Irai Erpris Scuriy Ifrasrucur wih Cloud Compui Olivr Pfaff Corpora Tcholoy Sims G 81739 Muich, Grmay Sbasia Ris Corpora Tcholoy Sims G 81739 Muich, Grmay bsrac Tradiioal rpriss hav hir roos i o-prmiss compui. Thy opra scuriy ifrasrucur o-prmis. This icluds corpora usr rposioris, auhicaio ad auhorizaio sysms. This ifrasrucur backs ad abls workforc produciviy. I has o b irad wh uilizi Cloud compui. Hc radiioal rpriss cour spcific iraio challs wih rspc o hir scuriy ifrasrucur wh cosidri Cloud compui. This x aalyss hs challs, idifis bs pracic approachs ad rd-flas commo pifalls. 1. Iroducio Tradiioal rpriss ha cosidr Cloud offris 1 d o ira hir xisi scuriy ifrasrucur spcially corpora usr rposioris, auhicaio as wll as auhorizaio sysms. This ifrasrucur rsids o-prmiss. Is iraio is crucial: h miod o-prmiss scuriy ifrasrucur backs ad abls h produciviy of h workforc of a rpris. Morovr his iraio is courd wih svral yps of applicaios i h Cloud icludi: Ow applicaios dployd o IaaS or PaaS offris 3 rd pary applicaios spcially SaaS offris Th iiial siuaio is show i Fiur 1. Erpris usrs/ hir as I offic or rmo via VPN Erpris usrs/ hir as Rmo, o VPN Fiur 1. Iiial siuaio This iraio ds o b implmd wih car: svral pifalls do xis wh i coms o irai rpris scuriy ifrasrucur wih Cloud compui. Ths pifalls happ o prs a major sourc of complicaio i Cloud adapaio projcs for rpris IT. This x idifis impora scuriy iraio pifalls ad dos labora o hm - spcially hir avoidac/ miiaio. This rsuls i a chcklis ad susios for: pplicaio owrs ad archics: how o dsi applicaios whos dploym modl icluds Cloud ad which shall ira wih xisi scuriy ifrasrucur? Erpris work Ir Scuriy ifrasrucur compos O-prmiss XaaS compos Cloud Srvic owrs, popl i char of scuriy ifrasrucur: how o xpos scuriy ifrasrucur wh Cloud-basd applicaios ar bi addd? Providrs of Cloud-basd srvics: how o addrss h iraio wih scuriy ifrasrucur ha Cloud providrs susai o-prmiss? 1 This x pus a focus o dployms whr XaaS compos rsid ousid h iral work(s). Copyrih 2014, Ifoomics Sociy 338
2. i-pars ai-par is a commo rspos o a rcurri problm ha is usually iffciv ad risks bi hihly courproduciv (cf. hp://.wikipdia.or/wiki/ipar). This x uss his rmioloy o spo commo pifalls i scuriy ifrasrucur iraio. 2.1. XaaS rquirs o-boardi of rpris usrs XaaS offris may rquir rpris usrs o o-board i ordr o us srvics i h Cloud 2. This o-boardi of rpris usrs compasss various implmaio opios such as usr slf-risraio, classical or fdrad provisioi as wll as usr bulk loadi. Issus: Th o-boardi of rpris usrs may lad o h duplicaio of usr idiy iformaio wih rsuli sychroizaio ds. Morovr, auhicaio accou zombis mih b crad. This rfrs o usr accous i h Cloud which ar quippd wih iiial auhicaio crdials (.. passwords) ad ha ar affiliad o h rpris 3. Such objcs bcom criical i cas of lavrs: usually rpriss ar prpard o rcocil hir o-prmiss scuriy ifrasrucur wihi a limid imfram of say 24 hours i cas of vs such as quii. Bu for various rasos hy ar of o wll-prpard o rcocil