Mobile Ad hoc Networking (MANET)                              U. Herberg
Internet-Draft                           Fujitsu Laboratories of America
Intended status: Standards Track                              T. Clausen
Expires: August 3, September 7, 2012                      LIX, Ecole Polytechnique
                                                        January 31,
                                                           March 6, 2012

             MANET Cryptographical Signature

     Integrity Check Value and Timestamp TLV Definition
                    draft-ietf-manet-packetbb-sec-08 Definitions for MANETs
                    draft-ietf-manet-packetbb-sec-09

Abstract

   This document describes general and flexible TLVs (type-length-value
   structure) for representing
   cryptographic integrity check values (ICV) (i.e. digital signatures
   or MACs) as well as timestamps, using the generalized MANET packet/message packet/
   message format defined in RFC 5444.  It defines two Packet TLVs, two
   Message TLVs, and two Address Block TLVs, for affixing cryptographic signatures ICVs and
   timestamps to a packet, message and address, respectively.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
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   This Internet-Draft will expire on August 3, September 7, 2012.

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   document authors.  All rights reserved.

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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Applicability Statement  . . . . . . . . . . . . . . . . . . .  4  3
   4.  Security Architecture  . . . . . . . . . . . . . . . . . . . .  4
   5.  Overview and Functioning . . . . . . . . . . . . . . . . . . .  5
   6.  General Signature ICV TLV Structure  . . . . . . . . . . . . . . . . . .  6
   7.  General Timestamp TLV Structure  . . . . . . . . . . . . . . .  6
   8.  Packet TLVs  . . . . . . . . . . . . . . . . . . . . . . . . .  7
     8.1.  Packet SIGNATURE ICV TLV . . . . . . . . . . . . . . . . . . . . . .  7
     8.2.  Packet TIMESTAMP TLV . . . . . . . . . . . . . . . . . . .  7
   9.  Message TLVs . . . . . . . . . . . . . . . . . . . . . . . . .  8  7
     9.1.  Message SIGNATURE ICV TLV  . . . . . . . . . . . . . . . . . .  8 . . .  7
     9.2.  Message TIMESTAMP TLV  . . . . . . . . . . . . . . . . . .  8
   10. Address Block TLVs . . . . . . . . . . . . . . . . . . . . . .  8
     10.1. Address Block SIGNATURE ICV TLV  . . . . . . . . . . . . . . .  9 . . .  8
     10.2. Address Block TIMESTAMP TLV  . . . . . . . . . . . . . . .  9
   11. Signature: ICV: Basic . . . . . . . . . . . . . . . . . . . . . . . . . .  9
   12. Signature: ICV: Cryptographic Function over a Hash Value  . . . . . 10 . . .  9
     12.1. General Signature ICV TLV Structure  . . . . . . . . . . . . . 10 . . .  9
       12.1.1.  Rationale . . . . . . . . . . . . . . . . . . . . . . 11 10
     12.2. Considerations for Calculating the Signature ICV . . . . . . . . . . 11
       12.2.1.  Packet SIGNATURE ICV TLV  . . . . . . . . . . . . . . . . . . . 11
       12.2.2.  Message SIGNATURE ICV TLV . . . . . . . . . . . . . . . . . . . 11
       12.2.3.  Address Block SIGNATURE ICV TLV . . . . . . . . . . . . . . . . 11
     12.3. Example of a Signed Message including an ICV  . . . . . . . . . . . . . . . 12 11
   13. IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 12
     13.1. Expert Review: Evaluation Guidelines . . . . . . . . . . . 13
     13.2. Packet TLV Type Registrations  . . . . . . . . . . . . . . 13 14
     13.3. Message TLV Type Registrations . . . . . . . . . . . . . . 14 15
     13.4. Address Block TLV Type Registrations . . . . . . . . . . . 15 16
     13.5. Hash Function  . . . . . . . . . . . . . . . . . . . . . . 15 17
     13.6. Cryptographic Algorithm  . . . . . . . . . . . . . . . . . 16 17
   14. Security Considerations  . . . . . . . . . . . . . . . . . . . 16 18
   15. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 16 18
   16. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17 18
     16.1. Normative References . . . . . . . . . . . . . . . . . . . 17 18
     16.2. Informative References . . . . . . . . . . . . . . . . . . 17 19
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 17 20

