RATS Working Group H. Birkholz
Internet-Draft Fraunhofer SIT
Intended status: Standards Track P. Uiterwijk
Expires: January 14, 2021 Red Hat
N. Smith
Intel
J. Fitzgerald-McKay
Department of Defense
D. Waltermire
NIST
S. Bhandari
Cisco
July 13, 2020
Reference Integrity Measurement Extension for Concise Software
Identities
draft-birkholz-rats-coswid-rim-01
Abstract
Concise Software Identification (CoSWID) tags identify and describe
individual software components, patches, and installation bundles.
CoSWID is based on ISO/IEC 19770-2:2015 2:2015 that provides a
complementary XML schema definition (XSD) for Software Identification
(SWID) tags. CoSWID supports the same features as the corresponding
XML SWID tags. The CoSWID specification also includes more
structured extensibility features and reduces a few of ambiguities
that are not explicitly resolved in the ISO XSD. In this document,
these extensibility features (extension points) are used to add
attributes to the CoSWID specification. The new attributes allow for
the use of CoSWID as Reference Integrity Measurements (RIM). There
are four sets of RIM features defined in this specification. 1.)
attributes that support RIM manifests for Measured Boot, 2.)
attributes that support package manager managed structures, 3.)
attributes that allow for OID to be used in the description of
Reference Integrity Measurements, and 4.) attributes for object trees
in support of Target Environments that are chained via Layered
Attestation.
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
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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 January 14, 2021.
Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
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described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Requirements Notation . . . . . . . . . . . . . . . . . . 4
2. CoSWID Attribute Extensions . . . . . . . . . . . . . . . . . 5
2.1. RIM requirements on existing CoSWID attributes . . . . . 5
2.2. RIM Extensions for Measured Boot . . . . . . . . . . . . 5
2.3. RIM Extensions for Software Package Management . . . . . 11
2.4. RIM Extensions for Composite Device . . . . . . . . . . . 12
2.4.1. The tcb-info Group . . . . . . . . . . . . . . . . . 12
2.4.2. CoSWID Version Scheme for RPM . . . . . . . . . . . . 14
2.5. Additional Measurement Attributes for CoSWID . . . . . . 14
2.6. CoSWID RIM CDDL . . . . . . . . . . . . . . . . . . . . . 14
3. Privacy Considerations . . . . . . . . . . . . . . . . . . . 17
4. Security Considerations . . . . . . . . . . . . . . . . . . . 18
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
6.1. Normative References . . . . . . . . . . . . . . . . . . 18
6.2. Informative References . . . . . . . . . . . . . . . . . 18
6.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
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1. Introduction
Reference Integrity Measurements describe the intended state of
(composite) software components installed on a (composite) device. A
measurement of all installed software components of a devices allows
for assertions about the trustworthiness of the given device. In
combination with a root of trust (RoT) for reporting (RTR), these
measurements can be refined into evidence and enable IETF Remote
ATtestation procedureS (RATS). RATS support the decision process of
whether to put trust in the trustworthiness of a device - or not.
The RATS architecture [I-D.ietf-rats-architecture] defines the roles
Verifiers, Attesters, Endorsers, and Relying Parties. The RATS
architecture also specifies that Attestation Evidence is created by
Attesters and consumed by Verifiers. Ultimately, the goal is to
enable a Relying Party to put trust in the trustworthiness of a
remote peer (the Attester). Attestation Evidence is composed of
believable assertions about an Attester's trustworthiness
characteristics. In RATS, these assertions are called Claims. The
Verifier conducts a set of appraisal procedures in order to assess
the compliance of an Attester's trustworthiness characteristics.
A prominent appraisal procedure in RATS is the comparison of Claim
values included in Attestation Evidence with Reference Claim values
provided by Endorsers (e.g. supply chain entities). The comparison
of Claim values via Reference Claim values is vital for the
assessment of compliance metrics with respect to software components
installed on an Attester. A typical objective here is the
remediation of already vulnerabilities discovered in certain versions
of software components.
