idnits 2.17.1 draft-ietf-msgtrk-trkstat-02.txt: ** The Abstract section seems to be numbered Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- ** Looks like you're using RFC 2026 boilerplate. This must be updated to follow RFC 3978/3979, as updated by RFC 4748. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- ** Missing expiration date. The document expiration date should appear on the first and last page. ** The document seems to lack a 1id_guidelines paragraph about Internet-Drafts being working documents. ** The document seems to lack a 1id_guidelines paragraph about the list of current Internet-Drafts -- however, there's a paragraph with a matching beginning. Boilerplate error? ** The document seems to lack a 1id_guidelines paragraph about the list of Shadow Directories -- however, there's a paragraph with a matching beginning. Boilerplate error? == No 'Intended status' indicated for this document; assuming Proposed Standard == The page length should not exceed 58 lines per page, but there was 9 longer pages, the longest (page 2) being 62 lines Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- ** The document seems to lack an Introduction section. ** The document seems to lack a Security Considerations section. (A line matching the expected section header was found, but with an unexpected indentation: ' Security considerations: discussed in section 4 of this memo.' ) ** The document seems to lack an IANA Considerations section. (See Section 2.2 of https://www.ietf.org/id-info/checklist for how to handle the case when there are no actions for IANA.) ** There are 117 instances of weird spacing in the document. Is it really formatted ragged-right, rather than justified? ** There is 1 instance of too long lines in the document, the longest one being 1 character in excess of 72. ** The abstract seems to contain references ([RFC-ESMTP], [RFC-DSN-STAT], [RFC-MIME], [DRAFT-MTRK-SMTPEXT], [RFC-MDN], [DRAFT-MTRK-MTQP], [RFC-DSN-SMTP]), which it shouldn't. Please replace those with straight textual mentions of the documents in question. == The 'Updates: ' line in the draft header should list only the _numbers_ of the RFCs which will be updated by this document (if approved); it should not include the word 'RFC' in the list. Miscellaneous warnings: ---------------------------------------------------------------------------- == Line 13 has weird spacing: '... This docum...' == Line 14 has weird spacing: '...-Drafts are...' == Line 15 has weird spacing: '...working docum...' == Line 16 has weird spacing: '...ups may also ...' == Line 20 has weird spacing: '...eted by other...' == (112 more instances...) -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (July 6, 2001) is 8329 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) -- Missing reference section? 'RFC-DSN-SMTP' on line 384 looks like a reference -- Missing reference section? 'RFC-MDN' on line 413 looks like a reference -- Missing reference section? 'RFC-MIME' on line 417 looks like a reference -- Missing reference section? 'RFC-DSN-STAT' on line 388 looks like a reference -- Missing reference section? 'DRAFT-MTRK-MTQP' on line 367 looks like a reference -- Missing reference section? 'RFC-ESMTP' on line 396 looks like a reference -- Missing reference section? 'DRAFT-MTRK-SMTPEXT' on line 371 looks like a reference -- Missing reference section? 'DRAFT-MTRK-MODEL' on line 363 looks like a reference -- Missing reference section? 'RFC-ABNF' on line 375 looks like a reference -- Missing reference section? 'RFC-MSGFMT' on line 422 looks like a reference -- Missing reference section? 'RFC-HOSTREQ' on line 401 looks like a reference -- Missing reference section? 'RFC-KEYWORDS' on line 405 looks like a reference -- Missing reference section? 'RFC-RELATED' on line 426 looks like a reference -- Missing reference section? 'RFC-EMSSC' on line 392 looks like a reference -- Missing reference section? 'RFC-LMTP' on line 409 looks like a reference -- Missing reference section? 