Internet DRAFT - draft-dong-sacm-nid-infra-security-baseline
draft-dong-sacm-nid-infra-security-baseline
Network Working Group Y. Dong
Internet-Draft L. Xia
Intended status: Standards Track Huawei
Expires: November 26, 2018 May 25, 2018
The Data Model of Network Infrastructure Device Infrastructure Layer
Security Baseline
draft-dong-sacm-nid-infra-security-baseline-01
Abstract
This document is one of the companion documents which describes the
infrastructure layer security baseline YANG output for network
infrastructure devices. The infrastructure layer security baseline
covers the security functions to secure the device itself, and the
fundamental security capabilities provided by the device to the upper
layer applications. In this specific document, the integrity
measurement, cryptography algorithms, key management, and certificate
management are sorted out to generate the data model.
Status of This Memo
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This Internet-Draft will expire on November 26, 2018.
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to this document. Code Components extracted from this document must
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Infrastructure layer security baseline . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Key Words . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Definition of Terms . . . . . . . . . . . . . . . . . . . 4
3. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Data Model Structure . . . . . . . . . . . . . . . . . . . . 5
4.1. Integrity measurement . . . . . . . . . . . . . . . . . . 5
4.2. Cryptography security . . . . . . . . . . . . . . . . . . 6
4.2.1. Symmetrical cryptography . . . . . . . . . . . . . . 7
4.2.2. Asymmetrical cryptography . . . . . . . . . . . . . . 8
4.2.3. Hash function . . . . . . . . . . . . . . . . . . . . 10
4.2.4. Message authentication code . . . . . . . . . . . . . 10
4.2.5. Key derivation function . . . . . . . . . . . . . . . 11
4.3. Key management . . . . . . . . . . . . . . . . . . . . . 11
4.3.1. Key generation . . . . . . . . . . . . . . . . . . . 12
4.3.2. Key distribution . . . . . . . . . . . . . . . . . . 13
4.3.3. Key store . . . . . . . . . . . . . . . . . . . . . . 13
4.3.4. Key update . . . . . . . . . . . . . . . . . . . . . 13
4.3.5. Key backup . . . . . . . . . . . . . . . . . . . . . 14
4.3.6. Key destroy . . . . . . . . . . . . . . . . . . . . . 14
4.4. Cert management . . . . . . . . . . . . . . . . . . . . . 14
4.4.1. Cert management . . . . . . . . . . . . . . . . . . . 15
4.4.2. CRL management . . . . . . . . . . . . . . . . . . . 16
5. Infrastructure Layer YANG Module . . . . . . . . . . . . . . 17
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26
7. Security Considerations . . . . . . . . . . . . . . . . . . . 26
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 26
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
9.1. Normative References . . . . . . . . . . . . . . . . . . 26
9.2. Informative References . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction
Network devices such as switches, routers, and firewalls are the
fundamental elements that a network is composed of. The
vulnerabilities of a network device are always exploited by attackers
to start up eavesdropping, spoofing, and man-in-middle attacks etc.
Hence it is significant to assess the security postures for
identifying the possible threats and vulnerabilities of a network
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device in anytime. The SACM working group is aim to provide such a
mechanism to acquire the posture information, which including the
security related configuration and status attributes, on the target
devices and evaluate their security postures by comparing with the
pre-defined benchmarking criteria. Furthermore, the evaluation
results are able to be the guidance to enforce the corresponding
security hardening measurement on the devices under assessment. But
this hardening process is out of scope of this draft.
This draft and each of the companion document define a subset of
posture information that have to be collected for the assessment
purpose mentioned above. This entire set of posture information is
so called security baseline of a network device that is proposed in
the companion draft [I-D.draft-xia-sacm-dp-security-profile]. The
proposed security baseline is presented in the fashion of yang data
model. And the security baseline yang data model can be requested or
subscribed by a collector agent such as a yang push client [draft-
birkholz-sacm-yang-content]. The output of such a collector agent is
then encapsulated into the SACM content and statement elements
[draft-ietf-sacm-information-mdoel] and published to other SACM
components (e.g. repository and evaluator) [draft-mandm-sacm-
architecture-01]. Please note that document is only focus on the
yang data model of security baseline, the messaging mechanisms is out
of scope of this document. They are specified in other documents.
