YANG Groupings for HTTP Clients and HTTP Servers
draft-ietf-netconf-http-client-server-10
| Document | Type | Active Internet-Draft (netconf WG) | |
|---|---|---|---|
| Author | Kent Watsen | ||
| Last updated | 2022-07-18 (Latest revision 2022-05-24) | ||
| Replaces | draft-kwatsen-netconf-http-client-server | ||
| Stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | Proposed Standard | ||
| Formats | |||
| Yang Validation | 0 errors, 0 warnings | ||
| Reviews |
YANGDOCTORS Last Call review
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| Additional resources |
Yang catalog entry for ietf-http-client@2020-08-20.yang
Yang catalog entry for ietf-http-server@2020-08-20.yang Yang impact analysis for draft-ietf-netconf-http-client-server Mailing list discussion |
||
| Stream | WG state | WG Consensus: Waiting for Write-Up | |
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
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draft-ietf-netconf-http-client-server-10
NETCONF Working Group K. Watsen
Internet-Draft Watsen Networks
Intended status: Standards Track 24 May 2022
Expires: 25 November 2022
YANG Groupings for HTTP Clients and HTTP Servers
draft-ietf-netconf-http-client-server-10
Abstract
This document defines two YANG modules: the first defines a minimal
grouping for configuring an HTTP client, and the second defines a
minimal grouping for configuring an HTTP server. It is intended that
these groupings will be used to help define the configuration for
simple HTTP-based protocols (not for complete web servers or
browsers).
Editorial Note (To be removed by RFC Editor)
This draft contains 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 (note: not all may
be present):
* AAAA --> the assigned RFC value for draft-ietf-netconf-crypto-
types
* DDDD --> the assigned RFC value for draft-ietf-netconf-tcp-client-
server
* FFFF --> the assigned RFC value for draft-ietf-netconf-tls-client-
server
* GGGG --> 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:
* 2022-05-24 --> the publication date of this draft
The following Appendix section is to be removed prior to publication:
* Appendix A. Change Log
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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/.
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 25 November 2022.
Copyright Notice
Copyright (c) 2022 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 include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Relation to other RFCs . . . . . . . . . . . . . . . . . 3
1.2. Specification Language . . . . . . . . . . . . . . . . . 5
1.3. Adherence to the NMDA . . . . . . . . . . . . . . . . . . 5
1.4. Conventions . . . . . . . . . . . . . . . . . . . . . . . 5
2. The "ietf-http-client" Module . . . . . . . . . . . . . . . . 5
2.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 5
2.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 8
2.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 10
3. The "ietf-http-server" Module . . . . . . . . . . . . . . . . 16
3.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 16
3.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 18
3.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 19
4. Security Considerations . . . . . . . . . . . . . . . . . . . 24
4.1. The "ietf-http-client" YANG Module . . . . . . . . . . . 24
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4.2. The "ietf-http-server" YANG Module . . . . . . . . . . . 25
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26
5.1. The "IETF XML" Registry . . . . . . . . . . . . . . . . . 26
5.2. The "YANG Module Names" Registry . . . . . . . . . . . . 26
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
6.1. Normative References . . . . . . . . . . . . . . . . . . 26
6.2. Informative References . . . . . . . . . . . . . . . . . 27
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 29
A.1. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 29
A.2. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 29
A.3. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 29
A.4. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 30
A.5. 04 to 05 . . . . . . . . . . . . . . . . . . . . . . . . 30
A.6. 05 to 06 . . . . . . . . . . . . . . . . . . . . . . . . 30
A.7. 06 to 07 . . . . . . . . . . . . . . . . . . . . . . . . 30
A.8. 07 to 08 . . . . . . . . . . . . . . . . . . . . . . . . 31
A.9. 08 to 09 . . . . . . . . . . . . . . . . . . . . . . . . 31
A.10. 09 to 10 . . . . . . . . . . . . . . . . . . . . . . . . 31
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 31
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 31
1. Introduction
This document defines two YANG 1.1 [RFC7950] modules: the first
defines a minimal grouping for configuring an HTTP client, and the
second defines a minimal grouping for configuring an HTTP server. It
is intended that these groupings will be used to help define the
configuration for simple HTTP-based protocols (not for complete web
servers or browsers).
1.1. Relation to other RFCs
This document presents one or more YANG modules [RFC7950] that are
part of a collection of RFCs that work together to, ultimately,
enable the configuration of the clients and servers of both the
NETCONF [RFC6241] and RESTCONF [RFC8040] protocols.
The modules have been defined in a modular fashion to enable their
use by other efforts, some of which are known to be in progress at
the time of this writing, with many more expected to be defined in
time.
The normative dependency relationship between the various RFCs in the
collection is presented in the below diagram. The labels in the
diagram represent the primary purpose provided by each RFC.
