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Versions: (draft-hoyer-keyprov-portable-symmetric-key-container) 00 01 02 03 04 05 06 draft-ietf-keyprov-pskc

keyprov                                                         P. Hoyer
Internet-Draft                                             ActivIdentity
Intended status: Standards Track                                  M. Pei
Expires: October 23, 2008                                       VeriSign
                                                              S. Machani
                                                              Diversinet
                                                          April 21, 2008


                    Portable Symmetric Key Container
       draft-ietf-keyprov-portable-symmetric-key-container-04.txt

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
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   This Internet-Draft will expire on October 23, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2008).











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Abstract

   This document specifies a symmetric key format for transport and
   provisioning of symmetric keys (for example One Time Password (OTP)
   shared secrets or symmetric cryptographic keys) to different types of
   crypto modules such as a strong authentication device.  The standard
   key transport format enables enterprises to deploy best-of-breed
   solutions combining components from different vendors into the same
   infrastructure.

   This work is a joint effort by the members of OATH (Initiative for
   Open AuTHentication) to specify a format that can be freely
   distributed to the technical community.  The authors believe that a
   common and shared specification will facilitate adoption of two-
   factor authentication on the Internet by enabling interoperability
   between commercial and open-source implementations.



































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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  6
     2.1.  Key Words  . . . . . . . . . . . . . . . . . . . . . . . .  6
     2.2.  Definitions  . . . . . . . . . . . . . . . . . . . . . . .  6
   3.  Use Cases  . . . . . . . . . . . . . . . . . . . . . . . . . .  8
     3.1.  Online Use Cases . . . . . . . . . . . . . . . . . . . . .  8
       3.1.1.  Transport of keys from Server to Crypto Module . . . .  8
       3.1.2.  Transport of keys from Crypto Module to Crypto
               Module . . . . . . . . . . . . . . . . . . . . . . . .  8
       3.1.3.  Transport of keys from Crypto Module to Server . . . .  9
       3.1.4.  Server to server Bulk import/export of keys  . . . . .  9
     3.2.  Offline Use Cases  . . . . . . . . . . . . . . . . . . . .  9
       3.2.1.  Server to server Bulk import/export of keys  . . . . .  9
   4.  Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 11
   5.  Portable Key container definition  . . . . . . . . . . . . . . 13
     5.1.  KeyContainer . . . . . . . . . . . . . . . . . . . . . . . 13
     5.2.  Device . . . . . . . . . . . . . . . . . . . . . . . . . . 15
       5.2.1.  DeviceId . . . . . . . . . . . . . . . . . . . . . . . 15
     5.3.  KeyProperties  . . . . . . . . . . . . . . . . . . . . . . 16
     5.4.  Key  . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
       5.4.1.  Data (OPTIONAL)  . . . . . . . . . . . . . . . . . . . 20
       5.4.2.  Usage (MANDATORY)  . . . . . . . . . . . . . . . . . . 21
       5.4.3.  ValueFormat  . . . . . . . . . . . . . . . . . . . . . 25
       5.4.4.  PINPolicy  . . . . . . . . . . . . . . . . . . . . . . 26
   6.  Usage and profile of algorithms for the portable symmetric
       key container  . . . . . . . . . . . . . . . . . . . . . . . . 28
     6.1.  Usage of EncryptionKey to protect keys in transit  . . . . 28
       6.1.1.  Protecting keys using a pre-shared key via
               symmetric algorithms . . . . . . . . . . . . . . . . . 28
       6.1.2.  Protecting keys using passphrase based encryption
               keys . . . . . . . . . . . . . . . . . . . . . . . . . 29
     6.2.  Protecting keys using asymmetric algorithms  . . . . . . . 31
     6.3.  Profile of Key Algorithm . . . . . . . . . . . . . . . . . 32
       6.3.1.  OTP Key Algorithm Identifiers  . . . . . . . . . . . . 33
       6.3.2.  PIN key value compare algorithm identifier . . . . . . 33
   7.  Reserved data attribute names  . . . . . . . . . . . . . . . . 34
   8.  Formal Syntax  . . . . . . . . . . . . . . . . . . . . . . . . 35
   9.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 40
     9.1.  Content-type registration for 'application/pskc+xml' . . . 40
     9.2.  XML Schema Registration  . . . . . . . . . . . . . . . . . 41
     9.3.  URN Sub-Namespace Registration for
           urn:ietf:params:xml:ns:keyprov:container:1.0 . . . . . . . 41
     9.4.  Symmetric Key Algorithm Identifier Registry  . . . . . . . 42
       9.4.1.  Applicability  . . . . . . . . . . . . . . . . . . . . 42
       9.4.2.  Registerable Algorithms  . . . . . . . . . . . . . . . 43
       9.4.3.  Registration Procedures  . . . . . . . . . . . . . . . 44



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       9.4.4.  Initial Values . . . . . . . . . . . . . . . . . . . . 46
     9.5.  XML Data Tag Identifier Registry . . . . . . . . . . . . . 49
       9.5.1.  Applicability  . . . . . . . . . . . . . . . . . . . . 49
       9.5.2.  Registerable Data Tags . . . . . . . . . . . . . . . . 50
       9.5.3.  Registration Procedures  . . . . . . . . . . . . . . . 50
       9.5.4.  Initial Values . . . . . . . . . . . . . . . . . . . . 51
   10. Security Considerations  . . . . . . . . . . . . . . . . . . . 53
     10.1. Payload confidentiality  . . . . . . . . . . . . . . . . . 53
     10.2. Payload integrity  . . . . . . . . . . . . . . . . . . . . 54
     10.3. Payload authenticity . . . . . . . . . . . . . . . . . . . 54
   11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 55
   12. Appendix A - Example Symmetric Key Containers  . . . . . . . . 56
     12.1. Symmetric Key Container with a single Non-Encrypted
           HOTP Secret Key  . . . . . . . . . . . . . . . . . . . . . 56
     12.2. Symmetric Key Container with a single PIN protected
           Non-Encrypted HOTP Secret Key  . . . . . . . . . . . . . . 56
     12.3. Symmetric Key Container with a single AES-256-CBC
           Encrypted HOTP Secret Key  . . . . . . . . . . . . . . . . 57
     12.4. Symmetric Key Container with signature and a single
           Password-based Encrypted HOTP Secret Key . . . . . . . . . 58
     12.5. Symmetric Key Container with a single RSA 1.5
           Encrypted HOTP Secret Key  . . . . . . . . . . . . . . . . 60
   13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 62
     13.1. Normative References . . . . . . . . . . . . . . . . . . . 62
     13.2. Informative References . . . . . . . . . . . . . . . . . . 62
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 64
   Intellectual Property and Copyright Statements . . . . . . . . . . 65
























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1.  Introduction

   With increasing use of symmetric key based authentication systems
   such as systems based one time password (OTP) and challenge response
   mechanisms, there is a need for vendor interoperability and a
   standard format for importing, exporting or provisioning symmetric
   keys from one system to another.  Traditionally authentication server
   vendors and service providers have used proprietary formats for
   importing, exporting and provisioning these keys into their systems
   making it hard to use tokens from vendor A with a server from vendor
   B.

   This Internet draft describes a standard format for serializing
   symmetric keys such as OTP shared secrets for system import, export
   or network/protocol transport.  The goal is that the format will
   facilitate dynamic provisioning and transfer of a symmetric keys such
   as an OTP shared secret or an encryption key of different types.  In
   the case of OTP shared secrets, the format will facilitate dynamic
   provisioning using an online provisioning protocol to different
   flavors of embedded tokens or allow customers to import new or
   existing tokens in batch or single instances into a compliant system.

   This draft also specifies the key attributes required for computation
   such as the initial event counter used in the HOTP algorithm [HOTP].
   It is also applicable for other time-based or proprietary algorithms.

   To provide an analogy, in public key environments the PKCS#12 format
   [PKCS12] is commonly used for importing and exporting private keys
   and certificates between systems.  In the environments outlined in
   this document where OTP keys may be transported directly down to
   smartcards or devices with limited computing capabilities, a format
   with small (size in bytes) and explicit shared secret configuration
   attribute information is desirable, avoiding complexity of PKCS#12.
   For example, one would have to use opaque data within PKCS#12 to
   carry shared secret attributes used for OTP calculations, whereas a
   more explicit attribute schema definition is better for
   interoperability and efficiency.














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2.  Terminology

2.1.  Key Words

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.2.  Definitions

   This section defines terms used in this document.  The same terms may
   be defined differently in other documents.

   Authentication Token:  A physical device that an authorized user of
      computer services is given to aid in authentication.  The term may
      also refer to software tokens.

   Bulk Provisioning:  Transferring multiple keys linked to multiple
      devices in a single execution step within one single PSKC
      KeyContainer

   Cryptographic Module:  A component of an application, which enables
      symmetric key cryptographic functionality

   Cryptographic Key:  A parameter used in conjunction with a
      cryptographic algorithm that determines its operation in such a
      way that an entity with knowledge of the key can reproduce or
      reverse the operation, while an entity without knowledge of the
      key cannot (see [NIST-SP800-57])

   Cryptographic Token:  See Authentication Token

   Device:  A physical piece of hardware, or a software framework, that
      hosts symmetric keys

   Device ID (DeviceId):  A unique identifier for the device,
      representing the identifying criteria to uniquely identify a
      device

   Dynamic Provisioning:  Usage of a protocol, such as DSKPP, to make a
      key container available to a recipient

   Encryption Key:  A key used to encrypt key

   Key:  See Cryptographic Key






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   Hardware Token:  See Authentication Token

   Key Algorithm:  A well-defined computational procedure that takes
      variable inputs including a cryptographic key and produces an
      output.

   Key Container:  An object that encapsulates symmetric keys and their
      attributes for set of devices

   Key ID (KeyID):  A unique identifier for the symmetric key

   Key Issuer:  An organization that issues symmetric keys to end-users

   Key Type:  The type of symmetric key cryptographic methods for which
      the key will be used (e.g., OATH HOTP or RSA SecurID
      authentication, AES encryption, etc.)

   Secret Key:  The symmetric key data

   Software Token:  A type of authentication token that is stored on a
      general-purpose electronic device such as a desktop computer,
      laptop, PDA, or mobile phone

   Token:  See Authentication Token

   User:  The person or client to whom devices are issued

   User ID:  A unique identifier for the user or client























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3.  Use Cases

   This section describes a comprehensive list of use cases that
   inspired the development of this specification.  These requirements
   were used to derive the primary requirement that drove the design.
   These requirements are covered in the next section.

   These use cases also help in understanding the applicability of this
   specification to real world situations.

3.1.  Online Use Cases

   This section describes the use cases related to provisioning the keys
   using an online provisioning protocol such as [DSKPP]

3.1.1.  Transport of keys from Server to Crypto Module

   For example, a mobile device user wants to obtain a symmetric key for
   use with a cryptomodule on the device.  The cryptomodule client from
   vendor A initiates the provisioning process against a provisioning
   system from vendor B using a standards-based provisioning protocol
   such as [DSKPP].  The provisioning entity delivers one or more keys
   in a standard format that can be processed by the mobile device.

   For example, in a variation of the above, instead of the user's
   mobile phone, a key is provisioned in the user's soft token
   application on a laptop using a network-based online protocol.  As
   before, the provisioning system delivers a key in a standard format
   that can be processed by the soft token on the PC.

   For example, the end-user or the key issuer wants to update or
   configure an existing key in the cryptomodule and requests a
   replacement key container.  The container may or may not include a
   new key and may include new or updated key attributes such as a new
   counter value in HOTP key case, a modified response format or length,
   a new friendly name, etc.

