IMAP Extensions Working Group R. Gellens Internet-Draft QUALCOMM Incorporated Expires: January 16, 2005 C. Daboo ISAMET, Inc. July 18, 2004 IMAP ANNOTATE Extension draft-ietf-imapext-annotate-10 Status of this Memo By submitting this Internet-Draft, I certify that any applicable patent or other IPR claims of which I am aware have been disclosed, and any of which I become aware will be disclosed, in accordance with RFC 3668. 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 16, 2005. Copyright Notice Copyright (C) The Internet Society (2004). All Rights Reserved. Abstract The ANNOTATE extension to the Internet Message Access Protocol [IMAP4] permits clients and servers to maintain "metadata" for messages stored in an IMAP4 mailbox. Change History (to be removed prior to publication as an RFC) Changes from -09 to -10: Gellens & Daboo Expires January 16, 2005 [Page 1] Internet-Draft IMAP ANNOTATE Extension July 2004 1. Added Content-Language value. 2. Added IANA registrations for entries/attributes in this document. Changes from -08 to -09: 1. Fix formatting, ID nits etc. 2. Fix subject -> altsubject in examples. 3. Added text to SELECT/EXAMINE optional parameter definition to indicate that the option could trigger a global state change or a mailbox specific change. 4. Changed entry/attribute names to be case-sensitive to avoid case mapping issues with utf8 text. 5. Clarify COPY interaction to indicate that only the current user's '.priv's are copied, not the '.priv's of other users. Changes from -07 to -08: 1. ANNOTATESIZE response changed to use "NIL" for a mailbox that does not support any type of annotations, and "0" for a mailbox that only supports read-only annotations. Changes from -06 to -07: 1. Added text to state entry and attribute names are always case-insensitive. 2. Removed top-level entry namespace. 3. Added server accept minima for annotation size and count. 4. Added [ANNOTATE TOOBIG] & [ANNOTATE TOOMANY] response codes. 5. Added [ANNOTATESIZE <>] response code. 6. Added comment on suggested CONDSTORE support. 7. Modified append behaviour to account for MULTIAPPEND. 8. Tweaked ABNF. Changes from -05 to -06: 1. Split references into Normative and Informative. 2. Reworked flags to allow IMAP4 flag prefix to appear in annotation name. 3. Removed smtp-envelope annotation - a future extension can add this. 4. Changed subject to altsubject. 5. Added $MDNSent flag and reference to document. 6. Cleaned up formal syntax to use IMAP string type for entry and attributes, with requirements on how the string is formatted. 7. Use of ACAP vendor subtree registry for vendor tokens. 8. Fixed STORE syntax. Changes from -04 to -05: 1. Fixed examples to match formal syntax for FETCH responses where parenthesis do not appear around entry-att items. Changes from -03 to -04: Gellens & Daboo Expires January 16, 2005 [Page 2] Internet-Draft IMAP ANNOTATE Extension July 2004 1. Fixed attrib/attrib-match grammar to use "." instead of "/". 2. Add text for server to reject unknown . 3. Do not allow empty part-specifier. 4. Store NIL to value to delete. 5. Comment on COPY interaction with ANNOTATE. 6. Added comment that IMAP flags are mapped one-to-one with their corresponding FLAGS items. 7. Added comment that the recent flag annotation is read-only. Changes from -02 to -03: 1. Removed reference to status modtime item. 2. Added missing 'notify' and 'ret' dsn annotations for /message/ smtp-envelope. 3. Added requirement to store data permanently - no 'session only' annotations. 4. Removed Access Control section. Replaced with comments on read-only/read-write mailboxes and storing private or shared annotations. 5. Removed STORE to default .priv or .shared. 6. Added section on optional select parameters. Changes from -01 to -02: 1. Now require .priv or .shared on store operations. Changes from -00 to -01: 1. MODTIME moved to its own draft, which this draft now depends on. Thus, Conditional Annotation STORE and related items deleted from this draft. 2. Private versus Shared Annotations: both are possible (separately addressable using ".priv" and ".shared" suffixes). There is a per-mailbox setting for the default. It is an open issue how this is viewed or changed by the client. 3. In ACLs, the "w" right is needed to updated shared state; the "s" right is needed to update private state. 4. Various clarifications and text modifications. 5. Added 'forwarded' flag for message parts. Changes from pre-imapext to -00: 1. Clarified text describing attributions, entries, and attributes. 2. Changed 'modifiedsince' to 'modtime'; referenced ACAP spec. 3. Deleted 'queued' flag. 4. Expanded and explained smtp-envelope entry. 5. Restricted including ANNOTATION data in unsolicited responses until the client uses it first. (Open issue as to if needed). 6. Examples now only use valid entries and attributes. 7. Updated Security Considerations. 8. Content-Type now defaults to text/plain. Gellens & Daboo Expires January 16, 2005 [Page 3] Internet-Draft IMAP ANNOTATE Extension July 2004 9. Open Issue: Shared vs. private annotations. 10. Open issue: Annotation Modtime untagged response or VALIDTIME FETCH data. 11. Open issue: Conditional annotation STORE. 12. ANNOTATION criterion available if both "ANNOTATE" and "SORT" in CAPABILITY command response. 13. Prohibition on annotations in lieu of base spec functionality. 14. Specified required ACL rights. 15. ANNOTATION message data item in APPEND. 16. ANNOTATION-MODTIME message data item in STATUS. 17. Replaced ATOM_CHAR with utf8-char. 18. Updated other ABNF entries. Table of Contents 1. Introduction and Overview . . . . . . . . . . . . . . . . . 6 2. Data Model . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . 7 2.2 Namespace of entries and attributes . . . . . . . . . . . 