WO2004032416A1 - Cryptographie a cle publique et son cadre d'applications - Google Patents

Cryptographie a cle publique et son cadre d'applications Download PDF

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Publication number
WO2004032416A1
WO2004032416A1 PCT/SG2002/000198 SG0200198W WO2004032416A1 WO 2004032416 A1 WO2004032416 A1 WO 2004032416A1 SG 0200198 W SG0200198 W SG 0200198W WO 2004032416 A1 WO2004032416 A1 WO 2004032416A1
Authority
WO
WIPO (PCT)
Prior art keywords
certificate
identifier
interval
key
public
Prior art date
Application number
PCT/SG2002/000198
Other languages
English (en)
Inventor
Jianying Zhou
Feng Bao
Huijie Robert Deng
Original Assignee
Agency For Science, Technology And Research
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Agency For Science, Technology And Research filed Critical Agency For Science, Technology And Research
Priority to AU2002330834A priority Critical patent/AU2002330834A1/en
Priority to PCT/SG2002/000198 priority patent/WO2004032416A1/fr
Publication of WO2004032416A1 publication Critical patent/WO2004032416A1/fr

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/321—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving a third party or a trusted authority
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3263—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials involving certificates, e.g. public key certificate [PKC] or attribute certificate [AC]; Public key infrastructure [PKI] arrangements

