:orphan:

.. _imap-rfc-support:

============================
RFCs Supported by Cyrus IMAP
============================

The following is an inventory of RFCs supported by Cyrus IMAP.

:rfc:`822`

    Standard for the format of ARPA Internet text messages, obsoleted by
    :rfc:`2822`.

:rfc:`0977`

    Network News Transfer Protocol

:rfc:`1036`

    Standard for interchange of USENET messages

:rfc:`1176`

    Interactive Mail Access Protocol: Version 2

:rfc:`1342`

    Representation of Non-ASCII Text in Internet Message Headers

:rfc:`1652`

    SMTP Service Extension for 8bit-MIMEtransport

:rfc:`1730`

    Internet Message Access Protocol - version 4, obsoleted by
    :rfc:`2060`, :rfc:`2061`, :rfc:`3501`.

:rfc:`1869`

    SMTP Service Extensions

:rfc:`1870`

    SMTP Service Extension for Message Size Declaration

:rfc:`1939`

    Post Office Protocol - Version 3 (POP3)

:rfc:`1951`

    DEFLATE Compressed Data Format Specification version 1.3

:rfc:`1952`

    GZIP file format specification version 4.3

:rfc:`2033`

    Local Mail Transfer Protocol

:rfc:`2034`

    SMTP Service Extension for Returning Enhanced Error Codes

:rfc:`2045`

    Multipurpose Internet Mail Extensions (MIME) Part One: Format of
    Internet Message Bodies

:rfc:`2046`

    Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types

:rfc:`2047`

    MIME (Multipurpose Internet Mail Extensions) Part Three: Message
    Header Extensions for Non-ASCII Text

:rfc:`2060`

    Internet Message Access Protocol - Version 4rev1, obsoleted by
    :rfc:`3501`.

:rfc:`2086`

    IMAP4 ACL Extension, obsoleted by :rfc:`4314`.

    .. NOTE::

        Backwards compatibility with this RFC is to be obsoleted.

:rfc:`2087`

    IMAP4 QUOTA extension

:rfc:`2088`

    IMAP4 non-synchronizing literals

:rfc:`2177`

    IMAP4 IDLE command

:rfc:`2192`

    IMAP URL Scheme, obsoleted by
    :rfc:`5092`.

:rfc:`2193`

    IMAP4 Mailbox Referrals

:rfc:`2195`

    IMAP/POP AUTHorize Extension for Simple Challenge/Response

:rfc:`2246`

    The TLS Protocol Version 1.0

:rfc:`2298`

    Extensible Message Format for Message Disposition Notifications
    (MDNs)

:rfc:`2342`

    IMAP4 Namespace

:rfc:`2359`

    IMAP4 UIDPLUS extension, obsoleted by :rfc:`4315`

:rfc:`2425`

    A MIME Content-Type for Directory Information

    .. NOTE::

	See the comment behind RFC 6352 below.

:rfc:`2426`

    vCard MIME Directory Profile

    .. NOTE::

	See the comment behind RFC 6352 below.

:rfc:`2444`

    The One-Time-Password SASL Mechanism

:rfc:`2449`

    POP3 Extension Mechanism

:rfc:`2518`

    HTTP Extensions for Distributed Authoring -- WEBDAV

:rfc:`2595`

    Using TLS with IMAP, POP3 and ACAP

:rfc:`2617`

    HTTP Authentication: Basic and Digest Access Authentication,
    updated by :rfc:`7615`, :rfc:`7616`, :rfc:`7617`.

:rfc:`2817`

    HTTP Upgrading to TLS Within HTTP/1.1

:rfc:`2818`

    HTTP Over TLS

:rfc:`2821`

    Simple Mail Transfer Protocol

:rfc:`2822`

    Internet Message Format

:rfc:`2831`

    Using Digest Authentication as a SASL Mechanism

:rfc:`2920`

    SMTP Service Extension for Command Pipelining

:rfc:`2971`

    IMAP4 ID extension

:rfc:`2980`

    Common NNTP Extensions

:rfc:`3028`

    Sieve: A Mail Filtering Language

:rfc:`3206`

    The SYS and AUTH POP Response Codes

:rfc:`3207`

    SMTP Service Extension for Secure SMTP over TLS

:rfc:`3253`

    Versioning Extensions to WebDAV (Web Distributed Authoring and
    Versioning)

