--- -- DRDA Library supporting a very limited subset of operations. -- -- Summary -- * The library currently provides functionality to: (1) Query the server for -- basic settings using the getServerInfo function of the helper -- class. (2) Authenticate to a DB2 server using a plain-text username and -- password. -- -- The library contains the following classes: -- * DRDA -- ** Implements the Distributed Relational Database Architecture class . -- * DRDAParameter -- ** Implements a number of functions to handle DRDA parameters. -- * DDM -- ** Implements the DDM portion of the DRDA structure -- * Command -- ** Provides functions for easy creation of the most common DRDAs. -- ** Implemented as a static class that returns an instance of the DRDA. -- * Helper -- ** A helper class that provides easy access to the rest of the library -- * DB2Socket -- ** A smallish socket wrapper that provides fundamental buffering -- * StringUtil -- ** Provides EBCDIC/ASCII conversion functions -- * Comm -- ** Provides fundamental communication support (send/receive DRDAPacket) -- * DRDAPacket -- ** A class holding one or more DRDA's and provides some basic access methods -- -- The following sample code illustrates how scripts can use the Helper class -- to interface with the library: -- -- -- db2helper = drda.Helper:new() -- status, err = db2helper:connect(host, port) -- status, res = db2helper:getServerInfo() -- status, err = db2helper:close() -- -- -- The implementation is based on packet dumps and the excellent decoding -- provided by Wireshark. -- -- There is some documentation at -- http://publib.boulder.ibm.com/infocenter/dzichelp/v2r2/topic/com.ibm.db29.doc.drda/db2z_drda.htm. -- -- @copyright Same as Nmap--See https://nmap.org/book/man-legal.html -- @author Patrik Karlsson -- -- -- Version 0.2 -- Created 05/08/2010 - v0.1 - created by Patrik Karlsson -- Revised 07/27/2010 - v0.2 - Added the comm class and made a few improvements -- to sending and receiving packets. Changed the -- helper login method to support: -- x IBM DB2 -- x Apache Derby -- x IBM Informix Dynamic Server local match = require "match" local nmap = require "nmap" local stdnse = require "stdnse" local string = require "string" local table = require "table" _ENV = stdnse.module("drda", stdnse.seeall) -- CodePoint constants CodePoint = { CODEPNT = 0x000c, TYPDEFNAM = 0x002f, TYPDEFOVR = 0x0035, ACCSEC = 0x106d, SECCHK = 0x106e, EXCSAT = 0x1041, PRDID = 0x112e, SRVCLSNM = 0x1147, SVRCOD = 0x1149, SYNERRCD = 0x114a, SRVRLSLV = 0x115a, EXTNAM = 0x115e, SRVNAM = 0x116d, USRID = 0x11a0, PASSWORD = 0x11a1, SECMEC = 0x11a2, SECCHKCD = 0x11a4, SECCHKRM = 0x1219, SYNTAXRM = 0x124c, MGRLVLLS = 0x1404, EXCSATRD = 0x1443, ACCSECRD = 0x14ac, ACCRDB = 0x2001, PRDDATA = 0x2104, RDBACCL = 0x210f, RDBNAM = 0x2110, CRRTKN = 0x2135, ACCRDBRM = 0x2201, RDBNFNRM = 0x2211, RDBAFLRM = 0x221a, RDBATHRM = 0x22cb, } -- Security Mechanism SecMec = { USER_PASSWORD = 0x0003, USER_ONLY = 0x0004, CHANGE_PASSWORD = 0x0005, USER_PASS_SUBST = 0x0006, USER_ENC_PASS = 0x0007, ENC_USER_ENC_PASS = 0x0009, ENC_CHANGE_PASS = 0x000A, KERBEROS = 0x000B, ENC_USER_DATA = 0x000C, ENC_USER_ENC_PASS_ENC_DATA = 0x000D, ENC_USER_ENC_PASS_ENC_NEWPASS_ENC_DATA = 0x000E, } DRDAPacket = { new = function(self, drda_array) local o = { drda_array = drda_array, count = #drda_array } setmetatable(o, self) self.