One document matched: draft-ietf-pkix-lightweight-ocsp-profile-00.txt




 PKIX Working Group                                           A. Deacon 
 Internet Draft                                                VeriSign 
 Category: Informational                                       R. Hurst 
 Document: draft-ietf-pkix-lightweight-ocsp-profile-00.txt    Microsoft 
 Expires: March 2005                                     September 2004
  
                          Lightweight OCSP Profile  
                        for High Volume Environments 
      
 Status of this Memo  
     
    By submitting this Internet-Draft, I certify that any applicable 
    patent or other IPR claims of which I am aware have been disclosed, 
    or will be disclosed, and any of which I become aware will be 
    disclosed,in accordance with RFC 3668. 
     
    Internet-Drafts are working documents of the Internet Engineering 
    Task Force (IETF), its areas, and its working groups.  Note that 
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    The list of current Internet-Drafts can be accessed at  
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    The list of Internet-Draft Shadow Directories can be accessed at 
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 Abstract  
     
    This document defines a lightweight profile of OCSP (RFC 2560) for 
    use in very large PKI environments such as SSL/TLS, code signing 
    and secure messaging.  In these environments there exists a large 
    client base (in the 100's of millions) and thus the ability to 
    scale OCSP request handling is very important. 
   
 Table of Contents 
     
    Introduction.....................................................2 
    1. OCSP Message Profile..........................................2 
       1.1 OCSP Request Profile......................................2 
       1.1.1 OCSPRequest Structure...................................2 
       1.1.2 Signed OCSPRequests.....................................3 
       1.2 OCSP Response Profile.....................................3 
       1.2.1 OCSPResponse Structure..................................3 
  
  
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       1.2.2 Signed OCSPResponses....................................4 
       1.2.3 OCSPResponseStatus Values...............................4 
       1.2.4 thisUpdate, nextUpdate and producedAt...................5 
    2. Client Behavior...............................................5 
       2.1 OCSP Responder Discovery..................................5 
       2.2 Sending an OCSP Request...................................5 
       2.3 OCSP response status processing...........................6 
    3. Ensuring an OCSPResponse is Fresh.............................6 
    4. Transport Profile.............................................7 
    5. Caching Recommendations.......................................8 
       5.1 Caching at the Client.....................................8 
       5.2 HTTP Proxies..............................................8 
       5.3 Caching at Servers.......................................10 
    6. Security Considerations......................................10 
       6.1 Replay attacks...........................................10 
       6.2 Man-in-the-middle attacks................................11 
       6.3 Impersonation attacks....................................11 
       6.4 Denial of service attacks................................11 
       6.5 Modification of HTTP Headers.............................12 
    7. Acknowledgements.............................................12 
    8. References...................................................12 
       8.1 Normative................................................12 
       8.2 Informative..............................................13 
    9. Author's Addresses...........................................13 
    Appendix A. Useful Response Extensions..........................13 
       Appendix A.1. nextPublish Response Extension.................13 
    Appendix B.  Example OCSP Messages..............................14 
       Appendix B.1: OCSP Request...................................14 
       Appendix B.2: OCSP Response..................................14 
        
 Introduction 
     
    This document addresses the OCSP [OCSP] scalability issues inherent 
    in high volume PKI environments by defining an OCSP message profile 
    and OCSP client behavior that will permit: 
     
    1) OCSP response pre-production and distribution 
    2) Reduced OCSP message size to lower bandwidth usage 
    3) Response message caching both in the network and on the client  
  
 1. OCSP Message Profile 
  
    This section defines a subset of OCSPRequest and OCSPResponse 
    functionality as defined in [OCSP]. 
  
 1.1 OCSP Request Profile 
     
 1.1.1 OCSPRequest Structure 
     
  
  
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    OCSPRequests conformant to this profile MUST include only one 
    Request in the OCSPRequest.RequestList structure.   
     
    Clients MUST use SHA1 as the hashing algorithm for the 
    CertID.issuerNameHash and the CertID.issuerKeyHash values. 
     
    Clients MUST NOT include the singleRequestExtensions structure. 
     
    Clients SHOULD NOT include the requestExtensions structure.  If a 
    requestExtensions structure is included, this profile RECOMMENDS 
    that it contain only the nonce extension (id-pkix-ocsp-nonce).  See 
    Section 3 for issues concerning the use of a nonce in high volume 
    OCSP environments. 
     
    1.1.2 Signed OCSPRequests 
     
    Clients SHOULD NOT create or send signed OCSPRequests.  Responders 
    MAY ignore the signature on OCSPRequests. 
     