Hyperlinks to each RFC are provided below the diagram.
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crypto-types
^ ^
/ \
/ \
truststore keystore
^ ^ ^ ^
| +---------+ | |
| | | |
| +------------+ |
tcp-client-server | / | |
^ ^ ssh-client-server | |
| | ^ tls-client-server
| | | ^ ^ http-client-server
| | | | | ^
| | | +-----+ +---------+ |
| | | | | |
| +-----------|--------|--------------+ | |
| | | | | |
+-----------+ | | | | |
| | | | | |
| | | | | |
netconf-client-server restconf-client-server
+=======================+===========================================+
|Label in Diagram | Originating RFC |
+=======================+===========================================+
|crypto-types | [I-D.ietf-netconf-crypto-types] |
+-----------------------+-------------------------------------------+
|truststore | [I-D.ietf-netconf-trust-anchors] |
+-----------------------+-------------------------------------------+
|keystore | [I-D.ietf-netconf-keystore] |
+-----------------------+-------------------------------------------+
|tcp-client-server | [I-D.ietf-netconf-tcp-client-server] |
+-----------------------+-------------------------------------------+
|ssh-client-server | [I-D.ietf-netconf-ssh-client-server] |
+-----------------------+-------------------------------------------+
|tls-client-server | [I-D.ietf-netconf-tls-client-server] |
+-----------------------+-------------------------------------------+
|http-client-server | [I-D.ietf-netconf-http-client-server] |
+-----------------------+-------------------------------------------+
|netconf-client-server | [I-D.ietf-netconf-netconf-client-server] |
+-----------------------+-------------------------------------------+
|restconf-client-server | [I-D.ietf-netconf-restconf-client-server] |
+-----------------------+-------------------------------------------+
Table 1: Label to RFC Mapping
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1.2. Specification 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
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
1.3. Adherence to the NMDA
This document is compliant with the Network Management Datastore
Architecture (NMDA) [RFC8342]. For instance, as described in
[I-D.ietf-netconf-trust-anchors] and [I-D.ietf-netconf-keystore],
trust anchors and keys installed during manufacturing are expected to
appear in <operational>.
1.4. Conventions
Various examples used in this document use a placeholder value for
binary data that has been base64 encoded (e.g., "BASE64VALUE=").
This placeholder value is used as real base64 encoded structures are
often many lines long and hence distracting to the example being
presented.
2. The "ietf-http-client" Module
This section defines a YANG 1.1 module called "ietf-http-client". A
high-level overview of the module is provided in Section 2.1.
Examples illustrating the module's use are provided in Examples
(Section 2.2). The YANG module itself is defined in Section 2.3.
2.1. Data Model Overview
This section provides an overview of the "ietf-http-client" module in
terms of its features and groupings.
2.1.1. Features
The following diagram lists all the "feature" statements defined in
the "ietf-http-client" module:
Features:
+-- proxy-connect
+-- basic-auth
+-- tcp-supported
+-- tls-supported
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| The diagram above uses syntax that is similar to but not
| defined in [RFC8340].
2.1.2. Groupings
The "ietf-http-client" module defines the following "grouping"
statements:
* http-client-identity-grouping
* http-client-grouping
* http-client-stack-grouping
Each of these groupings are presented in the following subsections.
2.1.2.1. The "http-client-identity-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "http-client-
identity-grouping" grouping:
grouping http-client-identity-grouping:
+-- client-identity!
+-- (auth-type)
+--:(basic)
+-- basic {basic-auth}?
+-- user-id string
+---u ct:password-grouping
Comments:
* This grouping exists because it is used three times by the "http-
client-grouping" discussed in Section 2.1.2.2.
* The "client-identity" node is a "presence" container so the
mandatory descendant nodes do not imply that this node must be
configured, as a client identity may be configured at protocol
layers.
* The "basic" authentication scheme is the only scheme defined by
this module, albeit it must be enabled via the "basic-auth"
feature (see Section 2.1.1).
* Other authentication schemes MAY be augmented in as needed by the
application.
2.1.2.2. The "http-client-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "http-client-
grouping" grouping:
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grouping http-client-grouping:
+---u http-client-identity-grouping
+-- proxy-connect! {proxy-connect}?
+-- (proxy-type)
+--:(http)
| +-- http-proxy
| +-- tcp-client-parameters
| | +---u tcpc:tcp-client-grouping
| +-- http-client-parameters
| +---u http-client-identity-grouping
+--:(https)
+-- https-proxy
+-- tcp-client-parameters
| +---u tcpc:tcp-client-grouping
+-- tls-client-parameters
| +---u tlsc:tls-client-grouping
+-- http-client-parameters
+---u http-client-identity-grouping
Comments:
* The "http-client-grouping" defines the configuration for just
"HTTP" part of a protocol stack. It does not, for instance,
define any configuration for the "TCP" or "TLS" protocol layers
(for that, see Section 2.1.2.3).
