rfc4675.txt

使用最广泛的radius的linux的源码

Network Working Group                                         P. Congdon
Request for Comments: 4675                                    M. Sanchez
Category: Standards Track                        Hewlett-Packard Company
                                                                B. Aboba
                                                   Microsoft Corporation
                                                          September 2006


         RADIUS Attributes for Virtual LAN and Priority Support

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2006).

Abstract

   This document proposes additional Remote Authentication Dial-In User
   Service (RADIUS) attributes for dynamic Virtual LAN assignment and
   prioritization, for use in provisioning of access to IEEE 802 local
   area networks.  These attributes are usable within either RADIUS or
   Diameter.






















Congdon, et al.             Standards Track                     [Page 1]

RFC 4675              VLAN and Priority Attributes        September 2006


Table of Contents

   1. Introduction ....................................................3
      1.1. Terminology ................................................3
      1.2. Requirements Language ......................................3
      1.3. Attribute Interpretation ...................................3
   2. Attributes ......................................................4
      2.1. Egress-VLANID ..............................................4
      2.2. Ingress-Filters ............................................6
      2.3. Egress-VLAN-Name ...........................................7
      2.4. User-Priority-Table ........................................8
   3. Table of Attributes ............................................10
   4. Diameter Considerations ........................................10
   5. IANA Considerations ............................................11
   6. Security Considerations ........................................11
   7. References .....................................................12
      7.1. Normative References ......................................12
      7.2. Informative References ....................................13
   8. Acknowledgements ...............................................13
































Congdon, et al.             Standards Track                     [Page 2]

RFC 4675              VLAN and Priority Attributes        September 2006


1.  Introduction

   This document describes Virtual LAN (VLAN) and re-prioritization
   attributes that may prove useful for provisioning of access to IEEE
   802 local area networks [IEEE-802] with the Remote Authentication
   Dial-In User Service (RADIUS) or Diameter.

   While [RFC3580] enables support for VLAN assignment based on the
   tunnel attributes defined in [RFC2868], it does not provide support
   for a more complete set of VLAN functionality as defined by
   [IEEE-802.1Q].  The attributes defined in this document provide
   support within RADIUS and Diameter analogous to the management
   variables supported in [IEEE-802.1Q] and MIB objects defined in
   [RFC4363].  In addition, this document enables support for a wider
   range of [IEEE-802.1X] configurations.

1.1.  Terminology

   This document uses the following terms:

   Network Access Server (NAS)
        A device that provides an access service for a user to a
        network.  Also known as a RADIUS client.

   RADIUS server
        A RADIUS authentication server is an entity that provides an
        authentication service to a NAS.

   RADIUS proxy
        A RADIUS proxy acts as an authentication server to the NAS, and
        a RADIUS client to the RADIUS server.

1.2.  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].

1.3.  Attribute Interpretation

   The attributes described in this document apply to a single instance
   of a NAS port, or more specifically an IEEE 802.1Q bridge port.
   [IEEE-802.1Q], [IEEE-802.1D], and [IEEE-802.1X] do not recognize
   finer management granularity than "per port".  In some cases, such as
   with IEEE 802.11 wireless LANs, the concept of a "virtual port" is
   used in place of the physical port.  Such virtual ports are typically
   based on security associations and scoped by station, or Media Access
   Control (MAC) address.



Congdon, et al.             Standards Track                     [Page 3]

RFC 4675              VLAN and Priority Attributes        September 2006


   The attributes defined in this document are applied on a per-user
   basis and it is expected that there is a single user per port;
   however, in some cases that port may be a "virtual port".  If a NAS
   implementation conforming to this document supports "virtual ports",
   it may be possible to provision those "virtual ports" with unique
   values of the attributes described in this document, allowing
   multiple users sharing the same physical port to each have a unique
   set of authorization parameters.

   If a NAS conforming to this specification receives an Access-Accept
   packet containing an attribute defined in this document that it
   cannot apply, it MUST act as though it had received an Access-Reject.
   [RFC3576] requires that a NAS receiving a Change of Authorization
   Request (CoA-Request) reply with a CoA-NAK if the Request contains an
   unsupported attribute.  It is recommended that an Error-Cause
   attribute with the value set to "Unsupported Attribute" (401) be
   included in the CoA-NAK.  As noted in [RFC3576], authorization
   changes are atomic so that this situation does not result in session
   termination and the preexisting configuration remains unchanged.  As
   a result, no accounting packets should be generated.

2.  Attributes

2.1.  Egress-VLANID

   Description

      The Egress-VLANID attribute represents an allowed IEEE 802 Egress
      VLANID for this port, indicating if the VLANID is allowed for
      tagged or untagged frames as well as the VLANID.

      As defined in [RFC3580], the VLAN assigned via tunnel attributes
      applies both to the ingress VLANID for untagged packets (known as
      the PVID) and the egress VLANID for untagged packets.  In
      contrast, the Egress-VLANID attribute configures only the egress
      VLANID for either tagged or untagged packets.  The Egress-VLANID
      attribute MAY be included in the same RADIUS packet as [RFC3580]
      tunnel attributes; however, the Egress-VLANID attribute is not
      necessary if it is being used to configure the same untagged
      VLANID included in tunnel attributes.  To configure an untagged
      VLAN for both ingress and egress, the tunnel attributes of
      [RFC3580] MUST be used.

