Sieve Working Group                                             B. Leiba
Internet-Draft                                       Huawei Technologies
Intended status: Standards Track                        January 26,                      September 27, 2010
Expires: July 30, 2010 March 31, 2011

     Support for Sieve in Internet Message Access Protocol (IMAP4)
                     draft-ietf-sieve-imap-sieve-00
                     draft-ietf-sieve-imap-sieve-01

Abstract

   Sieve defines an email filtering language that can, in principle,
   plug into any point in the processing of an email message.  As
   defined in the base specification, it plugs into mail delivery.  This
   document defines how Sieve can plug into points in the IMAP protocol
   where messages are created or changed, adding the option of user-
   defined or installation-defined filtering (or, with Sieve extensions,
   features such as notifications).

Note

   This document defines extensions to IMAP and Sieve.  It is the work
   of the Sieve Working Group, but had previously been in the lemonade
   mailing list, as draft-ietf-lemonade-imap-sieve.

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Table of Contents

   1.      Introduction . . . . . . . . . . . . . . . . . . . . . . .  6
   1.1.    Overview . . . . . . . . . . . . . . . . . . . . . . . . .  6
   1.2.    Conventions used in this document  . . . . . . . . . . . .  6

   2.      The IMAP "IMAPSieve" Extension . . . . . . . . . . . . . .  7
   2.1.    The "IMAPSieve" Capability String  . . . . . . . . . . . .  7
   2.2.    Existing IMAP Functions Affected by IMAPSieve  . . . . . .  7
   2.2.1.  The IMAP APPEND Command  . . . . . . . . . . . . . . . . .  7
   2.2.2.  The IMAP MULTIAPPEND Command . . . . . . . . . . . . . . .  7
   2.2.3.  The IMAP COPY Command  . . . . . . . . . . . . . . . . . .  8
   2.2.4.  Changes to IMAP Message Flags  . . . . . . . . . . . . . .  8
   2.2.5.  New or Changed IMAP Message Annotations  . . . . . . . . .  8
   2.3.    New Functions Defined by IMAPSieve . . . . . . . . . . . .  9
   2.3.1.  Changes to Metadata  . . . . . . . . . . . . . . . . . . .  9

   3.      Applicable Sieve Actions and Interactions  . . . . . . . . 11
   3.1.    The Implicit Keep  . . . . . . . . . . . . . . . . . . . . 11
   3.2.    The Keep Action  . . . . . . . . . . . . . . . . . . . . . 11
   3.3.    The Fileinto Action  . . . . . . . . . . . . . . . . . . . 11
   3.4.    The Redirect Action  . . . . . . . . . . . . . . . . . . . 12
   3.5.    The Reject Action  . . . . . . . . . . . . . . . . . . . . 12
   3.6.    The Discard Action . . . . . . . . . . . . . . . . . . . . 12
   3.7.    The Notify Action  . . . . . . . . . . . . . . . . . . . . 13
   3.8.    The Addheader and Deleteheader Actions . . . . . . . . . . 13
   3.9.    The Setflag, Deleteflag, and Removeflag Actions  . . . . . 13
   3.10.   The Vacation Action  . . . . . . . . . . . . . . . . . . . 14
   3.11.   Spamtest . . . . . . . . . . . . . . . . . . . . . . . . . 14
   3.12.   New Sieve Environment Item: cause  . . . . . . . . . . . . 14
   3.13.   New Sieve Environment Item: mailbox  . . . . . . . . . . . 14
   3.14.   New Sieve Environment Item: changedflags . . . . . . . . . 15
   3.15.   New Sieve Environment Item: changedannotations . . . . . . 15
   3.16.   Interaction With Sieve Tests (Comparisons) . . . . . . . . 15

   4.      Examples . . . . . . . . . . . . . . . . . . . . . . . . . 16

   5.      Security Considerations  . . . . . . . . . . . . . . . . . 17

   6.      IANA Considerations  . . . . . . . . . . . . . . . . . . . 18
   6.1.    Registration of imapsieve extension  . . . . . . . . . . . 18
   6.2.    Registration of environment item: cause  . . . . . . . . . 18
   6.3.    Registration of environment item: mailbox  . . . . . . . . 18
   6.4.    Registration of environment item: changedflags . . . . . . 19
   6.5.    Registration of environment item: changedannotations . . . 19
   6.6.    Registration of IMAP METADATA mailbox entry name . . . . . 20
   6.7.    Registration of IMAP METADATA server entry name  . . . . . 20
   7.      References . . . . . . . . . . . . . . . . . . . . . . . . 22
   7.1.    Normative References . . . . . . . . . . . . . . . . . . . 22
   7.2.    Non-Normative References . . . . . . . . . . . . . . . . . 22

