CBOR Object Signing and Encryption (COSE) Key Thumbprint
draft-ietf-cose-key-thumbprint-06

COSE                                                            K. Isobe
Internet-Draft                                           SECOM CO., LTD.
Intended status: Standards Track                           H. Tschofenig
Expires: 10 March 2025                                             H-BRS
                                                               O. Steele
                                                               Transmute
                                                        6 September 2024

        CBOR Object Signing and Encryption (COSE) Key Thumbprint
                   draft-ietf-cose-key-thumbprint-06

Abstract

   This specification defines a method for computing a hash value over a
   CBOR Object Signing and Encryption (COSE) Key. It specifies which
   fields within the COSE Key structure are included in the
   cryptographic hash computation, the process for creating a canonical
   representation of these fields, and how to hash the resulting byte
   sequence.  The resulting hash value, referred to as a "thumbprint,"
   can be used to identify or select the corresponding key.

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 https://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 10 March 2025.

Copyright Notice

   Copyright (c) 2024 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 (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights

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   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  COSE Key Thumbprint . . . . . . . . . . . . . . . . . . . . .   3
   4.  Required COSE Key Parameters  . . . . . . . . . . . . . . . .   3
     4.1.  Octet Key Pair (OKP)  . . . . . . . . . . . . . . . . . .   4
     4.2.  Elliptic Curve Keys with X- and Y-Coordinate Pair . . . .   4
     4.3.  RSA Public Keys . . . . . . . . . . . . . . . . . . . . .   4
     4.4.  Symmetric Keys  . . . . . . . . . . . . . . . . . . . . .   5
     4.5.  HSS-LMS . . . . . . . . . . . . . . . . . . . . . . . . .   5
     4.6.  Others  . . . . . . . . . . . . . . . . . . . . . . . . .   5
   5.  Miscellaneous Considerations  . . . . . . . . . . . . . . . .   5
     5.1.  Why Not Include Optional COSE Key Parameters? . . . . . .   5
     5.2.  Selection of Hash Function  . . . . . . . . . . . . . . .   6
     5.3.  Thumbprints of Keys Not in COSE Key Format  . . . . . . .   6
     5.4.  Relationship to Digests of X.509 Values . . . . . . . . .   6
     5.5.  Confirmation Method . . . . . . . . . . . . . . . . . . .   7
     5.6.  COSE Key Thumbprint URIs  . . . . . . . . . . . . . . . .   7
   6.  Example . . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  10
   9.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  11
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  11
     10.1.  Normative References . . . . . . . . . . . . . . . . . .  11
     10.2.  Informative References . . . . . . . . . . . . . . . . .  12
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  13

1.  Introduction

   This specification defines a method for applying a cryptographic hash
   function to a CBOR Object Signing and Encryption (COSE) Key structure
   [RFC9052], resulting in a hash value known as a "thumbprint."  To
   achieve this, the document specifies which fields in the COSE Key
   structure are included in the hash computation, the process for
   creating a canonical form of these fields, and how to hash the
   resulting byte sequence.  One of the primary use cases for this
   thumbprint is as a naming scheme for identifying or selecting the
   key, such as by using the COSE Key Thumbprint value as a "kid" (key
   ID).  Another key use case involves key derivation functions that use
   the thumbprints of public keys from the endpoints, along with other
   context, to derive a symmetric key.

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   This specification outlines how thumbprints of COSE Keys are
   generated for both asymmetric and symmetric keys (see Section 3 and
   Section 4).  Additionally, it introduces a new CBOR Web Token (CWT)
   confirmation method, which is added to the IANA "CWT Confirmation
   Methods" registry established by [RFC8747].  For further details on
   the use of a confirmation claim in a CWT with a proof-of-possession
   key, refer to Section 3.1 of [RFC8747].

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 BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.  COSE Key Thumbprint

   The thumbprint of a COSE Key MUST be computed as follows:

   1.  Construct a COSE_Key structure (see Section 7 of [RFC9052])
       containing only the required parameters representing the key as
       described in Section 4 of this document.

   2.  Apply the deterministic encoding described in Section 4.2.1 of
       [RFC8949] to the representation constructed in step (1).

   3.  Hash the bytes produced in step (2) with a cryptographic hash
       function H.  For example, SHA-256 [RFC6234] may be used as a hash
       function.

   The details of this computation are further described in subsequent
   sections.

   The SHA-256 hash algorithm MUST be supported, other algorithms MAY be
   supported.

