729 lines
16 KiB
Go
729 lines
16 KiB
Go
package server
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import (
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"bytes"
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"cert"
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"crypto/tls"
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"encoding/json"
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"fmt"
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"hash/crc32"
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"io"
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"net"
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"net/url"
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"rakshasa/aes"
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"rakshasa/common"
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"runtime/debug"
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"strconv"
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"strings"
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"sync"
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"sync/atomic"
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"time"
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)
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var (
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bufPool = &sync.Pool{
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New: func() interface{} {
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return &bytes.Buffer{}
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},
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}
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closeChan = make(chan *bytes.Buffer, 1) //用于接收已关闭消息的黑洞chan
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)
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// 节点的连接，包含listen来的和主动connect的
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type Conn struct {
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closeTag int32
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node *node
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nodeaddr string
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//key string
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remoteAddr string
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inChan chan func()
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OutChan chan []byte
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close chan string
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isClient bool
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nodeConn *tls.Conn
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regResult chan RegMsg
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}
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type serverListen struct {
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close int32
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node *node
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listen net.Listener
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isSocks5 bool
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socks5Replay []byte
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replayid uint32
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id uint32
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connMap sync.Map
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randkey []byte
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}
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type serverConnect struct {
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close int32
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id uint32
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windowsSize int64
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conn net.Conn
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node *node
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address string
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write chan *bytes.Buffer
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wait chan int
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closeReason string
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randkey []byte
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}
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// 中转与最终出口
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func StartServer(addr string) error {
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config := cert.Tlsconfig.Clone()
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fmt.Println("start on ", addr)
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l, err := tls.Listen("tcp", addr, config)
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if err != nil {
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return fmt.Errorf("server start fail %v", err)
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}
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currentNode.listen = l
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go func() {
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for {
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conn, err := l.Accept()
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if err != nil {
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if err.(*net.OpError).Err == net.ErrClosed {
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return
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}
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continue
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}
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//封装一个符合common.server接口的server
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c := &Conn{
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nodeConn: conn.(*tls.Conn),
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remoteAddr: conn.RemoteAddr().String(),
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}
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connMap.Store(c.remoteAddr, conn)
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go c.handlerNodeRead()
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go c.handle()
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}
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}()
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return nil
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}
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func init() {
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go func() {
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for b := range closeChan {
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b.Reset()
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bufPool.Put(b)
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}
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}()
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}
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func (conn *serverConnect) Close(reason string) {
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if atomic.CompareAndSwapInt32(&conn.close, 0, 1) {
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go func() {
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if conn.conn != nil {
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conn.conn.Close()
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}
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//fmt.Println(conn.fd, reason)
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conn.node.connMap.Delete(conn.id)
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conn.closeReason = reason
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conn.node.listenMap.Range(func(key, value interface{}) bool {
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value.(*serverListen).connMap.Delete(conn.id)
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return true
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})
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if reason != remoteClose {
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conn.node.Write(common.CMD_DELETE_CONNID, conn.id, nil)
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}
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select {
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case conn.wait <- common.CONN_STATUS_CLOSE:
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case <-time.After(time.Second * 10):
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}
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conn.write <- nil
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conn.write = closeChan
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}()
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}
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}
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func (c *Conn) Close(reason string) {
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c.close <- reason
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}
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func (conn *serverConnect) handTcpReceive() {
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go func() {
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for b := range conn.write {
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if b == nil {
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conn.write = closeChan
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return
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}
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if _, err := conn.conn.Write(b.Bytes()); err != nil {
