conduit/tunnel/http.go
Evan Reichard 2e73689762
All checks were successful
continuous-integration/drone/push Build is passing
http vs tcp tunnel
2025-09-22 23:04:15 -04:00

105 lines
2.1 KiB
Go

package tunnel
import (
"fmt"
"io"
"net"
"net/http"
"net/http/httputil"
"net/url"
"sync"
)
func HTTPConnectionBuilder(targetURL *url.URL) (ConnBuilder, error) {
multiConnListener := newMultiConnListener()
// Create Reverse Proxy
proxy := &httputil.ReverseProxy{
Director: func(req *http.Request) {
req.Host = targetURL.Host
req.URL.Host = targetURL.Host
req.URL.Scheme = targetURL.Scheme
},
ErrorHandler: func(w http.ResponseWriter, r *http.Request, err error) {
http.Error(w, fmt.Sprintf("Proxy error: %v", err), http.StatusBadGateway)
},
}
// Start HTTP Proxy
go func() {
defer multiConnListener.Close()
_ = http.Serve(multiConnListener, proxy)
}()
// Return Connection Builder
return func() (conn io.ReadWriteCloser, err error) {
clientConn, serverConn := net.Pipe()
if err := multiConnListener.addConn(serverConn); err != nil {
_ = clientConn.Close()
_ = serverConn.Close()
return nil, err
}
return clientConn, nil
}, nil
}
type multiConnListener struct {
connCh chan net.Conn
closed chan struct{}
once sync.Once
}
func newMultiConnListener() *multiConnListener {
return &multiConnListener{
connCh: make(chan net.Conn, 100),
closed: make(chan struct{}),
}
}
func (l *multiConnListener) Accept() (net.Conn, error) {
select {
case conn := <-l.connCh:
if conn == nil {
return nil, fmt.Errorf("listener closed")
}
return conn, nil
case <-l.closed:
return nil, fmt.Errorf("listener closed")
}
}
func (l *multiConnListener) Close() error {
l.once.Do(func() {
close(l.closed)
// Drain any remaining connections
go func() {
for conn := range l.connCh {
if conn != nil {
conn.Close()
}
}
}()
close(l.connCh)
})
return nil
}
func (l *multiConnListener) Addr() net.Addr {
return &net.TCPAddr{IP: net.IPv4(127, 0, 0, 1), Port: 0}
}
func (l *multiConnListener) addConn(conn net.Conn) error {
select {
case l.connCh <- conn:
return nil
case <-l.closed:
conn.Close()
return fmt.Errorf("listener is closed")
default:
conn.Close()
return fmt.Errorf("connection queue full")
}
}