7 2.2.1 Entry Names . . . . . . . . . . . . . . . . . . . . . 8 2.2.2 Attribute Names . . . . . . . . . . . . . . . . . . . 10 2.3 Private versus Shared and Access Control . . . . . . . . . 11 3. IMAP Protocol Changes . . . . . . . . . . . . . . . . . . . 12 3.1 General Considerations . . . . . . . . . . . . . . . . . . 12 3.2 Optional parameters with the SELECT/EXAMINE commands . . . 12 3.3 ANNOTATION Message Data Item in FETCH Command . . . . . . 14 3.4 ANNOTATION Message Data Item in FETCH Response . . . . . . 16 3.5 ANNOTATION Message Data Item in STORE . . . . . . . . . . 17 3.6 ANNOTATION interaction with COPY . . . . . . . . . . . . . 19 3.7 ANNOTATION Message Data Item in APPEND . . . . . . . . . . 19 3.8 ANNOTATION Criterion in SEARCH . . . . . . . . . . . . . . 19 3.9 ANNOTATION Key in SORT . . . . . . . . . . . . . . . . . . 20 4. Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . 21 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . 23 5.1 Entry and Attribute Registration Template . . . . . . . . 23 5.2 Entry Registrations . . . . . . . . . . . . . . . . . . . 23 5.2.1 /comment . . . . . . . . . . . . . . . . . . . . . . . 24 5.2.2 /flags/\answered . . . . . . . . . . . . . . . . . . 24 5.2.3 /flags/\flagged . . . . . . . . . . . . . . . . . . . 25 5.2.4 /flags/\deleted . . . . . . . . . . . . . . . . . . . 25 5.2.5 /flags/\seen . . . . . . . . . . . . . . . . . . . . 26 5.2.6 /flags/\draft . . . . . . . . . . . . . . . . . . . . 26 5.2.7 /flags/\recent . . . . . . . . . . . . . . . . . . . 27 5.2.8 /flags/$mdnsent . . . . . . . . . . . . . . . . . . . 27 5.2.9 /flags/$redirected . . . . . . . . . . . . . . . . . . 28 5.2.10 /flags/$forwarded . . . . . . . . . . . . . . . . . 28 5.2.11 /altsubject . . . . . . . . . . . . . . . . . . . . 29 5.2.12 //comment . . . . . . . . . . . . . . 29 Gellens & Daboo Expires January 16, 2005 [Page 4] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.13 //flags/seen . . . . . . . . . . . . . 30 5.2.14 //flags/answered . . . . . . . . . . . 30 5.2.15 //flags/flagged . . . . . . . . . . . 31 5.2.16 //flags/forwarded . . . . . . . . . . 31 5.3 Attribute Registrations . . . . . . . . . . . . . . . . . 31 5.3.1 value . . . . . . . . . . . . . . . . . . . . . . . . 32 5.3.2 size . . . . . . . . . . . . . . . . . . . . . . . . . 32 5.3.3 content-type . . . . . . . . . . . . . . . . . . . . . 33 5.3.4 content-language . . . . . . . . . . . . . . . . . . . 33 6. Security Considerations . . . . . . . . . . . . . . . . . . 33 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 34 7.1 Normative References . . . . . . . . . . . . . . . . . . . . 34 7.2 Informative References . . . . . . . . . . . . . . . . . . . 34 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 35 A. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 35 Intellectual Property and Copyright Statements . . . . . . . 36 Gellens & Daboo Expires January 16, 2005 [Page 5] Internet-Draft IMAP ANNOTATE Extension July 2004 1. Introduction and Overview The ANNOTATE extension is present in any IMAP4 implementation which returns "ANNOTATE" as one of the supported capabilities in the CAPABILITY response. The ANNOTATE extension adds a new message data item to the FETCH and STORE commands, as well as adding SEARCH and SORT keys and an APPEND modifier. This extension makes the following changes to the IMAP4 protocol: a. adds a new ANNOTATION message data item for use in FETCH b. adds a new ANNOTATION message data item for use in STORE c. adds a new ANNOTATION search criterion for use in SEARCH d. adds a new ANNOTATION sort key for use in SORT extension e. adds a new ANNOTATION data item for use in APPEND f. adds a new requirement on the COPY command g. adds a extension mechanism for adding parameters to the SELECT/ EXAMINE commands and defines the ANNOTATE parameter h. adds two new response codes to indicate store failures of annotations. i. adds a new untagged response codes for the SELECT or EXAMINE commands to indicate the maximum size. The data model used for the storage of annotations is based on that of the Application Configuration Access Protocol [ACAP]. Note that there is no inheritance in annotations. Clients MUST NOT use annotations in lieu of equivalent IMAP base specification facilities. For example, use of a "seen" flag in the vendor namespace together with ".PEEK" in fetches. Such behaviour would significantly reduce IMAP interoperability. If a server supports annotations, then it MUST store all annotation data permanently, i.e. there is no concept of 'session only' annotations that would correspond to the behaviour of 'session' flags as defined in the IMAP base specification. The exception to this is IMAP flags (which are accessible directly through annotations) which may be 'session only' as determined by the FLAGS and PERMANENTFLAGS responses to a SELECT or EXAMINE command. This extension also introduces a generalised mechanism for adding parameters to the SELECT or EXAMINE commands. It is anticipated that other extensions may want to utilise this, so it is not strictly dependent on the ANNOTATE extension being present. In order to provide optimum support for a disconnected client (one Gellens & Daboo Expires January 16, 2005 [Page 6] Internet-Draft IMAP ANNOTATE Extension July 2004 that needs to synchronise annotations for use when offline), servers SHOULD also support the Conditional STORE [CONDSTORE] extension. The rest of this document describes the data model and protocol changes more rigorously. 