| draft-ietf-httpbis-messaging-11.txt | draft-ietf-httpbis-messaging-12.txt | |||
|---|---|---|---|---|
| HTTP Working Group R. Fielding, Ed. | HTTP Working Group R. Fielding, Ed. | |||
| Internet-Draft Adobe | Internet-Draft Adobe | |||
| Obsoletes: 7230 (if approved) M. Nottingham, Ed. | Obsoletes: 7230 (if approved) M. Nottingham, Ed. | |||
| Intended status: Standards Track Fastly | Intended status: Standards Track Fastly | |||
| Expires: February 28, 2021 J. F. Reschke, Ed. | Expires: April 5, 2021 J. Reschke, Ed. | |||
| greenbytes | greenbytes | |||
| August 27, 2020 | October 2, 2020 | |||
| HTTP/1.1 Messaging | HTTP/1.1 Messaging | |||
| draft-ietf-httpbis-messaging-11 | draft-ietf-httpbis-messaging-12 | |||
| Abstract | Abstract | |||
| The Hypertext Transfer Protocol (HTTP) is a stateless application- | The Hypertext Transfer Protocol (HTTP) is a stateless application- | |||
| level protocol for distributed, collaborative, hypertext information | level protocol for distributed, collaborative, hypertext information | |||
| systems. This document specifies the HTTP/1.1 message syntax, | systems. This document specifies the HTTP/1.1 message syntax, | |||
| message parsing, connection management, and related security | message parsing, connection management, and related security | |||
| concerns. | concerns. | |||
| This document obsoletes portions of RFC 7230. | This document obsoletes portions of RFC 7230. | |||
| skipping to change at page 1, line 36 ¶ | skipping to change at page 1, line 36 ¶ | |||
| This note is to be removed before publishing as an RFC. | This note is to be removed before publishing as an RFC. | |||
| Discussion of this draft takes place on the HTTP working group | Discussion of this draft takes place on the HTTP working group | |||
| mailing list (ietf-http-wg@w3.org), which is archived at | mailing list (ietf-http-wg@w3.org), which is archived at | |||
| <https://lists.w3.org/Archives/Public/ietf-http-wg/>. | <https://lists.w3.org/Archives/Public/ietf-http-wg/>. | |||
| Working Group information can be found at <https://httpwg.org/>; | Working Group information can be found at <https://httpwg.org/>; | |||
| source code and issues list for this draft can be found at | source code and issues list for this draft can be found at | |||
| <https://github.com/httpwg/http-core>. | <https://github.com/httpwg/http-core>. | |||
| The changes in this draft are summarized in Appendix D.12. | The changes in this draft are summarized in Appendix D.13. | |||
| Status of This Memo | Status of This Memo | |||
| This Internet-Draft is submitted in full conformance with the | This Internet-Draft is submitted in full conformance with the | |||
| provisions of BCP 78 and BCP 79. | provisions of BCP 78 and BCP 79. | |||
| Internet-Drafts are working documents of the Internet Engineering | Internet-Drafts are working documents of the Internet Engineering | |||
| Task Force (IETF). Note that other groups may also distribute | Task Force (IETF). Note that other groups may also distribute | |||
| working documents as Internet-Drafts. The list of current Internet- | working documents as Internet-Drafts. The list of current Internet- | |||
| Drafts is at https://datatracker.ietf.org/drafts/current/. | Drafts is at https://datatracker.ietf.org/drafts/current/. | |||
| Internet-Drafts are draft documents valid for a maximum of six months | Internet-Drafts are draft documents valid for a maximum of six months | |||
| and may be updated, replaced, or obsoleted by other documents at any | and may be updated, replaced, or obsoleted by other documents at any | |||
| time. It is inappropriate to use Internet-Drafts as reference | time. It is inappropriate to use Internet-Drafts as reference | |||
| material or to cite them other than as "work in progress." | material or to cite them other than as "work in progress." | |||
| This Internet-Draft will expire on February 28, 2021. | This Internet-Draft will expire on April 5, 2021. | |||
| Copyright Notice | Copyright Notice | |||
| Copyright (c) 2020 IETF Trust and the persons identified as the | Copyright (c) 2020 IETF Trust and the persons identified as the | |||
| document authors. All rights reserved. | document authors. All rights reserved. | |||
| This document is subject to BCP 78 and the IETF Trust's Legal | This document is subject to BCP 78 and the IETF Trust's Legal | |||
| Provisions Relating to IETF Documents (https://trustee.ietf.org/ | Provisions Relating to IETF Documents (https://trustee.ietf.org/ | |||
| license-info) in effect on the date of publication of this document. | license-info) in effect on the date of publication of this document. | |||
| Please review these documents carefully, as they describe your rights | Please review these documents carefully, as they describe your rights | |||
| skipping to change at page 3, line 46 ¶ | skipping to change at page 3, line 46 ¶ | |||
| 10.2. Media Type application/http . . . . . . . . . . . . . . 36 | 10.2. Media Type application/http . . . . . . . . . . . . . . 36 | |||
| 11. Security Considerations . . . . . . . . . . . . . . . . . . . 37 | 11. Security Considerations . . . . . . . . . . . . . . . . . . . 37 | |||
| 11.1. Response Splitting . . . . . . . . . . . . . . . . . . . 37 | 11.1. Response Splitting . . . . . . . . . . . . . . . . . . . 37 | |||
| 11.2. Request Smuggling . . . . . . . . . . . . . . . . . . . 38 | 11.2. Request Smuggling . . . . . . . . . . . . . . . . . . . 38 | |||
| 11.3. Message Integrity . . . . . . . . . . . . . . . . . . . 38 | 11.3. Message Integrity . . . . . . . . . . . . . . . . . . . 38 | |||
| 11.4. Message Confidentiality . . . . . . . . . . . . . . . . 39 | 11.4. Message Confidentiality . . . . . . . . . . . . . . . . 39 | |||
| 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 39 | 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 39 | |||
| 12.1. Field Name Registration . . . . . . . . . . . . . . . . 39 | 12.1. Field Name Registration . . . . . . . . . . . . . . . . 39 | |||
| 12.2. Media Type Registration . . . . . . . . . . . . . . . . 39 | 12.2. Media Type Registration . . . . . . . . . . . . . . . . 39 | |||
| 12.3. Transfer Coding Registration . . . . . . . . . . . . . . 40 | 12.3. Transfer Coding Registration . . . . . . . . . . . . . . 40 | |||
| 12.4. Upgrade Token Registration . . . . . . . . . . . . . . . 40 | 12.4. ALPN Protocol ID Registration . . . . . . . . . . . . . 40 | |||
| 12.5. ALPN Protocol ID Registration . . . . . . . . . . . . . 40 | ||||
| 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 40 | 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 40 | |||
| 13.1. Normative References . . . . . . . . . . . . . . . . . . 40 | 13.1. Normative References . . . . . . . . . . . . . . . . . . 40 | |||
| 13.2. Informative References . . . . . . . . . . . . . . . . . 41 | 13.2. Informative References . . . . . . . . . . . . . . . . . 41 | |||
| Appendix A. Collected ABNF . . . . . . . . . . . . . . . . . . . 43 | Appendix A. Collected ABNF . . . . . . . . . . . . . . . . . . . 43 | |||
| Appendix B. Differences between HTTP and MIME . . . . . . . . . 44 | Appendix B. Differences between HTTP and MIME . . . . . . . . . 44 | |||
| B.1. MIME-Version . . . . . . . . . . . . . . . . . . . . . . 45 | B.1. MIME-Version . . . . . . . . . . . . . . . . . . . . . . 45 | |||
| B.2. Conversion to Canonical Form . . . . . . . . . . . . . . 45 | B.2. Conversion to Canonical Form . . . . . . . . . . . . . . 45 | |||
| B.3. Conversion of Date Formats . . . . . . . . . . . . . . . 45 | B.3. Conversion of Date Formats . . . . . . . . . . . . . . . 45 | |||
| B.4. Conversion of Content-Encoding . . . . . . . . . . . . . 46 | B.4. Conversion of Content-Encoding . . . . . . . . . . . . . 46 | |||
| B.5. Conversion of Content-Transfer-Encoding . . . . . . . . . 46 | B.5. Conversion of Content-Transfer-Encoding . . . . . . . . . 46 | |||
| skipping to change at page 4, line 30 ¶ | skipping to change at page 4, line 29 ¶ | |||
| D.3. Since draft-ietf-httpbis-messaging-01 . . . . . . . . . . 50 | D.3. Since draft-ietf-httpbis-messaging-01 . . . . . . . . . . 50 | |||
| D.4. Since draft-ietf-httpbis-messaging-02 . . . . . . . . . . 51 | D.4. Since draft-ietf-httpbis-messaging-02 . . . . . . . . . . 51 | |||
| D.5. Since draft-ietf-httpbis-messaging-03 . . . . . . . . . . 51 | D.5. Since draft-ietf-httpbis-messaging-03 . . . . . . . . . . 51 | |||
| D.6. Since draft-ietf-httpbis-messaging-04 . . . . . . . . . . 51 | D.6. Since draft-ietf-httpbis-messaging-04 . . . . . . . . . . 51 | |||
| D.7. Since draft-ietf-httpbis-messaging-05 . . . . . . . . . . 52 | D.7. Since draft-ietf-httpbis-messaging-05 . . . . . . . . . . 52 | |||
| D.8. Since draft-ietf-httpbis-messaging-06 . . . . . . . . . . 52 | D.8. Since draft-ietf-httpbis-messaging-06 . . . . . . . . . . 52 | |||
| D.9. Since draft-ietf-httpbis-messaging-07 . . . . . . . . . . 52 | D.9. Since draft-ietf-httpbis-messaging-07 . . . . . . . . . . 52 | |||
| D.10. Since draft-ietf-httpbis-messaging-08 . . . . . . . . . . 53 | D.10. Since draft-ietf-httpbis-messaging-08 . . . . . . . . . . 53 | |||
| D.11. Since draft-ietf-httpbis-messaging-09 . . . . . . . . . . 53 | D.11. Since draft-ietf-httpbis-messaging-09 . . . . . . . . . . 53 | |||
| D.12. Since draft-ietf-httpbis-messaging-10 . . . . . . . . . . 53 | D.12. Since draft-ietf-httpbis-messaging-10 . . . . . . . . . . 53 | |||
| Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 53 | D.13. Since draft-ietf-httpbis-messaging-11 . . . . . . . . . . 53 | |||
| Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 54 | ||||
| Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 54 | Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 54 | |||
| 1. Introduction | 1. Introduction | |||
| The Hypertext Transfer Protocol (HTTP) is a stateless application- | The Hypertext Transfer Protocol (HTTP) is a stateless application- | |||
| level request/response protocol that uses extensible semantics and | level request/response protocol that uses extensible semantics and | |||
| self-descriptive messages for flexible interaction with network-based | self-descriptive messages for flexible interaction with network-based | |||
| hypertext information systems. HTTP is defined by a series of | hypertext information systems. HTTP is defined by a series of | |||
| documents that collectively form the HTTP/1.1 specification: | documents that collectively form the HTTP/1.1 specification: | |||
| skipping to change at page 5, line 25 ¶ | skipping to change at page 5, line 25 ¶ | |||
| 1.1. Requirements Notation | 1.1. Requirements Notation | |||
| The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | |||
| "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and | "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and | |||
| "OPTIONAL" in this document are to be interpreted as described in BCP | "OPTIONAL" in this document are to be interpreted as described in BCP | |||
| 14 [RFC2119] [RFC8174] when, and only when, they appear in all | 14 [RFC2119] [RFC8174] when, and only when, they appear in all | |||
| capitals, as shown here. | capitals, as shown here. | |||
| Conformance criteria and considerations regarding error handling are | Conformance criteria and considerations regarding error handling are | |||
| defined in Section 3 of [Semantics]. | defined in Section 2 of [Semantics]. | |||
| 1.2. Syntax Notation | 1.2. Syntax Notation | |||
| This specification uses the Augmented Backus-Naur Form (ABNF) | This specification uses the Augmented Backus-Naur Form (ABNF) | |||
