add communicator api

capture/config.go

@@ -1,16 +1,17 @@
 package capture
 
 import (
-	sd "github.com/zr-hebo/sniffer-agent/session-dealer"
 	log "github.com/sirupsen/logrus"
-	"sync"
+	sd "github.com/zr-hebo/sniffer-agent/session-dealer"
+	"math/rand"
+	"time"
 )
 
 var (
 	localIPAddr *string
 
 	sessionPool = make(map[string]sd.ConnSession)
-	sessionPoolLock sync.Mutex
+	// sessionPoolLock sync.Mutex
 )
 
 func init() {
@@ -21,4 +22,6 @@ func init() {
 
 	localIPAddr = &ipAddr
 	log.Infof("parsed local ip address:%s", *localIPAddr)
+
+	rand.Seed(time.Now().UnixNano())
 }

capture/network.go

@@ -6,7 +6,9 @@ import (
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
 	"github.com/google/gopacket/pcap"
+	"github.com/zr-hebo/sniffer-agent/communicator"
 	"golang.org/x/net/bpf"
+	"math/rand"
 	"time"
 
 	"github.com/google/gopacket/pcapgo"
@@ -114,6 +116,20 @@ func (nc *networkCard) listenNormal() {
 				continue
 			}
 
+			// throw packets according to a certain probability
+			throwPacketRate := communicator.GetConfig(communicator.THROW_PACKET_RATE).(float64)
+			if throwPacketRate >= 1.0 {
+				time.Sleep(time.Second*3)
+				continue
+
+			} else if 0 < throwPacketRate && throwPacketRate < 1.0 {
+				// fall into throw range
+				rn := rand.Float64()
+				if rn <= throwPacketRate {
+					continue
+				}
+			}
+
 			packet := gopacket.NewPacket(data, layers.LayerTypeEthernet, gopacket.NoCopy)
 			m := packet.Metadata()
 			m.CaptureInfo = ci