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diff --git a/vendor/sabre/dav/docs/rfc5785.txt b/vendor/sabre/dav/docs/rfc5785.txt deleted file mode 100644 index c28ccf6bf..000000000 --- a/vendor/sabre/dav/docs/rfc5785.txt +++ /dev/null @@ -1,451 +0,0 @@ - - - - - - -Internet Engineering Task Force (IETF) M. Nottingham -Request for Comments: 5785 E. Hammer-Lahav -Updates: 2616, 2818 April 2010 -Category: Standards Track -ISSN: 2070-1721 - - - Defining Well-Known Uniform Resource Identifiers (URIs) - -Abstract - - This memo defines a path prefix for "well-known locations", - "/.well-known/", in selected Uniform Resource Identifier (URI) - schemes. - -Status of This Memo - - This is an Internet Standards Track document. - - This document is a product of the Internet Engineering Task Force - (IETF). It represents the consensus of the IETF community. It has - received public review and has been approved for publication by the - Internet Engineering Steering Group (IESG). Further information on - Internet Standards is available in Section 2 of RFC 5741. - - Information about the current status of this document, any errata, - and how to provide feedback on it may be obtained at - http://www.rfc-editor.org/info/rfc5785. - -Copyright Notice - - Copyright (c) 2010 IETF Trust and the persons identified as the - document authors. All rights reserved. - - This document is subject to BCP 78 and the IETF Trust's Legal - Provisions Relating to IETF Documents - (http://trustee.ietf.org/license-info) in effect on the date of - publication of this document. Please review these documents - carefully, as they describe your rights and restrictions with respect - to this document. Code Components extracted from this document must - include Simplified BSD License text as described in Section 4.e of - the Trust Legal Provisions and are provided without warranty as - described in the Simplified BSD License. - - - - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 1] - -RFC 5785 Defining Well-Known URIs April 2010 - - -Table of Contents - - 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1.1. Appropriate Use of Well-Known URIs . . . . . . . . . . . . 3 - 2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 3 - 3. Well-Known URIs . . . . . . . . . . . . . . . . . . . . . . . . 3 - 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 - 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 - 5.1. The Well-Known URI Registry . . . . . . . . . . . . . . . . 4 - 5.1.1. Registration Template . . . . . . . . . . . . . . . . . 5 - 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 5 - 6.1. Normative References . . . . . . . . . . . . . . . . . . . 5 - 6.2. Informative References . . . . . . . . . . . . . . . . . . 5 - Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . . 7 - Appendix B. Frequently Asked Questions . . . . . . . . . . . . . . 7 - -1. Introduction - - It is increasingly common for Web-based protocols to require the - discovery of policy or other information about a host ("site-wide - metadata") before making a request. For example, the Robots - Exclusion Protocol <http://www.robotstxt.org/> specifies a way for - automated processes to obtain permission to access resources; - likewise, the Platform for Privacy Preferences [W3C.REC-P3P-20020416] - tells user-agents how to discover privacy policy beforehand. - - While there are several ways to access per-resource metadata (e.g., - HTTP headers, WebDAV's PROPFIND [RFC4918]), the perceived overhead - (either in terms of client-perceived latency and/or deployment - difficulties) associated with them often precludes their use in these - scenarios. - - When this happens, it is common to designate a "well-known location" - for such data, so that it can be easily located. However, this - approach has the drawback of risking collisions, both with other such - designated "well-known locations" and with pre-existing resources. - - To address this, this memo defines a path prefix in HTTP(S) URIs for - these "well-known locations", "/.well-known/". Future specifications - that need to define a resource for such site-wide metadata can - register their use to avoid collisions and minimise impingement upon - sites' URI space. - - - - - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 2] - -RFC 5785 Defining Well-Known URIs April 2010 - - -1.1. Appropriate Use of Well-Known URIs - - There are a number of possible ways that applications could use Well- - known URIs. However, in keeping with the Architecture of the World- - Wide Web [W3C.REC-webarch-20041215], well-known URIs are not intended - for general information retrieval or establishment of large URI - namespaces on the Web. Rather, they are designed to facilitate - discovery of information on a site when it isn't practical to use - other mechanisms; for example, when discovering policy that needs to - be evaluated before a resource is accessed, or when using multiple - round-trips is judged detrimental to performance. - - As such, the well-known URI space was created with the expectation - that it will be used to make site-wide policy information and other - metadata available directly (if sufficiently concise), or provide - references to other URIs that provide such metadata. - -2. Notational Conventions - - The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", - "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this - document are to be interpreted as described in RFC 2119 [RFC2119]. - -3. Well-Known URIs - - A well-known URI is a URI [RFC3986] whose path component begins with - the characters "/.well-known/", and whose scheme is "HTTP", "HTTPS", - or another scheme that has explicitly been specified to use well- - known URIs. - - Applications that wish to mint new well-known URIs MUST register - them, following the procedures in Section 5.1. - - For example, if an application registers the name 'example', the - corresponding well-known URI on 'http://www.example.com/' would be - 'http://www.example.com/.well-known/example'. - - Registered names MUST conform to the segment-nz production in - [RFC3986]. - - Note that this specification defines neither how to determine the - authority to use for a particular context, nor the scope of the - metadata discovered by dereferencing the well-known URI; both should - be defined by the application itself. - - Typically, a registration will reference a specification that defines - the format and associated media type to be obtained by dereferencing - the well-known