Mobile Ad hoc Networking (MANET)                              U. Herberg
Internet-Draft                           Fujitsu Laboratories of America
Obsoletes: 6622 (if approved)                                 T. Clausen
Intended status: Standards Track                LIX, Ecole Polytechnique
Expires: October 17, 2013                                    C. Dearlove
                                                         BAE Systems ATC
                                                          April 15, 2013


          Integrity Check Value and Timestamp TLV Definitions
                  for Mobile Ad Hoc Networks (MANETs)
                    draft-ietf-manet-rfc6622-bis-02

Abstract

   This document revises, extends and replaces RFC 6622.  It describes
   general and flexible TLVs for representing cryptographic Integrity
   Check Values (ICVs) and timestamps, using the generalized Mobile Ad
   Hoc Network (MANET) packet/message format defined in RFC 5444.  It
   defines two Packet TLVs, two Message TLVs, and two Address Block TLVs
   for affixing ICVs and timestamps to a packet, a message, and one or
   more addresses, respectively.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on October 17, 2013.

Copyright Notice

   Copyright (c) 2013 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



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   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 Simplified BSD License.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Differences from RFC6622 . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  Applicability Statement  . . . . . . . . . . . . . . . . . . .  4
   4.  Security Architecture  . . . . . . . . . . . . . . . . . . . .  5
   5.  Overview and Functioning . . . . . . . . . . . . . . . . . . .  6
   6.  General ICV TLV Structure  . . . . . . . . . . . . . . . . . .  7
   7.  General Timestamp TLV Structure  . . . . . . . . . . . . . . .  7
   8.  Packet TLVs  . . . . . . . . . . . . . . . . . . . . . . . . .  8
     8.1.  ICV Packet TLV . . . . . . . . . . . . . . . . . . . . . .  8
     8.2.  TIMESTAMP Packet TLV . . . . . . . . . . . . . . . . . . .  9
   9.  Message TLVs . . . . . . . . . . . . . . . . . . . . . . . . .  9
     9.1.  ICV Message TLV  . . . . . . . . . . . . . . . . . . . . .  9
     9.2.  TIMESTAMP Message TLV  . . . . . . . . . . . . . . . . . .  9
   10. Address Block TLVs . . . . . . . . . . . . . . . . . . . . . . 10
     10.1. ICV Address Block TLV  . . . . . . . . . . . . . . . . . . 10
     10.2. TIMESTAMP Address Block TLV  . . . . . . . . . . . . . . . 10
   11. ICV: Basic . . . . . . . . . . . . . . . . . . . . . . . . . . 10
   12. ICV: Hash Function and Cryptographic Function  . . . . . . . . 11
     12.1. General ICV TLV Structure  . . . . . . . . . . . . . . . . 11
       12.1.1.  Rationale . . . . . . . . . . . . . . . . . . . . . . 12
     12.2. Considerations for Calculating the ICV . . . . . . . . . . 13
       12.2.1.  Packet ICV TLV  . . . . . . . . . . . . . . . . . . . 13
       12.2.2.  Message ICV TLV . . . . . . . . . . . . . . . . . . . 13
       12.2.3.  Address Block ICV TLV . . . . . . . . . . . . . . . . 14
     12.3. Example of a Message Including an ICV  . . . . . . . . . . 14
   13. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 15
     13.1. Expert Review: Evaluation Guidelines . . . . . . . . . . . 16
     13.2. Packet TLV Type Registrations  . . . . . . . . . . . . . . 16
     13.3. Message TLV Type Registrations . . . . . . . . . . . . . . 18
     13.4. Address Block TLV Type Registrations . . . . . . . . . . . 19
     13.5. Hash Functions . . . . . . . . . . . . . . . . . . . . . . 20
     13.6. Cryptographic Functions  . . . . . . . . . . . . . . . . . 20
   14. Security Considerations  . . . . . . . . . . . . . . . . . . . 21
   15. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 21
   16. References . . . . . . . . . . . . . . . . . . . . . . . . . . 22
     16.1. Normative References . . . . . . . . . . . . . . . . . . . 22
     16.2. Informative References . . . . . . . . . . . . . . . . . . 23




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1.  Introduction

   This document specifies a syntactical representation of security-
   related information for use with [RFC5444] addresses, messages, and
   packets, and also reports and updates IANA registrations (from
   [RFC6622]) of TLV types and type extension registries for these TLV
   types.  This specification does not represent a stand-alone protocol,
   but is intended for use by MANET routing protocols, or security
   extensions thereof.

   Specifically, this document, which revises, extends and replaces
   [RFC6622], specifies:

   o  Two kinds of TLV: one for carrying Integrity Check Values (ICVs)
      and one for timestamps in packets, messages, and address blocks as
      defined by [RFC5444].

   o  A generic framework for use of these TLVs, accounting for specific
      features of Packet, Message and Address Block TLVs.

   This document retains the IANA registries, defined in [RFC6622], for
   recording code points for ICV calculations, and requests an
   additional allocation from each these registries.  This document
   retains the IANA registries, defined in [RFC6622], for recording code
   points for timestamps, hash-functions, and cryptographic functions,
   but does not request any additional allocations from these
   registries.

   Moreover, in Section 12, this document defines the following:

   o  A method for generating ICVs using a combination of a
      cryptographic function and a hash function, and for including such
      ICVs in the value field of a TLV.