Definitions

  • This invention relates to public key cryptography, more particularly to verification of a public key.
  • Public-key cryptography has been widely used in various security applications since its invention by Diffie and Hellman in 1976.
  • a pair of keys are used: a private key that is kept confidential by a certain party, and a public key that is available to the public.
  • the public key can be used to encrypt a message or to verify a signature while the corresponding private key could be used to decrypt the cipher text or to generate the signature. It is computationally hard to derive the private key from the public key.
  • Digital signature is one of the most important applications of public-key cryptography, and is the fundamental mechanism for authentication and non-repudiation services.
  • the signer can generate a digital signature of a message using his private key.
  • the receiver can check the origin and integrity of the message by verifying the digital signature with the corresponding public key.
  • the signer cannot deny originating the signature since other parties are unable to forge the signature without the private key.
  • the verifier first needs to make sure what
  • X.509 is an industry standard which defines the format of a public-key certificate.
  • the elements of a public-key certificate include the public key of an entity, the entity's
  • the certificate needs to be issued by a trusted third party (TTP) called the certification authority (CA).
  • TTP trusted third party
  • CA certification authority
  • the certificate revocation information will be accessible to public
  • the IETF PKIX Working Group is developing an Internet standard to support an X.509 based public-key infrastructure (PKI) (R. Housley, W. Ford, W. Polk, and D. Solo.
  • PKI public-key infrastructure
  • the PKI provides a framework for services relating to issuing public-key certificates and distributing revocation information. Certificate
  • a method of performing a public/private key operation comprising the steps of: generating a private and public key
  • the public key having a lifetime; selecting a plurality of intervals within the lifetime and a plurality of respective identifiers, each interval being associated with a
  • a trusted third party having a trusted third party generate a public key certificate which includes the public key and a final identifier, the identifiers being selected so that it is
  • a said identifier being provided by a user with any matter signed or otherwise operated upon using the private key in the associated interval to confirm the
  • a user of the private key holds the certificate or the certificate is held in a
  • One or more identifiers or means from which the identifiers are generated may be stored on a remote server with a user wishing to encrypt matter using
  • the private key typically either obtaining the identifier for the current period from the
  • the identifiers are preferably generated by recursive application of a one-way hash
  • the user may obtain a time stamped version of the encrypted matter to be accompanied
  • the identifier and/or the private key may have validity within a time period, the user
  • sending a time of encryption with the encrypted matter and/or each interval may have
  • interval private key associated therewith an interval private key, the interval private keys being each usable
  • interval keys being such that it is relatively easy to derive a later interval key from an
  • a third party operates on the current interval identifier to
  • a third party wishing to confirm the validity of the certificate may request from the user
  • certificate can be derived from the current identifier.
  • the third party may then use the
  • a public key transaction comprising the steps of: generating a public and private key
  • the private key being held by the user and the public key being accessible to a party
  • the certificate including a
  • certificate identifier the identifiers being such that it is relatively easy to derive the
  • a trusted third party comprising a public key, a final identifier and means
  • the plurality of identifiers are selected so that it is relatively easy to derive the final identifier from one of the plurality of identifiers but relatively difficult to derive
  • the identifiers are the product of the recursive application of a one-way hash function to a root.
  • Said means may include a start date and the number and duration of
  • the identifier and said means are preferably integrated into one or more extensions of the certificate, typically in at least one of: a private extension; a
  • the certificate is preferably constituted using
  • the public key and verifier are preferably bound together in a public key certificate, and
  • the certificate once generated may reside with a user of the private key and accompany
  • certificate verifiers can determine whether the certificate is valid without contacting the CA or other trusted third parties.
  • each interval being associated with an identifier and a said interval private
  • the public key and final identifier preferably form part of a public key certificate issued
  • the identifiers may be generated by recursive application of a one-way hash function to
  • a user may send, to a third party, matter encrypted using the private key associated with the current interval, the identifier associated with the
  • a forward-secure digital signature scheme is disclosed in which transactions for validity periods both before, and after the current period remain
  • Figure 1 illustrates certificate expiry date extension using the embodiment of the invention
  • Figure 2 illustrates public key framework
  • Figure 3 illustrates a procedure for validating signatures using a forward secured digital signature scheme
  • Figure 4 illustrates how the embodiment of present invention may be integrated with the X.509 industry standard which defines the format of a public key certificate.
  • a CRL is a time-stamped list of serial numbers or other certificate identifiers for those certificates that have been revoked by a particular CA.
  • the CRL is signed by the relevant CA and made freely available in a public repository. Updates should be issued
  • the required fields identify the CRL issuer, the algorithm used to sign
  • Optional fields include lists of revoked certificates and CRL extensions.
  • the revoked certificate list is optional to support the case where a CA has
  • Certificates revoked by the CA are uniquely identified by the certificate serial number.
  • the date on which the revocation occurred is specified. Additional information may be
  • Certificate Issuer - identifies the certificate issuer associated with an entry in
  • CRL extensions provide methods for associating additional attributes with CRLs.
  • X.509 v2 CRL format also allows communities to define private extensions to carry information unique to those communities. Each extension in a CRL may be designated as critical or non-critical. A CRL validation must fail if it encounters a critical extension which it does not know how to process. However, an unrecognized non-
  • Authority Key Identifier - identifies the public key corresponding to the
  • Delta CRL Indicator - contains the changes between the base CRL and the
  • Issuing Distribution Point - identifies the CRL distribution point for a
  • CRLs may be distributed by exactly the same means as certificates themselves, namely, via untrusted communications and server systems.
  • One limitation of the CRL revocation method is that the time granularity
  • next periodic CRL is issued ⁇ this may be up to one hour, one day, or one week depending on the frequency that the CA issues CRLs.
  • the OCSP is described in M. Myers, R. Ankney, A. Malpani, S. Galperin, and C.
  • the OCSP enables applications to determine the state of an
  • An OCSP client issues a status request to an OCSP responder and
  • the OCSP responder must be one of the following parties.
