SACM Working Group A. Montville Internet-Draft B. Munyan Intended status: Standards Track CIS Expires: 12 November 2020 11 May1,2020October 29, 2019Security Automation and Continuous Monitoring (SACM) Architecturedraft-ietf-sacm-arch-04draft-ietf-sacm-arch-05 Abstract This document defines an architecture enabling a cooperative Security Automation and Continuous Monitoring (SACM) ecosystem. This work is predicated upon information gleaned from SACM Use Cases and Requirements ([RFC7632] and [RFC8248] respectively), and terminology as found in [I-D.ietf-sacm-terminology]. WORKING GROUP: The source for this draft is maintained in GitHub. Suggested changes should be submitted as pull requests at https://github.com/sacmwg/ietf-mandm-sacm-arch/. Instructions are on that page as well. 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 onMay 1,12 November 2020. Copyright Notice Copyright (c)20192020 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)(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 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 . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 2. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 3 3. Architectural Overview . . . . . . . . . . . . . . . . . . .34 3.1. SACM Role-based Architecture . . . . . . . . . . . . . . 4 3.2. Architectural Roles/Components . . . . . . . . . . . . . 5 3.2.1. Orchestrator(s) . . . . . . . . . . . . . . . . . . .56 3.2.2. Repositories/CMDBs . . . . . . . . . . . . . . . . .56 3.2.3. Integration Service . . . . . . . . . . . . . . . . .56 3.3. Downstream Uses . . . . . . . . . . . . . . . . . . . . .67 3.3.1. Reporting . . . . . . . . . . . . . . . . . . . . . .67 3.3.2. Analytics . . . . . . . . . . . . . . . . . . . . . .67 3.4. Sub-Architectures . . . . . . . . . . . . . . . . . . . . 7 3.4.1. Collection Sub-Architecture . . . . . . . . . . . . . 7 3.4.2. Evaluation Sub-Architecture . . . . . . . . . . . . .910 4. Interactions . . . . . . . . . . . . . . . . . . . . . . . .11 5. Security Domain Workflows .12 4.1. Interaction Categories . . . . . . . . . . . . . . . . . 125.1. IT Asset Management4.1.1. Broadcast . . . . . . . . . . . . . . . . . . . . . . 125.1.1. Components, Capabilities and Workflow(s)4.1.2. Directed . . . . . . . . . . . . . . . . . . . . . . 135.2. Vulnerability4.2. Management Plane Functions . . . . . . . . . . . . . . . 13 4.2.1. Orchestrator Onboarding . . . . . . . . . . . . . . . 135.2.1. Components, Capabilities and Workflow(s)4.2.2. Component Onboarding . . . . . . . . . . . . . . . . 145.3. Configuration Management4.3. Component Interactions . . . . . . . . . . . . . . . . . 155.3.1. Components, Capabilities and Workflow(s)4.3.1. Initiate Ad-Hoc Collection . . . . . . . . . . . . . 15 4.3.2. Coordinate Periodic Collection . . . . . . . . . . . 15 4.3.3. Coordinate Observational/Event-based Collection . . . . . . . . . . . . . . . . . . . . . 166. Privacy Considerations4.3.4. Persist Collected Posture Attributes . . . . . . . . 16 4.3.5. Initiate Ad-Hoc Evaluation . . . . . . . . . . .18 7. Security Considerations. . 16 4.3.6. Queries . . . . . . . . . . . . . . . . .18 8. IANA Considerations. . . . . . 16 5. Taxonomy . . . . . . . . . . . . . . .18 9. References. . . . . . . . . . . 16 5.1. Orchestrator Registration . . . . . . . . . . . . . .19 9.1. Normative References. . 17 5.1.1. Topic . . . . . . . . . . . . . . . .19 9.2. Informative References. . . . . . . . 17 5.1.2. Interaction Type . . . . . . . . .19 Appendix A. Mapping to RFC8248. . . . . . . . . 17 5.1.3. Initiator . . . . . . . .21 Appendix B. Example Components. . . . . . . . . . . . . . 17 5.1.4. Request Payload . . .24 B.1. Policy Services. . . . . . . . . . . . . . . . 17 5.1.5. Receiver . . . . .24 B.2. Software Inventory. . . . . . . . . . . . . . . . . 17 5.1.6. Process Description . .25 B.3. Datastream Collection. . . . . . . . . . . . . . . 17 5.1.7. Response Payload . . .26 B.4. Network Configuration Collection. . . . . . . . . . . .26 Appendix C. Exploring An XMPP-based Solution. . . 18 5.1.8. Response Processing . . . . . . .27 C.1. Example Architecture using XMPP-Grid and Endpoint Posture Collection Protocol. . . . . . . . . . 18 5.2. Component Registration . . . . . . . . .30 Authors' Addresses. . . . . . . . 18 5.2.1. Topic . . . . . . . . . . . . . . .32 1. Introduction The purpose of this draft is to define an architectural approach for a SACM Domain, based on the spirit of use cases found in [RFC7632] and requirements found in [RFC8248]. This approach gains the most advantage by supporting a variety of collection systems, and intends to enable a cooperative ecosystem of tools from disparate sources with minimal operator configuration. 1.1. Requirements notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119, BCP 14 [RFC2119]. 2. Terms and Definitions This draft defers to [I-D.ietf-sacm-terminology] for terms and definitions. 3. Architectural Overview The generic approach proposed herein recognizes the need to obtain information from existing and future state collection systems, and makes every attempt to respect [RFC7632] and [RFC8248]. At the foundation of any architecture are entities, or components, that need to communicate. They communicate by sharing information, where, in a given flow, one or more components are consumers of information and one or more components are providers of information. +----------------+ | SACM Component | | (Provider) | +-------+--------+ | | +--------------v----------------+ | Integration Service | +--------------+----------------+ | | +-------v--------+ | SACM Component | | (Consumer) | +----------------+ Figure 1: Basic Architectural Structure A provider can be described as an abstraction that refers to an entity capable of sending SACM-relevant information to one or many consumers. Consumers can be described as an abstraction that refers to an entity capable of receiving SACM-relevant information from one or many providers. Different roles within a cooperative ecosystem may act as both providers and consumers of SACM-relevant information. 