Definitions of Managed Objects

for Administration of SNMP Parties

Status of this Memo

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

Abstract

This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in TCP/IP-based internets. In particular, it describes a representation of the SNMP parties defined in [8] as objects defined according to the Internet Standard SMI [1]. These definitions are consistent with the SNMP Security protocols set forth in [9].

Table of Contents

   1. The Network Management Framework ...........................    2
   2. Objects ....................................................    2
   2.1 Format of Definitions .....................................    3
   3. Overview ...................................................    3
   3.1 Structure .................................................    3
   3.2 Instance Identifiers ......................................    3
   3.3 Textual Conventions .......................................    4
   4. Definitions ................................................    4
   4.1 The SNMP Party Public Database Group ......................    9
   4.2 The SNMP Party Secrets Database Group .....................   15
   4.3 The SNMP Access Privileges Database Group .................   18
   4.4 The MIB View Database Group ...............................   21
   5. Acknowledgments ............................................   25
   6. References .................................................   25
   7. Security Considerations.....................................   26
   8. Authors' Addresses..........................................   26

1. The Network Management Framework

the Internet-standard Network Management Framework consists of three components. They are:

RFC 1155 which defines the SMI, the mechanisms used for describing and naming objects for the purpose of management. RFC 1212 defines a more concise description mechanism, which is wholly consistent with the SMI.

RFC 1156 which defines MIB-I, the core set of managed objects for the Internet suite of protocols. RFC 1213, defines MIB-II, an evolution of MIB-I based on implementation experience and new operational requirements.

RFC 1157 which defines the SNMP, the protocol used for network access to managed objects.

The Framework permits new objects to be defined for the purpose of experimentation and evaluation.

2. Objects

Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the subset of Abstract Syntax Notation One (ASN.1) [5] defined in the SMI. In particular, each object has a name, a syntax, and an encoding. The name is an object identifier, an administratively assigned name, which specifies an object type. The object type together with an object instance serves to uniquely identify a specific instantiation of the object. For human convenience, we often use a textual string, termed the OBJECT DESCRIPTOR, to also refer to the object type.

The syntax of an object type defines the abstract data structure corresponding to that object type. The ASN.1 language is used for this purpose. However, the SMI [1] purposely restricts the ASN.1 constructs which may be used. These restrictions are explicitly made for simplicity.

The encoding of an object type is simply how that object type is represented using the object type's syntax. Implicitly tied to the notion of an object type's syntax and encoding is how the object type is represented when being transmitted on the network.

The SMI specifies the use of the basic encoding rules of ASN.1 [6], subject to the additional requirements imposed by the SNMP.

2.1. Format of Definitions

Section 4 contains the specification of all object types contained in this MIB module. The object types are defined using the conventions defined in the SMI, as amended by the extensions specified in [7].

3. Overview

3.1. Structure

This MIB contains the definitions for four tables, a number of OBJECT IDENTIFIER assignments, and some conventions for initial use with some of the assignments. The four tables are the SNMP Party Public database, the SNMP Party Secrets database, the SNMP Access Control database, and the SNMP Views database.

The SNMP Party Public database and the SNMP Party Secrets database are defined as separate tables specifically for the purpose of positioning them in different parts of the MIB tree namespace. In particular, the SNMP Party Secrets database contains secret information, for which security demands that access to it be limited to parties which use both authentication and privacy. It is therefore positioned in a separate branch of the MIB tree so as to provide for the easiest means of accommodating the required limitation.

In contrast, the SNMP Party Public database contains public information about SNMP parties. In particular, it contains the parties' clocks which need to be read-able (but not write-able) by unauthenticated queries, since an unauthenticated query of a party's clock is the first step of the procedure to re-establish clock synchronization (see [9]).

The objects in this MIB are organized into four groups. All four of the groups are mandatory for those SNMP implementations that realize the security framework and mechanisms defined in [8] and [9].

3.2. Instance Identifiers

In all four of the tables in this MIB, the object instances are identified by values which have an underlying syntax of OBJECT IDENTIFIER. For the Party Public database and the Party Secrets database, the index variable is the party identifier. For the Access Control database and the Views database, two index variables are defined, both of which have a syntax of OBJECT IDENTIFIER. (See the INDEX clauses in the MIB definitions below for the specific variables.)

According to RFC 1212 [7], section 4.1.6, the syntax of the object(s) specified in an INDEX clause indicates how to form the instance- identifier. In particular, for each index object which is object identifier-valued, its contribution to the instance identifier is:

`n+1' sub-identifiers, where `n' is the number of sub-identifiers in the value (the first sub-identifier is `n' itself, following this, each sub-identifier in the value is copied).

3.3. Textual Conventions

The datatypes, Party, Clock, and TAddress, are used as textual conventions in this document. These textual conventions have NO effect on either the syntax nor the semantics of any managed object. Objects defined using these conventions are always encoded by means of the rules that define their primitive type. Hence, no changes to the SMI or the SNMP are necessary to accommodate these textual conventions which are adopted merely for the convenience of readers.