  • the OCSP responder Upon receipt of a request, the OCSP responder either returns a definitive response, or produces an error message. All definitive response messages should be digitally signed.
  • the response for each of the certificates in a request consists of
  • the certificate status value of a response is defined as follows. “Good” indicates a positive response to the status inquiry. “Revoked” indicates that the certificate has been
  • OCSP clients Prior to accepting a signed response as valid, OCSP clients should confirm that
  • a public-key framework being an embodiment of the invention, that avoids the
  • the certificate verifiers can check the validity without retrieving the revocation information from the
  • CA This is based on the security building block of a "one-way hash chain”.
  • a one-way hash chain is constructed by recursively applying an input string to a one-
  • r is the root of the hash chain. According to the feature of one-way hash function, if r is chosen randomly and the hash chain is kept secret, given H r), it is computationally
  • a one-way hash chain has been used in some applications including one-time password authentication and micro-payment.
  • certificate includes matter signed by a private key associated with a further public key which has a public key certificate issued by a trusted third party, the validity of which
  • hash chain value is provided in the CRL.
  • the certificate will be initially not valid for use when issued by the CA. Only when the certificate owner releases a chained hash value, will it be valid for a limited time from the starting valid date. The certificate owner extends the expiry date of his certificate by releasing the chained hash values at a
  • refreshing the certificate validity can be defined as short as desired by the certificate owner, so that there is no need of certificate revocation during that interval.
  • a user U's public-key certificate with an extensible expiry date is generated in the following way.
  • U generates a pair of keys: private key SKy and public key PKu.
  • U defines the maximum life time of the key pair (SK U5 PKy) as T, and the
  • Dj D+L
  • D 2 D+2*L
  • the CA authenticates U's request for a certificate in an out-of-band method.
  • the CA sends CERTu to U.
  • CERTu contains extra data (H j (r), j,
  • N verifies the CA's signature on (U, PK U5 D, H j (r), j, L). If true, N will be sure that U's public key is PKy.
  • the starting valid date is D
  • the refreshing time.period is L
  • the one-way hash chain is H j (r).
  • H'(r) is a valid hash value in the one-way hash chain ended with H j (r).
  • N checks that D v ⁇ D + (j-i)*L. If true, N concludes that CERTu is valid
  • N can check the validity of CERTu without
  • certificate revocation can be
  • the random number r serving as the root of the one-way hash chain is critical to the
  • the certificate owner U relies on it to
  • r the length of r could be as short as 20 bytes. As r must be random, it might be a bit hard for an ordinary user to memorize a 20-byte random string. Such a
  • the hash chain root r could be protected with a password.
  • the encrypted r is stored in the local computer system. When CERTy needs to be refreshed, the password is input
  • the length of the password could be as short as 8 bytes. As a password is usually not truly random and an off-line dictionary attack is also possible, this mechanism for
  • the hash chain root r is be encrypted and stored locally while the secret
  • U and the security server can establish a secure and authenticated channel with password-based protocols (S. Bellovin and M. Merritt.
  • This architecture is shown for users U t _K - U n K in Fig. 2 and is especially good for corporate clients in which a security server will centrally manage the secret key for each client. As the security server only needs to serve its internal clients, its connection to the
  • the hash chain root r is generated by the certificate owner U.
  • a public-key certificate may have to be revoked by the manager of the certificate owner for other reasons such as termination of
  • the hash chain root may be generated by a security server SS_r,
  • U generates a pair of keys: private key SK y and public key PKy.
  • the security server defines the
  • the security server selects a random number r
  • the security server sends U's public key PK Us the starting valid date D, the
  • the CA authenticates the security server's request for generating a public-
  • the CA may further challenge U in an out-of-band method to ensure U holds
  • the CA sends CERTu to the security server.
  • the security server forwards CERTy to U.
  • the security server distributes the corresponding
  • the security server can do so by stopping release of U's hash
  • the security server's role in this embodiment is fundamentally different from the CA's
  • a user or his manager can control the validity of his public-key certificate and others can check the validity of such a certificate without
  • Authentication is a basic security service that provides protection against masquerade.
  • This consists of entity authentication that verifies a claimed identity, and data origin
  • Digital signature is an
  • signature verifier will use the signer's public key to verify the signature. More
  • the verifier should check whether the signer's public key is valid at the
  • the signer's public key is usually bound to the signer's identity in a public-key
  • N on ly needs to check whether H'(r) is the hash value that extends the expiry date of CERTy to D e . If so, N can use CERTu safely before its current expiry date D e to verify U's signatures.
  • Non-repudiation is another basic security service that provides protection against false
  • stamp D g on ⁇ denoted as SIGN TSA (D g , ⁇ )
  • SIGN TSA time-stamping authority
  • V holds the TSA's public verification key. Then, V could use
  • V could accept SIGN TSA (D g , ⁇ ), (H(r), i), CERTu safely as valid non-
  • U could further extend the expiry date of CERT ⁇ to D e +L by releasing (H l (r), i-l) when
  • This approach avoids the CA's involvement for certificate revocation. However, it still relies on the trusted third party TSA to provide the time-stamping service.
  • a forward-secure digital signature approach is more efficient as it avoids the
  • the certificate preserve the validity of past signatures without using a trusted time-
  • FWKG for key generation
  • FWUPD for private key update
  • FWSIGN for key generation
  • FWKG generates the public key PK and the
  • the lifetime T is divided into j intervals as before, each interval k of length L being associated with a value of the hash chain H k (r), PK will be certificated
  • Each interval I has also associated therewith an
  • FWUPD is a one-way function in the sense that no one
  • interval private keys SK are arranged such that an earlier interval key cannot be derived from a later one and the hash values are arranged so that a later
  • interval hash value cannot be derived from an earlier one. Used together, the interval
  • private key and interval hash value can relate to one interval only and since it is not possible to derive both a later hash value and a later private key or both an earlier hash
  • the CA will not provide
  • the user sends the encrypted message to the intended recipient.
  • X.509 is an industry standard which defines the format of a public-key certificate
  • the X.509 v3 certificate basic syntax includes version number, serial number, issuer's
  • extension id and the extension value may be designated as critical or non-critical.
  • the X.509 v3 certificate format also allows communities to define private
  • the second option is "subject key id".
  • the subject key id extension provides a means of identifying certificates that contain a particular public key.
  • As the hash chain root r is
  • the data (H j (r), j, L) could be regarded as a subject key identifier that uniquely links to the public key.
  • the third option is "subject alternative name”.
  • the subject alternative name extension allows additional identities to be bound to the subject of the certificate.

