Add NBP machine (WIP)

atalk/nbp/nbp.go

@@ -35,6 +35,15 @@ const (
 	FunctionFwdReq    Function = 4
 )
 
+func (f Function) String() string {
+	return map[Function]string{
+		FunctionBrRq:      "BrRq",
+		FunctionLkUp:      "LkUp",
+		FunctionLkUpReply: "LkUp-Reply",
+		FunctionFwdReq:    "FwdReq",
+	}[f]
+}
+
 // Packet represents an NBP packet.
 type Packet struct {
 	Function Function // top 4 bits of first byte

main.go

@@ -169,6 +169,14 @@ func main() {
 	rtmpCh := make(chan *ddp.ExtPacket, 1024)
 	go rtmpMachine.Run(ctx, rtmpCh)
 
+	// --------------------- NBP --------------------
+	nbpMachine := &NBPMachine{
+		aarp:       aarpMachine,
+		pcapHandle: pcapHandle,
+	}
+	nbpCh := make(chan *ddp.ExtPacket, 1024)
+	go nbpMachine.Run(ctx, nbpCh)
+
 	// ---------- Raw AppleTalk/AARP inbound ----------
 	go func() {
 		for {
@@ -247,6 +255,9 @@ func main() {
 				case 1: // The RTMP socket
 					rtmpCh <- &ddpkt
 
+				case 2: // The NIS (NBP socket)
+					nbpCh <- &ddpkt
+
 				case 4: // The AEP socket
 					if err := handleAEP(pcapHandle, myHWAddr, ethFrame.Src, &ddpkt); err != nil {
 						log.Printf("AEP: Couldn't handle: %v", err)

nbp.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"context"
+	"log"
+
+	"gitea.drjosh.dev/josh/jrouter/atalk/nbp"
+	"github.com/google/gopacket/pcap"
+	"github.com/sfiera/multitalk/pkg/ddp"
+)
+
+type NBPMachine struct {
+	aarp       *AARPMachine
+	pcapHandle *pcap.Handle
+}
+
+func (NBPMachine) Run(ctx context.Context, incoming <-chan *ddp.ExtPacket) error {
+	for {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+
+		case ddpkt := <-incoming:
+			pkt, err := nbp.Unmarshal(ddpkt.Data)
+			if err != nil {
+				log.Printf("NBP: invalid packet: %v", err)
+				continue
+			}
+			// TODO:
+			log.Printf("NBP: Got %v", pkt.Function)
+		}
+	}
+}