feat: Adds pfcp association request response

client/client.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"log"
 
+	"github.com/dot-5g/pfcp/headers"
 	"github.com/dot-5g/pfcp/ie"
 	"github.com/dot-5g/pfcp/messages"
 	"github.com/dot-5g/pfcp/network"
@@ -23,7 +24,7 @@ func New(ServerAddress string) *Pfcp {
 	return &Pfcp{ServerAddress: ServerAddress, Udp: udpClient}
 }
 
-func (pfcp *Pfcp) sendPfcpMessage(header messages.PFCPHeader, elements []ie.InformationElement) error {
+func (pfcp *Pfcp) sendPfcpMessage(header headers.PFCPHeader, elements []ie.InformationElement) error {
 	var payload []byte
 	for _, element := range elements {
 		payload = append(payload, element.Serialize()...)
@@ -37,14 +38,14 @@ func (pfcp *Pfcp) sendPfcpMessage(header messages.PFCPHeader, elements []ie.Info
 	return nil
 }
 
-func serializeMessage(header messages.PFCPHeader, payload []byte) []byte {
+func serializeMessage(header headers.PFCPHeader, payload []byte) []byte {
 	header.MessageLength = uint16(4 + len(payload))
-	headerBytes := messages.SerializePFCPHeader(header)
+	headerBytes := headers.SerializePFCPHeader(header)
 	return append(headerBytes, payload...)
 }
 
 func (pfcp *Pfcp) SendHeartbeatRequest(recoveryTimeStamp ie.RecoveryTimeStamp, sequenceNumber uint32) (ie.RecoveryTimeStamp, error) {
-	header := messages.NewPFCPHeader(messages.PFCPHeartbeatRequest, sequenceNumber)
+	header := headers.NewPFCPHeader(messages.PFCPHeartbeatRequest, sequenceNumber)
 	payload := []ie.InformationElement{recoveryTimeStamp}
 	err := pfcp.sendPfcpMessage(header, payload)
 	if err != nil {
@@ -54,7 +55,7 @@ func (pfcp *Pfcp) SendHeartbeatRequest(recoveryTimeStamp ie.RecoveryTimeStamp, s
 }
 
 func (pfcp *Pfcp) SendHeartbeatResponse(recoveryTimeStamp ie.RecoveryTimeStamp, sequenceNumber uint32) (ie.RecoveryTimeStamp, error) {
-	header := messages.NewPFCPHeader(messages.PFCPHeartbeatResponse, sequenceNumber)
+	header := headers.NewPFCPHeader(messages.PFCPHeartbeatResponse, sequenceNumber)
 	payload := []ie.InformationElement{recoveryTimeStamp}
 	err := pfcp.sendPfcpMessage(header, payload)
 	if err != nil {
@@ -64,11 +65,23 @@ func (pfcp *Pfcp) SendHeartbeatResponse(recoveryTimeStamp ie.RecoveryTimeStamp,
 }
 
 func (pfcp *Pfcp) SendPFCPAssociationSetupRequest(nodeID ie.NodeID, recoveryTimeStamp ie.RecoveryTimeStamp, sequenceNumber uint32) error {
-	header := messages.NewPFCPHeader(messages.PFCPAssociationSetupRequest, sequenceNumber)
+	header := headers.NewPFCPHeader(messages.PFCPAssociationSetupRequest, sequenceNumber)
 	payload := []ie.InformationElement{nodeID, recoveryTimeStamp}
 	err := pfcp.sendPfcpMessage(header, payload)
 	if err != nil {
 		return fmt.Errorf("error sending PFCP Association Setup Request: %w", err)
 	}
 	return nil
 }
+
+func (pfcp *Pfcp) SendPFCPAssociationSetupResponse(nodeID ie.NodeID, cause ie.Cause, recoveryTimeStamp ie.RecoveryTimeStamp, sequenceNumber uint32) error {
+	header := headers.NewPFCPHeader(messages.PFCPAssociationSetupResponse, sequenceNumber)
+	payload := []ie.InformationElement{nodeID, cause, recoveryTimeStamp}
+	err := pfcp.sendPfcpMessage(header, payload)
+	if err != nil {
+		return fmt.Errorf("error sending PFCP Association Setup Response: %w", err)
+	}
+	fmt.Printf("PFCP Association Setup Response sent successfully to %s.\n", pfcp.ServerAddress)
+	fmt.Printf("Payload: %v\n", payload)
+	return nil
+}

messages/header.go → headers/header.go

@@ -1,9 +1,11 @@
-package messages
+package headers
 
 import (
 	"bytes"
 	"encoding/binary"
 	"fmt"
+
+	"github.com/dot-5g/pfcp/messages"
 )
 
 type PFCPHeader struct {
@@ -13,14 +15,6 @@ type PFCPHeader struct {
 	SequenceNumber uint32
 }
 
