module ietf-tpm-remote-attestation {
namespace "urn:ietf:params:xml:ns:yang:ietf-tpm-remote-attestation";
prefix "tpm";
import ietf-yang-types {
prefix yang;
}
import ietf-hardware {
prefix ietfhw;
}
import ietf-keystore {
prefix ks;
}
import ietf-tcg-algs {
prefix taa;
}
organization
"IETF RATS (Remote ATtestation procedureS) Working Group";
contact
"WG Web :
WG List :
Author : Eric Voit
Author : Henk Birkholz
Author : Michael Eckel
Author : Shwetha Bhandari
Author : Bill Sulzen
Author : Liang Xia (Frank)
Author : Tom Laffey
Author : Guy Fedorkow ";
description
"A YANG module to enable a TPM 1.2 and TPM 2.0 based
remote attestation procedure using a challenge-response
interaction model and the TPM 1.2 and TPM 2.0 Quote
primitive operations.
Copyright (c) 2020 IETF Trust and the persons identified
as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with
or without modification, is permitted pursuant to, and
subject to the license terms contained in, the Simplified
BSD License set forth in Section 4.c of the IETF Trust's
Legal Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX
(https://www.rfc-editor.org/info/rfcXXXX); see the RFC
itself for full legal notices.
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 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.";
revision "2021-03-16" {
description
"Initial version";
reference
"draft-ietf-rats-yang-tpm-charra";
}
/*****************/
/* Features */
/*****************/
feature TPMs {
description
"The device supports the remote attestation of multiple
TPM based cryptoprocessors.";
}
feature bios {
description
"The device supports the bios logs.";
reference
"https://trustedcomputinggroup.org/wp-content/uploads/
PC-ClientSpecific_Platform_Profile_for_TPM_2p0_Systems_v51.pdf
Section 9.4.5.2";
}
feature ima {
description
"The device supports Integrity Measurement Architecture logs.";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TCG_IWG_CEL_v1_r0p30_13feb2021.pdf Section 4.3";
}
feature netequip_boot {
description
"The device supports the netequip_boot logs.";
}
/*****************/
/* Typedefs */
/*****************/
typedef pcr {
type uint8 {
range "0..31";
}
description
"Valid index number for a PCR. At this point 0-31 is viable.";
}
typedef compute-node-ref {
type leafref {
path "/tpm:rats-support-structures/tpm:compute-nodes" +
"/tpm:compute-node/tpm:node-name";
}
description
"This type is used to reference a hardware node. It is quite
possible this leafref will eventually point to another YANG
module's node.";
}
typedef certificate-name-ref {
type leafref {
path "/tpm:rats-support-structures/tpm:tpms/tpm:tpm" +
"/tpm:certificates/tpm:certificate/tpm:certificate-name";
}
description
"A type which allows identification of a TPM based certificate.";
}
/******************/
/* Identities */
/******************/
identity attested_event_log_type {
description
"Base identity allowing categorization of the reasons why and
attested measurement has been taken on an Attester.";
}
identity ima {
base attested_event_log_type;
description
"An event type recorded in IMA.";
}
identity bios {
base attested_event_log_type;
description
"An event type associated with BIOS/UEFI.";
}
identity netequip_boot {
base attested_event_log_type;
description
"An event type associated with Network Equipment Boot.";
}
/*****************/
/* Groupings */
/*****************/
grouping TPM20-hash-algo {
description
"The cryptographic algorithm used to hash the TPM2 PCRs. This
must be from the list of platform supported options.";
leaf TPM20-hash-algo {
type identityref {
base taa:hash;
}
must "/tpm:rats-support-structures/tpm:attester-supported-algos"
+ "/tpm:tpm20-hash" {
error-message "Not a platform supported TPM20-hash-algo";
}
default taa:TPM_ALG_SHA256;
description
"The hash scheme that is used to hash a TPM1.2 PCR. This
must be one of those supported by a platform.";
}
}
grouping TPM12-hash-algo {
description
"The cryptographic algorithm used to hash the TPM1.2 PCRs.";
leaf TPM12-hash-algo {
type identityref {
base taa:hash;
}
must "/tpm:rats-support-structures/tpm:attester-supported-algos"
+ "/tpm:tpm12-hash" {
error-message "Not a platform supported TPM12-hash-algo";
}
default taa:TPM_ALG_SHA1;
description
"The hash scheme that is used to hash a TPM1.2 PCR. This
MUST be one of those supported by a platform. This assumes
that an algorithm other than SHA1 can be supported on some
TPM1.2 cryptoprocessor variant.";
}
}
grouping nonce {
description
"A random number intended to be used once to show freshness
and to allow the detection of replay attacks.";
leaf nonce-value {
type binary;
mandatory true;
description
"This nonce SHOULD be generated via a registered
cryptographic-strength algorithm. In consequence,
the length of the nonce depends on the hash algorithm
used. The algorithm used in this case is independent
from the hash algorithm used to create the hash-value
in the response of the attestor.";
}
}
grouping tpm12-pcr-selection {
description
"A Verifier can request one or more PCR values using its
individually created Attestation Key Certificate (AC).
