RADIUS Working Group Glen Zorn INTERNET-DRAFT Microsoft Category: Standards Track Bernard Aboba Microsoft 11 November 1998 RADIUS Authentication Server MIB 1. Status of this Memo This document is an Internet-Draft. Internet-Drafts are working docu- ments of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute work- ing 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 mate- rial or to cite them other than as ``work in progress.'' To learn the current status of any Internet-Draft, please check the ``1id-abstracts.txt'' listing contained in the Internet-Drafts Shadow Directories on ftp.ietf.org (US East Coast), nic.nordu.net (Europe), ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim). The distribution of this memo is unlimited. It is filed as , and expires May 1, 1999. Please send comments to the authors. 2. Copyright Notice Copyright (C) The Internet Society (1998). All Rights Reserved. 3. Abstract This memo defines a set of extensions which instrument RADIUS authen- tication server functions. These extensions represent a portion of the Management Information Base (MIB) for use with network management pro- tocols in the Internet community. Using these extensions IP-based management stations can manage RADIUS authentication servers. 4. Introduction This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used for managing RADIUS authentication servers. Zorn & Aboba Standards Track [Page 1] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 RADIUS authentication servers are today widely deployed by dialup Internet Service Providers, in order to provide authentication ser- vices. As a result, the effective management of RADIUS authentication servers is of considerable importance. 5. The SNMP Management Framework The SNMP Management Framework presently consists of five major compo- nents: o An overall architecture, described in RFC 2271 [1]. o Mechanisms for describing and naming objects and events for the purpose of management. The first version of this Structure of Management Information (SMI) is called SMIv1 and described in RFC 1155 [2], RFC 1212 [3] and RFC 1215 [4]. The second version, called SMIv2, is described in RFC 1902 [5], RFC 1903 [6] and RFC 1904 [7]. o Message protocols for transferring management information. The first version of the SNMP message protocol is called SNMPv1 and described in RFC 1157 [8]. A second version of the SNMP message protocol, which is not an Internet standards track protocol, is called SNMPv2c and described in RFC 1901 [9] and RFC 1906 [10]. The third version of the message protocol is called SNMPv3 and described in RFC 1906 [10], RFC 2272 [11] and RFC 2274 [12]. o Protocol operations for accessing management information. The first set of protocol operations and associated PDU formats is described in RFC 1157 [8]. A second set of protocol operations and associated PDU formats is described in RFC 1905 [13]. o A set of fundamental applications described in RFC 2273 [14] and the view-based access control mechanism described in RFC 2275 [15]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the mechanisms defined in the SMI. This memo specifies a MIB module that is compliant to the SMIv2. A MIB conforming to the SMIv1 can be produced through the appropriate trans- lations. The resulting translated MIB must be semantically equivalent, except where objects or events are omitted because no translation is possible (use of Counter64). Some machine readable information in SMIv2 will be converted into textual descriptions in SMIv1 during the translation process. However, this loss of machine readable informa- tion is not considered to change the semantics of the MIB. Zorn & Aboba Standards Track [Page 2] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 6. Overview The RADIUS authentication protocol, described in [16], distinguishes between the client function and the server function. In RADIUS authen- tication, clients send Access-Requests, and servers reply with Access- Accepts, Access-Rejects, and Access-Challenges. Typically NAS devices implement the client function, and thus would be expected to implement the RADIUS authentication client MIB, while RADIUS authentication servers implement the server function, and thus would be expected to implement the RADIUS authentication server MIB. However, it is possible for a RADIUS authentication entity to perform both client and server functions. For example, a RADIUS proxy may act as a server to one or more RADIUS authentication clients, while simul- taneously acting as an authentication client to one or more authenti- cation servers. In such situations, it is expected that RADIUS enti- ties combining client and server functionality will support both the client and server MIBs. 6.1. Selected objects This MIB module contains fourteen scalars as well as a single table: (1) the RADIUS Authentication Client Table contains one row for each RADIUS authentication client that the server shares a secret with. Each entry in the RADIUS Authentication Client Table includes twelve columns presenting a view of the activity of the RADIUS authentication server. 