| notation of [RFC5234], extended with the notation for case- | notation of [RFC5234], extended with the notation for case- | |||
| sensitivity in strings defined in [RFC7405]. | sensitivity in strings defined in [RFC7405]. | |||
| It also uses a list extension, defined in Section 5.5 of [Semantics], | It also uses a list extension, defined in Section 5.7.1 of | |||
| that allows for compact definition of comma-separated lists using a | [Semantics], that allows for compact definition of comma-separated | |||
| '#' operator (similar to how the '*' operator indicates repetition). | lists using a '#' operator (similar to how the '*' operator indicates | |||
| Appendix A shows the collected grammar with all list operators | repetition). Appendix A shows the collected grammar with all list | |||
| expanded to standard ABNF notation. | operators expanded to standard ABNF notation. | |||
| As a convention, ABNF rule names prefixed with "obs-" denote | As a convention, ABNF rule names prefixed with "obs-" denote | |||
| "obsolete" grammar rules that appear for historical reasons. | "obsolete" grammar rules that appear for historical reasons. | |||
| The following core rules are included by reference, as defined in | The following core rules are included by reference, as defined in | |||
| [RFC5234], Appendix B.1: ALPHA (letters), CR (carriage return), CRLF | [RFC5234], Appendix B.1: ALPHA (letters), CR (carriage return), CRLF | |||
| (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double quote), | (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double quote), | |||
| HEXDIG (hexadecimal 0-9/A-F/a-f), HTAB (horizontal tab), LF (line | HEXDIG (hexadecimal 0-9/A-F/a-f), HTAB (horizontal tab), LF (line | |||
| feed), OCTET (any 8-bit sequence of data), SP (space), and VCHAR (any | feed), OCTET (any 8-bit sequence of data), SP (space), and VCHAR (any | |||
| visible [USASCII] character). | visible [USASCII] character). | |||
| The rules below are defined in [Semantics]: | The rules below are defined in [Semantics]: | |||
| BWS = <BWS, see [Semantics], Section 1.6.1> | BWS = <BWS, see [Semantics], Section 5.7.3> | |||
| OWS = <OWS, see [Semantics], Section 1.6.1> | OWS = <OWS, see [Semantics], Section 5.7.3> | |||
| RWS = <RWS, see [Semantics], Section 1.6.1> | RWS = <RWS, see [Semantics], Section 5.7.3> | |||
| absolute-URI = <absolute-URI, see [RFC3986], Section 4.3> | absolute-URI = <absolute-URI, see [RFC3986], Section 4.3> | |||
| absolute-path = <absolute-path, see [Semantics], Section 2.4> | absolute-path = <absolute-path, see [Semantics], Section 4> | |||
| authority = <authority, see [RFC3986], Section 3.2> | authority = <authority, see [RFC3986], Section 3.2> | |||
| comment = <comment, see [Semantics], Section 5.4.1.3> | comment = <comment, see [Semantics], Section 5.7.5> | |||
| field-name = <field-name, see [Semantics], Section 5.3> | field-name = <field-name, see [Semantics], Section 5.4.3> | |||
| field-value = <field-value, see [Semantics], Section 5.4> | field-value = <field-value, see [Semantics], Section 5.4.4> | |||
| obs-text = <obs-text, see [Semantics], Section 5.4.1.2> | obs-text = <obs-text, see [Semantics], Section 5.7.4> | |||
| port = <port, see [RFC3986], Section 3.2.3> | port = <port, see [RFC3986], Section 3.2.3> | |||
| query = <query, see [RFC3986], Section 3.4> | query = <query, see [RFC3986], Section 3.4> | |||
| quoted-string = <quoted-string, see [Semantics], Section 5.4.1.2> | quoted-string = <quoted-string, see [Semantics], Section 5.7.4> | |||
| token = <token, see [Semantics], Section 5.4.1.1> | token = <token, see [Semantics], Section 5.7.2> | |||
| uri-host = <host, see [RFC3986], Section 3.2.2> | uri-host = <host, see [RFC3986], Section 3.2.2> | |||
| 2. Message | 2. Message | |||
| 2.1. Message Format | 2.1. Message Format | |||
| An HTTP/1.1 message consists of a start-line followed by a CRLF and a | An HTTP/1.1 message consists of a start-line followed by a CRLF and a | |||
| sequence of octets in a format similar to the Internet Message Format | sequence of octets in a format similar to the Internet Message Format | |||
| [RFC5322]: zero or more header field lines (collectively referred to | [RFC5322]: zero or more header field lines (collectively referred to | |||
| as the "headers" or the "header section"), an empty line indicating | as the "headers" or the "header section"), an empty line indicating | |||
| skipping to change at page 8, line 31 ¶ | skipping to change at page 8, line 31 ¶ | |||
| When a server listening only for HTTP request messages, or processing | When a server listening only for HTTP request messages, or processing | |||
| what appears from the start-line to be an HTTP request message, | what appears from the start-line to be an HTTP request message, | |||
| receives a sequence of octets that does not match the HTTP-message | receives a sequence of octets that does not match the HTTP-message | |||
| grammar aside from the robustness exceptions listed above, the server | grammar aside from the robustness exceptions listed above, the server | |||
| SHOULD respond with a 400 (Bad Request) response. | SHOULD respond with a 400 (Bad Request) response. | |||
| 2.3. HTTP Version | 2.3. HTTP Version | |||
| HTTP uses a "<major>.<minor>" numbering scheme to indicate versions | HTTP uses a "<major>.<minor>" numbering scheme to indicate versions | |||
| of the protocol. This specification defines version "1.1". | of the protocol. This specification defines version "1.1". | |||
| Section 4.2 of [Semantics] specifies the semantics of HTTP version | Section 5.1 of [Semantics] specifies the semantics of HTTP version | |||
| numbers. | numbers. | |||
| The version of an HTTP/1.x message is indicated by an HTTP-version | The version of an HTTP/1.x message is indicated by an HTTP-version | |||
| field in the start-line. HTTP-version is case-sensitive. | field in the start-line. HTTP-version is case-sensitive. | |||
| HTTP-version = HTTP-name "/" DIGIT "." DIGIT | HTTP-version = HTTP-name "/" DIGIT "." DIGIT | |||
| HTTP-name = %s"HTTP" | HTTP-name = %s"HTTP" | |||
| When an HTTP/1.1 message is sent to an HTTP/1.0 recipient [RFC1945] | When an HTTP/1.1 message is sent to an HTTP/1.0 recipient [RFC1945] | |||
| or a recipient whose version is unknown, the HTTP/1.1 message is | or a recipient whose version is unknown, the HTTP/1.1 message is | |||
| skipping to change at page 9, line 42 ¶ | skipping to change at page 9, line 42 ¶ | |||
| instead parse on whitespace-delimited word boundaries and, aside from | instead parse on whitespace-delimited word boundaries and, aside from | |||
| the CRLF terminator, treat any form of whitespace as the SP separator | the CRLF terminator, treat any form of whitespace as the SP separator | |||
| while ignoring preceding or trailing whitespace; such whitespace | while ignoring preceding or trailing whitespace; such whitespace | |||
| includes one or more of the following octets: SP, HTAB, VT (%x0B), FF | includes one or more of the following octets: SP, HTAB, VT (%x0B), FF | |||
| (%x0C), or bare CR. However, lenient parsing can result in request | (%x0C), or bare CR. However, lenient parsing can result in request | |||
| smuggling security vulnerabilities if there are multiple recipients | smuggling security vulnerabilities if there are multiple recipients | |||
| of the message and each has its own unique interpretation of | of the message and each has its own unique interpretation of | |||
| robustness (see Section 11.2). | robustness (see Section 11.2). | |||
| HTTP does not place a predefined limit on the length of a request- | HTTP does not place a predefined limit on the length of a request- | |||
| line, as described in Section 3 of [Semantics]. A server that | line, as described in Section 2 of [Semantics]. A server that | |||
| receives a method longer than any that it implements SHOULD respond | receives a method longer than any that it implements SHOULD respond | |||
| with a 501 (Not Implemented) status code. A server that receives a | with a 501 (Not Implemented) status code. A server that receives a | |||
| request-target longer than any URI it wishes to parse MUST respond | request-target longer than any URI it wishes to parse MUST respond | |||
| with a 414 (URI Too Long) status code (see Section 10.5.15 of | with a 414 (URI Too Long) status code (see Section 14.5.15 of | |||
| [Semantics]). | [Semantics]). | |||
| Various ad hoc limitations on request-line length are found in | Various ad hoc limitations on request-line length are found in | |||
| practice. It is RECOMMENDED that all HTTP senders and recipients | practice. It is RECOMMENDED that all HTTP senders and recipients | |||
| support, at a minimum, request-line lengths of 8000 octets. | support, at a minimum, request-line lengths of 8000 octets. | |||
| 3.1. Method | 3.1. Method | |||
| The method token indicates the request method to be performed on the | The method token indicates the request method to be performed on the | |||
| target resource. The request method is case-sensitive. | target resource. The request method is case-sensitive. | |||
| skipping to change at page 10, line 45 ¶ | skipping to change at page 10, line 45 ¶ | |||
| 400 (Bad Request) error or a 301 (Moved Permanently) redirect with | 400 (Bad Request) error or a 301 (Moved Permanently) redirect with | |||
| the request-target properly encoded. A recipient SHOULD NOT attempt | the request-target properly encoded. A recipient SHOULD NOT attempt | |||
| to autocorrect and then process the request without a redirect, since | to autocorrect and then process the request without a redirect, since | |||
| the invalid request-line might be deliberately crafted to bypass | the invalid request-line might be deliberately crafted to bypass | |||
| security filters along the request chain. | security filters along the request chain. | |||
| A client MUST send a Host header field in all HTTP/1.1 request | A client MUST send a Host header field in all HTTP/1.1 request | |||
| messages. If the target URI includes an authority component, then a | messages. If the target URI includes an authority component, then a | |||
| client MUST send a field value for Host that is identical to that | client MUST send a field value for Host that is identical to that | |||
| authority component, excluding any userinfo subcomponent and its "@" | authority component, excluding any userinfo subcomponent and its "@" | |||
| delimiter (Section 2.5.1 of [Semantics]). If the authority component | delimiter (Section 4.2.1 of [Semantics]). If the authority component | |||
| is missing or undefined for the target URI, then a client MUST send a | is missing or undefined for the target URI, then a client MUST send a | |||
| Host header field with an empty field value. | Host header field with an empty field value. | |||
| A server MUST respond with a 400 (Bad Request) status code to any | A server MUST respond with a 400 (Bad Request) status code to any | |||
| HTTP/1.1 request message that lacks a Host header field and to any | HTTP/1.1 request message that lacks a Host header field and to any | |||
| request message that contains more than one Host header field or a | request message that contains more than one Host header field or a | |||
| Host header field with an invalid field value. | Host header field with an invalid field value. | |||
| 3.2.1. origin-form | 3.2.1. origin-form | |||
| The most common form of request-target is the origin-form. | The most common form of request-target is the origin-form. | |||
| origin-form = absolute-path [ "?" query ] | origin-form = absolute-path [ "?" query ] | |||
