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NETWORK WORKING GROUP                                        N. Williams
Internet-Draft                                          Cryptonector LLC
Intended status: Standards Track                             A. Melnikov
Expires: October 1, 2017                                       Isode Ltd
                                                          March 30, 2017


     Namespace Considerations and Registries for GSS-API Extensions
            draft-ietf-kitten-gssapi-extensions-iana-11.txt

Abstract

   This document describes the ways in which the GSS-API may be extended
   and directs the creation of an IANA registry for various GSS-API
   namespaces.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   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."

   This Internet-Draft will expire on October 1, 2017.

Copyright Notice

   Copyright (c) 2017 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.




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Table of Contents

   1.  Conventions used in this document . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   3.  Extensions to the GSS-API . . . . . . . . . . . . . . . . . .   2
   4.  Generic GSS-API Namespaces  . . . . . . . . . . . . . . . . .   3
   5.  Language Binding-Specific GSS-API Namespaces  . . . . . . . .   3
   6.  Extension-Specific GSS-API Namespaces . . . . . . . . . . . .   4
   7.  Registration Form . . . . . . . . . . . . . . . . . . . . . .   4
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   6
   8.1.  Initial Namespace Registrations . . . . . . . . . . . . . .   7
   8.1.1.  Example registrations . . . . . . . . . . . . . . . . . .   7
   8.2.  Registration Maintenance Guidelines . . . . . . . . . . . .   9
   8.2.1.  Sub-Namespace Symbol Pattern Matching . . . . . . . . . .  10
   8.2.2.  Expert Reviews of       Individual Submissions  . . . . .  10
   8.2.3.  Change Control  . . . . . . . . . . . . . . . . . . . . .  11
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  12
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  12
   10.1.  Normative References . . . . . . . . . . . . . . . . . . .  12
   10.2.  Informative References . . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

2.  Introduction

   There is a need for private-use and mechanism-specific extensions to
   the Generic Security Services Application Programming Interface (GSS-
   API).  As such extensions are designed and standardized (or not),
   both at the IETF and elsewhere, there is a non-trivial risk of
   namespace pollution and conflicts.  To avoid this we set out
   guidelines for extending the GSS-API and direct the creation of an
   IANA registry for GSS-API namespaces.

   Registrations of individual items and sub-namespaces are allowed.
   Each sub-namespace may provide different rules for registration,
   e.g., for mechanism-specific and private-use extensions.

3.  Extensions to the GSS-API

   Extensions to the GSS-API can be categorized as follows:

   o  Abstract API extensions




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   o  Implementation-specific

   o  Mechanism-specific

   o  Language binding-specific

   Extensions to the GSS-API may be purely semantic, without effect on
   the GSS-API's namespaces.  Or they may introduce new functions,
   constants, types, etc...; these clearly affect the GSS-API
   namespaces.

   Extensions that affect the GSS-API namespaces should be registered
   with the IANA as described herein.

4.  Generic GSS-API Namespaces

   The abstract API namespaces for the GSS-API are:

   o  Type names

   o  Function names

   o  Constant names for various types

   o  Constant values for various types

   o  Name types (OID, type name and syntaxes)

   Additionally we have namespaces associates with the OBJECT IDENTIFIER
   (OID) type.  The IANA already maintains a registry of such OIDs:

   o  Mechanism OIDs

   o  Name Type OIDs

5.  Language Binding-Specific GSS-API Namespaces

   Language binding specific namespaces include, among others:

   o  Header/interface module names

   o  Object classes and/or types

   o  Methods and/or functions

   o  Constant names

   o  Constant values



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6.  Extension-Specific GSS-API Namespaces

   Extensions to the GSS-API may create additional namespaces.  See
   Section 8.2.

