Internet DRAFT - draft-yang-i2nsf-remote-attestation-interface-dm
draft-yang-i2nsf-remote-attestation-interface-dm
I2NSF Working Group P. Yang
Internet-Draft M. Chen
Intended status: Standards Track L. Su
Expires: 8 December 2022 China Mobile
D. Lopiz
Telefonica
J. Jeong
Sungkyunkwan University
L. Dunbar
Futurewei
6 June 2022
I2NSF Remote Attestation Interface YANG Data Model
draft-yang-i2nsf-remote-attestation-interface-dm-01
Abstract
This document describes the architecture and corresponding interfaces
of NSF remote attestation in I2NSF framework. Remote attestation of
NSFs could provide integrity assurence of NSFs deployed in remote
environment. The interfaces involved are I2NSF remote attestation
evidence interface, I2NSF remote attestation reference value
interface, and I2NSF remote attestation result interface. This
document complies with I2NSF architecture and Remote Attestation
ProcedureS (RATs) architecture.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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and may be updated, replaced, or obsoleted by other documents at any
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on 8 December 2022.
Copyright Notice
Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Terms . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
3. Scope and Motivation . . . . . . . . . . . . . . . . . . . . 4
3.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Motivation . . . . . . . . . . . . . . . . . . . . . . . 4
4. Information Model . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Architecture of I2NSF Remote Attestation . . . . . . . . 5
4.2. Root of Trust in I2NSF . . . . . . . . . . . . . . . . . 6
4.3. Verifier in I2NSF . . . . . . . . . . . . . . . . . . . . 6
4.4. Reference Value Provider in I2NSF . . . . . . . . . . . . 7
4.5. Relying Party in I2NSF . . . . . . . . . . . . . . . . . 7
4.6. Endorser in I2NSF . . . . . . . . . . . . . . . . . . . . 7
5. Data Model of I2NSF Remote Attestation . . . . . . . . . . . 7
5.1. I2NSF Remote Attestation Evidence Interface . . . . . . . 7
5.1.1. YANG Tree Diagram of I2NSF Remote Attestation Evidence
Interface . . . . . . . . . . . . . . . . . . . . . . 8
5.1.2. YANG Data Model of I2NSF Remote Attestation
Interface . . . . . . . . . . . . . . . . . . . . . . 14
5.2. I2NSF Remote Attestation Reference Value Interface . . . 22
5.2.1. YANG Tree Diagram of I2NSF Remote Attestation Reference
Value Interface . . . . . . . . . . . . . . . . . . . 22
5.2.2. YANG Data Model of I2NSF Remote Attestation Reference
Value Interface . . . . . . . . . . . . . . . . . . . 23
5.3. I2NSF Remote Attestation Result Interface . . . . . . . . 28
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 28
7. Security Considerations . . . . . . . . . . . . . . . . . . . 29
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.1. Normative Reference . . . . . . . . . . . . . . . . . . . 29
8.2. Informative Reference . . . . . . . . . . . . . . . . . . 31
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31
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1. Introduction
In terms of implementation, NSFs are usually deployed in remote
scenarios, where it is hard to guarantee if the deploy environment is
secure and the NSFs are properly deployed. If the deploy environment
or the NSF is compromised, the behavior and the feedback of NSFs
cannot be trusted.
Remote attestation procedure [I-D.ietf-rats-architecture] provides an
efficient mechanism that a verifier likes Network Operator Mgmt
System could appraise if the NSFs and the basic platforms are
trusted. The general remote attestation procedure has been defined
by RATs working group, however specific interfaces and
implementations still need to be determined in I2NSF. This document
aims to create a unified remote attestation architecture for I2NSF to
enable remote attestation of NSF.
This document follows the definition of I2NSF framework[RFC8329] and
also could be treated as a usecase of RATs. In detail, this document
refers to the definition of RATs architecture to add new remote
attestation components in I2NSF. This document refers to
[I-D.ietf-rats-yang-tpm-charra] and
[I-D.ietf-rats-tpm-based-network-device-attest]to define I2NSF YANG
model for evidence in TPM-based platform. This document refers to
[I-D.ietf-rats-eat] to define I2NSF YANG model for evidence in TEE-
based platform. This document refers to [I-D.ietf-rats-ar4si] to
defien I2NSF YANG model for attestation result.
2. Terminology
2.1. Terms
RATs: Remote Attestation Procedure
RoT: Root of Trust
TPM: Trusted platform module
TEE: Trust Execution Environment
RVP: Reference Value Provider
2.2. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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3. Scope and Motivation
3.1. Scope
The scope of this document focuses on the architecture and expanded
interfaces of NSF remote attestation in I2NSF. The details of how to
implement measurement or how to collect remote attestation evidence
is out of scope.
3.2. Motivation
The architecture of I2NSF aims to provide network security functions
to network users. Usually the NSFs are in remote environment and the
platforms to deploy these NSFs may not be trusted. As a consequence
this will bring several potential threats to I2NSF framework, some
examples are shown below. The first threat is malfunction of NSF.
The inappropriate deployment of NSF or the defective platform in
where runs NSF will affect the behaviour of NSF directly. The second
threat is the leak of digital asset like policy rules and security
intelligence which is provided by the Network Operator Mgmt System.