dpd objcs i xral sysms. This prss a major scuriy risk. Miiaio: Ijc all iformaio abou lod-i usrs by mas of iformaio-rich scuriy ok objcs ha ar cosumd by XaaS compos (cf. ai-par 2.4). void XaaS compos ha dpd o daa for o lod-i usrs rsp. miia his cocr i a adqua way (cf. ai-par 2.7). Cava: XaaS compos which dpd o usr iformaio ha is o availabl i h rpris scuriy ifrasrucur. I paricular his may b courd wih 3 rd pary SaaS offris. Rcommdaio: Limi XaaS usr rposioris o iformaio o availabl i rpris ifrasrucur. XaaS sysms should o cra ow usr rposioris ha duplica iformaio hld i corpora usr rposioris. void sori iiial auhicaio crdials i XaaS usr rposioris. s a Cloud providr, xpos a IdM srvic allowi subscribrs o maa such iformaio. spcs of usr o-boardi aspcs ar illusrad i Fiur 2. This fiur shows criical (duplicad iformaio, crdials) as wll as ucriical (iformaio o availabl i aiv rposioris, idifir for corrlaio purposs) ims. 2 This rfrs o h ovrall rpris usr populaio or lar subpopulaios, o h admiisraors of a Cloud subscripio oly. 3 Usr accou i h Cloud for rpris <X> usr Joh Do (Joh Do@Ta<ErprisX>) Ta <X> @x.com xaasrol @x.com Erpris <X> scuriy ifrasrucur saasdmi Fiur 2. Criical aspcs of usr o-boardi 2.2. XaaS asks for iiial auhicaio crdials Bfor usrs ar rad accss o procd XaaS rsourcs hy d o b auhicad. XaaS compos may implm his by challi for iiial auhicaio crdials by hmslvs. Exampls for such crdials ar: saic passwords, o-im-passwords, scuriy qusios ad aswrs. Thir validaio may happ aais rfrc iformaio ha is sord i aiv rpris ifrasrucur or XaaS offris. Issus: Lack of SSO usr xpric across o-prmiss ad s. Risk of idiy hf i h cas of lo-livd crdials 4. Miiaio: Rai h vrifir rol for iiial auhicaio o-prmiss. Do o xpos crdial validaio fucioaliy 5. Do xpos auhicaio fucioaliy 6. Oly rval iformaio abou auhicaio vs o h Cloud (i form of scuriy oks i.. procd objcs). Cava: umbr of proposals xis o xraliz iiial auhicaio icludi fdrad IdM proocols such as SML, WS-Fdraio ad Ouh/OpID Coc [1], [4], [5], [10]. This rquirs smar choics whr rlyi paris (XaaS compos) ad assri paris (i h rpris ifrasrucur) hav o b i sychroizaio. Rcommdaio: XaaS compos should o ask for iiial auhicaio crdials by hmslvs. If usr auhicaio is dd, XaaS compos should rdirc or dirc 7 o assri paris i h rpris ifrasrucur. 4 Som crdials ar sord i hashd form sp. passwords i LDP. I his cas h oriial crdials (passwords) do o xposd i h backd bu mih hav frod xposur 5 Ipu: idifir, iiial auhicaio crdial Oupu: Boola, (op.) sa iformaio Okay: idifir o corrla aiv ifo Criical: duplicaio Criical: crdial Okay: ifo ha is o availabl aivly Cloud providr ifrasrucur 6 Ipu: auhicaio rqus (wihou iiial auhicaio crdials) Oupu: scuriy ok rpori o iiial auhicaio v 7 Dails dpd o h applicaio proocol ad h yp of usr a. For xampl: i cas of HTTP, XaaS compos should rdirc (HTTP 30x rsposs) i cas of Wb browsrs as usr as (so-calld passiv Copyrih 2014, Ifoomics Sociy 339