4. Definitions

RFC1353-MIB DEFINITIONS ::= BEGIN

IMPORTS

                  system, mib, private, internet    FROM RFC1155-SMI
                  OBJECT-TYPE                       FROM RFC-1212;

snmpParties OBJECT IDENTIFIER ::= { mib-2 20 }

partyAdmin OBJECT IDENTIFIER ::= { snmpParties 1 }

partyPublic OBJECT IDENTIFIER ::= { snmpParties 2 }

          snmpSecrets     OBJECT IDENTIFIER ::= { mib-2 21 }
          partyPrivate    OBJECT IDENTIFIER ::= { snmpSecrets 1 }
          partyAccess     OBJECT IDENTIFIER ::= { snmpSecrets 2 }
          partyViews      OBJECT IDENTIFIER ::= { snmpSecrets 3 }
          
          --                  Textual Conventions
          
          --    A textual convention denoting a SNMP party identifier:

Party ::= OBJECT IDENTIFIER

          --    A party's authentication clock - a non-negative integer
          -- which is incremented as specified/allowed by the party's
          -- Authentication Protocol.
          --    For noAuth, a party's authentication clock is unused and
          -- its value is undefined.
          --    For md5AuthProtocol, a party's authentication clock is a
          -- relative clock with 1-second granularity.
          
          Clock ::= INTEGER (0..2147483647)
          
          --    A textual convention denoting a transport service
          -- address.
          --    For rfc1351Domain, a TAddress is 6 octets long,
          -- the initial 4 octets containing the IP-address in
          -- network-byte order and the last 2 containing the
          -- UDP port in network-byte order.

TAddress ::= OCTET STRING

          --- Definitions of Security Protocols

partyProtocols

              OBJECT IDENTIFIER ::= { partyAdmin 1 }
          
          noAuth                  -- The protocol without authentication
              OBJECT IDENTIFIER ::= { partyProtocols 1 }

noPriv -- The protocol without privacy

OBJECT IDENTIFIER ::= { partyProtocols 3 }

desPrivProtocol -- The DES Privacy Protocol

OBJECT IDENTIFIER ::= { partyProtocols 4 }

          md5AuthProtocol         -- The MD5 Authentication Protocol
              OBJECT IDENTIFIER ::= { partyProtocols 5 }
          
          --- definitions of Transport Domains

transportDomains

              OBJECT IDENTIFIER ::= { partyAdmin 2 }
          
          rfc1351Domain --- RFC-1351 (SNMP over UDP, using SNMP Parties)
              OBJECT IDENTIFIER ::= { transportDomains 1 }
          
          --- definitions of Proxy Domains

proxyDomains

              OBJECT IDENTIFIER ::= { partyAdmin 3 }
          
          noProxy                --- Local operation
              OBJECT IDENTIFIER ::= { proxyDomains 1 }
          
          ---    Definition of Initial Party Identifiers

-- When devices are installed, they need to be configured -- with an initial set of SNMP parties. The configuration -- of SNMP parties requires (among other things) the
-- assignment of several OBJECT IDENTIFIERs. Any local -- network administration can obtain the delegated
-- authority necessary to assign its own OBJECT
-- IDENTIFIERs. However, to provide for those
-- administrations who have not obtained the necessary -- authority, this document allocates a branch of the
-- naming tree for use with the following conventions.

initialPartyId

              OBJECT IDENTIFIER ::= { partyAdmin 4 }

-- Note these are identified as "initial" party identifiers -- since these allow secure SNMP communication to proceed, -- thereby allowing further SNMP parties to be configured -- through use of the SNMP itself.

-- The following definitions identify a party identifier, -- and specify the initial values of various object
-- instances indexed by that identifier. In addition, -- the initial MIB view and access control parameters
-- assigned, by convention, to these parties are identified.

          --    Party Identifiers for use as initial SNMP parties
          --       at IP address  a.b.c.d
          
          -- partyIdentity            = { initialPartyId a b c d 1 }
          -- partyTDomain             = { rfc1351Domain }
          -- partyTAddress            = a.b.c.d, 161
          -- partyProxyFor            = { noProxy }
          -- partyAuthProtocol        = { noAuth }
          -- partyAuthClock           = 0
          -- partySecretsAuthPrivate  = ''h    (the empty string)
          -- partyAuthPublic          = ''h    (the empty string)
          -- partyAuthLifetime        = 0

-- partyPrivProtocol = { noPriv }

-- partySecretsPrivPrivate = ''h (the empty string)

-- partyPrivPublic = ''h (the empty string)

