137 lines
2.3 KiB
Go
137 lines
2.3 KiB
Go
package tunnel
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import (
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"sync"
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"time"
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"github.com/google/uuid"
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"github.com/micro/go-micro/transport"
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)
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type link struct {
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transport.Socket
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sync.RWMutex
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// stops the link
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closed chan bool
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// unique id of this link e.g uuid
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// which we define for ourselves
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id string
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// whether its a loopback connection
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// this flag is used by the transport listener
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// which accepts inbound quic connections
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loopback bool
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// whether its actually connected
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// dialled side sets it to connected
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// after sending the message. the
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// listener waits for the connect
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connected bool
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// the last time we received a keepalive
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// on this link from the remote side
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lastKeepAlive time.Time
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// channels keeps a mapping of channels and last seen
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channels map[string]time.Time
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// keep an error count on the link
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errCount int
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}
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func newLink(s transport.Socket) *link {
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l := &link{
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Socket: s,
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id: uuid.New().String(),
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channels: make(map[string]time.Time),
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closed: make(chan bool),
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lastKeepAlive: time.Now(),
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}
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go l.expiry()
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return l
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}
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// watches the channel expiry
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func (l *link) expiry() {
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t := time.NewTicker(time.Minute)
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defer t.Stop()
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for {
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select {
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case <-l.closed:
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return
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case <-t.C:
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// drop any channel mappings older than 2 minutes
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var kill []string
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killTime := time.Minute * 2
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l.RLock()
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for ch, t := range l.channels {
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if d := time.Since(t); d > killTime {
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kill = append(kill, ch)
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}
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}
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l.RUnlock()
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// if nothing to kill don't bother with a wasted lock
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if len(kill) == 0 {
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continue
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}
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// kill the channels!
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l.Lock()
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for _, ch := range kill {
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delete(l.channels, ch)
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}
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l.Unlock()
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}
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}
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}
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func (l *link) Id() string {
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l.RLock()
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defer l.RUnlock()
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return l.id
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}
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func (l *link) Close() error {
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select {
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case <-l.closed:
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return nil
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default:
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close(l.closed)
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return nil
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}
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return nil
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}
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func (l *link) Send(m *transport.Message) error {
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err := l.Socket.Send(m)
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l.Lock()
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defer l.Unlock()
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// if theres no error reset the counter
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if err == nil {
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l.errCount = 0
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}
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// otherwise increment the counter
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l.errCount++
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return err
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}
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func (l *link) Status() string {
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select {
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case <-l.closed:
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return "closed"
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default:
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l.RLock()
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defer l.RUnlock()
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if l.errCount > 3 {
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return "error"
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}
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return "connected"
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}
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}
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