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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) -- Possible downref: Non-RFC (?) normative reference: ref. 'ISO-8859-1' ** Obsolete normative reference: RFC 2616 (Obsoleted by RFC 7230, RFC 7231, RFC 7232, RFC 7233, RFC 7234, RFC 7235) ** Obsolete normative reference: RFC 5987 (Obsoleted by RFC 8187) -- Obsolete informational reference (is this intentional?): RFC 2388 (Obsoleted by RFC 7578) Summary: 2 errors (**), 0 flaws (~~), 1 warning (==), 5 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 HTTPbis Working Group J. Reschke 3 Internet-Draft greenbytes 4 Updates: 2616 (if approved) February 26, 2011 5 Intended status: Standards Track 6 Expires: August 30, 2011 8 Use of the Content-Disposition Header Field in the 9 Hypertext Transfer Protocol (HTTP) 10 draft-ietf-httpbis-content-disp-06 12 Abstract 14 RFC 2616 defines the Content-Disposition response header field, but 15 points out that it is not part of the HTTP/1.1 Standard. This 16 specification takes over the definition and registration of Content- 17 Disposition, as used in HTTP, and clarifies internationalization 18 aspects. 20 Editorial Note (To be removed by RFC Editor before publication) 22 This specification is expected to replace the definition of Content- 23 Disposition in the HTTP/1.1 specification, as currently revised by 24 the IETF HTTPbis working group. See also 25 . 27 Discussion of this draft should take place on the HTTPBIS working 28 group mailing list (ietf-http-wg@w3.org). The current issues list is 29 at and related documents (including fancy 31 diffs) can be found at . 33 The changes in this draft are summarized in Appendix E.10. 35 Status of This Memo 37 This Internet-Draft is submitted in full conformance with the 38 provisions of BCP 78 and BCP 79. 40 Internet-Drafts are working documents of the Internet Engineering 41 Task Force (IETF). Note that other groups may also distribute 42 working documents as Internet-Drafts. The list of current Internet- 43 Drafts is at http://datatracker.ietf.org/drafts/current/. 45 Internet-Drafts are draft documents valid for a maximum of six months 46 and may be updated, replaced, or obsoleted by other documents at any 47 time. It is inappropriate to use Internet-Drafts as reference 48 material or to cite them other than as "work in progress." 49 This Internet-Draft will expire on August 30, 2011. 51 Copyright Notice 53 Copyright (c) 2011 IETF Trust and the persons identified as the 54 document authors. All rights reserved. 56 This document is subject to BCP 78 and the IETF Trust's Legal 57 Provisions Relating to IETF Documents 58 (http://trustee.ietf.org/license-info) in effect on the date of 59 publication of this document. Please review these documents 60 carefully, as they describe your rights and restrictions with respect 61 to this document. Code Components extracted from this document must 62 include Simplified BSD License text as described in Section 4.e of 63 the Trust Legal Provisions and are provided without warranty as 64 described in the Simplified BSD License. 66 Table of Contents 68 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 69 2. Notational Conventions . . . . . . . . . . . . . . . . . . . . 4 70 3. Conformance and Error Handling . . . . . . . . . . . . . . . . 4 71 4. Header Field Definition . . . . . . . . . . . . . . . . . . . 5 72 4.1. Grammar . . . . . . . . . . . . . . . . . . . . . . . . . 5 73 4.2. Disposition Type . . . . . . . . . . . . . . . . . . . . . 6 74 4.3. Disposition Parameter: 'Filename' . . . . . . . . . . . . 6 75 4.4. Disposition Parameter: Extensions . . . . . . . . . . . . 7 76 4.5. Extensibility . . . . . . . . . . . . . . . . . . . . . . 7 77 5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 78 6. Internationalization Considerations . . . . . . . . . . . . . 8 79 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9 80 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 81 8.1. Registry for Disposition Values and Parameter . . . . . . 9 82 8.2. Header Field Registration . . . . . . . . . . . . . . . . 