draft-ietf-anima-bootstrapping-keyinfra-00.txt   draft-ietf-anima-bootstrapping-keyinfra-01.txt 
ANIMA WG M. Pritikin ANIMA WG M. Pritikin
Internet-Draft Cisco Internet-Draft Cisco
Intended status: Informational M. Richardson Intended status: Informational M. Richardson
Expires: February 27, 2016 SSW Expires: April 20, 2016 SSW
M. Behringer M. Behringer
S. Bjarnason S. Bjarnason
Cisco Cisco
August 26, 2015 October 18, 2015
Bootstrapping Key Infrastructures Bootstrapping Key Infrastructures
draft-ietf-anima-bootstrapping-keyinfra-00 draft-ietf-anima-bootstrapping-keyinfra-01
Abstract Abstract
This document specifies automated bootstrapping of an key This document specifies automated bootstrapping of an key
infrastructure using vendor installed IEEE 802.1AR manufacturing infrastructure using vendor installed IEEE 802.1AR manufacturing
installed certificates, in combination with a vendor based service on installed certificates, in combination with a vendor based service on
the Internet. Before being authenticated, a new device has only the Internet. Before being authenticated, a new device has only
link-local connectivity, and does not require a routable address. link-local connectivity, and does not require a routable address.
When a vendor provides an Internet based service, devices can be When a vendor provides an Internet based service, devices can be
forced to join only specific domains but in limited/disconnected forced to join only specific domains but in limited/disconnected
skipping to change at page 1, line 42 skipping to change at page 1, line 42
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
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 February 27, 2016. This Internet-Draft will expire on April 20, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the Copyright (c) 2015 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
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Architectural Overview . . . . . . . . . . . . . . . . . . . 5 2. Architectural Overview . . . . . . . . . . . . . . . . . . . 5
3. Functional Overview . . . . . . . . . . . . . . . . . . . . . 6 3. Functional Overview . . . . . . . . . . . . . . . . . . . . . 7
3.1. Behavior of a new entity . . . . . . . . . . . . . . . . 7 3.1. Behavior of a new entity . . . . . . . . . . . . . . . . 9
3.1.1. Discovery and Identity . . . . . . . . . . . . . . . 9 3.1.1. Discovery . . . . . . . . . . . . . . . . . . . . . . 11
3.1.2. Imprint . . . . . . . . . . . . . . . . . . . . . . . 10 3.1.2. Identity . . . . . . . . . . . . . . . . . . . . . . 12
3.1.3. Enrollment . . . . . . . . . . . . . . . . . . . . . 11 3.1.3. Request Join . . . . . . . . . . . . . . . . . . . . 12
3.1.4. Being Managed . . . . . . . . . . . . . . . . . . . . 12 3.1.4. Imprint . . . . . . . . . . . . . . . . . . . . . . . 13
3.2. Behavior of a proxy . . . . . . . . . . . . . . . . . . . 12 3.1.5. Enrollment . . . . . . . . . . . . . . . . . . . . . 14
3.3. Behavior of the Registrar . . . . . . . . . . . . . . . . 12 3.1.6. Being Managed . . . . . . . . . . . . . . . . . . . . 14
3.3.1. Entity Authentication . . . . . . . . . . . . . . . . 13 3.2. Behavior of a proxy . . . . . . . . . . . . . . . . . . . 15
3.3.2. Entity Authorization . . . . . . . . . . . . . . . . 13 3.3. Behavior of the Registrar (Bootstrap Server) . . . . . . 15
3.3.3. Claiming the New Entity . . . . . . . . . . . . . . . 14 3.3.1. Entity Authentication . . . . . . . . . . . . . . . . 16
3.3.4. Log Verification . . . . . . . . . . . . . . . . . . 15 3.3.2. Entity Authorization . . . . . . . . . . . . . . . . 16
3.3.5. Forwarding Authorization Token plus Configuration . . 15 3.3.3. Claiming the New Entity . . . . . . . . . . . . . . . 17
3.4. Behavior of the MASA Service . . . . . . . . . . . . . . 16 3.3.4. Log Verification . . . . . . . . . . . . . . . . . . 18
3.4.1. Issue Authorization Token and Log the event . . . . . 16 3.3.5. Forwarding Audit Token plus Configuration . . . . . . 18
3.4.2. Retrieve Audit Entries from Log . . . . . . . . . . . 16 3.4. Behavior of the MASA Service . . . . . . . . . . . . . . 19
3.5. Leveraging the new key infrastructure / next steps . . . 16 3.4.1. Issue Authorization Token and Log the event . . . . . 19
3.5.1. Network boundaries . . . . . . . . . . . . . . . . . 17 3.4.2. Retrieve Audit Entries from Log . . . . . . . . . . . 19
4. Domain Operator Activities . . . . . . . . . . . . . . . . . 17 3.5. Leveraging the new key infrastructure / next steps . . . 20
4.1. Instantiating the Domain Certification Authority . . . . 17 3.5.1. Network boundaries . . . . . . . . . . . . . . . . . 20
4.2. Instantiating the Registrar . . . . . . . . . . . . . . . 17 3.6. Interactions with Network Access Control . . . . . . . . 20
4.3. Accepting New Entities . . . . . . . . . . . . . . . . . 17 4. Domain Operator Activities . . . . . . . . . . . . . . . . . 20
4.4. Automatic Enrolment of Devices . . . . . . . . . . . . . 18 4.1. Instantiating the Domain Certification Authority . . . . 21
4.5. Secure Network Operations . . . . . . . . . . . . . . . . 19 4.2. Instantiating the Registrar . . . . . . . . . . . . . . . 21
5. Protocol Details . . . . . . . . . . . . . . . . . . . . . . 19 4.3. Accepting New Entities . . . . . . . . . . . . . . . . . 21
5.1. EAP-EST . . . . . . . . . . . . . . . . . . . . . . . . . 20 4.4. Automatic Enrollment of Devices . . . . . . . . . . . . . 22
5.2. Request bootstrap token . . . . . . . . . . . . . . . . . 20 4.5. Secure Network Operations . . . . . . . . . . . . . . . . 22
5.3. Request MASA authorization token . . . . . . . . . . . . 21 5. Protocol Details . . . . . . . . . . . . . . . . . . . . . . 23
5.4. Basic Configuration Information Package . . . . . . . . . 22 5.1. Request Audit Token . . . . . . . . . . . . . . . . . . . 25
5.5. Request MASA authorization log . . . . . . . . . . . . . 22 5.2. Request Audit Token from MASA . . . . . . . . . . . . . . 26
6. Reduced security operational modes . . . . . . . . . . . . . 23 5.3. Basic Configuration Information Package . . . . . . . . . 28
6.1. New Entity security reductions . . . . . . . . . . . . . 23 5.4. Request MASA authorization log . . . . . . . . . . . . . 28
6.2. Registrar security reductions . . . . . . . . . . . . . . 24 6. Reduced security operational modes . . . . . . . . . . . . . 29
6.3. MASA security reductions . . . . . . . . . . . . . . . . 24 6.1. New Entity security reductions . . . . . . . . . . . . . 29
7. Security Considerations . . . . . . . . . . . . . . . . . . . 25 6.2. Registrar security reductions . . . . . . . . . . . . . . 29
7.1. Trust Model . . . . . . . . . . . . . . . . . . . . . . . 26 6.3. MASA security reductions . . . . . . . . . . . . . . . . 30
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 26 7. Security Considerations . . . . . . . . . . . . . . . . . . . 30
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 26 7.1. Trust Model . . . . . . . . . . . . . . . . . . . . . . . 32
9.1. Normative References . . . . . . . . . . . . . . . . . . 26 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 32
9.2. Informative References . . . . . . . . . . . . . . . . . 26 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 32
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27 9.1. Normative References . . . . . . . . . . . . . . . . . . 32
9.2. Informative References . . . . . . . . . . . . . . . . . 32
Appendix A. Editor notes . . . . . . . . . . . . . . . . . . . . 33
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 34
1. Introduction 1. Introduction
To literally "pull yourself up by the bootstraps" is an impossible To literally "pull yourself up by the bootstraps" is an impossible
action. Similarly the secure establishment of a key infrastructure action. Similarly the secure establishment of a key infrastructure
without external help is also an impossibility. Today it is accepted without external help is also an impossibility. Today it is accepted
that the initial connections between nodes are insecure, until key that the initial connections between nodes are insecure, until key
distribution is complete, or that domain-specific keying material is distribution is complete, or that domain-specific keying material is
pre-provisioned on each new device in a costly and non-scalable pre-provisioned on each new device in a costly and non-scalable
manner. This document describes a zero-touch approach to manner. This document describes a zero-touch approach to
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decisions are based on the new entity's authenticated identity, as decisions are based on the new entity's authenticated identity, as
established by verification of previously installed credentials such established by verification of previously installed credentials such
as a manufacturer installed IEEE 802.1AR certificate, and verified as a manufacturer installed IEEE 802.1AR certificate, and verified
back-end information such as a configured list of purchased devices back-end information such as a configured list of purchased devices
or communication with a trusted third-party. The new entity's or communication with a trusted third-party. The new entity's
decisions are made according to verified communication with a trusted decisions are made according to verified communication with a trusted
third-party or in a strictly auditable fasion. third-party or in a strictly auditable fasion.
