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Versions: 00 01 02 03

Network Working Group                                           O. Friel
Internet-Draft                                                     Cisco
Intended status: Standards Track                          R. Shekh-Yusef
Expires: 28 March 2021                                             Auth0
                                                           M. Richardson
                                                Sandelman Software Works
                                                       24 September 2020


                         BRSKI Cloud Registrar
                    draft-friel-anima-brski-cloud-03

Abstract

   This document specifies the behaviour of a BRSKI Cloud Registrar, and
   how a pledge can interact with a BRSKI Cloud Registrar when
   bootstrapping.

   RFCED REMOVE: It is being actively worked on at https://github.com/
   anima-wg/brski-cloud

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   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."

   This Internet-Draft will expire on 28 March 2021.

Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://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



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   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     1.2.  Target Use Cases  . . . . . . . . . . . . . . . . . . . .   3
       1.2.1.  Owner Registrar Discovery . . . . . . . . . . . . . .   4
       1.2.2.  Bootstrapping with no Owner Registrar . . . . . . . .   4
   2.  Architecture  . . . . . . . . . . . . . . . . . . . . . . . .   4
     2.1.  Interested Parties  . . . . . . . . . . . . . . . . . . .   5
     2.2.  Network Connectivity  . . . . . . . . . . . . . . . . . .   6
     2.3.  Pledge Certificate Identity Considerations  . . . . . . .   6
   3.  Protocol Operation  . . . . . . . . . . . . . . . . . . . . .   6
     3.1.  Pledge Requests Voucher from Cloud Registrar  . . . . . .   6
       3.1.1.  Cloud Registrar Discovery . . . . . . . . . . . . . .   6
       3.1.2.  Pledge - Cloud Registrar TLS Establishment Details  .   7
       3.1.3.  Pledge Issues Voucher Request . . . . . . . . . . . .   7
     3.2.  Cloud Registrar Handles Voucher Request . . . . . . . . .   7
       3.2.1.  Pledge Ownership Lookup . . . . . . . . . . . . . . .   8
       3.2.2.  Cloud Registrar Redirects to Owner Registrar  . . . .   8
       3.2.3.  Cloud Registrar Issues Voucher  . . . . . . . . . . .   8
     3.3.  Pledge Handles Cloud Registrar Response . . . . . . . . .   9
       3.3.1.  Redirect Response . . . . . . . . . . . . . . . . . .   9
       3.3.2.  Voucher Response  . . . . . . . . . . . . . . . . . .   9
   4.  Protocol Details  . . . . . . . . . . . . . . . . . . . . . .   9
     4.1.  Voucher Request Redirected to Local Domain Registrar  . .   9
     4.2.  Voucher Request Handled by Cloud Registrar  . . . . . . .  11
   5.  YANG extension for Voucher based redirect . . . . . . . . . .  13
     5.1.  YANG Tree . . . . . . . . . . . . . . . . . . . . . . . .  13
     5.2.  YANG Voucher  . . . . . . . . . . . . . . . . . . . . . .  14
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  16
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  16
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  16
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  16
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  17
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  17

1.  Introduction

   Bootstrapping Remote Secure Key Infrastructures (BRSKI)
   [I-D.ietf-anima-bootstrapping-keyinfra] specifies automated
   bootstrapping of an Autonomic Control Plane.  BRSKI Section 2.7
   describes how a pledge "MAY contact a well known URI of a cloud
   registrar if a local registrar cannot be discovered or if the
   pledge's target use cases do not include a local registrar".



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   This document further specifies use of a BRSKI cloud registrar and
   clarifies operations that are not sufficiently specified in BRSKI.

1.1.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   This document uses the terms Pledge, Registrar, MASA, and Voucher
   from [I-D.ietf-anima-bootstrapping-keyinfra] and [RFC8366].

   *  Local Domain: The domain where the pledge is physically located
      and bootstrapping from.  This may be different to the pledge
      owner's domain.

   *  Owner Domain: The domain that the pledge needs to discover and
      bootstrap with.

   *  Cloud Registrar: The default Registrar that is deployed at a URI
      that is well known to the pledge.

