DNS Root Zone DNSSEC Operations - KSK...– The KSK signs the ZSK, ZSK signs DS for TLDs – KSK and ZSK operators are separate organizaons • Trust is a maer for the consumers, not

DNS Root Zone DNSSEC Operations - KSK Ed Lewis| FIRST-TC Auckland, NZ | February 21, 2016 [email protected]

MyMo%va%on

•  ICANNistaskedwithchangingacrucialconfigura%onparameterofDNSsecurity– Weneedtodevelopaplan(workingonit)– Wedon'thaveafixeddateforthechange

•  Inprepara%onforthetask– Weareengagingwithvariousgroupswhomightbeimpactedbytheworkand/ormighthelpusimproveuponourplanningwork

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Agenda

•  BackgroundonDomainNameSystem(DNS)andDNSSecurityExtensions(DNSSEC)

•  InternetCorpora%onforAssignedNamesandNumbers(ICANN)roleinDNSSEC

•  TheprocessofDNSSECValida%on•  ManagingTrustAnchors-ImpactofaKeyRoll

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ForEngineersWhoDon'tLikeProtocols

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WhatistheIPv4addressforwww.nic.tld.?

TheIPv4addressforwww.nic.tld.isW.X.Y.Z

Informa%onSource

Informa%onSource

Informa%onSource

Informa%onSource

IntermediaryIntermediaryIntermediary

WhyisthereDNSSEC?

•  DNSisnot"client-server"– Noend-to-endsessiontoprotect

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RelyingClient Intermediary Informa%on

Source

•  SeeksandAggregatesInforma%on

•  HighlyGullible

DNSSECDesignApproach

•  DigitalSignatures– Acryptographicallyencryptedchecksumissentalongsidethedata

– Asystemofpublickeysisusedtoverify

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DNSSECforThoseWhoDon'tLikeProtocols

WhatistheIPv4addressforwww.nic.tld.?

TheIPv4addressforwww.nic.tld.isW.X.Y.Z

Digitalsignaturebynic.tldcoveringanswer

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Crypto-checkingaSignature

TheIPv4addressforwww.nic.tld.isW.X.Y.Z

Digitalsignaturebynic.tldcoveringanswer

nic.tldKEYZSK

?✔

✖OR

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HowthisWorks(DNS)

TheRoot

TLDOtherTLDs

NIC.TLDOthers.TLD

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TopLevelDomain

HowthisWorks(Scaling)

TheRoot

TLDOtherTLDs

NIC.TLDOthers.TLD

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KeySet

KeySet

KeySet

HowthisWorks(DNSSEC)

TheRoot

TLDOtherTLDs

NIC.TLDOthers.TLD

nic.tldKEYZSKnic.tldKEYKSK

nic.tldDStldKEYZSKtldKEYKSK

tldDSrootKEYZSKrootKEYKSK

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RolesofDNSSECKeys

•  KSK–key-signingkey,signsinternallymanagedkeys–  Internalreferstowhatanadministratormanages

•  ZSK–zone-signingkey,signsotherinternallymanageddata

•  DS–hashofexternalKSK"onelayerdown"– Externalreferstowhomtheadministratordelegatesauthority

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ChainofTrustinOpera%ons

•  TheInternet'sDNSsystemhasaDNSSECsignedRootZone– Since2010– TheKSKsignstheZSK,ZSKsignsDSforTLDs– KSKandZSKoperatorsareseparateorganiza%ons

•  Trustisamagerfortheconsumers,notproducers,todefine– GoalistoreducereliancetojustoneKSK(set)–  Iftheconsumerwantsto"trustjustone"

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RootZoneKSKandZSKOperators

•  ICANNperformsthemanagementoftheRootZoneKSKaspartoffulfillingtheIANAFunc%onsContract–  ThatcontractismanagedbytheUSDepartmentofCommerce'sNa%onalTelecommunica%onsandInforma%onAdministra%on(NTIA)

•  VerisignperformsthemanagementoftheRootZoneZSKaspartoftheirroleastheRootZoneMaintainer