9 83 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 84 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9 85 10.1. Normative References . . . . . . . . . . . . . . . . . . . 9 86 10.2. Informative References . . . . . . . . . . . . . . . . . . 10 87 Appendix A. Changes from the RFC 2616 Definition . . . . . . . . 10 88 Appendix B. Differences compared to RFC 2183 . . . . . . . . . . 11 89 Appendix C. Alternative Approaches to Internationalization . . . 11 90 C.1. RFC 2047 Encoding . . . . . . . . . . . . . . . . . . . . 11 91 C.2. Percent Encoding . . . . . . . . . . . . . . . . . . . . . 12 92 C.3. Encoding Sniffing . . . . . . . . . . . . . . . . . . . . 12 93 C.4. Implementations (to be removed by RFC Editor before 94 publication) . . . . . . . . . . . . . . . . . . . . . . . 12 95 Appendix D. Advice on Generating Content-Disposition Header 96 Fields . . . . . . . . . . . . . . . . . . . . . . . 13 97 Appendix E. Change Log (to be removed by RFC Editor before 98 publication) . . . . . . . . . . . . . . . . . . . . 14 99 E.1. Since draft-reschke-rfc2183-in-http-00 . . . . . . . . . . 14 100 E.2. Since draft-reschke-rfc2183-in-http-01 . . . . . . . . . . 14 101 E.3. Since draft-reschke-rfc2183-in-http-02 . . . . . . . . . . 14 102 E.4. Since draft-reschke-rfc2183-in-http-03 . . . . . . . . . . 15 103 E.5. Since draft-ietf-httpbis-content-disp-00 . . . . . . . . . 15 104 E.6. Since draft-ietf-httpbis-content-disp-01 . . . . . . . . . 15 105 E.7. Since draft-ietf-httpbis-content-disp-02 . . . . . . . . . 15 106 E.8. Since draft-ietf-httpbis-content-disp-03 . . . . . . . . . 15 107 E.9. Since draft-ietf-httpbis-content-disp-04 . . . . . . . . . 16 108 E.10. Since draft-ietf-httpbis-content-disp-05 . . . . . . . . . 16 109 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 111 1. Introduction 113 RFC 2616 defines the Content-Disposition response header field in 114 Section 19.5.1 of [RFC2616], but points out that it is not part of 115 the HTTP/1.1 Standard (Section 15.5): 117 Content-Disposition is not part of the HTTP standard, but since it 118 is widely implemented, we are documenting its use and risks for 119 implementers. 121 This specification takes over the definition and registration of 122 Content-Disposition, as used in HTTP. Based on interoperability 123 testing with existing User Agents, it fully defines a profile of the 124 features defined in the Multipurpose Internet Mail Extensions (MIME) 125 variant ([RFC2183]) of the header field, and also clarifies 126 internationalization aspects. 128 Note: this document does not apply to Content-Disposition header 129 fields appearing in payload bodies transmitted over HTTP, such as 130 when using the media type "multipart/form-data" ([RFC2388]). 132 2. Notational Conventions 134 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 135 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 136 document are to be interpreted as described in [RFC2119]. 138 This specification uses the augmented BNF notation defined in Section 139 2.1 of [RFC2616], including its rules for implied linear whitespace 140 (LWS). 142 3. Conformance and Error Handling 144 This specification defines conformance criteria for both senders 145 (usually, HTTP origin servers) and recipients (usually, HTTP user 146 agents) of the Content-Disposition header field. An implementation 147 is considered conformant if it complies with all of the requirements 148 associated with its role. 150 This specification also defines certain forms of the header field- 151 value to be invalid, using both ABNF and prose requirements, but it 152 does not define special handling of these invalid field-values. 154 Senders MUST NOT generate Content-Disposition header fields that are 155 invalid. 157 Recipients MAY take steps to recover a usable field-value from an 158 invalid header field, but SHOULD NOT reject the message outright, 159 unless this is explicitly desirable behaviour (e.g., the 160 implementation is a validator). As such, the default handling of 161 invalid fields is to ignore them. 163 4. Header Field Definition 165 The Content-Disposition response header field is used to convey 166 additional information about how to process the response payload, and 167 also can be used to attach additional metadata, such as the filename 168 to use when saving the response payload locally. 