3.1. SACM Role-based Architecture Within the cooperative SACM ecosystem, a number of roles act in coordination to provide relevant policy/guidance, perform data collection, storage, evaluation, and support downstream analytics and reporting. +--------------------+ | Feeds/Repositories | | of External Data | +---------+----------+ | ******************************************* Boundary of Responsibility ****** | +-----------------+ | +--------------------+ | Orchestrator(s) | | | Repositories/CMDBs | +---------^-------+ | +----------^---------+ | | | +--------------------+ | | | | Downstream Uses | | | | | +----------------+ | +-----------v----------v-------------v------+ | | Analytics | | | Integration Service <------> +----------------+ | +-----------^--------------------------^----+ | +----------------+ | | | | | Reporting | | | | | +----------------+ | +-----------v-------------------+ | +--------------------+ | Collection Sub-Architecture | | +-------------------------------+ | +---------------v---------------+ | Evaluation Sub-Architecture | +-------------------------------+ Figure 2: Notional Role-based Architecture As shown in Figure 2, the SACM role-based architecture consists of some basic SACM Components communicating using an integration service. The integration service is expected to maximally align with the requirements described in [RFC8248], which means that the integration service will support brokered (i.e. point-to-point) and proxied data exchange. The boundary of responsibility is not intended to imply a physical boundary. Rather, it is intended to be inclusive of various cloud/ virtualized environments, BYOD and vendor-provided services in addition to any physical systems the enterprise operates. 3.2. Architectural Roles/Components This document suggests a variety of players in a cooperative ecosystem; these players are known as SACM Components. SACM Components may be composed of other SACM Components, and each SACM Component plays one, or more, of several roles relevant to the ecosystem. Roles may act as providers of information, consumers of information, or both provider and consumer. Figure 2 depicts a number of SACM components which are architecturally significant and therefore warrant discussion and clarification. 3.2.1. Orchestrator(s) Orchestration components exists to aid in the automation of configuration, coordination, and management for the ecosystem of SACM components. The Orchestrator performs control-plane operations, administration of an implementing organization's components (including endpoints, posture collection services, and downstream activities), scheduling of automated tasks, and any ad-hoc activities such as the initiation of collection or evaluation activities. The Orchestrator is the key administrative interface into the SACM architecture. 3.2.2. Repositories/CMDBs Figure 2 only includes a single reference to "Repositories/CMDBs", but in practice, a number of separate data repositories may exist, including posture attribute repositories, policy repositories, local vulnerability definition data repositories, and state assessment results repositories. These data repositories may exist separately or together in a single representation, and the design of these repositories may be as distinct as their intended purpose, such as the use of relational database management systems or graph/map implementations focused on the relationships between data elements. Each implementation of a SACM repository should focus on the relationships between data elements and implement the SACM information and data model(s). 3.2.3. Integration Service If each SACM component represents a set of capabilities, the Integration Service represents the "fabric" by which all those services are woven together. The Integration Service acts as a message broker, combining a set of common message categories and infrastructure to allow SACM components to communicate using a shared set of interfaces. The Integration Service's brokering capabilities enable the exchange of various information payloads, orchestration of component capabilities, message routing and reliable delivery. The Integration Service minimizes the dependencies from one system to another through the loose coupling of applications through messaging. SACM components will "attach" to the Integration Service either through native support for the integration implementation, or through the use of "adapters" which provide a proxied attachment. The Integration Service should provide mechanisms for synchronous "request/response"-style messaging, asynchronous "send and forget" messaging, or publish/subscribe. It is the responsibility of the Integration Service to coordinate and manage the sending and receiving of messages. The Integration Service should allow components the ability to directly connect and produce or consume messages, or connect via message translators which can act as a proxy, transforming messages from a component format to one implementing a SACM data model. The Integration Service MUST provide routing capabilities for payloads between producers and consumers. The Integration Service MAY provide further capabilities within the payload delivery pipeline. Examples of these capabilities include, but are not limited to, intermediate processing, message transformation, type conversion, validation, etc. 3.3. Downstream Uses As depicted by Figure 2, a number of downstream uses exist in the cooperative ecosystem. Each notional SACM component represents distinct sub-architectures which will exchange information via the integration services, using interactions described in this draft. 3.3.1. Reporting The Reporting component represents capabilities outside of the SACM architecture scope dealing with the query and retrieval of collected posture attribute information, evaluation results, etc. in various display formats that are useful to a wide range of stakeholders. 3.3.2. Analytics The Analytics component represents capabilities outside of the SACM architecture scope dealing with the discovery, interpretation, and communication of any meaningful patterns of data in order to inform effective decision making within the organization. 3.4. Sub-Architectures Figure 2 shows two components representing sub-architectural roles involved in a cooperative ecosystem of SACM components: Collection and Evaluation. 