4.  Required COSE Key Parameters

   Only the required parameters of a key's representation are used when
   computing its COSE Key Thumbprint value.  This section summarizes the
   required parameters.

   The "kty" (label: 1) element MUST be present for all key types, and
   the integer value specified in the IANA COSE Key Types registry MUST
   be used.  The tstr data type is not used with the kty element.

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   Many COSE Key parameters are specific to the chosen key type.  The
   following subsections list the required parameters for commonly used
   key types.

4.1.  Octet Key Pair (OKP)

   The required parameters for elliptic curve public keys that use the
   OKP key type, such as X25519, are:

   *  "kty" (label: 1, data type: int, value: 1)

   *  "crv" (label: -1, value: int)

   *  "x" (label: -2, value: bstr)

   Details can be found in Section 7.1 of [RFC9053].

4.2.  Elliptic Curve Keys with X- and Y-Coordinate Pair

   The required parameters for elliptic curve public keys that use the
   EC2 key type, such as NIST P-256, are:

   *  "kty" (label: 1, data type: int, value: 2)

   *  "crv" (label: -1, data type: int)

   *  "x" (label: -2, data type: bstr)

   *  "y" (label: -3, data type: bstr)

   Details can be found in Section 7.1 of [RFC9053].

   Note: [RFC9052] supports both compressed and uncompressed point
   representations.  For interoperability, implementations adhering to
   this specification MUST use the uncompressed point representation.
   Therefore, the y-coordinate is expressed as a bstr.  If an
   implementation uses the compressed point representation, it MUST
   first convert it to the uncompressed form for the purpose of
   thumbprint calculation.

4.3.  RSA Public Keys

   The required parameters for an RSA public key are:

   *  "kty" (label: 1, data type: int, value: 3)

   *  "n" (label: -1, data type: bstr)

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   *  "e" (label: -2, data type: bstr)

4.4.  Symmetric Keys

   The required parameters for a symmetric key are:

   *  "kty" (label: 1, data type: int, value: 4)

   *  "k" (label: -1, data type: bstr)

4.5.  HSS-LMS

   The required parameters for HSS-LMS keys are:

   *  "kty" (label: 1, data type: int, value: 5)

   *  "pub" (label: -1, data type: bstr)

4.6.  Others

   As other key type values are defined, the specifications defining
   them should be similarly consulted to determine which parameters, in
   addition to the "kty" element, are required.

5.  Miscellaneous Considerations

5.1.  Why Not Include Optional COSE Key Parameters?

   Optional parameters of COSE Keys are intentionally not included in
   the COSE Key Thumbprint computation so that their absence or presence
   in the COSE Key does not alter the resulting value.  The COSE Key
   Thumbprint is a digest of the essential parameters required to
   represent the key as a COSE Key, rather than any additional data that
   might accompany the key.

   By excluding optional parameters, the COSE Key Thumbprint
   consistently refers to the key itself, not to a key with additional
   attributes.  Different application contexts may include various
   optional attributes in the COSE Key structure.  If these optional
   parameters were included in the thumbprint calculation, the resulting
   values could differ for the same key depending on the attributes
   present.  Including only the required parameters ensures that the
   COSE Key Thumbprint remains consistent for a given key, regardless of
   any additional attributes.

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   Different kinds of thumbprints could be defined by other
   specifications that might include some or all additional COSE Key
   parameters, if use cases arise where such different kinds of
   thumbprints would be useful.

5.2.  Selection of Hash Function

   A specific hash function must be chosen by an application to compute
   the hash value of the hash input.  For instance, SHA-256 [RFC6234]
   may be used as the hash function.  While SHA-256 is a good default
   choice at the time of writing, the preferred hash function may evolve
   as the cryptographic landscape develops.

   In many cases, only the party that generates the key needs to be
   aware of the hash function used.  For example, the key producer might
   use the thumbprint value as a "kid" (key ID).  In such scenarios, the
   consumer of the "kid" treats it as an opaque value solely for key
   selection.

   However, when multiple parties are involved in reproducing and
   comparing the COSE Key Thumbprint, it is crucial that they know and
   use the same hash function to ensure consistent results.

5.3.  Thumbprints of Keys Not in COSE Key Format

   Keys that are in other formats can be represented as COSE Keys.  Any
   party in possession of a key that is represented as a COSE Key can
   use the COSE Key Thumbprint.