'RFC-DSN-REPT' on line 379 looks like a reference Summary: 12 errors (**), 0 flaws (~~), 9 warnings (==), 18 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Internet Draft E. Allman 3 draft-ietf-msgtrk-trkstat-02.txt Sendmail, Inc. 4 Valid for six months July 6, 2001 5 Updates: RFC 1893 7 The Message/Tracking-Status MIME Extension 9 11 Status of This Memo 13 This document is an Internet-Draft and is in full conformance 14 with all provisions of Section 10 of RFC2026. Internet-Drafts are 15 working documents of the Internet Engineering Task Force (IETF), its 16 areas, and its working groups. Note that other groups may also dis- 17 tribute working documents as Internet-Drafts. 19 Internet-Drafts are draft documents valid for a maximum of six 20 months and may be updated, replaced, or obsoleted by other documents 21 at any time. It is inappropriate to use Internet-Drafts as reference 22 material or to cite them other than as "work in progress." 24 The list of current Internet-Drafts can be accessed at: 26 http://www.ietf.org/ietf/1id-abstracts.txt 28 The list of Internet-Draft Shadow Directories can be accessed at: 30 http://www.ietf.org/shadow.html 32 This document is a submission by the MSGTRK Working Group of the 33 Internet Engineering Task Force (IETF). Comments should be submitted 34 to the ietf-msgtrk@imc.org mailing list. An archive of the mailing 35 list may be found at 37 http://www.imc.org/ietf-msgtrk/index.html 39 Distribution of this memo is unlimited. 41 1. Abstract 43 Message Tracking is expected to be used to determine the sta- 44 tus of undelivered e-mail upon request. Tracking is used in con- 45 junction with Delivery Status Notifications [RFC-DSN-SMTP] and Mes- 46 sage Disposition Notifications [RFC-MDN]; generally, a message 47 tracking request will be issued only when a DSN or MDN has not been 48 received within a reasonable timeout period. 50 This memo defines a MIME [RFC-MIME] content-type for message 51 tracking status in the same spirit as RFC 1894, ``An Extensible 52 Message Format for Delivery Status Notifications'' [RFC-DSN-STAT]. 54 It is to be issued upon a request as described in ``Message Track- 55 ing Query Protocol'' [DRAFT-MTRK-MTQP]. This memo defines only the 56 format of the status information. An extension to SMTP [RFC-ESMTP] 57 to label messages for further tracking and request tracking status 58 is defined in a separate memo [DRAFT-MTRK-SMTPEXT]. 60 2. Other Documents and Conformance 62 The model used for Message Tracking is described in [DRAFT- 63 MTRK-MODEL]. 65 Message tracking is intended for use as a "last resort" mecha- 66 nism. Normally, Delivery Status Notifications (DSNs) [RFC-DSN- 67 SMTP] and Message Disposition Notifications (MDNs) [RFC-MDN] would 68 provide the primary delivery status. Only if no response is 69 received from either of these mechanisms would Message Tracking be 70 used. 72 This document is based on [RFC-DSN-STAT]. Sections 1.3 (Ter- 73 minology), 2.1.1 (General conventions for DSN fields), 2.1.2 74 ("*-type" subfields), and 2.1.3 (Lexical tokens imported from RFC 75 822) of [RFC-DSN-STAT] are included into this document by refer- 76 ence. Other sections are further incorporated as described herein. 78 Syntax notation in this document conforms to [RFC-ABNF]. 80 The following lexical tokens, defined in [RFC-MSGFMT], are 81 used in the ABNF grammar for MTSNs: atom, CHAR, comment, CR, CRLF, 82 DIGIT, LF, linear-white-space, SPACE, text. The date-time lexical 83 token is defined in [RFC-HOSTREQ]. 85 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL 86 NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" 87 in this document are to be interpreted as described in RFC 2119 88 [RFC-KEYWORDS]. 90 3. Format of a Message Tracking Status Notification 92 A Message Tracking Status Notification (MTSN) is intended to 93 be returned as the body of a Message Tracking request [DRAFT-MTRK- 94 MTQP]. The actual body MUST be a multipart/related [RFC-RELATED] 95 with type parameter of "message/tracking-status"; each subpart MUST 96 be type "message/tracking-status" as described herein. 