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Authentication Context Certificate Extension
draft-santesson-auth-context-extension-12

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 7773.
Author Stefan Santesson
Last updated 2018-12-20 (Latest revision 2015-11-26)
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status Proposed Standard
Formats
Reviews
Stream WG state Submitted to IESG for Publication
Document shepherd Leif Johansson
Shepherd write-up Show Last changed 2015-10-12
IESG IESG state Became RFC 7773 (Proposed Standard)
Action Holders
(None)
Consensus boilerplate Yes
Telechat date (None)
Responsible AD Kathleen Moriarty
Send notices to stefan@aaa-sec.com, leifj@sunet.se
IANA IANA review state Version Changed - Review Needed
IANA action state No IANA Actions
draft-santesson-auth-context-extension-12
INTERNET-DRAFT                                          Stefan Santesson
Intended Status: Standards track                          (3xA Security)
Expires: May 29, 2016                                  November 26, 2015

              Authentication Context Certificate Extension
               draft-santesson-auth-context-extension-12

Abstract

   This document defines an extension to X.509 certificates. The
   extension defined in this document holds data about how the
   certificate subject was authenticated by the Certification Authority
   that issued the certificate in which this extension appears.

   This document also defines one data structure for inclusion in this
   Extension. The data structure is designed to hold information when
   the subject is authenticated using a Security Assertion Markup
   Language (SAML) assertion.

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as
   Internet-Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/1id-abstracts.html

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

Copyright and License Notice

   Copyright (c) 2015 IETF Trust and the persons identified as the
   document authors. All rights reserved.

 

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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document. Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1  Terminology . . . . . . . . . . . . . . . . . . . . . . . .  4
     1.2  Deployment  . . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Authentication Context Extension Syntax  . . . . . . . . . . .  5
   3  SAML Authentication Context Information . . . . . . . . . . . .  5
     3.1  contextInfo Data Structure  . . . . . . . . . . . . . . . .  6
       3.1.1   AuthContextInfo Element  . . . . . . . . . . . . . . .  6
       3.1.2  IdAttributes Element  . . . . . . . . . . . . . . . . .  8
   4  Security Considerations . . . . . . . . . . . . . . . . . . . . 10
   5  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 10
   6  References  . . . . . . . . . . . . . . . . . . . . . . . . . . 10
     6.1  Normative References  . . . . . . . . . . . . . . . . . . . 10
     6.2  Informative References  . . . . . . . . . . . . . . . . . . 11
   Appendix A - ASN.1 modules . . . . . . . . . . . . . . . . . . . . 11
     A.1  ASN.1 1988 Syntax . . . . . . . . . . . . . . . . . . . . . 11
     A.2  ASN.1 2008 Syntax . . . . . . . . . . . . . . . . . . . . . 12
   Appendix B - SAML Authentication Context Info XML Schema . . . . . 13
     B.1  XML Schema  . . . . . . . . . . . . . . . . . . . . . . . . 13
   Appendix C - SAML Authentication Context Info XML Examples . . . . 15
     C.1  Complete context information and mappings . . . . . . . . . 15
     C.2  Only mapping information without SAML attribute values  . . 16
     C.3  Authentication context and serialNmber mapping  . . . . . . 17
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18

 

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1  Introduction

   The primary purpose of this document is to provide a mechanism that
   allows an application to obtain information that expresses the
   identity of a subject in an X.509 certificate according to [RFC5280].
   The identity is stored either in a subject field attribute, as a
   subject alternative name, or in a subject directory attribute.

   The motivation for this work is to enable mapping of identity data
   between an identity system and a certificate where the identity
   system and the certificate are using different attributes and data
   formats to express the identity of the same entity. In such scenario,
   the certificate subject already has an authenticated identity
   composed of a set of attributes, or so called claims, that differ
   from the attributes commonly used to express the identity of a
   certificate subject, which may be governed by a specific certificate
   profile limiting the set of certificate attributes.