:rfc:`3339`

    Date and Time on the Internet: Timestamps

:rfc:`3348`

    IMAP4 Child Mailbox Extension

:rfc:`3431`

    Sieve Extension: Relational Tests

:rfc:`3463`

    Enhanced Mail System Status Codes

:rfc:`3501`

    Internet Message Access Protocol - version 4rev1

:rfc:`3502`

    IMAP MULTIAPPEND extension

:rfc:`3516`

    IMAP4 Binary Content Extension

:rfc:`3598`

    Sieve Email Filtering -- Subaddress Extension, obsoleted by
    :rfc:`5233`.

:rfc:`3656`

    MUPDATE Protocol (For Cyrus Murder)

:rfc:`3691`

    Internet Message Access Protocol (IMAP) UNSELECT command

:rfc:`3744`

    Web Distributed Authoring and Versioning (WebDAV) Access Control
    Protocol

:rfc:`3834`

    Recommendations for Automatic Responses to Electronic Mail

:rfc:`3848`

    ESMTP and LMTP Transmission Types Registration

:rfc:`3894`

    Sieve Extension: Copying Without Side Effects

:rfc:`3977`

    Network News Transfer Protocol (NNTP)

:rfc:`4287`

    The Atom Syndication Format

:rfc:`4314`

    IMAP4 Access Control List (ACL) Extension

:rfc:`4315`

    Internet Message Access Protocol (IMAP) - UIDPLUS extension

:rfc:`4331`

    Quota and Size Properties for Distributed Authoring and Versioning
    (DAV) Collections

:rfc:`4346`

    The Transport Layer Security (TLS) Protocol Version 1.1

:rfc:`4422`

    Simple Authentication and Security Layer (SASL)

:rfc:`4466`

    Collected Extensions to IMAP4 ABNF

:rfc:`4467`

    Internet Message Access Protocol (IMAP) - URLAUTH Extension, updated
    by :rfc:`5092`.

:rfc:`4469`

    Internet Message Access Protocol (IMAP) CATENATE Extension

:rfc:`4505`

    Anonymous Simple Authentication and Security Layer (SASL) Mechanism

:rfc:`4550`

    Internet Email to Support Diverse Service Environments (Lemonade)
    Profile

:rfc:`4551`

    IMAP Extension for Conditional STORE Operation or Quick Flag Changes
    Resynchronization

:rfc:`4559`

    SPNEGO-based Kerberos and NTLM HTTP Authentication in Microsoft
    Windows

:rfc:`4616`

    The PLAIN Simple Authentication and Security Layer (SASL) Mechanism

:rfc:`4642`

    Using Transport Layer Security (TLS) with Network News Transfer
    Protocol (NNTP)

:rfc:`4643`

    Network News Transfer Protocol (NNTP) Extension for Authentication

:rfc:`4644`

    Network News Transfer Protocol (NNTP) Extension for Streaming Feeds

:rfc:`4731`

    IMAP4 Extension to SEARCH Command for Controlling What Kind of
    Information Is Returned

:rfc:`4791`

    Calendaring Extensions to WebDAV (CalDAV)

:rfc:`4918`

    HTTP Extensions for Web Distributed Authoring and Versioning
    (WebDAV)

:rfc:`4954`

    SMTP Service Extension for Authentication

:rfc:`4959`

    IMAP Extension for Simple Authentication and Security Layer (SASL)
    Initial Client Response

:rfc:`4978`

    The IMAP COMPRESS Extension

:rfc:`5032`

    WITHIN Search Extension to the IMAP Protocol

:rfc:`5034`

    The Post Office Protocol (POP3) Simple Authentication and Security
    Layer (SASL) Authentication Mechanism

:rfc:`5092`

    IMAP URL Scheme, updated by :rfc:`5593`.