Consider a secuiry company provides NSF in where contains lots of
policy rules such as DDoS prevention, traffic filter, AI module, etc.
If the platform who carrys the NSF is malicious, it could steal this
digital asset and provide to other rivals or attackers. The third
threat is the potential spoofing or penetration attack to the I2NSF
framework. The attackers in NSF platfom could disturb the action of
NSF, and feedback the fake notification or even penetrate into
Network Operator Mgmt System.
The solution of these kinds of threats is also straight, which is
using remote attestation to make sure the remote platform is trusted
and the NSFs are well deployed. While it is true that any
environment is vulnerable to malicious activity with full physical
access (and this is obviously beyond the scope of this document), the
application of remote attestation raises the degree of physical
control necessary to perform an untraceable malicious modification of
that environment.
When designing remote attestation in I2NSF, three aspects need to be
considered. First, determine the remote attestation architecture of
I2NSF. Second, refer to the appropriate specifications defined in
RATs to create I2NSF remote attestation interfaces and YANG data
models. Third, cover the heterogeneity architecture of specific
trusted hardware like TPM and TEE.
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4. Information Model
4.1. Architecture of I2NSF Remote Attestation
As shown in figure 1 is the remote attestation architecture in I2NSF.
In order to fit into the I2NSF framework, this is not a typical
background check model or passport model mentioned in RATs
architecture. In this figure, the relevant interfaces are I2NSF
remote attestation evidence interface, I2NSF remote attestation
registration interface and I2NSF remote attestation result interface.
+------------+ +------------+
| I2NSF User | +----+ Endorser |
+-+-+------+-+ | +------------+
| Relying| |
| Party | |
+-+------+ |
| Attestation Result |
| Interface |
| +--------------+
+---+------+---+ +--------------+
| Network | | |
| Operator +--------------+ Developer's |
| Mgmt System | Reference | Mgmt System |
+-+----------+-+ Value +-+----------+-+
| | Interface | Reference|
| Verifier | | Value |
| | | Provider |
+----+-----+ +----------+
+---------------------+
| Evidence Interface |
+------+-------+ +------+-------+
| NSF1 + | NSFn |
+--------------+------+--------------+
| Platform |
+-------------+--------+-------------+
| RoT |
+--------+
Figure 1: Architecture of Remote Attestation of I2NSF
In physical environment, NSFs exist as applications. In
virtualization environment, the level-of-assurence of NFV is
separated as two components: hardware and virtualization platform,
VNF sotftware package[NFV-SEC-018]. When using this concept of VNF
sotfware package in I2NSF, the granularity of NSF in virtualization
environment is NSF and the VM it loaded in. As a result, the trust
chain in virtualization environment would be RoT->virtualization
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layer->VM and NSF. And the trust chain in physical environment would
be RoT->physical platform->NSF. Hence, we define the granularity of
remote attestation in I2NSF as in Figure 2. The remote attestation
procedure in I2NSF could challenge RoT, Platform and NSFs separately.
+------+ +------+ +------+
| (VM) | | (VM) | | (VM) |
| NSF1 | | NSF2 | | NSFn |
+--+---+ +--+---+ +--+---+
| | |
+--+----------+----------+----+
| (virtualization)Platform |
+-------------+---------------+
|
+--+--+
| RoT |
+-----+
Figure 2: granularity of remote attestation in I2NSF
4.2. Root of Trust in I2NSF
Root of Trust is a hardware-based component that could provide
endorsement information and relevant functions that cannot be stolen,
tampered, or repudiated. RoT must be deployed in the basic hardware
platform of NSF. Technologies like [TCGRoT] and [TEE] could act as
RoT.
The architecture of specific RoT is out of scope of this document.
But in order to depict RoT more clearly, the following segment uses
TPM [tpm12][tpm20] as an example to explain how RoT works. TPM keeps
an EK(Endorsement Key) to identify its identity. EK is an asymmetric
root key pair, which never exposes its secret key to public. TPM
derives certain AIKs(Attestation Identity Key) from EK to avoid the
exposure of TPM's real identity(EK) during remote attestation. In
the booting period, the TPM will record the Hash of measurement of
bootloader, OS kernel and applications to a series of PCRs (Platform
Configuration Registers). The value in PCRs can only be extended and
cannot be tampered. If a remote attestation procedure is initiated,
the PCR value will be signed by AIK and send to the verifier for
attestation. The verifier then transfer the attestation result to
Relying party for final decision.
4.3. Verifier in I2NSF
Verifier is deployed in Network Operator Mgmt System. Verifier is in
charge of receiving attestation evidence from NSFs. Also, Verifier
receives reference value from Developer's Mgmt system as benchmark.
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4.4. Reference Value Provider in I2NSF
Reference Value Provider (RVP) brings the reference value of NSF
remote attestation to Network Operation Mgmt System. In some
conditions, the RVP could be some other venders like a blockchain, a
third party security provider. So the RVP component may be an
interface that receive RVP form the third party. Or, the RVP could
be deployed in Developer's Mgmt System. The reference value will be
conveyed to Network Operator Mgmt System as the benchmark when
verifying remote attestation evidence from attester. When the
reference value needs to be collected by third party, the Reference
Value Interface or other out-of-band methods in Developer's Mgmt
System could be used.