   A typical scenario motivating the definition of this extension arises
   when the source of user authentication and user identity is derived
   from a SAML [SAML] federation attribute profile. In a SAML
   federation, the subject presents a SAML assertion in exchange for a
   certificate that can be uniquely linked to information provided in
   the original SAML assertion - eg attributes and/or level of assurance
   indicators.

   Such certificates are sometimes issued in order to provide the user
   with a means to create an electronic signature that ties the user to
   the SAML subject, its attributes and level of assurance indicators.

   If such certificate needs to conform to a certificate profile such as
   [RFC3739], then this certificate may have to use a separate set of
   attributes to express the subject identity. The certificate also may
   have to employ a different format for attribute values, vs. the set
   of attributes obtained from the SAML assertion.

   The extension defined in the document makes it possible to represent
   information about the authentication context employed when
   authenticating the subject for the purpose of issuing a certificate.
   This may include information such as:

     o  The Identity Provider that authenticated the subject.
     o  The level of assurance with which the subject was authenticated.
     o  The trust framework where this level of assurance was defined.
     o  A unique reference to the authentication instant
     o  A mapping between the subject attributes obtained from the SAML
        assertion used to authenticate the subject, and the subject
        identity information placed in the issued certificate.
 

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   One scenario where this information may be useful arises when a user
   logs in to a service using SAML credentials, and the same user (at
   some point) is required to sign some information. The service may
   need to verify that the signature was created by the same user that
   logged on to the service. Today this is only possible using out-of-
   band knowledge about the Certification Authority (CA) that issued the
   certificate and it's practices. However, this approach does not scale
   to a large number of service providers, identity providers, and CAs.

   The extension defined here provides better scalability since it
   requires only the service provider to maintain a list of trusted CAs.
   All other information about the relationship between the certificate
   subject, and the SAML authenticated subject is available in the
   certificate.

1.1  Terminology

   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 RFC 2119 [RFC2119].

1.2  Deployment

   EDITORS NOTE:
      [This section provided information for better understanding the
      rationale of the extension. This section can be deleted when the
      document is published]

   The extension described in this draft has been defined and deployed
   in the National Swedish Identity infrastructure (eID) which is based
   on SAML federated identity. The Swedish infrastructure went live in
   2013 and provides secure identification of citizens for Swedish
   government services. A central requirement in these government
   services is to allow citizens to sign various documents, representing
   a wide range of declarations and applications.

   A central part of this infrastructure is therefore to use centralized
   signature services that allows citizens to sign based on their SAML
   credentials. Service providers authenticate and understand user
   identities only under a SAML context within this national
   infrastructure. Thus this extension allows Service Providers to
   determine whether a presented signature matches a particular user and
   whether it meets the security requirements of the service.

   Through information provided in this extension a service provider
   may, for example, receive notice that the user logged on using one
   level of assurance, but presented a signature verifiable using a
   certificate obtained using a lower level of assurance. In such
 

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   circumstances the service provider might reject the signature.

   This extension is therefore fundamental to the function of the
   Swedish eID infrastructure.

2.  Authentication Context Extension Syntax

   The Authentication Context extension has the following syntax:

      AuthenticationContexts ::= SEQUENCE SIZE (1..MAX) OF
                                 AuthenticationContext

      AuthenticationContext ::= SEQUENCE {
          contextType     UTF8String,
          contextInfo     UTF8String OPTIONAL
      }

   This extension holds a sequence of AuthenticationContext information.
   When present, this extension MUST include at least one
   AuthenticationContext.

   The type of authentication context defined in AuthenticationContext
   is identified by the contextType. The contextType MUST contain a URI
   that identifies the context type as well as data format and encoding
   of context information provided in contextInfo.

   This extension MAY be marked critical.

   Applications that find an authentication context information type
   they do not understand MUST ignore it if the extension is non-
   critical, and MUST reject the certificate if the extension is marked
   critical. If an application requires that an authentication context
   exist, and either the extension is absent, or none of the provided
   authentication contexts can be used, the end user certificate fails
   validation.