          -- partyIdentity            = { initialPartyId a b c d 2 }
          -- partyTDomain             = { rfc1351Domain }
          -- partyTAddress            = assigned by local administration
          -- partyProxyFor            = { noProxy }
          -- partyAuthProtocol        = { noAuth }
          -- partyAuthClock           = 0
          -- partySecretsAuthPrivate  = ''h    (the empty string)
          -- partyAuthPublic          = ''h    (the empty string)
          -- partyAuthLifetime        = 0
          -- partyPrivProtocol        = { noPriv }
          -- partySecretsPrivPrivate  = ''h    (the empty string)
          -- partyPrivPublic          = ''h    (the empty string)
          
          -- partyIdentity            = { initialPartyId a b c d 3 }
          -- partyTDomain             = { rfc1351Domain }
          -- partyTAddress            = a.b.c.d, 161
          -- partyProxyFor            = { noProxy }
          -- partyAuthProtocol        = { md5AuthProtocol }
          -- partyAuthClock           = 0
          -- partySecretsAuthPrivate  = assigned by local administration
          -- partyAuthPublic          = ''h    (the empty string)
          -- partyAuthLifetime        = 300
          -- partyPrivProtocol        = { noPriv }
          -- partySecretsPrivPrivate  = ''h    (the empty string)
          -- partyPrivPublic          = ''h    (the empty string)
          
          -- partyIdentity            = { initialPartyId a b c d 4 }
          -- partyTDomain             = { rfc1351Domain }
          -- partyTAddress            = assigned by local administration
          -- partyProxyFor            = { noProxy }
          -- partyAuthProtocol        = { md5AuthProtocol }
          -- partyAuthClock           = 0
          -- partySecretsAuthPrivate  = assigned by local administration
          -- partyAuthPublic          = ''h    (the empty string)
          -- partyAuthLifetime        = 300
          -- partyPrivProtocol        = { noPriv }
          -- partySecretsPrivPrivate  = ''h    (the empty string)
          -- partyPrivPublic          = ''h    (the empty string)
          
          -- partyIdentity            = { initialPartyId a b c d 5 }
          -- partyTDomain             = { rfc1351Domain }
          -- partyTAddress            = a.b.c.d, 161
          -- partyProxyFor            = { noProxy }
          -- partyAuthProtocol        = { md5AuthProtocol }
          -- partyAuthClock           = 0
          -- partySecretsAuthPrivate  = assigned by local administration
          -- partyAuthPublic          = ''h    (the empty string)
          -- partyAuthLifetime        = 300
          -- partyPrivProtocol        = { desPrivProtocol }
          -- partySecretsPrivPrivate  = assigned by local administration
          -- partyPrivPublic          = ''h    (the empty string)
          
          -- partyIdentity            = { initialPartyId a b c d 6 }
          -- partyTDomain             = { rfc1351Domain }
          -- partyTAddress            = assigned by local administration
          -- partyProxyFor            = { noProxy }
          -- partyAuthProtocol        = { md5AuthProtocol }
          -- partyAuthClock           = 0
          -- partySecretsAuthPrivate  = assigned by local administration
          -- partyAuthPublic          = ''h    (the empty string)
          -- partyAuthLifetime        = 300
          -- partyPrivProtocol        = { desPrivProtocol }
          -- partySecretsPrivPrivate  = assigned by local administration
          -- partyPrivPublic          = ''h   (the empty string)

-- The initial access control parameters assigned, by
-- convention, to these parties are:

-- aclTarget = { initialPartyId a b c d 1 }

-- aclSubject = { initialPartyId a b c d 2 }

-- aclPrivileges = 3 (Get & Get-Next)

-- aclTarget = { initialPartyId a b c d 2 }

-- aclSubject = { initialPartyId a b c d 1 }

-- aclPrivileges = 20 (GetResponse & Trap)

-- aclTarget = { initialPartyId a b c d 3 }

-- aclSubject = { initialPartyId a b c d 4 }

-- aclPrivileges = 11 (Get, Get-Next & Set)

-- aclTarget = { initialPartyId a b c d 4 }

-- aclSubject = { initialPartyId a b c d 3 }

-- aclPrivileges = 20 (GetResponse & Trap)

-- aclTarget = { initialPartyId a b c d 5 }

-- aclSubject = { initialPartyId a b c d 6 }

-- aclPrivileges = 11 (Get, Get-Next & Set)

-- aclTarget = { initialPartyId a b c d 6 }

-- aclSubject = { initialPartyId a b c d 5 }

-- aclPrivileges = 20 (GetResponse & Trap)

-- The initial MIB views assigned, by convention, to
-- these parties are:

          -- viewParty    = { initialPartyId a b c d 1 }
          -- viewSubtree  = { system }
          -- viewStatus   = { included }
          -- viewMask     = { ''h }
          
          -- viewParty    = { initialPartyId a b c d 1 }
          -- viewSubtree  = { snmpParties }
          -- viewStatus   = { included }
          -- viewMask     = { ''h }
          