1.1. Infrastructure layer security baseline
In general, the entire security baseline of a network device is
divided into three layers, namely the application layer, the network
layer, and the infrastructure layer. This document focus on the data
model on infrastructure layer. The infrastructure layer security
baseline herein refers to the configuration and status attributes of
security functions that secure the device itself, and the fundamental
security capabilities provided by the device to the upper layer
applications. More specifically, the essential configurable and key
status attributes of the following function/capability modules are
sorted out to generate the infrastructure layer security baseline
data model.
o Integrity measurement: the integrity measurement herein refers to
the functions such as trust computing to protect the device
against the replacement and/or tampering attacks. For example,
the trust boot and/or secure boot provide the integrity validation
service for the kernel and early stage executable code (bios and
bootloader) in bootstrapping phases, and the digital signature
protect the upper layer software applications against the
tampering attacks in software updating phases.
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o Cryptography algorithms: the cryptographic algorithms are the most
important capabilities that the device provides to the upper layer
security applications. For example, the symmetric (e.g. DES,
AES) and asymmetric (eg. RSA, ECC) cryptographic algorithms can
be used for sensitive data encryption, and peers authentication.
And the key derivation function (KDF) can be used for secret key
generation and passcode storage.
o Key management: the cryptographic key (pair) and its associated
algorithm provide various security features for network devices.
How we manage the key (pair) provisioned in a network device is a
critical issue. The key management covers the attributes to show
how the key (pair) is managed in the key's lifecycle (e.g. from
generation to destroy).
o Certificate management: the certificates are normally provided by
the device for authentication purpose. The certificate management
refers to how the certificates and the certificates revocation
list (CRL) is requested, updated, and validated in the device.
The practical security baseline of a network device depends on the
device type, the supported features, the requirements of operators
and enterprises, and the role it plays exactly in the network. Owing
to such a number of variance, it is impossible to design a
comprehensive and unified data model for all devices. Thus the
proposed data model in this document is only used to benchmark the
most widely deployed security related functions and capabilities.
And we would like it to be an extensible model so that more
attributes are able to be added as per the practical use case
scenario.
2. Terminology
2.1. Key Words
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 [RFC2119].
2.2. Definition of Terms
This document uses the terms defined in[I-D.ietf-sacm-terminology].
3. Tree Diagrams
A simplified graphical representation of the data model is used in
this document. The meaning of the symbols in these diagrams is as
follows:
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o Brackets "[" and "]" enclose list keys.
o Abbreviations before data node names: "rw" means configuration
(read-write) and "ro" state data (read-only).
o Symbols after data node names: "?" means an optional node and "*"
denotes a "list" and "leaf-list".
o Parentheses enclose choice and case nodes, and case nodes are also
marked with a colon (":").
o Ellipsis ("...") stands for contents of subtrees that are not
shown.
4. Data Model Structure
As mentioned above, the top-level structure of the data model is
shown in the following figure. There are four subtrees in the tree
diagram. Each of the following sub-sections specifies the detail of
an individual subtree.
module: infrastructure-layer-baseline
+--rw infrastructure-layer-baseline
+--rw integrity-measurement
| . . . . . .
+--rw cryptography-algorithms
| . . . . . .
+--rw key-management
| . . . . . .
+--rw certificate-management
. . . . . .
4.1. Integrity measurement
The purpose of integrity measurement is to prevent the upper layer
software applications, kernel, and early stage executable code (e.g.
BIOS and bootloader) from replacement and/or tampering in
bootstrapping and updating phases. Trusted boot and secure boot are
the two widely used techniques for protecting the device
bootstrapping. The read-only root of trust (RoT) should be always
stored in a SoC or TPM chip. For software updating, digital
signature has been demonstrated as a powerful tool to provide the
integrity protection service. In using digital signature, the
employed hash function and signature algorithm must be strong enough
so that attackers cannot force crack them in a short period of time.
Moreover, the public key used for verifying the signature should be
stored properly. For example, it can be wrapped in a certificate of
the software vendor or stored in the read-only SoC or TPM.
