Sieve Working Group P. Saint-Andre Internet-Draft Jabber Software Foundation Expires: January 22, 2007 A. Melnikov Isode Limited July 21, 2006 Sieve Notification Mechanism: xmpp draft-ietf-sieve-notify-xmpp-02 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on January 22, 2007. Copyright Notice Copyright (C) The Internet Society (2006). Abstract This document describes a profile of the Sieve extension for notifications, to allow notifications to be sent over the Extensible Messaging and Presence Protocol (XMPP), also known as Jabber. Saint-Andre & Melnikov Expires January 22, 2007 [Page 1] Internet-Draft SIEVE-XMPP July 2006 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Definition . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Notify tag ":method" . . . . . . . . . . . . . . . . . . . 3 2.2. Notify tag ":from" . . . . . . . . . . . . . . . . . . . . 4 2.3. Notify tag ":options" . . . . . . . . . . . . . . . . . . . 4 2.4. Notify tag ":priority" . . . . . . . . . . . . . . . . . . 4 2.5. Notify tag ":message" . . . . . . . . . . . . . . . . . . . 4 3. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4. Internationalization Considerations . . . . . . . . . . . . . . 5 5. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6 6.1. Normative References . . . . . . . . . . . . . . . . . . . 6 6.2. Informative References . . . . . . . . . . . . . . . . . . 6 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8 Intellectual Property and Copyright Statements . . . . . . . . . . 9 Saint-Andre & Melnikov Expires January 22, 2007 [Page 2] Internet-Draft SIEVE-XMPP July 2006 1. Introduction 1.1. Overview The [NOTIFY] extension to the [SIEVE] mail filtering language is a framework for providing notifications by employing URIs to specify the notification mechanism. This document defines how xmpp URIs (see [XMPP-URI]) are used to generate notifications via the Extensible Messaging and Presence Protocol (see [XMPP]), which is widely implemented in Jabber technologies. 1.2. Terminology This document inherits terminology from [NOTIFY], [SIEVE], and [XMPP]. The capitalized key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [TERMS]. 2. Definition The xmpp mechanism results in the sending of an XMPP message to notify a recipient about an email message. The general XMPP syntax is as follows: o The notification MUST be an XMPP stanza. o The value of the XMPP 'type' attribute MUST be 'headline' or 'normal'. o The value of the XMPP 'from' attribute MUST be the XMPP address of the notification service. o The XMPP stanza MAY include a child element whose value is some configurable text indicating that the message is a Sieve notification. o The notification SHOULD include a URL for the recipient to use as a hint in locating the message, encapsulated as the XML character data of a child element of an element qualified by the 'jabber:x:oob' namespace as specified in [JEP-0066]. The recommended mapping of the Sieve notify action into XMPP syntax is described in the following sections. 2.1. Notify tag ":method" The ":method" tag MUST be a URI that conforms to the xmpp URI scheme (as specified in [XMPP-URI]) and that identifies an XMPP account Saint-Andre & Melnikov Expires January 22, 2007 [Page 3] Internet-Draft SIEVE-XMPP July 2006 associated with the email inbox. The URI MAY include the resource identifier portion of an XMPP address but SHOULD NOT include an authority component, query component, or fragment identifier component. The processing application MUST extract an XMPP address from the URI in accordance with the processing rules specified in [XMPP-URI]. The resulting XMPP address MUST be encapsulated in XMPP syntax as the value of the XMPP 'to' attribute. 2.2. Notify tag ":from" The ":from" tag has no special meaning for this notification mechanism, and this specification puts no restriction on its use. As noted, the value of the XMPP 'from' attribute specified in the XMPP notification message MUST be the XMPP address of the notification service itself. The value of the ":from" tag MAY be transformed into XMPP syntax; if so, it SHOULD be encapsulated as the value of an [JEP-0131] header named "Reply-To". 2.3. Notify tag ":options" The ":options" tag has no special meaning for this notification mechanism. Any handling of this tag is the responsibility of an implementation. 2.4. Notify tag ":priority" The ":priority" tag has no special meaning for this notification mechanism, and this specification puts no restriction on its use. The value of the ":priority" tag MAY be transformed into XMPP syntax; if so, it MUST be encapsulated as the value of an [JEP-0131] header named "Urgency", and the XML character of that header MUST be "high" if the value of the ":priority" tag is "1", "medium" if the value of the ":priority" tag is "2", or "low" if the value of the ":priority" tag is "3". 2.5. Notify tag ":message" If included, the ":message" tag SHOULD be transformed into the XML character data of an XMPP element. If not included, the rule specified in [NOTIFY] SHOULD be followed, as shown in the examples below. 3. Examples In the following examples, the sender of the email has an address of , the entity to be notified has an XMPP address of , and the notification service has Saint-Andre & Melnikov Expires January 22, 2007 [Page 4] Internet-Draft SIEVE-XMPP July 2006 an XMPP address . The following is a basic Sieve notify action with only a method: notify :method "xmpp:romeo@example.com" The resulting XMPP stanza might be as follows: A Sieve instant notification! <juliet@example.org> Wherefore art thou? The following is a more advanced Sieve notify action with a method, priority, and message, as well as a URL pointing to the message: notify :method "xmpp:romeo@example.com" :priority "1" :message "Contact Juliet immediately!" The resulting XMPP stanza might be as follows: A Sieve instant notification! Contact Juliet immediately!