:rfc:`5161`

    The IMAP ENABLE Extension

:rfc:`5162`

    IMAP4 Extensions for Quick Mailbox Resynchronization

:rfc:`5173`

    Sieve Email Filtering: Body Extension

:rfc:`5183`

    Sieve Email Filtering: Environment Extension

:rfc:`5228`

    Sieve: A Mail Filtering Language

:rfc:`5229`

    Sieve Email Filtering: Variables Extension

:rfc:`5230`

    Sieve Email Filtering: Vacation Extension

:rfc:`5231`

    Sieve Email Filtering: Relational Extension

:rfc:`5232`

    Sieve Email Filtering: Imap4flags Extension

    .. versionadded:: 2.5.0

:rfc:`5233`

    Sieve Email Filtering: Subaddress Extension

:rfc:`5235`

    Sieve Email Filtering: Spamtest and Virustest Extensions

:rfc:`5256`

    Internet Message Access Protocol - SORT and THREAD Extensions

:rfc:`5257`

    Internet Message Access Protocol - ANNOTATE Extension

:rfc:`5258`

    Internet Message Access Protocol version 4 - LIST Command Extensions

:rfc:`5260`

    Sieve Email Filtering: Date and Index Extensions

    .. versionadded:: 2.5.0

:rfc:`5267`

    Contexts for IMAP4

    .. NOTE::

        The ESORT capability is implemented.  The CONTEXT=SEARCH and
        CONTEXT=SORT capabilities are not implemented.

:rfc:`5293`

    Sieve Email Filtering: Editheader Extension

:rfc:`5321`

    Simple Mail Transfer Protocol

:rfc:`5322`

    Internet Message Format

    .. NOTE::

       The JMAP mapping is incomplete.

:rfc:`5397`

    WebDAV Current Principal Extension

:rfc:`5423`

    Internet Message Store Events

:rfc:`5429`

    Sieve Email Filtering: Reject and Extended Reject Extensions

:rfc:`5435`

    Sieve Email Filtering: Extension for Notifications

:rfc:`5436`

    Sieve Notification Mechanism: mailto

:rfc:`5463`

    Sieve Email Filtering: Ihave Extension

:rfc:`5464`

    The IMAP METADATA Extension

:rfc:`5490`

    The Sieve Mail-Filtering Language -- Extensions for Checking Mailbox
    Status and Accessing Mailbox Metadata

:rfc:`5524`

    Extended URLFETCH for Binary and Converted Parts

:rfc:`5536`

    Netnews Article Format

:rfc:`5537`

    Netnews Architecture and Protocols

:rfc:`5545`

    Internet Calendaring and Scheduling Core Object Specification
    (iCalendar)

:rfc:`5546`

    iCalendar Transport-Independent Interoperability Protocol (iTIP)

:rfc:`5593`

    Internet Message Access Protocol (IMAP) - URL Access Identifier
    Extension

:rfc:`5689`

    Extended MKCOL for Web Distributed Authoring and Versioning (WebDAV)

:rfc:`5703`

    Sieve Email Filtering: MIME Part Tests, Iteration, Extraction,
    Replacement, and Enclosure

:rfc:`5804`

    A protocol for Remotely Managing Sieve Scripts

:rfc:`5819`

    IMAP4 Extension for Returning STATUS Information in Extended LIST

:rfc:`5957`

    Display-Based Address Sorting for the IMAP4 SORT Extension

:rfc:`5995`

    Using POST to Add Members to Web Distributed Authoring and
    Versioning (WebDAV) Collections

:rfc:`6009`

    Sieve Email Filtering: Delivery Status Notifications and
    Deliver-By Extensions

:rfc:`6047`

    iCalendar Message-Based Interoperability Protocol (iMIP)

:rfc:`6101`

    The Secure Sockets Layer (SSL) Protocol Version 3.0

    .. NOTE::

        SSLv3 is considered insecure as it is vulnerable to POODLE.

        Support for SSLv3 is being deprecated and removed.

:rfc:`6131`

    Sieve Vacation Extension: "Seconds" Parameter

:rfc:`6134`

    Sieve Extension: Externally Stored Lists

:rfc:`6154`

    IMAP LIST Extension for Special-Use Mailboxes

    .. NOTE::

        The LIST and LSUB commands return the special-use flags, unless the
	``specialusealways`` configuration variable is explicitly turned off.

:rfc:`6203`

    IMAP4 Extension for Fuzzy Search

:rfc:`6321`

    xCal: The XML Format for iCalendar

:rfc:`6350`

    vCard Format Specification

    .. NOTE::

	See the comment behind RFC 6352 below.

