code: func (h *HandshakeContext) handshakeRetransmit() error {
  	if _, err := h.hOut.SendQueuedMessages(); err != nil {
  		return err
  	}
  
  	h.timers.start(retransmitTimerLabel,
  		h.handshakeRetransmit,
  		h.timeoutMS)
  
  	// TODO(ekr@rtfm.com): Back off timer
  	return nil
  }
docs: // TODO(ekr@rtfm.com): Move these to state-machine.go