draft-ietf-anima-bootstrapping-keyinfra-13.txt   draft-ietf-anima-bootstrapping-keyinfra-14.txt 
ANIMA WG M. Pritikin ANIMA WG M. Pritikin
Internet-Draft Cisco Internet-Draft Cisco
Intended status: Standards Track M. Richardson Intended status: Standards Track M. Richardson
Expires: September 27, 2018 Sandelman Expires: October 15, 2018 Sandelman
M. Behringer M. Behringer
S. Bjarnason S. Bjarnason
Arbor Networks Arbor Networks
K. Watsen K. Watsen
Juniper Networks Juniper Networks
March 26, 2018 April 13, 2018
Bootstrapping Remote Secure Key Infrastructures (BRSKI) Bootstrapping Remote Secure Key Infrastructures (BRSKI)
draft-ietf-anima-bootstrapping-keyinfra-13 draft-ietf-anima-bootstrapping-keyinfra-14
Abstract Abstract
This document specifies automated bootstrapping of a remote secure This document specifies automated bootstrapping of a remote secure
key infrastructure (BRSKI) using manufacturer installed X.509 key infrastructure (BRSKI) using manufacturer installed X.509
certificate, in combination with a manufacturer's authorizing certificate, in combination with a manufacturer's authorizing
service, both online and offline. Bootstrapping a new device can service, both online and offline. Bootstrapping a new device can
occur using a routable address and a cloud service, or using only occur using a routable address and a cloud service, or using only
link-local connectivity, or on limited/disconnected networks. link-local connectivity, or on limited/disconnected networks.
Support for lower security models, including devices with minimal Support for lower security models, including devices with minimal
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 27, 2018. This Internet-Draft will expire on October 15, 2018.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Prior Bootstrapping Approaches . . . . . . . . . . . . . 5 1.1. Prior Bootstrapping Approaches . . . . . . . . . . . . . 5
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 6 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 6
1.3. Scope of solution . . . . . . . . . . . . . . . . . . . . 9 1.3. Scope of solution . . . . . . . . . . . . . . . . . . . . 9
1.3.1. Support environment . . . . . . . . . . . . . . . . . 9 1.3.1. Support environment . . . . . . . . . . . . . . . . . 9
1.3.2. Constrained environments . . . . . . . . . . . . . . 10 1.3.2. Constrained environments . . . . . . . . . . . . . . 10
1.3.3. Network Access Controls . . . . . . . . . . . . . . . 10 1.3.3. Network Access Controls . . . . . . . . . . . . . . . 11
1.4. Leveraging the new key infrastructure / next steps . . . 11 1.4. Leveraging the new key infrastructure / next steps . . . 11
1.5. Requirements for Autonomic Network Infrastructure (ANI) 1.5. Requirements for Autonomic Network Infrastructure (ANI)
devices . . . . . . . . . . . . . . . . . . . . . . . . . 11 devices . . . . . . . . . . . . . . . . . . . . . . . . . 11
2. Architectural Overview . . . . . . . . . . . . . . . . . . . 12 2. Architectural Overview . . . . . . . . . . . . . . . . . . . 12
2.1. Behavior of a Pledge . . . . . . . . . . . . . . . . . . 13 2.1. Behavior of a Pledge . . . . . . . . . . . . . . . . . . 14
2.2. Secure Imprinting using Vouchers . . . . . . . . . . . . 15 2.2. Secure Imprinting using Vouchers . . . . . . . . . . . . 15
2.3. Initial Device Identifier . . . . . . . . . . . . . . . . 16 2.3. Initial Device Identifier . . . . . . . . . . . . . . . . 16
2.3.1. Identification of the Pledge . . . . . . . . . . . . 16 2.3.1. Identification of the Pledge . . . . . . . . . . . . 16
2.3.2. MASA URI extension . . . . . . . . . . . . . . . . . 17 2.3.2. MASA URI extension . . . . . . . . . . . . . . . . . 17
2.4. Protocol Flow . . . . . . . . . . . . . . . . . . . . . . 18 2.4. Protocol Flow . . . . . . . . . . . . . . . . . . . . . . 18
2.5. Architectural Components . . . . . . . . . . . . . . . . 20 2.5. Architectural Components . . . . . . . . . . . . . . . . 20
2.5.1. Pledge . . . . . . . . . . . . . . . . . . . . . . . 20 2.5.1. Pledge . . . . . . . . . . . . . . . . . . . . . . . 20
2.5.2. Circuit Proxy . . . . . . . . . . . . . . . . . . . . 20 2.5.2. Join Proxy . . . . . . . . . . . . . . . . . . . . . 20
2.5.3. Domain Registrar . . . . . . . . . . . . . . . . . . 20 2.5.3. Domain Registrar . . . . . . . . . . . . . . . . . . 20
2.5.4. Manufacturer Service . . . . . . . . . . . . . . . . 20 2.5.4. Manufacturer Service . . . . . . . . . . . . . . . . 20
2.5.5. Public Key Infrastructure (PKI) . . . . . . . . . . . 20 2.5.5. Public Key Infrastructure (PKI) . . . . . . . . . . . 20
2.6. Certificate Time Validation . . . . . . . . . . . . . . . 21 2.6. Certificate Time Validation . . . . . . . . . . . . . . . 21
2.6.1. Lack of realtime clock . . . . . . . . . . . . . . . 21 2.6.1. Lack of realtime clock . . . . . . . . . . . . . . . 21
2.6.2. Infinite Lifetime of IDevID . . . . . . . . . . . . . 23 2.6.2. Infinite Lifetime of IDevID . . . . . . . . . . . . . 23
2.7. Cloud Registrar . . . . . . . . . . . . . . . . . . . . . 23 2.7. Cloud Registrar . . . . . . . . . . . . . . . . . . . . . 23
2.8. Determining the MASA to contact . . . . . . . . . . . . . 23 2.8. Determining the MASA to contact . . . . . . . . . . . . . 23
3. Voucher-Request artifact . . . . . . . . . . . . . . . . . . 24 3. Voucher-Request artifact . . . . . . . . . . . . . . . . . . 24
3.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 25 3.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 25
3.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . 25 3.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . 25
3.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 27 3.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 27
4. Proxying details (Pledge - Proxy - Registrar) . . . . . . . . 30 4. Proxying details (Pledge - Proxy - Registrar) . . . . . . . . 30
4.1. Pledge discovery of Proxy . . . . . . . . . . . . . . . . 31 4.1. Pledge discovery of Proxy . . . . . . . . . . . . . . . . 31
4.1.1. Proxy GRASP announcements . . . . . . . . . . . . . . 32 4.1.1. Proxy GRASP announcements . . . . . . . . . . . . . . 32
4.2. CoAP connection to Registrar . . . . . . . . . . . . . . 33 4.2. CoAP connection to Registrar . . . . . . . . . . . . . . 33
4.3. Proxy discovery of Registrar . . . . . . . . . . . . . . 33 4.3. Proxy discovery of Registrar . . . . . . . . . . . . . . 33
5. Protocol Details (Pledge - Registrar - MASA) . . . . . . . . 35 5. Protocol Details (Pledge - Registrar - MASA) . . . . . . . . 35
5.1. BRSKI-EST TLS establishment details . . . . . . . . . . . 37 5.1. BRSKI-EST TLS establishment details . . . . . . . . . . . 36
5.2. Pledge Requests Voucher from the Registrar . . . . . . . 37 5.2. Pledge Requests Voucher from the Registrar . . . . . . . 37
5.3. BRSKI-MASA TLS establishment details . . . . . . . . . . 39 5.3. BRSKI-MASA TLS establishment details . . . . . . . . . . 38
5.4. Registrar Requests Voucher from MASA . . . . . . . . . . 39 5.4. Registrar Requests Voucher from MASA . . . . . . . . . . 39
5.4.1. Renew for expired voucher . . . . . . . . . . . . . . 41 5.4.1. MASA renewal of expired vouchers . . . . . . . . . . 40
5.4.2. Voucher signature consistency . . . . . . . . . . . . 41 5.4.2. MASA verification of voucher-request signature
5.4.3. Registrar revocation consistency . . . . . . . . . . 41 consistency . . . . . . . . . . . . . . . . . . . . . 40
5.4.4. Pledge proximity assertion . . . . . . . . . . . . . 42 5.4.3. MASA authentication of registrar (certificate) . . . 41
5.4.5. Registar (certificate) authentication . . . . . . . . 42 5.4.4. MASA revocation checking of registrar (certificate) . 41
5.4.6. Registrar Anchor . . . . . . . . . . . . . . . . . . 42 5.4.5. MASA verification of pledge prior-signed-voucher-
5.5. Voucher Response . . . . . . . . . . . . . . . . . . . . 42 request . . . . . . . . . . . . . . . . . . . . . . . 42
5.5.1. Completing authentication of Provisional TLS 5.4.6. MASA pinning of registrar . . . . . . . . . . . . . . 42
connection . . . . . . . . . . . . . . . . . . . . . 44 5.4.7. MASA nonce handling . . . . . . . . . . . . . . . . . 42
5.6. Voucher Status Telemetry . . . . . . . . . . . . . . . . 45 5.5. MASA Voucher Response . . . . . . . . . . . . . . . . . . 42
5.7. MASA authorization log Request . . . . . . . . . . . . . 45 5.5.1. Pledge voucher verification . . . . . . . . . . . . . 44
5.7.1. MASA authorization log Response . . . . . . . . . . . 46 5.5.2. Pledge authentication of provisional TLS connection . 44
5.8. EST Integration for PKI bootstrapping . . . . . . . . . . 48 5.6. Pledge Voucher Status Telemetry . . . . . . . . . . . . . 45
5.8.1. EST Distribution of CA Certificates . . . . . . . . . 48 5.7. Registrar audit log request . . . . . . . . . . . . . . . 46
5.8.2. EST CSR Attributes . . . . . . . . . . . . . . . . . 49 5.7.1. MASA audit log response . . . . . . . . . . . . . . . 47
5.8.3. EST Client Certificate Request . . . . . . . . . . . 50 5.7.2. Registrar audit log verification . . . . . . . . . . 49
5.8.4. Enrollment Status Telemetry . . . . . . . . . . . . . 50 5.8. EST Integration for PKI bootstrapping . . . . . . . . . . 50
5.8.5. Multiple certificates . . . . . . . . . . . . . . . . 51 5.8.1. EST Distribution of CA Certificates . . . . . . . . . 50
5.8.6. EST over CoAP . . . . . . . . . . . . . . . . . . . . 51 5.8.2. EST CSR Attributes . . . . . . . . . . . . . . . . . 51
6. Reduced security operational modes . . . . . . . . . . . . . 51 5.8.3. EST Client Certificate Request . . . . . . . . . . . 52
6.1. Trust Model . . . . . . . . . . . . . . . . . . . . . . . 51 5.8.4. Enrollment Status Telemetry . . . . . . . . . . . . . 52
6.2. Pledge security reductions . . . . . . . . . . . . . . . 52 5.8.5. Multiple certificates . . . . . . . . . . . . . . . . 53
6.3. Registrar security reductions . . . . . . . . . . . . . . 53 5.8.6. EST over CoAP . . . . . . . . . . . . . . . . . . . . 53
6.4. MASA security reductions . . . . . . . . . . . . . . . . 54 6. Reduced security operational modes . . . . . . . . . . . . . 53
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 54 6.1. Trust Model . . . . . . . . . . . . . . . . . . . . . . . 53
7.1. Well-known EST registration . . . . . . . . . . . . . . . 54 6.2. Pledge security reductions . . . . . . . . . . . . . . . 54
7.2. PKIX Registry . . . . . . . . . . . . . . . . . . . . . . 55 6.3. Registrar security reductions . . . . . . . . . . . . . . 55
7.3. Voucher Status Telemetry . . . . . . . . . . . . . . . . 55 6.4. MASA security reductions . . . . . . . . . . . . . . . . 56
8. Privacy Considerations . . . . . . . . . . . . . . . . . . . 55 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 56
8.1. MASA authorization log . . . . . . . . . . . . . . . . . 55 7.1. Well-known EST registration . . . . . . . . . . . . . . . 56
9. Security Considerations . . . . . . . . . . . . . . . . . . . 56 7.2. PKIX Registry . . . . . . . . . . . . . . . . . . . . . . 57
9.1. Freshness in Voucher-Requests . . . . . . . . . . . . . . 57 7.3. Voucher Status Telemetry . . . . . . . . . . . . . . . . 57
9.2. Trusting manufacturers . . . . . . . . . . . . . . . . . 58 7.4. DNS Service Names . . . . . . . . . . . . . . . . . . . . 57
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 59 7.5. MUD File Extension for the MASA server . . . . . . . . . 58
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 59 8. Privacy Considerations . . . . . . . . . . . . . . . . . . . 58
11.1. Normative References . . . . . . . . . . . . . . . . . . 60 8.1. MASA audit log . . . . . . . . . . . . . . . . . . . . . 58
11.2. Informative References . . . . . . . . . . . . . . . . . 62 9. Security Considerations . . . . . . . . . . . . . . . . . . . 58
9.1. Freshness in Voucher-Requests . . . . . . . . . . . . . . 60
Appendix A. IPv4 and non-ANI operations . . . . . . . . . . . . 64 9.2. Trusting manufacturers . . . . . . . . . . . . . . . . . 61
A.1. IPv4 Link Local addresses . . . . . . . . . . . . . . . . 64 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 62
A.2. Use of DHCPv4 . . . . . . . . . . . . . . . . . . . . . . 64 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 62
Appendix B. mDNS / DNSSD proxy discovery options . . . . . . . . 65 11.1. Normative References . . . . . . . . . . . . . . . . . . 62
Appendix C. IPIP Join Proxy mechanism . . . . . . . . . . . . . 65 11.2. Informative References . . . . . . . . . . . . . . . . . 65
C.1. Multiple Join networks on the Join Proxy side . . . . . . 66 Appendix A. IPv4 and non-ANI operations . . . . . . . . . . . . 67
C.2. Automatic configuration of tunnels on Registrar . . . . . 67 A.1. IPv4 Link Local addresses . . . . . . . . . . . . . . . . 67
C.3. Proxy Neighbor Discovery by Join Proxy . . . . . . . . . 67 A.2. Use of DHCPv4 . . . . . . . . . . . . . . . . . . . . . . 67
Appendix B. mDNS / DNSSD proxy discovery options . . . . . . . . 67
Appendix C. IPIP Join Proxy mechanism . . . . . . . . . . . . . 68
C.1. Multiple Join networks on the Join Proxy side . . . . . . 69
C.2. Automatic configuration of tunnels on Registrar . . . . . 69
C.3. Proxy Neighbor Discovery by Join Proxy . . . . . . . . . 69
C.4. Use of connected sockets; or IP_PKTINFO for CoAP on C.4. Use of connected sockets; or IP_PKTINFO for CoAP on
Registrar . . . . . . . . . . . . . . . . . . . . . . . . 67 Registrar . . . . . . . . . . . . . . . . . . . . . . . . 70
C.5. Use of socket extension rather than virtual interface . . 68 C.5. Use of socket extension rather than virtual interface . . 70
Appendix D. MUD Extension . . . . . . . . . . . . . . . . . . . 68 Appendix D. MUD Extension . . . . . . . . . . . . . . . . . . . 71
Appendix E. Example Vouchers . . . . . . . . . . . . . . . . . . 70 Appendix E. Example Vouchers . . . . . . . . . . . . . . . . . . 73
E.1. Keys involved . . . . . . . . . . . . . . . . . . . . . . 70 E.1. Keys involved . . . . . . . . . . . . . . . . . . . . . . 73
E.1.1. MASA key pair for voucher signatures . . . . . . . . 70 E.1.1. MASA key pair for voucher signatures . . . . . . . . 73
E.1.2. Manufacturer key pair for IDevID signatures . . . . . 70 E.1.2. Manufacturer key pair for IDevID signatures . . . . . 73
E.1.3. Registrar key pair . . . . . . . . . . . . . . . . . 71 E.1.3. Registrar key pair . . . . . . . . . . . . . . . . . 74
E.1.4. Pledge key pair . . . . . . . . . . . . . . . . . . . 73 E.1.4. Pledge key pair . . . . . . . . . . . . . . . . . . . 76
E.2. Example process . . . . . . . . . . . . . . . . . . . . . 74 E.2. Example process . . . . . . . . . . . . . . . . . . . . . 77
E.2.1. Pledge to Registrar . . . . . . . . . . . . . . . . . 74 E.2.1. Pledge to Registrar . . . . . . . . . . . . . . . . . 77
E.2.2. Registrar to MASA . . . . . . . . . . . . . . . . . . 80 E.2.2. Registrar to MASA . . . . . . . . . . . . . . . . . . 83
E.2.3. MASA to Registrar . . . . . . . . . . . . . . . . . . 86 E.2.3. MASA to Registrar . . . . . . . . . . . . . . . . . . 89
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 91 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 94
1. Introduction 1. Introduction
BRSKI provides a solution for secure zero-touch (automated) bootstrap BRSKI provides a solution for secure zero-touch (automated) bootstrap
of virgin (untouched) devices that are called Pledges in this of virgin (untouched) devices that are called pledges in this
document. These Pledges need to discover (or be discovered by) an document. These pledges need to discover (or be discovered by) an
element of the network domain to which the Pledge belongs to perform element of the network domain to which the pledge belongs to perform
the bootstrap. This element (device) is called the Registrar. the bootstrap. This element (device) is called the registrar.
Before any other operation, Pledge and Registrar need to establish Before any other operation, pledge and registrar need to establish
mutual trust: mutual trust:
1. Registrar authenticating the Pledge: "Who is this device? What 1. Registrar authenticating the pledge: "Who is this device? What
is its identity?" is its identity?"
2. Registrar authorizing the Pledge: "Is it mine? Do I want it? 2. Registrar authorizing the pledge: "Is it mine? Do I want it?
What are the chances it has been compromised?" What are the chances it has been compromised?"
3. Pledge authenticating the Registrar/Domain: "What is this 3. Pledge authenticating the registrar: "What is this registrar's
domain's identity?" identity?"
4. Pledge authorizing the Registrar: "Should I join it?" 4. Pledge authorizing the registrar: "Should I join it?"
This document details protocols and messages to answer the above This document details protocols and messages to answer the above
questions. It uses a TLS connection and an PKIX (X.509v3) questions. It uses a TLS connection and an PKIX (X.509v3)
certificate (an IEEE 802.1AR [IDevID] LDevID) of the Pledge to answer certificate (an IEEE 802.1AR [IDevID] LDevID) of the pledge to answer
points 1 and 2. It uses a new artifact called a "voucher" that the points 1 and 2. It uses a new artifact called a "voucher" that the
registrar receives from a "Manufacturer Authorized Signing Authority" registrar receives from a "Manufacturer Authorized Signing Authority"
and passes to the Pledge to answer points 3 and 2. and passes to the pledge to answer points 3 and 2.
A proxy provides very limited connectivity between the pledge and the A proxy provides very limited connectivity between the pledge and the
Registrar. registrar.
The syntactic details of vouchers are described in detail in The syntactic details of vouchers are described in detail in
[I-D.ietf-anima-voucher]. This document details automated protocol [I-D.ietf-anima-voucher]. This document details automated protocol
mechanisms to obtain vouchers, including the definition of a mechanisms to obtain vouchers, including the definition of a
'voucher-request' message that is a minor extension to the voucher 'voucher-request' message that is a minor extension to the voucher
format (see Section 3) defined by [I-D.ietf-anima-voucher]. format (see Section 3) defined by [I-D.ietf-anima-voucher].
BRSKI results in the Pledge storing an X.509 root certificate BRSKI results in the pledge storing an X.509 root certificate
sufficient for verifying the Registrar identity. In the process a sufficient for verifying the registrar identity. In the process a
TLS connection is established that can be directly used for TLS connection is established that can be directly used for
Enrollment over Secure Transport (EST). In effect BRSKI provides an Enrollment over Secure Transport (EST). In effect BRSKI provides an
automated mechanism for the "Bootstrap Distribution of CA automated mechanism for the "Bootstrap Distribution of CA
Certificates" described in [RFC7030] Section 4.1.1 wherein the Pledge Certificates" described in [RFC7030] Section 4.1.1 wherein the pledge
"MUST [...] engage a human user to authorize the CA certificate using "MUST [...] engage a human user to authorize the CA certificate using
out-of-band" information". With BRSKI the Pledge now can automate out-of-band" information". With BRSKI the pledge now can automate
this process using the voucher. Integration with a complete EST this process using the voucher. Integration with a complete EST
enrollment is optional but trivial. enrollment is optional but trivial.
BRSKI is agile enough to support bootstrapping alternative key BRSKI is agile enough to support bootstrapping alternative key
infrastructures, such as a symmetric key solutions, but no such infrastructures, such as a symmetric key solutions, but no such
system is described in this document. system is described in this document.
1.1. Prior Bootstrapping Approaches 1.1. Prior Bootstrapping Approaches
To literally "pull yourself up by the bootstraps" is an impossible To literally "pull yourself up by the bootstraps" is an impossible
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o using a configured Explicit TA database (not an autonomic solution o using a configured Explicit TA database (not an autonomic solution
because the distribution of an explicit TA database is not because the distribution of an explicit TA database is not
autonomic), autonomic),
o and using a Certificate-Less TLS mutual authentication method (not o and using a Certificate-Less TLS mutual authentication method (not
an autonomic solution because the distribution of symmetric key an autonomic solution because the distribution of symmetric key
material is not autonomic). material is not autonomic).
These "touch" methods do not meet the requirements for zero-touch. These "touch" methods do not meet the requirements for zero-touch.
There are "call home" technologies where the Pledge first establishes There are "call home" technologies where the pledge first establishes
a connection to a well known manufacturer service using a common a connection to a well known manufacturer service using a common
client-server authentication model. After mutual authentication, client-server authentication model. After mutual authentication,
appropriate credentials to authenticate the target domain are appropriate credentials to authenticate the target domain are
transfered to the Pledge. This creates serveral problems and transfered to the pledge. This creates serveral problems and
limitations: limitations:
o the Pledge requires realtime connectivity to the manufacturer o the pledge requires realtime connectivity to the manufacturer
service, service,
o the domain identity is exposed to the manufacturer service (this o the domain identity is exposed to the manufacturer service (this
is a privacy concern), is a privacy concern),
o the manufacturer is responsible for making the authorization o the manufacturer is responsible for making the authorization
decisions (this is a liability concern), decisions (this is a liability concern),
BRSKI addresses these issues by defining extensions to the EST BRSKI addresses these issues by defining extensions to the EST
protocol for the automated distribution of vouchers. protocol for the automated distribution of vouchers.
skipping to change at page 6, line 52 skipping to change at page 7, line 8
1.2. Terminology 1.2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in "OPTIONAL" in this document are to be interpreted as described in
[RFC2119]. [RFC2119].
The following terms are defined for clarity: The following terms are defined for clarity:
domainID: The domain IDentity is the 160-bit SHA-1 hash of the BIT domainID: The domain IDentity is the 160-bit SHA-1 hash of the BIT
STRING of the subjectPublicKey of the root certificate for the STRING of the subjectPublicKey of the pinned-domain-cert leaf,
Registrars in the domain. This is consistent with the subject key i.e. the Registrars' certificate. This is consistent with the
identifier (Section 4.2.1.2 [RFC5280]). subject key identifier (Section 4.2.1.2 [RFC5280]).
drop ship: The physical distribution of equipment containing the drop ship: The physical distribution of equipment containing the
"factory default" configuration to a final destination. In zero- "factory default" configuration to a final destination. In zero-
touch scenarios there is no staging or pre-configuration during touch scenarios there is no staging or pre-configuration during
drop-ship. drop-ship.
imprint: The process where a device obtains the cryptographic key imprint: The process where a device obtains the cryptographic key
material to identify and trust future interactions with a network. material to identify and trust future interactions with a network.
This term is taken from Konrad Lorenz's work in biology with new This term is taken from Konrad Lorenz's work in biology with new
ducklings: during a critical period, the duckling would assume ducklings: during a critical period, the duckling would assume
skipping to change at page 7, line 32 skipping to change at page 7, line 37
Lorenz's work was first noted in [Stajano99theresurrecting]. Lorenz's work was first noted in [Stajano99theresurrecting].
enrollment: The process where a device presents key material to a enrollment: The process where a device presents key material to a
network and acquires a network specific identity. For example network and acquires a network specific identity. For example
when a certificate signing request is presented to a certification when a certificate signing request is presented to a certification
authority and a certificate is obtained in response. authority and a certificate is obtained in response.
Pledge: The prospective device, which has an identity installed at Pledge: The prospective device, which has an identity installed at
the factory. the factory.
Voucher: A signed artifact from the MASA that indicates to a Pledge Voucher: A signed artifact from the MASA that indicates to a pledge
the cryptographic identity of the Registrar it should trust. the cryptographic identity of the registrar it should trust.
There are different types of vouchers depending on how that trust There are different types of vouchers depending on how that trust
is asserted. Multiple voucher types are defined in is asserted. Multiple voucher types are defined in
[I-D.ietf-anima-voucher] [I-D.ietf-anima-voucher]
Domain: The set of entities that share a common local trust anchor. Domain: The set of entities that share a common local trust anchor.
This includes the Proxy, Registrar, Domain Certificate Authority, This includes the proxy, registrar, Domain Certificate Authority,
Management components and any existing entity that is already a Management components and any existing entity that is already a
member of the domain. member of the domain.
Domain CA: The domain Certification Authority (CA) provides Domain CA: The domain Certification Authority (CA) provides
certification functionalities to the domain. At a minimum it certification functionalities to the domain. At a minimum it
provides certification functionalities to a Registrar and manages provides certification functionalities to a registrar and manages
the private key that defines the domain. Optionally, it certifies the private key that defines the domain. Optionally, it certifies
all elements. all elements.
Join Registrar (and Coordinator): A representative of the domain Join Registrar (and Coordinator): A representative of the domain
that is configured, perhaps autonomically, to decide whether a new that is configured, perhaps autonomically, to decide whether a new
device is allowed to join the domain. The administrator of the device is allowed to join the domain. The administrator of the
domain interfaces with a Join Registrar (and Coordinator) to domain interfaces with a "join registrar (and coordinator)" to
control this process. Typically a Join Registrar is "inside" its control this process. Typically a join registrar is "inside" its
domain. For simplicity this document often refers to this as just domain. For simplicity this document often refers to this as just
"Registrar". Within [I-D.ietf-anima-reference-model] this is "registrar". Within [I-D.ietf-anima-reference-model] this is
refered to as the Join Registrar Autonomic Service Agent. refered to as the "join registrar autonomic service agent". Other
communities use the abbreviation "JRC".
(Public) Key Infrastructure: The collection of systems and processes (Public) Key Infrastructure: The collection of systems and processes
that sustain the activities of a public key system. The Join that sustain the activities of a public key system. The registrar
Registrar (and Coordinator) acts as an [RFC5280] and [RFC5272] acts as an [RFC5280] and [RFC5272] (see section 7) "Registration
(see section 7) "Registration Authority". Authority".
