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RFC 5676

Definitions of Managed Objects for Mapping SYSLOG Messages to Simple Network Management Protocol (SNMP) Notifications

Pages: 22
Proposed Standard
Errata

Top   ToC   RFC5676 - Page 1
Network Working Group                                   J. Schoenwaelder
Request for Comments: 5676                      Jacobs University Bremen
Category: Standards Track                                       A. Clemm
                                                           Cisco Systems
                                                             A. Karmakar
                                             Cisco Systems India Pvt Ltd
                                                            October 2009


     Definitions of Managed Objects for Mapping SYSLOG Messages to
        Simple Network Management Protocol (SNMP) Notifications

Abstract

This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it defines a mapping of SYSLOG messages to Simple Network Management Protocol (SNMP) notifications. Status of This Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the BSD License.
Top   ToC   RFC5676 - Page 2

Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. The Internet-Standard Management Framework . . . . . . . . . . 2 3. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5. Relationship to Other MIB Modules . . . . . . . . . . . . . . 4 6. Relationship to the SNMP Notification to SYSLOG Mapping . . . 6 7. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 5 8. Usage Example . . . . . . . . . . . . . . . . . . . . . . . . 18 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 10. Security Considerations . . . . . . . . . . . . . . . . . . . 19 11. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 20 12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 20 12.1. Normative References . . . . . . . . . . . . . . . . . . 20 12.2. Informative References . . . . . . . . . . . . . . . . . 21

1. Introduction

SNMP ([RFC3410], [RFC3411]) and SYSLOG [RFC5424] are two widely used protocols to communicate event notifications. Although co-existence of several management protocols in one operational environment is possible, certain environments require that all event notifications be collected by a single system daemon, such as a SYSLOG collector or an SNMP notification receiver, via a single management protocol. In such environments, it is necessary to translate event notifications between management protocols. This document defines an SNMP MIB module to represent SYSLOG messages and to send SYSLOG messages as SNMP notifications to SNMP notification receivers.

2. The Internet-Standard Management Framework

For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of RFC 3410 [RFC3410]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP). Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580].
Top   ToC   RFC5676 - Page 3

3. Conventions

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].

4. Overview

SYSLOG messages are translated to SNMP by a SYSLOG-to-SNMP translator. Such a translator acts as a SYSLOG collector [RFC5424] and implements a MIB module according to the SNMP architecture [RFC3411]. The translator might be tightly coupled to an SNMP agent or it might interface with an SNMP agent via a subagent protocol. After initialization, the SYSLOG-to-SNMP translator will listen for SYSLOG messages. On receiving a message, the message will be parsed to extract information as described in the MIB module. A conceptual table is populated with information extracted from the SYSLOG message, and finally a notification may be generated. The MIB module is organized into a group of scalars and two tables. The syslogMsgControl group contains two scalars controlling the maximum size of SYSLOG messages recorded in the tables and also controlling whether SNMP notifications are generated for SYSLOG messages. --syslogMsgObjects(1) | +--syslogMsgControl(1) | +-- Unsigned32 syslogMsgTableMaxSize(1) +-- TruthValue syslogMsgEnableNotifications(2) The syslogMsgTable contains one entry for each recorded SYSLOG message. The basic fields of SYSLOG messages as well as message properties are represented in different columns of the conceptual table. --syslogMsgObjects(1) | +--syslogMsgTable(2) | +--syslogMsgEntry(1) [syslogMsgIndex] | +-- Unsigned32 syslogMsgIndex(1) +-- SyslogFacility syslogMsgFacility(2) +-- SyslogSeverity syslogMsgSeverity(3) +-- Unsigned32 syslogMsgVersion(4)
Top   ToC   RFC5676 - Page 4
           +-- SyslogTimeStamp syslogMsgTimeStamp(5)
           +-- DisplayString   syslogMsgHostName(6)
           +-- DisplayString   syslogMsgAppName(7)
           +-- DisplayString   syslogMsgProcID(8)
           +-- DisplayString   syslogMsgMsgID(9)
           +-- Unsigned32      syslogMsgSDParams(10)
           +-- OctetString     syslogMsgMsg(11)

   The syslogMsgSDTable contains one entry for each structured data
   element parameter contained in a SYSLOG message.  Since structured
   data elements are optional, the relationship between the
   syslogMsgTable and the syslogMsgSDTable ranges from one-to-zero to
   one-to-many.

