NETCONF Working Group K. Watsen
Internet-Draft Juniper Networks
Intended status: Standards Track G. Wu
Expires: September 14, 2017 Cisco Systems
March 13, 2017
TLS Client and Server Models
draft-ietf-netconf-tls-client-server-02
Abstract
This document defines three YANG modules: the first defines groupings
for a generic TLS client, the second defines groupings for a generic
TLS server, and the third defines common identities and groupings
used by both the client and the server. It is intended that these
groupings will be used by applications using the TLS protocol.
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.
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 I-D.ietf-netconf-keystore
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
o "YYYY" --> the assigned RFC value for I-D.ietf-netconf-keystore
Artwork in this document contains placeholder values for the date of
publication of this draft. Please apply the following replacement:
o "2017-03-13" --> the publication date of this draft
The following two Appendix sections are to be removed prior to
publication:
o Appendix A. Change Log
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o Appendix B. Open Issues
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 http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 14, 2017.
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
(http://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
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 4
2. The TLS Client Model . . . . . . . . . . . . . . . . . . . . 4
2.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 5
2.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 5
3. The TLS Server Model . . . . . . . . . . . . . . . . . . . . 8
3.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 8
3.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 9
3.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 9
4. The TLS Common Model . . . . . . . . . . . . . . . . . . . . 12
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4.1. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 13
4.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 13
4.3. YANG Model . . . . . . . . . . . . . . . . . . . . . . . 13
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 . . . . . . . . . . . . . . . . . . . . . . 22
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 23
8.1. Normative References . . . . . . . . . . . . . . . . . . 23
8.2. Informative References . . . . . . . . . . . . . . . . . 24
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 25
A.1. server-model-09 to 00 . . . . . . . . . . . . . . . . . . 25
A.2. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 25
A.3. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 25
Appendix B. Open Issues . . . . . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 25
1. Introduction
This document defines three YANG [RFC7950] modules: the first defines
a grouping for a generic TLS client, the second defines a grouping
for a generic TLS server, and the third defines identities and
groupings common to both the client and the server (TLS is defined in
[RFC5246]). It is intended that these groupings will be used by
applications using the TLS protocol. For instance, these groupings
could be used to help define the data model for an HTTPS [RFC2818]
server or a NETCONF over TLS [RFC7589] based server.
The client and server YANG modules in this document each define one
grouping, which is focused on just TLS-specific configuration, and
specifically avoids any transport-level configuration, such as what
ports to listen-on or connect-to. This enables applications the
opportunity to define their own strategy for how the underlying TCP
connection is established. For instance, applications supporting
NETCONF Call Home [RFC8071] could use the grouping for the TLS parts
it provides, while adding data nodes for the TCP-level call-home
configuration.
1.1. Terminology
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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1.2. Tree Diagrams
A simplified graphical representation of the data models is used in
this document. The meaning of the symbols in these diagrams is as
follows:
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" means configuration
(read-write) and "ro" state data (read-only).
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. The TLS Client Model
The TLS client model presented in this section contains one YANG
grouping, to just configure the TLS client omitting, for instance,
any configuration for which IP address or port the client should
connect to.
This grouping references data nodes defined by the keystore model
[I-D.ietf-netconf-keystore]. For instance, a reference to the
keystore model is made to indicate which trusted CA certificate a
client should use to authenticate the server's certificate.
2.1. Tree Diagram
The following tree diagram presents the data model for the grouping
defined in the ietf-tls-client module. Please see Section 1.2 for
tree diagram notation.
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module: ietf-tls-client
groupings:
tls-client-grouping
+---- server-auth
| +---- trusted-ca-certs?
| | -> /ks:keystore/trusted-certificates/name
| +---- trusted-server-certs?
| -> /ks:keystore/trusted-certificates/name
+---- client-auth
| +---- (auth-type)?
| +--:(certificate)
| +---- certificate? leafref
+---- hello-params {tls-client-hello-params-config}?
+---- tls-versions
| +---- tls-version* identityref
+---- cipher-suites
+---- cipher-suite* identityref
2.2. Example Usage
This section shows how it would appear if the tls-client-grouping
were populated with some data. This example is consistent with the
examples presented in Section 2.2 of [I-D.ietf-netconf-keystore].
deployment-specific-ca-certs
explicitly-trusted-client-certs
builtin-idevid-cert
2.3. YANG Model
This YANG module has a normative references to [RFC6991] and
[I-D.ietf-netconf-keystore].
file "ietf-tls-client@2017-03-13.yang"
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module ietf-tls-client {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-tls-client";
prefix "tlsc";
import ietf-tls-common {
prefix tlscom;
revision-date 2017-03-13; // stable grouping definitions
reference
"RFC XXXX: TLS Client and Server Models";
}
import ietf-keystore {
prefix ks;
reference
"RFC YYYY: Keystore Model";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
Author: Kent Watsen
";
description
"This module defines a reusable grouping for a TLS client that
can be used as a basis for specific TLS client instances.
