60 lines
1.2 KiB
Go
60 lines
1.2 KiB
Go
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package proxy
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import (
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"fmt"
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"io"
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"log"
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"net"
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)
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// RunTCPProxy starts a basic TCP reverse proxy listening on the given port
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// and forwarding all traffic to the target backend.
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func RunTCPProxy(port int, targetBackend string) error {
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addr := fmt.Sprintf(":%d", port)
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listener, err := net.Listen("tcp", addr)
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if err != nil {
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return err
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}
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defer listener.Close()
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log.Printf("Starting TCP proxy on %s, forwarding to %s\n", addr, targetBackend)
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for {
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clientConn, err := listener.Accept()
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if err != nil {
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log.Printf("TCP Accept error: %v", err)
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continue
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}
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go handleTCPConnection(clientConn, targetBackend)
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}
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}
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func handleTCPConnection(clientConn net.Conn, targetBackend string) {
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defer clientConn.Close()
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backendConn, err := net.Dial("tcp", targetBackend)
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if err != nil {
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log.Printf("TCP Dial error to %s: %v", targetBackend, err)
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return
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}
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defer backendConn.Close()
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errChan := make(chan error, 2)
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// Copy data from client to backend
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go func() {
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_, err := io.Copy(backendConn, clientConn)
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errChan <- err
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}()
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// Copy data from backend to client
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go func() {
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_, err := io.Copy(clientConn, backendConn)
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errChan <- err
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}()
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// Wait for one of the streams to finish (either EOF or error)
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<-errChan
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}
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