   This document defines one authentication context information type
   (Section 3) that is used to provide information about SAML based
   authentication of the subject that was utilized in the certificate
   issuance process. Other documents can define other authentication
   context information types.

3  SAML Authentication Context Information

   The SAML Authentication context information provides a contextType
 

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   field that can be used to carry information about SAML-based
   authentication of the certified subject as utilized in the
   certificate issuance process.

   The data carried in this authentication context information field is
   identified by the following XML Schema [Schema1] and [Schema2] name
   space:

      http://id.elegnamnden.se/auth-cont/1.0/saci

   When this URI is specified as contextType, the associated XML data
   provided in contextInfo MUST be provided as an UTF-8 encoded XML
   [XML] string.

3.1  contextInfo Data Structure

   The data provided in contextInfo SHALL contain UTF-8 encoded XML in
   accordance with the XML schema provided in Appendix B. The XML
   document string in contextInfo MUST NOT include an XML header. That
   is, the XML document string contains only the root element
   <SAMLAuthContext> with it's child elements <AuthContextInfo> and
   <IdAttributes>.

   The <AuthContextInfo> and <IdAttributes> elements are outlined in the
   following subsections.

3.1.1   AuthContextInfo Element

   The <AuthContextInfo> element MAY be present. This element contains
   the following attributes:

     IdentityProvider       (required): The SAML EntityID of the
                            Identity Provider which authenticated the
                            subject.
     AuthenticationInstant  (required): Date and time when the subject
                            was authenticated, expressed according to
                            Appendix B.1.
     AuthnContextClassRef   (required): A URI identifying the
                            AuthnContextClassRef that is provided in the
                            AuthnStatement of the Assertion that was
                            used to authenticate the subject. This URI
                            identifies the context and the level of
                            assurance associated with this instance of
                            authentication.
     AssertionRef           (optional): A unique reference to the SAML
                            Assertion
 

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     ServiceID              (optional): An identifier of the service
                            that verified the SAML assertion.

   The <AuthContextInfo> element may hold any number of child elements
   of type any (processContents="lax"), providing additional information
   according to local conventions. Any such elements SHOULD be ignored
   if not understood.

 

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3.1.2  IdAttributes Element

   The <IdAttributes> element MAY be present. This element holds a
   sequence of one or more <AttributeMapping> elements, where each
   <AttributeMapping> element contains mapping information about one
   certificate subject attribute or name form present in the
   certificate.

   Each <AttributeMapping> element MUST specify the following
   attributes:

     Type   A string containing one of the enumerated values "rdn",
            "san" or "sda", specifying the type of certificate attribute
            or name form for which mapping information is provided:

              "rdn"  Mapping information is provided for an attribute in
                     a Relative Distinguished Name located in the
                     subject field.
              "san"  Mapping information is provided for a name in the
                     Subject Alternative Name extension of the
                     certificate.
              "sda"  Mapping information is provided for an attribute in
                     the Subject Directory Attributes extension.

     Ref    A reference to the specific attribute or name field. This
            reference is dependent on the value of Type in the following
            way:

              "rdn"  Ref holds a string representation of the object
                     identifier (OID) of the relative distinguished name
                     attribute.
              "sda"  Ref holds a string representation of the OID of the
                     subject directory attribute attribute.
              "san"  Ref holds a string representation of the explicit
                     tag number of the Subject Alternative Name type
                     (e.g. "1" = e-mail address (rfc822Name) and "2" =
                     dNSName). If the SubjectAlternative name is an
                     otherName, then Ref holds a string representation
                     of the OID defining the otherName form.

            String representations of object identifiers (OID) in the
            Ref attribute MUST be represented by a sequence of integers
            separated by a period. E.g. "2.5.4.32". This string contains
            only numerals (ASCII 0x30 to 0x39) and periods (ASCII 0x2E),
            and MUST NOT contain any other characters.

