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ENTERASYS-ENCR-8021X-REKEYING-MIB by vendor Enterasys Networks


The SNMP protocol is used to for conveying information and commands between agents and managing entities. SNMP uses the User Datagram Protocol (UDP) as the transport protocol for passing data between managers and agents. The reasons for using UDP for SNMP are, firstly it has low overheads in comparison to TCP, which uses a 3-way hand shake for connection. Secondly, in congested networks, SNMP over TCP is a bad idea because TCP in order to maintain reliability will flood the network with retransmissions.

Management information (MIB) is represented as a collection of managed objects. These objects together form a virtual information base called MIB. An agent may implement many MIBs, but all agents must implement a particular MIB called MIB-II [16]. This standard defines variables for things such as interface statistics (interface speeds, MTU, octets sent, octets received, etc.) as well as various other things pertaining to the system itself (system location, system contact, etc.). The main goal of MIB-II is to provide general TCP/IP management information.

Use ActiveXperts Network Monitor 2019 to import vendor-specific MIB files, inclusing ENTERASYS-ENCR-8021X-REKEYING-MIB.

Vendor: Enterasys Networks
Mib: ENTERASYS-ENCR-8021X-REKEYING-MIB  [download]  [view objects]
Tool: ActiveXperts Network Monitor 2019 [download]    (ships with advanced SNMP/MIB tools)

--  enterasys-encr-8021x-rekeying-mib.txt
--  Part Number: <TBD>

--  This module provides authoritative definitions for Enterasys 
--  Networks' encrypted IEEE 802.1x rapid rekeying MIB.

--  This module will be extended, as needed.

--  Enterasys Networks reserves the right to make changes in this
--  specification and other information contained in this document
--  without prior notice.  The reader should consult Enterasys Networks
--  to determine whether any such changes have been made.
--  In no event shall Enterasys Networks be liable for any incidental,
--  indirect, special, or consequential damages whatsoever (including
--  but not limited to lost profits) arising out of or related to this
--  document or the information contained in it, even if Enterasys
--  Networks has been advised of, known, or should have known, the
--  possibility of such damages.
--  Enterasys Networks grants vendors, end-users, and other interested
--  parties a non-exclusive license to use this Specification in 
--  connection with the management of Enterasys Networks products.

--  Copyright March, 2002 Enterasys Networks, Inc.

        FROM SNMPv2-SMI
--  TruthValue
--      FROM SNMPv2-TC
        FROM SNMPv2-CONF
        FROM IEEE8021-PAE-MIB

etsysEncr8021xRekeyingMIB MODULE-IDENTITY
    LAST-UPDATED "200203142049Z"  -- Thu Mar 14 20:49 GMT 2002
    ORGANIZATION "Enterasys Networks, Inc"
        "Postal: Enterasys Networks
                 35 Industrial Way, P.O. Box 5005
                 Rochester, NH 03867-0505

         Phone:  +1 603 332 9400

    -- This is the overall description of this MIB module
        "The Enterasys Networks MIB module for configuring rapid
         rekeying on SNMPv1-only platforms.

         This MIB includes encrypted variants of selected objects
         from the Enterasys 802.1x Rapid Rekeying MIB.


                                   N O T I C E

              Use of this MIB in any product requires the approval
              of the Office of the CTO, Enterasys Networks, Inc.  
              Permission to use this MIB will not be granted for 
              products in which SNMPv3 is now, or will soon be,
              implemented.  Permission to use this MIB in products
              that are never scheduled to implement SNMPv3 will be 
              granted on a case-by-case basis, depending on what 
              other suitable, secure means of configuration are
              available in the product.


         The following is a discussion of the encoding/decoding and
         encryption/decryption methods that must be used to extract
         data from an encrypted OCTET STRING.  (These methods are the
         same as for the Enterasys Networks encrypted RADIUS Client
         The encryption/decryption methods make use of an agreed-upon
         Secret and an Authenticator shared between the SNMP network
         management system and the entity that implements the MIB.

         The encryption/decryption algorithm, as presented herein, is
         taken from the RADIUS protocol, and is the method specified
         for encryption of Tunnel-Password Attributes in RFC 2868.

         To permit plug-and-play remote installation, configuration,
         and management of the device, the device will algorithmically
         derive the initial shared secret and the initial authenticator.

