.. Modifications Copyright © 2017-2018 AT&T Intellectual Property.

.. Licensed under the Creative Commons License, Attribution 4.0 Intl.
   (the "License"); you may not use this documentation except in compliance
   with the License. You may obtain a copy of the License at

.. https://creativecommons.org/licenses/by/4.0/

.. Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.


VNF Security
----------------------

The objective of this section is to provide the key security
requirements that need to be met by VNFs. The security requirements are
grouped into five areas as listed below. Other security areas will be
addressed in future updates. These security requirements are applicable
to all VNFs. Additional security requirements for specific types of VNFs
will be applicable and are outside the scope of these general
requirements.

Section 4.3 Security in *VNF Guidelines* outlines
the five broad security areas for VNFs that are detailed in the
following sections:

-  **VNF General Security**: This section addresses general security
   requirements for the VNFs that the VNF provider will need to address.

-  **VNF Identity and Access Management**: This section addresses
   security requirements with respect to Identity and Access Management
   as these pertain to generic VNFs.

-  **VNF API Security**: This section addresses the generic security
   requirements associated with APIs. These requirements are applicable
   to those VNFs that use standard APIs for communication and data
   exchange.

-  **VNF Security Analytics**: This section addresses the security
   requirements associated with analytics for VNFs that deal with
   monitoring, data collection and analysis.

-  **VNF Data Protection**: This section addresses the security
   requirements associated with data protection.

VNF General Security Requirements
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This section provides details on the VNF general security requirements
on various security areas such as user access control, network security,
ACLs, infrastructure security, and vulnerability management. These
requirements cover topics associated with compliance, security patching,
logging/accounting, authentication, encryption, role-based access
control, least privilege access/authorization. The following security
requirements need to be met by the solution in a virtual environment:

General Security Requirements

Integration and operation within a robust security environment is necessary
and expected. The security architecture will include one or more of the
following: IDAM (Identity and Access Management) for all system and
applications access, Code scanning, network vulnerability scans, OS,
Database and application patching, malware detection and cleaning,
DDOS prevention, network security gateways (internal and external)
operating at various layers, host and application based tools for
security compliance validation, aggressive security patch application,
tightly controlled software distribution and change control processes
and other state of the art security solutions. The VNF is expected to
function reliably within such an environment and the developer is
expected to understand and accommodate such controls and can expected
to supply responsive interoperability support and testing throughout
the product’s lifecycle.


.. req::
    :id: R-23740
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** implement and enforce the principle of least privilege
    on all protected interfaces.

.. req::
    :id: R-61354
    :target: VNF
    :keyword: MUST

    The VNF **MUST** implement access control list for OA&M
    services (e.g., restricting access to certain ports or applications).

.. req::
    :id: R-92207
    :target: VNF
    :keyword: SHOULD

    The VNF **SHOULD** implement a mechanism for automated and
    frequent "system configuration (automated provisioning / closed loop)"
    auditing.

.. req::
    :id: R-23882
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** provide the capability for the Operator to run security
    vulnerability scans of the operating system and all application layers.

.. req::
    :id: R-46986
    :target: VNF
    :keyword: SHOULD

    The VNF **SHOULD** have source code scanned using scanning
    tools (e.g., Fortify) and provide reports.

.. req::
    :id: R-99771
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** have all code (e.g., QCOW2) and configuration files
    (e.g., HEAT template, Ansible playbook, script) hardened, or with
    documented recommended configurations for hardening and interfaces that
    allow the Operator to harden the VNF. Actions taken to harden a system
    include disabling all unnecessary services, and changing default values
    such as default credentials and community strings.

.. req::
    :id: R-19768
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** support Layer 3 VPNs that enable segregation of
    traffic by application (i.e., AVPN, IPSec VPN for Internet routes).

.. req::
    :id: R-33981
    :target: VNF
    :keyword: SHOULD

    The VNF **SHOULD** interoperate with various access control
    mechanisms for the Network Cloud execution environment (e.g.,
    Hypervisors, containers).

.. req::
    :id: R-40813
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** support the use of virtual trusted platform
    module.

.. req::
    :id: R-56904
    :target: VNF
    :keyword: MUST

    The VNF **MUST** interoperate with the ONAP (SDN) Controller so that
    it can dynamically modify the firewall rules, ACL rules, QoS rules, virtual
    routing and forwarding rules.

.. req::
    :id: R-69649
    :target: VNF
    :keyword: MUST

    The VNF **MUST** have all vulnerabilities patched as soon
    as possible. Patching shall be controlled via change control process
    with vulnerabilities disclosed along with mitigation recommendations.

