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Data Types in RADIUS
draft-ietf-radext-datatypes-08

The information below is for an old version of the document that is already published as an RFC.
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This is an older version of an Internet-Draft that was ultimately published as RFC 8044.
Author Alan DeKok
Last updated 2017-01-25 (Latest revision 2016-10-18)
Replaces draft-dekok-radext-datatypes
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Document shepherd Stefan Winter
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draft-ietf-radext-datatypes-08
Network Working Group                                        DeKok, Alan
INTERNET-DRAFT                                                FreeRADIUS
Updates: 2865,3162,6158,6572
Category: Standards Track
<draft-ietf-radext-datatypes-08.txt>
18 October 2016

                Data Types in the Remote Authentication
                 Dial-In User Service Protocol (RADIUS)

Abstract

   RADIUS specifications have used data types for two decades without
   defining them as managed entities.  During this time, RADIUS
   implementations have named the data types, and have used them in
   attribute definitions.  This document updates the specifications to
   better follow established practice.  We do this by naming the data
   types defined in RFC 6158, which have been used since at least the
   publication of RFC 2865.  We provide an IANA registry for the data
   types, and update the RADIUS Attribute Type registry to include a
   "Data Type" field for each attribute.  Finally, we recommend that
   authors of RADIUS specifications use these types in preference to
   existing practice.  This document updates RFC 2865, 3162, 6158, and
   6572.

Status of this Memo

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

   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 May 18, 2017.

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Copyright Notice

   Copyright (c) 2016 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.  Introduction .............................................    4
   1.1.  Specification Problems with Data Types ..............    4
   1.2.  Implementation Problems with Data Types .............    5
   1.3.  No Mandated Changes .................................    5
   1.4.  Requirements Language ...............................    5
2.  Use of Data Types ........................................    6
   2.1.  Specification Use of Data Types .....................    6
      2.1.1.  Field Names for Attribute Values ...............    6
      2.1.2.  Attribute Definitions using Data Types .........    7
      2.1.3.  Format of Attribute Definitions ................    7
      2.1.4.  Defining a New Data Type .......................    8
   2.2.  Implementation Use of Data Types ....................    9
3.  Data Type Definitions ....................................   11
   3.1.  integer .............................................   12
   3.2.  enum ................................................   12
   3.3.  time ................................................   13
   3.4.  text ................................................   13
   3.5.  string ..............................................   14
   3.6.  concat ..............................................   16
   3.7.  ifid ................................................   16
   3.8.  ipv4addr ............................................   17
   3.9.  ipv6addr ............................................   18
   3.10.  ipv6prefix .........................................   18
   3.11.  ipv4prefix .........................................   20
   3.12.  integer64 ..........................................   21
   3.13.  tlv ................................................   22
   3.14.  vsa ................................................   23
   3.15.  extended ...........................................   24
   3.16.  long-extended ......................................   26
   3.17.  evs ................................................   29
4.  Updated Registries .......................................   30
   4.1.  Create a Data Type Registry .........................   30
   4.2.  Updates to the Attribute Type Registry ..............   31
5.  Security Considerations ..................................   36
6.  IANA Considerations ......................................   37
7.  References ...............................................   37
   7.1.  Normative References ................................   37
   7.2.  Informative References ..............................   38

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1.  Introduction

   RADIUS specifications have historically defined attributes in terms
   of name, value, and data type.  Of these three pieces of information,
   the name is recorded by IANA in the RADIUS Attribute Type registry,
   but not otherwise managed or restricted, as discussed in [RFC6929]
   Section 2.7.1.  The value is managed by IANA, and recorded in that
   registry.  The data type is not managed or recorded in the RADIUS
   Attribute Type registry.  Experience has shown that there is a need
   to create well known data types, and have them managed by IANA.

   This document defines an IANA RADIUS Data Type registry, and updates
   the RADIUS Attribute Type registry to use those newly defined data
   types.  It recommends how both specifications and implementations
   should use the data types.  It extends the RADIUS Attribute Type
   registry to have a data type for each assigned attribute.

   In this section, we review the use of data types in specifications
   and implementations.  Whe highlight ambiguities and inconsistencies.
   The rest of this document is devoted to resolving those problems.

1.1.  Specification Problems with Data Types

   When attributes are defined in the specifications, the terms "Value"
   and "String" are used to refer to the contents of an attribute.
   However, these names are used recursively and inconsistently.  We
   suggest that defining a field to recursively contain itself is
   problematic.

   A number of data type names and definitions are given in [RFC2865]
   Section 5, at the bottom of page 25.  These data types are named and
   clearly defined.  However, this practice was not continued in later
   specifications.

   Specifically, [RFC2865] defines attributes of data type "address" to
   carry IPv4 addresses.  Despite this definition, [RFC3162] defines
   attributes of data type "Address" to carry IPv6 addresses.  We
   suggest that the use of the word "address" to refer to disparate data
   types is problematic.

   Other failures are that [RFC3162] does not give a data type name and
   definition for the data types IPv6 address, Interface-Id, or IPv6
   prefix.  [RFC2869] defines Event-Timestamp to carry a time, but does
   not re-use the "time" data type defined in [RFC2865].  Instead, it
   just repeats the "time" definition.  [RFC6572] defines multiple
   attributes which carry IPv4 prefixes.  However, an "IPv4 prefix" data
   type is not named, defined as a data type, or called out as an
   addition to RADIUS.  Further, [RFC6572] does not follow the

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   recommendations of [RFC6158], and does not explain why it fails to
   follow those recommendations.

   These ambiguities and inconsistencies need to be resolved.

1.2.  Implementation Problems with Data Types

   RADIUS implementations often use "dictionaries" to map attribute
   names to type values, and to define data types for each attribute.
   The data types in the dictionaries are defined by each
   implementation, but correspond to the "ad hoc" data types used in the
   specifications.

   In effect, implementations have seen the need for well-defined data
   types, and have created them.  It is time for RADIUS specifications
   to follow this practice.

1.3.  No Mandated Changes

   This document mandates no changes to any RADIUS implementation, past,
   present, or future.  It instead documents existing practice, in order
   to simplify the process of writing RADIUS specifications, to clarify
   the interpretation of RADIUS standards, and to improve the
   communication between specification authors and IANA.

   This document suggests that implementations SHOULD use the data types
   defined here, in preference to any "ad hoc" data types currently in
   use.  This suggestion should have minimal effect on implementations,
   as most "ad hoc" data types are compatible with the ones defined
   here.  Any difference will typically be limited to the name of the
   data type.

   This document updates [RFC6158] to permit the data types defined in
   the "Data Type registry" as "basic data types", as per Section 2.1 of
   that document.  The recommendations of [RFC6158] are otherwise
   unchanged.

1.4.  Requirements Language

   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].

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2.  Use of Data Types

   The Data Types can be used in two places: specifications, and
   implementations.  This section discusses both uses, and gives
   guidance on using the data types.

