diff --git a/binary/reader.go b/binary/reader.go
index 3fcaa701..f5ff0bb3 100644
--- a/binary/reader.go
+++ b/binary/reader.go
@@ -17,8 +17,6 @@ type NetworkReader struct {
 	conn net.Conn
 }
 
-type TlvMap map[uint16][]byte
-
 // --- ByteStream reader ---
 
 func NewReader(data []byte) *Reader {
@@ -92,33 +90,6 @@ func (r *Reader) ReadAvailable() []byte {
 	return r.ReadBytes(r.buf.Len())
 }
 
-func (r *Reader) ReadTlvMap(tagSize int) (m TlvMap) {
-	defer func() {
-		if r := recover(); r != nil {
-			// TODO: error
-		}
-	}()
-	m = make(map[uint16][]byte)
-	for {
-		if r.Len() < tagSize {
-			return m
-		}
-		var k uint16
-		switch tagSize {
-		case 1:
-			k = uint16(r.ReadByte())
-		case 2:
-			k = r.ReadUInt16()
-		case 4:
-			k = uint16(r.ReadInt32())
-		}
-		if k == 255 {
-			return m
-		}
-		m[k] = r.ReadBytes(int(r.ReadUInt16()))
-	}
-}
-
 func (r *Reader) Len() int {
 	return r.buf.Len()
 }
@@ -127,11 +98,6 @@ func (r *Reader) Index() int64 {
 	return r.buf.Size()
 }
 
-func (tlv TlvMap) Exists(key uint16) bool {
-	_, ok := tlv[key]
-	return ok
-}
-
 // --- Network reader ---
 