The Integrity Measurement Architecture (IMA) of the Linux Security
Modules (LSM) provides a detailed Event Log (sometimes also referred
to as a Measurement Log) that retains a sequence of hash measurements
of every software sub-component (e.g. a firmware, an ELF executable,
or a configuration file) that is created and appended to the sequence
of measurements that composes the event log before the software
component in question is started or read.
In essence, to enable this appraisal procedure conducted by Verfiers
an Attester's IMA provides Event Logs that include the hash values of
every started software component and therefore are part of the
Attestation Evidence an Attester creates. The complementary well-
known-values that Verifiers require are included in the Reference
Integrity Measurements (RIM). RIMs can be provided via Software
Identification tags created by Endorsers, such as the software
creators, manufacturers, vendors, or other trusted third parties
(e.g. supply chain or certification entities).
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This document provides an extension to the CoSWID specification
defined in [I-D.ietf-sacm-coswid]. The extension adds attributes to
CoSWID tags that enable them to express RIMs. One prominent subset
of these attributes are illustrated in the TCG Reference Integrity
Manifest Information Model [ref] specification. These attributes are
added to the existing CoSWID specification via the most general
extension point the CoSWID specification provides: $$coswid-
extensions. An additional map definition named "reference-
measurements" is added and is defined in section [ref] of this
document. Another prominent subset is the addition of an object tree
next to the file system tree as defined by [I-D.ietf-sacm-coswid].
The object tree enables the representation of multiple layered
execution environments as described by the Layered Attestation
concept in the RATS architecture [I-D.ietf-rats-architecture].
Furthermore, a usage profile for signed CoSWID tags is defined in
this specification in support of the software-component structure of
systems managed by package managers. Signed CoSWID tags that are
aligned with that software model can be used to describe the contents
of one or multiple of the packages that make up the contents of a
system. In this case, it may be that multiple CoSWID tags are
provided as Reference Claim values for a attestation by a single
Attester. In order to minimize the impact on the sizes of packages,
it is likely that any CoSWID tags delivered as part of packages as
part of a package manager managed system will not contain actual
reference values, but instead a link-entry to a CoSWID tag published
by the vendor in a repository.
Reference Integrity Measurements are a subset of the Conceptual
Messages defined as Endorsements. RIMs provide a vital resource to
be consumed by Verifiers in conjunction with Appraisal Policies and
Evidence. While RIMs represent nominal values, Appraisal Policies
represent imperative guidance how to use nominal values in an
appraisal procedure. Evidence represents assertions about the
trustworthiness of a device's Target Environments created by its own
Attesting Environment. As Evidence can be rather complex and its
appraisal therefore a burden for Relying Parties that are interested
in trustworthiness evaluations, Verifies take on this duty and create
easier to digest Attestation Results for Relying Parties. In
consequence, Verifiers are the entities that have to put trust in the
provenance and integrity of RIMs - and Endorsements in general -
relying on proof of integrity and authenticity.
1.1. 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
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BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2. CoSWID Attribute Extensions
This specification defines four types of attribute sets that can be
added to the CoSWID specification via its defined extension points.
1. Attributes that support RIM manifests for Measured Boot (often
referred to as Secure Boot),
2. Attributes that support the RPM package manager structure,
3. Attributes that allow to represent composite devices including
several Target Environments, and
4. Attributes that allow for OID to be used in the description of
Reference Integrity Measurements.
2.1. RIM requirements on existing CoSWID attributes
As defined by NIST IR 8060 [ref], there are required "Meta
Attributes" for XML SWID tags that have to be included in a SWID tag
in order to compose a valid SWID RIM. In this section, these
attributes are mapped to CoSWID attributes and corresponding
requirements on attributes defined in the CoSWID specification to
compose valid NIST IR 8060 signed Payload content in the Concise
Software Identity Reference Integrity Measurement (CoSWID RIM)
representation.