   Each <AttributeMapping> element MUST contain a <saml:Attribute>
   element as defined in [SAML]. This SAML attribute element MUST have a
 

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   Name attribute (specifying its type), MAY have other attributes and
   MAY have zero or more <saml:AttributeValue> child elements. A present
   SAML attribute with absent attribute value limits mapping to the type
   of SAML attribute that was used to obtain the value stored in the
   referenced certificate subject attribute or name form, without
   duplicating the actual attribute value.

   If an attribute value is present in the SAML attribute, then the
   value stored in the certificate in the referenced attribute or name
   form MAY differ in format and encoding from the present SAML
   attribute value. For example, a SAML attribute value can specify a
   country expressed as "Sweden" while this country value is stored in
   the certificate in a countryName attribute using the two letter
   country code "SE". 

   Several <AttributeMapping> elements MAY be present for the same
   certificate subject attribute or name form if the certificate
   contains multiple instances of this attribute or name form where
   their values were obtained from different SAML attributes. But in
   such cases it is not defined which present subject attribute or name
   form maps to which SAML attribute. A certificate-using application
   MAY attempt to determine this by comparing attribute values stored in
   this extension with attribute or name values present in the
   certificate, but this specification does not define any explicit
   matching rules that would guarantee an unambiguous result.

   The <AttributeMapping> element may hold any number of child elements
   of type any (processContents="lax"), providing additional information
   according to local conventions. Any such elements MAY be ignored if
   not understood.

   Note: The <AttributeMapping> element is designed to provide mapping
         between SAML attributes and certificate subject attributes and
         name forms where there is a distinct and clear relationship
         between relevant SAML attributes and corresponding certificate
         attributes and name forms. This does not cover all aspects of
         complex mapping situations. If more than one SAML attribute
         maps to the same certificate attribute or if structured multi
         valued attributes are split into a range of other attributes
         and name forms, these situations are not covered. Such complex
         mapping situations MAY be covered by extending this XML Schema
         or by defining a more versatile context information schema.

 

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4  Security Considerations

   This extension allows a CA to outsource the process used to identify
   and authenticate a subject to another trust infrastructure in a
   dynamic manner that may differ from certificate to certificate. Since
   the authentication context is explicitly declared in the certificate,
   one certificate may be issued with a lower level of assurance than
   another, even though both have the same Issuer.

   This means that a relying party needs to be aware of the certificate
   policy under which this CA operates in order to understand when the
   certificate provides a level of assurance with regard to subject
   authentication that is higher than the lowest provided level. A
   relying party that is not capable of understanding the information in
   the authentication context extension MUST assume that the certificate
   is issued using the lowest allowed level of assurance declared by the
   policy.

5  IANA Considerations

   This document contains no actions for IANA.

6  References

6.1  Normative References

   [RFC2119]      Bradner, S., "Key words for use in RFCs to Indicate
                  Requirement Levels", BCP 14, RFC 2119, DOI
                  10.17487/RFC2119, March 1997, <http://www.rfc-
                  editor.org/info/rfc2119>.

   [RFC3739]      Santesson, S., Nystrom, M., and T. Polk, "Internet
                  X.509 Public Key Infrastructure: Qualified
                  Certificates Profile", RFC 3739, DOI 10.17487/RFC3739,
                  March 2004, <http://www.rfc-editor.org/info/rfc3739>.

   [RFC5280]      Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
                  Housley, R., and W. Polk, "Internet X.509 Public Key
                  Infrastructure Certificate and Certificate Revocation
                  List (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280,
                  May 2008, <http://www.rfc-editor.org/info/rfc5280>.

   [RFC5912]      Hoffman, P. and J. Schaad, "New ASN.1 Modules for the
                  Public Key Infrastructure Using X.509 (PKIX)",
                  RFC 5912, DOI 10.17487/RFC5912, June 2010,
                  <http://www.rfc-editor.org/info/rfc5912>.

 

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   [SAML]         Scot Cantor, John Kemp, Rob Philpott, Eve Maler,
                  "Assertions and Protocols for the OASIS Security
                  Assertion Markup Language (SAML) V2.0", OASIS
                  Standard, 15 March 2005.