170 4.1. Grammar 172 content-disposition = "Content-Disposition" ":" 173 disposition-type *( ";" disposition-parm ) 175 disposition-type = "inline" | "attachment" | disp-ext-type 176 ; case-insensitive 177 disp-ext-type = token 179 disposition-parm = filename-parm | disp-ext-parm 181 filename-parm = "filename" "=" value 182 | "filename*" "=" ext-value 184 disp-ext-parm = token "=" value 185 | ext-token "=" ext-value 186 ext-token = 188 Defined in [RFC2616]: 190 token = 191 quoted-string = 192 value = 193 ; token | quoted-string 195 Defined in [RFC5987]: 197 ext-value = 199 Header field values with multiple instances of the same parameter 200 name are invalid. 202 Note that due to the rules for implied linear whitespace (Section 2.1 203 of [RFC2616]), OPTIONAL whitespace can appear between words (token or 204 quoted-string) and separator characters. 206 Furthermore note that the format used for ext-value allows specifying 207 a natural language; this is of limited use for filenames and is 208 likely to be ignored by recipients. 210 4.2. Disposition Type 212 If the disposition type matches "attachment" (case-insensitively), 213 this indicates that the recipient should prompt the user to save the 214 response locally, rather than process it normally (as per its media 215 type). 217 On the other hand, if it matches "inline" (case-insensitively), this 218 implies default processing. Therefore, the disposition type "inline" 219 is only useful when it is augmented with additional parameters, such 220 as the filename (see below). 222 Unknown or unhandled disposition types SHOULD be handled by 223 recipients the same way as "attachment" (see also [RFC2183], Section 224 2.8). 226 4.3. Disposition Parameter: 'Filename' 228 The parameters "filename" and "filename*", to be matched case- 229 insensitively, provide information on how to construct a filename for 230 storing the message payload. 232 Depending on the disposition type, this information might be used 233 right away (in the "save as..." interaction caused for the 234 "attachment" disposition type), or later on (for instance, when the 235 user decides to save the contents of the current page being 236 displayed). 238 The parameters "filename" and "filename*" differ only in that 239 "filename*" uses the encoding defined in [RFC5987], allowing the use 240 of characters not present in the ISO-8859-1 character set 241 ([ISO-8859-1]). 243 Many user agent implementations predating this specification do not 244 understand the "filename*" parameter. Therefore, when both 245 "filename" and "filename*" are present in a single header field 246 value, recipients SHOULD pick "filename*" and ignore "filename". 247 This way, senders can avoid special-casing specific user agents by 248 sending both the more expressive "filename*" parameter, and the 249 "filename" parameter as fallback for legacy recipients (see Section 5 250 for an example). 252 It is essential that recipients treat the specified filename as 253 advisory only, thus be very careful in extracting the desired 254 information. In particular: 256 o When the value contains path separator characters ("\" or "/"), 257 recipients SHOULD ignore all but the last path segment. This 258 prevents unintentional overwriting of well-known file system 259 locations (such as "/etc/passwd"). 261 o Many platforms do not use Internet Media Types ([RFC2046]) to hold 262 type information in the file system, but rely on filename 263 extensions instead. Trusting the server-provided file extension 264 could introduce a privilege escalation when the saved file is 265 later opened (consider ".exe"). Thus, recipients need to ensure 266 that a file extension is used that is safe, optimally matching the 267 media type of the received payload. 