1.1.  Differences from RFC6622

   This document obsoletes [RFC6622].  In addition to editorial updates,
   this document adds a new type extension 2 for the ICV TLV that is
   specified in Section 12 of this document.  It also makes it clear
   that an ICV TLV may be used to carry a truncated ICV, and that a
   single- or multi- value ICV or TIMESTAMP Address Block TLV may cover
   more than one address.

   The TLV value of an ICV TLV with type extension 2 has the same
   internal structure as an ICV TLV with type extension 1, but is
   calculated also over the source address of the IP datagram carrying
   the packet, message, or Address Block.  The rationale for adding this
   type extension is that some MANET protocols, such as [RFC6130], use



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   the IP source address of the IP datagram carrying the packet, message
   or Address Block, e.g., to identify links with neighbor routers.  If
   this address is not otherwise contained in the packet, message, or
   Address Block payload (which is permitted, e.g., in [RFC6130]), then
   the address is not protected against tampering.

2.  Terminology

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

   This document uses the terminology and notation defined in [RFC5444].
   In particular, the following TLV fields and notation from [RFC5444]
   are used in this specification:

   <msg-hop-limit>  is the hop limit of a message, as specified in
      Section 5.2 of [RFC5444].

   <msg-hop-count>  is the hop count of a message, as specified in
      Section 5.2 of [RFC5444].

   <length>  is the length of the value field in a TLV in octets, as
      specified in Section 5.4.1 of [RFC5444].

   single-length  is the length of a single value in the value field in
      a TLV in octets, as specified in Section 5.4.1 of [RFC5444].  (It
      is equal to <length> except in a multivalue Address Block TLV.)

3.  Applicability Statement

   MANET routing protocols using the format defined in [RFC5444] are
   accorded the ability to carry additional information in control
   messages and packets, through the inclusion of TLVs.  Information so
   included MAY be used by a MANET routing protocol, or by an extension
   of a MANET routing protocol, according to its specification.

   This document specifies how to include an ICV for a packet, a
   message, and addresses in Address Blocks within a message, using such
   TLVs.  This document also specifies how to treat an empty Packet TLV
   Block, and "mutable" fields, specifically the <msg-hop-count> and
   <msg-hop-limit> fields, if present in the Message Header when
   calculating ICVs, such that the resulting ICV can be correctly
   verified by any recipient.

   This document describes a generic framework for creating ICVs, and
   how to include these ICVs in TLVs.  In Section 12, an example method



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   for calculating such ICVs is given, using a cryptographic function
   and a hash function, for which two TLV type extensions are allocated.

4.  Security Architecture

   MANET routing protocol specifications may have a clause allowing a
   control message to be rejected as "badly formed" or "insecure" prior
   to the message being processed or forwarded.  In particular, MANET
   routing protocols such as the Neighborhood Discovery Protocol (NHDP)
   [RFC6130] and the Optimized Link State Routing Protocol version 2
   [OLSRv2] recognize external reasons (such as failure to verify an
   ICV) for rejecting a message that would be considered "invalid for
   processing".

   This architecture is a result of the observation that with respect to
   security in MANETs, "one size rarely fits all" and that MANET routing
   protocol deployment domains have varying security requirements
   ranging from "unbreakable" to "virtually none".  The virtue of this
   approach is that MANET routing protocol specifications (and
   implementations) can remain "generic", with extensions providing
   proper security mechanisms specific to a deployment domain.

   The MANET routing protocol "security architecture", in which this
   specification situates itself, can therefore be summarized as
   follows:

   o  MANET routing protocol specifications, each with a clause allowing
      an extension to reject a message (prior to processing/forwarding)
      as "badly formed" or "insecure".

   o  MANET routing protocol security extensions, each rejecting
      messages as "badly formed" or "insecure", as appropriate for a
      given security requirement specific to a deployment domain.

   o  Code points and an exchange format for information, necessary for
      specification of such MANET routing protocol security extensions.

   This document addresses the last of the points above, by specifying a
   common exchange format for cryptographic ICVs and timestamps, making
   reservations from within the Packet TLV, Message TLV, and Address
   Block TLV registries of [RFC5444], to be used by (and shared among)
   MANET routing protocol security extensions.

   For the specific decomposition of an ICV using a cryptographic
   function and a hash function (specified in Section 12), this document
   reports the two IANA registries from [RFC6622] for code points for
   hash functions and cryptographic functions.




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   With respect to [RFC5444], this document is:

   o  Intended to be used in the non-normative, but intended, mode of
      use described in Appendix B of [RFC5444].

   o  A specific example of the Security Considerations section of
      [RFC5444] (the authentication part).

5.  Overview and Functioning

   This document specifies a syntactical representation of security-
   related information for use with [RFC5444] addresses, messages, and
   packets, and also reports and updates IANA registrations (from
   [RFC6622]) of TLV types and type extension registries for these TLV
   types.

   Moreover, this document provides guidelines for how MANET routing
   protocols, and MANET routing protocol extensions using this
   specification, should treat ICV and Timestamp TLVs, and mutable
   fields in messages.  This specification does not represent a stand-
   alone protocol.  MANET routing protocols, and MANET routing protocol
   extensions using this specification, MUST provide instructions as to
   how to handle packets, messages, and addresses with security
   information, associated as specified in this document.

   This document reports previously assigned TLV types (from [RFC6622])
   from the registries defined for Packet, Message, and Address Block
   TLVs in [RFC5444].  When a TLV type is assigned from one of these
   registries, a registry for type extensions for that TLV type is
   created by IANA.  This document reports and updates these type
   extension registries, in order to specify internal structure (and
   accompanying processing) of the <value> field of a TLV.