          -- viewParty    = { initialPartyId a b c d 3 }
          -- viewSubtree  = { internet }
          -- viewStatus   = { included }
          -- viewMask     = { ''h }
          
          -- viewParty    = { initialPartyId a b c d 3 }
          -- viewSubtree  = { partyPrivate }
          -- viewStatus   = { excluded }
          -- viewMask     = { ''h }
          
          -- viewParty    = { initialPartyId a b c d 5 }
          -- viewSubtree  = { internet }
          -- viewStatus   = { included }
          -- viewMask     = { ''h }
          
          --   The SNMP Party Public Database Group
          --
          -- The non-secret party information.
          --
          -- Implementation of the objects in this group is mandatory.

partyTable OBJECT-TYPE

              SYNTAX  SEQUENCE OF PartyEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "The SNMP Party Public database.

An agent must ensure that there is, at all times, a one-to-one correspondence between entries in this table and entries in the partySecretsTable.

The creation/deletion of instances in this table via SNMP Set-Requests is not allowed. Instead, entries in this table are created/deleted as a side-effect of the creation/deletion of corresponding entries in the partySecretsTable.

                      Thus, a SNMP Set-Request whose varbinds contain a
                      reference to a non-existent instance of a
                      partyTable object, but no reference to the
                      corresponding instance of a partySecretsTable
                      object, will be rejected."
          ::= { partyPublic 1 }

partyEntry OBJECT-TYPE

              SYNTAX  PartyEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "Locally held non-secret information about a
                      particular SNMP party, which is available for
                      access by network management.  Note that this does
                      not include all locally held information about a
                      party.  In particular, it does not include the
                      'last-timestamp' (i.e., the timestamp of the last
                      authentic message received) or the 'nonce'
                      values."
              INDEX  { partyIdentity }
              ::= { partyTable 1 }

PartyEntry ::=

SEQUENCE {

                  partyIdentity
                      Party,
                  partyTDomain
                      OBJECT IDENTIFIER,
                  partyTAddress
                      TAddress,
                  partyProxyFor
                      Party,
                  partyAuthProtocol
                      OBJECT IDENTIFIER,
                  partyAuthClock
                      Clock,
                  partyAuthPublic
                      OCTET STRING,
                  partyAuthLifetime
                      INTEGER,
                  partyPrivProtocol
                      OBJECT IDENTIFIER,
                  partyPrivPublic
              
                      OCTET STRING,
                  partyMaxMessageSize
                      INTEGER,
                  partyStatus
                      INTEGER
              }
          
          partyIdentity  OBJECT-TYPE
              SYNTAX  Party
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "A party identifier uniquely identifying a
                      particular SNMP party."
              ::= { partyEntry 1 }
          
          partyTDomain  OBJECT-TYPE
              SYNTAX  OBJECT IDENTIFIER
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "Indicates the kind of transport service by which
                      the party receives network management traffic. An
                      example of a transport domain is 'rfc1351Domain'
                      (SNMP over UDP)."
              DEFVAL  { rfc1351Domain }
              ::= { partyEntry 2 }
          
          partyTAddress  OBJECT-TYPE
              SYNTAX  TAddress
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The transport service address by which the party
                      receives network management traffic, formatted
                      according to the corresponding value of
                      partyTDomain.  For rfc1351Domain, partyTAddress is
                      formatted as a 4-octet IP Address concatenated
                      with a 2-octet UDP port number."
              DEFVAL  { '000000000000'h }
              ::= { partyEntry 3 }

partyProxyFor OBJECT-TYPE

              SYNTAX  Party
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The identity of a second SNMP party or other
              
                      management entity with which interaction may be
                      necessary to satisfy received management requests.
                      In this context, the distinguished value { noProxy
                      } signifies that the party responds to received
                      management requests by entirely local mechanisms."
              DEFVAL  { noProxy }
              ::= { partyEntry 4 }

partyAuthProtocol OBJECT-TYPE

              SYNTAX  OBJECT IDENTIFIER
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The authentication protocol by which all messages
                      generated by the party are authenticated as to
                      origin and integrity.  In this context, the value
                      { noAuth } signifies that messages generated by
                      the party are not authenticated."
              DEFVAL  { md5AuthProtocol }
              ::= { partyEntry 5 }

partyAuthClock OBJECT-TYPE

              SYNTAX  Clock
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The authentication clock which represents the
                      local notion of the current time specific to the
                      party.  This value must not be decremented unless
                      the party's secret information is changed
                      simultaneously, at which time the party's nonce
                      and last-timestamp values must also be reset to
                      zero, and the new value of the clock,
                      respectively."
              DEFVAL  { 0 }
              ::= { partyEntry 6 }

partyAuthPublic OBJECT-TYPE

              SYNTAX  OCTET STRING -- for md5AuthProtocol: (SIZE (0..16))
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "A publically-readable value for the party.