2.1.  Specification Use of Data Types

   In this section, we give recommendations for how specifications
   should be written using data types.  We first describe how attribute
   field names can be consistently named.  We then describe how
   attribute definitions should use the data types, and deprecate the
   use of "ASCII art" for attribute definitions.  We suggest a format
   for new attribute definitions.  This format includes recommended
   fields, and suggestions for how those fields should be described.

   Finally, we make recommendations for how new data types should be
   defined.

2.1.1.  Field Names for Attribute Values

   Previous specifications used inconsistent and conflicting names for
   the contents of RADIUS attributes.  For example, the term "Value" is
   used in [RFC2865] Section 5 to define a field which carries the
   contents of attribute.  It is then used in later sections as the sub-
   field of attribute contents.  The result is that the field is defined
   as recursively containing itself.  Similarly, "String" is used both
   as a data type, and as a sub-field of other data types.

   We correct this ambiguity by using context-specific names for various
   fields of attributes and data types.  It then becomes clear that, for
   example, that a field called "VSA-Data" must contain different data
   than a field called "EVS-Data".  Each new name is defined where it is
   used.

   We also define the following term:

      Attr-Data

         The "Value" field of an Attribute as defined in [RFC2865]
         Section 5.  The contents of this field MUST be of a valid data
         type as defined in the RADIUS Data Type registry.

   We consistently use "Attr-Data" to refer to the contents of an
   attribute, instead of the more ambiguous name "Value".  It is
   RECOMMENDED that new specifications follow this practice.

   We consistently use "Value" to refer to the contents of a data type,

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   where that data type is simple.  For example, an "integer" can have a
   "Value".  In contrast, a Vendor-Specific attribute carries complex
   information, and thus cannot have a "Value".

   For data types which carry complex information, we name the fields
   based on the data type.  For example, a Vendor-Specific attribute is
   defined to carry a "vsa" data type, and the contents of that data
   type are described herein as "VSA-Data".

   These terms are used in preference to the term "String", which was
   previously used in ambiguous ways.  It is RECOMMENDED that future
   specifications use type-specific names, and the same naming scheme
   for new types.  This use will maintain consistent definitions, and
   help to avoid ambiguities.

2.1.2.  Attribute Definitions using Data Types

   New RADIUS specifications MUST define attributes using data types
   from the RADIUS Data Type registry.  The specification may, of
   course, define a new data type update the "Data Types" registry, and
   use the new data type, all in the same document.  The guidelines
   given in [RFC6929] MUST be followed when defining a new data type.

   Attributes can usually be completely described via the Attribute Type
   value, name, and data type.  The use of "ASCII art" is then limited
   only to the definition of new data types, and for complex data types.

   Use of the new extended attributes [RFC6929] makes ASCII art even
   more problematic.  An attribute can be allocated from any of the
   extended spaces, with more than one option for attribute header
   format.  This allocation decision is made after the specification has
   been accepted for publication.  As the allocation affects the format
   of the attribute header, it is essentially impossible to create the
   correct ASCII art prior to final publication.  Allocation from the
   different spaces also changes the value of the Length field, also
   making it difficult to define it correctly prior to final publication
   of the document.

   It is therefore RECOMMENDED that "ASCII art" diagrams not be used for
   new RADIUS attribute specifications.

2.1.3.  Format of Attribute Definitions

   When defining a new attribute, the following fields SHOULD be given:

      Description

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         A description of the meaning and interpretation of the
         attribute.

      Type

         The Attribute Type value, given in the "dotted number" notation
         from [RFC6929].  Specifications can often leave this as "TBD",
         and request that IANA fill in the allocated values.

      Length

         A description of the length of the attribute.  For attributes
         of variable length, a maximum length SHOULD be given.  Since
         the Length may depend on the Type, the definition of Length may
         be affected by IANA allocations.

      Data Type

         One of the named data types from the RADIUS Data Type registry.

      Value

         A description of any attribute-specific limitations on the
         values carried by the specified data type.  If there are no
         attribute-specific limitations, then the description of this
         field can be omitted, so long as the Description field is
         sufficiently explanatory.

         Where the values are limited to a subset of the possible range,
         valid range(s) MUST be defined.

         For attributes of data type "enum", a list of enumerated values
         and names MUST be given, as with [RFC2865] Section 5.6.

   Using a consistent format for attribute definitions helps to make the
   definitions clearer.

2.1.4.  Defining a New Data Type

   When a specification needs to define a new data type, it SHOULD
   follow the format used by the definitions in Section 3 of this
   document.  The text at the start of the data type definition MUST
   describe the data type, including the expected use, and why a new
   data type is required.  That text SHOULD include limits on expected
   values, and why those limits exist.  The field's "Name", "Value",
   "Length", and "Format", MUST be given, along with values.

   The "Name" field SHOULD be a single name, all lower-case.

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   Contractions such as "ipv4addr" are RECOMMENDED where they add
   clarity.

   We note that the use of "Value" in the RADIUS Data Type registry can
   be confusing.  That name is also used in attribute definitions, but
   with a different meaning.  We trust that the meaning here is clear
   from the context.

   The "Value" field SHOULD be given as to be determined or "TBD" in
   specifications.  That number is assigned by IANA.

   The "Format" field SHOULD be defined with "ASCII art" in order to
   have a precise definition.  Machine-readable formats are also
   RECOMMENDED.

   The definition of a new data type should be done only when absolutely
   necessary.  We do not expect a need for a large number of new data
   types.  When defining a new data type, the guideliness of [RFC6929]
   with respect to data types MUST be followed.

   It is RECOMMENDED that vendors not define "vendor specific" data
   types.  As discussed in [RFC6929], those data types are rarely
   necessary, and can cause interoperability problems.

   Any new data type MUST have unique name in the RADIUS Data Type
   registry.  The number of the data type will be assigned by IANA.

2.2.  Implementation Use of Data Types

   Implementations not supporting a particular data type MUST treat
   attributes of that data type as being of data type "string", as
   defined in Section 3.6.  It is RECOMMENDED that such attributes be
   treated as "invalid attributes", as defined in [RFC6929] Section 2.8.

   Where the contents of a data type do not match the definition,
   implementations MUST treat the the enclosing attribute as being an
   "invalid attribute".  This requirement includes, but is not limited
   to, the following situations:

   * Attributes with values outside of the allowed range(s) for the
     data type, e.g. as given in the data types "integer", "ipv4addr",
     "ipv6addr", "ipv4prefix", "ipv6prefix", or "enum".

   * "text" attributes where the contents do not match the required
     format,

   * Attributes where the length is shorter or longer than the allowed
     length(s) for the given data type,

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   The requirements for "reserved" fields are more difficult to
   quantify.  Implementations SHOULD be able to receive and process
   attributes where "reserved" fields are non-zero.  We do not, however,
   define any "correct" processing of such attributes.  Instead,
   specifications which define new meaning for "reserved" fields SHOULD
   describe how the new meaning is compatible with older
   implementations.  We expect that such descriptions are derived from
   practice.  Implementations MUST set "reserved" fields to zero when
   creating attributes.

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3.  Data Type Definitions

   This section defines the new data types.  For each data type, it
   gives a definition, a name, a number, a length, and an encoding
   format.  Where relevant, it describes subfields contained within the
   data type.  These definitions have no impact on existing RADIUS
   implementations.  There is no requirement that implementations use
   these names.