3.4.1. Collection Sub-Architecture The Collection sub-architecture, in a SACM context, is the mechanism by which posture attributes are collected from applicable endpoints and persisted to a repository, such as a configuration management database (CMDB). Orchestration components will choreograph endpoint data collection via interactions using the Integration Service as a message broker. Instructions to perform endpoint data collection are directed to a Posture Collection Service capable of performing collection activities utilizing any number of methods, such as SNMP, NETCONF/RESTCONF, SSH, WinRM, or host-based. +----------------------------------------------------------+ | Orchestrator(s) | +-----------+----------------------------------------------+ | +------------------------------+ | | Posture Attribute Repository | | +--------------^---------------+ Perform | Collection | | Collected Data | ^ | | +-----------v------------------------------+---------------+ | Integration Service | +----+------------------^-----------+------------------^---+ | | | | v | v | Perform Collected Perform Collected Collection Data Collection Data | ^ | ^ | | | | +----v-----------------------+ +----v------------------+------+ | Posture Collection Service | | Endpoint | +---^------------------------+ | +--------------------------+ | | | | |Posture Collection Service| | | v | +--------------------------+ | Events Queries +------------------------------+ ^ | | | +---+-------------------v----+ | Endpoint | +----------------------------+ Figure 3: Decomposed Collection Sub-Architecture 3.4.1.1. Posture Collection Service The Posture Collection Service (PCS) is the SACM component responsible for the collection of posture attributes from an endpoint or set of endpoints. A single PCS may be responsible for management of posture attribute collection from many endpoints. The PCS will interact with the Integration Service to receive collection instructions and to provide collected posture data for persistence to the Posture Attribute Repository. Collection instructions may be supplied in a variety of forms, including subscription to a publish/ subscribe topic to which the Integration Service has published instructions, via request/response-style synchronous messaging, or via asynchronous "send-and-forget" messaging. Collected posture information may then be supplied to the Integration Service via similar channels. The various interaction types are discussed later in this draft (TBD). 3.4.1.2. Endpoint Building upon [I-D.ietf-sacm-terminology], the SACM Collection Sub- Architecture augments the definition of an Endpoint as a component within an organization's management domain from which a Posture Collection Service will collect relevant posture attributes. 3.4.1.3. Posture Attribute Repository The Posture Attribute Repository is a SACM component responsible for the persistent storage of posture attributes collected via interactions between the Posture Collection Service and Endpoints. 3.4.1.4. Posture Collection Workflow Posture collection may be triggered from a number of components, but commonly begin either via event-based triggering on an endpoint or through manual orchestration, both illustrated in Figure 3 above. Once orchestration has provided the directive to perform collection, posture collection services consume the directives. Posture collection is invoked for those endpoints overseen by the respective posture collection services. Collected data is then provided to the Integration Service, with a directive to store that information in an appropriate repository. 3.4.2. Evaluation Sub-Architecture The Evaluation Sub-Architecture, in the SACM context, is the mechanism by which policy, expressed in the form of expected state, is compared with collected posture attributes to yield an evaluation result, that result being contextually dependent on the policy being evaluated. +------------------+ | Collection | +-------------------------------+ | Sub-Architecture | | Evaluation Results Repository | +--------------+ +--------^---------+ +-----------------^-------------+ | Orchestrator | | | +------+-------+ | | | Perform Store Evaluation Results Perform. . . . . . . . . 18 5.2.2. Interaction Type . . . . . . . . . . . . . . . . . . 18 5.2.3. Initiator . . . . . . . . . . . . . . . . . . . . . . 18 5.2.4. Request Payload . . . . . . . . . . . . . . . . . . . 18 5.2.5. Receiver . . . . . . . . . . . . . . . . . . . . . . 18 5.2.6. Process Description . . . . . . . . . . . . . . . . . 19 5.2.7. Response Payload . . . . . . . . . . . . . . . . . . 19 5.2.8. Response Processing . . . . . . . . . . . . . . . . . 19 5.3. Orchestrator-to-Component Administrative Interface . . . 19 5.3.1. Capability Advertisement Handshake . . . . . . . . . 19 5.3.2. Directed Collection| Evaluation | | | | | +------v----------------------v--------------------------------+-------------+ | Integration Service | +--------+----------------------------^----------------------^---------------+ | | | | | | Perform Retrieve Posture | Evaluation Attributes Retrieve Policy | | | | | | +--------v-------------------+ +-----v------+ +------v-----+ | Posture Evaluation Service | | Posture | | Policy | +----------------------------+ | Attribute | | Repository | | Repository | +------------+ +------------+ Figure 4: Decomposed Evaluation Sub-Architecture 3.4.2.1. Posture Evaluation Service The Posture Evaluation Service (PES) represents the SACM component responsible for coordinating the policy to be evaluated. . . . . . . . . . . . . . . . . 20 5.4. [Taxonomy Name] . . . . . . . . . . . . . . . . . . . . . 20 5.4.1. Topic . . . . . . . . . . . . . . . . . . . . . . . . 21 6. Privacy Considerations . . . . . . . . . . . . . . . . . . . 21 7. Security Considerations . . . . . . . . . . . . . . . . . . . 21 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 21 9.1. Normative References . . . . . . . . . . . . . . . . . . 21 9.2. Informative References . . . . . . . . . . . . . . . . . 22 Appendix A. Security Domain Workflows . . . . . . . . . . . . . 24 A.1. IT Asset Management . . . . . . . . . . . . . . . . . . . 24 A.1.1. Components, Capabilities andthe collected posture attributes relevant to that policy, as well as the comparison engine responsible for correctly determining compliance with the expected state. 3.4.2.2. Policy Repository The Policy Repository represents a persistent storage mechanism for the policy to be assessed against collected posture attributes to determine if an endpoint meets the defined expected state. Examples of information contained in a Policy Repository would beWorkflow(s) . . . . . . 24 A.2. VulnerabilityDefinition Data or configuration recommendations as part of a CIS Benchmark or DISA STIG. 3.4.2.3. Evaluation Results RepositoryManagement . . . . . . . . . . . . . . . . 