           Author's Address . . . . . . . . . . . . . . . . . . . . . 24

1.  Introduction

1.1.  Overview

   Some applications have a need to apply [Sieve] filters in situations
   other than initial mail delivery.  This is especially true in diverse
   service environments, such as when the client is sporadically
   connected, is connected through a high-latency or high-cost channel,
   or is on a limited-function device.  For such clients, it may be very
   important, for higher performance and reliability, to take advantage
   of server capabilities, including those provided by Sieve filtering
   (and Sieve extensions, such as [Notify]).

   This specification defines extensions to [IMAP] to support the
   invocation of Sieve scripts at times when the IMAP server creates new
   messages, or modifies existing ones.  It also defines how Sieve
   scripts will process these invocations.  Support for IMAPSieve
   requires support for [Metadata] as well, since the latter is used to
   associate scripts with IMAP mailboxes.

   [[anchor1: General note: Sieve was designed to work at final
   delivery, and makes many assumptions about the context.  Will those
   assumptions break this environment without our realizing it fully?]]

   [[anchor2: Note about identity: We might want to use Sieve to impose
   fine-grained access controls.  In final delivery, there's no identity
   for the "filer".  Here, there is: the logged-in IMAP user.  How do we
   get at that identity?]]

1.2.  Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "MAY", and "OPTIONAL" in this document are to
   be interpreted as described in [Keywds].

2.  The IMAP "IMAPSieve" Extension

2.1.  The "IMAPSieve" Capability String

   An IMAP server advertises support for this extension through the
   capability string "IMAPSieve" (the string is not case-sensitive, and
   is shown here with this capitalization for readability).  A server
   that advertises IMAPSieve is claiming to be in compliance with this
   specification in all aspects.

   Implementations that support IMAPSieve MUST also support
   [Environment], because the latter defines an important way for Sieve
   scripts to test the conditions under which they have been invoked.
   Notwithstanding this requirement, scripts that use IMAPSieve must
   include BOTH capability strings in their required lists.

2.2.  Existing IMAP Functions Affected by IMAPSieve

   The subsections below describe in detail the IMAP commands and
   situations on which IMAPSieve has an effect.  Not all Sieve actions
   make sense in the case of messages affected by IMAP commands.  See
   Section 3 for details.

   It's important to note that since the base Sieve specification (see
   [Sieve]) and its extensions define functions for scripts that are
   invoked during initial mail delivery, those function definitions are
   necessarily tailored to and limited by that context.  This document
   extends those function definitions for use during IMAP events.  By
   nature of that, Sieve functions, in this extended context, may behave
   somewhat differently, though their extended behaviour will still be
   consistent with the functions' goals.

   If more than one message is affected at the same time, each message
   triggers the execution of a Sieve script separately.  The scripts MAY
   be run in parallel.

2.2.1.  The IMAP APPEND Command

   A message may be added to a mailbox through the IMAP APPEND command.
   In a server that advertises IMAPSieve, new messages added in this way
   MUST trigger the execution of a Sieve script, subject to the settings
   defined through Metadata (see Section 2.3.1).

2.2.2.  The IMAP MULTIAPPEND Command

   If the IMAP server supports the IMAP [MultiAppend] extension,
   messages may be added to a mailbox through the IMAP MULTIAPPEND
   command.  In a server that advertises IMAPSieve, new messages added
   in this way MUST trigger the execution of a Sieve script, as with the
   APPEND command, also subject to the settings defined through
   Metadata.

2.2.3.  The IMAP COPY Command

   One or more messages may be added to a mailbox through the IMAP COPY
   command.  In a server that advertises IMAPSieve, new messages added
   in this way MUST trigger the execution of a Sieve script, subject to
   the settings defined through Metadata.