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module: integrity-measurement
+--rw integrity-measurement
+--rw bootstrapping
| +--rw trust-boot
| | +--ro tmp-version string
| | +--rw tpm-enable boolean
| | +---u hash-function
| | +--rw pcr-record* [pcr-number]
| | +--ro pcr-number unit8
| | +--ro measurement-item enumeration
| | +--ro pcr-value string
| | +--ro pcr-benchmark-value string
| | +--ro verify-result boolean
| +--rw secure-boot
| +--ro soc-model string
| +--ro measurement-item* enumeration
| +---u hash-function
| +---u signature-algorithm
| +--ro verification-public-key
| +--ro key-name string
| +--ro key-length unit16
| +--ro key-store-medium enumeration
+--rw software-update
+---u hash-function
+---u signature-algorithm
+--ro verification-public-key
+--ro key-name string
+--ro key-length unit16
+--ro key-store-medium enumeration
4.2. Cryptography security
Almost all the security features of communication network are built
on the basis of modern cryptography. For example, the cryptographic
algorithms are usually used to perform transmission data encryption
and peers authentication. However, as the computing capability of
the present computing system is getting faster and faster, more and
more cryptographic algorithms can be brute force cracked in a short
period of time. Therefore the algorithm has to be selected
appropriately for different use case scenarios. And the
configuration parameters must be set within an appropriate range so
that the used algorithm is strong enough.
As a fundamental capabilities provided by the device, the practical
configurations of each supported cryptographic algorithm varies as
per the upper layer application that employs the algorithm. This
section organizes the algorithms and their configuration parameters
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into groupings so that the upper layer applications can reference/
reuse them appropriately.
In general, this section covers the following cryptographic algorithm
groupings:
o Symmetric algorithms and their configurable parameters.
o Asymmetric algorithms and their configurable parameters.
o Hash functions.
o Message authentication code (MAC) methods and their configurable
parameters.
o Key derivation functions (KDF) and their configurable parameters.
All the groupings enable the collection of the specific algorithms
and their parameters on a case-by-case basis.
4.2.1. Symmetrical cryptography
The symmetric algorithms are typically used for providing data
confidential service. The encryption and decryption process of
symmetrical algorithms make use of two identical keys. And, most of
the symmetrical algorithms are typically belong to either block
ciphers or stream ciphers.
Block cipher: block cipher divides the plaintext in to a number of
blocks with a constant bit length. And the last plaintext block
should be filled to fit the bit length requirement. Then each of the
plaintext blocks is encrypted individually. However, if a plaintext
piece repeats several times in a long data stream, it is easier for
an attacker to guess the original plaintext from the repeated
ciphertext. Hence, some other operation modes of block cipher,
including cipher block chaining (CBC) mode, cipher feedback (CFB)
mode, counter mode (CRT), and Galois counter mode (GCM), are proposed
to introduce a random bit stream, which is named initialization
vector (IV), to augment the randomness of the original plaintext.
The used random number generator must meet the randomness requirement
so that the IV value is unpredicted. In addition, the bit length of
IV should be the same as the bit length of a plaintext block for most
block cipher working mode. But for CRT and GCM, the length of IV is
optional.
Stream cipher: unlike block cipher, which encrypt a single plaintext
block at one time, stream-cipher encrypt every bit of a plaintext
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separately. The stream cipher algorithms also use IV to increase the
randomness of the original plaintext.
grouping: symmetric-cryptosystem
+--rw (algorithm-type)
+--:(stream-cipher)
| +--rw algorithm identityref
| +--rw iv-length unit16
| +--rw iv-randomness decimal64
+--:(block-cipher)
+--rw algorithm identityref
+--rw operation-mode identityref
+--rw padding-method identityref
+--rw iv-length unit16
+--rw iv-randomness decimal64
4.2.2. Asymmetrical cryptography
The asymmetric cryptography is also called public key cryptography.
In contrast to the symmetric one, asymmetric cryptography always
employs a key pair that contains two different keys to deal with the
encryption and decryption work. The private key in the key pairs is
held and used only by the owner. The other key in the key pairs is
theoretically public to everyone. The asymmetric cryptography
algorithms are not only able to provide data encryption, but also
provide authentication and/or integrity protection services (e.g.
digital signature).