98 3.1. The message/tracking-status content-type 100 The message/tracking-status content-type is defined as fol- 101 lows: 103 MIME type name: message 104 MIME subtype name: tracking-status 105 Optional parameters: none 106 Encoding considerations: "7bit" encoding is sufficient and 107 MUST be used to maintain readability 108 when viewed by non-MIME mail readers. 109 Security considerations: discussed in section 4 of this memo. 111 The body of a message/tracking-status is modeled after 112 [RFC-DSN-STAT]. That body consists of one or more "fields" for- 113 matted to according to the ABNF of RFC 822 header "fields" (see 114 [RFC-MSGFMT]). The per-message fields appear first, followed by 115 a blank line. Following the per-message fields are one or more 116 groups of per-recipient fields. Each group of per-recipient 117 fields is preceded by a blank line. Note that there will be a 118 blank line between the final per-recipient field and the MIME 119 boundary, since one CRLF is necessary to terminate the field, 120 and a second is necessary to introduce the MIME boundary. For- 121 mally, the syntax of the message/tracking-status content is as 122 follows: 124 tracking-status-content = 125 per-message-fields 1*( CRLF per-recipient-fields ) 127 The per-message fields are described in section 3.2. The per- 128 recipient fields are described in section 3.3. 130 3.1.1. General conventions for MTSN fields 132 Section 2.1.1 (General conventions for DSN fields) of 133 [RFC-DSN-STAT] is included herein by reference. Notably, the 134 definition of xtext is identical to that of that document. 136 3.1.2. *-type subfields 138 Section 2.1.2 (*-type subfields) of [RFC-DSN-STAT] is 139 included herein by reference. Notably, the definitions of 140 address-type, diagnostic-type, and MTA-name type are identi- 141 cal to that of RFC 1894. 143 3.2. Per-Message MTSN Fields 145 Some fields of an MTSN apply to all of the addresses in a 146 single envelope. These fields may appear at most once in any 147 MTSN. These fields are used to correlate the MTSN with the 148 original message transaction and to provide additional informa- 149 tion which may be useful to gateways. 151 per-message-fields = 152 original-envelope-id-field CRLF 153 reporting-mta-field CRLF 154 arrival-date CRLF 155 *( extension-field CRLF ) 157 3.2.1. The Original-Envelope-Id field 159 The optional Original-Envelope-Id field is defined as in 160 section 2.2.1 of [RFC-DSN-STAT]. This field is REQUIRED. 162 3.2.2. The Reporting-MTA field 164 The Reporting-MTA field is defined as in section 2.2.2 165 of [RFC-DSN-STAT]. This field is REQUIRED. 167 3.2.3. The Arrival-Date field 169 The Arrival-Date field is defined as in section 2.2.5 of 170 [RFC-DSN-STAT]. This field is REQUIRED. 172 3.3. Per-Recipient MTSN fields 174 An MTSN contains information about attempts to deliver a 175 message to one or more recipients. The delivery information for 176 any particular recipient is contained in a group of contiguous 177 per-recipient fields. Each group of per-recipient fields is 178 preceded by a blank line. 180 The syntax for the group of per-recipient fields is as fol- 181 lows: 183 per-recipient-fields = 184 original-recipient-field CRLF 185 final-recipient-field CRLF 186 action-field CRLF 187 status-field CRLF 188 [ remote-mta-field CRLF ] 189 [ last-attempt-date-field CRLF ] 190 [ will-retry-until-field CRLF ] 191 *( extension-field CRLF ) 193 3.3.1. Original-Recipient field 195 The optional Original-Recipient field is defined as in 196 section 2.3.1 of [RFC-DSN-STAT]. This field is REQUIRED. 198 3.3.2. Final-Recipient field 200 The required Final-Recipient field is defined as in sec- 201 tion 2.3.2 of [RFC-DSN-STAT]. This field is REQUIRED. 203 3.3.3. Action field 205 The required Action field indicates the action performed 206 by the Reporting-MTA as a result of its attempt to deliver 207 the message to this recipient address. This field MUST be 208 present for each recipient named in the MTSN. The syntax is 209 as defined in section 2.3.3 of RFC 1894. This field is 210 REQUIRED. 212 Valid actions are: 214 failed The message could not be delivered. If DSNs 215 have been enabled, a "failed" DSN should already 216 have been returned. 