    If the OCSPRequest is signed, the client SHALL specify its name in 
    the OCSPRequest.requestorName field, otherwise clients SHOULD NOT 
    include the requestorName field in the OCSPRequest. OCSP servers 
    MUST be prepared to receive unsigned OCSP requests that contains 
    the requestorName field, but must realize that the provided value 
    is not authenticated. 
     
    Note: The suggested use of unsigned requests in this environment 
    does not enable a responder to determine the authenticity of 
    incoming request.  Thus, access to the responder is implicitly 
    given to any relying party. 
     
 1.2 OCSP Response Profile 
  
 1.2.1 OCSPResponse Structure 
     
    Responders MUST generate a BasicOCSPResponse as identified by the 
    id-pkix-ocsp-basic OID. Clients MUST be able to parse and accept a 
    BasicOCSPResponse.  OCSPResponses conformant to this profile SHOULD 
    include only one SingleResponse in the ResponseData.responses 
    structure, but MAY include additional SingleResponse elements if 
    necessary to improve response pre-generation performance or cache 
    efficiency. 
     
    The responder SHOULD NOT include responseExtensions. Clients MUST 
    NOT fail if they encounter non-critical responseExtensions in the 
    response.   
     
    In the case a responder does not have the ability to respond to an 
    OCSP request containing a nonce, such as if it only has the ability 
  
  
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    to use pre-produced responses, it SHOULD return a response that 
    does not include a nonce. Clients SHOULD attempt to accept a 
    response even if the response does not include a nonce.  See 
    Section 3 for details on validating responses that do not contain a 
    nonce.  See also Section 6 for relevant security considerations. 
    Responders that do not have the ability to respond to OCSP requests 
    that contain a nonce MAY forward the request to an OCSP responder 
    capable of doing so.   
     
    The responder MAY include the singleResponse extensions structure. 
  
 1.2.2 Signed OCSPResponses 
     
    Responders MUST use the sha1WithRSAEncryption signature algorithm 
    when signing the OCSPResponse.  Clients MUST validate the signature 
    on the returned OCSPResponse. 
     
    If the response is signed by a delegate of the issuing CA the 
    responder certificate MUST be referenced in the 
    BasicOCSPResponse.certs structure.   
     
    The responder's certificate MUST have a validity window greater 
    than or equal to the validity window of the responses it issues.   
     
    It is RECOMMENDED that the OCSP responder's certificate contain the 
    id-ocsp-nocheck EKU OID to indicate to the client that it need not 
    check its status.  In addition, it is RECOMMENDED that neither an 
    OCSP AIA extension nor CDP extension be included in the the OCSP 
    responder's certificate.  Accordingly, the responder's signing 
    certificate SHOULD be relatively short-lived and rolled over 
    regularly. 
     
    Clients MUST be able to identify OCSP responder certificates using 
    both the byName and byKey ResponseData.ResponderID choices.   
    Responders MAY use byKey to further reduce the size of the response 
    in scenarios where reducing bandwidth is an issue. 
     
 1.2.3 OCSPResponseStatus Values 
     
    As long as the responder has records for a particular certificate, 
    an OCSPResponseStatus of "successful" will be returned.   
    In order to ensure the database of revocation information does not 
    grow unbounded over time, the responder MAY remove the status 
    records of expired certificates.    
     
    The responder will return an OCSPResponseStatus of "unauthorized" 
    when processing requests for which it is not capable of responding 
    authoritatively.   
  
  
  
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 1.2.4 thisUpdate, nextUpdate and producedAt 
  
    When pre-producing OCSPResponse messages, the responder MUST set 
    the thisUpdate, nextUpdate and producedAt times as follows: 
  
    thisUpdate    The time at which the status being indicated 
                   is known to be correct. 
    nextUpdate    The time at or before which newer information 
                   will be available about the status of the 
                   certificate.  Responders MUST always include 
                   this value to aid in response caching.  See 
                   Section 5 for additional information on 
                   caching. 
                    
    producedAt    The time at which the OCSP response is signed.  
     
    Note: In many cases the value of thisUpdate and producedAt will be 
    the same. 
     
    For the purposes of this profile, GeneralizedTime values such as 
    thisUpdate, nextUpdate and producedAt MUST be expressed Greenwich 
    Mean Time (Zulu) and MUST include seconds (i.e.,times are 
    YYYYMMDDHHMMSSZ), even where the number of seconds is zero.  
    GeneralizedTime values MUST NOT include fractional seconds. 
     
 2. Client Behavior 
    
 2.1 OCSP Responder Discovery 
     
    Clients MUST support the authorityInfoAccess extension as defined 
    in [PKIX] and MUST recognize the id-ad-ocsp access method.  This 
    enables CAs to inform clients how they can contact the OCSP 
    service. 
     
