173 lines
3.1 KiB
Go
173 lines
3.1 KiB
Go
package socks
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import (
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"bytes"
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"net"
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"github.com/go-gost/gosocks5"
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"github.com/go-gost/gost/pkg/common/bufpool"
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)
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type udpTunConn struct {
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net.Conn
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taddr net.Addr
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}
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func UDPTunClientConn(c net.Conn, targetAddr net.Addr) net.Conn {
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return &udpTunConn{
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Conn: c,
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taddr: targetAddr,
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}
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}
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func UDPTunClientPacketConn(c net.Conn) net.PacketConn {
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return &udpTunConn{
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Conn: c,
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}
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}
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func UDPTunServerConn(c net.Conn) net.PacketConn {
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return &udpTunConn{
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Conn: c,
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}
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}
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func (c *udpTunConn) ReadFrom(b []byte) (n int, addr net.Addr, err error) {
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socksAddr := gosocks5.Addr{}
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header := gosocks5.UDPHeader{
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Addr: &socksAddr,
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}
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dgram := gosocks5.UDPDatagram{
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Header: &header,
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Data: b,
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}
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_, err = dgram.ReadFrom(c.Conn)
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if err != nil {
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return
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}
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n = len(dgram.Data)
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if n > len(b) {
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n = copy(b, dgram.Data)
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}
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addr, err = net.ResolveUDPAddr("udp", socksAddr.String())
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return
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}
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func (c *udpTunConn) Read(b []byte) (n int, err error) {
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n, _, err = c.ReadFrom(b)
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return
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}
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func (c *udpTunConn) WriteTo(b []byte, addr net.Addr) (n int, err error) {
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socksAddr := gosocks5.Addr{}
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if err = socksAddr.ParseFrom(addr.String()); err != nil {
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return
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}
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header := gosocks5.UDPHeader{
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Addr: &socksAddr,
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}
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dgram := gosocks5.UDPDatagram{
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Header: &header,
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Data: b,
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}
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dgram.Header.Rsv = uint16(len(dgram.Data))
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dgram.Header.Frag = 0xff // UDP tun relay flag, used by shadowsocks
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_, err = dgram.WriteTo(c.Conn)
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n = len(b)
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return
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}
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func (c *udpTunConn) Write(b []byte) (n int, err error) {
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return c.WriteTo(b, c.taddr)
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}
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var (
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DefaultBufferSize = 4096
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)
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type udpConn struct {
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net.PacketConn
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raddr net.Addr
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taddr net.Addr
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bufferSize int
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}
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func UDPConn(c net.PacketConn, bufferSize int) net.PacketConn {
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return &udpConn{
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PacketConn: c,
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bufferSize: bufferSize,
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}
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}
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// ReadFrom reads an UDP datagram.
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// NOTE: for server side,
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// the returned addr is the target address the client want to relay to.
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func (c *udpConn) ReadFrom(b []byte) (n int, addr net.Addr, err error) {
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rbuf := bufpool.Get(c.bufferSize)
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defer bufpool.Put(rbuf)
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n, c.raddr, err = c.PacketConn.ReadFrom(rbuf)
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if err != nil {
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return
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}
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socksAddr := gosocks5.Addr{}
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header := gosocks5.UDPHeader{
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Addr: &socksAddr,
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}
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hlen, err := header.ReadFrom(bytes.NewReader(rbuf[:n]))
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if err != nil {
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return
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}
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n = copy(b, rbuf[hlen:n])
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addr, err = net.ResolveUDPAddr("udp", socksAddr.String())
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return
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}
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func (c *udpConn) Read(b []byte) (n int, err error) {
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n, _, err = c.ReadFrom(b)
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return
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}
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func (c *udpConn) WriteTo(b []byte, addr net.Addr) (n int, err error) {
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wbuf := bufpool.Get(c.bufferSize)
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defer bufpool.Put(wbuf)
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socksAddr := gosocks5.Addr{}
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if err = socksAddr.ParseFrom(addr.String()); err != nil {
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return
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}
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header := gosocks5.UDPHeader{
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Addr: &socksAddr,
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}
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dgram := gosocks5.UDPDatagram{
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Header: &header,
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Data: b,
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}
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buf := bytes.NewBuffer(wbuf[:0])
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_, err = dgram.WriteTo(buf)
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if err != nil {
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return
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}
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_, err = c.PacketConn.WriteTo(buf.Bytes(), c.raddr)
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n = len(b)
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return
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}
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func (c *udpConn) Write(b []byte) (n int, err error) {
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return c.WriteTo(b, c.taddr)
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}
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func (c *udpConn) RemoteAddr() net.Addr {
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return c.raddr
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}
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