* Beyond configuring the client's identity, via the "http-client-
identity-grouping" grouping discussed in Section 2.1.2.1, this
grouping defines support for HTTP-proxies, albeit it must be
enabled via a "feature" statement.
* The "proxy-connect" node is a "presence" container so the
mandatory descendant nodes do not imply that this node must be
configured, assuming the server supports the "proxy-connect"
feature.
* For the referenced grouping statement(s):
- The "http-client-identity-grouping" grouping is discussed in
Section 2.1.2.1.
- The "tcp-client-grouping" grouping is discussed in
Section 3.1.2.1 of [I-D.ietf-netconf-tcp-client-server].
- The "tls-client-grouping" grouping is discussed in
Section 3.1.2.1 of [I-D.ietf-netconf-tls-client-server].
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2.1.2.3. The "http-client-stack-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "http-client-
stack-grouping" grouping:
grouping http-client-stack-grouping:
+-- (transport)
+--:(tcp) {tcp-supported}?
| +-- tcp
| +-- tcp-client-parameters
| | +---u tcpc:tcp-client-grouping
| +-- http-client-parameters
| +---u http-client-grouping
+--:(tls) {tls-supported}?
+-- tls
+-- tcp-client-parameters
| +---u tcpc:tcp-client-grouping
+-- tls-client-parameters
| +---u tlsc:tls-client-grouping
+-- http-client-parameters
+---u http-client-grouping
Comments:
* The "http-client-stack-grouping" is a convenience grouping for
downstream modules. It defines both the "HTTP" and "HTTPS"
protocol stacks, with each option enabled by a "feature" statement
for application control.
* For the referenced grouping statement(s):
- The "tcp-client-grouping" grouping is discussed in
Section 3.1.2.1 of [I-D.ietf-netconf-tcp-client-server].
- The "tls-client-grouping" grouping is discussed in
Section 3.1.2.1 of [I-D.ietf-netconf-tls-client-server].
- The "http-client-grouping" grouping is discussed in
Section 2.1.2.2 in this document.
2.1.3. Protocol-accessible Nodes
The "ietf-http-client" module defines only "grouping" statements that
are used by other modules to instantiate protocol-accessible nodes.
2.2. Example Usage
This section presents two examples showing the http-client-grouping
populated with some data.
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The following example illustrates an HTTP client connecting directly
to an HTTP server.
<!-- The outermost element below doesn't exist in the data model. -->
<!-- It simulates if the "grouping" were a "container" instead. -->
<http-client xmlns="urn:ietf:params:xml:ns:yang:ietf-http-client">
<client-identity>
<basic>
<user-id>bob</user-id>
<cleartext-password>secret</cleartext-password>
</basic>
</client-identity>
</http-client>
The following example illustrates the same client connecting through
an HTTP proxy. This example is consistent with examples presented in
Section 2.2 of [I-D.ietf-netconf-trust-anchors] and Section 2.2 of
[I-D.ietf-netconf-keystore].
=============== NOTE: '\' line wrapping per RFC 8792 ================
<!-- The outermost element below doesn't exist in the data model. -->
<!-- It simulates if the "grouping" were a "container" instead. -->
<http-client xmlns="urn:ietf:params:xml:ns:yang:ietf-http-client">
<client-identity>
<basic>
<user-id>bob</user-id>
<cleartext-password>secret</cleartext-password>
</basic>
</client-identity>
<proxy-connect>
<https-proxy>
<tcp-client-parameters>
<remote-address>corp-fw2.example.com</remote-address>
<keepalives>
<idle-time>15</idle-time>
<max-probes>3</max-probes>
<probe-interval>30</probe-interval>
</keepalives>
</tcp-client-parameters>
<tls-client-parameters>
<client-identity>
<certificate>
<keystore-reference>
<asymmetric-key>rsa-asymmetric-key</asymmetric-key>
<certificate>ex-rsa-cert</certificate>
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</keystore-reference>
</certificate>
</client-identity>
<server-authentication>
<ca-certs>
<truststore-reference>trusted-server-ca-certs</truststor\
e-reference>
</ca-certs>
<ee-certs>
<truststore-reference>trusted-server-ee-certs</truststor\
e-reference>
</ee-certs>
</server-authentication>
</tls-client-parameters>
<http-client-parameters>
<client-identity>
<basic>
<user-id>local-app-1</user-id>
<cleartext-password>secret</cleartext-password>
</basic>
</client-identity>
</http-client-parameters>
</https-proxy>
</proxy-connect>
</http-client>
2.3. YANG Module
This YANG module has normative references to [RFC6991].
