58 lines
1.4 KiB
Go
58 lines
1.4 KiB
Go
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package socks
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import (
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"bufio"
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"fmt"
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"io"
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)
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// ConnectionHandler is the Serve method to handle connections
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// from a local TCP listener of the standard library (net.Listener)
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type ConnectionHandler interface {
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Serve(io.ReadWriter) error
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}
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// StandardConnectionHandler is the base implementation of handling SOCKS5 requests
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type StandardConnectionHandler struct {
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requestHandler RequestHandler
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authHandler AuthHandler
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}
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// NewConnectionHandler creates a standard SOCKS5 connection handler
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// This process connections from a generic TCP listener from the standard library
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func NewConnectionHandler(requestHandler RequestHandler) ConnectionHandler {
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return &StandardConnectionHandler{
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requestHandler: requestHandler,
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authHandler: NewAuthHandler(),
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}
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}
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// Serve process new connection created after calling `Accept()` in the standard library
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func (h *StandardConnectionHandler) Serve(c io.ReadWriter) error {
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bufConn := bufio.NewReader(c)
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// read the version byte
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version := []byte{0}
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if _, err := bufConn.Read(version); err != nil {
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return err
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}
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// ensure compatibility
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if version[0] != socks5Version {
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return fmt.Errorf("Unsupported SOCKS version: %v", version)
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}
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// handle auth
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if err := h.authHandler.Handle(bufConn, c); err != nil {
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return err
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}
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// process command/request
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req, err := NewRequest(bufConn)
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if err != nil {
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return err
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}
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return h.requestHandler.Handle(req, c)
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}
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