7.  Registration Form

   Registrations for GSS-API namespaces SHALL take the following form:

   +--------------+---------------------+------------------------------+
   | Registration | Possible Values     | Description                  |
   | Field        |                     |                              |
   +--------------+---------------------+------------------------------+
   | Bindings     | 'Generic',          | Indicates the name of the    |
   |              | 'C-bindings',       | programming language that    |
   |              | 'Java', 'C#',       | this registration involves,  |
   |              | <programming        | or, if 'Generic', that this  |
   |              | language name>      | is an entry for the generic  |
   |              |                     | abstract GSS-API (i.e., not  |
   |              |                     | specific to any programming  |
   |              |                     | language).                   |
   +--------------+---------------------+------------------------------+
   | Registration | 'Instance', 'Sub-   | Indicates whether this entry |
   | type         | Namespace'          | reserves a given symbol name |
   |              |                     | (and possibly, constant      |
   |              |                     | value), or whether it        |
   |              |                     | reserves an entire sub-      |
   |              |                     | namespace (the name is a     |
   |              |                     | pattern) or constant value   |
   |              |                     | range.                       |
   +--------------+---------------------+------------------------------+
   | Object Type  | <Symbol> defined by | Indicates the type of the    |
   |              | the binding         | object whose symbolic name   |
   |              | language (for       | or constant value this entry |
   |              | example 'Data-      | registers.  The possible     |
   |              | Type', 'Function',  | values of this field depend  |
   |              | 'Method',           | on the programming language  |
   |              | 'Integer',          | in question, therefore they  |
   |              | 'String', 'OID',    | are not all specified here.  |
   |              | 'Context-Flag',     |                              |
   |              | 'Name-Type',        |                              |
   |              | 'Macro', 'Header-   |                              |
   |              | File-Name',         |                              |
   |              | 'Module-Name',      |                              |
   |              | 'Class')            |                              |
   +--------------+---------------------+------------------------------+
   | Symbol       | <Symbol name or     | The name of a symbol or      |
   | Name/Prefix  | name pattern>       | symbol sub-namespace being   |



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   |              |                     | registered.  See Section     |
   |              |                     | 8.2.1                        |
   +--------------+---------------------+------------------------------+
   | Binding of   | <Name of abstract   | If the registration is for a |
   |              | API element of      | specific language binding of |
   |              | which this object   | the GSS-API, then this names |
   |              | is a binding>       | the abstract API element of  |
   |              |                     | which it is a binding        |
   |              |                     | (OPTIONAL).                  |
   +--------------+---------------------+------------------------------+
   | Constant     | <Constant value> or | The value of the constant    |
   | Value/Range  | <constant value     | named by the <Symbol         |
   |              | range>              | Name/Prefix>. This field is  |
   |              |                     | present only for Instance    |
   |              |                     | and Sub-namespace            |
   |              |                     | registrations of Constant    |
   |              |                     | object types.                |
   +--------------+---------------------+------------------------------+
   | Description  | <Text>              | Description of the           |
   |              |                     | registration.  Multiple      |
   |              |                     | instances of this field may  |
   |              |                     | result (see Section 8.2.3).  |
   +--------------+---------------------+------------------------------+
   | Registration | <Reference> to an   | Describes the rules for      |
   | Rules        | IANA registration   | allocation of items that     |
   |              | Policy defined in   | fall in this sub-namespace,  |
   |              | [RFC5226] (or an    | for entries with             |
   |              | RFC that updates    | Registration Type of Sub-    |
   |              | it), for instance   | namespace (OPTIONAL).  For   |
   |              | 'IESG Approval',    | private use sub-namespaces   |
   |              | 'Expert Review',    | the submitter MUST provide   |
   |              | 'First Come First   | the e-mail address of a      |
   |              | Served', 'Private   | responsible contact.  If     |
   |              | Use'.               | this field is not specified  |
   |              |                     | for a sub-namespace, the     |
   |              |                     | default registration rules   |
   |              |                     | specified in Section 8.2     |
   |              |                     | apply.                       |
   +--------------+---------------------+------------------------------+
   | Reference    | <Reference>         | Reference to a document that |
   |              |                     | describes the registration,  |
   |              |                     | if any (OPTIONAL).  Multiple |
   |              |                     | instances of this field are  |
   |              |                     | allowed, with one reference  |
   |              |                     | each.                        |
   +--------------+---------------------+------------------------------+
   | Expert       | <Name of expert     | OPTIONAL, see Section 8.2.2. |
   | Reviewer     | reviewers, possibly | Multiple instances of this   |