   Where possible, the name of each data type has been taken from
   previous specifications.  In some cases, a different name has been
   chosen.  The change of name is sometimes required to avoid ambiguity
   (i.e. "address" versus "Address").  Otherwise, the new name has been
   chosen to be compatible with [RFC2865], or with use in common
   implementations.  In some cases, new names are chosen to clarify the
   interpretation of the data type.

   The numbers assigned herein for the data types have no meaning other
   than to permit them to be tracked by IANA.  As RADIUS does not encode
   information about data types in a packet, the numbers assigned to a
   data type will never occur in a packet.  It is RECOMMENDED that new
   implementations use the names defined in this document, in order to
   avoid confusion.  Existing implementations may choose to use the
   names defined here, but that is not required.

   The encoding of each data type is taken from previous specifications.
   The fields are transmitted from left to right.

   Where the data types have inter-dependencies, the simplest data type
   is given first, and dependent ones are given later.

   We do not create specific data types for the "tagged" attributes
   defined in [RFC2868].  That specification defines the "tagged"
   attributes as being backwards compatible with pre-existing data
   types.  In addition, [RFC6158] Section 2.1 says that "tagged"
   attributes should not be used.  There is therefore no benefit to
   defining additional data types for these attributes.  We trust that
   implementors will be aware that tagged attributes must be treated
   differently from non-tagged attributes of the same data type.

   Similarly, we do not create data types for some attributes having
   complex structure, such as CHAP-Password, ARAP-Features, or Location-
   Information.  We need to strike a balance between correcting earlier
   mistakes, and making this document more complex.  In some cases, it
   is better to treat complex attributes as being of type "string", even
   though they need to be interpreted by RADIUS implementations.  The
   guidelines given in Section 6.3 of [RFC6929] were used to make this
   determination.

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3.1.  integer

   The "integer" data type encodes a 32-bit unsigned integer in network
   byte order.  Where the range of values for a particular attribute is
   limited to a sub-set of the values, specifications MUST define the
   valid range.  Attributes with Values outside of the allowed ranges
   SHOULD be treated as "invalid attributes".

   Name

      integer

   Value

      1

   Length

      Four octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Value                                                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.2.  enum

   The "enum" data type encodes a 32-bit unsigned integer in network
   byte order.  It differs from the "integer" data type only in that it
   is used to define enumerated types, such as Service-Type (Section 5.6
   of [RFC2865]).  Specifications MUST define a valid set of enumerated
   values, along with a unique name for each value.  Attributes with
   Values outside of the allowed enumerations SHOULD be treated as
   "invalid attributes".

   Name

      enum

   Value

      2

   Length

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      Four octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Value                                                     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.3.  time

   The "time" data type encodes time as a 32-bit unsigned value in
   network byte order and in seconds since 00:00:00 UTC, January 1,
   1970.  We note that dates before the year 2016 are likely to indicate
   configuration errors, or lack of access to the correct time.

   Note that the "time" attribute is defined to be unsigned, which means
   it is not subject to a signed integer overflow in the year 2038.

   Name

      time

   Value

      3

   Length

      Four octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Time                                                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.4.  text

   The "text" data type encodes UTF-8 text [RFC3629].  The maximum
   length of the text is given by the encapsulating attribute.  Where
   the range of lengths for a particular attribute is limited to a sub-
   set of possible lengths, specifications MUST define the valid

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   range(s).  Attributes with length outside of the allowed values
   SHOULD be treated as "invalid attributes".

   Attributes of type "text" which are allocated in the standard space
   (Section 1.2 of [RFC6929]) are limited to no more than 253 octets of
   data.  Attributes of type "text" which are allocated in the extended
   space can be longer.  In both cases, these limits are reduced when
   the data is encapsulated inside of an another attribute.

   Where the text is intended to carry data in a particular format,
   (e.g. Framed-Route), the format MUST be given.  The specification
   SHOULD describe the format in a machine-readable way, such as via
   Augmented Backus-Naur Form (ABNF) [RFC5234].  Attributes with values
   not matching the defined format SHOULD be treated as "invalid
   attributes".

   Note that the "text" data type does not terminate with a NUL octet
   (hex 00).  The Attribute has a Length field and does not use a
   terminator.  Texts of length zero (0) MUST NOT be sent; omit the
   entire attribute instead.

   Name

      text

   Value

      4

   Length

      One or more octets.

   Format

       0
       0 1 2 3 4 5 6 7
      +-+-+-+-+-+-+-+-
      |  Value    ...
      +-+-+-+-+-+-+-+-

3.5.  string

   The "string" data type encodes binary data, as a sequence of
   undistinguished octets.  Where the range of lengths for a particular
   attribute is limited to a sub-set of possible lengths, specifications
   MUST define the valid range(s).  Attributes with length outside of

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   the allowed values SHOULD be treated as "invalid attributes".

   Attributes of type "string" which are allocated in the standard space
   (Section 1.2 of [RFC6929]) are limited to no more than 253 octets of
   data.  Attributes of type "string" which are allocated in the
   extended space can be longer.  In both cases, these limits are
   reduced when the data is encapsulated inside of an another attribute.

   Note that the "string" data type does not terminate with a NUL octet
   (hex 00).  The Attribute has a Length field and does not use a
   terminator.  Strings of length zero (0) MUST NOT be sent; omit the
   entire attribute instead.  a Where there is a need to encapsulate
   complex data structures, and TLVs cannot be used, the "string" data
   type MUST be used.  This requirement includes encapsulation of data
   structures defined outside of RADIUS, which are opaque to the RADIUS
   infrastucture.  It also includes encapsulation of some data
   structures which are not opaque to RADIUS, such as the contents of
   CHAP-Password.

   There is little reason to define a new RADIUS data type for only one
   attribute.  However, where the complex data type cannot be
   represented as TLVs, and is expected to be used in many attributes, a
   new data type SHOULD be defined.

   These requirements are stronger than [RFC6158], which makes the above
   encapsulation a "SHOULD".  This document defines data types for use
   in RADIUS, so there are few reasons to avoid using them.

   Name

      string

   Value

      5

   Length

      One or more octets.

   Format

       0
       0 1 2 3 4 5 6 7
      +-+-+-+-+-+-+-+-
      |  Octets    ...
      +-+-+-+-+-+-+-+-

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3.6.  concat

   The "concat" data type permits the transport of more than 253 octets
   of data in a "standard space" [RFC6929] attribute.  It is otherwise
   identical to the "string" data type.

   If multiple attributes of this data type are contained in a packet,
   all attributes of the same type code MUST be in order and they MUST
   be consecutive attributes in the packet.

   The amount of data transported in a "concat" data type can be no more
   than the RADIUS packet size.  In practice, the requirement to
   transport multiple attributes means that the limit may be
   substantially smaller than one RADIUS packet.  As a rough guide, is
   RECOMMENDED that this data type transport no more than 2048 octets of
   data.

