SACM Working Group                                           H. Birkholz
Internet-Draft                                            Fraunhofer SIT
Intended status: Standards Track                     J. Fitzgerald-McKay
Expires: 26 August 2021                         National Security Agency
                                                              C. Schmidt
                                                   The MITRE Corporation
                                                           D. Waltermire
                                                                    NIST
                                                        22 February 2021


                  Concise Software Identification Tags
                       draft-ietf-sacm-coswid-17

Abstract

   ISO/IEC 19770-2:2015 Software Identification (SWID) tags provide an
   extensible XML-based structure to identify and describe individual
   software components, patches, and installation bundles.  SWID tag
   representations can be too large for devices with network and storage
   constraints.  This document defines a concise representation of SWID
   tags: Concise SWID (CoSWID) tags.  CoSWID supports a similar set of
   semantics and features as SWID tags, as well as new semantics that
   allow CoSWIDs to describe additional types of information, all in a
   more memory efficient format.

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 26 August 2021.

Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




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   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
   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.  The SWID and CoSWID Tag Lifecycle . . . . . . . . . . . .   5
     1.2.  Concise SWID Format . . . . . . . . . . . . . . . . . . .   8
     1.3.  Requirements Notation . . . . . . . . . . . . . . . . . .   8
   2.  Concise SWID Data Definition  . . . . . . . . . . . . . . . .   8
     2.1.  Character Encoding  . . . . . . . . . . . . . . . . . . .  10
     2.2.  Concise SWID Extensions . . . . . . . . . . . . . . . . .  10
     2.3.  The concise-swid-tag Map  . . . . . . . . . . . . . . . .  12
     2.4.  concise-swid-tag Co-Constraints . . . . . . . . . . . . .  16
     2.5.  The global-attributes Group . . . . . . . . . . . . . . .  17
     2.6.  The entity-entry Map  . . . . . . . . . . . . . . . . . .  18
     2.7.  The link-entry Map  . . . . . . . . . . . . . . . . . . .  19
     2.8.  The software-meta-entry Map . . . . . . . . . . . . . . .  23
     2.9.  The Resource Collection Definition  . . . . . . . . . . .  27
       2.9.1.  The hash-entry Array  . . . . . . . . . . . . . . . .  27
       2.9.2.  The resource-collection Group . . . . . . . . . . . .  27
       2.9.3.  The payload-entry Map . . . . . . . . . . . . . . . .  31
       2.9.4.  The evidence-entry Map  . . . . . . . . . . . . . . .  31
     2.10. Full CDDL Specification . . . . . . . . . . . . . . . . .  32
   3.  Determining the Type of CoSWID  . . . . . . . . . . . . . . .  38
   4.  CoSWID Indexed Label Values . . . . . . . . . . . . . . . . .  38
     4.1.  Version Scheme  . . . . . . . . . . . . . . . . . . . . .  39
     4.2.  Entity Role Values  . . . . . . . . . . . . . . . . . . .  40
     4.3.  Link Ownership Values . . . . . . . . . . . . . . . . . .  42
     4.4.  Link Rel Values . . . . . . . . . . . . . . . . . . . . .  43
     4.5.  Link Use Values . . . . . . . . . . . . . . . . . . . . .  45
   5.  URI Schemes . . . . . . . . . . . . . . . . . . . . . . . . .  45
     5.1.  "swid" URI Scheme Specification . . . . . . . . . . . . .  46
     5.2.  "swidpath" URI Scheme Specification . . . . . . . . . . .  46
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  46
     6.1.  CoSWID Items Registry . . . . . . . . . . . . . . . . . .  47
     6.2.  Software Tag Values Registries  . . . . . . . . . . . . .  50
       6.2.1.  Registration Procedures . . . . . . . . . . . . . . .  50
       6.2.2.  Private Use of Index and Name Values  . . . . . . . .  50
       6.2.3.  Expert Review Guidelines  . . . . . . . . . . . . . .  50
       6.2.4.  Software Tag Version Scheme Values Registry . . . . .  51
       6.2.5.  Software Tag Entity Role Values Registry  . . . . . .  53



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       6.2.6.  Software Tag Link Ownership Values Registry . . . . .  54
       6.2.7.  Software Tag Link Relationship Values Registry  . . .  55
       6.2.8.  Software Tag Link Use Values Registry . . . . . . . .  58
     6.3.  swid+cbor Media Type Registration . . . . . . . . . . . .  59
     6.4.  CoAP Content-Format Registration  . . . . . . . . . . . .  60
     6.5.  CBOR Tag Registration . . . . . . . . . . . . . . . . . .  60
     6.6.  URI Scheme Registrations  . . . . . . . . . . . . . . . .  61
       6.6.1.  "swid" URI Scheme Registration  . . . . . . . . . . .  61
       6.6.2.  "swidpath" URI Scheme Registration  . . . . . . . . .  61
     6.7.  CoSWID Model for use in SWIMA Registration  . . . . . . .  62
   7.  Signed CoSWID Tags  . . . . . . . . . . . . . . . . . . . . .  63
   8.  Tagged CoSWID Tags  . . . . . . . . . . . . . . . . . . . . .  64
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  65
   10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  67
   11. Change Log  . . . . . . . . . . . . . . . . . . . . . . . . .  67
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .  72
     12.1.  Normative References . . . . . . . . . . . . . . . . . .  72
     12.2.  Informative References . . . . . . . . . . . . . . . . .  75
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  76

1.  Introduction

   SWID tags, as defined in ISO-19770-2:2015 [SWID], provide a
   standardized XML-based record format that identifies and describes a
   specific release of software, a patch, or an installation bundle,
   which are referred to as software components in this document.
   Different software components, and even different releases of a
   particular software component, each have a different SWID tag record
   associated with them.  SWID tags are meant to be flexible and able to
   express a broad set of metadata about a software component.

   SWID tags are used to support a number of processes including but not
   limited to:

   *  Software Inventory Management, a part of a Software Asset
      Management [SAM] process, which requires an accurate list of
      discernible deployed software components.

   *  Vulnerability Assessment, which requires a semantic link between
      standardized vulnerability descriptions and software components
      installed on IT-assets [X.1520].

   *  Remote Attestation, which requires a link between reference
      integrity measurements (RIM) and Attester-produced event logs that
      complement attestation Evidence [I-D.ietf-rats-architecture].






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   While there are very few required fields in SWID tags, there are many
   optional fields that support different uses.  A SWID tag consisting
   of only required fields might be a few hundred bytes in size;
   however, a tag containing many of the optional fields can be many
   orders of magnitude larger.  Thus, real-world instances of SWID tags
   can be fairly large, and the communication of SWID tags in usage
   scenarios, such as those described earlier, can cause a large amount
   of data to be transported.  This can be larger than acceptable for
   constrained devices and networks.  Concise SWID (CoSWID) tags
   significantly reduce the amount of data transported as compared to a
   typical SWID tag through the use of the Concise Binary Object
   Representation (CBOR) [RFC7049].

   Size comparisons between XML SWID and CoSWID mainly depend on domain-
   specific applications and the complexity of attributes used in
   instances.  While the values stored in CoSWID are often unchanged and
   therefore not reduced in size compared to an XML SWID, the
   scaffolding that the CoSWID encoding represents is significantly
   smaller by taking up 10 percent or less in size.  This effect is
   visible in instances sizes, which can benefit from a 50 percent to 85
   percent reduction of size in generic usage scenarios.  Additional
   size reduction is enabled with respect to the memory footprint of XML
   parsing/validation as well as the reduction of stack sizes where XML
   processing is now obsolete.

   In a CoSWID, the human-readable labels of SWID data items are
   replaced with more concise integer labels (indices).  This approach
   allows SWID and CoSWID to share a common implicit information model,
   with CoSWID providing an alternate data model [RFC3444].  While SWID
   and CoSWID are intended to share the same implicit information model,
   this specification does not define this information model, or a
   mapping between the the two data formats.  While an attempt to align
   SWID and CoSWID tags has been made here, future revisions of ISO/IEC
   19770-2:2015 or this specification might cause this implicit
   information model to diverge, since these specifications are
   maintained by different standards groups.

   The use of CBOR to express SWID information in CoSWID tags allows
   both CoSWID and SWID tags to be part of an enterprise security
   solution for a wider range of endpoints and environments.











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1.1.  The SWID and CoSWID Tag Lifecycle

   In addition to defining the format of a SWID tag record, ISO/IEC
   19770-2:2015 defines requirements concerning the SWID tag lifecycle.
   Specifically, when a software component is installed on an endpoint,
   that software component's SWID tag is also installed.  Likewise, when
   the software component is uninstalled or replaced, the SWID tag is
   deleted or replaced, as appropriate.  As a result, ISO/IEC
   19770-2:2015 describes a system wherein there is a correspondence
   between the set of installed software components on an endpoint, and
   the presence of the corresponding SWID tags for these components on
   that endpoint.  CoSWIDs share the same lifecycle requirements as a
   SWID tag.

   The SWID specification and supporting guidance provided in NIST
   Internal Report (NISTIR) 8060: Guidelines for the Creation of
   Interoperable SWID Tags [SWID-GUIDANCE] defines four types of SWID
   tags: primary, patch, corpus, and supplemental.  The following text
   is paraphrased from these sources.

   1.  Primary Tag - A SWID or CoSWID tag that identifies and describes
       an installed software component on an endpoint.  A primary tag is
       intended to be installed on an endpoint along with the
       corresponding software component.

   2.  Patch Tag - A SWID or CoSWID tag that identifies and describes an
       installed patch that has made incremental changes to a software
       component installed on an endpoint.  A patch tag is intended to
       be installed on an endpoint along with the corresponding software
       component patch.

   3.  Corpus Tag - A SWID or CoSWID tag that identifies and describes
       an installable software component in its pre-installation state.
       A corpus tag can be used to represent metadata about an
       installation package or installer for a software component, a
       software update, or a patch.

   4.  Supplemental Tag - A SWID or CoSWID tag that allows additional
       information to be associated with a referenced SWID tag.  This
       allows tools and users to record their own metadata about a
       software component without modifying SWID primary or patch tags
       created by a software provider.

   The type of a tag is determined by specific data elements, which are
   discussed in Section 3, which also provides normative language for
   CoSWID semantics that implement this lifecycle.  The following
   information helps to explain how these semantics apply to use of a
   CoSWID tag.



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      Corpus, primary, and patch tags have similar functions in that
      they describe the existence and/or presence of different types of
      software components (e.g., software installers, software
      installations, software patches), and, potentially, different
      states of these software components.  Supplemental tags have the
      same structure as other tags, but are used to provide information
      not contained in the referenced corpus, primary, and patch tags.
      All four tag types come into play at various points in the
      software lifecycle and support software management processes that
      depend on the ability to accurately determine where each software
      component is in its lifecycle.

                                    +------------+
                                    v            |
  Software      Software        Software     Software      Software
  Deployment -> Installation -> Patching  -> Upgrading  -> Removal

  Corpus        Primary         Primary      xPrimary      xPrimary
  Supplemental  Supplemental    Supplemental xSupplemental xSupplemental
                                Patch        xPatch
                                             Primary
                                             Supplemental

           Figure 1: Use of Tag Types in the Software Lifecycle

      Figure 1 illustrates the steps in the software lifecycle and the
      relationships among those lifecycle events supported by the four
      types of SWID and CoSWID tags.  A detailed description of the four
      tags types is provided in Section 2.3.  The figure identifies the
      types of tags that are used in each lifecycle event.

   There are many ways in which software tags might be managed for the
   host the software is installed on.  For example, software tags could
   be made available on the host or to an external software manager when
   storage is limited on the host.

   In these cases the host or external software manager is responsible
   for management of the tags, including deployment and removal of the
   tags as indicated by the above lifecycle.  Tags are deployed and
   previously deployed tags that are typically removed (indicated by an
   "x" prefix) at each lifecycle stage, as follows:

      -  Software Deployment.  Before the software component is
         installed (i.e., pre-installation), and while the product is
         being deployed, a corpus tag provides information about the
         installation files and distribution media (e.g., CD/DVD,
         distribution package).




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   Corpus tags are not actually deployed on the target system but are
   intended to support deployment procedures and their dependencies at
   install-time, such as to verify the installation media.

      -  Software Installation.  A primary tag will be installed with
         the software component (or subsequently created) to uniquely
         identify and describe the software component.  Supplemental
         tags are created to augment primary tags with additional site-
         specific or extended information.  While not illustrated in the
         figure, patch tags can also be installed during software
         installation to provide information about software fixes
         deployed along with the base software installation.

      -  Software Patching.  A new patch tag is provided, when a patch
         is applied to the software component, supplying details about
         the patch and its dependencies.  While not illustrated in the
         figure, a corpus tag can also provide information about the
         patch installer and patching dependencies that need to be
         installed before the patch.

      -  Software Upgrading.  As a software component is upgraded to a
         new version, new primary and supplemental tags replace existing
         tags, enabling timely and accurate tracking of updates to
         software inventory.  While not illustrated in the figure, a
         corpus tag can also provide information about the upgrade
         installer and dependencies that need to be installed before the
         upgrade.

   Note: In the context of software tagging software patching and
   updating differ in an important way.  When installing a patch, a set
   of file modifications are made to pre-installed software which do not
   alter the version number or the descriptive metadata of an installed
   software component.  An update can also make a set of file
   modifications, but the version number or the descriptive metadata of
   an installed software component are changed.

      -  Software Removal.  Upon removal of the software component,
         relevant SWID tags are removed.  This removal event can trigger
         timely updates to software inventory reflecting the removal of
         the product and any associated patch or supplemental tags.

   As illustrated in the figure, supplemental tags can be associated
   with any corpus, primary, or patch tag to provide additional metadata
   about an installer, installed software, or installed patch
   respectively.






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   Understanding the use of CoSWIDs in the software lifecycle provides a
   basis for understanding the information provided in a CoSWID and the
   associated semantics of this information.  Each of the different SWID
   and CoSWID tag types provide different sets of information.  For
   example, a "corpus tag" is used to describe a software component's
   installation image on an installation media, while a "patch tag" is
   meant to describe a patch that modifies some other software
   component.

1.2.  Concise SWID Format

   This document defines the CoSWID tag format, which is based on CBOR.
   CBOR-based CoSWID tags offer a more concise representation of SWID
   information as compared to the XML-based SWID tag representation in
   ISO-19770-2:2015.  The structure of a CoSWID is described via the
   Concise Data Definition Language (CDDL) [RFC8610].  The resulting
   CoSWID data definition is aligned to the information able to be
   expressed with the XML schema definition of ISO-19770-2:2015 [SWID].
   This alignment allows both SWID and CoSWID tags to represent a common
   set of software component information and allows CoSWID tags to
   support the same uses as a SWID tag.