1.  Introduction

   This document specifies:

   o  Two TLVs for carrying cryptographic signatures integrity check values (ICV) and timestamps
      in packets, messages, and address blocks as defined by [RFC5444],

   o  A generic framework for calculating cryptographic signatures, ICVs, accounting (for Message TLVs) for
      mutable message header fields (<msg-hop-limit> and <msg-hop-count>), <msg-hop-
      count>), where these fields are present in messages.

   This document requests from IANA:

   o  Allocations for these Packet, Message, and Address Block TLVs from
      the 0-223 Packet TLV range, the 0-127 Message TLV range and the
      0-127 Address Block TLV range from [RFC5444],

   o  Creation of two sets up IANA registries for recording code points for
   hash function and signature ICV calculation, respectively.

   Finally,

   Moreover, this document defines, in Section 12:

   o  One common method for generating signatures ICVs as a cryptographic function,
      calculated over the hash value of the content to be signed.

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 from [RFC5444] are used in
   this specification:

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

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

   <length>  - length of a TLV in octets, as specified in Section 5.4.1
      of [RFC5444].

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 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 a cryptographic signature an ICV for a packet, a
   message, and addresses in address blocks within a message, by way of
   such TLVs.  This document also specifies how to treat "mutable"
   fields, specifically the <msg-hop-count> and <msg-
   hop-limit> <msg-hop-limit> fields,
   if present in the message header when calculating
   signatures, ICVs, such that the
   resulting signature ICV can be correctly verified by any recipient, and how to
   include this signature. ICV.

   This document describes a generic framework for creating signatures, ICVs, and
   how to include these signatures ICVs in TLVs.  In Section 12, an example method
   for calculating such signatures ICVs is given, using a cryptographic function
   over the hash value of the content to be signed.

4.  Security Architecture

   Basic MANET routing protocol specifications are often "oblivious to
   security", however have a clause allowing a control message to be
   rejected as "badly formed" or "insecure" prior to it being processed
   or forwarded.  MANET routing protocols such as [RFC6130] and [OLSRv2]
   recognize external reasons (such as failure to verify a signature) an ICV) for
   rejecting a message as "badly formed", message, and therefore "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 deployment-domain specific security mechanisms.

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

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

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

   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 these issues, by specifying a
   common exchange format for cryptographic signatures, ICVs, making reservations
   from within the Packet TLV, Message TLV, and Address Block TLV
   registries of [RFC5444], to be used (and shared) among MANET routing
   protocol security extensions.

   For the specific decomposition of a signature an ICV into a cryptographic
   function over a hash value, specified in Section 12, this document
   establishes two IANA registries for code-points for hash functions
   and cryptographic functions adhering to [RFC5444].

   With respect to [RFC5444], this document:

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

   o  Is 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, as well as establishes IANA registrations and registries.

   Moreover, this document provides guidelines for how MANET routing
   protocols, and MANET routing protocol extensions, using this
   specification, should treat Signature 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 requests assignment of TLV types 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 utilizes these "Type Extension" registries so created, in
   order to specify internal structure (and accompanying processing) of
   the <value> field of a TLV.

   For example, and as defined in this document, a SIGNATURE an ICV TLV with Type
   Extension = 0 specifies that the <value> field has no pre-
   defined pre-defined
   internal structure, but is simply a sequence of octets.  A
   SIGNATURE  An ICV TLV
   with Type Extension = 1 specifies that the <value> field has a pre-defined pre-
   defined internal structure, and defines its interpretation
   (specifically, the <value> field consists of a cryptographic
   operation over a hash value, with fields indicating which hash
   function and cryptographic operation has been used, specified in
   Section 12).