Join Proxy: A domain entity that helps the Pledge join the domain. Join Proxy: A domain entity that helps the pledge join the domain.
A Proxy facilitates communication for devices that find themselves A join proxy facilitates communication for devices that find
in an environment where they are not provided connectivity until themselves in an environment where they are not provided
after they are validated as members of the domain. The Pledge is connectivity until after they are validated as members of the
unaware that they are communicating with a Proxy rather than domain. For simplicity this document sometimes uses the term of
directly with a Registrar. 'proxy' to indicate the join proxy. The pledge is unaware that
they are communicating with a proxy rather than directly with a
registrar.
Circuit Proxy: A stateful implementation of the join proxy. This is
the assumed type of proxy.
IPIP Proxy: A stateless proxy alternative.
MASA Service: A third-party Manufacturer Authorized Signing MASA Service: A third-party Manufacturer Authorized Signing
Authority (MASA) service on the global Internet. The MASA signs Authority (MASA) service on the global Internet. The MASA signs
vouchers. It also provides a repository for audit log information vouchers. It also provides a repository for audit log information
of privacy protected bootstrapping events. It does not track of privacy protected bootstrapping events. It does not track
ownership. ownership.
Ownership Tracker: An Ownership Tracker service on the global Ownership Tracker: An Ownership Tracker service on the global
internet. The Ownership Tracker uses business processes to internet. The Ownership Tracker uses business processes to
accurately track ownership of all devices shipped against domains accurately track ownership of all devices shipped against domains
that have purchased them. Although optional, this component that have purchased them. Although optional, this component
allows vendors to provide additional value in cases where their allows vendors to provide additional value in cases where their
sales and distribution channels allow for accurately tracking of sales and distribution channels allow for accurately tracking of
such ownership. Ownership tracking information is indicated in such ownership. Ownership tracking information is indicated in
vouchers as described in [I-D.ietf-anima-voucher] vouchers as described in [I-D.ietf-anima-voucher]
IDevID: An Initial Device Identity X.509 certificate installed by IDevID: An Initial Device Identity X.509 certificate installed by
the vendor on new equipment. the vendor on new equipment.
TOFU: Trust on First Use. Used similarly to [RFC7435]. This is TOFU: Trust on First Use. Used similarly to [RFC7435]. This is
where a Pledge device makes no security decisions but rather where a pledge device makes no security decisions but rather
simply trusts the first Registrar it is contacted by. This is simply trusts the first registrar it is contacted by. This is
also known as the "resurrecting duckling" model. also known as the "resurrecting duckling" model.
nonced: a voucher (or request) that contains a nonce (the normal nonced: a voucher (or request) that contains a nonce (the normal
case). case).
nonceless: a voucher (or request) that does not contain a nonce, nonceless: a voucher (or request) that does not contain a nonce,
relying upon accurate clocks for expiration, or which does not relying upon accurate clocks for expiration, or which does not
expire. expire.
manufacturer: the term manufacturer is used throughout this document manufacturer: the term manufacturer is used throughout this document
skipping to change at page 9, line 22 skipping to change at page 9, line 34
uniform firmware load, to be shipped directly to all customers. uniform firmware load, to be shipped directly to all customers.
This eliminates costs for the manufacturer. This also reduces the This eliminates costs for the manufacturer. This also reduces the
number of products supported in the field increasing the chance number of products supported in the field increasing the chance
that firmware will be more up to date. that firmware will be more up to date.
ANI: The Autonomic Network Infrastructure as defined by ANI: The Autonomic Network Infrastructure as defined by
[I-D.ietf-anima-autonomic-control-plane]. This document details [I-D.ietf-anima-autonomic-control-plane]. This document details
specific requirements for pledges, proxies and registrars when specific requirements for pledges, proxies and registrars when
they are part of an ANI. they are part of an ANI.
offline: When an architectural component cannot perform realtime
communications with a peer, either due to network connectivity or
because the peer is turned off, the operation is said to be
occurring offline.
1.3. Scope of solution 1.3. Scope of solution
1.3.1. Support environment 1.3.1. Support environment
This solution (BRSKI) can support large router platforms with multi- This solution (BRSKI) can support large router platforms with multi-
gigabit inter-connections, mounted in controlled access data centers. gigabit inter-connections, mounted in controlled access data centers.
But this solution is not exclusive to large equipment: it is intended But this solution is not exclusive to large equipment: it is intended
to scale to thousands of devices located in hostile environments, to scale to thousands of devices located in hostile environments,
such as ISP provided CPE devices which are drop-shipped to the end such as ISP provided CPE devices which are drop-shipped to the end
user. The situation where an order is fulfilled from distributed user. The situation where an order is fulfilled from distributed
warehouse from a common stock and shipped directly to the target warehouse from a common stock and shipped directly to the target
location at the request of a domain owner is explicitly supported. location at the request of a domain owner is explicitly supported.
That stock ("SKU") could be provided to a number of potential domain That stock ("SKU") could be provided to a number of potential domain
owners, and the eventual domain owner will not know a-priori which owners, and the eventual domain owner will not know a-priori which
device will go to which location. device will go to which location.
The bootstrapping process can take minutes to complete depending on The bootstrapping process can take minutes to complete depending on
the network infrastructure and device processing speed. The network the network infrastructure and device processing speed. The network
communication itself is not optimized for speed; for privacy reasons, communication itself is not optimized for speed; for privacy reasons,
the discovery process allows for the Pledge to avoid announcing its the discovery process allows for the pledge to avoid announcing its
presence through broadcasting. presence through broadcasting.
Nomadic or mobile devices often need to aquire credentials to access Nomadic or mobile devices often need to aquire credentials to access
the network at the new location. An example of this is mobile phone the network at the new location. An example of this is mobile phone
roaming among network operators, or even between cell towers. This roaming among network operators, or even between cell towers. This
is usually called handoff. BRSKI does not provide a low-latency is usually called handoff. BRSKI does not provide a low-latency
handoff which is usually a requirement in such situations. For these handoff which is usually a requirement in such situations. For these
solutions BRSKI can be used to create a relationship (an LDevID) with solutions BRSKI can be used to create a relationship (an LDevID) with
the "home" domain owner. The resulting credentials are then used to the "home" domain owner. The resulting credentials are then used to
provide credentials more appropriate for a low-latency handoff. provide credentials more appropriate for a low-latency handoff.
skipping to change at page 10, line 40 skipping to change at page 11, line 10
instance, smart light bulbs are usually mains powered, and speak instance, smart light bulbs are usually mains powered, and speak
802.11). It could also be used by non-constrained devices across a 802.11). It could also be used by non-constrained devices across a
non-energy constrained, but challenged network (such as 802.15.4). non-energy constrained, but challenged network (such as 802.15.4).
The certificate contents, and the process by which the four questions The certificate contents, and the process by which the four questions
above are resolved do apply to constrained devices. It is simply the above are resolved do apply to constrained devices. It is simply the
actual on-the-wire imprint protocol that could be inappropriate. actual on-the-wire imprint protocol that could be inappropriate.
1.3.3. Network Access Controls 1.3.3. Network Access Controls
This document presumes that network access control has either already This document presumes that network access control has either already
occurred, is not required, or is integrated by the Proxy and occurred, is not required, or is integrated by the proxy and
Registrar in such a way that the device itself does not need to be registrar in such a way that the device itself does not need to be
aware of the details. Although the use of an X.509 Initial Device aware of the details. Although the use of an X.509 Initial Device
Identity is consistant with IEEE 802.1AR [IDevID], and allows for Identity is consistant with IEEE 802.1AR [IDevID], and allows for
alignment with 802.1X network access control methods, its use here is alignment with 802.1X network access control methods, its use here is
for Pledge authentication rather than network access control. for pledge authentication rather than network access control.
Integrating this protocol with network access control, perhaps as an Integrating this protocol with network access control, perhaps as an
Extensible Authentication Protocol (EAP) method (see [RFC3748]), is Extensible Authentication Protocol (EAP) method (see [RFC3748]), is
out-of-scope. out-of-scope.
1.4. Leveraging the new key infrastructure / next steps 1.4. Leveraging the new key infrastructure / next steps
As a result of the protocol described herein, the bootstrapped As a result of the protocol described herein, the bootstrapped
devices have the Domain CA trust anchor in common. An end entity devices have the Domain CA trust anchor in common. An end entity
certificate has optionally been issued from the Domain CA. This certificate has optionally been issued from the Domain CA. This
makes it possible to automatically deploy services across the domain makes it possible to automatically deploy services across the domain
skipping to change at page 11, line 36 skipping to change at page 11, line 51
The BRSKI protocol can be used in a number of environments. Some of The BRSKI protocol can be used in a number of environments. Some of
the flexibility in this document is the result of users out of the the flexibility in this document is the result of users out of the
ANI scope. This section defines the base requirements for ANI ANI scope. This section defines the base requirements for ANI
devices. devices.
For devices that intend to become part of an Autonomic Network For devices that intend to become part of an Autonomic Network
Infrastructure (ANI) ([I-D.ietf-anima-reference-model]) that includes Infrastructure (ANI) ([I-D.ietf-anima-reference-model]) that includes
an Autonomic Control Plane an Autonomic Control Plane
([I-D.ietf-anima-autonomic-control-plane]), the following actions are ([I-D.ietf-anima-autonomic-control-plane]), the following actions are
required and MUST be performed by the Pledge: required and MUST be performed by the pledge:
o BRSKI: Request Voucher o BRSKI: Request Voucher
o EST: CA Certificates Request o EST: CA Certificates Request
o EST: CSR Attributes o EST: CSR Attributes
o EST: Client Certificate Request o EST: Client Certificate Request
o BRSKI: Enrollment status Telemetry o BRSKI: Enrollment status Telemetry
skipping to change at page 12, line 28 skipping to change at page 13, line 20
| | S igning |Tracker | | | S igning |Tracker |
| | A uthority | | | | A uthority | |
| +--------------+---------+ | +--------------+---------+
| ^ | ^
| | BRSKI- | | BRSKI-
V | MASA V | MASA
+-------+ ............................................|... +-------+ ............................................|...
| | . | . | | . | .
| | . +------------+ +-----------+ | . | | . +------------+ +-----------+ | .
| | . | | | | | . | | . | | | | | .
|Pledge | . | Circuit | | Domain <-------+ . |Pledge | . | Join | | Domain <-------+ .
| | . | Proxy | | Registrar | . | | . | Proxy | | Registrar | .
| <-------->............<-------> (PKI RA) | . | <-------->............<-------> (PKI RA) | .
| | | BRSKI-EST | | . | | | BRSKI-EST | | .
| | . | | +-----+-----+ . | | . | | +-----+-----+ .
|IDevID | . +------------+ | EST RFC7030 . |IDevID | . +------------+ | EST RFC7030 .
| | . +-----------------+----------+ . | | . +-----------------+----------+ .
| | . | Key Infrastructure | . | | . | Key Infrastructure | .
| | . | (e.g., PKI Certificate | . | | . | (e.g., PKI Certificate | .
+-------+ . | Authority) | . +-------+ . | Authority) | .
. +----------------------------+ . . +----------------------------+ .
skipping to change at page 13, line 6 skipping to change at page 13, line 46
We assume a multi-vendor network. In such an environment there could We assume a multi-vendor network. In such an environment there could
be a Manufacturer Service for each manufacturer that supports devices be a Manufacturer Service for each manufacturer that supports devices
following this document's specification, or an integrator could following this document's specification, or an integrator could
provide a generic service authorized by multiple manufacturers. It provide a generic service authorized by multiple manufacturers. It
is unlikely that an integrator could provide Ownership Tracking is unlikely that an integrator could provide Ownership Tracking
services for multiple manufacturers due to the required sales channel services for multiple manufacturers due to the required sales channel
integrations necessary to track ownership. integrations necessary to track ownership.
The domain is the managed network infrastructure with a Key The domain is the managed network infrastructure with a Key
Infrastructure the Pledge is joining. The domain provides initial Infrastructure the pledge is joining. The domain provides initial
device connectivity sufficient for bootstrapping with a Circuit device connectivity sufficient for bootstrapping through a proxy.
Proxy. The Domain Registrar authenticates the Pledge, makes The domain registrar authenticates the pledge, makes authorization
authorization decisions, and distributes vouchers obtained from the decisions, and distributes vouchers obtained from the Manufacturer
Manufacturer Service. Optionally the Registrar also acts as a PKI Service. Optionally the registrar also acts as a PKI Registration
Registration Authority. Authority.
2.1. Behavior of a Pledge 2.1. Behavior of a Pledge
The Pledge goes through a series of steps, which are outlined here at The pledge goes through a series of steps, which are outlined here at
a high level. a high level.
+--------------+ +--------------+
| Factory | | Factory |
| default | | default |
+------+-------+ +------+-------+
| |
+------v-------+ +------v-------+
| Discover | | (1) Discover |
+------------> | +------------> |
| +------+-------+ | +------+-------+
| | | |
| +------v-------+ | +------v-------+
| | Identity | | | (2) Identity |
^------------+ | ^------------+ |
| rejected +------+-------+ | rejected +------+-------+
| | | |
| +------v-------+ | +------v-------+
| | Request | | | (3) Request |
| | Join | | | Join |
| +------+-------+ | +------+-------+
| | | |
| +------v-------+ | +------v-------+
| | Imprint | Optional | | (4) Imprint |
^------------+ <--+Manual input (Appendix C) ^------------+ |
| Bad MASA +------+-------+ | Bad MASA +------+-------+
| response | send Voucher Status Telemetry | response | send Voucher Status Telemetry
| +------v-------+ | +------v-------+
| | Enroll | | | (5) Enroll |
^------------+ | ^------------+ |
| Enroll +------+-------+ | Enroll +------+-------+
| Failure | | Failure |
| +------v-------+ | +------v-------+
| | Enrolled | | | (6) Enrolled |
^------------+ | ^------------+ |
Factory +--------------+ Factory +--------------+
reset reset
Figure 2 Figure 2
State descriptions for the Pledge are as follows: State descriptions for the pledge are as follows:
1. Discover a communication channel to a Registrar. 1. Discover a communication channel to a registrar.
2. Identify itself. This is done by presenting an X.509 IDevID 2. Identify itself. This is done by presenting an X.509 IDevID
credential to the discovered Registrar (via the Proxy) in a TLS credential to the discovered registrar (via the proxy) in a TLS
handshake. (The Registrar credentials are only provisionally handshake. (The registrar credentials are only provisionally
accepted at this time). accepted at this time).
3. Request to Join the discovered Registrar. A unique nonce can be 3. Request to join the discovered registrar. A unique nonce can be
included ensuring that any responses can be associated with this included ensuring that any responses can be associated with this
particular bootstrapping attempt. particular bootstrapping attempt.
4. Imprint on the Registrar. This requires verification of the 4. Imprint on the registrar. This requires verification of the
manufacturer service provided voucher. A voucher contains manufacturer service provided voucher. A voucher contains
sufficient information for the Pledge to complete authentication sufficient information for the pledge to complete authentication
of a Registrar. (It enables the Pledge to finish authentication of a registrar. (The embedded 'pinned-domain-certificate'
of the Registrar TLS server certificate). enables the pledge to finish authentication of the registrar TLS
server certificate).
5. Enroll. By accepting the domain specific information from a 5. Enroll. By accepting the domain specific information from a
Registrar, and by obtaining a domain certificate from a Registrar registrar, and by obtaining a domain certificate from a registrar
using a standard enrollment protocol, e.g. Enrollment over using a standard enrollment protocol, e.g. Enrollment over
Secure Transport (EST) [RFC7030]. Secure Transport (EST) [RFC7030].
6. The Pledge is now a member of, and can be managed by, the domain 6. The pledge is now a member of, and can be managed by, the domain
and will only repeat the discovery aspects of bootstrapping if it and will only repeat the discovery aspects of bootstrapping if it
is returned to factory default settings. is returned to factory default settings.
After step 4, the pledge has received and authenticated an explicit After imprint a secure transport exists between pledge and registrar.
trust anchor (the pinned-domain-cert in the Voucher response). A This specification details integration with EST enrollment so that
secure transport exists between pledge and registrar, and it may be pledges can optionally obtain a locally issued certificate, although
used for things other than enrollment into a PKI. any REST interface could be integrated in future work.
2.2. Secure Imprinting using Vouchers 2.2. Secure Imprinting using Vouchers
A voucher is a cryptographically protected artifact (a digital A voucher is a cryptographically protected artifact (a digital
signature) to the Pledge device authorizing a zero-touch imprint on signature) to the pledge device authorizing a zero-touch imprint on
the Registrar domain. the registrar domain.
The format and cryptographic mechanism of vouchers is described in The format and cryptographic mechanism of vouchers is described in
detail in [I-D.ietf-anima-voucher]. detail in [I-D.ietf-anima-voucher].
Vouchers provide a flexible mechanism to secure imprinting: the Vouchers provide a flexible mechanism to secure imprinting: the
Pledge device only imprints when a voucher can be validated. At the pledge device only imprints when a voucher can be validated. At the
lowest security levels the MASA server can indiscriminately issue lowest security levels the MASA server can indiscriminately issue
vouchers and log claims of ownership by domains. At the highest vouchers and log claims of ownership by domains. At the highest
security levels issuance of vouchers can be integrated with complex security levels issuance of vouchers can be integrated with complex
sales channel integrations that are beyond the scope of this sales channel integrations that are beyond the scope of this
document. The sales channel integration would verify actual (legal) document. The sales channel integration would verify actual (legal)
ownership of the pledge by the domain. This provides the flexibility ownership of the pledge by the domain. This provides the flexibility
for a number of use cases via a single common protocol mechanism on for a number of use cases via a single common protocol mechanism on
the Pledge and Registrar devices that are to be widely deployed in the pledge and registrar devices that are to be widely deployed in
the field. The MASA services have the flexibility to leverage either the field. The MASA services have the flexibility to leverage either
the currently defined claim mechanisms or to experiment with higher the currently defined claim mechanisms or to experiment with higher
or lower security levels. or lower security levels.
Vouchers provide a signed but non-encrypted communication channel Vouchers provide a signed but non-encrypted communication channel
among the Pledge, the MASA, and the Registrar. The Registrar among the pledge, the MASA, and the registrar. The registrar
maintains control over the transport and policy decisions allowing maintains control over the transport and policy decisions allowing
the local security policy of the domain network to be enforced. the local security policy of the domain network to be enforced.
2.3. Initial Device Identifier 2.3. Initial Device Identifier
Pledge authentication and Pledge voucher-request signing is via a Pledge authentication and pledge voucher-request signing is via a
PKIX certificate installed during the manufacturing process. This is PKIX certificate installed during the manufacturing process. This is
the 802.1AR Initial Device Identifier (IDevID), and it provides a the 802.1AR Initial Device Identifier (IDevID), and it provides a
basis for authenticating the Pledge during the protocol exchanges basis for authenticating the pledge during the protocol exchanges
described here. There is no requirement for a common root PKI described here. There is no requirement for a common root PKI
hierarchy. Each device manufacturer can generate its own root hierarchy. Each device manufacturer can generate its own root
certificate. Specifically, the IDevID: certificate. Specifically, the IDevID:
1. Uniquely identifying the pledge by the Distinguished Name (DN) 1. Uniquely identifying the pledge by the Distinguished Name (DN)
and subjectAltName (SAN) parameters in the IDevID. The unique and subjectAltName (SAN) parameters in the IDevID. The unique
identification of a pledge in the voucher objects are derived identification of a pledge in the voucher objects are derived
from those parameters as described below. from those parameters as described below.
2. Securely authentating the pledges identity via TLS connection to 2. Securely authentating the pledges identity via TLS connection to
skipping to change at page 16, line 44 skipping to change at page 16, line 48
enable MASA to generate voucher only to a registrar that has a enable MASA to generate voucher only to a registrar that has a
connection to the pledge. connection to the pledge.
6. Authorizing pledge (via registrar) to receive certificate from 6. Authorizing pledge (via registrar) to receive certificate from
domain CA, by signing the Certificate Signing Request (CSR). domain CA, by signing the Certificate Signing Request (CSR).
2.3.1. Identification of the Pledge 2.3.1. Identification of the Pledge
In the context of BRSKI, pledges are uniquely identified by a In the context of BRSKI, pledges are uniquely identified by a
"serial-number". This serial-number is used both in the "serial- "serial-number". This serial-number is used both in the "serial-
number" field of Voucher or Voucher requests (see Section 3) and in number" field of voucher or voucher-requests (see Section 3) and in
local policies on Registrar or MASA (see Section 5). local policies on registrar or MASA (see Section 5).
The following fields are defined in [IDevID] and [RFC5280]: The following fields are defined in [IDevID] and [RFC5280]:
o The subject field's DN encoding MUST include the "serialNumber" o The subject field's DN encoding MUST include the "serialNumber"
attribute with the device's unique serial number. (from [IDevID] attribute with the device's unique serial number. (from [IDevID]
section 7.2.8, and [RFC5280] section 4.1.2.4's list of standard section 7.2.8, and [RFC5280] section 4.1.2.4's list of standard
attributes) attributes)
o The subject-alt field's encoding MAY include a non-critical o The subject-alt field's encoding MAY include a non-critical
version of the RFC4108 defined HardwareModuleName. (from [IDevID] version of the RFC4108 defined HardwareModuleName. (from [IDevID]
section 7.2.9) If the IDevID is stored in a Trusted Platform section 7.2.9) If the IDevID is stored in a Trusted Platform
Module (TPM), then this field MAY contain the TPM identification Module (TPM), then this field MAY contain the TPM identification
rather than the device's serial number. If both fields are rather than the device's serial number. If both fields are
present, then the subject field takes precedence. present, then the subject field takes precedence.
and they are used as follows to build pledge "serial-number". In and they are used as follows by the pledge to build the "serial-
order to build it, the fields need to be converted into a serial- number" that is placed in the voucher-request. In order to build it,
number of "type string". The following methods are used depending on the fields need to be converted into a serial-number of "type
the first available IDevID certificate field (attempted in this string". The following methods are used depending on the first
order): available IDevID certificate field (attempted in this order):
1. [RFC4519] section 2.31 provides an example ("WI-3005") of the 1. [RFC4519] section 2.31 provides an example ("WI-3005") of the
Distinguished Name "serialNumber" attribute, formatted according Distinguished Name "serialNumber" attribute, formatted according
to RFC4514 rules. to RFC4514 rules.
2. The HardwareModuleName hwSerialNum OCTET STRING, base64 encoded. 2. The HardwareModuleName hwSerialNum OCTET STRING, base64 encoded.
2.3.2. MASA URI extension 2.3.2. MASA URI extension
The following newly defined field SHOULD be in the PKIX IDevID The following newly defined field SHOULD be in the PKIX IDevID
skipping to change at page 19, line 7 skipping to change at page 19, line 7
[RFC5280], "These extensions may be used to direct applications to [RFC5280], "These extensions may be used to direct applications to
on-line information about the issuer or the subject". The MASA URL on-line information about the issuer or the subject". The MASA URL
is precisely that: online information about the particular subject. is precisely that: online information about the particular subject.
2.4. Protocol Flow 2.4. Protocol Flow
A representative flow is shown in Figure 3: A representative flow is shown in Figure 3:
+--------+ +---------+ +------------+ +------------+ +--------+ +---------+ +------------+ +------------+
| Pledge | | Circuit | | Domain | | Vendor | | Pledge | | Circuit | | Domain | | Vendor |
| | | Proxy | | Registrar | | Service | | | | Join | | Registrar | | Service |
| | | | | (JRC) | | (MASA) | | | | Proxy | | (JRC) | | (MASA) |
+--------+ +---------+ +------------+ +------------+ +--------+ +---------+ +------------+ +------------+
| | | Internet | | | | Internet |
|<-RFC4862 IPv6 addr | | | |<-RFC4862 IPv6 addr | | |
|<-RFC3927 IPv4 addr | Appendix A | Legend | |<-RFC3927 IPv4 addr | Appendix A | Legend |
|-------------------->| | C - circuit | |-------------------->| | C - circuit |
| optional: mDNS query| Appendix B | proxy | | optional: mDNS query| Appendix B | join proxy |
| RFC6763/RFC6762 | | P - provisional | | RFC6763/RFC6762 | | P - provisional |
|<--------------------| | TLS connection | |<--------------------| | TLS connection |
| GRASP M_FLOOD | | | | GRASP M_FLOOD | | |
| periodic broadcast| | | | periodic broadcast| | |
|<------------------->C<----------------->| | |<------------------->C<----------------->| |
| TLS via the Circuit Proxy | | | TLS via the Join Proxy | |
|<--Registrar TLS server authentication---| | |<--Registrar TLS server authentication---| |
[PROVISIONAL accept of server cert] | | [PROVISIONAL accept of server cert] | |
P---X.509 client authentication---------->| | P---X.509 client authentication---------->| |
P | | | P | | |
P---Voucher Request (include nonce)------>| | P---Voucher Request (include nonce)------>| |
P | /---> | | P | /---> | |
P | | [accept device?] | P | | [accept device?] |
P | | [contact Vendor] | P | | [contact Vendor] |
P | | |--Pledge ID-------->| P | | |--Pledge ID-------->|
P | | |--Domain ID-------->| P | | |--Domain ID-------->|
skipping to change at page 20, line 9 skipping to change at page 20, line 9
| Continue with RFC7030 enrollment | | | Continue with RFC7030 enrollment | |
| using now bidirectionally authenticated | | | using now bidirectionally authenticated | |
| TLS session. | | | | TLS session. | | |
Figure 3 Figure 3
2.5. Architectural Components 2.5. Architectural Components
2.5.1. Pledge 2.5.1. Pledge
The Pledge is the device that is attempting to join. Until the The pledge is the device that is attempting to join. Until the
Pledge completes the enrollment process, it has link-local network pledge completes the enrollment process, it has link-local network
connectivity only to the Proxy. connectivity only to the proxy.
2.5.2. Circuit Proxy 2.5.2. Join Proxy
The (Circuit) Proxy provides HTTPS connectivity between the Pledge The join proxy provides HTTPS connectivity between the pledge and the
and the Registrar. The circuit proxy mechanism is described in registrar. A circuit proxy mechanism is described in Section 4, with
Section 4, with an optional stateless proxy mechanism described in an optional stateless IPIP proxy mechanism described in Appendix C.
Appendix C.
2.5.3. Domain Registrar 2.5.3. Domain Registrar
The domain's Registrar operates as the BRSKI-MASA client when The domain's registrar operates as the BRSKI-MASA client when
requesting vouchers from the MASA (see Section 5.3). The Registrar requesting vouchers from the MASA (see Section 5.3). The registrar
operates as the BRSKI-EST server when Pledges request vouchers (see operates as the BRSKI-EST server when pledges request vouchers (see
Section 5.1). The Registrar operates as the BRSKI-EST server Section 5.1). The registrar operates as the BRSKI-EST server
"Registration Authority" if the Pledge requests an end entity "Registration Authority" if the pledge requests an end entity
certificate over the BRSKI-EST connection (see Section 5.8). certificate over the BRSKI-EST connection (see Section 5.8).