2. Data Model 2.1 Overview The data model used in ANNOTATE is that of a uniquely named entry which contains a set of standard attributes. A single coherent unit of "metadata" for a message is stored as a single entry, made up of several attributes. For example, a comment added to a message has an entry name of "/ comment". This entry is composed of several attributes such as "value", "size", etc. which contain the properties and data of the entry. The protocol changes to IMAP described below allow a client to access or change the values of any attributes in any entries in a message annotation, assuming it has sufficient access rights to do so (see Section 2.3 for specifics). 2.2 Namespace of entries and attributes Each message annotation is made up of a set of entries. Each entry has a hierarchical name in UTF-8, with each component of the name separated by a slash ("/"). Each entry is made up of a set of attributes. Each attribute has a hierarchical name in UTF-8, with each component of the name separated by a period ("."). The value of an attribute is NIL (has no value), or is a string of zero or more octets. Entry and attribute names MUST NOT contain asterisk ("*") or percent ("%") characters and MUST be valid UTF-8 strings which do not contain the NULL octet. Invalid entry or attribute names result in a BAD response in any IMAP commands where they are used. Entry and attribute names are case-sensitive. Use of non-visible UTF-8 characters in entry and attribute names is strongly discouraged. Gellens & Daboo Expires January 16, 2005 [Page 7] Internet-Draft IMAP ANNOTATE Extension July 2004 This specification defines an initial set of entry and attribute names available for use in message annotations. In addition, an extension mechanism is described to allow additional names to be added for extensibility. 2.2.1 Entry Names Entry names MUST be specified in a standards track or IESG approved experimental RFC, or fall under the vendor namespace. See Section 5.1 for the registration template. / Defines the top-level of entries associated with an entire message. This entry itself does not contain any attributes. All entries that start with a numeric character ("0" - "9") refer to an annotation on a specific body part. All other entries are for annotations on the entire message. /comment Defines a comment or note associated with an entire message. /flags Defines the top-level of entries for flags associated with an entire message. The "value" attribute of each of the entries described below must be either "1", "0" or NIL. "1" corresponds to the flag being set. Standard [IMAP4] flags always have a '\' prefix character. Other standard flags have a '$' prefix. The annotation names used for all flags uses the complete name for that flag, including the prefix character. The set of standard IMAP flags annotations are: /flags/\answered /flags/\flagged /flags/\deleted /flags/\seen /flags/\draft /flags/\recent Changes to these annotations are reflected in the standard IMAP flags. The \recent attribute is read only, clients MUST NOT attempt to change it. Note that entry names are sent as [IMAP4] string elements which requires that '\' characters be escaped if sent as a quoted string as opposed to a literal. Gellens & Daboo Expires January 16, 2005 [Page 8] Note that flag and keyword names in [IMAP4] are case-insensitive, however the entry names for the corresponding annotations are case-sensitive. Thus the [IMAP4] flag and keyword names MUST be mapped to lowercase characters before being used as entry names for annotations. Additional standard flags are: /flags/$mdnsent /flags/$redirected /flags/$forwarded The '$mdnsent' flag is used to indicate message disposition notification processing state [MDNSENT]. The '$redirected' flag indicates that a message has been handed off to someone else, by resending the message with minimal alterations, and in such a way that a reply by the new recipient is addressed to the original author, not the user who performed the redirection. The '$forwarded' flag indicates the message was resent to another user, embedded within or attached to a new message. /altsubject Contains text supplied by the message recipient, to be used by the client instead of the original message Subject. /vendor/ Defines the top-level of entries associated with an entire message as created by a particular product of some vendor. These sub-entries can be used by vendors to provide client-specific attributes. The vendor-token MUST be registered with IANA, using the [ACAP] vendor subtree registry. / Defines the top-level of entries associated with a specific body part of a message. This entry itself does not contain any attributes. The section-part uses the same numeric part specifier syntax as the BODY message data item in the FETCH command [IMAP4]. The server MUST return a BAD response if the client uses an incorrect part specifier (either incorrect syntax or a specifier referring to a non-existent part). The server MUST return a BAD response if the client uses an empty part specifier (which is used in [IMAP4] to represent the entire message). //comment Defines a comment or note associated with a specific body part of a message. Gellens & Daboo Expires January 16, 2005 [Page 9] Internet-Draft IMAP ANNOTATE Extension July 2004 //flags Defines the top-level of entries associated with flag state for a specific body part of a message. All sub-entries are maintained entirely by the client. There is no implicit change to any flag by the server. //flags/seen //flags/answered //flags/flagged //flags/forwarded Defines flags for a specific body part of a message. The "value" attribute of these entries must be either "1", "0" or NIL. //vendor/ Defines the top-level of entries associated with a specific body part of a message as created by a particular product of some vendor. This entry can be used by vendors to provide client specific attributes. The vendor-token MUST be registered with IANA. 2.2.2 Attribute Names Attribute names MUST be specified in a standards track or