Asymmetric encryption: RSA is the most commonly used asymmetrical
encryption algorithm. In the use of RSA, the smaller the public
exponent is, the higher efficiency the algorithm has. In the other
side, it will be much easier to crack the algorithm and recover the
original plaintext if the public exponent is too small. Hence it has
to trade off the value of public exponent. In addition, the RSA is
recommend to use optimal asymmetrical encryption padding (OAEP) to
fill up the original plaintext.
grouping: encryption-algorithm
+--rw encryption-algorithm
+--rw rsa-attributes
+--rw algorithm identityref
+--rw padding-method identityref
+--rw public-key
+--rw public-exponent unit32
+--rw modulo-value unit32
Digital signature: digital signature is a powerful tool to provide
integrity protection. DSA, RSA, and ECDSA are three of the most
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popular signature algorithms. By using RSA in digital signature, it
is better to use PSS for padding. If the data is required to be
encrypted and signed at the same time, it is suggest to sign the data
before encrypting.
grouping: signature-algorithms
+--rw (asymmetric-algorithms)
+--:(rsa)
| +--rw algorithm identityref
| +--rw padding-method identityref
| +--rw public-key
| +--rw public-exponent unit32
| +--rw modulo-value unit32
+--:(dsa)
| +--rw temporary-key
| | +--rw key-length unit16
| | +--rw randomness decimal64
| +--rw prime-number
| +--rw prime-modulo unit32
| +--rw prime-order unit32
+--:(ecdsa)
+--rw temporary-key
| +--rw key-length unit16
| +--rw randomness decimal64
+---u hash-function
+--rw prime-modulo unit32
+--rw prime-order unit32
+--rw ec-parameters
+--rw coefficient-a unit16
+--rw coefficient-b unit16
Key exchange: key exchange is meant to establish key pairs between
communication peers. The peers send key material rather than key
itself to each other.
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grouping: key-exchange
+--rw (key-exchange)
+--:(dh)
| +--rw dh-handshake
| +--rw prime-number-length unit32
| +--rw public-integer-length unit32
+--:(ecdh)
+--rw ecdh-handshake
+--rw prime-modulo unit32
+--rw ec-parameters
| +--rw coefficient-a unit16
| +--rw coefficient-b unit16
+--rw primitive-elements
+--rw coordinate-x unit16
+--rw coordinate-y unit16
4.2.3. Hash function
Hash functions are normally used to perform integrity measurement.
The output of a Hash function is a digest with a constant bit length
for a segment of messages or code. The digest is unique and unable
to be reconstructed if the original message/code is tampered. The
Hash function is widely used in digital signature, message
authentication code, password hash storage, and etc.
grouping: hash-function
+--rw hash-function
+--rw algorithm identityref
+--rw padding-method identityref
+--ro digest-length unit16
4.2.4. Message authentication code
Similar to digital signature, message authentication code (MAC) is
another method to provide integrity protection service. MAC applies
hash function or block cipher algorithms on the message plaintext
coupled with a pre-shared session key. It must be noted that, it is
unsafe if simply extend the message with the session key.
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grouping: message-authentication-code
+--rw (message-authentication-code)
+--: (hmac)
| +--rw message-structure enumeration
| | {prefix|postfix|hmac structure}
| +---u hash-function
| +--rw session-key
| +--rw key-length unit16
| +--rw randomness decimal64
+--: (cmac)
+--rw block-cipher-algorithm identityref
+--rw block-length unit16
+--rw iv-length unit16
+--rw randomness decimal64
4.2.5. Key derivation function
Key derivation function derives one or more keys from a master key or
entered password. A salt value is generated by a random number
generator to introduce the randomness of the derived keys.
