NETCONF Working Group K. Watsen Internet-Draft Watsen Networks Intended status: Standards Track 8 July 2020 Expires: 9 January 2021 YANG Groupings for HTTP Clients and HTTP Servers draft-ietf-netconf-http-client-server-04 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 * "BBBB" --> the assigned RFC value for draft-ietf-netconf-trust- anchors * "CCCC" --> the assigned RFC value for draft-ietf-netconf-keystore * "DDDD" --> the assigned RFC value for draft-ietf-netconf-tcp- client-server * "EEEE" --> the assigned RFC value for draft-ietf-netconf-ssh- client-server * "FFFF" --> the assigned RFC value for draft-ietf-netconf-tls- client-server * "GGGG" --> the assigned RFC value for this draft Watsen Expires 9 January 2021 [Page 1] Internet-Draft Groupings for HTTP Clients and Servers July 2020 Artwork in this document contains placeholder values for the date of publication of this draft. Please apply the following replacement: * "2020-07-08" --> the publication date of this draft The following Appendix section is to be removed prior to publication: * 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/. 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 9 January 2021. Copyright Notice Copyright (c) 2020 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 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. Relation to other RFCs . . . . . . . . . . . . . . . . . 3 1.2. Specification Language . . . . . . . . . . . . . . . . . 5 1.3. Adherence to the NMDA . . . . . . . . . . . . . . . . . . 5 2. The "ietf-http-client" Module . . . . . . . . . . . . . . . . 5 2.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 5 Watsen Expires 9 January 2021 [Page 2] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 4.2. The "ietf-http-server" YANG Module . . . . . . . . . . . 25 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25 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 . . . . . . . . . . . . . . . . . . . . . . . . 29 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 30 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 30 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 define configuration modules for 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 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. Links the each RFC are provided below the diagram. Watsen Expires 9 January 2021 [Page 3] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 Watsen Expires 9 January 2021 [Page 4] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 in 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 . 2. The "ietf-http-client" Module 2.1. Data Model Overview 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 2.1.2. Groupings The following diagram lists all the "grouping" statements defined in the "ietf-http-client" module: Groupings: +-- 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: Watsen Expires 9 January 2021 [Page 5] Internet-Draft Groupings for HTTP Clients and Servers July 2020 grouping http-client-identity-grouping +-- client-identity! +-- (auth-type) +--:(basic) +-- basic {basic-auth}? +-- user-id string +-- password string 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 that its descendent "choice" node's "mandatory true" doesn't imply that a client identity 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: 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 Watsen Expires 9 January 2021 [Page 6] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 that its descendent "choice" node's "mandatory true" doesn't imply that a proxy connection 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]. 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 Watsen Expires 9 January 2021 [Page 7] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 does not contain any protocol- accessible nodes. 2.2. Example Usage This section presents two examples showing the http-client-grouping populated with some data. The following example illustrates an HTTP client connecting directly to an HTTP server. bob secret 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]. Watsen Expires 9 January 2021 [Page 8] Internet-Draft Groupings for HTTP Clients and Servers July 2020 =============== NOTE: '\' line wrapping per RFC 8792 ================ bob secret corp-fw2.example.com 15 3 30 rsa-asymmetric-key ex-rsa-cert trusted-server-ca-certs trusted-server-ee-certs local-app-1 secret Watsen Expires 9 January 2021 [Page 9] Internet-Draft Groupings for HTTP Clients and Servers July 2020 2.3. YANG Module This YANG module has normative references to [RFC6991]. file "ietf-http-client@2020-07-08.