   *  Owner Registrar: The Registrar that is operated by the Owner, or
      the Owner's delegate.  There may not be an Owner Registrar in all
      deployment scenarios.

   *  Local Domain Registrar: The Registrar discovered on the Local
      Domain.  There may not be a Local Domain Registrar in all
      deployment scenarios.

1.2.  Target Use Cases

   Two high level use cases are documented here.  There are more details
   provided in sections Section 4.1 and Section 4.2.  While both use
   cases aid with incremental deployment of BRSKI infrastructure, for
   many smaller sites (such as teleworkers) no further infrastructure
   are expected.

   The pledge is not expected to know which of these two situations it
   is in.  The pledge determines this based upon signals that it
   receives from the Cloud Registrar.  The Cloud Registrar is expected
   to make the determination based upon the identity presented by the
   pledge.






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   While a Cloud Registrar will typically handle all the devices of a
   particular product line from a particular manufacturer there are no
   restrictions on how the Cloud Registrar is horizontally (many sites)
   or vertically (more equipment at one site) scaled.  It is also
   entirely possible that all devices sold by through a particular VAR
   might be preloaded with a configuration that changes the Cloud
   Registrar URL to point to a VAR.  Such an effort would require
   unboxing each device in a controlled environment, but the
   provisioning could occur using a regular BRSKI or SZTP [RFC8572]
   process.

1.2.1.  Owner Registrar Discovery

   A pledge is bootstrapping from a remote location with no local domain
   registrar (specifically: with no local infrastructure to provide for
   automated discovery), and needs to discover its owner registrar.  The
   cloud registrar is used by the pledge to discover the owner
   registrar.  The cloud registrar redirects the pledge to the owner
   registrar, and the pledge completes bootstrap against the owner
   registrar.

   A typical example is an enduser deploying a pledge in a home or small
   branch office, where the pledge belongs to the enduser's employer.
   There is no local domain registrar, and the pledge needs to discover
   and bootstrap with the employer's registrar which is deployed in
   headquarters.

1.2.2.  Bootstrapping with no Owner Registrar

   A pledge is bootstrapping where the owner organization does not yet
   have an owner registrar deployed.  The cloud registrer issues a
   voucher, and the pledge completes trust bootstrap using the cloud
   registrar.  The voucher issued by the cloud includes domain
   information for the owner's EST [RFC7030] service the pledge should
   use for certificate enrollment.

   In one use case, an organization has an EST service deployed, but
   does not have yet a BRSKI capable Registrar service deployed.  The
   pledge is deployed in the organizations domain, but does not discover
   a local domain, or owner, registrar.  The pledge uses the cloud
   registrar to bootstrap, and the cloud registrar provides a voucher
   that includes instructions on finding the organization's EST service.

2.  Architecture

   The high level architecture is illustrated in Figure 1.

   The pledge connects to the cloud registrar during bootstrap.



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   The cloud registrar may redirect the pledge to an owner registrar in
   order to complete bootstrap against the owner registrar.

   If the cloud registrar issues a voucher itself without redirecting
   the pledge to an owner registrar, the cloud registrar will inform the
   pledge what domain to use for accessing EST services in the voucher
   response.

   Finally, when bootstrapping against an owner registrar, this
   registrar may interact with a backend CA to assist in issuing
   certificates to the pledge.  The mechanisms and protocols by which
   the registrar interacts with the CA are transparent to the pledge and
   are out-of-scope of this document.

   The architecture shows the cloud registrar and MASA as being
   logically separate entities.  The two functions could of course be
   integrated into a single service.

