Network Working Group C. Newman Internet-Draft Sun Microsystems Expires: June 24, 2003 A. Melnikov ACI Worldwide/MessagingDirect December 24, 2002 ACAP Media Type Dataset Class draft-ietf-acap-mediatype-01.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http:// www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on June 24, 2003. Copyright Notice Copyright (C) The Internet Society (2002). All Rights Reserved. Abstract With the definition of standardized media types in MIME it has become necessary to keep mapping tables which translate between the standard media type names, commonly used file name extensions, any platform specific typing mechanism, and helper applications to view, compose, edit or print media types. Supplying a set of site defaults is useful so that users won't have to configure well-known types. The mailcap mechanism provides some of this functionality in a homogeneous environment with a shared file system, and both the Macintosh program "Internet Config" and the Windows Registry have had some success in consolidating these tables for multiple applications Newman & Melnikov Expires June 24, 2003 [Page 1] Internet-Draft ACAP Media Type Dataset Class December 2002 on a single machine. But neither of these addresses the problems of multi-platform users or a heterogeneous environment. Application Configuration Access Protocol (ACAP) provides appropriate facilities for this need. ACAP's dataset structure is extensible and ACAP's inheritance feature provides for enterprise default settings with per-user customization. This memo defines an ACAP dataset class for media type mapping tables. Table of Contents 1. Conventions used in this document . . . . . . . . . . . . . 3 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 3. ACAP Media Type Dataset Class . . . . . . . . . . . . . . . 3 3.1 ACAP Media Type Dataset Class Prefix . . . . . . . . . . . . 3 3.2 ACAP Media Type Dataset Hierarchy . . . . . . . . . . . . . 3 4. Recommended ACAP Media Type Attributes . . . . . . . . . . . 3 4.1 Basic Attributes . . . . . . . . . . . . . . . . . . . . . . 4 4.2 System Independent Attributes . . . . . . . . . . . . . . . 4 4.3 MacOS Attributes . . . . . . . . . . . . . . . . . . . . . . 7 4.4 Unix Attributes . . . . . . . . . . . . . . . . . . . . . . 9 4.5 Microsoft Windows Attributes . . . . . . . . . . . . . . . . 12 4.5.1 Mapping MediaTypes to Windows Registry . . . . . . . . . . . 15 5. Usage Procedures . . . . . . . . . . . . . . . . . . . . . . 15 6. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 17 7. Security Considerations . . . . . . . . . . . . . . . . . . 17 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . 18 Normative References . . . . . . . . . . . . . . . . . . . . 18 Informative References . . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 19 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Intellectual Property and Copyright Statements . . . . . . . 22 Newman & Melnikov Expires June 24, 2003 [Page 2] Internet-Draft ACAP Media Type Dataset Class December 2002 1. Conventions used in this document The key words "MUST", "MUST NOT", "SHOULD", "SHOULD NOT", and "MAY" in this document are to be interpreted as defined in "Key words for use in RFCs to Indicate Requirement Levels" [3]. The attribute syntax specifications use the Augmented Backus-Naur Form (ABNF) [5] notation including rules from ACAP [6]. 2. Introduction With the definition of standardized media types in MIME [2] it has become necessary to keep mapping tables which translate between the standard media type names, commonly used file name extensions, any platform specific typing mechanism, and helper applications to view, compose, edit or print media types. Supplying a set of site defaults is useful so that users won't have to configure well-known types. The mailcap [8] mechanism provides some of this functionality in a homogeneous environment with a shared file system, and both the Macintosh program "Internet Config" and the Windows Registry have had some success in consolidating these tables for multiple applications on a single machine. But neither of these addresses the problems of multi-platform users or a heterogeneous environment. ACAP [6] provides appropriate facilities for this need. ACAP's dataset structure is extensible and ACAP's inheritance feature provides for enterprise default settings with per-user customization. 