      Multiple Egress-VLANID attributes MAY be included in Access-
      Request, Access-Accept, CoA-Request, or Accounting-Request
      packets; this attribute MUST NOT be sent within an Access-
      Challenge, Access-Reject, Disconnect-Request, Disconnect-ACK,




Congdon, et al.             Standards Track                     [Page 4]

RFC 4675              VLAN and Priority Attributes        September 2006


      Disconnect-NAK, CoA-ACK, or CoA-NAK.  Each attribute adds the
      specified VLAN to the list of allowed egress VLANs for the port.

      The Egress-VLANID attribute is shown below.  The fields are
      transmitted from left to right:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |            Value
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
              Value (cont)            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

      56

   Length

      6

   Value

      The Value field is four octets.  The format is described below:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Tag Indic.   |        Pad            |       VLANID          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      The Tag Indication field is one octet in length and indicates
      whether the frames on the VLAN are tagged (0x31) or untagged
      (0x32).  The Pad field is 12 bits in length and MUST be 0 (zero).
      The VLANID is 12 bits in length and contains the [IEEE-802.1Q]
      VLAN VID value.














Congdon, et al.             Standards Track                     [Page 5]

RFC 4675              VLAN and Priority Attributes        September 2006


2.2.  Ingress-Filters

   Description

      The Ingress-Filters attribute corresponds to the Ingress Filter
      per-port variable defined in [IEEE-802.1Q] clause 8.4.5.  When the
      attribute has the value "Enabled", the set of VLANs that are
      allowed to ingress a port must match the set of VLANs that are
      allowed to egress a port.  Only a single Ingress-Filters attribute
      MAY be sent within an Access-Request, Access-Accept, CoA-Request,
      or Accounting-Request packet; this attribute MUST NOT be sent
      within an Access-Challenge, Access-Reject, Disconnect-Request,
      Disconnect-ACK, Disconnect-NAK, CoA-ACK, or CoA-NAK.

      The Ingress-Filters attribute is shown below.  The fields are
      transmitted from left to right:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |         Value
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
              Value (cont)            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

      57

   Length

      6

   Value

      The Value field is four octets.  Supported values include:

      1 - Enabled
      2 - Disabled












Congdon, et al.             Standards Track                     [Page 6]

RFC 4675              VLAN and Priority Attributes        September 2006


2.3.  Egress-VLAN-Name

   Description

      Clause 12.10.2.1.3 (a) in [IEEE-802.1Q] describes the
      administratively assigned VLAN Name associated with a VLAN-ID
      defined within an IEEE 802.1Q bridge.  The Egress-VLAN-Name
      attribute represents an allowed VLAN for this port.  It is similar
      to the Egress-VLANID attribute, except that the VLAN-ID itself is
      not specified or known; rather, the VLAN name is used to identify
      the VLAN within the system.

      The tunnel attributes described in [RFC3580] and the Egress-VLAN-
      Name attribute both can be used to configure the egress VLAN for
      untagged packets.  These attributes can be used concurrently and
      MAY appear in the same RADIUS packet.  When they do appear
      concurrently, the list of allowed VLANs is the concatenation of
      the Egress-VLAN-Name and the Tunnel-Private-Group-ID (81)
      attributes.  The Egress-VLAN-Name attribute does not alter the
      ingress VLAN for untagged traffic on a port (also known as the
      PVID).  The tunnel attributes from [RFC3580] should be relied upon
      instead to set the PVID.

      The Egress-VLAN-Name attribute contains two parts; the first part
      indicates if frames on the VLAN for this port are to be
      represented in tagged or untagged format, the second part is the
      VLAN name.

      Multiple Egress-VLAN-Name attributes MAY be included within an
      Access-Request, Access-Accept, CoA-Request, or Accounting-Request
      packet; this attribute MUST NOT be sent within an Access-
      Challenge, Access-Reject, Disconnect-Request, Disconnect-ACK,
      Disconnect-NAK, CoA-ACK, or CoA-NAK.  Each attribute adds the
      named VLAN to the list of allowed egress VLANs for the port.  The
      Egress-VLAN-Name attribute is shown below.  The fields are
      transmitted from left to right:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |     Type      |    Length     |   Tag Indic.  |   String...
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Type

      58





Congdon, et al.             Standards Track                     [Page 7]

RFC 4675              VLAN and Priority Attributes        September 2006


   Length

      >=4

   Tag Indication

      The Tag Indication field is one octet in length and indicates
      whether the frames on the VLAN are tagged (0x31, ASCII '1') or
      untagged (0x32, ASCII '2').  These values were chosen so as to
      make them easier for users to enter.

   String

      The String field is at least one octet in length and contains the
      VLAN Name as defined in [IEEE-802.1Q] clause 12.10.2.1.3 (a).
      [RFC3629] UTF-8 encoded 10646 characters are RECOMMENDED, but a
      robust implementation SHOULD support the field as undistinguished
      octets.

2.4.  User-Priority-Table

   Description

      [IEEE-802.1D] clause 7.5.1 discusses how to regenerate (or re-map)