grouping: key-derivation-function
+--rw (algorithm)
+--:(pbkdf2)
| +---u hash-function
| +--rw iteration unit16
| +--rw derived-key-length unit16
| +--rw code-length unit16
| +--rw salt-attributes
| +--rw salt-length unit16
| +--rw randomness decimal64
+--:(scrypt)
+--rw code-length unit16
+--rw cpu-memory-usage unit16
+--rw block-size unit8
+--rw parallelization unit8
+--rw derived-key-length unit16
+--rw salt-attributes
+--rw salt-length unit16
+--rw randomness decimal64
4.3. Key management
Cryptographic key plays the most important role in a cryptographic
system. . If the key is disclosed or tampered, the corresponding
service is not reliable any more. Hence the network device must
provide the confidentiality and integrity protection for a key in its
entire lifecycle. This section contains a list of key (pair) and
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their configuration/status parameters corresponding to different
lifecycle phases. Each of the key (pair) is used in a specific use
case.
module: key-management
+--rw key-management* [key-name]
+--rw key-name string
+--rw key-length* unit16
+--rw lifetime unit32
+--rw key-type enumeration
+--rw num-of-keys unit8
+--rw key-generation
| . . . . . .
+--rw key-distribution
| . . . . . .
+--rw key-store
| . . . . . .
+--rw key-backup
| . . . . . .
+--rw key-update
| . . . . . .
+--rw key-destroy
. . . . . .
4.3.1. Key generation
There are three types of commonly used key generation methods. The
first method is on the basis of random number generator. In this
method, the referenced random number generator has to ensure the
generated key is unpredicted. The second key generation method is
based on the manual entered password. However, the entered password
is not meet the randomness requirement. In this case, a key
derivation function (e.g. PBKDF2) is applied to derive the key. The
last key generation method is key exchange such as Diffie-Hellman
(DH) protocol. This kind of method requires the peers to
authenticate each other before exchange the key material.
submodule: key-generation
+--rw key-generation
+--: (random-number-generator)
| +--rw key-randomness decimal64
+--: (key-derivation-function)
| +---u key-derivation-function
+--: (key-exchange)
+--rw cert-name string
+---u key-exchange
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4.3.2. Key distribution
Key distribution aims to send the generated keys to authorized
entities in a secure fashion. The confidentiality and integrity
issues of the key in distribution are usually addressed by using
either a secure transport protocol or digital envelop.
[I-D.ietf-netconf-tls-client-server], IPsec [I-D.draft-tran-ipsecme-
yang], or SSH [I-D.ietf-netconf-ssh-client-server], or digital
envelop.
submodule: key-distribution
+--rw key-distribution?
+--rw symmetrical-key
+--: (secure-transport-protocol)
| +--rw tls-config
| | [I-D.ietf-netconf-tls-client-server]
| +--rw ipsec-config
| | [I-D.draft-tran-ipsecme-yang]
| +--rw ssh-config
| [I-D.ietf-netconf-ssh-client-server]
+--: (digital-envolop)
+---u symmetric-algorithm
+--rw encryption-key-name string
+--rw encryption-key-length unit16
4.3.3. Key store
A typical key management system has three layers. The master keys
that consumed by upper layer applications are in the top layer. The
key in the middle layer, which is called key encryption key (KEK), is
used to encrypt the master keys. And the KEK itself is encrypted by
the root key which stays in the bottom layer of the three layer key
management system.
submodule: key-store
+--rw key-store
+--ro store-medium {TPM|HSM|HDD} enumeration
+--rw key-component* [component-name]
+--rw component-name string
+--ro store-medium enumeration
4.3.4. Key update
Network device must update the key in a reasonable period of time.
Otherwise the long term used key will attract attackers to crack it.
The practical update period of a certain key depends on the
application the key serves and the strength (i.e. bit length) of the
key itself.
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submodule: key-update
+--rw key-update
+--rw next-update-time yang-type:date-and-time
+--rw hold-expired-key boolean
+--rw update-mode
+--: (manual)
| +--rw manual-enable boolean
+--: (auto)
+--rw auto-enble boolean
+--rw update-period unit8
4.3.5. Key backup
The loss of keys will lead to data loss. Therefore, according to the
different use case scenarios, a key (pair) may need to backup. It is
better to divide the key into several parts and store them into
different storage devices.
submodule: key-backup
+--rw key-backup?