3.1.2.  Transport of keys from Crypto Module to Crypto Module

   For example, a user wants to transport a key from one cryptomodule to
   another.  There may be two cryptographic modules, one on a computer
   one on a mobile phone, and the user wants to transport a key from the
   computer to the mobile phone.  The user can export the key and
   related data in a standard format for input into the other
   cryptomodule.






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3.1.3.  Transport of keys from Crypto Module to Server

   For example, a user wants to activate and use a new key and related
   data against a validation system that is not aware of this key.  This
   key may be embedded in the cryptomodule (e.g.  SD card, USB drive)
   that the user has purchased at the local electronics retailer.  Along
   with the cryptomodule, the user may get the key on a CD or a floppy
   in a standard format.  The user can now upload via a secure online
   channel or import this key and related data into the new validation
   system and start using the key.

3.1.4.  Server to server Bulk import/export of keys

   From time to time, a key management system may be required to import
   or export keys in bulk from one entity to another.

   For example, instead of importing keys from a manufacturer using a
   file, a validation server may download the keys using an online
   protocol.  The keys can be downloaded in a standard format that can
   be processed by a validation system.

   For example, in a variation of the above, an OTA key provisioning
   gateway that provisions keys to mobile phones may obtain key material
   from a key issuer using an online protocol.  The keys are delivered
   in a standard format that can be processed by the key provisioning
   gateway and subsequently sent to the end-user's mobile phone.

3.2.  Offline Use Cases

   This section describes the use cases relating to offline transport of
   keys from one system to another, using some form of export and import
   model.

3.2.1.  Server to server Bulk import/export of keys

   For example, crypto modules such as OTP authentication tokens, may
   have their symmetric keys initialized during the manufacturing
   process in bulk, requiring copies of the keys and algorithm data to
   be loaded into the authentication system through a file on portable
   media.  The manufacturer provides the keys and related data in the
   form of a file containing records in standard format, typically on a
   CD.  Note that the token manufacturer and the vendor for the
   validation system may be the same or different.  Some crypto modules
   will allow local PIN management (the device will have a PIN pad)
   hence random initial PINs set at manufacturing should be transmitted
   together with the respective keys they protect.

   For example, an enterprise wants to port keys and related data from



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   an existing validation system A into a different validation system B.
   The existing validation system provides the enterprise with a
   functionality that enables export of keys and related data (e.g. for
   OTP authentication tokens) in a standard format.  Since the OTP
   tokens are in the standard format, the enterprise can import the
   token records into the new validation system B and start using the
   existing tokens.  Note that the vendors for the two validation
   systems may be the same or different.











































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4.  Requirements

   This section outlines the most relevant requirements that are the
   basis of this work.  Several of the requirements were derived from
   use cases described above.

   R1:   The format MUST support transport of multiple types of
         symmetric keys and related attributes for algorithms including
         HOTP, other OTP, challenge-response, etc.

   R2:   The format MUST handle the symmetric key itself as well of
         attributes that are typically associated with symmetric keys.
         Some of these attributes may be

         *  Unique Key Identifier

         *  Issuer information

         *  Algorithm ID

         *  Algorithm mode

         *  Issuer Name

         *  Key friendly name

         *  Event counter value (moving factor for OTP algorithms)

         *  Time value

   R3:   The format SHOULD support both offline and online scenarios.
         That is it should be serializable to a file as well as it
         should be possible to use this format in online provisioning
         protocols such as [DSKPP]

   R4:   The format SHOULD allow bulk representation of symmetric keys

   R5:   The format SHOULD allow bulk representation of PINs related to
         specific keys

   R6:   The format SHOULD be portable to various platforms.
         Furthermore, it SHOULD be computationally efficient to process.

   R7:   The format MUST provide appropriate level of security in terms
         of data encryption and data integrity.






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   R8:   For online scenarios the format SHOULD NOT rely on transport
         level security (e.g., SSL/TLS) for core security requirements.

   R9:   The format SHOULD be extensible.  It SHOULD enable extension
         points allowing vendors to specify additional attributes in the
         future.

   R10:  The format SHOULD allow for distribution of key derivation data
         without the actual symmetric key itself.  This is to support
         symmetric key management schemes that rely on key derivation
         algorithms based on a pre-placed master key.  The key
         derivation data typically consists of a reference to the key,
         rather than the key value itself.

   R11:  The format SHOULD allow for additional lifecycle management
         operations such as counter resynchronization.  Such processes
         require confidentiality between client and server, thus could
         use a common secure container format, without the transfer of
         key material.

   R12:  The format MUST support the use of pre-shared symmetric keys to
         ensure confidentiality of sensitive data elements.

   R13:  The format MUST support a password-based encryption (PBE)
         [PKCS5] scheme to ensure security of sensitive data elements.
         This is a widely used method for various provisioning
         scenarios.

   R14:  The format SHOULD support asymmetric encryption algorithms such
         as RSA to ensure end-to-end security of sensitive data
         elements.  This is to support scenarios where a pre-set shared
         encryption key is difficult to use.



















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5.  Portable Key container definition

   The portable key container is based on an XML schema definition and
   contains the following main entities:

   1.  KeyContainer entity as defined in Section 5.1

   2.  Device entity as defined in Section 5.2

   3.  Key entity as defined in Section 5.4

   Additionally other XML schema types have been defined and are
   detailed in the relevant subsections of this document

   A KeyContainer MAY contain one or more Device entities.  A Device MAY
   contain one or more Key entities

   The figure below indicates a possible relationship diagram of a
   container.

   --------------------------------------------
   | KeyContainer                             |
   |                                          |
   |  ------------------   -----------------  |
   |  | Device 1       |   | Device n      |  |
   |  |                |   |               |  |
   |  |  ------------  |   | ------------  |  |
   |  |  | Key 1    |  |   | | Key n    |  |  |
   |  |  ------------  |   | ------------  |  |
   |  |                |   |               |  |
   |  |                |   |               |  |
   |  |  ------------  |   | ------------  |  |
   |  |  | Key m    |  |   | | Key p    |  |  |
   |  |  ------------  |   | ------------  |  |
   |  ------------------   -----------------  |
   |                                          |
   --------------------------------------------

   The following section describe in detail all the entities and related
   XML schema elements and attributes:

5.1.  KeyContainer

   The KeyContainer represents the key container entity.  A Container
   MAY contain more than one Device entity; each Device entity MAY
   contain more than one Key entity.

   The KeyContainer is defined as follows:



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 <xs:complexType name="KeyContainerType">
         <xs:sequence>
                 <xs:element name="EncryptionKey"
                         type="ds:KeyInfoType" minOccurs="0"/>
                         <xs:element name="MACAlgorithm"
                         type="pskc:KeyAlgorithmType" minOccurs="0"/>
                         <xs:element name="Device"
                         type="pskc:DeviceType" maxOccurs="unbounded"/>
                 <xs:element name="Signature"
                         type="ds:SignatureType" minOccurs="0"/>
         </xs:sequence>
   <xs:attribute name="Version" type="pskc:VersionType" use="required"/>
 </xs:complexType>

   The elements of the KeyContainer have the following meanings:

   o  <EncryptionKey (OPTIONAL)>, Identifies the encryption key,
      algorithm and possible parameters used to protect the Secret Key
      data in the container.  Please see Section 6.1 for detailed
      description of how to protect key data in transit and the usage of
      this element.

   o  <MACAlgorithm (OPTIONAL)>, Identifies the algorithm used to
      generate a keyed digest of the the Secret Key data values when
      protection algorithms are used that do not have integrity checks.
      The digest guarantees the integrity and the authenticity of the
      key data. for profile and usage please see Section 6.1.1

   o  <Device>, the host Device for one or more Keys as defined in
      Section 5.2 The KeyContainer MAY contain multiple Device data
      elements, allowing for bulk provisioning of multiple devices each
      containing multiple keys.

   o  <Signature (OPTIONAL)>, the signature value of the Container.
      When the signature is applied to the entire container, it MUST use
      XML Signature methods as defined in [XMLDSIG].  It MAY be omitted
      when application layer provisioning or transport layer
      provisioning protocols provide the integrity and authenticity of
      the payload between the sender and the recipient of the container.
      When required, this specification recommends using a symmetric key
      based signature with the same key used in the encryption of the
      secret key data.  The signature is enveloped.

   o  <Version (MANDATORY)>, the version number for the portable key
      container format (the XML schema defined in this document).






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5.2.  Device

   The Device represents the Device entity in the Container.  A Device
   MAY be bound to a user and MAY contain more than one keys.  A key
   SHOULD be bound to only one Device.

   The Device is defined as follows:


<xs:complexType name="DeviceType">
  <xs:sequence>
    <xs:element name="DeviceId" type="pskc:DeviceIdType" minOccurs="0"/>
    <xs:element name="Key" type="pskc:KeyType" maxOccurs="unbounded"/>
    <xs:element name="UserId" type="xs:string" minOccurs="0"/>
  </xs:sequence>
</xs:complexType>

   The elements of the Device have the following meanings:

   o  <DeviceId>, a unique identifier for the device, defined in
      Section 5.2.1

   o  <Key>, represents the key entity as defined in Section 5.4

   o  <UserId>, optionally identifies the owner or the user of the
      Device, a string representation of a Distinguished Name as defined
      in [RFC4514].  For example UID=jsmith,DC=example,DC=net.  In
      systems where unique user Ids are used the string representation
      'UID=[uniqueId]' MUST be used.

5.2.1.  DeviceId

   The DeviceId represents the identifying criteria to uniquely identify
   the device that contains the associated keys.  Since devices can come
   in different form factors such as hardware tokens, smart-cards, soft
   tokens in a mobile phone or PC etc this element allows different
   criteria to be used.  Combined though the criteria MUST uniquely
   identify the device.  For example for hardware tokens the combination
   of SerialNo and Manufacturer will uniquely identify a device but not
   SerialNo alone since two different token manufacturers might issue
   devices with the same serial number (similar to the IssuerDN and
   serial number of a certificate).  Symmetric Keys used in the payment
   industry are usually stored on Integrated Circuit Smart Cards.  These
   cards are uniquely identified via the Primary Account Number (PAN,
   the long number printed on the front of the card) and an expiry date
   of the card.  DeviceId is an extensible type that allows all these
   different ways to uniquely identify a specific key containing device.




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   The DeviceId is defined as follows:


   <xs:complexType name="DeviceIdType">
   <xs:sequence>
       <xs:element name="Manufacturer" type="xs:string"/>
       <xs:element name="SerialNo" type="xs:string"/>
       <xs:element name="Model" type="xs:string" minOccurs="0"/>
       <xs:element name="IssueNo" type="xs:string" minOccurs="0"/>
       <xs:element name="ExpiryDate" type="xs:dateTime" minOccurs="0"/>
       <xs:element name="StartDate" type="xs:dateTime" minOccurs="0"/>
   </xs:sequence>
   </xs:complexType>

   The elements of DeviceId have the following meanings:

   o  <Manufacturer>, the manufacturer of the device.

   o  <SerialNo>, the serial number of the device or the PAN (primary
      account number) in case of payment smart cards.

   o  <Model>, the model of the device (e.g one-button-HOTP-token-V1)

   o  <IssueNo>, the issue number in case of smart cards with the same
      PAN, equivalent to a PSN (PAN Sequence Number).

   o  <ExpiryDate>, the expiry date of a device (such as the one on a
      payment card,used when issue numbers are not printed on cards).

   o  <StartDate>, the start date of a device (such as the one on a
      payment card,used when issue numbers are not printed on cards).