.. req::
    :id: R-78010
    :target: VNF
    :keyword: MUST

    The VNF **MUST** use the NCSP's IDAM API for Identification,
    authentication and access control of customer or VNF application users.

.. req::
    :id: R-42681
    :target: VNF
    :keyword: MUST

    The VNF **MUST** use the NCSP's IDAM API or comply with
    the requirements if not using the NCSP's IDAM API, for identification,
    authentication and access control of OA&M and other system level
    functions.

.. req::
    :id: R-62498
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** support encrypted access protocols, e.g., TLS,
    SSH, SFTP.

.. req::
    :id: R-79107
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API, enforce
    a configurable maximum number of Login attempts policy for the users.
    VNF provider must comply with "terminate idle sessions" policy.
    Interactive sessions must be terminated, or a secure, locking screensaver
    must be activated requiring authentication, after a configurable period
    of inactivity. The system-based inactivity timeout for the enterprise
    identity and access management system must also be configurable.

.. req::
    :id: R-35144
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API, comply
    with the NCSP's credential management policy.

.. req::
    :id: R-46908
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API, comply
    with "password complexity" policy. When passwords are used, they shall
    be complex and shall at least meet the following password construction
    requirements: (1) be a minimum configurable number of characters in
    length, (2) include 3 of the 4 following types of characters:
    upper-case alphabetic, lower-case alphabetic, numeric, and special,
    (3) not be the same as the UserID with which they are associated or
    other common strings as specified by the environment, (4) not contain
    repeating or sequential characters or numbers, (5) not to use special
    characters that may have command functions, and (6) new passwords must
    not contain sequences of three or more characters from the previous
    password.

.. req::
    :id: R-39342
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API, comply
    with "password changes (includes default passwords)" policy. Products
    will support password aging, syntax and other credential management
    practices on a configurable basis.

.. req::
    :id: R-40521
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API, support
    use of common third party authentication and authorization tools such
    as TACACS+, RADIUS.

.. req::
    :id: R-41994
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API, comply
    with "No Self-Signed Certificates" policy. Self-signed certificates
    must be used for encryption only, using specified and approved
    encryption protocols such as TLS 1.2 or higher or equivalent security
    protocols such as IPSec, AES.

.. req::
    :id: R-23135
    :target: VNF
    :keyword: MUST

    The VNF **MUST**, if not using the NCSP's IDAM API,
    authenticate system to system communications where one system
    accesses the resources of another system, and must never conceal
    individual accountability.

.. req::
    :id: R-80335
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    For all GUI and command-line interfaces, the VNF **MUST** provide the
    ability to present a warning notice that is set by the Operator. A warning
    notice is a formal statement of resource intent presented to everyone
    who accesses the system.

.. req::
    :id: R-19082
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** allow the Operator to disable or remove any security
    testing tools or programs included in the VNF, e.g., password cracker,
    port scanner.

VNF Identity and Access Management Requirements
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

The following security requirements for logging, identity, and access
management need to be met by the solution in a virtual environment:


Identity and Access Management Requirements

.. req::
    :id: R-99174
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** allow the creation of multiple IDs so that
    individual accountability can be supported.

.. req::
    :id: R-42874
    :target: VNF
    :keyword: MUST

    The VNF **MUST** comply with Least Privilege (no more
    privilege than required to perform job functions) when persons
    or non-person entities access VNFs.

.. req::
    :id: R-71787
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    Each layer of the VNF **MUST** support access restriction
    independently of all other layers so that Segregation of Duties
    can be implemented.

.. req::
    :id: R-86261
    :target: VNF
    :keyword: MUST NOT

    The VNF **MUST NOT** allow vendor access to VNFs remotely.

.. req::
    :id: R-59391
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF MUST NOT not allow the assumption of the permissions of
    another account to mask individual accountability.

.. req::
    :id: R-64503
    :target: VNF
    :keyword: MUST

    The VNF **MUST** provide minimum privileges for initial
    and default settings for new user accounts.

.. req::
    :id: R-86835
    :target: VNF
    :keyword: MUST

    The VNF **MUST** set the default settings for user access
    to sensitive commands and data to deny authorization.

.. req::
    :id: R-81147
    :target: VNF
    :keyword: MUST

    The VNF **MUST** have greater restrictions for access and
    execution, such as up to 3 factors of authentication and restricted
    authorization, for commands affecting network services, such as
    commands relating to VNFs.