   [XML]          Extensible Markup Language (XML) 1.0 (Fifth Edition),
                  http://www.w3.org/TR/REC-xml/#sec-element-content, W3C
                  Recommendation 26 November 2008.

   [Schema1]      H. S. Thompson et al. XML Schema Part 1: Structures,
                  http://www.w3.org/TR/xmlschema-1/, W3C Recommendation,
                  May 2001.

   [Schema2]      P. V. Biron et al. XML Schema Part 2: Datatypes.
                  http://www.w3.org/TR/xmlschema-2/ , W3C
                  Recommendation, May 2001.

6.2  Informative References

   No informational references

Appendix A - ASN.1 modules

   This appendix includes the ASN.1 modules for the Authentication
   Context extension.  Appendix B.1 includes an ASN.1 module that
   conforms to the 1998 version of ASN.1. Appendix B.2 includes an ASN.1
   module, corresponding to the module present in B.1, that conforms to
   the 2008 version of ASN.1. Although a 2008 ASN.1 module is provided,
   the module in Appendix B.1 remains the normative module as per policy
   adopted by the PKIX working group for certificate related
   specifications.

A.1  ASN.1 1988 Syntax

 ACE-88
       {iso(1) member-body(2) se(752) e-legnamnden(201)
        id-mod(0) id-mod-auth-context-88(1)}

 DEFINITIONS EXPLICIT TAGS ::=

 BEGIN

 -- EXPORTS ALL --

 -- Authentication Context Extension

 

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 AuthenticationContexts ::= SEQUENCE SIZE (1..MAX) OF  
                            AuthenticationContext

 AuthenticationContext ::= SEQUENCE {
     contextType     UTF8String,
     contextInfo     UTF8String OPTIONAL
 }

 e-legnamnden      OBJECT IDENTIFIER ::= { iso(1) member-body(2)
                                           se(752) 201 }
 id-eleg-ce        OBJECT IDENTIFIER ::= { e-legnamnden 5 }
 id-ce-authContext OBJECT IDENTIFIER ::= { id-eleg-ce 1 }

 END

A.2  ASN.1 2008 Syntax

 ACE-08
       {iso(1) member-body(2) se(752) e-legnamnden(201)
        id-mod(0) id-mod-auth-context-08(2)}

 DEFINITIONS EXPLICIT TAGS ::=
 BEGIN
 EXPORTS ALL;
 IMPORTS

 Extensions{}, EXTENSION
 FROM PKIX-CommonTypes-2009 -- From [RFC5912]
     {iso(1) identified-organization(3) dod(6) internet(1) security(5)
     mechanisms(5) pkix(7) id-mod(0) id-mod-pkixCommon-02(57)};

 -- Authentication Context Extension

 ext-AuthenticationContext EXTENSION ::= { SYNTAX
        AuthenticationContexts IDENTIFIED BY
        id-ce-authContext }

 AuthenticationContexts ::= SEQUENCE SIZE (1..MAX) OF  
                            AuthenticationContext

 AuthenticationContext ::= SEQUENCE {
     contextType     UTF8String,
     contextInfo     UTF8String OPTIONAL
 }

 ElegnamndenCertExtensions EXTENSION ::= {
     ext-AuthenticationContext, ... }

 

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 e-legnamnden      OBJECT IDENTIFIER ::= { iso(1) member-body(2)
                                           se(752) 201 }
 id-eleg-ce        OBJECT IDENTIFIER ::= { e-legnamnden 5 }
 id-ce-authContext OBJECT IDENTIFIER ::= { id-eleg-ce 1 }

 END

Appendix B - SAML Authentication Context Info XML Schema

 This appendix section B.1 includes an XML Schema ([Schema1] and
 [Schema2]) for the SAML Authentication context information defined in
 section 3.