The 'software-meta-entry' type defined in the CoSWID specification
includes the optional members 'product', 'colloquial-version',
'revision', and 'edition'. These four members MUST be included in a
CoSWID RIM in order to compose a valid Reference Integrity
Measurement in alignment with NIST IR 8060. Furthermore, the
semantics of the text (tstr) typed values MUST convey content that
allows for semantic interoperability in a given scope (e.g., an
administrative domain). The software-meta-entries provide vital
support for steering decisions made by the RATS verifier role in
order to enable discovery and matching of related or additional
CoSWID RIM available to or discoverable by the verifier.
2.2. RIM Extensions for Measured Boot
The following attributes are derived from the TCG Reference Integrity
Manifest Information Model [ref] specification. These attributes
support the creation of very small CoSWID RIM tags that enable the
Remote Integrity Verification (RIV
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[I-D.fedorkow-rats-network-device-attestation]) of small things,
i.e., constrained devices in constrained network environments. In
consequence, the majority of the attributes listed in this section
represent metadata about firmware and supply chain entities that
provide firmware for a device (platform). Analogously to the
mandated software-meta-entries illustrated above, the attributes
defined in the table below provide more context and enable steering
decisions for the appraisal procedures of a Verifier. Consecutively,
RIM have to be managed and curated in a consistent manner so that
there is no significant threshold for a Verifier to make use of them
during an appraisal procedure.
The design of the additional RIM attributes in this section is
motivated by the vast variety of identifier types used in production
today, e.g. endorsement documents [I-D.ietf-rats-architecture] that
are enrolled or on-boarded on the Attester itself. It is vital to
highlight that this variety can render semantic self-descriptiveness
more difficult. Most importantly though: interoperability beats
self-descriptiveness. A convergence towards a common identification
scheme with respect to software components and its subset that is
firmware is highly encouraged - alas not achieved at the time of
creating this proposed standard. The following table defines the
semantics of the set of new members that are added via the reference-
measurement-entry map. The reference-measurement-entry map is added
using the $$coswid-extension CDDL extension point.
+--------------------------------+----------+-----------------------+
| Attribute Name | Quantity | Description |
+--------------------------------+----------+-----------------------+
| payload-type | 0-1 | The value of this |
| | | attribute MUST be one |
| | | equivalent of the |
| | | following three |
| | | choices. 'direct': |
| | | the representation |
| | | used in this RIM (and |
| | | referred RIMs) is |
| | | using the CoSWID |
| | | encoding as its |
| | | representation. |
| | | 'indirect': the |
| | | representation used |
| | | in referred RIMs |
| | | ('Support RIMs) is |
| | | using a different |
| | | representation than |
| | | CoSWID as it's |
| | | encoding. |
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| | | Analogously, a |
| | | reference to the |
| | | corresponding |
| | | specification MUST be |
| | | provided if the value |
| | | is set to an |
| | | equivalent of |
| | | 'indirect' (see |
| | | binding-spec-name and |
| | | binding-spec- |
| | | version). 'hybrid': |
| | | the representation |
| | | used in the referred |
| | | RIMs ('Support RIMs') |
| | | is a mix of CoSWID |
| | | representations and |
| | | other |
| | | representations. In |
| | | this case, a |
| | | reference to the |
| | | representation used |
| | | MUST be included - |
| | | even if it is the |
| | | CoSWID representation |
| | | - for every Support |
| | | RIM (see 'binding- |
| | | spec-name' and |
| | | 'binding-spec- |
| | | version' definition |
| | | in this table). |
| | | |
| platform-configuration-uri- | 0-1 | A byte-comparable |
| global | | reference to a |
| | | Platform |
| | | Configuration URI as |
| | | defined by the TCG |
| | | Platform Certificate |
| | | Profile [ref TCG |
| | | Platform Certificate |
| | | Profile, Version 1.1] |
| | | for X.509v3 |
| | | certificates that |
| | | MUST be identical to |
| | | the URI included in a |
| | | TCG Platform |
| | | Certificate pointing |
| | | to a resource |
| | | providing a copy of |
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| | | the CoSWID RIM this |
| | | attribute is included |
| | | in. |
| | | |
| platform-configuration-uri- | 0-1 | A byte-comparable |
| local | | reference to a |
| | | Platform |
| | | Configuration URI |
| | | defined by the TCG |