   For example, and as reported in this document, an ICV TLV with type
   extension = 0 specifies that the <value> field has no pre-defined
   internal structure but is simply a sequence of octets.  An ICV TLV
   with type extension = 1 specifies that the <value> field has a pre-
   defined internal structure and defines its interpretation.  An ICV
   TLV with type extension = 2 specifies a modified version of this
   definition.

   Specifically, with type extension = 1 or type extension = 2 (added in
   this document), the <value> field contains the result of combining a
   cryptographic function and a hash function, calculated over the
   contents of the packet, message or Address Block.  The <value> field
   contains multiple sub-fields indicating which hash function and
   cryptographic function have been used as specified in Section 12.
   The difference between the two type extensions is that the ICV TLV



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   with type extension = 2 is calculated also over the source address of
   the IP datagram carrying the packet, message, or address block.

   Other documents can request assignments for other type extensions; if
   they do so, they MUST specify their internal structure (if any) and
   interpretation.

6.  General ICV TLV Structure

   The value of the ICV TLV is:

      <value> := <ICV-value>+

   where:

   <ICV-value>  is a field, of length <length> octets (except in a
      multivalue Address Block TLV, where each <ICV-value> is of length
      single-length octets) that contains the information to be
      interpreted by the ICV verification process, as specified by the
      type extension.

   Note that this does not specify how to calculate the <ICV-value> nor
   the internal structure thereof, if any; such information MUST be
   specified by the type extension for the ICV TLV type; see Section 13.
   This document specifies three such type extensions -- one for ICVs
   without pre-defined structures, and two for ICVs constructed
   combining a cryptographic function and a hash function.

7.  General Timestamp TLV Structure

   The value of the Timestamp TLV is:

      <value> := <time-value>+

   where:

   <time-value>  is a field, of length <length> octets (except in a
      multivalue Address Block TLV, where each <time-value> is of length
      single-length octets) that contains the timestamp.

   Note that this does not specify how to calculate the <time-value> nor
   the internal structure thereof, if any; such information MUST be
   specified by the type extension for the TIMESTAMP TLV type; see
   Section 13.

   A timestamp is essentially "freshness information".  As such, its
   setting and interpretation are to be determined by the MANET routing
   protocol, or MANET routing protocol extension, that uses the



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   timestamp and can, for example, correspond to a POSIX timestamp, GPS
   timestamp, or a simple sequence number.  Note that insuring time
   synchronization in a MANET may be difficult because of the
   decentralized architecture as well as highly dynamic topology due to
   mobility or other factors.  It is out of scope for this document to
   specify a time synchronization mechanism.

8.  Packet TLVs

   Two Packet TLVs are defined: one for including the cryptographic ICV
   of a packet and one for including the timestamp indicating the time
   at which the cryptographic ICV was calculated.

8.1.  ICV Packet TLV

   An ICV Packet TLV is an example of an ICV TLV as described in
   Section 6.  When determining the <ICV-value> for a packet, and adding
   an ICV Packet TLV to a packet, the following considerations MUST be
   applied:

   o  Because packets as defined in [RFC5444] are never forwarded by
      routers, no special considerations are required regarding mutable
      fields (i.e., <msg-hop-count> and <msg-hop-limit>), if present
      within any messages in the packet, when calculating the ICV.

   o  Any Packet ICV TLVs already present in the Packet TLV Block MUST
      be removed before calculating the ICV, and the Packet TLV Block
      size MUST be recalculated accordingly.

   o  If the Packet TLV Block now contains no Packet TLVs, the Packet
      TLV Block MUST be removed, and the phastlv bit in the <pkt-flags>
      field in the Packet Header MUST be cleared ('0').

   o  Any removed ICV Packet TLVs MUST be restored after having
      calculated the ICV, and the Packet TLV Block size MUST be
      recalculated accordingly.

   o  When any removed ICV Packet TLVs, and the newly calculated ICV
      Packet TLV, are added to the packet, if there is no Packet TLV
      Block then one MUST be added, including setting ('1') the phastlv
      bit in the <pkt-flags> field in the Packet Header.

   The rationale for removing any Packet ICV TLVs already present prior
   to calculating the ICV is that several ICV TLVs may be added to the
   same packet, e.g., using different ICV cryptographic and/or hash
   functions.  The rationale for removing an empty Packet TLV Block is
   because the receiver of the packet cannot tell the difference between
   what was an absent Packet TLV Block, and what was an empty Packet TLV



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   Block when removing and verifying the ICV Packet TLV if no other
   Packet TLVs are present.

8.2.  TIMESTAMP Packet TLV

   A TIMESTAMP Packet TLV is an example of a Timestamp TLV as described
   in Section 7.  If a packet contains one or more TIMESTAMP TLVs and
   one or more ICV TLVs, then the TIMESTAMP TLVs (as well as any other
   Packet TLVs) MUST be added to the packet before the ICV TLVs, in
   order to include the timestamps and other TLVs in the calculation of
   the ICVs.

9.  Message TLVs

   Two Message TLVs are defined: one for including the cryptographic ICV
   of a message and one for including the timestamp indicating the time
   at which the cryptographic ICV was calculated.