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  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Storage Device Security (AREA)

Abstract

L'invention concerne un procédé de réalisation d'une opération à clé publique/privée consistant à : générer une paire de clés privée et publique, la clé publique ayant une durée de vie ; sélectionner une pluralité d'intervalles compris dans la durée de vie et une pluralité d'identificateurs respectifs, chaque intervalle étant associé audit identificateur ; et faire en sorte qu'un tiers de confiance génère un certificat de clé publique comprenant la clé publique et un identificateur final, les identificateurs étant sélectionnés de manière à rendre relativement difficile l'opération d'obtention d'un identificateur associé audit intervalle à partir de l'identificateur final mais à faciliter l'obtention de l'identificateur final à partir d'un identificateur associé audit intervalle. Ledit identificateur est apporté par un utilisateur dont tout sujet est signé ou mis en oeuvre après l'utilisation de la clé privée dans l'intervalle associé afin de confirmer la validité du certificat dans cet intervalle. Un plan de signature numérique sécurisée, au cours duquel les transactions pour des périodes de validité avant et après la période actuelle sont sûres même si la clé privée pour la période actuelle est déjà engagée.
PCT/SG2002/000198 2002-08-30 2002-08-30 Cryptographie a cle publique et son cadre d'applications WO2004032416A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU2002330834A AU2002330834A1 (en) 2002-08-30 2002-08-30 Public key cryptography and a framework therefor
PCT/SG2002/000198 WO2004032416A1 (fr) 2002-08-30 2002-08-30 Cryptographie a cle publique et son cadre d'applications

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/SG2002/000198 WO2004032416A1 (fr) 2002-08-30 2002-08-30 Cryptographie a cle publique et son cadre d'applications

Publications (1)

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WO2004032416A1 true WO2004032416A1 (fr) 2004-04-15

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Cited By (15)

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EP1769605A1 (fr) * 2004-07-20 2007-04-04 Ricoh Company, Ltd. Appareil et procede de controle, systeme de communication, programme informatique et support d'enregistrement lisible par ordinateur
EP1912147A1 (fr) * 2006-10-10 2008-04-16 NTT DoCoMo, Inc. Procédé et appareil de vente d'une ressource numérique
JP2009065326A (ja) * 2007-09-05 2009-03-26 Kddi Corp 暗号化鍵の更新システム、暗号化鍵の更新方法およびプログラム
KR100970552B1 (ko) 2008-06-30 2010-07-16 경희대학교 산학협력단 비인증서 공개키를 사용하는 보안키 생성 방법
US7774602B2 (en) 2004-12-30 2010-08-10 Bce Inc. Secure modem gateway concentrator
US7930412B2 (en) 2003-09-30 2011-04-19 Bce Inc. System and method for secure access
CN102769530A (zh) * 2012-07-02 2012-11-07 赵运磊 一种计算高效的在线/离线数字签名方法
US8577036B2 (en) 2008-04-09 2013-11-05 Siemens Aktiengesellschaft Method and device for transmitting messages in real time
CN105376050A (zh) * 2015-12-24 2016-03-02 鲁东大学 数字证书签名方法及其签名方案
US10277567B2 (en) 2016-06-06 2019-04-30 Motorola Solutions, Inc. Method and server for issuing cryptographic keys to communication devices
US10333935B2 (en) 2016-06-06 2019-06-25 Motorola Solutions, Inc. Method and management server for revoking group server identifiers of compromised group servers
US10341107B2 (en) * 2016-06-06 2019-07-02 Motorola Solutions, Inc. Method, server, and communication device for updating identity-based cryptographic private keys of compromised communication devices
CN112911545A (zh) * 2021-01-29 2021-06-04 暨南大学 一种SAGIVNs中兼顾信任管理和隐私保护的紧急消息散播方法及系统
CN113298522A (zh) * 2021-05-26 2021-08-24 杭州安恒信息技术股份有限公司 一种闪电网络密钥管理方法、装置、电子设备及存储介质
US11405187B2 (en) 2020-04-29 2022-08-02 International Business Machines Corporation Extended-life asymmetric cryptographic key scheme