Optimal security is achieved with IEEE 802.1AR certificates on each Optimal security is achieved with IEEE 802.1AR certificates on each
new entity, accompanied by a third-party Internet based service for new entity, accompanied by a third-party Internet based service for
verification. The concept also works with less requirements, but is verification. Bootstrapping concepts run to completion with less
then less secure. A domain can choose to accept lower levels of requirements, but are then less secure. A domain can choose to
security when a trusted third-party is not available so that accept lower levels of security when a trusted third-party is not
bootstrapping proceeds even at the risk of reduced security. Only available so that bootstrapping proceeds even at the risk of reduced
the domain can make these decisions based on administrative input and security. Only the domain can make these decisions based on
known behavior of the new entity. administrative input and known behavior of the new entity.
The result of bootstrapping is that a domain specific key The result of bootstrapping is that a domain specific key
infrastructure is deployed. Since IEEE 802.1AR PKI certificates are infrastructure is deployed. Since IEEE 802.1AR PKI certificates are
used for identifying the new entity and the public key of the domain used for identifying the new entity, and the public key of the domain
identity is leveraged during communiciations with an Internet based identity is leveraged during communiciations with an Internet based
service, which is itself authenticated using HTTPS, bootstrapping of service, which is itself authenticated using HTTPS, bootstrapping of
a domain specific Public Key Infrastructure (PKI) is fully described. a domain specific Public Key Infrastructure (PKI) is described.
Sufficient agility to support bootstrapping alternative key Sufficient agility to support bootstrapping alternative key
infrastructures (such as symmetric key solutions) is considered infrastructures (such as symmetric key solutions) is considered
although no such key infrastructure is described. although no such alternate key infrastructure is described.
1.1. Terminology 1.1. 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:
Domain Identity: The domain identity is the 160-bit SHA-1 hash of DomainID: The domain identity is the 160-bit SHA-1 hash of the BIT
the BIT STRING of the subjectPublicKey of the domain trust anchor STRING of the subjectPublicKey of the domain trust anchor that is
that is stored by the Domain CA. This is consistent with the stored by the Domain CA. This is consistent with the RFC5280
RFC5280 Certification Authority subject key identifier of the Certification Authority subject key identifier of the Domain CA's
Domain CA's self signed root certificate. (A string value bound self signed root certificate. (A string value bound to the Domain
to the Domain CA's self signed root certificate subject and issuer CA's self signed root certificate subject and issuer fields is
fields is often colloquially used as a humanized identity value often colloquially used as a humanized identity value but during
but during protocol discussions the more exact term as defined protocol discussions the more exact term as defined here is used).
here is used).
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 that wishes to join a network imprint: the process where a device that wishes to join a network
acquires it's domain specific identity. This term is taken from acquires it's domain specific identity. This term is taken from
Konrad Lorenz's work in biology with new ducklings: during a Konrad Lorenz's work in biology with new ducklings: during a
critical period, the duckling would assume that anything that critical period, the duckling would assume that anything that
looks like a mother duck is in fact their mother. [imprinting] looks like a mother duck is in fact their mother. [imprinting]
pledge the prospective device, which has the identity provided to at pledge: the prospective device, which has the identity provided to
the factory. Neither the device nor the network knows if the at the factory. Neither the device nor the network knows if the
device yet knows if this device belongs with this network. This device yet knows if this device belongs with this network. This
is definition 6, according to [pledge] is definition 6, according to [pledge]
Audit Token: A signed token from the manufacturer authorized signing
authority indicating that the bootstrapping event has been
successfully logged. This has been referred to as an
"authorization token" indicating that it authorizes bootstrapping
to proceed.
Ownership Voucher: A signed voucher from the vendor vouching that a
specific domain "owns" the new entity.
2. Architectural Overview 2. Architectural Overview
The logical elements of the bootstrapping framework are described in The logical elements of the bootstrapping framework are described in
this section. Figure 1 provides a simplified overview of the this section. Figure 1 provides a simplified overview of the
components. Each component is logical and may be combined with other components. Each component is logical and may be combined with other
components as necessary. components as necessary.
Vendor components .
. .+------------------------+
.+---------------+ +--------------Drop Ship-------------->.| Vendor Service |
+--------------Drop Ship------------------------.| Manufacturer | | .+------------------------+
| .+---------------+ | .| M anufacturer| |
| .| M anufacturer | | .| A uthorized |Ownership|
| .| A uthorized | | .| S igning |Tracker |
| .| S igning | | .| A uthority | |
| .| A uthority | | .+--------------+---------+
| .+---------------+ | .............. ^
V ...... ^ V |
+-------+ | +-------+ ............................................|...
| New | +------------+ +-----------+ | | | . | .
| Entity|<--L2-->| Proxy |<----->| | | | | . +------------+ +-----------+ | .
| | +------------+ | | | | | . | | | | | .
| | | Registrar | | | <---L2---> | | <-------+ .
| | | | | | | or | Proxy | | Registrar | .
| |<-----L3---------------------( may proxy )---------+ | <---L3---> <---L3--> | .
| | +-----------+ | New | . | | | | .
| | | | Entity| . +------------+ +-----+-----+ .
| | +----------------------------+ | | . | .
| |<-----Enroll---->| Domain Certification | ^ | | . +-----------------+----------+ .
| |<-----Config---->| Authority | . | | . | Domain Certification | .
+-------+ . | Management and etc | . | | . | Authority | .
. +----------------------------+ . +-------+ . | Management and etc | .
. . . +----------------------------+ .
......................................... . .
"domain" components ................................................
"Domain" components
Figure 1 Figure 1
Domain: The set of entities that trust a common key infrastructure Domain: The set of entities that trust a common key infrastructure
trust anchor. trust anchor. This includes the Proxy, Registrar, Domain
Certificate Authority, Management components and any existing
entity that is already a 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 the Registrar and stores provides certification functionalities to the Registrar and stores
the trust anchor that defines the domain. Optionally, it the trust anchor that defines the domain. Optionally, it
certifies all elements. certifies all elements.
Registrar: A representative of the domain that is configured, Registrar: A representative of the domain that is configured,
perhaps autonomically, to decide whether a new device is allowed perhaps autonomically, to decide whether a new device is allowed
to join the domain. The administrator of the domain interfaces to join the domain. The administrator of the domain interfaces
with a Registrar to control this process. Typically a Registrar with a Registrar to control this process. Typically a Registrar
is "inside" its domain. is "inside" its domain.
New Entity: A new device or virtual machine or software component New Entity: A new device or virtual machine or software component
that is not yet part of the domain. that is not yet part of the domain.
Proxy: A domain entity that helps the New Entity join the domain. A Proxy: A domain entity that helps the New Entity join the domain. A
Proxy facilitates communication for devices that find themselves Proxy facilitates communication for devices that find themselves
in an environment where they are not provided L3 connectivity in an environment where they are not provided connectivity until
until after they are validated as members of the domain. after they are validated as members of the domain. The New Entity
is unaware that they are communicating with a proxy rather than
directly with the Registrar.
MASA Service: A Manufacturer Authorized Signing Authority (MASA) MASA Service: A Manufacturer Authorized Signing Authority (MASA)
service on the global Internet. At a minimum the MASA provides a service on the global Internet. The MASA provides a trusted
trusted repository for audit information concerning privacy repository for audit log information concerning privacy protected
protected bootstrapping events. The MASA is recommended to bootstrapping events.
provide ownership validation services which allows for fully
secure zero-touch bootstrap of domain certificates with mutual
authentication.
We assume a multi-vendor network. In such an environment, there Ownership Tracker An Ownership Tracker service on the global
could a MASA for each vendor that supports devices following this internet. The Ownership Tracker uses business processes to
document's specification, or an integrator could provide a MASA accurately track ownership of all devices shipped against domains
service for all devices. that have purchased them. Although optional this component allows
vendors to provide additional value in cases where their sales and
distribution channels allow for accurately tracking of such
ownership.
We assume a multi-vendor network. In such an environment there could
be a MASA or Ownership Tracker for each vendor that supports devices
following this document's specification, or an integrator could
provide a MASA service for all devices. It is unlikely that an
integrator could provide Ownership Tracking services for multiple
vendors.
This document describes a secure zero-touch approach to bootstrapping This document describes a secure zero-touch approach to bootstrapping
a key infrastructure; if certain devices in a network do not support a key infrastructure; if certain devices in a network do not support
this approach, they can still be bootstrapped manually. Although this approach, they can still be bootstrapped manually. Although
manual deployment is not scalable and is not a focus of this document manual deployment is not scalable and is not a focus of this document
the necessary mechanisms are called out in this document to ensure the necessary mechanisms are called out in this document to ensure
all such edge conditions are covered by the architectural and such edge conditions are covered by the architectural and protocol
protocol models. models.
3. Functional Overview 3. Functional Overview
Entities behave in an autonomic fashion. They discover each other Entities behave in an autonomic fashion. They discover each other
and autonomically bootstrap into a key infrastructure deliminating and autonomically bootstrap into a key infrastructure deliminating
the autonomic domain. See the autonomic domain. See
[I-D.irtf-nmrg-autonomic-network-definitions] for more information. [I-D.irtf-nmrg-autonomic-network-definitions] for more information.
This section details the state machine and operational flow for each This section details the state machine and operational flow for each
of the main three entities. The New Entity, the Domain (primarily of the main three entities. The New Entity, the Domain (primarily
the Registrar) and the MASA service. the Registrar) and the MASA service.