   --syslogMsgObjects(1)
     |
     +--syslogMsgSDTable(3)
        |
        +--syslogMsgSDEntry(1)       [syslogMsgIndex,
           |                          syslogMsgSDParamIndex,
           |                          syslogMsgSDID,
           |                          syslogMsgSDParamName]
           |
           +-- Unsigned32             syslogMsgSDParamIndex(1)
           +-- DisplayString          syslogMsgSDID(2)
           +-- DisplayString          syslogMsgSDParamName(3)
           +-- SyslogParamValueString syslogMsgSDParamValue(4)

5. Relationship to Other MIB Modules

The NOTIFICATION-LOG-MIB [RFC3014] provides a generic mechanism for logging SNMP notifications in order to deal with lost SNMP notifications, e.g., due to transient communication problems. Applications can poll the notification log to verify that they have not missed important SNMP notifications. The MIB module defined in this memo provides a mechanism for logging SYSLOG notifications. This additional SYSLOG notification log is provided because (a) SYSLOG messages might not lead to SNMP notification (this is configurable) and (b) SNMP notifications might not carry all information associated with a SYSLOG notification. The MIB module IMPORTS objects from SNMPv2-SMI [RFC2578], SNMPv2-TC [RFC2579], SNMPv2-CONF [RFC2580], SNMP-FRAMEWORK-MIB [RFC3411], and SYSLOG-TC-MIB [RFC5427].
Top   ToC   RFC5676 - Page 5
   The textual convention SyslogParamValueString uses the UTF-8
   transformation format of the ISO/IEC IS 10646-1 character set defined
   in [RFC3629].

6. Relationship to the SNMP Notification to SYSLOG Mapping

A companion document [RFC5675] defines a mapping of SNMP notifications to SYSLOG messages. This section discusses the possibilities of using both specifications in combination. A SYSLOG collector implementing the SYSLOG-MSG-MIB module and the mapping of SNMP notifications to SYSLOG messages may be configured to translate received SYSLOG messages containing SNMP notifications back into the original SNMP notification. In this case, the relevant tables of the SYSLOG-MSG-MIB will not be populated for SYSLOG messages carrying SNMP notifications. This configuration allows operators to build a forwarding chain where SNMP notifications are "tunneled" through SYSLOG messages. Due to size restrictions of the SYSLOG transports and the more verbose textual encoding used by SYSLOG, there is a possibility that SNMP notification content will get truncated when tunneled through SYSLOG, and thus the resulting SNMP notification may be incomplete. An SNMP management application supporting the SYSLOG-MSG-MIB and the mapping of SNMP notifications to SYSLOG messages may process information from the SYSLOG-MSG-MIB in order to emit a SYSLOG message representing the SYSLOG message recorded in the SYSLOG-MSG-MIB module. This configuration allows operators to build a forwarding chain where SYSLOG messages are "tunneled" through SNMP messages. A notification receiver can determine whether a syslogMsgNotification contained all structured data element parameters of a SYSLOG message. In case parameters are missing, a forwarding application MUST retrieve the missing parameters from the SYSLOG-MSG-MIB. Regular polling of the SYSLOG-MSG-MIB can be used to take care of any lost SNMP notifications.

7. Definitions

SYSLOG-MSG-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, Unsigned32, mib-2 FROM SNMPv2-SMI TEXTUAL-CONVENTION, DisplayString, TruthValue FROM SNMPv2-TC OBJECT-GROUP, NOTIFICATION-GROUP, MODULE-COMPLIANCE FROM SNMPv2-CONF SyslogFacility, SyslogSeverity
Top   ToC   RFC5676 - Page 6
         FROM SYSLOG-TC-MIB;

 syslogMsgMib MODULE-IDENTITY
     LAST-UPDATED "200908130800Z"
     ORGANIZATION "IETF OPSAWG Working Group"
     CONTACT-INFO
         "Juergen Schoenwaelder
          <j.schoenwaelder@jacobs-university.de>
          Jacobs University Bremen
          Campus Ring 1
          28757 Bremen
          Germany

          Alexander Clemm
          <alex@cisco.com>
          Cisco Systems
          170 West Tasman Drive
          San Jose, CA 95134-1706
          USA

          Anirban Karmakar
          <akarmaka@cisco.com>
          Cisco Systems India Pvt Ltd
          SEZ Unit, Cessna Business Park,
          Sarjapur Marathahalli ORR,
          Bangalore, Karnataka 560103
          India"

     DESCRIPTION
         "This MIB module represents SYSLOG messages as SNMP objects.