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.";
revision "2017-03-13" {
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description
"Initial version";
reference
"RFC XXXX: TLS Client and Server Models";
}
feature tls-client-hello-params-config {
description
"TLS hello message parameters are configurable on a TLS
client.";
}
grouping tls-client-grouping {
description
"A reusable grouping for configuring a TLS client without
any consideration for how an underlying TCP session is
established.";
container server-auth {
description
"Trusted server identities.";
leaf trusted-ca-certs {
type leafref {
path "/ks:keystore/ks:trusted-certificates/ks:name";
}
description
"A reference to a list of certificate authority (CA)
certificates used by the TLS client to authenticate
TLS server certificates.";
}
leaf trusted-server-certs {
type leafref {
path "/ks:keystore/ks:trusted-certificates/ks:name";
}
description
"A reference to a list of server certificates used by
the TLS client to authenticate TLS server certificates.
A server certificate is authenticated if it is an
exact match to a configured trusted server certificate.";
}
}
container client-auth {
description
"The credentials used by the client to authenticate to
the TLS server.";
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choice auth-type {
description
"The authentication type.";
leaf certificate {
type leafref {
path "/ks:keystore/ks:keys/ks:key/ks:certificates"
+ "/ks:certificate/ks:name";
}
description
"A certificates to be used for user authentication.";
}
}
}
container hello-params {
if-feature tls-client-hello-params-config;
uses tlscom:hello-params-grouping;
description
"Configurable parameters for the TLS hello message.";
}
} // end tls-client-grouping
}
3. The TLS Server Model
The TLS server model presented in this section contains one YANG
grouping, for just the TLS-level configuration omitting, for
instance, configuration for which ports to open to listen for
connections on.
This grouping references data nodes defined by the keystore model
[I-D.ietf-netconf-keystore]. For instance, a reference to the
keystore model is made to indicate which certificate a server should
present.
3.1. Tree Diagram
The following tree diagram presents the data model for the grouping
defined in the ietf-tls-server module. Please see Section 1.2 for
tree diagram notation.
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module: ietf-tls-server
groupings:
tls-server-grouping
+---- certificates
| +---- certificate* [name]
| +---- name? leafref
+---- client-auth
| +---- trusted-ca-certs?
| | -> /ks:keystore/trusted-certificates/name
| +---- trusted-client-certs?
| -> /ks:keystore/trusted-certificates/name
+---- hello-params {tls-server-hello-params-config}?
+---- tls-versions
| +---- tls-version* identityref
+---- cipher-suites
+---- cipher-suite* identityref
3.2. Example Usage
This section shows how it would appear if the tls-server-grouping
were populated with some data. This example is consistent with the
examples presented in Section 2.2 of [I-D.ietf-netconf-keystore].
tls-ec-cert
deployment-specific-ca-certs
explicitly-trusted-client-certs
3.3. YANG Model
This YANG module has a normative references to [RFC6991], and
[I-D.ietf-netconf-keystore].
file "ietf-tls-server@2017-03-13.yang"
module ietf-tls-server {
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yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-tls-server";
prefix "tlss";
import ietf-tls-common {
prefix tlscom;
revision-date 2017-03-13; // stable grouping definitions
reference
"RFC XXXX: TLS Client and Server Models";
}
import ietf-keystore {
prefix ks;
reference
"RFC YYYY: Keystore Model";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
Author: Kent Watsen
";
description
"This module defines a reusable grouping for a TLS server that
can be used as a basis for specific TLS server instances.