    In the case where a client is checking the status of a certificate 
    that contains both an authorityInformationAccess extension pointing 
    to a OCSP responder and a cRLDistributionPoints extension pointing 
    to a CRL, the client MUST contact the OCSP responder first.  
    Clients MAY attempt to retrieve the CRL if and only if no 
    OCSPResponse is received from the responder. 
     
 2.2 Sending an OCSP Request 
     
    To avoid needless network traffic, applications MUST verify the 
    signature of signed data before asking an OCSP client to check the 
    status of certificates used to verify the data. If the signature is 
    invalid or the application is not able to verify it, an OCSP check 
    MUST NOT be requested. 
  
  
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    Similarly, applications MUST validate the signature on certificates 
    and its chain, before asking an OCSP client to check the status of 
    the certificate. If the certificate signature is invalid or the 
    application is not able to verify it, an OCSP check MUST NOT be 
    requested.  Clients SHOULD NOT request the status of expired 
    certificates.  
  
 2.3 OCSP response status processing 
  
    OCSP response status 'good': The client MUST inform the calling 
    application that the certificate has not been revoked. 
    The client SHOULD NOT accept an OCSP response that indicates (in 
    the nextUpdate field) that a newer response is available.  See 
    Section 5.1 for details on client caching behavior 
  
    OCSP response status 'revoked': The client MUST inform the calling 
    application that the signature is untrusted and abort any further 
    processing of the signed data. 
     
    OCSP response status 'unknown': The client MUST inform the calling 
    application about the unknown certificate status. This profile 
    RECOMMENDS calling applications to warn the user about the unknown 
    certificate status and give the user the option to continue or 
    abort the processing of the data, with a default option of abort. 
  
     
 3. Ensuring an OCSPResponse is Fresh 
  
    In order to ensure a client does not accept an out of date response 
    that indicates a 'good' status when in fact there is a more up to 
    date response that specifies the status of 'revoked', a client must 
    ensure the responses they receive are fresh.   
     
    In general, two mechanisms are available to clients to ensure a 
    response is fresh.  The first uses nonces, and the second is based 
    on time.  In order for time based mechanisms to work, clients MUST 
    have access to an accurate source of time.   
     
    Because this profile specifies that clients SHOULD NOT include a 
    requestExtensions structure in OCSPRequests (See Section 1.1) 
    clients MUST be able to determine OCSPResponse freshness based on 
    an accurate source of time.  Clients that opt to include a nonce in 
    the request MUST NOT reject a corresponding OCSPResponse solely on 
    the basis of the non-existent expected nonce, but MUST fall back to 
    validating the OCSPResponse based on time.    
     


  
  
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    If a client includes a nonce in an OCSPRequest, and receives a 
    nonce in the corresponding OCSPResponse it MUST ensure that the 
    nonce included in the OCSPRequest matches the nonce received in the 
    OCSPRequest.  If the nonces do not match the client MUST reject the 
    response as invalid.  Clients that do not include a nonce in the 
    request MUST ignore any nonce that may be present in the response.   
     
    If there is no nonce in the OCSPResponse, clients MUST check for 
    the existence of the nextUpdate field.  If the nextUpdate field is 
    absent, and there's no other way for the client to determine the 
    freshness of the response, the client MUST reject the response.   
     
    If the nextUpdate field is present the client MUST ensure that it 
    is not earlier than current time.  If the current local time on the 
    client is later than the time specified in the nextUpdate field, 
    the client MUST reject the response as stale.  Clients MAY allow 
    configuration of a small tolerance period for acceptance of 
    responses after nextUpdate to handle minor clock differences 
    relative to responders and caches.  This tolerance period should be 
    no more than a few minutes to avoid introducing increased security 
    risks. 
     
    See the security considerations in Section 6 for additional details 
    on replay and man-in-the-middle attacks.   
     
 4. Transport Profile 
  
    The OCSP responder MUST support requests and responses over HTTP.  
    When sending requests that are less than 255 bytes in total (after 
    encoding) including the method (http://), server name and base64 
    encoded OCSPReqeust structure, clients MUST use the GET method (to 
    enable for OCSP response caching). OCSP requests larger than 255 
    bytes SHOULD be submitted using the POST method. In all cases, 
    clients MUST follow the descriptions in A.1.1 of [OCSP] when 
    constructing these messages. 
     
