Concise Software IdentifiersFraunhofer SITRheinstrasse 75Darmstadt64295Germanyhenk.birkholz@sit.fraunhofer.deDepartment of Defense9800 Savage RoadFt. MeadeMarylandUSAjmfitz2@nsa.govThe MITRE Corporation202 Burlington RoadBedfordMaryland01730USAcmschmidt@mitre.orgNational Institute of Standards and Technology100 Bureau DriveGaithersburgMaryland20877USAdavid.waltermire@nist.gov
Security
SACM Working GroupInternet-DraftThis document defines a concise representation of ISO/IEC 19770-2:2015 Software Identification (SWID) tags
that are interoperable with the XML schema definition of ISO/IEC 19770-2:2015 and augmented for
application in Constrained-Node Networks. Next to the inherent capability of SWID tags to express
arbitrary context information, Concise SWID (CoSWID) tags support the definition of additional semantics via
well-defined data definitions incorporated by extension points.SWID tags have several use-applications including but not limited to:Software Inventory Management, a part of the Software Asset Management
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 .Remote Attestation, which requires a link between reference integrity
measurements (RIM) and security logs of measured software components
.SWID tags, as defined in ISO-19770-2:2015 , provide a standardized
XML-based record format that identifies and describes a specific release of a
software component. 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.While there are very few required fields in SWID tags, there are many optional
fields that support different use scenarios. While a
SWID tag consisting of only required fields might be a few hundred bytes in
size, 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 use-applications 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. This reduction is enabled
through the use of CBOR, which maps human-readable labels of that content to
more concise integer labels (indices). 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.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 product’s SWID tag is also
installed. Likewise, when the product 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 correspondingsponding SWID tags
for these components on that endpoint. CoSWIDs share the same lifecycle requirements
as a SWID tag.The following is an excerpt (with some modifications and reordering) from NIST Interagency Report (NISTIR) 8060: Guidelines for the Creation of Interoperable SWID Tags , which describes the tag types used within the lifecycle defined in ISO-19770-2:2015.The SWID specification defines four types of SWID tags: primary, patch, corpus, and supplemental.Primary Tag - A SWID or CoSWID tag that identifies and describes a software component is installed on a computing device.Patch Tag - A SWID or CoSWID tag that identifies and describes an installed patch which has made incremental changes to a software component installed on a computing device.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.Supplemental Tag - A SWID or CoSWID tag that allows additional information to be associated with a referenced SWID tag. This helps to ensure that SWID Primary and Patch Tags provided by a software provider are not modified by software management tools, while allowing these tools to provide their own software metadata.Corpus, primary, and patch tags have similar functions in that they describe the existence and/or presence of different types of software (e.g., software installers, software installations, software patches), and, potentially, different states of software components. In contrast, supplemental tags furnish additional information not contained in corpus, primary, or 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. illustrates the steps in the software lifecycle and the relationships among those lifecycle events supported by the four types of SWID and CoSWID tags, 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).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 may also be installed during software installation to provide information about software fixes deployed along with the base software installation.Software Patching. When a new patch is applied to the software component, a new patch tag is provided, 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.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.Note: While not fully 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.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.This document defines the CoSWID format, a more concise representation of SWID information in the Concise
Binary Object Representation (CBOR) . This is described via the Concise
Data Definition Language (CDDL) . The resulting CoSWID data
definition is interoperable with the XML schema definition of ISO-19770-2:2015
. The vocabulary, i.e., the CDDL names of the types and members used in
the CoSWID data definition, are mapped to more concise labels represented as
small integer values. The names used in the CDDL data definition and the mapping to
the CBOR representation using integer labels is based on the vocabulary of the
XML attribute and element names defined in ISO/IEC 19770-2:2015.The corresponding CoSWID data definition includes two kinds of augmentation.The explicit definition of types for attributes that are typically stored in
the “any attribute” of an ISO-19770-2:2015 in XML representation. These are
covered in and of this document.The inclusion of extension points in the CoSWID data definition that allow for
additional uses of CoSWID tags that go beyond the original scope of
ISO-19770-2:2015 tags. These are covered in and .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 RFC
2119, BCP 14 .The following is a CDDL representation for a CoSWID tag. This CDDL represetation is intended to be parallel to the XML schema definition in the ISO/IEC 19770-2:2015 specification, allowing both SWID and CoSWID tags to represent a common set of SWID information and to support all SWID tag use
cases. To achieve this end, the CDDL representation includes every SWID tag field and attribute. The CamelCase notation used in the XML schema definition is changed to a hyphen-separated
notation (e.g. ResourceCollection is named resource-collection in the CoSWID data definition).