__index = self return o end, getDRDAByCodePoint = function( self, codepoint ) for i=1, #self.drda_array do if ( self.drda_array[i].DDM.CodePoint == codepoint ) then return self.drda_array[i] end end end, getDRDA = function( self, n ) return ( #self.drda_array >= n ) and self.drda_array[n] or nil end, __tostring = function( self ) local data = "" -- do some DDM fixup in here for i=1, #self.drda_array do if ( i == 1 and #self.drda_array > 1 ) then self.drda_array[1].DDM.Format = 0x41 else self.drda_array[i].DDM.Format = 0x01 end self.drda_array[i].DDM.CorelId = i data = data .. tostring(self.drda_array[i]) end return data end } -- Distributed Relational Database Architecture (DRDA) Class DRDA = { new = function(self, ddm) local o = { Parameters = {}, DDM = ddm } setmetatable(o, self) self.__index = self return o end, --- Sets the DDM -- -- @param ddm DDM to assign to the DRDA -- @return status boolean true on success, false on failure setDDM = function( self, ddm ) if ( not(ddm) ) then return false, "DDM cannot be nil" end self.DDM = ddm return true end, --- Adds a DRDA parameter to the table -- -- @param param DRDAParam containing the parameter to add to the table -- @return status bool true on success, false on failure -- @return err string containing the error message if status is false addParameter = function( self, param ) if ( not(self.DDM) ) then stdnse.debug1("drda.DRDA.addParameter: DDM must be set prior to adding parameters") return false, "DDM must be set prior to adding parameters" end if ( not(param) ) then stdnse.debug1("drda.DRDA.addParameter: Param cannot be nil") return false, "Param cannot be nil" end table.insert(self.Parameters, param) -- update the DDM length fields self.DDM.Length = self.DDM.Length + param.Length self.DDM.Length2 = self.DDM.Length2 + param.Length return true end, --- Gets a parameter from the DRDA parameter table -- -- @param codepoint number containing the parameter type ro retrieve -- @return param DRDAParameter containing the requested parameter getParameter = function( self, codepoint ) for _, v in ipairs( self.Parameters ) do if ( v.CodePoint == codepoint ) then return v end end return end, --- Converts the DRDA class to a string -- -- @return data containing the object instance __tostring = function(self) if ( not(self.DDM) ) then stdnse.debug1("drda.DRDA.toString: DDM cannot be nil") return nil end local data = { string.pack(">I2BBI2I2I2", self.DDM.Length, self.DDM.Magic, self.DDM.Format, self.DDM.CorelId, self.DDM.Length2, self.DDM.CodePoint ) } for k,v in ipairs(self.Parameters) do data[#data+1] = tostring(v) end return table.concat(data) end, --- Sends the DRDA over the db2socket -- -- @param db2socket DB2Socket over which to send the data -- @return Status (true or false). -- @return Error code (if status is false). send = function( self, db2socket ) return db2socket:send( tostring(self) ) end, --- Receives data from the db2socket and builds a DRDA object -- -- @param db2socket from which to read data -- @return Status (true or false). -- @return Data (if status is true) or error string (if status is false). receive = function( self, db2socket ) local DDM_SIZE = 10 local pos = 1 -- first read atleast enough so that we can populate the DDM local status, data = db2socket:receive_buf( match.numbytes(DDM_SIZE), true ) if ( not(status) ) then stdnse.debug1("drda.DRDA.receive: %s", data) return false, ("Failed to read at least %d bytes from socket"):format(DDM_SIZE) end local ddm = DDM:new() ddm:fromString( data ) self:setDDM( ddm ) status, data = db2socket:receive_buf( match.numbytes(ddm.Length - 10), true ) if ( not(status) ) then return false, ("Failed to read the remaining %d bytes of the DRDA message") end -- add parameters until pos reaches the "end" repeat local param = DRDAParameter:new() pos = param:fromString( data, pos ) self:addParameter( param ) until ( #data <= pos ) return true end, } -- The DRDAParameter class implements the DRDA parameters DRDAParameter = { --- DRDA Parameter constructor -- -- @param codepoint number containing the codepoint value -- @param data string containing the data portion of the DRDA parameter -- @return o DRDAParameter object new = function(self, codepoint, data) local o = { CodePoint = codepoint, Data = data, Length = ( data and #data + 4 or 4 ) } setmetatable(o, self) self.