+--rw backup-enable boolean
+--rw backup-expire-time yang-type:date-and-time
+--rw backup-component* [component-name]
+--rw component-name string
+--ro backup-medium enumeration
4.3.6. Key destroy
The key and its associated key material must be destroyed when it is
expired. Otherwise the expired key will be used by attackers to
decrypt the data encrypted by this key. Also, the expired key can be
used to analysis the cryptosystem.
submodule: key-destory
+--rw key-destory
+--rw method {one|zerod|random number} enumeration
+--rw number-of-times unit8
4.4. Cert management
The TLS/DTLS and IPsec have been demonstrated as powerful security
tools to provide data confidentiality and integrity services between
network elements. In order to protect the TLS/DTLS or the IPsec
connection against man-in-middle attack, peers have to authenticate
from each other before connection establishing. The pre-shared key
and the certificate are two of the most widely used methods to
authenticate peers' identities. However, it requires to re-configure
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the pre-shared keys on all other endpoints/network elements if an
additional network device is added in network. This complicated re-
configuration process is easy to make errors. In the other hand,
certificate is an idea way to extend authentications to a much larger
scale of network. Peers request certificates that contain their
entity information and public keys from certification authority (CA)
in advance. The connection will be established only if the
certificates are verified.
For a specific network device, such as switch and router, the
certification service normally includes certificates request and
updating, certificates validity check.
module: cert-management
+--rw cert-management
+--rw cert-management
| . . . . . .
+--rw crl-management
. . . . . .
4.4.1. Cert management
A cert request file that contains the device public key and entity
information is sent to the CA to apply a certificate. A CMP session
is configured to request and update the certificates. A build-in
default certificate in the device is used for identity authentication
for CMP session. And the certificate must be updated in a reasonable
period of time via CMP session.
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module: cert-management
+--rw cert-management* [cert-name]
+--rw cert-name string
+--ro version string
+--ro serial-number string
+--ro signature-algorithm identityref
+--ro issuer-name string
+--rw cert-request
| +--rw cmp-session-name string
+--ro validity
| +--ro start-time yang-type:date-and-time
| +--ro end-time yang-type:data-and-time
+--ro subject-public-key
| +--ro public-key-algorithm identityref
| +--ro public-key-length unit16
| +--ro exponent unit32
+--rw cert-auto-update
+--rw cert-name string
+--rw pki-domain-name string
+--rw cmp-session-name string
+--rw auto-update-enable boolean
+--rw trigger-condition
+--rw validity-percentage-number unit8
grouping: cmp-session-config
+--rw cmp-session-config* [session-name]
+--rw domain-name string
+--rw session-name string
+--rw entity-name string
+--rw key-name string
+--rw ca-server-name string
+--rw default-cert-name string
+--rw cmp-server-url string
4.4.2. CRL management
The certificate revocation list (CRL) contains the invalid/expired
certificates. It is equivalent to a blacklist of certificates issued
by CA. The validity of a received cert is able to be checked by
comparing with the CRL. The CRL need to update from CA by either an
automatic or manual way.
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submodule: crl-management
+--rw crl-management
+--rw cert-validity-check-enable boolean
+--rw crl-update
+--rw previous-update-time yang-type:date-and-time
+--rw auto-update
| +--rw auto-update-enable boolean
| +--rw update-period unit32
| +--rw next-update-time yang-type:date-and-time
| +--rw update-method {http|ldap} enumeration
+--rw manual-update
+--rw manual-update-enable boolean
+--rw update-method {http|ldap} enumeration
5. Infrastructure Layer YANG Module
This section shows a fraction of the infrastructure layer security
baseline YANG modules.