5.4.  Relationship to Digests of X.509 Values

   COSE Key Thumbprint values are computed on the COSE Key object
   required to represent a key, rather than all parameters of a COSE Key
   that the key is represented in.  Thus, they are more analogous to
   applications that use digests of X.509 Subject Public Key Info (SPKI)
   values, which are defined in Section 4.1.2.7 of [RFC5280], than to
   applications that use digests of complete certificate values, as the
   "x5t" (X.509 certificate SHA-1 thumbprint) [RFC9360] value defined
   for X.509 certificate objects does.  While logically equivalent to a
   digest of the SPKI representation of the key, a COSE Key Thumbprint
   is computed over the CBOR representation of that key, rather than
   over an ASN.1 representation of it.

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5.5.  Confirmation Method

   [RFC8747] introduced confirmation methods for use with CBOR Web
   Tokens (CWTs) with the addition of the "cnf" claim.  CWTs have been
   defined in [RFC8392].  This specification adds a new confirmation
   method based on COSE Key Thumbprints.

   The proof-of-possession key is identified using the "ckt" claim, the
   COSE Key Thumbprint claim.  This claim contains the value of the COSE
   Key Thumbprint encoded as a binary string.  Instead of communicating
   the actual COSE Key only the thumbprint is conveyed.  This approach
   assumes that the recipient is able to obtain the identified COSE Key
   using the thumbprint contained in the "ckt" claim.  In this approach,
   the issuer of a CWT declares that the presenter possesses a
   particular key and that the recipient can cryptographically confirm
   the presenter's proof of possession of the key by including a "ckt"
   claim in the CWT.

   The following example demonstrates the use of the "ckt" claim in a
   CWT as part of the confirmation method (with line-breaks inserted for
   editorial reasons):

      {
       /iss/ 1 : "coaps://as.example.com",
       /aud/ 3 : "coaps://resource.example.org",
       /exp/ 4 : 1361398824,
       /cnf/ 8 : {
         /ckt/ [[TBD1]] : h'496bd8afadf307e5b08c64b0421bf9dc
                     01528a344a43bda88fadd1669da253ec'
        }
      }

   Section 8 registers the "ckt" claim and the confirmation method.  The
   "ckt" claim is expected to be used in the "cnf" claim.

5.6.  COSE Key Thumbprint URIs

   This specification defines Uniform Resource Identifiers (URIs) to
   represent a COSE Key Thumbprint value.  The design follows the work
   of the JSON Web Key (JWK) Thumbprint URIs, specified in [RFC9278].
   This enables COSE Key Thumbprints to be used, for example, as key
   identifiers in contexts requiring URIs.  This specification defines a
   URI prefix indicating that the portion of the URI following the
   prefix is a COSE Key Thumbprint.

   The following URI prefix is defined to indicate that the portion of
   the URI following the prefix is a COSE Key Thumbprint:

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     urn:ietf:params:oauth:ckt

   To make the hash algorithm being used explicit in a URI, the prefix
   is followed by a hash algorithm identifier and a COSE Key Thumbprint
   value, each separated by a colon character to form a URI representing
   a COSE Key Thumbprint.

   Hash algorithm identifiers used in COSE Key Thumbprint URIs MUST be
   values from the "Hash Name String" column in the IANA "Named
   Information Hash Algorithm Registry" [IANA.Hash.Algorithms].  COSE
   Key Thumbprint URIs with hash algorithm identifiers not found in this
   registry are not considered valid and applications MUST detect and
   handle this error, should it occur.

   Since the URN is encoded as a string, the output of the COSE Key
   Thumbprint computation described in Section 3 MUST be base64url
   encoded without padding.

   [RFC7515] specifies Base64url encoding as follows:

   "Base64 encoding using the URL- and filename-safe character set
   defined in Section 5 of RFC 4648 [RFC4648], with all trailing '='
   characters omitted and without the inclusion of any line breaks,
   whitespace, or other additional characters.  Note that the base64url
   encoding of the empty octet sequence is the empty string.  (See
   Appendix C of [RFC7515] for notes on implementing base64url encoding
   without padding.)"

   The base64url encoding of the thumbprint shown in Section 6 is shown
   below (with a line-break added for readability purposes).

   SWvYr63zB-WwjGSwQhv53AFSijRKQ72oj63RZp2iU-w

   The full example of a COSE Key Thumbprint URI is shown below, again
   with a line-break added.

   urn:ietf:params:oauth:ckt:sha-256:
   SWvYr63zB-WwjGSwQhv53AFSijRKQ72oj63RZp2iU-w

6.  Example

   This section demonstrates the COSE Key Thumbprint computation for the
   following example COSE Key containing an ECC public key.