Thir duy is o prform usr auhicaio ad rpor o usr auhicaio vs. Iappropria ways of rspodi o o or isufficily auhicad rquss ar skchd for HTTP i Fiur 3. 200 OK <LoiForm> or 401 Uauhorizd WWW-uhica Basic/Dis (hr: prsaio or srvic-orid Wb applicaio) Cloud providr ifrasrucur Fiur 3. Iappropria ways of rspodi o o or isufficily auhicad HTTP rquss 2.3. XaaS dpds o backchal iracios for SSO To provid SSO usr xpric, XaaS compos may dpd o dirc xchas wih srvics providd by h rpris work. Such xchas do o ravrs h usr a. Exampls ar: arifac profil xchas i cas of SML ad UsrIfo srvic xchas i cas of OpID Coc. Th uilizaio of backchal iracios for h purpos of SSO ca b mobil-fridly bcaus i avoids supplyi poially complx scuriy oks across cosraid usr as. Issus: Backchals plac a burd o h rpris. Thy mada o mak crai dpois i h rpris scuriy ifrasrucur public-faci. Miiaio: I is o dd for a assri pary for Wbbasd fdrad SSO o xpos public-faci dpois. Cava: Ohr us cass may rquir backchals ad/or public-faci dpois for usr auhicaio. Exampls ar SLO ad h auhicaio of mploy usrs accssi h rpris ifrasrucur rmoly via public work ifrasrucur oly. Rcommdaio: Provid SSO usr xpric hrouh frod xchas o rduc h xposur of o-prmiss scuriy ifrasrucur 8. XaaS offris should b prpard for hadli fro- ad backchal iracios. Backchal iracios for SSO us cass ar illusrad i Fiur 4. uh srvic 30x Rdirc hps://x.com/auh Erpris <X> scuriy ifrasrucur (hr: prsaio or srvic-orid Wb applicaio) Fiur 4. Backchal iracios for SSO 2.4. XaaS pulls propris of lod-i usrs 401 Uauhorizd WWW-uhica Barr uh cli G auhicad ifo (.. scuriy ok) fr a has auhicad a usr 9, i may wa o look up furhr propris by usr idifir.. usr aribus or affiliaios (rol assims or roup mmbrships). This implis quryi a o-prmiss corpora usr rposiory or usr srvic. Issus: I som cass, issus aris from scuriy oks ha coai oly parial iformaio abou lod-i usrs. I ohr cass, vrsail scuriy oks ar providd bu dowsram cosumrs hoour hir idifir porios oly mawhil hy rquir supplmary usr propris. Miiaio: Cha from pull o push modls wih rspc o h propris of lod-i usrs. Cava: This rquirs iformaio-rich, vrsail scuriy ok objcs s from assri paris i h rpris scuriy ifrasrucur o rlyi paris i XaaS. I also rquirs h coordiaio bw dpois rmiai h fdrad auhicaio proocol o rlyi pary sid ad h acual cosumr of his iformaio.. Wb applicaio i XaaS. Rcommdaio: Ijc iformaio o lod-i usrs as par of h auhicaio ad SSO procss. Do o xpc corpora rposioris o b accssibl for XaaS compos. Pulli propris of lod i usrs is show i Fiur 5. This fiur shows h approach of accssi corpora usr rposioris by aiv mas (which is o b avoidd). @x.com clis) ad dirc (HTTP 401 rsposs) i cas of browsr-basd or mobil apps (so-calld aciv clis). 8 Ulss public-faci dpois ar rquird for ohr rasos such as h suppor of cosraid dvics or clis. 9 By cosumi scuriy oks issud by assri paris ha ar providd as a pary of h rpris scuriy ifrasrucur. Copyrih 2014, Ifoomics Sociy 340