URI. - - - -Nottingham & Hammer-Lahav Standards Track [Page 3] - -RFC 5785 Defining Well-Known URIs April 2010 - - - It MAY also contain additional information, such as the syntax of - additional path components, query strings and/or fragment identifiers - to be appended to the well-known URI, or protocol-specific details - (e.g., HTTP [RFC2616] method handling). - - Note that this specification does not define a format or media-type - for the resource located at "/.well-known/" and clients should not - expect a resource to exist at that location. - -4. Security Considerations - - This memo does not specify the scope of applicability of metadata or - policy obtained from a well-known URI, and does not specify how to - discover a well-known URI for a particular application. Individual - applications using this mechanism must define both aspects. - - Applications minting new well-known URIs, as well as administrators - deploying them, will need to consider several security-related - issues, including (but not limited to) exposure of sensitive data, - denial-of-service attacks (in addition to normal load issues), server - and client authentication, vulnerability to DNS rebinding attacks, - and attacks where limited access to a server grants the ability to - affect how well-known URIs are served. - -5. IANA Considerations - -5.1. The Well-Known URI Registry - - This document establishes the well-known URI registry. - - Well-known URIs are registered on the advice of one or more - Designated Experts (appointed by the IESG or their delegate), with a - Specification Required (using terminology from [RFC5226]). However, - to allow for the allocation of values prior to publication, the - Designated Expert(s) may approve registration once they are satisfied - that such a specification will be published. - - Registration requests should be sent to the - wellknown-uri-review@ietf.org mailing list for review and comment, - with an appropriate subject (e.g., "Request for well-known URI: - example"). - - Before a period of 14 days has passed, the Designated Expert(s) will - either approve or deny the registration request, communicating this - decision both to the review list and to IANA. Denials should include - an explanation and, if applicable, suggestions as to how to make the - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 4] - -RFC 5785 Defining Well-Known URIs April 2010 - - - request successful. Registration requests that are undetermined for - a period longer than 21 days can be brought to the IESG's attention - (using the iesg@iesg.org mailing list) for resolution. - -5.1.1. Registration Template - - URI suffix: The name requested for the well-known URI, relative to - "/.well-known/"; e.g., "example". - - Change controller: For Standards-Track RFCs, state "IETF". For - others, give the name of the responsible party. Other details - (e.g., postal address, e-mail address, home page URI) may also be - included. - - Specification document(s): Reference to the document that specifies - the field, preferably including a URI that can be used to retrieve - a copy of the document. An indication of the relevant sections - may also be included, but is not required. - - Related information: Optionally, citations to additional documents - containing further relevant information. - -6. References - -6.1. Normative References - - [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate - Requirement Levels", BCP 14, RFC 2119, March 1997. - - [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform - Resource Identifier (URI): Generic Syntax", STD 66, - RFC 3986, January 2005. - - [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an - IANA Considerations Section in RFCs", BCP 26, RFC 5226, - May 2008. - -6.2. Informative References - - [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, - L., Leach, P., and T. Berners-Lee, "Hypertext Transfer - Protocol -- HTTP/1.1", RFC 2616, June 1999. - - [RFC4918] Dusseault, L., "HTTP Extensions for Web Distributed - Authoring and Versioning (WebDAV)", RFC 4918, June 2007. - - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 5] - -RFC 5785 Defining Well-Known URIs April 2010 - - - [W3C.REC-P3P-20020416] - Marchiori, M., "The Platform for Privacy Preferences 1.0 - (P3P1.0) Specification", World Wide Web Consortium - Recommendation REC-P3P-20020416, April 2002, - <http://www.w3.org/TR/2002/ REC-P3P-20020416>. - - [W3C.REC-webarch-20041215] - Jacobs, I. and N. Walsh, "Architecture of the World Wide - Web, Volume One", World Wide Web Consortium - Recommendation REC- webarch-20041215, December 2004, - <http:// www.w3.org/TR/2004/REC-webarch-20041215>. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 6] - -RFC 5785 Defining Well-Known URIs April 2010 - - -Appendix A. Acknowledgements - - We would like to acknowledge the contributions of everyone who - provided feedback and use cases for this document; in particular, - Phil Archer, Dirk Balfanz, Adam Barth, Tim Bray, Brian Eaton, Brad - Fitzpatrick, Joe Gregorio, Paul Hoffman, Barry Leiba, Ashok Malhotra, - Breno de Medeiros, John Panzer, and Drummond Reed. However, they are - not responsible for errors and omissions. - -Appendix B. Frequently Asked Questions - - 1. Aren't well-known locations bad for the Web? - - They are, but for various reasons -- both technical and social -- - they are commonly used and their use is increasing. This memo - defines a "sandbox" for them, to reduce the risks of collision and - to minimise the impact upon pre-existing URIs on sites. - - 2. Why /.well-known? - - It's short, descriptive, and according to search indices, not - widely used. - - 3. What impact does this have on existing mechanisms, such as P3P and - robots.txt? - - None, until they choose to use this mechanism. - - 4. Why aren't per-directory well-known locations defined? - - Allowing every URI path segment to have a well-known location - (e.g., "/images/.well-known/") would increase the risks of - colliding with a pre-existing URI on a site, and generally these - solutions are found not to scale well, because they're too - "chatty". - - - - - - - - - - - - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 7] - -RFC 5785 Defining Well-Known URIs April 2010 - - -Authors' Addresses - - Mark Nottingham - - EMail: mnot@mnot.net - URI: http://www.mnot.net/ - - - Eran Hammer-Lahav - - EMail: eran@hueniverse.com - URI: http://hueniverse.com/ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -Nottingham & Hammer-Lahav Standards Track [Page 8] - |