25 A.2.1. Components, Capabilities and Workflow(s) . . . . . . 26 A.3. Configuration Management . . . . . . . . . . . . . . . . 26 A.3.1. Components, Capabilities and Workflow(s) . . . . . . 27 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29 1. Introduction TheEvaluation Results Repository persists the information representing the resultspurpose ofa particular posture assessment, indicating those posture attributes collected from various endpoints which either meet or do not meet the expected state defined by the assessed policy. Consideration should be madethis draft is to define an architectural approach for a SACM Domain, based on thecontextspirit ofindividual results. For example, meetinguse cases found in [RFC7632] and requirements found in [RFC8248]. This approach gains theexpected state for a configuration attribute indicatesmost advantage by supporting acorrect configurationvariety ofthe endpoint, whereas meeting an expected state for a vulnerable software version indicates an incorrectcollection systems, andtherefore vulnerable configuration. 3.4.2.4. Posture Evaluation Workflow Posture evaluation is orchestrated through the Integration Serviceintends tothe appropriate Posture Evaluation Service. The PES will, through coordinationenable a cooperative ecosystem of tools from disparate sources withthe Integration Service, query both the Posture Attribute Repository and the Policy Repository to obtain relevant state data for comparison. If necessary, the PES may be required to invoke further posture collection. Once all relevant posture information has been collected, it is compared to expected state based on applicable policy. Comparison results are then persisted to an evaluation results repository for further downstream useminimal operator configuration. 1.1. Requirements notation The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", andanalysis. 4. Interactions SACM Components"OPTIONAL" in this document areintendedtointeract with other SACM Components. These interactions canbethought of, at the architectural level,interpreted asthe combination of interfaces with their supported operations. Each interaction will convey a payload of information.described in RFC 2119, BCP 14 [RFC2119]. 2. Terms and Definitions This draft defers to [I-D.ietf-sacm-terminology] for terms and definitions. 3. Architectural Overview Thepayloadgeneric approach proposed herein recognizes the need to obtain informationis expectedfrom existing and future state collection systems, and makes every attempt tocontain sub-domain-specific characteristicsrespect [RFC7632] andinstructions. Two categories of interactions SHOULD be supported by[RFC8248]. At theIntegration Service; broadcast interactions, and directed interactions. o *Broadcast*: A broadcast interaction, commonly known as "publish/ subscribe", allows for a wider distributionfoundation ofa message payload. When a payload is publishedany architecture are entities, or components, that need to communicate. They communicate by sharing information, where, in atopic on the Integration Service, all subscribers to that topicgiven flow, one or more components arealertedconsumers of information andmay consume the message payload. A broadcast interaction may also simulate a "directed" interaction when a topic only has a single subscriber. An exampleone or more components are providers ofa broadcast interaction couldinformation. +----------------+ | SACM Component | | (Provider) | +-------+--------+ | | +--------------v----------------+ | Integration Service | +--------------+----------------+ | | +-------v--------+ | SACM Component | | (Consumer) | +----------------+ Figure 1: Basic Architectural Structure A provider can beto publish to a topicdescribed as an abstraction thatnew configuration assessment content is available. Subscribing consumers receive the notification, and proceedrefers tocollect endpoint configuration posture based on the new content. o *Directed*: The intentan entity capable ofa directed interaction issending SACM-relevant information to one or many consumers. Consumers can be described as an abstraction that refers toenable point-to-point communications betweenan entity capable of receiving SACM-relevant information from one or many providers. Different roles within aproducercooperative ecosystem may act as both providers andconsumer, through the standard interfaces provided byconsumers of SACM-relevant information. 3.1. SACM Role-based Architecture Within theIntegration Service. The provider component indicates which consumer is intendedcooperative SACM ecosystem, a number of roles act in coordination toreceive the payload,provide relevant policy/guidance, perform data collection, storage, evaluation, andthesupport downstream analytics and reporting. +-----------------+ +--------------------+ | Orchestrator(s) | | Repositories/CMDBs | +---------^-------+ +----------^---------+ | | +--------------------+ | | | Downstream Uses | | | | +----------------+ | +-----------v------------------------v------+ | | Analytics | | | Integration Serviceroutes<------> +----------------+ | +-----------^--------------------------^----+ | +----------------+ | | | | | Reporting | | | | | +----------------+ | +-----------v-------------------+ | +--------------------+ | Collection Sub-Architecture | | +-------------------------------+ | +---------------v---------------+ | Evaluation Sub-Architecture | +-------------------------------+ Figure 2: Notional Role-based Architecture As shown in Figure 2, thepayload directly to that consumer. Two "styles"SACM role-based architecture consists ofdirected interaction exist, differing only by the response fromsome basic SACM Components communicating using an integration service. The integration service is expected to maximally align with thepayload consumer: * *Synchronous (Request/Response)*: Synchronous, request/response style interaction requiresrequirements described in [RFC8248], which means that therequesting component blockintegration service will support brokered (i.e. point-to-point) andwait for the receiving component to respond, or to time out when that response is delayed pastproxied data exchange. 