    When constructing a GET message, OCSP clients MUST base64 encode 
    the OCSPRequest structure and append it to the URI specified in the 
    AIA extension [PKIX].  Clients MUST NOT include CR or LF characters 
    in the base64-encoded string.  Clients MUST properly url-encode the 
    base64 encoded OCSPRequest, e.g.   
     
      http://ocsp.example.com/MEowSDBGMEQwQjAKBggqhkiG9w0CBQQQ7sp6GTKpL
      2dAdeGaW267owQQqInESWQD0mGeBArSgv%2FBWQIQLJx%2Fg9xF8oySYzol80Mbpg
      %3D%3D 
     
    In response to properly formatted OCSPRequests that do not contain 
    a nonce, the responder will include the binary value of the DER 

  
  
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    encoding of the OCSPResponse preceded by the following HTTP 
    headers. 
     
      content-type=application/ocsp-response 
      content-transfer-encoding=binary 
      content-length=<OCSP response length> 
      last-modified: <producedAt HTTP date> 
      expires: <nextUpdate HTTP date>
      cache-control: max-age=<n>, public, no-transform, must-revalidate 
      date: <current HTTP date> 
     
    See Section 5.2 for details on the use of these headers. 
  
 5. Caching Recommendations 
  
    The ability to cache OCSP Responses throughout the network is an 
    important factor in high volume OCSP deployments.  This section 
    discusses the recommended caching behavior of OCSP clients and HTTP 
    proxies and the steps that should be taken to minimize the number 
    of times that OCSP clients "hit the wire".   In addition the 
    concept of including OCSP responses in protocol exchanges (aka 
    stapling or piggybacking), such as has been defined in TLS, is also 
    discussed.   
     
 5.1 Caching at the Client 
     
    To minimize bandwidth usage, clients MUST locally cache 
    authoritative OCSP responses. (i.e. those who's signature has 
    successfully validated and that indicate an OCSPResponseStatus of 
    'successful')  Once cached, the client SHOULD NOT send a new OCSP 
    request until the nextUpdate time in the cached response.   
     
    Most OCSP clients will send OCSPrequests at or near the nextUpdate 
    time (when the cached response expires). To avoid large spikes in 
    responder load that might occur when many clients refresh cached 
    responses for a popular certificate (e.g. www.bigecommercesite.com), 
    clients MAY use a locally derived value (i.e. 48 hours) to specify 
    a time period before nextUpdate time when a client might consider 
    refreshing its cached response. For example, a client can select a 
    random time between "nextUpdate minus locally configured value" and 
    "nextUpdate" at which to request a refresh of its cached 
    OCSPResponse. 
  
 5.2 HTTP Proxies 
     
    The responder SHOULD set the HTTP headers of the OCSP response in 
    such a way to allow for the intelligent use of intermediate HTTP 
    proxy servers.  

  
  
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    HTTP Header    Description 
    ===========    ==================================================== 
    date           The date and time at which the OCSP server generated 
                   the HTTP response. 
     
    last-modified  This value specifies the date and time at which the 
                   OCSP responder last modified the response.  This 
                   date and time will be the same as the thisUpdate 
                   timestamp in the request itself.   
     
    expires        Specifies how long the response is considered fresh. 
                   This date and time will be the same as the  
                   nextUpdate timestamp in the OCSP response itself.   
     
    cache-control  Contains a number of caching directives. 
       
                   * max-age=<n> - where n is the nextUpdate time 
                                   minus the time the response is 
                                   generated (i.e. the Date header) 
                                   in seconds.  
                   * public -      makes normally uncachable response 
                                   cachable by both shared and 
                                   nonshared caches.   
                   * no-transform -specifies that a proxy cache cannot 
                                   change the type, length , or  
                                   encoding of the object content.   
                   * must-revalidate - prevents caches from 
                                       intentionally returning stale 
                                       responses.  
     
    OCSP responders MUST NOT include a Pragma: no-cache or 
    Cache-Control: no-store header in all OCSP responses.   
  
    For example, assume that an OCSP response has the following time 
    stamp values: 
  
      thisUpdate = May 1, 2003  01:00:00 GMT 
      nextUpdate = May 3, 2003 01:00:00 GMT 
      productedAt = May 1, 2003 01:00:00 GMT 
  
    and that an OCSP client requests the response on May 2, 2003 
    01:00:00 GMT.  In this scenario the HTTP response will look like 
    this: 
  
      content-type: application/ocsp-response 
      content-transfer-encoding: binary 
      content-length: <OCSP response length> 
  
  
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      date: Fri, 02 May 2003 01:00:00 GMT 
      last-modified: Thu, 01 May 2003 01:00:00 GMT 
      expires: Sat, 03 May 2003 01:00:00 GMT 
      cache-control: max-age=86400,public,no-transform,must-revalidate 
      <...> 
       
    If a client encounters an expired response, it may be a result of 
    an intermediate proxy caching stale data, as such clients SHOULD 
    resend the request specifying that proxies should be bypassed by 
    including an appropriate HTTP header in the request (i.e. Pragma: 
    no-cache or Cache-Control: no-store). 
       