   The vocabulary, i.e., the CDDL names of the types and members used in
   the CoSWID CDDL specification, are mapped to more concise labels
   represented as small integer values (indices).  The names used in the
   CDDL specification and the mapping to the CBOR representation using
   integer indices is based on the vocabulary of the XML attribute and
   element names defined in ISO/IEC 19770-2:2015.

1.3.  Requirements Notation

   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.

2.  Concise SWID Data Definition

   The following describes the general rules and processes for encoding
   data using CDDL representation.  Prior familiarity with CBOR and CDDL
   concepts will be helpful in understanding this CoSWID specification.

   This section describes the conventions by which a CoSWID is
   represented in the CDDL structure.  The CamelCase [CamelCase]
   notation used in the XML schema definition is changed to a hyphen-
   separated notation [KebabCase] (e.g.  ResourceCollection is named
   resource-collection) in the CoSWID CDDL specification.  This



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   deviation from the original notation used in the XML representation
   reduces ambiguity when referencing certain attributes in
   corresponding textual descriptions.  An attribute referred to by its
   name in CamelCase notation explicitly relates to XML SWID tags; an
   attribute referred to by its name in KebabCase notation explicitly
   relates to CBOR CoSWID tags.  This approach simplifies the
   composition of further work that reference both XML SWID and CBOR
   CoSWID documents.

   In most cases, mapping attribute names between SWID and CoSWID can be
   done automatically by converting between CamelCase and KebabCase
   attribute names.  However, some CoSWID CDDL attribute names show
   greater variation relative to their corresponding SWID XML Schema
   attributes.  This is done when the change improves clarity in the
   CoSWID specification.  For example the "name" and "version" SWID
   fields corresponds to the "software-name" and "software-version"
   CoSWID fields, respectively.  As such, it is not always possible to
   mechanically translate between corresponding attribute names in the
   two formats.  In such cases, a manual mapping will need to be used.
   These cases are specifically noted in this and subsequent sections
   using an [W3C.REC-xpath20-20101214] where a manual mapping is needed.

   The 57 human-readable text labels of the CDDL-based CoSWID vocabulary
   are mapped to integer indices via a block of rules at the bottom of
   the definition.  This allows a more concise integer-based form to be
   stored or transported, as compared to the less efficient text-based
   form of the original vocabulary.

   The root of the CDDL specification provided by this document is the
   rule "coswid" (as defined in Section 8):

   start = coswid

   In CBOR, an array is encoded using bytes that identify the array, and
   the array's length or stop point (see [RFC7049]).  To make items that
   support 1 or more values, the following CDDL notation is used.

   _name_ = (_label_ => _data_ / [ 2* _data_ ])

   The CDDL rule above allows either a single data item or an array of 2
   or more data values to be provided.  When a singleton data value is
   provided, the CBOR markers for the array, array length, and stop
   point are not needed, saving bytes.  When two or more data values are
   provided, these values are encoded as an array.  This modeling
   pattern is used frequently in the CoSWID CDDL specification to allow
   for more efficient encoding of singleton values.

   Usage of this construct can be simplified using



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   one-or-more<T> = T / [ 2* T ]

   simplifying the above example to

   _name_ = (_label_ => one-or-more<_data_>)

   The following subsections describe the different parts of the CoSWID
   model.

2.1.  Character Encoding

   The CDDL "text" type is represented in CBOR as a major type 3, which
   represents "a string of Unicode characters that [are] encoded as
   UTF-8 [RFC3629]" (see [RFC7049] Section 2.1).  Thus both SWID and
   CoSWID use UTF-8 for the encoding of characters in text strings.

   To ensure that UTF-8 character strings are able to be encoded/decoded
   and exchanged interoperably, text strings in CoSWID MUST be encoded
   consistent with the Net-Unicode definition defined in [RFC5198].

   All names registered with IANA according to requirements in
   Section 6.2 also MUST be valid according to the XML Schema NMToken
   data type (see [W3C.REC-xmlschema-2-20041028] Section 3.3.4) to
   ensure compatibility with the SWID specification where these names
   are used.

2.2.  Concise SWID Extensions

   The CoSWID specification contains two features that are not included
   in the SWID specification on which it is based.  These features are:

   *  The explicit definition of types for some attributes in the ISO-
      19770-2:2015 XML representation that are typically represented by
      the "any attribute" in the SWID model.  These are covered in
      Section 2.5.

   *  The inclusion of extension points in the CoSWID specification
      using CDDL sockets (see [RFC8610] Section 3.9).  The use of CDDL
      sockets allow for well-formed extensions to be defined in
      supplementary CDDL descriptions that support additional uses of
      CoSWID tags that go beyond the original scope of ISO-19770-2:2015
      tags.  This extension mechanism can also be used to update the
      CoSWID format as revisions to ISO-19770-2 are published.

   The following CDDL sockets (extension points) are defined in this
   document, which allow the addition of new information structures to
   their respective CDDL groups.




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    +=====================+===========================+===============+
    | Map Name            | CDDL Socket               | Defined in    |
    +=====================+===========================+===============+
    | concise-swid-tag    | $$coswid-extension        | Section 2.3   |
    +---------------------+---------------------------+---------------+
    | entity-entry        | $$entity-extension        | Section 2.6   |
    +---------------------+---------------------------+---------------+
    | link-entry          | $$link-extension          | Section 2.7   |
    +---------------------+---------------------------+---------------+
    | software-meta-entry | $$software-meta-extension | Section 2.8   |
    +---------------------+---------------------------+---------------+
    | file-entry          | $$file-extension          | Section 2.9.2 |
    +---------------------+---------------------------+---------------+
    | directory-entry     | $$directory-extension     | Section 2.9.2 |
    +---------------------+---------------------------+---------------+
    | process-entry       | $$process-extension       | Section 2.9.2 |
    +---------------------+---------------------------+---------------+
    | resource-entry      | $$resource-extension      | Section 2.9.2 |
    +---------------------+---------------------------+---------------+
    | payload-entry       | $$payload-extension       | Section 2.9.3 |
    +---------------------+---------------------------+---------------+
    | evidence-entry      | $$evidence-extension      | Section 2.9.4 |
    +---------------------+---------------------------+---------------+

                Table 1: CoSWID CDDL Group Extension Points

   The CoSWID Items Registry defined in Section 6.1 provides a
   registration mechanism allowing new items, and their associated index
   values, to be added to the CoSWID model through the use of the CDDL
   sockets described in the table above.  This registration mechanism
   provides for well-known index values for data items in CoSWID
   extensions, allowing these index values to be recognized by
   implementations supporting a given extension.

   The following additional CDDL sockets are defined in this document to
   allow for adding new values to corresponding type-choices (i.e. to
   represent enumerations) via custom CDDL specifications.














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           +==================+=================+=============+
           | Enumeration Name | CDDL Socket     | Defined in  |
           +==================+=================+=============+
           | version-scheme   | $version-scheme | Section 4.1 |
           +------------------+-----------------+-------------+
           | role             | $role           | Section 4.2 |
           +------------------+-----------------+-------------+
           | ownership        | $ownership      | Section 4.3 |
           +------------------+-----------------+-------------+
           | rel              | $rel            | Section 4.4 |
           +------------------+-----------------+-------------+
           | use              | $use            | Section 4.5 |
           +------------------+-----------------+-------------+

            Table 2: CoSWID CDDL Enumeration Extension Points

   A number of CoSWID value registries are also defined in Section 6.2
   that allow new values to be registered with IANA for the enumerations
   above.  This registration mechanism supports the definition of new
   well-known index values and names for new enumeration values used by
   CoSWID, which can also be used by other software tagging
   specifications.  This registration mechanism allows new standardized
   enumerated values to be shared between multiple tagging
   specifications (and associated implementations) over time.

2.3.  The concise-swid-tag Map

   The CDDL specification for the root concise-swid-tag map is as
   follows and this rule and its constraints MUST be followed when
   creating or validating a CoSWID tag:





















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   concise-swid-tag = {
     tag-id => text / bstr .size 16,
     tag-version => integer,
     ? corpus => bool,
     ? patch => bool,
     ? supplemental => bool,
     software-name => text,
     ? software-version => text,
     ? version-scheme => $version-scheme,
     ? media => text,
     ? software-meta => one-or-more<software-meta-entry>,
     entity => one-or-more<entity-entry>,
     ? link => one-or-more<link-entry>,
     ? payload-or-evidence,
     * $$coswid-extension,
     global-attributes,
   }

   payload-or-evidence //= ( payload => payload-entry )
   payload-or-evidence //= ( evidence => evidence-entry )

   tag-id = 0
   software-name = 1
   entity = 2
   evidence = 3
   link = 4
   software-meta = 5
   payload = 6
   corpus = 8
   patch = 9
   media = 10
   supplemental = 11
   tag-version = 12
   software-version = 13
   version-scheme = 14

   $version-scheme /= multipartnumeric
   $version-scheme /= multipartnumeric-suffix
   $version-scheme /= alphanumeric
   $version-scheme /= decimal
   $version-scheme /= semver
   $version-scheme /= int / text
   multipartnumeric = 1
   multipartnumeric-suffix = 2
   alphanumeric = 3
   decimal = 4
   semver = 16384




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   The following describes each member of the concise-swid-tag root map.

   *  global-attributes: A list of items including an optional language
      definition to support the processing of text-string values and an
      unbounded set of any-attribute items.  Described in Section 2.5.

   *  tag-id (index 0): A 16 byte binary string or textual identifier
      uniquely referencing a software component.  The tag identifier
      MUST be globally unique.  If represented as a 16 byte binary
      string, the identifier MUST be a valid universally unique
      identifier as defined by [RFC4122].  There are no strict
      guidelines on how this identifier is structured, but examples
      include a 16 byte GUID (e.g. class 4 UUID) [RFC4122], or a text
      string appended to a DNS domain name to ensure uniqueness across
      organizations.

   *  tag-version (index 12): An integer value that indicate the
      specific release revision of the tag.  Typically, the initial
      value of this field is set to 0 and the value is monotonically
      increased for subsequent tags produced for the same software
      component release.  This value allows a CoSWID tag producer to
      correct an incorrect tag previously released without indicating a
      change to the underlying software component the tag represents.
      For example, the tag version could be changed to add new metadata,
      to correct a broken link, to add a missing payload entry, etc.
      When producing a revised tag, the new tag-version value MUST be
      greater than the old tag-version value.

   *  corpus (index 8): A boolean value that indicates if the tag
      identifies and describes an installable software component in its
      pre-installation state.  Installable software includes a
      installation package or installer for a software component, a
      software update, or a patch.  If the CoSWID tag represents
      installable software, the corpus item MUST be set to "true".  If
      not provided, the default value MUST be considered "false".

   *  patch (index 9): A boolean value that indicates if the tag
      identifies and describes an installed patch that has made
      incremental changes to a software component installed on an
      endpoint.  If a CoSWID tag is for a patch, the patch item MUST be
      set to "true".  If not provided, the default value MUST be
      considered "false".  A patch item's value MUST NOT be set to
      "true" if the installation of the associated software package
      changes the version of a software component.

   *  supplemental (index 11): A boolean value that indicates if the tag
      is providing additional information to be associated with another
      referenced SWID or CoSWID tag.  This allows tools and users to



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      record their own metadata about a software component without
      modifying SWID primary or patch tags created by a software
      provider.  If a CoSWID tag is a supplemental tag, the supplemental
      item MUST be set to "true".  If not provided, the default value
      MUST be considered "false".

   *  software-name (index 1): This textual item provides the software
      component's name.  This name is likely the same name that would
      appear in a package management tool.  This item maps to
      '/SoftwareIdentity/@name' in [SWID].

   *  software-version (index 13): A textual value representing the
      specific release or development version of the software component.
      This item maps to '/SoftwareIdentity/@version' in [SWID].

   *  version-scheme (index 14): An integer or textual value
      representing the versioning scheme used for the software-version
      item.  If an integer value is used it MUST be an index value in
      the range -256 to 65535.  Integer values in the range -256 to -1
      are reserved for testing and use in closed environments (see
      Section 6.2.2).  Integer values in the range 0 to 65535 correspond
      to registered entries in the IANA "Software Tag Version Scheme
      Values" registry (see Section 6.2.4.  If a string value is used it
      MUST be a private use name as defined in Section 6.2.2.  String
      values based on a Version Scheme Name from the IANA "Software Tag
      Version Scheme Values" registry MUST NOT be used, as these values
      are less concise than their index value equivalent.

   *  media (index 10): This text value is a hint to the tag consumer to
      understand what target platform this tag applies to.  This item
      item MUST be formatted as a query as defined by the W3C Media
      Queries Recommendation (see [W3C.REC-css3-mediaqueries-20120619]).
      Support for media queries are included here for interoperability
      with [SWID], which does not provide any further requirements for
      media query use.  Thus, this specification does not clarify how a
      media query is to be used for a CoSWID.

   *  software-meta (index 5): An open-ended map of key/value data
      pairs.  A number of predefined keys can be used within this item
      providing for common usage and semantics across the industry.  Use
      of this map allows any additional attribute to be included in the
      tag.  It is expected that industry groups will use a common set of
      attribute names to allow for interoperability within their
      communities.  Described in Section 2.8.  This item maps to
      '/SoftwareIdentity/Meta' in [SWID].






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   *  entity (index 2): Provides information about one or more
      organizations responsible for producing the CoSWID tag, and
      producing or releasing the software component referenced by this
      CoSWID tag.  Described in Section 2.6.

   *  link (index 4): Provides a means to establish relationship arcs
      between the tag and another items.  A given link can be used to
      establish the relationship between tags or to reference another
      resource that is related to the CoSWID tag, e.g. vulnerability
      database association, ROLIE feed [RFC8322], MUD resource
      [RFC8520], software download location, etc).  This is modeled
      after the HTML "link" element.  Described in Section 2.7.

   *  payload (index 6): This item represents a collection of software
      artifacts (described by child items) that compose the target
      software.  For example, these artifacts could be the files
      included with an installer for a corpus tag or installed on an
      endpoint when the software component is installed for a primary or
      patch tag.  The artifacts listed in a payload may be a superset of
      the software artifacts that are actually installed.  Based on user
      selections at install time, an installation might not include
      every artifact that could be created or executed on the endpoint
      when the software component is installed or run.  Described in
      Section 2.9.3.