3. ACAP Media Type Dataset Class 3.1 ACAP Media Type Dataset Class Prefix Datasets whose names begin with "/mediatype" are assumed to contain mediatype entries as defined in this specification. 3.2 ACAP Media Type Dataset Hierarchy Each user may have a set of named media type profiles for use on different hosts. The default is "default" and is referenced with the path "/mediatype/user//default/". Inheritance is likely to be useful both for inheriting site or group defaults as well as for inheriting the default configuration when using different hosts. 4. Recommended ACAP Media Type Attributes A mediatype entry MUST have an "entry" attribute. All other attributes are OPTIONAL. Newman & Melnikov Expires June 24, 2003 [Page 3] Internet-Draft ACAP Media Type Dataset Class December 2002 The ABNF defines the content of the attribute values prior to their encoding as an ACAP string. Clients MUST conform to the syntax when generating these attributes, but MUST NOT assume that the attribute values will conform to this syntax on access. Servers SHOULD NOT enforce the syntax. The OS-specific entries define a number of basic actions which may be performed on a media type. The intention is that additional actions may be added in the future following the same template as the existing actions. 4.1 Basic Attributes These attributes are defined in ACAP [6] and have meaning in all dataset classes. This section describes how they are used in a mediatype dataset. entry The "entry" attribute is used to hold a short descriptive name of the media type. This name is used for inheritance, so when customizing a media type which has an entry in an inherited dataset, the entry name needs to remain the same. subdataset The "subdataset" attribute indicates there is another media type dataset underneath this entry. 4.2 System Independent Attributes These attributes are likely to have meaning for all ACAP clients. mediatype.common.type This contains the MIME media type [2] of the entry. New MIME media types are registered according to the MIME registration procedures [11]. The ABNF terminals type and subtype are defined in MIME Internet Message Bodies [1]. Free insertion of linear-white-space is not permitted in this grammar. Newman & Melnikov Expires June 24, 2003 [Page 4] Internet-Draft ACAP Media Type Dataset Class December 2002 A subtype of "*" indicates a catch-all entry for a type. Clients SHOULD check for a catch-all entry after checking for a regular entry. Catch-all entries are used only for locating a helper application, so the extension attributes SHOULD be NIL. mtype-typenam = type "/" mtype-subtype mtype-subtype = subtype / "*" mediatype.common.param. This contains a MIME parameter for the entry. For example, there might be multiple entries for text media types with different charset parameters. The portion of the attribute name matches the ABNF for the "attribute" rule in [1] but MUST be all lower case. MIME parameter value encodings [4] SHOULD be decoded prior to use of these attributes. mtype-param = *UTF8-CHAR mediatype.common.extension This contains the primary file name extension used with this media type. Extensions should be converted to lower case to simplify searching. The leading "." before an extension is not included in this attribute value. mtype-ext = 1*ATOM-CHAR mediatype.common.extensionOther This is a multi-valued attribute which contains additional file name extension(s) that are commonly associated with this media type. For example, with JPEG files (image/jpeg), a number of extensions have been observed: "jpg", "jpeg", "jfif", "jpe" and "jfi". Extensions should be converted to lower case to simplify searching. mtype-extother = 1*ATOM-CHAR mediatype.common.magicNumber.bin This contains the magic number(s) of the media type. A magic number is a set of octets at the beginning of the file which are always the same for that media type. For example, all image/gif objects begin with the four-octet sequence (71, 73, 70, 56 or "GIF8"). As this is a binary field, it may contain any octet value including 0. This can be used to attempt to locate a type Newman & Melnikov Expires June 24, 2003 [Page 5] Internet-Draft ACAP Media Type Dataset Class December 2002 for an untyped file. mtype-magic = 1*OCTET mediatype.common.textualNewlines If this is "1" it indicates that the media type is line oriented and subject to newline canonicalization. If this is "0" it indicates newlines should be preserved. If NIL, the client should default this to "0" for non-text types and "1" for text types. mtype-text = "0" / "1" mediatype.common.description This is a longer textual description of the mediatype. Newlines are represented by a CRLF sequence. mtype-desc = *UTF8-CHAR mediatype.common.suppressWarning If this is "1" then no security warnings will be issued to the user on any platform. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-suppress = "0" / "1" mediatype.common.preferred If this is "1" it indicates that this is the preferred entry for a media type with multiple entries. If this is "0", it indicates this is not the preferred entry. NIL indicates an unspecified preference. For example, the "text/plain" media type may be used to represent multiple file types including plain text and C source files. Thus there can be multiple text/plain entries in the mediatypes list and this attribute is used to identify which one to use by preference when a single choice must be made. As ACAP does not enforce uniqueness of this attribute, software which uses this attribute needs a strategy to deal with multiple preferred types, such as choosing the type whose "entry" appears first using the client's comparator preference. mtype-preferred = "0" / "1" Newman & Melnikov Expires June 24, 2003 [Page 6] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.common.MIME If this is a "1" it indicates the type is represented as a MIME entity (including headers) rather than as a MIME body. If this is "0", it indicates the type is represented only as a MIME body. If this is NIL, the client should treat it as "0" for non-multipart types and "1" for multipart types. Action-specific ".MIME" attributes take precedence over this when they are non-NIL. mtype-mime = "0" / "1" 4.3 MacOS Attributes These are attributes which apply to MacOS systems. mediatype.macOS.type.bin This contains the 4-octet MacOS type code for this media type. mtype-mactype = 4OCTET mediatype.macOS.creator.bin This contains the 4-octet MacOS creator code which the user prefers for use with documents of this type. mtype-maccreat = 4OCTET mediatype.macOS.creator.name This contains the name of the application whose creator code is stored in mediatype.macOS.creator.bin. This value MUST be UTF-8 and not in another MacOS script or character set. mtype-maccname = 1*UTF8-CHAR mediatype.macOS.creator.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when launching the application referenced by the creator code. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-maccsuppress = "0" / "1" Newman & Melnikov Expires June 24, 2003 [Page 7] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.macOS.action.postProcess.bin This contains the 4-octet MacOS creator code of an application which the user wishes to use when post-processing documents of this type. If NIL, then no post-processing is required. This is primarily used for encapsulating formats such as application/ applefile. mtype-macpost = 4OCTET mediatype.macOS.action.postProcess.name This contains the filename of the application whose creator code is stored in mediatype.macOS.postProcess.bin. This value MUST be UTF-8 and not in another MacOS script or character set. mtype-macpname = 1*UTF8-CHAR mediatype.macOS.action.postProcess.MIME If this is "1", it indicates that the post processor takes a MIME entity (with MIME headers) as input, rather than just a body part. mtype-macmime = "0" / "1" mediatype.macOS.action.edit.bin This contains the 4-octet MacOS creator code of an application which the user wishes to use when editing documents of this type. If NIL, then the application referenced by the creator code is used. mtype-macpost = 4OCTET mediatype.macOS.action.edit.name This contains the filename of the application whose creator code is stored in mediatype.macOS.edit.bin. This value MUST be UTF-8 and not in another MacOS script or character set. mtype-macpname = 1*UTF8-CHAR mediatype.macOS.action.edit.MIME If this is "1", it indicates that the editor takes a MIME entity (with MIME headers) as input, rather than just a body part. mtype-macemime = "0" / "1" Newman & Melnikov Expires June 24, 2003 [Page 8] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.macOS.action.edit.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when launching the application referenced by the mediatype.macOS.action.edit attribute. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-maccsuppress = "0" / "1" mediatype.macOS.action.edit.alwaysUseHelper If this is "1", it states a user preference to use the specified helper application rather than any internal viewer contained in the dispatching application. mtype-macalways = "0" / "1" mediatype.macOS.stripResource If this is "1", it indicates a preference to strip the resource fork from this media type prior to transmission. mtype-macstripres = "0" / "1" 4.4 Unix Attributes These attributes are used to launch Unix helper applications similar to the mailcap [8] mechanism. When a client executes a Unix command line helper it runs under the Bourne shell (usually by using the system() function call). Prior to execution, the client SHOULD perform the following substitutions into the command line: the string "%s" is replaced by a temporary file name for the body part or MIME part (if %s is absent, the body part or MIME part is passed through standard input). The string "%t" is replaced by the media type and subtype, the string "%{}" is replaced by the media type parameter with name . The character "%" is quoted with "\%". By default, multi-part types are left intact with MIME headers prior to dispatching. A dispatching application MAY support the %n and %F options of mailcap [8] for backwards compatibility. mediatype.unix.action.view This contains a command to execute a viewer for the media type. mtype-unixview = *UTF8-CHAR Newman & Melnikov Expires June 24, 2003 [Page 9] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.unix.action.view.MIME If this is non-NIL it indicates that the viewer uses MIME entities (with complete headers) rather than body parts. mtype-unixvmime = "0" / "1" mediatype.unix.action.view.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when launching the viewer. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-unixvsuppress = "0" / "1" mediatype.unix.action.view.output This indicates any output assistance which the viewer command needs. The "terminal" option indicates an interactive terminal is needed and the dispatcher should create a terminal window or the equivalent. The "pager" option indicates the output may be more than 24 lines and the viewer does not have a built-in pager. mtype-unixout = "terminal" / "pager" mediatype.unix.action.compose This contains a command to execute a program to compose a new body part of the specified media type. If not set, it is assumed to be the same as mediatype.unix.editor. mtype-unixcomp = *UTF8-CHAR mediatype.unix.action.compose.MIME If this is non-NIL it indicates that the composer uses MIME entities (with complete headers) rather than body parts. mtype-unixcmime = "0" / "1" mediatype.unix.action.edit This contains a command to execute a program to edit body parts of the specified media type. If not set, it is assumed to be the same as mediatype.unix.view. mtype-unixedit = *UTF8-CHAR Newman & Melnikov Expires June 24, 2003 [Page 10] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.unix.action.edit.MIME If this is non-NIL it indicates that the editor uses MIME entities (with complete headers) rather than body parts. mtype-unixemime = "0" / "1" mediatype.unix.action.edit.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when launching the viewer. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-unixesuppress = "0" / "1" mediatype.unix.action.print This contains a command to print a body part of the specified type. mtype-unixprint = *UTF8-CHAR mediatype.unix.action.print.MIME If this is non-NIL it indicates that the print command uses MIME entities (with complete headers) rather than body parts. mtype-unixpmime = "0" / "1" mediatype.unix.action.print.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when launching the viewer. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-unixpsuppress = "0" / "1" mediatype.unix.alwaysUseHelper If this is non-NIL, it states a user preference to use the specified helper application rather than any internal viewer contained in the dispatching application. mtype-unixalways = "0" / "1" Newman & Melnikov Expires June 24, 2003 [Page 11] Internet-Draft ACAP Media Type Dataset Class December 2002 4.5 Microsoft Windows Attributes These attributes are used to launch Windows helper applications. Prior to execution of the action attributes, the client MUST perform the following substitutions into the command line: The strings "%r" and "%p" are replaced by the Windows System Directory and the Program Files Directory respectively (The Program Files Directory name can be obtained from the registry key "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion" attribute "ProgramFilesDir"). The string "%s" is replaced by a temporary file name for the body part or MIME part (if %s is absent, the body part or MIME part is passed through standard input). The string "%t" is replaced by the media type and subtype, the string "%{}" is replaced by the media type parameter with name . The character "%" is quoted with "\%". By default, multi-part types are left intact with MIME headers prior to dispatching. In order to simplify configuration of multiple PCs %r and %p are used instead of explicit directory names, because different PCs may store the Windows System Directory on different drives. For example it is better to use "%r\system32\notepad.exe" instead of "E:\WinNT\system32\notepad.exe", where %r is equal to "E:\WinNT" on a specific PC. mediatype.win32.action.view This contains a command to execute a viewer for the media type. mtype-win32view = *UTF8-CHAR mediatype.win32.action.view.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when launching the viewer. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-win32vsuppress = "0" / "1" Newman & Melnikov Expires June 24, 2003 [Page 12] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.win32.action.view.MIME If this is "1" then it indicates that the viewer uses MIME entities (with complete headers) rather than body parts. mtype-win32vmime = "0" / "1" mediatype.win32.action.compose This contains a command to execute a program to compose a new body part of the specified media type. If not set, it is assumed to be the same as mediatype.win32.action.edit. mtype-win32comp = *UTF8-CHAR mediatype.win32.action.compose.MIME This contains a command to execute a program to compose a new body part of the specified media type. If not set, it is assumed to be the same as mediatype.win32.editor. mtype-win32cmime = "0" / "1" mediatype.win32.action.edit This contains a command to execute a program to edit body parts of the specified media type. If not set, it is assumed to be the same as mediatype.win32.action.view. mtype-win32edit = *UTF8-CHAR mediatype.win32.action.edit.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when editing the media type. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-win32editSup = "0" / "1" mediatype.win32.action.edit.MIME If this is "1" then the data will be sent as a MIME entity (including the MIME headers) rather than as just the body part. mtype-win32editMIME = "0" / "1" Newman & Melnikov Expires June 24, 2003 [Page 13] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.win32.action.print This contains a command to print a body part of the specified media type. mtype-win32print = *UTF8-CHAR mediatype.win32.action.print.suppressWarning If this is "1", it indicates a preference to suppress any security warnings for this media type when printing the media type. Values other than "1" SHOULD be treated as equivalent to NIL. mtype-win32printSup = "0" / "1" mediatype.win32.action.print.MIME If this is "1" then the data will be sent as a MIME entity (including the MIME headers) rather than as just the body part. mtype-win32printMIME = "0" / "1" mediatype.win32.alwaysUseHelper If this is non-NIL, it states a user preference to use the specified helper application rather than any internal viewer contained in the dispatching application. mtype-win32always = "0" / "1" mediatype.win32.icon If this is non-NIL, it contains a path and index to an icon representing the media type. An ACAP client MAY use local information in preference to this attribute. mtype-win32icon = *UTF8-CHAR "," number ; file name and zero based index of icon in this file Newman & Melnikov Expires June 24, 2003 [Page 14] Internet-Draft ACAP Media Type Dataset Class December 2002 4.5.1 Mapping MediaTypes to Windows Registry Many of the attributes in this dataset class correspond closely to attributes in the Windows registry. The following list describes how this mapping aligns. entry: Key HKEY_CLASSES_ROOT\ Attribute "" mediatype.common.type: Key HKEY_CLASSES_ROOT\ Attribute "Content Type" mediatype.common.description Key HKEY_CLASSES_ROOT\ Attribute "" mediatype.win32.action.view: Key HKEY_CLASSES_ROOT\\shell\open\command Attribute "" mediatype.win32.action.compose: Key HKEY_CLASSES_ROOT\\shell\new\command Attribute "" mediatype.win32.action.edit: Key HKEY_CLASSES_ROOT\\shell\edit\command Attribute "" mediatype.win32.action.print: Key HKEY_CLASSES_ROOT\\shell\print\command Attribute "" mediatype.win32.icon: Key HKEY_CLASSES_ROOT\\DefaultIcon Attribute "" mediatype.common.extension: Key HKEY_CLASSES_ROOT\MIME\Database\ Content Type\ Attribute "Extension" Where is a file extension (with leading dot), and is the value of the key HKEY_CLASSES_ROOT\, attribute "". 