This deviation from the original notation used in the XML representation reduces ambiguity when referencing
certain attributes in corresponding textual descriptions. An attribute referred by its name in CamelCase
notation explicitly relates to XML SWID tags, an attribute referred by its name in
hyphen-separated notation explicitly relates to CoSWID tags. This approach simplifies the
composition of further work that reference both XML SWID and CoSWID documents.Human-readable names of members in the CDDL data definition are mapped to integer indices via a block of rules at the bottom
of the definition. The 67 character strings of the SWID vocabulary that would have to be
stored or transported in full if using the original vocabulary are replaced.In CBOR, an array is encoded using bytes that identify the array, and the array’s length or stop point (see ). To make items that support 1 or more values, the following CDDL notion is used.The CDDL above allows for a more effecient CBOR encoding of the data when a single value is used by avoiding the need to first encode the array. An array is used for two or more values. This modeling pattern is used frequently in the CoSWID CDDL data definition in such cases.The following subsections describe the different parts of the CoSWID model.The CDDL for the main concise-software-identity object is as follows:The following describes each child item of the concise-software-identity object model.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 .tag-id (label 0): An textual identifier uniquely referencing a (composite) software component. The tag
identifier MUST be globally unique. There are no strict guidelines on
how this identifier is structured, but examples include a 16 byte GUID (e.g.
class 4 UUID) .tag-version (label 12): An integer value that indicates if a specific release of a software component has more than
one tag that can represent that specific release. 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 item is used when a
CoSWID tag producer creates and releases an incorrect tag that they subsequently
want to fix, but no underlying changes have been made to the product the CoSWID tag
represents. This could happen if, for example, a patch is distributed that has a
link reference that does not cover all the various software releases it can
patch. A newer CoSWID tag for that patch can be generated and the tag-version
value incremented to indicate that the data is updated.corpus (label 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 (label 9): A boolean value that indicates if the tag identifies and describes an installed patch which has made incremental changes to a software component installed on a computing device. Typically, an installed patch has made a set of file modifications to pre-installed software, and does not alter the version number or the descriptive metadata of an installed software
component. If a CoSWID tag is for a patch, it MUST contain the patch item
and its value MUST be set to “true”. If not provided the default value MUST be considered “false”.supplemental (label 11): A boolean value that indicates if the tag is providing additional information to be associated with another referenced SWID or CoSWID tag. Tags using this item help to ensure that primary and patch tags provided by a software provider are not modified by software management tools, while allowing these tools to provide their own software metadata for a software component. If a CoSWID tag is a supplemntal tag, it MUST contain the supplemental item and its value MUST be set to “true”. If not provided the default value MUST be considered “false”.swid-name (label 1): This textual item provides the software component name as it would typically be
referenced. For example, what would be seen in the add/remove software dialog in an operating system,
or what is specified as the name of a packaged software component
or a patch identifier name.software-version (label 13): A textual value representing the specific underlying release or development version of the software component.version-scheme (label 14): An 8-bit integer or textual value representing the versioning scheme used for the software-version item. If an integer value is used it MUST be a value from the registry (see section or a value in the private use range: 32768-65,535.media (label 10): This text value is a hint to the tag consumer to understand what this tag
applies to. This item represents a
query as defined by the W3C Media Queries Recommendation (see
http://www.w3.org/TR/css3-mediaqueries/). A hint to the consumer of the link to
what the target item is applicable for.software-meta-entry (label 5): An open-ended collection of key/value data related to this CoSWID.
A number of predefined attributes can be used within this item providing for
common usage and semantics across the industry. The data definition of this entry allows for any additional
attribute to be included, though it is recommended that industry
norms for new attributes are defined and followed to the degree possible. Described in .entity-entry (label 2): Specifies the organizations related to the software component referenced by this
CoSWID tag. Described in .link-entry (label 4): Provides a means to establish a relationship arc between the tag and another item. A link can be used to establish relationships between tags and to reference other resources that are related to the
CoSWID tag, e.g.
vulnerability database associations, ROLIE feeds, MUD files, software download location, etc).
This is modeled after the HTML “link” element. Described in .payload-entry (label 6): The items that may be installed on a system entity when the software component
is installed. Note that payload may be a superset of the items installed and -
depending on optimization mechanisms in respect to that system entity - may or
may not include every item that could be created or executed on the
corresponding system entitiy when software components are installed.