9.1.  ICV Message TLV

   An ICV Message TLV is an example of an ICV TLV as described in
   Section 6.  When determining the <ICV-value> for a message, the
   following considerations MUST be applied:

   o  The fields <msg-hop-limit> and <msg-hop-count>, if present in the
      Message Header, MUST both be assumed to have the value 0 (zero)
      when calculating the ICV.

   o  Any Message ICV TLVs already present in the Message TLV Block MUST
      be removed before calculating the ICV, and the message size as
      well as the Message TLV Block size MUST be recalculated
      accordingly.  Also, all relevant TLVs other than ICV TLVs MUST be
      added prior to TCV value calculation.

   o  Any removed ICV Message TLVs MUST be restored after having
      calculated the ICV, and the message size as well as the Message
      TLV Block size MUST be recalculated accordingly.

   The rationale for removing any ICV Message TLVs already present prior
   to calculating the ICV is that several ICV TLVs may be added to the
   same message, e.g., using different ICV cryptographic and/or hash
   functions.

9.2.  TIMESTAMP Message TLV

   A TIMESTAMP Message TLV is an example of a Timestamp TLV as described
   in Section 7.  If a message contains one or more TIMESTAMP TLVs and
   one or more ICV TLVs, then the TIMESTAMP TLVs (as well as any other



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   Message TLVs) MUST be added to the message before the ICV TLVs, in
   order to include the timestamps and other Message TLVs in the
   calculation of the ICV.

10.  Address Block TLVs

   Two Address Block TLVs are defined: one for associating a
   cryptographic ICV to one or more addresses and their associated
   information, and one for including the timestamp indicating the time
   at which the cryptographic ICV was calculated.

10.1.  ICV Address Block TLV

   An ICV Address Block TLV is an example of an ICV TLV as described in
   Section 6.  The ICV is calculated over one or more addresses,
   concatenated with any other values -- for example, other Address
   Block TLV <value> fields -- associated with those addresses.  A MANET
   routing protocol, or MANET routing protocol extension, using Address
   Block ICV TLVs MUST specify how to include any such concatenated
   attributes of the addresses in the calculation and verification
   processes for the ICV.  When determining an <ICV-value> for one or
   more addresses, the following consideration MUST be applied:

   o  If other TLV values are concatenated with the addresses for
      calculating the ICV, the corresponding TLVs MUST NOT be ICV
      Address Block TLVs already associated with any of the addresses.

   The rationale for not concatenating the addresses with any ICV TLV
   values already associated with the addresses when calculating the ICV
   is that several ICVs may be added to the same address or addresses,
   e.g., using different ICV cryptographic and/or hash functions, and
   the order of addition is not known to the recipient.

10.2.  TIMESTAMP Address Block TLV

   A TIMESTAMP Address Block TLV is an example of a Timestamp TLV as
   described in Section 7.  If one or more TIMESTAMP TLVs and one or
   more ICV TLVs are associated with an address, the relevant TIMESTAMP
   TLV <time-value>(s) MUST be included before calculating the value of
   the ICV to be contained in the ICV TLV value (i.e., concatenated with
   the associated addresses and any other values as described in
   Section 10.1).

11.  ICV: Basic

   The basic ICV, represented by way of an ICV TLV with type extension =
   0, is a simple bit-field containing the cryptographic ICV.  This
   assumes that the mechanism stipulating how ICVs are calculated and



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   verified is established outside of this specification, e.g., by
   administrative configuration or external out-of-band signaling.
   Thus, the <ICV-value>, when using type extension = 0, is:

      <ICV-value> := <ICV-data>

   where:

   <ICV-data>  is a field, of length <length> octets (or single-length
      octets in a multivalue Address Block TLV) that contains the
      cryptographic ICV.

12.  ICV: Hash Function and Cryptographic Function

   One common way of calculating an ICV is combining a cryptographic
   function and a hash function applied to the content.  This
   decomposition is specified in this section, using either type
   extension = 1 or type extension = 2, in the ICV TLVs.

12.1.  General ICV TLV Structure

   The following data structure allows representation of a cryptographic
   ICV, including specification of the appropriate hash function and
   cryptographic function used for calculating the ICV:

      <ICV-value> := <hash-function>
                     <cryptographic-function>
                     <key-id-length>
                     <key-id>?
                     <ICV-data>

   where:

   <hash-function>  is a one octet unsigned integer field specifying the
      hash function.

   <cryptographic-function>  is a one octet unsigned integer field
      specifying the cryptographic function.

   <key-id-length>  is a one octet unsigned integer field specifying the
      length of the <key-id> field as a number of octets.  The value
      zero (0x00) is reserved for using a single pre-installed, shared
      key.

   <key-id>  is a field specifying the key identifier of the key that
      was used to calculate the ICV of the message, which allows unique
      identification of different keys with the same originator.  It is
      the responsibility of each key originator to make sure that



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      actively used keys that it issues have distinct key identifiers.
      If <key-id-length> equals zero (0x00), the <key-id> field is not
      contained in the TLV, and a single pre-installed, shared key is
      used.

   <ICV-data>  is a field with length <length> - 3 - <key-id-length>
      octets (except in a multivalue Address Block TLV, in which it is
      single-length - 3 - <key-id-length> octets) and which contains the
      cryptographic ICV.

   The version of this TLV, specified in this section, assumes that,
   unless otherwise specified, calculating the ICV can be decomposed
   into:

      ICV-value = cryptographic-function(hash-function(content))

   In some cases a different combination of cryptographic function and
   hash function may be specified.  This is the case for the HMAC
   function, which is specified as defined in Section 13.6, using the
   hash function twice.

