Network Working Group                                       G. Vaudreuil
Request for Comments: 3462                           Lucent Technologies
Obsoletes: 1892                                             January 2003
Category: Standards Track


                  The Multipart/Report Content Type
                        for the Reporting of
                 Mail System Administrative Messages

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.

Copyright Notice

  Copyright (C) The Internet Society (2003).  All Rights Reserved.

Abstract

  The Multipart/Report Multipurpose Internet Mail Extensions (MIME)
  content-type is a general "family" or "container" type for electronic
  mail reports of any kind.  Although this memo defines only the use of
  the Multipart/Report content-type with respect to delivery status
  reports, mail processing programs will benefit if a single content-
  type is used to for all kinds of reports.

  This document is part of a four document set describing the delivery
  status report service.  This collection includes the Simple Mail
  Transfer Protocol (SMTP) extensions to request delivery status
  reports, a MIME content for the reporting of delivery reports, an
  enumeration of extended status codes, and a multipart container for
  the delivery report, the original message, and a human-friendly
  summary of the failure.













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Table of Contents

  Document Conventions................................................2
  1. The Multipart/Report Content Type................................2
  2. The Text/RFC822-Headers..........................................4
  3. Security Considerations..........................................4
  4. Normative References.............................................5
  Appendix A - Changes from RFC 1893..................................6
  Author's Address....................................................6
  Full Copyright Statement............................................7

Document Conventions

  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 BCP 14, RFC 2119
  [RFC2119].

1. The Multipart/Report Content Type

  The Multipart/Report MIME content-type is a general "family" or
  "container" type for electronic mail reports of any kind. Although
  this memo defines only the use of the Multipart/Report content-type
  with respect to delivery status reports, mail processing programs
  will benefit if a single content-type is used to for all kinds of
  reports.

  The Multipart/Report content-type is defined as follows:

     MIME type name: multipart
     MIME subtype name: report
     Required parameters: boundary, report-type
     Optional parameters: none
     Encoding considerations: 7bit should always be adequate
     Security considerations: see section 3 of this memo

  The syntax of Multipart/Report is identical to the Multipart/Mixed
  content type defined in [MIME].  When used to send a report, the
  Multipart/Report content-type must be the top-level MIME content type
  for any report message.  The report-type parameter identifies the
  type of report.  The parameter is the MIME content sub-type of the
  second body part of the Multipart/Report.

  User agents and gateways must be able to automatically determine that
  a message is a mail system report and should be processed as such.
  Placing the Multipart/Report as the outermost content provides a
  mechanism whereby an auto-processor may detect through parsing the
  RFC 822 headers that the message is a report.



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  The Multipart/Report content-type contains either two or three sub-
  parts, in the following order:

  1) [Required] The first body part contains human readable message.
  The purpose of this message is to provide an easily understood
  description of the condition(s) that caused the report to be
  generated, for a human reader who may not have a user agent capable
  of interpreting the second section of the Multipart/Report.

  The text in the first section may be in any MIME standards-track
  content-type, charset, or language.  Where a description of the error
  is desired in several languages or several media, a
  Multipart/Alternative construct may be used.

  This body part may also be used to send detailed information that
  cannot be easily formatted into a Message/Report body part.

  (2) [Required] A machine parsable body part containing an account of
  the reported message handling event. The purpose of this body part is
  to provide a machine-readable description of the condition(s) that
  caused the report to be generated, along with details not present in
  the first body part that may be useful to human experts.  An initial
  body part, Message/delivery-status is defined in [DSN].

  (3) [Optional] A body part containing the returned message or a
  portion thereof.  This information may be useful to aid human experts
  in diagnosing problems.  (Although it may also be useful to allow the
  sender to identify the message which the report was issued, it is
  hoped that the envelope-id and original-recipient-address returned in
  the Message/Report body part will replace the traditional use of the
  returned content for this purpose.)

  Return of content may be wasteful of network bandwidth and a variety
  of implementation strategies can be used.  Generally the sender
  should choose the appropriate strategy and inform the recipient of
  the required level of returned content required.  In the absence of
  an explicit request for level of return of content such as that
  provided in [DRPT], the agent that generated the delivery service
  report should return the full message content.