The Registar uses an Implicit Trust Anchor database for The registrar uses an Implicit Trust Anchor database for
authenticating the BRSKI-MASA TLS connection MASA server certificate. authenticating the BRSKI-MASA TLS connection MASA server certificate.
The Registrar uses a different Implicit Trust Anchor database for The registrar uses a different Implicit Trust Anchor database for
authenticating the BRSKI-EST TLS connection Pledge client authenticating the BRSKI-EST TLS connection pledge client
certificate. Configuration or distribution of these trust anchor certificate. Configuration or distribution of these trust anchor
databases is out-of-scope of this specification. databases is out-of-scope of this specification.
2.5.4. Manufacturer Service 2.5.4. Manufacturer Service
The Manufacturer Service provides two logically seperate functions: The Manufacturer Service provides two logically seperate functions:
the Manufacturer Authorized Signing Authority (MASA) described in the Manufacturer Authorized Signing Authority (MASA) described in
Section 5.4 and Section 5.5, and an ownership tracking/auditing Section 5.4 and Section 5.5, and an ownership tracking/auditing
function described in Section 5.6 and Section 5.7. function described in Section 5.6 and Section 5.7.
2.5.5. Public Key Infrastructure (PKI) 2.5.5. Public Key Infrastructure (PKI)
The Key Infrastructure (PKI) administers certificates for the domain The Public Key Infrastructure (PKI) administers certificates for the
of concerns, providing the trust anchor(s) for it and allowing domain of concerns, providing the trust anchor(s) for it and allowing
enrollment of Pledges with domain certificates. enrollment of pledges with domain certificates.
The domain's Registrar uses the "pinned-domain-cert" voucher field to The voucher provides a method for the distribution of a single PKI
distribute a trust anchor for authenticating itself to the Pledge. trust anchor (as the "pinned-domain-cert"). A distribution of the
full set of current trust anchors is possible using the optional EST
integration.
The domain's Registrar acts as an [RFC5272] Registration Authority, The domain's registrar acts as an [RFC5272] Registration Authority,
requesting certificates for Pledges from the Key Infrastructure. requesting certificates for pledges from the Key Infrastructure.
The above requirements and expectations against the Key The expectations of the PKI are unchanged from EST [[RFC7030]]. This
Infrastructure are unchanged from RFC7030. This document does not document does not place any additional architectural requirements on
place any additional architectural requirements on the Public Key the Public Key Infrastructure.
Infrastructure.
2.6. Certificate Time Validation 2.6. Certificate Time Validation
2.6.1. Lack of realtime clock 2.6.1. Lack of realtime clock
Many devices when bootstrapping do not have knowledge of the current Many devices when bootstrapping do not have knowledge of the current
time. Mechanisms such as Network Time Protocols cannot be secured time. Mechanisms such as Network Time Protocols cannot be secured
until bootstrapping is complete. Therefore bootstrapping is defined until bootstrapping is complete. Therefore bootstrapping is defined
in a method that does not require knowledge of the current time. in a method that does not require knowledge of the current time.
Unfortunately there are moments during bootstrapping when Unfortunately there are moments during bootstrapping when
certificates are verified, such as during the TLS handshake, where certificates are verified, such as during the TLS handshake, where
validity periods are confirmed. This paradoxical "catch-22" is validity periods are confirmed. This paradoxical "catch-22" is
resolved by the Pledge maintaining a concept of the current "window" resolved by the pledge maintaining a concept of the current "window"
of presumed time validity that is continually refined throughout the of presumed time validity that is continually refined throughout the
bootstrapping process as follows: bootstrapping process as follows:
o Initially the Pledge does not know the current time. o Initially the pledge does not know the current time.
o Bootstrapping Pledges that have a Realtime Clock (RTC), SHOULD use o Bootstrapping pledges that have a Realtime Clock (RTC), SHOULD use
it to verify certificate validity. However, they MUST be prepared it to verify certificate validity. However, they MUST be prepared
for the recognize that the RTC might be completely wrong when a for the recognize that the RTC might be completely wrong when a
RTC battery fails and resets to an origin time (e.g., Jan. 1, RTC battery fails and resets to an origin time (e.g., Jan. 1,
1970) 1970)
o If the Pledge has any stable storage (such as from where firmware o If the pledge has any stable storage (such as from where firmware
is loaded) then it SHOULD assume that the clock CAN NOT be before is loaded) then it SHOULD assume that the clock CAN NOT be before
the date at which the firmware or the the storage was last time the date at which the firmware or the the storage was last time
stamped. The Pledge SHOULD NOT update the timestamps in any file stamped. The pledge SHOULD NOT update the timestamps in any file
systems until it has a secure time source. This provides an systems until it has a secure time source. This provides an
earliest date which is reasonable. Call this the current earliest date which is reasonable. Call this the current
reasonable date (CRD). This value SHOULD NOT be stored in any reasonable date (CRD). This value MUST NOT be used for any future
way, and applies to the current Registration attempt only. Registration attempt. The current reasonable date (CRD) may only
Subsequent attempts MUST follow this proceedure again from increase during a single attempt.
scratch. The current reasonable date may only increase.
o The Pledge is exposed to dates in the following five places o The pledge is exposed to dates in the following five places
(Registrar certificate, notBefore and notAfter. Voucher created- (registrar certificate, notBefore and notAfter. Voucher created-
on, and expires-on. Additionally, CMS signatures contain a on, and expires-on. Additionally, CMS signatures contain a
signingTime) signingTime)
o During the initial connection with the Registrar, the Pledge sees o During the initial connection with the registrar, the pledge sees
the Registrar Certificate. It has an inception date (notBefore) the registrar's Certificate. It has an inception date (notBefore)
and an expiry date (notAfter). It is reasonable that the and an expiry date (notAfter). It is reasonable that the
notBefore date be after the Pledge's current working reasonable notBefore date be after the pledge's current working reasonable
date. It is however, suspicious for the notAfter date to be date. It is however, suspicious for the notAfter date to be
before the Pledge's current reasonable date. No action is before the pledge's current reasonable date. No action is
recommended, other than an internal audit entry for this. recommended, other than an internal audit entry for this.
o If the notBefore date of the Registrar's certificate is newer than o If the notBefore date of the registrar's certificate is newer than
the Pledge's reasonable date, then it MAY update it's current the pledge's reasonable date, then it MAY update it's current
reasonable date to the notBefore value. reasonable date to the notBefore value.
o After the voucher request process, the pledge will have a voucher. o After the voucher request process, the pledge will have a voucher.
It can validate the signature on the voucher, as it has been (by It can validate the signature on the voucher, as it has been (by
literal construction) provided with the MASA's key as a trust literal construction) provided with the MASA's key as a trust
anchor. The time values (created-on, expires-on) in the voucher anchor. The time values (created-on, expires-on) in the voucher
can not in general be validated as the Pledge has no certain real can not in general be validated as the pledge has no certain real
time clock. There are some reasonable assumptions that can be time clock. There are some reasonable assumptions that can be
made: the voucher's expires-on time can not be prior to the the made: the voucher's expires-on time can not be prior to the
Pledge's current reasonable date. For nonceless vouchers, the pledge's current reasonable date. For nonceless vouchers, the
voucher's created-on time COULD be earlier if the as well if a voucher's created-on time COULD be earlier if the as well if a
long-lived voucher was obtained some time in the past, and the long-lived voucher was obtained some time in the past, and the
Pledge has since gone through a firmware update and factory reset. pledge has since gone through a firmware update and factory reset.
o If the voucher contains a nonce then the Pledge MUST confirm the o If the voucher contains a nonce then the pledge MUST confirm the
nonce matches the original Pledge voucher-request. This ensures nonce matches the original pledge voucher-request. This ensures
the voucher is fresh. See / (Section 5.2). In that case, the the voucher is fresh. See / (Section 5.2). In that case, the
voucher's created-on date MUST NOT be prior to the Pledge's voucher's created-on date MUST NOT be prior to the pledge's
current reasonable date. In addition, when there is a valid current reasonable date. In addition, when there is a valid
nonce, the current reasonable date MAY be incremented to that of nonce, the current reasonable date MAY be incremented to that of
the CMS signingTime. the CMS signingTime.
o Once the voucher is accepted the validity period of the pinned- o Once the voucher is accepted the validity period of the pinned-
domain-cert in the voucher now serves as a valid time window. As domain-cert in the voucher now serves as a valid time window. As
explained in Section 5.4.3, the MASA has checked the Registrar's explained in Section 5.4.4, the MASA has checked the registrar's
certificate against real clocks , the endorsement of the MASA certificate against real clocks , the endorsement of the MASA
allows the Pledge to treat the notBefore and notAfter dates as allows the pledge to treat the notBefore and notAfter dates as
being constrained on any subsequent certificate validity periods being constraints on any subsequent certificate validity periods
that may need to be checked: for instance, validating peer that may need to be checked: for instance, validating peer
certificates during ANIMA ACP setup. certificates during ANIMA ACP setup.
o When accepting an enrollment certificate the validity period o When accepting an enrollment certificate the validity period
within the new certificate is assumed to be valid by the Pledge. within the new certificate is assumed to be valid by the pledge.
The Pledge is now willing to use this credential for client The pledge is now willing to use this credential for client
authentication. authentication.
o
2.6.2. Infinite Lifetime of IDevID 2.6.2. Infinite Lifetime of IDevID
[RFC5280] explains that long lived Pledge certificates "SHOULD be [RFC5280] explains that long lived pledge certificates "SHOULD be
assigned the GeneralizedTime value of 99991231235959Z". Registrars assigned the GeneralizedTime value of 99991231235959Z". Registrars
MUST support such lifetimes and SHOULD support ignoring Pledge MUST support such lifetimes and SHOULD support ignoring pledge
lifetimes if they did not follow the RFC5280 recommendations. lifetimes if they did not follow the RFC5280 recommendations.
For example, IDevID may have incorrect lifetime of N <= 3 years, For example, IDevID may have incorrect lifetime of N <= 3 years,
rendering replacement Pledges from storage useless after N years rendering replacement pledges from storage useless after N years
unless registrars support ignoring such a lifetime. unless registrars support ignoring such a lifetime.
2.7. Cloud Registrar 2.7. Cloud Registrar
There exist operationally open network wherein device gains There exist operationally open network wherein devices gain
unauthenticated access to the internet at large. In these use cases unauthenticated access to the internet at large. In these use cases
the management domain for the device needs to be discovered within the management domain for the device needs to be discovered within
the larger internet. These are less likely within the anima scope the larger internet. These are less likely within the anima scope
but may be more important in the future. but may be more important in the future.
There are additionally some greenfield situations involving an There are additionally some greenfield situations involving an
entirely new installation where a device may have some kind of entirely new installation where a device may have some kind of
management uplink that it can use (such as via 3G network for management uplink that it can use (such as via 3G network for
instance). In such a future situation, the device might use this instance). In such a future situation, the device might use this
management interface to learn that it should configure itself by to- management interface to learn that it should configure itself by to-
be-determined mechanism (such as an Intent) to become the local be-determined mechanism (such as an Intent) to become the local
Registrar. registrar.
In order to support these scenarios, the Pledge MAY contact a well In order to support these scenarios, the pledge MAY contact a well
known URI of a cloud Registrar if a local Registrar cannot be 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 discovered or if the pledge's target use cases do not include a local
Registrar. registrar.
If the Pledge uses a well known URI for contacting a cloud Registrar If the pledge uses a well known URI for contacting a cloud registrar
an Implicit Trust Anchor database (see [RFC7030]) MUST be used to an Implicit Trust Anchor database (see [RFC7030]) MUST be used to
authenticate service as described in [RFC6125]. This is consistent authenticate service as described in [RFC6125]. This is consistent
with the human user configuration of an EST server URI in [RFC7030] with the human user configuration of an EST server URI in [RFC7030]
which also depends on RFC6125. which also depends on RFC6125.
2.8. Determining the MASA to contact 2.8. Determining the MASA to contact
The Registrar needs to be able to contact a MASA that is trusted by The registrar needs to be able to contact a MASA that is trusted by
the Pledge in order to obtain vouchers. There are three mechanisms the pledge in order to obtain vouchers. There are three mechanisms
described: described:
The device's Initial Device Identifier will normally contain the MASA The device's Initial Device Identifier will normally contain the MASA
URL as detailed in Section 2.3. This is the RECOMMENDED mechanism. URL as detailed in Section 2.3. This is the RECOMMENDED mechanism.
If the Registrar is integrated with [I-D.ietf-opsawg-mud] and the If the registrar is integrated with [I-D.ietf-opsawg-mud] and the
Pledge IDevID contains the id-pe-mud-url then the Registrar MAY pledge IDevID contains the id-pe-mud-url then the registrar MAY
attempt to obtain the MASA URL from the MUD file. The MUD file attempt to obtain the MASA URL from the MUD file. The MUD file
extension for the MASA URL is defined in Appendix D. extension for the MASA URL is defined in Appendix D.
It can be operationally difficult to ensure the necessary X.509 It can be operationally difficult to ensure the necessary X.509
extensions are in the Pledge's IDevID due to the difficulty of extensions are in the pledge's IDevID due to the difficulty of
aligning current Pledge manufacturing with software releases and aligning current pledge manufacturing with software releases and
development. As a final fallback the Registrar MAY be manually development. As a final fallback the registrar MAY be manually
configured or distributed with a MASA URL for each manufacturer. configured or distributed with a MASA URL for each manufacturer.
Note that the Registrar can only select the configured MASA URL based Note that the registrar can only select the configured MASA URL based
on the trust anchor -- so manufacturers can only leverage this on the trust anchor -- so manufacturers can only leverage this
approach if they ensure a single MASA URL works for all Pledge's approach if they ensure a single MASA URL works for all pledge's
associated with each trust anchor. associated with each trust anchor.
3. Voucher-Request artifact 3. Voucher-Request artifact
Voucher-requests are how vouchers are requested. The semantics of Voucher-requests are how vouchers are requested. The semantics of
the vouchers are described below, in the YANG model. the vouchers are described below, in the YANG model.
A Pledge forms the "Pledge voucher-request" and submits it to the A pledge forms the "pledge voucher-request" and submits it to the
Registrar. registrar.
The Registrar in turn forms the "Registrar voucher-request", and The registrar in turn forms the "registrar voucher-request", and
submits it to the MASA server. submits it to the MASA server.
The "proximity-registrar-cert" leaf is used in the Pledge voucher- The "proximity-registrar-cert" leaf is used in the pledge voucher-
requests. This provides a method for the Pledge to assert the requests. This provides a method for the pledge to assert the
Registrar's proximity. registrar's proximity.
The "prior-signed-voucher-request" leaf is used in Registrar voucher- The "prior-signed-voucher-request" leaf is used in registrar voucher-
requests. If present, it is the encoded (signed form) of the Pledge requests. If present, it is the encoded (signed form) of the pledge
voucher-request. This provides a method for the Registrar to forward voucher-request. This provides a method for the registrar to forward
the Pledge's signed request to the MASA. This completes transmission the pledge's signed request to the MASA. This completes transmission
of the signed "proximity-registrar-cert" leaf. of the signed "proximity-registrar-cert" leaf.
A Registar MAY also retrieve nonceless vouchers by sending nonceless A registrar MAY also retrieve nonceless vouchers by sending nonceless
voucher-requests to the MASA in order to obtain vouchers for later voucher-requests to the MASA in order to obtain vouchers for use when
offline use. No "prior-signed-voucher-request" leaf would be the registrar does not have connectivity to the MASA. No "prior-
included. The Registrar will also need to know the serial number of signed-voucher-request" leaf would be included. The registrar will
the pledge. This document does not provide a mechanism for the also need to know the serial number of the pledge. This document
Registrar to learn that in an automated fashion. Typically this will does not provide a mechanism for the registrar to learn that in an
be done via scanning of bar-code or QR-code on packaging, or via some automated fashion. Typically this will be done via scanning of bar-
sales channel integration. code or QR-code on packaging, or via some sales channel integration.
Unless otherwise signaled (outside the voucher-request artifact), the Unless otherwise signaled (outside the voucher-request artifact), the
signing structure is as defined for vouchers, see signing structure is as defined for vouchers, see
[I-D.ietf-anima-voucher]. [I-D.ietf-anima-voucher].
3.1. Tree Diagram 3.1. Tree Diagram
The following tree diagram illustrates a high-level view of a The following tree diagram illustrates a high-level view of a
voucher-request document. The notation used in this diagram is voucher-request document. The notation used in this diagram is
described in [I-D.ietf-anima-voucher]. Each node in the diagram is described in [I-D.ietf-anima-voucher]. Each node in the diagram is
skipping to change at page 25, line 35 skipping to change at page 25, line 35
+---- last-renewal-date? yang:date-and-time +---- last-renewal-date? yang:date-and-time
+---- prior-signed-voucher-request? binary +---- prior-signed-voucher-request? binary
+---- proximity-registrar-cert? binary +---- proximity-registrar-cert? binary
3.2. Examples 3.2. Examples
This section provides voucher-request examples for illustration This section provides voucher-request examples for illustration
purposes. These examples conform to the encoding rules defined in purposes. These examples conform to the encoding rules defined in
[RFC7951]. [RFC7951].
Example (1) The following example illustrates a Pledge voucher- Example (1) The following example illustrates a pledge voucher-
request. The assertion leaf is indicated as 'proximity' request. The assertion leaf is indicated as 'proximity'
and the Registrar's TLS server certificate is included and the registrar's TLS server certificate is included
in the 'proximity-registrar-cert' leaf. See in the 'proximity-registrar-cert' leaf. See
Section 5.2. Section 5.2.
{ {
"ietf-voucher-request:voucher": { "ietf-voucher-request:voucher": {
"nonce": "62a2e7693d82fcda2624de58fb6722e5", "nonce": "62a2e7693d82fcda2624de58fb6722e5",
"created-on": "2017-01-01T00:00:00.000Z", "created-on": "2017-01-01T00:00:00.000Z",
"assertion": "proximity", "assertion": "proximity",
"proximity-registrar-cert": "base64encodedvalue==" "proximity-registrar-cert": "base64encodedvalue=="
} }
} }
Example (2) The following example illustrates a Registrar voucher- Example (2) The following example illustrates a registrar voucher-
request. The 'prior-signed-voucher-request' leaf is request. The 'prior-signed-voucher-request' leaf is
populated with the Pledge's voucher-request (such as the populated with the pledge's voucher-request (such as the
prior example). The Pledge's voucher-request, if a prior example). The pledge's voucher-request, if a
signed artifact with a CMS format signature is a binary signed artifact with a CMS format signature is a binary
object. In the JSON encoding used here it must be object. In the JSON encoding used here it must be
base64 encoded. The nonce, created-on and assertion is base64 encoded. The nonce, created-on and assertion is
carried forward. serial-number is extracted from the carried forward. serial-number is extracted from the
Pledge's Client Certificate from the TLS connection. pledge's Client Certificate from the TLS connection.
See Section 5.4. See Section 5.4.
{ {
"ietf-voucher-request:voucher": { "ietf-voucher-request:voucher": {
"nonce": "62a2e7693d82fcda2624de58fb6722e5", "nonce": "62a2e7693d82fcda2624de58fb6722e5",
"created-on": "2017-01-01T00:00:02.000Z", "created-on": "2017-01-01T00:00:02.000Z",
"assertion": "proximity", "assertion": "proximity",
"idevid-issuer": "base64encodedvalue==" "idevid-issuer": "base64encodedvalue=="
"serial-number": "JADA123456789" "serial-number": "JADA123456789"
"prior-signed-voucher": "base64encodedvalue==" "prior-signed-voucher": "base64encodedvalue=="
} }
} }
Example (3) The following example illustrates a Registrar voucher- Example (3) The following example illustrates a registrar voucher-
request. The 'prior-signed-voucher-request' leaf is not request. The 'prior-signed-voucher-request' leaf is not
populated with the Pledge's voucher-request nor is the populated with the pledge's voucher-request nor is the
nonce leaf. This form might be used by a Registrar nonce leaf. This form might be used by a registrar
requesting a voucher when the Pledge is offline or when requesting a voucher when the pledge can not communicate
the Registrar expects to be offline during deployment. with the registrar (such as when it is powered down, or
See Section 5.4. still in packaging), and therefore could not submit a
nonce. This scenario is most useful when the registrar
is aware that it will not be able to reach the MASA
during deployment. See Section 5.4.
{ {
"ietf-voucher-request:voucher": { "ietf-voucher-request:voucher": {
"created-on": "2017-01-01T00:00:02.000Z", "created-on": "2017-01-01T00:00:02.000Z",
"assertion": "TBD", "assertion": "TBD",
"idevid-issuer": "base64encodedvalue==" "idevid-issuer": "base64encodedvalue=="
"serial-number": "JADA123456789" "serial-number": "JADA123456789"
} }
} }
Example (4) The following example illustrates a Registrar voucher- Example (4) The following example illustrates a registrar voucher-
request. The 'prior-signed-voucher-request' leaf is not request. The 'prior-signed-voucher-request' leaf is not
populated with the Pledge voucher-request because the populated with the pledge voucher-request because the
Pledge did not sign its own request. This form might be pledge did not sign its own request. This form might be
used when more constrained Pledges are being deployed. used when more constrained pledges are being deployed.
The nonce is populated from the Pledge's request. See The nonce is populated from the pledge's request. See
Section 5.4. Section 5.4.
{ {
"ietf-voucher-request:voucher": { "ietf-voucher-request:voucher": {
"nonce": "62a2e7693d82fcda2624de58fb6722e5", "nonce": "62a2e7693d82fcda2624de58fb6722e5",
"created-on": "2017-01-01T00:00:02.000Z", "created-on": "2017-01-01T00:00:02.000Z",
"assertion": "proximity", "assertion": "proximity",
"idevid-issuer": "base64encodedvalue==" "idevid-issuer": "base64encodedvalue=="
"serial-number": "JADA123456789" "serial-number": "JADA123456789"
} }
skipping to change at page 29, line 38 skipping to change at page 29, line 38
proximity assertion. This is a simple mechanism for a proximity assertion. This is a simple mechanism for a
chain of trusted parties to change a voucher, while chain of trusted parties to change a voucher, while
maintaining the prior signature information. maintaining the prior signature information.
The pledge MUST ignore all prior voucher information when The pledge MUST ignore all prior voucher information when
accepting a voucher for imprinting. Other parties MAY accepting a voucher for imprinting. Other parties MAY
examine the prior signed voucher information for the examine the prior signed voucher information for the
purposes of policy decisions. For example this information purposes of policy decisions. For example this information
could be useful to a MASA to determine that both pledge and could be useful to a MASA to determine that both pledge and
registrar agree on proximity assertions. The MASA SHOULD registrar agree on proximity assertions. The MASA SHOULD
remove all prior-signed-voucher information when signing remove all prior-signed-voucher-request information when
a voucher for imprinting so as to minimize the final signing a voucher for imprinting so as to minimize the
voucher size."; final voucher size.";
} }
leaf proximity-registrar-cert { leaf proximity-registrar-cert {
type binary; type binary;
description description
"An X.509 v3 certificate structure as specified by RFC 5280, "An X.509 v3 certificate structure as specified by RFC 5280,
Section 4 encoded using the ASN.1 distinguished encoding Section 4 encoded using the ASN.1 distinguished encoding
rules (DER), as specified in ITU-T X.690. rules (DER), as specified in ITU-T X.690.
The first certificate in the Registrar TLS server The first certificate in the Registrar TLS server
skipping to change at page 30, line 17 skipping to change at page 30, line 17
} }
} }
} }
} }
<CODE ENDS> <CODE ENDS>
4. Proxying details (Pledge - Proxy - Registrar) 4. Proxying details (Pledge - Proxy - Registrar)
The role of the Proxy is to facilitate communications. The Proxy The role of the proxy is to facilitate communications. The proxy
forwards packets between the Pledge and a Registrar that has been forwards packets between the pledge and a registrar that has been
provisioned to the Proxy via GRASP discovery. provisioned to the proxy via GRASP discovery.
This section defines a stateful proxy mechanism which is refered to This section defines a stateful proxy mechanism which is refered to
as a "circuit" proxy. as a "circuit" proxy.
The Proxy does not terminate the TLS handshake: it passes streams of The proxy does not terminate the TLS handshake: it passes streams of
bytes onward without examination. bytes onward without examination.
A Proxy MAY assume TLS framing for auditing purposes, but MUST NOT A proxy MAY assume TLS framing for auditing purposes, but MUST NOT
assume any TLS version. assume any TLS version.
Registrars are assumed to have logically a locally integrated Proxy Registrars are assumed to have logically a locally integrated circuit
to support directly (subnet) connected Pledges - because Registrars proxy to support directly (subnet) connected pledges - because
themself does not define any functions for Pledges to discover them. registrars themself does not define any functions for pledges to
Such a logical local proxy does not need to provide actual TCP discover them. Such a logical local proxy does not need to provide
proxying (just discovery) as long as the Registrar can operate with actual TCP proxying (just discovery) as long as the registrar can
subnet (link) local addresses on the interfaces where Pledges may operate with subnet (link) local addresses on the interfaces where
connect to. pledges may connect to.
As a result of the Proxy Discovery process in Section 4.1.1, the port As a result of the proxy Discovery process in Section 4.1.1, the port
number exposed by the Proxy does not need to be well known, or number exposed by the proxy does not need to be well known, or
require an IANA allocation. require an IANA allocation.
In the ANI, the Autonomic Control Plane (ACP) secured instance of In the ANI, the Autonomic Control Plane (ACP) secured instance of
GRASP ([I-D.ietf-anima-grasp]) MUST be used for discovery of ANI GRASP ([I-D.ietf-anima-grasp]) MUST be used for discovery of ANI
Registrar ACP addresses and ports by ANI Proxies. The TCP leg of the registrar ACP addresses and ports by ANI proxies. The TCP leg of the
proxy connection between ANI Proxy and ANI Registrar therefore also proxy connection between ANI proxy and ANI registrar therefore also
runs across the ACP. runs across the ACP.
If GRASP is used by proxies for discovery of Registrars (ACP or not), During the discovery of the Registrar by the Join Proxy, the Join
the proxy can also learn the proxy mechanism (Circuit Proxy vs. IPIP Proxy will also learn which kinds of proxy mechanisms are available.
encapsulation or other) This will allow the Join Proxy to use the lowest impact mechanism
which the Join Proxy and Registrar have in common.
For the IPIP encapsulation methods (described in Appendix C), the For the IPIP encapsulation methods (described in Appendix C), the
port announced by the Proxy SHOULD be the same as on the Registrar in port announced by the proxy SHOULD be the same as on the registrar in
order for the Proxy to remain stateless. order for the proxy to remain stateless.