module ietf-integrity-measurement{
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-integrity-measurement";
prefix "im";
import ietf-yang-types{
prefix yang;
reference
"RFC6991: Common Yang Data Types";
}
organization
"Huawei Technologies";
contact
"Yue Dong: dongyue6@huawei.com"
"Liang Xia: Frank.xialiang@huawei.com"
description
"This module defines the configuration and status parameters of the
functions that provide the integrity services in the bootstrapping
and software updating phases.";
identity hash-algorithms {
description
"base identities of hash algorithms options";
}
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identity md5 {
base hash-algorithms;
description
"The MD5 algorithm";
}
identity sha1 {
base hash-algorithms;
description
"The SHA-1 algorithm";
reference
"RFC3174: US Secure Hash Algorithm 1 (SHA1).";
}
identity sha224 {
base hash-algorithms;
description
"The SHA-224 algorithm.";
reference
"RFC6234: US Secure Hash Algorithms (SHA and SHA based HMAC and
HKDF).";
}
identity sha256 {
base hash-algorithms;
description
"The SHA-256 algorithm.";
reference
"RFC6234: US Secure Hash Algorithms (SHA and SHA based HMAC and
HKDF).";
}
identity sha384 {
base hash-algorithms;
description
"The SHA-384 algorithm.";
reference
"RFC6234: US Secure Hash Algorithms (SHA and SHA based HMAC and
HKDF).";
}
identity sha512 {
base hash-algorithm;
description
"The SHA-512 algorithm.";
reference
"RFC6234: US Secure Hash Algorithms (SHA and SHA based HMAC and
HKDF).";
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}
identity rsa-algorithms {
description
"rsa algorithms with different key length";
}
identity rsa1024 {
base rsa-algorithms;
description
"The RSA algorithm using a 1024 bit key";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications 2.1"
}
identity rsa2048 {
base rsa-algorithms;
description
"The RSA algorithm using a 2048 bit key";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications 2.1"
}
identity rsa3072 {
base rsa-algorithms;
description
"The RSA algorithm using a 3072 bit key";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications 2.1"
}
identity rsa4096 {
base rsa-algorithms;
description
"The RSA algorithm using a 4096 bit key";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications 2.1"
}
identity rsa7680 {
base rsa-algorithms;
description
"The RSA algorithm using a 7680 bit key";
reference
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"RFC3447: Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications 2.1"
}
identity rsa15360 {
base rsa-algorithms;
description
"The RSA algorithm using a 15360 bit key";
reference
"RFC3447: Public-Key Cryptography Standards (PKCS) #1: RSA
Cryptography Specifications 2.1"
}
identity rsa-padding {
description
"The identities of padding methods for rsa.";
}
identity oaep {
base rsa-padding;
description
"The OAEP padding method for RSA.";
}
identity pss {
base rsa-padding;
description
"The PSS padding method for RSA.";
}
container integrity-measurement {
container bootstrapping {
container trust-boot {
leaf tpm-version {
type string;
description
"version of the tpm chip";
}
leaf tpm-enable {
type boolean;
description
"switch of the trust boot function";
}
uses hash-function
list pcr-record {
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key "pcr-number";
leaf pcr-number {
type unit8;
description
"Number of pcr register";
}
leaf measurement-item{
type enumeration {
enum bios;
enum bootloader;
enum kernel;
enum patch;
}
description
"This property shows which item is measured and recored by
the pcr";
}
leaf pcr-value {
type string;
description
"The practical measurement value";
}
leaf pcr-benchmark-value {
type string;
description
"The pre-defined benchmark criterion";
}
leaf verify-result {
type boolean;
description
"The benchmark result for each pcr recorded value";
}
}
}
container secure-boot {
leaf soc-model {
type string;
description
"Model of the used SoC";
}
leaf-list measurement-items {
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type enumeration {
enum bios;
enum bootloader;
enum kernel;
enum patch;
}
description
"List of the items to be measured in the secure boot
process";
}
uses hash-function
uses signature-algorithm
container verification-pub-key {
leaf key-name {
type string;
description
"Name of the public key for verfication";
}
leaf key-length {
type unit16;
description
"Length of the public key"
}
leaf store-medium {
type enumeration {
enum tmp;
enum soc;
enum hdd;
enum hsm;
}
description