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-tcp-client { prefix tcpc; reference "RFC AAAA: YANG Groupings for TCP Clients and TCP Servers"; } import ietf-tls-client { prefix tlsc; reference "RFC BBBB: YANG Groupings for TLS Clients and TLS Servers"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: Author: Kent Watsen "; description "This module defines reusable groupings for HTTP clients that can be used as a basis for specific HTTP client instances. Copyright (c) 2020 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with Watsen Expires 9 January 2021 [Page 10] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 (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 2020-07-08 { description "Initial version"; 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 Watsen Expires 9 January 2021 [Page 11] Internet-Draft Groupings for HTTP Clients and Servers July 2020 "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 HTTP-level client authentication is sent. Present so that the 'choice' node's mandatory true doesn't imply that a client identity must be configured."; description "The identity the HTTP client should use when authenticating itself to the HTTP server."; choice auth-type { mandatory true; 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."; } leaf password { nacm:default-deny-all; type string; mandatory true; description "The password for the authenticating client."; } description "The 'basic' HTTP scheme credentials."; reference "RFC 7617: The 'Basic' HTTP Authentication Scheme"; } } } } Watsen Expires 9 January 2021 [Page 12] Internet-Draft Groupings for HTTP Clients and Servers July 2020 } // 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 descendent 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. FIXME: it is assumed that the application can construct any necessary HTTP path, e.g., via a YANG 'rpc' definition...ok?"; uses http-client-identity-grouping; container proxy-connect { nacm:default-deny-write; if-feature "proxy-connect"; presence "Indicates that the HTTP-client is to connect thru an HTTP-level proxy server. Present so that the 'choice' node's mandatory true doesn't imply that a proxy connection must be configured."; choice proxy-type { mandatory true; description "Choice amongst proxy server types."; case http { container http-proxy { /* FIXME: THIS ISN'T NEEDED...because in a 'case' presence "Indicates that a HTTP proxy (Web proxy) connection is configured."; */ description "Container for HTTP Proxy (Web Proxy) server configuration parameters."; container tcp-client-parameters { Watsen Expires 9 January 2021 [Page 13] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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; /* FIXME: is HTTP Proxy auth *required* refine client-identity/auth-type { mandatory true; } */ } } } case https { container https-proxy { /* FIXME: THIS ISN'T NEEDED...because in a 'case' presence "Indicates that a HTTPS proxy (Secure web proxy) connection is configured."; */ /* FIXME: is HTTP Proxy auth *required* must "tls-client-parameters/client-identity or http-client-parameters/client-identity"; */ 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"; } container http-client-parameters { description "A wrapper around the HTTP parameters to avoid Watsen Expires 9 January 2021 [Page 14] Internet-Draft Groupings for HTTP Clients and Servers July 2020 name collisions."; uses http-client-identity-grouping; } } } } description "Proxy server settings."; } } // 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 { Watsen Expires 9 January 2021 [Page 15] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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"; } container http-client-parameters { description "A wrapper around the HTTP parameters to avoid name collisions."; uses http-client-grouping; } } } } } } // module ietf-http-client 3. The "ietf-http-server" Module 3.1. Data Model Overview 3.1.1. Features The following diagram lists all the "feature" statements defined in the "ietf-http-server" module: Features: +-- client-auth-config-supported +-- basic-auth +-- tcp-supported +-- tls-supported 3.1.2. Groupings The following diagram lists all the "grouping" statements defined in the "ietf-http-server" module: Watsen Expires 9 January 2021 [Page 16] Internet-Draft Groupings for HTTP Clients and Servers July 2020 Groupings: +-- 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-config-supported}? +-- users +-- 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, albiet it must be enabled by a "feature". Other authentication schemes MAY be augmented in. 3.1.2.2. The "http-server-stack-grouping" Grouping The following tree diagram [RFC8340] illustrates the "http-server- stack-grouping" grouping: Watsen Expires 9 January 2021 [Page 17] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 does not contain any protocol- accessible nodes. 3.2. Example Usage This section presents an example showing the http-server-grouping populated with some data. foo.example.com Watsen Expires 9 January 2021 [Page 18] Internet-Draft Groupings for HTTP Clients and Servers July 2020 3.3. YANG Module This YANG module has normative references to [RFC6991]. file "ietf-http-server@2020-07-08.