In general, payload will be used to indicate the files that may be installed
with a software component. Therefore payload will often be a superset of those
files (i.e. if a particular optional sub-component is not installed, the files
associated with that software component may be included in payload, but not
installed in the system entity). Described in .evidence-entry (label 3): This item is used to provide results from a scan of a system where software that
does not have a CoSWID tag is discovered. This information is not provided by
the software-creator, and is instead created when a system is being scanned and
the evidence for why software is believed to be installed on the device is
provided in the evidence item. Described in .any-element-entry (label 7): A default map that can contain arbitrary map members and even nested maps (which
would also be any-elements). In essence, the any-element allows items not
defined in this CDDL data definition to be included in a Concise Software
Identifier. Described in .The operational model for SWID and CoSWID tags introduced in . The following rules can be used to determine the type of a CoSWID tag.Corpus Tag: A CoSWID tag MUST be considered a corpus tag if the corpus item is “true”.Primary Tag: A CoSWID tag MUST be considered a primary tag if the corpus, patch, and supplemental items are “false”.Patch Tag: A CoSWID tag MUST be considered a patch tag if the patch item is “true” and the corpus item is “false”.Supplemental Tag: A CoSWID tag MUST be considered a supplemental tag if the supplemental item is set to “true”.A tag that does not match one of the above rules MUST be considered an invalid, unsupported tag type.If a patch modifies the version number or the descriptive metadata of the software, then a new tag representing these details SHOULD be installed, and the old tag SHOULD be removed.Only one of the corpus, patch, and supplemental items MUST be set to “true”, or all of the corpus, patch, and supplemental items MUST be set to “false” or be omitted.If the patch item is set to “true”, the the tag SHOULD contain at least one link with the rel(ation) item value of “patches” and an href item specifying an association with the software that was patched.If the supplemental item is set to “true”, the the tag SHOULD contain at least one link with the rel(ation) item value of “supplements” 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.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 is as follows:The following describes each child item of this object.lang (index 15): A language tag or corresponding IANA index integer that
conforms with IANA Language Subtag Registry . any-attribute: This sub-group provides a means to include arbitrary information
via label (key) item value pairs where both keys and values can be
either a single integer or text string, or an array of integers or text strings.The CDDL for the any-element-entry object is as follows:The following describes each child item of this object.global-attributes: The global-attributes group described in .label: a single or multiple The CDDL for the entity object is as follows:The following describes each child item of this object.global-attributes: The global-attributes group described in .entity-name (index 32): The text-string name of the organization claiming a particular role in the CoSWID
tag.reg-id (index 32): The registration id is intended to uniquely identify a naming authority in a
given scope (e.g. global, organization, vendor, customer, administrative domain,
etc.) that is implied by the referenced naming authority. The value of an
registration ID MUST be a RFC 3986 URI. The scope SHOULD be the scope of an
organization. In a given scope, the registration id MUST be used consistently.role (index 33): The relationship(s) between this organization and this tag. The role of tag creator
is required for every CoSWID tag. The role of an entity may include any role
value, but the pre-defined roles include: “aggregator”, “distributor”,
“licensor”, “software-creator”, and “tag-creator”. These pre-defined role index and text values are defined in . Use of index values instead of text for these pre-defined roles allows a CoSWID to be more concise.thumbprint (index 34): The value of the thmbprint item provides an integer-based hash algorithm identifier (hash-alg-id) and a byte string string value (hash-value) that contains the corresponding hash value (i.e. the
thumbprint) of the signing entities certificate(s). If the hash-alg-id is not known, then the integer value “0” MUST be used. This ensures parity between the SWID tag specification , which does not allow an algorithm to be identified for this field. See for more details on the use of the hash-entry data structure.extended-data (index 30): An open-ended collection of elements that can be used to attach arbitrary
metadata to an entity item.The CDDL for the link object is as follows:The following describes each child item of this object.global-attributes: The global-attributes group described in .artifact (index: 37): For installation media (rel=”installation-media”), this item value indicates the path of the installer executable or script that can be run to launch the referenced installation. Items with the same artifact name should be considered mirrors of each other, allowing the installation media to be downloaded from any of the described sources.href (index 38): The link to the item being referenced. The “href” item’s value can point to several different things, and can be any of the following:
If no URI scheme is provided, then the URI is to be interpreted as being relative to the URI of the CoSWID tag. For example, “./folder/supplemental.coswid”.a physical resource location with any system-acceptable URI scheme (e.g., file:// http:// https:// ftp://)a URI with “coswid:” as the scheme, which refers to another CoSWID by tag-id. This
URI would need to be resolved in the context of the system by software
that can lookup other CoSWID tags. For example, “coswid: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 CoSIWD via an
XPATH query. This URI would need to be resolved in the context of the system
entity via dedicated software components that can lookup other CoSWID tags and
select the appropriate tag based on an XPATH query. Examples include:swidpath://SoftwareIdentity[Entity/@regid=’http://contoso.com’] would retrieve all CoSWID tags that include an entity where the regid is “Contoso” or swidpath://SoftwareIdentity[Meta/@persistentId=’b0c55172-38e9-4e36-be86-92206ad8eddb’] would match CoSWID tags with the persistent-id value “b0c55172-38e9-4e36-be86-92206ad8eddb”.See XPATH query standard : http://www.w3.org/TR/xpath20/ media (index 10): See media defined in .ownership (index 39): Determines the relative strength of ownership of the software components. Valid