5. Usage Procedures In order to locate the entry to use with a MIME entity, the following procedure is taken; stopping whenever a single entry remains in the list after a step. 1. If the media type is application/octet-stream and there is a filename with extension present, search for entries with a matching extension or extensionOther field and skip to step 5. Newman & Melnikov Expires June 24, 2003 [Page 15] Internet-Draft ACAP Media Type Dataset Class December 2002 2. Search for entries with a mediatype.common.type of "/ ". Exclude any entries where the parameter on the media type doesn't match the parameters in mediatype.common.param.* attributes. For example, a "text/plain; charset=iso-2022-jp" media type does not match an entry with a "mediatype.common.param.charset" value of "utf-8". 3. If no matching entries result, look for a mediatype.common.type of "/*" and repeat step 1. 4. If there is a filename with extension present, use the extension to reduce the number of matches. 5. If any entry has a mediatype.common.preferred value other than "0", then exclude all entries with a mediatype.common.preferred value of "0". 6. If any entry has a mediatype.common.preferred attribute of "1" exclude all entries which have a NIL mediatype.common.preferred attribute. 7. If multiple matching entries remain, pick one at random or prompt the user. When launching the appropriate helper application, a security warning SHOULD be issued if the MIME entity arrived from an external source and the appropriate suppressWarning attribute is not "1". A security warning MAY be issued under any circumstances. Newman & Melnikov Expires June 24, 2003 [Page 16] Internet-Draft ACAP Media Type Dataset Class December 2002 6. Examples Here is an example mediatype entry. Multi-valued attributes are represented with parenthesis around the multiple values. attribute value --------- ----- entry JPEG image mediatype.common.type image/jpeg mediatype.common.extension jpg mediatype.common.extensionOther (jpeg jpe jfif jfi) mediatype.common.description JPEG is an image format most suitable for compressing photographs mediatype.common.suppressWarning 1 mediatype.macOS.type.bin JPEG mediatype.macOS.creator.bin JVWR mediatype.macOS.creator.name JPEG View mediatype.macOS.action.edit.bin 8BIM mediatype.macOS.action.edit.name Adobe Photoshop mediatype.unix.action.view xv Here is an example use of ACAP to fetch information about a media type by name: C: A047 SEARCH "/mediatype/~/default/" RETURN ("*") EQUAL "entry" "i;octet" "WinZip File" S: A047 ENTRY "WinZip File" (("modtime" "19980309102226") ("mediatype.common.extension" ("zip")) ("mediatype.common.type" ("application/x-zip-compressed")) ("mediatype.common.description" ("Zip archive file") ("mediatype.common.textualNewlines" "0") ("mediatype.win32.action.view" "%r\WinZip\winzip32.exe") ("mediatype.win32.icon" "%r\WinZip\winzip32.exe,0") ("mediatype.win32.alwaysUseHelper" "1")) S: A047 MODTIME "19980309105258" S: A047 OK "SEARCH completed" 7. Security Considerations This dataset provides the ability to identify a helper application to process a media type. Such helper applications may be subject to serious security considerations related to active content as discussed in MIME [2]. It is expected that programs which launch helper applications will display a security warning to the user unless the media type is known to be safe or the appropriate suppressWarning attribute is set. Newman & Melnikov Expires June 24, 2003 [Page 17] Internet-Draft ACAP Media Type Dataset Class December 2002 The suppressWarning attributes express security policy. The Unix and win32 action attributes are extremely security sensitive as they contain active content. These attributes are subject to a variety of active attacks. The CRAM-MD5 [12] authentication mechanism used by ACAP is inadequate both because it fails to authenticate the server and fails to provide integrity protection. This dataset class SHOULD only be used with a security layer such as STARTTLS [13] or DIGEST-MD5 [14]. 