5.3.  KeyProperties

   The KeyProperties represents common properties shared by more than
   one key held in the container.  If a value is set in the properties
   the Key element can refer to it via KeyPropertiesId attribute.
   Values that are present in the Key element itself MUST take
   precendence over values set in KeyProperties.  The KeyProperties is
   defined as follows:











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   <xs:complexType name="KeyPropertiesType">
           <xs:sequence>
                   <xs:element name="Issuer" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="Usage" type="pskc:UsageType"
                   minOccurs="0"/>
                   <xs:element name="KeyProfileId" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="MasterKeyId" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="Data" type="pskc:DataType"
                   minOccurs="0" maxOccurs="unbounded"/>
                   <xs:element name="PINPolicy"
                   type="pskc:PINPolicyType" minOccurs="0"/>
                   <xs:element name="ExpiryDate"
                   type="xs:dateTime" minOccurs="0"/>
                   <xs:element name="StartDate" type="xs:dateTime"
                   minOccurs="0"/>
           </xs:sequence>
           <xs:attribute name="KeyPropertiesId" type="xs:string"
           use="required"/>
           <xs:attribute name="KeyAlgorithm"
           type="pskc:KeyAlgorithmType" use="optional"/>
   </xs:complexType>

   The attributes of the KeyProperties entity have the following
   meanings:

   o  KeyPropertiesId (MANDATORY), a unique and global identifier of set
      of KeyProperties.  The identifier is defined as a string of
      alphanumeric characters.

   o  <KeyAlgorithm (OPTIONAL)>, the unique URI of the type of algorithm
      to use with the secret key, for profiles are described in
      Section 6.3

   Since KeyProperties are a method to commonalise the elements in Key
   please refer to section Section 5.4 for detailed description of all
   elements.

5.4.  Key

   The Key represents the key entity in the KeyContainer.  The Key is
   defined as follows:







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   <xs:complexType name="KeyType">
           <xs:sequence>
                   <xs:element name="Issuer" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="Usage" type="pskc:UsageType"
                   minOccurs="0"/>
                   <xs:element name="KeyProfileId" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="MasterKeyId" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="FriendlyName" type="xs:string"
                   minOccurs="0"/>
                   <xs:element name="Data" type="pskc:DataType"
                   minOccurs="0" maxOccurs="unbounded"/>
                   <xs:element name="PINPolicy"
                   type="pskc:PINPolicyType" minOccurs="0"/>
                   <xs:element name="ExpiryDate" type="xs:dateTime"
                   minOccurs="0"/>
                   <xs:element name="StartDate" type="xs:dateTime"
                   minOccurs="0"/>
           </xs:sequence>
           <xs:attribute name="KeyId" type="xs:string"
           use="required"/>
           <xs:attribute name="KeyAlgorithm"
           type="pskc:KeyAlgorithmType" use="optional"/>
           <xs:attribute name="KeyPropertiesId" type="xs:string"
           use="optional"/>
   </xs:complexType>


   The attributes of the Key entity have the following meanings:

   o  KeyId (MANDATORY), a unique and global identifier of the symmetric
      key.  The identifier is defined as a string of alphanumeric
      characters.

   o  <KeyAlgorithm (OPTIONAL)>, the unique URI of the type of algorithm
      to use with the secret key, for profiles are described in
      Section 6.3

   o  <KeyPropertiesId (OPTIONAL)>, the unique id of the KeyProperties
      whose value the instance of this key inherits.  If this value is
      set implementation MUST lookup the Keyproperties element referred
      to by this unique Id and this instance of key will inherit all
      values from the KeyProperties.  Values held in the key instance it
      MUST take precedence over values inherited from KeyProperties."/>

   The elements of the Key entity have the following meanings:



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   o  <Issuer (OPTIONAL)>, The key issuer name, this is normally the
      name of the organization that issues the key to the end user of
      the key.  For example MyBank issuing hardware tokens to their
      retail banking users 'MyBank' would be the issuer.  The Issuer is
      defined as a String.

   o  <Usage (MANDATORY)>, defines the intended usage of the key and
      related metadata as defined in Section 5.4.2

   o  <KeyProfileId (OPTIONAL)>, A unique identifier used between the
      sending and receiving party of the container to establish a set of
      constant values related to a key that are not transmitted via the
      container.  For example a smart card application personalisation
      profile id related to attributes present on a smart card
      application that have influence when computing a response.  An
      example could be an EMV MasterCard CAP [CAP] application on a card
      personalised with data for a specific batch of cards such as:

         IAF Internet authentication flag

         CVN Cryptogram version number, for example (MCHIP2, MCHIP4,
         VISA 13, VISA14)

         AIP (Application Interchange Profile), 2 bytes

         TVR Terminal Verification Result, 5 bytes

         CVR The card verification result

         AmountOther

         TransactionDate

         TerminalCountryCode

         TransactionCurrencyCode

         AmountAuthorised

         IIPB

      These values are not contained within attributes in the container
      but are shared between the manufacturing and the validation
      service through this unique KeyProfileId.  The KeyProfileId is
      defined as a String.

   o  <MasterKeyId (OPTIONAL)>, The unique reference to a master key
      when key derivation schemes are used and no specific key is



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      transported but only the reference to the master key used to
      derive a specific key and some derivation data.

   o  <FriendlyName (OPTIONAL)>, The user friendly name that is assigned
      to the secret key for easy reference.  The FriendlyName is defined
      as a String.

   o  <Data (OPTIONAL)>, the element carrying the data related to the
      key as defined in Section 5.4.1

   o  <PINPolicy (OPTIONAL)>, the policy of the PIN relating to the
      usage of this key as defined in Section 5.4.4

   o  <ExpiryDate (OPTIONAL)>, the expiry date of the key, it MUST not
      be possible to use this key after this date

   o  <StartDate (OPTIONAL)>, the start date of the key, it MUST not be
      possible to use this key before this date

5.4.1.  Data (OPTIONAL)

   Defines the data attributes of the symmetric key.  Each is a name
   value pair which has either a plain value (in case of no encryption)
   or a encrypted value as defined in EncryptedDataType in XML
   Encryption.

   This is also where the key value is transported, Section 7 defines a
   list of reserved attribute names.

   Data element is defined as follows:


<xs:complexType name="DataType">
    <xs:sequence>
    <xs:choice>
       <xs:element name="PlainValue" type="xs:base64Binary"/>
       <xs:element name="EncryptedValue" type="xenc:EncryptedDataType"/>
    </xs:choice>
    <xs:element name="ValueMAC" type="xs:base64Binary" minOccurs="0"/>
    </xs:sequence>
    <xs:attribute name="Name" type="xs:string" use="required"/>
</xs:complexType>

   The attributes of the Data element have the following meanings:

   o  Name, defines the name of the name-value pair, Section 7 defines a
      list of reserved attribute names




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   The elements of the Data element have the following meanings:

   o  The <PlainValue> conveys an unencrypted value of the name-value
      pair in base 64 encoding.

   o  The <EncryptedValue> element in the DataType conveys an encrypted
      value of the name-value pair inside an EncryptedDataType as
      defined in XML Encryption.

   o  The <ValueMAC (OPTIONAL)> element in the DataType conveys a keyed
      MAC value of the unencrypted data for the cases where the
      algorithm to protect key data in transit, as described in section
      Section 6.1.1 ,does not support integrity checks.

5.4.2.  Usage (MANDATORY)

   The Usage element defines the usage attribute(s) of the key entity.
   Usage is defined as follows:

































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   <xs:complexType name="UsageType">
           <xs:sequence>
                   <xs:element name="ChallengeFormat" minOccurs="0">
                           <xs:complexType>
                             <xs:attribute name="Format"
                             type="pskc:ValueFormatType"
                             use="required"/>
                             <xs:attribute name="Min"
                             type="xs:unsignedInt" use="required"/>
                             <xs:attribute name="Max"
                             type="xs:unsignedInt" use="required"/>
                             <xs:attribute name="CheckDigits"
                             type="xs:boolean" default="false"/>
                           </xs:complexType>
                   </xs:element>
                   <xs:element name="ResponseFormat">
                           <xs:complexType>
                             <xs:attribute name="Format"
                             type="pskc:ValueFormatType"
                             use="required"/>
                             <xs:attribute name="Length"
                             type="xs:unsignedInt" use="required"/>
                             <xs:attribute name="CheckDigits"
                             type="xs:boolean" default="false"/>
                           </xs:complexType>
                   </xs:element>
           </xs:sequence>
           <xs:attribute name="OTP" type="xs:boolean"
           default="false"/>
           <xs:attribute name="CR" type="xs:boolean"
           default="false"/>
           <xs:attribute name="Integrity" type="xs:boolean"
           default="false"/>
           <xs:attribute name="Encrypt" type="xs:boolean"
           default="false"/>
           <xs:attribute name="Unlock" type="xs:boolean"
           default="false"/>
   </xs:complexType>

   The attributes of the Usage element define the intended usage of the
   key and are a combination of one or more of the following (set to
   true):

   o  OTP, the key will be used for OTP generation

   o  CR, the key will be used for Challenge/Response purposes





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   o  Encrypt, the key will be used for data encryption purposes

   o  Integrity, the key will be used to generate a keyed message digest
      for data integrity or authentication purposes.

   o  Unlock, the key will be used for an inverse challenge response in
      the case a user has locked the device by entering a wrong PIN too
      many times (for devices with PIN-input capability)

5.4.2.1.  OTP and CR specific Usage elements (OPTIONAL)

   When the intended usage of a key usage is OTP and/or CR, the
   following additional elements MUST be provided within the Usage
   element to support the OTP and/or the response computation as
   required by the underlying algorithm.  These elements also allow to
   customize or configure the result of the computation (e.g. format,
   length).

5.4.2.1.1.  ChallengeFormat element (MANDATORY)

   The ChallengeFormat element defines the characteristics of the
   challenge in a CR usage scenario.  The Challenge element is defined
   by the following attributes:

   o  Format (MANDATORY)

         Defines the format of the challenge accepted by the device and
         MUST be one of the values defined in Section 5.4.3

   o  CheckDigit (OPTIONAL)

         Defines if the device needs to check the appended Luhn check
         digit contained in a provided challenge.  This is only valid if
         the Format attribute is 'DECIMAL'.  Value MUST be:

            TRUE device will check the appended Luhn check digit in a
            provided challenge

            FALSE device will not check appended Luhn check digit in
            challenge

   o  Min (MANDATORY)

         Defines the minimum size of the challenge accepted by the
         device for CR mode.






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         If the Format attribute is 'DECIMAL', 'HEXADECIMAL' or
         'ALPHANUMERIC' this value indicates the minimum number of
         digits/characters.

         If the Format attribute is 'BASE64' or 'BINARY', this value
         indicates the minimum number of bytes of the unencoded value.

         Value MUST be:



            Unsigned integer.

   o  Max (MANDATORY)

         Defines the maximum size of the challenge accepted by the
         device for CR mode.

         If the Format attribute is 'DECIMAL', 'HEXADECIMAL' or
         'ALPHANUMERIC' this value indicates the maximum number of
         digits/characters.

         If the Format attribute is 'BASE64' or 'BINARY', this value
         indicates the maximum number of bytes of the unencoded value.

         Value MUST be:



            Unsigned integer.

5.4.2.1.2.  ResponseFormat element (MANDATORY)

   The ResponseFormat element defines the characteristics of the result
   of a computation.  This defines the format of the OTP or of the
   response to a challenge.  The Response attribute is defined by the
   following attributes:

   o  Format (MANDATORY)

         Defines the format of the response generated by the device and
         MUST be one of the values defined in Section 5.4.3

   o  CheckDigit (OPTIONAL)







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         Defines if the device needs to append a Luhn check digit to the
         response.  This is only valid if the Format attribute is
         'DECIMAL'.  Value MUST be:

            TRUE device will append a Luhn check digit to the response.