7. Definitions RADIUS-AUTH-SERVER-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, OBJECT-IDENTITY, experimental, Counter32, Gauge32, Integer32, IpAddress FROM SNMPv2-SMI TEXTUAL-CONVENTION, DisplayString FROM SNMPv2-TC MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF; radius OBJECT-IDENTITY STATUS current DESCRIPTION "The OID assigned to RADIUS MIB work by the IANA." ::= { experimental 79 } radiusAuthentication OBJECT IDENTIFIER ::= {radius 1} radiusAuthServMIB MODULE-IDENTITY LAST-UPDATED "9811161659Z" Zorn & Aboba Standards Track [Page 3] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 ORGANIZATION "IETF RADIUS Working Group." CONTACT-INFO " Glen Zorn Microsoft One Microsoft Way Redmond, WA 98052 US Phone: +1 425 703 1559 EMail: glennz@microsoft.com" DESCRIPTION "The MIB module for entities impleenting the server side of the Remote Access Dialin User Service (RADIUS) authentication protocol." ::= { radiusAuthentication 1 } radiusAuthServMIBObjects OBJECT IDENTIFIER ::= { radiusAuthServMIB 1 } radiusAuthServ OBJECT IDENTIFIER ::= { radiusAuthServMIBObjects 1 } -- Textual conventions RadiusTime ::= TEXTUAL-CONVENTION DISPLAY-HINT "4d" STATUS current DESCRIPTION "RadiusTime values are 32-bit unsigned integers which measure time in seconds." SYNTAX Gauge32 radiusAuthServIdent OBJECT-TYPE SYNTAX DisplayString MAX-ACCESS read-only STATUS current DESCRIPTION "The implementation identification string for the RADIUS authentication server software in use on the system, for example; `FNS-2.1'" ::= {radiusAuthServ 1} radiusAuthServUpTime OBJECT-TYPE SYNTAX RadiusTime MAX-ACCESS read-only STATUS current DESCRIPTION "If the server has a persistent state (e.g., a process), this value will be the time elapsed since it started. For software without persistent state, this value will be zero." ::= {radiusAuthServ 2} radiusAuthServResetTime OBJECT-TYPE SYNTAX RadiusTime MAX-ACCESS read-only Zorn & Aboba Standards Track [Page 4] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 STATUS current DESCRIPTION "If the server has a persistent state (e.g., a process) and supports a `reset' operation (e.g., can be told to re-read configuration files), this value will be the time elapsed since the last time the name server was `reset.' For software that does not have persistence or does not support a `reset' operation, this value will be zero." ::= {radiusAuthServ 3} radiusAuthServConfigReset OBJECT-TYPE SYNTAX INTEGER { other(1), reset(2), initializing(3), running(4)} MAX-ACCESS read-write STATUS current DESCRIPTION "Status/action object to reinitialize any persistent server state. When set to reset(2), any persistent server state (such as a process) is reinitialized as if the server had just been started. This value will never be returned by a read operation. When read, one of the following values will be returned: other(1) - server in some unknown state; initializing(3) - server (re)initializing; running(4) - server currently running." ::= {radiusAuthServ 4} -- New Stats proposed by Dale E. Reed Jr (daler@iea-software.com) radiusAuthServTotalAccessRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of packets received on the authentication port since server start-up." ::= { radiusAuthServ 5} radiusAuthServTotalInvalidRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Request packets received from unknown addresses since server start-up." ::= { radiusAuthServ 6 } radiusAuthServTotalDupAccessRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current Zorn & Aboba Standards Track [Page 5] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 DESCRIPTION "The total number of duplicate RADIUS Access-Request packets received since server start-up." ::= { radiusAuthServ 7 } radiusAuthServTotalAccessAccepts OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Accept packets sent since server start-up." ::= { radiusAuthServ 8 } radiusAuthServTotalAccessRejects OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Reject packets sent since server start-up." ::= { radiusAuthServ 9 } radiusAuthServTotalAccessChallenges OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Challenge packets sent since server start-up." ::= { radiusAuthServ 10 } radiusAuthServTotalMalformedAccessRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of malformed RADIUS Access-Request packets received since server start-up. Bad authenticators and unknown types are not included as malformed Access-Requests." ::= { radiusAuthServ 11 } radiusAuthServTotalBadAuthenticators OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Authentication-Request packets which contained invalid Signature attributes received since server start-up." ::= { radiusAuthServ 12 } radiusAuthServTotalPacketsDropped OBJECT-TYPE Zorn & Aboba Standards Track [Page 6] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of incoming packets silently discarded for some reason other than malformed, bad authenticators or unknown types." ::= { radiusAuthServ 13 } radiusAuthServTotalUnknownTypes OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS packets of unknown type which were received since server start-up." ::= { radiusAuthServ 14 } -- End of new radiusAuthClientTable OBJECT-TYPE SYNTAX SEQUENCE OF RadiusAuthClientEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "The (conceptual) table listing the RADIUS authentication clients with which the server shares a secret." ::= { radiusAuthServ 15 } radiusAuthClientEntry OBJECT-TYPE SYNTAX RadiusAuthClientEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "An entry (conceptual row) representing a RADIUS authentication client with which the server shares a secret." INDEX { radiusAuthClientIndex } ::= { radiusAuthClientTable 1 } RadiusAuthClientEntry ::= SEQUENCE { radiusAuthClientIndex Integer32, radiusAuthClientAddress IpAddress, radiusAuthClientID DisplayString, radiusAuthServAccessRequests Counter32, radiusAuthServDupAccessRequests Counter32, radiusAuthServAccessAccepts Counter32, radiusAuthServAccessRejects