   TWO CHOICES: 1.  Cloud Registrar redirects to Owner Registrar 2.
   Cloud Registrar returns VOUCHER pinning Owner Register.

   |<--------------OWNER------------------------>|     MANUFACTURER

    On-site                Cloud
   +--------+                                         +-----------+
   | Pledge |---------------------------------------->| Cloud     |
   +--------+                                         | Registrar |
       |                                              +---+  +----+
       |                                                  |??|
       |                 +-----------+                +---+  +----+
       +---------------->|  Owner    |--------------->|   MASA    |
       |   VR-sign(N)    | Registrar |sign(VR-sign(N))+-----------+
       |                 +-----------+
       |                       |    +-----------+
       |                       +--->|    CA     |
       |                            +-----------+
       |
       |                 +-----------+
       +---------------->| Services  |
                         +-----------+

                     Figure 1: High Level Architecture

2.1.  Interested Parties

   1.  OEM - Equipment manufacturer.  Operate the MASA.





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   2.  Network operator.  Operate the Owner Registrar.  Often operated
       by end owner (company), or by outsourced IT entity.

   3.  Network integrator.  They operate a Cloud Registrar.

2.2.  Network Connectivity

   The assumption is that the pledge already has network connectivity
   prior to connecting to the cloud registrar.  The pledge must have an
   IP address, must be able to make DNS queries, and must be able to
   send HTTP requests to the cloud registrar.  The pledge operator has
   already connected the pledge to the network, and the mechanism by
   which this has happened is out of scope of this document.

2.3.  Pledge Certificate Identity Considerations

   BRSKI section 5.9.2 specifies that the pledge MUST send a CSR
   Attributes request to the registrar.  The registrar MAY use this
   mechanism to instruct the pledge about the identities it should
   include in the CSR request it sends as part of enrollment.  The
   registrar may use this mechanism to tell the pledge what Subject or
   Subject Alternative Name identity information to include in its CSR
   request.  This can be useful if the Subject must have a specific
   value in order to complete enrollment with the CA.

   For example, the pledge may only be aware of its IDevID Subject which
   includes a manufacturer serial number, but must include a specific
   fully qualified domain name in the CSR in order to complete domain
   ownership proofs required by the CA.

   As another example, the registrar may deem the manufacturer serial
   number in an IDevID as personally identifiable information, and may
   want to specify a new random opaque identifier that the pledge should
   use in its CSR.

3.  Protocol Operation

3.1.  Pledge Requests Voucher from Cloud Registrar

3.1.1.  Cloud Registrar Discovery

   BRSKI defines how a pledge MAY contact a well known URI of a cloud
   registrar if a local domain registrar cannot be discovered.
   Additionally, certain pledge types may never attempt to discover a
   local domain registrar and may automatically bootstrap against a
   cloud registrar.





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   The details of the URI are manufacturer specific, with BRSKI giving
   the example "brski-registrar.manufacturer.example.com".

   The Pledge SHOULD be provided with the entire URL of the Cloud
   Registrar, including the path component, which is typically "/.well-
   known/brski/requestvoucher", but may be another value.

3.1.2.  Pledge - Cloud Registrar TLS Establishment Details

   The pledge MUST use an Implicit Trust Anchor database (see [RFC7030])
   to authenticate the cloud registrar service.  The Pledge can be done
   with pre-loaded trust-anchors that are used to validate the TLS
   connection.  This can be using a public Web PKI trust anchors using
   [RFC6125] DNS-ID mechanisms, a pinned certification authority, or
   even a pinned raw public key.  This is a local implementation
   decision.

   The pledge MUST NOT establish a provisional TLS connection (see BRSKI
   section 5.1) with the cloud registrar.

   The cloud registrar MUST validate the identity of the pledge by
   sending a TLS CertificateRequest message to the pledge during TLS
   session establishment.  The cloud registrar MAY include a
   certificate_authorities field in the message to specify the set of
   allowed IDevID issuing CAs that pledges may use when establishing
   connections with the cloud registrar.

   The cloud registrar MAY only allow connections from pledges that have
   an IDevID that is signed by one of a specific set of CAs, e.g.
   IDevIDs issued by certain manufacturers.

   The cloud registrar MAY allow pledges to connect using self-signed
   identity certificates or using Raw Public Key [RFC7250] certificates.

3.1.3.  Pledge Issues Voucher Request

   After the pledge has established a full TLS connection with the cloud
   registrar and has verified the cloud registrar PKI identity, the
   pledge generates a voucher request message as outlined in BRSKI
   section 5.2, and sends the voucher request message to the cloud
   registrar.

