84 lines
1.5 KiB
Go
84 lines
1.5 KiB
Go
package socks5
|
|
|
|
import (
|
|
"bytes"
|
|
"io"
|
|
)
|
|
|
|
// Datagram is the datagram packet
|
|
type Datagram struct {
|
|
ATYP ATYP
|
|
DstAddr []byte
|
|
DstPort []byte
|
|
Data []byte
|
|
}
|
|
|
|
// NewDatagram creates new datagram packet
|
|
func NewDatagram(atyp ATYP, host []byte, port []byte, data []byte) *Datagram {
|
|
return &Datagram{
|
|
ATYP: atyp,
|
|
DstAddr: host,
|
|
DstPort: port,
|
|
Data: data,
|
|
}
|
|
}
|
|
|
|
// NewDatagramFrom reads datagram packet from reader
|
|
func NewDatagramFrom(r io.Reader) (*Datagram, error) {
|
|
buf := make([]byte, 4)
|
|
if _, err := io.ReadFull(r, buf); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
if !bytes.Equal([]byte{Reserved, Reserved}, buf[:2]) {
|
|
return nil, ErrBadDatagram
|
|
}
|
|
|
|
if buf[2] != DatagramStandalone {
|
|
return nil, ErrFragmentedDatagram
|
|
}
|
|
|
|
addr, err := ReadAddress(r, ATYP(buf[3]))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
port := make([]byte, 2)
|
|
if _, err := io.ReadFull(r, port); err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
data, err := io.ReadAll(r)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
datagram := &Datagram{
|
|
ATYP: ATYP(buf[3]),
|
|
DstAddr: addr,
|
|
DstPort: port,
|
|
Data: data,
|
|
}
|
|
|
|
return datagram, nil
|
|
}
|
|
|
|
// WriteTo writes datagram packet
|
|
func (s *Datagram) WriteTo(w io.Writer) (int64, error) {
|
|
n, err := w.Write(s.Bytes())
|
|
if err != nil {
|
|
return int64(n), err
|
|
}
|
|
|
|
return int64(n), nil
|
|
}
|
|
|
|
func (s *Datagram) Bytes() []byte {
|
|
buf := bytes.NewBuffer([]byte{Reserved, Reserved, DatagramStandalone, byte(s.ATYP)})
|
|
buf.Write(s.DstAddr)
|
|
buf.Write(s.DstPort)
|
|
buf.Write(s.Data)
|
|
|
|
return buf.Bytes()
|
|
}
|