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conn.Close(err.Error())
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}
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b.Reset()
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bufPool.Put(b)
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}
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}()
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var err error
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var n int
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defer func() {
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if err != nil {
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conn.Close(conn.address + " 读取出错" + err.Error())
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} else {
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conn.Close(conn.address + " read异常关闭")
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}
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}()
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buf := make([]byte, common.MAX_PLAINTEXT)
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for conn.close == 0 {
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conn.conn.SetReadDeadline(time.Now().Add(common.WRITE_DEADLINE))
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n, err = conn.conn.Read(buf)
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if err != nil {
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if atomic.LoadInt32(&conn.close) == 0 {
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if e := err.Error(); !strings.Contains(e, ": i/o timeout") {
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return
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}
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continue
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} else {
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return
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}
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}
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data := make([]byte, n)
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copy(data, buf)
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if common.Debug {
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fmt.Println("发送", crc32.ChecksumIEEE(data), n)
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}
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conn.node.Write(common.CMD_CONN_MSG, conn.id, data)
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atomic.AddInt64(&conn.windowsSize, -1*int64(n))
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for atomic.LoadInt64(&conn.windowsSize) <= 0 && conn.close == 0 {
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select {
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case flag := <-conn.wait:
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if flag == common.CONN_STATUS_CLOSE {
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return
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}
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case <-time.After(time.Second):
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}
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}
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}
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}
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func (conn *serverConnect) Write(data []byte) {
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data = data[1:]
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windows_update_size := int64(data[0]) | int64(data[1])<<8 | int64(data[2])<<16 | int64(data[3])<<24 | int64(data[4])<<32 | int64(data[5])<<40 | int64(data[6])<<48 | int64(data[7])<<56
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if windows_update_size != 0 {
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old := atomic.AddInt64(&conn.windowsSize, windows_update_size) - windows_update_size
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if old < 0 {
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go func() {
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select {
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case conn.wait <- common.CONN_STATUS_OK:
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case <-time.After(time.Second):
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}
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}()
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}
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}
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if common.Debug {
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fmt.Println("收到", crc32.ChecksumIEEE(data[8:]), len(data[8:]))
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}
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b := bufPool.Get().(*bytes.Buffer)
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b.Reset()
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b.Write(data[8:])
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conn.write <- b
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}
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func (conn *serverConnect) handUdpReceive() {
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var err error
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var n int
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defer func() {
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if err != nil {
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conn.Close(conn.address + " 网站读取出错" + err.Error())
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} else {
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conn.Close(conn.address + " read异常关闭")
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}
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}()
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buf := make([]byte, common.MAX_PLAINTEXT)
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for conn.close == 0 {
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conn.conn.SetReadDeadline(time.Now().Add(common.WRITE_DEADLINE))
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n, err = conn.conn.Read(buf)
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if err != nil {
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if atomic.LoadInt32(&conn.close) == 0 {
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if e := err.Error(); !strings.Contains(e, ": i/o timeout") {
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return
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}
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continue
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} else {
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return
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}
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}
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b := make([]byte, n)
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copy(b, buf)
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conn.node.Write(common.CMD_CONN_UDP_MSG, conn.id, b)
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}
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}
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func (conn *serverConnect) doConnectTcp(network common.NetWork, addr string) {
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netconn, err := net.DialTimeout("tcp", addr, time.Second*30)
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if err != nil {
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buf := make([]byte, 2)
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buf[0] = byte(network)
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buf[1] = 0
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conn.node.Write(common.CMD_CONNECT_BYIDADDR_RESULT, conn.id, append(conn.randkey, buf...))
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conn.Close("fd拨号失败")
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return
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} else {
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buf := make([]byte, 2)
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buf[0] = byte(network)
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buf[1] = 1
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conn.node.Write(common.CMD_CONNECT_BYIDADDR_RESULT, conn.id, append(conn.randkey, buf...))
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if conn.close == 0 {
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conn.conn = netconn
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go conn.handTcpReceive()
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}
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}
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}
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func (conn *serverConnect) doConnectTcpWithHttpProxy(network common.NetWork, addr string) {
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writeResult := func(res bool) {
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buf := make([]byte, 2)
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buf[0] = byte(network)
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buf[1] = 0
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if res {
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buf[1] = 1
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}
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conn.node.Write(common.CMD_CONNECT_BYIDADDR_RESULT, conn.id, append(conn.randkey, buf...))
