Add keepalive to wesher

(cherry picked from commit 982cac3b1a69d5759eaf477785301a564b551bc5)

README.md

@@ -145,6 +145,7 @@ All options can be passed either as command-line flags or environment variables:
 | `--interface DEV` | WESHER_INTERFACE | name of the wireguard interface to create and manage | `wgoverlay` |
 | `--no-etc-hosts` | WESHER_NO_ETC_HOSTS | whether to skip writing hosts entries for each node in mesh | `false` |
 | `--log-level LEVEL` | WESHER_LOG_LEVEL | set the verbosity (one of debug/info/warn/error) | `warn` |
+| `--keepalive-interval INTERVAL` | WESHER_KEEPALIVE_INTERVAL | interval for which to send keepalive packets | `30s` |
 
 ## Running multiple clusters
 

config.go

@@ -26,6 +26,7 @@ type config struct {
 	NoEtcHosts        bool     `id:"no-etc-hosts" desc:"disable writing of entries to /etc/hosts"`
 	LogLevel          string   `id:"log-level" desc:"set the verbosity (debug/info/warn/error)" default:"warn"`
 	Version           bool     `desc:"display current version and exit"`
+	KeepaliveInterval string   `id:"keepalive-interval" desc:"interval for which to send keepalive packets" default:"30s"`
 
 	// for easier local testing; will break etchosts entry
 	UseIPAsName bool `id:"ip-as-name" default:"false" opts:"hidden"`

main.go

@@ -39,7 +39,13 @@ func main() {
 	if err != nil {
 		logrus.WithError(err).Fatal("could not create cluster")
 	}
-	wgstate, localNode, err := wg.New(config.Interface, config.WireguardPort, config.BaseMtu, (*net.IPNet)(config.OverlayNet), cluster.LocalName)
+
+	keepaliveDuration, err := time.ParseDuration(config.KeepaliveInterval)
+	if err != nil {
+		logrus.WithError(err).Fatal("could not parse time duration for keepalive")
+	}
+
+	wgstate, localNode, err := wg.New(config.Interface, config.WireguardPort, config.BaseMtu, (*net.IPNet)(config.OverlayNet), cluster.LocalName, &keepaliveDuration)
 	if err != nil {
 		logrus.WithError(err).Fatal("could not instantiate wireguard controller")
 	}

wg/wireguard.go

@@ -4,6 +4,7 @@ import (
 	"hash/fnv"
 	"net"
 	"os"
+	"time"
 
 	"github.com/costela/wesher/common"
 	"github.com/pkg/errors"
@@ -21,12 +22,13 @@ type State struct {
 	Mtu               int
 	PrivKey           wgtypes.Key
 	PubKey            wgtypes.Key
+	KeepaliveInterval *time.Duration
 }
 
 // New creates a new Wesher Wireguard state
 // The Wireguard keys are generated for every new interface
 // The interface must later be setup using SetUpInterface
-func New(iface string, port int, mtu int, ipnet *net.IPNet, name string) (*State, *common.Node, error) {
+func New(iface string, port int, mtu int, ipnet *net.IPNet, name string, keepaliveInterval *time.Duration) (*State, *common.Node, error) {
 	client, err := wgctrl.New()
 	if err != nil {
 		return nil, nil, errors.Wrap(err, "could not instantiate wireguard client")
@@ -45,6 +47,7 @@ func New(iface string, port int, mtu int, ipnet *net.IPNet, name string) (*State
 		Mtu:               mtu,
 		PrivKey:           privKey,
 		PubKey:            pubKey,
+		KeepaliveInterval: keepaliveInterval,
 	}
 	state.assignOverlayAddr(ipnet, name)
 
@@ -193,6 +196,7 @@ func (s *State) nodesToPeerConfigs(nodes []common.Node) ([]wgtypes.PeerConfig, e
 				Port: s.Port,
 			},
 			AllowedIPs:                  append([]net.IPNet{node.OverlayAddr}, node.Routes...),
+			PersistentKeepaliveInterval: s.KeepaliveInterval,
 		}
 	}
 	return peerCfgs, nil