| When making a request directly to an origin server, other than a | When making a request directly to an origin server, other than a | |||
| CONNECT or server-wide OPTIONS request (as detailed below), a client | CONNECT or server-wide OPTIONS request (as detailed below), a client | |||
| MUST send only the absolute path and query components of the target | MUST send only the absolute path and query components of the target | |||
| URI as the request-target. If the target URI's path component is | URI as the request-target. If the target URI's path component is | |||
| empty, the client MUST send "/" as the path within the origin-form of | empty, the client MUST send "/" as the path within the origin-form of | |||
| request-target. A Host header field is also sent, as defined in | request-target. A Host header field is also sent, as defined in | |||
| Section 6.5 of [Semantics]. | Section 6.1.2 of [Semantics]. | |||
| For example, a client wishing to retrieve a representation of the | For example, a client wishing to retrieve a representation of the | |||
| resource identified as | resource identified as | |||
| http://www.example.org/where?q=now | http://www.example.org/where?q=now | |||
| directly from the origin server would open (or reuse) a TCP | directly from the origin server would open (or reuse) a TCP | |||
| connection to port 80 of the host "www.example.org" and send the | connection to port 80 of the host "www.example.org" and send the | |||
| lines: | lines: | |||
| skipping to change at page 11, line 45 ¶ | skipping to change at page 11, line 45 ¶ | |||
| When making a request to a proxy, other than a CONNECT or server-wide | When making a request to a proxy, other than a CONNECT or server-wide | |||
| OPTIONS request (as detailed below), a client MUST send the target | OPTIONS request (as detailed below), a client MUST send the target | |||
| URI in absolute-form as the request-target. | URI in absolute-form as the request-target. | |||
| absolute-form = absolute-URI | absolute-form = absolute-URI | |||
| The proxy is requested to either service that request from a valid | The proxy is requested to either service that request from a valid | |||
| cache, if possible, or make the same request on the client's behalf | cache, if possible, or make the same request on the client's behalf | |||
| to either the next inbound proxy server or directly to the origin | to either the next inbound proxy server or directly to the origin | |||
| server indicated by the request-target. Requirements on such | server indicated by the request-target. Requirements on such | |||
| "forwarding" of messages are defined in Section 6.6 of [Semantics]. | "forwarding" of messages are defined in Section 6.4 of [Semantics]. | |||
| An example absolute-form of request-line would be: | An example absolute-form of request-line would be: | |||
| GET http://www.example.org/pub/WWW/TheProject.html HTTP/1.1 | GET http://www.example.org/pub/WWW/TheProject.html HTTP/1.1 | |||
| A client MUST send a Host header field in an HTTP/1.1 request even if | A client MUST send a Host header field in an HTTP/1.1 request even if | |||
| the request-target is in the absolute-form, since this allows the | the request-target is in the absolute-form, since this allows the | |||
| Host information to be forwarded through ancient HTTP/1.0 proxies | Host information to be forwarded through ancient HTTP/1.0 proxies | |||
| that might not have implemented Host. | that might not have implemented Host. | |||
| skipping to change at page 15, line 13 ¶ | skipping to change at page 15, line 13 ¶ | |||
| includes one or more of the following octets: SP, HTAB, VT (%x0B), FF | includes one or more of the following octets: SP, HTAB, VT (%x0B), FF | |||
| (%x0C), or bare CR. However, lenient parsing can result in response | (%x0C), or bare CR. However, lenient parsing can result in response | |||
| splitting security vulnerabilities if there are multiple recipients | splitting security vulnerabilities if there are multiple recipients | |||
| of the message and each has its own unique interpretation of | of the message and each has its own unique interpretation of | |||
| robustness (see Section 11.1). | robustness (see Section 11.1). | |||
| The status-code element is a 3-digit integer code describing the | The status-code element is a 3-digit integer code describing the | |||
| result of the server's attempt to understand and satisfy the client's | result of the server's attempt to understand and satisfy the client's | |||
| corresponding request. The rest of the response message is to be | corresponding request. The rest of the response message is to be | |||
| interpreted in light of the semantics defined for that status code. | interpreted in light of the semantics defined for that status code. | |||
| See Section 10 of [Semantics] for information about the semantics of | See Section 14 of [Semantics] for information about the semantics of | |||
| status codes, including the classes of status code (indicated by the | status codes, including the classes of status code (indicated by the | |||
| first digit), the status codes defined by this specification, | first digit), the status codes defined by this specification, | |||
| considerations for the definition of new status codes, and the IANA | considerations for the definition of new status codes, and the IANA | |||
| registry. | registry. | |||
| status-code = 3DIGIT | status-code = 3DIGIT | |||
| The reason-phrase element exists for the sole purpose of providing a | The reason-phrase element exists for the sole purpose of providing a | |||
| textual description associated with the numeric status code, mostly | textual description associated with the numeric status code, mostly | |||
| out of deference to earlier Internet application protocols that were | out of deference to earlier Internet application protocols that were | |||
| skipping to change at page 15, line 45 ¶ | skipping to change at page 15, line 45 ¶ | |||
| 5. Field Syntax | 5. Field Syntax | |||
| Each field line consists of a case-insensitive field name followed by | Each field line consists of a case-insensitive field name followed by | |||
| a colon (":"), optional leading whitespace, the field line value, and | a colon (":"), optional leading whitespace, the field line value, and | |||
| optional trailing whitespace. | optional trailing whitespace. | |||
| field-line = field-name ":" OWS field-value OWS | field-line = field-name ":" OWS field-value OWS | |||
| Most HTTP field names and the rules for parsing within field values | Most HTTP field names and the rules for parsing within field values | |||
| are defined in Section 5 of [Semantics]. This section covers the | are defined in Section 5.4 of [Semantics]. This section covers the | |||
| generic syntax for header field inclusion within, and extraction | generic syntax for header field inclusion within, and extraction | |||
| from, HTTP/1.1 messages. In addition, the following header fields | from, HTTP/1.1 messages. In addition, the following header fields | |||
| are defined by this document because they are specific to HTTP/1.1 | are defined by this document because they are specific to HTTP/1.1 | |||
| message processing: | message processing: | |||
| ------------------- ---------- ------ | ------------------- ---------- ------ | |||
| Field Name Status Ref. | Field Name Status Ref. | |||
| ------------------- ---------- ------ | ------------------- ---------- ------ | |||
| MIME-Version standard B.1 | MIME-Version standard B.1 | |||
| Transfer-Encoding standard 6.1 | Transfer-Encoding standard 6.1 | |||
| ------------------- ---------- ------ | ------------------- ---------- ------ | |||
| Table 1 | Table 1 | |||
| Furthermore, the field name "Close" is reserved, since using that | Furthermore, the field name "Close" is reserved, since using that | |||
| name as an HTTP header field might conflict with the "close" | name as an HTTP header field might conflict with the "close" | |||
| connection option of the Connection header field (Section 6.8 of | connection option of the Connection header field (Section 6.4.1 of | |||
| [Semantics]). | [Semantics]). | |||
| ------------ ---------- ----------- ------------ | ------------ ---------- ----------- ------------ | |||
| Field Name Status Reference Comments | Field Name Status Reference Comments | |||
| ------------ ---------- ----------- ------------ | ------------ ---------- ----------- ------------ | |||
| Close standard Section 5 (reserved) | Close standard Section 5 (reserved) | |||
| ------------ ---------- ----------- ------------ | ------------ ---------- ----------- ------------ | |||
| Table 2 | Table 2 | |||
| skipping to change at page 17, line 44 ¶ | skipping to change at page 17, line 44 ¶ | |||
| message downstream. | message downstream. | |||
| A user agent that receives an obs-fold in a response message that is | A user agent that receives an obs-fold in a response message that is | |||
| not within a message/http container MUST replace each received | not within a message/http container MUST replace each received | |||
| obs-fold with one or more SP octets prior to interpreting the field | obs-fold with one or more SP octets prior to interpreting the field | |||
| value. | value. | |||
| 6. Message Body | 6. Message Body | |||
| The message body (if any) of an HTTP message is used to carry the | The message body (if any) of an HTTP message is used to carry the | |||
| payload body (Section 7.3.3 of [Semantics]) of that request or | payload body (Section 5.5.4 of [Semantics]) of that request or | |||
| response. The message body is identical to the payload body unless a | response. The message body is identical to the payload body unless a | |||
| transfer coding has been applied, as described in Section 6.1. | transfer coding has been applied, as described in Section 6.1. | |||
| message-body = *OCTET | message-body = *OCTET | |||
| The rules for determining when a message body is present in an | The rules for determining when a message body is present in an | |||
| HTTP/1.1 message differ for requests and responses. | HTTP/1.1 message differ for requests and responses. | |||
| The presence of a message body in a request is signaled by a | The presence of a message body in a request is signaled by a | |||
| Content-Length or Transfer-Encoding header field. Request message | Content-Length or Transfer-Encoding header field. Request message | |||
| framing is independent of method semantics, even if the method does | framing is independent of method semantics, even if the method does | |||
| not define any use for a message body. | not define any use for a message body. | |||
| The presence of a message body in a response depends on both the | The presence of a message body in a response depends on both the | |||
| request method to which it is responding and the response status code | request method to which it is responding and the response status code | |||
| (Section 4), and corresponds to when a payload body is allowed; see | (Section 4), and corresponds to when a payload body is allowed; see | |||
| Section 7.3.3 of [Semantics]. | Section 5.5.4 of [Semantics]. | |||
| 6.1. Transfer-Encoding | 6.1. Transfer-Encoding | |||
| The Transfer-Encoding header field lists the transfer coding names | The Transfer-Encoding header field lists the transfer coding names | |||
| corresponding to the sequence of transfer codings that have been (or | corresponding to the sequence of transfer codings that have been (or | |||
| will be) applied to the payload body in order to form the message | will be) applied to the payload body in order to form the message | |||