   The "concat" data type MAY be used for "standard space" attributes.
   It MUST NOT be used for attributes in the "short extended space" or
   the "long extended space".  It MUST NOT be used in any field or
   subfields of the following data types: "tlv", "vsa", "extended",
   "long-extended", or "evs".

   Name

      concat

   Value

      6

   Length

      One or more octets.

   Format

       0
       0 1 2 3 4 5 6 7
      +-+-+-+-+-+-+-+-
      |  Octets    ...
      +-+-+-+-+-+-+-+-

3.7.  ifid

   The "ifid" data type encodes an Interface-Id as an 8 octet IPv6
   Interface Identifier network byte order.

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   Name

      ifid

   Value

      7

   Length

      Eight octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Interface-ID ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Interface-ID                                           |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.8.  ipv4addr

   The "ipv4addr" data type encodes an IPv4 address in network byte
   order.  Where the range of address for a particular attribute is
   limited to a sub-set of possible addresses, specifications MUST
   define the valid range(s).  Attributes with Addresses outside of the
   allowed range(s) SHOULD be treated as "invalid attributes".

   Name

      ipv4addr

   Value

      8

   Length

      Four octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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      |     Address                                                   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.9.  ipv6addr

   The "ipv6addr" data type encodes an IPv6 address in network byte
   order.  Where the range of address for a particular attribute is
   limited to a sub-set of possible addresses, specifications MUST
   define the valid range(s).  Attributes with Addresses outside of the
   allowed range(s) SHOULD be treated as "invalid attributes".

   Name

      ipv6addr

   Value

      9

   Length

      Sixteen octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Address ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Address ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Address ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Address                                                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.10.  ipv6prefix

   The "ipv6prefix" data type encodes an IPv6 prefix, using both a
   prefix length and an IPv6 address in network byte order.  Where the
   range of prefixes for a particular attribute is limited to a sub-set
   of possible prefixes, specifications MUST define the valid range(s).
   Attributes with Addresses outside of the allowed range(s) SHOULD be
   treated as "invalid attributes".

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   Attributes with a Prefix-Length field having value greater than 128
   MUST be treated as "invalid attributes".

   Name

      ipv6prefix

   Value

      10

   Length

      At least two, and no more than eighteen octets.

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Reserved   | Prefix-Length |  Prefix ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Prefix ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Prefix ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Prefix                                                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      Reserved

         This field, which is reserved and MUST be present, is always
         set to zero.  This field is one octet in length.

      Prefix-Length

         The length of the prefix, in bits.  At least 0 and no larger
         than 128.  This field is one octet in length.

      Prefix

         The Prefix field is up to 16 octets in length.  Bits outside of
         the Prefix-Length, if included, MUST be zero.

         The Prefix field SHOULD NOT contain more octets than necessary
         to encode the Prefix.

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3.11.  ipv4prefix

   The "ipv4prefix" data type encodes an IPv4 prefix, using both a
   prefix length and an IPv4 address in network byte order.  Where the
   range of prefixes for a particular attribute is limited to a sub-set
   of possible prefixes, specifications MUST define the valid range(s).
   Attributes with Addresses outside of the allowed range(s) SHOULD be
   treated as "invalid attributes".

   Attributes with a Prefix-Length field having value greater than 32
   MUST be treated as "invalid attributes".

   Name

      ipv4prefix

   Value

      11

   Length

      six octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |    Reserved   | Prefix-Length |  Prefix ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           ... Prefix                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      Reserved

         This field, which is reserved and MUST be present, is always
         set to zero.  This field is one octet in length.

         Note that this definition differs from that given in [RFC6572].
         See Prefix-Length, below, for an explanation.

      Prefix-Length

         The length of the prefix, in bits.  The values MUST be no
         larger than 32.  This field is one octet in length.

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         Note that this definition differs from that given in [RFC6572].

         As compared to [RFC6572], the Prefix-Length field has increased
         in size by two bits, both of which must be zero.  The Reserved
         field has decreased in size by two bits.  The result is that
         both fields are aligned on octet boundaries, which removes the
         need for bit masking of the fields.

         Since [RFC6572] required the Reserved field to be zero, the
         definition here is compatible with the definition in the
         original specification.

      Prefix

         The Prefix field is 4 octets in length.  Bits outside of the
         Prefix-Length MUST be zero.  Unlike the "ipv6prefix" data type,
         this field is fixed length.  If the address is all zeros (i.e.
         "0.0.0.0", then the Prefix-Length MUST be set to 32.

3.12.  integer64

   The "integer64" data type encodes a 64-bit unsigned integer in
   network byte order.  Where the range of values for a particular
   attribute is limited to a sub-set of the values, specifications MUST
   define the valid range(s).  Attributes with Values outside of the
   allowed range(s) SHOULD be treated as "invalid attributes".

   Name

      integer64

   Value

      12

   Length

      Eight octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Value ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            ... Value                                                 |

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      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

3.13.  tlv

   The "tlv" data type encodes a type-length-value, as defined in
   [RFC6929] Section 2.3.

   Name

      tlv

   Value

      13

   Length

      Three or more octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |   TLV-Type    |  TLV-Length   |     TLV-Data ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      TLV-Type

         This field is one octet.  Up-to-date values of this field are
         specified according to the policies and rules described in
         [RFC6929] Section 10.  Values of 254-255 are "Reserved" for use
         by future extensions to RADIUS.  The value 26 has no special
         meaning, and MUST NOT be treated as a Vendor Specific
         attribute.

         The TLV-Type is meaningful only within the context defined by
         "Type" fields of the encapsulating Attributes, using the
         dotted-number notation introduced in [RFC6929].

         A RADIUS server MAY ignore Attributes with an unknown "TLV-
         Type".

         A RADIUS client MAY ignore Attributes with an unknown "TLV-
         Type".

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         A RADIUS proxy SHOULD forward Attributes with an unknown "TLV-
         Type" verbatim.

      TLV-Length

         The TLV-Length field is one octet, and indicates the length of
         this TLV including the TLV-Type, TLV-Length and TLV-Value
         fields.  It MUST have a value between 3 and 255.  If a client
         or server receives a TLV with an invalid TLV-Length, then the
         attribute which encapsulates that TLV MUST be considered to be
         an "invalid attribute", and handled as per [RFC6929] Section
         2.8.

         TLVs having TLV-Length of two (2) MUST NOT be sent; omit the
         entire TLV instead.

      TLV-Data

         The TLV-Data field is one or more octets and contains
         information specific to the Attribute.  The format and length
         of the TLV-Data field is determined by the TLV-Type and TLV-
         Length fields.

         The TLV-Data field MUST contain only known RADIUS data types.
         The TLV-Data field MUST NOT contain any of the following data
         types: "concat", "vsa", "extended", "long-extended", or "evs".

3.14.  vsa

   The "vsa" data type encodes Vendor-Specific data, as given in
   [RFC2865] Section 5.26.  It is used only in the Attr-Data field of a
   Vendor-Specific Attribute.  It MUST NOT appear in the contents of any
   other data type.

   Where an implementation determines that an attribute of data type
   "vsa" contains data which does not match the expected format, it
   SHOULD treat that attribute as being an "invalid attribute".