            FALSE device will not append a Luhn check digit to the
            response.

   o  Length (MANDATORY)

         Defines the length of the response generated by the device.

         If the Format attribute is 'DECIMAL', 'HEXADECIMAL' or
         'ALPHANUMERIC' this value indicates the number of digits/
         characters.

         If the Format attribute is 'BASE64' or 'BINARY', this value
         indicates the number of bytes of the unencoded value.

         Value MUST be:



            Unsigned integer.

5.4.3.  ValueFormat

   The ValueFormat element defines allowed formats for challenges or
   responses in OTP algorithms.

   ValueFormat is defined as follows:


   <simpleType name="ValueFormat">
     <restriction base="string">
       <enumeration value="DECIMAL"/>
       <enumeration value="HEXADECIMAL"/>
       <enumeration value="ALPHANUMERIC"/>
       <enumeration value="BASE64"/>
       <enumeration value="BINARY"/>
     </restriction>
   </simpleType>








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      DECIMAL Only numerical digits

      HEXADECIMAL Hexadecimal response

      ALPHANUMERIC All letters and numbers (case sensitive)

      BASE64 Base 64 encoded

      BINARY Binary data, this is mainly used in case of connected
      devices

5.4.4.  PINPolicy

   The PINPolicy element provides a mean to define how the usage of a
   specific key is protected by a PIN.  The PIN itself can be
   transmitted as a key using the container.

   If the PINPolicy element is present in the Key element then the key
   is protected with a PIN as defined within the PINPolicy element.

   PINPolicy is defined as follows:


  <xs:complexType name="PINPolicyType">
      <xs:sequence>
          <xs:element name="PINUsageMode" type="pskc:PINUsageModeType"/>
          <xs:element name="WrongPINtry" type="xs:unsignedInt"
            minOccurs="0"/>
      </xs:sequence>
      <xs:attribute name="PINKeyId" type="xs:string" use="required"/>
  </xs:complexType>

   The attributes of PINPolicy have the following meaning

   o  PINKeyId, the unique key Id within this container that contains
      the value of the PIN that protects the key

   The elements of PINPolicy have the following meaning

   o  <PINUsageMode (MANDATORY)> , the way the PIN is used during the
      usage of the key as defined in Section 5.4.4.1

   o  <WrongPINtry (OPTIONAL)>, the number of times the PIN can be
      entered wrongly before it MUST not be possible to use the key
      anymore






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5.4.4.1.  PINUsageMode

   The PINUsageMode element defines how the PIN is used with a specific
   key

   PINUsageMode is defined as follows:


   <xs:complexType name="PINUsageModeType">
       <xs:choice maxOccurs="unbounded">
           <xs:element name="Local"/>
           <xs:element name="Prepend"/>
           <xs:element name="InAlgo"/>
       </xs:choice>
   </xs:complexType>

   The elements of PINPolicy have the following meaning

   o  <Local>, the PIN is checked locally on the device before allowing
      the key to be used in executing the algorithm

   o  <Prepend>, the PIN is prepended to the OTP or response hance it
      MUST be chacked by the validation server

   o  <InAlgo>, the PIN is used as part of the algorithm computation


























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6.  Usage and profile of algorithms for the portable symmetric key
    container

   This section details the use of the XML encryption and XML signature
   elements to protect the keys transported in the cotainer.  It also
   profiles the number of algorithms supported by XML encryption and XML
   signature to a mandatory subset for interoperability.

   When no algorithm is provided the values within the container are
   unencrypted, implementations SHALL ensure the privacy of the key data
   through other standard mechanisms e.g. transport level encryption.

6.1.  Usage of EncryptionKey to protect keys in transit

   The EncryptionKey element in the KeyContainer defines the key,
   algorithm and parameters used to encrypt the Secret Key data
   attributes in the Container.  The standard schema [XMLENC] is adopted
   in carry such information and an encrypted value.  The encryption is
   applied on each individual Secret Key data in the Container.  The
   encryption method MUST be the same for all Secret Key data in the
   container.

   The following sections define specifically the different supported
   means to protect the keys:

6.1.1.  Protecting keys using a pre-shared key via symmetric algorithms

   When protecting the payload with pre-shared keys implementations
   SHOULD set the name of the specific pre-shared key in the KeyName
   element of the EncryptionKey of the KeyContainer.  For example:


   <KeyContainer Version="1.0"
     xmlns="urn:ietf:params:xml:ns:keyprov:container:1.0"
     xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
     xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
       <EncryptionKey>
           <ds:KeyName>PRE_SHARED_KEY</ds:KeyName>
       </EncryptionKey>
       ....

   The following is the list of symmetric key encryption algorithm and
   possible parameters used to protect the Secret Key data in the
   container.  Systems implementing PSKC MUST support the MANDATORY
   algorithms detailed below.

   The encryption algorithm URI can be one of the following.




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   o  http://www.w3.org/2001/04/xmlenc#tripledes-cbc - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#aes128-cbc - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#aes192-cbc - OPTIONAL

   o  http://www.w3.org/2001/04/xmlenc#aes256-cbc - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#kw-tripledes - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#kw-aes128 - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#kw-aes256 - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#kw-aes512 - OPTIONAL

   When algorithms without integrity checks are used (e.g.
   http://www.w3.org/2001/04/xmlenc#aes256-cbc) a keyed MAC value using
   the same key as the encryption key SHOULD be placed in the ValueMAC
   element of the Data element.  In this case the MAC algorithm type
   MUST be set in the MACAlgorithm element in the key container entity
   as defined in Section 5.1.  Implementations of PSKC MUST support the
   MANDATORY MAC algorithms detailed below.  The MACAlgorithm URI can be
   one of the following:

   o  http://www.w3.org/2000/09/xmldsig#hmac-sha1 - MANDATORY

   For example:


   <KeyContainer Version="1.0"
     xmlns="urn:ietf:params:xml:ns:keyprov:container:1.0"
     xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
     xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
       <EncryptionKey>
           <ds:KeyName>PRE_SHARED_KEY</ds:KeyName>
       </EncryptionKey>
       <MACAlgorithm>http://www.w3.org/2000/09/xmldsig#hmac-sha1
       </MACAlgorithm>
       .....

6.1.2.  Protecting keys using passphrase based encryption keys

   To be able to support passphrase based encryption keys as defined in
   PKCS#5 the following XML representation of the PBE relates parameters
   have been introduced in the schema.  Although the approach is
   extensible implementations of PSKC MUST support the
   KeyDerivationMethod algorithm URI of



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   http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5#pbkdf2.


   <xs:complexType name="DerivedKeyType">
       <xs:sequence>
           <xs:element name="KeyDerivationMethod"
             type="pskc:KeyDerivationMethodType" minOccurs="0"/>
           <xs:element ref="xenc:ReferenceList" minOccurs="0"/>
           <xs:element name="CarriedKeyName" type="xs:string"
             minOccurs="0"/>
       </xs:sequence>
       <xs:attribute name="Id" type="xs:ID" use="optional"/>
       <xs:attribute name="Type" type="xs:anyURI" use="optional"/>
       </xs:complexType>
       <xs:complexType name="KeyDerivationMethodType">
       <xs:sequence>
               <xs:any namespace="##other" minOccurs="0"
                 maxOccurs="unbounded"/>
       </xs:sequence>
       <xs:attribute name="Algorithm" type="xs:anyURI"
       use="required"/>
   </xs:complexType>

   The attributes of the DerivedKey have the following meanings:

   o  ID (OPTIONAL), the unique ID for this key

   o  Type (OPTIONAL), This attribute was included for conformance with
      xml encryption, it is an optional attribute identifying type
      information about the plaintext form of the encrypted content.
      Please see [XMLENC] section 3.1 Type for more details.

   The elements of the DerivedKey have the following meanings:

   o  <KeyDerivationMethod>: URI of the algorithms used to derive the
      key e.g.
      (http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5#pbkdf2)

   o  <ReferenceList (OPTIONAL)>: a list of IDs of the elements that
      have been encrypted by this key

   o  <CarriedKeyName (OPTIONAL)>: friendly name of the key

   When using the PKCS5 PBE algorithm
   (URI=http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5#pbes2)
   and related parameters, the DerivedKey element MUST be used within
   the EncryptionKey element of the KeyContainer in exactly the form as
   shown below:



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   <?xml version="1.0" encoding="UTF-8"?>
   <KeyContainer
     xmlns="urn:ietf:params:xml:ns:keyprov:container:1.0"
     xmlns:pkcs-5=
       "http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5v2-0#"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
     xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
     Version="1.0">
       <EncryptionKey>
         <DerivedKey Id="#Passphrase1">
           <CarriedKeyName>Passphrase1</CarriedKeyName>
           <KeyDerivationMethod
             Algorithm=
        "http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5#pbkdf2">
             <Parameters xsi:type="pkcs-5:PBKDF2ParameterType">
               <Salt>
                 <Specified>Df3dRAhjGh8=</Specified>
               </Salt>
               <IterationCount>2000</IterationCount>
               <KeyLength>16</KeyLength>
               <PRF/>
             </Parameters>
           </KeyDerivationMethod>
         </DerivedKey>
       </EncryptionKey>
   ....

6.2.  Protecting keys using asymmetric algorithms

   The following is the list of asymmetric key encryption algorithm and
   possible parameters used to protect the Secret Key data in the
   container.  Systems implementing PSKC MUST support the MANDATORY
   algorithms detailed below.  The encryption algorithm URI can be one
   of the following.

   o  http://www.w3.org/2001/04/xmlenc#rsa-1_5 - MANDATORY

   o  http://www.w3.org/2001/04/xmlenc#rsa-oaep-mgf1p - OPTIONAL

   For example:










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   <?xml version="1.0" encoding="UTF-8"?>

   <pskc:KeyContainer Version="1.0"
     xmlns:pskc="urn:ietf:params:xml:ns:keyprov:container:1.0"
     xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
     xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
       <pskc:EncryptionKey>
           <ds:X509Data>
               <ds:X509Certificate>miib</ds:X509Certificate>
           </ds:X509Data>
       </pskc:EncryptionKey>
       <pskc:Device>
           <pskc:DeviceId>
               <pskc:Manufacturer>ACME</pskc:Manufacturer>
               <pskc:SerialNo>0755225266</pskc:SerialNo>
           </pskc:DeviceId>
           <pskc:Key KeyAlgorithm=
            "http://www.ietf.org/keyprov/pskc#hotp"
            KeyId="0755225266">
               <pskc:Issuer>AnIssuer</pskc:Issuer>
               <pskc:Usage OTP="true">
                   <pskc:ResponseFormat Length="8"
                   Format="DECIMAL"/>
               </pskc:Usage>
               <pskc:Data Name="COUNTER">
                   <pskc:PlainValue>AprkuA==</pskc:PlainValue>
               </pskc:Data>
               <pskc:Data Name="SECRET">
                 <pskc:EncryptedValue Id="ED">
                   <xenc:EncryptionMethod
                     Algorithm=
                     "http://www.w3.org/2001/04/xmlenc#rsa_1_5"/>
                   <xenc:CipherData>
                     <xenc:CipherValue>rf4dx3rvEPO0vKtKL14NbeVu8nk=
                     </xenc:CipherValue>
                   </xenc:CipherData>
                 </pskc:EncryptedValue>
               </pskc:Data>
           </pskc:Key>
       </pskc:Device>
   </pskc:KeyContainer>

6.3.  Profile of Key Algorithm

   This section profiles the type(s) of algorithm of that can be used by
   the key(s) transported in the container.  The following algorithm
   URIs are among the default support list.