   Other documents can request assignments for other Type Extensions,
   and MUST, if so, specify their internal structure (if any) and
   interpretation.

6.  General Signature ICV TLV Structure

   The value of the Signature ICV TLV is:

             <value> := <signature-value> <ICV-value>

   where:

   <signature-value>

   <ICV-value>  is a field, of <length> octets, which contains the
      information, to be interpreted by the signature ICV verification process, as
      specified by the Type Extension.

   Note that this does not stipulate how to calculate the <signature-
   value>, <ICV-value>,
   nor the internal structure hereof, if any; such MUST be specified by
   way of the Type Extension for the SIGNATURE ICV TLV type, see Section 13.  This
   document specifies two such type-extensions, for signatures ICVs without pre-defined pre-
   defined structures, and for signatures ICVs constructed by way of a
   cryptographic operation over a hash-value.

7.  General Timestamp TLV Structure

   The value of the Timestamp TLV is:

          <value> := <time-value>

   where:

   <time-value>  is an unsigned integer field, of length <length>, which
      contains the timestamp.

      Note that this does not stipulate how to calculate the <time-
      value>, nor the internal structure hereof, if any; such MUST be
      specified by way of the Type Extension for the TIMESTAMP TLV type,
      see Section 13.

   A timestamp is essentially "freshness information".  As such, its
   setting and interpretation is to be determined by the MANET routing
   protocol, or MANET routing protocol extension, that uses the
   timestamp, and can, e.g., correspond to a UNIX-timestamp, GPS
   timestamp or a simple sequence number.

8.  Packet TLVs

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

8.1.  Packet SIGNATURE ICV TLV

   A Packet SIGNATURE ICV TLV is an example of a Signature an ICV TLV as described in
   Section 6.

   The following considerations apply:

   o  As packets defined in [RFC5444] are never forwarded by routers, no
      special considerations are required regarding mutable fields (e.g.
      <msg-hop-count> and <msg-hop-limit>), if present, when calculating
      the signature. ICV.

   o  Any Packet SIGNATURE ICV TLVs already present in the Packet TLV block MUST
      be removed before calculating the signature, ICV, and the Packet TLV block
      size MUST be recalculated accordingly.  Removed
      SIGNATURE ICV TLVs SHOULD MUST be
      restored after having calculated the
      signature ICV value.

   The rationale for removing any Packet SIGNATURE ICV TLV already present prior
   to calculating the signature ICV is that several signatures ICVs may be added to the same
   packet, e.g., using different signature ICV functions.

8.2.  Packet TIMESTAMP TLV

   A Packet TIMESTAMP TLV is an example of a Timestamp TLV as described
   in Section 7.  If a packet contains a TIMESTAMP TLV and a SIGNATURE an ICV TLV,
   the TIMESTAMP TLV SHOULD be added to the packet before any
   SIGNATURE ICV TLV,
   in order that it be included in the calculation of the
   signature. ICV.

9.  Message TLVs

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

9.1.  Message SIGNATURE ICV TLV

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

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

   o  Any Message SIGNATURE ICV TLVs already present in the Message TLV block MUST
      be removed before calculating the signature, ICV, and the message size as
      well as the Message TLV block size MUST be recalculated
      accordingly.  Removed SIGNATURE ICV TLVs SHOULD MUST be restored after having
      calculated the signature ICV value.

   The rationale for removing any Message SIGNATURE ICV TLV already present prior
   to calculating the signature ICV is that several signatures ICVs may be added to the same
   message, e.g., using different signature ICV functions.

9.2.  Message TIMESTAMP TLV

   A Message TIMESTAMP TLV is an example of a Timestamp TLV as described
   in Section 7.  If a message contains a TIMESTAMP TLV and a SIGNATURE an ICV TLV,
   the TIMESTAMP TLV SHOULD be added to the message before the
   SIGNATURE ICV TLV,
   in order that it be included in the calculation of the
   signature. ICV.