<CODE BEGINS> file "ietf-http-client@2022-05-24.yang"
module ietf-http-client {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-http-client";
prefix httpc;
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
import ietf-crypto-types {
prefix ct;
reference
"RFC AAAA: YANG Data Types and Groupings for Cryptography";
}
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import ietf-tcp-client {
prefix tcpc;
reference
"RFC DDDD: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-tls-client {
prefix tlsc;
reference
"RFC FFFF: YANG Groupings for TLS Clients and TLS Servers";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: https://datatracker.ietf.org/wg/netconf
WG List: NETCONF WG list <mailto:netconf@ietf.org>
Author: Kent Watsen <mailto:kent+ietf@watsen.net>";
description
"This module defines reusable groupings for HTTP clients that
can be used as a basis for specific HTTP client instances.
Copyright (c) 2022 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 Revised
BSD License set forth in Section 4.c of the IETF Trust's
Legal Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC GGGG
(https://www.rfc-editor.org/info/rfcGGGG); see the RFC
itself for full legal notices.
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 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.";
revision 2022-05-24 {
description
"Initial version";
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reference
"RFC GGGG: YANG Groupings for HTTP Clients and HTTP Servers";
}
// Features
feature proxy-connect {
description
"Proxy connection configuration is configurable for
HTTP clients on the server implementing this feature.";
}
feature basic-auth {
description
"The 'basic-auth' feature indicates that the client
may be configured to use the 'basic' HTTP authentication
scheme.";
reference
"RFC 7617: The 'Basic' HTTP Authentication Scheme";
}
feature tcp-supported {
description
"Indicates that the server supports HTTP/TCP.";
}
feature tls-supported {
description
"Indicates that the server supports HTTP/TLS.";
}
// Groupings
grouping http-client-identity-grouping {
description
"A grouping to provide HTTP credentials used by the
client to authenticate itself to the HTTP server.";
container client-identity {
nacm:default-deny-write;
presence
"Indicates that a client identity has been configured.
This statement is present so the mandatory descendant
nodes do not imply that this node must be configured.";
description
"The identity the HTTP client should use when
authenticating itself to the HTTP server.";
choice auth-type {
mandatory true;
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description
"A choice amongst available authentication types.";
case basic {
container basic {
if-feature "basic-auth";
leaf user-id {
type string;
mandatory true;
description
"The user-id for the authenticating client.";
}
uses ct:password-grouping {
description
"The password for the authenticating client.";
}
description
"The 'basic' HTTP scheme credentials.";
reference
"RFC 7617: The 'Basic' HTTP Authentication Scheme";
}
}
}
}
} // grouping http-client-identity-grouping
grouping http-client-grouping {
description
"A reusable grouping for configuring a HTTP client.
This grouping is expected to be used in conjunction with
other configurations providing, e.g., the hostname or IP
address and port number the client initiates connections
to.
Note that this grouping uses fairly typical descendant
node names such that a stack of 'uses' statements will
have name conflicts. It is intended that the consuming
data model will resolve the issue (e.g., by wrapping
the 'uses' statement in a container called
'http-client-parameters'). This model purposely does
not do this itself so as to provide maximum flexibility
to consuming models.";
uses http-client-identity-grouping;
container proxy-connect {
nacm:default-deny-write;
if-feature "proxy-connect";
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presence
"Indicates that a proxy server connections have been
configured. This statement is present so the mandatory
descendant nodes do not imply that this node must be
configured.";
description
"Configures the proxy server the HTTP-client is to
connect thru.";
choice proxy-type {
mandatory true;
description
"Choice amongst proxy server types.";
case http {
container http-proxy {
description
"Container for HTTP Proxy (Web Proxy) server
configuration parameters.";
container tcp-client-parameters {
description
"A wrapper around the TCP parameters to avoid
name collisions.";
uses tcpc:tcp-client-grouping;
}
container http-client-parameters {
description
"A wrapper around the HTTP parameters to avoid
name collisions.";
uses http-client-identity-grouping;
}
}
}
case https {
container https-proxy {
description
"Container for HTTPS Proxy (Secure Web Proxy) server
configuration parameters.";
container tcp-client-parameters {
description
"A wrapper around the TCP parameters to avoid
name collisions.";
uses tcpc:tcp-client-grouping;
}
container tls-client-parameters {
description
"A wrapper around the TLS parameters to avoid
name collisions.";
uses tlsc:tls-client-grouping;