Depending on the party's authentication protocol, this value may be needed to support the party's authentication protocol. Alternatively, it may be used by a manager during the procedure for altering secret information about a party. (For example, by altering the value of an instance of this object in the same SNMP Set-Request used to update an instance of partyAuthPrivate, a subsequent Get-Request can determine if the Set- Request was successful in the event that no response to the Set-Request is received, see RFC 1352.)

                      The length of the value is dependent on the
                      party's authentication protocol.  If not used by
                      the authentication protocol, it is recommended
                      that agents support values of any length up to and
                      including the length of the corresponding
                      partyAuthPrivate object."
              DEFVAL  { ''h }      -- the empty string
              ::= { partyEntry 7 }

partyAuthLifetime OBJECT-TYPE

              SYNTAX  INTEGER (0..2147483647)
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The lifetime (in units of seconds) which
                      represents an administrative upper bound on
                      acceptable delivery delay for protocol messages
                      generated by the party."
              DEFVAL  { 300 }
              ::= { partyEntry 8 }

partyPrivProtocol OBJECT-TYPE

              SYNTAX  OBJECT IDENTIFIER
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The privacy protocol by which all protocol
                      messages received by the party are protected from
                      disclosure.  In this context, the value { noPriv }
                      signifies that messages received by the party are
                      not protected."
              DEFVAL  { noPriv }
              ::= { partyEntry 9 }

partyPrivPublic OBJECT-TYPE

              SYNTAX  OCTET STRING -- for desPrivProtocol: (SIZE (0..16))
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION

"A publically-readable value for the party.

Depending on the party's privacy protocol, this value may be needed to support the party's privacy protocol. Alternatively, it may be used by a manager as a part of its procedure for altering secret information about a party. (For example, by altering the value of an instance of this object in the same SNMP Set-Request used to update an instance of partyPrivPrivate, a subsequent Get-Request can determine if the Set-Request was successful in the event that no response to the Set-Request is received, see RFC 1352.)

                      The length of the value is dependent on the
                      party's privacy protocol.  If not used by the
                      privacy protocol, it is recommended that agents
                      support values of any length up to and including
                      the length of the corresponding partyPrivPrivate
                      object."
              DEFVAL  { ''h }     -- the empty string
              ::= { partyEntry 10 }

partyMaxMessageSize OBJECT-TYPE

              SYNTAX  INTEGER (484..65507)
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The maximum length in octets of a SNMP message
                      which this party will accept.  For parties which
                      execute at an agent, the agent initializes this
                      object to the maximum length supported by the
                      agent, and does not let the object be set to any
                      larger value.  For parties which do not execute at
                      the agent, the agent must allow the manager to set
                      this object to any legal value, even if it is
                      larger than the agent can generate."
              DEFVAL  { 484 }
              ::= { partyEntry 11 }

partyStatus OBJECT-TYPE

              SYNTAX  INTEGER  { valid(1), invalid(2) }
              ACCESS  read-only
              STATUS  mandatory
              DESCRIPTION
                      "The status of the locally-held information on a
                      particular SNMP party.

The instance of this object for a particular party and the instance of partySecretsStatus for the same party always have the same value.

                      This object will typically provide unrestricted
                      read-only access to the status of parties.  In
                      contrast, partySecretsStatus will typically
                      provide restricted read-write access to the status
                      of parties."
              ::= { partyEntry 12 }
          
          --   The SNMP Party Secrets Database Group

-- The secret party information
--
-- Implementation of the objects in this group is mandatory.

          partySecretsTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF PartySecretsEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "The SNMP Party Secrets database."
          ::= { partyPrivate 1 }

partySecretsEntry OBJECT-TYPE

              SYNTAX  PartySecretsEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "Locally held secret information about a
                      particular SNMP party, which is available for
                      access by network management.
              
                      When a SNMP Set-Request is used to update the
                      values of instances of objects in this table, it
                      is recommended that the same SNMP Set-Request also
                      alter the value of a non-secret object instance
                      (e.g., an instance of partyAuthPublic or
                      partyPrivPublic).  This allows a Get-Request of
                      that non-secret object instance to determine if
                      the Set-Request was successful in the event that
                      no response which matches the Set-Request is
                      received, see RFC 1352."
              INDEX  { partySecretsIdentity }
              ::= { partySecretsTable 1 }

PartySecretsEntry ::=

              SEQUENCE {
                  partySecretsIdentity
                      Party,
                  partySecretsAuthPrivate
                      OCTET STRING,
                  partySecretsPrivPrivate
                      OCTET STRING,
                  partySecretsStatus
                      INTEGER
              }
          
          partySecretsIdentity  OBJECT-TYPE
              SYNTAX  Party
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "A party identifier uniquely identifying a
                      particular SNMP party."
              ::= { partySecretsEntry 1 }

partySecretsAuthPrivate OBJECT-TYPE

              SYNTAX  OCTET STRING   -- for md5AuthProtocol: (SIZE (16))
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "An encoding of the party's private authentication
                      key which may be needed to support the
                      authentication protocol.  Although the value of
                      this variable may be altered by a management
                      operation (e.g., a SNMP Set-Request), its value
                      can never be retrieved by a management operation:
                      when read, the value of this variable is the zero
                      length OCTET STRING.