          Copyright (c) 2009 IETF Trust and the persons identified as
          authors of the code.  All rights reserved.

          Redistribution and use in source and binary forms, with or
          without modification, is permitted pursuant to, and subject
          to the license terms contained in, the Simplified BSD License
          set forth in Section 4.c of the IETF Trust's Legal Provisions
          Relating to IETF Documents
          (http://trustee.ietf.org/license-info).

          This version of this MIB module is part of RFC 5676; see
          the RFC itself for full legal notices."

     REVISION "200908130800Z"
     DESCRIPTION
         "Initial version issued as part of RFC 5676."
     ::= { mib-2 192 }
Top   ToC   RFC5676 - Page 7
 -- textual convention definitions

 SyslogTimeStamp ::= TEXTUAL-CONVENTION
     DISPLAY-HINT "2d-1d-1d,1d:1d:1d.3d,1a1d:1d"
     STATUS       current
     DESCRIPTION
        "A date-time specification.  This type is similar to the
         DateAndTime type defined in the SNMPv2-TC, except the
         subsecond granulation is microseconds instead of
         deciseconds and a zero-length string can be used
         to indicate a missing value.

         field  octets  contents                  range
         -----  ------  --------                  -----
           1      1-2   year*                     0..65536
           2       3    month                     1..12
           3       4    day                       1..31
           4       5    hour                      0..23
           5       6    minutes                   0..59
           6       7    seconds                   0..60
                        (use 60 for leap-second)
           7     8-10   microseconds*             0..999999
           8      11    direction from UTC        '+' / '-'
           9      12    hours from UTC*           0..13
          10      13    minutes from UTC          0..59

         * Notes:
         - the value of year is in network-byte order
         - the value of microseconds is in network-byte order
         - daylight saving time in New Zealand is +13

         For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be
         displayed as:

                         1992-5-26,13:30:15.0,-4:0

         Note that if only local time is known, then timezone
         information (fields 11-13) is not present."
     SYNTAX      OCTET STRING (SIZE (0 | 10 | 13))

 SyslogParamValueString ::= TEXTUAL-CONVENTION
     DISPLAY-HINT "65535t"
     STATUS       current
     DESCRIPTION
        "The value of a SYSLOG SD-PARAM is represented using the
         ISO/IEC IS 10646-1 character set, encoded as an octet string
         using the UTF-8 transformation format described in RFC 3629.
Top   ToC   RFC5676 - Page 8
         Since additional code points are added by amendments to the
         10646 standard from time to time, implementations must be
         prepared to encounter any code point from 0x00000000 to
         0x7fffffff.  Byte sequences that do not correspond to the
         valid UTF-8 encoding of a code point or that are outside this
         range are prohibited.  Similarly, overlong UTF-8 sequences
         are prohibited.

         UTF-8 may require multiple bytes to represent a single
         character / code point; thus, the length of this object in
         octets may be different from the number of characters
         encoded.  Similarly, size constraints refer to the number of
         encoded octets, not the number of characters represented by
         an encoding."
     REFERENCE
        "RFC 3629: UTF-8, a transformation format of ISO 10646"
     SYNTAX     OCTET STRING

 -- object definitions

 syslogMsgNotifications OBJECT IDENTIFIER ::= { syslogMsgMib 0 }
 syslogMsgObjects       OBJECT IDENTIFIER ::= { syslogMsgMib 1 }
 syslogMsgConformance   OBJECT IDENTIFIER ::= { syslogMsgMib 2 }

 syslogMsgControl       OBJECT IDENTIFIER ::= { syslogMsgObjects 1 }

 syslogMsgTableMaxSize OBJECT-TYPE
     SYNTAX      Unsigned32
     MAX-ACCESS  read-write
     STATUS      current
     DESCRIPTION
        "The maximum number of SYSLOG messages that may be held in
         syslogMsgTable.  A particular setting does not guarantee that
         there is sufficient memory available for the maximum number
         of table entries indicated by this object.  A value of 0 means
         no fixed limit.