The corresponding selection filter is represented in this
grouping.
Requesting a PCR value that is not in scope of the AC used,
detailed exposure via error msg should be avoided.";
leaf-list pcr-index {
/* the following XPATH must be updated to ensure that only
selectable PCRs are allowed in the RPC
must "/tpm:rats-support-structures/tpm:tpms" +
"/tpm:tpm[tpm-name = current()]" +
"/tpm:tpm[TPM12-pcrs = current()]" {
error-message "Acquiring this PCR index is not supported";
}
*/
type pcr;
description
"The numbers/indexes of the PCRs. At the moment this is limited
to 32.";
}
}
grouping tpm20-pcr-selection {
description
"A Verifier can acquire one or more PCR values, which are hashed
together in a TPM2B_DIGEST coming from the TPM2. The selection
list of desired PCRs and the Hash Algorithm is represented in
this grouping.";
list tpm20-pcr-selection {
unique "TPM20-hash-algo";
description
"Specifies the list of PCRs and Hash Algorithms that can be
returned within a TPM2B_DIGEST.";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TPM-Rev-2.0-Part-2-Structures-01.38.pdf Section 10.9.7";
uses TPM20-hash-algo;
leaf-list pcr-index {
/* the following XPATH must be updated to ensure that only
selectable PCRs are allowed in the RPC
must "/tpm:rats-support-structures/tpm:tpms" +
"/tpm:tpm[tpm-name = current()]" +
"/tpm:tpm20-pcr-bank[pcr-index = current()]" {
error-message "Acquiring this PCR index is not supported";
}
*/
type tpm:pcr;
description
"The numbers of the PCRs that which are being tracked
with a hash based on the TPM20-hash-algo.";
}
}
}
grouping certificate-name-ref {
description
"Identifies a certificate in a keystore.";
leaf certificate-name {
type certificate-name-ref;
mandatory true;
description
"Identifies a certificate in a keystore.";
}
}
grouping tpm-name {
description
"A unique TPM on a device.";
leaf tpm-name {
type string;
description
"Unique system generated name for a TPM on a device.";
}
}
grouping tpm-name-selector {
description
"One or more TPM on a device.";
leaf-list tpm-name {
type string;
config false;
description
"Name of one or more unique TPMs on a device. If this object
exists, a selection should pull only the objects related to
these TPM(s). If it does not exist, all qualifying TPMs that
are 'hardware-based' equals true on the device are selected.";
}
}
grouping node-uptime {
description
"Uptime in seconds of the node.";
leaf up-time {
type uint32;
description
"Uptime in seconds of this node reporting its data";
}
}
grouping tpm12-attestation {
description
"Contains an instance of TPM1.2 style signed cryptoprocessor
measurements. It is supplemented by unsigned Attester
information.";
uses node-uptime;
leaf TPM_QUOTE2 {
type binary;
description
"Result of a TPM1.2 Quote2 operation. This includes PCRs,
signatures, locality, the provided nonce and other data which
can be further parsed to appraise the Attester.";
reference
"TPM1.2 commands rev116 July 2007, Section 16.5";
}
}
grouping tpm20-attestation {
description
"Contains an instance of TPM2 style signed cryptoprocessor
measurements. It is supplemented by unsigned Attester
information.";
leaf TPMS_QUOTE_INFO {
type binary;
mandatory true;
description
"A hash of the latest PCR values (and the hash algorithm used)
which have been returned from a Verifier for the selected PCRs
and Hash Algorithms.";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TPM-Rev-2.0-Part-2-Structures-01.38.pdf Section 10.12.1";
}
leaf quote-signature {
type binary;
description
"Quote signature returned by TPM Quote. The signature was
generated using the key associated with the
certificate-name.";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TPM-Rev-2.0-Part-2-Structures-01.38.pdf Section 11.2.1";
}
uses node-uptime;
list unsigned-pcr-values {
description
"PCR values in each PCR bank. This might appear redundant with
the TPM2B_DIGEST, but that digest is calculated across multiple
PCRs. Having to verify across multiple PCRs does not
necessarily make it easy for a Verifier to appraise just the
minimum set of PCR information which has changed since the last
received TPM2B_DIGEST. Put another way, why should a Verifier
reconstruct the proper value of all PCR Quotes when only a
single PCR has changed?