10.  Address Block TLVs

   Two Address Block TLVs are defined, for associating a cryptographic
   signature
   ICV to an address, and for including the timestamp indicating the
   time at which the cryptographic signature ICV was calculated.

10.1.  Address Block SIGNATURE ICV TLV

   An Address Block SIGNATURE ICV TLV is an example of a Signature an ICV TLV as described in
   Section 6.  The signature ICV is calculated over the address, concatenated with
   any other values, for example, any other
   address block Address Block TLV <value>
   fields, that is associated with that address.  A MANET routing
   protocol or MANET routing protocol extension using Address Block SIGNATURE ICV
   TLVs MUST specify how to include any such concatenated attribute of
   the address in the verification process of the signature. ICV.  When determining
   the
   <signature-value> <ICV-value> for an address, the following consideration MUST be
   applied:

   o  If other TLV values are concatenated with the address for
      calculating the signature, ICV, these TLVs MUST NOT be Address Block
      SIGNATURE ICV TLVs
      already associated with the address.

   The rationale for not concatenating the address with any SIGNATURE ICV TLV
   values already associated with the address when calculating the
   signature ICV
   is that several signatures ICVs may be added to the same address, e.g., using
   different signature ICV functions.

10.2.  Address Block TIMESTAMP TLV

   An Address Block TIMESTAMP TLV is an example of a Timestamp TLV as
   described in Section 7.  If both a TIMESTAMP TLV and a SIGNATURE an ICV TLV are
   associated with an address, the TIMESTAMP TLV <value> SHOULD MUST be
   considered covered
   when calculating the value of the signature. ICV to be contained in the ICV TLV
   value (i.e. concatenated with the associated address and any other
   values as described in Section 10.1).

11.  Signature:  ICV: Basic

   The basic signature, ICV, represented by way of a SIGNATURE an ICV TLV with Type Extension =
   0, is a simple bit-field containing the cryptographic
   signature. ICV.  This
   assumes that the mechanism stipulating how
   signatures ICVs are calculated and
   verified is established outside of this specification, e.g., by way
   of administrative configuration or external out-of-band signaling.
   Thus, the <signature-value> <ICV-value> for when using Type Extension = 0 is:

             <signature-value>

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

   where:

   <signature-data>

   <ICV-data>  is an unsigned integer field, of length <length>, which
      contains the cryptographic signature. ICV.

12.  Signature:  ICV: Cryptographic Function over a Hash Value

   One common way of calculating a signature an ICV is applying a cryptographic
   function on a hash value of the content.  This decomposition is
   specified in the following, using a Type Extension = 1 in the
   Signature ICV
   TLVs.

12.1.  General Signature ICV TLV Structure

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

             <signature-value> ICV:

                   <ICV-value> := <hash-function>
                                  <cryptographic-function>
                                  <key-index>
                                  <signature-data>
                                  <ICV-data>

   where:

   <hash-function>  is an 8-bit unsigned integer field specifying the
      hash function.

   <cryptographic-function>  is an 8-bit unsigned integer field
      specifying the cryptographic function.

   <key-index>

   <key-id-length>  is an 8-bit unsigned integer field specifying the
      length of the <key-id> field in number of octets.  The value 0x00
      is reserved for using a pre-installed, shared key.

   <key-id>  is a field specifying the key
      index identifier of the key which that
      was used to sign 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 actively
      used keys that it issues have distinct key indices and
      that all key indices have a value not equal identifiers.  If <key-
      id-length> equals to 0x00.  The value
      0x00 0x00, the <key-id> field is reserved for not contained in
      the TLV, and a pre-installed, shared key.

   <signature-data> key is used.

   <ICV-data>  is an unsigned integer field, whose length is <length> - 3,
      3 - <key-id-length>, and which contains the cryptographic signature. ICV.

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

      signature-value

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

   The hash function and the cryptographic function correspond to the
   entries in two IANA registries, set up by this specification 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 TLV type extension - is that adding
   further hash functions or cryptographic functions in the future may
   lead to a non-contiguous number space.

