Set default IPsec authentication mode (#3849)

* Set default IPsec authentication mode to avoid Agent crash on
Windows caused by config missing.
* Add `IPsecCertAuth` to unsupported feature gate on Windows.

Fixes: #3848

Signed-off-by: Xu Liu <xliu2@vmware.com>

cmd/antrea-agent/options.go

@@ -126,7 +126,7 @@ func (o *Options) validate(args []string) error {
 	}
 	ok, ipsecAuthMode := config.GetIPsecAuthenticationModeFromStr(o.config.IPsec.AuthenticationMode)
 	if !ok {
-		return fmt.Errorf("IPsec AuthenticationMode %s is unknown", o.config.TrafficEncapMode)
+		return fmt.Errorf("IPsec AuthenticationMode %s is unknown", o.config.IPsec.AuthenticationMode)
 	}
 	if ipsecAuthMode == config.IPsecAuthenticationModeCert && !features.DefaultFeatureGate.Enabled(features.IPsecCertAuth) {
 		return fmt.Errorf("IPsec AuthenticationMode %s requires feature gate %s to be enabled", o.config.TrafficEncapMode, features.IPsecCertAuth)
@@ -257,6 +257,9 @@ func (o *Options) setDefaults() {
 	if o.config.WireGuard.Port == 0 {
 		o.config.WireGuard.Port = apis.WireGuardListenPort
 	}
+	if o.config.IPsec.AuthenticationMode == "" {
+		o.config.IPsec.AuthenticationMode = config.IPsecAuthenticationModePSK.String()
+	}
 
 	if features.DefaultFeatureGate.Enabled(features.FlowExporter) {
 		if o.config.FlowCollectorAddr == "" {

pkg/features/antrea_features.go

@@ -146,6 +146,7 @@ var (
 		Multicast:         {},
 		SecondaryNetwork:  {},
 		ServiceExternalIP: {},
+		IPsecCertAuth:     {},
 	}
 )