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

   New in version 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

   New in version 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 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

   New in version 2.5.0.

**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 7804**

   Salted Challenge Response HTTP Authentication Mechanism

**RFC 7808**

   Time Zone Data Distribution Service

**RFC 7809**

   CalDAV: Time Zones by Reference

**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 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 8478**

   Zstandard Compression and the application/zstd Media Type

**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


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

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-gondwana-sieve-mailboxid

   Sieve Email Filtering: delivery by mailboxid

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 6901**

   JavaScript Object Notation (JSON) Pointer

**RFC 7162**

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

**RFC 7377**

   IMAP4 Multimailbox SEARCH Extension

**RFC 7725**

   An HTTP Status Code to Report Legal Obstacles

**RFC 7888**

   IMAP4 Non-synchronizing Literals

**RFC 7889**

   The IMAP APPENDLIMIT Extension

**RFC 8288**

   Web Linking

**RFC 8470**

   Using Early Data in HTTP

**RFC 8474**

   IMAP Extension for Object Identifiers

   Note: This is implemented as draft-ietf-extra-imap-objectid.

**RFC 8508**

   IMAP REPLACE Extension

**RFC 8514**

   Internet Message Access Protocol (IMAP) - SAVEDATE Extension

   Note: This is implemented as draft-ietf-extra-imap-savedate.

**RFC 8621**

   The JSON Meta Application Protocol (JMAP) for Mail