The overall flow is shown in Figure 2: The overall flow is shown in Figure 2:
+---------+ +----------+ +-----------+ +---------+ +----------+ +-----------+
| New | | | | MASA | | New | Proxy | | | Vendor |
| Entity | | Domain | | Service | | Entity | not | Domain | | Service |
| | | | | (Internet)| | | shown | | | (Internet)|
+---------+ +----------+ +-----------+ +---------+ +----------+ +-----------+
| | | | | |
|<-------discovery--------->| | |<-------discovery--------->| |
|---802.1AR credential----->| | |---IEEE 802.1AR identity-->| |
| | | | | |
| [ accept device? ] | | [accept device?] |
| | | | | |
| |---802.1AR identity-------->| | |---IEEE 802.1AR identity--->|
| |---Domain ID--------------->| | |---Domain ID--------------->|
| | | | | |
| | [device belongs] | | [optional: does
| | [to domain? ] | | the device belong
| | | | | to the domain?]
| | [update audit log] | | |
| | | | | [update audit log]
| |<---device history log------| | | |
| |<-- authorization token-----| | |<---device audit log--------|
| | | | |<---audit token-------------|
| [ still accept device?] | | |<-- ownership voucher-------|
| | | | | (optional) |
|<----authorization token---| | | | |
|<----domain information----| | | [ still accept device?] |
| | | | | |
[auth token valid?] | | |<----audit token-----------| |
| | | |<----ownership voucher-----| (optional) |
|----domain enrolment------>| | |<----config information----| |
|<----domain certificate----| | | | |
| | | [audit token valid?] | |
[or ownership voucher valid?] | |
[apply config information] | |
| | |
|----domain enrollment----->| |
|<----domain certificate----| |
| | |
Figure 2 Figure 2
3.1. Behavior of a new entity 3.1. Behavior of a new entity
A New Entity that has not yet been bootstrapped attempts to find a A New Entity that has not yet been bootstrapped attempts to find a
local domain and join it. local domain and join it.
States of a New Entity are as follows: States of a New Entity are as follows:
skipping to change at page 8, line 21 skipping to change at page 9, line 28
| Discover | | Discover |
+------------> | +------------> |
| +------+-------+ | +------+-------+
| | | |
| +------v-------+ | +------v-------+
| | Identity | | | Identity |
^------------+ | ^------------+ |
| rejected +------+-------+ | rejected +------+-------+
| | | |
| +------v-------+ | +------v-------+
| | Request |
| | Join |
| +------+-------+
| |
| +------v-------+
| | Imprint | Optional | | Imprint | Optional
^------------+ <--+Manual input ^------------+ <--+Manual input
| Bad MASA +------+-------+ | Bad Vendor +------+-------+
| response | | response |
| +------v-------+ | +------v-------+
| | Enroll | | | Enroll |
^------------+ | ^------------+ |
| Enroll +------+-------+ | Enroll +------+-------+
| Failure | | Failure |
| +------v-------+ | +------v-------+
| | Being | | | Being |
^------------+ Managed | ^------------+ Managed |
Factory +--------------+ Factory +--------------+
skipping to change at page 9, line 7 skipping to change at page 10, line 17
A. Search for a Proxy on the local link using a link local A. Search for a Proxy on the local link using a link local
discovery protocol (no routable addresses are required for discovery protocol (no routable addresses are required for
this approach). If multiple local proxies are discovered this approach). If multiple local proxies are discovered
attempt communications with each before widening the search attempt communications with each before widening the search
to other options. The proxy relays information to the to other options. The proxy relays information to the
registrar. If this fails: registrar. If this fails:
B. Obtain an IP address using existing methods, such as SLAAC or B. Obtain an IP address using existing methods, such as SLAAC or
DHCPv6, and search for a local registrar using DNS service DHCPv6, and search for a local registrar using DNS service
discovery. If this fails: discovery. [[EDNOTE: ]]If this fails:
C. Obtain an IP address (as above), and search for the domain C. Obtain an IP address (as above), and search for the domain
registrar using a pre-defined Factory provided Internet based registrar using a pre-defined Factory provided Internet based
re-direct service. Various methods could be used, such as re-direct service. Various methods could be used, such as
DNS or RESTful APIs. DNS or RESTful APIs.
2. Identify itself. This is done by presenting an IEEE 802.1AR 2. Identify itself. This is done by presenting an IEEE 802.1AR
credentials to the discovered Registrar (via a Proxy if credentials to the discovered Registrar (via a Proxy if
necessary). Included is a generated nonce that is specific to necessary). Included is a generated nonce that is specific to
this attempt. this attempt.
3. Imprint on the Registrar. This requires verification of the MASA 3. Requests to Join the Discovered domain. The device indicates the
service generated authorization token as provided by the Imprint methods it will accept and provides a nonce ensuring that
contacted Registrar. The authorization token contains the valid any responses can be associated with this particular
domain(s) for this device and is signed by the MASA service. The bootstrapping attempt.
device uses a pre-installed certificate of the MASA service to
validate the signature of the MASA. The nonce information
previously provided is also checked, if it was not removed by the
Registrar.
4. Enroll by accepting the domain specific information from the 4. Imprint on the Registrar. This requires verification of the MASA
registrar, and by enrolling a domain certificate from the service generated Audit Token as provided by the contacted
registrar using a standard enrollment protocol, e.g. Enrolment Registrar or the validation of the vendor provided ownership
voucher. The Audit Token contains the DomainID information for
this device and is signed by the MASA service. The device uses a
pre-installed root certificate of the MASA service to validate
the signature of the Audit Token or the Ownership Voucher.
5. Enroll by accepting the domain specific information from the
Registrar, and by obtaining a domain certificate from the
Registrar using a standard enrollment protocol, e.g. Enrolment
over Secure Transport (EST) [RFC7030]. over Secure Transport (EST) [RFC7030].
5. The New Entity is now a member of and Being Managed by the domain 6. The New Entity is now a member of, and can be managed by, the
and will only repeat the discovery aspects of bootstrapping if it domain and will only repeat the discovery aspects of
is returned to factory default settings. bootstrapping if it is returned to factory default settings.
The following sections describe each of these steps in more detail. The following sections describe each of these steps in more detail.
3.1.1. Discovery and Identity 3.1.1. Discovery
Existing architectures provide the functionality for discovery of the Existing protocols provide the functionality for discovery of the
Domain Registrar. Use of an existing architecture is preferred over Domain Bootstrap Server. The result of discovery might be
development of a new architecture. Discovering of a Domain Proxy communication with a proxy instead of a Domain Bootstrap Server. In
that facilitates communication through to the Domain Registrar is such a case the proxy facilitates communication with the actual
simplified as "discovery of the domain". A proxy is included in Domain Bootstrap Server in a manner that is transparent to the New
Figure 1 although the simplified flow in Figure 2 does not include a Entity.
proxy - under the assuption that the proxy forwarding is mostly
transparent to the New Entity. Existing architectures for
investigation include:
IEEE 802.1X Where the New Entity can be cast as the "supplicant" and To discover the Domain Bootstrap Server the New Entity performs the
the Proxy is the "authenticator". The bootstrapping protocol following actions in this order:
messages are encapsulated as EAP methods. The "authenticator"
reencapsulates the EAPOL frames and forwards them to the
"Authentication Server", which provides Registrar functionalities.
PANA [RFC5191] [[EDNOTE: TBD]] 1. MUST: Obtains a local address using either IPv4 or IPv6 methods
as described in [[EDNOTE: do we need a reference?]].
ND [RFC2461] / [RFC4861] [[EDNOTE: TBD]] NOTE: Neighbor Discovery 2. MUST: Attempt to establish a TLS connection to the next hop
protocols do not describe a mechanism for forwarding messages. neighbor at a well known AN port building on the [[EDNOTE: AN
node discovery discussion, need a reference??]]. [Toerless to
provide updated text]
Each provides a method for the New Entity to discover and initiate 3. MUST: unsecured-GRASP as a link local discovery method?
communication with a local neighbor which is assumed to be a member [Toerless to provide updated text]
of the domain infrastructure. In each protocol methods are available
to support encapsulation of the bootstrapping protocol messages
described elsewhere in this document. Other protocols for
transporting bootstrapping messages can be added in future
references.
All security assocaitions established are between the new device and 4. MAY: Performs DNS-based Service Discovery [RFC6763] over
the Registrar regardless of proxy operations. [[EDNOTE: this is the Multicast DNS [RFC6762] searching for the service
simplest and most direct threat model but should be evaluated against "_bootstrapks._tcp.local."
the anima use cases. It may be preferable to engage in secure
communications with the proxy itself?]]
The New Entity is expected to identify itself during one of the 5. MAY: Performs DNS-based Service Discovery [RFC6763] over normal
communication protocol exchanges. For example using EAP-TLS. If the DNS operations. In this case the domain is known so the service
client identity is rejected the New Entity repeats the Discovery searched for is "_bootstrapks._tcp.example.com".
process using the next proxy or discovery method available. If
multiple proxies are available the New Entity tries each until a
successful bootstrapping occurs. The New Entity may prioritize
proxies selection order as appropriate for the anticipated
environment.
If Proxy discovery fails the New Entity moves on to discovering a 6. MAY: If no local bootstrapks service is located using the DNS-
Registrar directly using an appropriate L3 protocol mechanisms. based Sevice Discovery methods the New Entity contacts a well
known vendor provided bootstrapping server by perfoming a DNS
lookup using a well known URI such as "bootstrapks.vendor-
example.com".
Once a domain bootstrapping server is discovered the New Entity
communicates with the discovered server using the bootstrapping
protocol defined in Section 5. The current DNS services returned
during each query is maintained until bootstrapping is completed. If
bootstrapping fails and the New Entity returns to the Discovery state
it picks up where it left off and continues attempting bootstrapping.