   The difference between the two type extensions is that in addition to
   the information covered by the ICV using type extension 1 (which is
   detailed in the following sections), the ICV using type extension 2
   also MUST cover the source address of the IP datagram carrying the
   corresponding packet, message, or Address Block.

   The <ICV-data> field MAY be truncated after being calculated, this is
   indicated by its length, calculated as described above.  The
   truncation SHOULD be as specified for the relevant cryptographic
   function (and, if appropriate, hash function).

   The hash function and the cryptographic function correspond to the
   entries in two IANA registries, which are reported by this
   specification and are described in Section 13.

12.1.1.  Rationale

   The rationale for separating the hash function and the cryptographic
   function into two octets instead of having all combinations in a
   single octet -- possibly as a TLV type extension -- is that adding
   further hash functions or cryptographic functions in the future may
   lead to a non-contiguous number space, as well as providing a smaller
   overall space.

   The rationale for not including a field that lists parameters of the
   cryptographic ICV in the TLV is that, before being able to validate a
   cryptographic ICV, routers have to exchange or acquire keys.  Any



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   additional parameters can be provided together with the keys in that
   bootstrap process.  It is therefore not necessary, and would even
   entail an extra overhead, to transmit the parameters within every
   message.

   The rationale for the addition of type extension 2 is that the source
   code address is used in some cases, such as when processing HELLO
   messages in [RFC6130].  This is applicable only to packets (which
   only ever travel one hop) and messages (and their Address Blocks)
   that only travel one hop.  It is not applicable to messages that may
   be forwarded more than one hop, such as TC messages in [OLSRv2].

12.2.  Considerations for Calculating the ICV

   The considerations listed in the following subsections MUST be
   applied when calculating the ICV for Packet, Message, and Address
   Block TLVs, respectively.

12.2.1.  Packet ICV TLV

   When determining the <ICV-data> for a packet, with type extension =
   1:

   o  The ICV is calculated over the fields <hash-function>,
      <cryptographic-function>, <key-id-length>, and -- if present --
      <key-id> (in that order), followed by the entire packet, including
      the Packet Header, including all Packet TLVs (other than ICV
      Packet TLVs), and all included messages.  The considerations of
      Section 8.1 MUST be applied.

   When determining the <ICV-data> for a packet, with type extension =
   2:

   o  The same procedure as for type extension = 1 is used, except that
      the source address of the IP datagram carrying the packet is also
      concatenated, in the first position, with the data used.

12.2.2.  Message ICV TLV

   When determining the <ICV-data> for a message, with type extension =
   1:

   o  The ICV is calculated over the fields <hash-function>,
      <cryptographic-function>, <key-id-length>, and -- if present --
      <key-id> (in that order), followed by the entire message.  The
      considerations in Section 9.1 MUST be applied.

   When determining the <ICV-data> for a message, with type extension =



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   2:

   o  The same procedure as for type extension = 1 is used, except that
      the source address of the IP datagram carrying the message is also
      concatenated, in the first position, with the data used.

12.2.3.  Address Block ICV TLV

   When determining the <ICV-data> for one or more addresses, with type
   extension = 1:

   o  The ICV is calculated over the fields <hash-function>,
      <cryptographic-function>, <key-id-length>, and -- if present --
      <key-id> (in that order), followed by the addresses, and followed
      by any other values -- for example, other address block TLV
      <value>s that are associated with those addresses.  A MANET
      routing protocol, or MANET routing protocol extension, using ICV
      Address Block TLVs MUST specify how to include any such
      concatenated attribute of the addresses in the verification
      process of the ICV.  The considerations in Section 10.1 MUST be
      applied.

   When determining the <ICV-data> for one or more addresses, with type
   extension = 2:

   o  The same procedure as for type extension = 1 is used, except that
      the source address of the IP datagram carrying the Address Block
      is also concatenated, in the first position, with the data used.

12.3.  Example of a Message Including an ICV

   The sample message depicted in Figure 1 is derived from Appendix D of
   [RFC5444].  The message contains an ICV Message TLV, with the value
   representing an ICV that is 16 octets long of the whole message, and
   a key identifier that is 4 octets long.  The type extension of the
   Message TLV is 1, for the specific decomposition of an ICV using a
   cryptographic function and a hash function, as specified in
   Section 12.













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      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | PV=0 |  PF=8  |    Packet Sequence Number     | Message Type  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | MF=15 | MAL=3 |      Message Length = 44      | Msg Orig Addr |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |       Message Originator Address (cont)       |   Hop Limit   |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Hop Count   |    Message Sequence Number    | Msg TLV Block |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | Length = 27   |     ICV       |  MTLVF = 144  |  MTLVExt = 1  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |Value Len = 23 |   Hash Func   |  Crypto Func  |Key ID length=4|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Key Identifier                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          ICV Value                            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          ICV Value (cont)                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          ICV Value (cont)                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          ICV Value (cont)                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 1: Example Message with ICV

13.  IANA Considerations

   This specification reports the following, originally specified in
   [RFC6622]:

   o  Two Packet TLV Types, which have been allocated from the 0-223
      range of the "Packet TLV Types" repository of [RFC5444], as
      specified in Table 1.

   o  Two Message TLV Types, which have been allocated from the 0-127
      range of the "Message TLV Types" repository of [RFC5444], as
      specified in Table 2.

   o  Two Address Block TLV Types, which have been allocated from the
      0-127 range of the "Address Block TLV Types" repository of
      [RFC5444], as specified in Table 3.

