NETCONF Working Group K. Watsen
Internet-Draft Juniper Networks
Intended status: Standards Track M. Abrahamsson
Expires: May 4, 2017 T-Systems
October 31, 2016
Zero Touch Provisioning for NETCONF or RESTCONF based Management
draft-ietf-netconf-zerotouch-10
Abstract
This draft presents a secure technique for establishing a NETCONF or
RESTCONF connection between a newly deployed device, configured with
just its factory default settings, and its deployment specific
network management system (NMS).
Editorial Note (To be removed by RFC Editor)
This draft contains many placeholder values that need to be replaced
with finalized values at the time of publication. This note
summarizes all of the substitutions that are needed. Please note
that no other RFC Editor instructions are specified anywhere else in
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This document contains references to other drafts in progress, both
in the Normative References section, as well as in body text
throughout. Please update the following references to reflect their
final RFC assignments:
o draft-ietf-netconf-call-home
o draft-ietf-netconf-restconf
o draft-ieft-netconf-server-model
o draft-ietf-anima-bootstrapping-keyinfra
Artwork in this document contains shorthand references to drafts in
progress. Please apply the following replacements:
o "XXXX" --> the assigned RFC value for this draft
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The following one Appendix section is to be removed prior to
publication:
o Appendix A. Change Log
Status of This Memo
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 5
1.3. Requirements Language . . . . . . . . . . . . . . . . . . 6
1.4. Tree Diagram Notation . . . . . . . . . . . . . . . . . . 6
2. Guiding Principles . . . . . . . . . . . . . . . . . . . . . 7
2.1. Trust Anchors . . . . . . . . . . . . . . . . . . . . . . 7
2.2. Conveying Trust . . . . . . . . . . . . . . . . . . . . . 7
2.3. Conveying Ownership . . . . . . . . . . . . . . . . . . . 8
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3. Types of Information . . . . . . . . . . . . . . . . . . . . 8
3.1. Redirect Information . . . . . . . . . . . . . . . . . . 9
3.2. Bootstrap Information . . . . . . . . . . . . . . . . . . 10
4. Artifacts . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.1. Information Type . . . . . . . . . . . . . . . . . . . . 11
4.2. Signature . . . . . . . . . . . . . . . . . . . . . . . . 11
4.3. Ownership Voucher . . . . . . . . . . . . . . . . . . . . 11
4.4. Owner Certificate . . . . . . . . . . . . . . . . . . . . 12
4.5. Voucher Revocation . . . . . . . . . . . . . . . . . . . 12
4.6. Certificate Revocation . . . . . . . . . . . . . . . . . 13
5. Artifact Groupings . . . . . . . . . . . . . . . . . . . . . 14
5.1. Unsigned Information . . . . . . . . . . . . . . . . . . 14
5.2. Signed Information (without Revocations) . . . . . . . . 15
5.3. Signed Information (with Revocations) . . . . . . . . . . 15
6. Sources of Bootstrapping Data . . . . . . . . . . . . . . . . 16
6.1. Removable Storage . . . . . . . . . . . . . . . . . . . . 16
6.2. DNS Server . . . . . . . . . . . . . . . . . . . . . . . 17
6.3. DHCP Server . . . . . . . . . . . . . . . . . . . . . . . 19
6.4. Bootstrap Server . . . . . . . . . . . . . . . . . . . . 20
7. Workflow Overview . . . . . . . . . . . . . . . . . . . . . . 22
7.1. Onboarding and Ordering Devices . . . . . . . . . . . . . 22
7.2. Owner Stages the Network for Bootstrap . . . . . . . . . 25
7.3. Device Powers On . . . . . . . . . . . . . . . . . . . . 27
8. Device Details . . . . . . . . . . . . . . . . . . . . . . . 29
8.1. Factory Default State . . . . . . . . . . . . . . . . . . 29
8.2. Boot Sequence . . . . . . . . . . . . . . . . . . . . . . 30
8.3. Processing a Source of Bootstrapping Data . . . . . . . . 31
8.4. Validating Signed Data . . . . . . . . . . . . . . . . . 32
8.5. Processing Redirect Information . . . . . . . . . . . . . 33
8.6. Processing Bootstrap Information . . . . . . . . . . . . 34
9. RESTCONF API for Bootstrap Servers . . . . . . . . . . . . . 35
9.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 35
9.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 37
10. Security Considerations . . . . . . . . . . . . . . . . . . . 49
10.1. Immutable storage for trust anchors . . . . . . . . . . 49
10.2. Clock Sensitivity . . . . . . . . . . . . . . . . . . . 50
10.3. Blindly authenticating a bootstrap server . . . . . . . 50
10.4. Entropy loss over time . . . . . . . . . . . . . . . . . 50
10.5. Serial Numbers . . . . . . . . . . . . . . . . . . . . . 51
10.6. Sequencing Sources of Bootstrapping Data . . . . . . . . 51
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 51
11.1. The BOOTP Manufacturer Extensions and DHCP Options
Registry . . . . . . . . . . . . . . . . . . . . . . . . 51
11.1.1. DHCP v4 Option . . . . . . . . . . . . . . . . . . . 51
11.1.2. DHCP v6 Option . . . . . . . . . . . . . . . . . . . 52
11.2. The IETF XML Registry . . . . . . . . . . . . . . . . . 53
11.3. The YANG Module Names Registry . . . . . . . . . . . . . 53
12. Other Considerations . . . . . . . . . . . . . . . . . . . . 53
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13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 53
14. References . . . . . . . . . . . . . . . . . . . . . . . . . 53
14.1. Normative References . . . . . . . . . . . . . . . . . . 54
14.2. Informative References . . . . . . . . . . . . . . . . . 55
Appendix A. API Examples . . . . . . . . . . . . . . . . . . . . 57
A.1. Unsigned Redirect Information . . . . . . . . . . . . . . 57
A.2. Signed Redirect Information . . . . . . . . . . . . . . . 58
A.3. Unsigned Bootstrap Information . . . . . . . . . . . . . 61
A.4. Signed Bootstrap Information . . . . . . . . . . . . . . 63
A.5. Progress Notifications . . . . . . . . . . . . . . . . . 67
Appendix B. Artifact Examples . . . . . . . . . . . . . . . . . 69
B.1. Redirect Information . . . . . . . . . . . . . . . . . . 69
B.2. Bootstrap Information . . . . . . . . . . . . . . . . . . 69
Appendix C. Change Log . . . . . . . . . . . . . . . . . . . . . 69
C.1. ID to 00 . . . . . . . . . . . . . . . . . . . . . . . . 69
C.2. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 70
C.3. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 70
C.4. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 71
C.5. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 71
C.6. 04 to 05 . . . . . . . . . . . . . . . . . . . . . . . . 71
C.7. 05 to 06 . . . . . . . . . . . . . . . . . . . . . . . . 71
C.8. 06 to 07 . . . . . . . . . . . . . . . . . . . . . . . . 72
C.9. 07 to 08 . . . . . . . . . . . . . . . . . . . . . . . . 72
C.10. 08 to 09 . . . . . . . . . . . . . . . . . . . . . . . . 72
C.11. 09 to 10 . . . . . . . . . . . . . . . . . . . . . . . . 72
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 73
1. Introduction
A fundamental business requirement for any network operator is to
reduce costs where possible. For network operators, deploying
devices to many locations can be a significant cost, as sending
trained specialists to each site to do installations is both cost
prohibitive and does not scale.
This document defines a bootstrapping strategy enabling devices to
securely obtain bootstrapping data with no installer input, beyond
physical placement and connecting network and power cables. The
ultimate goal of this document is to enable a secure NETCONF
[RFC6241] or RESTCONF [draft-ietf-netconf-restconf] connection to the
deployment specific network management system (NMS).
1.1. Use Cases
o Connecting to a remotely administered network
This use-case involves scenarios, such as a remote branch
office or convenience store, whereby a device connects as an
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access gateway to an ISP's network. Assuming it is not
possible to customize the ISP's network to provide any
bootstrapping support, and with no other nearby device to
leverage, the device has no recourse but to reach out to an
Internet-based bootstrap server to bootstrap off of.
o Connecting to a locally administered network
This use-case covers all other scenarios and differs only in
that the device may additionally leverage nearby devices, which
may direct it to use a local service to bootstrap off of. If
no such information is available, or the device is unable to
use the information provided, it can then reach out to network
just as it would for the remotely administered network use-
case.
1.2. Terminology
This document uses the following terms:
Artifact: The term "artifact" is used throughout to represent the
any of the six artifacts defined in Section 4. These artifacts
collectively provide all the bootstrapping data a device needs.
Bootstrapping Data: The term "bootstrapping data" is used throughout
this document to refer to the collection of data that a device
may obtain from any source of bootstrapping data. Specifically,
it refers to the artifacts defined in Section 4.
Bootstrap Information: The term "bootstrap information" is used
herein to refer to one of the bootstrapping artifacts defined in
Section 4. Specifically, bootstrap information is the
bootstrapping data that guides a device to, for instance, install
a specific boot-image and commit a specific configuration.
Bootstrap Server: The term "bootstrap server" is used within this
document to mean any RESTCONF server implementing the YANG module
defined in Section 9.2.
Device: The term "device" is used throughout this document to refer
to the network element that needs to be bootstrapped. See
Section 8 for more information about devices.
Initial Secure Device Identifier (IDevID): The term "IDevID" is
defined in [Std-802.1AR-2009] as the secure device identifier
(DevID) installed on the device by the manufacturer. This
identifier is used in this document to enable a Bootstrap Server
to securely identify and authenticate a device.
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Manufacturer: The term "manufacturer is used herein to refer to the
manufacturer of a device or a delegate of the manufacturer.
Network Management System (NMS): The acronym "NMS" is used
throughout this document to refer to the deployment specific
management system that the bootstrapping process is responsible
for introducing devices to. From a device's perspective, when
the bootstrapping process has completed, the NMS is a NETCONF or
RESTCONF client.
Owner: See Rightful Owner.
Redirect Information: The term "bootstrap information" is used
herein to refer to one of the bootstrapping artifacts defined in
Section 4. Specifically, redirect information is the
bootstrapping data that directs a device to connect to a
bootstrap server.
Redirect Server: The term "redirect server" is used to refer to a
subset of bootstrap servers that only returns redirect
information. A redirect server is particularly useful when
hosted by a manufacturer, to redirect devices to deployment-
specific bootstrap servers.
Rightful Owner: The term "rightful owner" is used herein to refer to
the person or organization that purchased or otherwise owns a
device. Ownership is further described in Section 2.3.
Signed Data: The term "signed data" is used throughout to mean
either redirect information or bootstrap information that has
been signed by a device's rightful owner's private key.
Unsigned Data: The term "unsigned data" is used throughout to mean
either redirect rnformation or bootstrap information that has not
been signed by a device's rightful owner's private key.
1.3. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in the
sections below are to be interpreted as described in RFC 2119
[RFC2119].
1.4. Tree Diagram Notation
A simplified graphical representation of the data models is used in
this document. The meaning of the symbols in these diagrams is as
follows:
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o Brackets "[" and "]" enclose list keys.
o Braces "{" and "}" enclose feature names, and indicate that the
named feature must be present for the subtree to be present.
o Abbreviations before data node names: "rw" (read-write) represents
configuration data and "ro" (read-only) represents state data.
o Symbols after data node names: "?" means an optional node, "!"
means a presence container, and "*" denotes a list and leaf-list.
o Parentheses enclose choice and case nodes, and case nodes are also
marked with a colon (":").
o Ellipsis ("...") stands for contents of subtrees that are not
shown.
2. Guiding Principles
This section provides overarching principles guiding the solution
presented in this document.
2.1. Trust Anchors
A trust anchor is used in cryptography to represent an entity in
which trust is implicit and not derived. In public key
infrastructure using X.509 certificates, a root certificate is the
trust anchor, from which a chain of trust is derived. The solution
presented in this document requires that all the entities involved
(e.g., devices, bootstrap servers, NMSs) possess specific trust
anchors in order to ensure mutual authentication throughout the zero
touch bootstrapping process.
2.2. Conveying Trust
A device in its factory default state possesses a limited set of
manufacturer specified trust anchors. In this document, there are
two types of trust anchors of interest. The first type of trust
anchor is used to authenticate a secure (e.g., HTTPS) connection to,
for instance, a manufacturer-hosted Internet-based bootstrap server.
The second type of trust anchor is used to authenticate manufacturer-
signed data, such as the ownership voucher artifact described in
Section 4.3.
Using the first type of trust anchor, trust is conveyed by the device
first authenticating the server (e.g., a bootstrap server), and then
by the device trusting that the server would only provide data that
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its rightful owner staged for it to find. Thereby the device can
trust any information returned from the server.
Using the second type of trust anchor, trust is conveyed by the
device first authenticating that an artifact has been signed by its
rightful owner, and thereby can trust any information held within the
artifact.
Notably, redirect information, as described in Section 3.1, may
include more trust anchors, which illustrates another way in which
trust can be conveyed.
2.3. Conveying Ownership
The ultimate goal of this document is to enable a device to establish
a secure connection with its rightful owner's NMS. This entails the
manufacturer being able to track who is the rightful owner of a
device (not defined in this document), as well as an ability to
convey that information to devices (defined in this document).
Matching the two ways to convey trust (Section 2.2), this document
provides two ways to convey ownership, by using a trusted bootstrap
server (Section 6.4) or by using an ownership voucher (Section 4.3).
When a device connects to a trusted bootstrap server, one that was
preconfigured into its factory default configuration, it implicitly
trusts that the bootstrap server would only provide data that its
rightful owner staged for it to find. That is, ownership is conveyed
by the administrator of the bootstrap server (e.g., a manufacturer)
taking the onus of ensuring that only data configured by a device's
rightful owner is made available to the device. With this approach,
the assignment of a device to an owner is ephemeral, as the
administrator can reassign a device to another owner at any time.
When a device is presented signed bootstrapping data, it can
authenticate that its rightful owner provided the data by verifying
the signature over the data using an additional artifact defined
within this document, the ownership voucher. With this approach,
ownership is conveyed by the manufacturer (or delegate) taking the
onus of ensuring that the ownership vouchers it issues are accurate
and, in some cases, also ensuring timely voucher revocations
(Section 4.5).
3. Types of Information
This document defines two types of information, redirect information
and bootstrap information, that devices access during the
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bootstrapping process. These two types of information are described
in this section.
3.1. Redirect Information
Redirect information provides information to redirect a device to a
bootstrap server. Redirect information encodes a list of bootstrap
servers, each defined by its hostname or IP address, an optional
port, and an optional trust anchor certificate.
Redirect information is YANG modeled data formally defined by the
"redirect-information" grouping in the YANG module presented in
Section 9.2. This grouping has the tree diagram shown below. Please
see Section 1.4 for tree diagram notation.
+--:(redirect-information)
+--ro redirect-information
+--ro bootstrap-server* [address]
+--ro address inet:host
+--ro port? inet:port-number
+--ro trust-anchor? binary
Redirect information MAY be trusted or untrusted. The redirect
information is trusted whenever it is obtained via a secure
connection to a trusted bootstrap server, or whenever it is signed by
the device's rightful owner. In all other cases, the redirect
information is untrusted.
Trusted redirect information is useful for enabling a device to
establish a secure connection to a bootstrap server, which is
possible when the redirect information includes the bootstrap
server's trust anchor certificate. When a device is able to
establish a secure connection to a bootstrap server, the
bootstrapping data does not have to be signed in order to be trusted,
as described in Section 2.2.
Untrusted redirect information is useful for directing a device to a
bootstrap server where signed data has been staged for it to obtain.
When the redirect information is untrusted, the device MUST discard
any potentially included trust anchor certificates. When the
redirect information is untrusted, a device MAY establish a
provisional connection to any of the specified bootstrap servers. A
provisional connection is accomplished by the device blindly
accepting the bootstrap server's TLS certificate. In this case, the
device MUST NOT trust the bootstrap server, and data provided by the
bootstrap server MUST be signed for it to be of any use to the
device.
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How devices process redirect information is described more formally
in Section 8.5.
3.2. Bootstrap Information
Bootstrap information provides all the data necessary for a device to
bootstrap itself, in order to be considered ready to be managed
(e.g., by an NMS). As defined in this document, this data includes
information about a boot image the device MUST be running, an initial
configuration the device MUST commit, and optional scripts that, if
specified, the device MUST successfully execute.
Bootstrap information is YANG modeled data formally defined by the
"bootstrap-information" grouping in the YANG module presented in
Section 9.2. This grouping has the tree diagram shown below. Please
see Section 1.4 for tree diagram notation.
+--:(bootstrap-information)
+--ro bootstrap-information
+--ro boot-image
| +--ro name string
| +--ro (hash-algorithm)
| | +--:(sha256)
| | +--ro sha256? string
| +--ro uri* inet:uri
+--ro configuration-handling enumeration
+--ro pre-configuration-script? script
+--ro configuration?
+--ro post-configuration-script? script
Bootstrap information MUST be trusted for it to be of any use to a
device. There is no option for a device to process untrusted
bootstrap information.
Bootstrap information is trusted whenever it is obtained via a secure
connection to a trusted bootstrap server, or whenever it is signed by
the device's rightful owner. In all other cases, the bootstrap
information is untrusted.
How devices process bootstrap information is described more formally
in Section 8.6.
4. Artifacts
This document defines six artifacts that can be made available to
devices while they are bootstrapping. As will be seen in Section 6,
each source of bootstrapping information specifies a means for
providing each of the artifacts defined in this section.
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4.1. Information Type
The information type artifact encodes the essential bootstrapping
data for the device. This artifact is used to encode the redirect
information and bootstrap information types discussed in Section 3.
The information type artifact is YANG modeled data formally defined
by the "information-type" choice node in Section 9.2 and can be
encoded using any standard YANG encoding (e.g., XML, JSON).
4.2. Signature
The signature artifact is used by a device to verify that an
information type artifact was created by the device's rightful owner.
The signature is generated using the owner's private key over the
information-type artifact, in whatever encoding it is presented in
(e.g., XML, JSON, etc.). How signed data is validated is formally
described in Section 8.4.
The signature artifact is formally a PKCS#7 SignedData structure as
specified by Section 9.1 of [RFC2315], containing just the signature
(no content, certificates, or CRLs), encoded using ASN.1
distinguished encoding rules (DER), as specified in ITU-T X.690.
4.3. Ownership Voucher
The ownership voucher is used to securely identify a device's owner,
as it is known to the manufacturer. The ownership voucher is signed
by the device's manufacturer or delegate.
The ownership voucher is used by a device to verify the owner
certificate (Section 4.4) that the device SHOULD have also received,
as described in Section 5. In particular, the device verifies that
owner certificate's chain of trust includes the trusted certificate
included in the voucher, and also verifies that the owner certificate
contains an identifier matching the one specified in the voucher.
In order to validate the voucher, a device MUST verify that the
voucher was signed by the private key associated with a trusted
certificate known to the device in its factory default state, as
described in Section 8.1, and the device MUST verify that the
voucher's expression for the devices that it applies to includes the
device's unique identifier (e.g., serial number) and, for devices
that insist on verifying voucher revocation status, the device MUST
verify that the voucher has neither expired nor been revoked.
The ownership voucher artifact, including its encoding, is formally
defined in [draft-kwatsen-netconf-voucher].
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4.4. Owner Certificate
The owner certificate artifact is a certificate that is used to
identify an 'owner' (e.g., an organization), as known to a trusted
certificate authority. The owner certificate is signed by the
trusted certificate authority.
The owner certificate is used by a device to verify the signature
artifact (Section 4.2) that the device SHOULD have also received, as
described in Section 5. In particular, the device verifies signature
using the public key in the owner certificate over the information
type artifact (Section 4.1).
In order to validate the owner certificate, a device MUST verify that
the owner certificate's certificate chain includes the certificate
specified by the ownership voucher (Section 4.3) that the device
SHOULD have also received, as described in Section 5, and the device
MUST verify that owner certificate contains an identifier matching
the one specified in the voucher and, for devices that insist on
verifying certificate revocation status, the device MUST verify that
the certificate has neither expired nor been revoked.
The owner certificate artifact is formally an unsigned PKCS #7
SignedData structure as specified by RFC 2315 [RFC2315], Section 9.1,
containing just certificates (no content, signatures, or CRLs),
encoded using ASN.1 distinguished encoding rules (DER), as specified
in ITU-T X.690.
The owner certificate artifact contains, in order, the owner
certificate itself and all intermediate certificates leading up to a
trust anchor certificate. The owner certificate MAY optionally
include the trust anchor certificate.
4.5. Voucher Revocation
The voucher revocation artifact is used to verify the revocation
status of vouchers. Voucher revocations are signed by the
manufacturer or delegate (i.e. the issuer of the voucher).
Voucher revocations are generally needed when it is critical for
devices to know that assurances implied at the time the voucher was
signed are still valid at the time the voucher is being processed.
The need for devices to insist on verifying voucher revocation status
is a decision for each manufacturer. If voucher revocation status
verification is not asserted, then the ownership vouchers are
essentially forever, which may be acceptable for various kinds of
devices. If revocations are supported, then it becomes possible to
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support various scenarios such as handling a key compromise or change
in ownership.
If voucher revocations are supported, devices MAY dynamically obtain
the voucher revocation artifact (or equivalents) from an Internet
based resource. If the access to the Internet based resource is
sufficiently reliable, then there may not be a need for the voucher
revocation artifact to be supplied by any other means (e.g.,
Section 6). However, since the access may not be sufficiently
reliable, support for this artifact is defined herein.
The voucher revocation artifact is used by a device to verify the
ownership voucher (Section 4.3) that the device SHOULD have also
received, as described in Section 5. In particular, the device
verifies that the voucher revocation explicitly states either that
the given voucher is valid or that it is not invalid.
In order to validate a voucher revocation artifact, a device MUST
verify that it was signed by a private key associated with a trusted
certificate known to the device in its factory default state, as
described in Section 8.1, and the device MUST verify that the voucher
revocation hasn't expired, and the device SHOULD verify that the
revocation is sufficiently fresh, per local policy.
The voucher revocation artifact, including its encoding, is formally
defined in [draft-kwatsen-netconf-voucher].
4.6. Certificate Revocation
The certificate revocation artifact is a list of CRLS used to verify
the revocation status of owner certificates. Certificate revocations
are signed by the certificate authority (or delegate) that issued the
owner certificate.
Certificate revocations are generally needed when it is critical for
devices to know that assurances implied at the time the certificate
was signed are still valid at the time the certificate is being
processed.
The need for devices to insist on verifying certificate revocation
status is a decision for each manufacturer. If certificate
revocation status verification is not asserted, then the owner
certificates are essentially forever, which may be acceptable for
various kinds of devices. If revocations are supported, then it
becomes possible to support various scenarios such as handling a key
compromise or expiration.
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If certificate revocations are supported, devices MAY dynamically
obtain the certificate revocation artifact from an Internet based
resource (using a CRL distribution point or an OCSP responder). If
the access to the Internet based resource is sufficiently reliable,
then there may not be a need for the certificate revocation artifact
to be supplied by any other means (e.g., Section 6). However, since
the access may not be sufficiently reliable, support for this
artifact is defined herein, so that the voucher revocation artifact
can be distributed by any source of bootstrapping data.
The certificate revocation artifact is used by a device to verify the
owner certificate (Section 4.4) that the device SHOULD have also
received, as described in Section 5. In particular, the device
verifies that the certificate revocation explicitly states either
that the given certificate is valid or that it is not invalid.
In order to validate the CRLs contained with the certificate
revocation artifact, a device MUST verify that the CRL was signed by
a private key associated certificate's issuer (or delegate), and the
device MUST verify that the CRL hasn't expired, and the device SHOULD
verify that the revocation is sufficiently fresh, per local policy.
The certificate revocation artifact is formally an unsigned PKCS #7
SignedData structure as specified by RFC 2315 [RFC2315], Section 9.1,
containing just CRLs (no content, signatures, or certificates),
encoded using ASN.1 distinguished encoding rules (DER), as specified
in ITU-T X.690.
The certificate revocation artifact contains, in order, the CRL for
the owner certificate itself and the CRLs for all intermediate
certificates leading up to but not including a trust anchor
certificate.
5. Artifact Groupings
Section 4 lists all the possible bootstrapping artifacts, but only
certain groupings of these artifacts make sense to return in the
various bootstrapping situations described in this document. The
remainder of this section identifies these groupings to further
clarify how the artifacts are used.
5.1. Unsigned Information
The first grouping of artifacts is for unsigned information. That
is, when the information type artifact (Section 4.1) has not been
signed.
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Unsigned information is useful for cases when transport level
security can be used to convey trust (e.g., HTTPS), or when the
information can be processed in a provisional manner (i.e. unsigned
redirect information).
Conveying unsigned information entails communicating just one of the
six artifacts listed in Section 4, namely the information type
artifact.
List of artifacts included in this grouping:
- information type
5.2. Signed Information (without Revocations)
The second grouping of artifacts is for when the information type
artifact (Section 4.1) has been signed, without any revocation
information.
Signed information is needed when the information is obtained from an
untrusted source of bootstrapping data (Section 6) and yet it is
desired that the device be able to trust the information (i.e. no
provisional processing).
Revocation information may not need to be provided because, for
instance, the device only uses revocation information obtained
dynamically from Internet based resources. Another possible reason
may be because the device does not have a reliable clock, and
therefore the manufacturer decides to never revoke information (e.g.,
ownership assignments are forever).
Conveying signed information without revocation information entails
communicating four of the six artifacts listed in Section 4.
List of artifacts included in this grouping:
- information type
- signature
- ownership voucher
- owner certificate
5.3. Signed Information (with Revocations)
The third grouping of artifacts is for when the information type
artifact (Section 4.1) has been signed and also includes revocation
information.
Signed information, as described above, is needed when the
information is obtained from an untrusted source of bootstrapping
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data (Section 6) and yet it is desired that the device be able to
trust the information (i.e. no provisional processing).
Revocation information may need to be provided because, for instance,
the device insists on being able to verify revocations and the device
is deployed on a private network and therefore unable to obtain the
revocation information from Internet based resources.
Conveying signed information with revocation information entails
communicating all six of the artifacts listed in Section 4.
List of artifacts included in this grouping:
- information type
- signature
- ownership voucher
- owner certificate
- voucher revocations
- certificate revocations
6. Sources of Bootstrapping Data
This section defines some sources for zero touch bootstrapping data
that a device can access. The list of sources defined here is not
meant to be exhaustive. It is left to future documents to define
additional sources for obtaining zero touch bootstrapping data.
For each source defined in this section, details are given for how
each of the six artifacts listed in Section 4 is provided.
6.1. Removable Storage
A directly attached removable storage device (e.g., a USB flash
drive) MAY be used as a source of zero touch bootstrapping data.
To use a removable storage device as a source of bootstrapping data,
a device need only detect if the removable storage device is plugged
in and mount its filesystem.
Use of a removable storage device is compelling, as it doesn't
require any external infrastructure to work. It is also compelling
that the raw boot image file can be located on the removable storage
device, enabling a removable storage device to be a fully self-
standing bootstrapping solution.
A removable storage device is an untrusted source of bootstrapping
data. This means that the information stored on the removable
storage device either MUST be signed, or it MUST be information that
can be processed provisionally (e.g., unsigned redirect information).
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From an artifact perspective, since a removable storage device
presents itself as a file-system, the bootstrapping artifacts need to
be presented as files. The six artifacts defined in Section 4 are
mapped to files below.
Artifact to File Mapping:
Information Type: Mapped to a file containing a standard YANG
encoding for the YANG modeled data described in Section 4.1. A
filenaming convention SHOULD be used to indicate data encoding
(e.g., boot-info.[xml|json]).
Signature: Mapped to a file containing the binary artifact
described in Section 4.2.
Ownership Voucher: Mapped to a file containing the binary
artifact described in Section 4.3.
Owner Certificate: Mapped to a file containing the binary
artifact described in Section 4.4.
Voucher Revocation: Mapped to a file containing the binary
artifact described in Section 4.5.
Certificate Revocation: Mapped to a file containing binary
artifact described in Section 4.6.
The format of the removable storage device's filesystem and the
naming of the files are outside the scope of this document. However,
in order to facilitate interoperability, it is RECOMMENDED devices
support open and/or standards based filesystems. It is also
RECOMMENDED that devices assume a filenaming convention that enables
more than one instance of bootstrapping data to exist on a removable
storage device. The filenaming convention SHOULD be unique to the
manufacturer, in order to enable bootstrapping data from multiple
manufacturers to exist on a removable storage device.
6.2. DNS Server
A DNS server MAY be used as a source of zero touch bootstrapping
data.
Using a DNS server may be a compelling option for deployments having
existing DNS infrastructure, as it enables a touchless bootstrapping
option that does not entail utilizing an Internet based resource
hosted by a 3rd-party.
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To use a DNS server as a source of bootstrapping data, a device MAY
perform a multicast DNS [RFC6762] query searching for the service
"_zerotouch._tcp.local.". Alternatively the device MAY perform DNS-
SD [RFC6763] via normal DNS operation, using the domain returned to
it from the DHCP server; for example, searching for the service
"_zerotouch._tcp.example.com".
Unsigned DNS records (not using DNSSEC as described in [RFC6698]) are
an untrusted source of bootstrapping data. This means that the
information stored in the DNS records either MUST be signed, or it
MUST be information that can be processed provisionally (e.g.,
unsigned redirect information).
From an artifact perspective, since a DNS server presents resource
records (Section 3.2.1 of [RFC1035]), the bootstrapping artifacts
need to be presented as resource records. The six artifacts defined
in Section 4 are mapped to resource records below.
Artifact to Resource Record Mapping:
Information Type: Mapped to a TXT record called "info-type"
containing a standard YANG encoding for the YANG modeled data
described in Section 4.1. Note: no additional field is
provided to specify the encoding.
Signature: Mapped to a TXT record called "sig" containing the
base64-encoding of the binary artifact described in
Section 4.2.
Ownership Voucher: Mapped to a TXT record called "voucher"
containing the base64-encoding of the binary artifact described
in Section 4.3.
Owner Certificate: Mapped to a TXT record called "cert"
containing the base64-encoding of the binary artifact described
in Section 4.4.
Voucher Revocation: Mapped to a TXT record called "vouch-rev"
containing the base64-encoding of the binary artifact described
in Section 4.5.
Certificate Revocation: Mapped to a TXT record called "cert-rev"
that containing the base64-encoding of the binary artifact
described in Section 4.6.
TXT records have an upper size limit of 65535 bytes (Section 3.2.1 in
RFC1035), since 'RDLENGTH' is a 16-bit field. Please see
Section 3.1.3 in RFC4408 for how a TXT record can achieve this size.
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Due to this size limitation, some information type artifacts may not
fit. In particular, the bootstrap information artifact could hit
this upper bound, depending on the size of the included configuration
and scripts.
When bootstrap information is provided, it is notable that the URL
for the boot-image the device can download would have to point to
another server (e.g., http://, ftp://, etc.), as DNS servers do not
themselves distribute files.
6.3. DHCP Server
A DHCP server MAY be used as a source of zero touch bootstrapping
data.
To use a DHCP server as a source of bootstrapping data, a device need
only send a DHCP lease request to a DHCP server. However, the device
SHOULD pass the Vendor Class Identifier (option 60) field in its DHCP
lease request, so the DHCP server can return bootstrap information
shared by devices from the same vendor. However, if it is desired to
return device-specific bootstrap information, then the device SHOULD
also send the Client Identifier (option 61) field in its DHCP lease
request, so the DHCP server can select the specific bootstrap
information that has been staged for that one device.
Using a DHCP server may be a compelling option for deployments having
existing DHCP infrastructure, as it enables a touchless bootstrapping
option that does not entail utilizing an Internet based resource
hosted by a 3rd-party.
A DHCP server is an untrusted source of bootstrapping data. This
means that the information returned by the DHCP server either MUST be
signed, or it MUST be information that can be processed provisionally
(e.g., unsigned redirect information).
From an artifact perspective, since a DHCP server presents data as
DHCP options , the bootstrapping artifacts need to be presented as
DHCP options, specifically the ones specified in Section 11.1. The
six artifacts defined in Section 4 are mapped to the DHCP options
specified in Section 11.1 below.
Artifact to DHCP Option Field Mapping:
Information Type: Mapped to the DHCP option field "information-
type" containing the YANG modeled data described in
Section 4.1. The additional field "encoding" is provided to
specify the encoding used, taking the values "xml" or "json".
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Signature: Mapped to the DHCP option field "signature" containing
the binary artifact described in Section 4.2.
Ownership Voucher: Mapped to the DHCP option field "ownership-
voucher" containing the binary artifact described in
Section 4.3.
Owner Certificate: Mapped to the DHCP option field "owner-
certificate" containing the binary artifact described in
Section 4.4.
Voucher Revocation: Mapped to the DHCP option field "voucher-
revocations" containing the binary artifact described in
Section 4.5.
Certificate Revocation: Mapped to the DHCP option field
"certificate-revocations" containing the binary artifact
described in Section 4.6.
When bootstrap information is provided, it is notable that the URL
for the boot-image the device can download would have to point to
another server (e.g., http://, ftp://, etc.), as DHCP servers do not
themselves distribute files.
6.4. Bootstrap Server
A bootstrap server MAY be used as a source of zero touch
bootstrapping data. A bootstrap server is defined as a RESTCONF
([draft-ietf-netconf-restconf]) server implementing the YANG module
provided in Section 9.
Unlike any other source of bootstrap data described in this document,
a bootstrap server is not only a source of data, but it can also
receive data from devices using the YANG-defined "notification"
action statement defined in the YANG module (Section 9.2). The data
sent from devices both enables visibility into the bootstrapping
process (e.g., warnings and errors) as well as provides potentially
useful completion status information (e.g., the device's SSH host-
keys).
To use a bootstrap server as a source of bootstrapping data, a device
MUST use the RESTCONF protocol to access the YANG container node
/device/, passing its own serial number in the URL as the key to the
'device' list.
Using a bootstrap server as a source of bootstrapping data is a
compelling option as it uses transport-level security in lieu of
signed data, which may be easier to deploy in some situations.
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Additionally, the bootstrap server is able to receive notifications
from devices, which may be critical to some deployments (e.g., the
passing of the device's SSH host keys).
A bootstrap server may be trusted or an untrusted source of
bootstrapping data, depending on how the device learned about the
bootstrap server's trust anchor from a trusted source. When a
bootstrap server is trusted, the information returned from it MAY be
signed. However, when the server is untrusted, in order for its
information to be of any use to the device, the information MUST
either be signed or be information that can be processed
provisionally (e.g., unsigned redirect information).
When a device is able to trust a bootstrap server, it MUST send its
IDevID certificate in the form of a TLS client certificate, and it
MUST send notifications to the bootstrap server. When a device is
not able to trust a bootstrap server, it MUST NOT send its IDevID
certificate in the form of a TLS client certificate, and it MUST NOT
send any notifications to the bootstrap server.
From an artifact perspective, since a bootstrap server presents data
as a YANG-modeled data, the bootstrapping artifacts need to be mapped
to nodes in the YANG module. The six artifacts defined in Section 4
are mapped to bootstrap server nodes defined in Section 9.2 below.
Artifact to Bootstrap Server Node Mapping:
Information Type: Mapped to the choice node /device/information-
type.
Signature: Mapped to the leaf node /device/signature.
Ownership Voucher: Mapped to the leaf node /device/ownership-
voucher.
Owner Certificate: Mapped to the leaf node /device/owner-
certificate.
Voucher Revocations: Mapped to the leaf node /device/voucher-
revocation.
Certificate Revocations: Mapped to the leaf-list node /device/
certificate-revocation.
While RESTCONF servers typically support a nested hierarchy of
resources, zero touch bootstrap servers only need to support the
paths /device and /device/notification. The processing instructions
provided in Section 8.3 only uses these two URLs.
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7. Workflow Overview
The zero touch solution presented in this document is conceptualized
to be composed of the workflows described in this section.
Implementations MAY vary in details. Each diagram is followed by a
detailed description of the steps presented in the diagram, with
further explanation on how implementations may vary.
7.1. Onboarding and Ordering Devices
The following diagram illustrates key interactions that may occur
from when a prospective owner enrolls in a manufacturer's zero touch
program to when the manufacturer ships devices for an order placed by
the prospective owner.
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+-----------+
+------------+ |Prospective| +---+
|Manufacturer| | Owner | |NMS|
+------------+ +-----------+ +---+
| | |
| | |
| 1. initiate enrollment | |
#<-----------------------------| |
# | |
# | |
# IDevID trust anchor | |
#-----------------------------># set IDevID trust anchor |
# #--------------------------->|
# | |
# bootstrap server | |
# account credentials | |
#-----------------------------># set credentials |
# #--------------------------->|
# | |
# | |
# owner certificate | |
#-----------------------------># set certificate |
| #--------------------------->|
| | |
| | |
| 2. place device order | |
|<-----------------------------# model devices |
| #--------------------------->|
| | |
| 3. ship devices and send | |
| device identifiers and | |
| ownership vouchers | |
|-----------------------------># set device identifiers |
| # and ownership vouchers |
| #--------------------------->|
| | |
Each numbered item below corresponds to a numbered item in the
diagram above.
1. A prospective owner of a manufacturer's devices, or an existing
owner that wishes to start using zero touch for future device
orders, initiates an enrollment process with the manufacturer or
delegate. This process includes the following:
* Regardless how the prospective owner intends to bootstrap
their devices, they will always obtain from the manufacturer
or delegate the trust anchor certificate for its device's
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IDevID certificates. This certificate will need to be
installed on the prospective owner's NMS so that the NMS can
subsequently authenticate the device's IDevID certificates.
* If the manufacturer hosts an Internet based bootstrap server
(e.g., a redirect server) such as described in Section 6.4,
then credentials necessary to configure the bootstrap server
would be provided to the prospective owner. If the bootstrap
server is configurable through an API (outside the scope of
this document), then the credentials might be installed on the
prospective owner's NMS so that the NMS can subsequently
configure the manufacturer-hosted bootstrap server directly.
* If the manufacturer's devices are able to validate signed data
(Section 8.4), then the manufacturer, acting as a certificate
authority, may additionally sign an owner certificate for the
prospective owner. Alternatively, and not depicted, the owner
may obtain an owner certificate from a manufacturer-trusted
3rd-party certificate authority, and report that certificate
to the manufacturer. How the owner certificate is used to
enable devices to validate signed bootstrapping data is
described in Section 8.4. Assuming the prospective owner's
NMS is able to prepare and sign the bootstrapping data, the
owner certificate would be installed on the NMS at this time.
2. Some time later, the prospective owner places an order with the
manufacturer (or delegate), perhaps with a special flag checked
for zero touch handling. At this time, or perhaps before placing
the order, the owner may model the devices in their NMS, creating
virtual objects for the devices with no real-world device
associations. For instance the model can be used to simulate the
device's location in the network and the configuration it should
have when fully operational.
3. When the manufacturer or delegate fulfills the order, shipping
the devices to their intended locations, they may notify the
owner of the devices's unique identifiers (e.g., serial numbers)
and shipping destinations, which the owner may use to stage the
network for when the devices power on. Additionally, the
manufacturer may send one or more ownership vouchers,
cryptographically assigning ownership of those devices to the
rightful owner. The owner may set this information on their NMS,
perhaps binding specific modeled devices to the unique
identifiers and ownership vouchers.
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7.2. Owner Stages the Network for Bootstrap
The following diagram illustrates how an owner might stage the
network for bootstrapping devices.
+----------+ +------------+
|Deployment| |Manufacturer| +------+ +------+
| Specific | | Hosted | | Local| | Local| +---------+
+---+ |Bootstrap | | Bootstrap | | DNS | | DHCP | |Removable|
|NMS| | Server | | Server | |Server| |Server| | Storage |
+---+ +----------+ +------------+ +------+ +------+ +---------+
| | | | | |
activate | | | | | |
modeled | | | | | |
1. device | | | | | |
----------->| | | | | |
| 2. (optional) | | | |
| configure | | | |
| bootstrap | | | |
| server | | | |
|------->| | | | |
| | | | | |
| 3. (optional) configure | | |
| bootstrap server | | | |
|--------------------->| | | |
| | | | | |
| | | | | |
| 4. (optional) configure DNS server| | |
|---------------------------------->| | |
| | | | | |
| | | | | |
| 5. (optional) configure DHCP server | |
|------------------------------------------->| |
| | | | | |
| | | | | |
| 6. (optional) store bootstrapping artifacts on media |
|----------------------------------------------------->|
| | | | | |
| | | | | |
Each numbered item below corresponds to a numbered item in the
diagram above.
1. Having previously modeled the devices, including setting their
fully operational configurations and associating both device
identifiers (e.g., serial numbers) and ownership vouchers, the
owner "activates" one or more modeled devices. That is, the
owner tells the NMS to perform the steps necessary to prepare for
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when the real-world devices power up and initiate the
bootstrapping process. Note that, in some deployments, this step
might be combined with the last step from the previous workflow.
Here it is depicted that an NMS performs the steps, but they may
be performed manually or through some other mechanism.
2. If it is desired to use a deployment specific bootstrap server,
it MUST be configured to provide the bootstrapping information
for the specific devices. Configuring the bootstrap server MAY
occur via a programmatic API not defined by this document.
Illustrated here as an external component, the bootstrap server
MAY be implemented as an internal component of the NMS itself.
3. If it is desired to use a manufacturer (or delegate) hosted
bootstrap server, it MUST be configured to provide the
bootstrapping information for the specific devices. The
configuration MUST be either redirect or bootstrap information.
That is, either the manufacturer hosted bootstrap server will
redirect the device to another bootstrap server, or provide the
device with its bootstrapping information itself. The types of
bootstrapping information the manufacturer hosted bootstrap
server supports MAY vary by implementation; some implementations
may only support redirect information, or only support bootstrap
information, or support both redirect and bootstrap information.
Configuring the bootstrap server MAY occur via a programmatic API
not defined by this document.
4. If it is desired to use a DNS server to supply bootstrapping
information, a DNS server needs to be configured. If multicast
DNS-SD is desired, then the server MUST reside on the local
network, otherwise the DNS server MAY reside on a remote network.
Please see Section 6.2 for more information about how to
configure DNS servers. Configuring the DNS server MAY occur via
a programmatic API not defined by this document.
5. If it is desired to use a DHCP server to supply bootstrapping
data, a DHCP server needs to be configured. The DHCP server may
be accessed directly or via a DHCP relay. Please see Section 6.3
for more information about how to configure DHCP servers.
Configuring the DHCP server MAY occur via a programmatic API not
defined by this document.
6. If it is desired to use a removable storage device (e.g., USB
flash drive) to supply bootstrapping information, the information
would need to be placed onto it. Please see Section 6.1 for more
information about how to configure a removable storage device.
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7.3. Device Powers On
The following diagram illustrates the sequence of activities that
occur when a device powers on.
+----------+
+-----------+ |Deployment|
| Source of | | Specific |
+------+ | Bootstrap | |Bootstrap | +---+
|Device| | Data | | Server | |NMS|
+------+ +-----------+ +----------+ +---+
| | | |
| | | |
| 1. if running a modified (not | | |
| factory default) configuration, | | |
| then exit. | | |
| | | |
| 2. for each source supported, check | | |
|------------------------------------->| | |
| | | |
| 3. if bootstrap-information found, | | |
| initialize self and, only if | | |
| source is a bootstrap server, | | |
| send notifications | | |
|-------------------------------------># | |
| # webhook | |
| #----------------------->|
| | |
| 4. else if redirect-information found, for | |
| each bootstrap server specified, check | |
|-+-------------------------------------------------->| |
| | | |
| | if more redirect-information is found, recurse | |
| | (not depicted), else if bootstrap-information | |
| | found, initialize self and post notifications | |
| +--------------------------------------------------># |
| # webhook |
| #-------->|
|
| 5. retry sources and/or wait for manual provisioning.
|
The interactions in the above diagram are described below.
1. Upon power being applied, the device's bootstrapping logic first
checks to see if it is running in its factory default state. If
it is in a modified state, then the bootstrapping logic exits and
none of the following interactions occur.
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2. For each source of bootstrapping data the device supports,
preferably in order of closeness to the device (e.g., removable
storage before Internet based servers), the device checks to see
if there is any bootstrapping data for it there.
3. If bootstrap-information is found, the device initializes itself
accordingly (e.g., installing a boot-image and committing an
initial configuration). If the source is a bootstrap server, and
the bootstrap server can be trusted (i.e., TLS-level
authentication), the device also sends progress notifications to
the bootstrap server.
* The contents of the initial configuration SHOULD configure an
administrator account on the device (e.g., username, ssh-rsa
key, etc.) and SHOULD configure the device either to listen
for NETCONF or RESTCONF connections or to initiate call home
connections ([draft-ietf-netconf-call-home]).
* If the bootstrap server supports forwarding device
notifications to external systems (e.g., via a webhook), the
"bootstrap-complete" notification (Section 9.2) informs the
external system to know when it can, for instance, initiate a
connection to the device (assuming it knows the device's
address and the device was configured to listen for
connections). To support this further, the bootstrap-complete
notification also relays the device's SSH host keys and/or TLS
certificates, with which the external system can use to
authenticate subsequent connections to the device.
If the device is ever able to complete the bootstrapping process
successfully (i.e., no longer running its factory default
configuration), it exits the bootstrapping logic without
considering any additional sources of bootstrapping data.
4. Otherwise, if redirect-information is found, the device iterates
through the list of specified bootstrap servers, checking to see
if there is any bootstrapping data for it on them. If the
bootstrap server returns more redirect-information, then the
device processes it recursively. Otherwise, if the bootstrap
server returns bootstrap-information, the device processes it
following the description provided in (3) above.
5. After having tried all supported sources of bootstrapping data,
the device MAY retry again all the sources and/or provide
manageability interfaces for manual configuration (e.g., CLI,
HTTP, NETCONF, etc.). If manual configuration is allowed, and
such configuration is provided, the device MUST immediately cease
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trying to obtain bootstrapping data, as it would then no longer
be in running its factory default configuration.
8. Device Details
Devices supporting the bootstrapping strategy described in this
document MUST have the preconfigured factory default state and
bootstrapping logic described in the following sections.
8.1. Factory Default State
+------------------------------------------------------------------+
| <device> |
| |
| +----------------------------------------------------------+ |
| | <read-only storage> | |
| | | |
| | 1. IDevID cert & associated intermediate certificate(s) | |
| | 2. list of trusted Internet based bootstrap servers | |
| | 3. list of trust anchor certs for bootstrap servers | |
| | 4. trust anchor cert for ownership vouchers | |
| +----------------------------------------------------------+ |
| |
| +----------------------+ |
| | <secure storage> | |
| | | |
| | 5. private key | |
| +----------------------+ |
| |
+------------------------------------------------------------------+
Each numbered item below corresponds to a numbered item in the
diagram above.
1. Devices MUST be manufactured with an initial device identifier
(IDevID), as defined in [Std-802.1AR-2009]. The IDevID is an
X.509 certificate, encoding the device's unique device identifier
(e.g., serial number). The device MUST also possess any
intermediate certificates between the IDevID certificate and the
manufacturer's IDevID trust anchor certificate, which is provided
to prospective owners separately (e.g., Section 7.1).
2. Devices that support loading bootstrapping data from an Internet-
based bootstrap server (see Section 6.4) MUST be manufactured
with a configured list of trusted bootstrap servers. Consistent
with redirect information (Section 3.1, each bootstrap server MAY
be identified by its hostname or IP address, and an optional
port.
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3. Devices that support loading bootstrapping data from an Internet-
based bootstrap server (see Section 6.4) MUST also be
manufactured with a list of trust anchor certificates that can be
used for X.509 certificate path validation ([RFC6125], Section 6)
on the bootstrap server's TLS server certificate.
4. Devices that support loading owner signed data (see Section 1.2)
MUST also be manufactured with the trust anchor certificate for
the ownership vouchers.
5. Device MUST be manufactured with a private key that corresponds
to the public key encoded in the device's IDevID certificate.
This private key SHOULD be securely stored, ideally by a
cryptographic processor (e.g., a TPM).
8.2. Boot Sequence
A device claiming to support the bootstrapping strategy defined in
this document MUST support the boot sequence described in this
section.
Power On
|
v No
1. Running default config? --------> Boot normally
|
| Yes
v
2. For each supported source of bootstrapping data,
try to load bootstrapping data from the source
|
|
v Yes
3. Able to bootstrap off any source? -----> Run with new configuration
|
| No
v
4. Loop and/or wait for manual provisioning.
Each numbered item below corresponds to a numbered item in the
diagram above.
1. When the device powers on, it first checks to see if it is
running the factory default configuration. If it is running a
modified configuration, then it boots normally.
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2. The device iterates over its list of sources for bootstrapping
data (Section 6). Details for how to processes a source of
bootstrapping data are provided in Section 8.3.
3. If the device is able to bootstrap itself off any of the sources
of bootstrapping data, it runs with the new bootstrapped
configuration.
4. Otherwise the device MAY loop back through the list of
bootstrapping sources again and/or wait for manual provisioning.
8.3. Processing a Source of Bootstrapping Data
This section describes a recursive algorithm that a device claiming
to support the bootstrapping strategy defined in this document MUST
use to authenticate bootstrapping data. A device enters this
algorithm for each new source of bootstrapping data. The first time
the device enters this algorithm, it MUST initialize a conceptual
trust state variable, herein referred to as "trust-state", to FALSE.
The ultimate goal of this algorithm is for the device to process
bootstrap information (Section 3.2) while the trust-state variable is
TRUE.
If the data source is a bootstrap server, and the device is able to
authenticate the server using X.509 certificate path validation
([RFC6125], Section 6) to one of the device's preconfigured trust
anchors, or to a trust anchor that it learned from a previous step,
then the device MUST set trust-state to TRUE.
If trust-state is TRUE, when connecting to the bootstrap server, the
device MUST use its IDevID certificate for client certificate based
authentication and MUST POST progress notifications using the
bootstrap server's "notification" action. Otherwise, if trust-state
is FALSE, when connecting to the bootstrap server, the device MUST
NOT use its IDevID certificate for a client certificate based
authentication and MUST NOT POST progress notifications using the
bootstrap server's "notification" action.
When accessing a bootstrap server, the device MUST only access its
top-level resource, to obtain all the data staged for it in one GET
request, so that it can determine if the data is signed or not, and
thus act accordingly. If trust-state is TRUE, then the device MAY
also accesses the bootstrap servers 'notification' resource for the
device.
For any source of bootstrapping data (e.g., Section 6), if the data
is signed and the device is able to validate the signed data using
the algorithm described in Section 8.4, then the device MUST set
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trust-state to TRUE, else the device MUST set trust-state to FALSE.
Note, this is worded to cover the special case when signed data is
returned even from a trusted bootstrap server.
If the data is bootstrap information (not redirect information), and
trust-state is FALSE, the device MUST exit the recursive algorithm,
returning to the state machine described in Section 8.2. Otherwise,
the device MUST attempt to process the bootstrap information as
described in Section 8.6. In either case, success or failure, the
device MUST exit the recursive algorithm, returning to the state
machine described in Section 8.2, the only difference being in how it
responds to the "Able to bootstrap off any source?" conditional
described in that state machine.
If the data is redirect information, the device MUST process the
redirect information as described in Section 8.5. This is the
recursion step, it will cause to device to reenter this algorithm,
but this time the data source will most definitely be a bootstrap
server, as that is all redirect information is able to do.
8.4. Validating Signed Data
Whenever a device is presented signed data from an untrusted source,
it MUST validate the signed data as described in this section. If
the signed data is provided by a trusted source, a redundant trust
case, the device MAY skip verifying the signature.
Whenever there is signed data, the device MUST also be provided an
ownership voucher and an owner certificate. Depending on
circumstances, the device MAY also be provided certificate and
voucher revocations. How all the needed artifacts are provided for
each source of bootstrapping data is defined in Section 6.
The device MUST first authenticate the ownership voucher by
validating the signature on it to one of its preconfigured trust
anchors (see Section 8.1) and verify that the voucher contains the
device's unique identifier (e.g., serial number). If the device
insists on verifying revocation status, it MUST also verify that the
voucher isn't expired or has been revoked. If the authentication of
the voucher is successful, the device extracts the rightful owner's
identity from the voucher for use in the next step.
Next the device MUST authenticate the owner certificate by performing
X.509 certificate path validation on it, and by verifying that the
certificate is both identified by the voucher and also has in its
chain of trust the certificate identified by the voucher. If the
device insists on verifying revocation status, it MUST also verify
that none of the certificates in the chain of certificates have been
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revoked or expired. If the authentication of the certificate is
successful, the device extracts the owner's public key from the
certificate for use in the next step.
Finally the device MUST verify the signature over 'information type'
artifact was generated by the private key matching the public key
extracted from the owner certificate in the previous step.
When the device receives the signed data from a bootstrap server, the
device MUST use text-level operations to extract the 'information-
type' node from the parent 'device' node in the response in order to
verify the signature. It is not important if the extracted text is a
valid YANG encoding in order to verify the signature.
If any of these steps fail, then the device MUST mark the data as
invalid and not perform any of the subsequent steps.
8.5. Processing Redirect Information
In order to process redirect information (Section 3.1), the device
MUST follow the steps presented in this section.
Processing redirect information is straightforward. The device
sequentially steps through the list of provided bootstrap servers
until it can find one it can bootstrap off of.
If a hostname is provided, and the hostname's DNS resolution is to
more than one IP address, the device MUST attempt to connect to all
of the DNS resolved addresses at least once, before moving on to the
next bootstrap server. If the device is able to obtain bootstrapping
data from any of the DNS resolved addresses, it MUST immediately
process that data, without attempting to connect to any of the other
DNS resolved addresses.
If the redirect information is trusted (e.g., trust-state is TRUE),
and the bootstrap server entry contains a trust anchor certificate,
then the device MUST authenticate the bootstrap server using X.509
certificate path validation ([RFC6125], Section 6) to the specified
trust anchor. If the device is unable to authenticate the bootstrap
server to the specified trust anchor, the device MUST NOT attempt a
provisional connection to the bootstrap server (i.e., by blindly
accepting its server certificate).
If the redirect information is untrusted (e.g., trust-state is
FALSE), the device MUST discard any trust anchors provided by the
redirect information and establish a provisional connection to the
bootstrap server (i.e., by blindly accepting its TLS server
certificate).
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8.6. Processing Bootstrap Information
In order to process bootstrap information (Section 3.2), the device
MUST follow the steps presented in this section.
When processing bootstrap information, the device MUST first process
the boot image information, then execute the pre-configuration script
(if any), then commit the initial configuration, and then execute the
script (if any), in that order. If the device encounters an error at
any step, it MUST NOT proceed to the next step.
First the device MUST determine if the image it is running satisfies
the specified boot image criteria (e.g., name or fingerprint match).
If it does not, the device MUST download, verify, and install the
specified boot image, and then reboot. To verify the boot image, the
device MUST check that the boot image file matches the fingerprint
(e.g., sha256) supplied by the bootstrapping information. Upon
rebooting, the device MUST still be in its factory default state,
causing the bootstrapping process to run again, which will eventually
come to this very point, but this time the device's running image
will satisfy the specified criteria, and thus the device will move to
processing the next step.
Next, for devices that support executing scripts, if a pre-
configuration script has been specified, the device MUST execute the
script and check its exit status code to determine if had any
warnings or errors. In the case of errors, the device MUST reset
itself in such a way that force the reinstallation of its boot image,
thereby wiping out any bad state the script might have left behind.
Next the device commits the provided initial configuration. Assuming
no errors, the device moves to processing the next step.
Again, for devices that support executing scripts, if a post-
configuration script has been specified, the device MUST execute the
script and check its exit status code to determine if it had any
warnings or errors. In the case of errors, the device MUST reset
itself in such a way that force the reinstallation of its boot image,
thereby wiping out any bad state the script might have left behind.
At this point, the device has completely processed the bootstrapping
data and is ready to be managed. If the device obtained the
bootstrap information from a trusted bootstrap server, the device
MUST send the 'bootstrap-complete' notification now.
At this point the device is configured and no longer running its
factory default configuration. Notably, if the bootstrap information
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configured the device it initiate a call home connection, the device
would proceed to do so now.
9. RESTCONF API for Bootstrap Servers
This section defines a YANG ([RFC6020]) module that is used to define
the RESTCONF ([draft-ietf-netconf-restconf]) API used by the
bootstrap server defined in Section 6.4. Examples illustrating this
API in use are provided in Appendix A.
9.1. Tree Diagram
The following tree diagram provides an overview for the bootstrap
server RESTCONF API. The syntax used for this tree diagram is
described in Section 1.4.
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module: ietf-zerotouch-bootstrap-server
+--rw device* [unique-id]
+--rw unique-id string
+--rw (information-type)
| +--:(redirect-information)
| | +--rw redirect-information
| | +--rw bootstrap-server* [address]
| | +--rw address inet:host
| | +--rw port? inet:port-number
| | +--rw trust-anchor? binary
| +--:(bootstrap-information)
| +--rw bootstrap-information
| +--rw boot-image
| | +--rw name string
| | +--rw (hash-algorithm)
| | | +--:(sha256)
| | | +--rw sha256? string
| | +--rw uri* inet:uri
| +--rw configuration-handling? enumeration
| +--rw pre-configuration-script? script
| +--rw configuration?
| +--rw post-configuration-script? script
+--rw signature? binary
+--rw ownership-voucher? binary
+--rw owner-certificate? binary
+--rw voucher-revocation? binary
+--rw certificate-revocation? binary
+---x notification
+---w input
+---w notification-type enumeration
+---w message? string
+---w ssh-host-keys
| +---w ssh-host-key*
| +---w format enumeration
| +---w key-data string
+---w trust-anchors
+---w trust-anchor*
+---w protocol* enumeration
+---w certificate binary
In the above diagram, notice that all of the protocol accessible
nodes are read-only, to assert that devices can only pull data from
the bootstrap server.
Also notice that the module defines an action statement, which
devices use to provide progress notifications to the bootstrap
server.
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9.2. YANG Module
The bootstrap server's device-facing API is normatively defined by
the YANG module defined in this section.
Note: the module defined herein uses data types defined in [RFC2315],
[RFC5280], [RFC6234], [RFC6991], and [draft-kwatsen-netconf-voucher].
<CODE BEGINS> file "ietf-zerotouch-bootstrap-server@2016-10-31.yang"
module ietf-zerotouch-bootstrap-server {
yang-version "1.1";
namespace
"urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server";
prefix "ztbs";
import ietf-inet-types {
prefix inet;
reference "RFC 6991: Common YANG Data Types";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Kent Watsen
<mailto:kwatsen@juniper.net>";
description
"This module defines an interface for bootstrap servers, as defined
by RFC XXXX: Zero Touch Provisioning for NETCONF or RESTCONF based
Management.
Copyright (c) 2014 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, is permitted pursuant to, and subject to the license
terms contained in, the Simplified BSD License set forth in Section
4.c of the IETF Trust's Legal Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the RFC
itself for full legal notices.";
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revision "2016-10-31" {
description
"Initial version";
reference
"RFC XXXX: Zero Touch Provisioning for NETCONF or RESTCONF based
Management";
}
list device {
key unique-id;
description
"A device's record entry. This is the only RESTCONF resource
that a device will GET, as described in Section 8.2 in RFC XXXX.
Getting just this top-level node provides a device with all the
data it needs in a single request.";
reference
"RFC XXXX: Zero Touch Provisioning for NETCONF or
RESTCONF based Management";
leaf unique-id {
type string;
description
"A unique identifier for the device (e.g., serial number).
Each device accesses its bootstrapping record by its unique
identifier.";
}
choice information-type {
mandatory true;
description
"This choice statement ensures the response only contains
redirect-information or bootstrap-information. Note that
this is the only mandatory true node, as the other nodes
are not needed when the device trusts the bootstrap server,
in which case the data does not need to be signed.";
container redirect-information {
description
"This is redirect information, as described in Section 3.1
in RFC XXXX. Its purpose is to redirect a device to another
bootstrap server.";
reference
"RFC XXXX: Zero Touch Provisioning for NETCONF or RESTCONF
based Management";
list bootstrap-server {
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key address;
description
"A bootstrap server entry.";
leaf address {
type inet:host;
mandatory true;
description
"The IP address or hostname of the bootstrap server the
device should redirect to.";
}
leaf port {
type inet:port-number;
default 443;
description
"The port number the bootstrap server listens on.";
}
leaf trust-anchor { //should there be two fields like voucher?
type binary;
description
"An X.509 v3 certificate structure as specified by RFC
5280, Section 4, encoded using ASN.1 distinguished
encoding rules (DER), as specified in ITU-T X.690. A
certificate that a device can use as a trust anchor
to authenticate the bootstrap server it is being
redirected to.";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile.
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
}
}
container bootstrap-information {
description
"This is bootstrap information, as described in Section 3.2 in
RFC XXXX. Its purpose is to provide the device everything it
needs to bootstrap itself.";
reference
"RFC XXXX: Zero Touch Provisioning for NETCONF or RESTCONF
based Management";
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container boot-image {
description
"Specifies criteria for the boot image the device MUST
be running.";
leaf name { // maybe this should be a regex?
type string;
mandatory true;
description
"The name of a software image that the device MUST
be running in order to process the remaining nodes.";
}
choice hash-algorithm {
mandatory true;
description
"Identifies the hash algorithm used.";
leaf sha256 {
type string;
description
"The hex-encoded SHA-256 hash over the boot
image file. This is used by the device to
verify a downloaded boot image file.";
reference
"RFC 6234: US Secure Hash Algorithms.";
}
}
leaf-list uri {
type inet:uri;
min-elements 1;
description
"An ordered list of URIs to where the boot-image file MAY
be obtained. Deployments MUST know in which URI schemes
(http, ftp, etc.) a device supports. If a secure scheme
(e.g., https) is provided, a device MAY establish a
provisional connection to the server, by blindly
accepting the server's credentials (e.g., its TLS
certificate)";
}
}
leaf configuration-handling {
type enumeration {
enum merge {
description
"Merge configuration into existing running configuration.";
}
enum replace {
description
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"Replace existing running configuration with the passed
configuration.";
}
}
description
"This enumeration indicates how the server should process
the provided configuration. When not specified, the device
MAY determine how to process the configuration using other
means (e.g., vendor-specific metadata).";
}
leaf pre-configuration-script {
type script;
description
"A script that, when present, is executed before the
configuration has been processed.";
}
anydata configuration {
must "../configuration-handling";
description
"Any configuration data model known to the device. It may
contain manufacturer-specific and/or standards-based data
models.";
}
leaf post-configuration-script {
type script;
description
"A script that, when present, is executed after the
configuration has been processed.";
}
}
}
leaf signature {
type binary;
must "../information-type" {
description
"An information type must be present whenever an
signature is present.";
}
description
"A PKCS#7 SignedData structure, as specified by Section 9.1
of RFC 2315, containing just the signature (no content,
certificates, or CRLs), encoded using ASN.1 distinguished
encoding rules (DER), as specified in ITU-T X.690.
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This signature is generated by the device's owner using
the private key associated with the owner certificate
over the information-type node, exactly as it's presented
to the device. The device MUST use text-level operations
to extract the information-type node from the larger
'device' response in order to verify it. It is not
important if the extracted text is itself a valid
encoding (e.g., XML or JSON).";
reference
"RFC 2315:
PKCS #7: Cryptographic Message Syntax Version 1.5
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
leaf ownership-voucher {
type binary;
must "../signature" {
description
"A signature must be present whenever an ownership voucher
is presented.";
}
must "../owner-certificate" {
description
"An owner certificate must be present whenever an ownership
voucher is presented.";
}
description
"A 'voucher' structure, per draft-kwatsen-netconf-voucher.
The voucher needs to reference the device's unique identifier
and also specify the owner certificate's identity and a CA
certificate in the owner certificate's chain of trust.";
reference
"draft-kwatsen-netconf-voucher:
Voucher and Voucher Revocation Profiles for Bootstrapping
Protocols";
}
leaf owner-certificate {
type binary;
must "../signature" {
description
"A signature must be present whenever an owner certificate
is presented.";
}
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must "../ownership-voucher" {
description
"An ownership voucher must be present whenever an owner
certificate is presented.";
}
description
"An unsigned PKCS #7 SignedData structure, as specified
by Section 9.1 in RFC 2315, containing just certificates
(no content, signatures, or CRLs), encoded using ASN.1
distinguished encoding rules (DER), as specified in
ITU-T X.690.
This structure contains, in order, the owner certificate
itself and all intermediate certificates leading up to a
trust anchor certificate. The owner certificate MAY
optionally include the trust anchor certificate.";
reference
"RFC 2315:
PKCS #7: Cryptographic Message Syntax Version 1.5.
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
leaf voucher-revocation {
type binary;
must "../ownership-voucher" {
description
"An ownership voucher must be present whenever a voucher
revocation is presented.";
}
description
"A 'voucher-revocation' structure, as defined in
draft-kwatsen-netconf-voucher. The voucher revocation
definitively states whether a voucher is valid or not.";
reference
"draft-kwatsen-netconf-voucher:
Voucher and Voucher Revocation Profiles for Bootstrapping
Protocols";
}
leaf certificate-revocation {
type binary;
must "../owner-certificate" {
description
"An owner certificate must be present whenever an voucher
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revocation is presented.";
}
description
"An unsigned PKCS #7 SignedData structure, as specified by
Section 9.1 in RFC 2315, containing just CRLs (no content,
signatures, or certificates), encoded using ASN.1
distinguished encoding rules (DER), as specified in
ITU-T X.690.
This structure contains, in order, the CRL for the owner
certificate itself and the CRLs for all intermediate
certificates leading up to but not including a trust
anchor certificate.";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile.
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
action notification {
input {
leaf notification-type {
type enumeration {
enum bootstrap-initiated {
description
"Indicates that the device has just accessed the
bootstrap server. The 'message' field below MAY
contain any additional information that the
manufacturer thinks might be useful.";
}
enum validation-error {
description
"Indicates that the device had an issue validating
the response from the bootstrap server. The
'message' field below SHOULD indicate the specific
error. This message also indicates that the device
has abandoned trying to bootstrap off this bootstrap
server.";
}
enum signature-validation-error {
description
"Indicates that the device had an issue validating the
bootstrapping data. For instance, this could be due
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to the device expecting signed data, but only found
unsigned data, or because the ownership voucher didn't
include the device's unique identifier, or because the
signature didn't match. The 'message' field below
SHOULD indicate the specific error. This message also
indicates that the device has abandoned trying to
bootstrap off this bootstrap server.";
}
enum image-mismatch {
description
"Indicates that the device has determined that its
running image does not match the specified criteria.
The 'message' field below SHOULD indicate both what
image the device is currently running.";
}
enum image-download-error {
description
"Indicates that the device had an issue downloading
the image, which could be for reasons such as a file
server being unreachable to the downloaded file
being the incorrect file (signature mismatch). The
'message' field about SHOULD indicate the specific
error. This message also indicates that the device
has abandoned trying to bootstrap off this bootstrap
server.";
}
enum pre-script-warning {
description
"Indicates that the device obtained a greater than
zero exit status code from the script when it was
executed. The 'message' field below SHOULD indicate
both the resulting exit status code, as well as
capture any stdout/stderr messages the script may
have produced.";
}
enum pre-script-error {
description
"Indicates that the device obtained a less than zero
exit status code from the script when it was executed.
The 'message' field below SHOULD indicate both the
resulting exit status code, as well as capture any
stdout/stderr messages the script may have produced.
This message also indicates that the device has
abandoned trying to bootstrap off this bootstrap
server.";
}
enum config-warning {
description
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"Indicates that the device obtained warning messages
when it committed the initial configuration. The
'message' field below SHOULD indicate the warning
messages that were generated.";
}
enum config-error {
description
"Indicates that the device obtained error messages
when it committed the initial configuration. The
'message' field below SHOULD indicate the error
messages that were generated. This message also
indicates that the device has abandoned trying to
bootstrap off this bootstrap server.";
}
enum post-script-warning {
description
"Indicates that the device obtained a greater than
zero exit status code from the script when it was
executed. The 'message' field below SHOULD indicate
both the resulting exit status code, as well as
capture any stdout/stderr messages the script may
have produced.";
}
enum post-script-error {
description
"Indicates that the device obtained a less than zero
exit status code from the script when it was executed.
The 'message' field below SHOULD indicate both the
resulting exit status code, as well as capture any
stdout/stderr messages the script may have produced.
This message also indicates that the device has
abandoned trying to bootstrap off this bootstrap
server.";
}
enum bootstrap-complete {
description
"Indicates that the device successfully processed the
all the bootstrapping data and that it is ready to
be managed. The 'message' field below MAY contain
any additional information that the manufacturer
thinks might be useful. After sending this message,
the device is not expected to access the bootstrap
server again.";
}
enum informational {
description
"Indicates any additional information not captured by
any of the other notification-type. The 'message'
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field below SHOULD contain any additional information
that the manufacturer thinks might be useful.";
}
}
mandatory true;
description
"The type of notification provided.";
}
leaf message {
type string;
description
"An optional human-readable value.";
}
container ssh-host-keys {
description
"A list of SSH host keys an NMS may use to authenticate
a NETCONF connection to the device with.";
list ssh-host-key {
when "../type = bootstrap-complete" {
description
"SSH host keys are only sent when the notification
type is 'bootstrap-complete'.";
}
description
"An SSH host-key";
leaf format {
type enumeration {
enum ssh-dss { description "ssh-dss"; }
enum ssh-rsa { description "ssh-rsa"; }
}
mandatory true;
description
"The format of the SSH host key.";
}
leaf key-data {
type string;
mandatory true;
description
"The key data for the SSH host key";
}
}
}
container trust-anchors {
description
"A list of trust anchor certificates an NMS may use to
authenticate a NETCONF or RESTCONF connection to the
device with.";
list trust-anchor {
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when "../type = bootstrap-complete" {
description
"Trust anchors are only sent when the notification
type is 'bootstrap-complete'.";
}
description
"A list of trust anchor certificates an NMS may use to
authenticate a NETCONF or RESTCONF connection to the
device with.";
leaf-list protocol {
type enumeration {
enum netconf-ssh { description "netconf-ssh"; }
enum netconf-tls { description "netconf-tls"; }
enum restconf-tls { description "restconf-tls"; }
enum netconf-ch-ssh { description "netconf-ch-ssh"; }
enum netconf-ch-tls { description "netconf-ch-tls"; }
enum restconf-ch-tls { description "restconf-ch-tls"; }
}
min-elements 1;
description
"The protocols that this trust anchor secures.";
}
leaf certificate {
type binary;
mandatory true;
description
"An X.509 v3 certificate structure, as specified by
Section 4 in RFC5280, encoded using ASN.1 distinguished
encoding rules (DER), as specified in ITU-T X.690.";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile.
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
}
}
}
} // end action
} // end device
typedef script {
type binary;
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description
"A device specific script that enables the execution of commands
to perform actions not possible thru configuration alone.
No attempt is made to standardize the contents, running context,
or programming language of the script. The contents of the
script are considered specific to the vendor, product line,
and/or model of the device.
If a script is erroneously provided to a device that does not
support the execution of scripts, the device SHOULD send a
'script-warning' notification message, but otherwise continue
processing the bootstrapping data as if the script had not
been present.
The script returns exit status code '0' on success and non-zero
on error, with accompanying stderr/stdout for logging purposes.
In the case of an error, the exit status code will specify what
the device should do.
If the exit status code is greater than zero, then the device
should assume that the script had a soft error, which the
script believes does not affect manageability. If the device
obtained the bootstrap information from a bootstrap server,
it SHOULD send a 'script-warning' notification message.
If the exit status code is less than zero, the device should
assume the script had a hard error, which the script believes
will affect manageability. In this case, the device SHOULD
send a 'script-error' notification message followed by a
reset that will force a new boot-image install (wiping out
anything the script may have done) and restart the entire
bootstrapping process again.";
}
}
<CODE ENDS>
10. Security Considerations
10.1. Immutable storage for trust anchors
Devices MUST ensure that all their trust anchor certificates,
including those for connecting to bootstrap servers and verifying
ownership vouchers, are protected from external modification.
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It may be necessary to update these certificates over time (e.g., the
manufacturer wants to delegate trust to a new CA). It is therefore
expected that devices MAY update these trust anchors when needed
through a verifiable process, such as a software upgrade using signed
software images.
10.2. Clock Sensitivity
The solution in this document relies on TLS certificates, owner
certificates, and ownership vouchers, all of which require an
accurate clock in order to be processed correctly (e.g., to test
validity dates and revocation status). Implementations MUST ensure
devices have an accurate clock when shipped from manufacturing
facilities, and take steps to prevent clock tampering.
If it is not possible to ensure clock accuracy, it is RECOMMENDED
that implementations disable the aspects of the solution having clock
sensitivity. In particular, such implementations should assume that
TLS certificates, owner certificates, and ownership vouchers are not
revokable, In real-world terms, this means that manufacturers SHOULD
only issue a single ownership voucher for the lifetime of some
devices.
It is important to note that implementations SHOULD NOT rely on NTP
for time, as it is not a secure protocol.
10.3. Blindly authenticating a bootstrap server
This document allows a device to blindly authenticate a bootstrap
server's TLS certificate. It does so to allow for cases where the
redirect information may be obtained in an unsecured manner, which is
desirable to support in some cases.
To compensate for this, this document requires that devices, when
connected to an untrusted bootstrap server, do not send their IDevID
certificate for client authentication, and they do not POST any
progress notifications, and they assert that data downloaded from the
server is signed.
10.4. Entropy loss over time
Section 7.2.7.2 of the IEEE Std 802.1AR-2009 standard says that
IDevID certificate should never expire (i.e. having the notAfter
value 99991231235959Z). Given the long-lived nature of these
certificates, it is paramount to use a strong key length (e.g.,
512-bit ECC).
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10.5. Serial Numbers
This draft suggests using the device's serial number as the unique
identifier in its IDevID certificate. This is because serial numbers
are ubiquitous and prominently contained in invoices and on labels
affixed to devices and their packaging. That said, serial numbers
many times encode revealing information, such as the device's model
number, manufacture date, and/or sequence number. Knowledge of this
information may provide an adversary with details needed to launch an
attack.
10.6. Sequencing Sources of Bootstrapping Data
For devices supporting more than one source for bootstrapping data,
no particular sequencing order has to be observed for security
reasons, as the solution for each source is considered equally
secure. However, from a privacy perspective, it is RECOMMENDED that
devices access local sources before accessing remote sources.
11. IANA Considerations
11.1. The BOOTP Manufacturer Extensions and DHCP Options Registry
The following registrations are in accordance to RFC 2939 [RFC2939]
for "BOOTP Manufacturer Extensions and DHCP Options" registry
maintained at http://www.iana.org/assignments/bootp-dhcp-parameters.
11.1.1. DHCP v4 Option
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Tag: XXX
Name: Zero Touch Information
Returns up to six zero touch bootstrapping artifacts.
Code Len
+-----+-----+----------+------------------+-----------+
| XXX | n | encoding | information-type | signature |
+-----+-----+----------+------------------+-----------+
+-------------------+-------------------+-------------------------+
| owner-certificate | ownership-voucher | certificate-revocations |
+-------------------+-------------------+-------------------------+
+---------------------+
| voucher-revocations |
+---------------------+
Reference: RFC XXXX
11.1.2. DHCP v6 Option
Tag: YYY
Name: Zero Touch Information
Returns up to six zero touch bootstrapping artifacts.
Code Len
+-----+-----+----------+------------------+-----------+
| XXX | n | encoding | information-type | signature |
+-----+-----+----------+------------------+-----------+
+-------------------+-------------------+-------------------------+
| owner-certificate | ownership-voucher | certificate-revocations |
+-------------------+-------------------+-------------------------+
+---------------------+
| voucher-revocations |
+---------------------+
Reference: RFC XXXX
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11.2. The IETF XML Registry
This document registers one URI in the IETF XML registry [RFC3688].
Following the format in [RFC3688], the following registration is
requested:
URI: urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
11.3. The YANG Module Names Registry
This document registers one YANG module in the YANG Module Names
registry [RFC6020]. Following the format defined in [RFC6020], the
the following registration is requested:
name: ietf-zerotouch-bootstrap-server
namespace: urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server
prefix: ztbs
reference: RFC XXXX
12. Other Considerations
Both this document and [draft-ietf-anima-bootstrapping-keyinfra]
define bootstrapping mechanisms. The authors have collaborated on
both solutions and believe that each solution has merit and, in fact,
can work together. That is, it is possible for a device to support
both solutions simultaneously.
13. Acknowledgements
The authors would like to thank for following for lively discussions
on list and in the halls (ordered by last name): David Harrington,
Michael Behringer, Dean Bogdanovic, Martin Bjorklund, Joe Clarke,
Toerless Eckert, Stephen Farrell, Stephen Hanna, Wes Hardaker, Russ
Mundy, Reinaldo Penno, Randy Presuhn, Max Pritikin, Michael
Richardson, Phil Shafer, Juergen Schoenwaelder.
Special thanks goes to Steve Hanna, Russ Mundy, and Wes Hardaker for
brainstorming the original I-D's solution during the IETF 87 meeting
in Berlin.
14. References
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14.1. Normative References
[draft-ietf-netconf-restconf]
Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", draft-ieft-netconf-restconf-10 (work in
progress), 2016, <https://datatracker.ietf.org/html/draft-
ietf-netconf-restconf-10>.
[draft-kwatsen-netconf-voucher]
Watsen, K., Richardson, M., Pritikin, M., and T. Eckert,
"Voucher and Voucher Revocation Profiles for Bootstrapping
Protocols", draft-kwatsen-netconf-voucher-00 (work in
progress), 2016, <https://datatracker.ietf.org/html/draft-
kwatsen-netconf-voucher>.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
November 1987, <http://www.rfc-editor.org/info/rfc1035>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC2315] Kaliski, B., "PKCS #7: Cryptographic Message Syntax
Version 1.5", RFC 2315, DOI 10.17487/RFC2315, March 1998,
<http://www.rfc-editor.org/info/rfc2315>.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<http://www.rfc-editor.org/info/rfc5280>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<http://www.rfc-editor.org/info/rfc6020>.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
2011, <http://www.rfc-editor.org/info/rfc6125>.
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[RFC6234] Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms
(SHA and SHA-based HMAC and HKDF)", RFC 6234,
DOI 10.17487/RFC6234, May 2011,
<http://www.rfc-editor.org/info/rfc6234>.
[RFC6762] Cheshire, S. and M. Krochmal, "Multicast DNS", RFC 6762,
DOI 10.17487/RFC6762, February 2013,
<http://www.rfc-editor.org/info/rfc6762>.
[RFC6763] Cheshire, S. and M. Krochmal, "DNS-Based Service
Discovery", RFC 6763, DOI 10.17487/RFC6763, February 2013,
<http://www.rfc-editor.org/info/rfc6763>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<http://www.rfc-editor.org/info/rfc6991>.
[RFC7468] Josefsson, S. and S. Leonard, "Textual Encodings of PKIX,
PKCS, and CMS Structures", RFC 7468, DOI 10.17487/RFC7468,
April 2015, <http://www.rfc-editor.org/info/rfc7468>.
[Std-802.1AR-2009]
IEEE SA-Standards Board, "IEEE Standard for Local and
metropolitan area networks - Secure Device Identity",
December 2009, <http://standards.ieee.org/findstds/
standard/802.1AR-2009.html>.
14.2. Informative References
[draft-ietf-anima-bootstrapping-keyinfra]
Pritikin, M., Behringer, M., and S. Bjarnason,
"Bootstrapping Key Infrastructures", draft-ietf-anima-
bootstrapping-keyinfra-03 (work in progress), 2016,
<https://datatracker.ietf.org/html/draft-ietf-anima-
bootstrapping-keyinfra>.
[draft-ietf-netconf-call-home]
Watsen, K., "NETCONF Call Home (work in progress)", draft-
ieft-netconf-restconf-10 (work in progress), December
2015, <https://datatracker.ietf.org/html/draft-ietf-
netconf-call-home-17>.
[draft-ietf-netconf-server-model]
Watsen, K., "NETCONF Server Model (work in progress)",
draft-ieft-netconf-server-model-09 (work in progress),
March 2016, <https://datatracker.ietf.org/html/draft-ietf-
netconf-call-home-17>.
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[RFC2939] Droms, R., "Procedures and IANA Guidelines for Definition
of New DHCP Options and Message Types", BCP 43, RFC 2939,
DOI 10.17487/RFC2939, September 2000,
<http://www.rfc-editor.org/info/rfc2939>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<http://www.rfc-editor.org/info/rfc3688>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<http://www.rfc-editor.org/info/rfc6241>.
[RFC6698] Hoffman, P. and J. Schlyter, "The DNS-Based Authentication
of Named Entities (DANE) Transport Layer Security (TLS)
Protocol: TLSA", RFC 6698, DOI 10.17487/RFC6698, August
2012, <http://www.rfc-editor.org/info/rfc6698>.
[RFC7317] Bierman, A. and M. Bjorklund, "A YANG Data Model for
System Management", RFC 7317, DOI 10.17487/RFC7317, August
2014, <http://www.rfc-editor.org/info/rfc7317>.
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Appendix A. API Examples
This section presents some examples illustrating device interactions
with a bootstrap server to access Redirect and Bootstrap information,
both unsigned and signed, as well as to send a progress notification.
These examples show the bootstrap information containing
configuration from the YANG modules in [RFC7317] and
[draft-ietf-netconf-server-model].
A.1. Unsigned Redirect Information
The following example illustrates a device using the API to fetch its
bootstrapping data. In this example, the device receives unsigned
redirect information. This example is representative of a response a
trusted redirect server might return.
REQUEST
-------
['\' line wrapping added for formatting only]
GET https://example.com/restconf/data/ietf-zerotouch-bootstrap-server:\
device=123456 HTTP/1.1
HOST: example.com
Accept: application/yang.data+xml
RESPONSE
--------
HTTP/1.1 200 OK
Date: Sat, 31 Oct 2015 17:02:40 GMT
Server: example-server
Content-Type: application/yang.data+xml
<!-- '\' line wrapping added for formatting purposes only -->
<device
xmlns="urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server">
<unique-id>123456789</unique-id>
<redirect-information>
<bootstrap-server>
<address>phs1.example.com</address>
<port>8443</port>
<trust-anchor>
WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM\
lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk\
zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot\
NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd\
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VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER\
V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF\
NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC\
Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN\
WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW\
QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ\
MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ\
25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2\
RJSUJQFRStS0Cg==
</trust-anchor>
</bootstrap-server>
<bootstrap-server>
<address>phs2.example.com</address>
<port>8443</port>
<trust-anchor>
WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM\
lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk\
zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot\
NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd\
VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER\
V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF\
NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC\
Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN\
WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW\
QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ\
MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ\
25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2\
RJSUJQFRStS0Cg==
</trust-anchor>
</bootstrap-server>
</redirect-information>
</device>
A.2. Signed Redirect Information
The following example illustrates a device using the API to fetch its
bootstrapping data. In this example, the device receives signed
redirect information. This example is representative of a response
that redirect server might return if concerned the device might not
be able to authenticate its TLS certificate.
REQUEST
-------
['\' line wrapping added for formatting only]
GET https://example.com/restconf/data/ietf-zerotouch-bootstrap-server:\
device=123456 HTTP/1.1
HOST: example.com
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Accept: application/yang.data+xml
RESPONSE
--------
HTTP/1.1 200 OK
Date: Sat, 31 Oct 2015 17:02:40 GMT
Server: example-server
Content-Type: application/yang.data+xml
<!-- '\' line wrapping added for formatting purposes only -->
<device
xmlns="urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server">
<unique-id>123456789</unique-id>
<redirect-information>
<bootstrap-server>
<address>phs1.example.com</address>
<port>8443</port>
<trust-anchor>
WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM\
lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk\
zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot\
NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd\
VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER\
V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF\
NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC\
Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN\
WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW\
QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ\
MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ\
25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2\
RJSUJQFRStS0Cg==
</trust-anchor>
</bootstrap-server>
<bootstrap-server>
<address>phs2.example.com</address>
<port>8443</port>
<trust-anchor>
WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM\
lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk\
zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot\
NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd\
VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER\
V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF\
NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC\
Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN\
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WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW\
QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ\
MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ\
25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2\
RJSUJQFRStS0Cg==
</trust-anchor>
</bootstrap-server>
</redirect-information>
<signature>
RDEuRiZNRNLeJpgN9YWkXLAZX2rASwy041EMmZ6KAkWUd3ZmXucfoLpdRemfuPii\
QGp1bmlwZXIuY29tMB4XDTE0MDIyNzE0MTM1MloXDTE1MDIyNzE0MTM1MlowMDET\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
NTOufhQsD2t4TYpEkzLEiZqSswdBOaPxPcJLQNW8Bw2xN+A9GX=
</signature>
<ownership-voucher>
ChQQSnVuaXBlcl9OZXR3b3JrczEdMBsGA1UECxQUQ2VydGlmaWNhdGVfSXNzdWFu\
Y2UxGTAXBgNVBAMUEFRQTV9UcnVzdF9BbmNob3IxHTAbBgkqhkiG9w0BCQEWDmNh\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
yh/JaftWYf7m3KBzOdg2MIHfBgNVHSMEgdcwgdSAFDSljCNmTN5b+CDujJLlyDal\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
MBAGA1UEBxMJU3Vubnl2YWxlMRkwFwYDVQQKFBBKdW5pcGVyX05ldHdvcmtzMR0w\
GwYDVQQLFBRDZXJ0aWZpY2F0ZV9Jc3N1YW5jZTEZMBcGA1UEAxQQVFBNX1RydXN0\
X0FuY2hvcjEdMBsGCSqGSIb3DQEJARYOY2FAanVuaXBlci5jb22CCQDUbsEdTn5v\
MjAO
</ownership-voucher>
<owner-certificate>
MIIExTCCA62gAwIBAgIBATANBgkqhkiG9w0BAQsFADCBqjELMAkGA1UEBhMCVVMx\
EzARBgNVBAgTCkNhbGlmb3JuaWExEjAQBgNVBAcTCVN1bm55dmFsZTEZMBcGA1UE\
ChQQSnVuaXBlcl9OZXR3b3JrczEdMBsGA1UECxQUQ2VydGlmaWNhdGVfSXNzdWFu\
Y2UxGTAXBgNVBAMUEFRQTV9UcnVzdF9BbmNob3IxHTAbBgkqhkiG9w0BCQEWDmNh\
QGp1bmlwZXIuY29tMB4XDTE0MDIyNzE0MTM1MloXDTE1MDIyNzE0MTM1MlowMDET\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
RDEuRiZNRNLeJpgN9YWkXLAZX2rASwy041EMmZ6KAkWUd3ZmXucfoLpdRemfuPii\
ap1DgmS3IaYl/s4OOF8yzcYJprm8O7NyZp+Y9H1U/7Qfp97/KbqwCgkHSzOlnt0X\
KQTpIM/rNrbrkuTmalezFoFS7mrxLXJAsfP1guVcD7sLCyjvegL8pRCCrU9xyKLF\
8u/Qz4s0x0uzcGYh0sd3iWj21+AtigSLdMD76/j/VzftQL8B1yp3vc1EZiowOwq4\
KmORbiKU2GTGZkaCgCjmrWpvrYWLoXv/sf2nPLyK6YjiWsslOJtRO+KzRbs2B18C\
AwEAAaOCAW0wggFpMBIGA1UdEwEB/wQIMAYBAf8CAQAwHQYDVR0OBBYEFHppoyXF\
yh/JaftWYf7m3KBzOdg2MIHfBgNVHSMEgdcwgdSAFDSljCNmTN5b+CDujJLlyDal\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
MBAGA1UEBxMJU3Vubnl2YWxlMRkwFwYDVQQKFBBKdW5pcGVyX05ldHdvcmtzMR0w\
GwYDVQQLFBRDZXJ0aWZpY2F0ZV9Jc3N1YW5jZTEZMBcGA1UEAxQQVFBNX1RydXN0\
X0FuY2hvcjEdMBsGCSqGSIb3DQEJARYOY2FAanVuaXBlci5jb22CCQDUbsEdTn5v\
MjAOBgNVHQ8BAf8EBAMCAgQwQgYDVR0fBDswOTA3oDWgM4YxaHR0cDovL2NybC5q\
dW5pcGVyLm5ldD9jYT1KdW5pcGVyX1RydXN0X0FuY2hvcl9DQTANBgkqhkiG9w0B\
AQsFAAOCAQEAOuD7EBilqQcT3t2C4AXta1gGNNwdldLLw0jtk4BMiA9l//DZfskB\
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2AaJtiseLTXsMF6MQwDs1YKkiXKLu7gBZDlJ6NiDwy1UnXhi2BDG+MYXQrc6p76K\
z3bsVwZlaJQCdF5sbggc1MyrsOu9QirnRZkIv3R8ndJH5K792ztLquulAcMfnK1Y\
NTOufhQsD2t4TYpEkzLEiZqSswdBOaPxPcJLQNW8Bw2xN+A9GX7WJzEbT/G7MUfo\
Sb+U2PVsQTDWEzUjVnG7vNWYxirnAOZ0OXEWWYxHUJntx6DsbXYuX7D1PkkNr7ir\
96DpOPtX7h8pxxGSDPBXIyvg02aFMphstQ==
</owner-certificate>
<voucher-revocation>
QGp1bmlwZXIuY29tMB4XDTE0MDIyNzE0MTM1MloXDTE1MDIyNzE0MTM1MlowMDET\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
RDEuRiZNRNLeJpgN9YWkXLAZX2rASwy041EMmZ6KAkWUd3ZmXucfoLpdRemfuPii\
KQTpIM/rNrbrkuTmalezFoFS7mrxLXJAsfP1guVcD7sLCyjvegL8pRCCrU9xyKLF\
8u/Qz4s0x0uzcGYh0sd3iWj21+AtigSLdMD76/j/VzftQL8B1yp3vc1EZiowOwq4\
AwEAAaOCAW0wggFpMBIGA1UdEwEB/wQIMAYBAf8CAQAwHQYDVR0OBBYEFHppoyXF\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
NTOufhQsD2t4TYpEkzLEiZqSswdBOaPxPcJLQNW8Bw2xN+A9GX=
</voucher-revocation>
<certificate-revocation>
Y2UxGTAXBgNVBAMUEFRQTV9UcnVzdF9BbmNob3IxHTAbBgkqhkiG9w0BCQEWDmNh\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
yh/JaftWYf7m3KBzOdg2MIHfBgNVHSMEgdcwgdSAFDSljCNmTN5b+CDujJLlyDal\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
MBAGA1UEBxMJU3Vubnl2YWxlMRkwFwYDVQQKFBBKdW5pcGVyX05ldHdvcmtzMR0w\
GwYDVQQLFBRDZXJ0aWZpY2F0ZV9Jc3N1YW5jZTEZMBcGA1UEAxQQVFBNX1RydXN0\
X0FuY2hvcjEdMBsGCSqGSIb3DQEJARYOY2FAanVuaXBlci5jb22CCQDUbsEdTn5v\
MjAO==
</certificate-revocation>
</device>
A.3. Unsigned Bootstrap Information
The following example illustrates a device using the API to fetch its
bootstrapping data. In this example, the device receives unsigned
bootstrapping information. This example is representative of a
response a locally deployed bootstrap server might return.
REQUEST
-------
['\' line wrapping added for formatting only]
GET https://example.com/restconf/data/ietf-zerotouch-bootstrap-server:\
device=123456 HTTP/1.1
HOST: example.com
Accept: application/yang.data+xml
RESPONSE
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--------
HTTP/1.1 200 OK
Date: Sat, 31 Oct 2015 17:02:40 GMT
Server: example-server
Content-Type: application/yang.data+xml
<!-- '\' line wrapping added for formatting purposes only -->
<device
xmlns="urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server">
<unique-id>123456789</unique-id>
<bootstrap-information>
<boot-image>
<name>
boot-image-v3.2R1.6.img
</name>
<md5>
SomeMD5String
</md5>
<sha1>
SomeSha1String
</sha1>
<uri>
ftp://ftp.example.com/path/to/file
</uri>
</boot-image>
<configuration-handling>merge</configuration-handling>
<configuration>
<!-- from ietf-system.yang -->
<system xmlns="urn:ietf:params:xml:ns:yang:ietf-system">
<authentication>
<user>
<name>admin</name>
<authorized-key>
<name>admin's rsa ssh host-key</name>
<algorithm>ssh-rsa</algorithm>
<key-data>AAAAB3NzaC1yc2EAAAADAQABAAABAQDeJMV8zrtsi8CgEsR\
jCzfve2m6zD3awSBPrh7ICggLQvHVbPL89eHLuecStKL3HrEgXaI/O2Mw\
E1lG9YxLzeS5p2ngzK61vikUSqfMukeBohFTrDZ8bUtrF+HMLlTRnoCVc\
WAw1lOr9IDGDAuww6G45gLcHalHMmBtQxKnZdzU9kx/fL3ZS5G76Fy6sA\
vg7SLqQFPjXXft2CAhin8xwYRZy6r/2N9PMJ2Dnepvq4H2DKqBIe340jW\
EIuA7LvEJYql4unq4Iog+/+CiumTkmQIWRgIoj4FCzYkO9NvRE6fOSLLf\
gakWVOZZgQ8929uWjCWlGlqn2mPibp2Go1</key-data>
</authorized-key>
</user>
</authentication>
</system>
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<!-- from ietf-netconf-server.yang -->
<netconf-server
xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server">
<call-home>
<application>
<name>config-mgr</name>
<ssh>
<endpoints>
<endpoint>
<name>east-data-center</name>
<address>11.22.33.44</address>
</endpoint>
<endpoint>
<name>west-data-center</name>
<address>55.66.77.88</address>
</endpoint>
</endpoints>
<host-keys>
<host-key>my-call-home-x509-key</host-key>
</host-keys>
</ssh>
</application>
</call-home>
</netconf-server>
</configuration>
</bootstrap-information>
</device>
A.4. Signed Bootstrap Information
The following example illustrates a device using the API to fetch its
bootstrapping data. In this example, the device receives signed
bootstrap information. This example is representative of a response
that bootstrap server might return if concerned the device might not
be able to authenticate its TLS certificate.
REQUEST
-------
['\' line wrapping added for formatting only]
GET https://example.com/restconf/data/ietf-zerotouch-bootstrap-server:\
device=123456 HTTP/1.1
HOST: example.com
Accept: application/yang.data+xml
RESPONSE
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--------
HTTP/1.1 200 OK
Date: Sat, 31 Oct 2015 17:02:40 GMT
Server: example-server
Content-Type: application/yang.data+xml
<!-- '\' line wrapping added for formatting purposes only -->
<device
xmlns="urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server">
<unique-id>123456789</unique-id>
<bootstrap-information>
<boot-image>
<name>
boot-image-v3.2R1.6.img
</name>
<md5>
SomeMD5String
</md5>
<sha1>
SomeSha1String
</sha1>
<uri>
/path/to/on/same/bootserver
</uri>
</boot-image>
<configuration>
<!-- from ietf-system.yang -->
<system xmlns="urn:ietf:params:xml:ns:yang:ietf-system">
<authentication>
<user>
<name>admin</name>
<authorized-key>
<name>admin's rsa ssh host-key</name>
<algorithm>ssh-rsa</algorithm>
<key-data>AAAAB3NzaC1yc2EAAAADAQABAAABAQDeJMV8zrtsi8CgEsR\
jCzfve2m6zD3awSBPrh7ICggLQvHVbPL89eHLuecStKL3HrEgXaI/O2Mw\
E1lG9YxLzeS5p2ngzK61vikUSqfMukeBohFTrDZ8bUtrF+HMLlTRnoCVc\
WAw1lOr9IDGDAuww6G45gLcHalHMmBtQxKnZdzU9kx/fL3ZS5G76Fy6sA\
vg7SLqQFPjXXft2CAhin8xwYRZy6r/2N9PMJ2Dnepvq4H2DKqBIe340jW\
EIuA7LvEJYql4unq4Iog+/+CiumTkmQIWRgIoj4FCzYkO9NvRE6fOSLLf\
gakWVOZZgQ8929uWjCWlGlqn2mPibp2Go1</key-data>
</authorized-key>
</user>
</authentication>
</system>
<!-- from ietf-netconf-server.yang -->
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<netconf-server
xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-server">
<call-home>
<application>
<name>config-mgr</name>
<ssh>
<endpoints>
<endpoint>
<name>east-data-center</name>
<address>11.22.33.44</address>
</endpoint>
<endpoint>
<name>west-data-center</name>
<address>55.66.77.88</address>
</endpoint>
</endpoints>
<host-keys>
<host-key>my-call-home-x509-key</host-key>
</host-keys>
</ssh>
</application>
</call-home>
</netconf-server>
</configuration>
</bootstrap-information>
<signature>
RDEuRiZNRNLeJpgN9YWkXLAZX2rASwy041EMmZ6KAkWUd3ZmXucfoLpdRemfuPii\
QGp1bmlwZXIuY29tMB4XDTE0MDIyNzE0MTM1MloXDTE1MDIyNzE0MTM1MlowMDET\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
NTOufhQsD2t4TYpEkzLEiZqSswdBOaPxPcJLQNW8Bw2xN+A9GX=
</signature>
<ownership-voucher>
ChQQSnVuaXBlcl9OZXR3b3JrczEdMBsGA1UECxQUQ2VydGlmaWNhdGVfSXNzdWFu\
Y2UxGTAXBgNVBAMUEFRQTV9UcnVzdF9BbmNob3IxHTAbBgkqhkiG9w0BCQEWDmNh\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
yh/JaftWYf7m3KBzOdg2MIHfBgNVHSMEgdcwgdSAFDSljCNmTN5b+CDujJLlyDal\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
MBAGA1UEBxMJU3Vubnl2YWxlMRkwFwYDVQQKFBBKdW5pcGVyX05ldHdvcmtzMR0w\
GwYDVQQLFBRDZXJ0aWZpY2F0ZV9Jc3N1YW5jZTEZMBcGA1UEAxQQVFBNX1RydXN0\
X0FuY2hvcjEdMBsGCSqGSIb3DQEJARYOY2FAanVuaXBlci5jb22CCQDUbsEdTn5v\
MjAO
</ownership-voucher>
<owner-certificate>
MIIExTCCA62gAwIBAgIBATANBgkqhkiG9w0BAQsFADCBqjELMAkGA1UEBhMCVVMx\
EzARBgNVBAgTCkNhbGlmb3JuaWExEjAQBgNVBAcTCVN1bm55dmFsZTEZMBcGA1UE\
ChQQSnVuaXBlcl9OZXR3b3JrczEdMBsGA1UECxQUQ2VydGlmaWNhdGVfSXNzdWFu\
Y2UxGTAXBgNVBAMUEFRQTV9UcnVzdF9BbmNob3IxHTAbBgkqhkiG9w0BCQEWDmNh\
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QGp1bmlwZXIuY29tMB4XDTE0MDIyNzE0MTM1MloXDTE1MDIyNzE0MTM1MlowMDET\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
RDEuRiZNRNLeJpgN9YWkXLAZX2rASwy041EMmZ6KAkWUd3ZmXucfoLpdRemfuPii\
ap1DgmS3IaYl/s4OOF8yzcYJprm8O7NyZp+Y9H1U/7Qfp97/KbqwCgkHSzOlnt0X\
KQTpIM/rNrbrkuTmalezFoFS7mrxLXJAsfP1guVcD7sLCyjvegL8pRCCrU9xyKLF\
8u/Qz4s0x0uzcGYh0sd3iWj21+AtigSLdMD76/j/VzftQL8B1yp3vc1EZiowOwq4\
KmORbiKU2GTGZkaCgCjmrWpvrYWLoXv/sf2nPLyK6YjiWsslOJtRO+KzRbs2B18C\
AwEAAaOCAW0wggFpMBIGA1UdEwEB/wQIMAYBAf8CAQAwHQYDVR0OBBYEFHppoyXF\
yh/JaftWYf7m3KBzOdg2MIHfBgNVHSMEgdcwgdSAFDSljCNmTN5b+CDujJLlyDal\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
MBAGA1UEBxMJU3Vubnl2YWxlMRkwFwYDVQQKFBBKdW5pcGVyX05ldHdvcmtzMR0w\
GwYDVQQLFBRDZXJ0aWZpY2F0ZV9Jc3N1YW5jZTEZMBcGA1UEAxQQVFBNX1RydXN0\
X0FuY2hvcjEdMBsGCSqGSIb3DQEJARYOY2FAanVuaXBlci5jb22CCQDUbsEdTn5v\
MjAOBgNVHQ8BAf8EBAMCAgQwQgYDVR0fBDswOTA3oDWgM4YxaHR0cDovL2NybC5q\
dW5pcGVyLm5ldD9jYT1KdW5pcGVyX1RydXN0X0FuY2hvcl9DQTANBgkqhkiG9w0B\
AQsFAAOCAQEAOuD7EBilqQcT3t2C4AXta1gGNNwdldLLw0jtk4BMiA9l//DZfskB\
2AaJtiseLTXsMF6MQwDs1YKkiXKLu7gBZDlJ6NiDwy1UnXhi2BDG+MYXQrc6p76K\
z3bsVwZlaJQCdF5sbggc1MyrsOu9QirnRZkIv3R8ndJH5K792ztLquulAcMfnK1Y\
NTOufhQsD2t4TYpEkzLEiZqSswdBOaPxPcJLQNW8Bw2xN+A9GX7WJzEbT/G7MUfo\
Sb+U2PVsQTDWEzUjVnG7vNWYxirnAOZ0OXEWWYxHUJntx6DsbXYuX7D1PkkNr7ir\
96DpOPtX7h8pxxGSDPBXIyvg02aFMphstQ==
</owner-certificate>
<voucher-revocation>
QGp1bmlwZXIuY29tMB4XDTE0MDIyNzE0MTM1MloXDTE1MDIyNzE0MTM1MlowMDET\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
RDEuRiZNRNLeJpgN9YWkXLAZX2rASwy041EMmZ6KAkWUd3ZmXucfoLpdRemfuPii\
KQTpIM/rNrbrkuTmalezFoFS7mrxLXJAsfP1guVcD7sLCyjvegL8pRCCrU9xyKLF\
8u/Qz4s0x0uzcGYh0sd3iWj21+AtigSLdMD76/j/VzftQL8B1yp3vc1EZiowOwq4\
AwEAAaOCAW0wggFpMBIGA1UdEwEB/wQIMAYBAf8CAQAwHQYDVR0OBBYEFHppoyXF\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
NTOufhQsD2t4TYpEkzLEiZqSswdBOaPxPcJLQNW8Bw2xN+A9GX=
</voucher-revocation>
<certificate-revocation>
Y2UxGTAXBgNVBAMUEFRQTV9UcnVzdF9BbmNob3IxHTAbBgkqhkiG9w0BCQEWDmNh\
MBEGA1UEChQKVFBNX1ZlbmRvcjEZMBcGA1UEAxQQSnVuaXBlcl9YWFhYWF9DQTCC\
ASIwDQYJKoZIhvcNAQEBBQADggEPADCCAQoCggEBANL5Mk5qFsVuqo+JmXWLmFxI\
yh/JaftWYf7m3KBzOdg2MIHfBgNVHSMEgdcwgdSAFDSljCNmTN5b+CDujJLlyDal\
WFPaoYGwpIGtMIGqMQswCQYDVQQGEwJVUzETMBEGA1UECBMKQ2FsaWZvcm5pYTES\
MBAGA1UEBxMJU3Vubnl2YWxlMRkwFwYDVQQKFBBKdW5pcGVyX05ldHdvcmtzMR0w\
GwYDVQQLFBRDZXJ0aWZpY2F0ZV9Jc3N1YW5jZTEZMBcGA1UEAxQQVFBNX1RydXN0\
X0FuY2hvcjEdMBsGCSqGSIb3DQEJARYOY2FAanVuaXBlci5jb22CCQDUbsEdTn5v\
MjAO==
</certificate-revocation>
</device>
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A.5. Progress Notifications
The following example illustrates a device using the API to post a
notification to a trusted bootstrap server. Illustrated below is the
'bootstrap-complete' message, but the device may send other
notifications to the server while bootstrapping (e.g., to provide
status updates).
The bootstrap server MUST NOT process a notification from a device
without first authenticating the device. This is in contrast to when
a device is fetching data from the server, a read-only operation, in
which case device authentication is not strictly required (e.g., when
sending signed information).
In this example, the device sends a notification indicating that it
has completed bootstrapping off the data provided by the server.
This example illustrates the device sending both its SSH host keys
and TLS server certificate to the bootstrap server, which the
bootstrap server may, for example, pass to an NMS, as discussed in
Section 7.3.
Note that devices that are able to present an IDevID certificate
[Std-802.1AR-2009], when establishing SSH or TLS connections, do not
need to include its DevID certificate in the bootstrap-complete
message. It is unnecessary to send the DevID certificate in this
case because the IDevID certificate does not need to be pinned by an
NMS in order to be trusted.
REQUEST
-------
['\' line wrapping added for formatting only]
POST https://example.com/restconf/data/ietf-zerotouch-bootstrap-server:\
device=123456/notification HTTP/1.1
HOST: example.com
Content-Type: application/yang.data+xml
<!-- '\' line wrapping added for formatting purposes only -->
<input
xmlns="urn:ietf:params:xml:ns:yang:ietf-zerotouch-bootstrap-server">
<notification-type>bootstrap-complete</notification-type>
<message>example message</message>
<ssh-host-keys>
<ssh-host-key>
<format>ssh-rsa</format>
<key-data>
AAAAB3NzaC1yc2EAAAADAQABAAABAQDeJMV8zrtsi8CgEsRCjCzfve2m6\
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zD3awSBPrh7ICggLQvHVbPL89eHLuecStKL3HrEgXaI/O2MwjE1lG9YxL\
zeS5p2ngzK61vikUSqfMukeBohFTrDZ8bUtrF+HMLlTRnoCVcCWAw1lOr\
9IDGDAuww6G45gLcHalHMmBtQxKnZdzU9kx/fL3ZS5G76Fy6sA5vg7SLq\
QFPjXXft2CAhin8xwYRZy6r/2N9PMJ2Dnepvq4H2DKqBIe340jWqEIuA7\
LvEJYql4unq4Iog+/+CiumTkmQIWRgIoj4FCzYkO9NvRE6fOSLLf6gakW\
VOZZgQ8929uWjCWlGlqn2mPibp2Go1
</key-data>
</ssh-host-key>
<ssh-host-key>
<format>ssh-dsa</format>
<key-data>
zD3awSBPrh7ICggLQvHVbPL89eHLuecStKL3HrEgXaI/O2MwjE1lG9YxL\
zeS5p2ngzK61vikUSqfMukeBohFTrDZ8bUtrF+HMLlTRnoCVcCWAw1lOr\
9IDGDAuww6G45gLcHalHMmBtQxKnZdzU9kx/fL3ZS5G76Fy6sA5vg7SLq\
AAAAB3NzaC1yc2EAAAADAQABAAABAQDeJMV8zrtsi8CgEsRCjCzfve2m6\
QFPjXXft2CAhin8xwYRZy6r/2N9PMJ2Dnepvq4H2DKqBIe340jWqEIuA7\
LvEJYql4unq4Iog+/+CiumTkmQIWRgIoj4FCzYkO9NvRE6fOSLLf6gakW\
VOZZgQ8929uWjCWlGlqn2mPibp2Go1
</key-data>
</ssh-host-key>
</ssh-host-keys>
<trust-anchors>
<trust-anchor>
<protocol>netconf-ssh</protocol>
<protocol>netconf-tls</protocol>
<protocol>restconf-tls</protocol>
<protocol>netconf-ch-ssh</protocol>
<protocol>netconf-ch-tls</protocol>
<protocol>restconf-ch-tls</protocol>
<certificate>
WmdsK2gyTTg3QmtGMjhWbW1CdFFVaWc3OEgrRkYyRTFwdSt4ZVRJbVFFM\
lLQllsdWpOcjFTMnRLR05EMUc2OVJpK2FWNGw2NTdZNCtadVJMZgpRYjk\
zSFNwSDdwVXBCYnA4dmtNanFtZjJma3RqZHBxeFppUUtTbndWZTF2Zwot\
NGcEk3UE90cnNFVjRwTUNBd0VBQWFPQ0FSSXdnZ0VPCk1CMEdBMVVkRGd\
VEJiZ0JTWEdlbUEKMnhpRHVOTVkvVHFLNWd4cFJBZ1ZOYUU0cERZd05ER\
V6QVJCZ05WQkFNVENrTlNUQ0JKYzNOMVpYS0NDUUNVRHBNSll6UG8zREF\
NQmdOVkhSTUJBZjhFCkFqQUFNQTRHQTFVZER3RUIvd1FFQXdJSGdEQnBC\
Z05WSFI4RVlqQmdNRjZnSXFBZ2hoNW9kSFJ3T2k4dlpYaGgKYlhCc1pTN\
WpiMjB2WlhoaGJYQnNaUzVqY215aU9LUTJNRFF4Q3pBSkJnTlZCQVlUQW\
QmdOVkJBWVRBbFZUTVJBd0RnWURWUVFLRXdkbAplR0Z0Y0d4bE1RNHdEQ\
MkF6a3hqUDlVQWtHR0dvS1U1eUc1SVR0Wm0vK3B0R2FieXVDMjBRd2kvZ\
25PZnpZNEhONApXY0pTaUpZK2xtYWs3RTRORUZXZS9RdGp4NUlXZmdvN2\
RJSUJQFRStS0Cg==
</certificate>
</trust-anchor>
</trust-anchors>
</input>
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RESPONSE
--------
HTTP/1.1 204 No Content
Date: Sat, 31 Oct 2015 17:02:40 GMT
Server: example-server
Appendix B. Artifact Examples
This section presents examples for how the 'information type'
artifact (Section 4.1) can be encoded into a document that can be
distributed outside the bootstrap server's RESETCONF API. The
encoding for these artifacts is the same as if an HTTP GET request
had been sent to the RESTCONF URL for the specific resource.
These examples show the bootstrap information containing
configuration from the YANG modules in [RFC7317] and
[draft-ietf-netconf-server-model].
Only examples for information type artifact are provided as the other
five artifacts in Section 4 have their own encodings.
B.1. Redirect Information
The following example illustrates how redirect information can be
encoded into an artifact.
INSERT _TEXT_FROM_FILE(refs/ex-file-redirect-information.xml)
B.2. Bootstrap Information
The following example illustrates how bootstrap information can be
encoded into an artifact.
INSERT _TEXT_FROM_FILE(refs/ex-file-bootstrap-information.xml)
Appendix C. Change Log
C.1. ID to 00
o Major structural update; the essence is the same. Most every
section was rewritten to some degree.
o Added a Use Cases section
o Added diagrams for "Actors and Roles" and "NMS Precondition"
sections, and greatly improved the "Device Boot Sequence" diagram
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o Removed support for physical presence or any ability for
configlets to not be signed.
o Defined the Zero Touch Information DHCP option
o Added an ability for devices to also download images from
configuration servers
o Added an ability for configlets to be encrypted
o Now configuration servers only have to support HTTP/S - no other
schemes possible
C.2. 00 to 01
o Added boot-image and validate-owner annotations to the "Actors and
Roles" diagram.
o Fixed 2nd paragraph in section 7.1 to reflect current use of
anyxml.
o Added encrypted and signed-encrypted examples
o Replaced YANG module with XSD schema
o Added IANA request for the Zero Touch Information DHCP Option
o Added IANA request for media types for boot-image and
configuration
C.3. 01 to 02
o Replaced the need for a configuration signer with the ability for
each NMS to be able to sign its own configurations, using
manufacturer signed ownership vouchers and owner certificates.
o Renamed configuration server to bootstrap server, a more
representative name given the information devices download from
it.
o Replaced the concept of a configlet by defining a southbound
interface for the bootstrap server using YANG.
o Removed the IANA request for the boot-image and configuration
media types
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C.4. 02 to 03
o Minor update, mostly just to add an Editor's Note to show how this
draft might integrate with the draft-pritikin-anima-bootstrapping-
keyinfra.
C.5. 03 to 04
o Major update formally introducing unsigned data and support for
Internet-based redirect servers.
o Added many terms to Terminology section.
o Added all new "Guiding Principles" section.
o Added all new "Sources for Bootstrapping Data" section.
o Rewrote the "Interactions" section and renamed it "Workflow
Overview".
C.6. 04 to 05
o Semi-major update, refactoring the document into more logical
parts
o Created new section for information types
o Added support for DNS servers
o Now allows provisional TLS connections
o Bootstrapping data now supports scripts
o Device Details section overhauled
o Security Considerations expanded
o Filled in enumerations for notification types
C.7. 05 to 06
o Minor update
o Added many Normative and Informative references.
o Added new section Other Considerations.
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C.8. 06 to 07
o Minor update
o Added an Editorial Note section for RFC Editor.
o Updated the IANA Considerations section.
C.9. 07 to 08
o Minor update
o Updated to reflect review from Michael Richardson.
C.10. 08 to 09
o Added in missing "Signature" artifact example.
o Added recommendation for manufacturers to use interoperable
formats and file naming conventions for removable storage devices.
o Added configuration-handling leaf to guide if config should be
merged, replaced, or processed like an edit-config/yang-patch
document.
o Added a pre-configuration script, in addition to the post-
configuration script from -05 (issue #15).
C.11. 09 to 10
o Factored ownership vocher and voucher revocation to a separate
document: draft-kwatsen-netconf-voucher. (issue #11)
o Removed <configuration-handling> options 'edit-config' and yang-
patch'. (issue #12)
o Defined how a signature over signed-data returned from a bootstrap
server is processed. (issue #13)
o Added recommendation for removable storage devices to use open/
standard file systems when possible. (issue #14)
o Replaced notifications "script-[warning/error]" with "[pre/post]-
script-[warning/error]". (goes with issue #15)
o switched owner-certificate to be encoded using the pkcs#7 format.
(issue #16)
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o Replaced md5/sha1 with sha256 inside a choice statement, for
future extensibility. (issue #17)
o A ton of editorial changes, as I went thru the entire draft with a
fine-toothed comb.
Authors' Addresses
Kent Watsen
Juniper Networks
EMail: kwatsen@juniper.net
Mikael Abrahamsson
T-Systems
EMail: "mikael.abrahamsson@t-systems.se
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