| body. Transfer codings are defined in Section 7. | body. Transfer codings are defined in Section 7. | |||
| Transfer-Encoding = #transfer-coding | Transfer-Encoding = #transfer-coding | |||
| skipping to change at page 19, line 5 ¶ | skipping to change at page 19, line 5 ¶ | |||
| by closing the connection. | by closing the connection. | |||
| For example, | For example, | |||
| Transfer-Encoding: gzip, chunked | Transfer-Encoding: gzip, chunked | |||
| indicates that the payload body has been compressed using the gzip | indicates that the payload body has been compressed using the gzip | |||
| coding and then chunked using the chunked coding while forming the | coding and then chunked using the chunked coding while forming the | |||
| message body. | message body. | |||
| Unlike Content-Encoding (Section 7.1.2 of [Semantics]), Transfer- | Unlike Content-Encoding (Section 7.5.1 of [Semantics]), Transfer- | |||
| Encoding is a property of the message, not of the representation, and | Encoding is a property of the message, not of the representation, and | |||
| any recipient along the request/response chain MAY decode the | any recipient along the request/response chain MAY decode the | |||
| received transfer coding(s) or apply additional transfer coding(s) to | received transfer coding(s) or apply additional transfer coding(s) to | |||
| the message body, assuming that corresponding changes are made to the | the message body, assuming that corresponding changes are made to the | |||
| Transfer-Encoding field value. Additional information about the | Transfer-Encoding field value. Additional information about the | |||
| encoding parameters can be provided by other header fields not | encoding parameters can be provided by other header fields not | |||
| defined by this specification. | defined by this specification. | |||
| Transfer-Encoding MAY be sent in a response to a HEAD request or in a | Transfer-Encoding MAY be sent in a response to a HEAD request or in a | |||
| 304 (Not Modified) response (Section 10.4.5 of [Semantics]) to a GET | 304 (Not Modified) response (Section 14.4.5 of [Semantics]) to a GET | |||
| request, neither of which includes a message body, to indicate that | request, neither of which includes a message body, to indicate that | |||
| the origin server would have applied a transfer coding to the message | the origin server would have applied a transfer coding to the message | |||
| body if the request had been an unconditional GET. This indication | body if the request had been an unconditional GET. This indication | |||
| is not required, however, because any recipient on the response chain | is not required, however, because any recipient on the response chain | |||
| (including the origin server) can remove transfer codings when they | (including the origin server) can remove transfer codings when they | |||
| are not needed. | are not needed. | |||
| A server MUST NOT send a Transfer-Encoding header field in any | A server MUST NOT send a Transfer-Encoding header field in any | |||
| response with a status code of 1xx (Informational) or 204 (No | response with a status code of 1xx (Informational) or 204 (No | |||
| Content). A server MUST NOT send a Transfer-Encoding header field in | Content). A server MUST NOT send a Transfer-Encoding header field in | |||
| skipping to change at page 19, line 51 ¶ | skipping to change at page 19, line 51 ¶ | |||
| 6.2. Content-Length | 6.2. Content-Length | |||
| When a message does not have a Transfer-Encoding header field, a | When a message does not have a Transfer-Encoding header field, a | |||
| Content-Length header field can provide the anticipated size, as a | Content-Length header field can provide the anticipated size, as a | |||
| decimal number of octets, for a potential payload body. For messages | decimal number of octets, for a potential payload body. For messages | |||
| that do include a payload body, the Content-Length field value | that do include a payload body, the Content-Length field value | |||
| provides the framing information necessary for determining where the | provides the framing information necessary for determining where the | |||
| body (and message) ends. For messages that do not include a payload | body (and message) ends. For messages that do not include a payload | |||
| body, the Content-Length indicates the size of the selected | body, the Content-Length indicates the size of the selected | |||
| representation (Section 7.2.4 of [Semantics]). | representation (Section 7.7 of [Semantics]). | |||
| | *Note:* HTTP's use of Content-Length for message framing | | *Note:* HTTP's use of Content-Length for message framing | |||
| | differs significantly from the same field's use in MIME, where | | differs significantly from the same field's use in MIME, where | |||
| | it is an optional field used only within the "message/external- | | it is an optional field used only within the "message/external- | |||
| | body" media-type. | | body" media-type. | |||
| 6.3. Message Body Length | 6.3. Message Body Length | |||
| The length of a message body is determined by one of the following | The length of a message body is determined by one of the following | |||
| (in order of precedence): | (in order of precedence): | |||
| skipping to change at page 21, line 4 ¶ | skipping to change at page 21, line 4 ¶ | |||
| Content-Length. Such a message might indicate an attempt to | Content-Length. Such a message might indicate an attempt to | |||
| perform request smuggling (Section 11.2) or response splitting | perform request smuggling (Section 11.2) or response splitting | |||
| (Section 11.1) and ought to be handled as an error. A sender | (Section 11.1) and ought to be handled as an error. A sender | |||
| MUST remove the received Content-Length field prior to forwarding | MUST remove the received Content-Length field prior to forwarding | |||
| such a message downstream. | such a message downstream. | |||
| 4. If a message is received without Transfer-Encoding and with an | 4. If a message is received without Transfer-Encoding and with an | |||
| invalid Content-Length header field, then the message framing is | invalid Content-Length header field, then the message framing is | |||
| invalid and the recipient MUST treat it as an unrecoverable | invalid and the recipient MUST treat it as an unrecoverable | |||
| error, unless the field value can be successfully parsed as a | error, unless the field value can be successfully parsed as a | |||
| comma-separated list (Section 5.5 of [Semantics]), all values in | comma-separated list (Section 5.7.1 of [Semantics]), all values | |||
| the list are valid, and all values in the list are the same. If | in the list are valid, and all values in the list are the same. | |||
| this is a request message, the server MUST respond with a 400 | If this is a request message, the server MUST respond with a 400 | |||
| (Bad Request) status code and then close the connection. If this | (Bad Request) status code and then close the connection. If this | |||
| is a response message received by a proxy, the proxy MUST close | is a response message received by a proxy, the proxy MUST close | |||
| the connection to the server, discard the received response, and | the connection to the server, discard the received response, and | |||
| send a 502 (Bad Gateway) response to the client. If this is a | send a 502 (Bad Gateway) response to the client. If this is a | |||
| response message received by a user agent, the user agent MUST | response message received by a user agent, the user agent MUST | |||
| close the connection to the server and discard the received | close the connection to the server and discard the received | |||
| response. | response. | |||
| 5. If a valid Content-Length header field is present without | 5. If a valid Content-Length header field is present without | |||
| Transfer-Encoding, its decimal value defines the expected message | Transfer-Encoding, its decimal value defines the expected message | |||
| skipping to change at page 22, line 48 ¶ | skipping to change at page 22, line 48 ¶ | |||
| that is being transferred. | that is being transferred. | |||
| transfer-coding = token *( OWS ";" OWS transfer-parameter ) | transfer-coding = token *( OWS ";" OWS transfer-parameter ) | |||
| Parameters are in the form of a name=value pair. | Parameters are in the form of a name=value pair. | |||
| transfer-parameter = token BWS "=" BWS ( token / quoted-string ) | transfer-parameter = token BWS "=" BWS ( token / quoted-string ) | |||
| All transfer-coding names are case-insensitive and ought to be | All transfer-coding names are case-insensitive and ought to be | |||
| registered within the HTTP Transfer Coding registry, as defined in | registered within the HTTP Transfer Coding registry, as defined in | |||
| Section 7.3. They are used in the TE (Section 5.6.5 of [Semantics]) | Section 7.3. They are used in the TE (Section 9.1.4 of [Semantics]) | |||
| and Transfer-Encoding (Section 6.1) header fields. | and Transfer-Encoding (Section 6.1) header fields. | |||
| ------------ ------------------------------- ----------- | ------------ ------------------------------- ----------- | |||
| Name Description Reference | Name Description Reference | |||
| ------------ ------------------------------- ----------- | ------------ ------------------------------- ----------- | |||
| chunked Transfer in a series of Section | chunked Transfer in a series of Section | |||
| chunks 7.1 | chunks 7.1 | |||
| compress UNIX "compress" data format Section | compress UNIX "compress" data format Section | |||
| [Welch] 7.2 | [Welch] 7.2 | |||
| deflate "deflate" compressed data Section | deflate "deflate" compressed data Section | |||
| skipping to change at page 23, line 28 ¶ | skipping to change at page 23, line 28 ¶ | |||
| x-compress Deprecated (alias for Section | x-compress Deprecated (alias for Section | |||
| compress) 7.2 | compress) 7.2 | |||
| x-gzip Deprecated (alias for gzip) Section | x-gzip Deprecated (alias for gzip) Section | |||
| 7.2 | 7.2 | |||
| ------------ ------------------------------- ----------- | ------------ ------------------------------- ----------- | |||
| Table 3 | Table 3 | |||
| | *Note:* the coding name "trailers" is reserved because its use | | *Note:* the coding name "trailers" is reserved because its use | |||
| | would conflict with the keyword "trailers" in the TE header | | would conflict with the keyword "trailers" in the TE header | |||
| | field (Section 5.6.5 of [Semantics]). | | field (Section 9.1.4 of [Semantics]). | |||
| 7.1. Chunked Transfer Coding | 7.1. Chunked Transfer Coding | |||
| The chunked transfer coding wraps the payload body in order to | The chunked transfer coding wraps the payload body in order to | |||
| transfer it as a series of chunks, each with its own size indicator, | transfer it as a series of chunks, each with its own size indicator, | |||
| followed by an OPTIONAL trailer section containing trailer fields. | followed by an OPTIONAL trailer section containing trailer fields. | |||
| Chunked enables content streams of unknown size to be transferred as | Chunked enables content streams of unknown size to be transferred as | |||
| a sequence of length-delimited buffers, which enables the sender to | a sequence of length-delimited buffers, which enables the sender to | |||
| retain connection persistence and the recipient to know when it has | retain connection persistence and the recipient to know when it has | |||