2.2.4.  Changes to IMAP Message Flags

   One or more existing messages can have their flags changed in a
   number of ways, including:

   o  The FETCH command (may cause the \Seen flag to be set).

   o  The STORE command (may cause the \Answered, \Deleted, \Draft,
      \Flagged, and \Seen flags to be set or reset, and may cause
      keywords to be set or reset).

   o  The invocation of a Sieve script on an existing message, where the
      Sieve implementation supports the [IMAP4Flags] extension and the
      script uses one of the actions defined in that extension.

   In a server that advertises IMAPSieve, messages whose flags are
   changed in any way (except as explained in the next sentence) MUST
   trigger the execution of a Sieve script, subject to the settings
   defined through Metadata.  The exception is that in order to avoid
   script loops, flag changes that are made as a result of a script that
   was itself invoked because of flag changes SHOULD NOT result in
   another script invocation.  In any case, implementations MUST take
   steps to avoid such loops.

   For flag-change events, the Sieve script will see the message flags
   as they are AFTER the changes.

2.2.5.  New or Changed IMAP Message Annotations

   [[anchor3: Sieve has no way to get the annotations, so is there
   really value in being told about annotation changes here?  Maybe push
   that into a sieve-annotations extension later.]]

   If the IMAP server supports the [Annotate] extension, one or more
   existing messages can have annotations added or changed through the
   ANNOTATE command.  In a server that advertises IMAPSieve, messages
   getting new or changed annotations MUST trigger the execution of a
   Sieve script, subject to the settings defined through Metadata.

   For annotation-change events, the Sieve script will see the message
   annotations as they are AFTER the changes.

2.3.  New Functions Defined by IMAPSieve

2.3.1.  Changes to Metadata

   Support for IMAPSieve requires support for [Metadata] as well, since
   the latter is used to associate scripts with IMAP mailboxes.

   When an applicable event occurs on an IMAP mailbox, if there is an
   IMAP metadata entry named "/IMAPSieve/Script" for the mailbox, that
   entry is used.  If there is not, but there is an IMAP metadata entry
   named "/IMAPSieve/Script" for the server, that entry is used
   (providing a way to define a global script for all mailboxes on a
   server).  If neither entry exists, then no script will be invoked.

   If an "/IMAPSieve/Script" metadata entry was selected above, the
   shared value of that metadata name (its "value.shared" attribute)
   MUST be the name of the Sieve script that will be invoked in response
   to the IMAP event OR the name of another metadata entry, the name
   prefixed with "metadata:" (such as "metadata:/IMAPSieve/
   ScriptContents"), that contains the actual script in its value.shared
   attribute.  Note that only the value.shared attribute is used; any
   value.priv attributes are ignored.

   This specifies the mechanism for "activating" a script for a given
   mailbox (or for all mailboxes), but does not specify a mechanism for
   creating, storing, or validating the script.  Implementations MAY use
   [Manage] to acomplish this, using the PUTSCRIPT command to store the
   script without using the SETACTIVE command to activate it.  In any
   case, the script name that is specified in the /IMAPSieve/Script
   metadata entry is in a form that depends upon how the server handles
   the storing of Sieve scripts.

   Only one Sieve script may currently be defined per mailbox,
   eliminating the complexity and possible ambiguity involved with
   coordinating the results of multiple scripts.  Any sub-filtering is
   done in the Sieve script.  For example, if it's only necessary to
   deal with flag changes, but not with new messages appended or copied,
   the Sieve script will still be invoked for all events, and the script
   is responsible for checking the event type.

   The possibility is open for an extensions to add support for multiple
   scripts -- for example, per-client scripts on a multi-client user's
   inbox, or per-user scripts on a mailbox that is shared among users.

   Because this metadata name is associated with the mailbox, there can
   (and it's expected that there will) be different scripts associated
   with events for different mailboxes.  Indeed, most mailboxes will
   probably invoke no script at all.

3.  Applicable Sieve Actions and Interactions

   Since some Sieve actions relate specifically to the delivery of mail,
   not all actions make sense when the messages are created by other
   means or when changes are made to data associated with existing
   messages.  This section describes how actions in the base Sieve
   specification, and those in extensions known at this writing, relate
   to this specification.

   In addition to what is specified here, interactions noted in the
   individual specifications apply, and must be considered.