"This property describes where the public key stores"
}
}
}
}
container software-update {
uses hash-function;
uses signature-algorithm;
container verification-pub-key {
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leaf key-name {
type string;
description
"Name of the public key for verification";
}
leaf key-length {
type unit16;
description
"Length of the public key";
}
leaf store-medium {
type enumeration {
enum tpm;
enum soc;
enum hdd;
enum hsm;
}
description
"This property decribes where the pub key stores"
}
}
}
}
grouping hash-function {
description
"A group of Hash functions and their parameters";
leaf algorithm {
type identityref {
base "hash-algorithm";
}
description
"Identities of the used Hash algorithm";
}
leaf padding-method {
type identityref;
description
""
}
leaf digest-length {
type unit16;
description
"The length of the Hash output";
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}
}
grouping signature-algorithms {
"A group of algorithms and their configurable parameters for digital
signature";
choice algorithm-type {
case rsa {
leaf algorithm {
type identityref {
base "rsa-algorithm";
}
description
"identities of the rsa algorithms for digital signature";
}
leaf padding-method {
type identityref;
description
"identities of padding method for the used algorithm"
}
container pub-key {
leaf public-exponent {
type unit32;
description
"value of public exponent";
}
leaf modulo-value {
type unit32;
description
"value of modulo";
}
}
}
case dsa {
container tempory-key {
leaf key-length {
type unit16;
description
"The length of the tempory key.";
}
leaf randomness {
type decimal64;
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description
"This value represents the randomness of this key.";
}
}
container prime-number {
leaf prime-modulo {
type unit32;
description
"value of modulo";
}
leaf prime-order {
type unit32;
description
"value of prime number";
}
}
}
case ecdsa {
containter tempory-key {
leaf key-length {
type unit16;
description
"The length of the tempory key that is generated by a
random number generator.";
}
leaf randomness {
type decimal64
description
"This value represents the randomness of the key. It is
generated by a tool like sts 2.1.";
}
}
leaf prime-modulo {
type unit32;
description
"value of modulo";
}
leaf prime-order {
type unit32;
description
"value of order";
}
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uses hash-function
container ec-parameter {
leaf coefficient-a {
type unit8;
description
"constant coefficient of the selected elliptic curve.";
}
leaf coefficient-b {
type unit8;
description
"constant coefficient of the selected elliptic curve.";
}
}
}
}
}
}
6. IANA Considerations
TBD
7. Security Considerations
TBD.
8. Acknowledgements
TBD
9. References
9.1. Normative References
[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>.
9.2. Informative References
[I-D.ietf-netconf-ssh-client-server]
Watsen, K. and G. Wu, "YANG Groupings for SSH Clients and
SSH Servers", draft-ietf-netconf-ssh-client-server-05
(work in progress), October 2017.
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[I-D.ietf-netconf-tls-client-server]
Watsen, K. and G. Wu, "YANG Groupings for TLS Clients and
TLS Servers", draft-ietf-netconf-tls-client-server-05
(work in progress), October 2017.
[I-D.ietf-sacm-information-model]
Waltermire, D., Watson, K., Kahn, C., Lorenzin, L., Cokus,
M., Haynes, D., and H. Birkholz, "SACM Information Model",
draft-ietf-sacm-information-model-10 (work in progress),
April 2017.
[I-D.ietf-sacm-terminology]
Birkholz, H., Lu, J., Strassner, J., Cam-Winget, N., and
A. Montville, "Security Automation and Continuous
Monitoring (SACM) Terminology", draft-ietf-sacm-
terminology-14 (work in progress), December 2017.
[I-D.mandm-sacm-architecture]
Montville, A. and B. Munyan, "Security Automation and
Continuous Monitoring (SACM) Architecture", draft-mandm-
sacm-architecture-01 (work in progress), March 2018.
[I-D.tran-ipsecme-yang]
Tran, K., Wang, H., Nagaraj, V., and X. Chen, "Yang Data
Model for Internet Protocol Security (IPsec)", draft-tran-
ipsecme-yang-00 (work in progress), October 2015.
[I-D.xia-sacm-nid-dp-security-baseline]
Xia, L. and G. Zheng, "The Data Model of Network
Infrastructure Device Data Plane Security Baseline",
draft-xia-sacm-nid-dp-security-baseline-01 (work in
progress), January 2018.
Authors' Addresses
Yue Dong
Huawei
Email: dongyue6@huawei.com
Liang Xia
Huawei
Email: frank.xialiang@huawei.com
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