In order to permit the Proxy functionality to be implemented on the In order to permit the proxy functionality to be implemented on the
maximum variety of devices the chosen mechanism SHOULD use the maximum variety of devices the chosen mechanism SHOULD use the
minimum amount of state on the Proxy device. While many devices in minimum amount of state on the proxy device. While many devices in
the ANIMA target space will be rather large routers, the Proxy the ANIMA target space will be rather large routers, the proxy
function is likely to be implemented in the control plane CPU of such function is likely to be implemented in the control plane CPU of such
a device, with available capabilities for the Proxy function similar a device, with available capabilities for the proxy function similar
to many class 2 IoT devices. to many class 2 IoT devices.
The document [I-D.richardson-anima-state-for-joinrouter] provides a The document [I-D.richardson-anima-state-for-joinrouter] provides a
more extensive analysis and background of the alternative Proxy more extensive analysis and background of the alternative proxy
methods. methods.
4.1. Pledge discovery of Proxy 4.1. Pledge discovery of Proxy
The result of discovery is a logical communication with a Registrar, The result of discovery is a logical communication with a registrar,
through a Proxy. The Proxy is transparent to the Pledge but is through a proxy. The proxy is transparent to the pledge but is
always assumed to exist. always assumed to exist.
To discover the Proxy the Pledge performs the following actions: To discover the proxy the pledge performs the following actions:
1. MUST: Obtains a local address using IPv6 methods as described in 1. MUST: Obtains a local address using IPv6 methods as described in
[RFC4862] IPv6 Stateless Address AutoConfiguration. Use of [RFC4862] IPv6 Stateless Address AutoConfiguration. Use of
[RFC4941] temporary addresses is encouraged. A new temporary [RFC4941] temporary addresses is encouraged. A new temporary
address SHOULD be allocated whenever the discovery process is address SHOULD be allocated whenever the discovery process is
forced to restart due to failures. Pledges will generally prefer forced to restart due to failures. Pledges will generally prefer
use of IPv6 Link-Local addresses, and discovery of Proxy will be use of IPv6 Link-Local addresses, and discovery of proxy will be
by Link-Local mechanisms. IPv4 methods are described in by Link-Local mechanisms. IPv4 methods are described in
Appendix A Appendix A
2. MUST: Listen for GRASP M_FLOOD ([I-D.ietf-anima-grasp]) 2. MUST: Listen for GRASP M_FLOOD ([I-D.ietf-anima-grasp])
announcements of the objective: "AN_Proxy". See section announcements of the objective: "AN_Proxy". See section
Section 4.1.1 for the details of the objective. The Pledge MAY Section 4.1.1 for the details of the objective. The pledge MAY
listen concurrently for other sources of information, see listen concurrently for other sources of information, see
Appendix B. Appendix B.
Once a Proxy is discovered the Pledge communicates with a Registrar Once a proxy is discovered the pledge communicates with a registrar
through the Proxy using the bootstrapping protocol defined in through the proxy using the bootstrapping protocol defined in
Section 5. Section 5.
While the GRASP M_FLOOD mechanism is passive for the Pledge, the While the GRASP M_FLOOD mechanism is passive for the pledge, the
optional other methods (mDNS, and IPv4 methods) are active. The optional other methods (mDNS, and IPv4 methods) are active. The
Pledge SHOULD run those methods in parallel with listening to for the pledge SHOULD run those methods in parallel with listening to for the
M_FLOOD. The active methods SHOULD exponentially back-off to a M_FLOOD. The active methods SHOULD exponentially back-off to a
maximum of one hour to avoid overloading the network with discovery maximum of one hour to avoid overloading the network with discovery
attempts. Detection of change of physical link status (ethernet attempts. Detection of change of physical link status (ethernet
carrier for instance) SHOULD reset the exponential back off. carrier for instance) SHOULD reset the exponential back off.
The Pledge may discover more than one proxy on a given physical The pledge could discover more than one proxy on a given physical
interface. The Pledge may have a multitude of physical interfaces as interface. The pledge can have a multitude of physical interfaces as
well: a layer-2/3 ethernet switch may have hundreds of physical well: a layer-2/3 ethernet switch may have hundreds of physical
ports. ports.
Each possible proxy offer SHOULD be attempted up to the point where a Each possible proxy offer SHOULD be attempted up to the point where a
voucher is received: while there are many ways in which the attempt voucher is received: while there are many ways in which the attempt
may fail, it does not succeed until the voucher has been validated. may fail, it does not succeed until the voucher has been validated.
The connection attempts via a single proxy SHOULD exponentially back- The connection attempts via a single proxy SHOULD exponentially back-
off to a maximum of one hour to avoid overloading the network off to a maximum of one hour to avoid overloading the network
infrastructure. The back-off timer for each MUST be independent of infrastructure. The back-off timer for each MUST be independent of
other connection attempts. other connection attempts.
Connection attempts SHOULD be run in parallel to avoid head of queue Connection attempts SHOULD be run in parallel to avoid head of queue
problems wherein an attacker running a fake Proxy or Registrar could problems wherein an attacker running a fake proxy or registrar could
perform protocol actions intentionally slowly. The Pledge SHOULD perform protocol actions intentionally slowly. The pledge SHOULD
continue to listen to for additional GRASP M_FLOOD messages during continue to listen to for additional GRASP M_FLOOD messages during
the connection attempts. the connection attempts.
Once a connection to a Registrar is established (e.g. establishment Once a connection to a registrar is established (e.g. establishment
of a TLS session key) there are expectations of more timely of a TLS session key) there are expectations of more timely
responses, see Section 5.2. responses, see Section 5.2.
Once all discovered services are attempted (assuming that none Once all discovered services are attempted (assuming that none
succeeded) the device MUST return to listening for GRASP M_FLOOD. It succeeded) the device MUST return to listening for GRASP M_FLOOD. It
SHOULD periodically retry the manufacturer specific mechanisms. The SHOULD periodically retry the manufacturer specific mechanisms. The
Pledge MAY prioritize selection order as appropriate for the pledge MAY prioritize selection order as appropriate for the
anticipated environment. anticipated environment.
4.1.1. Proxy GRASP announcements 4.1.1. Proxy GRASP announcements
A Proxy uses the DULL GRASP M_FLOOD mechanism to announce itself. A proxy uses the DULL GRASP M_FLOOD mechanism to announce itself.
This announcement can be within the same message as the ACP This announcement can be within the same message as the ACP
announcement detailed in [I-D.ietf-anima-autonomic-control-plane]. announcement detailed in [I-D.ietf-anima-autonomic-control-plane].
The M_FLOOD is formatted as follows: The M_FLOOD is formatted as follows:
[M_FLOOD, 12340815, h'fe800000000000000000000000000001', 180000, [M_FLOOD, 12340815, h'fe800000000000000000000000000001', 180000,
["AN_Proxy", 4, 1, ""], ["AN_Proxy", 4, 1, ""],
[O_IPv6_LOCATOR, [O_IPv6_LOCATOR,
h'fe800000000000000000000000000001', 'TCP', 4443]] h'fe800000000000000000000000000001', IPPROTO_TCP, 4443]]
Figure 6b: Proxy Discovery Figure 6b: Proxy Discovery
The formal CDDL definition is: The formal CDDL definition is:
flood-message = [M_FLOOD, session-id, initiator, ttl, flood-message = [M_FLOOD, session-id, initiator, ttl,
+[objective, (locator-option / [])]] +[objective, (locator-option / [])]]
objective = ["AN_Proxy", objective-flags, loop-count, objective = ["AN_Proxy", objective-flags, loop-count,
objective-value] objective-value]
skipping to change at page 33, line 28 skipping to change at page 33, line 28
locator = [ O_IPv6_LOCATOR, ipv6-address, locator = [ O_IPv6_LOCATOR, ipv6-address,
transport-proto, port-number ] transport-proto, port-number ]
ipv6-address = the v6 LL of the Proxy ipv6-address = the v6 LL of the Proxy
transport-proto = IPPROTO_TCP / IPPROTO_UDP / IPPROTO_IPV6 transport-proto = IPPROTO_TCP / IPPROTO_UDP / IPPROTO_IPV6
port-number = selected by Proxy port-number = selected by Proxy
Figure 6c: AN_Proxy CDDL Figure 6c: AN_Proxy CDDL
4.2. CoAP connection to Registrar 4.2. CoAP connection to Registrar
The use of CoAP to connect from Pledge to Registrar is out of scope The use of CoAP to connect from pledge to registrar is out of scope
for this document, and may be described in future work. for this document, and may be described in future work.
4.3. Proxy discovery of Registrar 4.3. Proxy discovery of Registrar
The Registrar SHOULD announce itself so that proxies can find it and The registrar SHOULD announce itself so that proxies can find it and
determine what kind of connections can be terminated. determine what kind of connections can be terminated.
The Registrar announces itself using ACP instance of GRASP using The registrar announces itself using ACP instance of GRASP using
M_FLOOD messages. They MUST support ANI TLS circuit Proxy and M_FLOOD messages. They MUST support ANI TLS circuit proxy and
therefore BRSKI across HTTPS/TLS native across the ACP. ANI therefore BRSKI across HTTPS/TLS native across the ACP. ANI
Registrars MAY support the IPIP proxy method by implementing IPIP registrars MAY support the IPIP proxy method by implementing IPIP
tunneling for their HTTPS/TLS traffic across the ACP. ANI Proxies tunneling for their HTTPS/TLS traffic across the ACP. ANI proxies
MUST support GRASP discovery of Registrars. MUST support GRASP discovery of registrars.
The M_FLOOD is formatted as follows: The M_FLOOD is formatted as follows:
[M_FLOOD, 12340815, h'fda379a6f6ee00000200000064000001', 180000, [M_FLOOD, 12340815, h'fda379a6f6ee00000200000064000001', 180000,
["AN_join_registrar", 4, 255, "EST-TLS"], ["AN_join_registrar", 4, 255, "EST-TLS"],
[O_IPv6_LOCATOR, [O_IPv6_LOCATOR,
h'fda379a6f6ee00000200000064000001', TCP, 80]] h'fda379a6f6ee00000200000064000001', IPPROTO_TCP, 80]]
Figure 7a: Registrar Discovery Figure 7a: Registrar Discovery
The formal CDDL definition is: The formal CDDL definition is:
flood-message = [M_FLOOD, session-id, initiator, ttl, flood-message = [M_FLOOD, session-id, initiator, ttl,
+[objective, (locator-option / [])]] +[objective, (locator-option / [])]]
objective = ["AN_join_registrar", objective-flags, loop-count, objective = ["AN_join_registrar", objective-flags, loop-count,
objective-value] objective-value]
skipping to change at page 34, line 39 skipping to change at page 34, line 39
locator3 = [O_IPv6_LOCATOR, fe80::1234, 41, nil] locator3 = [O_IPv6_LOCATOR, fe80::1234, 41, nil]
A protocol of 6 indicates that TCP proxying on the indicated port is A protocol of 6 indicates that TCP proxying on the indicated port is
desired. A protocol of 17 indicates that UDP proxying on the desired. A protocol of 17 indicates that UDP proxying on the
indicated port is desired. In each case, the traffic SHOULD be indicated port is desired. In each case, the traffic SHOULD be
proxied to the same port at the ULA address provided. proxied to the same port at the ULA address provided.
A protocol of 41 indicates that packets may be IPIP proxy'ed. In the A protocol of 41 indicates that packets may be IPIP proxy'ed. In the
case of that IPIP proxying is used, then the provided link-local case of that IPIP proxying is used, then the provided link-local
address MUST be advertised on the local link using proxy neighbour address MUST be advertised on the local link using proxy neighbour
discovery. The Join Proxy MAY limit forwarded traffic to the discovery. The proxy MAY limit forwarded traffic to the protocol (6
protocol (6 and 17) and port numbers indicated by locator1 and and 17) and port numbers indicated by locator1 and locator2. The
locator2. The address to which the IPIP traffic should be sent is address to which the IPIP traffic should be sent is the initiator
the initiator address (an ACP address of the Registrar), not the address (an ACP address of the registrar), not the address given in
address given in the locator. the locator.
Registrars MUST accept TCP / UDP traffic on the ports given at the Registrars MUST accept TCP / UDP traffic on the ports given at the
ACP address of the Registrar. If the Registrar supports IPIP ACP address of the registrar. If the registrar supports IPIP
tunnelling, it MUST also accept traffic encapsulated with IPIP. tunnelling, it MUST also accept traffic encapsulated with IPIP.
Registrars MUST accept HTTPS/EST traffic on the TCP ports indicated. Registrars MUST accept HTTPS/EST traffic on the TCP ports indicated.
Registrars MAY accept DTLS/CoAP/EST traffic on the UDP ports, in Registrars MAY accept DTLS/CoAP/EST traffic on the UDP ports, in
addition to TCP traffic. addition to TCP traffic.
5. Protocol Details (Pledge - Registrar - MASA) 5. Protocol Details (Pledge - Registrar - MASA)
The Pledge MUST initiate BRSKI after boot if it is unconfigured. The The pledge MUST initiate BRSKI after boot if it is unconfigured. The
Pledge MUST NOT automatically initiate BRSKI if it has been pledge MUST NOT automatically initiate BRSKI if it has been
configured or is in the process of being configured. configured or is in the process of being configured.
BRSKI is described as extensions to EST [RFC7030]. The goal of these BRSKI is described as extensions to EST [RFC7030]. The goal of these
extensions is to reduce the number of TLS connections and crypto extensions is to reduce the number of TLS connections and crypto
operations required on the Pledge. The Registrar implements the operations required on the pledge. The registrar implements the
BRSKI REST interface within the same "/.well-known" URI tree as the BRSKI REST interface within the same "/.well-known" URI tree as the
existing EST URIs as described in EST [RFC7030] section 3.2.2. The existing EST URIs as described in EST [RFC7030] section 3.2.2. The
communication channel between the Pledge and the Registrar is communication channel between the pledge and the registrar is
referred to as "BRSKI-EST" (see Figure 1). referred to as "BRSKI-EST" (see Figure 1).
The communication channel between the Registrar and MASA is similarly The communication channel between the registrar and MASA is similarly
described as extensions to EST within the same "/.well-known" tree. described as extensions to EST within the same "/.well-known" tree.
For clarity this channel is referred to as "BRSKI-MASA". (See For clarity this channel is referred to as "BRSKI-MASA". (See
Figure 1). Figure 1).
MASA URI is "https://" authority "/.well-known/est". MASA URI is "https://" authority "/.well-known/est".
BRSKI uses existing CMS message formats for existing EST operations. BRSKI uses existing CMS message formats for existing EST operations.
BRSKI uses JSON [RFC7159] for all new operations defined here, and BRSKI uses JSON [RFC7159] for all new operations defined here, and
voucher formats. voucher formats.
While EST section 3.2 does not insist upon use of HTTP 1.1 persistent While EST section 3.2 does not insist upon use of HTTP 1.1 persistent
connections, BRSKI-EST connections SHOULD use persistent connections. connections, BRSKI-EST connections SHOULD use persistent connections.
The intention of this guidance is to ensure the provisional TLS state The intention of this guidance is to ensure the provisional TLS state
occurs only once, and that the subsequent resolution of the provision occurs only once, and that the subsequent resolution of the provision
state is not subject to a MITM attack during a critical phase. state is not subject to a MITM attack during a critical phase.
Summarized automation extensions for the BRSKI-EST flow are: Summarized automation extensions for the BRSKI-EST flow are:
o The Pledge provisionally accepts the Registrar certificate during o The pledge provisionally accepts the registrar certificate during
the TLS handshake as detailed in Section 5.1. the TLS handshake as detailed in Section 5.1.
o In order to avoid infinite redirect loops, which a malicious o The pledge either attempts concurrent connections, or it times out
Registrar might do in order to keep the Pledge from discovering quickly and tries connections in series.
the correct Registrar, the Pledge MUST NOT follow more than one
redirection to another other web origins.
o (EST supports redirection but does not allow redirections to other
web origins without user input.)
o The Registar MAY respond with an HTTP 202 ("the request has been
accepted for processing, but the processing has not been
completed") as described in EST [RFC7030] section 4.2.3 wherein
the client "MUST wait at least the specified 'retry-after' time
before repeating the same request". The Pledge is RECOMMENDED to
provide local feedback (blinked LED etc) during this wait cycle if
mechanisms for this are available. To prevent an attacker
Registrar from significantly delaying bootstrapping the Pledge
MUST limit the 'retry-after' time to 60 seconds.
o To avoid blocking on a single erroneous Registrar the Pledge MUST
drop the connection after 5 seconds in which there has been no
progress on the TCP connection. It should proceed to connect to
any other Registrar's via any other discovered Proxies if there
are any. If there were no other Proxies discovered, the Pledge
MAY continue to wait, as long as it is concurrently listening for
new Proxy announcements.
o Ideally the Pledge could keep track of the appropriate retry-after
value for any number of outstanding Registrars but this would
involve a large state table on the Pledge. Instead the Pledge MAY
ignore the exact retry-after value in favor of a single hard coded
value that takes effect between discovery attempts. A Registrar
that is unable to complete the transaction the first time due to
timing reasons will have future chances.
o The Pledge requests and validates a voucher using the new REST o The pledge requests and validates a voucher using the new REST
calls described below. calls described below.
o If necessary the Pledge calls the EST defined /cacerts method to o The pledge completes authentication of the server certificate as
obtain the domain owners' CA certificate. The pinned-domain-
certificate element from the voucher should validate this
certificate, or be identical to it.
o The Pledge completes authentication of the server certificate as
detailed in Section 5.5.1. This moves the BRSKI-EST TLS detailed in Section 5.5.1. This moves the BRSKI-EST TLS
connection out of the provisional state. connection out of the provisional state.
o Mandatory boostrap steps conclude with Voucher Status Telemetry o Mandatory boostrap steps conclude with voucher status telemetry
(see Section 5.6). (see Section 5.6).
The BRSKI-EST TLS connection can now be used for EST enrollment. The BRSKI-EST TLS connection can now be used for EST enrollment.
The extensions for a Registrar (equivalent to EST server) are: The extensions for a registrar (equivalent to EST server) are:
o Client authentication is automated using Initial Device Identity o Client authentication is automated using Initial Device Identity
(IDevID) as per the EST certificate based client authentication. (IDevID) as per the EST certificate based client authentication.
The subject field's DN encoding MUST include the "serialNumber" The subject field's DN encoding MUST include the "serialNumber"
attribute with the device's unique serial number. attribute with the device's unique serial number.
o In the language of [RFC6125] this provides for a SERIALNUM-ID o In the language of [RFC6125] this provides for a SERIALNUM-ID
category of identifier that can be included in a certificate and category of identifier that can be included in a certificate and
therefore that can also be used for matching purposes. The therefore that can also be used for matching purposes. The
SERIALNUM-ID whitelist is collated according to manufacturer trust SERIALNUM-ID whitelist is collated according to manufacturer trust
anchor since serial numbers are not globally unique. anchor since serial numbers are not globally unique.
o The Registrar requests and validates the Voucher from the MASA. o The registrar requests and validates the voucher from the MASA.
o The Registrar forwards the Voucher to the Pledge when requested. o The registrar forwards the voucher to the pledge when requested.
o The Registar performs log verifications in addition to local o The registrar performs log verifications in addition to local
authorization checks before accepting optional Pledge device authorization checks before accepting optional pledge device
enrollment requests. enrollment requests.
5.1. BRSKI-EST TLS establishment details 5.1. BRSKI-EST TLS establishment details
The Pledge establishes the TLS connection with the Registrar through The pledge establishes the TLS connection with the registrar through
the circuit proxy (see Section 4) but the TLS handshake is with the the circuit proxy (see Section 4) but the TLS handshake is with the
Registar. The BRSKI-EST Pledge is the TLS client and the BRSKI-EST registrar. The BRSKI-EST pledge is the TLS client and the BRSKI-EST
Registrar is the TLS server. All security associations established registrar is the TLS server. All security associations established
are between the Pledge and the Registrar regardless of proxy are between the pledge and the registrar regardless of proxy
operations. operations.
Establishment of the BRSKI-EST TLS connection is as specified in EST Establishment of the BRSKI-EST TLS connection is as specified in EST
[RFC7030] section 4.1.1 "Bootstrap Distribution of CA Certificates" [RFC7030] section 4.1.1 "Bootstrap Distribution of CA Certificates"
[RFC7030] wherein the client is authenticated with the IDevID [RFC7030] wherein the client is authenticated with the IDevID
certificate, and the EST server (the Registrar) is provisionally certificate, and the EST server (the registrar) is provisionally
authenticated with an unverified server certificate. authenticated with an unverified server certificate.
The Pledge maintains a security paranoia concerning the provisional The pledge maintains a security paranoia concerning the provisional
state, and all data received, until a voucher is received and state, and all data received, until a voucher is received and
verified as specified in Section 5.5.1 verified as specified in Section 5.5.1
To avoid blocking on a single erroneous registrar the pledge MUST
drop the connection after 5 seconds in which there has been no
progress on the TCP connection. It should proceed to connect to any
other registrar's via any other discovered proxies if there are any.
If there were no other proxies discovered, the pledge MAY continue to
wait, as long as it is concurrently listening for new proxy
announcements.
5.2. Pledge Requests Voucher from the Registrar 5.2. Pledge Requests Voucher from the Registrar
When the Pledge bootstraps it makes a request for a Voucher from a When the pledge bootstraps it makes a request for a voucher from a
Registrar. registrar.
This is done with an HTTPS POST using the operation path value of This is done with an HTTPS POST using the operation path value of
"/.well-known/est/requestvoucher". "/.well-known/est/requestvoucher".
The request media types are: The request media types are:
application/voucher-cms+json The request is a "YANG-defined JSON application/voucher-cms+json The request is a "YANG-defined JSON
document that has been signed using a CMS structure" as described document that has been signed using a CMS structure" as described
in Section 3 using the JSON encoding described in [RFC7951]. The in Section 3 using the JSON encoding described in [RFC7951]. The
Pledge SHOULD sign the request using the Section 2.3 credential. pledge SHOULD sign the request using the Section 2.3 credential.
application/json The request is the "YANG-defined JSON document" as application/json The request is the "YANG-defined JSON document" as
described in Section 3 with the exception that it is not within a described in Section 3 with the exception that it is not within a
PKCS#7 structure. It is protected only by the TLS client CMS structure. It is protected only by the TLS client
authentication. This reduces the cryptographic requirements on authentication. This reduces the cryptographic requirements on
the Pledge. the pledge.
For simplicity the term 'voucher-request' is used to refer to either For simplicity the term 'voucher-request' is used to refer to either
of these media types. Registrar impementations SHOULD anticipate of these media types. Registrar impementations SHOULD anticipate
future media types but of course will simply fail the request if future media types but of course will simply fail the request if
those types are not yet known. those types are not yet known.
The Pledge populates the voucher-request fields as follows: The pledge populates the voucher-request fields as follows:
created-on: Pledges that have a realtime clock are RECOMMENDED to created-on: Pledges that have a realtime clock are RECOMMENDED to
populate this field. This provides additional information to the populate this field. This provides additional information to the
MASA. MASA.
nonce: The Pledge voucher-request MUST contain a cryptographically nonce: The pledge voucher-request MUST contain a cryptographically
strong random or pseudo-random number nonce. Doing so ensures strong random or pseudo-random number nonce. Doing so ensures
Section 2.6.1 functionality. The nonce MUST NOT be reused for Section 2.6.1 functionality. The nonce MUST NOT be reused for
multiple bootstrapping attempts. multiple bootstrapping attempts.
assertion: The Pledge voucher-request MAY contain an assertion of assertion: The pledge voucher-request MAY contain an assertion of
"proximity". "proximity".
proximity-registrar-cert: In a Pledge voucher-request this is the proximity-registrar-cert: In a pledge voucher-request this is the
first certificate in the TLS server 'certificate_list' sequence first certificate in the TLS server 'certificate_list' sequence
(see [RFC5246]) presented by the Registrar to the Pledge. This (see [RFC5246]) presented by the registrar to the pledge. This
MUST be populated in a Pledge voucher-request if the "proximity" MUST be populated in a pledge voucher-request if the "proximity"
assertion is populated. assertion is populated.
All other fields MAY be omitted in the Pledge voucher-request. All other fields MAY be omitted in the pledge voucher-request.
An example JSON payload of a Pledge voucher-request is in Section 3.2 An example JSON payload of a pledge voucher-request is in Section 3.2
Example 1. Example 1.
The Registrar validates the client identity as described in EST The registrar validates the client identity as described in EST
[RFC7030] section 3.3.2. If the request is signed the Registrar [RFC7030] section 3.3.2. If the request is signed the registrar
confirms that the 'proximity' asserion and associated 'proximity- confirms that the 'proximity' asserion and associated 'proximity-
registrar-cert' are correct. The Registrar performs authorization as registrar-cert' are correct. The registrar performs authorization as
detailed in [[EDNOTE: UNRESOLVED. See Appendix D "Pledge detailed in [[EDNOTE: UNRESOLVED. See Appendix D "Pledge
Authorization"]]. If these validations fail the Registrar SHOULD Authorization"]]. If these validations fail the registrar SHOULD
respond with an appropriate HTTP error code. respond with an appropriate HTTP error code.
If authorization is successful the Registrar obtains a voucher from If authorization is successful the registrar obtains a voucher from
the MASA service (see Section 5.4) and returns that MASA signed the MASA service (see Section 5.4) and returns that MASA signed
voucher to the Pledge as described in Section 5.5. voucher to the pledge as described in Section 5.5.
5.3. BRSKI-MASA TLS establishment details 5.3. BRSKI-MASA TLS establishment details
The BRSKI-MASA TLS connection is a 'normal' TLS connection The BRSKI-MASA TLS connection is a 'normal' TLS connection
appropriate for HTTPS REST interfaces. The Registrar initiates the appropriate for HTTPS REST interfaces. The registrar initiates the
connection and uses the MASA URL obtained as described in Section 2.8 connection and uses the MASA URL obtained as described in Section 2.8
for [RFC6125] authentication of the MASA server. for [RFC6125] authentication of the MASA server.
The primary method of Registrar "authentication" by the MASA is The primary method of registrar "authentication" by the MASA is
detailed in Section 5.4. As detailed in Section 9 the MASA might detailed in Section 5.4. As detailed in Section 9 the MASA might
find it necessary to request additional Registrar authentication. find it necessary to request additional registrar authentication.
Registrars MUST be prepared to support TLS client certificate
authentication and HTTP Basic or Digest authentication as described The MASA and the registrars SHOULD be prepared to support TLS client
in RFC7030 for EST clients. Implementors are advised that contacting certificate authentication and/or HTTP Basic or Digest authentication
the MASA is to establish a secured REST connection with a web service as described in RFC7030 for EST clients. This connection MAY also
and that there are a number of authentication models being explored have no client authentication at all (Section 6.4)
within the industry. Registrars are RECOMMENDED to fail gracefully
and generate useful administrative notifications or logs in the The authentication of the BRSKI-MASA connection does not affect the
advent of unexpected HTTP 401 (Unauthorized) responses from the MASA. voucher-request process, as voucher-requests are already signed by
the registrar. Instead, this authentication provides access control
to the audit log.