}
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container http-client-parameters {
description
"A wrapper around the HTTP parameters to avoid
name collisions.";
uses http-client-identity-grouping;
}
}
}
}
}
} // grouping http-client-grouping
grouping http-client-stack-grouping {
description
"A grouping that defines common HTTP-based protocol stacks.";
choice transport {
mandatory true;
description
"Choice amongst various transports type. TCP, with and
without TLS are defined here, with 'feature' statements
so that they may be disabled. Other transports MAY be
augmented in as 'case' statements by future efforts.";
case tcp {
if-feature "tcp-supported";
container tcp {
description
"Container for TCP-based HTTP protocols.";
container tcp-client-parameters {
description
"A wrapper around the TCP parameters to avoid
name collisions.";
uses tcpc:tcp-client-grouping;
}
container http-client-parameters {
description
"A wrapper around the HTTP parameters to avoid
name collisions.";
uses http-client-grouping;
}
}
}
case tls {
if-feature "tls-supported";
container tls {
description
"Container for TLS-based HTTP protocols.";
container tcp-client-parameters {
description
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"A wrapper around the TCP parameters to avoid
name collisions.";
uses tcpc:tcp-client-grouping;
}
container tls-client-parameters {
description
"A wrapper around the TLS parameters to avoid
name collisions.";
uses tlsc:tls-client-grouping;
}
container http-client-parameters {
description
"A wrapper around the HTTP parameters to avoid
name collisions.";
uses http-client-grouping;
}
}
}
}
} // http-client-stack-grouping
}
<CODE ENDS>
3. The "ietf-http-server" Module
This section defines a YANG 1.1 module called "ietf-http-server". A
high-level overview of the module is provided in Section 3.1.
Examples illustrating the module's use are provided in Examples
(Section 3.2). The YANG module itself is defined in Section 3.3.
3.1. Data Model Overview
This section provides an overview of the "ietf-http-server" module in
terms of its features and groupings.
3.1.1. Features
The following diagram lists all the "feature" statements defined in
the "ietf-http-server" module:
Features:
+-- client-auth-supported
+-- local-users-supported
+-- basic-auth
+-- tcp-supported
+-- tls-supported
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| The diagram above uses syntax that is similar to but not
| defined in [RFC8340].
3.1.2. Groupings
The "ietf-http-server" module defines the following "grouping"
statements:
* http-server-grouping
* http-server-stack-grouping
Each of these groupings are presented in the following subsections.
3.1.2.1. The "http-server-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "http-server-
grouping" grouping:
grouping http-server-grouping:
+-- server-name? string
+-- client-authentication! {client-auth-supported}?
+-- users {local-users-supported}?
+-- user* [user-id]
+-- user-id? string
+-- (auth-type)
+--:(basic)
+-- basic {basic-auth}?
+-- user-id? string
+-- password? ianach:crypt-hash
Comments:
* The "http-server-grouping" defines the configuration for just
"HTTP" part of a protocol stack. It does not, for instance,
define any configuration for the "TCP" or "TLS" protocol layers
(for that, see Section 3.1.2.2).
* The "server-name" node defines the HTTP server's name, as
presented to HTTP clients.
* The "client-authentication" node, which must by enabled by a
feature, defines a very simple user-database. Only the "basic"
authentication scheme is supported, albeit it must be enabled by a
"feature". Other authentication schemes MAY be augmented in.
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3.1.2.2. The "http-server-stack-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "http-server-
stack-grouping" grouping:
grouping http-server-stack-grouping:
+-- (transport)
+--:(tcp) {tcp-supported}?
| +-- tcp
| +-- tcp-server-parameters
| | +---u tcps:tcp-server-grouping
| +-- http-server-parameters
| +---u http-server-grouping
+--:(tls) {tls-supported}?
+-- tls
+-- tcp-server-parameters
| +---u tcps:tcp-server-grouping
+-- tls-server-parameters
| +---u tlss:tls-server-grouping
+-- http-server-parameters
+---u http-server-grouping
Comments:
* The "http-server-stack-grouping" is a convenience grouping for
downstream modules. It defines both the "HTTP" and "HTTPS"
protocol stacks, with each option enabled by a "feature" statement
for application control.
* For the referenced grouping statement(s):
- The "tcp-server-grouping" grouping is discussed in
Section 4.1.2.1 of [I-D.ietf-netconf-tcp-client-server].
- The "tls-server-grouping" grouping is discussed in
Section 4.1.2.1 of [I-D.ietf-netconf-tls-client-server].
- The "http-server-grouping" grouping is discussed in
Section 3.1.2.1 in this document.
3.1.3. Protocol-accessible Nodes
The "ietf-http-server" module defines only "grouping" statements that
are used by other modules to instantiate protocol-accessible nodes.
3.2. Example Usage
This section presents an example showing the http-server-grouping
populated with some data.