The private authentication key is NOT directly represented by the value of this variable, but rather it is represented according to an encoding. This encoding is the bitwise exclusive-OR of the old key with the new key, i.e., of the old private authentication key (prior to the alteration) with the new private authentication key (after the alteration). Thus, when processing a received protocol Set operation, the new private authentication key is obtained from the value of this variable as the result of a bitwise exclusive-OR of the variable's value and the old private authentication key. In calculating the

                      exclusive-OR, if the old key is shorter than the
                      new key, zero-valued padding is appended to the
                      old key.  If no value for the old key exists, a
                      zero-length OCTET STRING is used in the
                      calculation."
              DEFVAL  { ''h }     -- the empty string
              ::= { partySecretsEntry 2 }

partySecretsPrivPrivate OBJECT-TYPE

              SYNTAX  OCTET STRING   -- for desPrivProtocol: (SIZE (16))
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "An encoding of the party's private encryption key
                      which may be needed to support the privacy
                      protocol.  Although the value of this variable may
                      be altered by a management operation (e.g., a SNMP
                      Set-Request), its value can never be retrieved by
                      a management operation: when read, the value of
                      this variable is the zero length OCTET STRING.
              
                      The private encryption key is NOT directly
                      represented by the value of this variable, but
                      rather it is represented according to an encoding.
                      This encoding is the bitwise exclusive-OR of the
                      old key with the new key, i.e., of the old private
                      encryption key (prior to the alteration) with the
                      new private encryption key (after the alteration).
                      Thus, when processing a received protocol Set
                      operation, the new private encryption key is
                      obtained from the value of this variable as the
                      result of a bitwise exclusive-OR of the variable's
                      value and the old private encryption key.  In
                      calculating the exclusive-OR, if the old key is
                      shorter than the new key, zero-valued padding is
                      appended to the old key.  If no value for the old
                      key exists, a zero-length OCTET STRING is used in
                      the calculation."
              DEFVAL  { ''h }     -- the empty string
              ::= { partySecretsEntry 3 }

partySecretsStatus OBJECT-TYPE

              SYNTAX  INTEGER  { valid(1), invalid(2) }
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The status of the locally-held information on a
                      particular SNMP party.

Setting an instance of this object to the value 'valid(1)' has the effect of ensuring that valid local knowledge exists for the corresponding party. For valid local knowledge to exist, there must be corresponding instances of each object in this table and in the partyTable. Thus, the creation of instances in the partyTable (but not in the aclTable or viewTable) occurs as a direct result of the creation of instances in this table.

Setting an instance of this object to the value 'invalid(2)' has the effect of invalidating all local knowledge of the corresponding party, including the invalidating of any/all entries in the partyTable, the partySecretsTable, the aclTable, and the viewTable which reference said party.

                      It is an implementation-specific matter as to
                      whether the agent removes an invalidated entry
                      from the table.  Accordingly, management stations
                      must be prepared to receive from agents tabular
                      information corresponding to entries not currently
                      in use.  Proper interpretation of such entries
                      requires examination of the relevant
                      partySecretsStatus object."
              DEFVAL  { valid }
              ::= { partySecretsEntry 4 }

-- The SNMP Access Privileges Database Group

-- This group of objects allows the SNMP itself to be used to -- configure new SNMP parties, or to manipulate the access -- privileges of existing parties.
--
-- Implementation of the objects in this group is mandatory.

          aclTable OBJECT-TYPE
              SYNTAX  SEQUENCE OF AclEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "The access privileges database."
          ::= { partyAccess 1 }

aclEntry OBJECT-TYPE

              SYNTAX  AclEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "The access privileges for a particular requesting
                      SNMP party in accessing a particular target SNMP
                      party."
              INDEX  { aclTarget, aclSubject }
              ::= { aclTable 1 }

AclEntry ::=

              SEQUENCE {
                  aclTarget
                      Party,
                  aclSubject
                      Party,
                  aclPrivileges
                      INTEGER,
                  aclStatus
                      INTEGER
              }

aclTarget OBJECT-TYPE

              SYNTAX  Party
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The target SNMP party whose performance of
                      management operations is constrained by this set
                      of access privileges."
              ::= { aclEntry 1 }

aclSubject OBJECT-TYPE

              SYNTAX  Party
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The subject SNMP party whose requests for
                      management operations to be performed is
                      constrained by this set of access privileges."
              ::= { aclEntry 2 }

aclPrivileges OBJECT-TYPE

              SYNTAX  INTEGER (0..31)
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION

"The access privileges which govern what management operations a particular target party may perform when requested by a particular subject party. These privileges are specified as a sum of values, where each value specifies a SNMP PDU type by which the subject party may request a permitted operation. The value for a particular PDU type is computed as 2 raised to the value of the ASN.1 context-specific tag for the appropriate SNMP PDU type. The values (for the tags defined in RFC 1157) are defined in RFC 1351 as:

                       Get         :   1
                       GetNext     :   2
                       GetResponse :   4
                       Set         :   8
                       Trap        :  16
              
                      The null set is represented by the value zero."
              DEFVAL  { 3 }      -- Get & Get-Next
              ::= { aclEntry 3 }

aclStatus OBJECT-TYPE

              SYNTAX  INTEGER  { valid(1), invalid(2) }
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The status of the access privileges for a
                      particular requesting SNMP party in accessing a
                      particular target SNMP party.  Setting an instance
                      of this object to the value 'invalid(2)' has the
                      effect of invalidating the corresponding access
                      privileges.
              
                      It is an implementation-specific matter as to
                      whether the agent removes an invalidated entry
                      from the table.  Accordingly, management stations
                      must be prepared to receive from agents tabular
                      information corresponding to entries not currently
                      in use.  Proper interpretation of such entries
                      requires examination of the relevant aclStatus
                      object."
              DEFVAL  { valid }
              ::= { aclEntry 4 }
          
          --   The MIB View Database Group

-- This group of objects allows the SNMP itself to be used to -- configure new SNMP parties, or to manipulate the MIB -- MIB views of existing parties.
--
-- Implementation of the objects in this group is mandatory.

viewTable OBJECT-TYPE

              SYNTAX  SEQUENCE OF ViewEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "The table contained in the local database which
                      defines local MIB views.  Each SNMP party has a
                      single MIB view which is defined by two
                      collections of view subtrees: the included view
                      subtrees, and the excluded view subtrees.  Every
                      such subtree, both included and excluded, is
                      defined in this table.

To determine if a particular object instance is in a particular SNMP party's MIB view, compare the object instance's Object Identifier with each entry (for this party) in this table. If none match, then the object instance is not in the MIB view. If one or more match, then the object instance is included in, or excluded from, the MIB view according to the value of viewStatus in the entry whose value of viewSubtree has the most sub-identifiers. If multiple entries match and have the same number of sub-identifiers, then the lexicographically greatest instance of viewStatus determines the inclusion or exclusion.

An object instance's Object Identifier X matches an entry in this table when the number of sub- identifiers in X is at least as many as in the value of viewSubtree for the entry, and each sub- identifier in the value of viewSubtree matches its corresponding sub-identifier in X. Two sub- identifiers match either if the corresponding bit of viewMask is zero (the 'wild card' value), or if they are equal.

Due to this 'wild card' capability, we introduce the term, a 'family' of view subtrees, to refer to

                      the set of subtrees defined by a particular
                      combination of values of viewSubtree and viewMask.
                      In the case where no 'wild card' is defined in
                      viewMask, the family of view subtrees reduces to a
                      single view subtree."
          ::= { partyViews 1 }

viewEntry OBJECT-TYPE

              SYNTAX  ViewEntry
              ACCESS  not-accessible
              STATUS  mandatory
              DESCRIPTION
                      "Information on a particular family of view
                      subtrees included in or excluded from a particular
                      SNMP party's MIB view."
              INDEX  { viewParty, viewSubtree }
              ::= { viewTable 1 }

ViewEntry ::=

              SEQUENCE {
                  viewParty
                      Party,
                  viewSubtree
                      OBJECT IDENTIFIER,
                  viewStatus
                      INTEGER,
                  viewMask
                      OCTET STRING
              }
          
          viewParty  OBJECT-TYPE
              SYNTAX  Party
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The SNMP party whose single MIB view includes or
                      excludes a particular family of view subtrees."
              ::= { viewEntry 1 }

viewSubtree OBJECT-TYPE

              SYNTAX  OBJECT IDENTIFIER
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The view subtree which, in combination with the
                      corresponding instance of viewMask, defines a
                      family of view subtrees.  This family is included
                      in, or excluded from the particular SNMP party's
              
                      MIB view, according to the value of the
                      corresponding instance of viewStatus."
              ::= { viewEntry 2 }

viewStatus OBJECT-TYPE

              SYNTAX  INTEGER  {
                          included(1),
                          excluded(2),
                          invalid(3)
                      }
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The status of a particular family of view
                      subtrees within the particular SNMP party's MIB
                      view.  The value 'included(1)' indicates that the
                      corresponding instances of viewSubtree and
                      viewMask define a family of view subtrees included
                      in the MIB view.  The  value 'excluded(2)'
                      indicates that the corresponding instances of
                      viewSubtree and viewMask define a family of view
                      subtrees excluded from the MIB view.