   This specification updates the following, created in [RFC6622]:





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   o  A type extension registry for each of these TLV types with values
      as listed in Tables 1, 2, and 3.

   The following terms are used as defined in [BCP26]: "Namespace",
   "Registration", and "Designated Expert".

   The following policy is used as defined in [BCP26]: "Expert Review".

13.1.  Expert Review: Evaluation Guidelines

   For TLV type extensions registries where an Expert Review is
   required, the Designated Expert SHOULD take the same general
   recommendations into consideration as those specified by [RFC5444].

   For both Timestamp and ICV TLVs, functionally similar extensions for
   Packet, Message, and Address Block TLVs SHOULD be numbered
   identically.

13.2.  Packet TLV Type Registrations

   IANA has, in accordance with [RFC6622], made allocations from the
   "Packet TLV Types" namespace of [RFC5444] for the Packet TLVs
   specified in Table 1.  IANA are requested to modify this allocation
   (defining type extension = 2) as indicated.



























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   +-----------+------+-----------+------------------------------------+
   |    Name   | Type |    Type   |             Description            |
   |           |      | Extension |                                    |
   +-----------+------+-----------+------------------------------------+
   |    ICV    |   5  |     0     |           ICV of a packet          |
   |           |      |     1     |     ICV, using a cryptographic     |
   |           |      |           |  function and a hash function, as  |
   |           |      |           |   specified in Section 12 of this  |
   |           |      |           |              document              |
   |           |      |     2     |     ICV, using a cryptographic     |
   |           |      |           |  function and a hash function, and |
   |           |      |           |  including the IP datagram source  |
   |           |      |           |      address, as specified in      |
   |           |      |           |     Section 12 of this document    |
   |           |      |   3-251   |      Unassigned; Expert Review     |
   |           |      |  252-255  |          Experimental Use          |
   | TIMESTAMP |   6  |     0     |   Unsigned timestamp of arbitrary  |
   |           |      |           |   length, given by the TLV Length  |
   |           |      |           | field.  The MANET routing protocol |
   |           |      |           |   has to define how to interpret   |
   |           |      |           |           this timestamp           |
   |           |      |     1     |    Unsigned 32-bit timestamp, as   |
   |           |      |           |   specified in [IEEE 1003.1-2008   |
   |           |      |           |              (POSIX)]              |
   |           |      |     2     | NTP timestamp format, as specified |
   |           |      |           |            in [RFC5905]            |
   |           |      |     3     |    Signed timestamp of arbitrary   |
   |           |      |           | length with no constraints such as |
   |           |      |           |  monotonicity.  In particular, it  |
   |           |      |           |   may represent any random value   |
   |           |      |   4-251   |      Unassigned; Expert Review     |
   |           |      |  252-255  |          Experimental Use          |
   +-----------+------+-----------+------------------------------------+

                         Table 1: Packet TLV Types

   More than one ICV Packet TLV with the same type extension MAY be
   included in a packet if these represent different ICV calculations
   (e.g., with type extension 1 or 2 and different cryptographic
   function and/or hash function, or with a different key identifier).
   ICV Packet TLVs that carry what is declared to be the same
   information MUST NOT be included in the same packet.  More than one
   TIMESTAMP Packet TLV with the same type extension MUST NOT be
   included in a packet.







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13.3.  Message TLV Type Registrations

   IANA has, in accordance with [RFC6622], made allocations from the
   "Message TLV Types" namespace of [RFC5444] for the Message TLVs
   specified in Table 2.  IANA are requested to modify this allocation
   (defining type extension = 2) as indicated.

   +-----------+------+-----------+------------------------------------+
   |    Name   | Type |    Type   |             Description            |
   |           |      | Extension |                                    |
   +-----------+------+-----------+------------------------------------+
   |    ICV    |   5  |     0     |          ICV of a message          |
   |           |      |     1     |     ICV, using a cryptographic     |
   |           |      |           |  function and a hash function, as  |
   |           |      |           |   specified in Section 12 of this  |
   |           |      |           |              document              |
   |           |      |     2     |     ICV, using a cryptographic     |
   |           |      |           |  function and a hash function, and |
   |           |      |           |  including the IP datagram source  |
   |           |      |           |      address, as specified in      |
   |           |      |           |     Section 12 of this document    |
   |           |      |   3-251   |      Unassigned; Expert Review     |
   |           |      |  252-255  |          Experimental Use          |
   | TIMESTAMP |   6  |     0     |   Unsigned timestamp of arbitrary  |
   |           |      |           |   length, given by the TLV Length  |
   |           |      |           |               field.               |
   |           |      |     1     |    Unsigned 32-bit timestamp, as   |
   |           |      |           |   specified in [IEEE 1003.1-2008   |
   |           |      |           |              (POSIX)]              |
   |           |      |     2     | NTP timestamp format, as specified |
   |           |      |           |            in [RFC5905]            |
   |           |      |     3     |    Signed timestamp of arbitrary   |
   |           |      |           | length with no constraints such as |
   |           |      |           |  monotonicity.  In particular, it  |
   |           |      |           |   may represent any random value   |
   |           |      |   4-251   |      Unassigned; Expert Review     |
   |           |      |  252-255  |          Experimental Use          |
   +-----------+------+-----------+------------------------------------+

                        Table 2: Message TLV Types

   More than one ICV Message TLV with the same type extension MAY be
   included in a message if these represent different ICV calculations
   (e.g., with type extension 1 or 2 and different cryptographic
   function and/or hash function, or with a different key identifier).
   ICV Message TLVs that carry what is declared to be the same
   information MUST NOT be included in the same message.  More than one
   TIMESTAMP Message TLV with the same type extension MUST NOT be



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   included in a message.