269 o Recipients are advised to strip or replace character sequences 270 that are known to cause confusion both in user interfaces and in 271 filenames, such as control characters and leading and trailing 272 whitespace. 274 o Other aspects recipients need to be aware of are names that have a 275 special meaning in the file system or in shell commands, such as 276 "." and "..", "~", "|", and also device names. 278 Note: Many user agents do not properly handle the escape character 279 "\" when using the quoted-string form. Furthermore, some user 280 agents erroneously try to perform unescaping of "percent" escapes 281 (see Appendix C.2), and thus might misinterpret filenames 282 containing the percent character followed by two hex digits. 284 4.4. Disposition Parameter: Extensions 286 To enable future extensions, recipients SHOULD ignore unrecognized 287 parameters (see also [RFC2183], Section 2.8). 289 4.5. Extensibility 291 Note that Section 9 of [RFC2183] defines IANA registries both for 292 disposition types and disposition parameters. This registry is 293 shared by different protocols using Content-Disposition, such as MIME 294 and HTTP. Therefore, not all registered values may make sense in the 295 context of HTTP. 297 5. Examples 299 Direct UA to show "save as" dialog, with a filename of 300 "example.html": 302 Content-Disposition: Attachment; filename=example.html 304 Direct UA to behave as if the Content-Disposition header field wasn't 305 present, but to remember the filename "an example.html" for a 306 subsequent save operation: 308 Content-Disposition: INLINE; FILENAME= "an example.html" 310 Note: this uses the quoted-string form so that the space character 311 can be included. 313 Direct UA to show "save as" dialog, with a filename containing the 314 Unicode character U+20AC (EURO SIGN): 316 Content-Disposition: attachment; 317 filename*= UTF-8''%e2%82%ac%20rates 319 Here, the encoding defined in [RFC5987] is also used to encode the 320 non-ISO-8859-1 character. 322 Same as above, but adding the "filename" parameter for compatibility 323 with user agents not implementing RFC 5987: 325 Content-Disposition: attachment; 326 filename="EURO rates"; 327 filename*=utf-8''%e2%82%ac%20rates 329 Note: those user agents that do not support the RFC 5987 encoding 330 ignore "filename*" when it occurs after "filename". 332 6. Internationalization Considerations 334 The "filename*" parameter (Section 4.3), using the encoding defined 335 in [RFC5987], allows the server to transmit characters outside the 336 ISO-8859-1 character set, and also to optionally specify the language 337 in use. 339 Future parameters might also require internationalization, in which 340 case the same encoding can be used. 342 7. Security Considerations 344 Using server-supplied information for constructing local filenames 345 introduces many risks. These are summarized in Section 4.3. 347 Furthermore, implementers also ought to be aware of the Security 348 Considerations applying to HTTP (see Section 15 of [RFC2616]), and 349 also the parameter encoding defined in [RFC5987] (see Section 5). 351 8. IANA Considerations 353 8.1. Registry for Disposition Values and Parameter 355 This specification does not introduce any changes to the registration 356 procedures for disposition values and parameters that are defined in 357 Section 9 of [RFC2183]. 359 8.2. Header Field Registration 361 This document updates the definition of the Content-Disposition HTTP 362 header field in the permanent HTTP header field registry (see 363 [RFC3864]). 365 Header field name: Content-Disposition 367 Applicable protocol: http 369 Status: standard 371 Author/Change controller: IETF 373 Specification document: this specification (Section 4) 375 9. Acknowledgements 377 Thanks to Adam Barth, Rolf Eike Beer, Bjoern Hoehrmann, Alfred 378 Hoenes, Roar Lauritzsen, Henrik Nordstrom, and Mark Nottingham for 379 their valuable feedback. 381 10. References 383 10.1. Normative References 385 [ISO-8859-1] International Organization for Standardization, 386 "Information technology -- 8-bit single-byte coded 387 graphic character sets -- Part 1: Latin alphabet No. 388 1", ISO/IEC 8859-1:1998, 1998. 