Counter32, radiusAuthServAccessChallenges Counter32, radiusAuthServMalformedAccessRequests Counter32, radiusAuthServBadAuthenticators Counter32, radiusAuthServPacketsDropped Counter32, radiusAuthServUnknownTypes Counter32 Zorn & Aboba Standards Track [Page 7] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 } radiusAuthClientIndex OBJECT-TYPE SYNTAX Integer32 (0..MAX) MAX-ACCESS not-accessible STATUS current DESCRIPTION "A number uniquely identifying each RADIUS authentication client with which this server communicates." ::= { radiusAuthClientEntry 1 } radiusAuthClientAddress OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The NAS-IP-Address of the RADIUS authentication client referred to in this table entry." ::= { radiusAuthClientEntry 2 } radiusAuthClientID OBJECT-TYPE SYNTAX DisplayString MAX-ACCESS read-only STATUS current DESCRIPTION "The NAS-Identifier of the RADIUS authentication client referred to in this table entry. This is not necessarily the same as sysName in MIB II." ::= { radiusAuthClientEntry 3 } -- Server Counters -- -- Responses = AccessAccepts + AccessRejects + AccessChallenges -- -- Requests - DupRequests - BadAuthenticators - MalformedRequests - -- UnknownTypes - PacketsDropped - Responses = Pending -- -- Requests - DupRequests - BadAuthenticators - MalformedRequests - -- UnknownTypes - PacketsDropped = entries logged radiusAuthServAccessRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of packets received on the authentication port from this client since server start-up." ::= { radiusAuthClientEntry 4 } radiusAuthServDupAccessRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current Zorn & Aboba Standards Track [Page 8] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 DESCRIPTION "The total number of duplicate RADIUS Access-Request packets received from this client since server start-up." ::= { radiusAuthClientEntry 5 } radiusAuthServAccessAccepts OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Accept packets sent to this client since server start-up." ::= { radiusAuthClientEntry 6 } radiusAuthServAccessRejects OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Reject packets sent to this client since server start-up." ::= { radiusAuthClientEntry 7 } radiusAuthServAccessChallenges OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Access-Challenge packets sent to this client since server start-up." ::= { radiusAuthClientEntry 8 } radiusAuthServMalformedAccessRequests OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of malformed RADIUS Access-Request packets received from this client since server start-up. Bad authenticators and unknown types are not included as malformed Access-Requests." ::= { radiusAuthClientEntry 9 } radiusAuthServBadAuthenticators OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS Authentication-Request packets which contained invalid Signature attributes received from this client since server start-up." ::= { radiusAuthClientEntry 10 } radiusAuthServPacketsDropped OBJECT-TYPE Zorn & Aboba Standards Track [Page 9] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of incoming packets from this client silently discarded for some reason other than malformed, bad authenticators or unknown types." ::= { radiusAuthClientEntry 11 } radiusAuthServUnknownTypes OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of RADIUS packets of unknown type which were received from this client since authentication server start-up." ::= { radiusAuthClientEntry 12 } -- conformance information radiusAuthServMIBConformance OBJECT IDENTIFIER ::= { radiusAuthServMIB 2 } radiusAuthServMIBCompliances OBJECT IDENTIFIER ::= { radiusAuthServMIBConformance 1 } radiusAuthServMIBGroups OBJECT IDENTIFIER ::= { radiusAuthServMIBConformance 2 } -- compliance statements radiusAuthServMIBCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for authentication servers implementing the RADIUS Authentication Server MIB." MODULE -- this module MANDATORY-GROUPS { radiusAuthServMIBGroup } ::= { radiusAuthServMIBCompliances 1 } -- units of conformance radiusAuthServMIBGroup OBJECT-GROUP OBJECTS {radiusAuthServIdent, radiusAuthServUpTime, radiusAuthServResetTime, radiusAuthServConfigReset, radiusAuthServTotalAccessRequests, radiusAuthServTotalInvalidRequests, radiusAuthServTotalDupAccessRequests, Zorn & Aboba Standards Track [Page 10] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 radiusAuthServTotalAccessAccepts, radiusAuthServTotalAccessRejects, radiusAuthServTotalAccessChallenges, radiusAuthServTotalMalformedAccessRequests, radiusAuthServTotalBadAuthenticators, radiusAuthServTotalPacketsDropped, radiusAuthServTotalUnknownTypes, radiusAuthClientAddress, radiusAuthClientID, radiusAuthServAccessRequests, radiusAuthServDupAccessRequests, radiusAuthServAccessAccepts, radiusAuthServAccessRejects, radiusAuthServAccessChallenges, radiusAuthServMalformedAccessRequests, radiusAuthServBadAuthenticators, radiusAuthServPacketsDropped, radiusAuthServUnknownTypes } STATUS current DESCRIPTION "The collection of objects providing management of a RADIUS Authentication Server." ::= { radiusAuthServMIBGroups 1 } END 8. References [1] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing SNMP Management Frameworks", RFC 2271, Cabletron Sys- tems, Inc., BMC Software, Inc., IBM T. J. Watson Research, Jan- uary 1998. [2] Rose, M., and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based Internets", RFC 1155, Performance Systems International, Hughes LAN Systems, May 1990. [3] Rose, M., and K. McCloghrie, "Concise