         If an application reduces the limit while there are SYSLOG
         messages in the syslogMsgTable, the SYSLOG messages that are
         in the syslogMsgTable for the longest time MUST be discarded
         to bring the table down to the new limit.

         The value of this object should be kept in nonvolatile
         memory."
     DEFVAL      { 0 }
     ::= { syslogMsgControl 1 }

 syslogMsgEnableNotifications OBJECT-TYPE
Top   ToC   RFC5676 - Page 9
     SYNTAX      TruthValue
     MAX-ACCESS  read-write
     STATUS      current
     DESCRIPTION
        "Indicates whether syslogMsgNotification notifications are
         generated.

         The value of this object should be kept in nonvolatile
         memory."
     DEFVAL      { false }
     ::= { syslogMsgControl 2 }

 syslogMsgTable OBJECT-TYPE
     SYNTAX      SEQUENCE OF SyslogMsgEntry
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
        "A table containing recent SYSLOG messages.  The size of the
         table is controlled by the syslogMsgTableMaxSize object."
     ::= { syslogMsgObjects 2 }

 syslogMsgEntry OBJECT-TYPE
     SYNTAX      SyslogMsgEntry
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
        "An entry of the syslogMsgTable."
     INDEX { syslogMsgIndex }
     ::= { syslogMsgTable 1 }

 SyslogMsgEntry ::= SEQUENCE {
     syslogMsgIndex      Unsigned32,
     syslogMsgFacility   SyslogFacility,
     syslogMsgSeverity   SyslogSeverity,
     syslogMsgVersion    Unsigned32,
     syslogMsgTimeStamp  SyslogTimeStamp,
     syslogMsgHostName   DisplayString,
     syslogMsgAppName    DisplayString,
     syslogMsgProcID     DisplayString,
     syslogMsgMsgID      DisplayString,
     syslogMsgSDParams   Unsigned32,
     syslogMsgMsg        OCTET STRING
 }

 syslogMsgIndex OBJECT-TYPE
     SYNTAX      Unsigned32 (1..4294967295)
     MAX-ACCESS  not-accessible
     STATUS      current
Top   ToC   RFC5676 - Page 10
     DESCRIPTION
        "A monotonically increasing number used to identify entries in
         the syslogMsgTable.  When syslogMsgIndex reaches the maximum
         value (4294967295), the value wraps back to 1.

         Applications periodically polling the syslogMsgTable for new
         entries should take into account that a complete rollover of
         syslogMsgIndex will happen if more than 4294967294 messages
         are received during a poll interval."
     ::= { syslogMsgEntry 1 }

 syslogMsgFacility OBJECT-TYPE
     SYNTAX      SyslogFacility
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The facility of the SYSLOG message."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.1)
         RFC 5427: Textual Conventions for Syslog Management"
     ::= { syslogMsgEntry 2 }

 syslogMsgSeverity OBJECT-TYPE
     SYNTAX      SyslogSeverity
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The severity of the SYSLOG message"
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.1)
         RFC 5427: Textual Conventions for Syslog Management"
     ::= { syslogMsgEntry 3 }

 syslogMsgVersion OBJECT-TYPE
     SYNTAX      Unsigned32 (0..999)
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The version of the SYSLOG message.  A value of 0 indicates
         that the version is unknown."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.2)"
     ::= { syslogMsgEntry 4 }

 syslogMsgTimeStamp OBJECT-TYPE
     SYNTAX      SyslogTimeStamp
     MAX-ACCESS  read-only
     STATUS      current
Top   ToC   RFC5676 - Page 11
     DESCRIPTION
        "The timestamp of the SYSLOG message.  A zero-length
         string is returned if the timestamp is unknown."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.3)"
     ::= { syslogMsgEntry 5 }

 syslogMsgHostName OBJECT-TYPE
     SYNTAX      DisplayString (SIZE (0..255))
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The hostname and the (optional) domain name of the SYSLOG
         message.  A zero-length string indicates an unknown hostname.
         The SYSLOG protocol specification constrains this string to
         printable US-ASCII code points."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.4)"
     ::= { syslogMsgEntry 6 }

