diff --git a/binary/writer.go b/binary/writer.go
index 02c62645..18d8a8e6 100644
--- a/binary/writer.go
+++ b/binary/writer.go
@@ -24,37 +24,26 @@ func OpenWriterF(f func(*Writer)) (b []byte, cl func()) {
 	return w.Bytes(), w.put
 }
 
-func (w *Writer) AllocUInt16Head() (pos int) {
-	pos = (*bytes.Buffer)(w).Len()
+func (w *Writer) FillUInt16() (pos int) {
+	pos = w.Len()
 	(*bytes.Buffer)(w).Write([]byte{0, 0})
 	return
 }
 
-/*
-func (w *Writer) WriteUInt16HeadAt(pos int) {
+func (w *Writer) WriteUInt16At(pos int, v uint16) {
 	newdata := (*bytes.Buffer)(w).Bytes()[pos:]
-	binary.BigEndian.PutUint16(newdata, uint16(len(newdata)))
-}
-*/
-
-func (w *Writer) WriteUInt16HeadUsingTotalBufferLenAt(pos int) {
-	binary.BigEndian.PutUint16((*bytes.Buffer)(w).Bytes()[pos:], uint16((*bytes.Buffer)(w).Len()))
+	binary.BigEndian.PutUint16(newdata, v)
 }
 
-func (w *Writer) WriteUInt16HeadExcludeSelfAt(pos int) {
-	newdata := (*bytes.Buffer)(w).Bytes()[pos:]
-	binary.BigEndian.PutUint16(newdata, uint16(len(newdata)-2))
-}
-
-func (w *Writer) AllocUInt32Head() (pos int) {
-	pos = (*bytes.Buffer)(w).Len()
+func (w *Writer) FillUInt32() (pos int) {
+	pos = w.Len()
 	(*bytes.Buffer)(w).Write([]byte{0, 0, 0, 0})
 	return
 }
 
-func (w *Writer) WriteUInt32HeadAt(pos int) {
+func (w *Writer) WriteUInt32At(pos int, v uint32) {
 	newdata := (*bytes.Buffer)(w).Bytes()[pos:]
-	binary.BigEndian.PutUint32(newdata, uint32(len(newdata)))
+	binary.BigEndian.PutUint32(newdata, v)
 }
 
 func (w *Writer) Write(b []byte) {
@@ -111,10 +100,9 @@ func (w *Writer) EncryptAndWrite(key []byte, data []byte) {
 }
 
 func (w *Writer) WriteIntLvPacket(offset int, f func(*Writer)) {
-	data, cl := OpenWriterF(f)
-	w.WriteUInt32(uint32(len(data) + offset))
-	w.Write(data)
-	cl()
+	w.FillUInt32()
+	f(w)
+	w.WriteUInt32At(0, uint32(w.Len()-4+offset))
 }
 
 func (w *Writer) WriteBytesShort(data []byte) {
@@ -130,6 +118,10 @@ func (w *Writer) WriteTlvLimitedSize(data []byte, limit int) {
 	w.WriteBytesShort(data[:limit])
 }
 
+func (w *Writer) Len() int {
+	return (*bytes.Buffer)(w).Len()
+}
+
 func (w *Writer) Bytes() []byte {
 	return (*bytes.Buffer)(w).Bytes()
 }
diff --git a/client/builders.go b/client/builders.go
index b762448d..032a4f1d 100644
--- a/client/builders.go
+++ b/client/builders.go
@@ -199,12 +199,10 @@ func (c *QQClient) buildQRCodeLoginPacket(t106, t16a, t318 []byte) (uint16, []by
 
 		w.Write(tlv.T18(16, uint32(c.Uin)))
 		w.Write(tlv.T1(uint32(c.Uin), c.deviceInfo.IpAddress))
-		wb, cl := binary.OpenWriterF(func(bw *binary.Writer) {
-			bw.WriteUInt16(0x106)
-			bw.WriteBytesShort(t106)
-		})
-		w.Write(wb)
-		cl()
+
+		w.WriteUInt16(0x106)
+		w.WriteBytesShort(t106)
+
 		// w.Write(tlv.T106(uint32(c.Uin), 0, c.version.AppId, c.version.SSOVersion, c.PasswordMd5, true, c.deviceInfo.Guid, c.deviceInfo.TgtgtKey, 0))
 		w.Write(tlv.T116(c.version.MiscBitmap, c.version.SubSigmap))
 		w.Write(tlv.T100(c.version.SSOVersion, c.version.SubAppId, c.version.MainSigMap))
@@ -226,12 +224,10 @@ func (c *QQClient) buildQRCodeLoginPacket(t106, t16a, t318 []byte) (uint16, []by
 