3.1.  The Implicit Keep

   For all cases that fall under IMAPSieve, the implicit keep means that
   the message is treated as it would have been if no Sieve script were
   run.  For APPEND, MULTIAPPEND and COPY, the message is stored into
   the target mailbox normally.  For flag or annotation changes, the
   message is left in the mailbox.

3.2.  The Keep Action

   The keep action is applicable in all cases that fall under IMAPSieve.
   Its behaviour is as described for implicit keep, in Section 3.1.

3.3.  The Fileinto Action

   If the Sieve implementation supports the fileinto action, that action
   is applicable in all cases that fall under IMAPSieve.  If the [Copy]
   extension is available and the :copy option is specified, the
   implicit keep is retained; otherwise, fileinto cancels the implicit
   keep, as specified in the base Sieve specification.

   For APPEND, MULTIAPPEND, and COPY, the message is stored into the
   fileinto mailbox IN ADDITION TO the original target mailbox.  For
   flag or annotation changes, the message is COPIED into the fileinto
   mailbox, without removing the original.

   If a keep action is NOT also in effect, the original message is then
   marked with the \Deleted flag (and a flag-change Sieve script is NOT
   invoked).  The implementation MAY then expunge the original message
   (WITHOUT expunging other messages in the mailbox), or it MAY choose
   to have expunges batched, or done by a user.  If the server does the
   expunge, the effect is as though a client had flagged the message and
   done a UID EXPUNGE (see [UIDPlus]) on the affected message(s) only.
   Handling it this way allows clients to handle messages consistently,
   and avoids hidden changes that might invalidate their message caches.

3.4.  The Redirect Action

   [[anchor4: Redirect assumes message can be submitted as is - not a
   valid assumption in this context.  What do we do if the decision is
   "redirect" and there's not enough information to do it?  Also, some
   have been concerned about, say, a flag change that has the Sieve
   effect of forwarding the message somewhere.  Perhaps we should just
   forbid redirect.]]

   The redirect action is applicable in all cases that fall under
   IMAPSieve.  It causes the message to be sent, as specified in the
   base Sieve specification, to the designated address.  If the [Copy]
   extension is available and the :copy option is specified, the
   implicit keep is retained; otherwise, redirect cancels the implicit
   keep, as specified in the base Sieve specification.

   For APPEND, MULTIAPPEND, and COPY, the message is stored into the
   target mailbox in addition to being redirected.  For flag or
   annotation changes, the message remains in its original mailbox.

   If a keep action is NOT also in effect, the original message is then
   marked with the \Deleted flag (and a flag-change Sieve script is NOT
   invoked).  The implementation MAY then expunge the original message
   (WITHOUT expunging other messages in the mailbox), or it MAY choose
   to have expunges batched, or done by a user.  If the server does the
   expunge, the effect is as though a client had flagged the message and
   done a UID EXPUNGE (see [UIDPlus]) on the affected message(s) only.
   Handling it this way allows clients to handle messages consistently,
   and avoids hidden changes that might invalidate their message caches.

3.5.  The Reject Action

   The reject action is NOT applicable to any case that falls under
   IMAPSieve.  Its use MUST result in an error condition that will
   terminate the Sieve script.

3.6.  The Discard Action

   The discard action is applicable in all cases that fall under
   IMAPSieve.  For APPEND, MULTIAPPEND, and COPY, the message is first
   stored into the target mailbox.  If an explicit keep action is also
   in effect, the discard action now does nothing.  Otherwise, the
   original message is then marked with the \Deleted flag (and a flag-
   change Sieve script is NOT invoked).  The implementation MAY then
   expunge the original message (WITHOUT expunging other messages in the
   mailbox), or it MAY choose to have expunges batched, or done by a
   user.  If the server does the expunge, the effect is as though a
   client had flagged the message and done a UID EXPUNGE (see [UIDPlus])
   on the affected message(s) only.  Handling it this way allows clients
   to handle messages consistently, and avoids hidden changes that might
   invalidate their message caches.

3.7.  The Notify Action

   If the [Notify] extension is available, the notify action is
   applicable in all cases that fall under IMAPSieve.  The result is
   that the requested notification is sent, and that the message is
   otherwise handled as it would normally have been.

3.8.  The Addheader and Deleteheader Actions

   [[anchor5: Should editheader be allowed to change header fields that
   aren't saved in place, such as for redirect or fileinto?  Editheader
   would still have to be banned for "keep", but not otherwise.]]