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ICANN'srole,inbrief

•  ICANNmanagestheKSKlifecycle–  CreatetheKSK(hashappenedonce)–  SignwiththeKSK(quarterly)–  ProtecttheKSK(constantly)– DisposeoftheKSK(hasn'thappenedyet)–  andPublicizetheKSK(constantly)

•  Objec%ve:operateinamannertoenabletrust–  SOC3/SysTrust,auditedbythird-party–  (US)FIPS140-2level4cryptographicdevices(HSM)

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ReturningFocustoDNSSEC

•  WithinDNSSECthereis– SigningtheData

•  Addingdigitalsignatures•  Cryptographickeylife%memanagement•  Thisisnotthesubjectofthistalk

– Valida%ngtheData•  Protec%ngtheconsumeroftheanswer•  Assemblingthechainoftrust•  Managing"whoistrusted"

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WhatisValida%on?

•  Whenaresponseisreceived– Checkthedigitalsignature,cryptographicandotherwise(%me,authority,andsoon)

– Checkallsignatures"upthechain"– Onceananswerisvalidated,itcanbecached,used,forwarded

•  Whatisneeded– Atrustanchorisneeded,a"pinned"KSK

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Informa%onSource

Informa%onSource

Informa%onSource

Informa%onSource

IntermediaryIntermediaryIntermediary

WhereisValida%onDone?

•  DNSisnot"client-server"– Noend-to-endsessiontoprotect

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RelyingClient

Inter-mediary

Informa%onSource

•  SeeksandAggregatesInforma%on

•  Validates

Validator

•  MightValidate

Validator

Whyandwhodoes?

•  Whyvalidate?– Lessensthegullibilityoftheintermediaryelements

– Providesatrustablebaseforopera%ons•  Whynot?

– Valida%onimposessomecostonopera%ng– Valida%oncouldraisefalsealarms

•  Haveoperatorsturnedonvalida%on?– Somehave,a"significantminority"

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TrustAnchorManagement

•  Func%onofthevalida%onengine– Keysthatare"pinned"– RootZoneKSKoughttobeoneofthem– TheremaybeotherKSKsets

•  Theremayalsobe"nega%vetrustanchors"– ExperiencesayssomeDNSoperatorsbotchKSKmanagement

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GelngtheRootZoneKSK

•  ThereareafewwaystogetacopyoftheRootZoneKSK– ViaDNS– ViaWeb– ViaDistributedCode– Viaanythingelse–T-shirts,talks,askingsomeone

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GelngtheRootZoneKSKfromDNS

•  '[email protected]'andpulloutthekeywithflags=257

•  Asanonlymethod,thisisn'tverysecure– Convenientbutnotsecure

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AutomatedUpdatesviaDNS

•  "AutomatedSecureUpdatesofDNSSECTrustAnchors"(RFC5011)– Describesaseriesofopera%onalstepstohaveonetrustanchorsafelyintroducethenext

– Lacksneededmanagementhooks

•  Butifconfigura%onsarepushedbyaconfigura%onmanagementtool,thisapproachwon'twork

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GelngtheRootZoneKSKfromWeb

•  Fromhgps://www.iana.org/dnssec– hgps://data.iana.org/root-anchors/root-anchors.xml– OpenPGPsignatureandPKCS7signature

•  Validateviaappropriatepublickeysonthatsite•  Inplacesince2010

– Examiningwaystoimprovewhat'sthere(whilemaintainingbackwardscompa%bility)

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FutureConsidera%ons

•  Anopenworkitem–– What'sthebestwaytopublicizeakeytoawideaudience?

•  Wearerevisi%ngourapproachtopublica%ontoenabletrusttobebuiltonthekey

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RootZoneKSKinToolDistribu%ons

•  Sopwaremaycomewithacopyofthekeyembedded– Configura%onfile

•  ICANNisworkingwithsopwaredevelopersanddistributorstomakesurethisisreliable

•  S%ll,cau%onthatembeddedkeysmaybe"stale"oncekeysarerolled

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Formoreinforma%on

•  Jointhemailinglist– hgps://mm.icann.org/mailman/lis%nfo/root-dnssec-announce

•  FollowonTwiger– Hashtag:#KeyRollover– Follow@ICANNtechforthemostuptodatenews

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