Scuriy ok (lod-i usr ) Erpris <X> scuriy ifrasrucur uh srvic Fiur 5. Pulli propris of lod-i usrs 2.5. XaaS cars for rpris-iiiad loi oly Rposiory cli (hr: prsaio or srvic-orid Wb applicaio) G / for lod-i usr Th fdrad loi mih b implmd i a way ha madas usrs o firs auhica aais h scuriy ifrasrucur of h rpris/rpris bfor accssi ay XaaS offri 10. Issus: Usrs bookmark XaaS rsourcs ad brows from bookmarks. This is o addrssd by rpris-iiiad loi oly ad rsuls i usaisfacory usr xpric. Miiaio: Ev wh h so-calld IdP-iiiad loi prss h dsiad usr xpric, XaaS as wll as rpris scuriy ifrasrucur compos mus b prpard o hadl XaaS-iiiad lois. Cava: Th hadovr of uauhicad rquss from XaaS o rpris scuriy ifrasrucur ds o b prformd i a way ha is raspar o h usrs. Rcommdaio: Suppor XaaS-iiiad as wll as rpris-iiiad usr loi o XaaS compos. 2.6. XaaS dpds o backchal iracios for auhorizaio dcisio maki XaaS compos may iclud PEP compos ha call rmo PDPs for auhorizaio dcisio maki. Th rmo PDP is assumd o b providd as par of h scuriy ifrasrucur of a rpris. This ca b do by mas of.. XCML [8] cox rquss/rsposs. Issus: Prformac ad availabiliy bcom cocrs if XaaS compos irac wih rmo scuriy ifrasrucur for h vas majoriy of rquss. No ha amou as wll as im-criicaliy of raffic bw PEPs ad PDPs (auhorizaio dcisio rquss ad rsposs) usually is @x.com maiuds larr ha bw PDPs ad PPs (auhorizaio policis ad ohr isrucios). Miiaio: lloca PDP compos a XaaS. Supply policy/rul objcs (.. XCML policy objcs) rsp. cofiuraio iformaio (.. rsourc lisis or classificaios) o hm. Cava: Rquirs muually ard sadards for maai h lifcycl of auhorizaio policy objcs. Rcommdaio: Kp auhorizaio dcisio maki local (hr: i h Cloud). If dd: pla for a Cloud-hosd PDP compo which is supplid wih h compay s policy/rul objcs rsp. cofiuraio iformaio. 2.7. XaaS asks for daa of o lod-i usrs Whil procssi rquss of lod-i usrs, XaaS applicaios may d o accss daa of ohr usrs (who may bu do o hav o b lod-i simulaously).. o sd ou oificaios. For furhr dails abou such us cass s [7]. Issus: Erpriss ar usually uwilli o provid accss o hir corpora usr rposioris o clis from h Ir via aiv rposiory proocol mas (.. LDP ad SQL) as his would pu cor asss a risk. Miiaio: Implm ad xpos a ddicad srvic (.. RESTful HTTP srvic accordi SCIM [3]) ha is scuriyabld ad ha provids a façad for quryi h aiv usr rposiory i a spcific ad cosraid fashio 11. s XaaS compo: suppor xralizaio of rposiory clis.. us plu-i irfacs o dploy srvic clis. Cava: XaaS offris ha iraliz or hardcod h usr lookup implmaio by.. implmi aiv rposiory proocols such as LDP or SQL spcially wh his implmaio dos o provid suffici mas of cofiuri h rposiory dpois as wll as cos srucur. Rcommdaio: Cra a ddicad srvic (.. RESTful HTTP srvic) o qury iformaio abou aiv usrs. Closly moior his srvic ad mak sur ha is clis mus risr ad ar auhicad ad auhorizd o a soud lvl. Do o xpos usr rposioris o xral rposiory clis i hir aiv form, i.. via LDP or SQL. Pulli propris of o lod i usrs is show i Fiur 6. This fiur shows h approach of accssi corpora usr rposioris by aiv mas (which is o b avoidd). 10 ka: IdP-iiiad xchas or usolicid rsposs (SML 2.0) 11 Qury rspos cos filrd accordi h approvd ds of h cli rprsi h Copyrih 2014, Ifoomics Sociy 341