.. req::
    :id: R-49109
    :target: VNF
    :keyword: MUST

    The VNF **MUST** encrypt TCP/IP--HTTPS (e.g., TLS v1.2)
    transmission of data on internal and external networks.

.. req::
    :id: R-39562
    :target: VNF
    :keyword: MUST

    The VNF **MUST** disable unnecessary or vulnerable cgi-bin programs.

.. req::
    :id: R-15671
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide access controls that allow the Operator
    to restrict access to VNF functions and data to authorized entities.

.. req::
    :id: R-85419
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** support OAuth 2.0 authorization using an external
    Authorization Server.

.. req::
    :id: R-75041
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST**, if not integrated the Operator's Identity and Access
    Management system, support configurable password expiration.

.. req::
    :id: R-98391
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST**, if not integrated with the Operator's Identity and
    Access Management system, support Role-Based Access Control to enforce
    least privilege.

VNF API Security Requirements
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This section covers API security requirements when these are used by the
VNFs. Key security areas covered in API security are Access Control,
Authentication, Passwords, PKI Authentication Alarming, Anomaly
Detection, Lawful Intercept, Monitoring and Logging, Input Validation,
Cryptography, Business continuity, Biometric Authentication,
Identification, Confidentiality and Integrity, and Denial of Service.

The solution in a virtual environment needs to meet the following API
security requirements:


API Requirements

.. req::
    :id: R-43884
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** integrate with the Operator's authentication and
    authorization services (e.g., IDAM).

.. req::
    :id: R-33488
    :target: VNF
    :keyword: MUST

    The VNF **MUST** protect against all denial of service
    attacks, both volumetric and non-volumetric, or integrate with external
    denial of service protection tools.

.. req::
    :id: R-21652
    :target: VNF
    :keyword: MUST

    The VNF **MUST** implement the following input validation
    control: Check the size (length) of all input. Do not permit an amount
    of input so great that it would cause the VNF to fail. Where the input
    may be a file, the VNF API must enforce a size limit.

.. req::
    :id: R-54930
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** implement the following input validation controls:
    Do not permit input that contains content or characters inappropriate
    to the input expected by the design. Inappropriate input, such as
    SQL expressions, may cause the system to execute undesirable and
    unauthorized transactions against the database or allow other
    inappropriate access to the internal network (injection attacks).

.. req::
    :id: R-21210
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** implement the following input validation control
    on APIs: Validate that any input file has a correct and valid
    Multipurpose Internet Mail Extensions (MIME) type. Input files
    should be tested for spoofed MIME types.

VNF Security Analytics Requirements
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This section covers VNF security analytics requirements that are mostly
applicable to security monitoring. The VNF Security Analytics cover the
collection and analysis of data following key areas of security
monitoring:

-  Anti-virus software

-  Logging

-  Data capture

-  Tasking

-  DPI

-  API based monitoring

-  Detection and notification

-  Resource exhaustion detection

-  Proactive and scalable monitoring

-  Mobility and guest VNF monitoring

-  Closed loop monitoring

-  Interfaces to management and orchestration

-  Malformed packet detections

-  Service chaining

-  Dynamic security control

-  Dynamic load balancing

-  Connection attempts to inactive ports (malicious port scanning)

The following requirements of security monitoring need to be met by the
solution in a virtual environment.

Security Analytics Requirements


.. req::
    :id: R-48470
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support Real-time detection and
    notification of security events.

.. req::
    :id: R-22286
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support Integration functionality via
    API/Syslog/SNMP to other functional modules in the network (e.g.,
    PCRF, PCEF) that enable dynamic security control by blocking the
    malicious traffic or malicious end users.

.. req::
    :id: R-32636
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support API-based monitoring to take care of
    the scenarios where the control interfaces are not exposed, or are
    optimized and proprietary in nature.

.. req::
    :id: R-61648
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support event logging, formats, and delivery
    tools to provide the required degree of event data to ONAP.

.. req::
    :id: R-22367
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support detection of malformed packets due to
    software misconfiguration or software vulnerability.

.. req::
    :id: R-31961
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support integrated DPI/monitoring functionality
    as part of VNFs (e.g., PGW, MME).

.. req::
    :id: R-73223
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support proactive monitoring to detect and
    report the attacks on resources so that the VNFs and associated VMs can
    be isolated, such as detection techniques for resource exhaustion, namely
    OS resource attacks, CPU attacks, consumption of kernel memory, local
    storage attacks.