:rfc:`6352`

    CardDAV: vCard Extensions to Web Distributed Authoring and
    Versioning (WebDAV)

    .. NOTE::

       Cyrus IMAP accepts over CardDAV both vCard 3.0 and vCard 4.0, but
       does not advertise over CARDDAV:supported-address-data vCard 4.0
       support, announces only vCard 3.0.  Moreover, Cyrus IMAP does not
       convert between vCard 3.0 and vCard 4.0.  It is applications’
       responsibility not to misinterpret the vCard version and damage
       the data.

:rfc:`6376`

    DomainKeys Identified Mail (DKIM) Signatures

:rfc:`6558`

    Sieve Extension for Converting Messages before Delivery

:rfc:`6455`

    The WebSocket Protocol

:rfc:`6578`

    Collection Synchronization for Web Distributed Authoring and
    Versioning (WebDAV)

:rfc:`6585`

    Additional HTTP Status Codes

:rfc:`6609`

    Sieve Email Filtering: Include Extension

:rfc:`6638`

    Scheduling Extensions to CalDAV

:rfc:`6764`

    Locating Services for Calendaring Extensions to WebDAV (CalDAV) and
    vCard Extensions to WebDAV (CardDAV)

:rfc:`6797`

    HTTP Strict Transport Security (HSTS)

:rfc:`6851`

    Internet Message Access Protocol (IMAP) - MOVE Extension

    .. versionadded:: 2.5.0

:rfc:`6901`

    JavaScript Object Notation (JSON) Pointer

:rfc:`7230`

    Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing

:rfc:`7231`

    Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content

:rfc:`7232`

    Hypertext Transfer Protocol (HTTP/1.1): Conditional Requests

:rfc:`7233`

    Hypertext Transfer Protocol (HTTP/1.1): Range Requests

:rfc:`7234`

    Hypertext Transfer Protocol (HTTP/1.1): Caching

:rfc:`7235`

    Hypertext Transfer Protocol (HTTP/1.1): Authentication

:rfc:`7238`

    The Hypertext Transfer Protocol Status Code 308 (Permanent Redirect)

:rfc:`7239`

    Forwarded HTTP Extension

:rfc:`7240`

    Prefer Header for HTTP

:rfc:`7265`

    jCal: The JSON Format for iCalendar

:rfc:`7352`

    Sieve Email Filtering: Detecting Duplicate Deliveries

:rfc:`7529`

    Non-Gregorian Recurrence Rules in the Internet Calendaring and
    Scheduling Core Object Specification (iCalendar)

:rfc:`7540`

    Hypertext Transfer Protocol Version 2 (HTTP/2)

:rfc:`7615`

    HTTP Authentication-Info and Proxy-Authentication-Info Response
    Header Fields

:rfc:`7616`

    HTTP Digest Access Authentication

:rfc:`7617`

    The 'Basic' HTTP Authentication Scheme

:rfc:`7692`

    Compression Extensions for WebSocket

:rfc:`7694`

    Hypertext Transfer Protocol (HTTP) Client-Initiated Content-Encoding

:rfc:`7725`

    An HTTP Status Code to Report Legal Obstacles

:rfc:`7804`

    Salted Challenge Response HTTP Authentication Mechanism

:rfc:`7808`

    Time Zone Data Distribution Service

:rfc:`7809`

    CalDAV: Time Zones by Reference

:rfc:`7889`

    The IMAP APPENDLIMIT Extension

:rfc:`7932`

    Brotli Compressed Data Format

:rfc:`7953`

    Calendar Availability

:rfc:`7986`

    New Properties for iCalendar

    .. NOTE::

       Support here means, that when the iCalendar stream is retrieved with HTTP GET,
       Cyrus IMAP inserts the color, description and name from the WebDAV properties.
       IMAGE, SOURCE, multi-lingual calendar DESCRIPTIONs, URL, LAST-MODIFIED, CATEGORIES,
       and REFRESH-INTERVAL are not exported on iCalendar streams retrieved with GET.

       Individual iCalendar objects (VEVENT, VTODO, VJOURNAL) can be uploaded and
       downloaded with the New Properties for iCalendar.

