Files
tun2socks/proxy/exception/udp.go
2019-08-12 18:48:08 +08:00

110 lines
2.4 KiB
Go

package exception
import (
"net"
"strconv"
"sync"
"time"
"github.com/xjasonlyu/tun2socks/common/log"
"github.com/xjasonlyu/tun2socks/common/lsof"
"github.com/xjasonlyu/tun2socks/common/pool"
"github.com/xjasonlyu/tun2socks/core"
)
type udpHandler struct {
timeout time.Duration
exceptionConnMap sync.Map
exceptionApps []string
sendThrough net.Addr
proxyHandler core.UDPConnHandler
}
func (h *udpHandler) isExceptionApp(name string) bool {
for _, app := range h.exceptionApps {
if name == app {
return true
}
}
return false
}
func NewUDPHandler(proxyHandler core.UDPConnHandler, exceptionApps []string, sendThrough net.Addr, timeout time.Duration) core.UDPConnHandler {
return &udpHandler{
proxyHandler: proxyHandler,
exceptionApps: exceptionApps,
sendThrough: sendThrough,
timeout: timeout,
}
}
func (h *udpHandler) handleInput(conn core.UDPConn, pc *net.UDPConn) {
buf := pool.BufPool.Get().([]byte)
defer func() {
h.Close(conn)
pool.BufPool.Put(buf[:cap(buf)])
}()
for {
pc.SetDeadline(time.Now().Add(h.timeout))
n, addr, err := pc.ReadFromUDP(buf)
if err != nil {
return
}
if _, err := conn.WriteFrom(buf[:n], addr); err != nil {
return
}
}
}
func (h *udpHandler) Connect(conn core.UDPConn, target *net.UDPAddr) error {
localHost, localPortStr, _ := net.SplitHostPort(conn.LocalAddr().String())
localPortInt, _ := strconv.Atoi(localPortStr)
cmd, err := lsof.GetCommandNameBySocket("udp", localHost, uint16(localPortInt))
if err != nil {
cmd = "N/A"
}
if h.isExceptionApp(cmd) {
bindAddr, _ := net.ResolveUDPAddr("udp", h.sendThrough.String())
pc, err := net.ListenUDP("udp", bindAddr)
if err != nil {
return err
}
h.exceptionConnMap.Store(conn, pc)
go h.handleInput(conn, pc)
log.Access(cmd, "direct", target.Network(), conn.LocalAddr().String(), target.String())
return nil
} else {
return h.proxyHandler.Connect(conn, target)
}
}
func (h *udpHandler) ReceiveTo(conn core.UDPConn, data []byte, addr *net.UDPAddr) error {
if pc, ok := h.exceptionConnMap.Load(conn); ok {
_, err := pc.(*net.UDPConn).WriteTo(data, addr)
if err != nil {
return err
}
return nil
} else {
return h.proxyHandler.ReceiveTo(conn, data, addr)
}
}
func (h *udpHandler) Close(conn core.UDPConn) {
conn.Close()
if pc, ok := h.exceptionConnMap.Load(conn); ok {
pc.(*net.UDPConn).Close()
h.exceptionConnMap.Delete(conn)
}
}