   Even if the [EditHeader] extension is available, since messages in
   IMAP mailboxes are immutable these actions are NOT applicable.  Use
   of these MUST result in an error condition that will terminate the
   Sieve script.  Explanation: Using them for flag or annotation changes
   to existing messages would cause the message to be changed.  Using
   them for APPEND, MULTIAPPEND, and COPY would cause unexpected
   differences in the stored copy as compared to what the client
   expected, and would make the client's message cache invalid
   unexpectedly.

3.9.  The Setflag, Deleteflag, and Removeflag Actions

   [[anchor6: Should this just require imap4flags?  Some implementors
   have said they wouldn't bother with it without the ability to
   manipulate flags.  And what values of flags does it see -- before or
   after the change?  If it changes them, can it see the originals?  Can
   it reset changes?]]

   If the [IMAP4Flags] extension is available, the actions associated
   with it are all applicable to any case that falls under IMAPSieve.
   It is worth noting also that the "hasflag" test that is defined in
   the IMAP4Flags extension might be particularly useful in scripts
   triggered by flag changes ("hasflag" will see the new, changed
   flags).  The flag changes behave as though a client had made the
   change.

   As explained above, in order to avoid script loops flag changes that
   are made as a result of a script that was itself invoked because of
   flag changes SHOULD NOT result in another script invocation.  In any
   case, implementations MUST take steps to avoid such loops.

3.10.  The Vacation Action

   Even if the [Vacation] extension is available, the vacation action is
   NOT applicable to any case that falls under IMAPSieve.  Its use MUST
   result in an error condition that will terminate the Sieve script.

3.11.  Spamtest

   [Spamtest] [[anchor7: We need to say something about the spamtest/
   virustest extension.  We need to be able to scan appended messages.
   And we can't use headers to communicate spam status, because the
   message is immutable.  What should we say here?]]

3.12.  New Sieve Environment Item: cause

   Implementations MAY invoke different Sieve scripts for the different
   conditions described in this document (append, copy, flag changes,
   annotation changes).  If the actions to be taken are common, and the
   implementation supports the [Include] extension, the common script
   code can be included as specified there.

   It may be preferable, though, to use a single script for all these
   conditions.  To support that, the implementation MUST set the
   [Environment] item "cause", which contains the name of the action
   that caused the script to be invoked.  Its value is one of the
   following:

   o  APPEND (for invocations resulting from APPEND or MULTIAPPEND)

   o  COPY (for invocations resulting from COPY)

   o  FLAG (for invocations resulting from flag changes)

   o  ANNOTATE (for invocations resulting from new or changed
      annotations)

3.13.  New Sieve Environment Item: mailbox

   The implementation MUST set the [Environment] item "mailbox" to the
   name of the mailbox that the affected message is in, in the case of
   existing messages, or is targeted to be stored into, in the case of
   new messages.  The value of this item is fixed when the script
   begins, and, in particular, MUST NOT change as a result of any
   action, such as "fileinto".

3.14.  New Sieve Environment Item: changedflags

   If the [IMAP4Flags] extension is available, AND the script was
   invoked because of flag changes to an existing message, the
   implementation MUST set the [Environment] item "changedflags" to the
   name(s) of the flag(s) that have changed.  If the script was not
   invoked because of flag changes, the value of this item MUST be the
   empty string.  The script will not know from this item whether the
   flags have been set or reset, but it can use the "hasflag" test to
   determine the current value.  See example 2 in Section 4 for an
   example of how this might be used.

3.15.  New Sieve Environment Item: changedannotations

   If the [Annotate] extension is available, AND the script was invoked
   because of annotation changes to an existing message, the
   implementation MUST set the [Environment] item "changedannotations"
   to the name(s) of the annotation(s) that have changed.  If the script
   was not invoked because of annotation changes, the value of this item
   MUST be the empty string.

3.16.  Interaction With Sieve Tests (Comparisons)

   This extension does not affect the operation of any tests or
   comparisons.