13.4.  Address Block TLV Type Registrations

   IANA has, in accordance with [RFC6622], made allocations from the
   "Address Block TLV Types" namespace of [RFC5444] for the Packet TLVs
   specified in Table 3.  IANA are requested to modify this allocation
   (defining type extension = 2) as indicated.

   +-----------+------+-----------+------------------------------------+
   |    Name   | Type |    Type   |             Description            |
   |           |      | Extension |                                    |
   +-----------+------+-----------+------------------------------------+
   |    ICV    |   5  |     0     |     ICV of an object (e.g., an     |
   |           |      |           |              address)              |
   |           |      |     1     |     ICV, using a cryptographic     |
   |           |      |           |  function and a hash function, as  |
   |           |      |           |   specified in Section 12 of this  |
   |           |      |           |              document              |
   |           |      |     2     |     ICV, using a cryptographic     |
   |           |      |           |  function and a hash function, and |
   |           |      |           |  including the IP datagram source  |
   |           |      |           |      address, as specified in      |
   |           |      |           |     Section 12 of this document    |
   |           |      |   3-251   |      Unassigned; Expert Review     |
   |           |      |  252-255  |          Experimental Use          |
   | TIMESTAMP |   6  |     0     |   Unsigned timestamp of arbitrary  |
   |           |      |           |   length, given by the TLV Length  |
   |           |      |           |                field               |
   |           |      |     1     |    Unsigned 32-bit timestamp, as   |
   |           |      |           |   specified in [IEEE 1003.1-2008   |
   |           |      |           |              (POSIX)]              |
   |           |      |     2     | NTP timestamp format, as specified |
   |           |      |           |            in [RFC5905]            |
   |           |      |     3     |    Signed timestamp of arbitrary   |
   |           |      |           | length with no constraints such as |
   |           |      |           |  monotonicity.  In particular, it  |
   |           |      |           |   may represent any random value   |
   |           |      |   4-251   |      Unassigned; Expert Review     |
   |           |      |  252-255  |          Experimental Use          |
   +-----------+------+-----------+------------------------------------+

                     Table 3: Address Block TLV Types

   More than one ICV Address Block TLV with the same type extension MAY
   be associate with an address if these represent different ICV
   calculations (e.g., with type extension 1 or 2 and different
   cryptographic function and/or hash function, or with a different key



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   identifier).  ICV Address Block TLVs that carry what is declared to
   be the same information MUST NOT be associated with the same address.
   More than one TIMESTAMP Address Block TLV with the same type
   extension MUST NOT be associated with any address.

13.5.  Hash Functions

   IANA has, in accordance with [RFC6622], created a registry for hash
   functions that can be used when creating an ICV, as specified in
   Section 12 of this document.  The initial assignments and allocation
   policies are specified in Table 4.  This registry is unchanged by
   this specification.

   +-------------+-----------+-----------------------------------------+
   |     Hash    | Algorithm |               Description               |
   |   Function  |           |                                         |
   |    Value    |           |                                         |
   +-------------+-----------+-----------------------------------------+
   |      0      |    none   | The "identity function": The hash value |
   |             |           |    of an object is the object itself    |
   |      1      |    SHA1   |            [NIST-FIPS-180-4]            |
   |      2      |   SHA224  |            [NIST-FIPS-180-4]            |
   |      3      |   SHA256  |            [NIST-FIPS-180-4]            |
   |      4      |   SHA384  |            [NIST-FIPS-180-4]            |
   |      5      |   SHA512  |            [NIST-FIPS-180-4]            |
   |    6-251    |           |        Unassigned; Expert Review        |
   |   252-255   |           |             Experimental Use            |
   +-------------+-----------+-----------------------------------------+

                      Table 4: Hash Function Registry

13.6.  Cryptographic Functions

   IANA has, in accordance with [RFC6622], created a registry for the
   cryptographic functions, as specified in Section 12 of this document.
   Initial assignments and allocation policies are specified in Table 5.
   This registry is unchanged by this specification.














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   +----------------+-----------+--------------------------------------+
   |  Cryptographic | Algorithm |              Description             |
   | Function Value |           |                                      |
   +----------------+-----------+--------------------------------------+
   |        0       |    none   |  The "identity function": The value  |
   |                |           |   of an encrypted hash is the hash   |
   |                |           |                itself                |
   |        1       |    RSA    |               [RFC3447]              |
   |        2       |    DSA    |           [NIST-FIPS-186-3]          |
   |        3       |    HMAC   |               [RFC2104]              |
   |        4       |    3DES   |           [NIST-SP-800-67]           |
   |        5       |    AES    |            [NIST-FIPS-197]           |
   |        6       |   ECDSA   |           [ANSI-X9-62-2005]          |
   |      7-251     |           |       Unassigned; Expert Review      |
   |     252-255    |           |           Experimental Use           |
   +----------------+-----------+--------------------------------------+

                 Table 5: Cryptographic Function Registry

14.  Security Considerations

   This document does not specify a protocol.  It provides a syntactical
   component for cryptographic ICVs of messages and packets, as defined
   in [RFC5444].  It can be used to address security issues of a MANET
   routing protocol or MANET routing protocol extension.  As such, it
   has the same security considerations as [RFC5444].