   *  evidence (index 3): This item can be used to record the results of
      a software discovery process used to identify untagged software on
      an endpoint or to represent indicators for why software is
      believed to be installed on the endpoint.  In either case, a
      CoSWID tag can be created by the tool performing an analysis of
      the software components installed on the endpoint.  Described in
      Section 2.9.4.

   *  $$coswid-extension: This CDDL socket is used to add new
      information structures to the concise-swid-tag root map.  See
      Section 2.2.

2.4.  concise-swid-tag Co-Constraints

   The following co-constraints apply to the information provided in the
   concise-swid-tag group.

   *  The patch and supplemental items MUST NOT both be set to "true".

   *  If the patch item is set to "true", the tag SHOULD contain at
      least one link item (see Section 2.7) with both the rel item value
      of "patches" and an href item specifying an association with the
      software that was patched.



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   *  If the supplemental item is set to "true", the tag SHOULD contain
      at least one link item with both the rel item value of
      "supplemental" and an href item specifying an association with the
      software that is supplemented.

   *  If all of the corpus, patch, and supplemental items are "false",
      or if the corpus item is set to "true", then a software-version
      item MUST be included with a value set to the version of the
      software component.  This ensures that primary and corpus tags
      have an identifiable software version.

2.5.  The global-attributes Group

   The global-attributes group provides a list of items, including an
   optional language definition to support the processing of text-string
   values, and an unbounded set of any-attribute items allowing for
   additional items to be provided as a general point of extension in
   the model.

   The CDDL for the global-attributes follows:

   global-attributes = (
     ? lang => text,
     * any-attribute,
   )

   any-attribute = (
     label => one-or-more<text> / one-or-more<int>
   )

   label = text / int

   The following describes each child item of this group.

   *  lang (index 15): A textual language tag that conforms with IANA
      "Language Subtag Registry" [RFC5646].  The context of the
      specified language applies to all sibling and descendant textual
      values, unless a descendant object has defined a different
      language tag.  Thus, a new context is established when a
      descendant object redefines a new language tag.  All textual
      values within a given context MUST be considered expressed in the
      specified language.

   *  any-attribute: This sub-group provides a means to include
      arbitrary information via label/index ("key") value pairs.  Labels
      can be either a single integer or text string.  Values can be a
      single integer, a text string, or an array of integers or text
      strings.



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2.6.  The entity-entry Map

   The CDDL for the entity-entry map follows:

   entity-entry = {
     entity-name => text,
     ? reg-id => any-uri,
     role => one-or-more<$role>,
     ? thumbprint => hash-entry,
     * $$entity-extension,
     global-attributes,
   }

   entity-name = 31
   reg-id = 32
   role = 33
   thumbprint = 34

   $role /= tag-creator
   $role /= software-creator
   $role /= aggregator
   $role /= distributor
   $role /= licensor
   $role /= maintainer
   $role /= int / text
   tag-creator=1
   software-creator=2
   aggregator=3
   distributor=4
   licensor=5
   maintainer=6

   The following describes each child item of this group.

   *  global-attributes: The global-attributes group described in
      Section 2.5.

   *  entity-name (index 31): The textual name of the organizational
      entity claiming the roles specified by the role item for the
      CoSWID tag.  This item maps to '/SoftwareIdentity/Entity/@name' in
      [SWID].

   *  reg-id (index 32): The registration id value is intended to
      uniquely identify a naming authority in a given scope (e.g.
      global, organization, vendor, customer, administrative domain,
      etc.) for the referenced entity.  The value of a registration ID
      MUST be a RFC 3986 URI.  The scope SHOULD be the scope of an
      organization.



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   *  role (index 33): An integer or textual value representing the
      relationship(s) between the entity, and this tag or the referenced
      software component.  If an integer value is used it MUST be an
      index value in the range -256 to 255.  Integer values in the range
      -256 to -1 are reserved for testing and use in closed environments
      (see Section 6.2.2).  Integer values in the range 0 to 255
      correspond to registered entries in the IANA "Software Tag Entity
      Role Values" registry (see Section 6.2.5.  If a string value is
      used it MUST be a private use name as defined in Section 6.2.2.
      String values based on a Role Name from the IANA "Software Tag
      Entity Role Values" registry MUST NOT be used, as these values are
      less concise than their index value equivalent.

      The following additional requirements exist for the use of the
      "role" item:

      -  An entity item MUST be provided with the role of "tag-creator"
         for every CoSWID tag.  This indicates the organization that
         created the CoSWID tag.

      -  An entity item SHOULD be provided with the role of "software-
         creator" for every CoSWID tag, if this information is known to
         the tag creator.  This indicates the organization that created
         the referenced software component.

   *  thumbprint (index 34): The value of the thumbprint item provides a
      hash (i.e. the thumbprint) of the signing entity's public key
      certificate.  This provides an indicator of which entity signed
      the CoSWID tag, which will typically be the tag creator.  See
      Section 2.9.1 for more details on the use of the hash-entry data
      structure.

   *  $$entity-extension: This CDDL socket can be used to extend the
      entity-entry group model.  See Section 2.2.

2.7.  The link-entry Map

   The CDDL for the link-entry map follows:

   link-entry = {
     ? artifact => text,
     href => any-uri,
     ? media => text,
     ? ownership => $ownership,
     rel => $rel,
     ? media-type => text,
     ? use => $use,
     * $$link-extension,



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     global-attributes,
   }

   media = 10
   artifact = 37
   href = 38
   ownership = 39
   rel = 40
   media-type = 41
   use = 42

   $ownership /= shared
   $ownership /= private
   $ownership /= abandon
   $ownership /= int / text
   shared=1
   private=2
   abandon=3

   $rel /= ancestor
   $rel /= component
   $rel /= feature
   $rel /= installationmedia
   $rel /= packageinstaller
   $rel /= parent
   $rel /= patches
   $rel /= requires
   $rel /= see-also
   $rel /= supersedes
   $rel /= supplemental
   $rel /= -356..65536 / text
   ancestor=1
   component=2
   feature=3
   installationmedia=4
   packageinstaller=5
   parent=6
   patches=7
   requires=8
   see-also=9
   supersedes=10
   supplemental=11

   $use /= optional
   $use /= required
   $use /= recommended
   $use /= int / text
   optional=1



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   required=2
   recommended=3

   The following describes each member of this map.

   *  global-attributes: The global-attributes group described in
      Section 2.5.

   *  artifact (index: 37): To be used with rel="installation-media",
      this item's value provides the path to the installer executable or
      script that can be run to launch the referenced installation.
      Links with the same artifact name MUST be considered mirrors of
      each other, allowing the installation media to be acquired from
      any of the described sources.

   *  href (index 38): A URI-reference [RFC3986] for the referenced
      resource.  The "href" item's value can be, but is not limited to,
      the following (which is a slightly modified excerpt from [SWID]):

      -  If no URI scheme is provided, then the URI-reference is a
         relative reference relative to the URI of the CoSWID tag.  For
         example, "./folder/supplemental.coswid".

      -  a physical resource location with any acceptable URI scheme
         (e.g., file:// http:// https:// ftp://)

      -  a URI with "swid:" as the scheme refers to another SWID or
         CoSWID by the referenced tag's tag-id.  This URI needs to be
         resolved in the context of the endpoint by software that can
         lookup other SWID or CoSWID tags.  For example, "swid:2df9de35-
         0aff-4a86-ace6-f7dddd1ade4c" references the tag with the tag-id
         value "2df9de35-0aff-4a86-ace6-f7dddd1ade4c".

      -  a URI with "swidpath:" as the scheme, which refers to another
         software tag via an XPATH query [W3C.REC-xpath20-20101214].
         This scheme is provided for compatibility with [SWID].  This
         specification does not define how to resolve an XPATH query in
         the context of CBOR.

   *  media (index 10): A hint to the consumer of the link to what
      target platform the link is applicable to.  This item represents a
      query as defined by the W3C Media Queries Recommendation (see
      [W3C.REC-css3-mediaqueries-20120619]).  See also media defined in
      Section 2.3.

   *  ownership (index 39): An integer or textual value used when the
      "href" item references another software component to indicate the
      degree of ownership between the software component referenced by



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      the COSWID tag and the software component referenced by the link.
      If an integer value is used it MUST be an index value in the range
      -256 to 255.  Integer values in the range -256 to -1 are reserved
      for testing and use in closed environments (see Section 6.2.2).
      Integer values in the range 0 to 255 correspond to registered
      entries in the IANA "Software Tag Link Ownership Values" registry
      (see Section 6.2.6.  If a string value is used it MUST be a
      private use name as defined in Section 6.2.2.  String values based
      on a Ownership Type Name from the IANA "Software Tag Link
      Ownership Values" registry MUST NOT be used, as these values are
      less concise than their index value equivalent.

   *  rel (index 40): An integer or textual value that identifies the
      relationship between this CoSWID and the target resource
      identified by the "href" item.  If an integer value is used it
      MUST be an index value in the range -256 to 65535.  Integer values
      in the range -256 to -1 are reserved for testing and use in closed
      environments (see Section 6.2.2).  Integer values in the range 0
      to 65535 correspond to registered entries in the IANA "Software
      Tag Link Relationship Values" registry (see Section 6.2.7.  If a
      string value is used it MUST be either a private use name as
      defined in Section 6.2.2 or a "Relation Name" from the IANA "Link
      Relation Types" registry: https://www.iana.org/assignments/link-
      relations/link-relations.xhtml as defined by [RFC8288].  When a
      string value defined in the IANA "Software Tag Link Relationship
      Values" registry matches a Relation Name defined in the IANA "Link
      Relation Types" registry, the index value in the IANA "Software
      Tag Link Relationship Values" registry MUST be used instead, as
      this relationship has a specialized meaning in the context of a
      CoSWID tag.  String values based on a Relationship Type Name from
      the IANA "Software Tag Link Relationship Values" registry MUST NOT
      be used, as these values are less concise than their index value
      equivalent.

   *  media-type (index 41): A link can point to arbitrary resources on
      the endpoint, local network, or Internet using the href item.  Use
      of this item supplies the resource consumer with a hint of what
      type of resource to expect.  Media types are identified by
      referencing a "Name" from the IANA "Media Types" registry:
      http://www.iana.org/assignments/media-types/media-types.xhtml.
      This item maps to '/SoftwareIdentity/Link/@type' in [SWID].

   *  use (index 42): An integer or textual value used to determine if
      the referenced software component has to be installed before
      installing the software component identified by the COSWID tag.
      If an integer value is used it MUST be an index value in the range
      -256 to 255.  Integer values in the range -256 to -1 are reserved
      for testing and use in closed environments (see Section 6.2.2).



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      Integer values in the range 0 to 255 correspond to registered
      entries in the IANA "Link Use Values" registry (see Section 6.2.8.
      If a string value is used it MUST be a private use name as defined
      in Section 6.2.2.  String values based on an Link Use Type Name
      from the IANA "Software Tag Link Use Values" registry MUST NOT be
      used, as these values are less concise than their index value
      equivalent.

   *  $$link-extension: This CDDL socket can be used to extend the link-
      entry map model.  See Section 2.2.

2.8.  The software-meta-entry Map

   The CDDL for the software-meta-entry map follows:





































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   software-meta-entry = {
     ? activation-status => text,
     ? channel-type => text,
     ? colloquial-version => text,
     ? description => text,
     ? edition => text,
     ? entitlement-data-required => bool,
     ? entitlement-key => text,
     ? generator => text,
     ? persistent-id => text,
     ? product => text,
     ? product-family => text,
     ? revision => text,
     ? summary => text,
     ? unspsc-code => text,
     ? unspsc-version => text,
     * $$software-meta-extension,
     global-attributes,
   }

   activation-status = 43
   channel-type = 44
   colloquial-version = 45
   description = 46
   edition = 47
   entitlement-data-required = 48
   entitlement-key = 49
   generator = 50
   persistent-id = 51
   product = 52
   product-family = 53
   revision = 54
   summary = 55
   unspsc-code = 56
   unspsc-version = 57

   The following describes each child item of this group.

   *  global-attributes: The global-attributes group described in
      Section 2.5.

   *  activation-status (index 43): A textual value that identifies how
      the software component has been activated, which might relate to
      specific terms and conditions for its use (e.g.  Trial,
      Serialized, Licensed, Unlicensed, etc) and relate to an
      entitlement.  This attribute is typically used in supplemental
      tags as it contains information that might be selected during a
      specific install.



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   *  channel-type (index 44): A textual value that identifies which
      sales, licensing, or marketing channel the software component has
      been targeted for (e.g.  Volume, Retail, OEM, Academic, etc).
      This attribute is typically used in supplemental tags as it
      contains information that might be selected during a specific
      install.

   *  colloquial-version (index 45): A textual value for the software
      component's informal or colloquial version.  Examples may include
      a year value, a major version number, or similar value that are
      used to identify a group of specific software component releases
      that are part of the same release/support cycle.  This version can
      be the same through multiple releases of a software component,
      while the software-version specified in the concise-swid-tag group
      is much more specific and will change for each software component
      release.  This version is intended to be used for string
      comparison only and is not intended to be used to determine if a
      specific value is earlier or later in a sequence.

   *  description (index 46): A textual value that provides a detailed
      description of the software component.  This value MAY be multiple
      paragraphs separated by CR LF characters as described by
      [RFC5198].

   *  edition (index 47): A textual value indicating that the software
      component represents a functional variation of the code base used
      to support multiple software components.  For example, this item
      can be used to differentiate enterprise, standard, or professional
      variants of a software component.

   *  entitlement-data-required (index 48): A boolean value that can be
      used to determine if accompanying proof of entitlement is needed
      when a software license reconciliation process is performed.

   *  entitlement-key (index 49): A vendor-specific textual key that can
      be used to identify and establish a relationship to an
      entitlement.  Examples of an entitlement-key might include a
      serial number, product key, or license key.  For values that
      relate to a given software component install (i.e., license key),
      a supplemental tag will typically contain this information.  In
      other cases, where a general-purpose key can be provided that
      applies to all possible installs of the software component on
      different endpoints, a primary tag will typically contain this
      information.







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   *  generator (index 50): The name (or tag-id) of the software
      component that created the CoSWID tag.  If the generating software
      component has a SWID or CoSWID tag, then the tag-id for the
      generating software component SHOULD be provided.

   *  persistent-id (index 51): A globally unique identifier used to
      identify a set of software components that are related.  Software
      components sharing the same persistent-id can be different
      versions.  This item can be used to relate software components,
      released at different points in time or through different release
      channels, that may not be able to be related through use of the
      link item.

   *  product (index 52): A basic name for the software component that
      can be common across multiple tagged software components (e.g.,
      Apache HTTPD).