218 delayed The message is currently waiting in the MTA 219 queue for future delivery. Essentially, this 220 action means "the message is located, and it is 221 here." 223 delivered The message has been successfully delivered to 224 the final recipient. This includes "delivery" 225 to a mailing list exploder. It does not indi- 226 cate that the message has been read. No further 227 information is available; in particular, the 228 tracking agent SHOULD NOT attempt further "down- 229 stream" tracking requests. 231 expanded The message has been successfully delivered to 232 the recipient address as specified by the 233 sender, and forwarded by the Reporting-MTA 234 beyond that destination to multiple additional 235 recipient addresses. However, these additional 236 addresses are not trackable, and the tracking 237 agent SHOULD NOT attempt further "downstream" 238 tracking requests. 240 relayed The message has been delivered into an environ- 241 ment that does not support message tracking. No 242 further information is available; in particular, 243 the tracking agent SHOULD NOT attempt further 244 "downstream" tracking requests. 246 transferred The message has been transferred to another 247 MTRK-compliant MTA. The tracking agent SHOULD 248 attempt further "downstream" tracking requests. 250 opaque The message may or may not have been seen by 251 this system. No further information is avail- 252 able or forthcoming. 254 There may be some confusion between when to use 255 "expanded" versus "delivered". Whenever possible, "expanded" 256 should be used when the MTA knows that the message will be 257 sent to multiple addresses. However, in some cases the 258 delivery occurs to a program which, unknown to the MTA, 259 causes mailing list expansion; in the extreme case, the 260 delivery may be to a real mailbox that has the side effect of 261 list expansion. If the MTA cannot ensure that this delivery 262 will cause list expansion, it should set the action to 263 "delivered". 265 3.3.4. Status field 267 The Status field is defined as in RFC 1894 section 268 2.3.4. A new code is added to RFC 1893 [RFC-EMSSC], 269 "Enhanced Mail System Status Codes", 271 X.1.9 Message relayed to non-compliant mailer" 273 The mailbox address specified was valid, but the mes- 274 sage has been relayed to a system that does not speak 275 this protocol; no further information can be pro- 276 vided. 277 A 2.1.9 Status field MUST be used exclusively with a 278 "relayed" Action field. This field is REQUIRED. 280 3.3.5. Remote-MTA field 282 The Remote-MTA field is defined as in section Reference 283 2.3.5 of [RFC-DSN-STAT]. This field MUST NOT be included if 284 no delivery attempts have been made or if the Action field 285 has value "opaque". If delivery to some agent other than an 286 MTA (for example, a Local Delivery Agent) then this field MAY 287 be included, giving the name of the host on which that agent 288 was contacted. 290 3.3.6. Last-Attempt-Date field 292 The Last-Attempt-Date field is defined as in section 293 Reference 2.3.7 of [RFC-DSN-STAT]. This field is REQUIRED if 294 any delivery attempt has been made and the Action field does 295 not have value "opaque", in which case it will specify when 296 it last attempted to deliver this message to another MTA or 297 other Delivery Agent. This field MUST NOT be included if no 298 delivery attempts have been made. 300 3.3.7. Will-Retry-Until field 302 The Will-Retry-Until field is defined as in section Ref- 303 erence 2.3.8 of [RFC-DSN-STAT]. If the message is not in the 304 local queue or the Action field has the value ``opaque'' the 305 Will-Retry-Until field MUST NOT be included; otherwise, this 306 field is REQUIRED. 308 3.4. Extension fields 310 Future extension fields may be defined as defined in sec- 311 tion 2.4 of [RFC-DSN-STAT]. 313 3.5. Interaction Between MTAs and LDAs 315 A message that has been delivered to a Local Delivery Agent 316 (LDA) that understands message tracking (in particular, an LDA 317 speaking LMTP [RFC-LMTP] that supports the MTRK extension) 318 SHOULD pass the tracking request to the LDA. In this case, the 319 Action field for the MTA->LDA exchange will look the same as a 320 transfer to a compliant MTA; that is, a "transferred" tracking 321 status will be issued. 