To help this happen, if the Attester does know specific PCR
values, the Attester can provide these individual values via
'unsigned-pcr-values'. By comparing this information to the
what has previously been validated, it is possible for a
Verifier to confirm the Attester's signature while eliminating
significant processing.";
uses TPM20-hash-algo;
list pcr-values {
key pcr-index;
description
"List of one PCR bank.";
leaf pcr-index {
type pcr;
description
"PCR index number.";
}
leaf pcr-value {
type binary;
description
"PCR value.";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TPM-Rev-2.0-Part-2-Structures-01.38.pdf Section 10.9.7";
}
}
}
}
grouping log-identifier {
description
"Identifier for type of log to be retrieved.";
leaf log-type {
type identityref {
base attested_event_log_type;
}
mandatory true;
description
"The corresponding measurement log type identity.";
}
}
grouping boot-event-log {
description
"Defines an event log corresponding to the event that extended
the PCR";
leaf event-number {
type uint32;
description
"Unique event number of this event";
}
leaf event-type {
type uint32;
description
"log event type";
}
leaf pcr-index {
type pcr;
description
"Defines the PCR index that this event extended";
}
list digest-list {
description
"Hash of event data";
leaf hash-algo {
type identityref {
base taa:hash;
}
description
"The hash scheme that is used to compress the event data in
each of the leaf-list digest items.";
}
leaf-list digest {
type binary;
description
"The hash of the event data using the algorithm of the
'hash-algo' against 'event data'.";
}
}
leaf event-size {
type uint32;
description
"Size of the event data";
}
leaf-list event-data {
type uint8;
description
"The event data size determined by event-size";
}
}
grouping bios-event-log {
description
"Measurement log created by the BIOS/UEFI.";
list bios-event-entry {
key event-number;
description
"Ordered list of TCG described event log
that extended the PCRs in the order they
were logged";
uses boot-event-log;
}
}
grouping ima-event {
description
"Defines an hash log extend event for IMA measurements";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TCG_IWG_CEL_v1_r0p30_13feb2021.pdf Section 4.3";
leaf event-number {
type uint64;
description
"Unique number for this event for sequencing";
}
leaf ima-template {
type string;
description
"Name of the template used for event logs
for e.g. ima, ima-ng, ima-sig";
}
leaf filename-hint {
type string;
description
"File that was measured";
}
leaf filedata-hash {
type binary;
description
"Hash of filedata";
}
leaf filedata-hash-algorithm {
type string;
description
"Algorithm used for filedata-hash";
}
leaf template-hash-algorithm {
type string;
description
"Algorithm used for template-hash";
}
leaf template-hash {
type binary;
description
"hash(filedata-hash, filename-hint)";
}
leaf pcr-index {
type pcr;
description
"Defines the PCR index that this event extended";
}
leaf signature {
type binary;
description
"The file signature";
}
}
grouping ima-event-log {
description
"Measurement log created by IMA.";
list ima-event-entry {
key event-number;
description
"Ordered list of ima event logs by event-number";
uses ima-event;
}
}
grouping netequip-boot-event {
description
"Defines an hash log extend event for Network Equipment Boot.";
leaf event-number {
type uint64;
description
"Unique number for this event for sequencing";
}
leaf filename-hint {
type string;
description
"File that was measured";
}
leaf filedata-hash {
type binary;
description
"Hash of filedata";
}
leaf filedata-hash-algorithm {
type string;
description
"Algorithm used for filedata-hash.";
}
leaf file-version {
type string;
description
"File version information.";
}
leaf file-type {
type string;
description
"Indicating at which boot stage the file is loaded,
such as BIOS, BootLoader, etc.";
}
leaf pcr-index {
type pcr;
description
"Defines the PCR index that this event extended";
}
}
grouping network-equipment-boot-event-log {
description
"Measurement log created by Network Equipment Boot.";
list boot-event-entry {
key event-number;
description
"Ordered list of Network Equipment Boot event logs
by event-number.";
uses netequip-boot-event;
}
}
grouping event-logs {
description
"A selector for the log and its type.";
