repository cleanup

network/crypt_packet.go

@@ -0,0 +1,90 @@
+package network
+
+import (
+	"bytes"
+	"encoding/binary"
+)
+
+const (
+	// CryptPacketHeaderLength represents the byte-length of
+	// an encrypted packet header.
+	CryptPacketHeaderLength = 14
+)
+
+// CryptPacketHeader represents the parsed information of an encrypted packet header.
+type CryptPacketHeader struct {
+	Pf0                     byte
+	KeyRotDelta             byte
+	PacketNum               uint16
+	DataSize                uint16
+	PrevPacketCombinedCheck uint16
+	Check0                  uint16
+	Check1                  uint16
+	Check2                  uint16
+}
+
+// NewCryptPacketHeader parses raw bytes into a CryptPacketHeader
+func NewCryptPacketHeader(data []byte) (*CryptPacketHeader, error) {
+	var c = CryptPacketHeader{}
+
+	r := bytes.NewReader(data)
+
+	var err error
+	err = binary.Read(r, binary.BigEndian, &c.Pf0)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.KeyRotDelta)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.PacketNum)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.DataSize)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.PrevPacketCombinedCheck)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.Check0)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.Check1)
+	if err != nil {
+		return nil, err
+	}
+	err = binary.Read(r, binary.BigEndian, &c.Check2)
+	if err != nil {
+		return nil, err
+	}
+
+	return &c, nil
+}
+
+// Encode encodes the CryptPacketHeader into raw bytes.
+func (c *CryptPacketHeader) Encode() ([]byte, error) {
+	buf := bytes.NewBuffer([]byte{})
+	var data = []interface{}{
+		c.Pf0,
+		c.KeyRotDelta,
+		c.PacketNum,
+		c.DataSize,
+		c.PrevPacketCombinedCheck,
+		c.Check0,
+		c.Check1,
+		c.Check2,
+	}
+	for _, v := range data {
+		err := binary.Write(buf, binary.BigEndian, v)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return buf.Bytes(), nil
+}