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 AAAA: YANG Groupings for TCP Clients and TCP Servers"; } import ietf-tls-server { prefix tlss; reference "RFC BBBB: YANG Groupings for TLS Clients and TLS Servers"; } organization "IETF NETCONF (Network Configuration) Working Group"; contact "WG Web: WG List: Author: Kent Watsen "; description "This module defines reusable groupings for HTTP servers that can be used as a basis for specific HTTP server instances. Copyright (c) 2020 IETF Trust and the persons identified Watsen Expires 9 January 2021 [Page 19] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 (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 2020-07-08 { description "Initial version"; reference "RFC GGGG: YANG Groupings for HTTP Clients and HTTP Servers"; } // Features feature client-auth-config-supported { description "Indicates that the configuration for how to authenticate clients can be configured herein, as opposed to in an application specific location. That is, to support the consuming data models that prefer to place client authentication with client definitions, rather then in a data model principally concerned with configuring the transport."; } 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"; } Watsen Expires 9 January 2021 [Page 20] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 descendent 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-config-supported"; nacm:default-deny-write; presence "Indicates that HTTP based client authentication is supported (i.e., the server will request that the HTTP client send authenticate when needed). This is needed as some HTTP-based protocols may only support, e.g., TLS-level client authentication."; description "Specifies how the HTTP server can authenticate HTTP clients."; container users { description Watsen Expires 9 January 2021 [Page 21] Internet-Draft Groupings for HTTP Clients and Servers July 2020 "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 { description "The authentication type."; 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"; } } } } } // 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 Watsen Expires 9 January 2021 [Page 22] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 "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; } } } } } } Watsen Expires 9 January 2021 [Page 23] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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. | 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. Watsen Expires 9 January 2021 [Page 24] Internet-Draft Groupings for HTTP Clients and Servers July 2020 | 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. | 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 Watsen Expires 9 January 2021 [Page 25] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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 NETCONF WG of the IETF. XML: N/A, the requested URI is an XML namespace. URI: urn:ietf:params:xml:ns:yang:ietf-http-server Registrant Contact: The NETCONF WG of the IETF. 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 XXXX name: ietf-http-server namespace: urn:ietf:params:xml:ns:yang:ietf-http-server prefix: https reference: RFC XXXX 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013, . Watsen Expires 9 January 2021 [Page 26] Internet-Draft Groupings for HTTP Clients and Servers July 2020 [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . 6.2. Informative References [I-D.ietf-netconf-crypto-types] Watsen, K., "Common YANG Data Types for Cryptography", Work in Progress, Internet-Draft, draft-ietf-netconf- crypto-types-15, 20 May 2020, . [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-03, 20 May 2020, . [I-D.ietf-netconf-keystore] Watsen, K., "A YANG Data Model for a Keystore", Work in Progress, Internet-Draft, draft-ietf-netconf-keystore-17, 20 May 2020, . [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-19, 20 May 2020, . [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-19, 20 May 2020, . Watsen Expires 9 January 2021 [Page 27] Internet-Draft Groupings for HTTP Clients and Servers July 2020 [I-D.ietf-netconf-ssh-client-server] Watsen, K. and G. Wu, "YANG Groupings for SSH Clients and SSH Servers", Work in Progress, Internet-Draft, draft- ietf-netconf-ssh-client-server-19, 20 May 2020, . [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-06, 16 June 2020, . [I-D.ietf-netconf-tls-client-server] Watsen, K. and G. Wu, "YANG Groupings for TLS Clients and TLS Servers", Work in Progress, Internet-Draft, draft- ietf-netconf-tls-client-server-19, 20 May 2020, . [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-10, 20 May 2020, . [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, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [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, . Watsen Expires 9 January 2021 [Page 28] Internet-Draft Groupings for HTTP Clients and Servers July 2020 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. * 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. Watsen Expires 9 January 2021 [Page 29] Internet-Draft Groupings for HTTP Clients and Servers July 2020 * Expanded "Data Model Overview section(s) [remove "wall" of tree diagrams]. * Updated the Security Considerations section. Acknowledgements The authors would like to thank for following for lively discussions on list and in the halls (ordered by last name): Mark Nottingham, Ben Schwartz, and Willy Tarreau. Author's Address Kent Watsen Watsen Networks Email: kent+ietf@watsen.net Watsen Expires 9 January 2021 [Page 30]