enumerations are: abandon, private, sharedrel (index 40): The relationship between this CoSWID and the target file. Relationships can be
identified by referencing the IANA registration library: https://www.iana.org/assignments/link-relations/link-relations.xhtml.media-type (index 41): The IANA MediaType for the target file; this provides the consumer with
intelligence of what to expect. See
http://www.iana.org/assignments/media-types/media-types.xhtml for more details
on link type.use (index 42): Determines if the target software is a hard requirement or not. Valid
enumerations are: required, recommended, optional.The CDDL for the software-meta object is as follows:The following describes each child item of this object.global-attributes: The global-attributes group described in .activation-status (index 43): Identification of the activation status of this software title (e.g. Trial,
Serialized, Licensed, Unlicensed, etc). Typically, this is used in supplemental
tags.channel-type (index 44): Provides information on which channel this particular software was targeted for
(e.g. Volume, Retail, OEM, Academic, etc). Typically used in supplemental tags.colloquial-version (index 45): The informal or colloquial version of the product (i.e. 2013). Note that this
version may be the same through multiple releases of a software component where
the version specified in entity is much more specific and will change for each
software release.
Note that this representation of version is typically used to identify a group
of specific software releases that are part of the same release/support
infrastructure (i.e. Fabrikam Office 2013). This version is used for string
comparisons only and is not compared to be an earlier or later
release (that is done via the entity version). description (index 46): A longer, detailed description of the software. This description can be
multiple sentences (differentiated from summary, which is a very short,
one-sentence description).edition (index 47): The variation of the product (Extended, Enterprise, Professional, Standard etc).entitlement-data-required (index 48): An indicator to determine if there should be accompanying proof of entitlement
when a software license reconciliation is completed.entitlement-key (index 49): A vendor-specific textual key that can be used to reconcile the validity of an
entitlement. (e.g. serial number, product or license key).generator (index 50): The name of the software tool that created a CoSWID tag. This item is typically
used if tags are created on the fly or via a catalog-based analysis for data
found on a computing device.persistent-id (index 51): A GUID used to represent products installed where the products are related, but may be different versions.product (index 52): The base name of the product (e.g. ).product-family (index 53): The overall product family this software belongs to. Product family is not used
to identify that a product is part of a suite, but is instead used when a set of
products that are all related may be installed on multiple different devices.
For example, an enterprise backup system may consist of a backup services,
multiple different backup services that support mail services, databases and ERP
systems, as well as individual software components that backup client system
entities. In such an usage scenario, all software components that are part of
the backup system would have the same product-family name so they can be grouped
together in respect to reporting systems.revision (index 54): The informal or colloquial representation of the sub-version of the given
product (ie, SP1, R2, RC1, Beta 2, etc). Note that the version
will provide very exact version details,
the revision is intended for use in environments where reporting on the informal
or colloquial representation of the software is important (for example, if for a
certain business process, an organization recognizes that it must have, for
example “ServicePack 1” or later of a specific product installed on all devices,
they can use the revision data value to quickly identify any devices that do not
meet this requirement).
Depending on how a software organizations distributes revisions, this value
could be specified in a primary (if distributed as an upgrade) or supplemental
(if distributed as a patch) CoSWID tag.summary (index 55): A short (one-sentence) description of the software.unspsc-code (index 56): An 8 digit code that provides UNSPSC classification of the software component this SWID tag identifies. For more information see, http://www.unspsc.org/.unspsc-version (index 57): The version of the UNSPSC code used to define the UNSPSC code value. For more information see, http://www.unspsc.org/.CoSWID add explicit support for the representation of hash entries using algorithms that are
registered at the Named Information Hash Algorithm Registry via the hash-entry member (label 58).The number used as a value for hash-alg-id MUST refer an ID in the Named Information Hash Algorithm
Registry; other hash algorithms MUST NOT be used. The hash-value MUST represent the raw hash value of the hashed resource generated using the hash algorithm indicated by the hash-alg-id.A list of items both used in evidence (discovered by an inventory process) and
payload (installed in a system entity) content of a CoSWID tag document to
structure and differentiate the content of specific CoSWID tag types. Potential
content includes directories, files, processes, resources or firmwares.The CDDL for the resource-collection group is as follows:The following describes each child item or group for these groups.filesystem-item: A list of items both used in representing the nodes of a file-system hierarchy,
i.e. directory items that allow one or more directories to be defined in the
file structure, and file items that allow one or more files to be specified for
a given location.global-attributes: The global-attributes group described in .directory-entry (index 16): A directory item allows one or more directories to be defined in the file
structure.file-entry (index 17): A file element that allows one or more files to be specified for a given
location.process-entry (index 18): Provides process (software component in execution) information for data that
will show up in a devices process table.resource-entry (index 19): A set of items that can be used to provide arbitrary resource information about
an application installed on a system entity, or evidence collected from a
system entity.size (index 20): The file size in bytes of the file.file-version (index 21): The version of the file.key (index 22): Files that are considered important or required for the use of a software
component. Typical key files would be those which, if not available on a system
entity, would cause the software component not to execute or function properly.