__index = self return o end, --- Converts the DRDA Parameter object to a string -- -- @return data string containing the DRDA Parameter __tostring = function( self ) return string.pack(">I2I2", self.Length, self.CodePoint) .. (self.Data or "") end, --- Builds a DRDA Parameter from a string -- -- @param data string from which to build the DRDA Parameter -- @param pos number containing the offset into data -- @return pos the new position after processing, -1 on error fromString = function( self, data, pos ) if( #data < 4 ) then return -1 end self.Length, self.CodePoint, pos = string.unpack( ">I2I2", data, pos ) if ( self.Length > 0 ) then self.Data, pos = string.unpack("c" .. self.Length - 4, data, pos ) end return pos end, --- Returns the data portion of the parameter as an ASCII string -- -- @return str containing the data portion of the DRDA parameter as ASCII getDataAsASCII = function( self ) return StringUtil.toASCII( self.Data ) end, --- Returns the data in EBCDIC format -- -- @return str containing the data portion of the DRDA parameter in EBCDIC getData = function( self ) return self.Data end, } -- Distributed data management (DDM) DDM = { Formats = { RESERVED = 0x80, CHAINED = 0x40, CONTINUE = 0x20, SAME_CORRELATION = 0x10, }, Length = 10, Magic = 0xD0, Format = 0x41, CorelId = 1, Length2 = 4, CodePoint = 0, --- Creates a new DDM packet -- -- @param codepoint -- @param format -- @param corelid -- @return DDM object new = function(self, codepoint, format, corelid) local o = { CodePoint = codepoint, Format = format, CorelId = corelid } setmetatable(o, self) self.__index = self return o end, --- Converts the DDM object to a string __tostring = function( self ) return string.pack(">I2BBI2I2I2", self.Length, self.Magic, self.Format, self.CorelId, self.Length2, self.CodePoint) end, --- Constructs a DDM object from a string -- -- @param str containing the data from which to construct the object fromString = function( self, str ) local DDM_SIZE = 10 local pos = 1 if ( #str < DDM_SIZE ) then return -1, ("drda.DDM.fromString: str was less than DDM_SIZE (%d)"):format( DDM_SIZE ) end self.Length, self.Magic, self.Format, self.CorelId, self.Length2, self.CodePoint, pos = string.unpack( ">I2BBI2I2I2", str ) return pos end, --- Verifiers if there are additional DRDA's following -- -- @return true if the DRDA is to be chained, false if it's the last one isChained = function( self ) if ( (self.Format & DDM.Formats.CHAINED) == DDM.Formats.CHAINED ) then return true end return false end, --- Set the DRDA as chained (more following) -- -- @param chained boolean true if more DRDA's are following setChained = function( self, chained ) if ( self:isChained() ) then self.Format = ( self.Format ~ self.Formats.CHAINED ) else self.Format = ( self.Format | self.Formats.CHAINED ) end end, } -- static DRDA packet construction class Command = { --- Builds an EXCSAT DRDA packet -- -- @param extname string containing the external name -- @param srvname string containing the server name -- @param rellev string containing the server product release level -- @param mgrlvlls string containing the manager level list -- @param srvclass string containing the server class name -- @return drda DRDA instance EXCSAT = function( extname, srvname, rellev, mgrlvlls, srvclass ) local drda = DRDA:new( DDM:new( CodePoint.EXCSAT ) ) drda:addParameter( DRDAParameter:new( CodePoint.EXTNAM, StringUtil.toEBCDIC( extname ) ) ) drda:addParameter( DRDAParameter:new( CodePoint.SRVNAM, StringUtil.toEBCDIC( srvname ) ) ) drda:addParameter( DRDAParameter:new( CodePoint.SRVRLSLV, StringUtil.toEBCDIC( rellev ) ) ) drda:addParameter( DRDAParameter:new( CodePoint.MGRLVLLS, mgrlvlls ) ) drda:addParameter( DRDAParameter:new( CodePoint.SRVCLSNM, StringUtil.toEBCDIC( srvclass ) ) ) return drda end, --- Builds an ACCSEC DRDA packet -- -- @param secmec number containing the security mechanism ID -- @param database string containing the database name -- @return drda DRDA instance ACCSEC = function( secmec, database ) local drda = DRDA:new( DDM:new( CodePoint.ACCSEC ) ) drda:addParameter( DRDAParameter:new( CodePoint.SECMEC, secmec )) drda:addParameter( DRDAParameter:new( CodePoint.RDBNAM, StringUtil.toEBCDIC(StringUtil.padWithChar(database,' ', 18)) )) return drda end, --- Builds a SECCHK DRDA packet -- -- @param secmec number containing the security mechanism ID -- @param database string containing the database name -- @param username string -- @param password string -- @return drda DRDA instance SECCHK = function( secmec, database, username, password ) local drda = DRDA:new( DDM:new( CodePoint.SECCHK ) ) drda:addParameter( DRDAParameter:new( CodePoint.SECMEC, secmec )) drda:addParameter( DRDAParameter:new( CodePoint.RDBNAM, StringUtil.toEBCDIC(StringUtil.padWithChar(database,' ', 18)) )) drda:addParameter( DRDAParameter:new( CodePoint.USRID, StringUtil.toEBCDIC(username) ) ) drda:addParameter( DRDAParameter:new( CodePoint.PASSWORD, StringUtil.toEBCDIC(password) ) ) return drda end, --- Builds an ACCRDB DRDA packet -- -- @param database string containing the database name -- @param rdbaccl string containing the RDB access manager class -- @param prdid string containing the product id -- @param typdefnam string containing the data type definition name -- @param typdefovr string containing the data type definition override -- @return drda DRDA instance ACCRDB = function( database, rdbaccl, prdid, prddata, typdefnam, crrtkn, typdefovr ) local drda = DRDA:new( DDM:new( CodePoint.ACCRDB ) ) drda:addParameter( DRDAParameter:new( CodePoint.RDBNAM, StringUtil.toEBCDIC(StringUtil.padWithChar(database,' ', 18)) ) ) if ( rdbaccl ) then drda:addParameter( DRDAParameter:new( CodePoint.RDBACCL, rdbaccl ) ) end if ( prdid ) then drda:addParameter( DRDAParameter:new( CodePoint.PRDID, StringUtil.toEBCDIC( prdid ) ) ) end if ( prddata ) then drda:addParameter( DRDAParameter:new( CodePoint.PRDDATA, StringUtil.toEBCDIC( prddata ) ) ) end if( typdefnam ) then drda:addParameter( DRDAParameter:new( CodePoint.TYPDEFNAM, StringUtil.toEBCDIC( typdefnam ) ) ) end if( crrtkn ) then drda:addParameter( DRDAParameter:new( CodePoint.CRRTKN, crrtkn ) ) end if( typdefovr ) then drda:addParameter( DRDAParameter:new( CodePoint.TYPDEFOVR, typdefovr ) ) end return drda end } -- Helper Class Helper = { new = function(self) local o = {} setmetatable(o, self) self.__index = self return o end, --- Connect to the DB2 host -- -- @param host table -- @param port table -- @return Status (true or false). -- @return Error code (if status is false). connect = function( self, host, port ) self.comm = Comm:new( host, port ) return self.comm:connect() end, --- Closes an open connection. -- -- @return Status (true or false). -- @return Error code (if status is false). close = function( self ) self.comm:close() end, --- Returns Server Information (name, platform, version) -- -- @return table containing extname, srvclass, -- srvname and prodrel getServerInfo = function( self ) local mgrlvlls = stdnse.fromhex("1403000724070008240f00081440000814740008") local