 syslogMsgAppName OBJECT-TYPE
     SYNTAX      DisplayString (SIZE (0..48))
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The app-name of the SYSLOG message.  A zero-length string
         indicates an unknown app-name.  The SYSLOG protocol
         specification constrains this string to printable US-ASCII
         code points."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.5)"
     ::= { syslogMsgEntry 7 }

 syslogMsgProcID OBJECT-TYPE
     SYNTAX      DisplayString (SIZE (0..128))
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The procid of the SYSLOG message.  A zero-length string
         indicates an unknown procid.  The SYSLOG protocol
         specification constrains this string to printable
         US-ASCII code points."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.6)"
     ::= { syslogMsgEntry 8 }

 syslogMsgMsgID OBJECT-TYPE
     SYNTAX      DisplayString (SIZE (0..32))
Top   ToC   RFC5676 - Page 12
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The msgid of the SYSLOG message.  A zero-length string
         indicates an unknown msgid.  The SYSLOG protocol specification
         constrains this string to printable US-ASCII code points."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.2.7)"
     ::= { syslogMsgEntry 9 }

 syslogMsgSDParams OBJECT-TYPE
     SYNTAX      Unsigned32
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The total number of structured data element parameters
         carried in the SYSLOG message.  This number effectively
         indicates the number of entries in the syslogMsgSDTable.
         It can be used, for example, by a notification receiver
         to determine whether a notification carried all
         structured data element parameters of a SYSLOG message."
     ::= { syslogMsgEntry 10 }

 syslogMsgMsg OBJECT-TYPE
     SYNTAX      OCTET STRING
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The message part of the SYSLOG message.  The syntax does not
         impose a size restriction.  Implementations of this MIB module
         may truncate the message part of the SYSLOG message such that
         it fits into the size constraints imposed by the implementation
         environment.  Such truncations can also happen elsewhere in the
         SYSLOG forwarding chain.

         If the first octets contain the value 'EFBBBF'h, then the rest
         of the message is a UTF-8 string.  Since SYSLOG messages may be
         truncated at arbitrary octet boundaries during forwarding, the
         message may contain invalid UTF-8 encodings at the end."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Sections 6.1 and 6.4)"
     ::= { syslogMsgEntry 11 }

 syslogMsgSDTable OBJECT-TYPE
     SYNTAX      SEQUENCE OF SyslogMsgSDEntry
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
Top   ToC   RFC5676 - Page 13
        "A table containing structured data elements of SYSLOG
         messages."
     ::= { syslogMsgObjects 3 }

 syslogMsgSDEntry OBJECT-TYPE
     SYNTAX      SyslogMsgSDEntry
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
        "An entry of the syslogMsgSDTable."
     INDEX { syslogMsgIndex, syslogMsgSDParamIndex,
             syslogMsgSDID, syslogMsgSDParamName }
     ::= { syslogMsgSDTable 1 }

 SyslogMsgSDEntry ::= SEQUENCE {
     syslogMsgSDParamIndex  Unsigned32,
     syslogMsgSDID          DisplayString,
     syslogMsgSDParamName   DisplayString,
     syslogMsgSDParamValue  SyslogParamValueString
 }

 syslogMsgSDParamIndex OBJECT-TYPE
     SYNTAX      Unsigned32 (1..4294967295)
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
        "This object indexes the structured data element parameters
         contained in a SYSLOG message.  The first structured data
         element parameter has the index value 1, and subsequent
         parameters are indexed by incrementing the index of the
         previous parameter.  The index increases across structured
         data element boundaries so that the value reflects the
         position of a structured data element parameter in a
         SYSLOG message."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.3.3)"
     ::= { syslogMsgSDEntry 1 }

 syslogMsgSDID OBJECT-TYPE
     SYNTAX      DisplayString (SIZE (1..32))
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
        "The name (SD-ID) of a structured data element.  The SYSLOG
         protocol specification constrains this string to printable
         US-ASCII code points."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.3.2)"
Top   ToC   RFC5676 - Page 14
     ::= { syslogMsgSDEntry 2 }

 syslogMsgSDParamName OBJECT-TYPE
     SYNTAX      DisplayString (SIZE (1..32))
     MAX-ACCESS  not-accessible
     STATUS      current
     DESCRIPTION
        "The name of a parameter of the structured data element.  The
         SYSLOG protocol specification constrains this string to
         printable US-ASCII code points."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.3.3)"
     ::= { syslogMsgSDEntry 3 }

 syslogMsgSDParamValue OBJECT-TYPE
     SYNTAX      SyslogParamValueString
     MAX-ACCESS  read-only
     STATUS      current
     DESCRIPTION
        "The value of the parameter of a SYSLOG message identified by
         the index of this table.  The value is stored in the unescaped
         format."
     REFERENCE
        "RFC 5424: The Syslog Protocol (Section 6.3.3)"
     ::= { syslogMsgSDEntry 4 }