:rfc:`8144`

    Use of the Prefer Header Field in Web Distributed Authoring and
    Versioning (WebDAV)

:rfc:`8246`

    HTTP Immutable Responses

:rfc:`8288`

    Web Linking

:rfc:`8297`

    An HTTP Status Code for Indicating Hints

:rfc:`8437`

    IMAP UNAUTHENTICATE Extension for Connection Reuse

:rfc:`8438`

    IMAP Extension for STATUS=SIZE

:rfc:`8440`

    IMAP4 Extension for Returning MYRIGHTS Information in Extended LIST

:rfc:`8441`

    Bootstrapping WebSockets with HTTP/2

:rfc:`8474`

    IMAP Extension for Object Identifiers

:rfc:`8514`

    Internet Message Access Protocol (IMAP) - SAVEDATE Extension

:rfc:`8579`

    Sieve Email Filtering: Delivering to Special-Use Mailboxes

:rfc:`8580`

    Sieve Extension: File Carbon Copy (FCC)

:rfc:`8607`

    Calendaring Extensions to WebDAV (CalDAV): Managed Attachments

:rfc:`8620`

    The JSON Meta Application Protocol (JMAP)

:rfc:`8621`

    The JSON Meta Application Protocol (JMAP) for Mail

:rfc:`8878`

    Zstandard Compression and the application/zstd Media Type

:rfc:`8887`

    A JSON Meta Application Protocol (JMAP) Subprotocol for WebSocket

:rfc:`8970`

    IMAP4 Extension: Message Preview Generation

IETF RFC Drafts
===============

draft-ietf-extra-sieve-mailboxid

    Sieve Email Filtering: delivery by mailboxid

draft-ietf-extra-sieve-snooze

    Sieve Email Filtering: Snooze Extension

draft-ietf-jmap-calendars

    JMAP for Calendars

draft-ietf-jmap-sieve

    JMAP for Sieve Scripts

draft-murchison-lmtp-ignorequota

    LMTP Service Extension for Ignoring Recipient Quotas

[MS-NTHT]   NTLM Over HTTP Protocol Specification

draft-ietf-sieve-regex

    Sieve Email Filtering -- Regular Expression Extension

draft-martin-sieve-notify

    Sieve -- An extension for providing instant notifications

draft-york-vpoll

    VPOLL: Consensus Scheduling Component for iCalendar

draft-desruisseaux-ischedule

    Internet Calendar Scheduling Protocol (iSchedule)

draft-thomson-hybi-http-timeout

    Hypertext Transfer Protocol (HTTP) Keep-Alive Header

..

    caldav-ctag     Calendar Collection Entity Tag (CTag) in CalDAV
    Brief Header    Microsoft 'Brief' header extension

RFC Wishlist
============

:rfc:`2221`

    IMAP4 Login Referrals

:rfc:`2295`

    Transparent Content Negotiation in HTTP

:rfc:`2369`

    The Use of URLs as Meta-Syntax for Core Mail List Commands
    and their Transport through Message Header Fields

:rfc:`3229`

    Delta encoding in HTTP

:rfc:`5182`

    IMAP Extension for Referencing the Last SEARCH Result

:rfc:`5255`

    Internet Message Access Protocol Internationalization

:rfc:`5259`

    Internet Message Access Protocol - CONVERT Extension

:rfc:`5437`

    Sieve Notification Mechanism: Extensible Messaging and Presence
    Protocol (XMPP)

:rfc:`5465`

    The IMAP NOTIFY Extension

:rfc:`5466`

    IMAP4 Extension for Named Searches (Filters)

:rfc:`5550`

    The Internet Email to Support Diverse Service Environments (Lemonade) Profile

:rfc:`5842`

    Binding Extensions to Web Distributed Authoring and Versioning (WebDAV)

:rfc:`6468`

    Sieve Notification Mechanism: SIP MESSAGE

:rfc:`6785`

    Support for Internet Message Access Protocol (IMAP) Events in Sieve

:rfc:`6855`

    IMAP Support for UTF-8

:rfc:`7162`

    IMAP Extensions: Quick Flag Changes Resynchronization (CONDSTORE)
    and Quick Mailbox Resynchronization (QRESYNC)

:rfc:`7377`

    IMAP4 Multimailbox SEARCH Extension

:rfc:`7888`

    IMAP4 Non-synchronizing Literals

:rfc:`8470`

    Using Early Data in HTTP

:rfc:`8508`

    IMAP REPLACE Extension