 IMPORTANT NOTE: The XML Schema in B.1 specifies a URL on row 9 and 10
                 to the SAML schemaLocation (http://docs.oasis-
                 open.org/security/saml/v2.0/saml-schema-assertion-
                 2.0.xsd), which is too long to fit into one row and
                 therefore contains a line-break. This line-break has to
                 be removed before this schema can be successfully
                 compiled.

B.1  XML Schema

 <?xml version="1.0" encoding="UTF-8"?>
 <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" 
            elementFormDefault="qualified"
     targetNamespace="http://id.elegnamnden.se/auth-cont/1.0/saci"
     xmlns:saci="http://id.elegnamnden.se/auth-cont/1.0/saci"
     xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">

     <xs:import namespace="urn:oasis:names:tc:SAML:2.0:assertion"
         schemaLocation="http://docs.oasis-open.org/security/saml/v2.0/
 saml-schema-assertion-2.0.xsd"/>

     <xs:element name="SAMLAuthContext" 
                 type="saci:SAMLAuthContextType"/>
     <xs:complexType name="SAMLAuthContextType">
         <xs:sequence>
             <xs:element ref="saci:AuthContextInfo" minOccurs="0"/>
             <xs:element ref="saci:IdAttributes" minOccurs="0"/>
         </xs:sequence>
     </xs:complexType>
     <xs:element name="AuthContextInfo" 
                 type="saci:AuthContextInfoType"/>
     <xs:complexType name="AuthContextInfoType">
         <xs:sequence>
             <xs:any processContents="lax"
 

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                 minOccurs="0" maxOccurs="unbounded"/>
         </xs:sequence>
         <xs:attribute name="IdentityProvider" 
                       type="xs:string" use="required"/>
         <xs:attribute name="AuthenticationInstant" 
                       type="xs:dateTime" use="required"/>
         <xs:attribute name="AuthnContextClassRef" 
                       type="xs:anyURI" use="required"/>
         <xs:attribute name="AssertionRef" type="xs:string"/>
         <xs:attribute name="ServiceID" type="xs:string"/>
     </xs:complexType>

     <xs:element name="IdAttributes" type="saci:IdAttributesType"/>
     <xs:complexType name="IdAttributesType">
         <xs:sequence>
             <xs:element maxOccurs="unbounded" minOccurs="1" 
                         ref="saci:AttributeMapping"/>
         </xs:sequence>
     </xs:complexType>
     <xs:element name="AttributeMapping" 
                 type="saci:AttributeMappingType"/>
     <xs:complexType name="AttributeMappingType">
         <xs:sequence>
             <xs:element ref="saml:Attribute"/>
             <xs:any processContents="lax"
                 minOccurs="0" maxOccurs="unbounded"/>
         </xs:sequence>
         <xs:attribute name="Type" use="required">
             <xs:simpleType>
                 <xs:restriction base="xs:string">
                     <xs:enumeration value="rdn"/>
                     <xs:enumeration value="san"/>
                     <xs:enumeration value="sda"/>
                 </xs:restriction>
             </xs:simpleType>
         </xs:attribute>
         <xs:attribute name="Ref" type="xs:string" use="required"/>
     </xs:complexType>
 </xs:schema>

 

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Appendix C - SAML Authentication Context Info XML Examples

This appendix provides examples of SAML Authentication Context
information according to the schema in Appendix B.

C.1  Complete context information and mappings

This example provides a complete example with authentication context
information as well as mapping information for several subject field
attributes as well as a subject alt name.

<saci:SAMLAuthContext
    xmlns:saci="http://id.elegnamnden.se/auth-cont/1.0/saci"
    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <saci:AuthContextInfo
        ServiceID="eid2csig"
        AssertionRef="_71b981ab017eb42869ae4b62b2a63add"
        IdentityProvider="https://idp-test.nordu.net/idp/shibboleth"
        AuthenticationInstant="2013-03-05T22:59:57.000+01:00"
        AuthnContextClassRef="http://id.elegnamnden.se/loa/1.0/loa3"/>
    <saci:IdAttributes>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.6">
            <saml:Attribute 
                FriendlyName="Country" 
                Name="urn:oid:2.5.4.6">
                <saml:AttributeValue xsi:type="xs:string"
                    >SE</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.5">
            <saml:Attribute 
                FriendlyName="Personal ID Number" 
                Name="urn:oid:1.2.752.29.4.13">
                <saml:AttributeValue xsi:type="xs:string"
                    >200007292386</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.42">
            <saml:Attribute 
                FriendlyName="Given Name" 
                Name="urn:oid:2.5.4.42">
                <saml:AttributeValue xsi:type="xs:string"
                    >John</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.4">
            <saml:Attribute 
 