 		w.Write(tlv.T145(c.deviceInfo.Guid))
 		w.Write(tlv.T147(16, []byte(c.version.SortVersionName), c.version.ApkSign))
-		wb, cl = binary.OpenWriterF(func(bw *binary.Writer) {
-			bw.WriteUInt16(0x16A)
-			bw.WriteBytesShort(t16a)
-		})
-		w.Write(wb)
-		cl()
+
+		w.WriteUInt16(0x16A)
+		w.WriteBytesShort(t16a)
+
 		w.Write(tlv.T154(seq))
 		w.Write(tlv.T141(c.deviceInfo.SimInfo, c.deviceInfo.APN))
 		w.Write(tlv.T8(2052))
@@ -253,12 +249,9 @@ func (c *QQClient) buildQRCodeLoginPacket(t106, t16a, t318 []byte) (uint16, []by
 		w.Write(tlv.T516())
 		w.Write(tlv.T521(8))
 		// w.Write(tlv.T525(tlv.T536([]byte{0x01, 0x00})))
-		wb, cl = binary.OpenWriterF(func(bw *binary.Writer) {
-			bw.WriteUInt16(0x318)
-			bw.WriteBytesShort(t318)
-		})
-		w.Write(wb)
-		cl()
+
+		w.WriteUInt16(0x318)
+		w.WriteBytesShort(t318)
 	}))
 
 	req2 := network.Request{
@@ -377,12 +370,10 @@ func (c *QQClient) buildRequestTgtgtNopicsigPacket() (uint16, []byte) {
 
 		w.Write(tlv.T18(16, uint32(c.Uin)))
 		w.Write(tlv.T1(uint32(c.Uin), c.deviceInfo.IpAddress))
-		wb, cl := binary.OpenWriterF(func(bw *binary.Writer) {
-			bw.WriteUInt16(0x106)
-			bw.WriteBytesShort(c.sig.EncryptedA1)
-		})
-		w.Write(wb)
-		cl()
+
+		w.WriteUInt16(0x106)
+		w.WriteBytesShort(c.sig.EncryptedA1)
+
 		w.Write(tlv.T116(c.version.MiscBitmap, c.version.SubSigmap))
 		w.Write(tlv.T100(c.version.SSOVersion, 2, c.version.MainSigMap))
 		w.Write(tlv.T107(0))
diff --git a/client/internal/network/transport.go b/client/internal/network/transport.go
index cf0b0317..839c8cc2 100644
--- a/client/internal/network/transport.go
+++ b/client/internal/network/transport.go
@@ -66,7 +66,7 @@ func (t *Transport) PackPacket(req *Request) []byte {
 	}
 
 	return binary.NewWriterF(func(w *binary.Writer) {
-		pos := w.AllocUInt32Head()
+		pos := w.FillUInt32()
 		// vvv w.Write(head) vvv
 		w.WriteUInt32(uint32(req.Type))
 		w.WriteByte(byte(req.EncryptType))
@@ -100,7 +100,7 @@ func (t *Transport) PackPacket(req *Request) []byte {
 				t.packBody(req, w)
 			}
 		}))
-		w.WriteUInt32HeadAt(pos)
+		w.WriteUInt32At(pos, uint32(w.Len()))
 	})
 }
 
diff --git a/internal/packets/global.go b/internal/packets/global.go
index 3ef09564..8ea50ab3 100644
--- a/internal/packets/global.go
+++ b/internal/packets/global.go
@@ -32,7 +32,7 @@ type IncomingPacket struct {
 func BuildCode2DRequestPacket(seq uint32, j uint64, cmd uint16, bodyFunc func(writer *binary.Writer)) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteByte(2)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(cmd)
 		w.Write(make([]byte, 21))
 		w.WriteByte(3)
@@ -42,7 +42,7 @@ func BuildCode2DRequestPacket(seq uint32, j uint64, cmd uint16, bodyFunc func(wr
 		w.WriteUInt64(j)
 		bodyFunc(w)
 		w.WriteByte(3)
-		w.WriteUInt16HeadUsingTotalBufferLenAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()))
 	})
 }
 