3.2. Architectural Roles/Components This document suggests a variety of players in agiven time threshold. A synchronous interaction examplecooperative ecosystem; known as SACM Components. SACM Components may bequerying a CMDB for posture attribute information in ordercomposed of other SACM Components, and each SACM Component plays one, or more, of several roles relevant toperform an evaluation. * *Asynchronous (Fire-and-Forget)*: An asynchronous interaction involves the payload producer directingthemessage to a consumer, but not blockingecosystem. Roles may act as providers of information, consumers of information, orwaiting forboth provider and consumer. Figure 2 depicts aresponse. This stylenumber ofinteraction allows the producer to continue onSACM components which are architecturally significant and therefore warrant discussion and clarification. 3.2.1. Orchestrator(s) Orchestration components exists toother activities withoutaid in theneed to waitautomation of configuration, coordination, and management forresponses. This style is particularly useful whentheinteraction payload invokes a potentially long-running task,ecosystem of SACM components. The Orchestrator performs control-plane operations, administration of an implementing organization's components (including endpoints, posture collection services, and downstream activities), scheduling of automated tasks, and any ad-hoc activities such asdata collection, report generation,the initiation of collection orpolicy evaluation.evaluation activities. Thereceiving component may reply later via callbacks or further interactions, but itOrchestrator isnot mandatory. Each interaction will conveythe key administrative interface into the SACM architecture. 3.2.2. Repositories/CMDBs Figure 2 only includes apayload of information. The payload is expectedsingle reference tocontain specific characteristics"Repositories/CMDBs", but in practice, a number of separate data repositories may exist, including posture attribute repositories, policy repositories, local vulnerability definition data repositories, and state assessment results repositories. These data repositories may exist separately or together in a single representation, andinstructions to be interpreted by receiving components. 5. Security Domain Workflows This section describes three primary information security domains from which workflowsthe design of these repositories may bederived: IT Asset Management, Vulnerability Management, and Configuration Management. 5.1. IT Asset Management Information Technology assetas distinct as their intended purpose, such as the use of relational database managementis easier said than done. The [CISCONTROLS] have two controls dealing with IT asset management. Control 1, Inventory and Controlsystems or graph/map implementations focused on the relationships between data elements. Each implementation ofHardware Assets, states, "Actively manage (inventory, track, and correct) all hardware devicesa SACM repository should focus on thenetwork so that only authorized devices are given access,relationships between data elements andunauthorizedimplement the SACM information andunmanaged devicesdata model(s). 3.2.3. Integration Service If each SACM component represents a set of capabilities, the Integration Service represents the "fabric" by which all those services arefound and prevented from gaining access." Control 2, Inventory and Controlwoven together. The Integration Service acts as a message broker, combining a set ofSoftware Assets, states, "Actively manage (inventory, track,common message categories andcorrect) all software oninfrastructure to allow SACM components to communicate using a shared set of interfaces. The Integration Service's brokering capabilities enable thenetwork so that only authorized software is installed and can execute, and that unauthorized and unmanaged software is foundexchange of various information payloads, orchestration of component capabilities, message routing andpreventedreliable delivery. The Integration Service minimizes the dependencies frominstallation or execution." In spirit, this covers all ofone system to another through theprocessing entities on your network (as opposedloose coupling of applications through messaging. SACM components will "attach" tothings like network cables, dongles, adapters, etc.), whether physical or virtual, on-premisesthe Integration Service either through native support for the integration implementation, orinthrough thecloud. 5.1.1. Components, Capabilitiesuse of "adapters" which provide a proxied attachment. The Integration Service should provide mechanisms for both synchronous andWorkflow(s) TBD 5.1.1.1. Components TBD 5.1.1.2. Capabilities An IT asset management capability needs to be able to: o Identifyasynchronous "request/response"-style messaging, andcatalog new assets by executing Target Endpoint Discovery Tasks o Provide information about its managed assets, including uniquely identifying information (for that enterprise) o Handle software and/or hardware (including virtual assets) o Represent cloud hybrid environments 5.1.1.3. Workflow(s) TBD 5.2. Vulnerability Management Vulnerability management isarelatively established process. To paraphrase the [CISCONTROLS], continuous vulnerability managementpublish/subscribe mechanism to implement event-based messaging. It is theactresponsibility ofcontinuously acquiring, assessing, and taking subsequent action on new information in orderthe Integration Service toidentifycoordinate andremediate vulnerabilities, therefore minimizingmanage thewindowsending and receiving ofopportunity for attackers. A vulnerability assessment (i.e. vulnerability detection) is performed in two steps: o Endpoint information collected bymessages. The Integration Service should allow components theendpoint managementability to directly connect and produce or consume messages, or connect via message translators which can act as a proxy, transforming messages from a component format to one implementing a SACM data model. The Integration Service MUST provide routing capabilities for payloads between producers and consumers. The Integration Service MAY provide further capabilitiesis examined bywithin thevulnerability managementpayload delivery pipeline. Examples of these capabilitiesthrough Evaluation Tasks. o If the data possessedinclude, but are not limited to, intermediate processing, message transformation, type conversion, validation, or other enterprise integration patterns. 