choice attested_event_log_type {
mandatory true;
description
"Event log type determines the event logs content.";
case bios {
if-feature "bios";
description
"BIOS/UEFI event logs";
container bios-event-logs {
description
"BIOS/UEFI event logs";
uses bios-event-log;
}
}
case ima {
if-feature "ima";
description
"IMA event logs.";
container ima-event-logs {
description
"IMA event logs.";
uses ima-event-log;
}
}
case netequip_boot {
if-feature "netequip_boot";
description
"Network Equipment Boot event logs";
container boot-event-logs {
description
"Network equipment boot event logs.";
uses network-equipment-boot-event-log;
}
}
}
}
/**********************/
/* RPC operations */
/**********************/
rpc tpm12-challenge-response-attestation {
if-feature "taa:TPM12";
description
"This RPC accepts the input for TSS TPM 1.2 commands made to the
attesting device.";
input {
container tpm12-attestation-challenge {
description
"This container includes every information element defined
in the reference challenge-response interaction model for
remote attestation. Corresponding values are based on
TPM 1.2 structure definitions";
uses tpm12-pcr-selection;
uses nonce;
leaf-list certificate-name {
if-feature "tpm:TPMs";
type certificate-name-ref;
must "/tpm:rats-support-structures/tpm:tpms" +
"/tpm:tpm[tpm:tpm-firmware-version='taa:tpm12']" +
"/tpm:certificates/" +
"/tpm:certificate[certificate-name-ref=current()]" {
error-message "Not an available TPM1.2 AIK certificate.";
}
description
"When populated, the RPC will only get a Quote for the
TPMs associated with these certificate(s).";
}
}
}
output {
list tpm12-attestation-response {
unique "certificate-name";
description
"The binary output of TPM 1.2 TPM_Quote/TPM_Quote2, including
the PCR selection and other associated attestation evidence
metadata";
uses certificate-name-ref {
description
"Certificate associated with this tpm12-attestation.";
}
uses tpm12-attestation;
}
}
}
rpc tpm20-challenge-response-attestation {
if-feature "taa:TPM20";
description
"This RPC accepts the input for TSS TPM 2.0 commands of the
managed device. ComponentIndex from the hardware manager YANG
module to refer to dedicated TPM in composite devices,
e.g. smart NICs, is still a TODO.";
input {
container tpm20-attestation-challenge {
description
"This container includes every information element defined
in the reference challenge-response interaction model for
remote attestation. Corresponding values are based on
TPM 2.0 structure definitions";
uses nonce;
uses tpm20-pcr-selection;
leaf-list certificate-name {
if-feature "tpm:TPMs";
type certificate-name-ref;
must "/tpm:rats-support-structures/tpm:tpms" +
"/tpm:tpm[tpm:tpm-firmware-version='taa:tpm20']" +
"/tpm:certificates/" +
"/tpm:certificate[certificate-name-ref=current()]" {
error-message "Not an available TPM2.0 AIK certificate.";
}
description
"When populated, the RPC will only get a Quote for the
TPMs associated with the certificates.";
}
}
}
output {
list tpm20-attestation-response {
unique "certificate-name";
description
"The binary output of TPM2b_Quote in one TPM chip of the
node which identified by node-id. An TPMS_ATTEST structure
including a length, encapsulated in a signature";
uses certificate-name-ref {
description
"Certificate associated with this tpm20-attestation.";
}
uses tpm20-attestation;
}
}
}
rpc log-retrieval {
description
"Logs Entries are either identified via indices or via providing
the last line received. The number of lines returned can be
limited. The type of log is a choice that can be augmented.";
input {
list log-selector {
description
"Selection of log entries to be reported.";
uses tpm-name-selector;
choice index-type {
description
"Last log entry received, log index number, or timestamp.";
case last-entry {
description
"The last entry of the log already retrieved.";
leaf last-entry-value {
type binary;
description
"Content of an log event which matches 1:1 with a
unique event record contained within the log. Log
entries subsequent to this will be passed to the
requester. Note: if log entry values are not unique,
this MUST return an error.";
}
}
case index {
description
"Numeric index of the last log entry retrieved, or
zero.";
leaf last-index-number {
type uint64;
description
"The last numeric index number of a log entry.