         For security reasons, the network manager should change the
         authenticator portion of the management encryption key after
         initial configuration.  The methods available for doing this
         are implementation-specific and subject to change.  (On the
         RoamAbout AccessPoint 2000, the encrypted RADIUS client MIB
         contains an authenticator object used for both that MIB and
         this one.)

         All read-write and write-only access objects except the table
         index are encoded into fields in an OCTET STRING.

         Octet String

         Before encryption, the 'native' objects must be encoded into
         a formatted Octet String.  After decryption, the Octet String
         must be decoded to obtain the 'native' objects.

      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     |   Salt                        |
      |   String ...
                The data type of the non-encrypted 'native' data:

                1 = Integer32
                2 = OCTET STRING

                The length in octets of the native object sub-field of
                the Octet String, exclusive of any optional padding.
                Note that the Integrity Check sub-fields (CRC, OID-tail,
                Time Stamp, Source IP Address) are not included in this
                length value, but since the IC sub-fields are always
                present and are of fixed length, there is no impediment
                to proper packet parsing.


                The Salt field is two octets in length and is used to
                ensure the uniqueness of the encryption key used to
                encrypt each object.

                The most significant bit (leftmost) of the Salt field
                MUST be set (1).  The contents of each Salt field in a
                given SNMP packet must be unique.

       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
      |  CRC (4 bytes)                                                |
      |  OID-tail (4 bytes)                                           |
      |  Time Stamp (4 bytes)                                         |
      |  Source IP Address (4 bytes)                                  |
      |  Object/Padding ...
                The plain-text String field consists of six logical
                sub-fields: the CRC, OID-tail, Time Stamp, Source IP
                address and native Object sub-fields (all of which are
                required), and the optional Padding sub-field.  The
                String field MUST be treated as a counted-string of
                undistinguished octets, and not as a standard
                C/UNIX-style null-terminated, printable ASCII string.
                CRC Sub-field

                  The CRC sub-field contains a 32-bit CRC (CRC-32)
                  calculated over the following concatentated sub-fields
                  of the String: the OID-tail, Time Stamp, Source IP
                  Address and unpadded native Object fields.  The CRC
                  sub-field acts as an integrity check on the decrypted
                OID-tail Sub-field
                  The OID-tail sub-field contains the least significant
                  four octets of the Object ID of the varbind.  This
                  field is included as an integrity check on the OID of
                  the varbind.
                Time Stamp Sub-field
                  The Time Stamp sub-field contains a 32-bit unsigned
                  integer value representing the time the encrypted
                  message was assembled.  This field acts as an
                  integrity check by facilitating the disposal of stale
                  or replayed messages. The time window of acceptance is
                  implementation dependant, and may be the subject of
                  local (i.e. managed entity) policy configuration.  The
                  Time Stamp is relative time, in units of seconds,
                  referenced to the sysUpTime object of the managed
                Source IP Address Sub-field
                  The Source IP Address sub-field contains an unsigned
                  32-bit representation of the IPv4 address of the
                  source of the encrypted message.  This is an added
                  check to allow verification of the source of the

                The CRC, OID-tail, Time Stamp, and Source IP Address
                sub-fields are collectively hereinafter refered to as
                the Integrity Check (IC) sub-fields.
                Object/Padding Sub-field

                    The Object sub-field contains the actual or native
                    object data followed by padding, if necessary.
                    If the combined length (in octets) of the
                    non-encrypted CRC, OID-tail, Time Stamp, Source IP
                    Address, and native Object sub-fields is not an even
                    multiple of 16, then the Padding sub-field MUST be
                    present.  If it is present, the length of the
                    Padding sub-field is variable, between 1 and 15
                    octets.  The value of the pad octets SHOULD be zero.
             Encrypting/Decrypting the String Field

                The entire String field MUST be encrypted as follows,
                prior to transmission:
                Construct a plain-text version of the String field by
                concatenating the CRC, OID-tail, Time Stamp, Source IP
                address, and native Object sub-fields.  If necessary,
                pad the resulting string until its length (in octets)
                is an even multiple of 16.  It is recommended that zero
                octets (0x00) be used for padding.  Call this plain-text

