feat: add ns-3 discrete-event simulation support (ndndSIM)

cmd/traffic/main.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"os"
+
+	"github.com/named-data/ndnd/tools"
+	"github.com/spf13/cobra"
+)
+
+func main() {
+	root := &cobra.Command{
+		Use:   "ndnd-traffic",
+		Short: "NDN traffic generator",
+	}
+	root.AddCommand(tools.CmdTraffic())
+	if err := root.Execute(); err != nil {
+		os.Exit(1)
+	}
+}

dv/config/config.go

@@ -6,6 +6,7 @@ import (
 	"time"
 
 	enc "github.com/named-data/ndnd/std/encoding"
+	"github.com/named-data/ndnd/std/ndn"
 	mgmt "github.com/named-data/ndnd/std/ndn/mgmt_2022"
 )
 
@@ -42,6 +43,11 @@ type Config struct {
 	// List of permanent neighbors.
 	Neighbors []Neighbor `json:"neighbors"`
 
+	// Pre-built KeyChain (bypasses KeyChainUri if set).
+	KeyChain ndn.KeyChain `json:"-"`
+	// Pre-built Store (bypasses internal store creation if set).
+	Store ndn.Store `json:"-"`
+
 	// Parsed Global Prefix
 	networkNameN enc.Name
 	// Parsed Router Prefix

dv/dv/advert_data.go

@@ -33,7 +33,7 @@ func (a *advertModule) generate() {
 	a.objDir.Evict(a.dv.client)
 
 	// Notify neighbors with sync for new advertisement
-	go a.sendSyncInterest()
+	a.dv.GoFunc(func() { a.sendSyncInterest() })
 }
 
 // (AI GENERATED DESCRIPTION): Fetches a neighbor’s DV advertisement Data packet (retrying on error) and invokes `dataHandler` with its content when the neighbor’s boot time and sequence number match the expected values.
@@ -56,14 +56,14 @@ func (a *advertModule) dataFetch(nName enc.Name, bootTime uint64, seqNo uint64)
 	a.dv.client.Consume(advName, func(state ndn.ConsumeState) {
 		if err := state.Error(); err != nil {
 			log.Warn(a, "Failed to fetch advertisement", "name", state.Name(), "err", err)
-			time.AfterFunc(1*time.Second, func() {
+			a.dv.engine.Timer().Schedule(1*time.Second, func() {
 				a.dataFetch(nName, bootTime, seqNo)
 			})
 			return
 		}
 
 		// Process the advertisement
-		go a.dataHandler(nName, seqNo, state.Content())
+		a.dv.GoFunc(func() { a.dataHandler(nName, seqNo, state.Content()) })
 	})
 }
 
@@ -92,5 +92,5 @@ func (a *advertModule) dataHandler(nName enc.Name, seqNo uint64, data enc.Wire)
 
 	// Update the local advertisement list
 	ns.Advert = advert
-	go a.dv.updateRib(ns)
+	a.dv.GoFunc(func() { a.dv.updateRib(ns) })
 }

dv/dv/advert_sync.go

@@ -143,7 +143,7 @@ func (a *advertModule) OnSyncInterest(args ndn.InterestHandlerArgs, active bool)
 			}
 
 			// Process the state vector
-			go a.onStateVector(params.StateVector, args.IncomingFaceId.Unwrap(), active)
+			a.dv.GoFunc(func() { a.onStateVector(params.StateVector, args.IncomingFaceId.Unwrap(), active) })
 		},
 	})
 }
@@ -197,13 +197,13 @@ func (a *advertModule) onStateVector(sv *spec_svs.StateVector, faceId uint64, ac
 		ns.AdvertBoot = entry.BootstrapTime
 		ns.AdvertSeq = entry.SeqNo
 
-		time.AfterFunc(10*time.Millisecond, func() { // debounce
+		a.dv.engine.Timer().Schedule(10*time.Millisecond, func() { // debounce
 			a.dataFetch(node.Name, entry.BootstrapTime, entry.SeqNo)
 		})
 	}
 
 	// Update FIB if needed
 	if fibDirty {
-		go a.dv.updateFib()
+		a.dv.GoFunc(a.dv.updateFib)
 	}
 }

dv/dv/router.go

@@ -7,6 +7,7 @@ import (
 	"github.com/named-data/ndnd/dv/config"
 	"github.com/named-data/ndnd/dv/nfdc"
 	"github.com/named-data/ndnd/dv/table"
+	"github.com/named-data/ndnd/fw/core"
 	enc "github.com/named-data/ndnd/std/encoding"
 	"github.com/named-data/ndnd/std/log"
 	"github.com/named-data/ndnd/std/ndn"
@@ -37,6 +38,19 @@ type Router struct {
 	// single mutex for all operations
 	mutex sync.Mutex
 