IESG approved experimental RFC, or fall under the vendor namespace. See Section 5.1 for the registration template. All attribute names implicitly have a ".priv" and a ".shared" suffix which maps to private and shared versions of the entry. Searching or fetching without using either suffix includes both. The client MUST specify either a ".priv" or ".shared" suffix when storing an annotation. value A UTF8 string representing the data value of the attribute. To delete an annotation, the client can store NIL into the value. size The size of the value, in octets. Set automatically by the server, read-only to clients. content-type A MIME [MIME] content type and subtype that describes the nature of the content of the "value" attribute. If not present, a value of "text/plain; charset=utf8" is assumed. content-language Gellens & Daboo Expires January 16, 2005 [Page 10] Internet-Draft IMAP ANNOTATE Extension July 2004 Indicates the language used for the value. This follows the format described in [RFC3282]. Clients SHOULD set this value when storing an annotation that uses text that can be presented to the user. It is not required for enumerated or numeric values such as flags etc. vendor. Defines an attribute associated with a particular product of some vendor. This attribute can be used by vendors to provide client specific attributes. The vendor-token MUST be registered with IANA, using the [ACAP] vendor subtree registry. 2.3 Private versus Shared and Access Control Some IMAP mailboxes are private, accessible only to the owning user. Other mailboxes are not, either because the owner has set an ACL [ACL] which permits access by other users, or because it is a shared mailbox. This raises the issue of shared versus private annotations. If all annotations are private, it is impossible to set annotations in a shared or otherwise non-private mailbox that are visible to other users. This eliminates what could be a useful aspect of annotations in a shared environment. An example of such use is a shared IMAP folder containing bug reports. Engineers may want to use annotations to add information to existing messages, indicate assignments, status, etc. This use requires shared annotations. If all annotations are shared, it is impossible to use annotations for private notes on messages in shared mailboxes. Also, modifying an ACL to permit access to a mailbox by other users may unintentionally expose private information. There are also situations in which both shared and private annotations are useful. For example, an administrator may want to set shared annotations on messages in a shared folder, which individual users may wish to supplement with additional notes. If shared and private annotations are to coexist, we need a clear way to differentiate them. Also, it should be as easy as possible for a client to access both and not overlook either. There is also a danger in allowing a client to store an annotation without knowing if it is shared or private. This document proposes two standard suffixes for all attributes: ".shared" and ".priv". A search, fetch, or sort which specifies neither uses both. Store operations MUST explicitly use .priv or Gellens & Daboo Expires January 16, 2005 [Page 11] Internet-Draft IMAP ANNOTATE Extension July 2004 .shared suffixes. A user can only store and fetch private annotations on messages in any mailbox which they can SELECT or EXAMINE, including ones which only open READ-ONLY. A user can only store and fetch shared annotations on messages in any mailbox that they can SELECT and which opens READ-WRITE. If a client attempts to store or fetch a shared annotation on a READ-ONLY mailbox, the server MUST respond with a NO response. 3. IMAP Protocol Changes 3.1 General Considerations The server is allowed to impose limitations on the size of any one annotation or the total number of annotations for a single message. However, the server MUST accept a minimum annotation data size of at least 1024 bytes, and a minimum annotation count per message of at least 10. The server SHOULD indicate the maximum size for an annotation value by sending an untagged "ANNOTATESIZE" response during a SELECT or EXAMINE command. Clients MUST NOT store annotation values of a size greater than the amount indicated by the server in the "ANNOTATESIZE" response. In some cases, servers may be able to offer annotations on some mailboxes and not others, or may be able to provide only read-only annotations on some mailboxes. For mailboxes that cannot have annotations associated with them, the server MUST return an "ANNOTATESIZE" response with a value of "NIL" during the SELECT or EXAMINE command for that mailbox. Clients MUST NOT attempt to fetch or store annotations on any messages in a mailbox for which the "ANNOTATESIZE" response was "NIL". For mailboxes that can only have read-only annotations associated with them, the server MUST return an "ANNOTATESIZE" response with a value of "0" (zero) during the SELECT or EXAMINE command for that mailbox. Clients MUST NOT attempt to store annotations on any messages in a mailbox for which the "ANNOTATESIZE" response was zero. 3.2 Optional parameters with the SELECT/EXAMINE commands This extension adds the ability to include one or more parameters with the IMAP SELECT or EXAMINE commands, to turn on or off certain standard behaviour, or to add new optional behaviours required for a particular extension. There are two possible modes of operation: Gellens & Daboo Expires January 16, 2005 [Page 12] o A global state change where a single use of the optional parameter will effect the session state from that time on, irrespective of subsequent SELECT/EXAMINE commands. o A per-mailbox state change that will effect the session only for the duration of the new selected