   Name

      vsa

   Value

      14

   Length

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      Five or more octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            Vendor-Id                          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  VSA-Data ....
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      Vendor-Id

         The 4 octets are the Network Management Private Enterprise Code
         [PEN] of the Vendor in network byte order.

      VSA-Data

         The VSA-Data field is one or more octets.  The actual format of
         the information is site or application specific, and a robust
         implementation SHOULD support the field as undistinguished
         octets.

         The codification of the range of allowed usage of this field is
         outside the scope of this specification.

         The "vsa" data type SHOULD contain as a sequence of "tlv" data
         types.  The interpretation of the TLV-Type and TLV-Data fields
         are dependent on the vendor's definition of that attribute.

         The "vsa" data type MUST be used as contents of the Attr-Data
         field of the Vendor-Specific attribute.  The "vsa" data type
         MUST NOT appear in the contents of any other data type.

3.15.  extended

   The "extended" data type encodes the "Extended Type" format, as given
   in [RFC6929] Section 2.1.  It is used only in the Attr-Data field of
   an Attribute allocated from the "standard space".  It MUST NOT appear
   in the contents of any other data type.

   Name

      extended

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   Value

      15

   Length

      Two or more octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Extended-Type | Ext-Data ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      Extended-Type

         The Extended-Type field is one octet.  Up-to-date values of
         this field are specified according to the policies and rules
         described in [RFC6929] Section 10.  Unlike the Type field
         defined in [RFC2865] Section 5, no values are allocated for
         experimental or implementation-specific use.  Values 241-255
         are reserved and MUST NOT be used.

         The Extended-Type is meaningful only within a context defined
         by the Type field.  That is, this field may be thought of as
         defining a new type space of the form "Type.Extended-Type".
         See [RFC6929] Section 2.5 for additional discussion.

         A RADIUS server MAY ignore Attributes with an unknown
         "Type.Extended-Type".

         A RADIUS client MAY ignore Attributes with an unknown
         "Type.Extended-Type".

      Ext-Data

         The contents of this field MUST be a valid data type as defined
         in the RADIUS Data Type registry.  The Ext-Data field MUST NOT
         contain any of the following data types: "concat", "vsa",
         "extended", "long-extended", or "evs".

         The Ext-Data field is one or more octets.

         Implementations supporting this specification MUST use the

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         Identifier of "Type.Extended-Type" to determine the
         interpretation of the Ext-Data field.

3.16.  long-extended

   The "long-extended" data type encodes the "Long Extended Type"
   format, as given in [RFC6929] Section 2.2.  It is used only in the
   Attr-Data field of an Attribute.  It MUST NOT appear in the contents
   of any other data type.

   Name

      long-extended

   Value

      16

   Length

      Three or more octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | Extended-Type |M|T| Reserved  | Ext-Data ...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      Extended-Type

         This field is identical to the Extended-Type field defined
         above in Section 3.15.

      M (More)

         The More field is one (1) bit in length, and indicates whether
         or not the current attribute contains "more" than 251 octets of
         data.  The More field MUST be clear (0) if the Length field has
         value less than 255.  The More field MAY be set (1) if the
         Length field has value of 255.

         If the More field is set (1), it indicates that the Ext-Data
         field has been fragmented across multiple RADIUS attributes.

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         When the More field is set (1), the attribute MUST have a
         Length field of value 255; there MUST be an attribute following
         this one; and the next attribute MUST have both the same Type
         and Extended Type.  That is, multiple fragments of the same
         value MUST be in order and MUST be consecutive attributes in
         the packet, and the last attribute in a packet MUST NOT have
         the More field set (1).

         That is, a packet containing a fragmented attribute needs to
         contain all fragments of the attribute, and those fragments
         need to be contiguous in the packet.  RADIUS does not support
         inter-packet fragmentation, which means that fragmenting an
         attribute across multiple packets is impossible.

         If a client or server receives an attribute fragment with the
         "More" field set (1), but for which no subsequent fragment can
         be found, then the fragmented attribute is considered to be an
         "invalid attribute", and handled as per [RFC6929] Section 2.8.

      T (Truncation)

                                    This field is one bit in size and is
                                    called "T" for Truncation.  It
                                    indicates that the attribute is
                                    intentionally truncated in this
                                    chunk and is to be continued in the
                                    next chunk of the sequence.  The
                                    combination of the M flag and the T
                                    flag indicates that the attribute is
                                    fragmented (M flag) but that all the
                                    fragments are not available in this
                                    chunk (T flag).  Proxies
                                    implementing [RFC6929] will see
                                    these attributes as invalid (they
                                    will not be able to reconstruct
                                    them), but they will still forward
                                    them, as Section 5.2 of [RFC6929]
                                    indicates that they SHOULD forward
                                    unknown attributes anyway.

                                    Please see [RFC7499] for further
                                    discussion of the uses of this flag.

                                 Reserved

                                    This field is 6 bits long, and is
                                    reserved for future use.
                                    Implementations MUST set it to zero

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                                    (0) when encoding an attribute for
                                    sending in a packet.  The contents
                                    SHOULD be ignored on reception.

                                    Future specifications may define
                                    additional meaning for this field.
                                    Implementations therefore MUST NOT
                                    treat this field as invalid if it is
                                    non-zero.

                                 Ext-Data

                                    The contents of this field MUST be a
                                    valid data type as defined in the
                                    RADIUS Data Type registry. The Ext-
                                    Data field MUST NOT contain any of
                                    the following data types: "concat",
                                    "vsa", "extended", "long-extended",
                                    or "evs".

                                    The Ext-Data field is one or more
                                    octets.

                                    Implementations supporting this
                                    specification MUST use the
                                    Identifier of "Type.Extended-Type"
                                    to determine the interpretation of
                                    the Ext-Data field.

                                    The length of the data MUST be taken
                                    as the sum of the lengths of the
                                    fragments (i.e. Ext-Data fields)
                                    from which it is constructed.  Any
                                    interpretation of the resulting data
                                    MUST occur after the fragments have
                                    been reassembled.  If the
                                    reassembled data does not match the
                                    expected format, each fragment MUST
                                    be treated as an "invalid
                                    attribute", and the reassembled data
                                    MUST be discarded.

                                    We note that the maximum size of a
                                    fragmented attribute is limited only
                                    by the RADIUS packet length
                                    limitation.  Implementations MUST be
                                    able to handle the case where one
                                    fragmented attribute completely

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                                    fills the packet.

3.17.  evs

   The "evs" data type encodes an "Extended Vendor-Specific" attribute,
   as given in [RFC6929] Section 2.4.  The "evs" data type is used
   solely to extend the Vendor Specific space.  It MAY appear inside of
   an "extended" or a "long-extended" data type.  It MUST NOT appear in
   the contents of any other data type.

   Where an implementation determines that an attribute of data type
   "evs" contains data which does not match the expected format, it
   SHOULD treat that attribute as being an "invalid attribute".