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<!-- The outermost element below doesn't exist in the data model. -->
<!-- It simulates if the "grouping" were a "container" instead. -->
<http-server xmlns="urn:ietf:params:xml:ns:yang:ietf-http-server">
<server-name>foo.example.com</server-name>
</http-server>
3.3. YANG Module
This YANG module has normative references to [RFC6991].
<CODE BEGINS> file "ietf-http-server@2022-05-24.yang"
module ietf-http-server {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-http-server";
prefix https;
import iana-crypt-hash {
prefix ianach;
reference
"RFC 7317: A YANG Data Model for System Management";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
import ietf-tcp-server {
prefix tcps;
reference
"RFC DDDD: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-tls-server {
prefix tlss;
reference
"RFC FFFF: YANG Groupings for TLS Clients and TLS Servers";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: https://datatracker.ietf.org/wg/netconf
WG List: NETCONF WG list <mailto:netconf@ietf.org>
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Author: Kent Watsen <mailto:kent+ietf@watsen.net>";
description
"This module defines reusable groupings for HTTP servers that
can be used as a basis for specific HTTP server instances.
Copyright (c) 2022 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 Revised
BSD License set forth in Section 4.c of the IETF Trust's
Legal Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC GGGG
(https://www.rfc-editor.org/info/rfcGGGG); see the RFC
itself for full legal notices.
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 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.";
revision 2022-05-24 {
description
"Initial version";
reference
"RFC GGGG: YANG Groupings for HTTP Clients and HTTP Servers";
}
// Features
feature client-auth-supported {
description
"Indicates that the configuration for how to authenticate
clients can be configured herein. HTTP-level client
authentication may not be needed when client authentication
is expected to occur only at another protocol layer.";
}
feature local-users-supported {
description
"Indicates that the configuration for users can be
configured herein, as opposed to in an application
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specific location.";
}
feature basic-auth {
description
"The 'basic-auth' feature indicates that the server
may be configured authenticate users using the 'basic'
HTTP authentication scheme.";
reference
"RFC 7617: The 'Basic' HTTP Authentication Scheme";
}
feature tcp-supported {
description
"Indicates that the server supports HTTP/TCP.";
}
feature tls-supported {
description
"Indicates that the server supports HTTP/TLS.";
}
// Groupings
grouping http-server-grouping {
description
"A reusable grouping for configuring an HTTP server.
Note that this grouping uses fairly typical descendant
node names such that a stack of 'uses' statements will
have name conflicts. It is intended that the consuming
data model will resolve the issue (e.g., by wrapping
the 'uses' statement in a container called
'http-server-parameters'). This model purposely does
not do this itself so as to provide maximum flexibility
to consuming models.";
leaf server-name {
nacm:default-deny-write;
type string;
description
"The value of the 'Server' header field. If not set, then
underlying software's default value is used. Set to the
empty string to disable.";
}
container client-authentication {
if-feature "client-auth-supported";
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nacm:default-deny-write;
presence
"Indicates that HTTP based client authentication is
configured. This statement is present so the mandatory
descendant nodes do not imply that this node must be
configured.";
description
"Configures how the HTTP server can authenticate HTTP
clients. The HTTP server will request that the HTTP
client send authentication when needed.";
container users {
if-feature "local-users-supported";
description
"A list of locally configured users.";
list user {
key "user-id";
description
"The list of local users configured on this device.";
leaf user-id {
type string;
description
"The user-id for the authenticating client.";
}
choice auth-type {
mandatory true;
description
"The authentication type.";
case basic {
container basic {
if-feature "basic-auth";
leaf user-id {
type string;
description
"The user-id for the authenticating client.";
}
leaf password {
nacm:default-deny-write;
type ianach:crypt-hash;
description
"The password for the authenticating client.";
}
description
"The 'basic' HTTP scheme credentials.";
reference
"RFC 7617:
The 'Basic' HTTP Authentication Scheme";
}
}
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}
}
}
} // container client-authentication
} // grouping http-server-grouping
grouping http-server-stack-grouping {
description
"A grouping that defines common HTTP-based protocol stacks.";
choice transport {
mandatory true;
description
"Choice amongst various transports type. TCP, with and
without TLS are defined here, with 'feature' statements
so that they may be disabled. Other transports MAY be
augmented in as 'case' statements by future efforts.";
case tcp {
if-feature "tcp-supported";
container tcp {
description
"Container for TCP-based HTTP protocols.";
container tcp-server-parameters {
description
"A wrapper around the TCP parameters to avoid
name collisions.";
uses tcps:tcp-server-grouping;
}
container http-server-parameters {
description
"A wrapper around the HTTP parameters to avoid
name collisions.";
uses http-server-grouping;
}
}
}
case tls {
if-feature "tls-supported";
container tls {
description
"Container for TLS-based HTTP protocols.";
container tcp-server-parameters {
description
"A wrapper around the TCP parameters to avoid
name collisions.";
uses tcps:tcp-server-grouping;
}
container tls-server-parameters {
description
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"A wrapper around the TLS parameters to avoid
name collisions.";
uses tlss:tls-server-grouping;
}
container http-server-parameters {
description
"A wrapper around the HTTP parameters to avoid
name collisions.";
uses http-server-grouping;
}
}
}
}
} // http-server-stack-grouping
}
<CODE ENDS>
4. Security Considerations
4.1. The "ietf-http-client" YANG Module
The "ietf-http-client" YANG module defines "grouping" statements that
are 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) [RFC8341] provides the means
to restrict access for particular users to a pre-configured subset of
all available protocol operations and content.