 -- notification definitions

 syslogMsgNotification NOTIFICATION-TYPE
     OBJECTS     { syslogMsgFacility, syslogMsgSeverity,
                   syslogMsgVersion, syslogMsgTimeStamp,
                   syslogMsgHostName, syslogMsgAppName,
                   syslogMsgProcID, syslogMsgMsgID,
                   syslogMsgSDParams, syslogMsgMsg }
     STATUS      current
     DESCRIPTION
        "The syslogMsgNotification is generated when a new SYSLOG
         message is received and the value of
         syslogMsgGenerateNotifications is true.

         Implementations may add syslogMsgSDParamValue objects as long
         as the resulting notification fits into the size constraints
         imposed by the implementation environment and the notification
         message size constraints imposed by maxMessageSize [RFC3412]
         and SNMP transport mappings."
     ::= { syslogMsgNotifications 1 }

 -- conformance statements
Top   ToC   RFC5676 - Page 15
 syslogMsgGroups      OBJECT IDENTIFIER ::= { syslogMsgConformance 1 }
 syslogMsgCompliances OBJECT IDENTIFIER ::= { syslogMsgConformance 2 }

 syslogMsgFullCompliance MODULE-COMPLIANCE
     STATUS      current
     DESCRIPTION
        "The compliance statement for implementations of the
         SYSLOG-MSG-MIB."
     MODULE      -- this module
     MANDATORY-GROUPS {
         syslogMsgGroup,
         syslogMsgSDGroup,
         syslogMsgControlGroup,
         syslogMsgNotificationGroup
     }
     ::= { syslogMsgCompliances 1 }

 syslogMsgReadOnlyCompliance MODULE-COMPLIANCE
     STATUS      current
     DESCRIPTION
        "The compliance statement for implementations of the
         SYSLOG-MSG-MIB that do not support read-write access."
     MODULE      -- this module
     MANDATORY-GROUPS {
         syslogMsgGroup,
         syslogMsgSDGroup,
         syslogMsgControlGroup,
         syslogMsgNotificationGroup
     }
     OBJECT syslogMsgTableMaxSize
        MIN-ACCESS  read-only
        DESCRIPTION
           "Write access is not required."
     OBJECT syslogMsgEnableNotifications
        MIN-ACCESS  read-only
        DESCRIPTION
           "Write access is not required."
     ::= { syslogMsgCompliances 2 }

 syslogMsgNotificationCompliance MODULE-COMPLIANCE
     STATUS      current
     DESCRIPTION
        "The compliance statement for implementations of the
         SYSLOG-MSG-MIB that do only generate notifications and do not
         provide a table to allow read access to SYSLOG message
         details."
     MODULE      -- this module
     MANDATORY-GROUPS {
Top   ToC   RFC5676 - Page 16
         syslogMsgGroup,
         syslogMsgSDGroup,
         syslogMsgNotificationGroup
     }
     OBJECT      syslogMsgFacility
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
         "Read access is not required."
     OBJECT      syslogMsgSeverity
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgVersion
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgTimeStamp
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgHostName
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgAppName
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgProcID
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgMsgID
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgSDParams
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgMsg
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
     OBJECT      syslogMsgSDParamValue
     MIN-ACCESS  accessible-for-notify
     DESCRIPTION
        "Read access is not required."
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     ::= { syslogMsgCompliances 3 }

 syslogMsgNotificationGroup NOTIFICATION-GROUP
     NOTIFICATIONS {
         syslogMsgNotification
     }
     STATUS      current
     DESCRIPTION
        "The notifications emitted by this MIB module."
     ::= { syslogMsgGroups 1 }