Scuriy ok (lod-i usr ) Erpris <X> scuriy ifrasrucur uh srvic Rposiory cli Fiur 6. Pulli propris of o lod-i usrs 2.8. XaaS dpds o backchal iracios for ohr us cass.. audii XaaS compos may sd rquss o o-prmiss rspodrs i ordr o fulfil ohr scuriy-rlad us cass such as h droppi of audii daa. Issus: Iboud rquss o o-prmiss rspodrs ar ypically blockd by a compay s firwall ad would rquir chas o h cofiuraio of h work boudary. Miiaio: Us o-prmiss clis o sablish a (bidircioal) cocio o s (.. WbSock, MQP). fr his has b sablishd, h cli may rciv iformaio from s. Cava: This rquirs addiioal implmaio ffors o sid of h XaaS compos (.. mssa brokrs) ad hir subscribrs. Rcommdaio: Rly o h w call you do call us par of iracio: us o-prmiss clis which sablish (bidircioal) cocios o s. 2.9. XaaS uss propriary Wb SSO proocols Wb applicaios ha ar procd wih Wb SSO as which ar providd by h compay s chos Wb SSO produc shall b movd from iral works o IaaS or PaaS offris i h Cloud. Issus: Naiv SSO schms i may radiioal Wb SSO producs suffr from limid auhicaio rqus xprssivss as wll as o-vrsail scuriy oks. This of rsuls i difficulis wh ryi o implm us cass aroud r-auhicaio as wll as sp-up auhicaio. I coras o applicaios ha rsid o-prmiss such schms bcom a d i ordr o proc public-faci XaaS dpois. Miiaio: bado lacy Wb SSO mchaisms. Swich o sadards-basd Wb SSO proocols. @x.com (hr: prsaio or srvic-orid Wb applicaio) G usr ifo for usr.. Cava: Thr is a plhora of sadards-basd Wb SSO proocols o choos from. Cadidas iclud SML, WS- Fdraio ad Ouh/OpID Coc. Rcommdaio: Us sadards-basd Wb SSO proocols mphasizi o auhicaio rqus xprssivss ad scuriy ok vrsailiy. 2.10. XaaS dos o provid public-faci dpois ccss o XaaS compos mih b limid o compui dvics from h rpris work. Dvics ha rsid ousid h rpris prmiss mus us VPN choloy 12. Issus: Usa of VPNs prss issus for usrs of cosraid compui dvics.. abls or smar-phos. Miiaio: s XaaS compo: suppor browsr-basd clis by xposi public-faci dpois for HTTP ad WbSock by mas of h URL accss schms hps rsp. wss i.. HTTP rsp. WbSock-ovr-SSL/TLS 13. Cava: Public-faci XaaS dpois rquir w mas of procio.. hroli or cox-awar adapiv usr auhicaio icludi mchaisms such as r-auhicaio ad sp-up auhicaio. Corrspodi mchaisms ar ucommo i bhid h firwall -rpris IT. Rcommdaio: Us/cra XaaS offris ha xpos public-faci dpois spcially HTTP ad WbSockovr-SSL/TLS. Esur/implm mas of procio ha xd byod h rpris IT bs curr pracics. 3. Coclusios This x idifid ai-pars of irai xisi rpris scuriy ifrasrucur wih Cloud compui 14. Such ai-pars ar of courd. Thy prs a major sourc of complicaio i Cloud adapaio projcs. Th idifid ai-pars ar rlad o: Commuicaio/work ifrasrucur: ai-pars 2.3, 2.4, 2.8 ad 2.10 uhicaio rposioris/sysms/proocols: aipars 2.1, 2.2, 2.3, 2.5 ad 2.9 ribu/affiliaio rposioris: ai-pars 2.1, 2.4 ad 2.7 uhorizaio sysms: ai-par 2.6 No mar whhr o is crai or susaii a Cloud compui offri or plai o us i as a subscribr, h idifid scuriy ifrasrucur iraio ai-pars ar o b avoidd or a las miiad. This x providd susios o hir avoidac ad miiaio. 