Internet Engineering Task Force (IETF)                       R. Hamilton
Request for Comments: 9220                                        Google
Category: Standards Track                                    June 2022
ISSN: 2070-1721


                  Bootstrapping WebSockets with HTTP/3

 Abstract

   The mechanism for running the WebSocket Protocol over a single stream
   of an HTTP/2 connection is equally applicable to HTTP/3, but the
   HTTP-version-specific details need to be specified.  This document
   describes how the mechanism is adapted for HTTP/3.

 Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/RFC 9220.

 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
   2.  Conventions and Definitions
   3.  WebSockets Upgrade over HTTP/3
   4.  Security Considerations
   5.  IANA Considerations
   6.  Normative References
   Acknowledgments
   Author's Address

1.  Introduction

   "Bootstrapping WebSockets with HTTP/2" [RFC 8441] defines an extension
   to HTTP/2 [HTTP/2] that is also useful in HTTP/3 [HTTP/3].  This
   extension makes use of an HTTP/2 setting.  Appendix A.3 of [HTTP/3]
   gives some guidance on what changes (if any) are appropriate when
   porting settings from HTTP/2 to HTTP/3.

2.  Conventions and Definitions

   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.

3.  WebSockets Upgrade over HTTP/3

   [RFC 8441] defines a mechanism for running the WebSocket Protocol
   [RFC 6455] over a single stream of an HTTP/2 connection.  It defines
   an Extended CONNECT method that specifies a new ":protocol" pseudo-
   header field and new semantics for the ":path" and ":authority"
   pseudo-header fields.  It also defines a new HTTP/2 setting sent by a
   server to allow the client to use Extended CONNECT.

   The semantics of the pseudo-header fields and setting are identical
   to those in HTTP/2 as defined in [RFC 8441].  Appendix A.3 of [HTTP/3]
   requires that HTTP/3 settings be registered separately for HTTP/3.
   The SETTINGS_ENABLE_CONNECT_PROTOCOL value is 0x08 (decimal 8), as in
   HTTP/2.

   If a server advertises support for Extended CONNECT but receives an
   Extended CONNECT request with a ":protocol" value that is unknown or
   is not supported, the server SHOULD respond to the request with a 501
   (Not Implemented) status code (Section 15.6.2 of [HTTP]).  A server
   MAY provide more information via a "problem details" response
   [RFC 7807].

   The HTTP/3 stream closure is also analogous to the TCP connection
   closure of [RFC 6455].  Orderly TCP-level closures are represented as
   a FIN bit on the stream (Section 4.4 of [HTTP/3]).  RST exceptions
   are represented with a stream error (Section 8 of [HTTP/3]) of type
   H3_REQUEST_CANCELLED (Section 8.1 of [HTTP/3]).

4.  Security Considerations

   This document introduces no new security considerations beyond those
   discussed in [RFC 8441].

5.  IANA Considerations

   This document registers a new setting in the "HTTP/3 Settings"
   registry (Section 11.2.2 of [HTTP/3]).

   Value:  0x08
   Setting Name:  SETTINGS_ENABLE_CONNECT_PROTOCOL
   Default:  0
   Status:  permanent
   Specification:  This document
   Change Controller:  IETF
   Contact:  HTTP Working Group (ietf-http-wg@w3.org)

6.  Normative References

   [HTTP]     Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke,
              Ed., "HTTP Semantics", STD 97, RFC 9110,
              DOI 10.17487/RFC 9110, June 2022,
              <https://www.rfc-editor.org/info/RFC 9110>.

   [HTTP/2]   Thomson, M., Ed. and C. Benfield, Ed., "HTTP/2", RFC 9113,
              DOI 10.17487/RFC 9113, June 2022,
              <https://www.rfc-editor.org/info/RFC 9113>.

   [HTTP/3]   Bishop, M., Ed., "HTTP/3", RFC 9114, DOI 10.17487/RFC 9114,
              June 2022, <https://www.rfc-editor.org/info/RFC 9114>.

   [RFC 2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC 2119, March 1997,
              <https://www.rfc-editor.org/info/RFC 2119>.

   [RFC 6455]  Fette, I. and A. Melnikov, "The WebSocket Protocol",
              RFC 6455, DOI 10.17487/RFC 6455, December 2011,
              <https://www.rfc-editor.org/info/RFC 6455>.

   [RFC 7807]  Nottingham, M. and E. Wilde, "Problem Details for HTTP
              APIs", RFC 7807, DOI 10.17487/RFC 7807, March 2016,
              <https://www.rfc-editor.org/info/RFC 7807>.

   [RFC 8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC 8174,
              May 2017, <https://www.rfc-editor.org/info/RFC 8174>.

   [RFC 8441]  McManus, P., "Bootstrapping WebSockets with HTTP/2",
              RFC 8441, DOI 10.17487/RFC 8441, September 2018,
              <https://www.rfc-editor.org/info/RFC 8441>.

Acknowledgments

   This document had reviews and input from many contributors in the
   IETF HTTP and QUIC Working Groups, with substantive input from David
   Schinazi, Martin Thomson, Lucas Pardue, Mike Bishop, Dragana
   Damjanovic, Mark Nottingham, and Julian Reschke.

Author's Address

   Ryan Hamilton
   Google
   Email: rch@google.com



RFC TOTAL SIZE: 6619 bytes
PUBLICATION DATE: Thursday, June 9th, 2022
LEGAL RIGHTS: The IETF Trust (see BCP 78)