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   o  http://www.w3.org/2001/04/xmlenc#tripledes-cbc

   o  http://www.w3.org/2001/04/xmlenc#aes128-cbc

   o  http://www.w3.org/2001/04/xmlenc#aes192-cbc

   o  http://www.w3.org/2001/04/xmlenc#aes256-cbc

   o  http://www.ietf.org/keyprov/pskc#hotp

   o  http://www.ietf.org/keyprov/pskc#pin

6.3.1.  OTP Key Algorithm Identifiers

   OTP key algorithm URIs have not been defined in a commonly available
   standard specification.  This document defines the following URIs for
   the standard OTP algorithms defined in [HOTP].

6.3.1.1.  HOTP

   Standard document: RFC4226

   Identifier: http://www.ietf.org/keyprov/pskc#hotp

   Note that the actual URL will be finalized once a URL for this
   document is determined.

6.3.1.2.  Other OTP Algorithms

   An implementation should refer to vendor registered OTP key algorithm
   URIs for other existing OTP algorithms, for example, the RSA SecurID
   OTP algorithm as follows.

   o  http://www.rsa.com/rsalabs/otps/schemas/2005/09/
      otps-wst#SecurID-AES

6.3.2.  PIN key value compare algorithm identifier

   PIN key algorithm URIs have not been defined in a commonly available
   standard specification.  This document defines the following URIs for
   a straight value comaprison of the transported secret key data as
   when required to compare a PIN.

   Identifier: http://www.ietf.org/keyprov/pskc#pin

   Note that the actual URL will be finalized once a URL for this
   document is determined.




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7.  Reserved data attribute names

   The following key data attribute names have been reserved:

      SECRET: the shared secret key value in binary, base64 encoded

      COUNTER: the event counter for event based OTP algorithms. 8 bytes
      unsigned integer in big endian (i.e. network byte order) form
      base64 encoded

      TIME: the time for time based OTP algorithms. 8 bytes unsigned
      integer in big endian (i.e. network byte order) form base64
      encoded (Number of seconds since 1970)

      TIME_INTERVAL: the time interval value for time based OTP
      algorithms. 8 bytes unsigned integer in big endian (i.e. network
      byte order) form base64 encoded.

      TIME_DRIFT: the device clock drift value for time based OTP
      algorithms.  The value indicates number of seconds that the device
      clock may drift each day. 2 bytes unsigned integer in big endian
      (i.e. network byte order) form base64 encoded.





























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8.  Formal Syntax

   The following syntax specification uses the widely adopted XML schema
   format as defined by a W3C recommendation
   (http://www.w3.org/TR/xmlschema-0/).  It is a complete syntax
   definition in the XML Schema Definition format (XSD)

   All implementations of this standard must comply with the schema
   below.


<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
  xmlns:pskc="urn:ietf:params:xml:ns:keyprov:container:1.0"
  xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
  xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
  targetNamespace="urn:ietf:params:xml:ns:keyprov:container:1.0"
  elementFormDefault="qualified" attributeFormDefault="unqualified"
  version="1.0">
    <xs:import namespace="http://www.w3.org/2000/09/xmldsig#"
      schemaLocation=
      "http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/
      xmldsig-core-schema.xsd"/>
    <xs:import namespace="http://www.w3.org/2001/04/xmlenc#"
      schemaLocation="http://www.w3.org/TR/2002/
      REC-xmlenc-core-20021210/xenc-schema.xsd"/>

    <xs:complexType name="KeyContainerType">
    <xs:sequence>
        <xs:element name="EncryptionKey" type="ds:KeyInfoType"
          minOccurs="0"/>
        <xs:element name="MACAlgorithm" type="pskc:KeyAlgorithmType"
          minOccurs="0"/>
        <xs:element name="Device" type="pskc:DeviceType"
          maxOccurs="unbounded"/>
        <xs:element name="Signature" type="ds:SignatureType"
          minOccurs="0"/>
    </xs:sequence>
    <xs:attribute name="Version" type="pskc:VersionType"
      use="required"/>
    </xs:complexType>
    <xs:simpleType name="VersionType" final="restriction">
            <xs:restriction base="xs:string">
                    <xs:pattern value="\d{1,2}\.\d{1,3}"/>
            </xs:restriction>
    </xs:simpleType>
        <xs:complexType name="KeyPropertiesType">
                <xs:sequence>



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                        <xs:element name="Issuer"
                        type="xs:string" minOccurs="0"/>
                        <xs:element name="Usage"
                        type="pskc:UsageType" minOccurs="0"/>
                        <xs:element name="KeyProfileId"
                        type="xs:string" minOccurs="0"/>
                        <xs:element name="MasterKeyId"
                        type="xs:string" minOccurs="0"/>
                        <xs:element name="Data" type="pskc:DataType"
                        minOccurs="0" maxOccurs="unbounded"/>
                        <xs:element name="PINPolicy"
                        type="pskc:PINPolicyType" minOccurs="0"/>
                        <xs:element name="ExpiryDate"
                        type="xs:dateTime" minOccurs="0"/>
                        <xs:element name="StartDate"
                        type="xs:dateTime" minOccurs="0"/>
                </xs:sequence>
                <xs:attribute name="KeyPropertiesId"
                type="xs:string" use="required"/>
                <xs:attribute name="KeyAlgorithm"
                type="pskc:KeyAlgorithmType"
                use="optional"/>
        </xs:complexType>
    <xs:complexType name="KeyType">
        <xs:sequence>
            <xs:element name="Issuer"
            type="xs:string" minOccurs="0"/>
            <xs:element name="Usage"
            type="pskc:UsageType"/>
                        <xs:element name="KeyProfileId"
                        type="xs:string" minOccurs="0"/>
                        <xs:element name="MasterKeyId"
                        type="xs:string" minOccurs="0"/>
            <xs:element name="FriendlyName"
            type="xs:string" minOccurs="0"/>
            <xs:element name="Data" type="pskc:DataType"
            minOccurs="0" maxOccurs="unbounded"/>
            <xs:element name="PINPolicy"
            type="pskc:PINPolicyType" minOccurs="0"/>
            <xs:element name="ExpiryDate"
            type="xs:dateTime" minOccurs="0"/>
            <xs:element name="StartDate"
            type="xs:dateTime" minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="KeyId"
        type="xs:string" use="required"/>
        <xs:attribute name="KeyAlgorithm"
        type="pskc:KeyAlgorithmType"



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          use="required"/>
    </xs:complexType>
    <xs:complexType name="DerivedKeyType">
        <xs:sequence>
            <xs:element name="KeyDerivationMethod"
              type="pskc:KeyDerivationMethodType" minOccurs="0"/>
            <xs:element ref="xenc:ReferenceList" minOccurs="0"/>
            <xs:element name="CarriedKeyName" type="xs:string"
              minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="Id" type="xs:ID" use="optional"/>
        <xs:attribute name="Type" type="xs:anyURI" use="optional"/>
    </xs:complexType>
    <xs:complexType name="KeyDerivationMethodType">
        <xs:sequence>
            <xs:any namespace="##other" minOccurs="0"
            maxOccurs="unbounded"/>
        </xs:sequence>
        <xs:attribute name="Algorithm" type="xs:anyURI"
        use="required"/>
    </xs:complexType>
    <xs:complexType name="PINPolicyType">
        <xs:sequence>
            <xs:element name="PINUsageMode"
              type="pskc:PINUsageModeType"/>
            <xs:element name="WrongPINtry" type="xs:unsignedInt"
              minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="PINKeyId" type="xs:string"
          use="required"/>
    </xs:complexType>
    <xs:complexType name="PINUsageModeType">
            <xs:choice maxOccurs="unbounded">
                    <xs:element name="Local"/>
                    <xs:element name="Prepend"/>
                    <xs:element name="Embed"/>
            </xs:choice>
    </xs:complexType>
    <xs:complexType name="DeviceIdType">
        <xs:sequence>
        <xs:element name="Manufacturer" type="xs:string"/>
        <xs:element name="SerialNo" type="xs:string"/>
        <xs:element name="Model" type="xs:string"
        minOccurs="0"/>
        <xs:element name="IssueNo" type="xs:string"
        minOccurs="0"/>
        <xs:element name="ExpiryDate" type="xs:dateTime"
        minOccurs="0"/>



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        <xs:element name="StartDate" type="xs:dateTime"
        minOccurs="0"/>
        </xs:sequence>
    </xs:complexType>
    <xs:complexType name="DeviceType">
      <xs:sequence>
        <xs:element name="DeviceId" type="pskc:DeviceIdType"
          minOccurs="0"/>
        <xs:element name="Key" type="pskc:KeyType"
          maxOccurs="unbounded"/>
        <xs:element name="UserId" type="xs:string"
        minOccurs="0"/>
      </xs:sequence>
    </xs:complexType>
    <xs:complexType name="UsageType">
        <xs:sequence>
            <xs:element name="ChallengeFormat" minOccurs="0">
                <xs:complexType>
                    <xs:attribute name="Format"
                      type="pskc:ValueFormatType" use="required"/>
                    <xs:attribute name="Min" type="xs:unsignedInt"
                      use="required"/>
                    <xs:attribute name="Max" type="xs:unsignedInt"
                      use="required"/>
                    <xs:attribute name="CheckDigits" type="xs:boolean"
                      default="false"/>
                </xs:complexType>
            </xs:element>
            <xs:element name="ResponseFormat">
                <xs:complexType>
                    <xs:attribute name="Format"
                      type="pskc:ValueFormatType" use="required"/>
                    <xs:attribute name="Length" type="xs:unsignedInt"
                      use="required"/>
                    <xs:attribute name="CheckDigits" type="xs:boolean"
                      default="false"/>
                </xs:complexType>
            </xs:element>
            </xs:sequence>
            <xs:attribute name="OTP" type="xs:boolean" default="false"/>
            <xs:attribute name="CR" type="xs:boolean" default="false"/>
            <xs:attribute name="Integrity" type="xs:boolean"
              default="false"/>
            <xs:attribute name="Encrypt" type="xs:boolean"
              default="false"/>
            <xs:attribute name="Unlock" type="xs:boolean"
              default="false"/>
    </xs:complexType>



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    <xs:complexType name="DataType">
        <xs:sequence>
            <xs:choice>
                <xs:element name="PlainValue" type="xs:base64Binary"/>
                <xs:element name="EncryptedValue"
                  type="xenc:EncryptedDataType"/>
            </xs:choice>
            <xs:element name="ValueMAC" type="xs:base64Binary"
              minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="Name" type="xs:string" use="required"/>
    </xs:complexType>
    <xs:simpleType name="KeyAlgorithmType">
        <xs:restriction base="xs:anyURI"/>
    </xs:simpleType>
    <xs:simpleType name="ValueFormatType">
        <xs:restriction base="xs:string">
            <xs:enumeration value="DECIMAL"/>
            <xs:enumeration value="HEXADECIMAL"/>
            <xs:enumeration value="ALPHANUMERIC"/>
            <xs:enumeration value="BASE64"/>
            <xs:enumeration value="BINARY"/>
        </xs:restriction>
    </xs:simpleType>
    <xs:element name="KeyContainer" type="pskc:KeyContainerType"/>
</xs:schema>

























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9.  IANA Considerations

9.1.  Content-type registration for 'application/pskc+xml'

   This specification requests the registration of a new MIME type
   according to the procedures of RFC 4288 [RFC4288] and guidelines in
   RFC 3023 [RFC3023].