| | | Platform Certificate |
| | | Profile [ref TCG |
| | | Platform Certificate |
| | | Profile, Version 1.1] |
| | | that MUST represent |
| | | the resource at which |
| | | a copy of this CoSWID |
| | | RIM can be found |
| | | within the |
| | | (composite) |
| | | device/platform |
| | | itself. |
| | | |
| binding-spec-name | 1 | If the value of |
| | | 'payload-type' is an |
| | | equivalent to the |
| | | enumeration |
| | | 'indirect', the value |
| | | of this attribute |
| | | MUST contain a global |
| | | unique text (tstr) |
| | | identifier referring |
| | | to the specification |
| | | that defines the |
| | | representation of the |
| | | referred RIM in order |
| | | to enable its |
| | | decoding. |
| | | |
| binding-spec-version | 1 | If the value of |
| | | 'payload-type' is an |
| | | equivalent to the |
| | | enumeration |
| | | 'indirect', the value |
| | | of this attribute |
| | | MUST contain a unique |
| | | version number with |
| | | respect to the |
| | | specification |
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| | | represented in the |
| | | value of 'binding- |
| | | spec-name'. |
| | | |
| platform-manufacturer-id | 0-1 | An identifier based |
| | | on the IANA Private |
| | | Enterprise Number |
| | | registry that is |
| | | assigned to firmware |
| | | manufacturer. This |
| | | identifier MUST be |
| | | included unless the |
| | | firmware manufacturer |
| | | and the platform |
| | | manufacturer are |
| | | represented by the |
| | | same text (tstr) |
| | | value. Analogously, |
| | | if the firmware |
| | | manufacturer and the |
| | | platform manufacturer |
| | | are represented via |
| | | the same text (tstr) |
| | | value, this attribute |
| | | MAY be omitted. |
| | | |
| platform-manufacturer-name | 0-1 | An identifier number |
| | | (uint) value that |
| | | uniquely represents |
| | | the firmware |
| | | manufacturer. This |
| | | identifier MUST be |
| | | included unless the |
| | | firmware manufacturer |
| | | and the platform |
| | | manufacturer are |
| | | represented via the |
| | | same number (unit) |
| | | value, this attribute |
| | | MAY be omitted. |
| | | |
| platform-model-name | 1 | An identifier text |
| | | (tstr) value enabling |
| | | the identification of |
| | | a certain device |
| | | model/type composite. |
| | | The reliability of |
| | | this identifier is |
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| | | not absolute. In |
| | | consequence this |
| | | identifier MUST NOT |
| | | be omitted. In an |
| | | case, the use of this |
| | | identifier requires |
| | | foresight and |
| | | preparation as it's |
| | | purpose supports |
| | | semantic |
| | | interoperability. |
| | | Arbitrary, |
| | | conflicting, or |
| | | unresolvable values |
| | | SHOULD be avoided. |
| | | |
| platform-version | 0-1 | A byte-comparable |
| | | reference to a |
| | | Platform |
| | | Certificate's |
| | | 'Manufacturer- |
| | | Specific Identifier' |
| | | extension value [ref |
| | | TCG Platform |
| | | Certificate Profile, |
| | | Version 1.1]. |
| | | |
| firmware-manufacturer-id | 0-1 | An IANA defined |
| | | unique value that is |
| | | a Private Enterprise |
| | | Number (Platform |
| | | manufacturer unique |
| | | identifier) that |
| | | SHOULD be included in |
| | | a CoSWID RIM that |
| | | covers firmware. |
| | | |
| firmware-manufacturer-name | 0-1 | An identifier that is |
| | | represented as the |
| | | name of a platform |
| | | manufacturer via a |
| | | text (tstr) value |
| | | that SHOULD be |
| | | included in a CoSWID |
| | | RIM that covers |
| | | firmware. |
| | | |
| firmware-model-name | 0-1 | An identifier that |
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| | | represents the target |
| | | platform model via a |
| | | text (tstr) value |
| | | that SHOULD be |
| | | included in a CoSWID |
| | | RIM. |
| | | |
| firmware-version | 0-1 | An identifier that is |
| | | represented as the |
| | | version number of a |
| | | specific firmware |
| | | version corresponding |
| | | to a given set of |
| | | platform identifiers |
| | | and SHOULD be |
| | | included in a CoSWID |
| | | RIM. |
| | | |
| boot-events | 0-1 | A reference to the |
| | | platform measured |
| | | boot event logs that |
| | | can be compared to |
| | | individual events |
| | | from the platform |
| | | measured boot events |
| | | collected at platform |
| | | runtime. |
+--------------------------------+----------+-----------------------+
2.3. RIM Extensions for Software Package Management
To enable very small CoSWID tags that basically are signed references
to full Base RIMs for each software package that ultimately include
all the hash values required by the appraisal procedure of a
Verifier, the member rim-reference is added using the $$payload-
extension CDDL extension point.