| received the entire message. | received the entire message. | |||
| skipping to change at page 26, line 11 ¶ | skipping to change at page 26, line 11 ¶ | |||
| Content-Length := length | Content-Length := length | |||
| Remove "chunked" from Transfer-Encoding | Remove "chunked" from Transfer-Encoding | |||
| Remove Trailer from existing header fields | Remove Trailer from existing header fields | |||
| 7.2. Transfer Codings for Compression | 7.2. Transfer Codings for Compression | |||
| The following transfer coding names for compression are defined by | The following transfer coding names for compression are defined by | |||
| the same algorithm as their corresponding content coding: | the same algorithm as their corresponding content coding: | |||
| compress (and x-compress) | compress (and x-compress) | |||
| See Section 7.1.2.1 of [Semantics]. | See Section 7.5.1.1 of [Semantics]. | |||
| deflate | deflate | |||
| See Section 7.1.2.2 of [Semantics]. | See Section 7.5.1.2 of [Semantics]. | |||
| gzip (and x-gzip) | gzip (and x-gzip) | |||
| See Section 7.1.2.3 of [Semantics]. | See Section 7.5.1.3 of [Semantics]. | |||
| The compression codings do not define any parameters. Their presence | The compression codings do not define any parameters. Their presence | |||
| SHOULD be treated as an error. | SHOULD be treated as an error. | |||
| 7.3. Transfer Coding Registry | 7.3. Transfer Coding Registry | |||
| The "HTTP Transfer Coding Registry" defines the namespace for | The "HTTP Transfer Coding Registry" defines the namespace for | |||
| transfer coding names. It is maintained at | transfer coding names. It is maintained at | |||
| <https://www.iana.org/assignments/http-parameters>. | <https://www.iana.org/assignments/http-parameters>. | |||
| Registrations MUST include the following fields: | Registrations MUST include the following fields: | |||
| o Name | o Name | |||
| o Description | o Description | |||
| o Pointer to specification text | o Pointer to specification text | |||
| Names of transfer codings MUST NOT overlap with names of content | Names of transfer codings MUST NOT overlap with names of content | |||
| codings (Section 7.1.2 of [Semantics]) unless the encoding | codings (Section 7.5.1 of [Semantics]) unless the encoding | |||
| transformation is identical, as is the case for the compression | transformation is identical, as is the case for the compression | |||
| codings defined in Section 7.2. | codings defined in Section 7.2. | |||
| The TE header field (Section 5.6.5 of [Semantics]) uses a pseudo | The TE header field (Section 9.1.4 of [Semantics]) uses a pseudo | |||
| parameter named "q" as rank value when multiple transfer codings are | parameter named "q" as rank value when multiple transfer codings are | |||
| acceptable. Future registrations of transfer codings SHOULD NOT | acceptable. Future registrations of transfer codings SHOULD NOT | |||
| define parameters called "q" (case-insensitively) in order to avoid | define parameters called "q" (case-insensitively) in order to avoid | |||
| ambiguities. | ambiguities. | |||
| Values to be added to this namespace require IETF Review (see | Values to be added to this namespace require IETF Review (see | |||
| Section 4.8 of [RFC8126]), and MUST conform to the purpose of | Section 4.8 of [RFC8126]), and MUST conform to the purpose of | |||
| transfer coding defined in this specification. | transfer coding defined in this specification. | |||
| Use of program names for the identification of encoding formats is | Use of program names for the identification of encoding formats is | |||
| not desirable and is discouraged for future encodings. | not desirable and is discouraged for future encodings. | |||
| 7.4. Negotiating Transfer Codings | 7.4. Negotiating Transfer Codings | |||
| The TE field (Section 5.6.5 of [Semantics]) is used in HTTP/1.1 to | The TE field (Section 9.1.4 of [Semantics]) is used in HTTP/1.1 to | |||
| indicate what transfer-codings, besides chunked, the client is | indicate what transfer-codings, besides chunked, the client is | |||
| willing to accept in the response, and whether or not the client is | willing to accept in the response, and whether or not the client is | |||
| willing to accept trailer fields in a chunked transfer coding. | willing to accept trailer fields in a chunked transfer coding. | |||
| A client MUST NOT send the chunked transfer coding name in TE; | A client MUST NOT send the chunked transfer coding name in TE; | |||
| chunked is always acceptable for HTTP/1.1 recipients. | chunked is always acceptable for HTTP/1.1 recipients. | |||
| Three examples of TE use are below. | Three examples of TE use are below. | |||
| TE: deflate | TE: deflate | |||
| TE: | TE: | |||
| TE: trailers, deflate;q=0.5 | TE: trailers, deflate;q=0.5 | |||
| When multiple transfer codings are acceptable, the client MAY rank | When multiple transfer codings are acceptable, the client MAY rank | |||
| the codings by preference using a case-insensitive "q" parameter | the codings by preference using a case-insensitive "q" parameter | |||
| (similar to the qvalues used in content negotiation fields, | (similar to the qvalues used in content negotiation fields, | |||
| Section 7.4.4 of [Semantics]). The rank value is a real number in | Section 11.1.1.2 of [Semantics]). The rank value is a real number in | |||
| the range 0 through 1, where 0.001 is the least preferred and 1 is | the range 0 through 1, where 0.001 is the least preferred and 1 is | |||
| the most preferred; a value of 0 means "not acceptable". | the most preferred; a value of 0 means "not acceptable". | |||
| If the TE field value is empty or if no TE field is present, the only | If the TE field value is empty or if no TE field is present, the only | |||
| acceptable transfer coding is chunked. A message with no transfer | acceptable transfer coding is chunked. A message with no transfer | |||
| coding is always acceptable. | coding is always acceptable. | |||
| The keyword "trailers" indicates that the sender will not discard | The keyword "trailers" indicates that the sender will not discard | |||
| trailer fields, as described in Section 5.6 of [Semantics]. | trailer fields, as described in Section 5.6 of [Semantics]. | |||
| Since the TE header field only applies to the immediate connection, a | Since the TE header field only applies to the immediate connection, a | |||
| sender of TE MUST also send a "TE" connection option within the | sender of TE MUST also send a "TE" connection option within the | |||
| Connection header field (Section 6.8 of [Semantics]) in order to | Connection header field (Section 6.4.1 of [Semantics]) in order to | |||
| prevent the TE field from being forwarded by intermediaries that do | prevent the TE field from being forwarded by intermediaries that do | |||
| not support its semantics. | not support its semantics. | |||
| 8. Handling Incomplete Messages | 8. Handling Incomplete Messages | |||
| A server that receives an incomplete request message, usually due to | A server that receives an incomplete request message, usually due to | |||
| a canceled request or a triggered timeout exception, MAY send an | a canceled request or a triggered timeout exception, MAY send an | |||
| error response prior to closing the connection. | error response prior to closing the connection. | |||
| A client that receives an incomplete response message, which can | A client that receives an incomplete response message, which can | |||
| skipping to change at page 28, line 30 ¶ | skipping to change at page 28, line 30 ¶ | |||
| 9. Connection Management | 9. Connection Management | |||
| HTTP messaging is independent of the underlying transport- or | HTTP messaging is independent of the underlying transport- or | |||
| session-layer connection protocol(s). HTTP only presumes a reliable | session-layer connection protocol(s). HTTP only presumes a reliable | |||
| transport with in-order delivery of requests and the corresponding | transport with in-order delivery of requests and the corresponding | |||
| in-order delivery of responses. The mapping of HTTP request and | in-order delivery of responses. The mapping of HTTP request and | |||
| response structures onto the data units of an underlying transport | response structures onto the data units of an underlying transport | |||
| protocol is outside the scope of this specification. | protocol is outside the scope of this specification. | |||
| As described in Section 6.3 of [Semantics], the specific connection | As described in Section 6.2 of [Semantics], the specific connection | |||
| protocols to be used for an HTTP interaction are determined by client | protocols to be used for an HTTP interaction are determined by client | |||
| configuration and the target URI. For example, the "http" URI scheme | configuration and the target URI. For example, the "http" URI scheme | |||
| (Section 2.5.1 of [Semantics]) indicates a default connection of TCP | (Section 4.2.1 of [Semantics]) indicates a default connection of TCP | |||
| over IP, with a default TCP port of 80, but the client might be | over IP, with a default TCP port of 80, but the client might be | |||
| configured to use a proxy via some other connection, port, or | configured to use a proxy via some other connection, port, or | |||
| protocol. | protocol. | |||
| HTTP implementations are expected to engage in connection management, | HTTP implementations are expected to engage in connection management, | |||
| which includes maintaining the state of current connections, | which includes maintaining the state of current connections, | |||
| establishing a new connection or reusing an existing connection, | establishing a new connection or reusing an existing connection, | |||
| processing messages received on a connection, detecting connection | processing messages received on a connection, detecting connection | |||
| failures, and closing each connection. Most clients maintain | failures, and closing each connection. Most clients maintain | |||
| multiple connections in parallel, including more than one connection | multiple connections in parallel, including more than one connection | |||
| skipping to change at page 29, line 13 ¶ | skipping to change at page 29, line 13 ¶ | |||
| protocols. Each connection applies to only one transport link. | protocols. Each connection applies to only one transport link. | |||
| 9.2. Associating a Response to a Request | 9.2. Associating a Response to a Request | |||
| HTTP/1.1 does not include a request identifier for associating a | HTTP/1.1 does not include a request identifier for associating a | |||
| given request message with its corresponding one or more response | given request message with its corresponding one or more response | |||
| messages. Hence, it relies on the order of response arrival to | messages. Hence, it relies on the order of response arrival to | |||
| correspond exactly to the order in which requests are made on the | correspond exactly to the order in which requests are made on the | |||
| same connection. More than one response message per request only | same connection. More than one response message per request only | |||
| occurs when one or more informational responses (1xx, see | occurs when one or more informational responses (1xx, see | |||
| Section 10.2 of [Semantics]) precede a final response to the same | Section 14.2 of [Semantics]) precede a final response to the same | |||
| request. | request. | |||
| A client that has more than one outstanding request on a connection | A client that has more than one outstanding request on a connection | |||