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.";
revision "2017-03-13" {
description
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"Initial version";
reference
"RFC XXXX: TLS Client and Server Models";
}
feature tls-server-hello-params-config {
description
"TLS hello message parameters are configurable on a TLS
server.";
}
// grouping
grouping tls-server-grouping {
description
"A reusable grouping for configuring a TLS server without
any consideration for how underlying TCP sessions are
established.";
container certificates {
description
"The list of certificates the TLS server will present when
establishing a TLS connection in its Certificate message,
as defined in Section 7.4.2 in RRC 5246.";
reference
"RFC 5246:
The Transport Layer Security (TLS) Protocol Version 1.2";
list certificate {
key name;
min-elements 1;
description
"An unordered list of certificates the TLS server can pick
from when sending its Server Certificate message.";
reference
"RFC 5246: The TLS Protocol, Section 7.4.2";
leaf name {
type leafref {
path "/ks:keystore/ks:keys/ks:key/ks:certificates/"
+ "ks:certificate/ks:name";
}
description
"The name of the certificate in the keystore.";
}
}
}
container client-auth {
description
"A reference to a list of trusted certificate authority (CA)
certificates and a reference to a list of trusted client
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certificates.";
leaf trusted-ca-certs {
type leafref {
path "/ks:keystore/ks:trusted-certificates/ks:name";
}
description
"A reference to a list of certificate authority (CA)
certificates used by the TLS server to authenticate
TLS client certificates.";
}
leaf trusted-client-certs {
type leafref {
path "/ks:keystore/ks:trusted-certificates/ks:name";
}
description
"A reference to a list of client certificates used by
the TLS server to authenticate TLS client certificates.
A clients certificate is authenticated if it is an
exact match to a configured trusted client certificate.";
}
}
container hello-params {
if-feature tls-server-hello-params-config;
uses tlscom:hello-params-grouping;
description
"Configurable parameters for the TLS hello message.";
}
} // end tls-server-grouping
}
4. The TLS Common Model
The TLS common model presented in this section contains identities
and groupings common to both TLS clients and TLS servers. The hello-
params-grouping can be used to configure the list of TLS algorithms
permitted by the TLS client or TLS server. The lists of algorithms
are ordered such that, if multiple algorithms are permitted by the
client, the algorithm that appears first in its list that is also
permitted by the server is used for the TLS transport layer
connection. The ability to restrict the the algorithms allowed is
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provided in this grouping for TLS clients and TLS servers that are
capable of doing so and may serve to make TLS clients and TLS servers
compliant with security policies.
Features are defined for algorithms that are OPTIONAL or are not
widely supported by popular implementations. Note that the list of
algorithms is not exhaustive.
4.1. Tree Diagram
The following tree diagram presents the data model for the grouping
defined in the ietf-tls-common module. Please see Section 1.2 for
tree diagram notation.
module: ietf-tls-common
groupings:
hello-params-grouping
+---- tls-versions
| +---- tls-version* identityref
+---- cipher-suites
+---- cipher-suite* identityref
4.2. Example Usage
This section shows how it would appear if the transport-params-
grouping were populated with some data.
tls-1.2
ecdhe-rsa-with-3des-ede-cbc-sha
dhe-rsa-with-aes-128-cbc-sha
rsa-with-aes-128-cbc-sha
rsa-with-3des-ede-cbc-sha
4.3. YANG Model
This YANG module has a normative references to [RFC4492], [RFC5246],
[RFC5288], and [RFC5289].
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file "ietf-tls-common@2017-03-13.yang"
module ietf-tls-common {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-tls-common";
prefix "tlscom";
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
Author: Kent Watsen
Author: Gary Wu
";
description
"This module defines a common features, identities, and groupings
for Transport Layer Security (TLS).