high
 imap://romeo@example.com/INBOX;UIDVALIDITY=385759045/;UID=20 4. Internationalization Considerations Although an XMPP address may contain nearly any [UNICODE] character, the value of the ":method" tag MUST be a Uniform Resource Identifier (see [URI]) rather than an Internationalized Resource Identifier (see [IRI]). The rules specified in [XMPP-URI] MUST be followed when generating XMPP URIs. Saint-Andre & Melnikov Expires January 22, 2007 [Page 5] Internet-Draft SIEVE-XMPP July 2006 In accordance with Section 13 of RFC 3920, all data sent over XMPP MUST be encoded in [UTF-8]. 5. Security Considerations Depending on the information included, sending a notification can be comparable to forwarding mail to the notification recipient. Care must be taken when forwarding mail automatically, to ensure that confidential information is not sent into an insecure environment. In particular, implementations MUST conform to the security considerations given in [NOTIFY], [SIEVE], and [XMPP]. 6. References 6.1. Normative References [JEP-0066] Saint-Andre, P., "Out of Band Data", JSF JEP 0066, January 2006. [JEP-0131] Saint-Andre, P. and J. Hildebrand, "Stanza Headers and Internet Metadata", JSF JEP 0131, August 2005. [NOTIFY] Melnikov, A., "Sieve Extension: Notifications", draft-ietf-sieve-notify-03 (work in progress), June 2006. [SIEVE] Showalter, T. and P. Guenther, "Sieve: An Email Filtering Language", draft-ietf-sieve-3028bis-06 (work in progress), March 2006. [TERMS] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [XMPP-URI] Saint-Andre, P., "Internationalized Resource Identifiers (IRIs) and Uniform Resource Identifiers (URIs) for the Extensible Messaging and Presence Protocol (XMPP)", draft-saintandre-xmpp-iri-04 (work in progress), March 2006. 6.2. Informative References [IRI] Duerst, M. and M. Suignard, "Internationalized Resource Identifiers (IRIs)", RFC 3987, January 2005. Saint-Andre & Melnikov Expires January 22, 2007 [Page 6] Internet-Draft SIEVE-XMPP July 2006 [UNICODE] The Unicode Consortium, "The Unicode Standard, Version 3.2.0", 2000. The Unicode Standard, Version 3.2.0 is defined by The Unicode Standard, Version 3.0 (Reading, MA, Addison- Wesley, 2000. ISBN 0-201-61633-5), as amended by the Unicode Standard Annex #27: Unicode 3.1 (http://www.unicode.org/reports/tr27/) and by the Unicode Standard Annex #28: Unicode 3.2 (http://www.unicode.org/reports/tr28/). [URI] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, January 2005. [UTF-8] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD 63, RFC 3629, November 2003. [XMPP] Saint-Andre, P., "Extensible Messaging and Presence Protocol (XMPP): Core", RFC 3920, October 2004. Saint-Andre & Melnikov Expires January 22, 2007 [Page 7] Internet-Draft SIEVE-XMPP July 2006 Authors' Addresses Peter Saint-Andre Jabber Software Foundation Email: stpeter@jabber.org Alexey Melnikov Isode Limited Email: Alexey.Melnikov@isode.com Saint-Andre & Melnikov Expires January 22, 2007 [Page 8] Internet-Draft SIEVE-XMPP July 2006 Intellectual Property Statement The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. 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Disclaimer of Validity This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Copyright Statement Copyright (C) The Internet Society (2006). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. Acknowledgment Funding for the RFC Editor function is currently provided by the Internet Society. Saint-Andre & Melnikov Expires January 22, 2007 [Page 9]