IMAP URL Scheme
RFC 5092

Network Working Group                                   A. Melnikov, Ed.
Request for Comments: 5092                                    Isode Ltd.
Obsoletes: 2192                                                C. Newman
Updates: 4467                                           Sun Microsystems
Category: Standards Track                                  November 2007

                            IMAP URL Scheme

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Abstract

   IMAP (RFC 3501) is a rich protocol for accessing remote message
   stores.  It provides an ideal mechanism for accessing public mailing
   list archives as well as private and shared message stores.  This
   document defines a URL scheme for referencing objects on an IMAP
   server.

   This document obsoletes RFC 2192.  It also updates RFC 4467.

Melnikov & Newman           Standards Track                     [Page 1]
RFC 5092                    IMAP URL Scheme                November 2007

Table of Contents

   1. Introduction ....................................................2
   2. Conventions Used in This Document ...............................3
   3. IMAP userinfo Component (iuserinfo) .............................4
      3.1. IMAP Mailbox Naming Scope ..................................4
      3.2. IMAP User Name and Authentication Mechanism ................4
      3.3. Limitations of enc-user ....................................6
   4. IMAP Server .....................................................7
   5. Lists of Messages ...............................................7
   6. A Specific Message or Message Part ..............................8
      6.1. URLAUTH Authorized URL .....................................9
           6.1.1. Concepts ............................................9
                  6.1.1.1. URLAUTH ....................................9
                  6.1.1.2. Mailbox Access Key .........................9
                  6.1.1.3. Authorized Access Identifier ...............9
                  6.1.1.4. Authorization Mechanism ...................10
                  6.1.1.5. Authorization Token .......................10
           6.1.2. URLAUTH Extensions to IMAP URL .....................10
   7. Relative IMAP URLs .............................................11
      7.1. absolute-path References ..................................12
      7.2. relative-path References ..................................12
   8. Internationalization Considerations ............................13
   9. Examples .......................................................13
      9.1. Examples of Relative URLs .................................16
   10. Security Considerations .......................................16
      10.1. Security Considerations Specific to URLAUTH Authorized
            URL ......................................................17
   11. ABNF for IMAP URL Scheme ......................................17
   12. IANA Considerations ...........................................21
      12.1. IANA Registration of imap: URI Scheme ....................21
   13. References ....................................................22
      13.1. Normative References .....................................22
      13.2. Informative References ...................................23
   Appendix A. Sample Code............................................24
   Appendix B. List of Changes since RFC 2192.........................30
   Appendix C. List of Changes since RFC 4467.........................31
   Appendix D. Acknowledgments........................................31

1.  Introduction

   The IMAP URL scheme is used to designate IMAP servers, mailboxes,
   messages, MIME bodies [MIME], and search programs on Internet hosts
   accessible using the IMAP protocol over TCP.

   The IMAP URL follows the common Internet scheme syntax as defined in
   [URI-GEN].  If :<port> is omitted, the port defaults to 143 (as
   defined in Section 2.1 of [IMAP4]).

Melnikov & Newman           Standards Track                     [Page 2]
RFC 5092                    IMAP URL Scheme                November 2007

   An absolute IMAP URL takes one of the following forms:

      imap://<iserver>[/]

      imap://<iserver>/<enc-mailbox>[<uidvalidity>][?<enc-search>]

      imap://<iserver>/<enc-mailbox>[<uidvalidity>]<iuid>
       [<isection>][<ipartial>][<iurlauth>]