4.5. Relying Party in I2NSF
Relying Party is deployed in I2NSF User. Relying Party is in charge
of receiving attestation result from Verifier and generate user
friendly policies to NSF User. The Relying Party does not have to
know the detail of remote attestation evidence and could only focus
on the final attestation result and making policies.
4.6. Endorser in I2NSF
Endorser provides the endorsement of RoT. And the verifier could use
Endorser to verify the evidence information from NSF. For example,
both EK and AIK in TPM are endorsed by Endorser. The communication
between RoT and Endorser is based on specific RoT hardware, and
usually has been setup during manufactureing. The Network Operator
Mgmt System also needs to communicate with Endorser to get the
endorsement of RoT before appraising attestation evidence.
5. Data Model of I2NSF Remote Attestation
The following section depicts the YANG tree diagram and YANG data
model of I2NSF remote attestation interfaces.
5.1. I2NSF Remote Attestation Evidence Interface
Evidence interface focuses on the remote attestation evidence
information between NSF and Network Operator Mgmt system. This
interface defines notification and RPC for RoT, platform and NSFs.
At present, the RoT type has two categories, one is TPM-based and the
other is TEE-based like TrustZone and SGX[SGX]. The TPM-based RoT is
split into TPM12 and TPM20 versions. When design this interface with
TPM-based RoT, this document refers to the existing
document[I-D.ietf-rats-yang-tpm-charra] to avoid unnecessary
alignment work. And about the TEE-based RoT, this document refers to
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the EAT document[I-D.ietf-rats-eat] and uses binary format to express
JWT[RFC7519]or CWT [RFC8392] in YANG data model.
In order to decouple the remote attestation result to NSF
granularity, the following table defines the mapping between differnt
layers. In the TPM-based remote attestation, the PCRs are arranged
by specific purpose[I-D.ietf-rats-tpm-based-network-device-attest].
PCR 0-10 are responsible for the platform related remote attestation.
PCR 11-31 are responsible for the NSF remote attestation. If the
platform is a virtual machine architecture, PCR 11-31 will be
responsible for each virtual machine and its NSF. If the platform is
a physical machines architecture, PCR 10-31 will be responsible for
each NSF functions. The EAT-based platform uses Token to realize
different remote attestation layers. EAT SYS Token and EAT NSF TOKEN
are responsible for platform and NSF respectively.
+--------+-------------+------------+
| | TPM-based | EAT-based |
+------- +-------------+------------+
| RoT | Device Name | Device ID |
| | TPM Name | |
+--------+-------------+------------+
| | Boot event | |
| | log | EAT SYS |
|Platform|-------------| Token |
| | IMA-List | |
| | Sytem File | |
| | PCR 0-10 | |
+--------+-------------+------------+
| | IMA-list | EAT NSF |
| NSF | NSF File | Token |
| | PCR 10-31 | |
+--------+-------------+------------+
Figure 3: the mapping between different RoTs
5.1.1. YANG Tree Diagram of I2NSF Remote Attestation Evidence Interface
The YANG tree of i2nsf remote attestation evidence interface is shown
below.
module: ietf-i2nsf-remote-attestation-evidence
+--rw nsf-pcr-set {tpm:tpms}?
| +--rw nsf-name? nsf-name
| +--rw pcr-index? tpm:pcr
+--rw eat-set {TEE}?
+--rw algorithm? enumeration
+--rw cwt-uwt-choose? int32
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rpcs:
+---x nsf-challenge-response
| +---w input
| | +---w nsf-name? nsf-name
| | +---w token? binary
| | +---w nonce? uint32
| +--ro output
| +--ro (RoT-type)?
| +--:(TPM12) {TPM12}?
| | +--ro tpm12-ra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro up-time? uint32
| | +--ro TPM_QUOTE2? binary
| +--:(TPM20) {TPM20}?
| | +--ro tpm20-ra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro TPMS_QUOTE_INFO binary
| | +--ro quote-signature? binary
| | +--ro up-time? uint32
| | +--ro unsigned-pcr-values* []
| | +--ro tpm20-hash-algo? identityref
| | +--ro pcr-values* [pcr-index]
| | +--ro pcr-index pcr
| | +--ro pcr-value? binary
| +--:(TEE)
| +--ro header-NSF? binary
| +--ro payload-NSF? binary
| +--ro signature-NSF? binary
+---x platform-challenge-response
| +---w input
| | +---w token? binary
| | +---w nsf-name? nsf-name
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| | +---w nonce? int32
| +--ro output
| +--ro (RoT-type)?
| +--:(TPM12) {TPM12}?
| | +--ro tpm12-pra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro bios-event-entry* [event-number]
| | | +--ro event-number uint32
| | | +--ro event-type? uint32
| | | +--ro pcr-index? pcr
| | | +--ro digest-list* [hash-alog]
| | | | +--ro hash-algo? identityref
| | | | +--ro digest* binary
| | | +--ro event-size? uint32
| | | +--ro event-data* uint8
| | +--ro up-time? uint32
| | +--ro TPM_QUOTE2? binary
| +--:(TPM20) {TPM20}?
