feat: Implement BFD for BGPPeers

Signed-off-by: Sven Rosenzweig <sven.rosenzweig@sap.com>

Author: sven-rosenzweig

api/core/v1alpha1/bfd_types.go

@@ -0,0 +1,41 @@
+// SPDX-FileCopyrightText: 2026 SAP SE or an SAP affiliate company and IronCore contributors
+// SPDX-License-Identifier: Apache-2.0
+
+package v1alpha1
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// BFD defines the Bidirectional Forwarding Detection configuration for interfaces, bgp peerings and static routes.
+type BFD struct {
+	// Enabled indicates whether BFD is enabled on the network object.
+	// +required
+	Enabled bool `json:"enabled"`
+
+	// DesiredMinimumTxInterval is the minimum interval between transmission of BFD control
+	// packets that the operator desires. This value is advertised to the peer.
+	// The actual interval used is the maximum of this value and the remote
+	// required-minimum-receive interval value.
+	// +optional
+	// +kubebuilder:validation:Type=string
+	// +kubebuilder:validation:Pattern="^([0-9]+(\\.[0-9]+)?(ns|us|µs|ms|s|m|h))+$"
+	DesiredMinimumTxInterval *metav1.Duration `json:"desiredMinimumTxInterval,omitempty"`
+
+	// RequiredMinimumReceive is the minimum interval between received BFD control packets
+	// that this system should support. This value is advertised to the remote peer to
+	// indicate the maximum frequency between BFD control packets that is acceptable
+	// to the local system.
+	// +optional
+	// +kubebuilder:validation:Type=string
+	// +kubebuilder:validation:Pattern="^([0-9]+(\\.[0-9]+)?(ns|us|µs|ms|s|m|h))+$"
+	RequiredMinimumReceive *metav1.Duration `json:"requiredMinimumReceive,omitempty"`
+
+	// DetectionMultiplier is the number of packets that must be missed to declare
+	// this session as down. The detection interval for the BFD session is calculated
+	// by multiplying the value of the negotiated transmission interval by this value.
+	// +optional
+	// +kubebuilder:validation:Minimum=1
+	// +kubebuilder:validation:Maximum=255
+	DetectionMultiplier *int32 `json:"detectionMultiplier,omitempty"`
+}

api/core/v1alpha1/bgp_peer_types.go

@@ -64,6 +64,11 @@ type BGPPeerSpec struct {
 	// LocalAS configures the local AS number and how it factors into BGP announcements for this peer.
 	// +optional
 	LocalAS *LocalAS `json:"localAS,omitempty"`
+
+	// BFD defines the Bidirectional Forwarding Detection configuration for the interface.
+	// BFD is only applicable for Layer 3 interfaces.
+	// +optional
+	BFD *BFD `json:"bfd,omitempty"`
 }
 
 // LocalAS defines the local AS configuration and how it factors in BGP announcements.

api/core/v1alpha1/interface_types.go

@@ -266,39 +266,6 @@ type InterfaceIPv4Unnumbered struct {
 	InterfaceRef LocalObjectReference `json:"interfaceRef"`
 }
 
-// BFD defines the Bidirectional Forwarding Detection configuration for an interface.
-type BFD struct {
-	// Enabled indicates whether BFD is enabled on the interface.
-	// +required
-	Enabled bool `json:"enabled"`
-
-	// DesiredMinimumTxInterval is the minimum interval between transmission of BFD control
-	// packets that the operator desires. This value is advertised to the peer.
-	// The actual interval used is the maximum of this value and the remote
-	// required-minimum-receive interval value.
-	// +optional
-	// +kubebuilder:validation:Type=string
-	// +kubebuilder:validation:Pattern="^([0-9]+(\\.[0-9]+)?(ns|us|µs|ms|s|m|h))+$"
-	DesiredMinimumTxInterval *metav1.Duration `json:"desiredMinimumTxInterval,omitempty"`
-
-	// RequiredMinimumReceive is the minimum interval between received BFD control packets
-	// that this system should support. This value is advertised to the remote peer to
-	// indicate the maximum frequency between BFD control packets that is acceptable
-	// to the local system.
-	// +optional
-	// +kubebuilder:validation:Type=string
-	// +kubebuilder:validation:Pattern="^([0-9]+(\\.[0-9]+)?(ns|us|µs|ms|s|m|h))+$"
-	RequiredMinimumReceive *metav1.Duration `json:"requiredMinimumReceive,omitempty"`
-
-	// DetectionMultiplier is the number of packets that must be missed to declare
-	// this session as down. The detection interval for the BFD session is calculated
-	// by multiplying the value of the negotiated transmission interval by this value.
-	// +optional
-	// +kubebuilder:validation:Minimum=1
-	// +kubebuilder:validation:Maximum=255
-	DetectionMultiplier *int32 `json:"detectionMultiplier,omitempty"`
-}
-
 // Ethernet defines the ethernet-specific configuration for physical interfaces.
 type Ethernet struct {
 	// FECMode specifies the Forward Error Correction mode for the interface.

api/core/v1alpha1/zz_generated.deepcopy.go

@@ -71,6 +71,12 @@ type BGPPeer struct {
 	Name      string                   `json:"vrf-name"`
 	RD        RouteDistinguisher       `json:"rd,omitzero"`
 	Neighbors NeighborList             `json:"neighbors,omitzero"`
+	BFD       *BFD                     `json:"bfd,omitzero"`
+}
+
+type BFD struct {
+	MinInterval uint32 `json:"minimum-interval,omitempty"`
+	Multiplier  uint32 `json:"multiplier,omitempty"`
 }
 
 // ActivatedAddressFamilies is required for IOS XR to activate the Address-Family under the BGP process