 5.3 Caching at Servers 
     
    In some scenarios it is advantageous to include OCSP response 
    information within the protocol being utilized between the client 
    and server.  Including OCSP responses in this manner has a few 
    attractive effects. 
     
    First, it allows for the caching of OCSP responses on the server, 
    thus lowering the number of hits to the OCSP responder. 
     
    Second, it simplifies the client side OCSP implementation by 
    enabling a situation where the client need only the ability to 
    parse and recognize OCSP responses. 
     
    Third, it reduces the number of round trips the client needs to 
    make in order to validate a certificate.   
     
    Fourth, it enables certificate validation in the event the client 
    is not connected to a network and thus eliminates the need for 
    clients to establish a new HTTP session with the responder. 
     
    This functionality has been specified as an extension to the TLS 
    [TLS] protocol in Section 3.6 [TLSEXT], but can be applied to any 
    client-server protocol. 
     
    This profile RECOMMENDS that both TLS clients and servers implement 
    the certificate status request extension mechanism for TLS.  
   
 6. Security Considerations  
     
    The following considerations apply in addition to the security 
    consideration addressed in Section 5 of [OCSP]  
  
 6.1 Replay attacks 
     
    Because the use of nonce's in this profile is optional, there is a 
    possibility that an out of date OCSP response could be replayed, 
  
  
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    thus causing a client to accept good response when in fact there is 
    a more up to date response that specifies the status of revoked.  
    In order to mitigate this attack, clients MUST have access to an 
    accurate source of time and ensure that the OCSP responses they 
    receive are sufficiently fresh.   
     
    Required clock accuracy is relative to the validity duration of the 
    client's OCSP responses.  A client using responses that are good 
    for one hour SHOULD have a clock that is within a few minutes 
    correct time, while a client with 24-hour responses SHOULD be 
    within an hour of correct time. 
     
    Clients that do not have an accurate source of date and time are 
    vulnerable to service disruption due to rejection of fresh OCSP 
    responses.  If this problem is not repaired, a client with a 
    sufficiently slow clock may also incorrectly accept expired 
    responses for currently revoked certificates. 
  
  
 6.2 Man-in-the-middle attacks 
     
    To mitigate risk associated with this class of attack, the client 
    must properly validate the signature on the response.   
     
    The use of signed responses in OCSP serves the purpose to 
    authenticate the identity of the OCSP responder that has authority 
    to sign request on the CA's behalf. 
     
    Clients MUST ensure that they are communicating with an authorized 
    responder by the rules described in [OCSP] Section 4.2.2.2. 
     
 6.3 Impersonation attacks 
     
    The use of signed responses in OCSP serves the purpose to 
    authenticate the identity of OCSP Responder. 
     
    Clients must properly validate the signature of the OCSP response 
    and the signature(s) on the OCSP response signer certificate to 
    ensure an authorized responder created it. 
     
 6.4 Denial of service attacks 
     
    OCSP responders should take measures to prevent or mitigate denial 
    of service attacks. In particular OCSP responders should not 
    perform an unlimited number of resource intensive operations.  
     
    In the case where client requests are not signed, as specified by 
    this profile, OCSP responders should take additional steps to 
    detect an attack of this kind. 
  
  
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    One such technique could be to attempt to match which response to 
    send based on the hash of the request, this would protect against 
    decode related attacks. However since extensions are supported not 
    all requests for the same certificate will be the same as such it 
    would also be necessary to support a full decode based lookup. As 
    such this technique would only help defend against accidental 
    attacks. 
     
 6.5 Modification of HTTP Headers 
  
    Values included in HTTP headers as described in Section 4 and 5, 
    are not cryptographically protected, they may be manipulated by an 
    attacker.  Clients SHOULD use these values for caching guidance 
    only and should ultimately rely on the values present in the signed 
    OCSPResponse.  
     
 7. Acknowledgements 
  
    The authors wish to thank Magnus Nystrom Of RSA Security, Inc., 
    Jagjeet Sondh of Vodafone Group R&D and David Engberg of 
    CoreStreet, Ltd. for their contributions to this specification. 
     
 8. References 
  
 8.1 Normative 
     
    [HTTP]   Fielding, R., Gettys, J., Mogul, J., Frystyk, H., 
             Masinter, L., Leach, P. and T. Berners-Lee, "Hypertext 
             Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. 
  