| | +--ro tpm2-pra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro bios-event-entry* [event-number]
| | | +--ro event-number uint32
| | | +--ro event-type? uint32
| | | +--ro pcr-index? pcr
| | | +--ro digest-list* [hash-alog]
| | | | +--ro hash-algo? identityref
| | | | +--ro digest* binary
| | | +--ro event-size? uint32
| | | +--ro event-data* uint8
| | +--ro TPMS_QUOTE_INFO binary
| | +--ro quote-signature? binary
| | +--ro up-time? uint32
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| | +--ro unsigned-pcr-values* []
| | +--ro tpm20-hash-algo? identityref
| | +--ro pcr-values* [pcr-index]
| | +--ro pcr-index pcr
| | +--ro pcr-value? binary
| +--:(TEE) {TEE}?
| +--ro header-platform? binary
| +--ro payload-platform? binary
| +--ro signature-platform? binary
+---x RoT-challenge-response
+---w input
| +---w token? binary
| +---w nsf-name? nsf-name
| +---w nonce? int32
+--ro output
+--ro (RoT-type)?
+--:(TPM12)
| +--ro rot-tpm12 {TPM12}?
| +--ro rot-name? ->
/tpm:rats-support-structures/tpms/tpm/
certificates/certificate/name
| +--ro certificate-name certificate-name-ref
| +--ro tpm12-hash-algo? identityref
+--:(TPM20) {TPM20}?
| +--ro rot-tpm20
| +--ro rot-name? ->
/tpm:rats-support-structures/tpms/tpm/
certificates/certificate/name
| +--ro certificate-name certificate-name-ref
| +--ro tpm20-hash-algo? identityref
+--:(TEE-general) {TEE}?
+--ro TEE-UEID? binary
notifications:
+---n NSF-remote-attestation-event
| +--ro event-description? string
| +--ro acquisition-method? identityref
| +--ro emission-type? identityref
| +--ro dampening-type? identityref
| +--ro user string
| +--ro group* string
| +--ro ip-address inet:ip-address
| +--ro authentication? identityref
| +--ro message? string
| +--ro vendor-name? string
| +--ro nsf-name? union
| +--ro severity? severity
| +--ro (RoT-type)?
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| +--:(TPM12) {TPM12}?
| | +--ro tpm12-ra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro up-time? uint32
| | +--ro TPM_QUOTE2? binary
| +--:(TPM20) {TPM20}?
| | +--ro tpm20-ra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro TPMS_QUOTE_INFO binary
| | +--ro quote-signature? binary
| | +--ro up-time? uint32
| | +--ro unsigned-pcr-values* []
| | +--ro tpm20-hash-algo? identityref
| | +--ro pcr-values* [pcr-index]
| | +--ro pcr-index pcr
| | +--ro pcr-value? binary
| +--:(TEE)
| +--ro header-NSF? binary
| +--ro payload-NSF? binary
| +--ro signature-NSF? binary
+---n Platform-remote-attestation-event
| +--ro event-description? string
| +--ro acquisition-method? identityref
| +--ro emission-type? identityref
| +--ro dampening-type? identityref
| +--ro user string
| +--ro group* string
| +--ro ip-address inet:ip-address
| +--ro authentication? identityref
| +--ro message? string
| +--ro vendor-name? string
| +--ro nsf-name? union
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| +--ro severity? severity
| +--ro (RoT-type)?
| +--:(TPM12) {TPM12}?
| | +--ro tpm12-pra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro bios-event-entry* [event-number]
| | | +--ro event-number uint32
| | | +--ro event-type? uint32
| | | +--ro pcr-index? pcr
| | | +--ro digest-list* [hash-alog]
| | | | +--ro hash-algo? identityref
| | | | +--ro digest* binary
| | | +--ro event-size? uint32
| | | +--ro event-data* uint8
| | +--ro up-time? uint32
| | +--ro TPM_QUOTE2? binary
| +--:(TPM20) {TPM20}?
| | +--ro tpm2-pra
| | +--ro event-number? uint64
| | +--ro ima-template? string
| | +--ro filename-hint? string
| | +--ro filedata-hash? binary
| | +--ro filedata-hash-algorithm? string
| | +--ro template-hash-algorithm? string
| | +--ro template-hash? binary
| | +--ro pcr-index? pcr
| | +--ro signature? binary
| | +--ro bios-event-entry* [event-number]
| | | +--ro event-number uint32
| | | +--ro event-type? uint32
| | | +--ro pcr-index? pcr
| | | +--ro digest-list* [hash-alog]
| | | | +--ro hash-algo? identityref
| | | | +--ro digest* binary
| | | +--ro event-size? uint32
| | | +--ro event-data* uint8
| | +--ro TPMS_QUOTE_INFO binary
| | +--ro quote-signature? binary
| | +--ro up-time? uint32
| | +--ro unsigned-pcr-values* []
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| | +--ro tpm20-hash-algo? identityref
| | +--ro pcr-values* [pcr-index]
| | +--ro pcr-index pcr
| | +--ro pcr-value? binary
| +--:(TEE) {TEE}?
| +--ro header-platform? binary
| +--ro payload-platform? binary
| +--ro signature-platform? binary
+---n RoT-remote-attestation-event
+--ro event-description? string
+--ro acquisition-method? identityref
+--ro emission-type? identityref
+--ro dampening-type? identityref
+--ro user string
+--ro group* string
+--ro ip-address inet:ip-address
+--ro authentication? identityref
+--ro message? string
+--ro vendor-name? string
+--ro nsf-name? union
+--ro severity? severity
+--ro (RoT-type)?