Implementors are advised that contacting the MASA is to establish a
secured REST connection with a web service and that there are a
number of authentication models being explored within the industry.
Registrars are RECOMMENDED to fail gracefully and generate useful
administrative notifications or logs in the advent of unexpected HTTP
401 (Unauthorized) responses from the MASA.
5.4. Registrar Requests Voucher from MASA 5.4. Registrar Requests Voucher from MASA
When a Registrar receives a Pledge voucher-request it in turn submits When a registrar receives a pledge voucher-request it in turn submits
a Registrar voucher-request to the MASA service. For simplicity this a registrar voucher-request to the MASA service via an HTTPS RESTful
is defined as an optional EST message between a Registrar and an EST interface ([RFC7231]).
server running on the MASA service although the Registrar is not
required to make use of any other EST functionality when
communicating with the MASA service. (The MASA service MUST properly
reject any EST functionality requests it does not wish to service; a
requirement that holds for any REST interface).
This is done with an HTTP POST using the operation path value of This is done with an HTTP POST using the operation path value of
"/.well-known/est/requestvoucher". "/.well-known/est/requestvoucher".
The request media type is defined in [I-D.ietf-anima-voucher] and is The request media type is defined in [I-D.ietf-anima-voucher] and is
application/voucher-cms+json. It is a JSON document that has been application/voucher-cms+json. It is a JSON document that has been
signed using a CMS structure. The Registrar MUST sign the Registrar signed using a CMS structure. The registrar MUST sign the registrar
voucher-request. The entire Registrar certificate chain, up to and voucher-request. The entire registrar certificate chain, up to and
including the Domain CA, MUST be included in the PKCS#7 structure. including the Domain CA, MUST be included in the CMS structure.
MASA impementations SHOULD anticipate future media types but of MASA impementations SHOULD anticipate future media types but of
course will simply fail the request if those types are not yet known. course will simply fail the request if those types are not yet known.
The Registrar populates the voucher-request fields as follows: The registrar populates the voucher-request fields as follows:
created-on: Registrars are RECOMMENDED to populate this field. This created-on: Registrars are RECOMMENDED to populate this field. This
provides additional information to the MASA. provides additional information to the MASA.
nonce: The optional nonce value from the Pledge request if desired nonce: The optional nonce value from the pledge request if desired
(see below). (see below).
serial-number: The serial number of the Pledge the Registrar would serial-number: The serial number of the pledge the registrar would
like a voucher for. The Registrar determines this value by like a voucher for. The registrar determines this value by
parsing the authenticated Pledge IDevID certificate. See parsing the authenticated pledge IDevID certificate. See
Section 2.3. The Registrar SHOULD verify that the serial number Section 2.3. The registrar SHOULD verify that the serial number
field it parsed matches the serial number field the Pledge field it parsed matches the serial number field the pledge
provided in its voucher-request. This provides a sanity check provided in its voucher-request. This provides a sanity check
useful for detecting error conditions and logging. The Registrar useful for detecting error conditions and logging. The registrar
MUST NOT simply copy the serial number field from a Pledge voucher MUST NOT simply copy the serial number field from a pledge voucher
request as that field is claimed but not certified. request as that field is claimed but not certified.
idevid-issuer: The idevid-issuer value from the Pledge certificate idevid-issuer: The idevid-issuer value from the pledge certificate
is included to ensure a statistically unique identity. is included to ensure a statistically unique identity.
prior-signed-voucher: If a signed Pledge voucher-request was prior-signed-voucher-request: If a signed pledge voucher-request was
received then it SHOULD be included in the Registrar voucher- received then it SHOULD be included in the registrar voucher-
request. (NOTE: what is included is the complete Pledge voucher- request. (NOTE: what is included is the complete pledge voucher-
request, inclusive of the 'assertion', 'proximity-registrar-cert', request, inclusive of the 'assertion', 'proximity-registrar-cert',
etc wrapped by the Pledge's original signature). If a signed etc wrapped by the pledge's original signature). If a signed
voucher-request was not recieved from the Pledge then this leaf is voucher-request was not recieved from the pledge then this leaf is
omitted from the Registrar voucher request. omitted from the registrar voucher request.
A nonceless Registrar voucher-request MAY be submitted to the MASA. A nonceless registrar voucher-request MAY be submitted to the MASA.
Doing so allows the Registrar to request a Voucher when the Pledge is Doing so allows the registrar to request a voucher when the pledge is
offline, or when the Registrar is expected to be offline when the offline, or when the registrar anticipates not being able to connect
Pledge is being deployed. These use cases require the Registrar to to the MASA while the pledge is being deployed. Some use cases
learn the appropriate IDevID SerialNumber field from the physical require the registrar to learn the appropriate IDevID SerialNumber
device labeling or from the sales channel (out-of-scope for this field from the physical device labeling or from the sales channel
document). If a nonceless voucher-reqeust is submitted the MASA (out-of-scope for this document).
server MUST authenticate the Registrar as described in either EST
[RFC7030] section 3.2, section 3.3, or by validating the Registrar's
certificate used to sign the Registrar voucher-request. Any of these
methods reduce the risk of DDoS attacks and provide an authenticated
identity as an input to sales channel integration and authorizations
(the actual sale-channel integration is also out-of-scope of this
document).
All other fields MAY be omitted in the Registrar voucher-request. All other fields MAY be omitted in the registrar voucher-request.
Example JSON payloads of Registrar voucher-requests are in Example JSON payloads of registrar voucher-requests are in
Section 3.2 Examples 2 through 4. Section 3.2 Examples 2 through 4.
The MASA verifies that the Registrar voucher-request is internally The MASA verifies that the registrar voucher-request is internally
consistent but does not necessarily authenticate the Registrar consistent but does not necessarily authenticate the registrar
certificate since the Registrar is not known to the MASA server in certificate since the registrar is not known to the MASA server in
advance. The MASA performs the following actions and validation advance. The MASA performs the actions and validation checks
checks before issuing a voucher: described in the following sub-sections before issuing a voucher.
5.4.1. Renew for expired voucher 5.4.1. MASA renewal of expired vouchers
As described in [I-D.ietf-anima-voucher] vouchers are normally short As described in [I-D.ietf-anima-voucher] vouchers are normally short
lived to avoid revocation issues. If the request is for a previous lived to avoid revocation issues. If the request is for a previous
(expired) voucher using the same Registrar (as determined by the (expired) voucher using the same registrar (as determined by the
Registrar pinned-domain-cert) and the MASA has not been informed that registrar pinned-domain-cert) and the MASA has not been informed that
the claim is invalid then the request for a renewed voucher SHOULD be the claim is invalid then the request for a renewed voucher SHOULD be
automatically authorized. automatically authorized.
5.4.2. Voucher signature consistency 5.4.2. MASA verification of voucher-request signature consistency
The MASA MUST verify that the Registrar voucher-request is signed by The MASA MUST verify that the registrar voucher-request is signed by
a Registrar. This is confirmed by verifying that the id-kp-cmcRA a registrar. This is confirmed by verifying that the id-kp-cmcRA
extended key usage extension field (as detailed in EST RFC7030 extended key usage extension field (as detailed in EST RFC7030
section 3.6.1) exists in the certificate of the entity that signed section 3.6.1) exists in the certificate of the entity that signed
the Registrar voucher-request. This verification is only a the registrar voucher-request. This verification is only a
consistency check that the unauthenticated domain CA intended this to consistency check that the unauthenticated domain CA intended the
be a Registrar. Performing this check provides value to domain PKI voucher-request signer to be a registrar. Performing this check
by assuring the domain administrator that the MASA service will only provides value to the domain PKI by assuring the domain administrator
respect claims from authorized Registration Authorities of the that the MASA service will only respect claims from authorized
domain. (The requirement for the Registrar to include the Domain CA Registration Authorities of the domain.
certificate in the signature structure was stated above.)
5.4.3. Registrar revocation consistency The MASA verifies that the domain CA certificate is included in the
CMS structure as detailed in Section 5.4.
If the Registrar uses a CA known to the MASA, and it makes 5.4.3. MASA authentication of registrar (certificate)
certificate revocation information available to the MASA, then the
MASA SHOULD check for the maximum validity of the Registrar's If a nonceless voucher-request is submitted the MASA server MUST
certificate. authenticate the registrar as described in either EST [RFC7030]
section 3.2, section 3.3, or by validating the registrar's
certificate used to sign the registrar voucher-request. Any of these
methods reduce the risk of DDoS attacks and provide an authenticated
identity as an input to sales channel integration and authorizations
(the actual sale-channel integration is also out-of-scope of this
document).
In the nonced case, validation of the registrar MAY be omitted if the
device policy is to accept audit-only vouchers.
5.4.4. MASA revocation checking of registrar (certificate)
Note that this section is about ensuring consistency of the
registrar. These checks are not equivalent to [RFC5280] Certificate
Revocation Checks that the pledge would ideally do if it had a real
time clock.
If the registrar uses a CA for which the MASA is able to obtain
revocation information, then the MASA SHOULD check for the maximum
validity period of the registrar's certificate.
A registrar which has done these checks may set the "domain-cert-
revocation-checks" attribute in the voucher to false (or omit it).
There are three times to consider: a) a configured voucher lifetime There are three times to consider: a) a configured voucher lifetime
in the MASA, b) the expiry time for the Registrar's Certificate, c) in the MASA, b) the expiry time for the registrar's certificate, c)
any certificate revocation information (CRL) lifetime. any certificate revocation information (CRL) lifetime.
The resulting voucher should have a lifetime (expires-on field) which The resulting voucher should have a lifetime (expires-on field) which
is the earliest of these three values. Typically (b) will be some is the earliest of these three values. Typically (b) will be some
significant time in the future, but (c) will typically be short (on significant time in the future, but (c) will typically be short (on
the order of a week or less). The RECOMMENDED period for (a) is on the order of a week or less). The RECOMMENDED period for (a) is on
the order of 20 minutes, so it will typically determine the lifespan the order of 20 minutes, so it will typically determine the lifespan
of the resulting voucher. of the resulting voucher.
By limiting the voucher lifetime in this way, the MASA is effectively By limiting the voucher lifetime in this way, the MASA is ensuring
doing CRL and lifetime checks on behalf of the Pledge. While the the voucher is consistent with any CRL and lifetime checks. See
pledge may be without a real time clock to tell it absolute time, it section Section 2.6.1.
SHOULD be able to calculate relative time. See section
Section 2.6.1.
If CRL information is unavailable to the MASA, then the MASA SHOULD If CRL information is unavailable to the MASA, then the MASA SHOULD
rely on the validity information Because the Registar certificate rely on the validity information Because the registrar certificate
authority is unknown to the MASA in advance this is only an extended authority is unknown to the MASA in advance this is only an extended
consistency check and is not required. The maximum lifetime of the consistency check and is not required. The maximum lifetime of the
voucher issued SHOULD NOT exceed the lifetime of the Registrar's voucher issued SHOULD NOT exceed the lifetime of the registrar's
revocation validation (for example if the Registrar revocation status revocation validation (for example if the registrar revocation status
is indicated in a CRL that is valid for two weeks then that is an is indicated in a CRL that is valid for two weeks then that is an
appropriate lifetime for the voucher.) appropriate lifetime for the voucher.)
5.4.4. Pledge proximity assertion 5.4.5. MASA verification of pledge prior-signed-voucher-request
The MASA server MAY verify that the Registrar voucher-request
includes the 'prior-signed-voucher' field populated with a Pledge
voucher-request that includes a 'proximity-registrar-cert' that is
consistent with the certificate used to sign the Registrar voucher-
request. The MASA server is aware of which Pledges support signing
of their voucher requests and can use this information to confirm
proximity of the Pledge with the Registrar.
5.4.5. Registar (certificate) authentication The MASA server MAY verify that the registrar voucher-request
includes the 'prior-signed-voucher-request' field populated with a
signed pledge voucher-request that includes a 'proximity-registrar-
cert' that is consistent with the certificate used to sign the
registrar voucher-request. This ensures that the BRSKI-EST TLS
connection has no man-in-the-middle. The MASA server is aware of
which pledges support signing of their voucher requests and can use
this information to confirm proximity of the pledge with the
registrar.
The pledge proximity assertion only occurs if the Registrar voucher- If this check succeeds the MASA updates the voucher and audit log
request is nonceless. As noted above the details concerning assertion leafs with the "proximity" assertion.
necessary sales-channel integration for the MASA to authenticate a
Registrar certificate is out-of-scope.
5.4.6. Registrar Anchor 5.4.6. MASA pinning of registrar
The Registrar's certificate chain is extracted from the signature The registrar's certificate chain is extracted from the signature
method and the root certificate is used to populate the "pinned- method. The chain includes the domain CA certificate as specified in
domain-cert" of the Voucher being issued. The domainID (e.g., hash Section 5.4. This certificate is used to populate the "pinned-
domain-cert" of the voucher being issued. The domainID (e.g., hash
of the root public key) is determined from the pinned-domain-cert and of the root public key) is determined from the pinned-domain-cert and
is used to update the audit log. is used to update the audit log.
5.5. Voucher Response 5.4.7. MASA nonce handling
The voucher response to requests from the Pledge and requests from a The MASA does not verify the nonce itself. It MAY perform a simple
Registrar are in the same format. A Registrar either caches prior consistency check: If the registrar voucher-request contains a nonce
MASA responses or dynamically requests a new Voucher based on local and the prior-signed-voucher-request exists then the nonce in both
MUST be consistent. (Recall from above that the voucher-request
might not contain a nonce, see Section 5.4 and Section 5.4.3).
The MASA MUST use the nonce from the registrar voucher-request for
the resulting voucher and audit log. The prior-signed-voucher-
request nonce is ignored during this operation.
5.5. MASA Voucher Response
The voucher response to requests from the pledge and requests from a
registrar are in the same format. A registrar either caches prior
MASA responses or dynamically requests a new voucher based on local
policy. policy.
If the join operation is successful, the server (MASA responding to If the join operation is successful, the server (MASA responding to
Registrar, and Registrar responding to Pledge) response MUST contain registrar, and registrar responding to pledge) response MUST contain
an HTTP 200 response code. The server MUST answer with a suitable an HTTP 200 response code. The server MUST answer with a suitable
4xx or 5xx HTTP [RFC2616] error code when a problem occurs. In this 4xx or 5xx HTTP [RFC2616] error code when a problem occurs. In this
case, the response data from the MASA server MUST be a plaintext case, the response data from the MASA server MUST be a plaintext
human-readable (ASCII, English) error message containing explanatory human-readable (ASCII, English) error message containing explanatory
information describing why the request was rejected. information describing why the request was rejected.
The registrar MAY respond with an HTTP 202 ("the request has been
accepted for processing, but the processing has not been completed")
as described in EST [RFC7030] section 4.2.3 wherein the client "MUST
wait at least the specified 'Retry-After' time before repeating the
same request". (see [RFC7231] section 6.6.4) The pledge is
RECOMMENDED to provide local feedback (blinked LED etc) during this
wait cycle if mechanisms for this are available. To prevent an
attacker registrar from significantly delaying bootstrapping the
pledge MUST limit the 'Retry-After' time to 60 seconds. Ideally the
pledge would keep track of the appropriate Retry-After header values
for any number of outstanding registrars but this would involve a
state table on the pledge. Instead the pledge MAY ignore the exact
Retry-After value in favor of a single hard coded value. A registrar
that is unable to complete the transaction the first time due to
timing reasons will have future chances.
In order to avoid infinite redirect loops, which a malicious
registrar might do in order to keep the pledge from discovering the
correct registrar, the pledge MUST NOT follow more than one
redirection (3xx code) to another web origins. EST supports
redirection but requires user input; this change allows the pledge to
follow a single redirection without a user interaction.
A 403 (Forbidden) response is appropriate if the voucher-request is A 403 (Forbidden) response is appropriate if the voucher-request is
not signed correctly, stale, or if the Pledge has another outstanding not signed correctly, stale, or if the pledge has another outstanding
voucher that cannot be overridden. voucher that cannot be overridden.
A 404 (Not Found) response is appropriate when the request is for a A 404 (Not Found) response is appropriate when the request is for a
device that is not known to the MASA. device that is not known to the MASA.
A 406 (Not Acceptable) response is appropriate if a voucher of the A 406 (Not Acceptable) response is appropriate if a voucher of the
desired type, or using the desired algorithms (as indicated by the desired type, or using the desired algorithms (as indicated by the
Accept: headers, and algorithms used in the signature) cannot be Accept: headers, and algorithms used in the signature) cannot be
issued, such as because the MASA knows the Pledge cannot process that issued, such as because the MASA knows the pledge cannot process that
type. type.
A 415 (Unsupported Media Type) response is approriate for a request A 415 (Unsupported Media Type) response is approriate for a request
that has a voucher encoding that is not understood. that has a voucher encoding that is not understood.
The response media type is: The response media type is:
application/voucher-cms+json The response is a "YANG-defined JSON application/voucher-cms+json The response is a "YANG-defined JSON
document that has been signed using a CMS structure" as described document that has been signed using a CMS structure" as described
in [I-D.ietf-anima-voucher] using the JSON encoded described in in [I-D.ietf-anima-voucher] using the JSON encoded described in
skipping to change at page 43, line 43 skipping to change at page 44, line 22
{ {
"ietf-voucher:voucher": { "ietf-voucher:voucher": {
"nonce": "62a2e7693d82fcda2624de58fb6722e5", "nonce": "62a2e7693d82fcda2624de58fb6722e5",
"assertion": "logging" "assertion": "logging"
"pinned-domain-cert": "base64encodedvalue==" "pinned-domain-cert": "base64encodedvalue=="
"serial-number": "JADA123456789" "serial-number": "JADA123456789"
} }
} }
The Pledge verifies the signed voucher using the manufacturer 5.5.1. Pledge voucher verification
installed trust anchor associated with the manufacturer's selected
Manufacturer Authorized Signing Authority.
The Pledge verifies the serial-number field of the signed voucher The pledge MUST verify the voucher signature using the manufacturer
matches the Pledge's serial-number. installed trust anchor associated with the manufacturer's MASA (this
is likely included in the pledge's firmware).
The 'pinned-domain-cert' element of the voucher contains the domain The pledge MUST verify the serial-number field of the signed voucher
CA's public key. The Pledge MUST use the 'pinned-domain-cert' trust matches the pledge's own serial-number.
anchor to immediately complete authentication of the provisional TLS
connection.
The Pledge MUST be prepared to parse and fail gracefully from a The pledge MUST verify that the voucher nonce field is accurate and
Voucher response that does not contain a 'pinned-domain-cert' field. matches the nonce the pledge submitted to this registrar, or that the
The Pledge MUST be prepared to ignore additional fields that it does voucher is nonceless (see Section 6.2).
The pledge MUST be prepared to parse and fail gracefully from a
voucher response that does not contain a 'pinned-domain-cert' field.
The pledge MUST be prepared to ignore additional fields that it does
not recognize. not recognize.
5.5.1. Completing authentication of Provisional TLS connection 5.5.2. Pledge authentication of provisional TLS connection
If a Registrar's credentials cannot be verified using the pinned- The 'pinned-domain-cert' element of the voucher contains the domain
CA's public key. The pledge MUST use the 'pinned-domain-cert' trust
anchor to immediately complete authentication of the provisional TLS
connection.
If a registrar's credentials cannot be verified using the pinned-
domain-cert trust anchor from the voucher then the TLS connection is domain-cert trust anchor from the voucher then the TLS connection is
immediately discarded and the Pledge abandons attempts to bootstrap immediately discarded and the pledge abandons attempts to bootstrap
with this discovered Registrar. The Pledge SHOULD send voucher with this discovered registrar. The pledge SHOULD send voucher
status telemetry (described below) before closing the TLS connection. status telemetry (described below) before closing the TLS connection.
The Pledge MUST attempt to enroll using any other proxies it has The pledge MUST attempt to enroll using any other proxies it has
found. It SHOULD return to the same proxy again after attempting found. It SHOULD return to the same proxy again after attempting
with other proxies. Attempts should be attempted in the exponential with other proxies. Attempts should be attempted in the exponential
backoff described earlier. Attempts SHOULD be repeated as failure backoff described earlier. Attempts SHOULD be repeated as failure
may be the result of a temporary inconsistently (an inconsistently may be the result of a temporary inconsistently (an inconsistently
rolled Registrar key, or some other mis-configuration.) The rolled registrar key, or some other mis-configuration). The
inconsistently could also be the result an active MITM attack on the inconsistently could also be the result an active MITM attack on the
EST connection. EST connection.
The Registrar MUST use a certificate that chains to the pinned- The registrar MUST use a certificate that chains to the pinned-
domain-cert as its TLS server certificate. domain-cert as its TLS server certificate.
The Pledge's PKIX path validation of a Registrar certificate's The pledge's PKIX path validation of a registrar certificate's
validity period information is as described in Section 2.6.1. Once validity period information is as described in Section 2.6.1. Once
the PKIX path validation is successful the TLS connection is no the PKIX path validation is successful the TLS connection is no
longer provisional. longer provisional.
The pinned-domain-cert is installed as an Explicit Trust Anchor for The pinned-domain-cert MAY be installed as an trust anchor for future
future operations. It can therefore can be used to authenticate any operations. It can therefore can be used to authenticate any
dynamically discovered EST server that contain the id-kp-cmcRA dynamically discovered EST server that contain the id-kp-cmcRA
extended key usage extension as detailed in EST RFC7030 section extended key usage extension as detailed in EST RFC7030 section
3.6.1; but to reduce system complexity the Pledge SHOULD avoid 3.6.1; but to reduce system complexity the pledge SHOULD avoid
additional discovery operations. Instead the Pledge SHOULD additional discovery operations. Instead the pledge SHOULD
communicate directly with the Registrar as the EST server. The communicate directly with the registrar as the EST server. The
'pinned-domain-cert' is not a complete distribution of the [RFC7030] 'pinned-domain-cert' is not a complete distribution of the [RFC7030]
section 4.1.3 CA Certificate Response, which is an additional section 4.1.3 CA Certificate Response, which is an additional
justification for the recommendation to proceed with EST key justification for the recommendation to proceed with EST key
management operations. Once a full CA Certificate Response is management operations. Once a full CA Certificate Response is
obtained it is more authoritative for the domain than the limited obtained it is more authoritative for the domain than the limited
'pinned-domain-cert' response. 'pinned-domain-cert' response.
5.6. Voucher Status Telemetry 5.6. Pledge Voucher Status Telemetry
The domain is expected to provide indications to the system The domain is expected to provide indications to the system
administrators concerning device lifecycle status. To facilitate administrators concerning device lifecycle status. To facilitate
this it needs telemetry information concerning the device's status. this it needs telemetry information concerning the device's status.
To indicate Pledge status regarding the Voucher, the Pledge MUST post To indicate pledge status regarding the voucher, the pledge MUST post
a status message. a status message.
The posted data media type: application/json The posted data media type: application/json
The client HTTP POSTs the following to the server at the EST well The client HTTP POSTs the following to the server at the EST well
known URI "/voucher_status". The Status field indicates if the known URI "/voucher_status". The Status field indicates if the
Voucher was acceptable. If it was not acceptable the Reason string voucher was acceptable. If it was not acceptable the Reason string
indicates why. In the failure case this message may be sent to an indicates why. In the failure case this message may be sent to an
unauthenticated, potentially malicious Registrar and therefore the unauthenticated, potentially malicious registrar and therefore the
Reason string SHOULD NOT provide information beneficial to an Reason string SHOULD NOT provide information beneficial to an
attacker. The operational benefit of this telemetry information is attacker. The operational benefit of this telemetry information is
balanced against the operational costs of not recording that an balanced against the operational costs of not recording that an
Voucher was ignored by a client the registar expected to continue voucher was ignored by a client the registrar expected to continue
joining the domain. joining the domain.
{ {
"version":"1", "version":"1",
"Status":FALSE /* TRUE=Success, FALSE=Fail" "Status":FALSE /* TRUE=Success, FALSE=Fail"
"Reason":"Informative human readable message" "Reason":"Informative human readable message"
"reason-context": { additional JSON } "reason-context": { additional JSON }
} }
The server SHOULD respond with an HTTP 200 but MAY simply fail with The server SHOULD respond with an HTTP 200 but MAY simply fail with
an HTTP 404 error. The client ignores any response. Within the an HTTP 404 error. The client ignores any response. Within the
server logs the server SHOULD capture this telemetry information. server logs the server SHOULD capture this telemetry information.
The reason-context attribute is an arbitrary JSON object (literal The reason-context attribute is an arbitrary JSON object (literal
value or hash of values) which provides additional information value or hash of values) which provides additional information
specific to this Pledge. The contents of this field are not subject specific to this pledge. The contents of this field are not subject
to standardization. to standardization.
Additional standard responses MAY be added via Specification Additional standard responses MAY be added via Specification
Required. Required.
5.7. MASA authorization log Request 5.7. Registrar audit log request
After receiving the voucher status telemetry Section 5.6, the After receiving the voucher status telemetry Section 5.6, the
Registrar SHOULD request the MASA authorization log from the MASA registrar SHOULD request the MASA audit log from the MASA service.
service using this EST extension. If a device had previously
registered with another domain, a Registrar of that domain would show
in the log.
This is done with an HTTP GET using the operation path value of This is done with an HTTP GET using the operation path value of
"/.well-known/est/requestauditlog". "/.well-known/est/requestauditlog".
The Registrar MUST HTTP POST the same Registrar voucher-request as it The registrar SHOULD HTTP POST the same registrar voucher-request as
did when requesting a Voucher. It is posted to the /requestauditlog it did when requesting a voucher. It is posted to the
URI instead. The "idevid-issuer" and "serial-number" informs the /requestauditlog URI instead. The "idevid-issuer" and "serial-
MASA server which log is requested so the appropriate log can be number" informs the MASA server which log is requested so the
prepared for the response. Using the same media type and message appropriate log can be prepared for the response. Using the same
minimizes cryptographic and message operations although it results in media type and message minimizes cryptographic and message operations
additional network traffic. The relying MASA server implementation although it results in additional network traffic. The relying MASA
MAY leverage internal state to associate this request with the server implementation MAY leverage internal state to associate this
original, and by now already validated, Registrar voucher-request so request with the original, and by now already validated, voucher-
as to avoid an extra crypto validation. request so as to avoid an extra crypto validation.
A registrar MAY request logs at future times. If the registrar
generates a new request then the MASA is forced to perform the
additional cryptographic operations to verify the new request.
A MASA that receives a request for a device that does not exist, or A MASA that receives a request for a device that does not exist, or
for which the requesting owner was never an owner returns an HTTP 404 for which the requesting owner was never an owner returns an HTTP 404
("Not found") code. ("Not found") code.
Rather than returning the audit log as a response to the POST (with a Rather than returning the audit log as a response to the POST (with a
return code 200), the MASA MAY instead return a 201 ("Created") return code 200), the MASA MAY instead return a 201 ("Created")
RESTful response ([RFC7231] section 7.1) containing a URL to the RESTful response ([RFC7231] section 7.1) containing a URL to the
prepared (and easily cachable) audit response. prepared (and easily cachable) audit response.
