Network Working Group Jutta Degener Internet Draft Sendmail, Inc. Expires: July 2004 January 2004 Sieve -- "copy" extension Status of this memo This document is an Internet-Draft and is subject to 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/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html Abstract This document defines a new keyword parameter, ":copy", to be used with the sieve "fileinto" and "redirect" actions. The new parameter prevents cancellation of the implicit keep. 1. Introduction Some users have the notion of forwarding a copy of a message for safekeeping to another e-mail address, or of saving a copy in a folder -- in addition to the regular message delivery, which shouldn't be affected by the copy. If saving an extra copy is all the user wanted to do, fileinto "unfiltered"; keep; would do the job. But the explicit "keep" is a poor substitute for the implicit keep when more processing follows: fileinto "unfiltered"; keep; if header "Subject" "MAKE MONEY FAST!!!" { discard; } In this example, the "discard" is ineffective against the explicit "keep"; the discarded message still ends up in the user's inbox. It is possible to generate sieve code that perfectly expresses a user's wishes, but such code quickly grows unwieldy because it needs to keep track of the state the implicit keep would have had without the fileinto or redirect command. This extension tries to make life easier for user interface designers and script writers by allowing them to express the "copy" semantics directly. 2. Conventions used. Conventions for notations are as in [SIEVE] section 1.1, including use of [KEYWORDS] and "Syntax:" label for the definition of action and tagged arguments syntax. The capability string associated with extension defined in this document is "copy". 3. ":copy" extension to the "fileinto" and "redirect" command. Syntax: "fileinto" [":copy"] "redirect" [":copy"] If the optional :copy keyword is specified with "fileinto" or "redirect", the tagged command does not cancel the implicit keep. Instead, it merely files or redirects a copy in addition to whatever else is happening to the message. Example: require ["copy", "fileinto"]; fileinto :copy "unfiltered"; 4. Security Considerations The "copy" extension makes it easier to eavesdrop on a user's message stream without the user noticing. 5. IANA Considerations The following template specifies the IANA registration of the "copy" Sieve extension specified in this document. To: iana@iana.org Subject: Registration of new Sieve extension Capability name: copy Capability keyword: copy Capability arguments: N/A Standards Track/IESG-approved experimental RFC number: this RFC Person and email address to contact for further information: Jutta Degener Sendmail, Inc. 6425 Christie Ave, 4th Floor Emeryville, CA 94608 Email: jutta@sendmail.com This information should be added to the list of sieve extensions given on http://www.iana.org/assignments/sieve-extensions. 6. Acknowledgments Thanks to Eric Allman, Ned Freed, Will Lee, Nigel Swinson, and Rand Wacker for corrections and comments. 7. Author's Address Jutta Degener Sendmail, Inc. 6425 Christie Ave, 4th Floor Emeryville, CA 94608 Email: jutta@sendmail.com 8. Discussion This section will be removed when this document leaves the Internet-Draft stage. This draft is intended as an extension to the Sieve mail filtering language. Sieve extensions are discussed on the MTA Filters mailing list at . Subscription requests can be sent to (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 . 9.1 Changes from the previous version Added IANA considerations. Inserted Appendix B. Changed Appendix A "References" to "Normative References". Added brief example. Appendices Appendix A. Normative References [KEYWORDS] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997. [SIEVE] Showalter, T., "Sieve: A Mail Filtering Language", RFC 3028, January 2001. Appendix B. 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