+--:(TPM12)
| +--ro rot-tpm12 {TPM12}?
| +--ro rot-name? ->
/tpm:rats-support-structures/tpms/tpm/
certificates/certificate/name
| +--ro certificate-name certificate-name-ref
| +--ro tpm12-hash-algo? identityref
+--:(TPM20) {TPM20}?
| +--ro rot-tpm20
| +--ro rot-name? ->
/tpm:rats-support-structures/tpms/tpm/
certificates/certificate/name
| +--ro certificate-name certificate-name-ref
| +--ro tpm20-hash-algo? identityref
+--:(TEE-general) {TEE}?
+--ro TEE-UEID? binary
5.1.2. YANG Data Model of I2NSF Remote Attestation Interface
The YANG Model of I2NSF Remote Attestation Evidence Interface is
shown below.
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module ietf-i2nsf-remote-attestation-evidence{
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-i2nsf-remote-
attestation-evidence";
prefix
nsfra;
import ietf-i2nsf-nsf-monitoring{
prefix nsfmi;
reference
"Section 9 of draft-ietf-i2nsf-nsf-facing-interface";
}
import ietf-tpm-remote-attestation{
prefix tpm;
}
import ietf-inet-types{
prefix inet;
reference
"section 4 of RFC 6991";
}
organization
"IETF I2NSF (Interface to Network Security Functions)
Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/i2nsf>
WG List: <mailto:i2nsf@ietf.org>
Editor: Penglin Yang
<mailto:yangpenglin@chinamobile.com>";
description
"This module is a YANG module for I2NSF Remote
Attestation Interface.";
feature TPM12{
description
"This device is for TPM12 remote attestation";
}
feature TPM20{
description
"This device is for TPM20 remote attestation";
}
feature TEE{
description
"This device is for general TEE remote attestation";
}
typedef nsf-name{
type union{
type string;
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type inet:ip-address-no-zone;
}
description
"nsf-name for remote attestation";
}
identity RoT-type{
description
"RoT have different types, like TPM, TEE, etc.";
}
identity TPM12{
base RoT-type;
description
"RoT type is TPM1.2";
}
identity TPM20{
base RoT-type;
description
"RoT type is TPM2.0";
}
identity TEE{
base RoT-type;
description
"RoT type is TEE";
}
identity cwt{
description
"cbor web token for remote attestation";
}
identity jwt{
description
"json web token for remote attestation";
}
identity nsf-name{
description
"nsf name";
}
grouping nsf-remote-attestation{
description
"This grouping is for certain nsf's remote attestation result.";
choice RoT-type{
case TPM12{
if-feature "TPM12";
description
"The filename hint of IMA log item is NSF name. The range
of PCR index is defined as 11~32.";
container tpm12-ra{
uses tpm:ima-event;
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uses tpm:tpm12-attestation;
}
}
case TPM20{
if-feature "TPM20";
container tpm20-ra{
uses tpm:ima-event;
uses tpm:tpm20-attestation;
}
}
case TEE{
description
"EAT for NSF remote attestation";
leaf header-NSF{
type binary;
}
leaf payload-NSF{
type binary;
}
leaf signature-NSF{
type binary;
}
}
}
}
grouping platform-remote-attestation{
description
"this item is for platform remote attestation";
choice RoT-type{
case TPM12{
if-feature "TPM12";
container tpm12-pra{
uses tpm:ima-event;
uses tpm:bios-event-log;
uses tpm:tpm12-attestation;
}
}
case TPM20{
if-feature "TPM20";
container tpm20-pra{
uses tpm:ima-event;
uses tpm:bios-event-log;
uses tpm:tpm20-attestation;
}
}
case TEE{
if-feature "TEE";
description
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"EAT for Platform Remote Attestation";
leaf header-platform{
type binary;
}
leaf payload-platform{
type binary;
}
leaf signature-platform{
type binary;
}
}
}
}
grouping RoT-remote-attestation{
description
"this item is for the identity of platform and RoT";
choice RoT-type{
case TPM12{
container rot-tpm12{
if-feature "TPM12";
description
"the identity of TPM could be represented by
TPM-name and certificate";
leaf rot-name{
type leafref {
path "/tpm:rats-support-structures/tpm:tpms/tpm:tpm"
+ "/tpm:certificates/tpm:certificate/tpm:name";
}
}
uses tpm:certificate-name-ref;
uses tpm:tpm12-hash-algo;
}
}
case TPM20{
if-feature "TPM20";
description
"the identity of TPM could be represented
by TPM-name and certificate";
container rot-tpm20{
leaf rot-name{
type leafref {
path "/tpm:rats-support-structures/tpm:tpms/tpm:tpm"
+ "/tpm:certificates/tpm:certificate/tpm:name";
}
}
uses tpm:certificate-name-ref;
uses tpm:tpm20-hash-algo;
}
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}
case TEE-general{
if-feature "TEE";
leaf TEE-UEID{
type binary;
}
}
}
}
notification NSF-remote-attestation-event{
description
"Event that triggered the NSF remote attestation
will use this notification";
leaf event-description{
description
"describe the reason why notification was triggered";
type string;
}
uses nsfmi:characteristics;