+---------------+----------+----------------------------------------+
| Attribute | Quantity | Description |
| Name | | |
+---------------+----------+----------------------------------------+
| rim-reference | 0-1 | A URI pointing to the CoSWID Base RIM |
| | | that will list the payload reference |
| | | measurements (hashes) in case of a |
| | | minimal CoSWID tag. |
+---------------+----------+----------------------------------------+
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2.4. RIM Extensions for Composite Device
Attesters that are composite devices can include several Target
Environments. Some of these Target Environments can take on the
duties of Attesting Environments during a boot sequence as described
in section 4.3. of the RATS architecture
[I-D.ietf-rats-architecture]. The corresponding procedure is called
Layered Attestation and requires a dedicated RIM for each Target
Environment of the Attester. The addition of object tree attributes
to CoSWID using the $$resource-collection-extension extension point
addresses the resulting requirements.
Each Target Environment involved in Layered Attestation can be
considered its own Trusted Computing Base (TCB) [ref]. TCB metadata
can be used to identify or locate RIMs. The addition of TCB
information to the new object tree structure is in support of these
identifiers for RIM discovery.
Additionally, software components started in these Target
Environments might not be referenceable via a filesystem (e.g., in
the case of firmware). To enable RIMs to represent firmware items
that are not associated with a filesystem, attributes for object
trees are added to the existing filesystem items tree.
2.4.1. The tcb-info Group
Every object in the object tree can be represented with a set of
metadata items pertaining a specific TCB. The following items can be
associated with a dedicate object-entry:
+-----------------------+----------+--------------------------------+
| Attribute Name | Quantity | Description |
+-----------------------+----------+--------------------------------+
| tcb-info.id | 1 | A hash of the tcb-info.key- |
| | | elements value including the |
| | | map structure |
| | | |
| tcb-info.key-elements | 1 | A collection of attributes |
| | | that disambiguates the various |
| | | TCB objects in a composite |
| | | device scope |
| | | |
| tcb-info.vendor | 1 | The entity that named the |
| | | measurement of the Target |
| | | Environment TCB referenced by |
| | | an object-entry |
| | | |
| tcb-info.model | 0-1 | The product name associated |
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| | | with the object-entry in a |
| | | measurement |
| | | |
| tcb-info.layer | 0-1 | The layer in the composite |
| | | devive (and therefore object |
| | | tree) of the TCB associated |
| | | with the object-entry in a |
| | | measurement |
| | | |
| tcb-info.index | 0-1 | An index that enumerates |
| | | TCB/object-entries in a CoSWID |
| | | RIM tag |
| | | |
| tcb-info.type | 1 | A machine-readable description |
| | | of the measurement |
| | | |
| tcb-info.version | 0-1 | A revision string associated |
| | | with the measurement and a |
| | | reference value |
| | | |
| tcb-info.SVN | 0-1 | The security version number |
| | | associated with the |
| | | measurement and a reference |
| | | value |
| | | |
| tcb-info.flags | 0-1 | Operational states associated |
| | | with a TCB or composite device |
| | | that affects the object being |
| | | measured. If omitted, the TCB |
| | | or omposite device is not |
| | | capable of entering this |
| | | state. Valid states are: not- |
| | | configured, not-secure, |
| | | recovery, debug. |
| | | |
| tcb-info.fwids | 0-1 | A list of digests resulting |
| | | from applying the hash |
| | | algorithm over the object |
| | | being measured |
| | | |
| tcb-info.vendorinfo | 0-1 | Actual values or state that is |
| | | associated with a TVB element |
| | | |
| tcb-info.vendormask | 0-1 | A mask that allows a Verifier |
| | | to ignore a subset of |
| | | collected tcb-info.vendorinfo |
| | | values that the Endorser |
| | | asserts are not security |
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| | | relevant |
+-----------------------+----------+--------------------------------+
2.4.2. CoSWID Version Scheme for RPM
To enable encoding version information into a CoSWID of RPM packages,
the SWID version scheme value index TBD1 has been registered. RPM
versions are defined as epoch:version-release-architecture, where the
"epoch:" component is optional. Epoch is a numerical value, which
should be considered zero if the epoch component is missing. Version
and Release can be any string as long as they do not contain a hyphen
(-). Architecture is an alphanumerical string.