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}
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if i := strings.IndexByte(addr, 32); i > -1 {
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cfg, err := common.ParseAddr(addr[i+1:])
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if err != nil {
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writeResult(false)
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conn.Close("地址解析失败")
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return
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}
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netconn, err := net.DialTimeout("tcp", cfg.Addr(), time.Second*2)
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if err != nil {
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writeResult(false)
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conn.Close("fd拨号失败")
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return
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} else {
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netconn.SetDeadline(time.Now().Add(time.Second * 30))
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netconn.SetWriteDeadline(time.Now().Add(time.Second * 30))
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switch cfg.Scheam() {
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case "", "http://":
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//请求代理
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data := fmt.Sprintf("CONNECT %s HTTP/1.1\r\nHost: %s\r\nProxy-Connection: keep-alive\r\nUser-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.198 Safari/537.36\r\n", addr[:i], addr[:i])
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if cfg.GetHttpAuthorizationHeader() != "" {
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data += cfg.GetHttpAuthorizationHeader() + "\r\n\r\n"
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} else {
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data += "\r\n"
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}
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_, err = netconn.Write([]byte(data))
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if err != nil {
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writeResult(false)
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conn.Close("http代理发送消息失败")
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return
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}
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var resdata []byte
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var result [8192]byte
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var req = &http1request{}
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for {
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n, err := netconn.Read(result[:])
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if err != nil {
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writeResult(false)
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conn.Close("读取http代理结果失败")
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return
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}
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resdata = append(resdata, result[:n]...)
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l, _, err := parsereq(req, resdata)
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if err != nil {
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return
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} else if l > 0 {
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break
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}
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}
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if req.Status == "200 Connection established" {
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writeResult(true)
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if conn.close == 0 {
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conn.conn = netconn
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go conn.handTcpReceive()
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}
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} else {
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writeResult(false)
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conn.Close("http代理连接失败")
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}
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writeResult(true)
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case "socks5://":
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_, err = netconn.Write([]byte{5, 1, 2})
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if err != nil {
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writeResult(false)
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conn.Close("socks5代理发送消息失败")
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return
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}
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var result [8192]byte
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n, err := netconn.Read(result[:])
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if err != nil {
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writeResult(false)
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conn.Close("读取socks5数据出错")
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return
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}
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if string(result[:n]) == string([]byte{5, 2}) { //需要认证
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user, password := cfg.User(), cfg.Password()
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if user == "" && password == "" {
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writeResult(false)
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conn.Close("socks5需要验证")
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return
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}
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data := make([]byte, (3 + len(user) + len(password)))
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data[0] = 5
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data[1] = byte(len(user))
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copy(data[2:], user)
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data[2+len(user)] = byte(len(password))
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copy(data[3+len(user):], password)
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netconn.Write(data)
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n, err = netconn.Read(result[:])
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if err != nil || string(result[:n]) != string([]byte{5, 0}) {
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writeResult(false)
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conn.Close("密码校验不通过")
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return
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}
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}
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data := []byte{5, 1, 0, 1}
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if u, err := url.ParseRequestURI(addr[:i]); err == nil {
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data[3] = 3
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data = append(data, byte(len(u.Scheme)))
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data = append(data, u.Scheme...)
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p, _ := strconv.Atoi(u.Opaque)
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port := []byte{byte(p >> 8), byte(p)}
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data = append(data, port...)
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} else if tcp4, err := net.ResolveTCPAddr("tcp4", addr[:i]); err == nil {
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data[3] = 1
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data = append(data, tcp4.IP.String()...)
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port := []byte{byte(tcp4.Port), byte(tcp4.Port >> 8)}
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data = append(data, port...)
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} else if tcp6, err := net.ResolveTCPAddr("tcp6", addr[:i]); err == nil {
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data[3] = 4
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data = append(data, tcp6.IP.String()...)
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port := []byte{byte(tcp6.Port), byte(tcp6.Port >> 8)}
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data = append(data, port...)