8. IANA Considerations This document constitutes the registration for the "mediatype" dataset class per section 7.3 of [6]. Dataset class name/attribute prefix: mediatype Purpose: Media Type Mappings Published Specification(s): This specification Person and email address to contact for further information: See Authors' Addresses section of this specification. Normative References [1] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, November 1996. [2] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, November 1996. [3] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [4] Freed, N. and K. Moore, "MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations", RFC 2231, November 1997. [5] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. [6] Newman, C. and J. Myers, "ACAP -- Application Configuration Access Protocol", RFC 2244, November 1997. [7] Yergeau, F., "UTF-8, a transformation format of ISO 10646", RFC Newman & Melnikov Expires June 24, 2003 [Page 18] Internet-Draft ACAP Media Type Dataset Class December 2002 2279, January 1998. Informative References [8] Borenstein, N., "A User Agent Configuration Mechanism For Multimedia Mail Format Information", RFC 1524, September 1993. [9] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996. [10] Hovey, R. and S. Bradner, "The Organizations Involved in the IETF Standards Process", BCP 11, RFC 2028, October 1996. [11] Freed, N., Klensin, J. and J. Postel, "Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures", BCP 13, RFC 2048, November 1996. [12] Klensin, J., Catoe, R. and P. Krumviede, "IMAP/POP AUTHorize Extension for Simple Challenge/Response", RFC 2195, September 1997. [13] Newman, C., "Using TLS with IMAP, POP3 and ACAP", RFC 2595, June 1999. [14] Leach, P. and C. Newman, "Using Digest Authentication as a SASL Mechanism", RFC 2831, May 2000. Authors' Addresses Chris Newman Sun Microsystems 1050 Lakes Drive West Covina, CA 91790 US EMail: chris.newman@sun.com Alexey Melnikov ACI Worldwide/MessagingDirect 59 Clarendon Road Watford, Hertfordshire WD17 1FQ United Kingdom Phone: +44 1923 81 2877 EMail: mel@messagingdirect.com Newman & Melnikov Expires June 24, 2003 [Page 19] Internet-Draft ACAP Media Type Dataset Class December 2002 Index E entry 4 M mediatype.common.description 6 mediatype.common.extension 5 mediatype.common.extensionOther 5 mediatype.common.magicNumber.bin 5 mediatype.common.MIME 6 mediatype.common.param. 5 mediatype.common.preferred 6 mediatype.common.suppressWarning 6 mediatype.common.textualNewlines 6 mediatype.common.type 4 mediatype.macOS.action.edit.alwaysUseHelper 9 mediatype.macOS.action.edit.bin 8 mediatype.macOS.action.edit.MIME 8 mediatype.macOS.action.edit.name 8 mediatype.macOS.action.edit.suppressWarning 9 mediatype.macOS.action.postProcess.bin 7 mediatype.macOS.action.postProcess.MIME 8 mediatype.macOS.action.postProcess.name 8 mediatype.macOS.creator.bin 7 mediatype.macOS.creator.name 7 mediatype.macOS.creator.suppressWarning 7 mediatype.macOS.stripResource 9 mediatype.macOS.type.bin 7 mediatype.unix.action.compose 10 mediatype.unix.action.compose.MIME 10 mediatype.unix.action.edit 10 mediatype.unix.action.edit.MIME 11 mediatype.unix.action.edit.suppressWarning 11 mediatype.unix.action.print 11 mediatype.unix.action.print.MIME 11 mediatype.unix.action.print.suppressWarning 11 mediatype.unix.action.view 9 mediatype.unix.action.view.MIME 10 mediatype.unix.action.view.output 10 mediatype.unix.action.view.suppressWarning 10 mediatype.unix.alwaysUseHelper 11 mediatype.win32.action.compose 13 mediatype.win32.action.compose.MIME 13 mediatype.win32.action.edit 13 mediatype.win32.action.edit.MIME 13 mediatype.win32.action.edit.suppressWarning 13 mediatype.win32.action.print 13 Newman & Melnikov Expires June 24, 2003 [Page 20] Internet-Draft ACAP Media Type Dataset Class December 2002 mediatype.win32.action.print.MIME 14 mediatype.win32.action.print.suppressWarning 14 mediatype.win32.action.view 12 mediatype.win32.action.view.MIME 12 mediatype.win32.action.view.suppressWarning 12 mediatype.win32.alwaysUseHelper 14 mediatype.win32.icon 14 Newman & Melnikov Expires June 24, 2003 [Page 21] Internet-Draft ACAP Media Type Dataset Class December 2002 Intellectual Property Statement The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. 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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 Newman & Melnikov Expires June 24, 2003 [Page 22] Internet-Draft ACAP Media Type Dataset Class December 2002 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. Newman & Melnikov Expires June 24, 2003 [Page 23]