Key files will typically be used to validate that a software component
referenced by the CoSWID tag document is actually installed on a specific system
entity.location (index 23): The directory or location where a file was found or can expected to be located.
This text-string is intended to include the filename itself. This SHOULD be the
relative path from the location represented by the root item.fs-name (index 24): The file name or directory name without any path characters.root (index 25): A system-specific root folder that the location item is an offset from. If this
is not specified the assumption is the root is the same folder as the location
of the CoSWID tag. The text-string value represents a path expression relative
to the CoSWID tag document location in the (composite) file-system hierarchy.path-elements (index 26): Provides the ability to apply a directory structure to the path expressions for
files defined in a payload or evidence item.process-name (index 27): The process name as it will be found in the system entity’s process table.pid (index 28): The process ID for the process in execution that can be included in the process
item as part of an evidence tag.type (index 29): The type of resource represented via a text-string (typically, registry-key,
port or root-uri).The CDDL for the payload object is as follows:The following describes each child item of this object.global-attributes: The global-attributes group described in .resource-collection: The resource-collection group described in .$$payload-extension: This CDDL socket (see section 3.9) can be used to extend the payload model, allowing well-formed extensions to be defined in additional CDDL descriptions.The CDDL for the evidence object is as follows:The following describes each child item of this object.global-attributes: The global-attributes group described in .resource-collection: The resource-collection group described in .date (index 35): The date and time evidence represented by an evidence item was gathered.device-id (index 36): A text-string identifier for a device evidence was gathered from.$$evidence-extension: This CDDL socket (see section 3.9) can be used to extend the evidence model, allowing well-formed extensions to be defined in additional CDDL descriptions.In order to create a valid CoSWID document the structure of the corresponding CBOR message MUST
adhere to the following CDDL data definition.The following are an initial set of values for use in the version-scheme item for the version schemes defined in the ISO/IEC 19770-2:2015 specification. Index value in parens indicates the index value to use in the version-scheme item.multipartnumeric (index 1): 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)multipartnumeric+suffix (index 2): Numbers separated by dots, where the numbers are interpreted as integers with an additional string suffix(e.g., 1.2.3a)alphanumeric (index 3): Strictly a string, sorting is done alphanumericallydecimal (index 4): A floating point number (e.g., 1.25 is less than 1.3)semver (index 16384): Follows the specificationThe values above are registered in the “SWID/CoSWID Version Schema Values” registry defined in section . Additional valid values will likely be registered over time in this registry.The following table indicates the index value to use for the entity roles defined in the ISO/IEC 19770-2:2015 specification.IndexRole Name0Reserved1tagCreator2softwareCreator3aggregator4distributor5licensorThe values above are registered in the “SWID/CoSWID Entity Role Values” registry defined in section . Additional valid values will likely be registered over time. Additionally, the index values 226 through 255 have been reserved for private use.This document will include requests to IANA:Integer indices for SWID content attributes and information elements.Content-Type for CoAP to be used in COSE.This document has a number of IANA considerations, as described in
the following subsections.This document uses unsigned 16-bit index values to version-scheme item values. The
initial set of version-scheme values are derived from the textual version scheme names
defined in the ISO/IEC 19770-2:2015 specification .This document defines a new a new registry entitled
“SWID/CoSWID Version Schema Values”. Future registrations for this
registry are to be made based on as follows:RangeRegistration Procedures0-16383Standards Action16384-32767Specification Required32768-65535Reserved for Private UseInitial registrations for the SWID/CoSWID Version Schema Values registry
are provided below.IndexRole NameSpecification0Reserved1multipartnumericSee 2multipartnumeric+suffixSee 3alphanumericSee 4decimalSee 5-16383Unassigned16384semver16385-32767Unassigned32768-65535Reserved for Private UseThis document uses unsigned 8-bit index values to represent entity-role values. The
initial set of Entity roles are derived from the textual role names
defined in the ISO/IEC 19770-2:2015 specification .This document defines a new a new registry entitled
“SWID/CoSWID Entity Role Values”. Future registrations for this
registry are to be made based on as follows:RangeRegistration Procedures0-31Standards Action32-127Specification Required128-255Reserved for Private UseInitial registrations for the SWID/CoSWID Entity Role Values registry
are provided below.IndexRole NameSpecification0Reserved1tagCreatorSee 2softwareCreatorSee 3aggregatorSee 4distributorSee 5licensorSee 6-49Unassigned50-225Unassigned225-255Reserved for Private UseSWID and CoSWID tags contain public information about software components and, as
such, do not need to be protected against disclosure on an endpoint.