   For better readability, the example is first presented in CBOR
   diagnostic format (with the long line broken for display purposes
   only).

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     {
       / kty set to EC2 = Elliptic Curve Keys /
       1:2,
       / crv set to P-256 /
       -1:1,
       / public key: x-coordinate /
       -2:h'65eda5a12577c2bae829437fe338701a10aaa375e1bb5b5de108de439c0
   8551d',
       / public key: y-coordinate /
       -3:h'1e52ed75701163f7f9e40ddf9f341b3dc9ba860af7e0ca7ca7e9eecd008
   4d19c',
       / kid is bstr, not used in COSE Key Thumbprint /
       2:h'1decade2facade3'
     }

   The example above corresponds to the following CBOR encoding (with
   link breaks added for display purposes only):

   A50102200121582065EDA5A12577C2BAE829437FE338701A10AAA375E1BB5B5DE108D
   E439C08551D2258201E52ED75701163F7F9E40DDF9F341B3DC9BA860AF7E0CA7CA7E9
   EECD0084D19C0258246D65726961646F632E6272616E64796275636B406275636B6C6
   16E642E6578616D706C65

   Not all of the parameters from the example above are used in the COSE
   Key Thumbprint computation since the required parameters of an
   elliptic curve public key are (as listed in Section 4.2) "kty",
   "crv", "x", and "y".

   The resulting COSE Key structure, in CBOR diagnostic format with
   line-breaks added for better readability, with the minimum parameters
   in the correct order are.

   {
      1:2,
     -1:1,
     -2:h'65eda5a12577c2bae829437fe338701a
          10aaa375e1bb5b5de108de439c08551d',
     -3:h'1e52ed75701163f7f9e40ddf9f341b3d
          c9ba860af7e0ca7ca7e9eecd0084d19c'
   }

   In CBOR encoding the result is (with line-breaks added for display
   purposes only):

   A40102200121582065EDA5A12577C2BAE829437FE338701A10AAA375E1BB5B5DE
   108DE439C08551D2258201E52ED75701163F7F9E40DDF9F341B3DC9BA860AF7E0
   CA7CA7E9EECD0084D19C

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   Using SHA-256, the resulting thumbprint is:

   496bd8afadf307e5b08c64b0421bf9dc01528a344a43bda88fadd1669da253ec

7.  Security Considerations

   A COSE Key Thumbprint will only uniquely identify a particular key if
   a single unambiguous COSE Key representation for that key is defined
   and used when computing the COSE Key Thumbprint.

   A COSE Key Thumbprint will only uniquely identify a particular key if
   a single unambiguous COSE Key representation for that key is defined
   and used when computing the COSE Key Thumbprint.  Key identifiers are
   not included in the thumbprint calculation (similarly to other
   optional parameters in the COSE_Key structure).  If the inclusion of
   specific optional parameters in the thumbprint calculation is
   important for a particular application, this specification would not
   be suitable.

   While thumbprint values are useful for identifying legitimate keys,
   comparing thumbprint values is not a reliable means of excluding the
   use of particular keys (or transformations thereof).  The reason is
   that an attacker may supply a key that is a transformation of a key
   in order to have it appear to be a different key.  For instance, if a
   legitimate RSA key uses a modulus value N and an attacker supplies a
   key with modulus 3*N, the modified key would still work about 1/3 of
   the time, but would appear to be a different key.

   Producing thumbprints of symmetric keys needs to be done with care.
   Developers MUST ensure that the symmetric key has sufficient entropy
   to prevent attackers to precompute tables of symmetric keys with
   their corresponding hash values.  This can be prevented if the
   symmetric key is a randomly selected key of at least 128 bit length.
   Thumbprints MUST NOT be used with passwords or other low-entropy
   secrets.  If a developer is unable to determine whether all symmetric
   keys used in an application have sufficient entropy, then thumbprints
   of symmetric keys MUST NOT be used.  In general, using thumbprints of
   symmetric keys should only be used in special applications.  In most
   other deployment scenarios it is more appropriate to utilize a
   different naming scheme for key identifiers.

8.  IANA Considerations

   IANA is requested to add the following entry to the IANA "CWT
   Confirmation Methods" registry established by [RFC8747]:

   *  Confirmation Method Name: ckt

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   *  Confirmation Method Description: COSE Key SHA-256 Thumbprint

   *  JWT Confirmation Method Name: jkt

   *  Confirmation Key: [[TBD1]]

   *  Confirmation Value Type(s): binary string

   *  Change Controller: IETF

   *  Specification Document(s): [[This document]]

   Furthermore, IANA is requested to add a value to the IANA "OAuth URI"
   registry established with [RFC6755]:

   *  URN: urn:ietf:params:oauth:ckt

   *  Common Name: COSE Key Thumbprint URI

   *  Change controller: IETF

   *  Specification Document: [[This document]]

9.  Acknowledgements

   We would like to thank the authors of [RFC7638] for their work on the
   JSON Web Key (JWK) Thumbprint specification.  This document applies
   JWK Thumbprints to COSE Key structures.