-type PFCPMessageType int
-
-const (
-	PFCPHeartbeatRequest PFCPMessageType = iota
-	PFCPHeartbeatResponse
-	PFCPAssociationSetupRequest
-)
-
 func SerializePFCPHeader(header PFCPHeader) []byte {
 	buf := new(bytes.Buffer)
 
@@ -45,23 +39,10 @@ func SerializePFCPHeader(header PFCPHeader) []byte {
 	return buf.Bytes()
 }
 
-func messageTypeToByte(messageType PFCPMessageType) byte {
-	switch messageType {
-	case PFCPHeartbeatRequest:
-		return 1
-	case PFCPHeartbeatResponse:
-		return 2
-	case PFCPAssociationSetupRequest:
-		return 5
-	default:
-		return 0
-	}
-}
-
-func NewPFCPHeader(messageType PFCPMessageType, sequenceNumber uint32) PFCPHeader {
+func NewPFCPHeader(messageType messages.PFCPMessageType, sequenceNumber uint32) PFCPHeader {
 	return PFCPHeader{
 		Version:        1,
-		MessageType:    messageTypeToByte(messageType),
+		MessageType:    messages.MessageTypeToByte(messageType),
 		MessageLength:  0, // To be set later
 		SequenceNumber: sequenceNumber,
 	}

messages/header_test.go → headers/header_test.go

@@ -1,22 +1,22 @@
-package messages_test
+package headers_test
 
 import (
 	"bytes"
 	"encoding/binary"
 	"testing"
 
-	"github.com/dot-5g/pfcp/messages"
+	"github.com/dot-5g/pfcp/headers"
 )
 
 func TestGivenPfcpHeaderWhenSerializePFCPHeaderThenSerializedCorrectly(t *testing.T) {
-	pfcpHeader := messages.PFCPHeader{
+	pfcpHeader := headers.PFCPHeader{
 		Version:        1,
 		MessageType:    2,
 		MessageLength:  3,
 		SequenceNumber: 4,
 	}
 
-	headerBytes := messages.SerializePFCPHeader(pfcpHeader)
+	headerBytes := headers.SerializePFCPHeader(pfcpHeader)
 
 	if len(headerBytes) != 8 {
 		t.Errorf("Expected 8 bytes, got %d", len(headerBytes))

ie/cause.go

@@ -0,0 +1,43 @@
+package ie
+
+import (
+	"bytes"
+	"encoding/binary"
+)
+
+type Cause struct {
+	Type   uint16
+	Length uint16
+	Value  uint8
+}
+
+func NewCause(value int) Cause {
+	return Cause{
+		Type:   19,
+		Length: 1,
+		Value:  uint8(value),
+	}
+}
+
+func (cause Cause) Serialize() []byte {
+	buf := new(bytes.Buffer)
+
+	// Octets 1 to 2: Type
+	binary.Write(buf, binary.BigEndian, uint16(cause.Type))
+
+	// Octets 3 to 4: Length
+	binary.Write(buf, binary.BigEndian, uint16(cause.Length))
+
+	// Octet 5: Value (1 byte)
+	buf.WriteByte(cause.Value)
+
+	return buf.Bytes()
+}
+
+func DeserializeCause(ieType uint16, ieLength uint16, ieValue []byte) Cause {
+	return Cause{
+		Type:   ieType,
+		Length: ieLength,
+		Value:  ieValue[0],
+	}
+}

ie/ie.go

@@ -32,6 +32,8 @@ func ParseInformationElements(b []byte) ([]InformationElement, error) {
 		ieValue := b[index : index+int(ieLength)]
 		var ie InformationElement
 		switch ieType {
+		case 19:
+			ie = DeserializeCause(ieType, ieLength, ieValue)
 		case 60:
 			ie = DeserializeNodeID(ieType, ieLength, ieValue)
 		case 96:

ie/nodeId.go

@@ -84,8 +84,6 @@ func (n NodeID) Serialize() []byte {
 	// Octets 6 to n+5: Node ID Value
 	buf.Write(n.NodeIDValue)
 
-	fmt.Printf("Node ID - serialized: %v\n", buf.Bytes())
-
 	return buf.Bytes()
 }