 syslogMsgGroup OBJECT-GROUP
     OBJECTS {
         -- syslogMsgIndex,
         syslogMsgFacility,
         syslogMsgSeverity,
         syslogMsgVersion,
         syslogMsgTimeStamp,
         syslogMsgHostName,
         syslogMsgAppName,
         syslogMsgProcID,
         syslogMsgMsgID,
         syslogMsgSDParams,
         syslogMsgMsg
     }
     STATUS      current
     DESCRIPTION
        "A collection of objects representing a SYSLOG message,
         excluding structured data elements."
     ::= { syslogMsgGroups 2 }

 syslogMsgSDGroup OBJECT-GROUP
     OBJECTS {
         -- syslogMsgSDParamIndex,
         -- syslogMsgSDID,
         -- syslogMsgSDParamName,
         syslogMsgSDParamValue
     }
     STATUS      current
     DESCRIPTION
        "A collection of objects representing the structured data
         elements of a SYSLOG message."
     ::= { syslogMsgGroups 3 }

 syslogMsgControlGroup OBJECT-GROUP
     OBJECTS {
         syslogMsgTableMaxSize,
         syslogMsgEnableNotifications
Top   ToC   RFC5676 - Page 18
     }
     STATUS      current
     DESCRIPTION
        "A collection of control objects to control the size of the
         syslogMsgTable and to enable/disable notifications."
     ::= { syslogMsgGroups 4 }

 END

8. Usage Example

The following example shows a valid SYSLOG message including structured data. The otherwise-unprintable Unicode byte order mark (BOM) is represented as "BOM" in the example. <165>1 2003-10-11T22:14:15.003Z mymachine.example.com evntslog - ID47 [exampleSDID@32473 iut="3" eventSource="Application" eventID="1011"] BOMAn application event log entry... This SYSLOG message leads to the following entries in the syslogMsgTable and the syslogMsgSDTable (note that string indexes are written as strings for readability reasons): syslogMsgIndex.1 = 1 syslogMsgFacility.1 = 20 syslogMsgSeverity.1 = 5 syslogMsgVersion.1 = 1 syslogMsgTimeStamp.1 = 2003-10-11,22:14:15.003,+0:0 syslogMsgHostName.1 = "mymachine.example.com" syslogMsgAppName.1 = "evntslog" syslogMsgProcID.1 = "-" syslogMsgMsgID.1 = "ID47" syslogMsgMsg.1 = "BOMAn application event log entry..." syslogMsgSDParamValue.1.1."exampleSDID@32473"."iut" = "3" syslogMsgSDParamValue.1.2."exampleSDID@32473"."eventSource" = "Application" syslogMsgSDParamValue.1.3."exampleSDID@32473"."eventID" = "1011"

9. IANA Considerations

The IANA has assigned value "192" under the 'mib-2' subtree and recorded the assignment in the SMI Numbers registry.
Top   ToC   RFC5676 - Page 19

10. Security Considerations

There are a number of management objects defined in this MIB module with a MAX-ACCESS clause of read-write and/or read-create. Such objects may be considered sensitive or vulnerable in some network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. These are the tables and objects and their sensitivity/vulnerability: o syslogMsgTableMaxSize: This object controls how many entries are kept in the syslogMsgTable. Unauthorized modifications may either cause increased memory consumption (by setting this object to a large value) or turn off the capability to retrieve notifications using GET class operations (by setting this object to zero). This might be used to hide traces of an attack. o syslogMsgEnableNotifications: This object enables notifications. Unauthorized modifications to disable notification generation can be used to hide an attack by preventing management applications that use SNMP from receiving real-time notifications about events carried in SYSLOG messages. Unauthorized modifications to enable notification generation may be used as part of a denial-of-service attack against a network management system if, for example, the SYSLOG-to-SNMP translator accepts unauthorized SYSLOG messages. Some of the readable objects in this MIB module (i.e., objects with a MAX-ACCESS other than not-accessible) may be considered sensitive or vulnerable in some network environments. It is thus important to control even GET and/or NOTIFY access to these objects and possibly to even encrypt the values of these objects when sending them over the network via SNMP. These are the tables and objects and their sensitivity/vulnerability: o syslogMsgTableMaxSize, syslogMsgEnableNotifications: These objects provide information regarding whether SYSLOG messages are forwarded as SNMP notifications and how many messages will be maintained in the syslogMsgTable. This information might be exploited by an attacker in order to plan actions with the goal of hiding attack activities. o syslogMsgFacility, syslogMsgSeverity, syslogMsgVersion, syslogMsgTimeStamp, syslogMsgHostName, syslogMsgAppName, syslogMsgProcID, syslogMsgMsgID, syslogMsgSDParams, syslogMsgMsg, syslogMsgSDParamValue: These objects carry the content of SYSLOG messages and the SYSLOG-message-oriented security considerations of [RFC5424] apply. In particular, an attacker who gains access to SYSLOG messages via SNMP may use the knowledge gained from
Top   ToC   RFC5676 - Page 20
      SYSLOG messages to compromise a machine or do other damage.  It is
      therefore desirable to configure SNMP access control rules,
      enforcing a consistent security policy for SYSLOG messages.