state. A subsequent SELECT/ EXAMINE without the optional parameter will cancel its effect for the newly selected mailbox. It is anticipated that other extensions may want to use this facility, so a generalised approach is given here. This facility is not dependent on the presence of the ANNOTATE extension - other extensions can use it with a server that does not implement ANNOTATE. Optional parameters to the SELECT or EXAMINE commands are added as a parenthesised list of atoms or strings, and appear after the mailbox name in the standard SELECT or EXAMINE command. The order of individual parameters is arbitrary. Individual parameters may consist of one or more atoms or strings in a specific order. If a parameter consists of more than one atom or string, it MUST appear in its own parenthesised list. Any parameter not defined by extensions that the server supports MUST be rejected with a NO response. Example: C: a SELECT INBOX (ANNOTATE) S: ... S: a OK SELECT complete In the above example, a single parameter is used with the SELECT command. Example: C: a EXAMINE INBOX (ANNOTATE (RESPONSES "UID Responses") CONDSTORE) S: ... S: a OK EXAMINE complete In the above example, three parameters are used with the EXAMINE command. The second parameter consists of two items: an atom followed by a quoted string. Example: C: a SELECT INBOX (BLURDYBLOOP) S: a NO Unknown parameter in SELECT command In the above example, a parameter not supported by the server is incorrectly used. Gellens & Daboo Expires January 16, 2005 [Page 13] Internet-Draft IMAP ANNOTATE Extension July 2004 The ANNOTATE extension defines a single optional select parameter "ANNOTATE", which is used to turn on unsolicited responses for annotations as described in Section 3.4. This option al parameter is results in a per-mailbox state change, i.e. it must be used in each SELECT/EXAMINE command in order to be effective, irrespective of whether it was used in a previous SELECT/EXAMINE during the same session. 3.3 ANNOTATION Message Data Item in FETCH Command This extension adds an ANNOTATION message data item to the FETCH command. This allows clients to retrieve annotations for a range of messages in the currently selected mailbox. ANNOTATION The ANNOTATION message data item, when used by the client in the FETCH command, takes an entry specifier and an attribute specifier. Example: C: a FETCH 1 (ANNOTATION ("/comment" "value")) S: * 1 FETCH (ANNOTATION ("/comment" ("value.priv" "My comment" "value.shared" "Group note"))) S: a OK Fetch complete In the above example, the content of the "value" attribute for the "/comment" entry is requested by the client and returned by the server. Since neither ".shared" nor ".priv" was specified, both are returned. "*" and "%" wildcard characters can be used in either specifier to match one or more characters at that position, with the exception that "%" does not match the hierarchy delimiter for the specifier it appears in (that is, "/" for an entry specifier or "." for an attribute specifier). Thus an entry specifier of "/%" matches entries such as "/comment" and "/altsubject", but not "/flags/ $redirected". Example: Gellens & Daboo Expires January 16, 2005 [Page 14] Internet-Draft IMAP ANNOTATE Extension July 2004 C: a FETCH 1 (ANNOTATION ("/*" ("value.priv" "size.priv"))) S: * 1 FETCH (ANNOTATION ("/comment" ("value.priv" "My comment" "size.priv" "10") "/altsubject" ("value.priv" "Rhinoceroses!" "size.priv" "13") "/vendor/foobar/label.priv" ("value.priv" "label43" "size.priv" "7") "/vendor/foobar/personality" ("value.priv" "Tallulah Bankhead" "size.priv" "17"))) S: a OK Fetch complete In the above example, the contents of the private "value" and "size" attributes for any entries in the "" hierarchy are requested by the client and returned by the server. Example: C: a FETCH 1 (ANNOTATION ("/%" "value.shared")) S: * 1 FETCH (ANNOTATION ("/comment" ("value.shared" "Patch Mangler") "/altsubject" ("value.shared" "Patches? We don't need no steenkin patches!"))) S: a OK Fetch complete In the above example, the contents of the shared "value" attributes for entries at the top level only of the "" hierarchy are requested by the client and returned by the server. Entry and attribute specifiers can be lists of atomic specifiers, so that multiple items of each type may be returned in a single FETCH command. Example: C: a FETCH 1 (ANNOTATION (("/comment" "/altsubject") "value.priv")) S: * 1 FETCH (ANNOTATION ("/comment" ("value.priv" "What a chowder-head") "/altsubject" ("value.priv" "How to crush beer cans"))) S: a OK Fetch complete In the above example, the contents of the private "value" attributes for the two entries "/comment" and "/altsubject" are requested by the client and returned by the server. Gellens & Daboo Expires January 16, 2005 [Page 15] Internet-Draft IMAP ANNOTATE Extension July 2004 3.4 ANNOTATION Message Data Item in FETCH Response The ANNOTATION message data item in the FETCH response displays information about annotations in a message. ANNOTATION parenthesised list The response consists of a list of entries, each of which has a list of attribute-value pairs. Example: C: a FETCH 1 (ANNOTATION ("/comment" "value")) S: * 1 FETCH (ANNOTATION ("/comment" ("value.priv" "My comment" "value.shared" NIL))) S: a OK Fetch complete In the above example, a single entry with a single attribute-value pair is returned by the server. Since the client did not specify a ".shared" or ".priv" suffix, both are returned. Only the private attribute has a value (the shared value is NIL). Example: C: a FETCH 1 (ANNOTATION (("/comment" "/altsubject") "value")) S: * 1 FETCH (ANNOTATION ("/comment" ("value.priv" "My comment" "value.shared" NIL) "/altsubject" ("value.priv" "My subject" "value.shared" NIL))) S: a OK Fetch complete