73 lines
1.6 KiB
Go
73 lines
1.6 KiB
Go
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package torrent
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import (
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"bytes"
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"fmt"
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"io"
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"net"
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"time"
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"github.com/anacrolix/torrent/mse"
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pp "github.com/anacrolix/torrent/peer_protocol"
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)
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// Wraps a raw connection and provides the interface we want for using the
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// connection in the message loop.
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type deadlineReader struct {
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nc net.Conn
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r io.Reader
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}
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func (r deadlineReader) Read(b []byte) (int, error) {
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// Keep-alives should be received every 2 mins. Give a bit of gracetime.
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err := r.nc.SetReadDeadline(time.Now().Add(150 * time.Second))
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if err != nil {
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return 0, fmt.Errorf("error setting read deadline: %s", err)
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}
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return r.r.Read(b)
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}
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// Handles stream encryption for inbound connections.
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func handleEncryption(
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rw io.ReadWriter,
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skeys mse.SecretKeyIter,
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policy HeaderObfuscationPolicy,
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selector mse.CryptoSelector,
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) (
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ret io.ReadWriter,
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headerEncrypted bool,
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cryptoMethod mse.CryptoMethod,
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err error,
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) {
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// Tries to start an unencrypted stream.
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if !policy.RequirePreferred || !policy.Preferred {
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var protocol [len(pp.Protocol)]byte
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_, err = io.ReadFull(rw, protocol[:])
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if err != nil {
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return
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}
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// Put the protocol back into the stream.
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rw = struct {
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io.Reader
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io.Writer
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}{
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io.MultiReader(bytes.NewReader(protocol[:]), rw),
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rw,
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}
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if string(protocol[:]) == pp.Protocol {
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ret = rw
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return
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}
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if policy.RequirePreferred {
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// We are here because we require unencrypted connections.
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err = fmt.Errorf("unexpected protocol string %q and header obfuscation disabled", protocol)
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return
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}
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}
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headerEncrypted = true
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ret, cryptoMethod, err = mse.ReceiveHandshake(rw, skeys, selector)
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return
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}
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type PeerExtensionBits = pp.PeerExtensionBits
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