3.2.  Cloud Registrar Handles Voucher Request

   The cloud registrar must determine pledge ownership.  Once ownership
   is determined, or if no owner can be determined, then the registrar
   may:




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   *  return a suitable 4xx or 5xx error response to the pledge if the
      registrar is unwilling or unable to handle the voucher request

   *  redirect the pledge to an owner register via 307 response code

   *  issue a voucher and return a 200 response code

3.2.1.  Pledge Ownership Lookup

   The cloud registrar needs some suitable mechanism for knowing the
   correct owner of a connecting pledge based on the presented identity
   certificate.  For example, if the pledge establishes TLS using an
   IDevID that is signed by a known manufacturing CA, the registrar
   could extract the serial number from the IDevID and use this to
   lookup a database of pledge IDevID serial numbers to owners.

   Alternatively, if the cloud registrar allows pledges to connect using
   self-signed certificates, the registrar could use the thumbprint of
   the self-signed certificate to lookup a database of pledge self-
   signed certificate thumbprints to owners.

   The mechanism by which the cloud registrar determines pledge
   ownership is out-of-scope of this document.

3.2.2.  Cloud Registrar Redirects to Owner Registrar

   Once the cloud registar has determined pledge ownership, the cloud
   registrar may redirect the pledge to the owner registrar in order to
   complete bootstrap.  Ownership registration will require the owner to
   register their local domain.  The mechanism by which pledge owners
   register their domain with the cloud registrar is out-of-scope of
   this document.

   The cloud registrar replies to the voucher request with a suitable
   HTTP 307 response code, including the owner's local domain in the
   HTTP Location header.

3.2.3.  Cloud Registrar Issues Voucher

   If the cloud registrar issues a voucher, it returns the voucher in a
   HTTP response with a 200 response code.

   The cloud registrar MAY issue a 202 response code if it is willing to
   issue a voucher, but will take some time to prepare the voucher.

   The voucher MUST include the "est-domain" field as defined below.
   This tells the pledge where the domain of the EST service to use for
   completing certificate enrollment.



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   The voucher MAY include the "additional-configuration" field.. This
   points the pledge to a URI where application specific additional
   configuration information may be retrieved.  Pledge and Registrar
   behavior for handling and specifying the "additional-configuration"
   field is out-of-scope of this document.

3.3.  Pledge Handles Cloud Registrar Response

3.3.1.  Redirect Response

   The cloud registrar returned a 307 response to the voucher request.
   The pledge should complete BRSKI bootstrap as per standard BRSKI
   operation after following the HTTP redirect.  The pledge should
   establish a provisional TLS connection with specified local domain
   registrar.  The pledge should not use its Implicit Trust Anchor
   database for validating the local domain registrar identity.  The
   pledge should send a voucher request message via the local domain
   registrar.  When the pledge downloads a voucher, it can validate the
   TLS connection to the local domain registrar and continue with
   enrollment and bootstrap as per standard BRSKI operation.

3.3.2.  Voucher Response

   The cloud registrar returned a voucher to the pledge.  The pledge
   should perform voucher verification as per standard BRSKI operation.
   The pledge should verify the voucher signature using the
   manufacturer-installed trust anchor(s), should verify the serial
   number in teh voucher, and must verify any nonce information in the
   voucher.

   The pledge should extract the "est-domain" field from the voucher,
   and should continue with EST enrollment as per standard BRSKI
   operation.

4.  Protocol Details

4.1.  Voucher Request Redirected to Local Domain Registrar

   This flow illlustrates the Owner Registrar Discovery flow.  A pledge
   is bootstrapping in a remote location with no local domain registrar.
   The assumption is that the owner registrar domain is accessible and
   the pledge can establish a network connection with the owner
   registrar.  This may require that the owner network firewall exposes
   the registrar on the public internet.