In the above example, two entries each with a single attribute-value pair are returned by the server. Since the client did not specify a ".shared" or ".priv" suffix, both are returned. Only the private attributes have values; the shared attributes are NIL. Example: Gellens & Daboo Expires January 16, 2005 [Page 16] Internet-Draft IMAP ANNOTATE Extension July 2004 C: a FETCH 1 (ANNOTATION ("/comment" ("value" "size"))) S: * 1 FETCH (ANNOTATION ("/comment" ("value.priv" "My comment" "value.shared" NIL "size.priv" "10" "size.shared" "0"))) S: a OK Fetch complete In the above example, a single entry with two attribute-value pairs is returned by the server. Since the client did not specify a ".shared" or ".priv" suffix, both are returned. Only the private attributes have values; the shared attributes are NIL. Servers MUST NOT include ANNOTATION data in unsolicited responses unless the client used the ANNOTATE select parameter when it issued the last SELECT or EXAMINE command. This restriction avoids sending ANNOTATION data to a client unless the client explicitly asks for it. Servers SHOULD send ANNOTATION message data items in unsolicited FETCH responses if an annotation entry is changed by a third-party, and the ANNOTATE select parameter was used. This allows servers to keep clients updated with changes to annotations by other clients. 3.5 ANNOTATION Message Data Item in STORE ANNOTATION Sets the specified list of entries by adding or replacing the specified attributes with the values provided. Clients can use NIL for values of attributes it wants to remove from entries. The ANNOTATION message data item used with the STORE command has an implicit ".SILENT" behaviour. This means the server does not generate an untagged FETCH in response to the STORE command and assumes that the client updates its own cache if the command succeeds. If the server is unable to store an annotation because the size of its value is too large, the server MUST return a tagged NO response with a "[ANNOTATE TOOBIG]" response code. If the server is unable to store a new annotation because the maximum number of allowed annotations has already been reached, the server MUST return a tagged NO response with a "[ANNOTATE TOOMANY]" response code. Gellens & Daboo Expires January 16, 2005 [Page 17] Internet-Draft IMAP ANNOTATE Extension July 2004 Example: C: a STORE 1 ANNOTATION ("/comment" ("value.priv" "My new comment")) S: a OK Store complete In the above example, the entry "/comment" is created (if not already present) and the private attribute "value" with data set to "My new comment" is created if not already present, or replaced if it exists. Example: C: a STORE 1 ANNOTATION ("/comment" ("value.shared" NIL)) S: a OK Store complete In the above example, the shared "value" attribute of the entry "/ comment" is removed by storing NIL into the attribute. Multiple entries can be set in a single STORE command by listing entry-attribute-value pairs in the list. Example: C: a STORE 1 ANNOTATION ("/comment" ("value.priv" "Get tix Tuesday") "/altsubject" ("value.priv" "Wots On")) S: a OK Store complete In the above example, the entries "/comment" and "/altsubject" are created (if not already present) and the private attribute "value" is created for each entry if not already present, or replaced if they exist. Multiple attributes can be set in a single STORE command by listing multiple attribute-value pairs in the entry list. Example: C: a STORE 1 ANNOTATION ("/comment" ("value.priv" "My new comment" "vendor.foobar.priv" "foo's bar")) S: a OK Store complete In the above example, the entry "/comment" is created (if not already present) and the private attributes "value" and "vendor.foobar" are Gellens & Daboo Expires January 16, 2005 [Page 18] Internet-Draft IMAP ANNOTATE Extension July 2004 created if not already present, or replaced if they exist. 3.6 ANNOTATION interaction with COPY The COPY command can be used to move messages from one mailbox to another on the same server. Servers that support the ANNOTATION extension MUST, for each message being copied, copy all '.priv' annotation data for the current user only, and all '.shared' annotation data along with the message to the new mailbox. The only exceptions to this are if the destination mailbox permissions are such that either the '.priv' or '.shared' annotations are not allowed, or if the destination mailbox is of a type that does not support annotations or does not support storing of annotations (a mailbox that returns a zero or "NIL" value for its ANNOTATESIZE response code). Servers MUST NOT copy '.priv' annotation data for users other than the current user. 3.7 ANNOTATION Message Data Item in APPEND ANNOTATION Sets the specified list of entries and attributes in the resulting message. The APPEND command can include annotations for the message being appended via the addition of a new append data item. The new data item can also be used with the multi-append [MULTIAPPEND] extension that allows multiple messages to be appended via a single APPEND command. Example: C: a APPEND drafts ANNOTATION ("/comment" ("value.priv" "Don't send until we hear from Sally")) {310} S: + Ready for literal data C: MIME-Version: 1.0 ... C: S: a OK APPEND completed In the above example, a comment with a private value is added to a new message appended to the mailbox. The ellipsis represents the bulk of the message. 