clash/listener/tproxy/udp.go
2023-02-18 13:16:07 +08:00

106 lines
2.1 KiB
Go

package tproxy
import (
"net"
"net/netip"
"github.com/Dreamacro/clash/adapter/inbound"
"github.com/Dreamacro/clash/common/pool"
C "github.com/Dreamacro/clash/constant"
"github.com/Dreamacro/clash/transport/socks5"
)
type UDPListener struct {
packetConn net.PacketConn
addr string
closed bool
}
// RawAddress implements C.Listener
func (l *UDPListener) RawAddress() string {
return l.addr
}
// Address implements C.Listener
func (l *UDPListener) Address() string {
return l.packetConn.LocalAddr().String()
}
// Close implements C.Listener
func (l *UDPListener) Close() error {
l.closed = true
return l.packetConn.Close()
}
func NewUDP(addr string, in chan<- C.PacketAdapter, natTable C.NatTable, additions ...inbound.Addition) (*UDPListener, error) {
if len(additions) == 0 {
additions = []inbound.Addition{
inbound.WithInName("DEFAULT-TPROXY"),
inbound.WithSpecialRules(""),
}
}
l, err := net.ListenPacket("udp", addr)
if err != nil {
return nil, err
}
rl := &UDPListener{
packetConn: l,
addr: addr,
}
c := l.(*net.UDPConn)
rc, err := c.SyscallConn()
if err != nil {
return nil, err
}
err = setsockopt(rc, addr)
if err != nil {
return nil, err
}
go func() {
oob := make([]byte, 1024)
for {
buf := pool.Get(pool.UDPBufferSize)
n, oobn, _, lAddr, err := c.ReadMsgUDPAddrPort(buf, oob)
if err != nil {
pool.Put(buf)
if rl.closed {
break
}
continue
}
rAddr, err := getOrigDst(oob[:oobn])
if err != nil {
continue
}
if rAddr.Addr().Is4() {
// try to unmap 4in6 address
lAddr = netip.AddrPortFrom(lAddr.Addr().Unmap(), lAddr.Port())
}
handlePacketConn(l, in, natTable, buf[:n], lAddr, rAddr, additions...)
}
}()
return rl, nil
}
func handlePacketConn(pc net.PacketConn, in chan<- C.PacketAdapter, natTable C.NatTable, buf []byte, lAddr, rAddr netip.AddrPort, additions ...inbound.Addition) {
target := socks5.AddrFromStdAddrPort(rAddr)
pkt := &packet{
pc: pc,
lAddr: lAddr,
buf: buf,
in: in,
natTable: natTable,
}
select {
case in <- inbound.NewPacket(target, pkt, C.TPROXY, additions...):
default:
}
}