| MUST maintain a list of outstanding requests in the order sent and | MUST maintain a list of outstanding requests in the order sent and | |||
| MUST associate each received response message on that connection to | MUST associate each received response message on that connection to | |||
| the highest ordered request that has not yet received a final (non- | the highest ordered request that has not yet received a final (non- | |||
| 1xx) response. | 1xx) response. | |||
| If an HTTP/1.1 client receives data on a connection that doesn't have | If an HTTP/1.1 client receives data on a connection that doesn't have | |||
| any outstanding requests, it MUST NOT consider them to be a response | any outstanding requests, it MUST NOT consider them to be a response | |||
| skipping to change at page 29, line 38 ¶ | skipping to change at page 29, line 38 ¶ | |||
| 9.3. Persistence | 9.3. Persistence | |||
| HTTP/1.1 defaults to the use of "persistent connections", allowing | HTTP/1.1 defaults to the use of "persistent connections", allowing | |||
| multiple requests and responses to be carried over a single | multiple requests and responses to be carried over a single | |||
| connection. The "close" connection option is used to signal that a | connection. The "close" connection option is used to signal that a | |||
| connection will not persist after the current request/response. HTTP | connection will not persist after the current request/response. HTTP | |||
| implementations SHOULD support persistent connections. | implementations SHOULD support persistent connections. | |||
| A recipient determines whether a connection is persistent or not | A recipient determines whether a connection is persistent or not | |||
| based on the most recently received message's protocol version and | based on the most recently received message's protocol version and | |||
| Connection header field (Section 6.8 of [Semantics]), if any: | Connection header field (Section 6.4.1 of [Semantics]), if any: | |||
| o If the "close" connection option is present, the connection will | o If the "close" connection option is present, the connection will | |||
| not persist after the current response; else, | not persist after the current response; else, | |||
| o If the received protocol is HTTP/1.1 (or later), the connection | o If the received protocol is HTTP/1.1 (or later), the connection | |||
| will persist after the current response; else, | will persist after the current response; else, | |||
| o If the received protocol is HTTP/1.0, the "keep-alive" connection | o If the received protocol is HTTP/1.0, the "keep-alive" connection | |||
| option is present, either the recipient is not a proxy or the | option is present, either the recipient is not a proxy or the | |||
| message is a response, and the recipient wishes to honor the | message is a response, and the recipient wishes to honor the | |||
| skipping to change at page 32, line 42 ¶ | skipping to change at page 32, line 42 ¶ | |||
| A client sending a message body SHOULD monitor the network connection | A client sending a message body SHOULD monitor the network connection | |||
| for an error response while it is transmitting the request. If the | for an error response while it is transmitting the request. If the | |||
| client sees a response that indicates the server does not wish to | client sees a response that indicates the server does not wish to | |||
| receive the message body and is closing the connection, the client | receive the message body and is closing the connection, the client | |||
| SHOULD immediately cease transmitting the body and close its side of | SHOULD immediately cease transmitting the body and close its side of | |||
| the connection. | the connection. | |||
| 9.6. Tear-down | 9.6. Tear-down | |||
| The Connection header field (Section 6.8 of [Semantics]) provides a | The Connection header field (Section 6.4.1 of [Semantics]) provides a | |||
| "close" connection option that a sender SHOULD send when it wishes to | "close" connection option that a sender SHOULD send when it wishes to | |||
| close the connection after the current request/response pair. | close the connection after the current request/response pair. | |||
| A client that sends a "close" connection option MUST NOT send further | A client that sends a "close" connection option MUST NOT send further | |||
| requests on that connection (after the one containing "close") and | requests on that connection (after the one containing "close") and | |||
| MUST close the connection after reading the final response message | MUST close the connection after reading the final response message | |||
| corresponding to this request. | corresponding to this request. | |||
| A server that receives a "close" connection option MUST initiate a | A server that receives a "close" connection option MUST initiate a | |||
| close of the connection (see below) after it sends the final response | close of the connection (see below) after it sends the final response | |||
| skipping to change at page 39, line 31 ¶ | skipping to change at page 39, line 31 ¶ | |||
| 11.4. Message Confidentiality | 11.4. Message Confidentiality | |||
| HTTP relies on underlying transport protocols to provide message | HTTP relies on underlying transport protocols to provide message | |||
| confidentiality when that is desired. HTTP has been specifically | confidentiality when that is desired. HTTP has been specifically | |||
| designed to be independent of the transport protocol, such that it | designed to be independent of the transport protocol, such that it | |||
| can be used over many different forms of encrypted connection, with | can be used over many different forms of encrypted connection, with | |||
| the selection of such transports being identified by the choice of | the selection of such transports being identified by the choice of | |||
| URI scheme or within user agent configuration. | URI scheme or within user agent configuration. | |||
| The "https" scheme can be used to identify resources that require a | The "https" scheme can be used to identify resources that require a | |||
| confidential connection, as described in Section 2.5.2 of | confidential connection, as described in Section 4.2.2 of | |||
| [Semantics]. | [Semantics]. | |||
| 12. IANA Considerations | 12. IANA Considerations | |||
| The change controller for the following registrations is: "IETF | The change controller for the following registrations is: "IETF | |||
| (iesg@ietf.org) - Internet Engineering Task Force". | (iesg@ietf.org) - Internet Engineering Task Force". | |||
| 12.1. Field Name Registration | 12.1. Field Name Registration | |||
| Please update the "Hypertext Transfer Protocol (HTTP) Field Name | Please update the "Hypertext Transfer Protocol (HTTP) Field Name | |||
| skipping to change at page 40, line 12 ¶ | skipping to change at page 40, line 12 ¶ | |||
| information in Section 10.1 and Section 10.2 for the media types | information in Section 10.1 and Section 10.2 for the media types | |||
| "message/http" and "application/http", respectively. | "message/http" and "application/http", respectively. | |||
| 12.3. Transfer Coding Registration | 12.3. Transfer Coding Registration | |||
| Please update the "HTTP Transfer Coding Registry" at | Please update the "HTTP Transfer Coding Registry" at | |||
| <https://www.iana.org/assignments/http-parameters/> with the | <https://www.iana.org/assignments/http-parameters/> with the | |||
| registration procedure of Section 7.3 and the content coding names | registration procedure of Section 7.3 and the content coding names | |||
| summarized in the table of Section 7. | summarized in the table of Section 7. | |||
| 12.4. Upgrade Token Registration | 12.4. ALPN Protocol ID Registration | |||
| Please update the "Hypertext Transfer Protocol (HTTP) Upgrade Token | ||||
| Registry" at <https://www.iana.org/assignments/http-upgrade-tokens> | ||||
| with the registration procedure of Section 6.7.2 of [Semantics] and | ||||
| the upgrade token names summarized in the table of Section 6.7.1 of | ||||
| [Semantics]. | ||||
| 12.5. ALPN Protocol ID Registration | ||||
| Please update the "TLS Application-Layer Protocol Negotiation (ALPN) | Please update the "TLS Application-Layer Protocol Negotiation (ALPN) | |||
| Protocol IDs" registry at <https://www.iana.org/assignments/tls- | Protocol IDs" registry at <https://www.iana.org/assignments/tls- | |||
| extensiontype-values/tls-extensiontype-values.xhtml> with the | extensiontype-values/tls-extensiontype-values.xhtml> with the | |||
| registration below: | registration below: | |||
| ---------- ----------------------------- ---------------- | ---------- ----------------------------- ---------------- | |||
| Protocol Identification Sequence Reference | Protocol Identification Sequence Reference | |||
| ---------- ----------------------------- ---------------- | ---------- ----------------------------- ---------------- | |||
| HTTP/1.1 0x68 0x74 0x74 0x70 0x2f (this | HTTP/1.1 0x68 0x74 0x74 0x70 0x2f (this | |||
| 0x31 0x2e 0x31 ("http/1.1") specification) | 0x31 0x2e 0x31 ("http/1.1") specification) | |||
| ---------- ----------------------------- ---------------- | ---------- ----------------------------- ---------------- | |||
| Table 4 | Table 4 | |||
| 13. References | 13. References | |||
| 13.1. Normative References | 13.1. Normative References | |||
| [Caching] Fielding, R., Ed., Nottingham, M., Ed., and J. F. Reschke, | [Caching] Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke, | |||
| Ed., "HTTP Caching", Work in Progress, Internet-Draft, | Ed., "HTTP Caching", Work in Progress, Internet-Draft, | |||
| draft-ietf-httpbis-cache-11, August 27, 2020, | draft-ietf-httpbis-cache-12, October 2, 2020, | |||
| <https://tools.ietf.org/html/draft-ietf-httpbis-cache-11>. | <https://tools.ietf.org/html/draft-ietf-httpbis-cache-12>. | |||
| [RFC1950] Deutsch, L.P. and J-L. Gailly, "ZLIB Compressed Data | [RFC1950] Deutsch, L.P. and J-L. Gailly, "ZLIB Compressed Data | |||
| Format Specification version 3.3", RFC 1950, | Format Specification version 3.3", RFC 1950, | |||
| DOI 10.17487/RFC1950, May 1996, | DOI 10.17487/RFC1950, May 1996, | |||
| <https://www.rfc-editor.org/info/rfc1950>. | <https://www.rfc-editor.org/info/rfc1950>. | |||
| [RFC1951] Deutsch, P., "DEFLATE Compressed Data Format Specification | [RFC1951] Deutsch, P., "DEFLATE Compressed Data Format Specification | |||
| version 1.3", RFC 1951, DOI 10.17487/RFC1951, May 1996, | version 1.3", RFC 1951, DOI 10.17487/RFC1951, May 1996, | |||
| <https://www.rfc-editor.org/info/rfc1951>. | <https://www.rfc-editor.org/info/rfc1951>. | |||
| skipping to change at page 41, line 38 ¶ | skipping to change at page 41, line 33 ¶ | |||
| [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC | [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC | |||
| 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, | 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, | |||
| May 2017, <https://www.rfc-editor.org/info/rfc8174>. | May 2017, <https://www.rfc-editor.org/info/rfc8174>. | |||
| [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol | [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol | |||
| Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, | Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, | |||
| <https://www.rfc-editor.org/info/rfc8446>. | <https://www.rfc-editor.org/info/rfc8446>. | |||
| [Semantics] | [Semantics] | |||
| Fielding, R., Ed., Nottingham, M., Ed., and J. F. Reschke, | Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke, | |||