uses nsfmi:i2nsf-system-event-type-content;
uses nsfmi:common-monitoring-data;
uses nsf-remote-attestation;
}
notification Platform-remote-attestation-event{
description
"Event that triggered the platform remote attestation
will use this notification ";
leaf event-description{
description
"describe why this notification was triggered";
type string;
}
uses nsfmi:characteristics;
uses nsfmi:i2nsf-system-event-type-content;
uses nsfmi:common-monitoring-data;
uses platform-remote-attestation;
}
notification RoT-remote-attestation-event{
description
"Event that triggered the rot remote attestation
will use this notification";
leaf event-description{
description
"describe why this notification was triggered";
type string;
}
uses nsfmi:characteristics;
uses nsfmi:i2nsf-system-event-type-content;
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uses nsfmi:common-monitoring-data;
uses RoT-remote-attestation;
}
//token in RPC is for specify the identity of RPC caller. //
grouping token{
description
"this token is for identify rpc caller. How to define
this token, oauth, JWT, or other? Or not necessary, TBD";
leaf token{
type binary;
}
}
rpc nsf-challenge-response{
description
"this is the unified rpc for nsf remote attestation";
input{
leaf nsf-name{
type nsf-name;
}
uses token;
leaf nonce{
type uint32;
}
}
output{
uses nsf-remote-attestation;
}
}
rpc platform-challenge-response{
description
"this rpc is for platform challenge ";
input{
uses token;
leaf nsf-name{
type nsf-name;
}
leaf nonce{
type int32;
}
}
output{
uses platform-remote-attestation;
}
}
rpc RoT-challenge-response{
input{
uses token;
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leaf nsf-name{
type nsf-name;
}
leaf nonce{
type int32;
}
}
output{
uses RoT-remote-attestation;
}
}
//***********************************************//
// configuration about PCR and NSF set. //
//***********************************************//
container nsf-pcr-set{
description
"this container is used for NSF-name, IMA log and
PCR index setting. NSF-name needs to be set as the
IMA item filename-hint, the pcr value need to be
set as the IMA pcr index.";
if-feature "tpm:tpms";
leaf nsf-name{
type nsf-name;
}
leaf pcr-index{
type tpm:pcr;
}
}
//***********************************************//
// configuration about EAT set. //
//***********************************************//
container eat-set{
description
"this container is for NSF-name set in EAT environment";
if-feature "TEE";
leaf algorithm{
description
"set the signing algorithm for generating EAT";
type enumeration{
enum HS256;//hmac with sha256
enum RS256;//rsa with sha256
}
}
leaf cwt-uwt-choose{
type int32;
description
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"0 is cwt, 1 is uccs, 2 is jwt";
}
}
}
5.2. I2NSF Remote Attestation Reference Value Interface
The reference value of a NSF needs to be conveyed by I2NSF remote
attestation reference value interface. The interface works between
Network Operator Mgmt System and Developer's Management System.
5.2.1. YANG Tree Diagram of I2NSF Remote Attestation Reference Value
Interface
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module: ietf-i2nsf-remote-attestation-reference-value
+--rw nsf-tpm-reference-value-registration
| +--rw nsf-name nsf-name
| +--rw ima-template? string
| +--rw nsf-hash? binary
| +--rw nsf-hash-algorithm? string
| +--rw pcr-index? pcr
+--rw nsf-tee-reference-value-registration
| +--rw nsf-name nsf-name
| +--rw header-NSF? binary
| +--rw payload-NSF? binary
| +--rw signature-NSF? binary
+--rw rot-reference-value-registration
| +--rw (RoT-type)?
| +--:(TPM12) {TPM12}?
| | +--rw rot-tm12
| | +--rw rot-tpm12-name? string
| | +--rw certificate-name certificate-name-ref
| | +--rw tpm12-hash-algo? identityref
| +--:(TPM20) {TPM20}?
| | +--rw rot-tpm20
| | +--rw rot-tpm20-name? string
| | +--rw certificate-name certificate-name-ref
| | +--rw tpm20-hash-algo? identityref
| +--:(TEE) {TEE}?
| +--rw TEE-UEID? binary
+--rw platform-tpm-reference-value-registration
| +--rw platform-name string
| +--rw ima-template? string
| +--rw nsf-hash? binary
| +--rw nsf-hash-algorithm? string
| +--rw pcr-index? pcr
+--rw platform-tee-remote-attestation-reference-value
+--rw platform-name nsf-name
+--rw header-NSF? binary
+--rw payload-NSF? binary
+--rw signature-NSF? binary
5.2.2. YANG Data Model of I2NSF Remote Attestation Reference Value
Interface
The YANG Model of I2NSF remote attestation reference value interface
is shown below. The registration information will refer to the
measurement logs and algorithms of remote attestation. The log
infomation contains all the information needed by Network Operator
Mgmt System to apparaise attester's evidence.