   MIME media type name:  application

   MIME subtype name:  pskc+xml

   Mandatory parameters:  none

   Optional parameters:  charset

      Indicates the character encoding of enclosed XML.

   Encoding considerations:  Uses XML, which can employ 8-bit
      characters, depending on the character encoding used.  See RFC
      3023 [RFC3023], Section 3.2.

   Security considerations:  This content type is designed to carry PSKC
      protocol payloads.

   Interoperability considerations:  None

   Published specification:  RFCXXXX [NOTE TO IANA/RFC-EDITOR: Please
      replace XXXX with the RFC number of this specification.]

   Applications which use this media type:  This MIME type is being used
      as a symmetric key container format for transport and provisioning
      of symmetric keys (One Time Password (OTP) shared secrets or
      symmetric cryptographic keys) to different types of strong
      authentication devices.  As such, it is used for key provisioning
      systems.

   Additional information:

      Magic Number:  None

      File Extension:  .pskcxml

      Macintosh file type code:  'TEXT'







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   Personal and email address for further information:  Philip Hoyer,
      Philip.Hoyer@actividentity.com

   Intended usage:  LIMITED USE

   Author:  This specification is a work item of the IETF KEYPROV
      working group, with mailing list address <keyprov@ietf.org>.

   Change controller:  The IESG <iesg@ietf.org>

9.2.  XML Schema Registration

   This section registers an XML schema as per the guidelines in
   [RFC3688].

   URI:  urn:ietf:params:xml:ns:keyprov:container:1.0

   Registrant Contact:  IETF KEYPROV Working Group, Philip Hoyer
      (Philip.Hoyer@actividentity.com).

   XML Schema:  The XML schema to be registered is contained in
      Section 8.  Its first line is

   <?xml version="1.0" encoding="UTF-8"?>

      and its last line is

   </xs:schema>

9.3.  URN Sub-Namespace Registration for
      urn:ietf:params:xml:ns:keyprov:container:1.0

   This section registers a new XML namespace,
   "urn:ietf:params:xml:ns:keyprov:container:1.0", per the guidelines in
   [RFC3688].

   URI:  urn:ietf:params:xml:ns:keyprov:container:1.0

   Registrant Contact:  IETF KEYPROV Working Group, Philip Hoyer
      (Philip.Hoyer@actividentity.com).

   XML:









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   BEGIN
   <?xml version="1.0"?>
   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
     "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
   <html xmlns="http://www.w3.org/1999/xhtml">
   <head>
     <meta http-equiv="content-type"
           content="text/html;charset=iso-8859-1"/>
     <title>PSKC Namespace</title>
   </head>
   <body>
     <h1>Namespace for PSKC</h1>
     <h2>urn:ietf:params:xml:ns:keyprov:container:1.0</h2>
   <p>See <a href="[URL of published RFC]">RFCXXXX
       [NOTE TO IANA/RFC-EDITOR:
        Please replace XXXX with the RFC number of this
       specification.]</a>.</p>
   </body>
   </html>
   END

9.4.  Symmetric Key Algorithm Identifier Registry

   This specification requests the creation of a new IANA registry for
   symmetric key cryptographic algorithm identifiers in accordance with
   the principles set out in RFC 2434 [RFC2434]as follows:

9.4.1.  Applicability

   The use of URIs as algorithm identifiers provides an effectively
   unlimited namespace.  While this eliminates the possibility of
   namespace exhaustion it creates a new concern, that divergent
   identifiers will be employed for the same purpose in different
   contexts.

   The key algorithm registry is intended to provide a means of
   specifying the canonical identifier to be used for a given algorithm.
   If an algorithm has an identifier specified in the registry a
   application that is conformant to a protocol specification that
   specifies use of that registry to define identifiers SHOULD always
   use that particular form of the identifier when originating data.  A
   conformant application MAY accept other identifiers in data that is
   received.

   For the sake of expediency, the initial registry only defines
   algorithm classes for symmetric algorithms plus cryptographic message
   digest functions (one-way hash).  While the same principles may be
   extended to asymmetric algorithms, doing so would require much



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   greater consideration of issues such as key length and treatment of
   parameters, particularly where eliptic curve cryptography algorithms
   are concerned.

   As part of this registry the IANA will maintain the following
   information:

   Common Name  The name by which the algorithm is generally referred.

   Class  The type of algorithm, encryption, Message Authentication Code
      (MAC), One Time Pawword (OTP), Digest, etc.

   Cannonical URI  The cannonical URI to be used to identify the
      algorithm.

   Algorithm Definition  A reference to the document in which the
      algorithm described by the identifier is defined.

   Identifier Definition  A reference to the document in which the use
      of the identifier to refer to the algorithm is described.  This
      would ideally be the document in which the algorithm is defined.

      In the case where the registrant does not request a particular
      URI, the IANA will assign it a Uniform Resource Name (URN) that
      follows RFC 3553 [RFC3553].

   Note that where a single algorithm has different forms distinguished
   by paremeters such as key length, the algorithm class and each
   combination of algorithm parameters may be considered a distinct
   algorithm for the purpose of assigning identifiers.

9.4.2.  Registerable Algorithms

9.4.2.1.  Assigned URIs

   If the registrant wishes to have a URI assigned, then a URN of the
   form

   urn:ietf:params:xml:<class>:<id>

   will be assigned where <class> is the type of the algorithm being
   identified (see below). <id> is a unique id specified by the party
   making the request and will normally be either the common name of the
   algorithm or an abbreviation thereof.

   NOTE: in order for a URN of this type to be assigned, the item being
   registered MUST have been through the IETF consensus process.
   Basically, this means that it must be documented in a RFC.



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   NOTE: Expert Review is sufficient in cases where the request does not
   require a URN assignment inthe IETF namespace.  IETF consensus is not
   required.

9.4.2.2.  Assigned Classes

   Each algorithm MUST belong to an assigned algorithm class.  In the
   case that additional classes are required these are to be specified
   by IETF Consensus action.

   The initial assigned classes are:

   Digest  A cryptographic Digest algorithm.

   MAC  A Message Authentication Code algorithm.

   Symmetric  A symmetric encryption algorithm.

   OTP  A one time password (OTP) algorithm.

9.4.3.  Registration Procedures

9.4.3.1.  Review

   Algorithm identifier registrations are to be subject to Expert Review
   as per RFC 2434 [RFC2434].

   The need for supporting documentation for the registration depends on
   the nature of the request.  In the case of a cryptographic algorithm
   that is being described for publication as an RFC, the request for a
   URI allocation would normally appear within the RFC itself.  In the
   case of a cryptographic algorithm that is fully and comprehensively
   defined in another form, it would not be necessary to duplicate the
   information for the sake of issuing the information in the RFC
   series.  In other cases an RFC may be required in order to ensure
   that certain algorithm parameters are sufficiently and unambiguously
   defined.

   The scope of such expert review is to be strictly limited to
   identifying possible ambiguity and/or duplication of existing
   identifiers.  The expert review MUST NOT consider the cryptographic
   properties, intellectual property considerations or any other factor
   not related to the use of the identifier.

   In reviewing a request, the expert should consider whether other URI
   identifiers are already defined for a given algorithm.  In such cases
   it is the duty of the expert to bring the potential duplication to
   the notice of the proposers of the registration and the Security Area



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   Directors.  If the proposers are not willing to accept registration
   of the existing identifier the IETF Consensus policy is to apply.

   In reviewing a request, the expert should consider whether the
   algorithm is sufficiently defined to allow successful interoperation.
   In particular the expert should consider whether issues such as key
   sizes and byte order are sufficiently defined to allow for
   interoperation.

   While the defintion requirement MAY be satisifed by a comprehensive
   specification of the algorithm, disclosure of the algorithm is not
   mandatory.

9.4.3.2.  Canonical URI

   Until the IANA requests or implements an automated process for the
   registration of these elements, any specifications must make that
   request part of the IANA considerations section of their respective
   documents.  That request must be in the form of the following
   template:

   Common Name  The name by which the algorithm is generally referred.

   Class  The type of algorithm, encryption, Message Authentication Code
      (MAC), One Time Pawword (OTP), Digest, etc.  As specified by a
      defined algorithm class.

   URI  The cannonical URI to be used to identify the algorithm.

   Algorithm Definition  A reference to the document in which the
      algorithm described by the identifier is defined.

   Identifier Definition  A reference to the document in which the use
      of the identifier to refer to the algorithm is described.  This
      would ideally be the document in which the algorithm is defined.

   Registrant Contact  A reference to the document in which the use of
      the identifier to refer to the algorithm is described.  This would
      ideally be the document in which the algorithm is defined.

9.4.3.3.  Alias URI

   In the case that multiple identifiers have been assigned to the same
   identifiers, additional identifiers MAY be registered as aliases.  An
   entry for an alias contains all the entries for a canonical URI with
   the addition of a reference to the canonical URI to be used:





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   Alias for URI  The cannonical URI that identifies the algorithm.  The
      URI referenced MUST be a canonical URI.

   In the case of dispute as to which URI is to be considered canonical
   the matter is to be settled by IESG action.

9.4.4.  Initial Values

   The following initial values are defined.  Note that these values are
   limited to identifiers that are required by KEYPROV but not specified
   elsewhere:

9.4.4.1.  HOTP

   Common Name:  HOTP

   Class:  OTP

   URI:  http://www.ietf.org/keyprov/pskc#hotp

   Algorithm Definition:  http://www.ietf.org/rfc/rfc4226.txt

   Identifier Definition  (this RFC)

   Registrant Contact:  IESG

9.4.4.2.  HOTP-HMAC-SHA-1

   Common Name:  HOTP-HMAC-SHA-1

   Class:  OTP

   URI:  http://www.ietf.org/rfc/rfc4226.txt#HOTP-HMAC-SHA-1

   Algorithm Definition:  http://www.ietf.org/rfc/rfc4226.txt

   Identifier Definition  (this RFC)

   Registrant Contact:  IESG

9.4.4.3.  KEYPROV-PIN

   Common Name:  KEYPROV-PIN

   Class:  Symmetric static credential comparison






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   URI:  http://www.ietf.org/keyprov/pskc#pin

   Algorithm Definition:  (this document)

   Identifier Definition  (this document)

   Registrant Contact:  IESG

9.4.4.4.  SecurID-AES

   Common Name:  SecurID-AES

   Class:  OTP

   URI:  http://www.rsasecurity.com/rsalabs/otps/schemas/2005/09/
      otps-wst#SecurID-AES

   Algorithm Definition:  http://www.rsa.com/rsalabs/node.asp?id=2821

   Identifier Definition  http://www.rsa.com/rsalabs/node.asp?id=2821

   Registrant Contact:  Andrea Doherty, RSA the Security Division of
      EMC, <andrea.doherty@rsa.com>

9.4.4.5.  SecurID-ALGOR

   Common Name:  SecurID-ALGOR

   Class:  OTP

   URI:  http://www.rsasecurity.com/rsalabs/otps/schemas/2005/09/
      otps-wst#SecurID-ALGOR

   Algorithm Definition:  http://www.rsa.com/rsalabs/node.asp?id=2821

   Identifier Definition  http://www.rsa.com/rsalabs/node.asp?id=2821

   Registrant Contact:  Andrea Doherty, RSA the Security Division of
      EMC, <andrea.doherty@rsa.com>

9.4.4.6.  ActivIdentity-3DES

   Common Name:  ActivIdentity-3DES

   Class:  OTP






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   URI:  http://www.actividentity.com/2008/04/algorithms/
      algorithms#ActivIdentity-3DES