For example if the first Multicast DNS _bootstrapks._tcp.local
response doens't work then the second and third responses are tried.
If these fail the New Entity moves on to normal DNS-based Service
Discovery.
Once all discovered services are attempted the device SHOULD return
to Multicast DNS and keep trying. The New Entity may prioritize
selection order as appropriate for the anticipated environment.
[[EDNOTE: An appropriate backoff or rate limiting strategy should be
defined here such that the device doesn't flood the local network
with queries. If the device were to eventually give up -- or at
least have too long between attempts -- a power cycle would restart
the backoff mechanism.]]
[[EDNOTE: it is unclear yet if discovery happens on a per interface [[EDNOTE: it is unclear yet if discovery happens on a per interface
basis or once per device. What is the requirement around joining basis or once per device. What is the requirement around joining
multiple domains; is this a bootstrapping requirement or is this a multiple domains; is this a bootstrapping requirement or is this a
broader autonomic requirement]] broader autonomic requirement]] [[EDNOTE: b. carpenter: I seem to
think we settled on joining one domain (which might be a sub-domain)
and then doing some sort of cross-certification to get authenticated
and authorized in another domain. If so, it isn't a bootstrap
requirement.]]
3.1.2. Imprint 3.1.2. Identity
The New Entity identifies itself during the communication protocol
handshake. If the client identity is rejected the New Entity repeats
the Discovery process using the next proxy or discovery method
available.
The boostrapping protocol server is as of yet not validated. Thus
this connection is provisional and all data recieved is untrusted
until sufficiently validated even though it is over a (D)TLS
connection. This is aligned with the existing provisional mode of
EST [RFC7030] during s4.1.1 "Bootstrap Distribution of CA
Certificates".
All security associations established are between the new device and
the Bootstrapping server regardless of proxy operations.
3.1.3. Request Join
The New Entity POSTs a request to join the domain to the
Bootstrapping server. This request contains a New Entity generated
nonce and informs the Bootstrapping server which imprint methods the
New Entity will accept.
As indicated in EST [RFC7030] the bootstrapping server MAY redirect
the client to an alternate server. This is most useful in the case
where the New Entity has resorted to a well known vendor URI and is
communicating with the vendor's Registrar directly. In this case the
New Entity has authenticated the Registrar using the local Implicit
Trust Anchor database and can therefore treat the redirect URI as a
trusted URI which can also be validated using the Implicit Trust
Anchor database. Since client authentication occurs during the TLS
handshake the bootstrapping server has sufficient information to
apply appropriate policy concerning which server to redirect to.
The nonce ensures the New Entity can verify that responses are
specific to this bootstrapping attempt. This minimizes the use of
global time and provides a substantial benefit for devices without a
valid clock.
3.1.4. Imprint
The domain trust anchor is received by the New Entity during the The domain trust anchor is received by the New Entity during the
boostrapping protocol methods in the form of a MASA authorization boostrapping protocol methods in the form of either an Audit Token
token containing the domainID. The goal of the imprint state is to containing the domainID or an explicit ownership voucher. The goal
securely obtain a copy of this trust anchor without involving human of the imprint state is to securely obtain a copy of this trust
interaction. anchor without involving human interaction.
An enrollment protocol such as EST [RFC7030] details a set of non- The enrollment protocol EST [RFC7030] details a set of non-autonomic
autonomic bootstrapping methods such as: bootstrapping methods such as:
o using the Implicit Trust Anchor database (not an autonomic o using the Implicit Trust Anchor database (not an autonomic
solution because the URL must be securely distributed), solution because the URL must be securely distributed),
o engaging a human user to authorize the CA certificate using out- o engaging a human user to authorize the CA certificate using out-
of-band data (not an autonomic solution because the human user is of-band data (not an autonomic solution because the human user is
involved), involved),
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).
This document describes an additional autonomic method: This document describes additional autonomic methods:
MASA authorization token Authorization tokens are obtained by the MASA audit token Audit tokens are obtained by the Registrar from the
Registrar from the MASA service and presented to the New Entity MASA service and presented to the New Entity for validation.
for validation. These indicate to the New Entity that joining the domain has been
logged by a trusted logging server.
Ownership Voucher Ownership Vouchers are obtained by the Registrar
from the MASA service and explicitly indicate the fully qualified
domain name of the domain the new entity currently belongs to.
Since client authentication occurs during the TLS handshake the
bootstrapping server has sufficient information to apply appropriate
policy concerning which method to use.
An arbitrary basic configuration information package that is signed An arbitrary basic configuration information package that is signed
by the domain can be delivered alongside the authorization token. by the domain can be delivered alongside the Audit Token or ownership
This information is signed by the domain private keys and is a one validation. This information is signed by the domain private keys
time delivery containing information such as which enrollment server and is a one time delivery containing information such as which
to communicate with and which management system to communicate with. enrollment server to communicate with and which management system to
It is intended as a limited basic configuration for these purposes communicate with. It is intended as a limited basic configuration
and is not intended to deliver entire final configuration to the for these purposes and is not intended to deliver entire final
device. configuration to the device.
If the autonomic methods fails the New Entity returns to discovery If the autonomic methods fail the New Entity returns to discovery
state and attempts bootstrapping with the next available discovered state and attempts bootstrapping with the next available discovered
Registrar. Registrar.
3.1.3. Enrollment 3.1.5. Enrollment
As the final step of bootstrapping a Registrar helps to issue a As the final step of bootstrapping a Registrar helps to issue a
domain specific credential to the New Entity. For simplicity in this domain specific credential to the New Entity. For simplicity in this
document, a Registrar primarily facilitates issuing a credential by document, a Registrar primarily facilitates issuing a credential by
acting as an RFC5280 Registration Authority for the Domain acting as an RFC5280 Registration Authority for the Domain
Certification Authority. Certification Authority.
Enrollment proceeds as described in Enrollment over Secure Transport Enrollment proceeds as described in Enrollment over Secure Transport
(EST) [RFC7030]. The New Entity contacts the Registrar using EST as (EST) [RFC7030]. The New Entity contacts the Registrar using EST as
indicated: indicated:
o The New Entity is authenticated using the IEEE 802.1AR o The New Entity is authenticated using the IEEE 802.1AR
credentials. credentials.
o The EST section 4.1.3 CA Certificates Response is verified using o The EST section 4.1.3 CA Certificates Response is verified using
the MASA authorization token provided domain identity. either the Audit Token which provided the domain identity -or-
3.1.4. Being Managed o The EST server is authenticated by using the Owership Voucher
indicated fully qualified domain name to build the EST URI such
that EST section 4.1.1 bootstrapping using the New Entity implicit
Trust Anchor database can be used.
3.1.6. Being Managed
Functionality to provide generic "configuration" information is Functionality to provide generic "configuration" information is
supported. The parsing of this data and any subsequent use of the supported. The parsing of this data and any subsequent use of the
data, for example communications with a Network Management System is data, for example communications with a Network Management System is
out of scope but is expected to occur after bootstrapping enrollment out of scope but is expected to occur after bootstrapping enrollment
is complete. This ensures that all communications with management is complete. This ensures that all communications with management
systems which can divulge local security information (e.g. network systems which can divulge local security information (e.g. network
topology or raw key material) is secured using the local credentials topology or raw key material) is secured using the local credentials
issued during enrollment. issued during enrollment.
See Section 3.5. See Section 3.5.
3.2. Behavior of a proxy 3.2. Behavior of a proxy
The role of the Proxy is to facilitate communications. The Proxy The role of the Proxy is to facilitate communications. The Proxy
forwards messages between the New Entity and a Registrar. Where forwards EST transport (TLS or DTLS) packets between the New Entity
existing protocols, as detailed in Section 3.1.1, already provide and the Registrar that has been configured on the Proxy.
this functionality nothing additional is defined.
3.3. Behavior of the Registrar [[EDNOTE: To what extent do we need to explain how this occurs? It
is sufficient to indicate the basic behavior or do we need to
indicate here all the details? A rough implementation of an ipv4
proxy would be as follows:
Once a registrar is established it listens for new entities and socat -v tcp4-listen:443,reuseaddr,fork tcp4:registrar.example.com:443
There have been suggestions that a stateless proxy implementation
using a DTLS extension would be preferred. Is this a future
optimization opportunity or a short term requirement?]]
3.3. Behavior of the Registrar (Bootstrap Server)
Once a Registrar is established it listens for new entities and
determines if they can join the domain. The registrar delivers any determines if they can join the domain. The registrar delivers any
necessary authorization information to the new device and facilitates necessary authorization information to the new device and facilitates
enrollment with the domain PKI. enrollment with the domain PKI.
Registrar behavior is as follows: Registrar behavior is as follows:
Contacted by New Entity Contacted by New Entity
+ +
| |
+-------v----------+ +-------v----------+
skipping to change at page 13, line 30 skipping to change at page 16, line 30
| Entity +---------> | Entity +--------->
+-------+----------+ | +-------+----------+ |
| | | |
+-------v----------+ | +-------v----------+ |
| Log Verification | fail? | | Log Verification | fail? |
| +---------> | +--------->
+-------+----------+ | +-------+----------+ |
| | | |
+-------v----------+ +----v-------+ +-------v----------+ +----v-------+
| Forward | | | | Forward | | |
| Authorization | | Reject | | Audit | | Reject |
| token + config | | Device | | token + config | | Device |
| to the Entity | | | | to the Entity | | |
+------------------+ +------------+ +------------------+ +------------+
Figure 4 Figure 4
3.3.1. Entity Authentication 3.3.1. Entity Authentication
The applicable authentication methods detailed in EST [RFC7030] are: The applicable authentication methods detailed in EST [RFC7030] are:
o the use of an IEEE 802.1AR IDevID credential, o the use of an IEEE 802.1AR IDevID credential,
o or the use of a secret that is transmitted out of band between the o or the use of a secret that is transmitted out of band between the
New Entity and the Registrar (this use case is not autonomic). New Entity and the Registrar (this use case is not autonomic).