Zero means to start at the beginning of the log.
Entries subsequent to this will be passed to the
requester.";
}
}
case timestamp {
leaf timestamp {
type yang:date-and-time;
description
"Timestamp from which to start the extraction. The
next log entry subsequent to this timestamp is to
be sent.";
}
description
"Timestamp from which to start the extraction.";
}
}
leaf log-entry-quantity {
type uint16;
description
"The number of log entries to be returned. If omitted, it
means all of them.";
}
}
uses log-identifier;
}
output {
container system-event-logs {
description
"The requested data of the measurement event logs";
list node-data {
unique "tpm-name";
description
"Event logs of a node in a distributed system
identified by the node name";
uses tpm-name;
uses node-uptime;
container log-result {
description
"The requested entries of the corresponding log.";
uses event-logs;
}
}
}
}
}
/**************************************/
/* Config & Oper accessible nodes */
/**************************************/
container rats-support-structures {
description
"The datastore definition enabling verifiers or relying
parties to discover the information necessary to use the
remote attestation RPCs appropriately.";
container compute-nodes {
if-feature "tpm:TPMs";
description
"Holds the set device subsystems/components in this composite
device that support TPM operations.";
list compute-node {
key node-id;
config false;
min-elements 2;
description
"A component within this composite device which
supports TPM operations.";
leaf node-id {
type string;
description
"ID of the compute node, such as Board Serial Number.";
}
leaf node-physical-index {
if-feature ietfhw:entity-mib;
type int32 {
range "1..2147483647";
}
config false;
description
"The entPhysicalIndex for the compute node.";
reference
"RFC 6933: Entity MIB (Version 4) - entPhysicalIndex";
}
leaf node-name {
type string;
description
"Name of the compute node.";
}
leaf node-location {
type string;
description
"Location of the compute node, such as slot number.";
}
}
}
container tpms {
description
"Holds the set of TPMs within an Attester.";
list tpm {
key tpm-name;
unique "tpm-path";
description
"A list of TPMs in this composite device that RATS
can be conducted with.";
uses tpm-name;
leaf hardware-based {
type boolean;
config false;
description
"Answers the question: is this TPM is a hardware based
TPM?";
}
leaf tpm-physical-index {
if-feature ietfhw:entity-mib;
type int32 {
range "1..2147483647";
}
config false;
description
"The entPhysicalIndex for the TPM.";
reference
"RFC 6933: Entity MIB (Version 4) - entPhysicalIndex";
}
leaf tpm-path {
type string;
config false;
description
"Path to a unique TPM on a device. This can change across
reboots.";
}
leaf compute-node {
if-feature "tpm:TPMs";
type compute-node-ref;
config false;
mandatory true;
description
"Indicates the compute node measured by this TPM.";
}
leaf tpm-manufacturer {
type string;
config false;
description
"TPM manufacturer name.";
}
leaf tpm-firmware-version {
type identityref {
base taa:cryptoprocessor;
}
mandatory true;
description
"Identifies the cryptoprocessor API set supported. This
is automatically configured by the device and should not
be changed.";
}
uses TPM12-hash-algo {
when "tpm-firmware-version = 'taa:tpm12'";
refine TPM12-hash-algo {
description
"The hash algorithm overwrites the default used for PCRs
on this TPM1.2 compliant cryptoprocessor.";
}
}
leaf-list TPM12-pcrs {
when "../tpm-firmware-version = 'taa:tpm12'";
type pcr;
description
"The PCRs which may be extracted from this TPM1.2
compliant cryptoprocessor.";