.. req::
    :id: R-58370
    :target: VNF
    :keyword: MUST

    The VNF **MUST** coexist and operate normally with commercial
    anti-virus software which shall produce alarms every time when there is a
    security incident.

.. req::
    :id: R-56920
    :target: VNF
    :keyword: MUST

    The VNF **MUST** protect all security audit logs (including
    API, OS and application-generated logs), security audit software, data,
    and associated documentation from modification, or unauthorized viewing,
    by standard OS access control mechanisms, by sending to a remote system,
    or by encryption.

.. req::
    :id: R-54520
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** log successful and unsuccessful authentication
    attempts, e.g., authentication associated with a transaction,
    authentication to create a session, authentication to assume elevated
    privilege.

.. req::
    :id: R-55478
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log logoffs.

.. req::
    :id: R-13344
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log starting and stopping of security
    logging.

.. req::
    :id: R-07617
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** log success and unsuccessful creation, removal, or
    change to the inherent privilege level of users.

.. req::
    :id: R-94525
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** log connections to the network listeners of the
    resource.

.. req::
    :id: R-31614
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log the field "event type" in the security audit
    logs.

.. req::
    :id: R-97445
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log the field "date/time" in the security audit
    logs.

.. req::
    :id: R-25547
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log the field "protocol" in the security audit logs.

.. req::
    :id: R-06413
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log the field "service or program used for access"
    in the security audit logs.

.. req::
    :id: R-15325
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log the field "success/failure" in the
    security audit logs.

.. req::
    :id: R-89474
    :target: VNF
    :keyword: MUST

    The VNF **MUST** log the field "Login ID" in the security audit logs.

.. req::
    :id: R-04982
    :target: VNF
    :keyword: MUST NOT

    The VNF **MUST NOT** include an authentication credential,
    e.g., password, in the security audit logs, even if encrypted.

.. req::
    :id: R-63330
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** detect when its security audit log storage
    medium is approaching capacity (configurable) and issue an alarm.

.. req::
    :id: R-41252
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support the capability of online storage of
    security audit logs.

.. req::
    :id: R-41825
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** activate security alarms automatically when
    a configurable number of consecutive unsuccessful login attempts
    is reached.

.. req::
    :id: R-43332
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** activate security alarms automatically when
    it detects the successful modification of a critical system or
    application file.

.. req::
    :id: R-74958
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** activate security alarms automatically when
    it detects an unsuccessful attempt to gain permissions
    or assume the identity of another user.

.. req::
    :id: R-15884
    :target: VNF
    :keyword: MUST

    The VNF **MUST** include the field "date" in the Security alarms
    (where applicable and technically feasible).

.. req::
    :id: R-23957
    :target: VNF
    :keyword: MUST

    The VNF **MUST** include the field "time" in the Security alarms
    (where applicable and technically feasible).

.. req::
    :id: R-71842
    :target: VNF
    :keyword: MUST

    The VNF **MUST** include the field "service or program used for
    access" in the Security alarms (where applicable and technically feasible).

.. req::
    :id: R-57617
    :target: VNF
    :keyword: MUST

    The VNF **MUST** include the field "success/failure" in the
    Security alarms (where applicable and technically feasible).

.. req::
    :id: R-99730
    :target: VNF
    :keyword: MUST

    The VNF **MUST** include the field "Login ID" in the Security
    alarms (where applicable and technically feasible).

.. req::
    :id: R-29705
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** restrict changing the criticality level of a
    system security alarm to users with administrative privileges.

.. req::
    :id: R-13627
    :target: VNF
    :keyword: MUST

    The VNF **MUST** monitor API invocation patterns to detect
    anomalous access patterns that may represent fraudulent access or other
    types of attacks, or integrate with tools that implement anomaly and
    abuse detection.

.. req::
    :id: R-21819
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support requests for information from law
    enforcement and government agencies.

.. req::
    :id: R-04492
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** generate security audit logs that can be sent
    to Security Analytics Tools for analysis.

.. req::
    :id: R-30932
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** log successful and unsuccessful access to VNF
    resources, including data.

.. req::
    :id: R-54816
    :target: VNF
    :keyword: MUST

    The VNF **MUST** support the storage of security audit logs
    for agreed period of time for forensic analysis.

.. req::
    :id: R-57271
    :target: VNF
    :keyword: MUST

    The VNF **MUST** provide the capability of generating security
    audit logs by interacting with the operating system (OS) as appropriate.