| Ed., "HTTP Semantics", Work in Progress, Internet-Draft, | Ed., "HTTP Semantics", Work in Progress, Internet-Draft, | |||
| draft-ietf-httpbis-semantics-11, August 27, 2020, | draft-ietf-httpbis-semantics-12, October 2, 2020, | |||
| <https://tools.ietf.org/html/draft-ietf-httpbis-semantics- | <https://tools.ietf.org/html/draft-ietf-httpbis-semantics- | |||
| 11>. | 12>. | |||
| [USASCII] American National Standards Institute, "Coded Character | [USASCII] American National Standards Institute, "Coded Character | |||
| Set -- 7-bit American Standard Code for Information | Set -- 7-bit American Standard Code for Information | |||
| Interchange", ANSI X3.4, 1986. | Interchange", ANSI X3.4, 1986. | |||
| [Welch] Welch, T. A., "A Technique for High-Performance Data | [Welch] Welch, T. A., "A Technique for High-Performance Data | |||
| Compression", IEEE Computer 17(6), June 1984. | Compression", IEEE Computer 17(6), June 1984. | |||
| 13.2. Informative References | 13.2. Informative References | |||
| skipping to change at page 43, line 23 ¶ | skipping to change at page 43, line 18 ¶ | |||
| <https://www.rfc-editor.org/info/rfc7231>. | <https://www.rfc-editor.org/info/rfc7231>. | |||
| [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for | [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for | |||
| Writing an IANA Considerations Section in RFCs", BCP 26, | Writing an IANA Considerations Section in RFCs", BCP 26, | |||
| RFC 8126, DOI 10.17487/RFC8126, June 2017, | RFC 8126, DOI 10.17487/RFC8126, June 2017, | |||
| <https://www.rfc-editor.org/info/rfc8126>. | <https://www.rfc-editor.org/info/rfc8126>. | |||
| Appendix A. Collected ABNF | Appendix A. Collected ABNF | |||
| In the collected ABNF below, list rules are expanded as per | In the collected ABNF below, list rules are expanded as per | |||
| Section 5.5.1 of [Semantics]. | Section 5.7.1.1 of [Semantics]. | |||
| BWS = <BWS, see [Semantics], Section 1.6.1> | BWS = <BWS, see [Semantics], Section 5.7.3> | |||
| HTTP-message = start-line CRLF *( field-line CRLF ) CRLF [ | HTTP-message = start-line CRLF *( field-line CRLF ) CRLF [ | |||
| message-body ] | message-body ] | |||
| HTTP-name = %x48.54.54.50 ; HTTP | HTTP-name = %x48.54.54.50 ; HTTP | |||
| HTTP-version = HTTP-name "/" DIGIT "." DIGIT | HTTP-version = HTTP-name "/" DIGIT "." DIGIT | |||
| OWS = <OWS, see [Semantics], Section 1.6.1> | OWS = <OWS, see [Semantics], Section 5.7.3> | |||
| RWS = <RWS, see [Semantics], Section 1.6.1> | RWS = <RWS, see [Semantics], Section 5.7.3> | |||
| Transfer-Encoding = [ transfer-coding *( OWS "," OWS transfer-coding | Transfer-Encoding = [ transfer-coding *( OWS "," OWS transfer-coding | |||
| ) ] | ) ] | |||
| absolute-URI = <absolute-URI, see [RFC3986], Section 4.3> | absolute-URI = <absolute-URI, see [RFC3986], Section 4.3> | |||
| absolute-form = absolute-URI | absolute-form = absolute-URI | |||
| absolute-path = <absolute-path, see [Semantics], Section 2.4> | absolute-path = <absolute-path, see [Semantics], Section 4> | |||
| asterisk-form = "*" | asterisk-form = "*" | |||
| authority = <authority, see [RFC3986], Section 3.2> | authority = <authority, see [RFC3986], Section 3.2> | |||
| authority-form = authority | authority-form = authority | |||
| chunk = chunk-size [ chunk-ext ] CRLF chunk-data CRLF | chunk = chunk-size [ chunk-ext ] CRLF chunk-data CRLF | |||
| chunk-data = 1*OCTET | chunk-data = 1*OCTET | |||
| chunk-ext = *( BWS ";" BWS chunk-ext-name [ BWS "=" BWS chunk-ext-val | chunk-ext = *( BWS ";" BWS chunk-ext-name [ BWS "=" BWS chunk-ext-val | |||
| ] ) | ] ) | |||
| chunk-ext-name = token | chunk-ext-name = token | |||
| chunk-ext-val = token / quoted-string | chunk-ext-val = token / quoted-string | |||
| chunk-size = 1*HEXDIG | chunk-size = 1*HEXDIG | |||
| chunked-body = *chunk last-chunk trailer-section CRLF | chunked-body = *chunk last-chunk trailer-section CRLF | |||
| comment = <comment, see [Semantics], Section 5.4.1.3> | comment = <comment, see [Semantics], Section 5.7.5> | |||
| field-line = field-name ":" OWS field-value OWS | field-line = field-name ":" OWS field-value OWS | |||
| field-name = <field-name, see [Semantics], Section 5.3> | field-name = <field-name, see [Semantics], Section 5.4.3> | |||
| field-value = <field-value, see [Semantics], Section 5.4> | field-value = <field-value, see [Semantics], Section 5.4.4> | |||
| last-chunk = 1*"0" [ chunk-ext ] CRLF | last-chunk = 1*"0" [ chunk-ext ] CRLF | |||
| message-body = *OCTET | message-body = *OCTET | |||
| method = token | method = token | |||
| obs-fold = OWS CRLF RWS | obs-fold = OWS CRLF RWS | |||
| obs-text = <obs-text, see [Semantics], Section 5.4.1.2> | obs-text = <obs-text, see [Semantics], Section 5.7.4> | |||
| origin-form = absolute-path [ "?" query ] | origin-form = absolute-path [ "?" query ] | |||
| port = <port, see [RFC3986], Section 3.2.3> | port = <port, see [RFC3986], Section 3.2.3> | |||
| query = <query, see [RFC3986], Section 3.4> | query = <query, see [RFC3986], Section 3.4> | |||
| quoted-string = <quoted-string, see [Semantics], Section 5.4.1.2> | quoted-string = <quoted-string, see [Semantics], Section 5.7.4> | |||
| reason-phrase = 1*( HTAB / SP / VCHAR / obs-text ) | reason-phrase = 1*( HTAB / SP / VCHAR / obs-text ) | |||
| request-line = method SP request-target SP HTTP-version | request-line = method SP request-target SP HTTP-version | |||
| request-target = origin-form / absolute-form / authority-form / | request-target = origin-form / absolute-form / authority-form / | |||
| asterisk-form | asterisk-form | |||
| start-line = request-line / status-line | start-line = request-line / status-line | |||
| status-code = 3DIGIT | status-code = 3DIGIT | |||
| status-line = HTTP-version SP status-code SP [ reason-phrase ] | status-line = HTTP-version SP status-code SP [ reason-phrase ] | |||
| token = <token, see [Semantics], Section 5.4.1.1> | token = <token, see [Semantics], Section 5.7.2> | |||
| trailer-section = *( field-line CRLF ) | trailer-section = *( field-line CRLF ) | |||
| transfer-coding = token *( OWS ";" OWS transfer-parameter ) | transfer-coding = token *( OWS ";" OWS transfer-parameter ) | |||
| transfer-parameter = token BWS "=" BWS ( token / quoted-string ) | transfer-parameter = token BWS "=" BWS ( token / quoted-string ) | |||
| uri-host = <host, see [RFC3986], Section 3.2.2> | uri-host = <host, see [RFC3986], Section 3.2.2> | |||
| Appendix B. Differences between HTTP and MIME | Appendix B. Differences between HTTP and MIME | |||
| HTTP/1.1 uses many of the constructs defined for the Internet Message | HTTP/1.1 uses many of the constructs defined for the Internet Message | |||
| Format [RFC5322] and the Multipurpose Internet Mail Extensions (MIME) | Format [RFC5322] and the Multipurpose Internet Mail Extensions (MIME) | |||
| skipping to change at page 45, line 26 ¶ | skipping to change at page 45, line 24 ¶ | |||
| MIME protocol was used to construct the message. Use of the MIME- | MIME protocol was used to construct the message. Use of the MIME- | |||
| Version header field indicates that the message is in full | Version header field indicates that the message is in full | |||
| conformance with the MIME protocol (as defined in [RFC2045]). | conformance with the MIME protocol (as defined in [RFC2045]). | |||
| Senders are responsible for ensuring full conformance (where | Senders are responsible for ensuring full conformance (where | |||
| possible) when exporting HTTP messages to strict MIME environments. | possible) when exporting HTTP messages to strict MIME environments. | |||
| B.2. Conversion to Canonical Form | B.2. Conversion to Canonical Form | |||
| MIME requires that an Internet mail body part be converted to | MIME requires that an Internet mail body part be converted to | |||
| canonical form prior to being transferred, as described in Section 4 | canonical form prior to being transferred, as described in Section 4 | |||
| of [RFC2049]. Section 7.1.1.2 of [Semantics] describes the forms | of [RFC2049]. Section 7.4.3 of [Semantics] describes the forms | |||
| allowed for subtypes of the "text" media type when transmitted over | allowed for subtypes of the "text" media type when transmitted over | |||
| HTTP. [RFC2046] requires that content with a type of "text" | HTTP. [RFC2046] requires that content with a type of "text" | |||
| represent line breaks as CRLF and forbids the use of CR or LF outside | represent line breaks as CRLF and forbids the use of CR or LF outside | |||
| of line break sequences. HTTP allows CRLF, bare CR, and bare LF to | of line break sequences. HTTP allows CRLF, bare CR, and bare LF to | |||
| indicate a line break within text content. | indicate a line break within text content. | |||
| A proxy or gateway from HTTP to a strict MIME environment ought to | A proxy or gateway from HTTP to a strict MIME environment ought to | |||
| translate all line breaks within text media types to the RFC 2049 | translate all line breaks within text media types to the RFC 2049 | |||
| canonical form of CRLF. Note, however, this might be complicated by | canonical form of CRLF. Note, however, this might be complicated by | |||
| the presence of a Content-Encoding and by the fact that HTTP allows | the presence of a Content-Encoding and by the fact that HTTP allows | |||
| the use of some charsets that do not use octets 13 and 10 to | the use of some charsets that do not use octets 13 and 10 to | |||
| represent CR and LF, respectively. | represent CR and LF, respectively. | |||
| Conversion will break any cryptographic checksums applied to the | Conversion will break any cryptographic checksums applied to the | |||
| original content unless the original content is already in canonical | original content unless the original content is already in canonical | |||
| form. Therefore, the canonical form is recommended for any content | form. Therefore, the canonical form is recommended for any content | |||
| that uses such checksums in HTTP. | that uses such checksums in HTTP. | |||
| B.3. Conversion of Date Formats | B.3. Conversion of Date Formats | |||
| HTTP/1.1 uses a restricted set of date formats (Section 5.4.1.5 of | HTTP/1.1 uses a restricted set of date formats (Section 5.7.7 of | |||
| [Semantics]) to simplify the process of date comparison. Proxies and | [Semantics]) to simplify the process of date comparison. Proxies and | |||
| gateways from other protocols ought to ensure that any Date header | gateways from other protocols ought to ensure that any Date header | |||
| field present in a message conforms to one of the HTTP/1.1 formats | field present in a message conforms to one of the HTTP/1.1 formats | |||
| and rewrite the date if necessary. | and rewrite the date if necessary. | |||
| B.4. Conversion of Content-Encoding | B.4. Conversion of Content-Encoding | |||
| MIME does not include any concept equivalent to HTTP/1.1's Content- | MIME does not include any concept equivalent to HTTP/1.1's Content- | |||
| Encoding header field. Since this acts as a modifier on the media | Encoding header field. Since this acts as a modifier on the media | |||
| type, proxies and gateways from HTTP to MIME-compliant protocols | type, proxies and gateways from HTTP to MIME-compliant protocols | |||
| skipping to change at page 46, line 40 ¶ | skipping to change at page 46, line 40 ¶ | |||
| likelihood of safe transport over the destination protocol. | likelihood of safe transport over the destination protocol. | |||
| B.6. MHTML and Line Length Limitations | B.6. MHTML and Line Length Limitations | |||