MIB Definitions", RFC 1212, Performance Systems International, Hughes LAN Systems, March 1991. [4] M. Rose, "A Convention for Defining Traps for use with the SNMP", RFC 1215, Performance Systems International, March 1991. [5] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Structure of Management Information for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1902, SNMP Research,Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc., International Network Services, January 1996. Zorn & Aboba Standards Track [Page 11] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 [6] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Textual Conventions for Version 2 of the Simple Network Management Proto- col (SNMPv2)", RFC 1903, SNMP Research, Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc., International Network Ser- vices, January 1996. [7] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Confor- mance Statements for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1904, SNMP Research, Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc., International Network Ser- vices, January 1996. [8] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple Net- work Management Protocol", RFC 1157, SNMP Research, Performance Systems International, Performance Systems International, MIT Laboratory for Computer Science, May 1990. [9] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Introduc- tion to Community-based SNMPv2", RFC 1901, SNMP Research, Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc., International Network Services, January 1996. [10] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Transport Mappings for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1906, SNMP Research, Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc., International Network Services, January 1996. [11] Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message Pro- cessing and Dispatching for the Simple Network Management Proto- col (SNMP)", RFC 2272, SNMP Research, Inc., Cabletron Systems, Inc., BMC Software, Inc., IBM T. J. Watson Research, January 1998. [12] Blumenthal, U., and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 2274, IBM T. J. Watson Research, January 1998. [13] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol Operations for Version 2 of the Simple Network Management Proto- col (SNMPv2)", RFC 1905, SNMP Research, Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc., International Network Ser- vices, January 196. [14] Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications", RFC 2273, SNMP Research, Inc., Secure Computing Corporation, Cisco Systems, January 1998 [15] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 2275, IBM T. J. Watson Research, BMC Software, Inc., Cisco Systems, Inc., January 1998 Zorn & Aboba Standards Track [Page 12] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 [16] Rigney, C., Rubens, A., Simpson W., and S. Willens, "Remote Authentication Dial In User Service (RADIUS)", RFC 2138, April 1997. [17] "Information processing systems - Open Systems Interconnection - Specification of Abstract Syntax Notation One (ASN.1)", Interna- tional Organization for Standardization, International Standard 8824, December 1987. 9. Security considerations There are a number of management objects defined in this MIB that have a MAX-ACCESS clause of read-write and/or read-create. Such objects may be considered sensitive or vulnerable in some network environ- ments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network opera- tions. There are a number of managed objects in this MIB that may contain sensitive information. These are: radiusAuthClientAddress This can be used to determine the address of the RADIUS authentication client with which the server is communicat- ing. This information could be useful in impersonating the client. radiusAuthClientID This can be used to determine the client ID of the authenti- cation client with which the server is communicating. This information could be useful in impersonating the client. It is thus important to control even GET access to these objects and possibly to even encrypt the values of these object when sending them over the network via SNMP. Not all versions of SNMP provide features for such a secure environment. SNMPv1 by itself is not a secure environment. Even if the network itself is secure (for example by using IPSec), there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB. It is recommended that the implementers consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model RFC 2274 [12] and the View-based Access Con- trol Model RFC 2275 [15] is recommended. Using these security fea- tures, customer/users can give access to the objects only to those principals (users) that have legitimate rights to GET or SET (change/create/delete) them. Zorn & Aboba Standards Track [Page 13] INTERNET-DRAFT RADIUS Authentication Server MIB 11 November 1998 10. Acknowledgments Thanks to Narendra Gidwani of Microsoft, Allan C. Rubens of MERIT, Carl Rigney of Livingston and Peter Heitman of American Internet Cor- poration for useful discussions of this problem space. 11. Authors' Addresses Bernard Aboba Microsoft Corporation One Microsoft Way Redmond, WA 98052 Phone: 425-936-6605 EMail: bernarda@microsoft.com Glen Zorn Microsoft Corporation One Microsoft Way Redmond, WA 98052 Phone: 425-703-1559 EMail: glennz@microsoft.com 12. Full Copyright Statement Copyright (C) The Internet Society (1997). All Rights Reserved. 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