)
@@ -103,12 +112,12 @@ func dhcpServerStart(netns ns.NetNS, numLeases int, stopCh <-chan bool) (*sync.W
 	go func() {
 		startWg.Done()
 		<-stopCh
-		dhcpServer.Shutdown()
+		dhcpServer.Stop()
 		stopWg.Done()
 	}()
 	startWg.Wait()
 
-	return &stopWg, nil
+	return &stopWg
 }
 
 const (
@@ -200,8 +209,7 @@ var _ = Describe("DHCP Operations", func() {
 		})
 
 		// Start the DHCP server
-		dhcpServerDone, err = dhcpServerStart(originalNS, 1, dhcpServerStopCh)
-		Expect(err).NotTo(HaveOccurred())
+		dhcpServerDone = dhcpServerStart(originalNS, 1, dhcpServerStopCh)
 
 		// Start the DHCP client daemon
 		dhcpPluginPath, err := exec.LookPath("dhcp")
@@ -517,8 +525,7 @@ var _ = Describe("DHCP Lease Unavailable Operations", func() {
 		})
 
 		// Start the DHCP server
-		dhcpServerDone, err = dhcpServerStart(originalNS, 1, dhcpServerStopCh)
-		Expect(err).NotTo(HaveOccurred())
+		dhcpServerDone = dhcpServerStart(originalNS, 1, dhcpServerStopCh)
 
 		// Start the DHCP client daemon
 		dhcpPluginPath, err := exec.LookPath("dhcp")