Internet Engineering Task Force (IETF) R. Fielding, Editor Request for Comments: 7230 Adobe Obsoletes: 2145, 2616 J. Reschke, Editor Updates: 2817, 2818 greenbytes Category: Standards Track June 2014 ISSN: 2070-1721 Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing Abstract The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypertext information systems. This document provides an overview of HTTP architecture and its associated terminology, defines the "http" and "https" Uniform Resource Identifier (URI) schemes, defines the HTTP/1.1 message syntax and parsing requirements, and describes related security concerns for implementations. 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 57411. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc72302. Copyright Notice Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info3) 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. This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be 1 https://www.rfc-editor.org/rfc/rfc5741.html#section-2 2 http://www.rfc-editor.org/info/rfc7230 3 http://trustee.ietf.org/license-info RFC 7230 HTTP/1.1 Message Syntax and Routing June 2014 created outside the IETF Standards Process, except to format it for publication as an RFC or to translate it into languages other than English. Fielding & Reschke Standards Track [Page 2] RFC 7230 HTTP/1.1 Message Syntax and Routing June 2014 Table of Contents 1 Introduction...............................................................................................................................................................6 1.1 Requirements Notation.......................................................................................................................................... 6 1.2 Syntax Notation..................................................................................................................................................... 6 2 Architecture...............................................................................................................................................................8 2.1 Client/Server Messaging........................................................................................................................................8 2.2 Implementation Diversity...................................................................................................................................... 9 2.3 Intermediaries.........................................................................................................................................................9 2.4 Caches.................................................................................................................................................................. 10 2.5 Conformance and Error Handling.......................................................................................................................11 2.6 Protocol Versioning.............................................................................................................................................12 2.7 Uniform Resource Identifiers..............................................................................................................................13 2.7.1 http URI Scheme............................................................................................................................................ 14 2.7.2 https URI Scheme...........................................................................................................................................15 2.7.3 http and https URI Normalization and Comparison...................................................................................... 15 3 Message Format......................................................................................................................................................16 3.1 Start Line............................................................................................................................................................. 16 3.1.1 Request Line................................................................................................................................................... 16 3.1.2 Status Line...................................................................................................................................................... 17 3.2 Header Fields.......................................................................................................................................................17 3.2.1 Field Extensibility...........................................................................................................................................18 3.2.2 Field Order......................................................................................................................................................18 3.2.3 Whitespace...................................................................................................................................................... 18 3.2.4 Field Parsing................................................................................................................................................... 19 3.2.5 Field Limits.....................................................................................................................................................20 3.2.6 Field Value Components................................................................................................................................ 20 3.3 Message Body......................................................................................................................................................21 3.3.1 Transfer-Encoding.......................................................................................................................................... 21 3.3.2 Content-Length............................................................................................................................................... 22 3.3.3 Message Body Length....................................................................................................................................23 3.4 Handling Incomplete Messages...........................................................................................................................24 3.5 Message Parsing Robustness...............................................................................................................................24 4 Transfer Codings.................................................................................................................................................... 26 4.1 Chunked Transfer Coding................................................................................................................................... 26 4.1.1 Chunk Extensions........................................................................................................................................... 26 4.1.2 Chunked Trailer Part...................................................................................................................................... 27 4.1.3 Decoding Chunked......................................................................................................................................... 27 4.2 Compression Codings..........................................................................................................................................28 4.2.1 Compress Coding............................................................................................................................................28 4.2.2 Deflate Coding................................................................................................................................................28 4.2.3 Gzip Coding....................................................................................................................................................28 4.3 TE.........................................................................................................................................................................28