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module ietf-i2nsf-remote-attestation-reference-value {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-i2nsf-remote-
attestation-reference-value";
prefix
nsfrarv;
import ietf-tpm-remote-attestation{
prefix tpm;
}
import ietf-inet-types{
prefix inet;
}
organization
"IETF I2NSF (Interface to Network Security Functions)
Working Group";
contact
"WG Web: <http://tools.ietf.org/wg/i2nsf>
WG List: <mailto:i2nsf@ietf.org>
Editor: Penglin Yang
<mailto:yangpenglin@chinamobile.com>";
description
"This module is a YANG module for I2NSF NSF remote
attestation reference value.";
identity RoT-type{
description
"RoT have different types, like TPM, TEE, etc.";
}
identity TPM12{
base RoT-type;
description
"RoT type is TPM1.2";
}
identity TPM20{
base RoT-type;
description
"RoT type is TPM2.0";
}
identity TEE{
base RoT-type;
description
"RoT type is TEE general";
}
feature TPM12{
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description
"tpm 1.2 version";
}
feature TPM20{
description
"tpm 2.0 version";
}
feature TEE{
description
"TEE version";
}
typedef nsf-name{
type union{
type string;
type inet:ip-address-no-zone;
}
description
"nsf-name for regular expression";
}
typedef pcr{
type uint8{
range "0..31";
}
}
container nsf-tpm-reference-value-registration{
description
"the reference value is for nsf in tpm20 platform";
leaf nsf-name{
type nsf-name;
mandatory true;
description
"The name of nsf";
}
leaf ima-template {
type string;
description
"Name of the template used for event logs
for e.g. ima, ima-ng, ima-sig";
}
leaf nsf-hash {
type binary;
description
"Hash of nsf file/image";
}
leaf nsf-hash-algorithm {
type string;
description
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"Algorithm used for filedata-hash";
}
leaf pcr-index {
type pcr;
description
"Defines the PCR index that stores this nsf";
}
}
container nsf-tee-reference-value-registration{
description
"the reference value is for nsf in TEE platform";
leaf nsf-name{
type nsf-name;
mandatory true;
description
"The name of nsf";
}
leaf header-NSF{
type binary;
}
leaf payload-NSF{
type binary;
}
leaf signature-NSF{
type binary;
}
}
container rot-reference-value-registration{
description
"this container is for root of trust reference value";
choice RoT-type{
case TPM12{
if-feature "TPM12";
description
"the identity of TPM could be represented by
TPM-name and certificate";
container rot-tm12{
leaf rot-tpm12-name{
type string;
}
uses tpm:certificate-name-ref;
uses tpm:tpm12-hash-algo;
}
}
case TPM20{
if-feature "TPM20";
description
"the identity of TPM could be represented by
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TPM-name and certificate";
container rot-tpm20{
leaf rot-tpm20-name{
type string;
}
uses tpm:certificate-name-ref;
uses tpm:tpm20-hash-algo;
}
}
case TEE{
if-feature "TEE";
leaf TEE-UEID{
//provide a UEID to identify TEE
type binary;
}
}
}
}
container platform-tpm-reference-value-registration{
description
"this container is for platform reference value";
leaf platform-name{
type string;
mandatory true;
description
"The name of nsf";
}
leaf ima-template {
type string;
description
"Name of the template used for event logs
for e.g. ima, ima-ng, ima-sig";
}
leaf nsf-hash {
type binary;
description
"Hash of nsf file/image";
}
leaf nsf-hash-algorithm {
type string;
description
"Algorithm used for filedata-hash";
}
leaf pcr-index {
type pcr;
description
"Defines the PCR index that stores this nsf";
}
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}
container platform-tee-remote-attestation-reference-value{
description
"the reference value is for platform in TEE platform";
leaf platform-name{
type nsf-name;
mandatory true;
description
"The name of nsf";
}
leaf header-NSF{
type binary;
}
leaf payload-NSF{
type binary;
}
leaf signature-NSF{
type binary;
}
}
}
5.3. I2NSF Remote Attestation Result Interface
This interface is used to transfer attestation result from Verifier
to Network User. The definition and data format refer to
[I-D.ietf-rats-ar4si], TBD.
6. IANA Considerations
This document requests IANA to register the following URI in the
"IETF XML Registry" RFC 3688 [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-i2nsf-remote-attestation-
evidence Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
URI: urn:ietf:params:xml:ns:yang:ietf-i2nsf-remote-attestation-
reference-value Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
This document requests IANA to register the following YANG module in
the "YANG Module Names" registry RFC 7950 [RFC7950] RFC 8525
[RFC8525]:
Name: ietf-i2nsf-remote-attestation-evidence-interface
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Namespace: urn:ietf:params:xml:ns:yang:ietf-i2nsf-remote-
attestation-evidence
Prefix: nsfra
Reference: RFC XXXX
Name: ietf-i2nsf-remote-attestation-reference-value-interface
Namespace: urn:ietf:params:xml:ns:yang:ietf-i2nsf-remote-
attestation-reference-value
Prefix: nsfteri
Reference: RFC XXXX
7. Security Considerations
This document introduces the architecture of I2NSF remote attestation
and designs related interfaces. Different RoT architectures have
different trust ability and different appearance. Network Operator
Mgmt System will determine if it will trust these remote attestation
results by customized policy rules. The I2NSF remote attestation
interfaces need to be protected by secure channel when transmission
occurs. Meanwhile, the remote attestation results in interfaces are
protected by their own mechanisms like TPM signature or token.
