From 0358eea5a4fd2e73224e4b48ea7ac5b68213720f Mon Sep 17 00:00:00 2001
From: Josh Deprez <josh.deprez@gmail.com>
Date: Mon, 1 Apr 2024 15:33:57 +1100
Subject: [PATCH] Handle GDZL and GZN

---
 aurp/routing_info.go | 11 +++++++++
 aurp/transport.go    | 57 ++++++++++++++++++++++++++++++++++++++++++++
 peer.go              | 19 +++++++++++++++
 3 files changed, 87 insertions(+)

diff --git a/aurp/routing_info.go b/aurp/routing_info.go
index c716e8d..5963cb5 100644
--- a/aurp/routing_info.go
+++ b/aurp/routing_info.go
@@ -239,3 +239,14 @@ const (
 	EventCodeNDC  EventCode = 4
 	EventCodeZC   EventCode = 5
 )
+
+func (ec EventCode) String() string {
+	return map[EventCode]string{
+		EventCodeNull: "null",
+		EventCodeNA:   "network added",
+		EventCodeND:   "network deleted",
+		EventCodeNRC:  "network route change",
+		EventCodeNDC:  "network distance change",
+		EventCodeZC:   "zone name change",
+	}[ec]
+}
diff --git a/aurp/transport.go b/aurp/transport.go
index 40ede57..e9bf0b3 100644
--- a/aurp/transport.go
+++ b/aurp/transport.go
@@ -209,6 +209,63 @@ func (tr *Transport) NewZIRspPacket(zones ZoneTuples) *ZIRspPacket {
 	}
 }
 
+// NewGDZLReqPacket returns a new GDZL-Req packet structure.
+func (tr *Transport) NewGDZLReqPacket(startIdx uint16) *GDZLReqPacket {
+	return &GDZLReqPacket{
+		Header: Header{
+			TrHeader:    tr.transaction(tr.LocalConnID),
+			CommandCode: CmdCodeZoneReq,
+			Flags:       0,
+		},
+		Subcode:    SubcodeGetDomainZoneList,
+		StartIndex: startIdx,
+	}
+}
+
+// NewGZNRspPacket returns a new GDZL-Rsp packet structure. If GDZL function is
+// not supported, startIdx should be set to -1.
+func (tr *Transport) NewGDZLRspPacket(startIdx int16, zoneNames []string) *GDZLRspPacket {
+	return &GDZLRspPacket{
+		Header: Header{
+			TrHeader:    tr.transaction(tr.RemoteConnID),
+			CommandCode: CmdCodeZoneReq,
+			Flags:       0,
+		},
+		Subcode:    SubcodeGetDomainZoneList,
+		StartIndex: startIdx,
+		ZoneNames:  zoneNames,
+	}
+}
+
+// NewGZNReqPacket returns a new GZN-Req packet structure requesting nets for a
+// given zone name.
+func (tr *Transport) NewGZNReqPacket(zoneName string) *GZNReqPacket {
+	return &GZNReqPacket{
+		Header: Header{
+			TrHeader:    tr.transaction(tr.LocalConnID),
+			CommandCode: CmdCodeZoneReq,
+			Flags:       0,
+		},
+		Subcode:  SubcodeGetZonesNet,
+		ZoneName: zoneName,
+	}
+}
+
+// NewGZNRspPacket returns a new GZN-Rsp packet structure.
+func (tr *Transport) NewGZNRspPacket(zoneName string, notSupported bool, nets NetworkTuples) *GZNRspPacket {
+	return &GZNRspPacket{
+		Header: Header{
+			TrHeader:    tr.transaction(tr.RemoteConnID),
+			CommandCode: CmdCodeZoneReq,
+			Flags:       0,
+		},
+		Subcode:      SubcodeGetZonesNet,
+		ZoneName:     zoneName,
+		NotSupported: notSupported,
+		Networks:     nets,
+	}
+}
+
 // NewRDPacket returns a new RD packet structure.
 func (tr *Transport) NewRDPacket(errCode ErrorCode) *RDPacket {
 	return &RDPacket{
diff --git a/peer.go b/peer.go
index 2b1234b..ed94a39 100644
--- a/peer.go
+++ b/peer.go
@@ -345,12 +345,31 @@ func (p *peer) handle(ctx context.Context) error {
 				}
 				if _, err := p.send(p.tr.NewZIRspPacket(zones)); err != nil {
 					log.Printf("Couldn't send ZI-Rsp packet: %v", err)
+					return err
 				}
 
 			case *aurp.ZIRspPacket:
 				// TODO: Integrate info into zone table
 				log.Printf("Learned about these zones: %v", pkt.Zones)
 
+			case *aurp.GDZLReqPacket:
+				if _, err := p.send(p.tr.NewGDZLRspPacket(-1, nil)); err != nil {
+					log.Printf("Couldn't send GDZL-Rsp packet: %v", err)
+					return err
+				}
+
+			case *aurp.GDZLRspPacket:
+				log.Printf("Received a GDZL-Rsp, but I wouldn't have sent a GDZL-Req - that's weird")
+
+			case *aurp.GZNReqPacket:
+				if _, err := p.send(p.tr.NewGZNRspPacket(pkt.ZoneName, false, nil)); err != nil {
+					log.Printf("Couldn't send GZN-Rsp packet: %v", err)
+					return err
+				}
+
+			case *aurp.GZNRspPacket:
+				log.Printf("Received a GZN-Rsp, but I wouldn't have sent a GZN-Req - that's weird")
+
 			case *aurp.TicklePacket:
 				// Immediately respond with Tickle-Ack
 				if _, err := p.send(p.tr.NewTickleAckPacket()); err != nil {