[client,management] add netflow support to client and update management (#3414)

adds NetFlow functionality to track and log network traffic information between peers, with features including:

- Flow logging for TCP, UDP, and ICMP traffic
- Integration with connection tracking system
- Resource ID tracking in NetFlow events
- DNS and exit node collection configuration
- Flow API and Redis cache in management
- Memory-based flow storage implementation
- Kernel conntrack counters and userspace counters
- TCP state machine improvements for more accurate tracking
- Migration from net.IP to netip.Addr in the userspace firewall

client/internal/netflow/logger/logger.go

@@ -0,0 +1,162 @@
+package logger
+
+import (
+	"context"
+	"net"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"github.com/google/uuid"
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/internal/dnsfwd"
+	"github.com/netbirdio/netbird/client/internal/netflow/store"
+	"github.com/netbirdio/netbird/client/internal/netflow/types"
+	"github.com/netbirdio/netbird/client/internal/peer"
+)
+
+type rcvChan chan *types.EventFields
+type Logger struct {
+	mux                sync.Mutex
+	ctx                context.Context
+	cancel             context.CancelFunc
+	enabled            atomic.Bool
+	rcvChan            atomic.Pointer[rcvChan]
+	cancelReceiver     context.CancelFunc
+	statusRecorder     *peer.Status
+	wgIfaceIPNet       net.IPNet
+	dnsCollection      atomic.Bool
+	exitNodeCollection atomic.Bool
+	Store              types.Store
+}
+
+func New(ctx context.Context, statusRecorder *peer.Status, wgIfaceIPNet net.IPNet) *Logger {
+
+	ctx, cancel := context.WithCancel(ctx)
+	return &Logger{
+		ctx:            ctx,
+		cancel:         cancel,
+		statusRecorder: statusRecorder,
+		wgIfaceIPNet:   wgIfaceIPNet,
+		Store:          store.NewMemoryStore(),
+	}
+}
+
+func (l *Logger) StoreEvent(flowEvent types.EventFields) {
+	if !l.enabled.Load() {
+		return
+	}
+
+	c := l.rcvChan.Load()
+	if c == nil {
+		return
+	}
+
+	select {
+	case *c <- &flowEvent:
+	default:
+		// todo: we should collect or log on this
+	}
+}
+
+func (l *Logger) Enable() {
+	go l.startReceiver()
+}
+
+func (l *Logger) startReceiver() {
+	if l.enabled.Load() {
+		return
+	}
+
+	l.mux.Lock()
+	ctx, cancel := context.WithCancel(l.ctx)
+	l.cancelReceiver = cancel
+	l.mux.Unlock()
+
+	c := make(rcvChan, 100)
+	l.rcvChan.Store(&c)
+	l.enabled.Store(true)
+
+	for {
+		select {
+		case <-ctx.Done():
+			log.Info("flow Memory store receiver stopped")
+			return
+		case eventFields := <-c:
+			id := uuid.New()
+			event := types.Event{
+				ID:          id,
+				EventFields: *eventFields,
+				Timestamp:   time.Now(),
+			}
+
+			var isExitNode bool
+			if event.Direction == types.Ingress {
+				if !l.wgIfaceIPNet.Contains(net.IP(event.SourceIP.AsSlice())) {
+					event.SourceResourceID, isExitNode = l.statusRecorder.CheckRoutes(event.SourceIP)
+				}
+			} else if event.Direction == types.Egress {
+				if !l.wgIfaceIPNet.Contains(net.IP(event.DestIP.AsSlice())) {
+					event.DestResourceID, isExitNode = l.statusRecorder.CheckRoutes(event.DestIP)
+				}
+			}
+
+			if l.shouldStore(eventFields, isExitNode) {
+				l.Store.StoreEvent(&event)
+			}
+		}
+	}
+}
+
+func (l *Logger) Disable() {
+	l.stop()
+	l.Store.Close()
+}
+
+func (l *Logger) stop() {
+	if !l.enabled.Load() {
+		return
+	}
+
+	l.enabled.Store(false)
+	l.mux.Lock()
+	if l.cancelReceiver != nil {
+		l.cancelReceiver()
+		l.cancelReceiver = nil
+	}
+	l.rcvChan.Store(nil)
+	l.mux.Unlock()
+}
+
+func (l *Logger) GetEvents() []*types.Event {
+	return l.Store.GetEvents()
+}
+
+func (l *Logger) DeleteEvents(ids []uuid.UUID) {
+	l.Store.DeleteEvents(ids)
+}
+
+func (l *Logger) UpdateConfig(dnsCollection, exitNodeCollection bool) {
+	l.dnsCollection.Store(dnsCollection)
+	l.exitNodeCollection.Store(exitNodeCollection)
+}
+
+func (l *Logger) Close() {
+	l.stop()
+	l.cancel()
+}
+
+func (l *Logger) shouldStore(event *types.EventFields, isExitNode bool) bool {
+	// check dns collection
+	if !l.dnsCollection.Load() && event.Protocol == types.UDP && (event.DestPort == 53 || event.DestPort == dnsfwd.ListenPort) {
+		return false
+	}
+
+	// check exit node collection
+	if !l.exitNodeCollection.Load() && isExitNode {
+		return false
+	}
+
+	return true
+}