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   +--------+                                       +----------+
   | Pledge |                                       | Cloud RA |
   |        |                                       |          |
   +--------+                                       +----------+
       |                                                 |
       | 1. Mutual-authenticated TLS                     |
       |<----------------------------------------------->|
       |                                                 |
       | 2. Voucher Request                              |
       |------------------------------------------------>|
       |                                                 |
       | 3. 307 Location: owner-ra.example.com           |
       |<------------------------------------------------|
       |
       |                  +-----------+             +---------+
       |                  | Owner     |             |  MASA   |
       |                  | Registrar |             |         |
       |                  +-----------+             +---------+
       | 4. Provisional TLS   |                          |
       |<-------------------->|                          |
       |                      |                          |
       | 5. Voucher Request   |                          |
       |--------------------->| 6. Voucher Request       |
       |                      |------------------------->|
       |                      |                          |
       |                      | 7. Voucher Response      |
       |                      |<-------------------------|
       | 8. Voucher Response  |                          |
       |<---------------------|                          |
       |                      |                          |
       | 9. Validate TLS      |                          |
       |<-------------------->|                          |
       |                      |                          |
       | 10. etc.             |                          |
       |--------------------->|                          |

   The process starts, in step 1, when the Pledge establishes a Mutual
   TLS channel with the Cloud RA using artifacts created during the
   manufacturing process of the Pledge.

   In step 2, the Pledge sends a voucher request to the Cloud RA.

   The Cloud RA completes pledge ownership lookup as outlined in
   Section 3.2.1, and determines the owner registrar domain.  In step 3,
   the Cloud RA redirects the pledge to the owner registrar domain.






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   Steps 4 and onwards follow the standard BRSKI flow.  The pledge
   establishes a provisional TLS connection with the owner registrar,
   and sends a voucher request to the owner registrar.  The registar
   forwards the voucher request to the MASA.  Assuming the MASA issues a
   voucher, then the pledge validates the TLS connection with the
   registrar using the pinned-domain-cert from the voucher and completes
   the BRSKI flow.

4.2.  Voucher Request Handled by Cloud Registrar

   The Voucher includes the EST domain to use for EST enroll.  It is
   assumed services are accessed at that domain too.  As trust is
   already established via the Voucher, the pledge does a full TLS
   handshake against the local RA indicated by the voucher response.

   The returned voucher contains an attribute, "est-domain", defined in
   Section 5 below.  The pledge is directed to continue enrollment using
   the EST registrar found at that URI.  The pledge uses the pinned-
   domain-cert from the voucher to authenticate the EST registrar.
































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   +--------+                                       +----------+
   | Pledge |                                       | Cloud RA |
   |        |                                       | / MASA   |
   +--------+                                       +----------+
       |                                                 |
       | 1. Mutual TLS                                   |
       |<----------------------------------------------->|
       |                                                 |
       | 2. Voucher Request                              |
       |------------------------------------------------>|
       |                                                 |
       | 3. Voucher Response  {est-domain:fqdn}          |
       |<------------------------------------------------|
       |                                                 |
       |                 +----------+                    |
       |                 | RFC7030  |                    |
       |                 |  EST     |                    |
       |                 | Registrar|                    |
       |                 +----------+                    |
       |                      |                          |
       | 4. Full TLS          |                          |
       |<-------------------->|                          |
       |                                                 |
       |     3a. /voucher_status POST  success           |
       |------------------------------------------------>|
       |     ON FAILURE 3b. /voucher_status POST         |
       |                                                 |
       | 5. EST Enrol         |                          |
       |--------------------->|                          |
       |                      |                          |
       | 6. Certificate       |                          |
       |<---------------------|                          |
       |                      |                          |
       | 7. /enrollstatus     |                          |
       |--------------------->|                          |

   The process starts, in step 1, when the Pledge establishes a Mutual
   TLS channel with the Cloud RA/MASA using artifacts created during the
   manufacturing process of the Pledge.  In step 2, the Pledge sends a
   voucher request to the Cloud RA/MASA, and in response the Pledge
   receives an {{RFC8366} format voucher from the Cloud RA/MASA that
   includes its assigned EST domain in the est-domain attribute.