    [KEYWORDS]  Bradner, S., "Key words for use in RFCs to Indicate 
             Requirement Levels", BCP 14, RFC 2119, March 1997. 
     
    [OCSP]   Myers, M., Ankney, R., Malpani, A., Galperin, S. and 
             C. Adams, "Internet X.509 Public Key Infrastructure: 
             Online Certificate Status Protocol - OCSP", RFC 2560, 
             June 1999. 
     
    [PKIX]   Housley, R., Polk, W., Ford, W. and D. Solo, "Internet 
             Public Key Infrastructure - Certificate and 
             Certificate Revocation List (CRL) Profile", RFC 3280, 
             April 2002. 
     
    [TLS]    Dierks, T. and C. Allen, "The TLS Protocol Version 
             1.0", RFC 2246, January 1999. 
     
    [TLSEXT] Blake-Wilson, et. al., "Transport Layer Security (TLS) 
             Extensions", RFC 3546, June 2003. 
  
  
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 8.2 Informative 
     
    [URI]    Berners-Lee, T., Fielding, R. and L. Masinter, 
             "Uniform Resource Identifiers (URI): Generic Syntax", 
             RFC 2396, August 1998 
     
    [PKIOP]  Housley, R. and P. Hoffman, "Internet X.509 Public Key 
             Infrastructure - Operation Protocols: FTP and HTTP", 
             RFC 2585, May 1999. 
     
    [OCSPMP] "OCSP Mobile Profile", OpenMobileAlliance,  
             www.openmobilalliance.org.   
  
 9. Author's Addresses  
         
    Alex Deacon  
    VeriSign, Inc.  
    487 E. Middlefield Road      Phone:  1-650-426-3478  
    Mountain View, CA. USA       Email:  a1ex@verisign.com  
     
    Ryan Hurst  
    Microsoft  
    One Microsoft Way            Phone:  1-425-707-8979  
    Redmond, WA. USA             Email:  rmh@microsoft.com 
     
     
 Appendix A. Useful Response Extensions 
  
 Appendix A.1. nextPublish Response Extension 
     
    Support for this extension is optional. This extension indicates 
    the time at which the server will be issuing new information about 
    the status of the certificate. If present can be used by the 
    relying party to determine when it is acceptable to begin attempts 
    for new revocationinformation.  
     
    The time specified in the nextPublish extension SHOULD be before 
    the time specified in the nextUpdate field.   
     
    This profile RECOMMENDEDS this value be used by clients to 
    determine when it is possible to check for more up to date 
    information.   
     
       id-msft-nextPublish OBJECT IDENTIFIER ::= {1.3.6.1.4.1.311.21.4} 
     
        nextPublish EXTENSION ::= { 
         SYNTAX          nextPublishSyntax 
         IDENTIFIED BY   id-msft-nextPublish 
  
  
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       } 
     
       nextPublishSyntax ::= Time 
     
       Time ::= CHOICE { 
          utcTime        UTCTime, 
          generalTime    GeneralizedTime  
      } 
     
  
 Appendix B.  Example OCSP Messages 
  
 Appendix B.1: OCSP Request 
     
    SEQUENCE { 
      SEQUENCE { 
        SEQUENCE { 
          SEQUENCE { 
            SEQUENCE { 
              SEQUENCE { 
                OBJECT IDENTIFIER sha1 (1 3 14 3 2 26) 
                NULL 
                } 
              OCTET STRING 
                C0 FE 02 78 FC 99 18 88 91 B3 F2 12 E9 C7 E1 B2 
                1A B7 BF C0 
              OCTET STRING 
                0D FC 1D F0 A9 E0 F0 1C E7 F2 B2 13 17 7E 6F 8D 
                15 7C D4 F6 
              INTEGER 
                6B 26 79 83 A4 9A B7 C2 3D FF 58 E8 81 AA A5 0E 
              } 
            } 
          } 
        } 
      } 
  
 Appendix B.2: OCSP Response 
  
    SEQUENCE { 
       ENUMERATED 0 
       [0] { 
         SEQUENCE { 
           OBJECT IDENTIFIER ocspBasic (1 3 6 1 5 5 7 48 1 1) 
           OCTET STRING, encapsulates { 
             SEQUENCE { 
               SEQUENCE { 
                 [1] { 
                   SEQUENCE { 
  
  
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                        Lightweight OCSP Profile         September 2004 
  