3.8 ANNOTATION Criterion in SEARCH ANNOTATION Gellens & Daboo Expires January 16, 2005 [Page 19] Internet-Draft IMAP ANNOTATE Extension July 2004 The ANNOTATION criterion for the SEARCH command allows a client to search for a specified string in the value of an annotation entry of a message. Messages that have annotations with entries matching and attributes matching and the specified string in their values are returned in the SEARCH results. The "*" character can be used in the entry or attribute name fields to match any content in those items. The "%" character can be used in the entry or attribute name fields to match a single level of hierarchy only. Example: C: a SEARCH ANNOTATION "/comment" "value" "IMAP4" S: * SEARCH 2 3 5 7 11 13 17 19 23 S: a OK Search complete In the above example, the message numbers of any messages containing the string "IMAP4" in the shared or private "value" attribute of the "/comment" entry are returned in the search results. Example: C: a SEARCH ANNOTATION "*" "*" "IMAP4" S: * SEARCH 1 2 3 5 8 13 21 34 S: a OK Search complete In the above example, the message numbers of any messages containing the string "IMAP4" in any attribute (public or private) of any entry are returned in the search results. 3.9 ANNOTATION Key in SORT ANNOTATION The ANNOTATION criterion for the SORT command [SORT] instructs the server to return the message numbers or UIDs of a mailbox, sorted using the values of the specified annotations. The ANNOTATION criterion is available if the server returns both "ANNOTATE" and "SORT" as supported capabilities in the CAPABILITY command response. Messages are sorted using the values of the attributes in the entries. (The charset argument determines sort order, as specified in the SORT extension description.) Gellens & Daboo Expires January 16, 2005 [Page 20] Internet-Draft IMAP ANNOTATE Extension July 2004 Example: C: a SORT (ANNOTATION "/altsubject" "value.shared") UTF-8 ALL S: * SORT 2 3 4 5 1 11 10 6 7 9 8 S: a OK Sort complete In the above example, the message numbers of all messages are returned, sorted according to the shared "value" attribute of the "/altsubject" entry. Note that the ANNOTATION sort key must include a fully specified entry and attribute -- wildcards are not allowed. 4. Formal Syntax The following syntax specification uses the Augmented Backus-Naur Form (ABNF) notation as specified in [ABNF]. Non-terminals referenced but not defined below are as defined by [IMAP4]. Except as noted otherwise, all alphabetic characters are case-insensitive. The use of upper or lower case characters to define token strings is for editorial clarity only. Implementations MUST accept these strings in a case-insensitive fashion. annotate-param = "ANNOTATE" ; defines the select parameter used with ; ANNOTATE extension append = "APPEND" SP mailbox [SP flag-list] [SP date-time] [SP "ANNOTATION" SP att-annotate] SP literal ; modifies original IMAP4 APPEND command append-message = [SP flag-list] [SP date-time] [SP "ANNOTATION" SP att-annotate] SP literal ; modifies [MULTIAPPEND] extension behaviour att-annotate = "ANNOTATION" SP "(" entry-att *(SP entry-att) ")" att-match = string ; dot-separated attribute name ; MAY contain "*" or "%" for use as wildcards att-value = attrib SP value attrib = string ; dot-separated attribute name Gellens & Daboo Expires January 16, 2005 [Page 21] Internet-Draft IMAP ANNOTATE Extension July 2004 ; MUST NOT contain "*" or "%" attribs = att-match / "(" att-match *(SP att-match) ")" entries = entry-match / "(" entry-match *(SP entry-match) ")" entry = string ; slash-separated path to entry ; MUST NOT contain "*" or "%" entry-att = entry SP "(" att-value *(SP att-value) ")" entry-match = string ; slash-separated path to entry ; MAY contain "*" or "%" for use as wildcards examine =/ *(SP "(" select-param *(SP select-param) ")" ; modifies the original IMAP4 examine command to ; accept optional parameters fetch-ann-resp = "ANNOTATION" SP "(" entry-att *(SP entry-att) ")" fetch-att =/ "ANNOTATION" SP "(" entries SP attribs ")" ; modifies original IMAP4 fetch-att resp-text-code =/ "ANNOTATE" SP "TOOBIG" / "ANNOTATE" SP "TOOMANY" / "ANNOTATESIZE" SP (number / "NIL") ; new response codes search-key =/ "ANNOTATION" SP entry-match SP att-match SP value ; modifies original IMAP4 search-key select =/ *(SP "(" select-param *(SP select-param) ")" ; modifies the original IMAP4 select command to ; accept optional parameters select-param = astring / "(" astring SP astring *(SP astring) ")" ; parameters to SELECT may contain one or ; more atoms or strings - multiple items ; are always parenthesised sort-key =/ "ANNOTATION" SP entry SP attrib ; modifies original sort-key [SORT] Gellens & Daboo Expires January 16, 2005 [Page 22] Internet-Draft IMAP ANNOTATE Extension July 2004 store-att-flags =/ att-annotate ; modifies original IMAP4 STORE command value = nstring 5. IANA Considerations Both entry names and attribute names MUST be specified in a standards track or IESG approved experimental RFC, or fall under the vendor namespace. Vendor names MUST be registered. 5.1 Entry and Attribute Registration Template To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [] Entry [] Attribute Name: ______________________________ Description: _______________________ ____________________________________ ____________________________________ Contact person: ____________________ email: ____________________ 5.2 Entry Registrations The following templates specify the IANA registrations of annotation entries specified in this document. Gellens & Daboo Expires January 16, 2005 [Page 23] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.1 /comment To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /comment Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.2 /flags/\answered To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/\answered Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 24] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.3 /flags/\flagged To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/\flagged Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.4 /flags/\deleted