71 lines
2.1 KiB
Go
71 lines
2.1 KiB
Go
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package datagramsession
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import (
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"context"
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"io"
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"github.com/google/uuid"
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)
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// Each Session is a bidirectional pipe of datagrams between transport and dstConn
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// Currently the only implementation of transport is quic DatagramMuxer
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// Destination can be a connection with origin or with eyeball
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// When the destination is origin:
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// - Datagrams from edge are read by Manager from the transport. Manager finds the corresponding Session and calls the
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// write method of the Session to send to origin
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// - Datagrams from origin are read from conn and SentTo transport. Transport will return them to eyeball
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// When the destination is eyeball:
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// - Datagrams from eyeball are read from conn and SentTo transport. Transport will send them to cloudflared
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// - Datagrams from cloudflared are read by Manager from the transport. Manager finds the corresponding Session and calls the
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// write method of the Session to send to eyeball
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type Session struct {
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id uuid.UUID
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transport transport
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dstConn io.ReadWriteCloser
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doneChan chan struct{}
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}
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func newSession(id uuid.UUID, transport transport, dstConn io.ReadWriteCloser) *Session {
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return &Session{
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id: id,
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transport: transport,
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dstConn: dstConn,
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doneChan: make(chan struct{}),
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}
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}
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func (s *Session) Serve(ctx context.Context) error {
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serveCtx, cancel := context.WithCancel(ctx)
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defer cancel()
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go func() {
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select {
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case <-serveCtx.Done():
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case <-s.doneChan:
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}
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s.dstConn.Close()
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}()
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// QUIC implementation copies data to another buffer before returning https://github.com/lucas-clemente/quic-go/blob/v0.24.0/session.go#L1967-L1975
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// This makes it safe to share readBuffer between iterations
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readBuffer := make([]byte, 1280)
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for {
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// TODO: TUN-5303: origin proxy should determine the buffer size
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n, err := s.dstConn.Read(readBuffer)
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if n > 0 {
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if err := s.transport.SendTo(s.id, readBuffer[:n]); err != nil {
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return err
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}
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}
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if err != nil {
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return err
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}
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}
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}
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func (s *Session) writeToDst(payload []byte) (int, error) {
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return s.dstConn.Write(payload)
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}
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func (s *Session) close() {
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close(s.doneChan)
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}
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