8. References
8.1. Normative Reference
[I-D.ietf-rats-ar4si]
Voit, E., Birkholz, H., Hardjono, T., Fossati, T., and V.
Scarlata, "Attestation Results for Secure Interactions",
Work in Progress, Internet-Draft, draft-ietf-rats-ar4si-
02, 7 March 2022, <https://www.ietf.org/archive/id/draft-
ietf-rats-ar4si-02.txt>.
[I-D.ietf-rats-architecture]
Birkholz, H., Thaler, D., Richardson, M., Smith, N., and
W. Pan, "Remote Attestation Procedures Architecture", Work
in Progress, Internet-Draft, draft-ietf-rats-architecture-
17, 1 June 2022, <https://www.ietf.org/archive/id/draft-
ietf-rats-architecture-17.txt>.
[I-D.ietf-rats-eat]
Lundblade, L., Mandyam, G., and J. O'Donoghue, "The Entity
Attestation Token (EAT)", Work in Progress, Internet-
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Draft, draft-ietf-rats-eat-13, 20 May 2022,
<https://www.ietf.org/archive/id/draft-ietf-rats-eat-
13.txt>.
[I-D.ietf-rats-tpm-based-network-device-attest]
Fedorkow, G., Voit, E., and J. Fitzgerald-McKay, "TPM-
based Network Device Remote Integrity Verification", Work
in Progress, Internet-Draft, draft-ietf-rats-tpm-based-
network-device-attest-14, 22 March 2022,
<https://www.ietf.org/archive/id/draft-ietf-rats-tpm-
based-network-device-attest-14.txt>.
[I-D.ietf-rats-yang-tpm-charra]
Birkholz, H., Eckel, M., Bhandari, S., Voit, E., Sulzen,
B., (Frank), L. X., Laffey, T., and G. C. Fedorkow, "A
YANG Data Model for Challenge-Response-based Remote
Attestation Procedures using TPMs", Work in Progress,
Internet-Draft, draft-ietf-rats-yang-tpm-charra-21, 18 May
2022, <https://www.ietf.org/archive/id/draft-ietf-rats-
yang-tpm-charra-21.txt>.
[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>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/info/rfc7519>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
[RFC8329] Lopez, D., Lopez, E., Dunbar, L., Strassner, J., and R.
Kumar, "Framework for Interface to Network Security
Functions", RFC 8329, DOI 10.17487/RFC8329, February 2018,
<https://www.rfc-editor.org/info/rfc8329>.
[RFC8392] Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig,
"CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392,
May 2018, <https://www.rfc-editor.org/info/rfc8392>.
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[RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K.,
and R. Wilton, "YANG Library", RFC 8525,
DOI 10.17487/RFC8525, March 2019,
<https://www.rfc-editor.org/info/rfc8525>.
8.2. Informative Reference
[NFV-SEC-018]
ETSI, "Report on NFV Remote Attestation Architecture",
November 2019, <https://www.etsi.org/deliver/etsi_gr/NFV-
SEC/001_099/018/01.01.01_60/gr_NFV-SEC018v010101p.pdf>.
[SGX] Intel, "Overview of Intel Software Guard Extension", June
2016,
<https://www.intel.com/content/www/us/en/developer/tools/
software-guard-extensions/overview.html>.
[TCGRoT] Trust Computing Group, "DRAFT: TCG Roots of Trust
Specification", October 2018,
<https://trustedcomputinggroup.org/wp-content/uploads/
TCG_Roots_of_Trust_Specification_v0p20_PUBLIC_REVIEW.pdf>.
[TEE] Global Platform Technology, "Global Platform Technology
TEE System Architecture Version 1.2", December 2018,
<https://globalplatform.org/specs-library/tee-system-
architecture-v1-2/>.
[tpm12] Trusted Computing Group, "TPM Main Specification Level 2
Version 1.2, Revision 116", March 2011,
<https://trustedcomputinggroup.org/resource/tpm-main-
specification/>.
[tpm20] Trusted Computing Group, "Trusted Platform Module Library
Specification, Family "2.0", Level 00, Revision 01.59",
November 2019,
<https://trustedcomputinggroup.org/resource/tpm-library-
specification/>.
Authors' Addresses
Penglin Yang
China Mobile
32 Xuanwumen West Street, Xicheng District
Beijing
100053
China
Email: yangpenglin@chinamobile.com
Yang, et al. Expires 8 December 2022 [Page 31]
Internet-Draft I2NSF Remote Attestation Interface DM June 2022
Meiling Chen
China Mobile
32 Xuanwumen West Street, Xicheng District
Beijing
100053
China
Email: chenmeiling@chinamobile.com
Li Su
China Mobile
32 Xuanwumen West Street, Xicheng District
Beijing
100053
China
Email: suli@chinamobile.com
Diego Lopiz
Telefonica
Email: diego.r.lopez@telefonica.com
Jaehoon Paul Jeong
Sungkyunkwan University
Email: jaehoon.paul@gmail.com
Linda Dunbar
Futurewei
Email: linda.dunbar@futurewei.com
Yang, et al. Expires 8 December 2022 [Page 32]