   Additionally, we would like to thank Carsten Bormann, Ilari
   Liusvaara, Laurence Lundblade, Daisuke Ajitomi, Michael Richardson,
   Michael B.  Jones, Mallory Knodel, Joel Jaeggli, Derrell Piper,
   Patrik Fältström, Warren Kumari, Deb Cooley and Brendan Moran for
   their feedback.

10.  References

10.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/rfc/rfc2119>.

   [RFC4648]  Josefsson, S., "The Base16, Base32, and Base64 Data
              Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
              <https://www.rfc-editor.org/rfc/rfc4648>.

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   [RFC6755]  Campbell, B. and H. Tschofenig, "An IETF URN Sub-Namespace
              for OAuth", RFC 6755, DOI 10.17487/RFC6755, October 2012,
              <https://www.rfc-editor.org/rfc/rfc6755>.

   [RFC7515]  Jones, M., Bradley, J., and N. Sakimura, "JSON Web
              Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
              2015, <https://www.rfc-editor.org/rfc/rfc7515>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/rfc/rfc8174>.

   [RFC8392]  Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig,
              "CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392,
              May 2018, <https://www.rfc-editor.org/rfc/rfc8392>.

   [RFC8747]  Jones, M., Seitz, L., Selander, G., Erdtman, S., and H.
              Tschofenig, "Proof-of-Possession Key Semantics for CBOR
              Web Tokens (CWTs)", RFC 8747, DOI 10.17487/RFC8747, March
              2020, <https://www.rfc-editor.org/rfc/rfc8747>.

   [RFC8949]  Bormann, C. and P. Hoffman, "Concise Binary Object
              Representation (CBOR)", STD 94, RFC 8949,
              DOI 10.17487/RFC8949, December 2020,
              <https://www.rfc-editor.org/rfc/rfc8949>.

   [RFC9052]  Schaad, J., "CBOR Object Signing and Encryption (COSE):
              Structures and Process", STD 96, RFC 9052,
              DOI 10.17487/RFC9052, August 2022,
              <https://www.rfc-editor.org/rfc/rfc9052>.

   [RFC9053]  Schaad, J., "CBOR Object Signing and Encryption (COSE):
              Initial Algorithms", RFC 9053, DOI 10.17487/RFC9053,
              August 2022, <https://www.rfc-editor.org/rfc/rfc9053>.

10.2.  Informative References

   [IANA.Hash.Algorithms]
              "Named Information Hash Algorithm Registry",
              <https://www.iana.org/assignments/named-information>.

   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
              <https://www.rfc-editor.org/rfc/rfc5280>.

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   [RFC6234]  Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms
              (SHA and SHA-based HMAC and HKDF)", RFC 6234,
              DOI 10.17487/RFC6234, May 2011,
              <https://www.rfc-editor.org/rfc/rfc6234>.

   [RFC7638]  Jones, M. and N. Sakimura, "JSON Web Key (JWK)
              Thumbprint", RFC 7638, DOI 10.17487/RFC7638, September
              2015, <https://www.rfc-editor.org/rfc/rfc7638>.

   [RFC9278]  Jones, M. and K. Yasuda, "JWK Thumbprint URI", RFC 9278,
              DOI 10.17487/RFC9278, August 2022,
              <https://www.rfc-editor.org/rfc/rfc9278>.

   [RFC9360]  Schaad, J., "CBOR Object Signing and Encryption (COSE):
              Header Parameters for Carrying and Referencing X.509
              Certificates", RFC 9360, DOI 10.17487/RFC9360, February
              2023, <https://www.rfc-editor.org/rfc/rfc9360>.

Authors' Addresses

   Kohei Isobe
   SECOM CO., LTD.
   Email: isobekohei@gmail.com

   Hannes Tschofenig
   University of Applied Sciences Bonn-Rhein-Sieg
   Germany
   Email: hannes.tschofenig@gmx.net

   Orie Steele
   Transmute
   United States
   Email: orie@transmute.industries

Isobe, et al.             Expires 10 March 2025                [Page 13]