In order to avoid enumeration of device audit logs, MASA servers that In order to avoid enumeration of device audit logs, MASA servers that
return URLs SHOULD take care to make the returned URL unguessable. return URLs SHOULD take care to make the returned URL unguessable.
For instance, rather than returning URLs containing a database number For instance, rather than returning URLs containing a database number
such as https://example.com/auditlog/1234 or the EUI of the device such as https://example.com/auditlog/1234 or the EUI of the device
such https://example.com/auditlog/10-00-00-11-22-33, the MASA SHOULD such https://example.com/auditlog/10-00-00-11-22-33, the MASA SHOULD
return a randomly generated value (a "slug" in web parlance). The return a randomly generated value (a "slug" in web parlance). The
value is used to find the relevant database entry. value is used to find the relevant database entry.
A MASA that returns a code 200 MAY also include a Location: header A MASA that returns a code 200 MAY also include a Location: header
for future reference by the Registrar. for future reference by the registrar.
The request media type is: The request media type is:
application/voucher-cms+json The request is a "YANG-defined JSON application/voucher-cms+json The request is a "YANG-defined JSON
document that has been signed using a CMS structure" as described document that has been signed using a CMS structure" as described
in Section 3 using the JSON encoded described in [RFC7951]. The in Section 3 using the JSON encoded described in [RFC7951]. The
Registrar MUST sign the request. The entire Registrar certificate registrar MUST sign the request. The entire registrar certificate
chain, up to and including the Domain CA, MUST be included in the chain, up to and including the Domain CA, MUST be included in the
CMS structure. CMS structure.
5.7.1. MASA authorization log Response 5.7.1. MASA audit log response
A log data file is returned consisting of all log entries. For
example:
{
"version":"1",
"events":[
{
"date":"<date/time of the entry>",
"domainID":"<domainID extracted from voucher-request>",
"nonce":"<any nonce if supplied (or the exact string 'NULL')>"
},
{
"date":"<date/time of the entry>",
"domainID":"<domainID extracted from voucher-request>",
"nonce":"<any nonce if supplied (or the exact string 'NULL')>"
}
],
"truncation": {
"nonced duplicates": <number of entries truncated>,
"nonceless duplicates": <number of entries truncated>,
"arbitrary": <number of entries trucated>
}
}
A Registrar SHOULD use this log information to make an informed A log data file is returned consisting of all log entries. The
decision regarding the continued bootstrapping of the Pledge. For returned data is in JSON format ([RFC7951]), and the Content-Type
example if the log includes an unexpected domainID then the Pledge SHOULD be "application/json". For example:
could have imprinted on an unexpected domain. If the log includes
nonceless entries then any Registrar in the same domain could
theoretically trigger a reset of the device and take over management
of the Pledge. Equipment that is purchased pre-owned can be expected
to have an extensive history. A Registrar MAY request logs at future
times. A Registrar MAY be configured to ignore the history of the
device but it is RECOMMENDED that this only be configured if hardware
assisted NEA [RFC5209] is supported.
Log entries can be compared against local history logs in search of {
discrepancies. "version":"1",
"events":[
{
"date":"<date/time of the entry>",
"domainID":"<domainID extracted from voucher-request>",
"nonce":"<any nonce if supplied (or the exact string 'NULL')>"
"assertion":"<the value that was placed in the voucher assertion leaf>"
},
{
"date":"<date/time of the entry>",
"domainID":"<anotherDomainID extracted from voucher-request>",
"nonce":"<any nonce if supplied (or the exact string 'NULL')>"
"assertion":"<the value that was placed in the voucher assertion leaf>"
}
],
"truncation": {
"nonced duplicates": <number of entries truncated>,
"nonceless duplicates": <number of entries truncated>,
"arbitrary": <number of entries trucated>
}
}
Distribution of a large log is less than ideal. This structure can Distribution of a large log is less than ideal. This structure can
be optimized as follows: Nonced or Nonceless entries for the same be optimized as follows: Nonced or Nonceless entries for the same
domainID MAY be truncated from the log leaving only the single most domainID MAY be truncated from the log leaving only the single most
recent nonced or nonceless entry. The log SHOULD NOT be further recent nonced or nonceless entry. The log SHOULD NOT be further
reduced but there could exist operational situation where maintaining reduced but there could exist operational situation where maintaining
the full log is not possible. In such situations the log MAY be the full log is not possible. In such situations the log MAY be
arbitrarily truncated for length. The trunctation method(s) used arbitrarily truncated for length. The trunctation method(s) used
MUST be indicated in the JSON truncation dictionary using "nonced MUST be indicated in the JSON truncation dictionary using "nonced
duplicates", "nonceless duplicates", and "arbitrary" where the number duplicates", "nonceless duplicates", and "arbitrary" where the number
skipping to change at page 48, line 12 skipping to change at page 48, line 48
count exceeds 1024 then the MASA MAY use this value without further count exceeds 1024 then the MASA MAY use this value without further
incrementing it. incrementing it.
A log where duplicate entries for the same domain have been truncated A log where duplicate entries for the same domain have been truncated
("nonced duplicates" and/or "nonceless duplicates) could still be ("nonced duplicates" and/or "nonceless duplicates) could still be
acceptable for informed decisions. A log that has had "arbitrary" acceptable for informed decisions. A log that has had "arbitrary"
truncations is less acceptable but manufacturer transparency is truncations is less acceptable but manufacturer transparency is
better than hidden truncations. better than hidden truncations.
This document specifies a simple log format as provided by the MASA This document specifies a simple log format as provided by the MASA
service to the registar. This format could be improved by service to the registrar. This format could be improved by
distributed consensus technologies that integrate vouchers with distributed consensus technologies that integrate vouchers with
technologies such as block-chain or hash trees or optimized logging technologies such as block-chain or hash trees or optimized logging
approaches. Doing so is out of the scope of this document but is an approaches. Doing so is out of the scope of this document but is an
anticipated improvement for future work. As such, the Registrar anticipated improvement for future work. As such, the registrar
client SHOULD anticipate new kinds of responses, and SHOULD provide client SHOULD anticipate new kinds of responses, and SHOULD provide
operator controls to indicate how to process unknown responses. operator controls to indicate how to process unknown responses.
5.7.2. Registrar audit log verification
Each time the Manufacturer Authorized Signing Authority (MASA) issues
a voucher, it places it into the audit log for that device. The
details are described in Section 5.7. The contents of the audit log
can express a variety of trust levels, and this section explains what
kind of trust a registrar can derive from the entries.
While the audit log provides a list of vouchers that were issued by
the MASA, the vouchers are issued in response to voucher-requests,
and it is the contents of the voucher-requests which determines how
meaningful the audit log entries are.
A registrar SHOULD use the log information to make an informed
decision regarding the continued bootstrapping of the pledge. The
exact policy is out of scope of this document as it depends on the
security requirements within the registrar domain. Equipment that is
purchased pre-owned can be expected to have an extensive history.
The following dicussion is provided to help explain the value of each
log element:
date: The date field provides the registrar an opportunity to divide
the log around known events such as the purchase date. Depending
on context known to the registrar or administrator evens before/
after certain dates can have different levels of importance. For
example for equipment that is expected to be new, and thus have no
history, it would be a surprise to find prior entries.
domainID: If the log includes an unexpected domainID then the pledge
could have imprinted on an unexpected domain. The registrar can
be expected to use a variety of techniques to define "unexpected"
ranging from white lists of prior domains to anomoly detection
(e.g. "this device was previously bound to a different domain than
any other device deployed"). Log entries can also be compared
against local history logs in search of discrepancies (e.g. "this
device was re-deployed some number of times internally but the
external audit log shows additional re-deployments our internal
logs are unaware of").
nonce: Nonceless entries mean the logged domainID could
theoretically trigger a reset of the pledge and then take over
management by using the existing nonceless voucher.
assertion: The assetion leaf in the voucher and audit log indicates
why the MASA issued the voucher. A "verified" entry means that
the MASA issued the associated voucher as a result of positive
verification of ownership but this can still be problematic for
registrar's that expected only new (not pre-owned) pledges. A
"logged" assertion informs the registrar that the prior vouchers
were issued with minimal verification. A "proximity" assertion
assures the registrar that the pledge was truly communicating with
the prior domain and thus provides assurance that the prior domain
really has deployed the pledge.
A relatively simple policy is to white list known (internal or
external) domainIDs and to require all vouchers to have a nonce and/
or require that all nonceless vouchers be from a subset (e.g. only
internal) domainIDs. A registrar MAY be configured to ignore the
history of the device but it is RECOMMENDED that this only be
configured if hardware assisted NEA [RFC5209] is supported.
5.8. EST Integration for PKI bootstrapping 5.8. EST Integration for PKI bootstrapping
The Pledge SHOULD follow the BRSKI operations with EST enrollment The pledge SHOULD follow the BRSKI operations with EST enrollment
operations including "CA Certificates Request", "CSR Attributes" and operations including "CA Certificates Request", "CSR Attributes" and
"Client Certificate Request" or "Server-Side Key Generation", etc. "Client Certificate Request" or "Server-Side Key Generation", etc.
This is a relatively seamless integration since BRSKI REST calls This is a relatively seamless integration since BRSKI REST calls
provide an automated alternative to the manual bootstrapping method provide an automated alternative to the manual bootstrapping method
described in [RFC7030]. As noted above, use of HTTP 1.1 persistent described in [RFC7030]. As noted above, use of HTTP 1.1 persistent
connections simplifies the Pledge state machine. connections simplifies the pledge state machine.
An ANIMA ANI Pledge MUST implement the EST automation extensions An ANIMA ANI pledge MUST implement the EST automation extensions
described below. They supplement the [RFC7030] EST to better support described below. They supplement the [RFC7030] EST to better support
automated devices that do not have an end user. automated devices that do not have an end user.
Although EST allows clients to obtain multiple certificates by Although EST allows clients to obtain multiple certificates by
sending multiple CSR requests BRSKI mandates use of the CSR sending multiple CSR requests BRSKI mandates use of the CSR
Attributes request and mandates that the Registrar validate the CSR Attributes request and mandates that the registrar validate the CSR
against the expected attributes. This implies that client requests against the expected attributes. This implies that client requests
will "look the same" and therefore result in a single logical will "look the same" and therefore result in a single logical
certificate being issued even if the client were to make multiple certificate being issued even if the client were to make multiple
requests. Registrars MAY contain more complex logic but doing so is requests. Registrars MAY contain more complex logic but doing so is
out-of-scope of this specification. BRSKI does not signal any out-of-scope of this specification. BRSKI does not signal any
enhancement or restriction to this capability. enhancement or restriction to this capability.
5.8.1. EST Distribution of CA Certificates 5.8.1. EST Distribution of CA Certificates
The Pledge MUST request the full EST Distribution of CA Certificates The pledge SHOULD request the full EST Distribution of CA
message. See RFC7030, section 4.1. Certificates message. See RFC7030, section 4.1.
This ensures that the Pledge has the complete set of current CA This ensures that the pledge has the complete set of current CA
certificates beyond the pinned-domain-cert (see Section 5.5.1 for a certificates beyond the pinned-domain-cert (see Section 5.5.1 for a
discussion of the limitations inherent in having a single certificate discussion of the limitations inherent in having a single certificate
instead of a full CA Certificates response.) Although these instead of a full CA Certificates response.) Although these
limitations are acceptable during initial bootstrapping, they are not limitations are acceptable during initial bootstrapping, they are not
appropriate for ongoing PKIX end entity certificate validation. appropriate for ongoing PKIX end entity certificate validation.
5.8.2. EST CSR Attributes 5.8.2. EST CSR Attributes
Automated bootstrapping occurs without local administrative Automated bootstrapping occurs without local administrative
configuration of the Pledge. In some deployments it is plausible configuration of the pledge. In some deployments it is plausible
that the Pledge generates a certificate request containing only that the pledge generates a certificate request containing only
identity information known to the Pledge (essentially the X.509 identity information known to the pledge (essentially the X.509
IDevID information) and ultimately receives a certificate containing IDevID information) and ultimately receives a certificate containing
domain specific identity information. Conceptually the CA has domain specific identity information. Conceptually the CA has
complete control over all fields issued in the end entity complete control over all fields issued in the end entity
certificate. Realistically this is operationally difficult with the certificate. Realistically this is operationally difficult with the
current status of PKI certificate authority deployments, where the current status of PKI certificate authority deployments, where the
CSR is submitted to the CA via a number of non-standard protocols. CSR is submitted to the CA via a number of non-standard protocols.
Even with all standardized protocols used, it could operationally be Even with all standardized protocols used, it could operationally be
problematic to expect that service specific certificate fields can be problematic to expect that service specific certificate fields can be
created by a CA that is likely operated by a group that has no created by a CA that is likely operated by a group that has no
insight into different network services/protocols used. For example, insight into different network services/protocols used. For example,
the CA could even be outsourced. the CA could even be outsourced.
To alleviate these operational difficulties, the Pledge MUST request To alleviate these operational difficulties, the pledge MUST request
the EST "CSR Attributes" from the EST server and the EST server needs the EST "CSR Attributes" from the EST server and the EST server needs
to be able to reply with the attributes necessary for use of the to be able to reply with the attributes necessary for use of the
certificate in its intended protocols/services. This approach allows certificate in its intended protocols/services. This approach allows
for minimal CA integrations and instead the local infrastructure (EST for minimal CA integrations and instead the local infrastructure (EST
server) informs the Pledge of the proper fields to include in the server) informs the pledge of the proper fields to include in the
generated CSR. This approach is beneficial to automated boostrapping generated CSR. This approach is beneficial to automated boostrapping
in the widest number of environments. in the widest number of environments.
If the hardwareModuleName in the X.509 IDevID is populated then it If the hardwareModuleName in the X.509 IDevID is populated then it
SHOULD by default be propagated to the LDevID along with the SHOULD by default be propagated to the LDevID along with the
hwSerialNum. The EST server SHOULD support local policy concerning hwSerialNum. The EST server SHOULD support local policy concerning
this functionality. this functionality.
In networks using the BRSKI enrolled certificate to authenticate the In networks using the BRSKI enrolled certificate to authenticate the
ACP (Autonomic Control Plane), the EST attributes MUST include the ACP (Autonomic Control Plane), the EST attributes MUST include the
"ACP information" field. See "ACP information" field. See
[I-D.ietf-anima-autonomic-control-plane] for more details. [I-D.ietf-anima-autonomic-control-plane] for more details.
The Registar MUST also confirm that the resulting CSR is formatted as The registrar MUST also confirm that the resulting CSR is formatted
indicated before forwarding the request to a CA. If the Registar is as indicated before forwarding the request to a CA. If the registrar
communicating with the CA using a protocol such as full CMC, which is communicating with the CA using a protocol such as full CMC, which
provides mechanisms to override the CSR attributes, then these provides mechanisms to override the CSR attributes, then these
mechanisms MAY be used even if the client ignores CSR Attribute mechanisms MAY be used even if the client ignores CSR Attribute
guidance. guidance.
5.8.3. EST Client Certificate Request 5.8.3. EST Client Certificate Request
The Pledge MUST request a new client certificate. See RFC7030, The pledge MUST request a new client certificate. See RFC7030,
section 4.2. section 4.2.
5.8.4. Enrollment Status Telemetry 5.8.4. Enrollment Status Telemetry
For automated bootstrapping of devices, the adminstrative elements For automated bootstrapping of devices, the adminstrative elements
providing bootstrapping also provide indications to the system providing bootstrapping also provide indications to the system
administrators concerning device lifecycle status. This might administrators concerning device lifecycle status. This might
include information concerning attempted bootstrapping messages seen include information concerning attempted bootstrapping messages seen
by the client, MASA provides logs and status of credential by the client, MASA provides logs and status of credential
enrollment. [RFC7030] assumes an end user and therefore does not enrollment. [RFC7030] assumes an end user and therefore does not
skipping to change at page 51, line 15 skipping to change at page 53, line 15
Within the server logs the server MUST capture if this message was Within the server logs the server MUST capture if this message was
received over an TLS session with a matching client certificate. received over an TLS session with a matching client certificate.
This allows for clients that wish to minimize their crypto operations This allows for clients that wish to minimize their crypto operations
to simply POST this response without renegotiating the TLS session - to simply POST this response without renegotiating the TLS session -
at the cost of the server not being able to accurately verify that at the cost of the server not being able to accurately verify that
enrollment was truly successful. enrollment was truly successful.
5.8.5. Multiple certificates 5.8.5. Multiple certificates
Pledges that require multiple certificates could establish direct EST Pledges that require multiple certificates could establish direct EST
connections to the Registrar. connections to the registrar.
5.8.6. EST over CoAP 5.8.6. EST over CoAP
This document describes extensions to EST for the purposes of This document describes extensions to EST for the purposes of
bootstrapping of remote key infrastructures. Bootstrapping is bootstrapping of remote key infrastructures. Bootstrapping is
relevant for CoAP enrollment discussions as well. The defintion of relevant for CoAP enrollment discussions as well. The defintion of
EST and BRSKI over CoAP is not discussed within this document beyond EST and BRSKI over CoAP is not discussed within this document beyond
ensuring proxy support for CoAP operations. Instead it is ensuring proxy support for CoAP operations. Instead it is
anticipated that a definition of CoAP mappings will occur in anticipated that a definition of CoAP mappings will occur in
subsequent documents such as [I-D.vanderstok-ace-coap-est] and that subsequent documents such as [I-D.vanderstok-ace-coap-est] and that
CoAP mappings for BRSKI will be discussed either there or in future CoAP mappings for BRSKI will be discussed either there or in future
work. work.
6. Reduced security operational modes 6. Reduced security operational modes
A common requirement of bootstrapping is to support less secure A common requirement of bootstrapping is to support less secure
operational modes for support specific use cases. The following operational modes for support specific use cases. The following
sections detail specific ways that the Pledge, Registrar and MASA can sections detail specific ways that the pledge, registrar and MASA can
be configured to run in a less secure mode for the indicated reasons. be configured to run in a less secure mode for the indicated reasons.
This section is considered non-normative: use suggested methods MUST This section is considered non-normative: use suggested methods MUST
be detailed in specific profiles of BRSKI. This is the subject for be detailed in specific profiles of BRSKI. This is the subject for
future work. future work.
6.1. Trust Model 6.1. Trust Model
+--------+ +---------+ +------------+ +------------+ +--------+ +---------+ +------------+ +------------+
| Pledge | | Circuit | | Domain | |Manufacturer| | Pledge | | Join | | Domain | |Manufacturer|
| | | Proxy | | Registrar | | Service | | | | Proxy | | Registrar | | Service |
| | | | | | | (Internet) | | | | | | | | (Internet) |
+--------+ +---------+ +------------+ +------------+ +--------+ +---------+ +------------+ +------------+
Figure 10 Figure 10
Pledge: The Pledge could be compromised and providing an attack Pledge: The pledge could be compromised and providing an attack
vector for malware. The entity is trusted to only imprint using vector for malware. The entity is trusted to only imprint using
secure methods described in this document. Additional endpoint secure methods described in this document. Additional endpoint
assessment techniques are RECOMMENDED but are out-of-scope of this assessment techniques are RECOMMENDED but are out-of-scope of this
document. document.
Proxy: Provides proxy functionalities but is not involved in Join Proxy: Provides proxy functionalities but is not involved in
security considerations. security considerations.
Registrar: When interacting with a MASA server a Registrar makes all Registrar: When interacting with a MASA server a registrar makes all
decisions. When Ownership Vouchers are involved a Registrar is decisions. For Ownership Audit Vouchers (see
only a conduit and all security decisions are made on the [I-D.ietf-anima-voucher]) the registrar is provided an opportunity
manufacturer service. to accept MASA server decisions.
Vendor Service, MASA: This form of manufacturer service is trusted Vendor Service, MASA: This form of manufacturer service is trusted
to accurately log all claim attempts and to provide authoritative to accurately log all claim attempts and to provide authoritative
log information to Registrars. The MASA does not know which log information to registrars. The MASA does not know which
devices are associated with which domains. These claims could be devices are associated with which domains. These claims could be
strengthened by using cryptographic log techniques to provide strengthened by using cryptographic log techniques to provide
append only, cryptographic assured, publicly auditable logs. append only, cryptographic assured, publicly auditable logs.
Current text provides only for a trusted manufacturer. Current text provides only for a trusted manufacturer.
Vendor Service, Ownership Validation: This form of manufacturer Vendor Service, Ownership Validation: This form of manufacturer
service is trusted to accurately know which device is owned by service is trusted to accurately know which device is owned by
which domain. which domain.
6.2. Pledge security reductions 6.2. Pledge security reductions
The Pledge can choose to accept vouchers using less secure methods. The pledge can choose to accept vouchers using less secure methods.
These methods enable offline and emergency (touch based) deployment These methods enable offline and emergency (touch based) deployment
use cases: use cases:
1. The Pledge MUST accept nonceless vouchers. This allows for 1. The pledge MUST accept nonceless vouchers. This allows for a use
offline use cases. Logging and validity periods address the case where the registrar can not connect to the MASA at the
inherent security considerations of supporting these use cases. deployment time. Logging and validity periods address the
security considerations of supporting these use cases.
2. The Pledge MAY support "trust on first use" for physical 2. The pledge MAY support "trust on first use" for physical
interfaces such as a local console port or physical user interfaces such as a local console port or physical user
interface but MUST NOT support "trust on first use" on network interface but MUST NOT support "trust on first use" on network
interfaces. This is because "trust on first use" permanently interfaces. This is because "trust on first use" permanently
degrades the security for all use cases. degrades the security for all use cases.
3. The Pledge MAY have an operational mode where it skips Voucher 3. The pledge MAY have an operational mode where it skips voucher
validation one time. For example if a physical button is validation one time. For example if a physical button is
depressed during the bootstrapping operation. This can be useful depressed during the bootstrapping operation. This can be useful
if the manufacturer service is unavailable. This behavior SHOULD if the manufacturer service is unavailable. This behavior SHOULD
be available via local configuration or physical presence methods be available via local configuration or physical presence methods
(such as use of a serial/craft console) to ensure new entities (such as use of a serial/craft console) to ensure new entities
can always be deployed even when autonomic methods fail. This can always be deployed even when autonomic methods fail. This
allows for unsecured imprint. allows for unsecured imprint.
It is RECOMMENDED that "trust on first use" or skipping voucher It is RECOMMENDED that "trust on first use" or skipping voucher
validation only be available if hardware assisted Network Endpoint validation only be available if hardware assisted Network Endpoint
Assessment [RFC5209] is supported. This recommendation ensures that Assessment [RFC5209] is supported. This recommendation ensures that
domain network monitoring can detect innappropriate use of offline or domain network monitoring can detect innappropriate use of offline or
emergency deployment procedures. emergency deployment procedures.
6.3. Registrar security reductions 6.3. Registrar security reductions
A Registrar can choose to accept devices using less secure methods. A registrar can choose to accept devices using less secure methods.
These methods are acceptable when low security models are needed, as These methods are acceptable when low security models are needed, as
the security decisions are being made by the local administrator, but the security decisions are being made by the local administrator, but
they MUST NOT be the default behavior: they MUST NOT be the default behavior:
1. A Registrar MAY choose to accept all devices, or all devices of a 1. A registrar MAY choose to accept all devices, or all devices of a
particular type, at the administrator's discretion. This could particular type, at the administrator's discretion. This could
occur when informing all Registrars of unique identifiers of new occur when informing all registrars of unique identifiers of new
entities might be operationally difficult. entities might be operationally difficult.
2. A Registrar MAY choose to accept devices that claim a unique 2. A registrar MAY choose to accept devices that claim a unique
identity without the benefit of authenticating that claimed identity without the benefit of authenticating that claimed
identity. This could occur when the Pledge does not include an identity. This could occur when the pledge does not include an
X.509 IDevID factory installed credential. New Entities without X.509 IDevID factory installed credential. New Entities without
an X.509 IDevID credential MAY form the Section 5.2 request using an X.509 IDevID credential MAY form the Section 5.2 request using
the Section 5.4 format to ensure the Pledge's serial number the Section 5.4 format to ensure the pledge's serial number
information is provided to the Registar (this includes the IDevID information is provided to the registrar (this includes the
AuthorityKeyIdentifier value, which would be statically IDevID AuthorityKeyIdentifier value, which would be statically
configured on the Pledge.) The Pledge MAY refuse to provide a configured on the pledge.) The pledge MAY refuse to provide a
TLS client certificate (as one is not available.) The Pledge TLS client certificate (as one is not available.) The pledge
SHOULD support HTTP-based or certificate-less TLS authentication SHOULD support HTTP-based or certificate-less TLS authentication
as described in EST RFC7030 section 3.3.2. A Registrar MUST NOT as described in EST RFC7030 section 3.3.2. A registrar MUST NOT
accept unauthenticated New Entities unless it has been configured accept unauthenticated New Entities unless it has been configured
to do so by an administrator that has verified that only expected to do so by an administrator that has verified that only expected
new entities can communicate with a Registrar (presumably via a new entities can communicate with a registrar (presumably via a
physically secured perimeter.) physically secured perimeter.)
3. A Registrar MAY submit a nonceless voucher-requests to the MASA 3. A registrar MAY submit a nonceless voucher-requests to the MASA
service (by not including a nonce in the voucher-request.) The service (by not including a nonce in the voucher-request.) The
resulting Vouchers can then be stored by the Registrar until they resulting vouchers can then be stored by the registrar until they
are needed during bootstrapping operations. This is for use are needed during bootstrapping operations. This is for use
cases where the target network is protected by an air gap and cases where the target network is protected by an air gap and
therefore cannot contact the MASA service during Pledge therefore cannot contact the MASA service during pledge
deployment. deployment.
4. A Registrar MAY ignore unrecognized nonceless log entries. This 4. A registrar MAY ignore unrecognized nonceless log entries. This
could occur when used equipment is purchased with a valid history could occur when used equipment is purchased with a valid history
being deployed in air gap networks that required permanent being deployed in air gap networks that required permanent
Vouchers. vouchers.
6.4. MASA security reductions 6.4. MASA security reductions
Lower security modes chosen by the MASA service affect all device Lower security modes chosen by the MASA service affect all device
deployments unless bound to the specific device identities. In which deployments unless bound to the specific device identities. In which
case these modes can be provided as additional features for specific case these modes can be provided as additional features for specific
customers. The MASA service can choose to run in less secure modes customers. The MASA service can choose to run in less secure modes
by: by:
1. Not enforcing that a nonce is in the Voucher. This results in 1. Not enforcing that a nonce is in the voucher. This results in
distribution of a Voucher that never expires and in effect makes distribution of a voucher that never expires and in effect makes
the Domain an always trusted entity to the Pledge during any the Domain an always trusted entity to the pledge during any
subsequent bootstrapping attempts. That this occurred is subsequent bootstrapping attempts. That this occurred is
captured in the log information so that the Registrar can make captured in the log information so that the registrar can make
appropriate security decisions when a Pledge joins the Domain. appropriate security decisions when a pledge joins the Domain.