Similarly, SWID tags are intended to be easily discoverable by
applications and users on an endpoint in order to make it easy to
identify and collect all of an endpoint’s SWID tags. As such, any
security considerations regarding SWID tags focus on the application
of SWID tags to address security challenges, and the possible
disclosure of the results of those applications.A signed SWID tag whose signature has been validated can be relied upon to be
unchanged since it was signed. If the SWID tag was created by the
software provider, is signed, and the software provider can be authenticated as the originator of the signature, then the tag can be considered authoritative.
In this way, an authoritative SWID tag contains information about a software product provided by the maintainer of the product, who is expected to be an expert in their own product. Thus, authoritative SWID tags can be trusted to represent authoritative information about the software product. Having an authoritative SWID 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. By contrast, the data contained in unsigned
tags cannot be trusted to be unmodified.SWID 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, SWID tags may be easier to add or
remove. On such systems, it may be possible to add or remove SWID
tags in a way that does not reflect the actual presence or absence of
corresponding software components. Similarly, not all software
products automatically install SWID tags, so products may be present
on an endpoint without providing a corresponding SWID tag. As such,
any collection of SWID tags cannot automatically be assumed to
represent either a complete or fully accurate representation of the
software inventory of the endpoint. However, especially on devices
that more strictly control the ability to add or remove applications,
SWID tags are an easy way to provide an preliminary understanding of
that endpoint’s software inventory.Any report of an endpoint’s SWID 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, SWID tags are designed to be easily discoverable by an
endpoint, but this does not present a significant risk since an
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. As such, it is
important to protect the confidentiality of SWID tag information that
has been collected from an endpoint, not because those tags
individually contain sensitive information, but because the
collection of SWID tags and their association with an endpoint
reveals information about that endpoint’s attack surface.Finally, both the ISO-19770-2:2015 XML schema definition and the
Concise SWID data definition allow for the construction of “infinite”
SWID tags or SWID tags that contain malicious content with the intent
if creating non-deterministic states during validation or processing of SWID tags. While software
product vendors are unlikely to do this, SWID tags can be created by any party and the SWID tags
collected from an endpoint could contain a mixture of vendor and non-vendor created tags. For this
reason, tools that consume SWID tags ought to treat the tag contents as potentially malicious and
should employ input sanitizing on the tags they ingest.Changes from version 04 to version 05:Clarified language around SWID and CoSWID to make more consistant use of these terms.Added language describing CBOR optimizations for single vs. arrays in the model front matter.Fixed a number of gramatical, 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-schemeChanges from version 02 to version 03:Updated CDDL to allow for a choice between a payload or evidenceRe-index label values in the CDDL.Added item definitionsUpdated 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 TokensChanges from version 00 to version 01:Added CWT usage for absolute SWID paths on a deviceFixed cardinality of type-choices including arraysIncluded first iteration of firmware resource-collectionChanges since adopted as a WG I-D -00:Removed redundant any-attributes originating from the ISO-19770-2:2015 XML schema definitionFixed broken multi-map membersIntroduced a more restrictive item (any-element-map) to represent custom maps, increased restriction on types for the any-attribute, accordinglyFixed X.1520 referenceMinor type changes of some attributes (e.g. NMTOKENS)Added semantic differentiation of various name types (e,g. fs-name)Changes from version 00 to version 01:Ambiguity between evidence and payload eliminated by introducing explicit members (while stillallowing 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-algorithmsChanges 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 possibleMinor reordering of map membersAdded a first extension point to address requested flexibility for extensions beyond the
any-elementKey words for use in RFCs to Indicate Requirement LevelsIn many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.Using Cryptographic Message Syntax (CMS) to Protect Firmware PackagesThis document describes the use of the Cryptographic Message Syntax (CMS) to protect firmware packages, which provide object code for one or more hardware module components. CMS is specified in RFC 3852. A digital signature is used to protect the firmware package from undetected modification and to provide data origin authentication. Encryption is optionally used to protect the firmware package from disclosure, and compression is optionally used to reduce the size of the protected firmware package. A firmware package loading receipt can optionally be generated to acknowledge the successful loading of a firmware package. Similarly, a firmware package load error report can optionally be generated to convey the failure to load a firmware package. [STANDARDS-TRACK]Tags for Identifying LanguagesThis document describes the structure, content, construction, and semantics of language tags for use in cases where it is desirable to indicate the language used in an information object. It also describes how to register values for use in language tags and the creation of user-defined extensions for private interchange. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.Concise Binary Object Representation (CBOR)The Concise Binary Object Representation (CBOR) is a data format whose design goals include the possibility of extremely small code size, fairly small message size, and extensibility without the need for version negotiation. These design goals make it different from earlier binary serializations such as ASN.1 and MessagePack.Guidelines for Writing an IANA Considerations Section in RFCsMany protocols make use of points of extensibility that use constants to identify various protocol parameters. To ensure that the values in these fields do not have conflicting uses and to promote interoperability, their allocations are often coordinated by a central record keeper. For IETF protocols, that role is filled by the Internet Assigned Numbers Authority (IANA).To make assignments in a given registry prudently, guidance describing the conditions under which new values should be assigned, as well as when and how modifications to existing values can be made, is needed. This document defines a framework for the documentation of these guidelines by specification authors, in order to assure that the provided guidance for the IANA Considerations is clear and addresses the various issues that are likely in the operation of a registry.This is the third edition of this document; it obsoletes RFC 5226.Recommendation ITU-T X.1520 (2014), Common vulnerabilities and exposuresInformation technology - Software asset management - Part 5: Overview and vocabularyInformation technology - Software asset management - Part 2: Software identification tagGuidelines for the Creation of Interoperable Software Identification (SWID) TagsNational Institute for Standards and TechnologyThe MITRE CorporationG2, IncG2, IncSemantic Versioning 2.0.0CBOR Object Signing and Encryption (COSE)Concise Binary Object Representation (CBOR) is a data format designed for small code size and small message size. There is a need for the ability to have basic security services defined for this data format. This document defines the CBOR Object Signing and Encryption (COSE) protocol. This specification describes how to create and process signatures, message authentication codes, and encryption using CBOR for serialization. This specification additionally describes how to represent cryptographic keys using CBOR.CBOR Web Token (CWT)CBOR Web Token (CWT) is a compact means of representing claims to be transferred between two parties. The claims in a CWT are encoded in the Concise Binary Object Representation (CBOR) and CBOR Object Signing and Encryption (COSE) is used for added application layer security protection. A claim is a piece of information asserted about a subject and is represented as a name/value pair consisting of a claim name and a claim value. CWT is derived from JSON Web Token (JWT) but uses CBOR rather than JSON.A Universally Unique IDentifier (UUID) URN NamespaceThis specification defines a Uniform Resource Name namespace for UUIDs (Universally Unique IDentifier), also known as GUIDs (Globally Unique IDentifier). A UUID is 128 bits long, and can guarantee uniqueness across space and time. UUIDs were originally used in the Apollo Network Computing System and later in the Open Software Foundation\'s (OSF) Distributed Computing Environment (DCE), and then in Microsoft Windows platforms.This specification is derived from the DCE specification with the kind permission of the OSF (now known as The Open Group). Information from earlier versions of the DCE specification have been incorporated into this document. [STANDARDS-TRACK]Internet Security Glossary, Version 2This Glossary provides definitions, abbreviations, and explanations of terminology for information system security. The 334 pages of entries offer recommendations to improve the comprehensibility of written material that is generated in the Internet Standards Process (RFC 2026). The recommendations follow the principles that such writing should (a) use the same term or definition whenever the same concept is mentioned; (b) use terms in their plainest, dictionary sense; (c) use terms that are already well-established in open publications; and (d) avoid terms that either favor a particular vendor or favor a particular technology or mechanism over other, competing techniques that already exist or could be developed. This memo provides information for the Internet community.Terminology for Constrained-Node NetworksThe Internet Protocol Suite is increasingly used on small devices with severe constraints on power, memory, and processing resources, creating constrained-node networks. This document provides a number of basic terms that have been useful in the standardization work for constrained-node networks.Concise data definition language (CDDL): a notational convention to express CBOR data structuresThis document proposes a notational convention to express CBOR data structures (RFC 7049). Its main goal is to provide an easy and unambiguous way to express structures for protocol messages and data formats that use CBOR.Time-Based Uni-Directional AttestationThis memo documents the method and bindings used to conduct time- based uni-directional attestation between distinguishable endpoints over the network.Definition of the ROLIE Software Descriptor ExtensionThis document extends the Resource-Oriented Lightweight Information Exchange (ROLIE) core to add the information type category and related requirements needed to support Software Record and Software Inventory use cases. The 'software-descriptor' information type is defined as a ROLIE extension. Additional supporting requirements are also defined that describe the use of specific formats and link relations pertaining to the new information type.Security Automation and Continuous Monitoring (SACM) TerminologyThis memo documents terminology used in the documents produced by SACM (Security Automation and Continuous Monitoring).The ISO-19770-2:2015 specification of SWID tags assumes the existence of a file system a software
component is installed and stored in. In the case of constrained-node networks
or network equipment this assumption might not apply. Concise software instances in the
form of (modular) firmware are often stored directly on a block device that is a hardware component
of the constrained-node or network equipment. Multiple differentiable block devices or segmented
block devices that contain parts of modular firmware components (potentially each with their own
instance version) are already common at the time of this writing.The optional attributes that annotate a firmware package address specific characteristics of pieces
of firmware stored directly on a block-device in contrast to software deployed in a file-system.
