66 lines
1.3 KiB
Go
66 lines
1.3 KiB
Go
package transport
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import (
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"errors"
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"fmt"
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"io"
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"log"
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"net"
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"golang.org/x/crypto/ssh"
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)
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type tcp struct {
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port uint16
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forwarder Forwarder
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}
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type Forwarder interface {
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CreateForwardedTCPIPPayload(origin net.Addr) []byte
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OpenForwardedChannel(payload []byte) (ssh.Channel, <-chan *ssh.Request, error)
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HandleConnection(dst io.ReadWriter, src ssh.Channel)
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}
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func NewTCPServer(port uint16, forwarder Forwarder) Transport {
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return &tcp{
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port: port,
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forwarder: forwarder,
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}
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}
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func (tt *tcp) Listen() (net.Listener, error) {
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return net.Listen("tcp", fmt.Sprintf("0.0.0.0:%d", tt.port))
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}
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func (tt *tcp) Serve(listener net.Listener) error {
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for {
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conn, err := listener.Accept()
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if err != nil {
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if errors.Is(err, net.ErrClosed) {
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return nil
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}
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log.Printf("Error accepting connection: %v", err)
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continue
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}
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go tt.handleTcp(conn)
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}
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}
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func (tt *tcp) handleTcp(conn net.Conn) {
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defer func() {
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err := conn.Close()
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if err != nil {
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log.Printf("Failed to close connection: %v", err)
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}
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}()
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payload := tt.forwarder.CreateForwardedTCPIPPayload(conn.RemoteAddr())
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channel, reqs, err := tt.forwarder.OpenForwardedChannel(payload)
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if err != nil {
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log.Printf("Failed to open forwarded-tcpip channel: %v", err)
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return
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}
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go ssh.DiscardRequests(reqs)
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tt.forwarder.HandleConnection(conn, channel)
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}
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