   Name

      evs

   Value

      17

   Length

      Six or more octets

   Format

       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            Vendor-Id                          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Vendor-Type   |  EVS-Data ....
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Subfields

      Vendor-Id

         The 4 octets are the Network Management Private Enterprise Code
         [PEN] of the Vendor in network byte order.

      Vendor-Type

         The Vendor-Type field is one octet.  Values are assigned at the
         sole discretion of the Vendor.

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      EVS-Data

         The EVS-Data field is one or more octets.  It SHOULD
         encapsulate a previously defined RADIUS data type.  Non-
         standard data types SHOULD NOT be used.  We note that the EVS-
         Data field may be of data type "tlv".

         The actual format of the information is site or application
         specific, and a robust implementation SHOULD support the field
         as undistinguished octets.  We recognise that Vendors have
         complete control over the contents and format of the Ext-Data
         field, while at the same time recommending that good practices
         be followed.

         Further codification of the range of allowed usage of this
         field is outside the scope of this specification.

4.  Updated Registries

   This section defines a new IANA registry for RADIUS data types, and
   then updates the existing RADIUS Attribute Type registry to use the
   data types from the new registry.

4.1.  Create a Data Type Registry

   This section defines a new registry located under "RADIUS Types",
   called "Data Type".  The "Registration Procedures" for the Data Type
   registry are "Standards Action".

   The Data Type registry contains three columns of data, as follows.

   Value

      The number of the data type.  The value field is an artifact of
      the registry, and has no on-the-wire meaning.

   Name

      The name of the data type.  The name field is used only for the
      registry, and has no on-the-wire meaning.

   Reference

      The specification where the data type was defined.

   The initial contents of the registry are as follows.

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   Value  Description    Reference
   -----  -----------    ----------------
       1  integer        [RFC2865], TBD
       2  enum           [RFC2865], TBD
       3  time           [RFC2865], TBD
       4  text           [RFC2865], TBD
       5  string         [RFC2865], TBD
       6  concat         TBD
       7  ifid           [RFC3162], TBD
       8  ipv4addr       [RFC2865], TBD
       9  ipv6addr       [RFC3162], TBD
      10  ipv6prefix     [RFC3162], TBD
      11  ipv4prefix     [RFC6572], TBD
      12  integer64      [RFC6929], TBD
      13  tlv            [RFC6929], TBD
      14  evs            [RFC6929], TBD
      15  extended       [RFC6929], TBD
      16  long-extended  [RFC6929], TBD

4.2.  Updates to the Attribute Type Registry

   This section updates the RADIUS Attribute Type registry to have a new
   column, which is inserted in between the existing "Description" and
   "Reference" columns.  The new column is named "Data Type".  The
   contents of that column are the name of a data type, corresponding to
   the attribute in that row, or blank if the attribute type is
   unassigned.  The name of the data type is taken from the RADIUS Data
   Type registry, as defined above.

   The existing registration requirements for the RADIUS Attribute Type
   registry are otherwise unchanged.

NOTE TO RFC EDITOR: Before the document is published, please remove this
note, and the following text in this section.

   The updated registry follows in CSV format.

   Value,Description,Data Type,Reference
   1,User-Name,text,[RFC2865]
   2,User-Password,string,[RFC2865]
   3,CHAP-Password,string,[RFC2865]
   4,NAS-IP-Address,ipv4addr,[RFC2865]
   5,NAS-Port,integer,[RFC2865]
   6,Service-Type,enum,[RFC2865]
   7,Framed-Protocol,enum,[RFC2865]
   8,Framed-IP-Address,ipv4addr,[RFC2865]
   9,Framed-IP-Netmask,ipv4addr,[RFC2865]
   10,Framed-Routing,enum,[RFC2865]

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   11,Filter-Id,text,[RFC2865]
   12,Framed-MTU,integer,[RFC2865]
   13,Framed-Compression,enum,[RFC2865]
   14,Login-IP-Host,ipv4addr,[RFC2865]
   15,Login-Service,enum,[RFC2865]
   16,Login-TCP-Port,integer,[RFC2865]
   17,Unassigned,,
   18,Reply-Message,text,[RFC2865]
   19,Callback-Number,text,[RFC2865]
   20,Callback-Id,text,[RFC2865]
   21,Unassigned,,
   22,Framed-Route,text,[RFC2865]
   23,Framed-IPX-Network,ipv4addr,[RFC2865]
   24,State,string,[RFC2865]
   25,Class,string,[RFC2865]
   26,Vendor-Specific,vsa,[RFC2865]
   27,Session-Timeout,integer,[RFC2865]
   28,Idle-Timeout,integer,[RFC2865]
   29,Termination-Action,enum,[RFC2865]
   30,Called-Station-Id,text,[RFC2865]
   31,Calling-Station-Id,text,[RFC2865]
   32,NAS-Identifier,text,[RFC2865]
   33,Proxy-State,string,[RFC2865]
   34,Login-LAT-Service,text,[RFC2865]
   35,Login-LAT-Node,text,[RFC2865]
   36,Login-LAT-Group,string,[RFC2865]
   37,Framed-AppleTalk-Link,integer,[RFC2865]
   38,Framed-AppleTalk-Network,integer,[RFC2865]
   39,Framed-AppleTalk-Zone,text,[RFC2865]
   40,Acct-Status-Type,enum,[RFC2866]
   41,Acct-Delay-Time,integer,[RFC2866]
   42,Acct-Input-Octets,integer,[RFC2866]
   43,Acct-Output-Octets,integer,[RFC2866]
   44,Acct-Session-Id,text,[RFC2866]
   45,Acct-Authentic,enum,[RFC2866]
   46,Acct-Session-Time,integer,[RFC2866]
   47,Acct-Input-Packets,integer,[RFC2866]
   48,Acct-Output-Packets,integer,[RFC2866]
   49,Acct-Terminate-Cause,enum,[RFC2866]
   50,Acct-Multi-Session-Id,text,[RFC2866]
   51,Acct-Link-Count,integer,[RFC2866]
   52,Acct-Input-Gigawords,integer,[RFC2869]
   53,Acct-Output-Gigawords,integer,[RFC2869]
   54,Unassigned,,
   55,Event-Timestamp,time,[RFC2869]
   56,Egress-VLANID,integer,[RFC4675]
   57,Ingress-Filters,enum,[RFC4675]
   58,Egress-VLAN-Name,text,[RFC4675]