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   |              | WG names>           | field are allowed, with one  |
   |              |                     | expert reviewer per-         |
   |              |                     | instance.  Leave this field  |
   |              |                     | blank when requesting a      |
   |              |                     | registration.  It will be    |
   |              |                     | filled in by the Expert who  |
   |              |                     | reviews the registration.    |
   +--------------+---------------------+------------------------------+
   | Expert       | <Notes from the     | Expert reviewers may request |
   | Review Notes | expert review>      | that some comments be        |
   |              |                     | included with the            |
   |              |                     | registration, e.g.,          |
   |              |                     | regarding security           |
   |              |                     | considerations of the        |
   |              |                     | registered extension.        |
   +--------------+---------------------+------------------------------+
   | Status       | 'Registered' or     | Status of the registration.  |
   |              | 'Obsoleted'         |                              |
   +--------------+---------------------+------------------------------+
   | Obsoleting   | <Reference>         | Reference to a document, if  |
   | Reference    |                     | any, that obsoletes this     |
   |              |                     | registration.  Multiple      |
   |              |                     | instances of this field are  |
   |              |                     | allowed, with one reference  |
   |              |                     | each.  (OPTIONAL)            |
   +--------------+---------------------+------------------------------+

   The IANA should create a single GSS-API namespace registry, or
   multiple registries, one for symbolic names and one for constant
   values, and/or it may create a registry per-programming language, at
   its convenience.

   Entries in these registries should consist of all the fields from
   their corresponding registration entries.

   Entries should be sorted by: programming language, registration type,
   object type, and symbol name/pattern.

8.  IANA Considerations

   This document deals with IANA considerations throughout.
   Specifically it creates a single registry of various kinds of things,
   though the IANA may instead create multiple registries, each for one
   of those kinds of things.  Of particular interest may be that IANA
   will now be the registration authority for the GSS-API name type OID
   space.





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8.1.  Initial Namespace Registrations

   Initial registry content corresponding to the items defined in
   [RFC2743], [RFC2744], [RFC2853], [RFC1964] and [RFC4121] and others
   will be supplied during the IANA review portion of the RFC publishing
   process.  [[Note to RFC Editor: Delete the following sentence before
   publication:]] The KITTEN WG chairs MUST indicate that such content
   has been reviewed by the WG and that there is WG consensus that the
   entries are in agreement with those RFCs.

8.1.1.  Example registrations

   In order to sanity check recommended IANA registration templates,
   this section registers several entries.

   +--------------------+----------------------------------------------+
   | Registration Field | Possible Values                              |
   +--------------------+----------------------------------------------+
   | Bindings           | C-bindings                                   |
   +--------------------+----------------------------------------------+
   | Registration type  | Instance                                     |
   +--------------------+----------------------------------------------+
   | Object Type        | Function                                     |
   +--------------------+----------------------------------------------+
   | Symbol Name        | gss_init_sec_context                         |
   +--------------------+----------------------------------------------+
   | Binding of         | GSS_Init_sec_context                         |
   +--------------------+----------------------------------------------+
   | Constant           | N/A                                          |
   | Value/Range        |                                              |
   +--------------------+----------------------------------------------+
   | Description        | Create a security context by initiator       |
   +--------------------+----------------------------------------------+
   | Registration Rules | N/A                                          |
   +--------------------+----------------------------------------------+
   | Reference          | RFC 2744                                     |
   +--------------------+----------------------------------------------+
   | Expert Reviewer    | Kitten WG                                    |
   +--------------------+----------------------------------------------+
   | Expert Review      |                                              |
   | Notes              |                                              |
   +--------------------+----------------------------------------------+
   | Status             | Registered                                   |
   +--------------------+----------------------------------------------+
   | Obsoleting         | N/A                                          |
   | Reference          |                                              |
   +--------------------+----------------------------------------------+




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   +--------------------+----------------------------------------------+
   | Registration Field | Possible Values                              |
   +--------------------+----------------------------------------------+
   | Bindings           | C-bindings                                   |
   +--------------------+----------------------------------------------+
   | Registration type  | Instance                                     |
   +--------------------+----------------------------------------------+
   | Object Type        | Function                                     |
   +--------------------+----------------------------------------------+
   | Symbol Name        | gss_accept_sec_context                       |
   +--------------------+----------------------------------------------+
   | Binding of         | GSS_Accept_sec_context                       |
   +--------------------+----------------------------------------------+
   | Constant           | N/A                                          |
   | Value/Range        |                                              |
   +--------------------+----------------------------------------------+
   | Description        | Accept a security context from initiator     |
   +--------------------+----------------------------------------------+
   | Registration Rules | N/A                                          |
   +--------------------+----------------------------------------------+
   | Reference          | RFC 2744                                     |
   +--------------------+----------------------------------------------+
   | Expert Reviewer    | Kitten WG                                    |
   +--------------------+----------------------------------------------+
   | Expert Review      |                                              |
   | Notes              |                                              |
   +--------------------+----------------------------------------------+
   | Status             | Registered                                   |
   +--------------------+----------------------------------------------+
   | Obsoleting         | N/A                                          |
   | Reference          |                                              |
   +--------------------+----------------------------------------------+



