3.3.2. Entity Authorization 3.3.2. Entity Authorization
In a fully automated network all devices must be securely identified. In a fully automated network all devices must be securely identified
and authorized to join the domain.
A Registrar accepts or declines a request to join the domain, based A Registrar accepts or declines a request to join the domain, based
on the authenticated identity presented and other policy defined on the authenticated identity presented. Automated acceptance
criteria such as Proxy identity. Automated acceptance criteria criteria include:
include:
o allow any device of a specific type (as determined by the IEEE o allow any device of a specific type (as determined by the IEEE
802.1AR device identity), 802.1AR device identity),
o allow any device from a specific Factory (as determined by the o allow any device from a specific vendor (as determined by the IEEE
IEEE 802.1AR identity), 802.1AR identity),
o allow a specific device from a Factory (as determined by the IEEE o allow a specific device from a vendor (as determined by the IEEE
802.1AR identity) 802.1AR identity)
In all cases a Registrar must use the globally available MASA service Since all New Entities accept Audit Tokens the Registrar MUST use the
to verify that the device's history log does not include unexpected vendor provided MASA service to verify that the device's history log
Registrars. Because if a device had previously registered with does not include unexpected Registrars. If a device had previously
another domain, the registrar of that domain would show in the log. registered with another domain, the Registrar of that domain would
show in the log.
If a device is accepted into the domain, it is then invited to In order to validate the IEEE 802.1AR device identity the Registrar
request a domain certificate through a certificate enrolment process. maintains a database of vendor trust anchors (e.g. vendor root
The result is a common trust anchor and device certificates for all certificates or keyIdentifiers for vendor root public keys). For
autonomic devices in a domain. These certificates can subsequently user interface purposes this database can be mapped to colloquial
be used to determine the boundaries of the homenet, to authenticate vendor names. Registrars can be shipped with the trust anchors of a
other domain nodes, and to autonomically enable services on the significant number of third-party vendors within the target market.
homenet.
For each entity that will be accepted a Registrar maintains the If a device is accepted into the domain, it is expected request a
Factory CA identity and the entity's unique identifier. The Factory domain certificate through a certificate enrolment process. The
CA identity could be implemented as the Factory CA root certificate result is a common trust anchor and device certificates for all
keyIdentifier (the 160-bit SHA-1 hash of the value of the BIT STRING autonomic devices in a domain (these certificates can subsequently be
subjectPublicKey). For user interface purposes the keyIdentifier used to determine the boundaries of the homenet, to authenticate
information can be mapped to a colloquial Factory name (Registrars other domain nodes, and to autonomically enable services on the
can be shipped with the keyIdentifier of a significant number of homenet). The authorization performed during this phase MAY be
third-party manufacturers). cached for the TLS session and applied to subsequent EST enrollment
requests so long as the session lasts.
3.3.3. Claiming the New Entity 3.3.3. Claiming the New Entity
During initial bootstrapping the New Entity provides a nonce specific
to the particular bootstrapping attempt. The registrar should
include this nonce when claiming the New Entity from the Internet
based MASA service. If a nonce is provided by the Registrar, then
claims from an unauthenticated Registrar are serviced by the MASA
resource.
The Registrar can claim a New Entity that is not online by forming
the request using the entities unique identifier but not including a
nonce in the claim request. MASA authorization tokens obtained in
this way do not have a lifetime and they provide a permanent method
for the domain to claim the device. Evidence of such a claim is
provided in the audit log entries available to any future Registrar.
Such claims reduce the ability for future domains to secure
bootstrapping and therefore the Registrar MUST be authenticated by
the MASA service.
Claiming an entity establishes an audit log at the MASA server and Claiming an entity establishes an audit log at the MASA server and
provides the Registrar with proof, in the form of a MASA provides the Registrar with proof, in the form of a MASA
authorization token, that the log entry has been inserted. As authorization token, that the log entry has been inserted. As
indicated in Section 3.1.2 a New Entity will only proceed with indicated in Section 3.1.4 a New Entity will only proceed with
bootstrapping if a validated MASA authorization token has been bootstrapping if a validated MASA authorization token has been
recieved. The New Entity therefore enforces that bootstrapping only recieved. The New Entity therefore enforces that bootstrapping only
occurs if the claim has been logged. occurs if the claim has been logged.
Registrar's obtain the MASA URI via static configuration or by
extracting it from the IEEE 802.1AR credentail. [[EDNOTE: An
appropriate extension for indicating the MASA URI could be defined in
this document]].
If ownership validation methods are being used the 'claiming' occured
during out-of-band integration within the sales process and is out-
of-scope. Instead the Registar simply requests an ownership
validation token.
During initial bootstrapping the New Entity provides a nonce specific
to the particular bootstrapping attempt. The Registrar SHOULD
include this nonce when claiming the New Entity from the MASA
service. Claims from an unauthenticated Registrar are only serviced
by the MASA resource if a nonce is provided.
The Registrar can claim a New Entity that is not online by forming
the request using the entities unique identifier and not including a
nonce in the claim request. Audit Tokens obtained in this way do not
have a lifetime and they provide a permanent method for the domain to
claim the device. Evidence of such a claim is provided in the audit
log entries available to any future Registrar. Such claims reduce
the ability for future domains to secure bootstrapping and therefore
the Registrar MUST be authenticated by the MASA service. [[EDNOTE:
some of this paragraph content belongs in the section on MASA
behavior]]
3.3.4. Log Verification 3.3.4. Log Verification
The Registrar requests the log information for the new entity from The Registrar requests the log information for the new entity from
the MASA service. The log is verified to confirm that the following the MASA service. The log is verified to confirm that the following
is true to the satisfaction of the registrar's configured parameters: is true to the satisfaction of the Registrar's configured policy:
o Any nonceless entries in the log are associated with domainIDs o Any nonceless entries in the log are associated with domainIDs
recognized by the registrar. The registar MAY be configured to recognized by the registrar.
ignore the history of the device but it is RECOMMENDED that this
only be configured if the MASA server is known to perform
ownership validation or if Trusted Computing Group secure boot and
remote attestation is available.
o Any nonce'd entries are older than when the domain is known to o Any nonce'd entries are older than when the domain is known to
have physical possession of the new entity or that the domainIDs have physical possession of the new entity or that the domainIDs
are recognized by the registrar. are recognized by the registrar.
If any of these criteria are unacceptable to the registrar the entity If any of these criteria are unacceptable to the registrar the entity
is rejected. is rejected. The registar 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.
3.3.5. Forwarding Authorization Token plus Configuration 3.3.5. Forwarding Audit Token plus Configuration
The Registrar forwards the received authorization token to the new The Registrar forwards the received Audit Token to the New Entity.
entity. To simplify the message flows an initial configuration To simplify the message flows an initial configuration package can be
package can be delivered at this time which is signed by a delivered at this time which is signed by a representative of the
representative of the domain. domain.
[[EDNOTE: format TBD. The configuration package signature data must [[EDNOTE: format TBD. The configuration package signature data must
contain the full certificate path sufficient for the new entity to contain the full certificate path sufficient for the new entity to
use the domainID information (as a trust anchor) to accept and use the domainID information (as a trust anchor) to accept and
validate the configuration)]] validate the configuration)]]
3.4. Behavior of the MASA Service 3.4. Behavior of the MASA Service
The MASA service is provided by the Factory provider on the global The MASA service is provided by the Factory provider on the global
Internet. The URI of this service is well known. The URI should be Internet. The URI of this service is well known. The URI SHOULD
provided as an IEEE 802.1AR IDevID X.509 extension (a "MASA also be provided as an IEEE 802.1AR IDevID X.509 extension (a "MASA
authorization token Distribution Point" extension). Audit Token Distribution Point" extension).
The MASA service provides the following functionalities to The MASA service provides the following functionalities to
Registrars: Registrars:
3.4.1. Issue Authorization Token and Log the event 3.4.1. Issue Authorization Token and Log the event
A Registrar POSTs a claim message optionally containing the bootstrap A Registrar POSTs a claim message optionally containing the bootstrap
nonce to the MASA server. nonce to the MASA server.
If a nonce is provided the MASA service responds to all requests. If a nonce is provided the MASA service responds to all requests.
The MASA service verifies the Registrar is representative of the The MASA service verifies the Registrar is representative of the
domain and generates a privacy protected log entry before responding domain and generates a privacy protected log entry before responding
with the authorization token. with the Audit Token.
If a nonce is not provided then the MASA service MUST authenticate If a nonce is not provided then the MASA service MUST authenticate
the Registrar as a valid customer. This prevents denial of service the Registrar as a valid customer. This prevents denial of service
attacks. The specific level of authentication provided by the attacks. The specific level of authentication provided by the
customer is not defined here. An MASA Practice Statement (MPS) customer is not defined here. An MASA Practice Statement (MPS)
similar to the Certification Authority CPS, as defined in RFC5280, is similar to the Certification Authority CPS, as defined in RFC5280, is
provided by the Factory such that Registrar's can determine the level provided by the Factory such that Registrar's can determine the level
of trust they have in the Factory. of trust they have in the Factory.