                   Shared Secret

                      The shared secret is formed from the MAC
                      (hardware) address of the primary management
                      interface of the managed device (containing the
                      RADIUS Client).  The MAC address is represented
                      as up-cased, dashed-ASCII, e.g. 08-00-2B-11-22-33.
                      The 128-bit authenticator is a pre-defined
                      constant.  The default value of the authenticator
                      is an Enterasys Networks trade secret.  This value
                      is settable and the user is advised to change it
                      from the default value after initial configuration
                      of the system.  Contact the MIB author for
                      additional information on the default value.
                Call the shared secret S, the [pseudo-random] 128-bit 
                Authenticator R, and the contents of the Salt field A.  
                Break P into 16 octet chunks p(1), p(2)...p(i), 
                where i = len(P)/16.  Call the cipher-text blocks 
                c(1), c(2)...c(i) and the final cipher-text C.
                Intermediate values b(1), b(2)...c(i) are required.
                Encryption is performed in the following manner ('+'
                indicates concatenation):
            b(1) = MD5(S + R + A)   c(1) = p(1) xor b(1)   C = c(1)
            b(2) = MD5(S + c(1))    c(2) = p(2) xor b(2)   C = C + c(2)
                         .                       .
                         .                       .
                         .                       .
            b(i) = MD5(S + c(i-1))  c(i) = p(i) xor b(i)   C = C + c(i)
                The resulting encrypted String field will contain

                On receipt, the process is reversed to yield the
                plain-text String."

    REVISION "200203142049Z"  -- Thu Mar 14 20:49 GMT 2002
        "The initial version of this MIB module."

    ::= { etsysModules 20 }

        OBJECT IDENTIFIER ::= { etsysEncr8021xRekeyingMIB 1 }

-- ---------------------------------------------------------- --
-- Textual Conventions
-- ---------------------------------------------------------- --

-- ---------------------------------------------------------- --
-- Branches of the Enterasys IEEE 802.1x Rapid Rekeying MIB
-- ---------------------------------------------------------- --

        OBJECT IDENTIFIER ::= { etsysEncrDot1xRekeyingObjects 1 }

-- ---------------------------------------------------------- --
-- The Rapid Rekeying Configuration Table
-- ---------------------------------------------------------- --

etsysEncrDot1xRekeyConfigTable OBJECT-TYPE
    SYNTAX        SEQUENCE OF EtsysEncrDot1xRekeyConfigEntry
    MAX-ACCESS    not-accessible
    STATUS        current
        "A table that contains encryption-key-related configuration
         objects for ports on which Authenticator PAEs can run."
    ::= { etsysEncrDot1xRekeyBaseBranch 1 }

etsysEncrDot1xRekeyConfigEntry OBJECT-TYPE
    SYNTAX        EtsysEncrDot1xRekeyConfigEntry
    MAX-ACCESS    not-accessible
    STATUS        current
        "Each conceptual row holds encryption key configuration
         information for the Authenticator PAEs associated with one
    INDEX { dot1xPaePortNumber }
    ::= { etsysEncrDot1xRekeyConfigTable 1 }

EtsysEncrDot1xRekeyConfigEntry ::=
               etsysEncrDot1xRekeyEnabled           OCTET STRING,
               etsysEncrDot1xRekeyPeriod            OCTET STRING,
               etsysEncrDot1xRekeyLength            OCTET STRING,
               etsysEncrDot1xRekeyAsymmetric        OCTET STRING

etsysEncrDot1xRekeyEnabled OBJECT-TYPE
    SYNTAX        OCTET STRING (SIZE(0..255)) -- encrypted TruthValue
    MAX-ACCESS    read-write
    STATUS        current
            "An encrypted version of etsysDot1xRekeyEnabled.

                 Determines how an access point selects radio encryption

                 If the selected port does not support the EAPOL-Key
                 feature (e.g., because radio keys are not applicable
                 to Ethernet ports), this object will have a value of
                 FALSE and attempts to write TRUE will fail.

                 Normally, if radio keys are present, the manager enters
                 them into the access point through some manual process.
                 The manager or the users may also need to configure the
                 keys into each laptop (access points can distribute the
                 keys automatically to 802.1x EAP-TLS clients).  However
                 laptops get keys, the keys remain static until somebody
                 goes to the trouble of changing them.  If the keys stay
                 unchanged for long periods, this can make it easier for
                 a determined attacker to launch a cryptographic attack.

                 When rapid rekeying is enabled, an access point ignores
                 its manually-set keys.  It generates pseudo-random keys
                 on a periodic basis, using IEEE 802.1x key distribution
                 to deliver the keys to new and current clients.

                 Do not enable rapid rekeying unless ALL of your clients
                 support IEEE 802.1x and an authentication method (e.g.,
                 EAP-TLS) that supports key distribution.