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   +--------------------+----------------------------------------------+
   | Registration Field | Possible Values                              |
   +--------------------+----------------------------------------------+
   | Bindings           | C-bindings                                   |
   +--------------------+----------------------------------------------+
   | Registration type  | Instance                                     |
   +--------------------+----------------------------------------------+
   | Object Type        | Context-Flag                                 |
   +--------------------+----------------------------------------------+
   | Symbol Name        | GSS_C_DELEG_FLAG                             |
   +--------------------+----------------------------------------------+
   | Binding of         | deleg_state or deleg_req_flag                |
   +--------------------+----------------------------------------------+
   | Constant           | 1                                            |
   | Value/Range        |                                              |
   +--------------------+----------------------------------------------+
   | Description        | On output (if set): Delegated credentials    |
   |                    | are available via the delegated_cred_handle  |
   |                    | parameter of GSS_Accept_sec_context.  On     |
   |                    | input (if set): With the call to             |
   |                    | GSS_Init_sec_context, delegate credentials   |
   |                    | to the acceptor.                             |
   +--------------------+----------------------------------------------+
   | Registration Rules | N/A                                          |
   +--------------------+----------------------------------------------+
   | Reference          | RFC 2744                                     |
   +--------------------+----------------------------------------------+
   | Expert Reviewer    | Kitten WG                                    |
   +--------------------+----------------------------------------------+
   | Expert Review      |                                              |
   | Notes              |                                              |
   +--------------------+----------------------------------------------+
   | Status             | Registered                                   |
   +--------------------+----------------------------------------------+
   | Obsoleting         | N/A                                          |
   | Reference          |                                              |
   +--------------------+----------------------------------------------+

8.2.  Registration Maintenance Guidelines

   Standards-Track RFCs can create new items with any non-conflicting
   Symbol Name/Prefix value for this registry by virtue of IESG approval
   to publish as a Standards-Track RFC -- that is, without additional
   expert review.

   Standards-Track RFCs can mark existing entries as obsolete, and can
   even create conflicting entries if explicitly stated (the IESG, of
   course, should review conflicts carefully, and may reject them).



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   IANA shall also consider submissions from individuals, and via
   Informational and Experimental RFCs, subject to Expert Review.  IANA
   SHALL allow such registrations if a) they are not conflicting, b)
   provided that the registration is for object types other than
   Context-Flags, and c) subject to expert review.  Guidelines for
   expert reviews are given below.

8.2.1.  Sub-Namespace Symbol Pattern Matching

   Sub-namespace registrations must provide a pattern for matching
   symbols for which the sub-namespace's registration rules apply.  The
   pattern consists of a string with the following special tokens:

   o  '*', meaning "match any string."

   o  "%m", meaning "match any mechanism family short-hand name."

   o  "%i", meaning "match any implementor vanity short-hand name."

   For example, "GSS_%m_*" matches "GSS_krb5_foo" since "krb5" is a
   common short-hand for the Kerberos V GSS-API mechanism [RFC1964].
   But "GSS_%m_*" does not match "GSS_foo_bar" unless "foo" is asserted
   to be a short-hand for some mechanism.

8.2.2.  Expert Reviews of Individual Submissions

   [[The following paragraph should be deleted from the document before
   publication, as it will not age well.  It should be moved to the
   shepherding write-up.]]

   Expert review selection SHALL be done as follows.  If, at the time
   that the IANA receives an individual submission for registration in
   this registry, there are any IETF Working Groups chartered to produce
   GSS-API-related documents, then the IANA SHALL ask the chairs of such
   WGs to be expert reviewers or to name one.  If there are no such WGs
   at that time, then the IANA SHALL ask past chairs of the KITTEN WG
   and the author/editor of this RFC to act as expert reviewers or name
   an alternate.

   Expert reviewers of individual registration submissions with
   Registration Type == Sub-namespace should check that the registration
   request has a suitable description (which doesn't need to be
   sufficiently detailed for others to implement) and that the Symbol
   Name/Prefix is sufficiently descriptive of the purpose of the sub-
   namespace or reflective of the name of the submitter or associated
   company.