This is useful to support use cases where Registrars might not be This is useful to support use cases where registrars might not be
online during actual device deployment. Because this results in online during actual device deployment. Because this results in
a long lived Voucher and does not require the proof that the a long lived voucher and does not require the proof that the
device is online, this is only accepted when the Registrar is device is online, this is only accepted when the registrar is
authenticated by the MASA server and authorized to provide this authenticated by the MASA server and authorized to provide this
functionality. The MASA server is RECOMMENDED to use this functionality. The MASA server is RECOMMENDED to use this
functionality only in concert with an enhanced level of ownership functionality only in concert with an enhanced level of ownership
tracking (out-of-scope.) If the Pledge device is known to have a tracking (out-of-scope.) If the pledge device is known to have a
real-time-clock that is set from the factory, use of a voucher real-time-clock that is set from the factory, use of a voucher
validity period is RECOMMENDED. validity period is RECOMMENDED.
2. Not verifying ownership before responding with a Voucher. This 2. Not verifying ownership before responding with a voucher. This
is expected to be a common operational model because doing so is expected to be a common operational model because doing so
relieves the manufacturer providing MASA services from having to relieves the manufacturer providing MASA services from having to
track ownership during shipping and supply chain and allows for a track ownership during shipping and supply chain and allows for a
very low overhead MASA service. A Registrar uses the audit log very low overhead MASA service. A registrar uses the audit log
information as a defense in depth strategy to ensure that this information as a defense in depth strategy to ensure that this
does not occur unexpectedly (for example when purchasing new does not occur unexpectedly (for example when purchasing new
equipment the Registrar would throw an error if any audit log equipment the registrar would throw an error if any audit log
information is reported.) The MASA should verify the 'prior- information is reported.) The MASA SHOULD verify the 'prior-
signed-voucher' information for Pledges that support that signed-voucher-request' information for pledges that support that
functionality. This provides a proof-of-proximity check that functionality. This provides a proof-of-proximity check that
reduces the need for ownership verification. reduces the need for ownership verification.
7. IANA Considerations 7. IANA Considerations
This document requires the following IANA actions: This document requires the following IANA actions:
7.1. Well-known EST registration 7.1. Well-known EST registration
This document extends the definitions of "est" (so far defined via This document extends the definitions of "est" (so far defined via
skipping to change at page 55, line 34 skipping to change at page 57, line 34
registration, with this document as the reference: registration, with this document as the reference:
o version o version
o Status o Status
o Reason o Reason
o reason-context o reason-context
7.4. DNS Service Names
IANA is requested to register the following Service Names:
Service Name: _brski-proxy
Transport Protocol(s): tcp
Assignee: IESG <iesg@ietf.org>.
Contact: IETF Chair <chair@ietf.org>
Description: The Bootstrapping Remote Secure Key Infrastructures Proxy
Reference: [This document]
Service Name: _brski-registrar
Transport Protocol(s): tcp
Assignee: IESG <iesg@ietf.org>.
Contact: IETF Chair <chair@ietf.org>
Description: The Bootstrapping Remote Secure Key Infrastructures Registrar
Reference: [This document]
7.5. MUD File Extension for the MASA server
The IANA is requested to list the name "masa" in the MUD extensions
registry defined in [I-D.ietf-opsawg-mud]. Its use is documented in
Appendix D.
8. Privacy Considerations 8. Privacy Considerations
8.1. MASA authorization log 8.1. MASA audit log
The MASA authorization log includes a hash of the domainID for each The MASA audit log includes a hash of the domainID for each Registrar
Registrar a voucher has been issued to. This information is closely a voucher has been issued to. This information is closely related to
related to the actual domain identity, especially when paired with the actual domain identity, especially when paired with the anti-DDoS
the anti-DDoS authentication information the MASA might collect. authentication information the MASA might collect. This could
This could provide sufficient information for the MASA service to provide sufficient information for the MASA service to build a
build a detailed understanding the devices that have been provisioned detailed understanding the devices that have been provisioned within
within a domain. a domain.
There are a number of design choices that mitigate this risk. The There are a number of design choices that mitigate this risk. The
domain can maintain some privacy since it has not necessarily been domain can maintain some privacy since it has not necessarily been
authenticated and is not authoritatively bound to the supply chain. authenticated and is not authoritatively bound to the supply chain.
Additionally the domainID captures only the unauthenticated subject Additionally the domainID captures only the unauthenticated subject
key identifier of the domain. A privacy sensitive domain could key identifier of the domain. A privacy sensitive domain could
theoretically generate a new domainID for each device being deployed. theoretically generate a new domainID for each device being deployed.
Similarly a privacy sensitive domain would likely purchase devices Similarly a privacy sensitive domain would likely purchase devices
that support proximity assertions from a manufacturer that does not that support proximity assertions from a manufacturer that does not
require sales channel integrations. This would result in a require sales channel integrations. This would result in a
significant level of privacy while maintaining the security significant level of privacy while maintaining the security
characteristics provided by Registrar based audit log inspection. characteristics provided by Registrar based audit log inspection.
9. Security Considerations 9. Security Considerations
There are uses cases where the MASA could be unavailable or There are uses cases where the MASA could be unavailable or
uncooperative to the Registrar. They include planned and unplanned uncooperative to the Registrar. They include planned and unplanned
skipping to change at page 56, line 18 skipping to change at page 58, line 42
significant level of privacy while maintaining the security significant level of privacy while maintaining the security
characteristics provided by Registrar based audit log inspection. characteristics provided by Registrar based audit log inspection.
9. Security Considerations 9. Security Considerations
There are uses cases where the MASA could be unavailable or There are uses cases where the MASA could be unavailable or
uncooperative to the Registrar. They include planned and unplanned uncooperative to the Registrar. They include planned and unplanned
network partitions, changes to MASA policy, or other instances where network partitions, changes to MASA policy, or other instances where
MASA policy rejects a claim. These introduce an operational risk to MASA policy rejects a claim. These introduce an operational risk to
the Registrar owner that MASA behavior might limit the ability to re- the Registrar owner that MASA behavior might limit the ability to re-
boostrap a Pledge device. For example this might be an issue during boostrap a pledge device. For example this might be an issue during
disaster recovery. This risk can be mitigated by Registrars that disaster recovery. This risk can be mitigated by Registrars that
request and maintain long term copies of "nonceless" Vouchers. In request and maintain long term copies of "nonceless" vouchers. In
that way they are guaranteed to be able to repeat bootstrapping for that way they are guaranteed to be able to repeat bootstrapping for
their devices. their devices.
The issuance of nonceless vouchers themselves creates a security The issuance of nonceless vouchers themselves creates a security
concern. If the Registrar of a previous domain can intercept concern. If the Registrar of a previous domain can intercept
protocol communications then it can use a previously issued nonceless protocol communications then it can use a previously issued nonceless
voucher to establish management control of a Pledge device even after voucher to establish management control of a pledge device even after
having sold it. This risk is mitigated by recording the issuance of having sold it. This risk is mitigated by recording the issuance of
such vouchers in the MASA audit log that is verified by the such vouchers in the MASA audit log that is verified by the
subsequent Registrar. This reduces the resale value of the equipment subsequent Registrar. This reduces the resale value of the equipment
because future owners will detect the lowered security inherent in because future owners will detect the lowered security inherent in
the existence of a nonceless voucher that would be trusted by their the existence of a nonceless voucher that would be trusted by their
Pledge. This reflects a balance between partition resistant recovery pledge. This reflects a balance between partition resistant recovery
and security of future bootstrapping. Registrars take the Pledge's and security of future bootstrapping. Registrars take the pledge's
audit history into account when applying policy to new devices. audit history into account when applying policy to new devices.
The MASA server is exposed to DoS attacks wherein attackers claim an The MASA server is exposed to DoS attacks wherein attackers claim an
unbounded number of devices. Ensuring a Registrar is representative unbounded number of devices. Ensuring a registrar is representative
of a valid manufacturer customer, even without validating ownership of a valid manufacturer customer, even without validating ownership
of specific Pledge devices, helps to mitigate this. Pledge of specific pledge devices, helps to mitigate this. Pledge
signatures on the Pledge voucher-request, as forwarded by the signatures on the pledge voucher-request, as forwarded by the
Registrar in the prior-signed-voucher field of the Registrar voucher- registrar in the prior-signed-voucher-request field of the registrar
request, significantly reduce this risk by ensuring the MASA can voucher-request, significantly reduce this risk by ensuring the MASA
confirm proximity between the Pledge and the Registrar making the can confirm proximity between the pledge and the registrar making the
request. This mechanism is optional to allow for constrained request. This mechanism is optional to allow for constrained
devices. devices.
To facilitate logging and administrative oversight in addition to To facilitate logging and administrative oversight in addition to
triggering Registration verification of MASA logs the Pledge reports triggering Registration verification of MASA logs the pledge reports
on Voucher parsing status to the Registrar. In the case of a on voucher parsing status to the registrar. In the case of a
failure, this information is informative to a potentially malicious failure, this information is informative to a potentially malicious
Registar but this is mandated anyway because of the operational registrar but this is mandated anyway because of the operational
benefits of an informed administrator in cases where the failure is benefits of an informed administrator in cases where the failure is
indicative of a problem. The Registrar is RECOMMENDED to verify MASA indicative of a problem. The registrar is RECOMMENDED to verify MASA
logs if voucher status telemetry is not received. logs if voucher status telemetry is not received.
To facilitate truely limited clients EST RFC7030 section 3.3.2 To facilitate truely limited clients EST RFC7030 section 3.3.2
requirements that the client MUST support a client authentication requirements that the client MUST support a client authentication
model have been reduced in Section 6 to a statement that the model have been reduced in Section 6 to a statement that the
Registrar "MAY" choose to accept devices that fail cryptographic registrar "MAY" choose to accept devices that fail cryptographic
authentication. This reflects current (poor) practices in shipping authentication. This reflects current (poor) practices in shipping
devices without a cryptographic identity that are NOT RECOMMENDED. devices without a cryptographic identity that are NOT RECOMMENDED.
During the provisional period of the connection the Pledge MUST treat During the provisional period of the connection the pledge MUST treat
all HTTP header and content data as untrusted data. HTTP libraries all HTTP header and content data as untrusted data. HTTP libraries
are regularly exposed to non-secured HTTP traffic: mature libraries are regularly exposed to non-secured HTTP traffic: mature libraries
should not have any problems. should not have any problems.
Pledges might chose to engage in protocol operations with multiple Pledges might chose to engage in protocol operations with multiple
discovered Registrars in parallel. As noted above they will only do discovered registrars in parallel. As noted above they will only do
so with distinct nonce values, but the end result could be multiple so with distinct nonce values, but the end result could be multiple
vouchers issued from the MASA if all Registrars attempt to claim the vouchers issued from the MASA if all registrars attempt to claim the
device. This is not a failure and the Pledge choses whichever device. This is not a failure and the pledge choses whichever
voucher to accept based on internal logic. The Registrar's verifying voucher to accept based on internal logic. The registrar's verifying
log information will see multiple entries and take this into account log information will see multiple entries and take this into account
for their analytics purposes. for their analytics purposes.
9.1. Freshness in Voucher-Requests 9.1. Freshness in Voucher-Requests
A concern has been raised that the Pledge voucher-request should A concern has been raised that the pledge voucher-request should
contain some content (a nonce) provided by the Registrar and/or MASA contain some content (a nonce) provided by the registrar and/or MASA
in order for those actors to verify that the Pledge voucher-request in order for those actors to verify that the pledge voucher-request
is fresh. is fresh.
There are a number of operational problems with getting a nonce from There are a number of operational problems with getting a nonce from
the MASA to the Pledge. It is somewhat easier to collect a random the MASA to the pledge. It is somewhat easier to collect a random
value from the Registrar, but as the Registrar is not yet vouched value from the registrar, but as the registrar is not yet vouched
for, such a Registrar nonce has little value. There are privacy and for, such a registrar nonce has little value. There are privacy and
logistical challenges to addressing these operational issues, so if logistical challenges to addressing these operational issues, so if
such a thing were to be considered, it would have to provide some such a thing were to be considered, it would have to provide some
clear value. This section examines the impacts of not having a fresh clear value. This section examines the impacts of not having a fresh
Pledge voucher-request. pledge voucher-request.
Because the Registrar authenticates the Pledge, a full Man-in-the- Because the registrar authenticates the pledge, a full Man-in-the-
Middle attack is not possible, despite the provisional TLS Middle attack is not possible, despite the provisional TLS
authentication by the Pledge (see Section 5.) Instead we examine the authentication by the pledge (see Section 5.) Instead we examine the
case of a fake Registrar (Rm) that communicates with the Pledge in case of a fake registrar (Rm) that communicates with the pledge in
parallel or in close time proximity with the intended Registrar. parallel or in close time proximity with the intended registrar.
(This scenario is intentionally supported as described in (This scenario is intentionally supported as described in
Section 4.1.) Section 4.1.)
The fake Registrar (Rm) can obtain a voucher signed by the MASA
The fake registrar (Rm) can obtain a voucher signed by the MASA
either directly or through arbitrary intermediaries. Assuming that either directly or through arbitrary intermediaries. Assuming that
the MASA accepts the Registar voucher-request (either because Rm is the MASA accepts the registrar voucher-request (either because Rm is
collaborating with a legitimate Registrar according to supply chain collaborating with a legitimate registrar according to supply chain
information, or because the MASA is in audit-log only mode), then a information, or because the MASA is in audit-log only mode), then a
voucher linking the Pledge to the Registrar Rm is issued. voucher linking the pledge to the registrar Rm is issued.
Such a voucher, when passed back to the Pledge, would link the Pledge Such a voucher, when passed back to the pledge, would link the pledge
to Registrar Rm, and would permit the Pledge to end the provisional to registrar Rm, and would permit the pledge to end the provisional
state. It now trusts Rm and, if it has any security vulnerabilities state. It now trusts Rm and, if it has any security vulnerabilities
leveragable by an Rm with full administrative control, can be assumed leveragable by an Rm with full administrative control, can be assumed
to be a threat against the intended Registrar. to be a threat against the intended registrar.
This flow is mitigated by the intended Registar verifying the audit This flow is mitigated by the intended registrar verifying the audit
logs available from the MASA as described in Section 5.7. Rm might logs available from the MASA as described in Section 5.7. Rm might
chose to wait until after the intended Registrar completes the chose to wait until after the intended registrar completes the
authorization process before submitting the now-stale Pledge voucher- authorization process before submitting the now-stale pledge voucher-
request. The Rm would need to remove the Pledge's nonce. request. The Rm would need to remove the pledge's nonce.
In order to successfully use the resulting "stale voucher" Rm would In order to successfully use the resulting "stale voucher" Rm would
have to attack the Pledge and return it to a bootstrapping enabled have to attack the pledge and return it to a bootstrapping enabled
state. This would require wiping the Pledge of current configuration state. This would require wiping the pledge of current configuration
and triggering a re-bootstrapping of the Pledge. This is no more and triggering a re-bootstrapping of the pledge. This is no more
likely than simply taking control of the Pledge directly but if this likely than simply taking control of the pledge directly but if this
is a consideration the target network is RECOMMENDED to take the is a consideration the target network is RECOMMENDED to take the
following steps: following steps:
o Ongoing network monitoring for unexpected bootstrapping attempts o Ongoing network monitoring for unexpected bootstrapping attempts
by Pledges. by pledges.
o Retreival and examination of MASA log information upon the o Retreival and examination of MASA log information upon the
occurance of any such unexpected events. Rm will be listed in the occurance of any such unexpected events. Rm will be listed in the
logs. logs.
9.2. Trusting manufacturers 9.2. Trusting manufacturers
The BRSKI extensions to EST permit a new pledge to be completely The BRSKI extensions to EST permit a new pledge to be completely
configured with domain specific trust anchors. The link from built- configured with domain specific trust anchors. The link from built-
in manufacturer-provided trust anchors to domain-specific trust in manufacturer-provided trust anchors to domain-specific trust
skipping to change at page 63, line 7 skipping to change at page 65, line 34
Networking", draft-ietf-anima-reference-model-06 (work in Networking", draft-ietf-anima-reference-model-06 (work in
progress), February 2018. progress), February 2018.
[I-D.ietf-netconf-zerotouch] [I-D.ietf-netconf-zerotouch]
Watsen, K., Abrahamsson, M., and I. Farrer, "Zero Touch Watsen, K., Abrahamsson, M., and I. Farrer, "Zero Touch
Provisioning for Networking Devices", draft-ietf-netconf- Provisioning for Networking Devices", draft-ietf-netconf-
zerotouch-21 (work in progress), March 2018. zerotouch-21 (work in progress), March 2018.
[I-D.ietf-opsawg-mud] [I-D.ietf-opsawg-mud]
Lear, E., Droms, R., and D. Romascanu, "Manufacturer Usage Lear, E., Droms, R., and D. Romascanu, "Manufacturer Usage
Description Specification", draft-ietf-opsawg-mud-18 (work Description Specification", draft-ietf-opsawg-mud-20 (work
in progress), March 2018. in progress), April 2018.
[I-D.richardson-anima-state-for-joinrouter] [I-D.richardson-anima-state-for-joinrouter]
Richardson, M., "Considerations for stateful vs stateless Richardson, M., "Considerations for stateful vs stateless
join router in ANIMA bootstrap", draft-richardson-anima- join router in ANIMA bootstrap", draft-richardson-anima-
state-for-joinrouter-02 (work in progress), January 2018. state-for-joinrouter-02 (work in progress), January 2018.
[I-D.vanderstok-ace-coap-est] [I-D.vanderstok-ace-coap-est]
Stok, P., Kampanakis, P., Kumar, S., Richardson, M., Stok, P., Kampanakis, P., Kumar, S., Richardson, M.,
Furuhed, M., and S. Raza, "EST over secure CoAP (EST- Furuhed, M., and S. Raza, "EST over secure CoAP (EST-
coaps)", draft-vanderstok-ace-coap-est-04 (work in coaps)", draft-vanderstok-ace-coap-est-04 (work in
skipping to change at page 64, line 34 skipping to change at page 67, line 13
papers/1999-StajanoAnd-duckling.pdf>. papers/1999-StajanoAnd-duckling.pdf>.
[TR069] Broadband Forum, "TR-69: CPE WAN Management Protocol", [TR069] Broadband Forum, "TR-69: CPE WAN Management Protocol",
February 2018, <https://www.broadband-forum.org/ February 2018, <https://www.broadband-forum.org/
standards-and-software/technical-specifications/ standards-and-software/technical-specifications/
tr-069-files-tools>. tr-069-files-tools>.
Appendix A. IPv4 and non-ANI operations Appendix A. IPv4 and non-ANI operations
The secification of BRSKI in Section 4 intentionally only covers the The secification of BRSKI in Section 4 intentionally only covers the
mechanisms for an IPv6 Pledge using Link-Local addresses. This mechanisms for an IPv6 pledge using Link-Local addresses. This
section describes non-normative extensions that can be used in other section describes non-normative extensions that can be used in other
environments. environments.
A.1. IPv4 Link Local addresses A.1. IPv4 Link Local addresses
Instead of an IPv6 link-local address, an IPv4 address may be Instead of an IPv6 link-local address, an IPv4 address may be
generated using [RFC3927] Dynamic Configuration of IPv4 Link-Local generated using [RFC3927] Dynamic Configuration of IPv4 Link-Local
Addresses. Addresses.
In the case that an IPv4 Link-Local address is formed, then the In the case that an IPv4 Link-Local address is formed, then the
skipping to change at page 65, line 7 skipping to change at page 67, line 35
(circuit) proxy. (circuit) proxy.
A.2. Use of DHCPv4 A.2. Use of DHCPv4
The Plege MAY obtain an IP address via DHCP [RFC2131]. The DHCP The Plege MAY obtain an IP address via DHCP [RFC2131]. The DHCP
provided parameters for the Domain Name System can be used to perform provided parameters for the Domain Name System can be used to perform
DNS operations if all local discovery attempts fail. DNS operations if all local discovery attempts fail.
Appendix B. mDNS / DNSSD proxy discovery options Appendix B. mDNS / DNSSD proxy discovery options
The Pledge MAY perform DNS-based Service Discovery [RFC6763] over Pledge discovery of the proxy (Section 4.1) MAY be performed with
Multicast DNS [RFC6762] searching for the service DNS-based Service Discovery [RFC6763] over Multicast DNS [RFC6762] to
"_bootstrapks._tcp.local.". discover the proxy at "_brski-proxy._tcp.local.".
A non-ANI Proxy MAY perform DNS-based Service Discovery using unicast Proxy discovery of the registrar (Section 4.3) MAY be performed with
DNS to discover Registrars searching for searching for the service DNS-based Service Discovery over Multicast DNS to discover registrars
"_brski-registrar._tcp.local.". by searching for the service "_brski-registrar._tcp.local.".
To prevent unaccceptable levels of network traffic, when using mDNS, To prevent unaccceptable levels of network traffic, when using mDNS,
the congestion avoidance mechanisms specified in [RFC6762] section 7 the congestion avoidance mechanisms specified in [RFC6762] section 7
MUST be followed. The Pledge SHOULD listen for an unsolicited MUST be followed. The pledge SHOULD listen for an unsolicited
broadcast response as described in [RFC6762]. This allows devices to broadcast response as described in [RFC6762]. This allows devices to
avoid announcing their presence via mDNS broadcasts and instead avoid announcing their presence via mDNS broadcasts and instead
silently join a network by watching for periodic unsolicited silently join a network by watching for periodic unsolicited
broadcast responses. broadcast responses.
The service searched for is "_bootstrapks._tcp.example.com". In this Discovery of registrar MAY also be performed with DNS-based service
case the domain "example.com" is discovered as described in [RFC6763] discovery by searching for the service "_brski-
section 11. This method is only available if the host has received a registrar._tcp.example.com". In this case the domain "example.com"
useable IPv4 address via DHCPv4 as suggested in Appendix A.2. is discovered as described in [RFC6763] section 11 (Appendix A.2
suggests the use of DHCP parameters).
If no local bootstrapks service is located using the GRASP If no local proxy or registrar service is located using the GRASP
mechanisms, or the above mentioned DNS-based Service Discovery mechanisms or the above mentioned DNS-based Service Discovery methods
methods, the Pledge MAY contact a well known manufacturer provided the pledge MAY contact a well known manufacturer provided
bootstrapping server by performing a DNS lookup using a well known bootstrapping server by performing a DNS lookup using a well known
URI such as "bootstrapks.manufacturer-example.com". The details of URI such as "brski-registrar.manufacturer.example.com". The details
the URI are manufacturer specific. Manufacturers that leverage this of the URI are manufacturer specific. Manufacturers that leverage
method on the Pledge are responsible for providing the bootstrapks this method on the pledge are responsible for providing the registrar
service. Also see Section 2.7. service. Also see Section 2.7.
The current DNS services returned during each query are maintained The current DNS services returned during each query are maintained
until bootstrapping is completed. If bootstrapping fails and the until bootstrapping is completed. If bootstrapping fails and the
Pledge returns to the Discovery state, it picks up where it left off pledge returns to the Discovery state, it picks up where it left off
and continues attempting bootstrapping. For example, if the first and continues attempting bootstrapping. For example, if the first
Multicast DNS _bootstrapks._tcp.local response doesn't work then the Multicast DNS _bootstrapks._tcp.local response doesn't work then the
second and third responses are tried. If these fail the Pledge moves second and third responses are tried. If these fail the pledge moves
on to normal DNS-based Service Discovery. on to normal DNS-based Service Discovery.
Appendix C. IPIP Join Proxy mechanism Appendix C. IPIP Join Proxy mechanism
The Circuit Proxy mechanism suffers from requiring a state on the The circuit proxy mechanism suffers from requiring a state on the
Join Proxy for each connection that is relayed. The Circuit Proxy proxy for each connection that is relayed. The proxy can be
can be considered a kind of Algorithm Gateway (see [RFC2663], section considered a kind of Algorithm Gateway (see [RFC2663], section 2.9).
2.9).
An alternative to proxying at the TCP layer is to selectively forward An alternative to proxying at the TCP layer is to selectively forward
at the IP layer. This moves all per-connection to the Join at the IP layer. This moves all per-connection state to the
Registrar. The IPIP tunnel statelessly forwards packets. This registrar. The IPIP tunnel statelessly forwards packets. This
section provides some explanation of some of the details of the section provides explanation of some of the details of the registrar
Registrar discovery procotol, which are not important to Circuit discovery procotol, which are not important to proxy, and some
Proxy, and some implementation advice. implementation advice.
The IPIP tunnel is described in [RFC2473]. Each such tunnel is The IPIP tunnel is described in [RFC2473]. Each such tunnel is
considered a unidirectional construct, but two tunnels may be considered a unidirectional construct, but two tunnels may be
associated to form a bidirectional mechanism. An IPIP tunnel is associated to form a bidirectional mechanism. An IPIP tunnel is
setup as follows. The outer addresses are an ACP address of the Join setup as follows. The outer addresses are an ACP address of the
Proxy, and the ACP address of the Join Registrar. The inner proxy, and the ACP address of the join registrar. The inner
addresses seen in the tunnel are the link-local addresses of the addresses seen in the tunnel are the link-local addresses of the
network on which the join activity is occuring. network on which the join activity is occurring.
One way to look at this construct is to consider that the Registrar One way to look at this construct is to consider that the registrar
is extending attaching an interface to the network on which the Join is extending an interface to attaching to the network on which the
Proxy is physically present. The Registrar then interacts as if it proxy is physically present. The registrar then interacts as if it
were present on that network using link-local (fe80::) addresses. were present on that network using link-local (fe80::) addresses.
The Join node is unaware that the traffic is being proxied through a The registrar is unaware that the traffic is being proxied through a
tunnel, and does not need any special routing. tunnel, and does not need any special routing.
There are a number of considerations with this mechanism which cause There are a number of considerations with this mechanism which cause
some minor amounts of complexity. Note that due to the tunnels, the some minor amounts of complexity. Note that due to the tunnels, the
Registrar sees multiple connections to a fe80::/10 network on not registrar sees multiple connections to a fe80::/10 network on not
just physical interfaces, but on each of the virtual interfaces just physical interfaces, but on each of the virtual interfaces
representing the tunnels. representing the tunnels.
C.1. Multiple Join networks on the Join Proxy side C.1. Multiple Join networks on the Join Proxy side
The Join Proxy will in the general case be a routing device with The proxy will in the general case be a routing device with multiple
multiple interfaces. Even a device as simple as a wifi access point interfaces. Even a device as simple as a wifi access point may have
may have wired, and multiple frequencies of wireless interfaces, wired, and multiple frequencies of wireless interfaces, potentially
potentially with multiple ESSIDs. with multiple ESSIDs.