   The rationale for not including a field that lists parameters of the
   cryptographic signature ICV in the TLV is that, before being able to validate a
   cryptographic signature, ICV, routers have to exchange or acquire keys (e.g.
   public keys).  Any 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.  One implicitly available parameter
   is the length of the signature, ICV, which is <length> - 3, 3 - <key-id-length>,
   and which depends on the choice of the cryptographic function.

12.2.  Considerations for Calculating the Signature ICV

   In the following, considerations are listed, which MUST be applied
   when calculating the signature ICV for Packet, Message and Address
   SIGNATURE ICV TLVs,
   respectively.

12.2.1.  Packet SIGNATURE ICV TLV

   When determining the <signature-value> <ICV-value> for a Packet, the signature ICV is calculated
   over the three fields <hash-function>, <cryptographic-
   function> <cryptographic-function> <key-id-
   length>, and <key-index> - if present - <key-id> (in that order), concatenated
   with the entire Packet, including the packet header, all Packet TLVs
   (other than Packet SIGNATURE ICV TLVs) and all included Messages and their
   message headers, in accordance with Section 8.1.

12.2.2.  Message SIGNATURE ICV TLV

   When determining the <signature-value> <ICV-value> for a message, the signature ICV is calculated
   over the three fields <hash-function>, <cryptographic-
   function>, <cryptographic-function> <key-id-
   length>, and <key-index> - if present - <key-id> (in that order), concatenated
   with the entire message.  The considerations in Section 9.1 MUST be
   applied.

12.2.3.  Address Block SIGNATURE ICV TLV

   When determining the <signature-value> <ICV-value> for an address, the signature ICV is
   calculated over the three fields <hash-function>, <cryptographic-
   function>, <cryptographic-function>
   <key-id-length>, and <key-index> - if present - <key-id> (in that order),
   concatenated with the address, concatenated with any other values,
   for example, any other address block TLV <value> that is associated
   with that address.  A MANET routing protocol or MANET routing
   protocol extension using Address Block SIGNATURE ICV TLVs MUST specify how to
   include any such concatenated attribute of the address in the
   verification process of the signature. ICV.  The considerations in Section 10.2
   MUST be applied.

12.3.  Example of a Signed Message including an ICV

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

      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 = 40 44      | Msg. Orig Addr|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |       Message Originator Address (cont)       |   Hop Limit   |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   Hop Count   |    Message Sequence Number    | Msg. TLV Block|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | Length = 30 27   |   SIGNATURE     ICV       |  MTLVF = 144  |  MTLVExt = 1  |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |Value Len = 19 23 |   Hash Func   |  Crypto Func  |Key ID length=4|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                          Key Index Identifier                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                    Signature                          ICV Value                            |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                    Signature                          ICV Value (cont)                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                    Signature                          ICV Value (cont)                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                    Signature                          ICV Value (cont)                     |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 1: Example message with signature ICV

13.  IANA Considerations

   This specification defines:

   o  Two Packet TLV types, which must be allocated from the 0-223 range
      of the "Assigned Packet TLV Types" repository of [RFC5444] as
      specified in Table 1,

   o  Two Message TLV types, which must be allocated from the 0-127
      range of the "Assigned Message TLV Types" repository of [RFC5444]
      as specified in Table 2,

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

   This specification requests:

   o  Creation of type extension registries for these TLV types with
      initial values as in Table 1 to Table 3.

   IANA is requested to assign the same numerical value to the Packet
   TLV, Message TLV and Address Block TLV types with the same name.

   The following terms are used with the meanings defined in [BCP26]:
   "Namespace", "Assigned Value", "Registration", "Unassigned",
   "Reserved", "Hierarchical Allocation", and "Designated Expert".

   The following policies are policy is used with the meanings defined in [BCP26]:
   "Private Use",
   "Expert Review", and "Standards Action". Review".

13.1.  Expert Review: Evaluation Guidelines

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

   For the Timestamp TLV, the same type extensions for all Packet,
   Message and Address Block TLVs SHOULD be numbered identically.