  
                     SET { 
                       SEQUENCE { 
                         OBJECT IDENTIFIER organizationName (2 5 4 10) 
                         PrintableString 'Example, Inc.' 
                         } 
                       } 
                     SET { 
                       SEQUENCE { 
                         OBJECT IDENTIFIER 
                           organizationalUnitName (2 5 4 11) 
                         PrintableString Example Trust Network' 
                         } 
                       } 
                     SET { 
                       SEQUENCE { 
                         OBJECT IDENTIFIER 
                           organizationalUnitName (2 5 4 11) 
                         PrintableString 
                       'Terms of use at https://www.example.com/rpa' 
                       '(c)02' 
                         } 
                       } 
                     SET { 
                       SEQUENCE { 
                         OBJECT IDENTIFIER commonName (2 5 4 3) 
                         PrintableString 
                       'Example Class 3 International Server OCSP' 
                       'Responder' 
                         } 
                       } 
                     } 
                   } 
                 GeneralizedTime 11/09/2003 14:55:57 GMT 
                 SEQUENCE { 
                   SEQUENCE { 
                     SEQUENCE { 
                       SEQUENCE { 
                         OBJECT IDENTIFIER sha1 (1 3 14 3 2 26) 
                         NULL 
                         } 
                       OCTET STRING 
                       C0 FE 02 78 FC 99 18 88 91 B3 F2 12 E9 C7 E1 B2 
                       1A B7 BF C0 
                       OCTET STRING 
                       0D FC 1D F0 A9 E0 F0 1C E7 F2 B2 13 17 7E 6F 8D 
                       15 7C D4 F6 
                       INTEGER 
                       6B 26 79 83 A4 9A B7 C2 3D FF 58 E8 81 AA A5 0E 
                       } 
  
  
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                     [0] 
                       Error: Object has zero length. 
                     GeneralizedTime 11/09/2003 14:55:57 GMT 
                     } 
                   } 
                 } 
               SEQUENCE { 
                 OBJECT IDENTIFIER 
                   sha1withRSAEncryption (1 2 840 113549 1 1 5) 
                 } 
               BIT STRING 
                 17 C3 A3 0B 87 1A A5 C9 39 D2 1E E4 49 9C 84 48 
                 DC E7 9A 68 89 77 BE 25 60 97 D9 FB 8C D0 C5 E8 
                 9B D2 25 F6 52 E9 BA 22 C8 FE C4 B6 B3 9F 1F 71 
                 58 FC BE 39 DC 9D 4E 85 00 8C F1 A9 92 CD 25 CA 
                 3C DC B9 61 46 76 87 BD A1 E9 F6 41 E2 B3 D6 7E 
                 E1 FD A1 5D 2D 08 7C 01 3F 2C 3A 39 60 F1 53 AD 
                 1E 81 E0 57 55 02 F7 D3 FC 9A F8 CA 09 DA 87 1E 
                 8A 93 01 58 E0 31 72 A1 4A 05 F7 3E 21 2F D7 93 
               [0] { 
                 SEQUENCE { 
                   SEQUENCE { 
                     SEQUENCE { 
                       [0] { 
                         INTEGER 2 
                         } 
                       INTEGER 
                       24 D4 27 7D 62 AC 2D 92 F8 D3 4E B1 A5 19 84 78 
                       SEQUENCE { 
                         OBJECT IDENTIFIER 
                           sha1withRSAEncryption (1 2 840 113549 1 1 5) 
                         NULL 
                         } 
                       SEQUENCE { 
                         SET { 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               organizationName (2 5 4 10) 
                             PrintableString "Example Trust Network' 
                             } 
                           } 
                         SET { 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               organizationalUnitName (2 5 4 11) 
                             PrintableString 'Example, Inc.' 
                             } 
                           } 
                         SET { 
  
  
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                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               organizationalUnitName (2 5 4 11) 
                             PrintableString 
                       'Example International Server CA - Class 3' 
                             } 
                           } 
                         } 
                       SEQUENCE { 
                         UTCTime 09/07/2002 00:00:00 GMT 
                         UTCTime 24/10/2011 23:59:59 GMT 
                         } 
                       SEQUENCE { 
                         SET { 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               organizationName (2 5 4 10) 
                             PrintableString 'Example, Inc.' 
                             } 
                           } 
                         SET { 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               organizationalUnitName (2 5 4 11) 
                             PrintableString 'Example Trust Network' 
                             } 
                           } 
                         SET { 
                           SEQUENCE { 
                             OBJECT IDENTIFIER commonName (2 5 4 3) 
                             PrintableString 
                                  'Example OCSP Responder' 
                             } 
                           } 
                         } 
                       SEQUENCE { 
                         SEQUENCE { 
                           OBJECT IDENTIFIER 
                             rsaEncryption (1 2 840 113549 1 1 1) 
                           NULL 
                           } 
                         BIT STRING, encapsulates { 
                           SEQUENCE { 
                             INTEGER 
                       00 CF 50 81 96 9A F5 D8 E2 DE 0B CF A3 A6 FB 46 
                       3E 88 0F 34 0F 5B 28 93 6D 32 EC D1 D0 0B 9B B4 
                       5C 9E 12 F0 22 79 1E 6E 0D C6 39 7E A8 C5 01 A7 
                       9F D8 93 D4 48 61 19 28 9A 93 7F ED 2A C4 CA 2C 
                       E3 47 0C 49 D6 7E D2 FB BC 2C 08 0D 9C FF 05 E6 
  
