From f06dba7458189db6ffb7b9bc8b22dcc99dd25d5f Mon Sep 17 00:00:00 2001
From: tsosunchia <59512455+tsosunchia@users.noreply.github.com>
Date: Thu, 30 May 2024 00:01:11 +0800
Subject: [PATCH] =?UTF-8?q?ipv6=20tcp=E5=BA=94=E7=94=A8pktsize?=
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---
 trace/tcp_ipv4.go |  2 +-
 trace/tcp_ipv6.go | 14 +++++++++-----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/trace/tcp_ipv4.go b/trace/tcp_ipv4.go
index 5482230..170dea1 100644
--- a/trace/tcp_ipv4.go
+++ b/trace/tcp_ipv4.go
@@ -217,7 +217,7 @@ func (t *TCPTracer) send(ttl int) error {
 		DstIP:    t.DestIP,
 		Protocol: layers.IPProtocolTCP,
 		TTL:      uint8(ttl),
-		Flags:    layers.IPv4DontFragment,
+		//Flags:    layers.IPv4DontFragment, // 我感觉没必要
 	}
 	// 使用Uint16兼容32位系统，防止在rand的时候因使用int32而溢出
 	sequenceNumber := uint32(r.Intn(math.MaxUint16))
diff --git a/trace/tcp_ipv6.go b/trace/tcp_ipv6.go
index 884acfd..801d1c9 100644
--- a/trace/tcp_ipv6.go
+++ b/trace/tcp_ipv6.go
@@ -227,9 +227,16 @@ func (t *TCPTracerv6) send(ttl int) error {
 
 	desiredPayloadSize := t.Config.PktSize
 	payload := make([]byte, desiredPayloadSize)
-	copy(buf.Bytes(), payload)
+	// 设置随机种子
+	rand.Seed(time.Now().UnixNano())
 
-	if err := gopacket.SerializeLayers(buf, opts, tcpHeader); err != nil {
+	// 填充随机数
+	for i := range payload {
+		payload[i] = byte(rand.Intn(256))
+	}
+	//copy(buf.Bytes(), payload)
+
+	if err := gopacket.SerializeLayers(buf, opts, tcpHeader, gopacket.Payload(payload)); err != nil {
 		return err
 	}
 
@@ -237,9 +244,6 @@ func (t *TCPTracerv6) send(ttl int) error {
 	if err != nil {
 		return err
 	}
-	if err != nil {
-		return err
-	}
 
 	start := time.Now()
 	if _, err := t.tcp.WriteTo(buf.Bytes(), &net.IPAddr{IP: t.DestIP}); err != nil {