Each of these interfaces on the Join Proxy may be separate L3 routing Each of these interfaces on the proxy may be separate L3 routing
domains, and therefore will have a unique set of link-local domains, and therefore will have a unique set of link-local
addresses. An IPIP packet being returned by the Registrar needs to addresses. An IPIP packet being returned by the registrar needs to
be forwarded to the correct interface, so the Join Proxy needs an be forwarded to the correct interface, so the proxy needs an
additional key to distinguish which network the packet should be additional key to distinguish which network the packet should be
returned to. returned to.
The simplest way to get this additional key is to allocate an The simplest way to get this additional key is to allocate an
additional ACP address; one address for each network on which join additional ACP address; one address for each network on which join
traffic is occuring. traffic is occurring.
C.2. Automatic configuration of tunnels on Registrar C.2. Automatic configuration of tunnels on Registrar
The Join Proxy is expected to do a GRASP negotiation with the Proxy The proxy is expected to do a GRASP negotiation with the proxy for
for each Join Interface that it needs to relay traffic from. This is each interface that it needs to relay traffic from. This is to
to permit Registrars to configure the appropriate virtual interfaces permit registrars to configure the appropriate virtual interfaces
before join traffic arrives. before traffic arrives.
A Registrar serving a large number of interfaces may not wish to A registrar serving a large number of interfaces may not wish to
allocate resources to every interface at all times, but can instead allocate resources to every interface at all times, but can instead
dynamically allocate interfaces. It can do this by monitoring IPIP dynamically allocate interfaces. It can do this by monitoring IPIP
traffic that arrives on its ACP interface, and when packets arrive traffic that arrives on its ACP interface, and when packets arrive
from new Join Proxys, it can dynamically configure virtual from new proxys, it can dynamically configure virtual interfaces.
interfaces.
A more sophisticated Registrar willing to modify the behaviour of its A more sophisticated registrar willing to modify the behaviour of its
TCP and UDP stack could note the IPIP traffic origination in the TCP and UDP stack could note the IPIP traffic origination in the
socket control block and make information available to the TCP layer socket control block and make information available to the TCP layer
(for HTTPS connections), or to the application (for CoAP connections) (for HTTPS connections), or to the application (for CoAP connections)
via a proprietary extension to the socket API. via a proprietary extension to the socket API.
C.3. Proxy Neighbor Discovery by Join Proxy C.3. Proxy Neighbor Discovery by Join Proxy
The Join Proxy MUST answer neighbor discovery messages for the The proxy MUST answer neighbor discovery messages for the address
address given by the Registrar as being its link-local address. The given by the registrar as being its link-local address. The proxy
Join Proxy must also advertise this address as the address to which must also advertise this address as the address to which to connect
to connect when advertising its existence. when advertising its existence.
This Proxy neighbor discovery means that the Pledge will create TCP This proxy neighbor discovery means that the pledge will create TCP
and UDP connections to the correct Registrar address. This matters and UDP connections to the correct registrar address. This matters
as the TCP and UDP pseudo-header checksum includes the destination as the TCP and UDP pseudo-header checksum includes the destination
address, and for the Proxy to remain completely stateless, it must address, and for the proxy to remain completely stateless, it must
not be necessary for the checksum to be updated. not be necessary for the checksum to be updated.
C.4. Use of connected sockets; or IP_PKTINFO for CoAP on Registrar C.4. Use of connected sockets; or IP_PKTINFO for CoAP on Registrar
TCP connections on the Registrar SHOULD properly capture the ifindex TCP connections on the registrar SHOULD properly capture the ifindex
of the incoming connection into the socket structure. This is normal of the incoming connection into the socket structure. This is normal
IPv6 socket API processing. The outgoing responses will go out on IPv6 socket API processing. The outgoing responses will go out on
the same (virtual) interface by ifindex. the same (virtual) interface by ifindex.
When using UDP sockets with CoAP, the application will have to pay When using UDP sockets with CoAP, the application will have to pay
attention to the incoming ifindex on the socket. Access to this attention to the incoming ifindex on the socket. Access to this
information is available using the IP_PKTINFO auxiliary extension, information is available using the IP_PKTINFO auxiliary extension,
which is a standard part of the IPv6 sockets API [RFC3542]. which is a standard part of the IPv6 sockets API [RFC3542].
A Registrar application could, after receipt of an initial CoAP A registrar application could, after receipt of an initial CoAP
message from the Pledge, create a connected UDP socket (including the message from the pledge, create a connected UDP socket (including the
ifindex information.) The kernel would then take care of accurate ifindex information.) The kernel would then take care of accurate
demultiplexing upon receive, and subsequent transmission to the demultiplexing upon receive, and subsequent transmission to the
correct interface. correct interface.
C.5. Use of socket extension rather than virtual interface C.5. Use of socket extension rather than virtual interface
Some operating systems on which a Registrar needs to be implemented Some operating systems on which a registrar needs to be implemented
may find need for a virtual interface per Join Proxy to be may find need for a virtual interface per proxy to be problematic.
problematic. There are other mechanisms which can be implemented. There are other mechanisms which can be implemented.
If the IPIP decapsulator can mark the (SYN) packet inside the kernel If the IPIP decapsulator can mark the (SYN) packet inside the kernel
with the address of the Join Proxy sending the traffic, then an with the address of the proxy sending the traffic, then an interface
interface per Join Proxy may not be needed. The outgoing path need per proxy may not be needed. The outgoing path need just pay
just pay attention to this extra information and add an appropriate attention to this extra information and add an appropriate IPIP
IPIP header on outgoing. A CoAP over UDP mechanism may need to header on outgoing. A CoAP over UDP mechanism may need to expose
expose this extra information to the application as the UDP sockets this extra information to the application as the UDP sockets are
are often not connected, and the application will need to specify the often not connected, and the application will need to specify the
outgoing path on each packet sent. outgoing path on each packet sent.
Such an additional socket mechanism has not been standardized. Such an additional socket mechanism has not been standardized.
Terminating L2TP connections over IPsec transport mode suffers from Terminating L2TP connections over IPsec transport mode suffers from
the same challenges. the same challenges.
Appendix D. MUD Extension Appendix D. MUD Extension
The following extension augments the MUD model to include a single The following extension augments the MUD model to include a single
node, as described in [I-D.ietf-opsawg-mud] section 3.6, using the node, as described in [I-D.ietf-opsawg-mud] section 3.6, using the
skipping to change at page 70, line 5 skipping to change at page 72, line 49
MASA URL."; MASA URL.";
leaf masa-server { leaf masa-server {
type inet:uri; type inet:uri;
description description
"This value is the URI of the MASA server"; "This value is the URI of the MASA server";
} }
} }
} }
<CODE ENDS> <CODE ENDS>
The MUD extensions string "masa" is defined, and MUST be included in
the extensions array of the mud container of a MUD file when this
extension is used.
Appendix E. Example Vouchers Appendix E. Example Vouchers
Three entities are involved in a voucher: the MASA issues (signs) it, Three entities are involved in a voucher: the MASA issues (signs) it,
the Registrar's public key is mentioned in the voucher, and the the registrar's public key is mentioned in the voucher, and the
Pledge validates it. In order to provide reproduceable examples the pledge validates it. In order to provide reproduceable examples the
public and private keys for an example MASA and Registrar are first public and private keys for an example MASA and registrar are first
listed. listed.
E.1. Keys involved E.1. Keys involved
The Manufacturer has a Certificate Authority that signs the Pledge's The Manufacturer has a Certificate Authority that signs the pledge's
IDevID. In addition the Manufacturer's signing authority (the MASA) IDevID. In addition the Manufacturer's signing authority (the MASA)
signs the vouchers, and that certificate must distributed to the signs the vouchers, and that certificate must distributed to the
devices at manufacturing time so that vouchers can be validated. devices at manufacturing time so that vouchers can be validated.
E.1.1. MASA key pair for voucher signatures E.1.1. MASA key pair for voucher signatures
This private key signs vouchers: This private key signs vouchers:
-----BEGIN EC PRIVATE KEY----- -----BEGIN EC PRIVATE KEY-----
MIGkAgEBBDAgiRoYqKoEcfOfvRvmZ5P5Azn58tuI7nSnIy7OgFnCeiNo+BmbgMho MIGkAgEBBDAgiRoYqKoEcfOfvRvmZ5P5Azn58tuI7nSnIy7OgFnCeiNo+BmbgMho
skipping to change at page 71, line 29 skipping to change at page 74, line 29
BgNVBAMMDVVuc3RydW5nIE1BU0EwdjAQBgcqhkjOPQIBBgUrgQQAIgNiAATZAH3R BgNVBAMMDVVuc3RydW5nIE1BU0EwdjAQBgcqhkjOPQIBBgUrgQQAIgNiAATZAH3R
b2FvIJOnts+vXuWW35ofyNbCHzjAzOi2kWZFE1ByurKImNcNMFGirGnRXIXGqWCf b2FvIJOnts+vXuWW35ofyNbCHzjAzOi2kWZFE1ByurKImNcNMFGirGnRXIXGqWCf
w5ICgJ8CuM3vV5ty9bf7KUlOkejzTvv+5PV++elkP9HQ83vqTAws2WwWTxKjEDAO w5ICgJ8CuM3vV5ty9bf7KUlOkejzTvv+5PV++elkP9HQ83vqTAws2WwWTxKjEDAO
MAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDZwAwZAIwGb0oyM0doP6t3/LSPL5O MAwGA1UdEwEB/wQCMAAwCgYIKoZIzj0EAwIDZwAwZAIwGb0oyM0doP6t3/LSPL5O
DuatEwMYh7WGO+IYTHC8K7EyHBOmCYReKT2+GhV/CLWzAjBNy6UMJTt1tsxJsJqd DuatEwMYh7WGO+IYTHC8K7EyHBOmCYReKT2+GhV/CLWzAjBNy6UMJTt1tsxJsJqd
MPUIFj+4wZg1AOIb/JoA6M7r33pwLQTrHRxEzVMGfWOkYUw= MPUIFj+4wZg1AOIb/JoA6M7r33pwLQTrHRxEzVMGfWOkYUw=
-----END CERTIFICATE----- -----END CERTIFICATE-----
E.1.3. Registrar key pair E.1.3. Registrar key pair
The Registrar key (or chain) is the representative of the domain The registrar key (or chain) is the representative of the domain
owner. This key signs Registrar voucher-requests: owner. This key signs registrar voucher-requests:
-----BEGIN EC PRIVATE KEY----- -----BEGIN EC PRIVATE KEY-----
MHcCAQEEIF+obiToYYYeMifPsZvrjWJ0yFsCJwIFhpokmT/TULmXoAoGCCqGSM49 MHcCAQEEIF+obiToYYYeMifPsZvrjWJ0yFsCJwIFhpokmT/TULmXoAoGCCqGSM49
AwEHoUQDQgAENWQOzcNMUjP0NrtfeBc0DJLWfeMGgCFdIv6FUz4DifM1ujMBec/g AwEHoUQDQgAENWQOzcNMUjP0NrtfeBc0DJLWfeMGgCFdIv6FUz4DifM1ujMBec/g
6W/P6boTmyTGdFOh/8HwKUerL5bpneK8sg== 6W/P6boTmyTGdFOh/8HwKUerL5bpneK8sg==
-----END EC PRIVATE KEY----- -----END EC PRIVATE KEY-----
The public key is indicated in a Pledge voucher-request to show The public key is indicated in a pledge voucher-request to show
proximity. proximity.
-----BEGIN CERTIFICATE----- -----BEGIN CERTIFICATE-----
MIIBrjCCATOgAwIBAgIBAzAKBggqhkjOPQQDAzBOMRIwEAYKCZImiZPyLGQBGRYC MIIBrjCCATOgAwIBAgIBAzAKBggqhkjOPQQDAzBOMRIwEAYKCZImiZPyLGQBGRYC
Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHTAbBgNVBAMMFFVuc3RydW5n Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHTAbBgNVBAMMFFVuc3RydW5n
IEZvdW50YWluIENBMB4XDTE3MDkwNTAxMTI0NVoXDTE5MDkwNTAxMTI0NVowQzES IEZvdW50YWluIENBMB4XDTE3MDkwNTAxMTI0NVoXDTE5MDkwNTAxMTI0NVowQzES
MBAGCgmSJomT8ixkARkWAmNhMRkwFwYKCZImiZPyLGQBGRYJc2FuZGVsbWFuMRIw MBAGCgmSJomT8ixkARkWAmNhMRkwFwYKCZImiZPyLGQBGRYJc2FuZGVsbWFuMRIw
EAYDVQQDDAlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQ1ZA7N EAYDVQQDDAlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggqhkjOPQMBBwNCAAQ1ZA7N
w0xSM/Q2u194FzQMktZ94waAIV0i/oVTPgOJ8zW6MwF5z+Dpb8/puhObJMZ0U6H/ w0xSM/Q2u194FzQMktZ94waAIV0i/oVTPgOJ8zW6MwF5z+Dpb8/puhObJMZ0U6H/
wfApR6svlumd4ryyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMDA2kAMGYCMQC3 wfApR6svlumd4ryyow0wCzAJBgNVHRMEAjAAMAoGCCqGSM49BAMDA2kAMGYCMQC3
/iTQJ3evYYcgbXhbmzrp64t3QC6qjIeY2jkDx062nuNifVKtyaara3F30AIkKSEC /iTQJ3evYYcgbXhbmzrp64t3QC6qjIeY2jkDx062nuNifVKtyaara3F30AIkKSEC
MQDi29efbTLbdtDk3tecY/rD7V77XaJ6nYCmdDCR54TrSFNLgxvt1lyFM+0fYpYR MQDi29efbTLbdtDk3tecY/rD7V77XaJ6nYCmdDCR54TrSFNLgxvt1lyFM+0fYpYR
c3o= c3o=
-----END CERTIFICATE----- -----END CERTIFICATE-----
The Registrar public certificate as decoded by openssl's x509 The registrar public certificate as decoded by openssl's x509
utility. Note that the Registrar certificate is marked with the utility. Note that the registrar certificate is marked with the
cmcRA extension. cmcRA extension.
Certificate: Certificate:
Data: Data:
Version: 3 (0x2) Version: 3 (0x2)
Serial Number: 3 (0x3) Serial Number: 3 (0x3)
Signature Algorithm: ecdsa-with-SHA384 Signature Algorithm: ecdsa-with-SHA384
Issuer: DC = ca, DC = sandelman, CN = Unstrung Fount Issuer: DC = ca, DC = sandelman, CN = Unstrung Fount
ain CA ain CA
Validity Validity
skipping to change at page 73, line 7 skipping to change at page 76, line 7
9e:e3:62:7d:52:ad:c9:a6:ab:6b:71:77:d0:02:24:29:21: 9e:e3:62:7d:52:ad:c9:a6:ab:6b:71:77:d0:02:24:29:21:
02: 02:
31:00:e2:db:d7:9f:6d:32:db:76:d0:e4:de:d7:9c:63:fa: 31:00:e2:db:d7:9f:6d:32:db:76:d0:e4:de:d7:9c:63:fa:
c3: c3:
ed:5e:fb:5d:a2:7a:9d:80:a6:74:30:91:e7:84:eb:48:53: ed:5e:fb:5d:a2:7a:9d:80:a6:74:30:91:e7:84:eb:48:53:
4b: 4b:
83:1b:ed:d6:5c:85:33:ed:1f:62:96:11:73:7a 83:1b:ed:d6:5c:85:33:ed:1f:62:96:11:73:7a
E.1.4. Pledge key pair E.1.4. Pledge key pair
The Pledge has an IDevID key pair built in at manufacturing time: The pledge has an IDevID key pair built in at manufacturing time:
-----BEGIN EC PRIVATE KEY----- -----BEGIN EC PRIVATE KEY-----
MHcCAQEEIL+ue8PQcN+M7LFBGPsompYwobI/rsoHnTb2a+0hO+8joAoGCCqGSM49 MHcCAQEEIL+ue8PQcN+M7LFBGPsompYwobI/rsoHnTb2a+0hO+8joAoGCCqGSM49
AwEHoUQDQgAEumBVaDlX87WyME8CJToyt9NWy6sYw0DTbjjJIn79pgr7ALa//Y8p AwEHoUQDQgAEumBVaDlX87WyME8CJToyt9NWy6sYw0DTbjjJIn79pgr7ALa//Y8p
r70WpK1SIaiUeeFw7e+lCzTp1Z+wJu14Bg== r70WpK1SIaiUeeFw7e+lCzTp1Z+wJu14Bg==
-----END EC PRIVATE KEY----- -----END EC PRIVATE KEY-----
The public key is used by the Registrar to find the MASA. The MASA The public key is used by the registrar to find the MASA. The MASA
URL is in an extension described in Section 2.3. RFC-EDITOR: Note URL is in an extension described in Section 2.3. RFC-EDITOR: Note
that these certificates are using a Private Enterprise Number for the that these certificates are using a Private Enterprise Number for the
not-yet-assigned by IANA MASA URL, and need to be replaced before not-yet-assigned by IANA MASA URL, and need to be replaced before
AUTH48. AUTH48.
-----BEGIN CERTIFICATE----- -----BEGIN CERTIFICATE-----
MIICMjCCAbegAwIBAgIBDDAKBggqhkjOPQQDAjBNMRIwEAYKCZImiZPyLGQBGRYC MIICMjCCAbegAwIBAgIBDDAKBggqhkjOPQQDAjBNMRIwEAYKCZImiZPyLGQBGRYC
Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHDAaBgNVBAMME1Vuc3RydW5n Y2ExGTAXBgoJkiaJk/IsZAEZFglzYW5kZWxtYW4xHDAaBgNVBAMME1Vuc3RydW5n
IEhpZ2h3YXkgQ0EwIBcNMTcxMDEyMTM1MjUyWhgPMjk5OTEyMzEwMDAwMDBaMEsx IEhpZ2h3YXkgQ0EwIBcNMTcxMDEyMTM1MjUyWhgPMjk5OTEyMzEwMDAwMDBaMEsx
EjAQBgoJkiaJk/IsZAEZFgJjYTEZMBcGCgmSJomT8ixkARkWCXNhbmRlbG1hbjEa EjAQBgoJkiaJk/IsZAEZFgJjYTEZMBcGCgmSJomT8ixkARkWCXNhbmRlbG1hbjEa
MBgGA1UEAwwRMDAtRDAtRTUtRjItMDAtMDIwWTATBgcqhkjOPQIBBggqhkjOPQMB MBgGA1UEAwwRMDAtRDAtRTUtRjItMDAtMDIwWTATBgcqhkjOPQIBBggqhkjOPQMB
BwNCAARJp5i0dU1aUnR2u8wMRwgkNupNbNM7m1n0mj+0KJZjcPIqID+trPjTSobt BwNCAARJp5i0dU1aUnR2u8wMRwgkNupNbNM7m1n0mj+0KJZjcPIqID+trPjTSobt
uIdpRPfGZ8hU/nIUveqwyoYI8BPbo4GHMIGEMB0GA1UdDgQWBBQdMRZhthFQmzz6 uIdpRPfGZ8hU/nIUveqwyoYI8BPbo4GHMIGEMB0GA1UdDgQWBBQdMRZhthFQmzz6
E7YVXzkL7XZDKjAJBgNVHRMEAjAAMCsGA1UdEQQkMCKgIAYJKwYBBAGC7lIBoBMM E7YVXzkL7XZDKjAJBgNVHRMEAjAAMCsGA1UdEQQkMCKgIAYJKwYBBAGC7lIBoBMM
ETAwLUQwLUU1LUYyLTAwLTAyMCsGCSsGAQQBgu5SAgQeDBxodHRwczovL2hpZ2h3 ETAwLUQwLUU1LUYyLTAwLTAyMCsGCSsGAQQBgu5SAgQeDBxodHRwczovL2hpZ2h3
YXkuc2FuZGVsbWFuLmNhMAoGCCqGSM49BAMCA2kAMGYCMQDhJ1N+eanW1U/e5qoM YXkuc2FuZGVsbWFuLmNhMAoGCCqGSM49BAMCA2kAMGYCMQDhJ1N+eanW1U/e5qoM
SGvUvWHR7uic8cJbh7vXy580nBs8bpNn60k/+IzvEUetMzICMQCr1uxvdYeKq7mb SGvUvWHR7uic8cJbh7vXy580nBs8bpNn60k/+IzvEUetMzICMQCr1uxvdYeKq7mb
RXCR4ZCJsw67fJ7jyXZbCUSir+3wBT2+lWggzPDRgYB5ABb7sAw= RXCR4ZCJsw67fJ7jyXZbCUSir+3wBT2+lWggzPDRgYB5ABb7sAw=
-----END CERTIFICATE----- -----END CERTIFICATE-----
The Pledge public certificate as decoded by openssl's x509 utility so The pledge public certificate as decoded by openssl's x509 utility so
that the extensions can be seen. A second custom Extension is that the extensions can be seen. A second custom Extension is
included to provided to contain the EUI48/EUI64 that the Pledge will included to provided to contain the EUI48/EUI64 that the pledge will
configure. configure.
Certificate: Certificate:
Data: Data:
Version: 3 (0x2) Version: 3 (0x2)
Serial Number: 12 (0xc) Serial Number: 12 (0xc)
Signature Algorithm: ecdsa-with-SHA256 Signature Algorithm: ecdsa-with-SHA256
Issuer: DC = ca, DC = sandelman, CN = Unstrung Highw Issuer: DC = ca, DC = sandelman, CN = Unstrung Highw
ay CA ay CA
Validity Validity
skipping to change at page 74, line 49 skipping to change at page 77, line 49
be: be:
95:68:20:cc:f0:d1:81:80:79:00:16:fb:b0:0c 95:68:20:cc:f0:d1:81:80:79:00:16:fb:b0:0c
E.2. Example process E.2. Example process
RFC-EDITOR: these examples will need to be replaced with CMS versions RFC-EDITOR: these examples will need to be replaced with CMS versions
once IANA has assigned the eContentType in [I-D.ietf-anima-voucher]. once IANA has assigned the eContentType in [I-D.ietf-anima-voucher].
E.2.1. Pledge to Registrar E.2.1. Pledge to Registrar
As described in Section 5.2, the Pledge will sign a Pledge voucher- As described in Section 5.2, the pledge will sign a pledge voucher-
request containing the Registrar's public key in the proximity- request containing the registrar's public key in the proximity-
registrar-cert field. The base64 has been wrapped at 60 characters registrar-cert field. The base64 has been wrapped at 60 characters
for presentation reasons. for presentation reasons.
MIIHHAYJKoZIhvcNAQcCoIIHDTCCBwkCAQExDzANBglghkgBZQMEAgEFADCC MIIHHAYJKoZIhvcNAQcCoIIHDTCCBwkCAQExDzANBglghkgBZQMEAgEFADCC
Aw4GCSqGSIb3DQEHAaCCAv8EggL7eyJpZXRmLXZvdWNoZXItcmVxdWVzdDp2 Aw4GCSqGSIb3DQEHAaCCAv8EggL7eyJpZXRmLXZvdWNoZXItcmVxdWVzdDp2
b3VjaGVyIjp7ImFzc2VydGlvbiI6InByb3hpbWl0eSIsImNyZWF0ZWQtb24i b3VjaGVyIjp7ImFzc2VydGlvbiI6InByb3hpbWl0eSIsImNyZWF0ZWQtb24i
OiIyMDE3LTA5LTAxIiwic2VyaWFsLW51bWJlciI6IjAwLUQwLUU1LUYyLTAw OiIyMDE3LTA5LTAxIiwic2VyaWFsLW51bWJlciI6IjAwLUQwLUU1LUYyLTAw
LTAyIiwibm9uY2UiOiJEc3M5OXNCcjNwTk1PQUNlLUxZWTd3IiwicHJveGlt LTAyIiwibm9uY2UiOiJEc3M5OXNCcjNwTk1PQUNlLUxZWTd3IiwicHJveGlt
aXR5LXJlZ2lzdHJhci1jZXJ0IjoiTUlJQnJqQ0NBVE9nQXdJQkFnSUJBekFL aXR5LXJlZ2lzdHJhci1jZXJ0IjoiTUlJQnJqQ0NBVE9nQXdJQkFnSUJBekFL
QmdncWhrak9QUVFEQXpCT01SSXdFQVlLQ1pJbWlaUHlMR1FCR1JZQ1kyRXhH QmdncWhrak9QUVFEQXpCT01SSXdFQVlLQ1pJbWlaUHlMR1FCR1JZQ1kyRXhH
skipping to change at page 80, line 21 skipping to change at page 83, line 21
MTI0NVowQzESMBAGCgmSJomT8ixkARkWAmNhMRkwFwYKCZImiZPyLGQBGRYJ MTI0NVowQzESMBAGCgmSJomT8ixkARkWAmNhMRkwFwYKCZImiZPyLGQBGRYJ
c2FuZGVsbWFuMRIwEAYDVQQDDAlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggq c2FuZGVsbWFuMRIwEAYDVQQDDAlsb2NhbGhvc3QwWTATBgcqhkjOPQIBBggq
hkjOPQMBBwNCAAQ1ZA7Nw0xSM/Q2u194FzQMktZ94waAIV0i/oVTPgOJ8zW6 hkjOPQMBBwNCAAQ1ZA7Nw0xSM/Q2u194FzQMktZ94waAIV0i/oVTPgOJ8zW6
MwF5z+Dpb8/puhObJMZ0U6H/wfApR6svlumd4ryyow0wCzAJBgNVHRMEAjAA MwF5z+Dpb8/puhObJMZ0U6H/wfApR6svlumd4ryyow0wCzAJBgNVHRMEAjAA
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E.2.2. Registrar to MASA E.2.2. Registrar to MASA
As described in Section 5.4 the Registrar will sign a Registrar As described in Section 5.4 the registrar will sign a registrar
voucher-request, and will include Pledge's voucher request in the voucher-request, and will include pledge's voucher request in the
prior-signed-voucher-request. prior-signed-voucher-request.
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skipping to change at page 86, line 15 skipping to change at page 89, line 15
3465:d=5 hl=2 l= 10 cons: SEQUENCE 3465:d=5 hl=2 l= 10 cons: SEQUENCE
3467:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-S 3467:d=6 hl=2 l= 8 prim: OBJECT :ecdsa-with-S
HA256 HA256
3477:d=5 hl=2 l= 71 prim: OCTET STRING [HEX DUMP]:30 3477:d=5 hl=2 l= 71 prim: OCTET STRING [HEX DUMP]:30
4502200DDA79B8F52530AA7B1854000FBCA9020A85BFCABE2A426DE9CDCE 4502200DDA79B8F52530AA7B1854000FBCA9020A85BFCABE2A426DE9CDCE
EE2569548F02210083D6EF019318A9BE2830BC80E659F8E561D27172FA33 EE2569548F02210083D6EF019318A9BE2830BC80E659F8E561D27172FA33
3637DFAB98F750783B46 3637DFAB98F750783B46
E.2.3. MASA to Registrar E.2.3. MASA to Registrar
The MASA will return a voucher to the Registrar, to be relayed to the The MASA will return a voucher to the registrar, to be relayed to the
Pledge. pledge.
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