13.2.  Packet TLV Type Registrations

   IANA is requested to make allocations from the "Packet TLV Types"
   namespace of [RFC5444] for the Packet TLVs specified in Table 1.

   +-----------+------+-----------+------------------------------------+
   |    Name   | Type |    Type   |             Description            |
   |           |      | Extension |                                    |
   +-----------+------+-----------+------------------------------------+
   | SIGNATURE    ICV    | TBD1 |     0     |        Signature           ICV of a packet          |
   |           |      |     1     |     Signature, ICV, decomposed into cryptographic |
   |           |      |           | cryptographic   function over a hash value, as   |
   |           |      |           |  value, as   specified in Section 12 in this  |
   |           |      |           |          in this              document.             |
   |           |      |   2-251   |            Expert Review           |
   |           |      |  252-255  |          Experimental Use          |
   | TIMESTAMP | TBD2 |     0     |   Unsigned timestamp of arbitrary  |
   |           |      |           |   length, given by the TLV length  |
   |           |      |           |  field. The MANET routing protocol |
   |           |      |           |   has to define how to interpret   |
   |           |      |           |           this timestamp           |
   |           |      |   1-251     1     |    Unsigned 32-bit timestamp as    |
   |           |      |           |        specified in [POSIX]        |
   |           |      |     2     | NTP timestamp format as defined in |
   |           |      |           |              [RFC4330]             |
   |           |      |     3     |    Signed timestamp of arbitrary   |
   |           |      |           | length with no constraints such as |
   |           |      |           |   monotonicity. In particular, it  |
   |           |      |           |   may represent any random value   |
   |           |      |   4-251   |            Expert Review           |
   |           |      |  252-255  |          Experimental Use          |
   +-----------+------+-----------+------------------------------------+

                         Table 1: Packet TLV types

13.3.  Message TLV Type Registrations

   IANA is requested to make allocations from the "Message TLV Types"
   namespace of [RFC5444] for the Message TLVs specified in Table 2.

   +-----------+------+-----------+------------------------------------+
   |    Name   | Type |    Type   |             Description            |
   |           |      | Extension |                                    |
   +-----------+------+-----------+------------------------------------+
   | SIGNATURE    ICV    | TBD3 |     0     |       Signature          ICV of a message          |
   |           |      |     1     |     Signature, ICV, decomposed into cryptographic |
   |           |      |           | cryptographic   function over a hash value, as   |
   |           |      |           |  value, as   specified in Section 12 in this  |
   |           |      |           |          in this              document.             |
   |           |      |   2-251   |            Expert Review           |
   |           |      |  252-255  |          Experimental Use          |
   | TIMESTAMP | TBD4 |     0     |   Unsigned timestamp of arbitrary  |
   |           |      |           |   length, given by the TLV length  |
   |           |      |           |               field.               |
   |           |      |   1-251     1     |    Unsigned 32-bit timestamp as    |
   |           |      |           |        specified in [POSIX]        |
   |           |      |     2     | NTP timestamp format as defined in |
   |           |      |           |              [RFC4330]             |
   |           |      |     3     |    Signed timestamp of arbitrary   |
   |           |      |           | length with no constraints such as |
   |           |      |           |   monotonicity. In particular, it  |
   |           |      |           |   may represent any random value   |
   |           |      |   4-251   |            Expert Review           |
   |           |      |  252-255  |          Experimental Use          |
   +-----------+------+-----------+------------------------------------+

                        Table 2: Message TLV types

13.4.  Address Block TLV Type Registrations

   IANA is requested to make allocations from the "Address Block TLV
   Types" namespace of [RFC5444] for the Packet TLVs specified in
   Table 3.