3.4.2. Retrieve Audit Entries from Log 3.4.2. Retrieve Audit Entries from Log
skipping to change at page 17, line 16 skipping to change at page 20, line 28
3.5.1. Network boundaries 3.5.1. Network boundaries
When a device has joined the domain, it can validate the domain When a device has joined the domain, it can validate the domain
membership of other devices. This makes it possible to create trust membership of other devices. This makes it possible to create trust
boundaries where domain members have higher level of trusted than boundaries where domain members have higher level of trusted than
external devices. Using the autonomic User Interface, specific external devices. Using the autonomic User Interface, specific
devices can be grouped into to sub domains and specific trust levels devices can be grouped into to sub domains and specific trust levels
can be implemented between those. can be implemented between those.
3.6. Interactions with Network Access Control
The assumption is that Network Access Control (NAC) completes using
the New Entity 802.1AR credentials and results in the device having
sufficient connetivity to discovery and communicate with the proxy.
Any additional connectivity or quarantine behavior by the NAC
infrastructure is out-of-scope. After the devices has completed
bootstrapping the mechanism to trigger NAC to re-authenticate the
device and provide updated network privileges is also out-of-scope.
This achieves the goal of a bootstrap architecture that can integrate
with NAC but does not require NAC within the network where it wasn't
previously required. Future optimizations can be achieved by
integrating the bootstrapping protocol directly into an initial EAP
exchange.
4. Domain Operator Activities 4. Domain Operator Activities
This section describes how an operator interacts with a domain that This section describes how an operator interacts with a domain that
supports the bootstrapping as described in this document. supports the bootstrapping as described in this document.
4.1. Instantiating the Domain Certification Authority 4.1. Instantiating the Domain Certification Authority
This is a one time step by the domain administrator. This is an "off This is a one time step by the domain administrator. This is an "off
the shelf" CA with the exception that it is designed to work as an the shelf" CA with the exception that it is designed to work as an
integrated part of the security solution. This precludes the use of integrated part of the security solution. This precludes the use of
skipping to change at page 18, line 42 skipping to change at page 22, line 26
Internet connectivity. Even when the Internet based MASA service is Internet connectivity. Even when the Internet based MASA service is
used, it is possible to pre-fetch the required information from the used, it is possible to pre-fetch the required information from the
MASA a priori, for example at time of purchase such that devices can MASA a priori, for example at time of purchase such that devices can
enrol later. This supports use cases where the domain network may be enrol later. This supports use cases where the domain network may be
entirely isolated during device deployment. entirely isolated during device deployment.
Additional policy can be stored for future authorization decisions. Additional policy can be stored for future authorization decisions.
For example an expected deployment time window or that a certain For example an expected deployment time window or that a certain
Proxy must be used. Proxy must be used.
4.4. Automatic Enrolment of Devices 4.4. Automatic Enrollment of Devices
The approach outlined in this document provides a secure zero-touch The approach outlined in this document provides a secure zero-touch
method to enrol new devices without any pre-staged configuration. method to enrol new devices without any pre-staged configuration.
New devices communicate with already enrolled devices of the domain, New devices communicate with already enrolled devices of the domain,
which proxy between the new device and a Registrar. As a result of which proxy between the new device and a Registrar. As a result of
this completely automatic operation, all devices obtain a domain this completely automatic operation, all devices obtain a domain
based certificate. based certificate.
4.5. Secure Network Operations 4.5. Secure Network Operations
skipping to change at page 19, line 47 skipping to change at page 23, line 34
The "New Entity" is the EST client and the "Registrar" is the EST The "New Entity" is the EST client and the "Registrar" is the EST
server. server.
The extensions for the client are as follows: The extensions for the client are as follows:
o The New Entity provisionally accept the EST server certificate o The New Entity provisionally accept the EST server certificate
during the TLS handshake as detailed in EST section 4.1.1 during the TLS handshake as detailed in EST section 4.1.1
("Bootstrap Distribution of CA Certificates"). ("Bootstrap Distribution of CA Certificates").
o The New Entity request and validates a "bootstrap token" as o The Registrar requests and validates the Audit Token from the
described below. At this point the New Entity has sufficient vendor authorized MASA service.
information to validate domain credentials.
o The New Entity requests and validates the Audit Token as described
below. At this point the New Entity has sufficient information to
validate domain credentials.
o The New Entity calls the EST defined /cacerts method to obtain the o The New Entity calls the EST defined /cacerts method to obtain the
current CA certificate. These are validated using the "bootstrap current CA certificate. These are validated using the Audit
token". Token.
o The New Entity completes bootstrapping as detailed in EST section o The New Entity completes bootstrapping as detailed in EST section
4.1.1. 4.1.1.
These extensions could be implemented as an independent protocol from These extensions could be implemented as an independent protocol from
EST but since the overlap with basic enrollment is extensive, EST but since the overlap with basic enrollment is extensive,
particularly with respect to client authorization, they are presented particularly with respect to client authorization, they are presented
here as additions to EST. here as additions to EST.
In order to obtain a validated bootstrap token and history logs the In order to obtain a validated Audit Token and Audit Log the
Registrar contacts the MASA service Service using REST calls. Registrar contacts the MASA service Service using REST calls:
5.1. EAP-EST +-----------+ +----------+ +-----------+ +----------+
| New | | | | | | |
| Entity | | Proxy | | Registrar | | Vendor |
| | | | | | | |
++----------+ +--+-------+ +-----+-----+ +--------+-+
| | | |
| | | |
| (D)TLS hello | | |
Establish +---------------> (D)TLS hello | |
(D)TLS | |---------------> |
connection | (forwarding) | |
| Server Cert <---------------+ |
<---------------+ | |
| Client Cert | | |
+-------------------------------> |
| | | |
HTTP REST | POST /requestaudittoken | |
Data +--------------------nonce------> |
| . | /requestaudittoken
| . +---------------->
| <----------------+
| | /requestauditlog
| +---------------->
| audit token or owner voucher <----------------+
<-------------------------------+ |
| (optional config information) | |
| . | |
| . | |
In order to support Proxy environments EAP-EST is defined. Figure 5
[[EDNOTE: TBD. EST is TLS with some data. EAP-TLS and other similar In some use cases the Registrar may need to contact the Vendor in
protocols provide an example framework for filling out this section]] advanced, for example when the target network is airgapped. The
nonceless request format is provided for this and the resulting flow
is slightly different. The security differences associated with not
knowning the nonce are discussed below:
5.2. Request bootstrap token +-----------+ +----------+ +-----------+ +----------+
| New | | | | | | |
| Entity | | Proxy | | Registrar | | Vendor |
| | | | | | | |
++----------+ +--+-------+ +-----+-----+ +--------+-+
| | | |
| | | |
| | | /requestaudittoken
| | (nonce +---------------->
| | unknown) <----------------+
| | | /requestauditlog
| | +---------------->
| | <----------------+
| (D)TLS hello | | |
Establish +---------------> (D)TLS hello | |
(D)TLS | |---------------> |
connection | (forwarding) | |
| SerVer Cert <---------------+ |
<---------------+ | |
| Client Cert | | |
+-------------------------------> |
| | | |
HTTP REST | POST /requestaudittoken | |
Data +----------------------nonce----> (discard |
| audit token or owner Voucher | nonce) |
<-------------------------------+ |
| (optional config information) | |
| . | |
| . | |
Figure 6
5.1. Request Audit Token
When the New Entity reaches the EST section 4.1.1 "Bootstrap When the New Entity reaches the EST section 4.1.1 "Bootstrap
Distribution of CA Certificates" [[EDNOTE: out of date xref]] state Distribution of CA Certificates" state but wishes to proceed in a
but wishes to proceed in a fully automated fashion it makes a request fully automated fashion it makes a request for a MASA authorization
for a MASA authorization token from the Registrar. token from the 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
"/requestbootstraptoken". "/requestaudittoken".
The request format is JSON object containing a nonce. The request format is JSON object containing a nonce.
Request media type: application/masanonce Request media type: application/auditnonce
Request format: a json file with the following: Request format: a JSON file with the following:
{"nonce":"<64bit nonce value>"} {"nonce":"<64bit nonce value>", "OwnershipValidation":boolean}
[[EDNOTE: exact format TBD. There is an advantage to having the [[EDNOTE: exact format TBD. There is an advantage to having the
client sign the nonce (similar to a PKI Certification Signing client sign the nonce (similar to a PKI Certification Signing
Request) since this allows the MASA service to confirm the actual Request) since this allows the MASA service to confirm the actual
device identity. It is not clear that there is a security benefit device identity. It is not clear that there is a security benefit
from this.]] from this since its the New Entity that verifies the nonce.]]
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. The registrar performs authorization as [RFC7030] section 3.3.2. The registrar performs authorization as
detailed in Section 3.3.2. If authorization is successful the detailed in Section 3.3.2. If authorization is successful the
Registrar obtains a MASA authorization token from the MASA service Registrar obtains an Audit Token from the MASA service (see
(see Section 5.3). Section 5.2).
The recieved MASA authorization token is returned to the New Entity. The recieved MASA authorization token is returned to the New Entity.
5.3. Request MASA authorization token As indicated in EST [RFC7030] the bootstrapping server can redirect
the client to an alternate server. If the New Entity authenticated
the Registrar using the well known URI method then the New Entity
MUST follow the redirect automatically and authenticate the new
Registrar against the redirect URI provided. If the New Entity had
not yet authenticated the Registrar because it was discovered and was
not a known-to-be-valid URI then the new Registrar must be
authenticated using one of the two autonomic methods described in
this document.