390 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 391 Requirement Levels", BCP 14, RFC 2119, March 1997. 393 [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., 394 Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext 395 Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. 397 [RFC5987] Reschke, J., "Character Set and Language Encoding for 398 Hypertext Transfer Protocol (HTTP) Header Field 399 Parameters", RFC 5987, August 2010. 401 10.2. Informative References 403 [RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet 404 Mail Extensions (MIME) Part Two: Media Types", 405 RFC 2046, November 1996. 407 [RFC2047] Moore, K., "MIME (Multipurpose Internet Mail 408 Extensions) Part Three: Message Header Extensions for 409 Non-ASCII Text", RFC 2047, November 1996. 411 [RFC2183] Troost, R., Dorner, S., and K. Moore, "Communicating 412 Presentation Information in Internet Messages: The 413 Content-Disposition Header Field", RFC 2183, 414 August 1997. 416 [RFC2231] Freed, N. and K. Moore, "MIME Parameter Value and 417 Encoded Word Extensions: Character Sets, Languages, and 418 Continuations", RFC 2231, November 1997. 420 [RFC2388] Masinter, L., "Returning Values from Forms: multipart/ 421 form-data", RFC 2388, August 1998. 423 [RFC3864] Klyne, G., Nottingham, M., and J. Mogul, "Registration 424 Procedures for Message Header Fields", BCP 90, 425 RFC 3864, September 2004. 427 [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, 428 "Uniform Resource Identifier (URI): Generic Syntax", 429 STD 66, RFC 3986, January 2005. 431 Appendix A. Changes from the RFC 2616 Definition 433 Compared to Section 19.5.1 of [RFC2616], the following normative 434 changes reflecting actual implementations have been made: 436 o According to RFC 2616, the disposition type "attachment" only 437 applies to content of type "application/octet-stream". This 438 restriction has been removed, because recipients in practice do 439 not check the content type, and it also discourages properly 440 declaring the media type. 442 o RFC 2616 only allows "quoted-string" for the filename parameter. 443 This would be an exceptional parameter syntax, and also doesn't 444 reflect actual use. 446 o The definition for the disposition type "inline" ([RFC2183], 447 Section 2.1) has been re-added with a suggestion for its 448 processing. 450 o This specification requires support for the extended parameter 451 encoding defined in [RFC5987]. 453 Appendix B. Differences compared to RFC 2183 455 Section 2 of [RFC2183] defines several additional disposition 456 parameters: "creation-date", "modification-date", "quoted-date-time", 457 and "size". The majority of user agents does not implement these, 458 thus they have been omitted from this specification. 460 Appendix C. Alternative Approaches to Internationalization 462 By default, HTTP header field parameters cannot carry characters 463 outside the ISO-8859-1 ([ISO-8859-1]) character encoding (see 464 [RFC2616], Section 2.2). For the "filename" parameter, this of 465 course is an unacceptable restriction. 467 Unfortunately, user agent implementers have not managed to come up 468 with an interoperable approach, although the IETF Standards Track 469 specifies exactly one solution ([RFC2231], clarified and profiled for 470 HTTP in [RFC5987]). 472 For completeness, the sections below describe the various approaches 473 that have been tried, and explains how they are inferior to the RFC 474 5987 encoding used in this specification. 476 C.1. RFC 2047 Encoding 478 RFC 2047 defines an encoding mechanism for header fields, but this 479 encoding is not supposed to be used for header field parameters - see 480 Section 5 of [RFC2047]: 482 An 'encoded-word' MUST NOT appear within a 'quoted-string'. 484 ... 486 An 'encoded-word' MUST NOT be used in parameter of a MIME Content- 487 Type or Content-Disposition field, or in any structured field body 488 except within a 'comment' or 'phrase'. 