   At this stage, the Pledge should be able to establish a TLS channel
   with the EST Registrar.  The connection may involve crossing the
   Internet requiring a DNS lookup on the provided name.  It may also be
   a local address that includes an IP address literal including both
   [RFC1918] and IPv6 Unique Local Address.  The EST Registrar is



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   validated using the pinned-domain-cert value provided in the voucher
   as described in section 5.6.2 of
   [I-D.ietf-anima-bootstrapping-keyinfra].  This involves treating the
   artifact provided in the pinned-domain-cert as a trust anchor, and
   attempting to validate the EST Registrar from this anchor only.

   There is a case where the pinned-domain-cert is the identical End-
   Entity (EE) Certificate as the EST Registrar.  It also explicitly
   includes the case where the EST Registrar has a self-signed EE
   Certificate, but it may also be an EE certificate that is part of a
   larger PKI.  If the certificate is not a self-signed or EE
   certificate, then the Pledge SHOULD apply [RFC6125] DNS-ID validation
   on the certificate against the URL provided in the est-domain
   attribute.  If the est-domain was provided by with an IP address
   literal, then it is unlikely that it can be validated, and in that
   case, it is expected that either a self-signed certificate or an EE
   certificate will be pinned.

   The Pledge also has the details it needs to be able to create the CSR
   request to send to the RA based on the details provided in the
   voucher.

   In step 4, the Pledge establishes a TLS channel with the Cloud RA/
   MASA, and optionally the pledge should send a request, steps 3.a and
   3.b, to the Cloud RA/MASA to inform it that the Pledge was able to
   establish a secure TLS channel with the EST Registrar.

   The Pledge then follows that, in step 5, with an EST Enroll request
   with the CSR and obtains the requested certificate.  The Pledge must
   validate that the issued certificate has the expected identifier
   obtained from the Cloud RA/MASA in step 3.

5.  YANG extension for Voucher based redirect

   An extension to the [RFC8366] voucher is needed for the case where
   the client will be redirected to a local EST Registrar.

5.1.  YANG Tree













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   module: ietf-redirected-voucher

     grouping voucher-redirected-grouping
       +-- voucher
          +-- created-on                       yang:date-and-time
          +-- expires-on?                      yang:date-and-time
          +-- assertion                        enumeration
          +-- serial-number                    string
          +-- idevid-issuer?                   binary
          +-- pinned-domain-cert               binary
          +-- domain-cert-revocation-checks?   boolean
          +-- nonce?                           binary
          +-- last-renewal-date?               yang:date-and-time
          +-- est-domain?                      ietf:uri
          +-- additional-configuration?        ietf:uri

5.2.  YANG Voucher

   <CODE BEGINS> file "ietf-redirected-voucher@2020-09-23.yang"
   module ietf-redirected-voucher {
     yang-version 1.1;

     namespace
       "urn:ietf:params:xml:ns:yang:ietf-redirected-voucher";
     prefix "redirected";

     import ietf-restconf {
       prefix rc;
       description
         "This import statement is only present to access
          the yang-data extension defined in RFC 8040.";
       reference "RFC 8040: RESTCONF Protocol";
     }

     import ietf-inet-types {
       prefix ietf;
       reference "RFC 6991: Common YANG Data Types";
     }

     import ietf-voucher {
       prefix "v";
     }

     organization
      "IETF ANIMA Working Group";

     contact
      "WG Web:   <http://tools.ietf.org/wg/anima/>



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       WG List:  <mailto:anima@ietf.org>
       Author:   Michael Richardson
                 <mailto:mcr+ietf@sandelman.ca>
       Author:   Owen Friel
                 <mailto: ofriel@cisco.com>
       Author:   Rifaat Shekh-Yusef
                 <mailto: rifaat.ietf@gmail.com>";
   description
     "This module extendes the base RFC8366 voucher format to include a redirect
      to an EST server to which enrollment should continue.