   In addition, a MANET routing protocol or MANET routing protocol
   extension that uses this specification MUST specify how to use the
   framework, and the TLVs presented in this document.  In addition, the
   protection that the MANET routing protocol or MANET routing protocol
   extensions attain by using this framework MUST be described.

   As an example, a MANET routing protocol that uses this component to
   reject "badly formed" or "insecure" messages if a control message
   does not contain a valid ICV SHOULD indicate the security assumption
   that if the ICV is valid, the message is considered valid.  It also
   SHOULD indicate the security issues that are counteracted by this
   measure (e.g., link or identity spoofing) as well as the issues that
   are not counteracted (e.g., compromised keys).

15.  Acknowledgements

   The authors would like to thank Bo Berry (Cisco), Alan Cullen (BAE
   Systems), Justin Dean (NRL), Paul Lambert (Marvell), Jerome Milan
   (Ecole Polytechnique), and Henning Rogge (FGAN) for their
   constructive comments on [RFC6622].




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   The authors also appreciate the detailed reviews of [RFC6622] from
   the Area Directors, in particular Stewart Bryant (Cisco), Stephen
   Farrell (Trinity College Dublin), and Robert Sparks (Tekelec), as
   well as Donald Eastlake (Huawei) from the Security Directorate.

   The authors would like to thank Justin Dean (NRL) and Henning Rogge
   (FGAN) for their constructive comments on this specification.

16.  References

16.1.  Normative References

   [BCP26]                     Narten, T. and H. Alvestrand, "Guidelines
                               for Writing an IANA Considerations
                               Section in RFCs", BCP 26, RFC 5226,
                               May 2008.

   [RFC2119]                   Bradner, S., "Key words for use in RFCs
                               to Indicate Requirement Levels", BCP 14,
                               RFC 2119, March 1997.

   [RFC5444]                   Clausen, T., Dearlove, C., Dean, J., and
                               C. Adjih, "Generalized Mobile Ad Hoc
                               Network (MANET) Packet/Message Format",
                               RFC 5444, February 2009.

   [RFC5905]                   Mills, D., Martin, J., Ed., Burbank, J.,
                               and W. Kasch, "Network Time Protocol
                               Version 4: Protocol and Algorithms
                               Specification", RFC 5905, June 2010.

   [RFC3447]                   Jonsson, J. and B. Kaliski, "Public-Key
                               Cryptography Standards (PKCS) #1: RSA
                               Cryptography Specifications Version 2.1",
                               RFC 3447, February 2003.

   [RFC2104]                   Krawczyk, H., Bellare, M., and R.
                               Canetti, "HMAC: Keyed-Hashing for Message
                               Authentication", RFC 2104, February 1997.

   [NIST-FIPS-197]             National Institute of Standards and
                               Technology, "Specification for the
                               Advanced Encryption Standard (AES)",
                               FIPS 197, November 2001.

   [NIST-FIPS-186-3]           National Institute of Standards and
                               Technology, "Digital Signature Standard
                               (DSS)", FIPS 186-3, June 2009.



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   [ANSI-X9-62-2005]           American National Standards Institute,
                               "Public Key Cryptography for the
                               Financial Services Industry: The Elliptic
                               Curve Digital Signature Algorithm
                               (ECDSA)", ANSI X9.62-2005, November 2005.

   [NIST-SP-800-67]            National Institute of Standards and
                               Technology, "Recommendation for the
                               Triple Data Encryption Algorithm (TDEA)
                               Block Cipher", Special
                               Publication 800-67, Revision 1,
                               January 2012.

   [NIST-FIPS-180-4]           National Institute of Standards and
                               Technology, "Secure Hash Standard (SHS)",
                               FIPS 180-4, March 2012.

   [IEEE 1003.1-2008 (POSIX)]  IEEE Computer Society, "1003.1-2008
                               Standard for Information Technology -
                               Portable Operating System Interface
                               (POSIX) Base Specifications, Issue 7",
                               December 2008.

16.2.  Informative References

   [RFC6130]                   Clausen, T., Dearlove, C., and J. Dean,
                               "Mobile Ad Hoc Network (MANET)
                               Neighborhood Discovery Protocol (NHDP)",
                               RFC 6130, April 2011.

   [RFC6622]                   Herberg, U. and T. Clausen, "Integrity
                               Check Value and Timestamp TLV Definitions
                               for Mobile Ad Hoc Networks (MANETs)",
                               RFC 6622, May 2012.

   [OLSRv2]                    Clausen, T., Dearlove, C., Jacquet, P.,
                               and U. Herberg, "The Optimized Link State
                               Routing Protocol version 2", Work in
                               Progress draft-ietf-manet-olsrv2-19,
                               March 2013.











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Authors' Addresses

   Ulrich Herberg
   Fujitsu Laboratories of America
   1240 E. Arques Ave.
   Sunnyvale, CA  94085
   USA

   EMail: ulrich@herberg.name
   URI:   http://www.herberg.name/


   Thomas Heide Clausen
   LIX, Ecole Polytechnique
   91128 Palaiseau Cedex
   France

   Phone: +33 6 6058 9349
   EMail: T.Clausen@computer.org
   URI:   http://www.thomasclausen.org/


   Christopher Dearlove
   BAE Systems Advanced Technology Centre
   West Hanningfield Road
   Great Baddow, Chelmsford
   United Kingdom

   Phone: +44 1245 242194
   EMail: chris.dearlove@baesystems.com
   URI:   http://www.baesystems.com/




















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