490 In practice, some user agents implement the encoding, some do not 491 (exposing the encoded string to the user), and some get confused by 492 it. 494 C.2. Percent Encoding 496 Some user agents accept percent encoded ([RFC3986], Section 2.1) 497 sequences of characters. The character encoding being used for 498 decoding depends on various factors, including the encoding of the 499 referring page, the user agent's locale, its configuration, and also 500 the actual value of the parameter. 502 In practice, this is hard to use because those user agents that do 503 not support it will display the escaped character sequence to the 504 user. For those user agents that do implement this it is difficult 505 to predict what character encoding they actually expect. 507 C.3. Encoding Sniffing 509 Some user agents inspect the value (which defaults to ISO-8859-1 for 510 the quoted-string form) and switch to UTF-8 when it seems to be more 511 likely to be the correct interpretation. 513 As with the approaches above, this is not interoperable and 514 furthermore risks misinterpreting the actual value. 516 C.4. Implementations (to be removed by RFC Editor before publication) 518 Unfortunately, as of February 2011, neither the encoding defined in 519 RFCs 2231 and 5987, nor any of the alternate approaches discussed 520 above was implemented interoperably. Thus, this specification 521 recommends the approach defined in RFC 5987, which at least has the 522 advantage of actually being specified properly. 524 The table below shows the implementation support for the various 525 approaches: 527 +---------------+------------+--------+--------------+--------------+ 528 | User Agent | RFC | RFC | Percent | Encoding | 529 | | 2231/5987 | 2047 | Encoding | Sniffing | 530 +---------------+------------+--------+--------------+--------------+ 531 | Chrome | yes | yes | yes | yes | 532 | Firefox | yes (*) | yes | no | yes | 533 | Internet | yes (**) | no | yes | no | 534 | Explorer | | | | | 535 | Konqueror | yes | no | no | no | 536 | Opera | yes | no | no | no | 537 | Safari | no | no | no | yes | 538 +---------------+------------+--------+--------------+--------------+ 540 (*) Does not implement the fallback behavior to "filename" described 541 in Section 4.3; a fix is planned for Firefox 5. 543 (**) Starting with IE9RC, but only implements UTF-8. 545 Appendix D. Advice on Generating Content-Disposition Header Fields 547 To successfully interoperate with existing and future user agents, 548 senders of the Content-Disposition header field are advised to: 550 o Include a "filename" parameter when US-ASCII is sufficiently 551 expressive. 553 o Use the 'token' form of the filename parameter only when it does 554 not contain disallowed characters (e.g., spaces); in such cases, 555 the quoted-string form should be used. 557 o Avoid including the percent character followed by two hexadecimal 558 characters (e.g., %A9) in the filename parameter, since some 559 existing implementations consider it to be an escape character, 560 while others will pass it through unchanged. 562 o Avoid including the "\" character in the quoted-string form of the 563 filename parameter, as escaping is not implemented by some user 564 agents, and can be considered as an illegal path character. 566 o Avoid using non-ASCII characters in the filename parameter. 567 Although most existing implementations will decode them as ISO- 568 8859-1, some will apply heuristics to detect UTF-8, and thus might 569 fail on certain names. 571 o Include a "filename*" parameter where the desired filename cannot 572 be expressed faithfully using the "filename" form. Note that 573 legacy user agents will not process this, and will fall back to 574 using the "filename" parameter's content. 576 o When a "filename*" parameter is sent, to also generate a 577 "filename" parameter as a fallback for user agents that do not 578 support the "filename*" form, if possible. This can be done by 579 substituting characters with US-ASCII sequences (e.g., Unicode 580 character point U+00E4 (LATIN SMALL LETTER A WITH DIARESIS) by 581 "ae"). Note that this may not be possible in some locales. 