323 4. Security Issues 325 4.1. Forgery 327 Malicious servers may attempt to subvert message tracking 328 and return false information. This could result in misdirection 329 or misinterpretation of results. 331 4.2. Confidentiality 333 Another dimension of security is confidentiality. There 334 may be cases in which a message recipient is autoforwarding mes- 335 sages but does not wish to divulge the address to which the mes- 336 sages are autoforwarded. The desire for such confidentiality 337 will probably be heightened as "wireless mailboxes", such as 338 pagers, become more widely used as autoforward addresses. 340 MTA authors are encouraged to provide a mechanism which 341 enables the end user to preserve the confidentiality of a for- 342 warding address. Depending on the degree of confidentiality 343 required, and the nature of the environment to which a message 344 were being forwarded, this might be accomplished by one or more 345 of: 347 (a) respond with a "relayed" tracking status when a message is 348 forwarded to a confidential forwarding address, and dis- 349 abling further message tracking requests. 351 (b) declaring the message to be delivered, issuing a "deliv- 352 ered" tracking status, re-sending the message to the confi- 353 dential forwarding address, and disabling further message 354 tracking requests. 356 The tracking algorithms MUST NOT allow tracking through 357 list expansions. When a message is delivered to a list, a 358 tracking request MUST respond with an "expanded" tracking status 359 and MUST NOT display the contents of the list. 361 5. References 363 [DRAFT-MTRK-MODEL] 364 T. Hansen, ``Message Tracking Model and Requirements.'' 365 draft-ietf-msgtrk-model-03.txt. November 2000. 367 [DRAFT-MTRK-MTQP] 368 T. Hansen, ``Message Tracking Query Protocol.'' draft-ietf- 369 msgtrk-mtqp-01.txt. November 2000. 371 [DRAFT-MTRK-SMTPEXT] 372 E. Allman, ``SMTP Service Extension for Message Tracking.'' 373 draft-ietf-msgtrk-smtpext-00.txt. December 2000. 375 [RFC-ABNF] 376 Crocker, D., Editor, and P. Overell, ``Augmented BNF for Syn- 377 tax Specifications: ABNF'', RFC 2234, November 1997. 379 [RFC-DSN-REPT] 380 G. Vaudreuil, ``The Multipart/Report Content Type for the 381 Reporting of Mail System Administrative Messages.'' RFC 1892. 382 January 1996. 384 [RFC-DSN-SMTP] 385 K. Moore, ``SMTP Service Extension for Delivery Status Notifi- 386 cations.'' RFC 1891. January 1996. 388 [RFC-DSN-STAT] 389 K. Moore and G. Vaudreuil, ``An Extensible Message Format for 390 Delivery Status Notifications.'' RFC 1894. January 1996. 392 [RFC-EMSSC] 393 G. Vaudreuil, ``Enhanced Mail System Status Codes.'' RFC 394 1893. January 1996. 396 [RFC-ESMTP] 397 Rose, M., Stefferud, E., Crocker, D., Klensin, J. and N. 398 Freed, ``SMTP Service Extensions.'' STD 10, RFC 1869. Novem- 399 ber 1995. 401 [RFC-HOSTREQ] 402 R. Braden (ed.), ``Requirements for Internet Hosts -- Applica- 403 tion and Support.'' STD 3, RFC 1123. October 1989. 405 [RFC-KEYWORDS] 406 S. Bradner, ``Key words for use in RFCs to Indicate Require- 407 ment Levels.'' RFC 2119. March 1997. 409 [RFC-LMTP] 410 J. Myers, ``Local Mail Transfer Protocol.'' RFC 2033. Octo- 411 ber 1996. 413 [RFC-MDN] 414 R. Fajman, ``An Extensible Message Format for Message Disposi- 415 tion Notifications.'' RFC 2298. March 1998. 417 [RFC-MIME] 418 N. Freed and N. Borenstein, ``Multipurpose Internet Mail 419 Extensions (MIME) Part One: Format of Internet Message Bod- 420 ies.'' RFC 2045. November 1996. 422 [RFC-MSGFMT] 423 D. Crocker, ``Standard for the Format of ARPA Internet Text 424 Messages.'' RFC 822. August 1982. 426 [RFC-RELATED] 427 E. Levinson, ``The MIME Multipart/Related Content-type.'' RFC 428 2387. August 1998. 430 6. Author's Address 432 Eric Allman 433 Sendmail, Inc. 434 6603 Shellmound 435 Emeryville, CA 94608 436 U.S.A. 438 E-Mail: eric@Sendmail.COM 439 Phone: +1 510 594 5501 440 Fax: +1 510 594 5411