}
list tpm20-pcr-bank {
when "../tpm-firmware-version = 'taa:tpm20'";
key "TPM20-hash-algo";
description
"Specifies the list of PCRs that may be extracted for
a specific Hash Algorithm on this TPM2 compliant
cryptoprocessor. A bank is a set of PCRs which are
extended using a particular hash algorithm.";
reference
"https://www.trustedcomputinggroup.org/wp-content/uploads/
TPM-Rev-2.0-Part-2-Structures-01.38.pdf Section 10.9.7";
leaf TPM20-hash-algo {
type identityref {
base taa:hash;
}
must "/tpm:rats-support-structures"
+ "/tpm:attester-supported-algos"
+ "/tpm:tpm20-hash" {
error-message "Not a platform supported TPM20-hash-algo";
}
description
"The hash scheme actively being used to hash a
one or more TPM2.0 PCRs.";
}
leaf-list pcr-index {
type tpm:pcr;
description
"Defines what TPM2 PCRs are available to be extracted.";
}
}
leaf tpm-status {
type enumeration {
enum operational {
value 0;
description
"The TPM currently is currently running normally and
is ready to accept and process TPM quotes.";
reference
"TPM-Rev-2.0-Part-1-Architecture-01.07-2014-03-13.pdf
Section 12";
}
enum non-operational {
value 1;
description
"TPM is in a state such as startup or shutdown which
precludes the processing of TPM quotes.";
}
}
config false;
mandatory true;
description
"TPM chip self-test status.";
}
container certificates {
description
"The TPM's certificates, including EK certificates
and AK certificates.";
list certificate {
key "certificate-name";
description
"Three types of certificates can be accessed via
this statement, including Initial Attestation
Key Cert, Local Attestation Key Cert or
Endorsement Key Cert.";
leaf certificate-name {
type string;
description
"An arbitrary name uniquely identifying a certificate
associated within key within a TPM.";
}
leaf certificate-keystore-ref {
type leafref {
path "/ks:keystore/ks:asymmetric-keys/ks:asymmetric-key"
+ "/ks:certificates/ks:certificate/ks:name";
}
description
"A reference to a specific certificate of an
asymmetric key in the Keystore.";
/* Note: It is also possible to import a grouping which
allows local definition via an imported keystore
schema. */
}
leaf certificate-type {
type enumeration {
enum endorsement-cert {
value 0;
description
"Endorsement Key (EK) Certificate type.";
}
enum initial-attestation-cert {
value 1;
description
"Initial Attestation key (IAK) Certificate type.";
}
enum local-attestation-cert {
value 2;
description
"Local Attestation Key (LAK) Certificate type.";
}
}
description
"Type of this certificate";
}
}
}
}
}
container attester-supported-algos {
description
"Identifies which TPM algorithms are available for use on an
attesting platform.";
leaf-list tpm12-asymmetric-signing {
when "../../tpm:tpms" +
"/tpm:tpm[tpm:tpm-firmware-version='taa:tpm12']";
if-feature "taa:TPM12";
type identityref {
base taa:asymmetric;
}
description
"Platform Supported TPM12 asymmetric algorithms.";
}
leaf-list tpm12-hash {
when "../../tpm:tpms" +
"/tpm:tpm[tpm:tpm-firmware-version='taa:tpm12']";
if-feature "taa:TPM12";
type identityref {
base taa:hash;
}
description
"Platform supported TPM12 hash algorithms.";
}
leaf-list tpm20-asymmetric-signing {
when "../../tpm:tpms" +
"/tpm:tpm[tpm:tpm-firmware-version='taa:tpm20']";
if-feature "taa:TPM20";
type identityref {
base taa:asymmetric;
}
description
"Platform Supported TPM20 asymmetric algorithms.";
}
leaf-list tpm20-hash {
when "../../tpm:tpms" +
"/tpm:tpm[tpm:tpm-firmware-version='taa:tpm20']";
if-feature "taa:TPM20";
type identityref {
base taa:hash;
}
description
"Platform supported TPM20 hash algorithms.";
}
}
}
}