  
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                       B0 EC 4B 93 1C AF 8E A9 F3 00 07 09 CF 9B 60 F6 
                       ED D1 B9 62 6F F1 A7 D3 61 0A 64 30 93 C9 43 4A 
                       0E 3E A3 3E 47 D7 B2 0D B4 65 53 CC 0A FE CF E5 
                               [ Another 1 bytes skipped ] 
                             INTEGER 65537 
                             } 
                           } 
                         } 
                       [3] { 
                         SEQUENCE { 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               basicConstraints (2 5 29 19) 
                             OCTET STRING, encapsulates { 
                               SEQUENCE {} 
                               } 
                             } 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               certificatePolicies (2 5 29 32) 
                             OCTET STRING, encapsulates { 
                               SEQUENCE { 
                                 SEQUENCE { 
                                   OBJECT IDENTIFIER  
                                           '2 16 840 1 1 1 7 23 3' 
                                   SEQUENCE { 
                                     SEQUENCE { 
                                       OBJECT IDENTIFIER 
                                         cps (1 3 6 1 5 5 7 2 1) 
                                       IA5String 
                                         'https://www.example.com/rpa' 
                                       } 
                                     } 
                                   } 
                                 } 
                               } 
                             } 
                           SEQUENCE { 
                             OBJECT IDENTIFIER extKeyUsage (2 5 29 37) 
                             OCTET STRING, encapsulates { 
                               SEQUENCE { 
                                 OBJECT IDENTIFIER 
                                   ocspSigning (1 3 6 1 5 5 7 3 9) 
                                 } 
                               } 
                             } 
                           SEQUENCE { 
                             OBJECT IDENTIFIER keyUsage (2 5 29 15) 
                             OCTET STRING, encapsulates { 
  
  
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                               BIT STRING 7 unused bits 
                                 '1'B (bit 0) 
                               } 
                             } 
                           SEQUENCE { 
                             OBJECT IDENTIFIER 
                               ocspNoCheck (1 3 6 1 5 5 7 48 1 5) 
                             OCTET STRING, encapsulates { 
                               NULL 
                               } 
                             } 
                           } 
                         } 
                       } 
                     SEQUENCE { 
                       OBJECT IDENTIFIER 
                         sha1withRSAEncryption (1 2 840 113549 1 1 5) 
                       NULL 
                       } 
                     BIT STRING 
                       91 C2 C6 73 75 63 9A 6E A9 A6 F1 4D 99 F6 63 93 
                       83 78 2A DB DE 56 DE 86 B5 9A B5 E7 27 44 35 28 
                       2E F3 62 B4 9F 17 9F 2B 21 31 90 00 B0 86 E3 AE 
                       B6 2C 72 08 9B B8 9D A3 58 61 A8 01 35 8B 3C 6C 
                       6A D4 FF 01 FA E7 25 0D E8 D4 A5 8D 8E DF 3A 39 
                       11 DE 8E 7A 41 BC 56 48 98 A5 06 86 64 4E AD 0F 
                       5B D1 C7 BB 11 57 45 D4 06 F6 FF 3C 7E C5 78 7B 
                       68 C1 B6 71 9D 45 79 1D F7 03 0E 9E 6A 75 24 51 
                     } 
                   } 
                 } 
               } 
             } 
           } 
         } 
       } 
     
     
    Full Copyright Statement 
     
    Copyright (C) The Internet Society 2004.  This document is subject 
    to the rights, licenses and restrictions contained in BCP 78, and 
    except as set forth therein, the authors retain all their rights. 
     
    This document and the information contained herein are provided on 
    an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE 
    REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND 
    THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, 
    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT 
  
  
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                        Lightweight OCSP Profile         September 2004 
  
  
    THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR 
    ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A 
    PARTICULAR PURPOSE. 
     













































  
  
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PAFTECH AB 2003-20262026-04-23 17:36:17