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   59,User-Priority-Table,string,[RFC4675]
   60,CHAP-Challenge,string,[RFC2865]
   61,NAS-Port-Type,enum,[RFC2865]
   62,Port-Limit,integer,[RFC2865]
   63,Login-LAT-Port,text,[RFC2865]
   64,Tunnel-Type,enum,[RFC2868]
   65,Tunnel-Medium-Type,enum,[RFC2868]
   66,Tunnel-Client-Endpoint,text,[RFC2868]
   67,Tunnel-Server-Endpoint,text,[RFC2868]
   68,Acct-Tunnel-Connection,text,[RFC2867]
   69,Tunnel-Password,string,[RFC2868]
   70,ARAP-Password,string,[RFC2869]
   71,ARAP-Features,string,[RFC2869]
   72,ARAP-Zone-Access,enum,[RFC2869]
   73,ARAP-Security,integer,[RFC2869]
   74,ARAP-Security-Data,text,[RFC2869]
   75,Password-Retry,integer,[RFC2869]
   76,Prompt,enum,[RFC2869]
   77,Connect-Info,text,[RFC2869]
   78,Configuration-Token,text,[RFC2869]
   79,EAP-Message,concat,[RFC2869]
   80,Message-Authenticator,string,[RFC2869]
   81,Tunnel-Private-Group-ID,text,[RFC2868]
   82,Tunnel-Assignment-ID,text,[RFC2868]
   83,Tunnel-Preference,integer,[RFC2868]
   84,ARAP-Challenge-Response,string,[RFC2869]
   85,Acct-Interim-Interval,integer,[RFC2869]
   86,Acct-Tunnel-Packets-Lost,integer,[RFC2867]
   87,NAS-Port-Id,text,[RFC2869]
   88,Framed-Pool,text,[RFC2869]
   89,CUI,string,[RFC4372]
   90,Tunnel-Client-Auth-ID,text,[RFC2868]
   91,Tunnel-Server-Auth-ID,text,[RFC2868]
   92,NAS-Filter-Rule,text,[RFC4849]
   93,Unassigned,,
   94,Originating-Line-Info,string,[RFC7155]
   95,NAS-IPv6-Address,ipv6addr,[RFC3162]
   96,Framed-Interface-Id,ifid,[RFC3162]
   97,Framed-IPv6-Prefix,ipv6prefix,[RFC3162]
   98,Login-IPv6-Host,ipv6addr,[RFC3162]
   99,Framed-IPv6-Route,text,[RFC3162]
   100,Framed-IPv6-Pool,text,[RFC3162]
   101,Error-Cause Attribute,enum,[RFC3576]
   102,EAP-Key-Name,string,[RFC4072][RFC7268]
   103,Digest-Response,text,[RFC5090]
   104,Digest-Realm,text,[RFC5090]
   105,Digest-Nonce,text,[RFC5090]
   106,Digest-Response-Auth,text,[RFC5090]

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   107,Digest-Nextnonce,text,[RFC5090]
   108,Digest-Method,text,[RFC5090]
   109,Digest-URI,text,[RFC5090]
   110,Digest-Qop,text,[RFC5090]
   111,Digest-Algorithm,text,[RFC5090]
   112,Digest-Entity-Body-Hash,text,[RFC5090]
   113,Digest-CNonce,text,[RFC5090]
   114,Digest-Nonce-Count,text,[RFC5090]
   115,Digest-Username,text,[RFC5090]
   116,Digest-Opaque,text,[RFC5090]
   117,Digest-Auth-Param,text,[RFC5090]
   118,Digest-AKA-Auts,text,[RFC5090]
   119,Digest-Domain,text,[RFC5090]
   120,Digest-Stale,text,[RFC5090]
   121,Digest-HA1,text,[RFC5090]
   122,SIP-AOR,text,[RFC5090]
   123,Delegated-IPv6-Prefix,ipv6prefix,[RFC4818]
   124,MIP6-Feature-Vector,string,[RFC5447]
   125,MIP6-Home-Link-Prefix,ipv6prefix,[RFC5447]
   126,Operator-Name,text,[RFC5580]
   127,Location-Information,string,[RFC5580]
   128,Location-Data,string,[RFC5580]
   129,Basic-Location-Policy-Rules,string,[RFC5580]
   130,Extended-Location-Policy-Rules,string,[RFC5580]
   131,Location-Capable,enum,[RFC5580]
   132,Requested-Location-Info,enum,[RFC5580]
   133,Framed-Management-Protocol,enum,[RFC5607]
   134,Management-Transport-Protection,enum,[RFC5607]
   135,Management-Policy-Id,text,[RFC5607]
   136,Management-Privilege-Level,integer,[RFC5607]
   137,PKM-SS-Cert,concat,[RFC5904]
   138,PKM-CA-Cert,concat,[RFC5904]
   139,PKM-Config-Settings,string,[RFC5904]
   140,PKM-Cryptosuite-List,string,[RFC5904]
   141,PKM-SAID,text,[RFC5904]
   142,PKM-SA-Descriptor,string,[RFC5904]
   143,PKM-Auth-Key,string,[RFC5904]
   144,DS-Lite-Tunnel-Name,text,[RFC6519]
   145,Mobile-Node-Identifier,string,[RFC6572]
   146,Service-Selection,text,[RFC6572]
   147,PMIP6-Home-LMA-IPv6-Address,ipv6addr,[RFC6572]
   148,PMIP6-Visited-LMA-IPv6-Address,ipv6addr,[RFC6572]
   149,PMIP6-Home-LMA-IPv4-Address,ipv4addr,[RFC6572]
   150,PMIP6-Visited-LMA-IPv4-Address,ipv4addr,[RFC6572]
   151,PMIP6-Home-HN-Prefix,ipv6prefix,[RFC6572]
   152,PMIP6-Visited-HN-Prefix,ipv6prefix,[RFC6572]
   153,PMIP6-Home-Interface-ID,ifid,[RFC6572]
   154,PMIP6-Visited-Interface-ID,ifid,[RFC6572]

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   155,PMIP6-Home-IPv4-HoA,ipv4prefix,[RFC6572]
   156,PMIP6-Visited-IPv4-HoA,ipv4prefix,[RFC6572]
   157,PMIP6-Home-DHCP4-Server-Address,ipv4addr,[RFC6572]
   158,PMIP6-Visited-DHCP4-Server-Address,ipv4addr,[RFC6572]
   159,PMIP6-Home-DHCP6-Server-Address,ipv6addr,[RFC6572]
   160,PMIP6-Visited-DHCP6-Server-Address,ipv6addr,[RFC6572]
   161,PMIP6-Home-IPv4-Gateway,ipv4addr,[RFC6572]
   162,PMIP6-Visited-IPv4-Gateway,ipv4addr,[RFC6572]
   163,EAP-Lower-Layer,enum,[RFC6677]
   164,GSS-Acceptor-Service-Name,text,[RFC7055]
   165,GSS-Acceptor-Host-Name,text,[RFC7055]
   166,GSS-Acceptor-Service-Specifics,text,[RFC7055]
   167,GSS-Acceptor-Realm-Name,text,[RFC7055]
   168,Framed-IPv6-Address,ipv6addr,[RFC6911]
   169,DNS-Server-IPv6-Address,ipv6addr,[RFC6911]
   170,Route-IPv6-Information,ipv6prefix,[RFC6911]
   171,Delegated-IPv6-Prefix-Pool,text,[RFC6911]
   172,Stateful-IPv6-Address-Pool,text,[RFC6911]
   173,IPv6-6rd-Configuration,tlv,[RFC6930]
   174,Allowed-Called-Station-Id,text,[RFC7268]
   175,EAP-Peer-Id,string,[RFC7268]
   176,EAP-Server-Id,string,[RFC7268]
   177,Mobility-Domain-Id,integer,[RFC7268]
   178,Preauth-Timeout,integer,[RFC7268]
   179,Network-Id-Name,string,[RFC7268]
   180,EAPoL-Announcement,concat,[RFC7268]
   181,WLAN-HESSID,text,[RFC7268]
   182,WLAN-Venue-Info,integer,[RFC7268]
   183,WLAN-Venue-Language,string,[RFC7268]
   184,WLAN-Venue-Name,text,[RFC7268]
   185,WLAN-Reason-Code,integer,[RFC7268]
   186,WLAN-Pairwise-Cipher,integer,[RFC7268]
   187,WLAN-Group-Cipher,integer,[RFC7268]
   188,WLAN-AKM-Suite,integer,[RFC7268]
   189,WLAN-Group-Mgmt-Cipher,integer,[RFC7268]
   190,WLAN-RF-Band,integer,[RFC7268]
   191,Unassigned,,
   192-223,Experimental Use,,[RFC3575]
   224-240,Implementation Specific,,[RFC3575]
   241,Extended-Attribute-1,extended,[RFC6929]
   241.1,Frag-Status,integer,[RFC7499]
   241.2,Proxy-State-Length,integer,[RFC7499]
   241.3,Response-Length,integer,[RFC7930]
   241.4,Original-Packet-Code,integer,[RFC7930]
   241.{5-25},Unassigned,,
   241.26,Extended-Vendor-Specific-1,evs,[RFC6929]
   241.{27-240},Unassigned,,
   241.{241-255},Reserved,,[RFC6929]

