7Network Working Group                                       G. Vaudreuil
 
8Request for Comments: 3462                           Lucent Technologies
 
9Obsoletes: 1892                                             January 2003
 
10Category: Standards Track
 
13                   The Multipart/Report Content Type
 
15                  Mail System Administrative Messages
 
19   This document specifies an Internet standards track protocol for the
 
20   Internet community, and requests discussion and suggestions for
 
21   improvements.  Please refer to the current edition of the "Internet
 
22   Official Protocol Standards" (STD 1) for the standardization state
 
23   and status of this protocol.  Distribution of this memo is unlimited.
 
27   Copyright (C) The Internet Society (2003).  All Rights Reserved.
 
31   The Multipart/Report Multipurpose Internet Mail Extensions (MIME)
 
32   content-type is a general "family" or "container" type for electronic
 
33   mail reports of any kind.  Although this memo defines only the use of
 
34   the Multipart/Report content-type with respect to delivery status
 
35   reports, mail processing programs will benefit if a single content-
 
36   type is used to for all kinds of reports.
 
38   This document is part of a four document set describing the delivery
 
39   status report service.  This collection includes the Simple Mail
 
40   Transfer Protocol (SMTP) extensions to request delivery status
 
41   reports, a MIME content for the reporting of delivery reports, an
 
42   enumeration of extended status codes, and a multipart container for
 
43   the delivery report, the original message, and a human-friendly
 
44   summary of the failure.
 
58Vaudreuil                   Standards Track                     [Page 1]
 
60RFC 3462                    Multipart/Report                January 2003
 
65   Document Conventions................................................2
 
66   1. The Multipart/Report Content Type................................2
 
67   2. The Text/RFC822-Headers..........................................4
 
68   3. Security Considerations..........................................4
 
69   4. Normative References.............................................5
 
70   Appendix A - Changes from RFC 1893..................................6
 
71   Author's Address....................................................6
 
72   Full Copyright Statement............................................7
 
76   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
 
77   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
 
78   document are to be interpreted as described in BCP 14, RFC 2119
 
811. The Multipart/Report Content Type
 
83   The Multipart/Report MIME content-type is a general "family" or
 
84   "container" type for electronic mail reports of any kind. Although
 
85   this memo defines only the use of the Multipart/Report content-type
 
86   with respect to delivery status reports, mail processing programs
 
87   will benefit if a single content-type is used to for all kinds of
 
90   The Multipart/Report content-type is defined as follows:
 
92      MIME type name: multipart
 
93      MIME subtype name: report
 
94      Required parameters: boundary, report-type
 
95      Optional parameters: none
 
96      Encoding considerations: 7bit should always be adequate
 
97      Security considerations: see section 3 of this memo
 
99   The syntax of Multipart/Report is identical to the Multipart/Mixed
 
100   content type defined in [MIME].  When used to send a report, the
 
101   Multipart/Report content-type must be the top-level MIME content type
 
102   for any report message.  The report-type parameter identifies the
 
103   type of report.  The parameter is the MIME content sub-type of the
 
104   second body part of the Multipart/Report.
 
106   User agents and gateways must be able to automatically determine that
 
107   a message is a mail system report and should be processed as such.
 
108   Placing the Multipart/Report as the outermost content provides a
 
109   mechanism whereby an auto-processor may detect through parsing the
 
110   RFC 822 headers that the message is a report.
 
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116RFC 3462                    Multipart/Report                January 2003
 
120   parts, in the following order:
 
122   1) [Required] The first body part contains human readable message.
 
123   The purpose of this message is to provide an easily understood
 
124   description of the condition(s) that caused the report to be
 
125   generated, for a human reader who may not have a user agent capable
 
126   of interpreting the second section of the Multipart/Report.
 
128   The text in the first section may be in any MIME standards-track
 
129   content-type, charset, or language.  Where a description of the error
 
130   is desired in several languages or several media, a
 
131   Multipart/Alternative construct may be used.
 
133   This body part may also be used to send detailed information that
 
134   cannot be easily formatted into a Message/Report body part.
 
136   (2) [Required] A machine parsable body part containing an account of
 
137   the reported message handling event. The purpose of this body part is
 
138   to provide a machine-readable description of the condition(s) that
 
139   caused the report to be generated, along with details not present in
 
140   the first body part that may be useful to human experts.  An initial
 
141   body part, Message/delivery-status is defined in [DSN].
 
143   (3) [Optional] A body part containing the returned message or a
 
144   portion thereof.  This information may be useful to aid human experts
 
145   in diagnosing problems.  (Although it may also be useful to allow the
 
146   sender to identify the message which the report was issued, it is
 
147   hoped that the envelope-id and original-recipient-address returned in
 
148   the Message/Report body part will replace the traditional use of the
 
149   returned content for this purpose.)
 