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}
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netconn.Write(data)
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n, _ = netconn.Read(result[:])
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if n >= 2 && string(result[:2]) == string([]byte{5, 0}) {
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writeResult(true)
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if conn.close == 0 {
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conn.conn = netconn
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go conn.handTcpReceive()
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}
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} else {
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writeResult(false)
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conn.Close("socks5连接失败")
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}
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default:
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writeResult(false)
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conn.Close("不支持的代理协议")
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}
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}
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} else {
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writeResult(false)
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conn.Close("无法获取代理地址")
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}
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}
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func (conn *serverConnect) doHandleUdp() {
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for b := range conn.write {
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if b == nil {
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conn.write = closeChan
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return
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}
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conn.conn.Write(b.Bytes())
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b.Reset()
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bufPool.Put(b)
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}
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}
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var broadcastMap sync.Map //广播帧防止重复处理
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func (c *Conn) handlerNodeRead() {
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var err error
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defer func() {
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c.nodeConn.Close()
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c.Close("read错误" + err.Error())
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}()
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lengbuf := make([]byte, 2)
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for {
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_, err = io.ReadFull(c.nodeConn, lengbuf)
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if err != nil {
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if strings.Contains(err.Error(), "i/o timeout") {
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continue
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}
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return
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}
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buf := make([]byte, int(lengbuf[0])+int(lengbuf[1])<<8)
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_, err = io.ReadFull(c.nodeConn, buf)
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b := aes.AesCtrDecrypt(buf)
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msg := common.UnmarshalMsg(b)
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if common.Debug {
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fmt.Println("fromto", msg.From, msg.To, common.CmdToName[msg.CmdOpteion], int(lengbuf[0])+int(lengbuf[1])<<8)
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}
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if msg.To == common.NoneUUID.String() && c.node == nil {
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c.inChan <- func() {
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newNode := &node{
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conn: c,
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}
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newNode.do(msg)
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}
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} else if msg.To == currentNode.uuid {
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v, ok := nodeMap.Load(msg.From)
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if ok && v.(*node).port != 0 {
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c.inChan <- func() {
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v.(*node).do(msg)
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}
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} else {
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if !ok {
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newNode := &node{
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uuid: msg.From,
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conn: c,
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waitMsg: []*common.Msg{msg},
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}
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result := make(chan interface{}, 1)
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id := newNode.storeQuery(result)
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nodeMap.Store(msg.From, newNode)
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newNode.Write(common.CMD_GET_CURRENT_NODE, id, []byte{1}) //获取丢失节点的信息
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go func() {
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defer func() {