| HTTP implementations that share code with MHTML [RFC2557] | HTTP implementations that share code with MHTML [RFC2557] | |||
| implementations need to be aware of MIME line length limitations. | implementations need to be aware of MIME line length limitations. | |||
| Since HTTP does not have this limitation, HTTP does not fold long | Since HTTP does not have this limitation, HTTP does not fold long | |||
| lines. MHTML messages being transported by HTTP follow all | lines. MHTML messages being transported by HTTP follow all | |||
| conventions of MHTML, including line length limitations and folding, | conventions of MHTML, including line length limitations and folding, | |||
| canonicalization, etc., since HTTP transfers message-bodies as | canonicalization, etc., since HTTP transfers message-bodies as | |||
| payload and, aside from the "multipart/byteranges" type | payload and, aside from the "multipart/byteranges" type (Section 13.5 | |||
| (Section 7.3.5 of [Semantics]), does not interpret the content or any | of [Semantics]), does not interpret the content or any MIME header | |||
| MIME header lines that might be contained therein. | lines that might be contained therein. | |||
| Appendix C. HTTP Version History | Appendix C. HTTP Version History | |||
| HTTP has been in use since 1990. The first version, later referred | HTTP has been in use since 1990. The first version, later referred | |||
| to as HTTP/0.9, was a simple protocol for hypertext data transfer | to as HTTP/0.9, was a simple protocol for hypertext data transfer | |||
| across the Internet, using only a single request method (GET) and no | across the Internet, using only a single request method (GET) and no | |||
| metadata. HTTP/1.0, as defined by [RFC1945], added a range of | metadata. HTTP/1.0, as defined by [RFC1945], added a range of | |||
| request methods and MIME-like messaging, allowing for metadata to be | request methods and MIME-like messaging, allowing for metadata to be | |||
| transferred and modifiers placed on the request/response semantics. | transferred and modifiers placed on the request/response semantics. | |||
| However, HTTP/1.0 did not sufficiently take into consideration the | However, HTTP/1.0 did not sufficiently take into consideration the | |||
| skipping to change at page 47, line 40 ¶ | skipping to change at page 47, line 40 ¶ | |||
| properly encode the request-target. | properly encode the request-target. | |||
| C.1. Changes from HTTP/1.0 | C.1. Changes from HTTP/1.0 | |||
| This section summarizes major differences between versions HTTP/1.0 | This section summarizes major differences between versions HTTP/1.0 | |||
| and HTTP/1.1. | and HTTP/1.1. | |||
| C.1.1. Multihomed Web Servers | C.1.1. Multihomed Web Servers | |||
| The requirements that clients and servers support the Host header | The requirements that clients and servers support the Host header | |||
| field (Section 6.5 of [Semantics]), report an error if it is missing | field (Section 6.1.2 of [Semantics]), report an error if it is | |||
| from an HTTP/1.1 request, and accept absolute URIs (Section 3.2) are | missing from an HTTP/1.1 request, and accept absolute URIs | |||
| among the most important changes defined by HTTP/1.1. | (Section 3.2) are among the most important changes defined by | |||
| HTTP/1.1. | ||||
| Older HTTP/1.0 clients assumed a one-to-one relationship of IP | Older HTTP/1.0 clients assumed a one-to-one relationship of IP | |||
| addresses and servers; there was no other established mechanism for | addresses and servers; there was no other established mechanism for | |||
| distinguishing the intended server of a request than the IP address | distinguishing the intended server of a request than the IP address | |||
| to which that request was directed. The Host header field was | to which that request was directed. The Host header field was | |||
| introduced during the development of HTTP/1.1 and, though it was | introduced during the development of HTTP/1.1 and, though it was | |||
| quickly implemented by most HTTP/1.0 browsers, additional | quickly implemented by most HTTP/1.0 browsers, additional | |||
| requirements were placed on all HTTP/1.1 requests in order to ensure | requirements were placed on all HTTP/1.1 requests in order to ensure | |||
| complete adoption. At the time of this writing, most HTTP-based | complete adoption. At the time of this writing, most HTTP-based | |||
| services are dependent upon the Host header field for targeting | services are dependent upon the Host header field for targeting | |||
| skipping to change at page 51, line 40 ¶ | skipping to change at page 51, line 40 ¶ | |||
| o In Section 7, remove the predefined codings from the ABNF and make | o In Section 7, remove the predefined codings from the ABNF and make | |||
| it generic instead (<https://github.com/httpwg/http-core/ | it generic instead (<https://github.com/httpwg/http-core/ | |||
| issues/66>) | issues/66>) | |||
| o Use RFC 7405 ABNF notation for case-sensitive string constants | o Use RFC 7405 ABNF notation for case-sensitive string constants | |||
| (<https://github.com/httpwg/http-core/issues/133>) | (<https://github.com/httpwg/http-core/issues/133>) | |||
| D.6. Since draft-ietf-httpbis-messaging-04 | D.6. Since draft-ietf-httpbis-messaging-04 | |||
| o In Section 6.7 of [Semantics], clarify that protocol-name is to be | o In Section 6.6 of [Semantics], clarify that protocol-name is to be | |||
| matched case-insensitively (<https://github.com/httpwg/http-core/ | matched case-insensitively (<https://github.com/httpwg/http-core/ | |||
| issues/8>) | issues/8>) | |||
| o In Section 5.2, add leading optional whitespace to obs-fold ABNF | o In Section 5.2, add leading optional whitespace to obs-fold ABNF | |||
| (<https://github.com/httpwg/http-core/issues/19>, | (<https://github.com/httpwg/http-core/issues/19>, | |||
| <https://www.rfc-editor.org/errata/eid4189>) | <https://www.rfc-editor.org/errata/eid4189>) | |||
| o In Section 4, add clarifications about empty reason phrases | o In Section 4, add clarifications about empty reason phrases | |||
| (<https://github.com/httpwg/http-core/issues/197>) | (<https://github.com/httpwg/http-core/issues/197>) | |||
| skipping to change at page 52, line 21 ¶ | skipping to change at page 52, line 21 ¶ | |||
| fields only if understood and defined as being mergeable | fields only if understood and defined as being mergeable | |||
| (<https://github.com/httpwg/http-core/issues/16>) | (<https://github.com/httpwg/http-core/issues/16>) | |||
| o In Section 2.1 and related Sections, move the trailing CRLF from | o In Section 2.1 and related Sections, move the trailing CRLF from | |||
| the line grammars into the message format | the line grammars into the message format | |||
| (<https://github.com/httpwg/http-core/issues/62>) | (<https://github.com/httpwg/http-core/issues/62>) | |||
| o Moved Section 2.3 down (<https://github.com/httpwg/http-core/ | o Moved Section 2.3 down (<https://github.com/httpwg/http-core/ | |||
| issues/68>) | issues/68>) | |||
| o In Section 6.7 of [Semantics], use 'websocket' instead of | o In Section 6.6 of [Semantics], use 'websocket' instead of | |||
| 'HTTP/2.0' in examples (<https://github.com/httpwg/http-core/ | 'HTTP/2.0' in examples (<https://github.com/httpwg/http-core/ | |||
| issues/112>) | issues/112>) | |||
| o Move version non-specific text from Section 6 into semantics as | o Move version non-specific text from Section 6 into semantics as | |||
| "payload body" (<https://github.com/httpwg/http-core/issues/159>) | "payload body" (<https://github.com/httpwg/http-core/issues/159>) | |||
| o In Section 9.8, add text from RFC 2818 | o In Section 9.8, add text from RFC 2818 | |||
| (<https://github.com/httpwg/http-core/issues/236>) | (<https://github.com/httpwg/http-core/issues/236>) | |||
| D.8. Since draft-ietf-httpbis-messaging-06 | D.8. Since draft-ietf-httpbis-messaging-06 | |||
| o In Section 12.5, update the APLN protocol id for HTTP/1.1 | o In Section 12.4, update the APLN protocol id for HTTP/1.1 | |||
| (<https://github.com/httpwg/http-core/issues/49>) | (<https://github.com/httpwg/http-core/issues/49>) | |||
| o In Section 5, align with updates to field terminology in semantics | o In Section 5, align with updates to field terminology in semantics | |||
| (<https://github.com/httpwg/http-core/issues/111>) | (<https://github.com/httpwg/http-core/issues/111>) | |||
| o In Section 6.8 of [Semantics], clarify that new connection options | o In Section 6.4.1 of [Semantics], clarify that new connection | |||
| indeed need to be registered (<https://github.com/httpwg/http- | options indeed need to be registered (<https://github.com/httpwg/ | |||
| core/issues/285>) | http-core/issues/285>) | |||
| o In Section 1.1, reference RFC 8174 as well | o In Section 1.1, reference RFC 8174 as well | |||
| (<https://github.com/httpwg/http-core/issues/303>) | (<https://github.com/httpwg/http-core/issues/303>) | |||
| D.9. Since draft-ietf-httpbis-messaging-07 | D.9. Since draft-ietf-httpbis-messaging-07 | |||
| o Move TE: trailers into [Semantics] (<https://github.com/httpwg/ | o Move TE: trailers into [Semantics] (<https://github.com/httpwg/ | |||
| http-core/issues/18>) | http-core/issues/18>) | |||
| o In Section 6.3, adjust requirements for handling multiple content- | o In Section 6.3, adjust requirements for handling multiple content- | |||
| skipping to change at page 53, line 48 ¶ | skipping to change at page 53, line 48 ¶ | |||
| o In Section 9.7, add text from RFC 2818 | o In Section 9.7, add text from RFC 2818 | |||
| (<https://github.com/httpwg/http-core/issues/236>) | (<https://github.com/httpwg/http-core/issues/236>) | |||
| o Moved definitions of "TE" and "Upgrade" into [Semantics] | o Moved definitions of "TE" and "Upgrade" into [Semantics] | |||
| (<https://github.com/httpwg/http-core/issues/392>) | (<https://github.com/httpwg/http-core/issues/392>) | |||
| o Moved definition of "Connection" into [Semantics] | o Moved definition of "Connection" into [Semantics] | |||
| (<https://github.com/httpwg/http-core/issues/407>) | (<https://github.com/httpwg/http-core/issues/407>) | |||
| D.13. Since draft-ietf-httpbis-messaging-11 | ||||
| o Move IANA Upgrade Token Registry instructions to [Semantics] | ||||
| (<https://github.com/httpwg/http-core/issues/450>) | ||||
| Acknowledgments | Acknowledgments | |||
| See Appendix "Acknowledgments" of [Semantics]. | See Appendix "Acknowledgments" of [Semantics]. | |||
| Authors' Addresses | Authors' Addresses | |||
| Roy T. Fielding (editor) | Roy T. Fielding (editor) | |||
| Adobe | Adobe | |||
| 345 Park Ave | 345 Park Ave | |||
| San Jose, CA 95110 | San Jose, CA 95110 | |||
| skipping to change at page 54, line 24 ¶ | skipping to change at page 54, line 28 ¶ | |||
| URI: https://roy.gbiv.com/ | URI: https://roy.gbiv.com/ | |||
| Mark Nottingham (editor) | Mark Nottingham (editor) | |||
| Fastly | Fastly | |||
| Prahran VIC | Prahran VIC | |||
| Australia | Australia | |||
| Email: mnot@mnot.net | Email: mnot@mnot.net | |||
| URI: https://www.mnot.net/ | URI: https://www.mnot.net/ | |||
| Julian F. Reschke (editor) | Julian Reschke (editor) | |||
| greenbytes GmbH | greenbytes GmbH | |||
| Hafenweg 16 | Hafenweg 16 | |||
| 48155 Münster | 48155 Münster | |||
| Germany | Germany | |||
| Email: julian.reschke@greenbytes.de | Email: julian.reschke@greenbytes.de | |||
| URI: https://greenbytes.de/tech/webdav/ | URI: https://greenbytes.de/tech/webdav/ | |||
| End of changes. 70 change blocks. | ||||
| 98 lines changed or deleted | 96 lines changed or added | |||
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