583 o When a "filename" parameter is included as a fallback (as per 584 above), "filename" should occur first, due to parsing problems in 585 some existing implementations. [[fallbackbug: Firefox is known to 586 pick the wrong parameter; a bug fix is scheduled for Firefox 5. 587 --jre]] 589 o Use UTF-8 as the encoding of the "filename*" parameter, when 590 present, because at least one existing implementation only 591 implements that encoding. 593 Note that this advice is based upon UA behaviour at the time of 594 writing, and might be superseded. 595 provides an 596 overview of current levels of support in various implementations. 598 Appendix E. Change Log (to be removed by RFC Editor before publication) 600 Note: the issues names in the change log entries for 601 draft-reschke-rfc2183-in-http refer to . 604 E.1. Since draft-reschke-rfc2183-in-http-00 606 Adjust terminology ("header" -> "header field"). Update rfc2231-in- 607 http reference. 609 E.2. Since draft-reschke-rfc2183-in-http-01 611 Update rfc2231-in-http reference. Actually define the "filename" 612 parameter. Add internationalization considerations. Add examples 613 using the RFC 5987 encoding. Add overview over other approaches, 614 plus a table reporting implementation status. Add and resolve issue 615 "nodep2183". Add issues "asciivsiso", "deplboth", "quoted", and 616 "registry". 618 E.3. Since draft-reschke-rfc2183-in-http-02 620 Add and close issue "docfallback". Close issues "asciivsiso", 621 "deplboth", "quoted", and "registry". 623 E.4. Since draft-reschke-rfc2183-in-http-03 625 Updated to be a Working Draft of the IETF HTTPbis Working Group. 627 E.5. Since draft-ietf-httpbis-content-disp-00 629 Closed issues: 631 o : "handling of 632 unknown disposition types" 634 Slightly updated the notes about the proposed fallback behavior. 636 E.6. Since draft-ietf-httpbis-content-disp-01 638 Various editorial improvements. 640 E.7. Since draft-ietf-httpbis-content-disp-02 642 Closed issues: 644 o : "state that 645 repeating parameters are invalid" 647 o : "warn about 648 %xx in filenames being misinterpreted" 650 o : "mention 651 control chars when talking about postprecessing the filename 652 parameter" 654 Update Appendix C.4; Opera 10.63 RC implements the recommended 655 fallback behavior. 657 E.8. Since draft-ietf-httpbis-content-disp-03 659 Closed issues: 661 o : 662 "'modification-date' *is* implemented in Konq 4.5" 664 o : "clarify what 665 LWS means for the Content-Disp grammar" 667 o : "Avoid passive 668 voice in message requirements" 670 o : "text about 671 historical percent-decoding unclear" 673 o : "add 674 explanation of language tagging" 676 o : "Clarify that 677 C-D spec does not apply to multipart upload" 679 E.9. Since draft-ietf-httpbis-content-disp-04 681 Updated implementation information (Chrome 9 implements RFC 5987, IE 682 9 RC implements it for UTF-8 only). 684 Clarify who requirements are on, add a section discussing conformance 685 and handling of invalid field values in general. 687 Closed issues: 689 o : "avoid 690 stating ISO-8859-1 default for header param" (the default is still 691 mentioned, but it was clarified what it applies to). 693 o : "Path 694 Separator Characters" 696 E.10. Since draft-ietf-httpbis-content-disp-05 698 Editorial changes: Fixed two typos where the new Conformance section 699 said "Content-Location" instead of "Content-Disposition". Cleaned up 700 terminology ("user agent", "recipient", "sender", "message body", 701 ...). Stated what the escape character for quoted-string is. 702 Explained a use case for "inline" disposition type. Updated 703 implementation notes with respect to the fallback behavior. 705 Added appendix "Advice on Generating Content-Disposition Header 706 Fields". 708 Index 710 C 711 Content-Disposition header field 5 713 H 714 Header Fields 715 Content-Disposition 5 717 Author's Address 719 Julian F. Reschke 720 greenbytes GmbH 721 Hafenweg 16 722 Muenster, NW 48155 723 Germany 725 EMail: julian.reschke@greenbytes.de 726 URI: http://greenbytes.de/tech/webdav/