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if err := recover(); err != nil {
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fmt.Println(err)
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debug.PrintStack()
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}
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newNode.deleteQuery(id)
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}()
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select {
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case res := <-result:
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if res == nil {
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for _, m := range newNode.waitMsg {
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c.inChan <- func() {
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newNode.do(m)
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}
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}
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}
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case <-time.After(common.CMD_TIMEOUT):
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newNode.Close("超时")
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}
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}()
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} else {
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if msg.CmdOpteion == common.CMD_GET_CURRENT_NODE_RESULT {
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n := v.(*node)
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var res chan interface{}
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if _v, ok := n.loadQuery(msg.CmdId); !ok {
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return
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} else {
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res = _v
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}
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var nmsg nodeInfo
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err = json.Unmarshal(msg.CmdData, &nmsg)
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if err != nil {
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res <- err
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return
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}
|
|
n.hostName = cert.RSADecrypterStr(nmsg.HostName)
|
|
n.uuid = cert.RSADecrypterStr(nmsg.UUID)
|
|
if n.port, err = strconv.Atoi(cert.RSADecrypterStr(nmsg.Port)); err != nil {
|
|
n.port = -1
|
|
}
|
|
n.mainIp = cert.RSADecrypterStr(nmsg.MainIp)
|
|
n.goos = cert.RSADecrypterStr(nmsg.Goos)
|
|
res <- nil
|
|
} else {
|
|
v.(*node).waitMsg = append(v.(*node).waitMsg, msg)
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
} else {
|
|
|
|
key := msg.From + "_" + strconv.Itoa(int(msg.MsgId))
|
|
msg.Ttl++
|
|
if _, ok := broadcastMap.LoadOrStore(key, struct{}{}); !ok {
|
|
|
|
if msg.From != currentNode.uuid && msg.To == common.BroadcastUUID.String() && msg.Ttl < 250 { //广播
|
|
go allNodesDo(func(_n *node) (bool, error) {
|
|
if _n.uuid != currentNode.uuid {
|
|
_n.WriteMsg(msg)
|
|
}
|
|
return true, nil
|
|
})
|
|
if common.Debug {
|
|
fmt.Println("广播do")
|
|
}
|
|
|
|
newNode := &node{
|
|
conn: c,
|
|
}
|
|
c.inChan <- func() {
|
|
newNode.do(msg)
|
|
}
|
|
} else {
|
|
c.WriteToUUID(msg)
|
|
}
|
|
time.AfterFunc(time.Hour, func() {
|
|
broadcastMap.Delete(key)
|
|
})
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
func (c *Conn) handle() {
|
|
c.OutChan = make(chan []byte, 64)
|
|
c.inChan = make(chan func())
|
|
c.close = make(chan string, 999)
|
|
|
|
go func() {
|
|
for {
|
|
select {
|
|
case f := <-c.inChan:
|
|
f()
|
|
//c.do(b)
|
|
case b := <-c.OutChan:
|
|
|
|
if c.closeTag == 0 {
|
|
c.tlsWrite(b)
|
|
//var err error
|
|
for i := 0; i < len(c.OutChan); i++ {
|
|
|
|
c.tlsWrite(<-c.OutChan)
|
|
}
|
|
}
|
|
|
|
case reason := <-c.close:
|
|
c.OutChan = upNodeWrite
|
|
if c.node != nil && c.node.nextPingTime > time.Now().Unix()+5 {
|
|
c.node.ping(0)
|
|
c.node.nextPingTime = time.Now().Unix() + 5
|
|
}
|
|
connMap.Delete(c.remoteAddr)
|
|
|
|
if atomic.CompareAndSwapInt32(&c.closeTag, 0, 1) {
|
|
if common.Debug {
|
|
fmt.Println(c.nodeConn.RemoteAddr().String(), "关闭原因", reason)
|
|
}
|
|
|
|
if c.nodeConn != nil {
|
|
if common.Debug {
|
|
fmt.Println("執行close1")
|
|
}
|
|
c.nodeConn.Close()
|
|
}
|
|
|
|
if c.node != nil {
|
|
c.node.Close(reason)
|
|
//移除上游连接
|
|
for i := len(upLevelNode) - 1; i >= 0; i-- {
|
|
n := upLevelNode[i]
|
|
if n.uuid == c.node.uuid {
|
|
upLevelNode = append(upLevelNode[:i], upLevelNode[i+1:]...)
|
|
}
|
|
}
|
|
if common.Debug {
|
|
fmt.Println("upLevelNode", len(upLevelNode))
|
|
}
|
|
}
|
|
}
|
|
return
|
|
}
|
|
}
|
|
}()
|
|
|
|
}
|
|
func (c *Conn) reg() error {
|
|
|
|
var err error
|
|
reg := &RegMsg{
|
|
UUID: currentNode.uuid,
|
|
MainIp: cert.RSAEncrypterStr(currentNode.mainIp),
|
|
Port: cert.RSAEncrypterStr(strconv.Itoa(currentNode.port)),
|
|
Goos: cert.RSAEncrypterStr(currentNode.goos),
|
|
Hostname: cert.RSAEncrypterStr(currentNode.hostName),
|
|
}
|
|
regb, _ := json.Marshal(reg)
|
|
msg := common.Msg{
|
|
From: currentNode.uuid,
|
|
To: common.NoneUUID.String(),
|
|
CmdOpteion: common.CMD_REG,
|
|
CmdData: regb,
|
|
}
|
|
if err = c.tlsWrite(msg.Marshal()); err != nil {
|
|
return err
|
|
}
|
|
go c.handlerNodeRead()
|
|
return nil
|
|
}
|
|
func (c *Conn) WriteToUUID(msg *common.Msg) {
|
|
if n, ok := nodeMap.Load(msg.To); ok {
|
|
n.(*node).WriteMsg(msg)
|
|
}
|
|
}
|
|
|
|
func (c *Conn) Write(b []byte) {
|
|
|
|
c.OutChan <- b
|
|
}
|
|
|
|
func (c *Conn) tlsWrite(b []byte) error {
|
|
c.nodeConn.SetWriteDeadline(time.Now().Add(common.WRITE_DEADLINE))
|
|
n, err := c.nodeConn.Write(b)
|
|
if common.Debug {
|
|
if c.node != nil {
|
|
fmt.Println("writeto", c.node.uuid, n)
|
|
} else {
|
|
fmt.Println("writeto", common.NoneUUID, n)
|
|
}
|
|
|
|
}
|
|
if err != nil {
|
|
c.Close("Write " + err.Error())
|
|
upNodeWrite <- b
|
|
}
|
|
return err
|
|
}
|