Setting an instance of this object to the value 'invalid(3)' has the effect of invalidating the presence or absence of the corresponding family of view subtrees in the corresponding SNMP party's MIB view.

                      It is an implementation-specific matter as to
                      whether the agent removes an invalidated entry
                      from the table.  Accordingly, management stations
                      must be prepared to receive from agents tabular
                      information corresponding to entries not currently
                      in use.  Proper interpretation of such entries
                      requires examination of the relevant viewStatus
                      object."
              DEFVAL  { included }
              ::= { viewEntry 3 }
          
          viewMask  OBJECT-TYPE
              SYNTAX  OCTET STRING (SIZE (0..16))
              ACCESS  read-write
              STATUS  mandatory
              DESCRIPTION
                      "The bit mask which, in combination with the
                      corresponding instance of viewSubtree, defines a
                      family of view subtrees.

Each bit of this bit mask corresponds to a sub- identifier of viewSubtree, with the most significant bit of the i-th octet of this octet string value (extended if necessary, see below) corresponding to the (8*i - 7)-th sub-identifier, and the least significant bit of the i-th octet of this octet string corresponding to the (8*i)-th sub-identifier, where i is in the range 1 through 16.

Each bit of this bit mask specifies whether or not the corresponding sub-identifiers must match when determining if an Object Identifier is in this family of view subtrees; a '1' indicates that an exact match must occur; a '0' indicates 'wild card', i.e., any sub-identifier value matches.

Thus, the Object Identifier X of an object instance is contained in a family of view subtrees if the following criteria are met:

for each sub-identifier of the value of viewSubtree, either:

the i-th bit of viewMask is 0, or

the i-th sub-identifier of X is equal to the i-th sub-identifier of the value of viewSubtree.

If the value of this bit mask is M bits long and there are more than M sub-identifiers in the corresponding instance of viewSubtree, then the bit mask is extended with 1's to be the required length.

                      Note that when the value of this object is the
                      zero-length string, this extension rule results in
                      a mask of all-1's being used (i.e., no 'wild
                      card'), and the family of view subtrees is the one
                      view subtree uniquely identified by the
                      corresponding instance of viewSubtree."
              DEFVAL  { ''h }
              ::= { viewEntry 4 }
          
          END

5. Acknowledgments

This document was produced on behalf of the SNMP Security Working Group of the Internet Engineering Task Force. The authors wish to thank the members of the working group, and others who contributed to this effort.

6. References

   [1] 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.
   
   [2] McCloghrie, K., and M. Rose, "Management Information Base for
       Network Management of TCP/IP-based Internets", RFC 1156, Hughes
       LAN Systems and Performance Systems International, May 1990.
   
   [3] Case, J., M. Fedor, M. Schoffstall, and J. Davin, The Simple
       Network Management Protocol", RFC 1157, University of Tennessee
       at Knoxville, Performance Systems International, Performance
       Systems International, and the MIT Laboratory for Computer
       Science, May 1990.
   
   [4] McCloghrie K., and M. Rose, Editors, "Management Information Base
       for Network Management of TCP/IP-based internets", RFC 1213,
       Performance Systems International, March 1991.
   
   [5] Information processing systems - Open Systems Interconnection -
       Specification of Abstract Syntax Notation One (ASN.1),
       International Organization for Standardization, International
       Standard 8824, December 1987.
   
   [6] Information processing systems - Open Systems Interconnection -
       Specification of Basic Encoding Rules for Abstract Notation One
       (ASN.1), International Organization for Standardization,
       International Standard 8825, December 1987.
   
   [7] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
       RFC 1212, Performance Systems International, Hughes LAN Systems,
       March 1991.
   
   [8] Davin, J., Galvin, J., and K. McCloghrie, "SNMP Administrative
       Model", RFC 1351, MIT Laboratory for Computer Science, Trusted
       Information Systems, Inc., Hughes LAN Systems, Inc., July 1992.
   
   [9] Galvin, J., McCloghrie, K., and J. Davin, "SNMP Security
       Protocols", RFC 1352, Trusted Information Systems, Inc., Hughes
       LAN Systems, Inc., MIT Laboratory for Computer Science, July

Security Considerstions

Security issues are discussed in section 3.1. and in RFCs 1351 and 1352.

Authors' Addresses

Keith McCloghrie
Hughes LAN Systems, Inc.
Mountain View, CA 94043

   Phone:  (415) 966-7934
   EMail:  kzm@hls.com

James R. Davin
MIT Laboratory for Computer Science
545 Technology Square
Cambridge, MA 02139

   Phone:  (617) 253-6020
   EMail:  jrd@ptt.lcs.mit.edu

James M. Galvin
Trusted Information Systems, Inc.
3060 Washington Road, Route 97
Glenwood, MD 21738

   Phone:  (301) 854-6889
   EMail:  galvin@tis.com