Merge pull request #5552 from sjoerdsimons/sjoerd/flannel-wireguard-mode

go.mod

@@ -75,7 +75,7 @@ require (
 	github.com/coreos/go-systemd v0.0.0-20190719114852-fd7a80b32e1f
 	github.com/docker/docker v20.10.14+incompatible
 	github.com/erikdubbelboer/gspt v0.0.0-20190125194910-e68493906b83
-	github.com/flannel-io/flannel v0.17.0
+	github.com/flannel-io/flannel v0.18.1
 	github.com/go-bindata/go-bindata v3.1.2+incompatible
 	github.com/go-sql-driver/mysql v1.6.0
 	github.com/golangplus/testing v1.0.0 // indirect
@@ -109,7 +109,7 @@ require (
 	github.com/stretchr/testify v1.7.0
 	github.com/tchap/go-patricia v2.3.0+incompatible // indirect
 	github.com/urfave/cli v1.22.4
-	github.com/vishvananda/netlink v1.1.1-0.20210330154013-f5de75959ad5
+	github.com/vishvananda/netlink v1.2.1-beta.2
 	github.com/yl2chen/cidranger v1.0.2
 	go.etcd.io/etcd/api/v3 v3.5.4
 	go.etcd.io/etcd/client/pkg/v3 v3.5.4

pkg/agent/flannel/setup.go

@@ -81,7 +81,8 @@ const (
 
 	wireguardNativeBackend = `{
 	"Type": "wireguard",
-	"PersistentKeepaliveInterval": 25
+	"PersistentKeepaliveInterval": %PersistentKeepaliveInterval%,
+	"Mode": "%Mode%"
 }`
 
 	emptyIPv6Network = "::/0"
@@ -206,8 +207,22 @@ func createFlannelConf(nodeConfig *config.Node) error {
 	}
 
 	var backendConf string
+	parts := strings.SplitN(nodeConfig.FlannelBackend, "=", 2)
+	backend := parts[0]
+	backendOptions := make(map[string]string)
+	if len(parts) > 1 {
+		options := strings.Split(parts[1], ",")
+		for _, o := range options {
+			p := strings.SplitN(o, "=", 2)
+			if len(p) == 1 {
+				backendOptions[p[0]] = ""
+			} else {
+				backendOptions[p[0]] = p[1]
+			}
+		}
+	}
 
-	switch nodeConfig.FlannelBackend {
+	switch backend {
 	case config.FlannelBackendVXLAN:
 		backendConf = vxlanBackend
 	case config.FlannelBackendHostGW:
@@ -221,7 +236,16 @@ func createFlannelConf(nodeConfig *config.Node) error {
 		backendConf = strings.ReplaceAll(wireguardBackend, "%flannelConfDir%", filepath.Dir(nodeConfig.FlannelConfFile))
 		logrus.Warnf("The wireguard backend is deprecated and will be removed in k3s v1.26, please switch to wireguard-native. Check our docs for information about how to migrate")
 	case config.FlannelBackendWireguardNative:
-		backendConf = wireguardNativeBackend
+		mode, ok := backendOptions["Mode"]
+		if !ok {
+			mode = "separate"
+		}
+		keepalive, ok := backendOptions["PersistentKeepaliveInterval"]
+		if !ok {
+			keepalive = "25"
+		}
+		backendConf = strings.ReplaceAll(wireguardNativeBackend, "%Mode%", mode)
+		backendConf = strings.ReplaceAll(backendConf, "%PersistentKeepaliveInterval%", keepalive)
 	default:
 		return fmt.Errorf("Cannot configure unknown flannel backend '%s'", nodeConfig.FlannelBackend)
 	}

pkg/cli/cmds/server.go

@@ -207,7 +207,7 @@ var ServerFlags = []cli.Flag{
 	ClusterDomain,
 	cli.StringFlag{
 		Name:        "flannel-backend",
-		Usage:       "(networking) One of 'none', 'vxlan', 'ipsec', 'host-gw', 'wireguard'(deprecated), or 'wireguard-native'",
+		Usage:       "(networking) backend<=option1=val1,option2=val2> where backend is one of 'none', 'vxlan', 'ipsec', 'host-gw', 'wireguard-native', or 'wireguard' (deprecated)",
 		Destination: &ServerConfig.FlannelBackend,
 		Value:       "vxlan",
 	},