+	// GoFunc dispatches work asynchronously.
+	// In production, this launches a goroutine.
+	// In simulation, this schedules via the simulation clock.
+	GoFunc func(func())
+
+	// NowFunc returns current time. Defaults to time.Now.
+	// In simulation, returns simulation clock time.
+	NowFunc func() time.Time
+
+	// AfterFunc schedules f after d. Returns cancel function.
+	// Defaults to time.AfterFunc wrapper.
+	AfterFunc func(time.Duration, func()) func()
+
 	// channel to stop the DV
 	stop chan bool
 	// heartbeat for outgoing Advertisements
@@ -70,12 +84,29 @@ func NewRouter(config *config.Config, engine ndn.Engine) (*Router, error) {
 		return nil, err
 	}
 
-	// Create packet store
-	store := storage.NewMemoryStore()
+	// Create packet store (use pre-built store if provided)
+	var store ndn.Store
+	if config.Store != nil {
+		store = config.Store
+	} else {
+		store = storage.NewMemoryStore()
+	}
 
 	// Create security configuration
 	var trust *sec.TrustConfig = nil
-	if config.KeyChainUri == "insecure" {
+	if config.KeyChain != nil {
+		// Use pre-built keychain (e.g. from simulation trust setup)
+		schema, err := trust_schema.NewLvsSchema(config.SchemaBytes())
+		if err != nil {
+			return nil, err
+		}
+		anchors := config.TrustAnchorNames()
+		trust, err = sec.NewTrustConfig(config.KeyChain, schema, anchors)
+		if err != nil {
+			return nil, err
+		}
+		trust.UseDataNameFwHint = true
+	} else if config.KeyChainUri == "insecure" {
 		log.Warn(nil, "Security is disabled - insecure mode")
 	} else {
 		kc, err := keychain.NewKeyChain(config.KeyChainUri, store)
@@ -98,25 +129,34 @@ func NewRouter(config *config.Config, engine ndn.Engine) (*Router, error) {
 
 	// Create the DV router
 	dv := &Router{
-		engine: engine,
-		config: config,
-		trust:  trust,
-		client: object.NewClient(engine, store, trust),
-		nfdc:   nfdc.NewNfdMgmtThread(engine),
-		mutex:  sync.Mutex{},
+		engine:  engine,
+		config:  config,
+		trust:   trust,
+		client:  object.NewClient(engine, store, trust),
+		nfdc:    nfdc.NewNfdMgmtThread(engine),
+		mutex:   sync.Mutex{},
+		GoFunc:  func(f func()) { go f() },
+		NowFunc: core.Now,
+		AfterFunc: func(d time.Duration, f func()) func() {
+			t := time.AfterFunc(d, f)
+			return func() { t.Stop() }
+		},
 	}
 
-	// Initialize advertisement module
+	// Initialize advertisement module.
+	// NOTE: bootTime must NOT be computed here — NowFunc may still point to
+	// the real wall clock at construction time.  For production Start() and
+	// simulation Init(), bootTime is computed lazily via dv.NowFunc() at the
+	// start of those methods, after any override (e.g. SimDvRouter) is in place.
+	// createPrefixTable() is also deferred for the same reason: it embeds
+	// bootTime into pfxSvs, which would then compare incoming BootstrapTimes
+	// against the wrong clock.
 	dv.advert = advertModule{
-		dv:       dv,
-		bootTime: uint64(time.Now().Unix()),
-		seq:      0,
-		objDir:   storage.NewMemoryFifoDir(32), // keep last few advertisements
+		dv:     dv,
+		seq:    0,
+		objDir: storage.NewMemoryFifoDir(32), // keep last few advertisements
 	}
 
-	// Create prefix table
-	dv.createPrefixTable()
-
 	// Create DV tables
 	dv.neighbors = table.NewNeighborTable(config, dv.nfdc)
 	dv.rib = table.NewRib(config)
@@ -135,6 +175,11 @@ func (dv *Router) Start() (err error) {
 	log.Info(dv, "Starting DV router", "version", utils.NDNdVersion)
 	defer log.Info(dv, "Stopped DV router")
 
+	// Lazily initialize bootTime and prefix table so that any NowFunc
+	// override (e.g. from simulation) is in effect before pfxSvs is created.
+	dv.advert.bootTime = max(uint64(dv.NowFunc().Unix()), 1)
+	dv.createPrefixTable()
+
 	// Initialize channels
 	dv.stop = make(chan bool, 1)
 
@@ -153,7 +198,7 @@ func (dv *Router) Start() (err error) {
 	defer dv.client.Stop()
 
 	// Start management thread
-	go dv.nfdc.Start()
+	dv.GoFunc(func() { dv.nfdc.Start() })
 	defer dv.nfdc.Stop()
 
 	// Configure face
@@ -194,6 +239,71 @@ func (dv *Router) Stop() {
 	dv.stop <- true
 }
 