Since the module in this document only define groupings, these
considerations are primarily for the designers of other modules that
use these groupings.
One readable data node defined in this YANG module may be considered
sensitive or vulnerable in some network environments. This node is
as follows:
* The "client-identity/basic/password" node:
The cleartext "password" node defined in the "http-client-
identity-grouping" grouping is additionally sensitive to read
operations such that, in normal use cases, it should never be
returned to a client. For this reason, the NACM extension
"default-deny-all" has been applied to it.
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| Please be aware that this module uses the "key" and "private-
| key" nodes from the "ietf-crypto-types" module
| [I-D.ietf-netconf-crypto-types], where said nodes have the NACM
| extension "default-deny-all" set, thus preventing unrestricted
| read-access to the cleartext key values.
None of the writable data nodes defined in this YANG module are
considered sensitive or vulnerable in network environments. The NACM
"default-deny-write" extension has not been set for any data nodes
defined in this module.
| Please be aware that this module uses groupings from the "ietf-
| tls-client" and "ietf-tls-server" modules defined in
| [I-D.ietf-netconf-tls-client-server]. All of the data nodes
| defined in these groupings have the NACM extension "default-
| deny-write" set, thus preventing unrestricted write-access to
| the data nodes defined in those groupings.
This module does not define any RPCs, actions, or notifications, and
thus the security consideration for such is not provided here.
4.2. The "ietf-http-server" YANG Module
The "ietf-http-server" YANG module defines "grouping" statements that
are 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) [RFC8341] provides the means
to restrict access for particular users to a pre-configured subset of
all available protocol operations and content.
Since the module in this document only define groupings, these
considerations are primarily for the designers of other modules that
use these groupings.
None of the readable data nodes defined in this YANG module are
considered sensitive or vulnerable in network environments. The NACM
"default-deny-all" extension has not been set for any data nodes
defined in this module.
None of the writable data nodes defined in this YANG module are
considered sensitive or vulnerable in network environments. The NACM
"default-deny-write" extension has not been set for any data nodes
defined in this module.
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| Please be aware that this module uses groupings from the "ietf-
| tls-client" and "ietf-tls-server" modules defined in
| [I-D.ietf-netconf-tls-client-server]. All of the data nodes
| defined in these groupings have the NACM extension "default-
| deny-write" set, thus preventing unrestricted write-access to
| the data nodes defined in those groupings.
This module does not define any RPCs, actions, or notifications, and
thus the security consideration for such is not provided here.
5. IANA Considerations
5.1. The "IETF XML" Registry
This document registers two URIs in the "ns" subregistry of the IETF
XML Registry [RFC3688]. Following the format in [RFC3688], the
following registrations are requested:
URI: urn:ietf:params:xml:ns:yang:ietf-http-client
Registrant Contact: The IESG
XML: N/A, the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-http-server
Registrant Contact: The IESG
XML: N/A, the requested URI is an XML namespace.
5.2. The "YANG Module Names" Registry
This document registers two YANG modules in the YANG Module Names
registry [RFC6020]. Following the format in [RFC6020], the following
registrations are requested:
name: ietf-http-client
namespace: urn:ietf:params:xml:ns:yang:ietf-http-client
prefix: httpc
reference: RFC GGGG
name: ietf-http-server
namespace: urn:ietf:params:xml:ns:yang:ietf-http-server
prefix: https
reference: RFC GGGG
6. References
6.1. Normative References
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[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
6.2. Informative References
[I-D.ietf-netconf-crypto-types]
Watsen, K., "YANG Data Types and Groupings for
Cryptography", Work in Progress, Internet-Draft, draft-
ietf-netconf-crypto-types-22, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
crypto-types-22>.
[I-D.ietf-netconf-http-client-server]
Watsen, K., "YANG Groupings for HTTP Clients and HTTP
Servers", Work in Progress, Internet-Draft, draft-ietf-
netconf-http-client-server-09, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
http-client-server-09>.
