func (c *Client) Send(data []byte, params ...bool) error {
var doChecksum, doBlowfish bool = true, true
// Should we skip the checksum?
if len(params) >= 1 && params[0] == false {
doChecksum = false
}
// Should we skip the blowfish encryption?
if len(params) >= 2 && params[1] == false {
doBlowfish = false
}
if doChecksum == true {
// Add 4 empty bytes for the checksum new( new(
data = append(data, []byte{0x00, 0x00, 0x00, 0x00}...)
// Add blowfish padding
missing := len(data) % 8
if missing != 0 {
for i := missing; i < 8; i++ {
data = append(data, byte(0x00))
}
}
// Finally do the checksum
crypt.Checksum(data)
}
if doBlowfish == true {
var err error
data, err = crypt.BlowfishEncrypt(data, []byte("[;'.]94-31==-%&@!^+]\000"))
if err != nil {
return err
}
}
// Calculate the packet length
length := uint16(len(data) + 2)
// Put everything together
buffer := packets.NewBuffer()
buffer.WriteUInt16(length)
buffer.Write(data)
_, err := c.Socket.Write(buffer.Bytes())
if err != nil {
return errors.New("The packet couldn't be sent.")
}
return nil
}
func (c *Client) Receive() (opcode byte, data []byte, e error) {
// Read the first two bytes to define the packet size
header := make([]byte, 2)
n, err := c.Socket.Read(header)
if n != 2 || err != nil {
return 0x00, nil, errors.New("An error occured while reading the packet header.")
}
// Calculate the packet size
size := 0
size = size + int(header[0])
size = size + int(header[1])*256
// Allocate the appropriate size for our data (size - 2 bytes used for the length
data = make([]byte, size-2)
// Read the encrypted part of the packet
n, err = c.Socket.Read(data)
if n != size-2 || err != nil {
return 0x00, nil, errors.New("An error occured while reading the packet data.")
}
// Print the raw packet
fmt.Printf("Raw packet : %X%X\n", header, data)
// Decrypt the packet data using the blowfish key
data, err = crypt.BlowfishDecrypt(data, []byte("[;'.]94-31==-%&@!^+]\000"))
if err != nil {
return 0x00, nil, errors.New("An error occured while decrypting the packet data.")
}
// Verify our checksum...
if check := crypt.Checksum(data); check {
fmt.Printf("Decrypted packet content : %X\n", data)
fmt.Println("Packet checksum ok")
} else {
return 0x00, nil, errors.New("The packet checksum doesn't look right...")
}
// Extract the op code
opcode = data[0]
data = data[1:]
e = nil
return
}