   *  product-family (index 53): A textual value indicating the software
      components overall product family.  This should be used when
      multiple related software components form a larger capability that
      is installed on multiple different endpoints.  For example, some
      software families may consist of server, client, and shared
      service components that are part of a larger capability.  Email
      systems, enterprise applications, backup services, web
      conferencing, and similar capabilities are examples of families.
      Use of this item is not intended to represent groups of software
      that are bundled or installed together.  The persistent-id or link
      items SHOULD be used to relate bundled software components.

   *  revision (index 54): A string value indicating an informal or
      colloquial release version of the software.  This value can
      provide a different version value as compared to the software-
      version specified in the concise-swid-tag group.  This is useful
      when one or more releases need to have an informal version label
      that differs from the specific exact version value specified by
      software-version.  Examples can include SP1, RC1, Beta, etc.

   *  summary (index 55): A short description of the software component.
      This MUST be a single sentence suitable for display in a user
      interface.

   *  unspsc-code (index 56): An 8 digit UNSPSC classification code for
      the software component as defined by the United Nations Standard
      Products and Services Code (UNSPSC, [UNSPSC]).

   *  unspsc-version (index 57): The version of UNSPSC used to define
      the unspsc-code value.




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   *  $$meta-extension: This CDDL socket can be used to extend the
      software-meta-entry group model.  See Section 2.2.

2.9.  The Resource Collection Definition

2.9.1.  The hash-entry Array

   CoSWID adds explicit support for the representation of hash entries
   using algorithms that are registered in the IANA "Named Information
   Hash Algorithm Registry" [NIHAR] using the hash member (index 7) and
   the corresponding hash-entry type.  This is the equivalent of the
   namespace qualified "hash" attribute in [SWID].

   hash-entry = [
     hash-alg-id: int,
     hash-value: bytes,
   ]

   The number used as a value for hash-alg-id is an integer-based hash
   algorithm identifier who's value MUST refer to an ID in the IANA
   "Named Information Hash Algorithm Registry" [NIHAR] with a Status of
   "current"; other hash algorithms MUST NOT be used.  If the hash-alg-
   id is not known, then the integer value "0" MUST be used.  This
   ensures parity between the SWID tag specification [SWID], which does
   not allow an algorithm to be identified for this field.

   The hash-value byte string value MUST represent the raw hash value of
   the hashed resource generated using the hash algorithm indicated by
   the hash-alg-id.

2.9.2.  The resource-collection Group

   A list of items both used in evidence (created by a software
   discovery process) and payload (installed in an endpoint) content of
   a CoSWID tag document to structure and differentiate the content of
   specific CoSWID tag types.  Potential content includes directories,
   files, processes, or resources.

   The CDDL for the resource-collection group follows:

   path-elements-group = ( ? directory => one-or-more<directory-entry>,
                           ? file => one-or-more<file-entry>,
                         )

   resource-collection = (
     path-elements-group,
     ? process => one-or-more<process-entry>,
     ? resource => one-or-more<resource-entry>,



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     * $$resource-collection-extension,
   )

   filesystem-item = (
     ? key => bool,
     ? location => text,
     fs-name => text,
     ? root => text,
   )

   file-entry = {
     filesystem-item,
     ? size => uint,
     ? file-version => text,
     ? hash => hash-entry,
     * $$file-extension,
     global-attributes,
   }

   directory-entry = {
     filesystem-item,
     ? path-elements => { path-elements-group },
     * $$directory-extension,
     global-attributes,
   }

   process-entry = {
     process-name => text,
     ? pid => integer,
     * $$process-extension,
     global-attributes,
   }

   resource-entry = {
     type => text,
     * $$resource-extension,
     global-attributes,
   }

   directory = 16
   file = 17
   process = 18
   resource = 19
   size = 20
   file-version = 21
   key = 22
   location = 23
   fs-name = 24



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   root = 25
   path-elements = 26
   process-name = 27
   pid = 28
   type = 29

   The following describes each member of the groups and maps
   illustrated above.

   *  filesystem-item: A list of common items used for representing the
      filesystem root, relative location, name, and significance of a
      file or directory item.

   *  global-attributes: The global-attributes group described in
      Section 2.5.

   *  directory (index 16): A directory item allows child directory and
      file items to be defined within a directory hierarchy for the
      software component.

   *  file (index 17): A file item allows details about a file to be
      provided for the software component.

   *  process (index 18): A process item allows details to be provided
      about the runtime behavior of the software component, such as
      information that will appear in a process listing on an endpoint.

   *  resource (index 19): A resource item can be used to provide
      details about an artifact or capability expected to be found on an
      endpoint or evidence collected related to the software component.
      This can be used to represent concepts not addressed directly by
      the directory, file, or process items.  Examples include: registry
      keys, bound ports, etc.  The equivalent construct in [SWID] is
      currently under specified.  As a result, this item might be
      further defined through extension in the future.

   *  size (index 20): The file's size in bytes.

   *  file-version (index 21): The file's version as reported by
      querying information on the file from the operating system.  This
      item maps to '/SoftwareIdentity/(Payload|Evidence)/File/@version'
      in [SWID].

   *  hash (index 7): A hash of the file as described in Section 2.9.1.







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   *  key (index 22): A boolean value indicating if a file or directory
      is significant or required for the software component to execute
      or function properly.  These are files or directories that can be
      used to affirmatively determine if the software component is
      installed on an endpoint.

   *  location (index 23): The filesystem path where a file is expected
      to be located when installed or copied.  The location MUST be
      either relative to the location of the parent directory item
      (preferred) or relative to the location of the CoSWID tag if no
      parent is defined.  The location MUST NOT include a file's name,
      which is provided by the fs-name item.

   *  fs-name (index 24): The name of the directory or file without any
      path information.  This aligns with a file "name" in [SWID].  This
      item maps to
      '/SoftwareIdentity/(Payload|Evidence)/(File|Directory)/@name' in
      [SWID].

   *  root (index 25): A filesystem-specific name for the root of the
      filesystem.  The location item is considered relative to this
      location if specified.  If not provided, the value provided by the
      location item is expected to be relative to its parent or the
      location of the CoSWID tag if no parent is provided.

   *  path-elements (index 26): This group allows a hierarchy of
      directory and file items to be defined in payload or evidence
      items.  This is a construction within the CDDL definition of
      CoSWID to support shared syntax and does not appear in [SWID].

   *  process-name (index 27): The software component's process name as
      it will appear in an endpoint's process list.  This aligns with a
      process "name" in [SWID].  This item maps to
      '/SoftwareIdentity/(Payload|Evidence)/Process/@name' in [SWID].

   *  pid (index 28): The process ID identified for a running instance
      of the software component in the endpoint's process list.  This is
      used as part of the evidence item.

   *  type (index 29): A string indicating the type of resource.

   *  $$resource-collection-extension: This CDDL socket can be used to
      extend the resource-collection group model.  This can be used to
      add new specialized types of resources.  See Section 2.2.

   *  $$file-extension: This CDDL socket can be used to extend the file-
      entry group model.  See Section 2.2.




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   *  $$directory-extension: This CDDL socket can be used to extend the
      directory-entry group model.  See Section 2.2.

   *  $$process-extension: This CDDL socket can be used to extend the
      process-entry group model.  See Section 2.2.

   *  $$resource-extension: This CDDL socket can be used to extend the
      resource-entry group model.  See Section 2.2.

2.9.3.  The payload-entry Map

   The CDDL for the payload-entry map follows:

   payload-entry = {
     resource-collection,
     * $$payload-extension,
     global-attributes,
   }

   The following describes each child item of this group.

   *  global-attributes: The global-attributes group described in
      Section 2.5.

   *  resource-collection: The resource-collection group described in
      Section 2.9.2.

   *  $$payload-extension: This CDDL socket can be used to extend the
      payload-entry group model.  See Section 2.2.

2.9.4.  The evidence-entry Map

   The CDDL for the evidence-entry map follows:

   evidence-entry = {
     resource-collection,
     ? date => integer-time,
     ? device-id => text,
     * $$evidence-extension,
     global-attributes,
   }

   date = 35
   device-id = 36

   The following describes each child item of this group.





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   *  global-attributes: The global-attributes group described in
      Section 2.5.

   *  resource-collection: The resource-collection group described in
      Section 2.9.2.

   *  date (index 35): The date and time the information was collected
      pertaining to the evidence item.

   *  device-id (index 36): The endpoint's string identifier from which
      the evidence was collected.

   *  $$evidence-extension: This CDDL socket can be used to extend the
      evidence-entry group model.  See Section 2.2.

2.10.  Full CDDL Specification

   In order to create a valid CoSWID document the structure of the
   corresponding CBOR message MUST adhere to the following CDDL
   specification.

   concise-swid-tag = {
     tag-id => text / bstr .size 16,
     tag-version => integer,
     ? corpus => bool,
     ? patch => bool,
     ? supplemental => bool,
     software-name => text,
     ? software-version => text,
     ? version-scheme => $version-scheme,
     ? media => text,
     ? software-meta => one-or-more<software-meta-entry>,
     entity => one-or-more<entity-entry>,
     ? link => one-or-more<link-entry>,
     ? payload-or-evidence,
     * $$coswid-extension,
     global-attributes,
   }

   payload-or-evidence //= ( payload => payload-entry )
   payload-or-evidence //= ( evidence => evidence-entry )

   any-uri = uri
   label = text / int

   $version-scheme /= multipartnumeric
   $version-scheme /= multipartnumeric-suffix
   $version-scheme /= alphanumeric



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   $version-scheme /= decimal
   $version-scheme /= semver
   $version-scheme /= int / text

   any-attribute = (
     label => one-or-more<text> / one-or-more<int>
   )

   one-or-more<T> = T / [ 2* T ]

   global-attributes = (
     ? lang => text,
     * any-attribute,
   )

   hash-entry = [
     hash-alg-id: int,
     hash-value: bytes,
   ]

   entity-entry = {
     entity-name => text,
     ? reg-id => any-uri,
     role => one-or-more<$role>,
     ? thumbprint => hash-entry,
     * $$entity-extension,
     global-attributes,
   }

   $role /= tag-creator
   $role /= software-creator
   $role /= aggregator
   $role /= distributor
   $role /= licensor
   $role /= maintainer
   $role /= int / text

   link-entry = {
     ? artifact => text,
     href => any-uri,
     ? media => text,
     ? ownership => $ownership,
     rel => $rel,
     ? media-type => text,
     ? use => $use,
     * $$link-extension,
     global-attributes,
   }



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   $ownership /= shared
   $ownership /= private
   $ownership /= abandon
   $ownership /= int / text

   $rel /= ancestor
   $rel /= component
   $rel /= feature
   $rel /= installationmedia
   $rel /= packageinstaller
   $rel /= parent
   $rel /= patches
   $rel /= requires
   $rel /= see-also
   $rel /= supersedes
   $rel /= supplemental
   $rel /= -256..64436 / text

   $use /= optional
   $use /= required
   $use /= recommended
   $use /= int / text

   software-meta-entry = {
     ? activation-status => text,
     ? channel-type => text,
     ? colloquial-version => text,
     ? description => text,
     ? edition => text,
     ? entitlement-data-required => bool,
     ? entitlement-key => text,
     ? generator => text,
     ? persistent-id => text,
     ? product => text,
     ? product-family => text,
     ? revision => text,
     ? summary => text,
     ? unspsc-code => text,
     ? unspsc-version => text,
     * $$software-meta-extension,
     global-attributes,
   }

   path-elements-group = ( ? directory => one-or-more<directory-entry>,
                           ? file => one-or-more<file-entry>,
                         )

   resource-collection = (



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     path-elements-group,
     ? process => one-or-more<process-entry>,
     ? resource => one-or-more<resource-entry>,
     * $$resource-collection-extension,
   )

   file-entry = {
     filesystem-item,
     ? size => uint,
     ? file-version => text,
     ? hash => hash-entry,
     * $$file-extension,
     global-attributes,
   }

   directory-entry = {
     filesystem-item,
     ? path-elements => { path-elements-group },
     * $$directory-extension,
     global-attributes,
   }

   process-entry = {
     process-name => text,
     ? pid => integer,
     * $$process-extension,
     global-attributes,
   }

   resource-entry = {
     type => text,
     * $$resource-extension,
     global-attributes,
   }

   filesystem-item = (
     ? key => bool,
     ? location => text,
     fs-name => text,
     ? root => text,
   )

   payload-entry = {
     resource-collection,
     * $$payload-extension,
     global-attributes,
   }




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   evidence-entry = {
     resource-collection,
     ? date => integer-time,
     ? device-id => text,
     * $$evidence-extension,
     global-attributes,
   }

   integer-time = #6.1(int)

   ; "global map member" integer indexes
   tag-id = 0
   software-name = 1
   entity = 2
   evidence = 3
   link = 4
   software-meta = 5
   payload = 6
   hash = 7
   corpus = 8
   patch = 9
   media = 10
   supplemental = 11
   tag-version = 12
   software-version = 13
   version-scheme = 14
   lang = 15
   directory = 16
   file = 17
   process = 18
   resource = 19
   size = 20
   file-version = 21
   key = 22
   location = 23
   fs-name = 24
   root = 25
   path-elements = 26
   process-name = 27
   pid = 28
   type = 29
   entity-name = 31
   reg-id = 32
   role = 33
   thumbprint = 34
   date = 35
   device-id = 36
   artifact = 37



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   href = 38
   ownership = 39
   rel = 40
   media-type = 41
   use = 42
   activation-status = 43
   channel-type = 44
   colloquial-version = 45
   description = 46
   edition = 47
   entitlement-data-required = 48
   entitlement-key = 49
   generator = 50
   persistent-id = 51
   product = 52
   product-family = 53
   revision = 54
   summary = 55
   unspsc-code = 56
   unspsc-version = 57

   ; "version-scheme" integer indexes
   multipartnumeric = 1
   multipartnumeric-suffix = 2
   alphanumeric = 3
   decimal = 4
   semver = 16384

   ; "role" integer indexes
   tag-creator=1
   software-creator=2
   aggregator=3
   distributor=4
   licensor=5
   maintainer=6

   ; "ownership" integer indexes
   shared=1
   private=2
   abandon=3

   ; "rel" integer indexes
   ancestor=1
   component=2
   feature=3
   installationmedia=4
   packageinstaller=5
   parent=6



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   patches=7
   requires=8
   see-also=9
   supersedes=10
   ; supplemental=11 ; this is already defined earlier

   ; "use" integer indexes
   optional=1
   required=2
   recommended=3

3.  Determining the Type of CoSWID

   The operational model for SWID and CoSWID tags was introduced in
   Section 1.1, which described four different CoSWID tag types.  The
   following additional rules apply to the use of CoSWID tags to ensure
   that created tags properly identify the tag type.