diff --git a/internal/tlv/t1.go b/internal/tlv/t1.go
index e2f01809..0b79129f 100644
--- a/internal/tlv/t1.go
+++ b/internal/tlv/t1.go
@@ -13,13 +13,13 @@ func T1(uin uint32, ip []byte) []byte {
 	}
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x01)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(1)
 		w.WriteUInt32(rand.Uint32())
 		w.WriteUInt32(uin)
 		w.WriteUInt32(uint32(time.Now().UnixNano() / 1e6))
 		w.Write(ip)
 		w.WriteUInt16(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t100.go b/internal/tlv/t100.go
index dc0693f2..c4d42ef0 100644
--- a/internal/tlv/t100.go
+++ b/internal/tlv/t100.go
@@ -7,13 +7,13 @@ import (
 func T100(ssoVersion, protocol, mainSigMap uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x100)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(1)
 		w.WriteUInt32(ssoVersion)
 		w.WriteUInt32(16)
 		w.WriteUInt32(protocol)
 		w.WriteUInt32(0)          // App client version
 		w.WriteUInt32(mainSigMap) // 34869472
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t106.go b/internal/tlv/t106.go
index 24090b7d..7ae6dbbb 100644
--- a/internal/tlv/t106.go
+++ b/internal/tlv/t106.go
@@ -12,7 +12,7 @@ import (
 func T106(uin, salt, appId, ssoVer uint32, passwordMd5 [16]byte, guidAvailable bool, guid, tgtgtKey []byte, wtf uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x106)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		keydata, kcl := binary.OpenWriterF(func(w *binary.Writer) {
 			w.Write(passwordMd5[:])
 			w.WriteUInt32(0) // []byte{0x00, 0x00, 0x00, 0x00}...
@@ -56,7 +56,7 @@ func T106(uin, salt, appId, ssoVer uint32, passwordMd5 [16]byte, guidAvailable b
 			w.WriteUInt16(0)
 		})
 		w.EncryptAndWrite(key[:], body)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 		cl()
 	})
 }
diff --git a/internal/tlv/t107.go b/internal/tlv/t107.go
index 5739c5cb..427f29f9 100644
--- a/internal/tlv/t107.go
+++ b/internal/tlv/t107.go
@@ -5,11 +5,11 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T107(picType uint16) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x107)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(picType)
 		w.WriteByte(0x00)
 		w.WriteUInt16(0)
 		w.WriteByte(0x01)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t109.go b/internal/tlv/t109.go
index 638fad4f..6f86b465 100644
--- a/internal/tlv/t109.go
+++ b/internal/tlv/t109.go
@@ -9,9 +9,9 @@ import (
 func T109(androidId []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x109)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		h := md5.Sum(androidId)
 		w.Write(h[:])
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t116.go b/internal/tlv/t116.go
index 9b70bae2..09ccb4c3 100644
--- a/internal/tlv/t116.go
+++ b/internal/tlv/t116.go
@@ -5,12 +5,12 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T116(miscBitmap, subSigMap uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x116)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteByte(0x00)
 		w.WriteUInt32(miscBitmap)
 		w.WriteUInt32(subSigMap)
 		w.WriteByte(0x01)
 		w.WriteUInt32(1600000226) // app id list
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t124.go b/internal/tlv/t124.go
index 21fe35f2..5d4f65a8 100644
--- a/internal/tlv/t124.go
+++ b/internal/tlv/t124.go
@@ -5,13 +5,13 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T124(osType, osVersion, simInfo, apn []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x124)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteTlvLimitedSize(osType, 16)
 		w.WriteTlvLimitedSize(osVersion, 16)
 		w.WriteUInt16(2) // Network type wifi
 		w.WriteTlvLimitedSize(simInfo, 16)
 		w.WriteTlvLimitedSize([]byte{}, 16)
 		w.WriteTlvLimitedSize(apn, 16)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t128.go b/internal/tlv/t128.go
index e24d023a..ed9adbfe 100644
--- a/internal/tlv/t128.go
+++ b/internal/tlv/t128.go
@@ -5,7 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T128(isGuidFromFileNull, isGuidAvailable, isGuidChanged bool, guidFlag uint32, buildModel, guid, buildBrand []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x128)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(0)
 		w.WriteBool(isGuidFromFileNull)
 		w.WriteBool(isGuidAvailable)
@@ -14,6 +14,6 @@ func T128(isGuidFromFileNull, isGuidAvailable, isGuidChanged bool, guidFlag uint
 		w.WriteTlvLimitedSize(buildModel, 32)
 		w.WriteTlvLimitedSize(guid, 16)
 		w.WriteTlvLimitedSize(buildBrand, 16)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t141.go b/internal/tlv/t141.go
index 2d45ae9e..811cef25 100644
--- a/internal/tlv/t141.go
+++ b/internal/tlv/t141.go
@@ -5,11 +5,11 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T141(simInfo, apn []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x141)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(1)