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                FriendlyName="Surename" 
                Name="urn:oid:2.5.4.4">
                <saml:AttributeValue xsi:type="xs:string"
                    >Doe</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.3">
            <saml:Attribute 
                FriendlyName="Display Name" 
                Name="urn:oid:2.16.840.1.113730.3.1.241">
                <saml:AttributeValue xsi:type="xs:string"
                    >John Doe</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="san" Ref="1">
            <saml:Attribute 
                FriendlyName="E-mail" 
                Name="urn:oid:0.9.2342.19200300.100.1.3">
                <saml:AttributeValue xsi:type="xs:string"
                    >john.doe@example.com</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
    </saci:IdAttributes>
</saci:SAMLAuthContext>

C.2  Only mapping information without SAML attribute values

This example shows an instance of the SAML Authentication Context
information that only provides a mapping table without providing any
authentication context information or saml attribute values.

<saci:SAMLAuthContext
    xmlns:saci="http://id.elegnamnden.se/auth-cont/1.0/saci"
    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion">
    <saci:IdAttributes>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.6">
            <saml:Attribute Name="urn:oid:2.5.4.6"/>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.5">
            <saml:Attribute Name="urn:oid:1.2.752.29.4.13"/>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.42">
            <saml:Attribute Name="urn:oid:2.5.4.42"/>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.4">
            <saml:Attribute Name="urn:oid:2.5.4.4"/>
        </saci:AttributeMapping>
 

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        <saci:AttributeMapping Type="rdn" Ref="2.5.4.3">
            <saml:Attribute Name="urn:oid:2.16.840.1.113730.3.1.241"/>
        </saci:AttributeMapping>
        <saci:AttributeMapping Type="san" Ref="1">
            <saml:Attribute Name="urn:oid:0.9.2342.19200300.100.1.3"/>
        </saci:AttributeMapping>
    </saci:IdAttributes>
</saci:SAMLAuthContext>

C.3  Authentication context and serialNmber mapping

This example shows an instance of the SAML Authentication Context
information, which provides authentication context information and
mapping information that specifies the source of the data stored in the
serialNumber attribute in the subject field.

<saci:SAMLAuthContext
    xmlns:saci="http://id.elegnamnden.se/auth-cont/1.0/saci"
    xmlns:saml="urn:oasis:names:tc:SAML:2.0:assertion"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <saci:AuthContextInfo
        ServiceID="eid2csig"
        AssertionRef="_71b981ab017eb42869ae4b62b2a63add"
        IdentityProvider="https://idp-test.nordu.net/idp/shibboleth"
        AuthenticationInstant="2013-03-05T22:59:57.000+01:00"
        AuthnContextClassRef="http://id.elegnamnden.se/loa/1.0/loa3"/>
    <saci:IdAttributes>
        <saci:AttributeMapping Type="rdn" Ref="2.5.4.5">
            <saml:Attribute 
                FriendlyName="Personal ID Number" 
                Name="urn:oid:1.2.752.29.4.13">
                <saml:AttributeValue xsi:type="xs:string"
                    >200007292386</saml:AttributeValue>
            </saml:Attribute>
        </saci:AttributeMapping>
    </saci:IdAttributes>
</saci:SAMLAuthContext>

 

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Authors' Addresses

   Stefan Santesson
   3xA Security AB
   Scheelev. 17
   223 70 Lund
   Sweden
   EMail: sts@aaa-sec.com

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