   The first matching rule MUST determine the type of the CoSWID tag.

   1.  Primary Tag: A CoSWID tag MUST be considered a primary tag if the
       corpus, patch, and supplemental items are "false".

   2.  Supplemental Tag: A CoSWID tag MUST be considered a supplemental
       tag if the supplemental item is set to "true".

   3.  Corpus Tag: A CoSWID tag MUST be considered a corpus tag if the
       corpus item is "true".

   4.  Patch Tag: A CoSWID tag MUST be considered a patch tag if the
       patch item is "true".

   Note: Multiple of the corpus, patch, and supplemental items can have
   values set as "true".  The rules above provide a means to determine
   the tag's type in such a case.  For example, a SWID or CoSWID tag for
   a patch installer might have both corpus and patch items set to
   "true".  In such a case, the tag is a "Corpus Tag".  The tag
   installed by this installer would have only the patch item set to
   "true", making the installed tag type a "Patch Tag".

4.  CoSWID Indexed Label Values










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4.1.  Version Scheme

   The following table contains a set of values for use in the concise-
   swid-tag group's version-scheme item.  These values match the version
   schemes defined in the ISO/IEC 19770-2:2015 [SWID] specification.
   Index value indicates the value to use as the version-scheme item's
   value.  The Version Scheme Name provides human-readable text for the
   value.  The Definition describes the syntax of allowed values for
   each entry.

   +=======+=========================+================================+
   | Index | Version Scheme Name     | Definition                     |
   +=======+=========================+================================+
   | 1     | multipartnumeric        | Numbers separated by dots,     |
   |       |                         | where the numbers are          |
   |       |                         | interpreted as integers (e.g., |
   |       |                         | 1.2.3, 1.4.5, 1.2.3.4.5.6.7)   |
   +-------+-------------------------+--------------------------------+
   | 2     | multipartnumeric+suffix | Numbers separated by dots,     |
   |       |                         | where the numbers are          |
   |       |                         | interpreted as integers with   |
   |       |                         | an additional textual suffix   |
   |       |                         | (e.g., 1.2.3a)                 |
   +-------+-------------------------+--------------------------------+
   | 3     | alphanumeric            | Strictly a string, sorting is  |
   |       |                         | done alphanumerically          |
   +-------+-------------------------+--------------------------------+
   | 4     | decimal                 | A floating point number (e.g., |
   |       |                         | 1.25 is less than 1.3)         |
   +-------+-------------------------+--------------------------------+
   | 16384 | semver                  | Follows the [SEMVER]           |
   |       |                         | specification                  |
   +-------+-------------------------+--------------------------------+

                      Table 3: Version Scheme Values

   The values above are registered in the IANA "Software Tag Version
   Scheme Values" registry defined in Section Section 6.2.4.  Additional
   entries will likely be registered over time in this registry.

   These version schemes have partially overlapping value spaces.  The
   following guidelines help to ensure that the most specific version-
   scheme is used:

   *  "decimal" and "multipartnumeric" partially overlap in their value
      space when a value matches a decimal number.  When a corresponding
      software-version item's value falls within this overlapping value
      space, the "decimal" version scheme SHOULD be used.



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   *  "multipartnumeric" and "semver" partially overlap in their value
      space when a "multipartnumeric" value matches the semantic
      versioning syntax.  When a corresponding software-version item's
      value falls within this overlapping value space, the "semver"
      version scheme SHOULD be used.

   *  "alphanumeric" and other version schemes might overlap in their
      value space.  When a corresponding software-version item's value
      falls within this overlapping value space, the other version
      scheme SHOULD be used instead of "alphanumeric".

4.2.  Entity Role Values

   The following table indicates the index value to use for the entity-
   entry group's role item (see Section 2.6).  These values match the
   entity roles defined in the ISO/IEC 19770-2:2015 [SWID]
   specification.  The "Index" value indicates the value to use as the
   role item's value.  The "Role Name" provides human-readable text for
   the value.  The "Definition" describes the semantic meaning of each
   entry.































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   +=======+=================+========================================+
   | Index | Role Name       | Definition                             |
   +=======+=================+========================================+
   | 1     | tagCreator      | The person or organization that        |
   |       |                 | created the containing SWID or CoSWID  |
   |       |                 | tag                                    |
   +-------+-----------------+----------------------------------------+
   | 2     | softwareCreator | The person or organization entity that |
   |       |                 | created the software component.        |
   +-------+-----------------+----------------------------------------+
   | 3     | aggregator      | From [SWID], "An organization or       |
   |       |                 | system that encapsulates software from |
   |       |                 | their own and/or other organizations   |
   |       |                 | into a different distribution process  |
   |       |                 | (as in the case of virtualization), or |
   |       |                 | as a completed system to accomplish a  |
   |       |                 | specific task (as in the case of a     |
   |       |                 | value added reseller)."                |
   +-------+-----------------+----------------------------------------+
   | 4     | distributor     | From [SWID], "An entity that furthers  |
   |       |                 | the marketing, selling and/or          |
   |       |                 | distribution of software from the      |
   |       |                 | original place of manufacture to the   |
   |       |                 | ultimate user without modifying the    |
   |       |                 | software, its packaging or its         |
   |       |                 | labelling."                            |
   +-------+-----------------+----------------------------------------+
   | 5     | licensor        | From [SAM] as "software licensor", a   |
   |       |                 | "person or organization who owns or    |
   |       |                 | holds the rights to issue a software   |
   |       |                 | license for a specific software        |
   |       |                 | [component]"                           |
   +-------+-----------------+----------------------------------------+
   | 6     | maintainer      | The person or organization that is     |
   |       |                 | responsible for coordinating and       |
   |       |                 | making updates to the source code for  |
   |       |                 | the software component.  This SHOULD   |
   |       |                 | be used when the "maintainer" is a     |
   |       |                 | different person or organization than  |
   |       |                 | the original "softwareCreator".        |
   +-------+-----------------+----------------------------------------+

                       Table 4: Entity Role Values








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   The values above are registered in the IANA "Software Tag Entity Role
   Values" registry defined in Section 6.2.5.  Additional values will
   likely be registered over time.  Additionally, the index values 128
   through 255 and the name prefix "x_" have been reserved for private
   use.

4.3.  Link Ownership Values

   The following table indicates the index value to use for the link-
   entry group's ownership item (see Section 2.7).  These values match
   the link ownership values defined in the ISO/IEC 19770-2:2015 [SWID]
   specification.  The "Index" value indicates the value to use as the
   link-entry group ownership item's value.  The "Ownership Type"
   provides human-readable text for the value.  The "Definition"
   describes the semantic meaning of each entry.

   +=======+===========+===============================================+
   | Index | Ownership | Definition                                    |
   |       | Type      |                                               |
   +=======+===========+===============================================+
   | 1     | abandon   | If the software component referenced by the   |
   |       |           | CoSWID tag is uninstalled, then the           |
   |       |           | referenced software SHOULD NOT be             |
   |       |           | uninstalled                                   |
   +-------+-----------+-----------------------------------------------+
   | 2     | private   | If the software component referenced by the   |
   |       |           | CoSWID tag is uninstalled, then the           |
   |       |           | referenced software SHOULD be uninstalled as  |
   |       |           | well.                                         |
   +-------+-----------+-----------------------------------------------+
   | 3     | shared    | If the software component referenced by the   |
   |       |           | CoSWID tag is uninstalled, then the           |
   |       |           | referenced software SHOULD be uninstalled if  |
   |       |           | no other components sharing the software.     |
   +-------+-----------+-----------------------------------------------+

                       Table 5: Link Ownership Values

   The values above are registered in the IANA "Software Tag Link
   Ownership Values" registry defined in Section 6.2.6.  Additional
   values will likely be registered over time.  Additionally, the index
   values 128 through 255 and the name prefix "x_" have been reserved
   for private use.








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4.4.  Link Rel Values

   The following table indicates the index value to use for the link-
   entry group's rel item (see Section 2.7).  These values match the
   link rel values defined in the ISO/IEC 19770-2:2015 [SWID]
   specification.  The "Index" value indicates the value to use as the
   link-entry group ownership item's value.  The "Relationship Type"
   provides human-readable text for the value.  The "Definition"
   describes the semantic meaning of each entry.

   +=======+===================+=======================================+
   | Index | Relationship Type | Definition                            |
   +=======+===================+=======================================+
   | 1     | ancestor          | The link references a software        |
   |       |                   | tag for a previous release of         |
   |       |                   | this software.  This can be           |
   |       |                   | useful to define an upgrade path.     |
   +-------+-------------------+---------------------------------------+
   | 2     | component         | The link references a software        |
   |       |                   | tag for a separate component of       |
   |       |                   | this software.                        |
   +-------+-------------------+---------------------------------------+
   | 3     | feature           | The link references a                 |
   |       |                   | configurable feature of this          |
   |       |                   | software that can be enabled or       |
   |       |                   | disabled without changing the         |
   |       |                   | installed files.                      |
   +-------+-------------------+---------------------------------------+
   | 4     | installationmedia | The link references the               |
   |       |                   | installation package that can be      |
   |       |                   | used to install this software.        |
   +-------+-------------------+---------------------------------------+
   | 5     | packageinstaller  | The link references the               |
   |       |                   | installation software needed to       |
   |       |                   | install this software.                |
   +-------+-------------------+---------------------------------------+
   | 6     | parent            | The link references a software        |
   |       |                   | tag that is the parent of the         |
   |       |                   | referencing tag.  This                |
   |       |                   | relationship can be used when         |
   |       |                   | multiple software components are      |
   |       |                   | part of a software bundle, where      |
   |       |                   | the "parent" is the software tag      |
   |       |                   | for the bundle, and each child is     |
   |       |                   | a "component".  In such a case,       |
   |       |                   | each child component can provide      |
   |       |                   | a "parent" link relationship to       |
   |       |                   | the bundle's software tag, and        |



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   |       |                   | the bundle can provide a              |
   |       |                   | "component" link relationship to      |
   |       |                   | each child software component.        |
   +-------+-------------------+---------------------------------------+
   | 7     | patches           | The link references a software        |
   |       |                   | tag that the referencing software     |
   |       |                   | patches.  Typically only used for     |
   |       |                   | patch tags (see Section 1.1).         |
   +-------+-------------------+---------------------------------------+
   | 8     | requires          | The link references a                 |
   |       |                   | prerequisite for installing this      |
   |       |                   | software.  A patch tag (see           |
   |       |                   | Section 1.1) can use this to          |
   |       |                   | represent base software or            |
   |       |                   | another patch that needs to be        |
   |       |                   | installed first.                      |
   +-------+-------------------+---------------------------------------+
   | 9     | see-also          | The link references other             |
   |       |                   | software that may be of interest      |
   |       |                   | that relates to this software.        |
   +-------+-------------------+---------------------------------------+
   | 10    | supersedes        | The link references another           |
   |       |                   | software that this software           |
   |       |                   | replaces.  A patch tag (see           |
   |       |                   | Section 1.1) can use this to          |
   |       |                   | represent another patch that this     |
   |       |                   | patch incorporates or replaces.       |
   +-------+-------------------+---------------------------------------+
   | 11    | supplemental      | The link references a software        |
   |       |                   | tag that the referencing tag          |
   |       |                   | supplements.  Used on                 |
   |       |                   | supplemental tags (see                |
   |       |                   | Section 1.1).                         |
   +-------+-------------------+---------------------------------------+

                     Table 6: Link Relationship Values

   The values above are registered in the IANA "Software Tag Link
   Relationship Values" registry defined in Section 6.2.7.  Additional
   values will likely be registered over time.  Additionally, the index
   values 32768 through 65535 and the name prefix "x_" have been
   reserved for private use.









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4.5.  Link Use Values

   The following table indicates the index value to use for the link-
   entry group's use item (see Section 2.7).  These values match the
   link use values defined in the ISO/IEC 19770-2:2015 [SWID]
   specification.  The "Index" value indicates the value to use as the
   link-entry group use item's value.  The "Use Type" provides human-
   readable text for the value.  The "Definition" describes the semantic
   meaning of each entry.

     +=======+=============+========================================+
     | Index | Use Type    | Definition                             |
     +=======+=============+========================================+
     | 1     | optional    | From [SWID], "Not absolutely required; |
     |       |             | the [Link]'d software is installed     |
     |       |             | only when specified."                  |
     +-------+-------------+----------------------------------------+
     | 2     | required    | From [SWID], "The [Link]'d software is |
     |       |             | absolutely required for an operation   |
     |       |             | software installation."                |
     +-------+-------------+----------------------------------------+
     | 3     | recommended | From [SWID], "Not absolutely required; |
     |       |             | the [Link]'d software is installed     |
     |       |             | unless specified otherwise."           |
     +-------+-------------+----------------------------------------+

                         Table 7: Link Use Values

   The values above are registered in the IANA "Software Tag Link Use
   Values" registry defined in Section 6.2.8.  Additional values will
   likely be registered over time.  Additionally, the index values 128
   through 255 and the name prefix "x_" have been reserved for private
   use.

5.  URI Schemes

   This specification defines the following URI schemes for use in
   CoSWID and to provide interoperability with schemes used in {SWID}.

   Note: These schemes are used in {SWID} without an IANA registration.
   This specification ensures that these schemes are properly defined
   going forward.









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5.1.  "swid" URI Scheme Specification

   URIs specifying the "swid" scheme are used to reference a software
   tag by its tag-id.  A tag-id referenced in this way can be used to
   identify the tag resource in the context of where it is referenced
   from.  For example, when a tag is installed on a given device, that
   tag can reference related tags on the same device using URIs with
   this scheme.

   For URIs that use the "swid" scheme, the scheme specific part MUST
   consist of a referenced software tag's tag-id.  This tag-id MUST be
   URI encoded according to [RFC3986] Section 2.1.

   The following expression is a valid example:

   swid:2df9de35-0aff-4a86-ace6-f7dddd1ade4c

5.2.  "swidpath" URI Scheme Specification

   URIs specifying the "swidpath" scheme are used to reference the data
   that must be found in a given software tag for that tag to be
   considered a matching tag to be included in the identified tag
   collection.  Tags to be evaluated include all tags in the context of
   where the tag is referenced from.  For example, when a tag is
   installed on a given device, that tag can reference related tags on
   the same device using a URI with this scheme.

   For URIs that use the "swidpath" scheme, the requirements apply.