drda_excsat = Command.EXCSAT( "", "", "", mgrlvlls, "" ) local response, param, err local status, packet = self.comm:exchDRDAPacket( DRDAPacket:new( { drda_excsat } ) ) if ( not(status) ) then return false, err end local drda = packet:getDRDAByCodePoint( CodePoint.EXCSATRD ) if ( drda ) then response = {} param = drda:getParameter( CodePoint.EXTNAM ) if ( param ) then response.extname = param:getDataAsASCII() end param = drda:getParameter( CodePoint.SRVCLSNM ) if ( param ) then response.srvclass = param:getDataAsASCII() end param = drda:getParameter( CodePoint.SRVNAM ) if ( param ) then response.srvname = param:getDataAsASCII() end param = drda:getParameter( CodePoint.SRVRLSLV ) if ( param ) then response.prodrel = param:getDataAsASCII() end else return false, "The response contained no EXCSATRD" end return true, response end, --- Login to DB2 database server -- -- @param database containing the name of the database -- @param username containing the authentication username -- @param password containing the authentication password -- @return Status (true or false) -- @return err message (if status if false) login = function( self, database, username, password ) local mgrlvlls = stdnse.fromhex("1403000724070008240f00081440000814740008") local secmec, prdid = "\00\03", "JCC03010" local tdovr = stdnse.fromhex("0006119c04b80006119d04b00006119e04b8") local crrtkn= stdnse.fromhex("d5c6f0f0f0f0f0f14bc3c6f4c4012a11168414") local drda_excsat = Command.EXCSAT( "", "", "", mgrlvlls, "" ) local drda_accsec = Command.ACCSEC( secmec, database ) local drda_secchk = Command.SECCHK( secmec, database, username, password ) local drda_accrdb = Command.ACCRDB( database, "\x24\x07", "DNC10060", nil, "QTDSQLASC", crrtkn, tdovr) local status, packet = self.comm:exchDRDAPacket( DRDAPacket:new( { drda_excsat, drda_accsec } ) ) if( not(status) ) then return false, packet end if ( packet:getDRDAByCodePoint( CodePoint.RDBNFNRM ) or packet:getDRDAByCodePoint( CodePoint.RDBAFLRM ) ) then stdnse.debug1("drda.Helper.login: ERROR: RDB not found") return false, "ERROR: Database not found" end local drda = packet:getDRDAByCodePoint( CodePoint.ACCSECRD ) if ( not(drda) ) then return false, "ERROR: Response did not contain any valid security mechanisms" end local param = drda:getParameter( CodePoint.SECMEC ) if ( not(param) ) then stdnse.debug1("drda.Helper.login: ERROR: Response did not contain any valid security mechanisms") return false, "ERROR: Response did not contain any valid security mechanisms" end if ( string.unpack(">I2", param:getData()) ~= SecMec.USER_PASSWORD ) then stdnse.debug1("drda.Helper.login: ERROR: Securite Mechanism not supported") return false, "ERROR: Security mechanism not supported" end status, packet = self.comm:exchDRDAPacket( DRDAPacket:new( { drda_secchk, drda_accrdb } ) ) if( not(status) ) then return false, "ERROR: Login failed" end -- -- At this point we have a few differences in behaviour -- * DB2 has told us earlier if the DB does not exist -- * Apache Derby will do so here, regardless of the login was -- successful or not -- * Informix will tell us that the DB does not exist IF the -- login was successful -- -- Therefore the order of these checks are important!! if ( packet:getDRDAByCodePoint( CodePoint.ACCRDBRM ) ) then return true -- Apache Derby responds differently with usernames containing spaces elseif ( packet:getDRDAByCodePoint( CodePoint.RDBATHRM ) ) then return false, "ERROR: Login failed" -- Informix responds with a SECCHKRM DDM response elseif ( packet:getDRDAByCodePoint( CodePoint.SECCHKRM ) ) then drda = packet:getDRDAByCodePoint( CodePoint.SECCHKRM ) param= drda:getParameter( CodePoint.SECCHKCD ) if ( param and param:getData() == "\0" ) then return true end elseif ( packet:getDRDAByCodePoint( CodePoint.RDBNFNRM ) or packet:getDRDAByCodePoint( CodePoint.RDBAFLRM ) ) then return false, "ERROR: Database not found" end return false, "ERROR: Login failed" end, } -- The communication class Comm = { new = function(self, host, port) local o = { host = host, port = port, socket = nmap.new_socket() } setmetatable(o, self) self.