if err != nil {
			return nil, err
		}
	}
	return fullMessage[:len(fullMessage)-bindersLen], nil
}

// updateBinders updates the m.pskBinders field. The supplied binders must have
// the same length as the current m.pskBinders.
func (m *clientHelloMsg) updateBinders(pskBinders [][]byte) error {
	if len(pskBinders) != len(m.pskBinders) {
		return errors.New("tls: internal error: pskBinders length mismatch")
	}

	helloBytes, err := m.marshalWithoutBinders()
	if err != nil {
		return err
	}
	transcript.Write(helloBytes)
	pskBinders := [][]byte{finishedHash(binderKey, transcript)}
	return m.updateBinders(pskBinders)