   +-----------+------+-----------+------------------------------------+
   |    Name   | Type |    Type   |             Description            |
   |           |      | Extension |                                    |
   +-----------+------+-----------+------------------------------------+
   | SIGNATURE    ICV    | TBD5 |     0     |   Signature ICV of an object (e.g. an  |
   |           |      |           | address) |
   |           |      |     1     |     Signature, ICV, decomposed into cryptographic |
   |           |      |           | cryptographic   function over a hash value, as   |
   |           |      |           |  value, as   specified in Section 12 in this  |
   |           |      |           |          in this              document.             |
   |           |      |   2-251   |            Expert Review           |
   |           |      |  252-255  |          Experimental Use          |
   | TIMESTAMP | TBD6 |     0     |   Unsigned timestamp of arbitrary  |
   |           |      |           |   length, given by the TLV length  |
   |           |      |           |               field.               |
   |           |      |   1-251     1     |    Unsigned 32-bit timestamp as    |
   |           |      |           |        specified in [POSIX]        |
   |           |      |     2     | NTP timestamp format as defined in |
   |           |      |           |              [RFC4330]             |
   |           |      |     3     |    Signed timestamp of arbitrary   |
   |           |      |           | length with no constraints such as |
   |           |      |           |   monotonicity. In particular, it  |
   |           |      |           |   may represent any random value   |
   |           |      |   4-251   |            Expert Review           |
   |           |      |  252-255  |          Experimental Use          |
   +-----------+------+-----------+------------------------------------+

                     Table 3: Address Block TLV types

13.5.  Hash Function

   IANA is requested to create a new registry for hash functions that
   can be used when creating a signature, an ICV, as specified in Section 12 of this
   document.  The initial assignments and allocation policies are
   specified in Table 4.

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

                      Table 4: Hash-Function registry

13.6.  Cryptographic Algorithm

   IANA is requested to create a new registry for the cryptographic
   function, as specified in Section 12 of this document.  Initial
   assignments and allocation policies are specified in Table 5.

   +----------------+-----------+--------------------------------------+
   |  Cryptographic | Algorithm |              Description             |
   | function value |           |                                      |
   +----------------+-----------+--------------------------------------+
   |        0       |    none   |  The "identity function": the value  |
   |                |           |   of an encrypted hash is the hash   |
   |                |           |                itself                |
   |      1-251        1       |    RSA    |               [RFC3447]              |
   |        2       |    DSA    |                 [DSA]                |
   |        3       |    HMAC   |               [RFC2104]              |
   |        4       |    3DES   |                [3DES]                |
   |        5       |    AES    |                 [AES]                |
   |        6       |   ECDSA   |                [ECDSA]               |
   |      7-251     |           |             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 signatures 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 the usage as well
   as the security that is attained by the cryptographic signatures ICVs of a
   message or a packet.

   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 signature, ICV, SHOULD indicate the security assumption
   that if the signature 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),
   Justin Dean (NRL), Christopher Dearlove (BAE), Paul Lambert
   (Marvell), Jerome Milan (Ecole Polytechnique) and Henning Rogge
   (FGAN) for their constructive comments on the document.

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

16.  References

16.1.  Normative References

   [3DES]     National Institute of Standards and Technology,
              "Recommendation for the Triple Data Encryption Algorithm
              (TDEA) Block Cipher", NIST Special Publication 800-67,
              May 2004.

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

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

   [DSA]      National Institute of Standards & Technology, "Digital ICV
              Standard", NIST, FIPS PUB 186, May 1994.

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

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

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

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

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

   [RFC4330]  Mills, D., "Simple Network Time Protocol (SNTP) Version 4
              for IPv4, IPv6 and OSI", RFC 4330, January 2006.

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

   [SHS]      National Institute of Standards and Technology, "Secure
              Hash Standard", NIST FIPS 180-2, August 2002.

16.2.  Informative References

   [OLSRv2]   Clausen, T., Dearlove, C., and P. Jacquet, "The Optimized
              Link State Routing Protocol version 2", work in
              progress draft-ietf-manet-olsrv2-13.txt, October 2011.

   [RFC6130]  Clausen, T., Dean, J., and C. Dearlove, "MANET
              Neighborhood Discovery Protocol (NHDP)", RFC 6130,
              March 2011.

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/