   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example by using IPsec),
   even then, 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 module.

   It is RECOMMENDED that implementers consider the security features as
   provided by the SNMPv3 framework (see [RFC3410], section 8),
   including full support for the SNMPv3 cryptographic mechanisms (for
   authentication and privacy).

   Further, deployment of SNMP versions prior to SNMPv3 is NOT
   RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
   enable cryptographic security.  It is then a customer/operator
   responsibility to ensure that the SNMP entity giving access to an
   instance of this MIB module is properly configured to give access to
   the objects only to those principals (users) that have legitimate
   rights to indeed GET or SET (change/create/delete) them.

   Using the security features of the SNMPv3 framework secures the
   transport of SYSLOG data via SNMP only.  It is therefore RECOMMENDED
   that deployments use SYSLOG security mechanisms in order to prevent
   attackers from adding malicious SYSLOG data to the MIB tables.

11. Acknowledgments

The editors wish to thank the following individuals for providing helpful comments on various versions of this document: Martin Bjorklund, Washam Fan, Rainer Gerhards, Wes Hardacker, David Harrington, Tom Petch, Juergen Quittek, Dan Romascanu, and Bert Wijnen.

12. References

12.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2578] McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Structure of Management Information Version 2 (SMIv2)", RFC 2578, STD 58, April 1999.
Top   ToC   RFC5676 - Page 21
   [RFC2579]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,
              "Textual Conventions for SMIv2", RFC 2579, STD 58,
              April 1999.

   [RFC2580]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,
              "Conformance Statements for SMIv2", RFC 2580, STD 58,
              April 1999.

   [RFC3411]  Harrington, D., Presuhn, R., and B. Wijnen, "An
              Architecture for Describing Simple Network Management
              Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
              December 2002.

   [RFC3412]  Case, J., Harrington, D., Presuhn, R., and B. Wijnen,
              "Message Processing and Dispatching for the Simple Network
              Management Protocol (SNMP)", STD 62, RFC 3412,
              December 2002.

   [RFC3629]  Yergeau, F., "UTF-8, a transformation format of ISO
              10646", STD 63, RFC 3629, November 2003.

   [RFC5424]  Gerhards, R., "The Syslog Protocol", RFC 5424, March 2009.

   [RFC5427]  Keeni, G., "Textual Conventions for Syslog Management",
              RFC 5427, March 2009.

   [RFC5675]  Marinov, V. and J. Schoenwaelder, "Mapping Simple Network
              Management Protocol (SNMP) Notifications to SYSLOG
              Messages", RFC 5675, October 2009.

12.2. Informative References

[RFC3014] Kavasseri, R., Ed., "Notification Log MIB", RFC 3014, November 2002. [RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction and Applicability Statements for Internet- Standard Management Framework", RFC 3410, December 2002.
Top   ToC   RFC5676 - Page 22

Authors' Addresses

Juergen Schoenwaelder Jacobs University Bremen Campus Ring 1 28725 Bremen Germany EMail: j.schoenwaelder@jacobs-university.de Alexander Clemm Cisco Systems 170 West Tasman Drive San Jose, CA 95134-1706 USA EMail: alex@cisco.com Anirban Karmakar Cisco Systems India Pvt Ltd SEZ Unit, Cessna Business Park, Sarjapur Marathahalli ORR, Bangalore, Karnataka 560103 India EMail: akarmaka@cisco.com