1 files changed, 124 insertions, 0 deletions
diff --git a/bpf/main.go b/bpf/main.go
new file mode 100644
index 0000000..47fdc41
--- /dev/null
+++ b/bpf/main.go
@@ -0,0 +1,124 @@
+package bpf
+
+import (
+	"errors"
+	"fmt"
+	"log"
+	"net"
+	"time"
+
+	"github.com/cilium/ebpf"
+	"github.com/cilium/ebpf/link"
+)
+
+type UsageStat struct {
+	lastSeen time.Time
+	lastDbPush time.Time
+	ingress uint64
+	egress uint64
+}
+type UsageMap map[uint32]UsageStat
+
+func Run(iface *net.Interface) {
+	usageMap := make(UsageMap)
+
+	objs := bpfObjects{}
+	if err := loadBpfObjects(&objs, nil); err != nil {
+		log.Fatalf("loading objects: %s", err)
+	}
+	defer objs.Close()
+
+	ingressLink, err := link.AttachTCX(link.TCXOptions{
+		Interface: iface.Index,
+		Program:   objs.IngressFunc,
+		Attach:    ebpf.AttachTCXIngress,
+	})
+	if err != nil {
+		log.Fatalf("could not attach TCx program: %s", err)
+	}
+	defer ingressLink.Close()
+
+	egressLink, err := link.AttachTCX(link.TCXOptions{
+		Interface: iface.Index,
+		Program:   objs.EgressFunc,
+		Attach:    ebpf.AttachTCXEgress,
+	})
+	if err != nil {
+		log.Fatalf("could not attach TCx program: %s", err)
+	}
+	defer egressLink.Close()
+
+	bpfTicker := time.NewTicker(1 * time.Second)
+	defer bpfTicker.Stop()
+	dbTicker := time.NewTicker(60 * time.Second)
+	defer dbTicker.Stop()
+	for {
+		select {
+		case <-bpfTicker.C:
+			usageMap.update(objs.IngressIp4UsageMap, objs.EgressIp4UsageMap)
+		case <-dbTicker.C:
+			continue;
+		}
+	}
+}
+
+func (usageMap UsageMap) update(ingress *ebpf.Map, egress *ebpf.Map) {
+	timeStart := time.Now()
+	batchKeys := make([]uint32, 4096)
+	batchValues := make([]uint64, 4096)
+	var key uint32
+
+	cursor := ebpf.MapBatchCursor{}
+	for {
+		_, err := ingress.BatchLookupAndDelete(&cursor, batchKeys, batchValues, nil)
+		for i := range batchKeys {
+			key = batchKeys[i]
+			usage, ok := usageMap[key]
+			if ok {
+				usage.ingress += batchValues[i]
+				usage.lastSeen = timeStart
+				usageMap[key] = usage;
+			} else {
+				usageMap[key] = UsageStat {
+					ingress: batchValues[i],
+					lastDbPush: timeStart,
+					lastSeen: timeStart,
+				}
+			}
+		}
+
+		if (errors.Is(err, ebpf.ErrKeyNotExist)) {
+			break;
+		} else if err != nil{
+			fmt.Println(err)
+			break
+		}
+	}
+
+	cursor = ebpf.MapBatchCursor{}
+	for {
+		_, err := egress.BatchLookupAndDelete(&cursor, batchKeys, batchValues, nil)
+		for i := range batchKeys {
+			key = batchKeys[i]
+			usage, ok := usageMap[key]
+			if ok {
+				usage.egress += batchValues[i]
+				usage.lastSeen = timeStart
+				usageMap[key] = usage;
+			} else {
+				usageMap[key] = UsageStat {
+					egress: batchValues[i],
+					lastDbPush: timeStart,
+					lastSeen: timeStart,
+				}
+			}
+		}
+
+		if (errors.Is(err, ebpf.ErrKeyNotExist)) {
+			break;
+		} else if err != nil{
+			fmt.Println(err)
+			break
+		}
+	}
+}