3.3. Downstream Uses As depicted bythe endpoint management capabilities is insufficient,Figure 2, aCollection Task is triggered and the necessary data is collected fromnumber of downstream uses exist in thetarget endpoint. Vulnerability detection relies oncooperative ecosystem. Each notional SACM component represents distinct sub-architectures which will exchange information via theexaminationintegration services, using interactions described in this draft. 3.3.1. Reporting The Reporting component represents capabilities outside ofdifferent endpoint information depending onthenatureSACM architecture scope dealing with the query and retrieval ofa specific vulnerability. Common endpoint information usedcollected posture attribute information, evaluation results, etc. in various display formats that are useful todetectavulnerability includes: o A specific software version is installed onwide range of stakeholders. 3.3.2. Analytics The Analytics component represents capabilities outside of theendpoint o File system attributes o Specific state attributes In some cases,SACM architecture scope dealing with theendpoint information neededdiscovery, interpretation, and communication of any meaningful patterns of data in order todetermine an endpoint's vulnerability status will have been previously collected byinform effective decision making within theendpoint management capabilities and availableorganization. 3.4. Sub-Architectures Figure 2 shows two components representing sub-architectural roles involved in aRepository. However, in other cases, the necessary endpoint information will not be readily availablecooperative ecosystem of SACM components: Collection and Evaluation. 3.4.1. Collection Sub-Architecture The Collection sub-architecture is, in aRepositorySACM context, the mechanism by which posture attributes are collected from applicable endpoints and persisted to aCollection Taskrepository, such as a configuration management database (CMDB). Orchestration components willbe triggered to performchoreograph endpoint data collectionfromvia defined interactions, using thetarget endpoint. Of course, some implementations of endpoint management capabilities may prefer to enable operatorsIntegration Service as a message broker. Instructions to performthis collection even when sufficient information can be provided by theendpointmanagement capabilities (e.g. there may be freshness requirements for information). 5.2.1. Components, Capabilities and Workflow(s) TBD 5.2.1.1. Components TBD 5.2.1.2. Capabilities TBD 5.2.1.3. Workflow(s) TBD 5.3. Configuration Management Configuration management involves configuration assessment, which requires state assessment. The [CISCONTROLS] specify two high-level controls concerning configuration management (Control 5 for non- network devices and Control 11data collection are directed to a Posture Collection Service capable of performing collection activities utilizing any number of methods, such as SNMP, NETCONF/RESTCONF, SSH, WinRM, packet capture, or host- based. +----------------------------------------------------------+ | Orchestrator(s) | +-----------+----------------------------------------------+ | +------------------------------+ | | Posture Attribute Repository | | +--------------^---------------+ Perform | Collection | | Collected Data | ^ | | +-----------v------------------------------+---------------+ | Integration Service | +----+------------------^-----------+------------------^---+ | | | | v | v | Perform Collected Perform Collected Collection Data Collection Data | ^ | ^ | | | | +----v-----------------------+ +----|------------------|------+ | Posture Collection Service | | | Endpoint | | +---^------------------------+ | +--v------------------+----+ | | | | |Posture Collection Service| | | v | +--------------------------+ | Events Queries +------------------------------+ ^ | (PCS resides on Endpoint) | | +---+-------------------v----+ | Endpoint | +----------------------------+ (PCS does not reside on Endpoint) Figure 3: Decomposed Collection Sub-Architecture 3.4.1.1. Posture Collection Service The Posture Collection Service (PCS) is the SACM component responsible fornetwork devices). Asthe collection of posture attributes from anaside, these controls are listed separately because many enterprises have different organizationsendpoint or set of endpoints. A single PCS may be responsible formanaging network infrastructure and workloadmanagement of posture attribute collection from many endpoints.Merging the two controls results inThe PCS will interact with thefollowing paraphrasing: Establish, implement,Integration Service to receive collection instructions andactively manage (track, report on, correct)to provide collected posture data for persistence to thesecurity configuration of systems using a rigorous configuration management and change control processPosture Attribute Repository. Collection instructions may be supplied inordera variety of forms, including subscription toprevent attackers from exploiting vulnerable services and settings. Typically, an enterprise will use configuration guidance fromareputable source, and from timepublish/ subscribe topic totime they may tailorwhich theguidance from that source prior to adopting itIntegration Service has published instructions, or via request/response-style messaging (either synchronous or asynchronous). Four classifications of posture collections MAY be supported. 3.4.1.1.1. Ad-Hoc Ad-Hoc collection is defined asparta single colletion oftheir enterprise standard. The enterprise standardposture attributes, collected at a particular time. An example of ad-hoc collection isthen provided totheappropriate configuration assessment tools and they assess endpoints and/or appropriate endpoint information. A preferred flow follows: o Reputable source publishes new or updated configuration guidance o Enterprise configuration assessment capability retrieves configuration guidance from reputable source o Optional: Configuration guidancesingle collection of a specific registry key. 3.4.1.1.2. Continuous/Scheduled Continuous/Scheduled collection is defined as the ongoing, periodic collection of posture attributes. An example of scheduled collection is the collection of a specific registry key value every day at a given time. 3.4.1.1.3. Observational This classification of collection istailoredtriggered by the observation, external to an endpoint, of information asserting posture attribute values forenterprise-that endpoint. An example of observational collection is examination of netflow data for particular packet captures and/or specificneeds o Configuration assessment tool queries asset inventory repositoryinformation within those captures. 