   The scheme specific part MUST be an XPath expression as defined by
   [W3C.REC-xpath20-20101214].  The included XPath expression will be
   URI encoded according to [RFC3986] Section 2.1.

   This XPath is evaluated over SWID tags found on a system.  A given
   tag MUST be considered a match if the XPath evaluation result value
   has an effective boolean value of "true" according to
   [W3C.REC-xpath20-20101214] Section 2.4.3.

6.  IANA Considerations

   This document has a number of IANA considerations, as described in
   the following subsections.  In summary, 6 new registries are
   established with this request, with initial entries provided for each
   registry.  New values for 5 other registries are also requested.







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6.1.  CoSWID Items Registry

   This registry uses integer values as index values in CBOR maps.

   This document defines a new registry titled "CoSWID Items".  Future
   registrations for this registry are to be made based on [RFC8126] as
   follows:

              +==================+=========================+
              | Range            | Registration Procedures |
              +==================+=========================+
              | 0-32767          | Standards Action        |
              +------------------+-------------------------+
              | 32768-4294967295 | Specification Required  |
              +------------------+-------------------------+

              Table 8: CoSWID Items Registration Procedures

   All negative values are reserved for Private Use.

   Initial registrations for the "CoSWID Items" registry are provided
   below.  Assignments consist of an integer index value, the item name,
   and a reference to the defining specification.

       +===============+===========================+===============+
       | Index         | Item Name                 | Specification |
       +===============+===========================+===============+
       | 0             | tag-id                    | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 1             | software-name             | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 2             | entity                    | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 3             | evidence                  | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 4             | link                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 5             | software-meta             | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 6             | payload                   | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 7             | hash                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 8             | corpus                    | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 9             | patch                     | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 10            | media                     | RFC-AAAA      |



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       +---------------+---------------------------+---------------+
       | 11            | supplemental              | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 12            | tag-version               | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 13            | software-version          | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 14            | version-scheme            | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 15            | lang                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 16            | directory                 | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 17            | file                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 18            | process                   | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 19            | resource                  | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 20            | size                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 21            | file-version              | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 22            | key                       | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 23            | location                  | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 24            | fs-name                   | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 25            | root                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 26            | path-elements             | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 27            | process-name              | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 28            | pid                       | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 29            | type                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 31            | entity-name               | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 32            | reg-id                    | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 33            | role                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 34            | thumbprint                | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 35            | date                      | RFC-AAAA      |



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       +---------------+---------------------------+---------------+
       | 36            | device-id                 | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 37            | artifact                  | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 38            | href                      | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 39            | ownership                 | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 40            | rel                       | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 41            | media-type                | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 42            | use                       | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 43            | activation-status         | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 44            | channel-type              | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 45            | colloquial-version        | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 46            | description               | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 47            | edition                   | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 48            | entitlement-data-required | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 49            | entitlement-key           | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 50            | generator                 | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 51            | persistent-id             | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 52            | product                   | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 53            | product-family            | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 54            | revision                  | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 55            | summary                   | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 56            | unspsc-code               | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 57            | unspsc-version            | RFC-AAAA      |
       +---------------+---------------------------+---------------+
       | 58-4294967295 | Unassigned                |               |
       +---------------+---------------------------+---------------+




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                 Table 9: CoSWID Items Inital Registrations

6.2.  Software Tag Values Registries

   The following IANA registries provide a mechanism for new values to
   be added over time to common enumerations used by SWID and CoSWID.

6.2.1.  Registration Procedures

   The following registries allow for the registration of index values
   and names.  New registrations will be permitted through either the
   Standards Action policy or the Specification Required policy [BCP26].
   New index values will be provided on a First Come First Served as
   defined by [BCP26].

   The following registries also reserve the integer-based index values
   in the range of -1 to -256 for private use as defined by [BCP26] in
   Section 4.1.  This allows values -1 to -24 to be expressed as a
   single uint_8t in CBOR, and values -25 to -256 to be expressed using
   an additional uint_8t in CBOR.

6.2.2.  Private Use of Index and Name Values

   The integer-based index values in the private use range (-1 to -256)
   are intended for testing purposes and closed environments; values in
   other ranges SHOULD NOT be assigned for testing.

   For names that correspond to private use index values, an
   Internationalized Domain Name prefix MUST be used to prevent name
   conflicts using the form:

   "domain.prefix-name"

   Where "domain.prefix" MUST be a valid Internationalized Domain Name
   as defined by [RFC5892], and "name" MUST be a unique name within the
   namespace defined by the "domain.prefix".  Use of a prefix in this
   way allows for a name to be used initially in the private use range,
   and to be registered at a future point in time.  This is consistent
   with the guidance in [BCP178].

6.2.3.  Expert Review Guidelines

   Designated experts MUST ensure that new registration requests meet
   the following additional guidelines:







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   *  The requesting specification MUST provide a clear semantic
      definition for the new entry.  This definition MUST clearly
      differentiate the requested entry from other previously registered
      entries.

   *  The requesting specification MUST describe the intended use of the
      entry, including any co-constraints that exist between the use of
      the entry's index value or name, and other values defined within
      the SWID/CoSWID model.

   *  Index values and names outside the private use space MUST NOT be
      used without registration.  This is considered squatting and
      SHOULD be avoided.  Designated experts MUST ensure that reviewed
      specifications register all appropriate index values and names.

   *  Standards track documents MAY include entries registered in the
      range reserved for entries under the Specification Required
      policy.  This can occur when a standards track document provides
      further guidance on the use of index values and names that are in
      common use, but were not registered with IANA.  This situation
      SHOULD be avoided.

   *  All registered names MUST be valid according to the XML Schema
      NMTOKEN data type (see [W3C.REC-xmlschema-2-20041028]
      Section 3.3.4).  This ensures that registered names are compatible
      with the SWID format [SWID] where they are used.

   *  Registration of vanity names SHOULD be discouraged.  The
      requesting specification MUST provide a description of how a
      requested name will allow for use by multiple stakeholders.

6.2.4.  Software Tag Version Scheme Values Registry

   This document establishes a new registry titled "Software Tag Version
   Scheme Values".  This registry provides index values for use as
   version-scheme item values in this document and version scheme names
   for use in [SWID].

   [TO BE REMOVED: This registration should take place at the following
   location: https://www.iana.org/assignments/swid]

   This registry uses the registration procedures defined in
   Section 6.2.1 with the following associated ranges:








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                 +=============+=========================+
                 | Range       | Registration Procedures |
                 +=============+=========================+
                 | 0-16383     | Standards Action        |
                 +-------------+-------------------------+
                 | 16384-65535 | Specification Required  |
                 +-------------+-------------------------+

                      Table 10: CoSWID Version Scheme
                          Registration Procedures

   Assignments MUST consist of an integer Index value, the Version
   Scheme Name, and a reference to the defining specification.

   Initial registrations for the "Software Tag Version Scheme Values"
   registry are provided below, which are derived from the textual
   version scheme names defined in [SWID].

        +=============+=========================+=================+
        | Index       | Version Scheme Name     | Specification   |
        +=============+=========================+=================+
        | 0           | Reserved                |                 |
        +-------------+-------------------------+-----------------+
        | 1           | multipartnumeric        | See Section 4.1 |
        +-------------+-------------------------+-----------------+
        | 2           | multipartnumeric+suffix | See Section 4.1 |
        +-------------+-------------------------+-----------------+
        | 3           | alphanumeric            | See Section 4.1 |
        +-------------+-------------------------+-----------------+
        | 4           | decimal                 | See Section 4.1 |
        +-------------+-------------------------+-----------------+
        | 5-16383     | Unassigned              |                 |
        +-------------+-------------------------+-----------------+
        | 16384       | semver                  | [SEMVER]        |
        +-------------+-------------------------+-----------------+
        | 16385-65535 | Unassigned              |                 |
        +-------------+-------------------------+-----------------+

           Table 11: CoSWID Version Scheme Initial Registrations

   Registrations MUST conform to the expert review guidelines defined in
   Section 6.2.3.









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   Designated experts MUST also ensure that newly requested entries
   define a value space for the corresponding version item that is
   unique from other previously registered entries.  Note: The initial
   registrations violate this requirement, but are included for
   backwards compatibility with [SWID].  Guidelines on how to deconflict
   these value spaces are defined in Section 4.1.

6.2.5.  Software Tag Entity Role Values Registry

   This document establishes a new registry titled "Software Tag Entity
   Role Values".  This registry provides index values for use as entity-
   entry role item values in this document and entity role names for use
   in [SWID].

   [TO BE REMOVED: This registration should take place at the following
   location: https://www.iana.org/assignments/swid]

   This registry uses the registration procedures defined in
   Section 6.2.1 with the following associated ranges:

                   +=========+=========================+
                   | Range   | Registration Procedures |
                   +=========+=========================+
                   | 0-127   | Standards Action        |
                   +---------+-------------------------+
                   | 128-255 | Specification Required  |
                   +---------+-------------------------+

                        Table 12: CoSWID Entity Role
                          Registration Procedures

   Assignments consist of an integer Index value, a Role Name, and a
   reference to the defining specification.

   Initial registrations for the "Software Tag Entity Role Values"
   registry are provided below, which are derived from the textual
   entity role names defined in [SWID].














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               +=======+=================+=================+
               | Index | Role Name       | Specification   |
               +=======+=================+=================+
               | 0     | Reserved        |                 |
               +-------+-----------------+-----------------+
               | 1     | tagCreator      | See Section 4.2 |
               +-------+-----------------+-----------------+
               | 2     | softwareCreator | See Section 4.2 |
               +-------+-----------------+-----------------+
               | 3     | aggregator      | See Section 4.2 |
               +-------+-----------------+-----------------+
               | 4     | distributor     | See Section 4.2 |
               +-------+-----------------+-----------------+
               | 5     | licensor        | See Section 4.2 |
               +-------+-----------------+-----------------+
               | 6     | maintainer      | See Section 4.2 |
               +-------+-----------------+-----------------+
               | 7-255 | Unassigned      |                 |
               +-------+-----------------+-----------------+

                    Table 13: CoSWID Entity Role Initial
                               Registrations

   Registrations MUST conform to the expert review guidelines defined in
   Section 6.2.3.

6.2.6.  Software Tag Link Ownership Values Registry

   This document establishes a new registry titled "Software Tag Link
   Ownership Values".  This registry provides index values for use as
   link-entry ownership item values in this document and link ownership
   names for use in [SWID].

   [TO BE REMOVED: This registration should take place at the following
   location: https://www.iana.org/assignments/swid]

   This registry uses the registration procedures defined in
   Section 6.2.1 with the following associated ranges:













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                   +=========+=========================+
                   | Range   | Registration Procedures |
                   +=========+=========================+
                   | 0-127   | Standards Action        |
                   +---------+-------------------------+
                   | 128-255 | Specification Required  |
                   +---------+-------------------------+

                      Table 14: CoSWID Link Ownership
                          Registration Procedures

   Assignments consist of an integer Index value, an Ownership Type
   Name, and a reference to the defining specification.

   Initial registrations for the "Software Tag Link Ownership Values"
   registry are provided below, which are derived from the textual
   entity role names defined in [SWID].

             +=======+=====================+=================+
             | Index | Ownership Type Name | Definition      |
             +=======+=====================+=================+
             | 0     | Reserved            |                 |
             +-------+---------------------+-----------------+
             | 1     | abandon             | See Section 4.3 |
             +-------+---------------------+-----------------+
             | 2     | private             | See Section 4.3 |
             +-------+---------------------+-----------------+
             | 3     | shared              | See Section 4.3 |
             +-------+---------------------+-----------------+
             | 4-255 | Unassigned          |                 |
             +-------+---------------------+-----------------+

                   Table 15: CoSWID Link Ownership Inital
                               Registrations

   Registrations MUST conform to the expert review guidelines defined in
   Section 6.2.3.

6.2.7.  Software Tag Link Relationship Values Registry

   This document establishes a new registry titled "Software Tag Link
   Relationship Values".  This registry provides index values for use as
   link-entry rel item values in this document and link ownership names
   for use in [SWID].

   [TO BE REMOVED: This registration should take place at the following
   location: https://www.iana.org/assignments/swid]




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   This registry uses the registration procedures defined in
   Section 6.2.1 with the following associated ranges:

                 +=============+=========================+
                 | Range       | Registration Procedures |
                 +=============+=========================+
                 | 0-32767     | Standards Action        |
                 +-------------+-------------------------+
                 | 32768-65535 | Specification Required  |
                 +-------------+-------------------------+

                     Table 16: CoSWID Link Relationship
                          Registration Procedures

   Assignments consist of an integer Index value, the Relationship Type
   Name, and a reference to the defining specification.

   Initial registrations for the "Software Tag Link Relationship Values"
   registry are provided below, which are derived from the link
   relationship values defined in [SWID].































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          +==========+========================+=================+
          | Index    | Relationship Type Name | Specification   |
          +==========+========================+=================+
          | 0        | Reserved               |                 |
          +----------+------------------------+-----------------+
          | 1        | ancestor               | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 2        | component              | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 3        | feature                | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 4        | installationmedia      | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 5        | packageinstaller       | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 6        | parent                 | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 7        | patches                | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 8        | requires               | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 9        | see-also               | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 10       | supersedes             | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 11       | supplemental           | See Section 4.4 |
          +----------+------------------------+-----------------+
          | 12-65535 | Unassigned             |                 |
          +----------+------------------------+-----------------+

                 Table 17: CoSWID Link Relationship Initial
                               Registrations

   Registrations MUST conform to the expert review guidelines defined in
   Section 6.2.3.

   Designated experts MUST also ensure that a newly requested entry
   documents the URI schemes allowed to be used in an href associated
   with the link relationship and the expected resolution behavior of
   these URI schemes.  This will help to ensure that applications
   processing software tags are able to interoperate when resolving
   resources referenced by a link of a given type.









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6.2.8.  Software Tag Link Use Values Registry

   This document establishes a new registry titled "Software Tag Link
   Use Values".  This registry provides index values for use as link-
   entry use item values in this document and link use names for use in
   [SWID].

   [TO BE REMOVED: This registration should take place at the following
   location: https://www.iana.org/assignments/swid]

   This registry uses the registration procedures defined in
   Section 6.2.1 with the following associated ranges:

                   +=========+=========================+
                   | Range   | Registration Procedures |
                   +=========+=========================+
                   | 0-127   | Standards Action        |
                   +---------+-------------------------+
                   | 128-255 | Specification Required  |
                   +---------+-------------------------+

                         Table 18: CoSWID Link Use
                          Registration Procedures

   Assignments consist of an integer Index value, the Link Use Type
   Name, and a reference to the defining specification.

