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 This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on November 26, 2018. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect Dong & Xia Expires November 26, 2018 [Page 1] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. 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 Dong & Xia Expires November 26, 2018 [Page 2] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 3] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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: Dong & Xia Expires November 26, 2018 [Page 4] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 5] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 Dong & Xia Expires November 26, 2018 [Page 6] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 Dong & Xia Expires November 26, 2018 [Page 7] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 Dong & Xia Expires November 26, 2018 [Page 8] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 9] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 10] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 Dong & Xia Expires November 26, 2018 [Page 11] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 Dong & Xia Expires November 26, 2018 [Page 12] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 13] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 Dong & Xia Expires November 26, 2018 [Page 14] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 15] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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. Dong & Xia Expires November 26, 2018 [Page 16] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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"; } Dong & Xia Expires November 26, 2018 [Page 17] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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)."; Dong & Xia Expires November 26, 2018 [Page 18] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 } 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 Dong & Xia Expires November 26, 2018 [Page 19] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 "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 { Dong & Xia Expires November 26, 2018 [Page 20] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 { Dong & Xia Expires November 26, 2018 [Page 21] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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 { Dong & Xia Expires November 26, 2018 [Page 22] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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"; Dong & Xia Expires November 26, 2018 [Page 23] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 } } 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; Dong & Xia Expires November 26, 2018 [Page 24] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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"; } Dong & Xia Expires November 26, 2018 [Page 25] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 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, . 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. Dong & Xia Expires November 26, 2018 [Page 26] Internet-Draft Network Device Infra. Layer Sec. Baseline May 2018 [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 Dong & Xia Expires November 26, 2018 [Page 27]