 		w.WriteBytesShort(simInfo)
 		w.WriteUInt16(2) // network type wifi
 		w.WriteBytesShort(apn)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t142.go b/internal/tlv/t142.go
index 46752be3..04a246ad 100644
--- a/internal/tlv/t142.go
+++ b/internal/tlv/t142.go
@@ -5,9 +5,9 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T142(apkId string) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x142)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(0)
 		w.WriteTlvLimitedSize([]byte(apkId), 32)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t144.go b/internal/tlv/t144.go
index ab014ac9..0f4f91b6 100644
--- a/internal/tlv/t144.go
+++ b/internal/tlv/t144.go
@@ -12,7 +12,7 @@ func T144(
 ) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x144)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.EncryptAndWrite(tgtgtKey, binary.NewWriterF(func(w *binary.Writer) {
 			w.WriteUInt16(5)
 			w.Write(T109(imei))
@@ -21,6 +21,6 @@ func T144(
 			w.Write(T128(isGuidFromFileNull, isGuidAvailable, isGuidChanged, guidFlag, buildModel, guid, buildBrand))
 			w.Write(T16E(buildModel))
 		}))
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t145.go b/internal/tlv/t145.go
index 9792953f..6f4caf2c 100644
--- a/internal/tlv/t145.go
+++ b/internal/tlv/t145.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T145(guid []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x145)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.Write(guid)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t147.go b/internal/tlv/t147.go
index 4de436ba..e5261cc4 100644
--- a/internal/tlv/t147.go
+++ b/internal/tlv/t147.go
@@ -5,10 +5,10 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T147(appId uint32, apkVersionName, apkSignatureMd5 []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x147)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt32(appId)
 		w.WriteTlvLimitedSize(apkVersionName, 32)
 		w.WriteTlvLimitedSize(apkSignatureMd5, 32)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t154.go b/internal/tlv/t154.go
index 14239670..cf75e02d 100644
--- a/internal/tlv/t154.go
+++ b/internal/tlv/t154.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T154(seq uint16) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x154)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt32(uint32(seq))
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t16.go b/internal/tlv/t16.go
index 0bd5c79c..21a65012 100644
--- a/internal/tlv/t16.go
+++ b/internal/tlv/t16.go
@@ -5,7 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T16(ssoVersion, appId, subAppId uint32, guid, apkId, apkVersionName, apkSign []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x16)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt32(ssoVersion)
 		w.WriteUInt32(appId)
 		w.WriteUInt32(subAppId)
@@ -13,6 +13,6 @@ func T16(ssoVersion, appId, subAppId uint32, guid, apkId, apkVersionName, apkSig
 		w.WriteBytesShort(apkId)
 		w.WriteBytesShort(apkVersionName)
 		w.WriteBytesShort(apkSign)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t166.go b/internal/tlv/t166.go
index d4e50f38..e69880e2 100644
--- a/internal/tlv/t166.go
+++ b/internal/tlv/t166.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T166(imageType byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x166)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteByte(imageType)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t16e.go b/internal/tlv/t16e.go
index e0ea8589..d6e180da 100644
--- a/internal/tlv/t16e.go
+++ b/internal/tlv/t16e.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T16E(buildModel []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x16e)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.Write(buildModel)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t177.go b/internal/tlv/t177.go
index f93c72dd..fe1c96ee 100644
--- a/internal/tlv/t177.go
+++ b/internal/tlv/t177.go
@@ -5,10 +5,10 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T177(buildTime uint32, sdkVersion string) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x177)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteByte(0x01)
 		w.WriteUInt32(buildTime)
 		w.WriteStringShort(sdkVersion)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t17a.go b/internal/tlv/t17a.go
index 90b60bc2..5edcced2 100644
--- a/internal/tlv/t17a.go
+++ b/internal/tlv/t17a.go
@@ -5,8 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T17A(value int32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x17a)
-		pos := w.AllocUInt16Head()
+		w.WriteUInt16(4) // len of uint32
 		w.WriteUInt32(uint32(value))
-		w.WriteUInt16HeadExcludeSelfAt(pos)
 	})
 }
diff --git a/internal/tlv/t17c.go b/internal/tlv/t17c.go