[I-D.ietf-netconf-keystore]
Watsen, K., "A YANG Data Model for a Keystore", Work in
Progress, Internet-Draft, draft-ietf-netconf-keystore-24,
7 March 2022, <https://datatracker.ietf.org/doc/html/
draft-ietf-netconf-keystore-24>.
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[I-D.ietf-netconf-netconf-client-server]
Watsen, K., "NETCONF Client and Server Models", Work in
Progress, Internet-Draft, draft-ietf-netconf-netconf-
client-server-25, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
netconf-client-server-25>.
[I-D.ietf-netconf-restconf-client-server]
Watsen, K., "RESTCONF Client and Server Models", Work in
Progress, Internet-Draft, draft-ietf-netconf-restconf-
client-server-25, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
restconf-client-server-25>.
[I-D.ietf-netconf-ssh-client-server]
Watsen, K., "YANG Groupings for SSH Clients and SSH
Servers", Work in Progress, Internet-Draft, draft-ietf-
netconf-ssh-client-server-27, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
ssh-client-server-27>.
[I-D.ietf-netconf-tcp-client-server]
Watsen, K. and M. Scharf, "YANG Groupings for TCP Clients
and TCP Servers", Work in Progress, Internet-Draft, draft-
ietf-netconf-tcp-client-server-12, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
tcp-client-server-12>.
[I-D.ietf-netconf-tls-client-server]
Watsen, K., "YANG Groupings for TLS Clients and TLS
Servers", Work in Progress, Internet-Draft, draft-ietf-
netconf-tls-client-server-27, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
tls-client-server-27>.
[I-D.ietf-netconf-trust-anchors]
Watsen, K., "A YANG Data Model for a Truststore", Work in
Progress, Internet-Draft, draft-ietf-netconf-trust-
anchors-17, 7 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
trust-anchors-17>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
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[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,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
Appendix A. Change Log
This section is to be removed before publishing as an RFC.
A.1. 00 to 01
* Modified Abstract and Intro to be more accurate wrt intended
applicability.
* In ietf-http-client, removed "protocol-version" and all auth
schemes except "basic".
* In ietf-http-client, factored out "client-identity-grouping" for
proxy connections.
* In ietf-http-server, removed "choice required-or-optional" and
"choice local-or-external".
* In ietf-http-server, moved the basic auth under a "choice auth-
type" limited by new "feature basic-auth".
A.2. 01 to 02
* Removed the unused "external-client-auth-supported" feature from
ietf-http-server.
A.3. 02 to 03
* Removed "protocol-versions" from ietf-http-server based on HTTP WG
feedback.
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* Slightly restructured the "proxy-server" definition in ietf-http-
client.
* Added http-client example show proxy server use.
* Added a "Note to Reviewers" note to first page.
A.4. 03 to 04
* Added a parent "container" to "client-identity-grouping" so that
it could be better used by the proxy model.
* Added a "choice" to the proxy model enabling selection of proxy
types.
* Added 'http-client-stack-grouping' and 'http-server-stack-
grouping' convenience groupings.
* Expanded "Data Model Overview section(s) [remove "wall" of tree
diagrams].
* Updated the Security Considerations section.
A.5. 04 to 05
* Fixed titles and a ref in the IANA Considerations section
* Cleaned up examples (e.g., removed FIXMEs)
* Fixed issues found by the SecDir review of the "keystore" draft.
* Updated the "ietf-http-client" module to use the new "password-
grouping" grouping from the "crypto-types" module.
A.6. 05 to 06
* Removed note questioning if okay for app to augment-in a 'path'
node when needed, discussed during the 108 session.
* Addressed comments raised by YANG Doctor in the ct/ts/ks drafts.
A.7. 06 to 07
* Added XML-comment above examples explaining the reason for the
unusual top-most element's presence.
* Renamed 'client-auth-config-supported' to 'client-auth-supported'
consistent with other drafts.
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* Wrapped 'container basic' choice inside a 'case basic' per best
practice.
* Aligned modules with `pyang -f` formatting.
* Fixed nits found by YANG Doctor reviews.
A.8. 07 to 08
* Replaced "base64encodedvalue==" with "BASE64VALUE=" in examples.
* Minor editorial nits
A.9. 08 to 09
* Fixed up the 'WG Web' and 'WG List' lines in YANG module(s)
* Fixed up copyright (i.e., s/Simplified/Revised/) in YANG module(s)
A.10. 09 to 10
* NO UPDATE.
Acknowledgements
The authors would like to thank for following for lively discussions
on list and in the halls (ordered by first name): Ben Schwartz, Mark
Nottingham, Rob Wilton (contributor), and Willy Tarreau.
Author's Address
Kent Watsen
Watsen Networks
Email: kent+ietf@watsen.net
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