  When 8-bit or binary data not encoded in a 7 bit form is to be
  returned, and the return path is not guaranteed to be 8-bit or binary
  capable, two options are available.  The original message MAY be re-
  encoded into a legal 7-bit MIME message or the Text/RFC822-Headers
  content-type MAY be used to return only the original message headers.






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RFC 3462                    Multipart/Report                January 2003


2. The Text/RFC822-Headers content-type

  The Text/RFC822-Headers MIME content-type provides a mechanism to
  label and return only the RFC 822 headers of a failed message.  These
  headers are not the complete message and should not be returned as a
  Message/RFC822. The returned headers are useful for identifying the
  failed message and for diagnostics based on the received lines.

  The Text/RFC822-Headers content-type is defined as follows:

     MIME type name: Text
     MIME subtype name: RFC822-Headers
     Required parameters: None
     Optional parameters: None
     Encoding considerations: 7 bit is sufficient for normal RFC822
               headers, however, if the headers are broken and require
               encoding to make them legal 7 bit content, they may be
               encoded in quoted-printable.
     Security considerations: See section 3 of this memo.

  The Text/RFC822-Headers body part should contain all the RFC822
  header lines from the message which caused the report.  The RFC822
  headers include all lines prior to the blank line in the message.
  They include the MIME-Version and MIME Content-Headers.

3. Security Considerations

  Automated use of report types without authentication presents several
  security issues.  Forging negative reports presents the opportunity
  for denial-of-service attacks when the reports are used for automated
  maintenance of directories or mailing lists.  Forging positive
  reports may cause the sender to incorrectly believe a message was
  delivered when it was not.

  A signature covering the entire multipart/report structure could be
  used to prevent such forgeries; such a signature scheme is, however,
  beyond the scope of this document.














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RFC 3462                    Multipart/Report                January 2003


4. Normative References

  [SMTP]     Postel, J., "Simple Mail Transfer Protocol", STD 10, RFC
             821, August 1982.

  [DSN]      Moore, K., and G. Vaudreuil, "An Extensible Message Format
             for Delivery Status Notifications", RFC 3464, January
             2003.

  [RFC822]   Crocker, D., "Standard for the format of ARPA Internet
             Text Messages", STD 11, RFC 822, August 1982.

  [MIME]     Borenstein, N. and N. Freed, "Multipurpose Internet Mail
             Extensions (MIME) Part Two: Media Types", RFC 2046,
             November 1996.

  [DRPT]     Moore, K., "SMTP Service Extension for Delivery Status
             Notifications", RFC 3461, January 2003.

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.






























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RFC 3462                    Multipart/Report                January 2003


Appendix A - Changes from RFC 1892

  Changed Authors contact information

  Updated required standards boilerplate

  Edited the text to make it spell-checker and grammar checker
  compliant

Author's Address

  Gregory M. Vaudreuil
  Lucent Technologies
  7291 Williamson Rd
  Dallas Tx, 75214

  Phone: +1 214 823 9325
  EMail: [email protected]

































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RFC 3462                    Multipart/Report                January 2003


Full Copyright Statement

  Copyright (C) The Internet Society (2003).  All Rights Reserved.

  This document and translations of it may be copied and furnished to
  others, and derivative works that comment on or otherwise explain it
  or assist in its implementation may be prepared, copied, published
  and distributed, in whole or in part, without restriction of any
  kind, provided that the above copyright notice and this paragraph are
  included on all such copies and derivative works.  However, this
  document itself may not be modified in any way, such as by removing
  the copyright notice or references to the Internet Society or other
  Internet organizations, except as needed for the purpose of
  developing Internet standards in which case the procedures for
  copyrights defined in the Internet Standards process must be
  followed, or as required to translate it into languages other than
  English.

  The limited permissions granted above are perpetual and will not be
  revoked by the Internet Society or its successors or assigns.

  This document and the information contained herein is provided on an
  "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
  TASK FORCE DISCLAIMS 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.

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.



















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