3.4.1.1.4. Event-based Event-based collection may be triggered either internally or externally toretrievethe endpoint. Internal event-based collection is triggered when alistposture attribute ofaffected endpoints o Configuration assessment tool queries configuration state repository to evaluate compliance o If informationinterest isstaleadded, removed, orunavailable, configuration assessment tool triggersmodified on anad hoc assessment The SACM architecture needs to support varying deployment models to accommodateendpoint. This modification indicates a change in the current state of theindustry, but should strongly encourage event-driven approachesendpoint, potentially affecting its adherence tomonitoring configuration. 5.3.1. Components, Capabilities and Workflow(s) This section provides more detail about the components and capabilities required when consideringsome defined policy. Modification of theaforementioned configuration management workflow. 5.3.1.1. Components The followingendpoint's minimum password length isa minimal listan example ofSACM Components requiredan attribute change which could trigger collection. External event-based collection can be described as a collector being subscribed toimplement the aforementioned configuration assessment workflow. o Configuration Policy Feed: Anan external source ofauthoritative configuration recommendations. o Configuration Policy Repository:information, receiving events from that external source on a periodic or continuous basis. Aninternal repositoryexample ofenterprise standard configurations. o Configuration Assessment Orchestrator: Aevent-based collection is subscription to YANG Push notifications. 3.4.1.2. Endpoint Building upon [I-D.ietf-sacm-terminology], the SACM Collection Sub- Architecture augments the definition of an Endpoint as a componentresponsible for orchestrating assessments. owithin an organization's management domain from which a Posture Collection Service will collect relevant posture attributes. 3.4.1.3. Posture AttributeCollection Subsystem: ARepository The Posture Attribute Repository is a SACM component responsible forcollectionthe persistent storage of posture attributesfrom systems. ocollected via interactions between the PostureAttribute Repository: A component used for storing system posture attribute values. o Configuration Assessment Evaluator: A component responsible for evaluating system posture attribute values against expected posture attribute values. o Configuration Assessment Results Repository: A component used for storing evaluation results. 5.3.1.2. Capabilities Per [RFC8248], solutions MUST support capability negotiation. Components implementing specific interfacesCollection Service andoperations (i.e. interactions) will needEndpoints. 3.4.1.4. Posture Collection Workflow Posture collection may be triggered from amethodnumber ofdescribing their capabilities to other components participatingcomponents, but commonly begin either via event-based triggering on an endpoint or through manual orchestration, both illustrated in Figure 3 above. Once orchestration has provided theecosystem;directive to perform collection, posture collection services consume the directives. Posture collection is invoked forexample, "Asthose endpoints overseen by the respective posture collection services. Collected data is then provided to the Integration Service, with acomponentdirective to store that information in an appropriate repository. 3.4.2. Evaluation Sub-Architecture The Evaluation Sub-Architecture, in theecosystem, I can assess the configuration of Windows, MacOS, and AWS using OVAL". 5.3.1.3. Configuration Assessment Workflow This section describesSACM context, is thecomponents and interactionsmechanism by which policy, expressed ina basic configuration assessment workflow. For simplicity, error conditions are recognized as being necessary and are not depicted. When one component messages another component,themessage isform of expectedto be handled appropriately unless therestate, is compared with collected posture attributes to yield anerror condition, or other notification, messaged in return. +-------------+ +----------------+evaluation result, that result being contextually dependent on the policy being evaluated. +------------------++------------+ | Policy Feed | | Orchestrator | | Evaluation| Collection |Evaluation | +------+------+ +-------+--------++-------------------------------+ | Sub-Architecture | | Evaluation Results| | | +---^----------+---+ |Repository | +--------------+ +--------^---------+ +-----------------^-------------+ | Orchestrator | | |+------^-----+ | | | | | 1.| 3.| 8.| 9.| 10.| | |+------+-------+ (Potentially) | | Perform Store Evaluation Results Perform Collection | Evaluation | | | | |+------v-----------------v---------------+----------v-------------+-----++------v----------------------v--------------------------------+-------------+ | Integration Service |+-----+----------------------------------+----------^---------+------^--+ | | | |+--------^----------------------^-----------------------^--------------------+ | | | | | |2.| 4.| 5.| 6.| 7.| | | || Retrieve Posture Perform Retrieve Policy Attributes Evaluation | | | | | | +------v-----+ +-----v------++---v----------+---+ +--v------+--++--------v-------------------+ | Policy | |CollectionPosture | | Posture Evaluation Service | | Repository | |Sub-Architecture | |Attribute | +----------------------------+ +------------++------------------+| Repository | +------------+ Figure5: Configuration Assessment Component Interactions Figure 5 depicts4: Decomposed Evaluation Sub-Architecture 3.4.2.1. Posture Evaluation Service The Posture Evaluation Service (PES) represents the SACM component responsible for coordinating the policy to be evaluated and the collected posture attributes relevant to that policy, as well as the comparison engine responsible for correctly determining compliance with the expected state. 