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CN101977193B (zh) * 2010-10-28 2013-11-13 飞天诚信科技股份有限公司 安全下载证书的方法及系统

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Cited By (20)

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Publication number Priority date Publication date Assignee Title
US8762726B2 (en) 2003-09-30 2014-06-24 Bce Inc. System and method for secure access
US7930412B2 (en) 2003-09-30 2011-04-19 Bce Inc. System and method for secure access
EP1769605A1 (fr) * 2004-07-20 2007-04-04 Ricoh Company, Ltd. Appareil et procede de controle, systeme de communication, programme informatique et support d'enregistrement lisible par ordinateur
EP1769605A4 (fr) * 2004-07-20 2014-01-08 Ricoh Co Ltd Appareil et procede de controle, systeme de communication, programme informatique et support d'enregistrement lisible par ordinateur
US7774602B2 (en) 2004-12-30 2010-08-10 Bce Inc. Secure modem gateway concentrator
US8312279B2 (en) 2004-12-30 2012-11-13 Bce Inc. Secure modem gateway concentrator
EP1912147A1 (fr) * 2006-10-10 2008-04-16 NTT DoCoMo, Inc. Procédé et appareil de vente d'une ressource numérique
JP2009065326A (ja) * 2007-09-05 2009-03-26 Kddi Corp 暗号化鍵の更新システム、暗号化鍵の更新方法およびプログラム
US8577036B2 (en) 2008-04-09 2013-11-05 Siemens Aktiengesellschaft Method and device for transmitting messages in real time
KR100970552B1 (ko) 2008-06-30 2010-07-16 경희대학교 산학협력단 비인증서 공개키를 사용하는 보안키 생성 방법
CN102769530A (zh) * 2012-07-02 2012-11-07 赵运磊 一种计算高效的在线/离线数字签名方法
CN105376050A (zh) * 2015-12-24 2016-03-02 鲁东大学 数字证书签名方法及其签名方案
US10333935B2 (en) 2016-06-06 2019-06-25 Motorola Solutions, Inc. Method and management server for revoking group server identifiers of compromised group servers
US10277567B2 (en) 2016-06-06 2019-04-30 Motorola Solutions, Inc. Method and server for issuing cryptographic keys to communication devices
US10341107B2 (en) * 2016-06-06 2019-07-02 Motorola Solutions, Inc. Method, server, and communication device for updating identity-based cryptographic private keys of compromised communication devices
US11405187B2 (en) 2020-04-29 2022-08-02 International Business Machines Corporation Extended-life asymmetric cryptographic key scheme
CN112911545A (zh) * 2021-01-29 2021-06-04 暨南大学 一种SAGIVNs中兼顾信任管理和隐私保护的紧急消息散播方法及系统
CN112911545B (zh) * 2021-01-29 2022-04-12 暨南大学 一种SAGIVNs中兼顾信任管理和隐私保护的紧急消息散播方法及系统
CN113298522A (zh) * 2021-05-26 2021-08-24 杭州安恒信息技术股份有限公司 一种闪电网络密钥管理方法、装置、电子设备及存储介质
CN113298522B (zh) * 2021-05-26 2023-03-14 杭州安恒信息技术股份有限公司 一种闪电网络密钥管理方法、装置、电子设备及存储介质

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