From 3161bb52e0aa444fe8ff0c34466b918bb1ad8a25 Mon Sep 17 00:00:00 2001
From: toby lorne <toby@toby.codes>
Date: Mon, 11 Jan 2021 20:53:45 +0000
Subject: [PATCH] dhcp: timeout value is set in DHCP daemon

Eventually the timeout value will become a CLI argument

The default timeout was nestled all the way in the lease constructor

This commit is the first step in making the timeout configurable by
moving it to the DHCPLease constructor

Signed-off-by: toby lorne <toby@toby.codes>
---
 plugins/ipam/dhcp/daemon.go |  3 ++-
 plugins/ipam/dhcp/lease.go  | 20 ++++++++++++++------
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/plugins/ipam/dhcp/daemon.go b/plugins/ipam/dhcp/daemon.go
index 7ec2818b..a5c1e095 100644
--- a/plugins/ipam/dhcp/daemon.go
+++ b/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"
@@ -63,7 +64,7 @@ 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, 5*time.Second)
 	if err != nil {
 		return err
 	}
diff --git a/plugins/ipam/dhcp/lease.go b/plugins/ipam/dhcp/lease.go
index b014a0b6..16848fcc 100644
--- a/plugins/ipam/dhcp/lease.go
+++ b/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
 	}
@@ -361,7 +366,10 @@ 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
@@ -369,7 +377,7 @@ func newDHCPClient(link netlink.Link, clientID string) (*dhcp4client.Client, err
 
 	return dhcp4client.New(
 		dhcp4client.HardwareAddr(link.Attrs().HardwareAddr),
-		dhcp4client.Timeout(5*time.Second),
+		dhcp4client.Timeout(timeout),
 		dhcp4client.Broadcast(false),
 		dhcp4client.Connection(pktsock),
 	)