12 I coras o h ai-pars abov, i which h iraio of rpris scuriy ifrasrucur imposs challs o h Cloud, his ai-par ariss from ovr-uilizi h rpris s scuriy ifrasrucur. 13 Erpris firwalls ar usually cofiurd o accommoda such ouboud raffic; h dfaul por 443 is usually op for ouboud raffic. 14 S [9] for a ovrviw of idiy-rlad Cloud us cass. Copyrih 2014, Ifoomics Sociy 342
This x did o covr Cloud scuriy cocrs byod h iraio wih xisi rpris scuriy ifrasrucur such as h opraioal scuriy of Cloud offris. ddiioal criria apply o assss h ovrall scuriy of a Cloud providr (cf. [2], [6]). 4. bbrviaios MQP dvacd Mssa Quui Proocol HTTP HyprTx Trasfr Proocol IaaS Ifrasrucur as a Srvic IM Idiy ad ccss Maam IdM Idiy Maam IdP Idiy Providr LDP Lihwih Dircory ccss Proocol Ouh Op uhorizaio PaaS Plaform as a Srvic PP Policy dmiisraio Poi PEP Policy Eforcm Poi PDP Policy Dcisio Poi REST REprsaioal Sa Trasfr SaaS Sofwar as a Srvic SML Scuriy ssrio Markup Laua SCIM Sysm for Cross Domai Idiy Maam SLO Sil Lo-Ou SQL Sadard Qury Laua SSL Scur Socks Layr SSO Sil-Si-O TLS Traspor Layr Scuriy URL Uiform Rsourc Locaor VPN Virual Priva Nwork WS Wb Srvics XaaS y <X> as a Srvic icludi IaaS, PaaS, SaaS XCML Xsibl ccss Corol Markup (hp://www.surf.l/biaris/co/asss/surf//kowldba s/2010/eds-4+provisioi+scarios+i+fdraios+ Fial.pdf) [8] E. Rissa (d.): Xsibl ccss Corol Markup Laua (XCML) Vrsio 3.0. OSIS Sadard, 2013. (hp://docs.oasis-op.or/xacml/3.0/xacml-3.0-cor-spc-os.doc) [9] M. Rukowski (d.): Idiy i h Cloud Us Cass v1.0. OSIS Commi No 2012 (hp://docs.oasis-op.or/id- cloud/idcloud-uscass/v1.0/c01/idcloud-uscass-v1.0- c01.hml) [10] N. Sakimura, J. Bradly, M. Jos, B. d Mdiros ad C. Morimor: OpID Coc Cor 1.0. OpID Foudaio Sadard, 2014. (hp://opid./spcs/opid-coc-cor- 1_0.hml) 5. Rfrcs [1] S. Caor, J. Kmp, R. Philpo ad E. Malr (ds.): ssrios ad Proocols for h OSIS Scuriy ssrio Markup Laua (SML) V2.0, OSIS Sadard, 2005. (hp://docs.oasis-op.or/scuriy/saml/v2.0/saml-cor-2.0- os.pdf) [2] Cloud Scuriy lliac: Scuriy Gac for Criical ras of Focus i Cloud Compui v3.0, 2011. (hps://cloudscuriyalliac.or/ac/csa.v3.0.pdf) [3] T. Drak (d.): Sysm for Cross-Domai Idiy Maam: Proocol. IETF Draf (work-i-pross), 2014. (hps://ools.if.or/hml/draf-if-scim-api-13) [4] M. Goodr ad. Nadali (ds.): Wb Srvics Fdraio Laua (WS-Fdraio) Vrsio 1.2, OSIS Sadard, 2009. (hp://docs.oasis-op.or/wsfd/fdraio/v1.2/os/wsfdraio-1.2-spc-os.hml) [5] D. Hard (d.): Th Ouh 2.0 uhorizaio Framwork, IETF RFC 6749, 2012. (hp://ools.if.or/hml/rfc6749) [6] W. Jas ad T. Grac: Glis o Scuriy ad Privacy i Public Cloud Compui. NIST Spcial Publicaio 800-144, 2011. (hp://csrc.is.ov/publicaios/ispubs/800-144/sp800-144.pdf) [7] M. Oosdijk, B. Hulsbosch, N. va Dijk, R. va Rijswijk ad H. Zadbl: Provisioi scarios i idiy fdraios. Surf Rsarch Papr, 2010. Copyrih 2014, Ifoomics Sociy 343