   Expert reviewers of individual registration submissions with



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   Registration Type == Instance should check that the Symbol Name falls
   under a sub-namespace controlled by the submitter.  Registration of
   such entries which do not fall under such a sub-namespace may be
   allowed provided that they correspond to long existing non-standard
   extensions to the GSS-API and this can be easily checked or
   demonstrated, otherwise IESG Protocol Action is REQUIRED (see
   previous section).  Also, reviewers should check that any
   registration of constant values have a detailed description that is
   suitable for other implementors to reproduce, and that they don't
   conflict with other usages or are otherwise dangerous in the
   reviewers estimation.

   Expert reviewers should review impact on mechanisms, security and
   interoperability, and may reject or annotate registrations which can
   have mechanism impact that requires IESG protocol action.  Consider,
   for example, new versions of GSS_Init_sec_context() and/or
   GSS_Accept_sec_context which have new input and/or output parameters
   which imply changes on the wire or in behaviour that may result in
   interoperability issues.  A reviewer could choose to add notes to the
   registration describing such issues, or the reviewer might conclude
   that the danger to Internet interoperability is sufficient to warrant
   rejecting the registration.

8.2.3.  Change Control

   Registered entries may be marked obsoleted using the same expert
   review process as for registering new entries.  Obsoleted entries are
   not, however, to be deleted, but merely marked having Obsoleted
   Status.  Note that entries may be created as obsoleted to record the
   fact that the given symbol(s) have been used before, even though
   continued use of them is discouraged.

   Registered entries may also be updated in two other ways: additional
   references, obsoleting references, and descriptions may be added.

   All changes are subject to expert review, except for changes to
   registrations in a sub-namespace which are subject to the rules of
   the relevant sub-namespace.  The submitter of a change request need
   not be the same as the original submitter.

   Registrations may be modified by addition, but under no circumstance
   may any fields be modified except for the Status field or Contact
   Address, or to correct for transcription errors in filing or
   processing registration requests.

   The IANA SHALL add a field describing the date that a an addition or
   modification was made, and a description of the change.




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9.  Security Considerations

   General security considerations relating to IANA registration
   services apply; see [RFC5226].

   Also, expert reviewers should look for and may document security
   related issues with submitters' GSS-API extensions, to the best of
   the reviewers' ability given the information furnished by the
   submitter.  Reviewers may add comments regarding their limited
   ability to review a submission for security problems if the submitter
   is unwilling to provide sufficient documentation.

10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC2743]  Linn, J., "Generic Security Service Application Program
              Interface Version 2, Update 1", RFC 2743,
              DOI 10.17487/RFC2743, January 2000,
              <http://www.rfc-editor.org/info/rfc2743>.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              DOI 10.17487/RFC5226, May 2008,
              <http://www.rfc-editor.org/info/rfc5226>.

10.2.  Informative References

   [RFC1964]  Linn, J., "The Kerberos Version 5 GSS-API Mechanism",
              RFC 1964, DOI 10.17487/RFC1964, June 1996,
              <http://www.rfc-editor.org/info/rfc1964>.

   [RFC2744]  Wray, J., "Generic Security Service API Version 2 :
              C-bindings", RFC 2744, DOI 10.17487/RFC2744, January 2000,
              <http://www.rfc-editor.org/info/rfc2744>.

   [RFC2853]  Kabat, J. and M. Upadhyay, "Generic Security Service API
              Version 2 : Java Bindings", RFC 2853,
              DOI 10.17487/RFC2853, June 2000,
              <http://www.rfc-editor.org/info/rfc2853>.






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   [RFC4121]  Zhu, L., Jaganathan, K., and S. Hartman, "The Kerberos
              Version 5 Generic Security Service Application Program
              Interface (GSS-API) Mechanism: Version 2", RFC 4121,
              DOI 10.17487/RFC4121, July 2005,
              <http://www.rfc-editor.org/info/rfc4121>.

Authors' Addresses

   Nicolas      Williams
   Cryptonector LLC

   Email: nico@cryptonector.com


   Alexey Melnikov
   Isode Ltd
   5 Castle Business Village
   36 Station Road
   Hampton, Middlesex  TW12 2BX
   UK

   Email: Alexey.Melnikov@isode.com





























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