_gnutls_recv_handshake_header (gnutls_session_t session,
			       gnutls_handshake_description_t type,
			       gnutls_handshake_description_t * recv_type)
{
  int ret;
  uint32_t length32 = 0;
  uint8_t *dataptr = NULL;	/* for realloc */
  size_t handshake_header_size = HANDSHAKE_HEADER_SIZE;

  /* if we have data into the buffer then return them, do not read the next packet.
   * In order to return we need a full TLS handshake header, or in case of a version 2
   * packet, then we return the first byte.
   */
  if (session->internals.handshake_header_buffer.header_size ==
      handshake_header_size || (session->internals.v2_hello != 0
				&& type == GNUTLS_HANDSHAKE_CLIENT_HELLO
				&& session->internals.
				handshake_header_buffer.packet_length > 0))
    {
 
       *recv_type = session->internals.handshake_header_buffer.recv_type;
 
      if (*recv_type != type)
       {
         gnutls_assert ();
         _gnutls_handshake_log
           ("HSK[%x]: Handshake type mismatch (under attack?)\n", session);
         return GNUTLS_E_UNEXPECTED_HANDSHAKE_PACKET;
       }

       return session->internals.handshake_header_buffer.packet_length;
     }
      ret =
	_gnutls_handshake_io_recv_int (session, GNUTLS_HANDSHAKE,
				       type, dataptr, SSL2_HEADERS);

      if (ret < 0)
	{
	  gnutls_assert ();
	  return ret;
	}

      /* The case ret==0 is caught here.
       */
      if (ret != SSL2_HEADERS)
	{
	  gnutls_assert ();
	  return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
	}
      session->internals.handshake_header_buffer.header_size = SSL2_HEADERS;
    }

This weakness involves numeric computation errors, such as integer overflows, underflows, or precision losses, which can lead to miscalculations and exploitable behaviors in software.