In essence, trees of relative path-elements expressed by the directory and file structure in CoSWID
tags are typically unable to represent the location of a firmware on a constrained-node (small
thing). The composite nature of firmware and also the actual composition of small things require a
set of attributes to address the identification of the correct component in a composite thing for
each individual piece of firmware. A single component also potentially requires a number of distinct
firmware parts that might depend on each other (versions). These dependencies can be limited to the
scope of the component itself or extend to the scope of a larger composite device. In addition, it
might not be possible (or feasible) to store a CoSWID tag document (permanently) on a small thing
along with the corresponding piece of firmware.To address the specific characteristics of firmware, the extension points $$payload-extension and $$evidence-extension are
used to allow for an additional type of resource description—firmware-entry—thereby increasing
the self-descriptiveness and flexibility of CoSWID. The optional use of the extension points
$$payload-extension and $$evidence-extension in respect to firmware MUST adhere to the following CDDL data definition.The members of the firmware group that constitutes the content of the firmware-entry is
based on the metadata about firmware Described in . As with every semantic
differentiation that is supported by the resource-collection type, the use of firmware-entry is
optional. It is REQUIRED not to instantiate more than one firmware-entry, as the firmware group is
used in a map and therefore only allows for unique labels.The optional cms-firmware-package member allows to include the actual firmware in the CoSWID tag
that also expresses its metadata as a byte-string. This option enables a CoSWID tag to be used as a
container or wrapper that composes both firmware and its metadata in a single document (which again
can be signed, encrypted and/or compressed). In consequence, a CoSWID tag about firmware can be
conveyed as an identifying document across endpoints or used as a reference integrity
measurement as usual. Alternatively, it can also convey an actual piece of firmware, serve its
intended purpose as a SWID tag and then - due to the lack of a location to store it - be discarded.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. CoSWID tags
require a different signature scheme than this. COSE (CBOR Object Signing and Encryption) provides the required mechanism . Concise SWID can be wrapped in a COSE Single Signer Data Object
(cose-sign1) that contains a single signature. The following CDDL defines a more restrictive subset
of header attributes allowed by COSE tailored to suit the requirements of Concise SWID.A vendor supplied signed CoSWID tag that includes hash-values for the files that compose a software
component can be used as a RIM (reference integrity measurement). A RIM is a type of declarative
guidance that can be used to assert the compliance of an endpoint by assessing the installed
software. In the context of remote attestation based on an attestation via hardware rooted trust,
a verifier can appraise the integrity of the conveyed measurements
of software components using a CoSWID RIM provided by a source, such as .
A group of SWID tags about the same (sub-)system, system entity, or (sub-)component (compare
). A RIMM manifest is a distinct document that is typically conveyed en-block and
constitutes declarative guidance in respect to a specific (target) endpoint (compare
).If multiple CoSWID compose a RIMM, the following CDDL data definition SHOULD be used.A typical requirement regarding specific instantiations of endpoints – and, as a result, specific
instantiations of software components - is a representation of the absolute path of a CoSWID tag
document in a file system in order to derive absolute paths of files represented in the
corresponding CoSWID tag. The absolute path of an evidence CoSWID tag can be included as a claim in
the header of a CBOR Web Token . Depending on the source of the token, the claim can be in
the protected or unprotected header portion.