151   Return of content may be wasteful of network bandwidth and a variety
 
152   of implementation strategies can be used.  Generally the sender
 
153   should choose the appropriate strategy and inform the recipient of
 
154   the required level of returned content required.  In the absence of
 
155   an explicit request for level of return of content such as that
 
156   provided in [DRPT], the agent that generated the delivery service
 
157   report should return the full message content.
 
159   When 8-bit or binary data not encoded in a 7 bit form is to be
 
160   returned, and the return path is not guaranteed to be 8-bit or binary
 
161   capable, two options are available.  The original message MAY be re-
 
162   encoded into a legal 7-bit MIME message or the Text/RFC822-Headers
 
163   content-type MAY be used to return only the original message headers.
 
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172RFC 3462                    Multipart/Report                January 2003
 
177   The Text/RFC822-Headers MIME content-type provides a mechanism to
 
178   label and return only the RFC 822 headers of a failed message.  These
 
179   headers are not the complete message and should not be returned as a
 
180   Message/RFC822. The returned headers are useful for identifying the
 
181   failed message and for diagnostics based on the received lines.
 
183   The Text/RFC822-Headers content-type is defined as follows:
 
186      MIME subtype name: RFC822-Headers
 
187      Required parameters: None
 
188      Optional parameters: None
 
189      Encoding considerations: 7 bit is sufficient for normal RFC822
 
190                headers, however, if the headers are broken and require
 
191                encoding to make them legal 7 bit content, they may be
 
192                encoded in quoted-printable.
 
193      Security considerations: See section 3 of this memo.
 
195   The Text/RFC822-Headers body part should contain all the RFC822
 
196   header lines from the message which caused the report.  The RFC822
 
197   headers include all lines prior to the blank line in the message.
 
198   They include the MIME-Version and MIME Content-Headers.
 
2003. Security Considerations
 
202   Automated use of report types without authentication presents several
 
203   security issues.  Forging negative reports presents the opportunity
 
204   for denial-of-service attacks when the reports are used for automated
 
205   maintenance of directories or mailing lists.  Forging positive
 
206   reports may cause the sender to incorrectly believe a message was
 
207   delivered when it was not.
 
209   A signature covering the entire multipart/report structure could be
 
210   used to prevent such forgeries; such a signature scheme is, however,
 
211   beyond the scope of this document.
 
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228RFC 3462                    Multipart/Report                January 2003
 
2314. Normative References
 
233   [SMTP]     Postel, J., "Simple Mail Transfer Protocol", STD 10, RFC
 
236   [DSN]      Moore, K., and G. Vaudreuil, "An Extensible Message Format
 
237              for Delivery Status Notifications", RFC 3464, January
 
240   [RFC822]   Crocker, D., "Standard for the format of ARPA Internet
 
241              Text Messages", STD 11, RFC 822, August 1982.
 
243   [MIME]     Borenstein, N. and N. Freed, "Multipurpose Internet Mail
 
244              Extensions (MIME) Part Two: Media Types", RFC 2046,
 
247   [DRPT]     Moore, K., "SMTP Service Extension for Delivery Status
 
248              Notifications", RFC 3461, January 2003.
 
250   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
 
251              Requirement Levels", BCP 14, RFC 2119, March 1997.
 
282Vaudreuil                   Standards Track                     [Page 5]
 
284RFC 3462                    Multipart/Report                January 2003
 
287Appendix A - Changes from RFC 1892
 
289   Changed Authors contact information
 
291   Updated required standards boilerplate
 
293   Edited the text to make it spell-checker and grammar checker
 
303   Phone: +1 214 823 9325
 
304   EMail: GregV@ieee.org
 
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340RFC 3462                    Multipart/Report                January 2003
 
343Full Copyright Statement
 
345   Copyright (C) The Internet Society (2003).  All Rights Reserved.
 
347   This document and translations of it may be copied and furnished to
 
348   others, and derivative works that comment on or otherwise explain it
 
349   or assist in its implementation may be prepared, copied, published
 
350   and distributed, in whole or in part, without restriction of any
 
351   kind, provided that the above copyright notice and this paragraph are
 
352   included on all such copies and derivative works.  However, this
 
353   document itself may not be modified in any way, such as by removing
 
354   the copyright notice or references to the Internet Society or other
 
355   Internet organizations, except as needed for the purpose of
 
356   developing Internet standards in which case the procedures for
 
357   copyrights defined in the Internet Standards process must be
 
358   followed, or as required to translate it into languages other than
 
361   The limited permissions granted above are perpetual and will not be
 
362   revoked by the Internet Society or its successors or assigns.
 
364   This document and the information contained herein is provided on an
 
365   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
 
366   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 
367   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
 
368   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
 
369   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
 
373   Funding for the RFC Editor function is currently provided by the
 
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