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   242,Extended-Attribute-2,extended,[RFC6929]
   242.{1-25},Unassigned,,
   242.26,Extended-Vendor-Specific-2,evs,[RFC6929]
   242.{27-240},Unassigned,,
   242.{241-255},Reserved,,[RFC6929]
   243,Extended-Attribute-3,extended,[RFC6929]
   243.{1-25},Unassigned,,
   243.26,Extended-Vendor-Specific-3,evs,[RFC6929]
   243.{27-240},Unassigned,,
   243.{241-255},Reserved,,[RFC6929]
   244,Extended-Attribute-4,extended,[RFC6929]
   244.{1-25},Unassigned,,
   244.26,Extended-Vendor-Specific-4,evs,[RFC6929]
   244.{27-240},Unassigned,,
   244.{241-255},Reserved,,[RFC6929]
   245,Extended-Attribute-5,long-extended,[RFC6929]
   245.{1-25},Unassigned,,
   245.26,Extended-Vendor-Specific-5,evs,[RFC6929]
   245.{27-240},Unassigned,,
   245.{241-255},Reserved,,[RFC6929]
   246,Extended-Attribute-6,long-extended,[RFC6929]
   246.{1-25},Unassigned,,
   246.26,Extended-Vendor-Specific-6,evs,[RFC6929]
   246.{27-240},Unassigned,,
   246.{241-255},Reserved,,[RFC6929]
   247-255,Reserved,,[RFC3575]

5.  Security Considerations

   This specification is concerned solely with updates to IANA
   registries.  As such, there are no security considerations with the
   document itself.

   However, the use of inconsistent names and poorly-defined entities in
   a protocol is problematic.  Inconsistencies in specifications can
   lead to security and interoperability problems in implementations.
   Further, having one canonical source for the definition of data types
   means an implementor has fewer specifications to read.  The
   implementation work is therefore simpler, and is more likely to be
   correct.

   The goal of this specification is to reduce ambiguities in the RADIUS
   protocol, which we believe will lead to more robust and more secure
   implementations.

DeKok, Alan                  Standards Track                   [Page 36]
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6.  IANA Considerations

   IANA is instructed to create one new registry as described above in
   Section 4.1.  The "TBD" text in that section should be replaced with
   the RFC number of this document when it is published.

   IANA is instructed to update the RADIUS Attribute Type registry, as
   described above in Section 4.2.

   IANA is instructed to require that all allocation requests in the
   RADIUS Attribute Type registry contain a "Data Type" field.  That
   field is required to contain one of the "Data Type" names contained
   in the RADIUS Data Type registry.

   IANA is instructed to require that updates to the RADIUS Data Type
   registry contain the following fields, with the associated
   instructions:

   * Value.  IANA is instructed to assign the next unused integer in
     sequence to new data type definitions.

   * Name.  IANA is instructed to require that this name be unique
     in the registry.

   * Reference.  IANA is instructed to update this field with a
     reference to the document which defines the data type.

7.  References

7.1.  Normative References

[RFC2119]
     Bradner, S., "Key words for use in RFCs to Indicate Requirement
     Levels", RFC 2119, March, 1997.

[RFC2865]
     Rigney, C., Willens, S., Rubens, A. and W. Simpson, "Remote
     Authentication Dial In User Service (RADIUS)", RFC 2865, June 2000.

[RFC3162]
     Aboba, B., Zorn, G., and D. Mitton, "RADIUS and IPv6", RFC 3162,
     August 2001.

[RFC3629]
     Yergeau, F., "UTF-8, a transformation format of ISO 10646", RFC
     3629, November 2003.

DeKok, Alan                  Standards Track                   [Page 37]
INTERNET-DRAFT            Data Types in RADIUS           18 October 2016

[RFC4072]
     Eronen, P., et al, "Diameter Extensible Authentication Protocol
     (EAP) Application", RFC 4072, February 2013.

[RFC6158]
     DeKok, A., and Weber, G., "RADIUS Design Guidelines", RFC 6158,
     March 2011.

[RFC6572]
     Xia, F., et al, "RADIUS Support for Proxy Mobile IPv6", RFC 6572,
     June 2012.

[RFC7499]
     Perez-Mendez, A. Ed., et al, "Support of Fragmentation of RADIUS
     Packets", RFC 7499, April 2015.

7.2.  Informative References

[RFC2868]
     Zorn, G., Leifer, D., Rubens, A., Shriver, J., Holdrege, M., and I.
     Goyret, "RADIUS Attributes for Tunnel Protocol Support", RFC 2868,
     June 2000.

[RFC2869]
     Rigney, C., et al, "RADIUS Extensions", RFC 2869, June 2000.

[RFC5234]
     Crocker, D. and P. Overell, "Augmented BNF for Syntax
     Specifications: ABNF", RFC 5234, January 2008.

[RFC6929]
     DeKok, A., and Lior, A., "Remote Authentication Dial In User
     Service (RADIUS) Protocol Extensions", RFC 6929, April 2013.

[RFC7268]
     Aboba, B, et al, "RADIUS Attributes for IEEE 802 Networks", RFC
     7268, July 2015.

[RFC7499]
     Perez-Mendez A., et al, "Support of Fragmentation of RADIUS
     Packets", RFC 7499, April 2015.

[PEN]
     http://www.iana.org/assignments/enterprise-numbers

Acknowledgments

   Thanks to the RADEXT WG for patience and reviews of this document.

DeKok, Alan                  Standards Track                   [Page 38]
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Authors' Addresses

   Alan DeKok
   The FreeRADIUS Server Project

   Email: aland@freeradius.org

DeKok, Alan                  Standards Track                   [Page 39]