Network Working Group                                        A. Melnikov
Internet-Draft                                                 Isode Ltd
Updates: 3501 (if approved)                              SB. Jayantheesh
Intended status: Standards Track             Samsung Electronics America
Expires: March 16, 2018                               September 12, 2017


               64bit body part and message sizes in IMAP4
                     draft-ietf-extra-imap-64bit-00

Abstract

   This document defines an IMAPv4rev1 extension that extends the
   existing IMAPv4rev1 32 Bit message and body part sizes to 63 bit.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
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   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on March 16, 2018.

Copyright Notice

   Copyright (c) 2017 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
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   described in the Simplified BSD License.





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   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Notation . . . . . . . . . . . . . . . . . . . .   2
   3.  64bit Extension . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  IMAP Protocol Changes . . . . . . . . . . . . . . . . . . . .   3
   5.  Examples  . . . . . . . . . . . . . . . . . . . . . . . . . .   3
   6.  Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . .   3
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   4
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
   9.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   5
   10. Normative References  . . . . . . . . . . . . . . . . . . . .   5
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   5

1.  Introduction

   IMAP [RFC3501] only allows body parts or message sizes which are
   32bit.  This document introduces an IMAP extension that allows for
   message and body part sizes to be 63bit.

   The client wishing to use this extension MUST issue ENABLE 64BIT
   command.  Refer [RFC5161] for the usage of ENABLE command.

2.  Requirements Notation

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

   In examples, "C:" and "S:" indicate lines sent by the client and
   server respectively.  If a single "C:" or "S:" label applies to
   multiple lines, then the line breaks between those lines are for
   editorial clarity only and are not part of the actual protocol
   exchange.





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3.  64bit Extension

   An IMAP server that supports the 64bit extension advertises this by
   including the name 64BIT in its CAPABILITY list in the authenticated
   state.  The server may also advertise this extension before the user
   has logged in.  If this capability is omitted, no information is
   conveyed about the server's status of supporting this extension.
   IMAP server should respond with BAD response for the 64bit message
   size messages sent by the IMAP client unless it issues "ENABLE 64BIT"
   in the current connection.

4.  IMAP Protocol Changes

   TBD.

5.  Examples

     C: t1 CAPABILITY
     S: * CAPABILITY IMAP4rev1 ID 64BIT
     S: t1 OK foo
     C: t2 ENABLE 64BIT
     S: * ENABLED 64BIT
     S: t2 OK foo

6.  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
   [RFC3501].




















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  body-extension  =/ number64
             ; Alexey: I am not sure if this change is absolutely needed!

  body-fld-lines  = number64

  body-fld-octets = number64

  fetch-att       =/ "BODY" section ["<" number "." nz-number ">"] /
                     "BODY.PEEK" section ["<" number "." nz-number ">"]

  literal         = "{" number64 ["+"] "}" CRLF *CHAR8
                    ; number64 represents the number of CHAR8s.
                    ; NOTE: "+" can only present when LITERAL+/LITERAL-
                    ; is also advertised

  msg-att-static  =/ "RFC822.SIZE" SP number

  search-key      =/ "LARGER" SP number / "SMALLER" SP number

  number64    = 1*DIGIT
                ; Unsigned 63-bit integer
                ; (0 <= n <= 9,223,372,036,854,775,807)

  nz-number64 = digit-nz *DIGIT
                ; Unsigned 63-bit integer
                ; (0 < n <= 9,223,372,036,854,775,807)


  CHAR8   = <defined in RFC 3501>


  literal8 = <defined in RFC 4466>
             ; Alexey: this needs updating as well

7.  Security Considerations

   TBD.

   This document doesn't raise any other security concerns not already
   raised by [RFC3501].

8.  IANA Considerations

   IMAP4 capabilities are registered by publishing a standards track or
   IESG approved experimental RFC.  The registry is currently located
   at:

      http://www.iana.org/assignments/imap-capabilities



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   This document requests that IANA adds to the above registry to
   include the entry for 64BIT capability pointing to this document.

9.  Acknowledgments

   TBD

10.  Normative References

   [ABNF]     Crocker, D. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234, January 2008.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC3501]  Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
              4rev1", RFC 3501, DOI 10.17487/RFC3501, March 2003,
              <https://www.rfc-editor.org/info/rfc3501>.

   [RFC3516]  Nerenberg, L., "IMAP4 Binary Content Extension", RFC 3516,
              DOI 10.17487/RFC3516, April 2003,
              <https://www.rfc-editor.org/info/rfc3516>.

   [RFC4466]  Melnikov, A. and C. Daboo, "Collected Extensions to IMAP4
              ABNF", RFC 4466, DOI 10.17487/RFC4466, April 2006,
              <https://www.rfc-editor.org/info/rfc4466>.

   [RFC5161]  Gulbrandsen, A., Ed. and A. Melnikov, Ed., "The IMAP
              ENABLE Extension", RFC 5161, DOI 10.17487/RFC5161, March
              2008, <https://www.rfc-editor.org/info/rfc5161>.

Authors' Addresses

   Alexey Melnikov
   Isode Ltd
   14 Castle
   Mews
   Hampton, Middlesex  TW12 2NP
   UK

   Email: Alexey.Melnikov@isode.com








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   Jayantheesh S B
   Samsung Electronics America
   685 US Highway 202/206
   Bridgewater, New Jersey  08807
   USA

   Email: jayantheesh.sb@gmail.com












































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