index 3dfd47f1..bd6f493a 100644
--- a/internal/tlv/t17c.go
+++ b/internal/tlv/t17c.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T17C(code string) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x17c)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteStringShort(code)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t18.go b/internal/tlv/t18.go
index 1b33b030..462ab507 100644
--- a/internal/tlv/t18.go
+++ b/internal/tlv/t18.go
@@ -5,7 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T18(appId uint32, uin uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x18)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(1)
 		w.WriteUInt32(1536)
 		w.WriteUInt32(appId)
@@ -13,6 +13,6 @@ func T18(appId uint32, uin uint32) []byte {
 		w.WriteUInt32(uin)
 		w.WriteUInt16(0)
 		w.WriteUInt16(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t187.go b/internal/tlv/t187.go
index de65fe7f..daa7147f 100644
--- a/internal/tlv/t187.go
+++ b/internal/tlv/t187.go
@@ -9,9 +9,9 @@ import (
 func T187(macAddress []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x187)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		h := md5.Sum(macAddress)
 		w.Write(h[:])
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t188.go b/internal/tlv/t188.go
index 6ddb8796..44f394b7 100644
--- a/internal/tlv/t188.go
+++ b/internal/tlv/t188.go
@@ -9,9 +9,9 @@ import (
 func T188(androidId []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x188)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		h := md5.Sum(androidId)
 		w.Write(h[:])
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t191.go b/internal/tlv/t191.go
index a96aff1d..b7c980ad 100644
--- a/internal/tlv/t191.go
+++ b/internal/tlv/t191.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T191(k byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x191)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteByte(k)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t193.go b/internal/tlv/t193.go
index 96ca0bcf..dd42cf87 100644
--- a/internal/tlv/t193.go
+++ b/internal/tlv/t193.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T193(ticket string) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x193)
-		pos := w.AllocUInt16Head()
-		w.Write([]byte(ticket))
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		pos := w.FillUInt16()
+		w.WriteString(ticket)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t194.go b/internal/tlv/t194.go
index 79318eae..4d3d196c 100644
--- a/internal/tlv/t194.go
+++ b/internal/tlv/t194.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T194(imsiMd5 []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x194)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.Write(imsiMd5)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t1b.go b/internal/tlv/t1b.go
index f6b30f70..b00f7fae 100644
--- a/internal/tlv/t1b.go
+++ b/internal/tlv/t1b.go
@@ -5,7 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T1B(micro, version, size, margin, dpi, ecLevel, hint uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x1B)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt32(micro)
 		w.WriteUInt32(version)
 		w.WriteUInt32(size)
@@ -14,6 +14,6 @@ func T1B(micro, version, size, margin, dpi, ecLevel, hint uint32) []byte {
 		w.WriteUInt32(ecLevel)
 		w.WriteUInt32(hint)
 		w.WriteUInt16(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t1d.go b/internal/tlv/t1d.go
index 099b31e5..c123f277 100644
--- a/internal/tlv/t1d.go
+++ b/internal/tlv/t1d.go
@@ -5,12 +5,12 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T1D(miscBitmap uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x1D)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteByte(1)
 		w.WriteUInt32(miscBitmap)
 		w.WriteUInt32(0)
 		w.WriteByte(0)
 		w.WriteUInt32(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t1f.go b/internal/tlv/t1f.go
index 4e671d84..efe79bc1 100644
--- a/internal/tlv/t1f.go
+++ b/internal/tlv/t1f.go
@@ -5,7 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T1F(isRoot bool, osName, osVersion, simOperatorName, apn []byte, networkType uint16) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x1F)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteBool(isRoot)
 		w.WriteBytesShort(osName)
 		w.WriteBytesShort(osVersion)
@@ -13,6 +13,6 @@ func T1F(isRoot bool, osName, osVersion, simOperatorName, apn []byte, networkTyp
 		w.WriteBytesShort(simOperatorName)
 		w.WriteUInt16(0) // w.WriteBytesShort([]byte{})
 		w.WriteBytesShort(apn)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t2.go b/internal/tlv/t2.go
index efa2037a..08a06877 100644
--- a/internal/tlv/t2.go
+++ b/internal/tlv/t2.go