      The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
      'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'MAY',
      and 'OPTIONAL' in the module text are to be interpreted as
      described in BCP14, RFC 2119, and RFC8174.";

     revision "2020-09-23" {
       description
        "Initial version";
       reference
        "RFC XXXX: Voucher Profile for Cloud redirected Devices";
     }

     rc:yang-data voucher-redirected-artifact {
       // YANG data template for a voucher.
       uses voucher-redirected-grouping;
     }

     // Grouping defined for future usage
     grouping voucher-redirected-grouping {
       description
         "Grouping to allow reuse/extensions in future work.";

       uses v:voucher-artifact-grouping {

         augment "voucher" {
           description "Base the constrained voucher
                        upon the regular one";
           leaf est-domain {
             type ietf:uri;
             description
               "The est-domain is a URL to which the Pledge should continue
                doing enrollment rather than with the Cloud Registrar.";
           }
           leaf additional-configuration {
             type ietf:uri;
             description
               "The additional-configuration attribute contains a URL to which the Pledge can retrieve additional configuration



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                information. The contents of this URL are vendor specific.  This is intended to do things like configure
                a VoIP phone to point to the correct hosted PBX, for example.";
           }
         }
       }
     }
   }
   <CODE ENDS>

6.  IANA Considerations

   TODO:MCR - Will need to add IETF YANG registration from templates. [[
   TODO ]]

7.  Security Considerations

   [[ TODO ]]

8.  References

8.1.  Normative References

   [I-D.ietf-anima-bootstrapping-keyinfra]
              Pritikin, M., Richardson, M., Eckert, T., Behringer, M.,
              and K. Watsen, "Bootstrapping Remote Secure Key
              Infrastructures (BRSKI)", Work in Progress, Internet-
              Draft, draft-ietf-anima-bootstrapping-keyinfra-44, 21
              September 2020, <http://www.ietf.org/internet-drafts/
              draft-ietf-anima-bootstrapping-keyinfra-44.txt>.

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

   [RFC7030]  Pritikin, M., Ed., Yee, P., Ed., and D. Harkins, Ed.,
              "Enrollment over Secure Transport", RFC 7030,
              DOI 10.17487/RFC7030, October 2013,
              <https://www.rfc-editor.org/info/rfc7030>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8366]  Watsen, K., Richardson, M., Pritikin, M., and T. Eckert,
              "A Voucher Artifact for Bootstrapping Protocols",
              RFC 8366, DOI 10.17487/RFC8366, May 2018,
              <https://www.rfc-editor.org/info/rfc8366>.



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8.2.  Informative References

   [IEEE802.1AR]
              IEEE Standard, ., "IEEE 802.1AR Secure Device Identifier",
              2018, <http://standards.ieee.org/findstds/
              standard/802.1AR-2018.html>.

   [RFC1918]  Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G.
              J., and E. Lear, "Address Allocation for Private
              Internets", BCP 5, RFC 1918, DOI 10.17487/RFC1918,
              February 1996, <https://www.rfc-editor.org/info/rfc1918>.

   [RFC6125]  Saint-Andre, P. and J. Hodges, "Representation and
              Verification of Domain-Based Application Service Identity
              within Internet Public Key Infrastructure Using X.509
              (PKIX) Certificates in the Context of Transport Layer
              Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
              2011, <https://www.rfc-editor.org/info/rfc6125>.

   [RFC7250]  Wouters, P., Ed., Tschofenig, H., Ed., Gilmore, J.,
              Weiler, S., and T. Kivinen, "Using Raw Public Keys in
              Transport Layer Security (TLS) and Datagram Transport
              Layer Security (DTLS)", RFC 7250, DOI 10.17487/RFC7250,
              June 2014, <https://www.rfc-editor.org/info/rfc7250>.

   [RFC8572]  Watsen, K., Farrer, I., and M. Abrahamsson, "Secure Zero
              Touch Provisioning (SZTP)", RFC 8572,
              DOI 10.17487/RFC8572, April 2019,
              <https://www.rfc-editor.org/info/rfc8572>.

Authors' Addresses

   Owen Friel
   Cisco

   Email: ofriel@cisco.com


   Rifaat Shekh-Yusef
   Auth0

   Email: rifaat.s.ietf@gmail.com


   Michael Richardson
   Sandelman Software Works

   Email: mcr+ietf@sandelman.ca



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