   Algorithm Definition:  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-3DES

   Identifier Definition  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-3DES

   Registrant Contact:  Philip Hoyer, ActivIdentity Inc,
      <philip.hoyer@actividentity.com>

9.4.4.7.  ActivIdentity-AES

   Common Name:  ActivIdentity-AES

   Class:  OTP

   URI:  http://www.actividentity.com/2008/04/algorithms/
      algorithms#ActivIdentity-AES

   Algorithm Definition:  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-AES

   Identifier Definition  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-AES

   Registrant Contact:  Philip Hoyer, ActivIdentity Inc,
      <philip.hoyer@actividentity.com>

9.4.4.8.  ActivIdentity-DES

   Common Name:  ActivIdentity-DES

   Class:  OTP

   URI:  http://www.actividentity.com/2008/04/algorithms/
      algorithms#ActivIdentity-DES

   Algorithm Definition:  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-DES

   Identifier Definition  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-DES







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   Registrant Contact:  Philip Hoyer, ActivIdentity Inc,
      <philip.hoyer@actividentity.com>

9.4.4.9.  ActivIdentity-EVENT

   Common Name:  ActivIdentity-EVENT

   Class:  OTP

   URI:  http://www.actividentity.com/2008/04/algorithms/
      algorithms#ActivIdentity-EVENT

   Algorithm Definition:  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-EVENT

   Identifier Definition  http://www.actividentity.com/2008/04/
      algorithms/algorithms#ActivIdentity-EVENT

   Registrant Contact:  Philip Hoyer, ActivIdentity Inc,
      <philip.hoyer@actividentity.com>

9.5.  XML Data Tag Identifier Registry

   This specification requests the creation of a new IANA registry for
   XML Data Tag identifiers in accordance with the principles set out in
   RFC 2434 [RFC2434]as follows:

   [More explanation of why an escape to tag value lists is desirable
   when inserting unstructured data into an XML schema]

9.5.1.  Applicability

   As part of this registry the IANA will maintain the following
   information:

   Common Name  Common name for by which the tag is referred to

   Cannonical URI  The cannonical URI to be employed when citing the
      tag.

   Data Type  The data type of the data that is bound to the tag.

    Definition  A reference to the document in which the data tag
      defined by the identifier is defined.

   In the case where the registrant does not request a particular URI,
   the IANA will assign it a Uniform Resource Name (URN) that follows
   RFC 3553 [RFC3553].



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9.5.2.  Registerable Data Tags

9.5.2.1.  Assigned URIs

   If the registrant wishes to have a URI assigned, then a URN of the
   form

   urn:ietf:params:xml:datatag:<tag>

   will be assigned where <tag> is a unique id specified by the party
   making the request and will normally be either the common name of the
   tag or an abbreviation thereof.

   NOTE: in order for a URN of this type to be assigned, the item being
   registered MUST have been through the IETF consensus process.
   Basically, this means that it must be documented in a RFC.

   NOTE: Expert Review is sufficient in cases where the request does not
   require a URN assignment inthe IETF namespace.  IETF consensus is not
   required.

9.5.3.  Registration Procedures

9.5.3.1.  Review

   Data tag registrations are to be subject to Expert Review as per RFC
   2434 [RFC2434].

9.5.3.2.  Data Tag Entry

   Until the IANA requests or implements an automated process for the
   registration of these elements, any specifications must make that
   request part of the IANA considerations section of their respective
   documents.  That request must be in the form of the following
   template:

   Common Name  Common name for by which the tag is referred to

   Cannonical URI  The cannonical URI to be employed when citing the
      tag.

   Data Type  The data type of the data that is bound to the tag.

    Definition  A reference to the document in which the data tag
      defined by the identifier is defined.






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9.5.4.  Initial Values

   The following initial values are defined.  Note that these values are
   limited to identifiers that are required by KEYPROV but not specified
   elsewhere:

9.5.4.1.  Secret

   Common Name  Secret

   Cannonical URI  urn:ietf:params:xml:datatag:secret

   Data Type  binary, base64 encoded

   Defined in  (this document)

9.5.4.2.  Counter

   Common Name  Counter

   Cannonical URI  urn:ietf:params:xml:datatag:counter

   Data Type  8 bytes unsigned integer in big endian (i.e. network byte
      order) form base64 encoded

   Defined in  (this document)

9.5.4.3.  Time

   Common Name  Time

   Cannonical URI  urn:ietf:params:xml:datatag:time

   Data Type  8 bytes unsigned integer in big endian (i.e. network byte
      order) form base64 encoded (Number of seconds since 1970)

   Defined in  (this document)

9.5.4.4.  Time Interval

   Common Name  Time Interval

   Cannonical URI  urn:ietf:params:xml:datatag:time_interval

   Data Type  8 bytes unsigned integer in big endian (i.e. network byte
      order) form base64 encoded.





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   Defined in  (this document)

9.5.4.5.  Time Drift

   Common Name  urn:ietf:params:xml:datatag:time_drift

   Cannonical URI  Time Drift

   Data Type  2 bytes unsigned integer in big endian (i.e. network byte
      order) form base64 encoded.

   Defined in  (this document)







































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10.  Security Considerations

   The portable key container carries sensitive information (e.g.,
   cryptographic keys) and may be transported across the boundaries of
   one secure perimeter to another.  For example, a container residing
   within the secure perimeter of a back-end provisioning server in a
   secure room may be transported across the internet to an end-user
   device attached to a personal computer.  This means that special care
   must be taken to ensure the confidentiality, integrity, and
   authenticity of the information contained within.

10.1.  Payload confidentiality

   By design, the container allows two main approaches to guaranteeing
   the confidentiality of the information it contains while transported.

   First, the container key data payload may be encrypted.

   In this case no transport layer security is required.  However,
   standard security best practices apply when selecting the strength of
   the cryptographic algorithm for payload encryption.  Symmetric
   cryptographic cipher should be used - the longer the cryptographic
   key, the stronger the protection.  At the time of this writing both
   3DES and AES are mandatory algorithms but 3DES may be dropped in the
   relatively near future.  Applications concerned with algorithm
   longevity are advised to use AES-256-CBC.  In cases where the
   exchange of encryption keys between the sender and the receiver is
   not possible, asymmetric encryption of the secret key payload may be
   employed.  Similarly to symmetric key cryptography, the stronger the
   asymmetric key, the more secure the protection is.

   If the payload is encrypted with a method that uses one of the
   password-based encryption methods provided above, the payload may be
   subjected to password dictionary attacks to break the encryption
   password and recover the information.  Standard security best
   practices for selection of strong encryption passwords apply
   [Schneier].

   Practical implementations should use PBESalt and PBEIterationCount
   when PBE encryption is used.  Different PBESalt value per key
   container should be used for best protection.

   The second approach to protecting the confidentiality of the payload
   is based on using transport layer security.  The secure channel
   established between the source secure perimeter (the provisioning
   server from the example above) and the target perimeter (the device
   attached to the end-user computer) utilizes encryption to transport
   the messages that travel across.  No payload encryption is required



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   in this mode.  Secure channels that encrypt and digest each message
   provide an extra measure of security, especially when the signature
   of the payload does not encompass the entire payload.

   Because of the fact that the plain text payload is protected only by
   the transport layer security, practical implementation must ensure
   protection against man-in-the-middle attacks [Schneier].  Validating
   the secure channel end-points is critically important for eliminating
   intruders that may compromise the confidentiality of the payload.

10.2.  Payload integrity

   The portable symmetric key container provides a mean to guarantee the
   integrity of the information it contains through digital signatures.
   For best security practices, the digital signature of the container
   should encompass the entire payload.  This provides assurances for
   the integrity of all attributes.  It also allows verification of the
   integrity of a given payload even after the container is delivered
   through the communication channel to the target perimeter and channel
   message integrity check is no longer possible.

10.3.  Payload authenticity

   The digital signature of the payload is the primary way of showing
   its authenticity.  The recipient of the container may use the public
   key associated with the signature to assert the authenticity of the
   sender by tracing it back to a preloaded public key or certificate.
   Note that the digital signature of the payload can be checked even
   after the container has been delivered through the secure channel of
   communication.

   A weaker payload authenticity guarantee may be provided by the
   transport layer if it is configured to digest each message it
   transports.  However, no authenticity verification is possible once
   the container is delivered at the recipient end.  This approach may
   be useful in cases where the digital signature of the container does
   not encompass the entire payload.














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11.  Acknowledgements

   The authors of this draft would like to thank the following people
   for their contributions and support to make this a better
   specification: Apostol Vassilev, Shuh Chang, Jon Martinson, Siddhart
   Bajaj, Stu Veath, Kevin Lewis, Philip Hallam-Baker, Hannes
   Tschofenig, Andrea Doherty, Magnus Nystrom, Tim Moses, and Anders
   Rundgren.











































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12.  Appendix A - Example Symmetric Key Containers

   All examples are syntactically correct and compatible with the XML
   schema in section 7.

12.1.  Symmetric Key Container with a single Non-Encrypted HOTP Secret
       Key


   <?xml version="1.0" encoding="UTF-8"?>
   <KeyContainer Version="1.0"
     xmlns="urn:ietf:params:xml:ns:keyprov:container:1.0">
       <Device>
           <DeviceId>
               <Manufacturer>ACME</Manufacturer>
               <SerialNo>0755225266</SerialNo>
           </DeviceId>
           <Key KeyAlgorithm="http://www.ietf.org/keyprov/pskc#hotp"
             KeyId="0755225266">
               <Issuer>AnIssuer</Issuer>
               <Usage OTP="true">
                   <ResponseFormat Length="6" Format="DECIMAL"/>
               </Usage>
               <Data Name="COUNTER">
                   <PlainValue>AprkuA==</PlainValue>
               </Data>
               <Data Name="SECRET">
                   <PlainValue>/4h3rOTeBegJwGpmTTq4F+RlNR0=</PlainValue>
               </Data>
               <ExpiryDate>2012-12-31T00:00:00</ExpiryDate>
           </Key>
       </Device>
   </KeyContainer>


12.2.  Symmetric Key Container with a single PIN protected Non-Encrypted
       HOTP Secret Key














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   <?xml version="1.0" encoding="UTF-8"?>
   <KeyContainer Version="1.0"
     xmlns="urn:ietf:params:xml:ns:keyprov:container:1.0">
       <Device>
           <DeviceId>
               <Manufacturer>ACME</Manufacturer>
               <SerialNo>0755225266</SerialNo>
           </DeviceId>
           <Key KeyAlgorithm="http://www.ietf.org/keyprov/pskc#hotp"
             KeyId="0755225266">
               <Issuer>AnIssuer</Issuer>
               <Usage OTP="true">
                   <ResponseFormat Length="6" Format="DECIMAL"/>
               </Usage>
               <Data Name="COUNTER">
                   <PlainValue>AprkuA==</PlainValue>
               </Data>
               <Data Name="SECRET">
                   <PlainValue>/4h3rOTeBegJwGpmTTq4F+RlNR0=</PlainValue>
               </Data>
               <PINPolicy PINKeyId="07552252661">
                   <PINUsageMode>
                       <Local/>
                   </PINUsageMode>
               </PINPolicy>
           </Key>
           <Key KeyId="07552252661"
             KeyAlgorithm="http://www.ietf.org/keyprov/pskc#pin">
               <Usage>
                   <ResponseFormat Length="4" Format="DECIMAL"/>
               </Usage>
               <Data Name="SECRET">
                   <PlainValue>MTIzNA==</PlainValue>
               </Data>
           </Key>
       </Device>
   </KeyContainer>