4.  Examples

   Example 1:
   If a new message is added to the "ActionItems" mailbox, a copy is
   sent to the address "actionitems@example.com".

     require ["copy", "environment"];

     if anyof (environment :is "cause" "APPEND",
               environment :is "cause" "COPY")  {
         if environment :is "mailbox" "ActionItems" {
             redirect :copy "actionitems@example.com";
         }
     }

   Example 2:
   If the script is called for any message with the \Flagged flag set
   (tested through the [IMAP4Flags] extension), a notification is sent
   using the [Notify] extension.  No notification will be sent, though,
   if we're called with an existing message that already had that flag
   set.

     require ["notify", "imap4flags", "variables", "environment"];

     if environment :matches "mailbox" "*" {
         set "mailbox" "${1}";
     }

     if allof (hasflag "\\Flagged",
               not environment :contains "changedflags" "\\Flagged") {
         notify :message "Important message in ${mailbox}";
     }

5.  Security Considerations

   It is possible to introduce script processing loops by having a Sieve
   script that is triggered by flag changes use the actions defined in
   the [IMAP4Flags] extension.  Implementations MUST take steps to
   prevent such loops.  One way to avoid this problem is that if a
   script is invoked by flag changes, and that script further changes
   the flags, those flag changes SHOULD NOT trigger a Sieve script
   invocation.

   Other security considerations are discussed in [IMAP], and [Sieve],
   as well as in some of the other extension documents.

6.  IANA Considerations

6.1.  Registration of imapsieve extension

   The following template specifies the IANA registration of the Sieve
   extension specified in this document:

   To: iana@iana.org
   Subject: Registration of new Sieve extension
   Capability name: imapsieve
   Description: Add Sieve processing for IMAP events.
   RFC number: this RFC
   Contact address: Barry Leiba <barryleiba@computer.org>

   This information should be added to the list of sieve extensions
   given on http://www.iana.org/assignments/sieve-extensions.

6.2.  Registration of environment item: cause

   The following template specifies the IANA registration of a sieve
   environment item specified in this document:

   To: iana@iana.org
   Subject: Registration of new Sieve environment item
   Item name: cause
   Description: The name of the action that caused the script to be
   invoked.  Its value is one of the following:

   o  APPEND (for invocations resulting from APPEND or MULTIAPPEND)

   o  COPY (for invocations resulting from COPY)

   o  FLAG (for invocations resulting from flag changes)

   o  ANNOTATE (for invocations resulting from new or changed
      annotations)

   RFC number: this RFC
   Contact address:
       Barry Leiba <barryleiba@computer.org>

   This information should be added to the list of sieve environment
   item names given in the [Environment] extension.

6.3.  Registration of environment item: mailbox

   The following template specifies the IANA registration of a sieve
   environment item specified in this document:

   To: iana@iana.org
   Subject: Registration of new Sieve environment item
   Item name: mailbox
   Description: The name of the mailbox that the affected message is in,
   in the case of existing messages, or is targeted to be stored into,
   in the case of new messages.  The value of this item is fixed when
   the script begins, and, in particular, MUST NOT change as a result of
   any action, such as "fileinto".
   RFC number: this RFC
   Contact address:
       Barry Leiba <barryleiba@computer.org>

   This information should be added to the list of sieve environment
   item names given in the [Environment] extension.

6.4.  Registration of environment item: changedflags

   The following template specifies the IANA registration of a sieve
   environment item specified in this document:

   To: iana@iana.org
   Subject: Registration of new Sieve environment item
   Item name: changedflags
   Description: If the script was invoked because of flag changes to an
   existing message, this contains the name(s) of the flag(s) that have
   changed.  Otherwise, the value of this item MUST be the empty string.
   RFC number: this RFC
   Contact address:
       Barry Leiba <barryleiba@computer.org>

   This information should be added to the list of sieve environment
   item names given in the [Environment] extension.

6.5.  Registration of environment item: changedannotations

   The following template specifies the IANA registration of a sieve
   environment item specified in this document:

   To: iana@iana.org
   Subject: Registration of new Sieve environment item
   Item name: changedannotations
   Description: If the script was invoked because of annotation changes
   to an existing message, this contains the name(s) of the
   annotation(s) that have changed.  Otherwise, the value of this item
   MUST be the empty string.
   RFC number: this RFC
   Contact address:
       Barry Leiba <barryleiba@computer.org>

   This information should be added to the list of sieve environment
   item names given in the [Environment] extension.