A registrar requests the MASA authorization token from the MASA 5.2. Request Audit Token from MASA
service using a REST interface.
The Registrar requests the Audit Token from the MASA service using a
REST interface. For simplicity this is defined as an optional EST
message between the Registar and an EST 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
"/requestMASAauthorization". "/requestaudittoken".
The request format is a JSON object optionally containing the nonce The request format is a JSON object optionally containing the nonce
value (as obtained from the bootstrap request) and the IEEE 802.1AR value (as obtained from the bootstrap request) and the IEEE 802.1AR
identity of the device as a serial number (the full certificate is identity of the device as a serial number (the full certificate is
not needed and no proof-of-possession information for the device not needed and no proof-of-possession information for the device
identity is included). The New Entity's serial number is extracted identity is included). The New Entity's serial number is extracted
from the subject name : from the subject name :
{"nonce":"<64bit nonce value>", "serialnumber", "<subjectname/ {"nonce":"<64bit nonce value>", "serialnumber", "<subjectname/
subjectaltname serial number>"} subjectaltname serial number>"}
Inclusion of the nonce is optional because the Registar might request Inclusion of the nonce is optional because the Registar might request
an authorization token when the New Entity is not online, or when the an authorization token when the New Entity is not online, or when the
target bootstrapping environment is not on the same network as the target bootstrapping environment is not on the same network as the
MASA server. MASA server.
This information is encapsulated in a PKCS7 signed data structure The JSON message information is encapsulated in a PKCS7 signed data
that is signed by the Registrar. The entire certificate chain, up to structure that is signed by the Registrar. The entire certificate
and including the Domain CA, is included in the PKCS7. chain, up to and including the Domain CA, MUST be included in the
PKCS7.
The MASA service checks the internal consistency of the PKCS7 but is The MASA service checks the internal consistency of the PKCS7 but is
unable to actually authenticate the domain identity information. The unable to actually authenticate the domain identity information. The
domain is not know to the MASA server in advance and a shared trust domain is not know to the MASA server in advance and a shared trust
anchor is not implied. The MASA server verifies that the PKCS7 is anchor is not implied. The MASA server verifies that the PKCS7 is
signed by a Registrar (by checking for the cmc-idRA field in the signed by a Registrar (by checking for the cmc-idRA field in the
Registrar certificate) certificate that was issued by the root Registrar certificate) certificate that was issued by a the root
certificate included in the PKCS7. certificate included in the PKCS7. This is sufficient for the MASA
service to ensure that the Registar is in fact an authorized Registar
of the unknown domain.
The domain ID is extracted from the root certificate and is used to The domain ID (e.g. hash of the public key of the domain) is
generate the MASA authorization token and to update the audit log. extracted from the root certificate and is used to generate the MASA
authorization token and to update the audit log.
[[EDNOTE: The authorization token response format needs to be defined [[EDNOTE: The authorization token response format needs to be defined
here. It consists of the nonce, if supplied, the serialnumber and here. It consists of the nonce, if supplied, the serialnumber and
the trust anchor of the domain. For example: the trust anchor of the domain. For example:
{"nonce":"<64bit nonce value>", "serialnumber", "<subjectname/ {"nonce":"<64bit nonce value>", "serialnumber", "<subjectname/
subjectaltname serial number>","domainID":} subjectaltname serial number>","domainID":}
]] ]]
[[EDNOTE: This assumes the Registrar can extract the serial number [[EDNOTE: This assumes the Registrar can extract the serial number
successfullly from the cilent certificate. The RFC4108 successfullly from the cilent certificate. The RFC4108
hardwareModuleName is likely the best known location.]] hardwareModuleName is the best known location.]]
5.4. Basic Configuration Information Package [[EDNOTE: There is a strong similarity between this and the previous
section. Both involve requesting the Audit Token from the upstream
element. Because there are differing requirements on the data
submitted and the signing of that data they are specified in distinct
sections. The design team should have a meeting to discuss how to
unify these sections or make the distinctions more clear]]
5.3. Basic Configuration Information Package
When the MASA authorization token is returned to the New Entity an When the MASA authorization token is returned to the New Entity an
arbitrary information package can be signed and delivered along side arbitrary information package can be signed and delivered along side
it. This is signed by the Domain Registar. The New Entity first it. This is signed by the Domain Registar. The New Entity first
verifies the MASA authorization token and, if it is valid, then uses verifies the Audit Token and, if it is valid, then uses the domain's
the domain's TA to validate the Information Package. TA to validate the Information Package.
[[EDNOTE: The package format to be specified here. Any signed format [[EDNOTE: The package format to be specified here. Any signed format
is viable and ideally one can simply be specified from netconf. The is viable and ideally one can simply be specified from netconf. The
Registar knows the New Entity device type from the 802.1AR credential Registar knows the New Entity device type from the 802.1AR credential
and so is able to determine the proper format for the configuration]] and so is able to determine the proper format for the configuration]]
5.5. Request MASA authorization log 5.4. Request MASA authorization log
A registrar requests the MASA authorization log from the MASA service A registrar requests the MASA authorization log from the MASA service
using this EST extension. using this EST extension.
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
"/requestMASAlog". "/requestMASAlog".
The log data returned is a file consisting of all previous log The log data returned is a file consisting of all previous log
entries. For example: entries. For example:
"log":[ "log":[
{"date":"<date/time of the entry>"}, {"date":"<date/time of the entry>"},
"domainID":"<domainID as extracted from the root "domainID":"<domainID as extracted from the root
certificate within the PKCS7 of the certificate within the PKCS7 of the
authorization token request>", audit token request>",
"nonce":"<any nonce if supplied (or NULL)>"}, "nonce":"<any nonce if supplied (or NULL)>"},
{"date":"<date/time of the entry>"}, {"date":"<date/time of the entry>"},
"domainID":"<domainID as extracted from the root "domainID":"<domainID as extracted from the root
certificate within the PKCS7 of the certificate within the PKCS7 of the
authorization token request>", audit token request>",
"nonce":"<any nonce if supplied (or NULL)>"}, "nonce":"<any nonce if supplied (or NULL)>"},
] ]
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: only the most recent nonce'd log entry is be optimized as follows: only the most recent nonce'd log entry is
required in the response. All nonce-less entries for the same required in the response. All nonce-less entries for the same
domainID can be condensed into the single most recent nonceless domainID can be condensed into the single most recent nonceless
entry. entry.
The Registrar uses this log information to make an informed decision The Registrar uses this log information to make an informed decision
regarding the continued bootstrapping of the New Entity. regarding the continued bootstrapping of the New Entity.
[[EDNOTE: certificate transparency might offer an alternative log [[EDNOTE: certificate transparency might offer an alternative log
skipping to change at page 23, line 28 skipping to change at page 29, line 20
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 New Entity, Registrar and MASA sections detail specific ways that the New Entity, Registrar and MASA
can be configured to run in a less secure mode for the indicated can be configured to run in a less secure mode for the indicated
reasons. reasons.
6.1. New Entity security reductions 6.1. New Entity security reductions
Although New Entity can choose to run in less secure modes this is Although New Entity can choose to run in less secure modes this is
MUST NOT be the default state because it permanently degrades the MUST NOT be the default state because it permanently degrades the
security for all other uses cases. When configured into lower security for all other uses cases.
security modes by a trusted administrator:
1. The device may have an operational mode where it skips The device may have an operational mode where it skips Audit Token
authorization token validation. For example if a physical button validation one time. For example if a physical button is depressed
is depressed during the bootstrapping operation. This may occur during the bootstrapping operation. This can be useful if the MASA
when: A device Factory goes out of business or otherwise fails to service is unavailable. This behavior SHOULD be available via local
provide a reliable MASA service or when local staging has pre- configuration or physical presence methods to ensure new entities can
configured the New Entity with a known good Trust Anchor. always be deployed even when autonomic methods fail.
2. The device may be configured during staging or requested from the It is RECOMMENDED that this only be available if hardware assisted
factory to not require the MASA service authorization token. An NEA [RFC5209] is supported.
entity that does not validate the domain identity is inherently
dangerous as it may have had malware installed on it by a man-in-
the-middle. This risk should be mitigated using attestation and
measurement technologies. In order to support an unsecured
imprint the New Entity MUST support remote attestation
technologies such as is defined by the Trusted Computing Group.
[[EDNOTE: How to include remote attestation into the boostrapping
protocol exchange is TBD]]. This may occur when: The device
Factory does not provide a MASA service.
6.2. Registrar security reductions 6.2. Registrar security reductions
The Registrar can choose to accept devices using less secure methods. The Registrar can choose to accept devices using less secure methods.
These methods are RECOMMENDED when low security models are needed as These methods are RECOMMENDED when low security models are needed as
the security decisions are being made by the local administrator: the security decisions are being made by the local administrator:
1. The registrar may choose to accept all devices, or all devices of 1. The registrar MAY choose to accept all devices, or all devices of
a particular type, at the administrator's discretion. This may a particular type, at the administrator's discretion. This could
occur when: Informing the Registrar of unique identifiers of new occur when informing the Registrar of unique identifiers of new
entities might be operationally difficult. entities might be operationally difficult.
2. The registrar may choose to accept devices that claim a unique 2. The 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 may occur when: The New Entity does not include identity. This could occur when the New Entity does not include
an IEEE 802.1AR factory installed credential. an IEEE 802.1AR factory installed credential.