 func NewNetworkReader(conn net.Conn) *NetworkReader {
diff --git a/client/decoders.go b/client/decoders.go
index 55684b46..0289ae83 100644
--- a/client/decoders.go
+++ b/client/decoders.go
@@ -15,6 +15,7 @@ import (
 	"github.com/Mrs4s/MiraiGo/binary/jce"
 	"github.com/Mrs4s/MiraiGo/client/internal/auth"
 	"github.com/Mrs4s/MiraiGo/client/internal/network"
+	"github.com/Mrs4s/MiraiGo/client/internal/tlv"
 	"github.com/Mrs4s/MiraiGo/client/pb"
 	"github.com/Mrs4s/MiraiGo/client/pb/cmd0x352"
 	"github.com/Mrs4s/MiraiGo/client/pb/cmd0x6ff"
@@ -37,7 +38,10 @@ func decodeLoginResponse(c *QQClient, _ *network.IncomingPacketInfo, payload []b
 	reader.ReadUInt16() // sub command
 	t := reader.ReadByte()
 	reader.ReadUInt16()
-	m := reader.ReadTlvMap(2)
+	m, err := tlv.NewDecoder(2, 2).DecodeRecordMap(reader.ReadAvailable())
+	if err != nil {
+		return nil, err
+	}
 	if m.Exists(0x402) {
 		c.sig.Dpwd = []byte(utils.RandomString(16))
 		c.sig.T402 = m[0x402]
@@ -45,9 +49,7 @@ func decodeLoginResponse(c *QQClient, _ *network.IncomingPacketInfo, payload []b
 		c.sig.G = h[:]
 	}
 	if m.Exists(0x546) {
-		c.debug("pow start")
 		c.sig.T547 = auth.CalcPow(m[0x546])
-		c.debug("pow end")
 	}
 	if t == 0 { // login success
 		// if t150, ok := m[0x150]; ok {
@@ -208,7 +210,10 @@ func decodeExchangeEmpResponse(c *QQClient, _ *network.IncomingPacketInfo, paylo
 	cmd := reader.ReadUInt16()
 	t := reader.ReadByte()
 	reader.ReadUInt16()
-	m := reader.ReadTlvMap(2)
+	m, err := tlv.NewDecoder(2, 2).DecodeRecordMap(reader.ReadAvailable())
+	if err != nil {
+		return nil, err
+	}
 	if t != 0 {
 		return nil, errors.Errorf("exchange_emp failed: %v", t)
 	}
@@ -248,7 +253,10 @@ func decodeTransEmpResponse(c *QQClient, _ *network.IncomingPacketInfo, payload
 		}
 		sig := body.ReadBytesShort()
 		body.ReadUInt16()
-		m := body.ReadTlvMap(2)
+		m, err := tlv.NewDecoder(2, 2).DecodeRecordMap(reader.ReadAvailable())
+		if err != nil {
+			return nil, err
+		}
 		if m.Exists(0x17) {
 			return &QRCodeLoginResponse{
 				State:     QRCodeImageFetch,
@@ -291,7 +299,10 @@ func decodeTransEmpResponse(c *QQClient, _ *network.IncomingPacketInfo, payload
 		c.highwaySession.Uin = strconv.FormatInt(c.Uin, 10)
 		body.ReadInt32() // sig create time
 		body.ReadUInt16()
-		m := body.ReadTlvMap(2)
+		m, err := tlv.NewDecoder(2, 2).DecodeRecordMap(reader.ReadAvailable())
+		if err != nil {
+			return nil, err
+		}
 		if !m.Exists(0x18) || !m.Exists(0x1e) || !m.Exists(0x19) {
 			return nil, errors.New("wtlogin.trans_emp sub cmd 0x12 error: tlv error")
 		}
@@ -447,6 +458,15 @@ func decodeSummaryCardResponse(_ *QQClient, _ *network.IncomingPacketInfo, paylo
 			info.VipLevel = fmt.Sprintf("svip%d", v3.Level)
 		}
 	}
+
+	richSign := rsp.ReadBytes(32)
+	records, _ := tlv.NewDecoder(1, 1).Decode(richSign)
+	for _, r := range records {
+		if r.Tag == 3 {
+			info.Sign = string(r.Value)
+		}
+	}
+
 	info.LoginDays = rsp.ReadInt64(36)
 	services := rsp.ReadByteArrArr(46)
 	readService := func(buf []byte) (*profilecard.BusiComm, []byte) {
diff --git a/client/internal/tlv/decoder.go b/client/internal/tlv/decoder.go
new file mode 100644
index 00000000..82524971
--- /dev/null
+++ b/client/internal/tlv/decoder.go
@@ -0,0 +1,107 @@
+package tlv
+
+import (
+	"encoding/binary"
+
+	"github.com/pkg/errors"
+)
+
+// Record represents a Tag-Length-Value record.
+type Record struct {
+	Tag    int
+	Length int
+	Value  []byte
+}
+
+type RecordMap map[int][]byte
+
+func (rm RecordMap) Exists(key int) bool {
+	_, ok := rm[key]
+	return ok
+}
+
+var (
+	ErrMessageTooShort = errors.New("tlv: message too short")
+)
+
+// Decoder is a configurable TLV decoder.
+type Decoder struct {
+	tagSize  uint8
+	lenSize  uint8
+	headSize uint8
+}
+
+func NewDecoder(tagSize, lenSize uint8) *Decoder {
+	check := func(t string, s uint8) {
+		switch s {
+		case 1, 2, 4:
+			// ok
+		default:
+			panic("invalid " + t)
+		}
+	}
+	check("tag size", tagSize)
+	check("len size", lenSize)
+
+	return &Decoder{tagSize: tagSize, lenSize: lenSize, headSize: tagSize + lenSize}
+}
+
+func (d *Decoder) decodeRecord(data []byte) (r Record, err error) {
+	tagSize := d.tagSize
+	lenSize := d.lenSize
+	headSize := int(tagSize + lenSize)
+	if len(data) < headSize {
+		err = ErrMessageTooShort
+		return
+	}
+
+	r.Tag = d.read(tagSize, data)
+	r.Length = d.read(lenSize, data[tagSize:])
+
+	if len(data) < headSize+r.Length {
+		err = ErrMessageTooShort
+		return
+	}
+	r.Value = data[headSize : headSize+r.Length : headSize+r.Length]
+	return
+}
+
+func (d *Decoder) read(size uint8, data []byte) int {
+	switch size {
+	case 1:
+		return int(data[0])
+	case 2:
+		return int(binary.BigEndian.Uint16(data))
+	case 4:
+		return int(binary.BigEndian.Uint32(data))
+	default:
+		panic("invalid size")
+	}
+}
+
+func (d *Decoder) Decode(data []byte) ([]Record, error) {
+	var records []Record
+	for len(data) > 0 {
+		r, err := d.decodeRecord(data)
+		if err != nil {
+			return nil, err
+		}
+		records = append(records, r)
+		data = data[int(d.headSize)+r.Length:]
+	}
+	return records, nil
+}
+
+func (d *Decoder) DecodeRecordMap(data []byte) (RecordMap, error) {
+	records, err := d.Decode(data)
+	if err != nil {
+		return nil, err
+	}
+
+	rm := make(RecordMap, len(records))
+	for _, record := range records {
+		rm[record.Tag] = record.Value
+	}
+
+	return rm, nil
+}
diff --git a/client/tlv_decoders.go b/client/tlv_decoders.go
index 030e7ee0..94eba0fb 100644
--- a/client/tlv_decoders.go
+++ b/client/tlv_decoders.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"time"
 