+// Init initializes the DV router without blocking.
+// This is the simulation-compatible variant of Start() — it performs all
+// setup (faces, handlers, sync groups, initial advertisement) but returns
+// immediately instead of entering a ticker-driven select loop.
+// The caller is responsible for periodically calling RunHeartbeat() and
+// RunDeadcheck() using the simulation clock.
+func (dv *Router) Init() error {
+	log.Info(dv, "Initializing DV router (sim)", "version", utils.NDNdVersion)
+
+	// Lazily initialize bootTime and prefix table so that the NowFunc
+	// override installed by SimDvRouter (clock.Now) is used instead of the
+	// wall clock.  If bootTime were set at NewRouter() time, it would carry
+	// the real Unix timestamp (~1773989593 in 2026), which SVS on every peer
+	// would reject as "far future" because the simulation clock starts near
+	// the Unix epoch.
+	dv.advert.bootTime = max(uint64(dv.NowFunc().Unix()), 1)
+	dv.createPrefixTable()
+
+	// Start object client
+	dv.client.Start()
+
+	// Register interest handlers
+	if err := dv.register(); err != nil {
+		return err
+	}
+
+	// Start sync groups
+	dv.pfxSvs.Start()
+
+	// Add self to the RIB and make initial advertisement
+	dv.rib.Set(dv.config.RouterName(), dv.config.RouterName(), 0)
+	dv.advert.generate()
+
+	// Initialize prefix table
+	dv.pfx.Reset()
+
+	return nil
+}
+
+// RunHeartbeat sends a sync Interest to all neighbors.
+// In production this is driven by time.Ticker; in simulation it is
+// called by the simulation clock scheduler.
+func (dv *Router) RunHeartbeat() {
+	dv.advert.sendSyncInterest()
+}
+
+// RunDeadcheck checks for dead neighbors and prunes routes.
+// In production this is driven by time.Ticker; in simulation it is
+// called by the simulation clock scheduler.
+func (dv *Router) RunDeadcheck() {
+	dv.checkDeadNeighbors()
+}
+
+// Cleanup tears down the DV router (simulation variant of deferred cleanup in Start).
+func (dv *Router) Cleanup() {
+	dv.pfxSvs.Stop()
+	dv.client.Stop()
+	log.Info(dv, "Cleaned up DV router (sim)")
+}
+
+// Nfdc returns the NFD management thread.
+func (dv *Router) Nfdc() *nfdc.NfdMgmtThread {
+	return dv.nfdc
+}
+
 // Configure the face to forwarder.
 func (dv *Router) configureFace() (err error) {
 	// Enable local fields on face. This includes incoming face indication.
@@ -215,7 +325,7 @@ func (dv *Router) register() (err error) {
 	// Advertisement Sync (active)
 	err = dv.engine.AttachHandler(dv.config.AdvertisementSyncActivePrefix(),
 		func(args ndn.InterestHandlerArgs) {
-			go dv.advert.OnSyncInterest(args, true)
+			dv.GoFunc(func() { dv.advert.OnSyncInterest(args, true) })
 		})
 	if err != nil {
 		return err
@@ -224,7 +334,7 @@ func (dv *Router) register() (err error) {
 	// Advertisement Sync (passive)
 	err = dv.engine.AttachHandler(dv.config.AdvertisementSyncPassivePrefix(),
 		func(args ndn.InterestHandlerArgs) {
-			go dv.advert.OnSyncInterest(args, false)
+			dv.GoFunc(func() { dv.advert.OnSyncInterest(args, false) })
 		})
 	if err != nil {
 		return err
@@ -233,7 +343,7 @@ func (dv *Router) register() (err error) {
 	// Router management
 	err = dv.engine.AttachHandler(dv.config.MgmtPrefix(),
 		func(args ndn.InterestHandlerArgs) {
-			go dv.mgmtOnInterest(args)
+			dv.GoFunc(func() { dv.mgmtOnInterest(args) })
 		})
 	if err != nil {
 		return err
@@ -355,6 +465,9 @@ func (dv *Router) createPrefixTable() {
 			Client:      dv.client,
 			GroupPrefix: dv.config.PrefixTableGroupPrefix(),
 			BootTime:    dv.advert.bootTime,
+			GoFunc:      func(f func()) { dv.GoFunc(f) },
+			NowFunc:     func() time.Time { return dv.NowFunc() },
+			AfterFunc:   func(d time.Duration, f func()) func() { return dv.AfterFunc(d, f) },
 		},
 		Snapshot: &ndn_sync.SnapshotNodeLatest{
 			Client: dv.client,
@@ -373,5 +486,7 @@ func (dv *Router) createPrefixTable() {
 		if _, _, err := dv.pfxSvs.Publish(w); err != nil {
 			log.Error(dv, "Failed to publish prefix table update", "err", err)
 		}
+	}, table.PrefixTableOptions{
+		NowFunc: dv.NowFunc,
 	})
 }