   Initial registrations for the "Software Tag Link Use Values" registry
   are provided below, which are derived from the link relationship
   values defined in [SWID].

             +=======+====================+=================+
             | Index | Link Use Type Name | Specification   |
             +=======+====================+=================+
             | 0     | Reserved           |                 |
             +-------+--------------------+-----------------+
             | 1     | optional           | See Section 4.5 |
             +-------+--------------------+-----------------+
             | 2     | required           | See Section 4.5 |
             +-------+--------------------+-----------------+
             | 3     | recommended        | See Section 4.5 |
             +-------+--------------------+-----------------+
             | 4-255 | Unassigned         |                 |
             +-------+--------------------+-----------------+

             Table 19: CoSWID Link Use Initial Registrations





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   Registrations MUST conform to the expert review guidelines defined in
   Section 6.2.3.

6.3.  swid+cbor Media Type Registration

   *_TODO: Per Section 5.1 of RFC6838, was a message sent to media-
   types@iana.org for preliminary review?  I didn't see it on that
   mailing list (did I miss it?).  Please kick that off._*

   IANA is requested to add the following to the IANA "Media Types"
   registry.

   Type name: application

   Subtype name: swid+cbor

   Required parameters: none

   Optional parameters: none

   Encoding considerations: Must be encoded as using [RFC7049].  See
   RFC-AAAA for details.

   Security considerations: See Section 9 of RFC-AAAA.

   Interoperability considerations: Applications MAY ignore any key
   value pairs that they do not understand.  This allows backwards
   compatible extensions to this specification.

   Published specification: RFC-AAAA

   Applications that use this media type: The type is used by software
   asset management systems, vulnerability assessment systems, and in
   applications that use remote integrity verification.

   Fragment identifier considerations: Fragment identification for
   application/swid+cbor is supported by using fragment identifiers as
   specified by RFC7049 Section 7.5.

   Additional information:

   Magic number(s): first five bytes in hex: da 53 57 49 44

   File extension(s): coswid

   Macintosh file type code(s): none





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   Macintosh Universal Type Identifier code: org.ietf.coswid conforms to
   public.data

   Person & email address to contact for further information: Henk
   Birkholz <henk.birkholz@sit.fraunhofer.de>

   Intended usage: COMMON

   Restrictions on usage: None

   Author: Henk Birkholz <henk.birkholz@sit.fraunhofer.de>

   Change controller: IESG

6.4.  CoAP Content-Format Registration

   IANA is requested to assign a CoAP Content-Format ID for the CoSWID
   media type in the "CoAP Content-Formats" sub-registry, from the "IETF
   Review or IESG Approval" space (256..999), within the "CoRE
   Parameters" registry [RFC7252]:

          +=======================+==========+======+===========+
          | Media type            | Encoding | ID   | Reference |
          +=======================+==========+======+===========+
          | application/swid+cbor | -        | TBD1 | RFC-AAAA  |
          +-----------------------+----------+------+-----------+

                     Table 20: CoAP Content-Format IDs

6.5.  CBOR Tag Registration

   IANA is requested to allocate a tag in the "CBOR Tags" registry,
   preferably with the specific value requested:

         +============+===========+=============================+
         | Tag        | Data Item | Semantics                   |
         +============+===========+=============================+
         | 1398229316 | map       | Concise Software Identifier |
         |            |           | (CoSWID) [RFC-AAAA]         |
         +------------+-----------+-----------------------------+

                        Table 21: CoSWID CBOR Tag









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6.6.  URI Scheme Registrations

   The ISO 19770-2:2015 SWID specification describes use of the "swid"
   and "swidpath" URI schemes, which are currently in use in
   implementations.  This document continues this use for CoSWID.  The
   following subsections provide registrations for these schemes in to
   ensure that a permanent registration exists for these schemes that is
   suitable for use in the SWID and CoSWID specifications.

   *_TODO: Per Step 3.2 of Section 7.2 of RFC7595, has this been sent to
   uri-review@ietf.org?  I didn't see it on that mailing list (did I
   miss it?).  Please kick that off._*

6.6.1.  "swid" URI Scheme Registration

   There is a need for a scheme name that can be used in URIs that point
   to a specific software tag by that tag's tag-id, such as the use of
   the link entry as described in Section 2.7) of this document.  Since
   this scheme is used in a standards track document and an ISO
   standard, this scheme needs to be used without fear of conflicts with
   current or future actual schemes.  The scheme "swid" is hereby
   registered as a 'permanent' scheme for that purpose.

   The "swid" scheme is specified as follows:

   Scheme name: swid

   Status: Permanent

   Applications/protocols that use this scheme name: See section
   Section 5.1.

   Contact: FIXME

   Change controller: FIXME

   References: FIXME

6.6.2.  "swidpath" URI Scheme Registration

   There is a need for a scheme name that can be used in URIs to
   identify a collection of specific software tags with data elements
   that match an XPath expression, such as the use of the link entry as
   described in Section 2.7) of this document.  Since this scheme is
   used in a standards track document and an ISO standard, this scheme
   needs to be used without fear of conflicts with current or future
   actual schemes.  The scheme "swidpath" is hereby registered as a
   'permanent' scheme for that purpose.



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   The "swidpath" scheme is specified as follows:

   Scheme name: swidpath

   Status: Permanent

   Applications/protocols that use this scheme name: See section
   Section 5.2.

   Contact: FIXME

   Change controller: FIXME

   References: FIXME

6.7.  CoSWID Model for use in SWIMA Registration

   The Software Inventory Message and Attributes (SWIMA) for PA-TNC
   specification [RFC8412] defines a standardized method for collecting
   an endpoint device's software inventory.  A CoSWID can provide
   evidence of software installation which can then be used and
   exchanged with SWIMA.  This registration adds a new entry to the IANA
   "Software Data Model Types" registry defined by [RFC8412] to support
   CoSWID use in SWIMA as follows:

   Pen: 0

   Integer: TBD2

   Name: Concise Software Identifier (CoSWID)

   Reference: RFC-AAAA

   Deriving Software Identifiers:

   A Software Identifier generated from a CoSWID tag is expressed as a
   concatenation of the form in [RFC5234] as follows:

   TAG_CREATOR_REGID "_" "_" UNIQUE_ID

   Where TAG_CREATOR_REGID is the reg-id item value of the tag's entity
   item having the role value of 1 (corresponding to "tag creator"), and
   the UNIQUE_ID is the same tag's tag-id item.  If the tag-id item's
   value is expressed as a 16 byte binary string, the UNIQUE_ID MUST be
   represented using the UUID string representation defined in [RFC4122]
   including the "urn:uuid:" prefix.





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   The TAG_CREATOR_REGID and the UNIQUE_ID are connected with a double
   underscore (_), without any other connecting character or whitespace.

7.  Signed CoSWID Tags

   SWID tags, as defined in the ISO-19770-2:2015 XML schema, can include
   cryptographic signatures to protect the integrity of the SWID tag.
   In general, tags are signed by the tag creator (typically, although
   not exclusively, the vendor of the software component that the SWID
   tag identifies).  Cryptographic signatures can make any modification
   of the tag detectable, which is especially important if the integrity
   of the tag is important, such as when the tag is providing reference
   integrity measurements for files.  The ISO-19770-2:2015 XML schema
   uses XML DSIG to support cryptographic signatures.

   Signing CoSWID tags follows the procedues defined in CBOR Object
   Signing and Encryption [RFC8152].  A CoSWID tg MUST be wrapped in a
   COSE Single Signer Data Object (COSE_Sign1) that contains a single
   signature and MUST be signed by the tag creator.  The following CDDL
   specification defines a restrictive subset of COSE header parameters
   that MUST be used in the protected header.

   COSE-Sign1-coswid<payload> = [
       protected: bstr .cbor protected-signed-coswid-header,
       unprotected: unprotected-signed-coswid-header,
       payload: bstr .cbor payload,
       signature: bstr,
   ]

   cose-label = int / tstr
   cose-values = any

   protected-signed-coswid-header = {
       1 => int,                      ; algorithm identifier
       3 => "application/swid+cbor",
       4 => bstr,                     ; key identifier
       * cose-label => cose-values,
   }

   unprotected-signed-coswid-header = {
       * cose-label => cose-values,
   }

   The COSE_Sign structure that allows for more than one signature to be
   applied to a CoSWID tag MAY be used.  The corresponding usage
   scenarios are domain-specific and require well-specified application
   guidance.




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   COSE-Sign-coswid<payload> = [
       protected: bstr .cbor protected-signed-coswid-header1,
       unprotected: unprotected-signed-coswid-header,
       payload: bstr .cbor payload,
       signature: [ * COSE_Signature ],
   ]

   protected-signed-coswid-header1 = {
       3 => "application/swid+cbor",
       * cose-label => cose-values,
   }

   protected-signature-coswid-header = {
       1 => int,                      ; algorithm identifier
       4 => bstr,                     ; key identifier
       * cose-label => cose-values,
   }

   unprotected-sign-coswid-header = {
       * cose-label => cose-values,
   }

   COSE_Signature =  [
       protected: bstr .cbor protected-signature-coswid-header,
       unprotected: unprotected-sign-coswid-header,
       signature : bstr
   ]

   Additionally, the COSE Header counter signature MAY be used as an
   attribute in the unprotected header map of the COSE envelope of a
   CoSWID.  The application of counter signing enables second parties to
   provide a signature on a signature allowing for a proof that a
   signature existed at a given time (i.e., a timestamp).

8.  Tagged CoSWID Tags

   This specification allows for tagged and untagged CBOR data items
   that are CoSWID tags.  Consecutively, the CBOR tag for CoSWID tags
   defined in Table 21 SHOULD be used in conjunction with CBOR data
   items that are a CoSWID tags.  Other CBOR tags MUST NOT be used with
   a CBOR data item that is a CoSWID tag.  If tagged, both signed and
   unsigned CoSWID tags MUST use the CoSWID CBOR tag.  In case a signed
   CoSWID is tagged, a CoSWID CBOR tag MUST be appended before the COSE
   envelope whether it is a COSE_Untagged_Message or a
   COSE_Tagged_Message.  In case an unsigned CoSWID is tagged, a CoSWID
   CBOR tag MUST be appended before the CBOR data item that is the
   CoSWID tag.




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   coswid = unsigned-coswid / signed-coswid
   unsigned-coswid = concise-swid-tag / tagged-coswid<concise-swid-tag>
   signed-coswid1 = signed-coswid-for<unsigned-coswid>
   signed-coswid = signed-coswid1 / tagged-coswid<signed-coswid1>

   tagged-coswid<T> = #6.1398229316(T)

   signed-coswid-for<payload> = #6.18(COSE-Sign1-coswid<payload>)
       / #6.98(COSE-Sign-coswid<payload>)

   While this specification allows for a tagged CoSWID tag to reside in
   a COSE envelope that is also tagged with a CoSWID CBOR tag, redundant
   use of tags SHOULD be avoided.

9.  Security Considerations

   The following security considerations for use of CoSWID tags focus
   on:

   *  ensuring the integrity and authenticity of a CoSWID tag

   *  the application of CoSWID tags to address security challenges
      related to unmanaged or unpatched software

   *  reducing the potential for unintended disclosure of a device's
      software load

   A tag is considered "authoritative" if the CoSWID tag was created by
   the software provider.  An authoritative CoSWID tag contains
   information about a software component provided by the maintainer of
   the software component, who is expected to be an expert in their own
   software.  Thus, authoritative CoSWID tags can be trusted to
   represent authoritative information about the software component.

   A signed CoSWID tag (see Section 7) whose signature has been
   validated can be relied upon to be unchanged since it was signed.  By
   contrast, the data contained in unsigned tags cannot be trusted to be
   unmodified.













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   When an authoritative tag is signed, the software provider can be
   authenticated as the originator of the signature.  A trustworthy
   association between the signature and the originator of the signature
   can be established via trust anchors.  A certification path between a
   trust anchor and a certificate including a pub-key enabling the
   validation of a tag signature can realize the assessment of
   trustworthiness of an authoritative tag.  Having a signed
   authoritative CoSWID tag can be useful when the information in the
   tag needs to be trusted, such as when the tag is being used to convey
   reference integrity measurements for software components.

   CoSWID tags are intended to contain public information about software
   components and, as such, the contents of a CoSWID tag does not need
   to be protected against unintended disclosure on an endpoint.

   CoSWID tags are intended to be easily discoverable by authorized
   applications and users on an endpoint in order to make it easy to
   determine the tagged software load.  Access to the collection of an
   endpoint's SWID tags needs to be appropriately controlled to
   authorized applications and users using an appropriate access control
   mechanism.

   CoSWID tags are designed to be easily added and removed from an
   endpoint along with the installation or removal of software
   components.  On endpoints where addition or removal of software
   components is tightly controlled, the addition or removal of SWID
   tags can be similarly controlled.  On more open systems, where many
   users can manage the software inventory, CoSWID tags can be easier to
   add or remove.  On such systems, it can be possible to add or remove
   CoSWID tags in a way that does not reflect the actual presence or
   absence of corresponding software components.  Similarly, not all
   software products automatically install CoSWID tags, so products can
   be present on an endpoint without providing a corresponding SWID tag.
   As such, any collection of CoSWID tags cannot automatically be
   assumed to represent either a complete or fully accurate
   representation of the software inventory of the endpoint.  However,
   especially on endpoint devices that more strictly control the ability
   to add or remove applications, CoSWID tags are an easy way to provide
   an preliminary understanding of that endpoint's software inventory.

   Any report of an endpoint's CoSWID tag collection provides
   information about the software inventory of that endpoint.  If such a
   report is exposed to an attacker, this can tell them which software
   products and versions thereof are present on the endpoint.  By
   examining this list, the attacker might learn of the presence of
   applications that are vulnerable to certain types of attacks.  As
   noted earlier, CoSWID tags are designed to be easily discoverable by
   an endpoint, but this does not present a significant risk since an



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   attacker would already need to have access to the endpoint to view
   that information.  However, when the endpoint transmits its software
   inventory to another party, or that inventory is stored on a server
   for later analysis, this can potentially expose this information to
   attackers who do not yet have access to the endpoint.  For this
   reason, it is important to protect the confidentiality of CoSWID tag
   information that has been collected from an endpoint in transit and
   at rest, not because those tags individually contain sensitive
   information, but because the collection of CoSWID tags and their
   association with an endpoint reveals information about that
   endpoint's attack surface.

