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fix(dhcp): can not renew an ip address

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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 <lisongmin@protonmail.com>
This commit is contained in:
Songmin Li
2024-09-14 22:00:20 +08:00
committed by Casey Callendrello
parent e4950728ce
commit d61e7e5e1f
310 changed files with 12785 additions and 11182 deletions
Download Patch File Download Diff File Expand all files Collapse all files

75
plugins/ipam/dhcp/dhcp_test.go
View File

@ -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)
}
}
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),
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())),
)
if err != nil {
return nil, fmt.Errorf("failed to create DHCP server: %v", err)
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
}
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")