                 Before enabling rapid rekeying, make sure that you have
                 set 'dot1xAuthKeyTxEnabled' to TRUE.  Changing the keys
                 without telling any of the clients about the changes is
                 not a very useful mode of operation.

             The data type is 1, Integer32."
--  DEFVAL { encrypt(false) }
    ::= { etsysEncrDot1xRekeyConfigEntry 1 }

etsysEncrDot1xRekeyPeriod OBJECT-TYPE
    SYNTAX        OCTET STRING (SIZE(0..255)) -- encrypted Unsigned32
    MAX-ACCESS    read-write
    STATUS        current
            "An encrypted version of etsysDot1xRekeyPeriod.

                    When rapid rekeying (periodic changing of radio
                    keys) is enabled, the value of this object
                    determines the period, in seconds, between key

             The data type is 1, Integer32."
--  DEFVAL { encrypt(1800) }
    ::= { etsysEncrDot1xRekeyConfigEntry 2 }

etsysEncrDot1xRekeyLength OBJECT-TYPE
    SYNTAX        OCTET STRING (SIZE(0..255)) -- encrypted enumeration
    MAX-ACCESS    read-write
    STATUS        current
            "An encrypted version of etsysDot1xRekeyLength.

                SYNTAX INTEGER {  keylen40 (1),   keylen128 (2) }

                Determines the number of bits/bytes used in the
                encryption keys.  Currently supports either 128-bit
                (16-octet) encryption keys or 40-bit (5-octet)
                encryption keys.

             The data type is 1, Integer32."
--  DEFVAL { encrypt(keylen128) }
    ::= { etsysEncrDot1xRekeyConfigEntry 3 }

etsysEncrDot1xRekeyAsymmetric OBJECT-TYPE
    SYNTAX        OCTET STRING (SIZE(0..255)) -- encrypted TruthValue
    MAX-ACCESS    read-write
    STATUS        current
            "An encrypted version of etsysDot1xRekeyAsymmetric.

                Determines the association between the supplicant and
                authenticator transmit keys.

                If true(1), the authenticator and supplicant will use
                different encryption keys in order to transmit data.

                If false(2), the authenticator and supplicant will use
                a single key pattern to encrypt the transmitted data.

             The data type is 1, Integer32."
--  DEFVAL { encrypt(true) }
    ::= { etsysEncrDot1xRekeyConfigEntry 4 }

-- ---------------------------------------------------------- --
-- Enterasys 802.1X Rekeying MIB - Conformance Information
-- ---------------------------------------------------------- --

    OBJECT IDENTIFIER ::= { etsysEncr8021xRekeyingMIB 2 }

    OBJECT IDENTIFIER ::= { etsysEncrDot1xRekeyingConformance 1 }

    OBJECT IDENTIFIER ::= { etsysEncrDot1xRekeyingConformance 2 }

-- ---------------------------------------------------------- --
-- Units of conformance
-- ---------------------------------------------------------- --

etsysEncrDot1xRekeyingBaseGroup OBJECT-GROUP
    STATUS current
            "A collection of objects providing rekeying configuration
             information about a port on which Authenticator PAEs can
    ::= { etsysEncrDot1xRekeyingGroups 1 }

-- ---------------------------------------------------------- --
-- Compliance statements
-- ---------------------------------------------------------- --

etsysEncrDot1xRekeyingCompliance MODULE-COMPLIANCE
    STATUS current
            "The compliance statement for devices that support the
             Enterasys IEEE 802.1x extensions MIB."


    MANDATORY-GROUPS { etsysEncrDot1xRekeyingBaseGroup }

    OBJECT         etsysEncrDot1xRekeyEnabled
    MIN-ACCESS     read-only
    DESCRIPTION    "Write access is not required."

    OBJECT         etsysEncrDot1xRekeyPeriod
    MIN-ACCESS     read-only
    DESCRIPTION    "Write access is not required."

    OBJECT         etsysEncrDot1xRekeyLength
    MIN-ACCESS     read-only
    DESCRIPTION    "Write access is not required.  Depending upon
                   product capabilities (and export restrictions,
                   if applicable), some systems may not implement
                   all key lengths."

    OBJECT         etsysEncrDot1xRekeyAsymmetric
    MIN-ACCESS     read-only
    DESCRIPTION    "Write access is not required."

::= { etsysEncrDot1xRekeyingCompliances 1 }