@@ -5,10 +5,10 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T2(result string, sign []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x02)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(0)
 		w.WriteStringShort(result)
 		w.WriteBytesShort(sign)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t202.go b/internal/tlv/t202.go
index ec1c4f69..9b7f07a1 100644
--- a/internal/tlv/t202.go
+++ b/internal/tlv/t202.go
@@ -5,9 +5,9 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T202(wifiBSSID, wifiSSID []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x202)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteTlvLimitedSize(wifiBSSID, 16)
 		w.WriteTlvLimitedSize(wifiSSID, 32)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t35.go b/internal/tlv/t35.go
index 9903096d..1535b5b7 100644
--- a/internal/tlv/t35.go
+++ b/internal/tlv/t35.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T35(productType uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x35)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt32(productType)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t400.go b/internal/tlv/t400.go
index 59173f17..6319ef52 100644
--- a/internal/tlv/t400.go
+++ b/internal/tlv/t400.go
@@ -9,7 +9,7 @@ import (
 func T400(g []byte, uin int64, guid, dpwd []byte, j2, j3 int64, randSeed []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x400)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.EncryptAndWrite(g, binary.NewWriterF(func(w *binary.Writer) {
 			w.WriteUInt16(1) // version
 			w.WriteUInt64(uint64(uin))
@@ -20,6 +20,6 @@ func T400(g []byte, uin int64, guid, dpwd []byte, j2, j3 int64, randSeed []byte)
 			w.WriteUInt32(uint32(time.Now().Unix()))
 			w.Write(randSeed)
 		}))
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t511.go b/internal/tlv/t511.go
index 43609e75..4a4d18b7 100644
--- a/internal/tlv/t511.go
+++ b/internal/tlv/t511.go
@@ -26,7 +26,7 @@ func T511(domains []string) []byte {
 	*/
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x511)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(uint16(len(nonnildomains)))
 		for _, d := range nonnildomains {
 			// 目前的所有调用均不会出现 ()
@@ -59,6 +59,6 @@ func T511(domains []string) []byte {
 				}
 			}*/
 		}
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t516.go b/internal/tlv/t516.go
index fbc2119e..bfba1715 100644
--- a/internal/tlv/t516.go
+++ b/internal/tlv/t516.go
@@ -5,8 +5,7 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T516() []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x516)
-		pos := w.AllocUInt16Head()
+		w.WriteUInt16(4) // len of uint32
 		w.WriteUInt32(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
 	})
 }
diff --git a/internal/tlv/t521.go b/internal/tlv/t521.go
index 9ae32d2a..f5e021a9 100644
--- a/internal/tlv/t521.go
+++ b/internal/tlv/t521.go
@@ -5,9 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T521(i uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x521)
-		pos := w.AllocUInt16Head()
+		w.WriteUInt16(4 + 2)
 		w.WriteUInt32(i)
 		w.WriteUInt16(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
 	})
 }
diff --git a/internal/tlv/t525.go b/internal/tlv/t525.go
index 0b843f0a..ef80e37c 100644
--- a/internal/tlv/t525.go
+++ b/internal/tlv/t525.go
@@ -5,9 +5,9 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T525(t536 []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x525)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(1)
 		w.Write(t536)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t52d.go b/internal/tlv/t52d.go
index 16273e8f..0ad17be0 100644
--- a/internal/tlv/t52d.go
+++ b/internal/tlv/t52d.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T52D(devInfo []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x52d)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.Write(devInfo)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t536.go b/internal/tlv/t536.go
index c6f5f290..4096a83e 100644
--- a/internal/tlv/t536.go
+++ b/internal/tlv/t536.go
@@ -5,8 +5,8 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T536(loginExtraData []byte) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x536)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.Write(loginExtraData)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }
diff --git a/internal/tlv/t8.go b/internal/tlv/t8.go
index b2b79337..851f794b 100644
--- a/internal/tlv/t8.go
+++ b/internal/tlv/t8.go
@@ -5,10 +5,10 @@ import "github.com/Mrs4s/MiraiGo/binary"
 func T8(localId uint32) []byte {
 	return binary.NewWriterF(func(w *binary.Writer) {
 		w.WriteUInt16(0x8)
-		pos := w.AllocUInt16Head()
+		pos := w.FillUInt16()
 		w.WriteUInt16(0)
 		w.WriteUInt32(localId)
 		w.WriteUInt16(0)
-		w.WriteUInt16HeadExcludeSelfAt(pos)
+		w.WriteUInt16At(pos, uint16(w.Len()-4))
 	})
 }