6.6.  Registration of IMAP METADATA mailbox entry name

   The following template specifies the IANA registration of an IMAP
   METADATA entry name specified in this document:

   To: iana@iana.org
   Subject: IMAP METADATA Registration
   Please register the following IMAP METADATA item:
   [x] Entry           [ ] Attribute
   [x] Mailbox         [ ] Server
   Name: /IMAPSieve/Script
   Description: This entry name is used to define mailbox metadata
   associated with IMAPSieve events for the associated mailbox.
   Specifically, this specifies the Sieve script that will be invoked
   when IMAP events occur on the specified mailbox.
   Content-type: text/plain; charset=utf-8
   RFC number: this RFC
   Contact person: Barry Leiba
   Contact email: barryleiba@computer.org

   This information should be added to the list of IMAP METADATA item
   names given in the [Metadata] extension.

6.7.  Registration of IMAP METADATA server entry name

   The following template specifies the IANA registration of an IMAP
   METADATA entry name specified in this document:

   To: iana@iana.org
   Subject: IMAP METADATA Registration
   Please register the following IMAP METADATA item:
   [x] Entry           [ ] Attribute
   [ ] Mailbox         [x] Server
   Name: /IMAPSieve/Script
   Description: This entry name is used to define metadata associated
   globally with IMAPSieve events for the associated server.
   Specifically, this specifies the Sieve script that will be invoked
   when IMAP events occur on any mailbox in the server that does not
   have its own mailbox-level /IMAPSieve/Script entry.
   Content-type: text/plain; charset=utf-8
   RFC number: this RFC
   Contact person: Barry Leiba
   Contact email: barryleiba@computer.org

   This information should be added to the list of IMAP METADATA item
   names given in the [Metadata] extension.

7.  References

7.1.  Normative References

   [Annotate]
              Daboo, C. and R. Gellens, "IMAP ANNOTATE Extension",
              RFC 5257, June 2008.

   [Copy]     Degener, J., "Sieve Extension: Copying Without Side
              Effects", RFC 3894, October 2004.

   [Environment]
              Freed, N., "Sieve Email Filtering: Environment Extension",
              RFC 5183, May 2008.

   [IMAP]     Crispin, M., "Internet Message Access Protocol - Version
              4rev1", RFC 3501, March 2003.

   [IMAP4Flags]
              Melnikov, A., "Sieve Mail Filtering Language: IMAP flag
              Extension", RFC 5232, January 2008.

   [Keywds]   Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", RFC 2119, March 1997.

   [Metadata]
              Daboo, C., "The IMAP METADATA Extension", RFC 5464,
              February 2009.

   [MultiAppend]
              Crispin, M., "Internet Message Access Protocol (IMAP) -
              MULTIAPPEND Extension", RFC 3502, March 2003.

   [Sieve]    Guenther, P., Ed. and T. Showalter, Ed., "Sieve: An Email
              Filtering Language", RFC 5228, January 2008.

7.2.  Non-Normative References

   [EditHeader]
              Degener, J. and P. Guenther, "Sieve Email Filtering:
              Editheader Extension", RFC 5293, August 2008.

   [Include]  Daboo, C. and A. Stone, "SIEVE Email Filtering: Include
              Extension", work in progress, http://tools.ietf.org/html/
              draft-ietf-sieve-include, July 2009.

   [Manage]   Melnikov, A., Ed. and T. Martin, "A Protocol for Remotely
              Managing Sieve Scripts", RFC editor queue, http://
              tools.ietf.org/html/draft-ietf-sieve-managesieve,
              January 2009.

   [Notify]   Melnikov, A., Ed., Leiba, B., Ed., Segmuller, W., and T.
              Martin, "Sieve Email Filtering: Extension for
              Notifications", RFC 5435, January 2009.

   [Spamtest]
              Daboo, C., "Sieve Email Filtering: Spamtest and Virustest
              Extensions", RFC 5235, January 2008.

   [UIDPlus]  Crispin, M., "Internet Message Access Protocol (IMAP) -
              UIDPLUS Extension", RFC 4315, December 2005.

   [Vacation]
              Showalter, T. and N. Freed, Ed., "Sieve Email Filtering:
              Vacation Extension", RFC 5230, January 2008.

Author's Address

   Barry Leiba
   Huawei Technologies

   Phone: +1 646 827 0648
   Email: barryleiba@computer.org
   URI:   http://internetmessagingtechnology.org/