3.4.2.2. Policy Repository The Policy Repository represents a persistent storage mechanism for the policy to be assessed against collected posture attributes to determine if an endpoint meets the desired expected state. Examples of information contained in a Policy Repository would be Vulnerability Definition Data or configuration recommendations as part of a CIS Benchmark or DISA STIG. 3.4.2.3. Evaluation Results Repository The Evaluation Results Repository persists the information representing the results of a particular posture assessment, indicating those posture attributes collected from various endpoints which either meet or do not meet the expected state defined by the assessed policy. Consideration should be made for the context of individual results. For example, meeting the expected state for a configurationassessment components and their interactions, which are further described below. 1. A policy feed providesattribute indicates a correct configurationassessment policy payload toof the endpoint, whereas meeting an expected state for a vulnerable software version indicates an incorrect configuration. 3.4.2.4. Posture Evaluation Workflow Posture evaluation is orchestrated through the IntegrationService. 2.Service to the appropriate Posture Evaluation Service (PES). ThePolicy Repository, a consumer of Policy Feed information, receivesPES will, using interactions defined by the applicable taxonomy, query both the Posture Attribute Repository andpersiststhe PolicyFeed's payload. 3. Orchestration component(s), either manually invoked, scheduled, or event-based, publish a payloadRepository tobegin the configuration assessment process. 4.obtain relevant state data for comparison. If necessary,Collection Sub-Architecture componentsthe PES may beinvokedrequired tocollect neeededinvoke further postureattribute information. 5. If necessary,collection. Once all relevant posture information has been collected, it is compared to expected state based on applicable policy. Comparison results are then persisted to an evaluation results repository for further downstream use and analysis. 4. Interactions SACM Components are intended to interact with other SACM Components. These interactions can be thought of, at theCollection Sub-Architecturearchitectural level, as the combination of interfaces with their supported operations. Each interaction willprovide collected posture attributesconvey a payload of information. The payload information is expected to contain sub-domain-specific characteristics and/or instructions. 4.1. Interaction Categories Two categories of interactions SHOULD be supported by the Integration Service; broadcast and directed. 4.1.1. Broadcast A broadcast interaction, commonly known as "publish/subscribe", allows for a wider distribution of a message payload. When a payload is published to a topic on the IntegrationService for persistenceService, all subscribers tothe Posture Attribute Repository. 6. The Posture Attribute Repository willthat topic are alerted and may consume the message payload. This category of interaction can also be described as a "unicast" interaction when a topic only has a single subscriber. An example of a broadcast interaction could be to publish Linux OVAL objects to apayload querying for relevantpostureattribute information. 7. The Posture Attribute Repository will providecollection topic. Subscribing consumers receive therequested informationnotification, and proceed to collect endpoint configuration posture based on theIntegration Service, allowing further orchestration payloads requesting the Evaluation Sub- Architecture perform evaluation tasks. 8.new content. 4.1.2. Directed TheEvaluation Sub-Architecture consumes the evaluation payload and performs component-specific state comparison operationsintent of a directed interaction is toproduce evaluation results. 9. A payload containing evaluation results areenable point-to-point communications between a producer and consumer, through the standard interfaces provided by theEvaluation Sub-Architecture to theIntegrationService 10. Evaluation results are consumed by/persistedService. The provider component indicates which consumer is intended to receive theEvaluation Results Repository Inpayload, and theabove flow,Integration Service routes the payloadinformation is expecteddirectly toconvey the context requiredthat consumer. Two "styles" of directed interaction exist, differing only by thereceivingresponse from the payload consumer. 4.1.2.1. Synchronous Synchronous, request/response style interaction requires that the requesting component block and wait for theaction being taken under different circumstances. For example, a directed message sent from an Orchestratorreceiving component to respond, or to time out when that response is delayed past aCollection sub-architecture mightgiven time threshold. A synchronous interaction example may betelling that Collector to watchquerying aspecificCMDB for posture attributeand report only specific detected changesinformation in order to perform an evaluation. 4.1.2.2. Asynchronous An asynchronous interaction involves thePosture Attribute Repository, or it might be tellingpayload producer directing theCollector to gather that posture attribute immediately. Such details are expectedmessage tobe handled as part of that payload,a consumer, but notas partblocking or waiting for an immediate response. This style of interaction allows thearchitecture described herein. 6. Privacy Considerations TODO 7. Security Considerations TODO 8. IANA Considerations TODO: Revamp this section afterproducer to continue on to other activities without theconfiguration assessment workflow is fleshed out. IANA tables can probably be usedneed tomake lifewait for responses. This style is particularly useful when the interaction payload invokes alittle easier. We would likepotentially long-running task, such as data collection, report generation, or policy evaluation. The receiving component may reply later via callbacks or further interactions, but it is not mandatory. 4.2. Management Plane Functions Mangement plane functions describe aplacecomponent's interactions with the ecosystem itself, not necessarily relating toenumerate: o Capability/operation semantics o SACM Component implementation identifiers o SACM Component versions o Associations of SACM Components (and versions)collection, evaluation, or downstream analytical processes. 4.2.1. Orchestrator Onboarding The Orchestrator component, being a specialized role in the architecture, onboards tospecific Capabilities o Collection sub-architecture Identification 9. References 9.1. Normative References [I-D.ietf-sacm-ecp] Haynes, D., Fitzgerald-McKay, J., and L. Lorenzin, "Endpoint Posture Collection Profile", draft-ietf-sacm- ecp-05 (workthe ecosystem inprogress), June 2019. [RFC2119] