NETCONF Working Group K. Watsen
Internet-Draft Juniper Networks
Intended status: Standards Track October 30, 2017
Expires: May 3, 2018
YANG Data Model for a "Keystore" Mechanism
draft-ietf-netconf-keystore-04
Abstract
This document defines a YANG module called a "keystore", containing
pinned certificates and pinned SSH host-keys. The module also
defines a grouping for configuring public key pairs and a grouping
for configuring certificates. The module also defines a notification
that a system can use when one of its configured certificates is
about to expire.
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. No other RFC
Editor instructions are specified elsewhere in this document.
Artwork in this document contains shorthand references to drafts in
progress. Please apply the following replacements:
o "VVVV" --> the assigned RFC value for this draft
Artwork in this document contains placeholder values for the date of
publication of this draft. Please apply the following replacement:
o "2017-10-30" --> the publication date of this draft
The following Appendix section is to be removed prior to publication:
o Appendix A. Change Log
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on May 3, 2018.
Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
2. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Example Usage . . . . . . . . . . . . . . . . . . . . . . . . 5
4. YANG Module . . . . . . . . . . . . . . . . . . . . . . . . . 10
5. Security Considerations . . . . . . . . . . . . . . . . . . . 21
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22
6.1. The IETF XML Registry . . . . . . . . . . . . . . . . . . 22
6.2. The YANG Module Names Registry . . . . . . . . . . . . . 22
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 23
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 23
8.1. Normative References . . . . . . . . . . . . . . . . . . 23
8.2. Informative References . . . . . . . . . . . . . . . . . 24
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 26
A.1. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 26
A.2. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 26
A.3. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 26
A.4. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 26
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 27
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1. Introduction
This document defines a YANG [RFC7950] module for a system-level
mechanism, herein called a "keystore". The keystore provides a
centralized location for security sensitive data, as described below.
This module has the following characteristics:
o A 'grouping' for a public/private key pair, and an 'action' for
requesting the system to generate a new private key.
o A 'grouping' for a list of certificates that might be associated
with a public/private key pair, and an 'action' the requesting a
system to generate a certificate signing request.
o An unordered list of pinned certificate sets, where each pinned
certificate set contains an unordered list of pinned certificates.
This structure enables a server to use specific sets of pinned
certificates on a case-by-case basis. For instance, one set of
pinned certificates might be used by an HTTPS-client when
connecting to particular HTTPS servers, while another set of
pinned certificates might be used by a server when authenticating
client connections (e.g., certificate-based client
authentication).
o An unordered list of pinned SSH host key sets, where each pinned
SSH host key set contains an unordered list of pinned SSH host
keys. This structure enables a server to use specific sets of
pinned SSH host-keys on a case-by-case basis. For instance, SSH
clients can be configured to use different sets of pinned SSH host
keys when connecting to different SSH servers.
o A notification to indicate when a certificate is about to expire.
Special consideration has been given for systems that have Trusted
Protection Modules (TPMs). These systems are unique in that the TPM
must be directed to generate new keys (it is not possible to load a
key into a TPM) and it is not possible to backup/restore the TPM's
private keys as configuration.
It is not required that a system has an operating system level
keystore utility to implement this module.
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
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14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2. Tree Diagram
The following tree diagram [I-D.ietf-netmod-yang-tree-diagrams]
provides an overview of the data model for the "ietf-keystore"
module.
module: ietf-keystore
+--rw keystore
+--rw pinned-certificates* [name]
| +--rw name string
| +--rw description? string
| +--rw pinned-certificate* [name]
| +--rw name string
| +--rw data binary
+--rw pinned-host-keys* [name]
+--rw name string
+--rw description? string
+--rw pinned-host-key* [name]
+--rw name string
+--rw data binary
notifications:
+---n certificate-expiration
+--ro certificate instance-identifier
+--ro expiration-date yang:date-and-time
grouping certificate-grouping
+---- certificates
| +---- certificate* [name]
| +---- name? string
| +---- value? binary
+---x generate-certificate-signing-request
+---w input
| +---w subject binary
| +---w attributes? binary
+--ro output
+--ro certificate-signing-request binary
grouping private-key-grouping
+---- algorithm? identityref
+---- private-key? union
+---- public-key? binary
+---x generate-private-key
+---w input
+---w algorithm identityref
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3. Example Usage
The following example illustrates what a configured keystore might
look like.
manufacturers-root-ca-certs
Certificates built into the device for authenticating
manufacturer-signed objects, such as TLS server certificates,
vouchers, etc.. Note, though listed here, these are not
configurable; any attempt to do so will be denied.
Manufacturer Root CA cert 1
base64encodedvalue==
Manufacturer Root CA cert 2
base64encodedvalue==
explicitly-trusted-client-certs
Specific client authentication certificates for explicitly
trusted clients. These are needed for client certificates
that are not signed by a pinned CA.
George Jetson
base64encodedvalue==
explicitly-trusted-server-certs
Specific server authentication certificates for explicitly
trusted servers. These are needed for server certificates
that are not signed by a pinned CA.
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Fred Flintstone
base64encodedvalue==
deployment-specific-ca-certs
Trust anchors (i.e. CA certs) that are used to authenticate
client connections. Clients are authenticated if their
certificate has a chain of trust to one of these configured
CA certificates.
ca.example.com
base64encodedvalue==
common-ca-certs
Trusted certificates to authenticate common HTTPS servers.
These certificates are similar to those that might be
shipped with a web browser.
ex-certificate-authority
base64encodedvalue==
explicitly-trusted-ssh-host-keys
Trusted SSH host keys used to authenticate SSH servers.
These host keys would be analogous to those stored in
a known_hosts file in OpenSSH.
corp-fw1
base64encodedvalue==
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The following example illustrates the "certificate-expiration"
notification in use with the NETCONF protocol.
[ note: '\' line wrapping for formatting only]
2016-07-08T00:01:00Z
/ks:keystore/ks:keys/ks:key[ks:name='ex-rsa-key']/ks:certifica\
tes/ks:certificate[ks:name='ex-rsa-cert']
2016-08-08T14:18:53-05:00
The following example module has been constructed to illustrate the
groupings defined in the "ietf-keystore" module.
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module ex-keystore-usage {
yang-version 1.1;
namespace "http://example.com/ns/example-keystore-usage";
prefix "eku";
import ietf-keystore {
prefix ks;
reference
"RFC VVVV: YANG Data Model for a 'Keystore' Mechanism";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
Author: Kent Watsen ";
description
"This module uses the groupings defines the keystore draft
for illustration.";
revision "YYYY-MM-DD" {
description
"Initial version";
}
container key {
uses ks:private-key-grouping;
uses ks:certificate-grouping;
description
"A container of certificates, and an action to generate
a certificate signing request.";
}
}
The following example illustrates what a configured key might look
like. This example uses the "ex-keystore-usage" module above.
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[ note: '\' line wrapping for formatting only]
ks:\
secp521r1
base64encodedvalue==
base64encodedvalue==
domain certificate
base64encodedvalue==
The following example illustrates the "generate-certificate-signing-
request" action in use with the NETCONF protocol. This example uses
the "ex-keystore-usage" module above.
REQUEST
-------
base64encodedvalue==
base64encodedvalue==
RESPONSE
--------
base64encodedvalue==
The following example illustrates the "generate-private-key" action
in use with the NETCONF protocol. This example uses the "ex-
keystore-usage" module above.
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REQUEST
-------
[ note: '\' line wrapping for formatting only]
ks:secp521r1
RESPONSE
--------
4. YANG Module
This YANG module imports modules defined in [RFC6536] and [RFC6991].
This module uses data types defined in [RFC2315], [RFC2986],
[RFC3447], [RFC4253], [RFC5280], [RFC5915], and [ITU.X690.1994].
This module uses algorithms defined in [RFC3447] and [RFC5480].
file "ietf-keystore@2017-10-30.yang"
module ietf-keystore {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-keystore";
prefix "ks";
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 6536: Network Configuration Protocol (NETCONF) Access
Control Model";
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}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
Author: Kent Watsen
";
description
"This module defines a keystore to centralize management
of security credentials.
Copyright (c) 2017 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 VVVV; see
the RFC itself for full legal notices.";
revision "2017-10-30" {
description
"Initial version";
reference
"RFC VVVV: YANG Data Model for a 'Keystore' Mechanism";
}
// Identities
identity key-algorithm {
description
"Base identity from which all key-algorithms are derived.";
}
identity rsa1024 {
base key-algorithm;
description
"The RSA algorithm using a 1024-bit key.";
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reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.";
}
identity rsa2048 {
base key-algorithm;
description
"The RSA algorithm using a 2048-bit key.";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.";
}
identity rsa3072 {
base key-algorithm;
description
"The RSA algorithm using a 3072-bit key.";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.";
}
identity rsa4096 {
base key-algorithm;
description
"The RSA algorithm using a 4096-bit key.";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.";
}
identity rsa7680 {
base key-algorithm;
description
"The RSA algorithm using a 7680-bit key.";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.";
}
identity rsa15360 {
base key-algorithm;
description
"The RSA algorithm using a 15360-bit key.";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.";
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}
identity secp192r1 {
base key-algorithm;
description
"The secp192r1 algorithm.";
reference
"RFC5480:
Elliptic Curve Cryptography Subject Public Key Information.";
}
identity secp256r1 {
base key-algorithm;
description
"The secp256r1 algorithm.";
reference
"RFC5480:
Elliptic Curve Cryptography Subject Public Key Information.";
}
identity secp384r1 {
base key-algorithm;
description
"The secp384r1 algorithm.";
reference
"RFC5480:
Elliptic Curve Cryptography Subject Public Key Information.";
}
identity secp521r1 {
base key-algorithm;
description
"The secp521r1 algorithm.";
reference
"RFC5480:
Elliptic Curve Cryptography Subject Public Key Information.";
}
// typedefs
typedef pinned-certificates {
type leafref {
path "/ks:keystore/ks:pinned-certificates/ks:name";
}
description
"This typedef enables importing modules to easily define a
reference to pinned-certificates. Use of this type also
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impacts the YANG tree diagram output.";
reference
"I-D.ietf-netmod-yang-tree-diagrams: YANG Tree Diagrams";
}
typedef pinned-host-keys {
type leafref {
path "/ks:keystore/ks:pinned-host-keys/ks:name";
}
description
"This typedef enables importing modules to easily define a
reference to pinned-host-keys. Use of this type also
impacts the YANG tree diagram output.";
reference
"I-D.ietf-netmod-yang-tree-diagrams: YANG Tree Diagrams";
}
// groupings
grouping private-key-grouping {
description
"A private/public key pair, and an action to request the
system to generate a private key.";
leaf algorithm {
type identityref {
base "key-algorithm";
}
description
"Identifies the key's algorithm. More specifically, this
leaf specifies how the 'private-key' and 'public-key'
binary leafs are encoded.";
}
leaf private-key {
nacm:default-deny-all;
type union {
type binary;
type enumeration {
enum "hardware-protected" {
description
"The private key is inaccessible due to being
protected by a cryptographic hardware module
(e.g., a TPM).";
}
}
}
must "../algorithm";
description
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"A binary that contains the value of the private key. The
interpretation of the content is defined by the key
algorithm. For example, a DSA key is an integer, an RSA
key is represented as RSAPrivateKey as defined in
[RFC3447], and an Elliptic Curve Cryptography (ECC) key
is represented as ECPrivateKey as defined in [RFC5915]";
reference
"RFC 3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.
RFC 5915: Elliptic Curve Private Key Structure.";
}
leaf public-key {
type binary;
must "../algorithm";
must "../private-key";
description
"A binary that contains the value of the public key. The
interpretation of the content is defined by the key
algorithm. For example, a DSA key is an integer, an RSA
key is represented as RSAPublicKey as defined in
[RFC3447], and an Elliptic Curve Cryptography (ECC) key
is represented using the 'publicKey' described in
[RFC5915]";
reference
"RFC 3447: Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications Version 2.1.
RFC 5915: Elliptic Curve Private Key Structure.";
}
action generate-private-key {
description
"Requests the device to generate a private key using the
specified key algorithm. This action is primarily to
support cryptographic processors that must generate
the private key themselves. The resulting key is
considered operational state and hence only present
in the .";
input {
leaf algorithm {
type identityref {
base "key-algorithm";
}
mandatory true;
description
"The algorithm to be used when generating the key.";
}
}
} // end generate-private-key
}
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grouping certificate-grouping {
description
"A container of certificates, and an action to generate
a certificate signing request.";
container certificates {
description
"Certificates associated with this key. More than one
certificate supports, for instance, a TPM-protected
key that has both IDevID and LDevID certificates
associated.";
list certificate {
key name;
description
"A certificate for this private key.";
leaf name {
type string;
description
"An arbitrary name for the certificate.";
}
leaf value {
type binary;
description
"A 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 the certificate itself as well
as any intermediate certificates leading up to a trust
anchor certificate. The trust anchor certificate MAY
be included as well.";
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).";
}
}
}
action generate-certificate-signing-request {
description
"Generates a certificate signing request structure for
the associated private key using the passed subject and
attribute values. The specified assertions need to be
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appropriate for the certificate's use. For example,
an entity certificate for a TLS server SHOULD have
values that enable clients to satisfy RFC 6125
processing.";
input {
leaf subject {
type binary;
mandatory true;
description
"The 'subject' field from the CertificationRequestInfo
structure as specified by RFC 2986, Section 4.1 encoded
using the ASN.1 distinguished encoding rules (DER), as
specified in ITU-T X.690.";
reference
"RFC 2986:
PKCS #10: Certification Request Syntax Specification
Version 1.7.
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 attributes {
type binary;
description
"The 'attributes' field from the CertificationRequestInfo
structure as specified by RFC 2986, Section 4.1 encoded
using the ASN.1 distinguished encoding rules (DER), as
specified in ITU-T X.690.";
reference
"RFC 2986:
PKCS #10: Certification Request Syntax Specification
Version 1.7.
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).";
}
}
output {
leaf certificate-signing-request {
type binary;
mandatory true;
description
"A CertificationRequest structure as specified by RFC
2986, Section 4.1 encoded using the ASN.1 distinguished
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encoding rules (DER), as specified in ITU-T X.690.";
reference
"RFC 2986:
PKCS #10: Certification Request Syntax Specification
Version 1.7.
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).";
}
}
}
}
// protocol accessible nodes
container keystore {
nacm:default-deny-write;
description
"The keystore contains X.509 certificates and SSH host keys.";
list pinned-certificates {
key name;
description
"A list of pinned certificates. These certificates can be
used by a server to authenticate clients, or by clients to
authenticate servers. Each list of pinned certificates
SHOULD be specific to a purpose, as the list as a whole
may be referenced by other modules. For instance, a
NETCONF server's configuration might use a specific list
of pinned certificates for when authenticating NETCONF
client connections.";
leaf name {
type string;
description
"An arbitrary name for this list of pinned certificates.";
}
leaf description {
type string;
description
"An arbitrary description for this list of pinned
certificates.";
}
list pinned-certificate {
key name;
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description
"A pinned certificate.";
leaf name {
type string;
description
"An arbitrary name for this pinned certificate. The
name must be unique across all lists of pinned
certificates (not just this list) so that leafrefs
from another module can resolve to unique values.";
}
leaf data {
type binary;
mandatory true;
description
"An X.509 v3 certificate structure as specified by RFC
5280, Section 4 encoded using the 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).";
}
}
}
list pinned-host-keys {
key name;
description
"A list of pinned host keys. These pinned host-keys can
be used by clients to authenticate SSH servers. Each
list of pinned host keys SHOULD be specific to a purpose,
so the list as a whole may be referenced by other modules.
For instance, a NETCONF client's configuration might
point to a specific list of pinned host keys for when
authenticating specific SSH servers.";
leaf name {
type string;
description
"An arbitrary name for this list of pinned SSH host keys.";
}
leaf description {
type string;
description
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"An arbitrary description for this list of pinned SSH host
keys.";
}
list pinned-host-key {
key name;
description
"A pinned host key.";
leaf name {
type string;
description
"An arbitrary name for this pinned host-key. Must be
unique across all lists of pinned host-keys (not just
this list) so that a leafref to it from another module
can resolve to unique values.";
}
leaf data {
type binary;
mandatory true;
description
"The binary public key data for this SSH key, as
specified by RFC 4253, Section 6.6, i.e.:
string certificate or public key format
identifier
byte[n] key/certificate data.";
reference
"RFC 4253: The Secure Shell (SSH) Transport Layer
Protocol";
}
}
}
}
notification certificate-expiration {
description
"A notification indicating that a configured certificate is
either about to expire or has already expired. When to send
notifications is an implementation specific decision, but
it is RECOMMENDED that a notification be sent once a month
for 3 months, then once a week for four weeks, and then once
a day thereafter.";
leaf certificate {
type instance-identifier;
mandatory true;
description
"Identifies which certificate is expiring or is expired.";
}
leaf expiration-date {
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type yang:date-and-time;
mandatory true;
description
"Identifies the expiration date on the certificate.";
}
}
}
5. Security Considerations
The YANG module defined in this document is designed to be accessed
via YANG based management protocols, such as NETCONF [RFC6241] and
RESTCONF [RFC8040]. Both of these protocols have mandatory-to-
implement secure transport layers (e.g., SSH, TLS) with mutual
authentication.
The NETCONF access control model (NACM) [RFC6536] provides the means
to restrict access for particular users to a pre-configured subset of
all available protocol operations and content.
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations. These are the subtrees and data nodes
and their sensitivity/vulnerability:
/: The entire data tree defined by this module is sensitive to
write operations. For instance, the addition or removal of
keys, certificates, trusted anchors, etc., can dramatically
alter the implemented security policy. This being the case,
the top-level node in this module is marked with the NACM value
'default-deny-write'.
/keystore/keys/key/private-key: When writing this node,
implementations MUST ensure that the strength of the key being
configured is not greater than the strength of the underlying
secure transport connection over which it is communicated.
Implementations SHOULD fail the write-request if ever the
strength of the private key is greater then the strength of the
underlying transport, and alert the client that the strength of
the key may have been compromised. Additionally, when deleting
this node, implementations SHOULD automatically (without
explicit request) zeroize these keys in the most secure manner
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available, so as to prevent the remnants of their persisted
storage locations from being analyzed in any meaningful way.
Some of the readable data nodes in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control read access (e.g., via get, get-config, or
notification) to these data nodes. These are the subtrees and data
nodes and their sensitivity/vulnerability:
/keystore/keys/key/private-key: This node is additionally
sensitive to read operations such that, in normal use cases, it
should never be returned to a client. The best reason for
returning this node is to support backup/restore type
workflows. This being the case, this node is marked with the
NACM value 'default-deny-all'.
Some of the operations in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control access to these operations. These are the
operations and their sensitivity/vulnerability:
generate-certificate-signing-request: For this action, it is
RECOMMENDED that implementations assert channel binding
[RFC5056], so as to ensure that the application layer that sent
the request is the same as the device authenticated when the
secure transport layer was established.
6. IANA Considerations
6.1. 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-keystore
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
6.2. The YANG Module Names Registry
This document registers one YANG module in the YANG Module Names
registry [RFC6020]. Following the format in [RFC6020], the the
following registration is requested:
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name: ietf-keystore
namespace: urn:ietf:params:xml:ns:yang:ietf-keystore
prefix: ks
reference: RFC VVVV
7. Acknowledgements
The authors would like to thank for following for lively discussions
on list and in the halls (ordered by last name): Andy Bierman, Martin
Bjorklund, Benoit Claise, Mehmet Ersue, Balazs Kovacs, David
Lamparter, Alan Luchuk, Ladislav Lhotka, Radek Krejci, Tom Petch,
Juergen Schoenwaelder; Phil Shafer, Sean Turner, and Bert Wijnen.
8. References
8.1. Normative References
[ITU.X690.1994]
International Telecommunications Union, "Information
Technology - ASN.1 encoding rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and
Distinguished Encoding Rules (DER)", ITU-T Recommendation
X.690, 1994.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
.
[RFC2315] Kaliski, B., "PKCS #7: Cryptographic Message Syntax
Version 1.5", RFC 2315, DOI 10.17487/RFC2315, March 1998,
.
[RFC2986] Nystrom, M. and B. Kaliski, "PKCS #10: Certification
Request Syntax Specification Version 1.7", RFC 2986,
DOI 10.17487/RFC2986, November 2000,
.
[RFC3447] Jonsson, J. and B. Kaliski, "Public-Key Cryptography
Standards (PKCS) #1: RSA Cryptography Specifications
Version 2.1", RFC 3447, DOI 10.17487/RFC3447, February
2003, .
[RFC4253] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
Transport Layer Protocol", RFC 4253, DOI 10.17487/RFC4253,
January 2006, .
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[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,
.
[RFC5480] Turner, S., Brown, D., Yiu, K., Housley, R., and T. Polk,
"Elliptic Curve Cryptography Subject Public Key
Information", RFC 5480, DOI 10.17487/RFC5480, March 2009,
.
[RFC5915] Turner, S. and D. Brown, "Elliptic Curve Private Key
Structure", RFC 5915, DOI 10.17487/RFC5915, June 2010,
.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
.
[RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration
Protocol (NETCONF) Access Control Model", RFC 6536,
DOI 10.17487/RFC6536, March 2012,
.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
.
8.2. Informative References
[I-D.ietf-netmod-yang-tree-diagrams]
Bjorklund, M. and L. Berger, "YANG Tree Diagrams", draft-
ietf-netmod-yang-tree-diagrams-02 (work in progress),
October 2017.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
.
[RFC4211] Schaad, J., "Internet X.509 Public Key Infrastructure
Certificate Request Message Format (CRMF)", RFC 4211,
DOI 10.17487/RFC4211, September 2005,
.
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[RFC5056] Williams, N., "On the Use of Channel Bindings to Secure
Channels", RFC 5056, DOI 10.17487/RFC5056, November 2007,
.
[RFC5914] Housley, R., Ashmore, S., and C. Wallace, "Trust Anchor
Format", RFC 5914, DOI 10.17487/RFC5914, June 2010,
.
[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,
.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, .
[Std-802.1AR-2009]
IEEE SA-Standards Board, "IEEE Standard for Local and
metropolitan area networks - Secure Device Identity",
December 2009, .
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Appendix A. Change Log
A.1. 00 to 01
o Replaced the 'certificate-chain' structures with PKCS#7
structures. (Issue #1)
o Added 'private-key' as a configurable data node, and removed the
'generate-private-key' and 'load-private-key' actions. (Issue #2)
o Moved 'user-auth-credentials' to the ietf-ssh-client module.
(Issues #4 and #5)
A.2. 01 to 02
o Added back 'generate-private-key' action.
o Removed 'RESTRICTED' enum from the 'private-key' leaf type.
o Fixed up a few description statements.
A.3. 02 to 03
o Changed draft's title.
o Added missing references.
o Collapsed sections and levels.
o Added RFC 8174 to Requirements Language Section.
o Renamed 'trusted-certificates' to 'pinned-certificates'.
o Changed 'public-key' from config false to config true.
o Switched 'host-key' from OneAsymmetricKey to definition from RFC
4253.
A.4. 03 to 04
o Added typedefs around leafrefs to common keystore paths
o Now tree diagrams reference ietf-netmod-yang-tree-diagrams
o Removed Design Considerations section
o Moved key and certificate definitions from data tree to groupings
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Author's Address
Kent Watsen
Juniper Networks
EMail: kwatsen@juniper.net
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