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 XXXX; see
the RFC itself for full legal notices.";
revision "2017-03-13" {
description
"Initial version";
reference
"RFC XXXX: TLS Client and Server Models";
}
// features
feature tls-ecc {
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description
"Elliptic Curve Cryptography (ECC) is supported for TLS.";
reference
"RFC 4492: Elliptic Curve Cryptography (ECC) Cipher Suites
for Transport Layer Security (TLS)";
}
feature tls-dhe {
description
"Ephemeral Diffie-Hellman key exchange is supported for TLS.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
feature tls-3des {
description
"The Triple-DES block cipher is supported for TLS.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
feature tls-gcm {
description
"The Galois/Counter Mode authenticated encryption mode is
supported for TLS.";
reference
"RFC 5288: AES Galois Counter Mode (GCM) Cipher Suites for TLS";
}
feature tls-sha2 {
description
"The SHA2 family of cryptographic hash functions is supported
for TLS.";
reference
"FIPS PUB 180-4: Secure Hash Standard (SHS)";
}
// identities
identity tls-version-base {
description
"Base identity used to identify TLS protocol versions.";
}
identity tls-1.2 {
base tls-version-base;
description
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"TLS protocol version 1.2.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity cipher-suite-base {
description
"Base identity used to identify TLS cipher suites.";
}
identity rsa-with-aes-128-cbc-sha {
base cipher-suite-base;
description
"Cipher suite TLS_RSA_WITH_AES_128_CBC_SHA.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity rsa-with-aes-256-cbc-sha {
base cipher-suite-base;
description
"Cipher suite TLS_RSA_WITH_AES_256_CBC_SHA.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity rsa-with-aes-128-cbc-sha256 {
base cipher-suite-base;
if-feature tls-sha2;
description
"Cipher suite TLS_RSA_WITH_AES_128_CBC_SHA256.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity rsa-with-aes-256-cbc-sha256 {
base cipher-suite-base;
if-feature tls-sha2;
description
"Cipher suite TLS_RSA_WITH_AES_256_CBC_SHA256.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
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identity dhe-rsa-with-aes-128-cbc-sha {
base cipher-suite-base;
if-feature tls-dhe;
description
"Cipher suite TLS_DHE_RSA_WITH_AES_128_CBC_SHA.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity dhe-rsa-with-aes-256-cbc-sha {
base cipher-suite-base;
if-feature tls-dhe;
description
"Cipher suite TLS_DHE_RSA_WITH_AES_256_CBC_SHA.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity dhe-rsa-with-aes-128-cbc-sha256 {
base cipher-suite-base;
if-feature "tls-dhe and tls-sha2";
description
"Cipher suite TLS_DHE_RSA_WITH_AES_128_CBC_SHA256.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity dhe-rsa-with-aes-256-cbc-sha256 {
base cipher-suite-base;
if-feature "tls-dhe and tls-sha2";
description
"Cipher suite TLS_DHE_RSA_WITH_AES_256_CBC_SHA256.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity ecdhe-ecdsa-with-aes-128-cbc-sha256 {
base cipher-suite-base;
if-feature "tls-ecc and tls-sha2";
description
"Cipher suite TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
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}
identity ecdhe-ecdsa-with-aes-256-cbc-sha384 {
base cipher-suite-base;
if-feature "tls-ecc and tls-sha2";
description
"Cipher suite TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity ecdhe-rsa-with-aes-128-cbc-sha256 {
base cipher-suite-base;
if-feature "tls-ecc and tls-sha2";
description
"Cipher suite TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity ecdhe-rsa-with-aes-256-cbc-sha384 {
base cipher-suite-base;
if-feature "tls-ecc and tls-sha2";
description
"Cipher suite TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity ecdhe-ecdsa-with-aes-128-gcm-sha256 {
base cipher-suite-base;
if-feature "tls-ecc and tls-gcm and tls-sha2";
description
"Cipher suite TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity ecdhe-ecdsa-with-aes-256-gcm-sha384 {
base cipher-suite-base;
if-feature "tls-ecc and tls-gcm and tls-sha2";
description
"Cipher suite TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384.";
reference
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"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity ecdhe-rsa-with-aes-128-gcm-sha256 {
base cipher-suite-base;
if-feature "tls-ecc and tls-gcm and tls-sha2";
description
"Cipher suite TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity ecdhe-rsa-with-aes-256-gcm-sha384 {
base cipher-suite-base;
if-feature "tls-ecc and tls-gcm and tls-sha2";
description
"Cipher suite TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384.";
reference
"RFC 5289: TLS Elliptic Curve Cipher Suites with
SHA-256/384 and AES Galois Counter Mode (GCM)";
}
identity rsa-with-3des-ede-cbc-sha {
base cipher-suite-base;
if-feature tls-3des;
description
"Cipher suite TLS_RSA_WITH_3DES_EDE_CBC_SHA.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
}
identity ecdhe-rsa-with-3des-ede-cbc-sha {
base cipher-suite-base;
if-feature "tls-ecc and tls-3des";
description
"Cipher suite TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA.";
reference
"RFC 4492: Elliptic Curve Cryptography (ECC) Cipher Suites
for Transport Layer Security (TLS)";
}
identity ecdhe-rsa-with-aes-128-cbc-sha {
base cipher-suite-base;
if-feature "tls-ecc";
description
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"Cipher suite TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA.";
reference
"RFC 4492: Elliptic Curve Cryptography (ECC) Cipher Suites
for Transport Layer Security (TLS)";
}
identity ecdhe-rsa-with-aes-256-cbc-sha {
base cipher-suite-base;
if-feature "tls-ecc";
description
"Cipher suite TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA.";
reference
"RFC 4492: Elliptic Curve Cryptography (ECC) Cipher Suites
for Transport Layer Security (TLS)";
}
// groupings
grouping hello-params-grouping {
description
"A reusable grouping for TLS hello message parameters. For
configurable parameters, a zero-element leaf-list indicates the
system default configuration for that parameter.";
reference
"RFC 5246: The Transport Layer Security (TLS) Protocol
Version 1.2";
container tls-versions {
description
"Parameters regarding TLS versions.";
leaf-list tls-version {
type identityref {
base tls-version-base;
}
description
"Allowed TLS protocol versions.";
}
}
container cipher-suites {
description
"Parameters regarding cipher suites.";
leaf-list cipher-suite {
type identityref {
base cipher-suite-base;
}
ordered-by user;
description
"Cipher suites in order of descending preference.";
}
}
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}
}
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
references to keys, certificates, trusted anchors, etc., can
dramatically alter the implemented security policy. However,
no NACM annotations are applied as the data SHOULD be editable
by users other than a designated 'recovery session'.