__index = self return o end, connect = function(self) return self.socket:connect(self.host, self.port) end, close = function(self) return self.socket:close() end, recvDRDA = function( self ) local drda_tbl = {} repeat local drda = DRDA:new() local status, err = drda:receive( self.socket ) if ( not(status) ) then return false, err end table.insert(drda_tbl, drda) until ( not(drda.DDM:isChained()) ) return true, drda_tbl end, --- Sends a packet to the server and receives the response -- -- @param DRDAPacket -- @return status true on success, false on failure -- @return packet an instance of DRDAPacket exchDRDAPacket = function( self, packet ) local drda, err local status, err = self.socket:send( tostring(packet) ) if ( not(status) ) then stdnse.debug1("drda.Helper.login: ERROR: DB2Socket error: %s", err ) return false, ("ERROR: DB2Socket error: %s"):format( err ) end status, drda = self:recvDRDA() if( not(status) ) then stdnse.debug1("drda.Helper.login: ERROR: DB2Socket error: %s", drda ) return false, ("ERROR: DB2Socket error: %s"):format( drda ) end return true, DRDAPacket:new( drda ) end } -- EBCDIC/ASCII Conversion tables a2e_hex = "00010203372D2E2F1605250B0C0D0E0F101112133C3D322618193F271C1D1E1F\z 405A7F7B5B6C507D4D5D5C4E6B604B61F0F1F2F3F4F5F6F7F8F97A5E4C7E6E6F\z 7CC1C2C3C4C5C6C7C8C9D1D2D3D4D5D6D7D8D9E2E3E4E5E6E7E8E9ADE0BD5F6D\z 79818283848586878889919293949596979899A2A3A4A5A6A7A8A9C04FD0A107\z 202122232415061728292A2B2C090A1B30311A333435360838393A3B04143EE1\z 4142434445464748495152535455565758596263646566676869707172737475\z 767778808A8B8C8D8E8F909A9B9C9D9E9FA0AAABAC4AAEAFB0B1B2B3B4B5B6B7\z B8B9BABBBC6ABEBFCACBCCCDCECFDADBDCDDDEDFEAEBECEDEEEFFAFBFCFDFEFF" e2a_hex = "000102039C09867F978D8E0B0C0D0E0F101112139D8508871819928F1C1D1E1F\z 80818283840A171B88898A8B8C050607909116939495960498999A9B14159E1A\z 20A0A1A2A3A4A5A6A7A8D52E3C282B7C26A9AAABACADAEAFB0B121242A293B5E\z 2D2FB2B3B4B5B6B7B8B9E52C255F3E3FBABBBCBDBEBFC0C1C2603A2340273D22\z C3616263646566676869C4C5C6C7C8C9CA6A6B6C6D6E6F707172CBCCCDCECFD0\z D17E737475767778797AD2D3D45BD6D7D8D9DADBDCDDDEDFE0E1E2E3E45DE6E7\z 7B414243444546474849E8E9EAEBECED7D4A4B4C4D4E4F505152EEEFF0F1F2F3\z 5C9F535455565758595AF4F5F6F7F8F930313233343536373839FAFBFCFDFEFF" -- Creates the lookup tables needed for conversion a2e_tbl = stdnse.fromhex(a2e_hex) e2a_tbl = stdnse.fromhex(e2a_hex) -- Handle EBCDIC/ASCII conversion StringUtil = { --- Converts an ASCII string to EBCDIC -- -- @param ascii string containing the ASCII value -- @return string containing the EBCDIC value toEBCDIC = function( ascii ) return string.gsub(ascii, ".", function(a) local val = a:byte() + 1 return a2e_tbl:sub(val, val) end) end, --- Converts an EBCDIC string to ASCII -- -- @param ebcdic string containing EBCDIC value -- @return string containing ASCII value toASCII = function( ebcdic ) return string.gsub(ebcdic, ".", function(e) local val = e:byte() + 1 return e2a_tbl:sub(val, val) end) end, --- Pads a string with a character -- -- @param str string to pad -- @param chr char to pad with -- @param len the total length of the finished string -- @return str string containing the padded string padWithChar = function( str, chr, len ) return str .. string.rep(chr, len - #str) end, } return _ENV;