Network Working Group T. Showalter Internet Draft: Sieve: Vacation Extension Carnegie Mellon Document: draft-showalter-sieve-vacation-01.txt February 24, 1999 Expire in six months Sieve: Vacation Extension Status of this memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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 The protocol discussed in this document is experimental and subject to change. Persons planning on either implementing or using this protocol are STRONGLY URGED to get in touch with the author before embarking on such a project. Copyright Copyright (C) The Internet Society 1999. All Rights Reserved. Abstract This document describes an extension to the Sieve mail filtering language for an autoresponder similar to that of the Unix "vacation" command for replying to messages with certain safety features to prevent problems. Showalter Expire in Six Months [Page 1]
Internet DRAFT Sieve: Vacation Extension February 24, 1999 0. Meta-information on this draft This information is intended to facilitate discussion. It will be removed when this document leaves the Internet-Draft stage. 0.1. Discussion This draft is intended to be an extension to the Sieve mail filtering language, avaliable from the Internet-Drafts repository as <ftp://ftp.ietf.org/internet-drafts/draft-showalter-sieve-07.txt> (where 07 is the version number, which is actually currently 07). This draft and the Sieve language itself are being discussed on the MTA Filters mailing list at <ietf-mta-filters@imc.org>. Subscription requests can be sent to <ietf-mta-filters-request@imc.org> (send an email message with the word "subscribe" in the body). More information on the mailing list along with a WWW archive of back messages is available at <http://www.imc.org/ietf-mta-filters/>. 1. Introduction This is an extension to the Sieve language defined by [SIEVE] for notification that messages will not be immediately answered. Conventions for notations are as in [SIEVE] section 1.1, including use of [KEYWORDS]. 2. Capability Identifier Sieve implementations that implement vacation have an identifier of "vacation" for use with the capability mechanism. 3. Vacation Action Syntax: vacation [":days" number] [":addresses" string-list] [":subject" string] <reason: string> The "vacation" action implements a vacation autoresponder similar to the vacation command available under many versions of Unix. Its purpose is to provide correspondents with notification that the user is away for an extended period of time and that they should not expect quick responses. "Vacation" is used to respond to a message with another message. Vacation's messages are always addressed to the Return-Path address (that is, the envelope from address) of the message being responded to. Showalter Expire in Six Months [Page 2]
Internet DRAFT Sieve: Vacation Extension February 24, 1999 The ":days" argument is used to specify the period in which addresses are kept and are not responded to, and is always specified in days. The minimum value used for this parameter is 1. Sites MAY define a different minimum value. Sites MAY also define a maximum days value, which MUST be greater than 7, and SHOULD be greater than 30. If ":days" is omitted, the default value is 7, or the minimum value (as defined above), whichever is greater. If the parameter given to ":days" is greater than the minimum value, then the minimum value is used instead. If ":days" exceeds the site-defined maximum, the site-defined maximum is used instead. "Vacation" keeps track of all of the addresses that it has responded to in some period (as specified by the :days optional argument). If vacation has not previously responded to this address within that time period, it sends the "reason" argument to the Return-Path address of the message that is being responded to. "Vacation" never responds to a message unless the user's email address is in the "To" or "Cc" line of the original message. Implementations are assumed to be able to know this information, but users may have additional addresses beyond the control of the local mail system. Users can supply additional mail addresses that are theirs with the ":addresses" argument, which takes a string-list listing additional addresses that a user might have. Users can specify the subject of the reply with the ":subject" parameter. If the :subject parameter is not supplied, then the subject is generated as follows: The subject is set to the characters "Re: " followed by the original subject with all leading occurrence of the characters "Re: " stripped off. Replies must have the In-Reply-To field set to the Message-ID of the original message. Example: require "vacation"; vacation :days 23 :addresses ["tjs@znic.edu", "ts4z@landru.edu"] "I'm away until October 19. If it's an emergency, call 911, I guess." ; By mingling vacation with other rules, users can do something more selective. Showalter Expire in Six Months [Page 3]
Internet DRAFT Sieve: Vacation Extension February 24, 1999 Example: require "vacation"; if header :contains "from" "boss@frobnitzm.edu" { redirect "pleeb@xanadu.wv.us"; } else { vacation "Sorry, I'm away, I'll read your message when I get around to it."; } 4. Interaction with Other Sieve Actions Vacation does not affect the implicit keep. Vacation may not be used with reject. 5. Security Considerations It is critical that implementations correctly implement the limitations described above: Replies MUST NOT be sent out in response to messages not sent directly to the user, and replies MUST NOT be sent out more often than the :days argument states. 6. Author's Address Tim Showalter Carnegie Mellon University 5000 Forbes Avenue Pittsburgh, PA 15213 E-Mail: tjs+@andrew.cmu.edu Showalter Expire in Six Months [Page 4]
Internet DRAFT Sieve: Vacation Extension February 24, 1999 Appendix A. References [KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, Harvard University, March 1997. [SIEVE] Showalter, T., "Sieve: A Mail Filtering Language", Carnegie Mellon, Work in Progress. Appendix B. Full Copyright Statement Copyright (C) The Internet Society 1999. All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS 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. This document will expire before 31 July 1999. Showalter Expire in Six Months [Page 5]
