Method handlePostHandshakeMessage

conn.go:1464–1489

handlePostHandshakeMessage processes a handshake message arrived after the handshake is complete. Up to TLS 1.2, it indicates the start of a renegotiation.

()

// handlePostHandshakeMessage processes a handshake message arrived after the
// handshake is complete. Up to TLS 1.2, it indicates the start of a renegotiation.
func (c *Conn) handlePostHandshakeMessage() error {
	if c.vers != VersionTLS13 {
		return c.handleRenegotiation()
	}

	msg, err := c.readHandshake()
	if err != nil {
		return err
	}

	c.retryCount++
	if c.retryCount > maxUselessRecords {
		c.sendAlert(alertUnexpectedMessage)
		return c.in.setErrorLocked(errors.New("tls: too many non-advancing records"))
	}

	switch msg := msg.(type) {
	case *newSessionTicketMsgTLS13:
		return c.handleNewSessionTicket(msg)
	case *keyUpdateMsg:
		return c.handleKeyUpdate(msg)
	default:
		c.sendAlert(alertUnexpectedMessage)
		return fmt.Errorf("tls: received unexpected handshake message of type %T", msg)
	}
}

func (c *Conn) handleKeyUpdate(keyUpdate *keyUpdateMsg) error {
	cipherSuite := cipherSuiteTLS13ByID(c.cipherSuite)