   Finally, both the ISO-19770-2:2015 XML schema SWID definition and the
   CoSWID CDDL specification allow for the construction of "infinite"
   tags with link item loops or tags that contain malicious content with
   the intent of creating non-deterministic states during validation or
   processing of those tags.  While software providers are unlikely to
   do this, CoSWID tags can be created by any party and the CoSWID tags
   collected from an endpoint could contain a mixture of vendor and non-
   vendor created tags.  For this reason, a CoSWID tag might contain
   potentially malicious content.  Input sanitization and loop detection
   are two ways that implementations can address this concern.

10.  Acknowledgments

   This document draws heavily on the concepts defined in the ISO/IEC
   19770-2:2015 specification.  The authors of this document are
   grateful for the prior work of the 19770-2 contributors.

   We are also grateful to the careful reviews provided by ...

11.  Change Log

   [THIS SECTION TO BE REMOVED BY THE RFC EDITOR.]

   Changes from version 12 to version 14:

   *  Moved key identifier to protected COSE header

   *  Fixed index reference for hash

   *  Removed indirection of CDDL type definition for filesystem-item

   *  Fixed quantity of resource and process

   *  Updated resource-collection

   *  Renamed socket name in software-meta to be consistent in naming



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   *  Aligned excerpt examples in I-D text with full CDDL

   *  Fixed titels where title was referring to group instead of map

   *  Added missig date in SEMVER

   *  Fixed root cardinality for file and directory, etc.

   *  Transformed path-elements-entry from map to group for re-usability

   *  Scrubbed IANA Section

   *  Removed redundant supplemental rule

   *  Aligned discrepancy with ISO spec.

   *  Addressed comments on typos.

   *  Fixed kramdown nits and BCP reference.

   *  Addressed comments from WGLC reviewers.

   Changes in version 12:

   *  Addressed a bunch of minor editorial issues based on WGLC
      feedback.

   *  Added text about the use of UTF-8 in CoSWID.

   *  Adjusted tag-id to allow for a UUID to be provided as a bstr.

   *  Cleaned up descriptions of index ranges throughout the document,
      removing discussion of 8 bit, 16 bit, etc.

   *  Adjusted discussion of private use ranges to use negative integer
      values and to be more clear throughout the document.

   *  Added discussion around resolving overlapping value spaces for
      version schemes.

   *  Added a set of expert review guidelines for new IANA registries
      created by this document.

   *  Added new registrations for the "swid" and "swidpath" URI schemes,
      and for using CoSWID with SWIMA.

   Changes from version 03 to version 11:




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   *  Reduced representation complexity of the media-entry type and
      removed the Section describing the older data structure.

   *  Added more signature schemes from COSE

   *  Included a minimal required set of normative language

   *  Reordering of attribute name to integer label by priority
      according to semantics.

   *  Added an IANA registry for CoSWID items supporting future
      extension.

   *  Cleaned up IANA registrations, fixing some inconsistencies in the
      table labels.

   *  Added additional CDDL sockets for resource collection entries
      providing for additional extension points to address future SWID/
      CoSWID extensions.

   *  Updated Section on extension points to address new CDDL sockets
      and to reference the new IANA registry for items.

   *  Removed unused references and added new references to address
      placeholder comments.

   *  Added table with semantics for the link ownership item.

   *  Clarified language, made term use more consistent, fixed
      references, and replacing lowercase RFC2119 keywords.

   Changes from version 02 to version 03:

   *  Updated core CDDL including the CDDL design pattern according to
      RFC 8428.

   Changes from version 01 to version 02:

   *  Enforced a more strict separation between the core CoSWID
      definition and additional usage by moving content to corresponding
      appendices.

   *  Removed artifacts inherited from the reference schema provided by
      ISO (e.g.  NMTOKEN(S))

   *  Simplified the core data definition by removing group and type
      choices where possible




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   *  Minor reordering of map members

   *  Added a first extension point to address requested flexibility for
      extensions beyond the any-element

   Changes from version 00 to version 01:

   *  Ambiguity between evidence and payload eliminated by introducing
      explicit members (while still

   *  allowing for "empty" SWID tags)

   *  Added a relatively restrictive COSE envelope using cose_sign1 to
      define signed CoSWID (single signer only, at the moment)

   *  Added a definition how to encode hashes that can be stored in the
      any-member using existing IANA tables to reference hash-algorithms

   Changes since adopted as a WG I-D -00:

   *  Removed redundant any-attributes originating from the ISO-
      19770-2:2015 XML schema definition

   *  Fixed broken multi-map members

   *  Introduced a more restrictive item (any-element-map) to represent
      custom maps, increased restriction on types for the any-attribute,
      accordingly

   *  Fixed X.1520 reference

   *  Minor type changes of some attributes (e.g.  NMTOKENS)

   *  Added semantic differentiation of various name types (e,g. fs-
      name)

   Changes from version 06 to version 07:

   *  Added type choices/enumerations based on textual definitions in
      19770-2:2015

   *  Added value registry request

   *  Added media type registration request

   *  Added content format registration request

   *  Added CBOR tag registration request



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   *  Removed RIM appendix to be addressed in complementary draft

   *  Removed CWT appendix

   *  Flagged firmware resource collection appendix for revision

   *  Made use of terminology more consistent

   *  Better defined use of extension points in the CDDL

   *  Added definitions for indexed values

   *  Added IANA registry for Link use indexed values

   Changes from version 05 to version 06:

   *  Improved quantities

   *  Included proposals for implicit enumerations that were NMTOKENS

   *  Added extension points

   *  Improved exemplary firmware-resource extension

   Changes from version 04 to version 05:

   *  Clarified language around SWID and CoSWID to make more consistent
      use of these terms.

   *  Added language describing CBOR optimizations for single vs. arrays
      in the model front matter.

   *  Fixed a number of grammatical, spelling, and wording issues.

   *  Documented extension points that use CDDL sockets.

   *  Converted IANA registration tables to markdown tables, reserving
      the 0 value for use when a value is not known.

   *  Updated a number of references to their current versions.

   Changes from version 03 to version 04:

   *  Re-index label values in the CDDL.

   *  Added a Section describing the CoSWID model in detail.

   *  Created IANA registries for entity-role and version-scheme



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   Changes from version 02 to version 03:

   *  Updated CDDL to allow for a choice between a payload or evidence

   *  Re-index label values in the CDDL.

   *  Added item definitions

   *  Updated references for COSE, CBOR Web Token, and CDDL.

   Changes from version 01 to version 02:

   *  Added extensions for Firmware and CoSWID use as Reference
      Integrity Measurements (CoSWID RIM)

   *  Changes meta handling in CDDL from use of an explicit use of items
      to a more flexible unconstrained collection of items.

   *  Added Sections discussing use of COSE Signatures and CBOR Web
      Tokens

   Changes from version 00 to version 01:

   *  Added CWT usage for absolute SWID paths on a device

   *  Fixed cardinality of type-choices including arrays

   *  Included first iteration of firmware resource-collection

12.  References

12.1.  Normative References

   [BCP178]   Saint-Andre, P., Crocker, D., and M. Nottingham,
              "Deprecating the "X-" Prefix and Similar Constructs in
              Application Protocols", BCP 178, RFC 6648,
              DOI 10.17487/RFC6648, June 2012,
              <https://www.rfc-editor.org/rfc/rfc6648>.

   [BCP26]    Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/rfc/rfc8126>.

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




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   [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>.

   [RFC3629]  Yergeau, F., "UTF-8, a transformation format of ISO
              10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
              2003, <https://www.rfc-editor.org/rfc/rfc3629>.

   [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, DOI 10.17487/RFC3986, January 2005,
              <https://www.rfc-editor.org/rfc/rfc3986>.

   [RFC5198]  Klensin, J. and M. Padlipsky, "Unicode Format for Network
              Interchange", RFC 5198, DOI 10.17487/RFC5198, March 2008,
              <https://www.rfc-editor.org/rfc/rfc5198>.

   [RFC5234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", STD 68, RFC 5234,
              DOI 10.17487/RFC5234, January 2008,
              <https://www.rfc-editor.org/rfc/rfc5234>.

   [RFC5646]  Phillips, A., Ed. and M. Davis, Ed., "Tags for Identifying
              Languages", BCP 47, RFC 5646, DOI 10.17487/RFC5646,
              September 2009, <https://www.rfc-editor.org/rfc/rfc5646>.

   [RFC5892]  Faltstrom, P., Ed., "The Unicode Code Points and
              Internationalized Domain Names for Applications (IDNA)",
              RFC 5892, DOI 10.17487/RFC5892, August 2010,
              <https://www.rfc-editor.org/rfc/rfc5892>.

   [RFC7049]  Bormann, C. and P. Hoffman, "Concise Binary Object
              Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
              October 2013, <https://www.rfc-editor.org/rfc/rfc7049>.

   [RFC7252]  Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
              Application Protocol (CoAP)", RFC 7252,
              DOI 10.17487/RFC7252, June 2014,
              <https://www.rfc-editor.org/rfc/rfc7252>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/rfc/rfc8126>.






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   [RFC8152]  Schaad, J., "CBOR Object Signing and Encryption (COSE)",
              RFC 8152, DOI 10.17487/RFC8152, July 2017,
              <https://www.rfc-editor.org/rfc/rfc8152>.

   [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>.

   [RFC8288]  Nottingham, M., "Web Linking", RFC 8288,
              DOI 10.17487/RFC8288, October 2017,
              <https://www.rfc-editor.org/rfc/rfc8288>.

   [RFC8412]  Schmidt, C., Haynes, D., Coffin, C., Waltermire, D., and
              J. Fitzgerald-McKay, "Software Inventory Message and
              Attributes (SWIMA) for PA-TNC", RFC 8412,
              DOI 10.17487/RFC8412, July 2018,
              <https://www.rfc-editor.org/rfc/rfc8412>.

   [RFC8610]  Birkholz, H., Vigano, C., and C. Bormann, "Concise Data
              Definition Language (CDDL): A Notational Convention to
              Express Concise Binary Object Representation (CBOR) and
              JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610,
              June 2019, <https://www.rfc-editor.org/rfc/rfc8610>.

   [SAM]      "Information technology - Software asset management - Part
              5: Overview and vocabulary", ISO/IEC 19770-5:2015, 15
              November 2013.

   [SEMVER]   Preston-Werner, T., "Semantic Versioning 2.0.0",
              <https://semver.org/spec/v2.0.0.html>.

   [SWID]     "Information technology - Software asset management - Part
              2: Software identification tag", ISO/IEC 19770-2:2015, 1
              October 2015.

   [UNSPSC]   "United Nations Standard Products and Services Code", 26
              October 2020, <https://www.unspsc.org/>.

   [W3C.REC-css3-mediaqueries-20120619]
              Rivoal, F., "Media Queries", World Wide Web Consortium
              Recommendation REC-css3-mediaqueries-20120619, 19 June
              2012, <https://www.w3.org/TR/2012/REC-css3-mediaqueries-
              20120619>.








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Internet-Draft                   CoSWID                    February 2021


   [W3C.REC-xmlschema-2-20041028]
              Biron, P. and A. Malhotra, "XML Schema Part 2: Datatypes
              Second Edition", World Wide Web Consortium Recommendation
              REC-xmlschema-2-20041028, 28 October 2004,
              <https://www.w3.org/TR/2004/REC-xmlschema-2-20041028>.

   [W3C.REC-xpath20-20101214]
              Berglund, A., Boag, S., Chamberlin, D., Fernandez, M.,
              Kay, M., Robie, J., and J. Simeon, "XML Path Language
              (XPath) 2.0 (Second Edition)", World Wide Web Consortium
              Recommendation REC-xpath20-20101214, 14 December 2010,
              <https://www.w3.org/TR/2010/REC-xpath20-20101214>.

   [X.1520]   "Recommendation ITU-T X.1520 (2014), Common
              vulnerabilities and exposures", 20 April 2011.

12.2.  Informative References

   [CamelCase]
              "UpperCamelCase", 29 August 2014,
              <http://wiki.c2.com/?CamelCase>.

   [I-D.ietf-rats-architecture]
              Birkholz, H., Thaler, D., Richardson, M., Smith, N., and
              W. Pan, "Remote Attestation Procedures Architecture", Work
              in Progress, Internet-Draft, draft-ietf-rats-architecture-
              10, 9 February 2021, <https://tools.ietf.org/html/draft-
              ietf-rats-architecture-10>.

   [KebabCase]
              "KebabCase", 18 December 2014,
              <http://wiki.c2.com/?KebabCase>.

   [RFC3444]  Pras, A. and J. Schoenwaelder, "On the Difference between
              Information Models and Data Models", RFC 3444,
              DOI 10.17487/RFC3444, January 2003,
              <https://www.rfc-editor.org/rfc/rfc3444>.

   [RFC4122]  Leach, P., Mealling, M., and R. Salz, "A Universally
              Unique IDentifier (UUID) URN Namespace", RFC 4122,
              DOI 10.17487/RFC4122, July 2005,
              <https://www.rfc-editor.org/rfc/rfc4122>.

   [RFC8322]  Field, J., Banghart, S., and D. Waltermire, "Resource-
              Oriented Lightweight Information Exchange (ROLIE)",
              RFC 8322, DOI 10.17487/RFC8322, February 2018,
              <https://www.rfc-editor.org/rfc/rfc8322>.




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   [RFC8520]  Lear, E., Droms, R., and D. Romascanu, "Manufacturer Usage
              Description Specification", RFC 8520,
              DOI 10.17487/RFC8520, March 2019,
              <https://www.rfc-editor.org/rfc/rfc8520>.

   [SWID-GUIDANCE]
              Waltermire, D., Cheikes, B.A., Feldman, L., and G. Witte,
              "Guidelines for the Creation of Interoperable Software
              Identification (SWID) Tags", NISTIR 8060, April 2016,
              <https://doi.org/10.6028/NIST.IR.8060>.

Authors' Addresses

   Henk Birkholz
   Fraunhofer SIT
   Rheinstrasse 75
   64295 Darmstadt
   Germany

   Email: henk.birkholz@sit.fraunhofer.de


   Jessica Fitzgerald-McKay
   National Security Agency
   9800 Savage Road
   Ft. Meade, Maryland
   United States of America

   Email: jmfitz2@cyber.nsa.gov


   Charles Schmidt
   The MITRE Corporation
   202 Burlington Road
   Bedford, Massachusetts 01730
   United States of America

   Email: cmschmidt@mitre.org


   David Waltermire
   National Institute of Standards and Technology
   100 Bureau Drive
   Gaithersburg, Maryland 20877
   United States of America

   Email: david.waltermire@nist.gov




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