To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/\deleted Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 25] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.5 /flags/\seen To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/\seen Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.6 /flags/\draft To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/\draft Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 26] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.7 /flags/\recent To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/\recent Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.8 /flags/$mdnsent To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/$mdnsent Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 27] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.9 /flags/$redirected To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/$redirected Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.10 /flags/$forwarded To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /flags/$forwarded Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 28] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.11 /altsubject To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: /altsubject Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.12 //comment To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: //comment Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 29] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.13 //flags/seen To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: //flags/seen Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.14 //flags/answered To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: //flags/answered Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 30] Internet-Draft IMAP ANNOTATE Extension July 2004 5.2.15 //flags/flagged To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: //flags/flagged Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.2.16 //flags/forwarded To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [X] Entry [] Attribute Name: //flags/forwarded Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.3 Attribute Registrations The following templates specify the IANA registrations of annotation attributes specified in this document. Gellens & Daboo Expires January 16, 2005 [Page 31] Internet-Draft IMAP ANNOTATE Extension July 2004 5.3.1 value To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [] Entry [X] Attribute Name: value Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.3.2 size To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [] Entry [X] Attribute Name: size Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com Gellens & Daboo Expires January 16, 2005 [Page 32] Internet-Draft IMAP ANNOTATE Extension July 2004 5.3.3 content-type To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [] Entry [X] Attribute Name: content-type Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 5.3.4 content-language To: iana@iana.org Subject: IMAP Annotate Registration Please register the following IMAP Annotate item: [] Entry [X] Attribute Name: content-language Description: Defined in IMAP ANNOTATE extension document. Contact person: Cyrus Daboo email: daboo@isamet.com 6. Security Considerations Care must be taken to ensure that annotations whose values are intended to remain private are not stored in mailboxes which are accessible to other users. This includes mailboxes owned by the user by whose ACLs permit access by others as well as any shared mailboxes. Excluding the above issues the ANNOTATE extension does not raise any security considerations that are not present in the base [IMAP4] protocol, and these issues are discussed in [IMAP4]. Gellens & Daboo Expires January 16, 2005 [Page 33] Internet-Draft IMAP ANNOTATE Extension July 2004 7. References 7.1 Normative References [RFC1891] Moore, K., "SMTP Service Extension for Delivery Status Notifications", RFC 1891, January 1996. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. [RFC2244] Newman, C. and J. Myers, "ACAP -- Application Configuration Access Protocol", RFC 2244, November 1997. [RFC3282] Alvestrand, H., "Content Language Headers", RFC 3282, May 2002. [RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1", RFC 3501, March 2003. [RFC3502] Crispin, M., "Internet Message Access Protocol (IMAP) - MULTIAPPEND Extension", RFC 3502, March 2003. [RFC3503] Melnikov, A., "Message Disposition Notification (MDN) profile for Internet Message Access Protocol (IMAP)", RFC 3503, March 2003. [SORT] Crispin, M. and K. Murchison, "Internet Message Access Protocol - Sort and Thread Extension", draft-ietf-imapext-sort-17.txt, May 2004. 7.2 Informative References [CONDSTORE] Melnikov, A. and S. Hole, "IMAP Extension for Conditional STORE operation", draft-ietf-imapext-condstore-05.txt, November 2003. [RFC2086] Myers, J., "IMAP4 ACL extension", RFC 2086, January 1997. Gellens & Daboo Expires January 16, 2005 [Page 34] Internet-Draft IMAP ANNOTATE Extension July 2004 Authors' Addresses Randall Gellens QUALCOMM Incorporated 5775 Morehouse Dr. San Diego, CA 92121-2779 US EMail: randy@qualcomm.com Cyrus Daboo ISAMET, Inc. 5001 Baum Blvd. Suite 650 Pittsburgh, PA 15213 US EMail: daboo@isamet.com Appendix A. Acknowledgments Many thanks to Chris Newman for his detailed comments on the first draft of this document, and to the participants at the ACAP working dinner in Pittsburgh. Gellens & Daboo Expires January 16, 2005 [Page 35] Internet-Draft IMAP ANNOTATE Extension July 2004 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. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. 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 (2004). 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. Gellens & Daboo Expires January 16, 2005 [Page 36]