+	"github.com/Mrs4s/MiraiGo/client/internal/tlv"
 	"github.com/Mrs4s/MiraiGo/utils"
 
 	"github.com/Mrs4s/MiraiGo/binary"
@@ -25,9 +26,7 @@ func (c *QQClient) decodeT161(data []byte) {
 
 func (c *QQClient) decodeT119(data, ek []byte) {
 	tea := binary.NewTeaCipher(ek)
-	reader := binary.NewReader(tea.Decrypt(data))
-	reader.ReadBytes(2)
-	m := reader.ReadTlvMap(2)
+	m, _ := tlv.NewDecoder(2, 2).DecodeRecordMap(tea.Decrypt(data)[2:])
 	if t130, ok := m[0x130]; ok {
 		c.decodeT130(t130)
 	}
@@ -133,9 +132,7 @@ func (c *QQClient) decodeT119(data, ek []byte) {
 // wtlogin.exchange_emp
 func (c *QQClient) decodeT119R(data []byte) {
 	tea := binary.NewTeaCipher(c.deviceInfo.TgtgtKey)
-	reader := binary.NewReader(tea.Decrypt(data))
-	reader.ReadBytes(2)
-	m := reader.ReadTlvMap(2)
+	m, _ := tlv.NewDecoder(2, 2).DecodeRecordMap(tea.Decrypt(data)[2:])
 	if t120, ok := m[0x120]; ok {
 		c.sig.SKey = t120
 		c.sig.SKeyExpiredTime = time.Now().Unix() + 21600
@@ -223,8 +220,7 @@ func readT512(data []byte) (psKeyMap map[string][]byte, pt4TokenMap map[string][
 }
 
 func readT531(data []byte) (a1, noPicSig []byte) {
-	reader := binary.NewReader(data)
-	m := reader.ReadTlvMap(2)
+	m, _ := tlv.NewDecoder(2, 2).DecodeRecordMap(data)
 	if m.Exists(0x103) && m.Exists(0x16a) && m.Exists(0x113) && m.Exists(0x10c) {
 		a1 = append(m[0x106], m[0x10c]...)
 		noPicSig = m[0x16a]
diff --git a/go.sum b/go.sum
index fa3c6218..6dce1d77 100644
--- a/go.sum
+++ b/go.sum
@@ -7,6 +7,11 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/fumiama/imgsz v0.0.2 h1:fAkC0FnIscdKOXwAxlyw3EUba5NzxZdSxGaq3Uyfxak=
 github.com/fumiama/imgsz v0.0.2/go.mod h1:dR71mI3I2O5u6+PCpd47M9TZptzP+39tRBcbdIkoqM4=
+github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
+github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
+github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
+github.com/kr/text v0.1.0 h1:45sCR5RtlFHMR4UwH9sdQ5TC8v0qDQCHnXt+kaKSTVE=
+github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
 github.com/pierrec/lz4/v4 v4.1.15 h1:MO0/ucJhngq7299dKLwIMtgTfbkoSPF6AoMYDd8Q4q0=
 github.com/pierrec/lz4/v4 v4.1.15/go.mod h1:gZWDp/Ze/IJXGXf23ltt2EXimqmTUXEy0GFuRQyBid4=
 github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
@@ -26,8 +31,9 @@ github.com/tidwall/pretty v1.2.0 h1:RWIZEg2iJ8/g6fDDYzMpobmaoGh5OLl4AXtGUGPcqCs=
 github.com/tidwall/pretty v1.2.0/go.mod h1:ITEVvHYasfjBbM0u2Pg8T2nJnzm8xPwvNhhsoaGGjNU=
 golang.org/x/sync v0.0.0-20220819030929-7fc1605a5dde h1:ejfdSekXMDxDLbRrJMwUk6KnSLZ2McaUCVcIKM+N6jc=
 golang.org/x/sync v0.0.0-20220819030929-7fc1605a5dde/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=