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:
NONE
Some of the RPC 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:
NONE
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6. IANA Considerations
6.1. The IETF XML Registry
This document registers three URIs in the IETF XML registry
[RFC3688]. Following the format in [RFC3688], the following
registrations are requested:
URI: urn:ietf:params:xml:ns:yang:ietf-tls-client
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-tls-server
Registrant Contact: The NETCONF WG of the IETF.
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-tls-common
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 three YANG modules in the YANG Module Names
registry [RFC7950]. Following the format in [RFC7950], the the
following registrations are requested:
name: ietf-tls-client
namespace: urn:ietf:params:xml:ns:yang:ietf-tls-client
prefix: tlsc
reference: RFC XXXX
name: ietf-tls-server
namespace: urn:ietf:params:xml:ns:yang:ietf-tls-server
prefix: tlss
reference: RFC XXXX
name: ietf-tls-common
namespace: urn:ietf:params:xml:ns:yang:ietf-tls-common
prefix: tlss
reference: RFC XXXX
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, David Lamparter, Alan Luchuk,
Ladislav Lhotka, Radek Krejci, Tom Petch, Juergen Schoenwaelder, Phil
Shafer, Sean Turner, and Bert Wijnen.
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8. References
8.1. Normative References
[I-D.ietf-netconf-keystore]
Watsen, K. and G. Wu, "Keystore Model", draft-ietf-
netconf-keystore-00 (work in progress), October 2016.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
.
[RFC4492] Blake-Wilson, S., Bolyard, N., Gupta, V., Hawk, C., and B.
Moeller, "Elliptic Curve Cryptography (ECC) Cipher Suites
for Transport Layer Security (TLS)", RFC 4492,
DOI 10.17487/RFC4492, May 2006,
.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
.
[RFC5288] Salowey, J., Choudhury, A., and D. McGrew, "AES Galois
Counter Mode (GCM) Cipher Suites for TLS", RFC 5288,
DOI 10.17487/RFC5288, August 2008,
.
[RFC5289] Rescorla, E., "TLS Elliptic Curve Cipher Suites with SHA-
256/384 and AES Galois Counter Mode (GCM)", RFC 5289,
DOI 10.17487/RFC5289, August 2008,
.
[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,
.
[RFC7589] Badra, M., Luchuk, A., and J. Schoenwaelder, "Using the
NETCONF Protocol over Transport Layer Security (TLS) with
Mutual X.509 Authentication", RFC 7589,
DOI 10.17487/RFC7589, June 2015,
.
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[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
.
8.2. Informative References
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818,
DOI 10.17487/RFC2818, May 2000,
.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
.
[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,
.
[RFC8071] Watsen, K., "NETCONF Call Home and RESTCONF Call Home",
RFC 8071, DOI 10.17487/RFC8071, February 2017,
.
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Appendix A. Change Log
A.1. server-model-09 to 00
o This draft was split out from draft-ietf-netconf-server-model-09.
o Noted that '0.0.0.0' and '::' might have special meanings.
A.2. 00 to 01
o Renamed "keychain" to "keystore".
A.3. 01 to 02
o Removed the groupings containing transport-level configuration.
Now modules contain only the transport-independent groupings.
o Filled in previously incomplete 'ietf-tls-client' module.
o Added cipher suites for various algorithms into new 'ietf-tls-
common' module.
Appendix B. Open Issues
Please see: https://github.com/netconf-wg/tls-client-server/issues.
Authors' Addresses
Kent Watsen
Juniper Networks
EMail: kwatsen@juniper.net
Gary Wu
Cisco Systems
EMail: garywu@cisco.com
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