.. req::
    :id: R-84160
    :target: VNF
    :keyword: MUST

    The VNF **MUST** have security logging for VNFs and their
    OSs be active from initialization. Audit logging includes automatic
    routines to maintain activity records and cleanup programs to ensure
    the integrity of the audit/logging systems.

.. req::
    :id: R-34552
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** be implemented so that it is not vulnerable to OWASP
    Top 10 web application security risks.

VNF Data Protection Requirements
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This section covers VNF data protection requirements that are mostly
applicable to security monitoring.


Data Protection Requirements

.. req::
    :id: R-58964
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability to restrict read
    and write access to data handled by the VNF.

.. req::
    :id: R-83227
    :target: VNF
    :keyword: MUST

    The VNF **MUST** Provide the capability to encrypt data in
    transit on a physical or virtual network.

.. req::
    :id: R-32641
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability to encrypt data on
    non-volatile memory.Non-volative memory is storage that is
    capable of retaining data without electrical power, e.g.
    Complementary metal–oxide–semiconductor (CMOS) or hard drives.

.. req::
    :id: R-13151
    :target: VNF
    :keyword: SHOULD

    The VNF **SHOULD** disable the paging of the data requiring
    encryption, if possible, where the encryption of non-transient data is
    required on a device for which the operating system performs paging to
    virtual memory. If not possible to disable the paging of the data
    requiring encryption, the virtual memory should be encrypted.

.. req::
    :id: R-73067
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** use NIST and industry standard cryptographic
    algorithms and standard modes of operations when implementing
    cryptography.

.. req::
    :id: R-12467
    :target: VNF
    :keyword: MUST NOT

    The VNF **MUST NOT** use the SHA, DSS, MD5, SHA-1 and
    Skipjack algorithms or other compromised encryption.

.. req::
    :id: R-02170
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** use, whenever possible, standard implementations
    of security applications, protocols, and formats, e.g., S/MIME, TLS, SSH,
    IPSec, X.509 digital certificates for cryptographic implementations.
    These implementations must be purchased from reputable vendors or obtained
    from reputable open source communities and must not be developed in-house.

.. req::
    :id: R-70933
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the ability to migrate to newer
    versions of cryptographic algorithms and protocols with minimal impact.

.. req::
    :id: R-95864
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** support digital certificates that comply with X.509
    standards.

.. req::
    :id: R-12110
    :target: VNF
    :keyword: MUST NOT

    The VNF **MUST NOT** use keys generated or derived from
    predictable functions or values, e.g., values considered predictable
    include user identity information, time of day, stored/transmitted data.

.. req::
    :id: R-69610
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability of using X.509 certificates
    issued by an external Certificate Authority.

.. req::
    :id: R-47204
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** be capable of protecting the confidentiality and integrity
    of data at rest and in transit from unauthorized access and modification.


VNF Cryptography Requirements
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This section covers VNF cryptography requirements that are mostly
applicable to encryption or protocol meethods.

.. req::
    :id: R-48080
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** support an automated certificate management protocol
    such as CMPv2, Simple Certificate Enrollment Protocol (SCEP) or
    Automated Certificate Management Environment (ACME).

.. req::
    :id: R-93860
    :target: VNF
    :keyword: SHOULD
    :updated: casablanca

    The VNF **SHOULD** provide the capability to integrate with an
    external encryption service.

.. req::
    :id: R-44723
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** use symmetric keys of at least 112 bits in length.

.. req::
    :id: R-25401
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** use asymmetric keys of at least 2048 bits in length.

.. req::
    :id: R-52060
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability to configure encryption
    algorithms or devices so that they comply with the laws of the jurisdiction
    in which there are plans to use data encryption.

.. req::
    :id: R-83500
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability of allowing certificate
    renewal and revocation.

.. req::
    :id: R-29977
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability of testing the validity
    of a digital certificate by validating the CA signature on the certificate.

.. req::
    :id: R-24359
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability of testing the validity
    of a digital certificate by validating the date the certificate is being
    used is within the validity period for the certificate.

.. req::
    :id: R-39604
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability of testing the
    validity of a digital certificate by checking the Certificate Revocation
    List (CRL) for the certificates of that type to ensure that the
    certificate has not been revoked.

.. req::
    :id: R-75343
    :target: VNF
    :keyword: MUST
    :updated: casablanca

    The VNF **MUST** provide the capability of testing the
    validity of a digital certificate by recognizing the identity represented
    by the certificate - the "distinguished name".