12.3.  Symmetric Key Container with a single AES-256-CBC Encrypted HOTP
       Secret Key











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<?xml version="1.0" encoding="UTF-8"?>
<KeyContainer Version="1.0"
  xmlns="urn:ietf:params:xml:ns:keyprov:container:1.0"
  xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
  xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
    <EncryptionKey>
        <ds:KeyName>PRE_SHARED_KEY</ds:KeyName>
    </EncryptionKey>
    <MACAlgorithm>http://www.w3.org/2000/09/xmldsig#hmac-sha1
    </MACAlgorithm>
    <Device>
        <DeviceId>
            <Manufacturer>ACME</Manufacturer>
            <SerialNo>0755225266</SerialNo>
        </DeviceId>
        <Key KeyAlgorithm="http://www.ietf.org/keyprov/pskc#hotp"
          KeyId="0755225266">
            <Issuer>AnIssuer</Issuer>
            <Usage OTP="true">
                <ResponseFormat Length="8" Format="DECIMAL"/>
            </Usage>
            <Data Name="COUNTER">
                <PlainValue>AprkuA==</PlainValue>
            </Data>
            <Data Name="SECRET">
                <EncryptedValue>
                    <xenc:EncryptionMethod
               Algorithm="http://www.w3.org/2001/04/xmlenc#aes256-cbc"/>
                    <xenc:CipherData>
                      <xenc:CipherValue>
                        kyzrWTJuhJKQHhZtf2CWbKC5H3LdfAPvKzHHQ8SdxyE=
                      </xenc:CipherValue>
                    </xenc:CipherData>
                </EncryptedValue>
                <ValueMAC>cwJI898rRpGBytTqCAsegaQqPZA=</ValueMAC>
            </Data>
        </Key>
    </Device>
</KeyContainer>

12.4.  Symmetric Key Container with signature and a single Password-
       based Encrypted HOTP Secret Key


 <?xml version="1.0" encoding="UTF-8"?>
 <pskc:KeyContainer
   xmlns:pskc="urn:ietf:params:xml:ns:keyprov:container:1.0"
   xmlns:pkcs-5=



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     "http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5v2-0#"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
   xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"
   Version="1.0">
     <pskc:EncryptionKey>
       <pskc:DerivedKey Id="#Passphrase1">
         <pskc:CarriedKeyName>Passphrase1</pskc:CarriedKeyName>
         <pskc:KeyDerivationMethod
           Algorithm=
      "http://www.rsasecurity.com/rsalabs/pkcs/schemas/pkcs-5#pbkdf2">
           <pkcs-5:Parameters xsi:type="pkcs-5:PBKDF2ParameterType">
             <Salt>
               <Specified>Df3dRAhjGh8=</Specified>
             </Salt>
             <IterationCount>2000</IterationCount>
             <KeyLength>16</KeyLength>
             <PRF/>
           </pkcs-5:Parameters>
         </pskc:KeyDerivationMethod>
         <xenc:ReferenceList>
           <xenc:DataReference URI="#ED"/>
         </xenc:ReferenceList>
       </pskc:DerivedKey>
     </pskc:EncryptionKey>
   <pskc:Device>
     <pskc:DeviceId>
       <pskc:Manufacturer>ACME</pskc:Manufacturer>
       <pskc:SerialNo>0755225266</pskc:SerialNo>
     </pskc:DeviceId>
         <pskc:Key KeyAlgorithm="http://www.ietf.org/keyprov/pskc#hotp"
           KeyId="0755225266">
             <pskc:Issuer>AnIssuer</pskc:Issuer>
             <pskc:Usage OTP="true">
                 <pskc:ResponseFormat Length="6" Format="DECIMAL"/>
             </pskc:Usage>
             <pskc:Data Name="COUNTER">
                 <pskc:PlainValue>AprkuA==</pskc:PlainValue>
             </pskc:Data>
             <pskc:Data Name="SECRET">
                 <pskc:EncryptedValue Id="ED">
                   <xenc:EncryptionMethod Algorithm=
                   "http://www.w3.org/2001/04/xmlenc#kw-aes128"/>
                   <xenc:CipherData>
                     <xenc:CipherValue>rf4dx3rvEPO0vKtKL14NbeVu8nk=
                     </xenc:CipherValue>
                   </xenc:CipherData>
                 </pskc:EncryptedValue>



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             </pskc:Data>
         </pskc:Key>
   </pskc:Device>
   <pskc:Signature>
     <ds:SignedInfo>
       <ds:CanonicalizationMethod
         Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
       <ds:SignatureMethod
         Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/>
       <ds:Reference URI="">
         <ds:DigestMethod Algorithm=
           "http://www.w3.org/2000/09/xmldsig#sha1"/>
         <ds:DigestValue>j6lwx3rvEPO0vKtMup4NbeVu8nk=</ds:DigestValue>
       </ds:Reference>
     </ds:SignedInfo>
     <ds:SignatureValue>j6lwx3rvEPO0vKtMup4NbeVu8nk=</ds:SignatureValue>
     <ds:KeyInfo>
       <ds:X509Data>
         <ds:X509IssuerSerial>
           <ds:X509IssuerName>CN=KeyProvisioning'R'Us.com,C=US
           </ds:X509IssuerName>
           <ds:X509SerialNumber>12345678</ds:X509SerialNumber>
         </ds:X509IssuerSerial>
       </ds:X509Data>
     </ds:KeyInfo>
   </pskc:Signature>
 </pskc:KeyContainer>


12.5.  Symmetric Key Container with a single RSA 1.5 Encrypted HOTP
       Secret Key




















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<?xml version="1.0" encoding="UTF-8"?>
<pskc:KeyContainer Version="1.0"
  xmlns:pskc="urn:ietf:params:xml:ns:keyprov:container:1.0"
  xmlns:ds="http://www.w3.org/2000/09/xmldsig#"
  xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
    <pskc:EncryptionKey>
        <ds:X509Data>
            <ds:X509Certificate>miib</ds:X509Certificate>
        </ds:X509Data>
    </pskc:EncryptionKey>
    <pskc:Device>
        <pskc:DeviceId>
            <pskc:Manufacturer>ACME</pskc:Manufacturer>
            <pskc:SerialNo>0755225266</pskc:SerialNo>
        </pskc:DeviceId>
        <pskc:Key KeyAlgorithm="http://www.ietf.org/keyprov/pskc#hotp"
                  KeyId="0755225266">
            <pskc:Issuer>AnIssuer</pskc:Issuer>
            <pskc:Usage OTP="true">
                <pskc:ResponseFormat Length="8" Format="DECIMAL"/>
            </pskc:Usage>
            <pskc:Data Name="COUNTER">
                <pskc:PlainValue>AprkuA==</pskc:PlainValue>
            </pskc:Data>
            <pskc:Data Name="SECRET">
              <pskc:EncryptedValue Id="ED">
                <xenc:EncryptionMethod
                  Algorithm="http://www.w3.org/2001/04/xmlenc#rsa_1_5"/>
                <xenc:CipherData>
                  <xenc:CipherValue>rf4dx3rvEPO0vKtKL14NbeVu8nk=
                  </xenc:CipherValue>
                </xenc:CipherData>
              </pskc:EncryptedValue>
            </pskc:Data>
        </pskc:Key>
    </pskc:Device>
</pskc:KeyContainer>














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13.  References

13.1.  Normative References

   [PKCS1]    Kaliski, B., "RFC 2437: PKCS #1: RSA Cryptography
              Specifications Version 2.0.",
              URL: http://www.ietf.org/rfc/rfc2437.txt, Version: 2.0,
              October 1998.

   [PKCS5]    RSA Laboratories, "PKCS #5: Password-Based Cryptography
              Standard", Version 2.0,
              URL: http://www.rsasecurity.com/rsalabs/pkcs/, March 1999.

   [RFC2119]  "Key words for use in RFCs to Indicate Requirement
              Levels", BCP 14, RFC 2119, March 1997,
              <http://www.ietf.org/rfc/rfc2119.txt>.

   [RFC2434]  Narten, T., "Guidelines for Writing an IANA Considerations
              Section in RFCs", RFC 2434, October 1998.

   [RFC3023]  Murata, M., St. Laurent, S., and D. Kohn, "XML Media
              Types", RFC 3023, January 2001.

   [RFC3553]  Mealling, M., "An IETF URN Sub-namespace for Registered
              Protocol Parameters", RFC 3553, June 2003.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              January 2004.

   [RFC4288]  Freed, N. and J. Klensin, "Media Type Specifications and
              Registration Procedures", BCP 13, RFC 4288, December 2005.

   [RFC4514]  Zeilenga, K., "Lightweight Directory Access Protocol
              (LDAP): String Representation of Distinguished Names",
              RFC 4514, June 2006.

   [XMLDSIG]  Eastlake, D., "XML-Signature Syntax and Processing",
              URL: http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/,
              W3C Recommendation, February 2002.

   [XMLENC]   Eastlake, D., "XML Encryption Syntax and Processing.",
              URL: http://www.w3.org/TR/xmlenc-core/, December 2002.

13.2.  Informative References

   [CAP]      MasterCard International, "Chip Authentication Program
              Functional Architecture", September 2004.




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   [DSKPP]    Doherty, A., Pei, M., Machani, S., and M. Nystrom,
              "Dynamic Symmetric Key Provisioning Protocol", Internet
              Draft Informational, URL: http://www.ietf.org/
              internet-drafts/draft-ietf-keyprov-dskpp-03.txt,
              February 2008.

   [HOTP]     MRaihi, D., Bellare, M., Hoornaert, F., Naccache, D., and
              O. Ranen, "HOTP: An HMAC-Based One Time Password
              Algorithm", RFC 4226,
              URL: http://rfc.sunsite.dk/rfc/rfc4226.html,
              December 2005.

   [NIST-SP800-57]
              National Institute of Standards and Technology,
              "Recommendation for Key Management - Part I: General
              (Revised)", NIST 800-57, URL: http://csrc.nist.gov/
              publications/nistpubs/800-57/
              sp800-57-Part1-revised2_Mar08-2007.pdf, March 2007.

   [OATH]     "Initiative for Open AuTHentication",
              URL: http://www.openauthentication.org.

   [OCRA]     MRaihi, D., Rydell, J., Naccache, D., Machani, S., and S.
              Bajaj, "OCRA: OATH Challenge Response Algorithm", Internet
              Draft Informational, URL: http://www.ietf.org/
              internet-drafts/
              draft-mraihi-mutual-oath-hotp-variants-06.txt,
              December 2007.

   [PKCS12]   RSA Laboratories, "PKCS #12: Personal Information Exchange
              Syntax Standard", Version 1.0,
              URL: http://www.rsasecurity.com/rsalabs/pkcs/.

   [Schneier]
              Schneier, B., "Secrets and Lies: Digitial Security in a
              Networked World",  Wiley Computer Publishing, ISBN 0-8493-
              8253-7, 2000.














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Authors' Addresses

   Philip Hoyer
   ActivIdentity, Inc.
   109 Borough High Street
   London, SE1  1NL
   UK

   Phone: +44 (0) 20 7744 6455
   Email: Philip.Hoyer@actividentity.com


   Mingliang Pei
   VeriSign, Inc.
   487 E. Middlefield Road
   Mountain View, CA  94043
   USA

   Phone: +1 650 426 5173
   Email: mpei@verisign.com


   Salah Machani
   Diversinet, Inc.
   2225 Sheppard Avenue East
   Suite 1801
   Toronto, Ontario  M2J 5C2
   Canada

   Phone: +1 416 756 2324 Ext. 321
   Email: smachani@diversinet.com




















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