Sorting of RPM versions is a multi-step process: - The epoch, version
and release components are compared in that order, as soon as a
difference is found, that is the overall difference. - The epoch
component is compared as integers. A higher number means a higher
version. - The version and release components are compared
alphabetically, until a digit is encountered in both strings, at
which point as many digits are consumed from both to form an integer,
which is then compared. If the integers are identical, the
comparison continues alphabetically. - The architecture component is
never sorted. If they are different between two versions, the
versions are inequal, not higher or lower.
2.5. Additional Measurement Attributes for CoSWID
[I-D.ietf-sacm-coswid] specifies a well-defined file hash structure
for integrity measurements of individual files in a file-system.
This documents extends this feature to all additional members of the
resource-collection group: 'directory', 'resource', and 'process'.
These new well-defined measurement options extend the scope of RIM to
(sub-)trees of files, software running in memory (e.g. available from
Trusted Execution Environments, such as SGX enclaves), and even
external resources, such as remote services of collections of RIM
bundles.
2.6. CoSWID RIM CDDL
The following CDDL specification uses the existing CDDL extension
points as defined in [I-D.ietf-sacm-coswid]:
o $$coswid-extension
o $$payload-extension
o $$directory-extension
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o $$resource-extension
o $$process-extension
o $$link-extension
o $$resource-collection-extension
<CODE BEGINS>
$$coswid-extension //= (reference-measurement => reference-measurement-entry)
reference-measurement-entry = {
? payload-type => direct / indirect / hybrid,
? platform-configuration-uri-global => any-uri,
? platform-configuration-uri-local => any-uri,
binding-spec-name => text,
binding-spec-version => text,
platform-manufacturer-id => uint,
platform-manufacturer-name => text,
platform-model-name => text,
? platform-version => uint,
? firmware-manufacturer-id => uint,
? firmware-manufacturer-name => text,
? firmware-model-name => text,
? firmware-version => uint,
? boot-events => [ * boot-event-entry ],
rim-link-hash => bytes,
}
boot-event-entry = {
boot-event-number => uint,
boot-event-type => uint,
boot-digest-list => [ 1* hash-entry ],
boot-event-data => bytes
}
$$payload-extension //= ( ? support-rim-type-kramdown => direct / indirect )
$$payload-extension //= ( ? support-rim-format => text )
$$payload-extension //= ( ? support-rim-uri-global => any-uri )
$$payload-extension //= ( ? rim-reference => any-uri )
reference-measurement = 58
payload-type = 59
payload-rim = 60
platform-configuration-uri-global = 61
platform-configuration-uri-local = 62
binding-spec-name = 63
binding-spec-version = 64
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platform-manufacturer-id = 65
platform-manufacturer-name = 66
platform-model-name = 67
platform-version = 68
firmware-manufacturer-id = 69
firmware-manufacturer-name = 70
firmware-model-name = 71
firmware-version = 72
rim-link-hash = 73
support-rim-type-kramdown = 74
support-rim-format = 75
support-rim-uri-global = 76
rim-reference = 77
boot-events = 78
boot-event-number = 79
boot-event-type = 80
boot-digest-list = 81
boot-event-data = 82
direct = 0
indirect = 1
hybrid = 2
