package telebit import ( "net" "time" ) // ConnWrap is just a cheap way to DRY up some switch conn.(type) statements to handle special features of Conn type ConnWrap struct { Conn net.Conn Plain net.Conn } func (c *ConnWrap) Read(b []byte) (n int, err error) { return c.Conn.Read(b) } // Write writes data to the connection. // Write can be made to time out and return an Error with Timeout() == true // after a fixed time limit; see SetDeadline and SetWriteDeadline. func (c *ConnWrap) Write(b []byte) (n int, err error) { return c.Conn.Write(b) } // Close closes the connection. // Any blocked Read or Write operations will be unblocked and return errors. func (c *ConnWrap) Close() error { return c.Conn.Close() } // Scheme returns one of "https", "http", "tcp", "tls", or "" func (c *ConnWrap) Scheme() string { if nil != c.Plain { tlsConn := &ConnWrap{Conn: c.Plain} return tlsConn.Scheme() } switch conn := c.Conn.(type) { case *ConnWrap: return conn.Scheme() case *Conn: return string(conn.relayTargetAddr.scheme) } return "" } // Servername may return Servername or Hostname as hinted by a tunnel or buffered peeking func (c *ConnWrap) Servername() string { if nil != c.Plain { tlsConn := &ConnWrap{Conn: c.Plain} return tlsConn.Scheme() } switch conn := c.Conn.(type) { case *ConnWrap: return conn.Scheme() case *Conn: return string(conn.relaySourceAddr.scheme) } return "" } // isTerminated returns true if net.Conn is either a ConnWrap{ tls.Conn }, // or a telebit.Conn with a non-encrypted `scheme` such as "tcp" or "http". func (c *ConnWrap) isTerminated() bool { if nil != c.Plain { return true } switch conn := c.Conn.(type) { case *ConnWrap: return conn.isTerminated() case *Conn: _, ok := encryptedSchemes[string(conn.relayTargetAddr.scheme)] return !ok } return false } // LocalAddr returns the local network address. func (c *ConnWrap) LocalAddr() net.Addr { // TODO is this the right one? return c.Conn.LocalAddr() } // RemoteAddr returns the remote network address. func (c *ConnWrap) RemoteAddr() net.Addr { // TODO is this the right one? return c.Conn.RemoteAddr() } // SetDeadline sets the read and write deadlines associated // with the connection. It is equivalent to calling both // SetReadDeadline and SetWriteDeadline. // // A deadline is an absolute time after which I/O operations // fail with a timeout (see type Error) instead of // blocking. The deadline applies to all future and pending // I/O, not just the immediately following call to Read or // Write. After a deadline has been exceeded, the connection // can be refreshed by setting a deadline in the future. // // An idle timeout can be implemented by repeatedly extending // the deadline after successful Read or Write calls. // // A zero value for t means I/O operations will not time out. // // Note that if a TCP connection has keep-alive turned on, // which is the default unless overridden by Dialer.KeepAlive // or ListenConfig.KeepAlive, then a keep-alive failure may // also return a timeout error. On Unix systems a keep-alive // failure on I/O can be detected using // errors.Is(err, syscall.ETIMEDOUT). func (c *ConnWrap) SetDeadline(t time.Time) error { return c.Conn.SetDeadline(t) } // SetReadDeadline sets the deadline for future Read calls // and any currently-blocked Read call. // A zero value for t means Read will not time out. func (c *ConnWrap) SetReadDeadline(t time.Time) error { return c.Conn.SetReadDeadline(t) } // SetWriteDeadline sets the deadline for future Write calls // and any currently-blocked Write call. // Even if write times out, it may return n > 0, indicating that // some of the data was successfully written. // A zero value for t means Write will not time out. func (c *ConnWrap) SetWriteDeadline(t time.Time) error { return c.Conn.SetWriteDeadline(t) }