Function checkNullConnection

lib/controller/checks.py:1414–1470

Reference: http://www.wisec.it/sectou.php?id=472f952d79293

()

@stackedmethod
def checkNullConnection():
    """
    Reference: http://www.wisec.it/sectou.php?id=472f952d79293
    """

    if conf.data:
        return False

    _ = hashDBRetrieve(HASHDB_KEYS.CHECK_NULL_CONNECTION_RESULT, True)
    if _ is not None:
        kb.nullConnection = _

        if _:
            dbgMsg = "resuming NULL connection method '%s'" % _
            logger.debug(dbgMsg)

    else:
        infoMsg = "testing NULL connection to the target URL"
        logger.info(infoMsg)

        pushValue(kb.pageCompress)
        kb.pageCompress = False

        try:
            page, headers, _ = Request.getPage(method=HTTPMETHOD.HEAD, raise404=False)

            if not page and HTTP_HEADER.CONTENT_LENGTH in (headers or {}):
                kb.nullConnection = NULLCONNECTION.HEAD

                infoMsg = "NULL connection is supported with HEAD method ('Content-Length')"
                logger.info(infoMsg)
            else:
                page, headers, _ = Request.getPage(auxHeaders={HTTP_HEADER.RANGE: "bytes=-1"})

                if page and len(page) == 1 and HTTP_HEADER.CONTENT_RANGE in (headers or {}):
                    kb.nullConnection = NULLCONNECTION.RANGE

                    infoMsg = "NULL connection is supported with GET method ('Range')"
                    logger.info(infoMsg)
                else:
                    _, headers, _ = Request.getPage(skipRead=True)

                    if HTTP_HEADER.CONTENT_LENGTH in (headers or {}):
                        kb.nullConnection = NULLCONNECTION.SKIP_READ

                        infoMsg = "NULL connection is supported with 'skip-read' method"
                        logger.info(infoMsg)

        except SqlmapConnectionException:
            pass

        finally:
            kb.pageCompress = popValue()
            kb.nullConnection = False if kb.nullConnection is None else kb.nullConnection
            hashDBWrite(HASHDB_KEYS.CHECK_NULL_CONNECTION_RESULT, kb.nullConnection, True)

    return kb.nullConnection in getPublicTypeMembers(NULLCONNECTION, True)