3. The registrar may request nonce-less authorization tokens from 3. The registrar MAY request nonce-less Audit Tokens from the MASA
the MASA service. These tokens can then be transmitted to the service. These tokens can then be transmitted to the Registrar
Registrar and stored until they are needed during bootstrapping and stored until they are needed during bootstrapping operations.
operations. This is for use cases where target network is This is for use cases where target network is protected by an air
protected by an air gap and therefore can not contact the MASA gap and therefore can not contact the MASA service during New
service during New Entity deployment. Entity deployment.
4. The registrar MAY ignore unrecognized nonce-less Audit Log
entries. This could occur when used equipment is purchased with
a valid history being deployed in air gap networks that required
permanent Audit Tokens.
6.3. MASA security reductions 6.3. MASA security reductions
Lower security modes chosen by the MASA service effect all device Lower security modes chosen by the MASA service effect all device
deployments unless paired with strict device ownership validation, in deployments unless paired with strict device ownership validation, in
which case these modes can be provided as additional features for which case these modes can be provided as additional features for
specific customers. The MASA service can choose to run in less specific customers. The MASA service can choose to run in less
secure modes by: secure modes by:
1. Not enforcing that a Nonce is in the authorization token. This 1. Not enforcing that a Nonce is in the Audit Token. This results
results in distribution of authorization tokens that never expire in distribution of Audit Tokens that never expire and effectly
and effectly makes the Domain an always trusted entity to the New makes the Domain an always trusted entity to the New Entity
Entity during any subsequent bootstrapping attempts. That this during any subsequent bootstrapping attempts. That this occured
occured is captured in the log information so that the Domain is captured in the log information so that the Domain registrar
registrar can make appropriate security decisions when a new can make appropriate security decisions when a new device joins
device joins the domain. This is useful to support use cases the domain. This is useful to support use cases where Registrars
where Registrars might not be online during actual device might not be online during actual device deployment. Because
deployment. this results in long lived Audit Tokens and do not require the
proof that the device is online this is only accepted when the
Registrar is authenticated by the MASA server and authorized to
provide this functionality. The MASA server is RECOMMENDED to
use this functionality only in concert with Ownership Validation
tracking.
2. Not verifying ownership before responding with an authorization 2. Not verifying ownership before responding with an Audit Token.
token. Doing so relieves the vendor providing MASA services from This is expected to be a common operational model because doing
having to tracking ownership during shipping and supply chain. so relieves the vendor providing MASA services from having to
The registrar uses the log information as a defense in depth tracking ownership during shipping and supply chain and allows
strategy to ensure that this does not occur unexpectedly. For for a very low overhead MASA service. The Registrar uses the
example when purchasing used equipment a MASA response is audit log information as a defense in depth strategy to ensure
necessary for autonomic provisioning but the greatest level of that this does not occur unexpectedly (for example when
security is achieved when the MASA server is also performing purchasing new equipment the Registrar would throw an error if
ownership validation. any audit log information is reported).
7. Security Considerations 7. Security Considerations
In order to support a wide variety of use cases, devices can be In order to support a wide variety of use cases, devices can be
claimed by a registrar without proving possession of the device in claimed by a registrar without proving possession of the device in
question. This would result in a nonceless, and thus always valid, question. This would result in a nonceless, and thus always valid,
claim. Or would result in an invalid nonce being associated with a claim. Or would result in an invalid nonce being associated with a
claim. The MASA service is required to authenticate such Registrars claim. The MASA service is required to authenticate such Registrars
but no programmatic method is provided to ensure good behavior by the but no programmatic method is provided to ensure good behavior by the
MASA service. Nonceless entries into the audit log therefore MASA service. Nonceless entries into the audit log therefore
skipping to change at page 25, line 32 skipping to change at page 31, line 22
network. If the MASA server were to have allowed a significantly network. If the MASA server were to have allowed a significantly
large number of claims this might become onerous to the MASA server large number of claims this might become onerous to the MASA server
which must maintain all the extra log entries. Ensuring the registar which must maintain all the extra log entries. Ensuring the registar
is representative of a valid customer domain even without validating is representative of a valid customer domain even without validating
ownership helps to mitigate this. ownership helps to mitigate this.
It is possible for an attacker to send an authorization request to It is possible for an attacker to send an authorization request to
the MASA service directly after the real Registrar obtains an the MASA service directly after the real Registrar obtains an
authorization log. If the attacker could also force the authorization log. If the attacker could also force the
bootstrapping protocol to reset there is a theoretical opportunity bootstrapping protocol to reset there is a theoretical opportunity
for the attacker to use the authorization token to take control of for the attacker to use the Audit Token to take control of the New
the New Entity but then proceed to enrol with the target domain. To Entity but then proceed to enroll with the target domain. Possible
prevent this the MASA service is rate limited to only generate prevention mechanisms include:
authorization tokens at a rate of 1 per minute. The Registrar
therefore has at least 1 minute to get the response back to the New
Entity. [[EDNOTE: a better solution can likely be found. This text
captures the issue for now. Binding the logs via a ]] Also the
Registrar can double check the log information after enrolling the
New Entity.
The MASA service could lock a claim and refuse to issue a new token. o Per device rate limits on the MASA service ensure such timing
Or the MASA service could go offline (for example if a vendor went attacks are difficult.
o In the advent of an unexpectadly lost bootstrapping connection the
Registrar repeats the request for audit log information.
As indicated in EST [RFC7030] the connection is provisional and
untrusted until the server is successfully authorized. If the server
provides a redirect response the client MUST follow the redirect but
the connection remains provisional. If the client uses a well known
URI for contacting a well known Registrar the EST Implicit Trust
Anchor database is used as is described in RFC6125 to authenticate
the well known URI. In this case the connection is not provisional
and RFC6125 methods can be used for each subsequent redirection.
The MASA service could lock a claim and refuse to issue a new token
or the MASA service could go offline (for example if a vendor went
out of business). This functionality provides benefits such as theft out of business). This functionality provides benefits such as theft
resistance, but it also implies an operational risk. This can be resistance, but it also implies an operational risk to the Domain
mitigated by Registrars that request nonce-less authorization tokens. that Vendor behavior could limit future bootstrapping of the device
by the Domain. This can be mitigated by Registrars that request
nonce-less authorization tokens.
7.1. Trust Model 7.1. Trust Model
[[EDNOTE: (need to describe that we need to trust the device h/w. To [[EDNOTE: (need to describe that we need to trust the device h/w. To
be completed.)]] be completed.)]]
8. Acknowledgements 8. Acknowledgements
We would like to thank the various reviewers for their input, in We would like to thank the various reviewers for their input, in
particular Markus Stenberg, Brian Carpenter, Fuyu Eleven. particular Markus Stenberg, Brian Carpenter, Fuyu Eleven.
skipping to change at page 27, line 8 skipping to change at page 33, line 8
nmrg-autonomic-network-definitions-07 (work in progress), nmrg-autonomic-network-definitions-07 (work in progress),
March 2015. March 2015.
[imprinting] [imprinting]
Wikipedia, , "Wikipedia article: Imprinting", July 2015, Wikipedia, , "Wikipedia article: Imprinting", July 2015,
<https://en.wikipedia.org/wiki/Imprinting_(psychology)>. <https://en.wikipedia.org/wiki/Imprinting_(psychology)>.
[pledge] Dictionary.com, , "Dictionary.com Unabridged", July 2015, [pledge] Dictionary.com, , "Dictionary.com Unabridged", July 2015,
<http://dictionary.reference.com/browse/pledge>. <http://dictionary.reference.com/browse/pledge>.
Appendix A. Editor notes
[[EDNOTE: This section is to capturing rough notes between editors
and Anima Bootstrapping design team members. This entire section to
be removed en masse before finalization]]
Change Discussion:
03 updated figures added "ownership voucher" concepts added "request
join" state to the new entity discussions broke discovery and
identity into two sections added request join section expanded
imprint autonomic methods as per design team discussions
simplified proxy discussion as per design team discussions
clarified 'entity authorization' clarified 'claiming the new
entity' removed EAP-EST references expanded on protocol details as
per ownership validation options slight additions to security
considerations
02 Moved sections for readability, Updated introduction, simplified
functional overview to avoid distractions from optional elements,
addressed updated security considerations, fleshed out state
machines.
The following is a non-prioritized list of work items currently
identified:
o Continue to address gaps/opportunities highlighted by community
work on bootstrappping. Refs: IETF92 "Survey of Security
Bootstrapping", Aana Danping He, behcet Sarikaya. "NETCONF Zero
Touch Update for ANIMA" https://www.ietf.org/proceedings/92/
anima.html and "Bootstrapping Key Infrastructures", Pritikin,
Behringer, Bjarnason
o IN PROGRESS: Intergrate "Ownership Voucher" as a valid optional
format for the MASA response. So long as the issuance of this is
logged and captured in the log response then the basic flow and
threat model is substantially the same.
o COMPLETE (moved to simple proxy): Attempt to re-use existing work
as per the charter: Toerless notes: a) are existing [eap] options?
or too complex? or doens't work? b) our own method (e.g. EAP-
ANIMA c) if b then investigate using signaling protocol).
o
Authors' Addresses Authors' Addresses
Max Pritikin Max Pritikin
Cisco Cisco
Email: pritikin@cisco.com Email: pritikin@cisco.com
Michael C. Richardson Michael C. Richardson
Sandelman Software Works Sandelman Software Works
470 Dawson Avenue 470 Dawson Avenue
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