$$directory-extension //= ( ? hash => hash-entry )
$$resource-extension //= ( ? hash => hash-entry )
$$process-extension //= ( ? hash => hash-entry )
$$link-extension //= ( ? thumbprint => hash-entry )
$$resource-collection-extension //= (
? object => object-entry / [ 2* object-entry ]
)
object-entry = {
resource-collection,
tcb-info,
$$object-extension,
}
tcb-info = (
tcb-info.id => hash-entry,
tcb-info.key-elements => {
tcb-info.vendor => text,
? tcb-info.model => text,
? tcb-info.layer => int,
? tcb-info.index => int,
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tcb-info.type => tagged-bytes / uuid-bytes,
},
? tcb-info.version => text,
? tcb-info.SVN => int,
? tcb-info.flags => uint .bits tcb-info.operational-flags,
? tcb-info.fwids,
? tcb-info.vendorinfo => bytes .size 8,
? tcb-info.vendormask => bytes,
)
uuid-bytes = bytes .size 8
tcb-info.operational-flags = &(
not-configured: 0,
not-secure: 1,
recovery: 2,
debug: 3,
)
tcb-info.fwids = [
+ [ hash-alg: [ * int ] / text,
digest: bytes,
]
]
object = 83
tcb-info.id = 84
tcb-info.key-elements = 85
tcb-info.vendor = 86
tcb-info.model = 87
tcb-info.layer = 88
tcb-info.index = 89
tcb-info.type = 90
tcb-info.version = 91
tcb-info.SVN = 92
tcb-info.flags = 93
tcb-info.fwids = 94
tcb-info.vendorinfo = 95
tcb-info.vendormask = 96
<CODE ENDS>
3. Privacy Considerations
TBD
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4. Security Considerations
To be elaborated on
5. IANA Considerations
This document has added the following entries to the SWID/CoSWID
Version Scheme Values registry at https://www.iana.org/assignments/
swid [1]:
Index: TBD1
Version Scheme Name: rpm
Specification: See {{rpm-version-scheme}}
6. References
6.1. Normative References
[I-D.ietf-sacm-coswid]
Birkholz, H., Fitzgerald-McKay, J., Schmidt, C., and D.
Waltermire, "Concise Software Identification Tags", draft-
ietf-sacm-coswid-15 (work in progress), May 2020.
[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/info/rfc2119>.
[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/info/rfc8174>.
6.2. Informative References
[I-D.fedorkow-rats-network-device-attestation]
Fedorkow, G., Voit, E., and J. Fitzgerald-McKay, "TPM-
based Network Device Remote Integrity Verification",
draft-fedorkow-rats-network-device-attestation-05 (work in
progress), April 2020.
[I-D.ietf-rats-architecture]
Birkholz, H., Thaler, D., Richardson, M., Smith, N., and
W. Pan, "Remote Attestation Procedures Architecture",
draft-ietf-rats-architecture-05 (work in progress), July
2020.
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6.3. URIs
[1] https://www.iana.org/assignments/swid
Authors' Addresses
Henk Birkholz
Fraunhofer SIT
Rheinstrasse 75
Darmstadt 64295
Germany
Email: henk.birkholz@sit.fraunhofer.de
Patrick Uiterwijk
Red Hat
100 E Davie Street
Raleigh 27601
Netherlands
Email: puiterwijk@redhat.com
Ned Smith
Intel Corporation
USA
Email: ned.smith@intel.com
Jessica Fitzgerald-McKay
Department of Defense
9800 Savage Road
Ft. Meade, Maryland
USA
Email: jmfitz2@nsa.gov
David Waltermire
National Institute of Standards and Technology
100 Bureau Drive
Gaithersburg, Maryland 20877
USA
Email: david.waltermire@nist.gov
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Shwetha Bhandari
Cisco Systems, Inc.
Cessna Business Park, Sarjapura Marathalli Outer Ring Road
Bangalore, KARNATAKA 560087
India
Email: shwethab@cisco.com
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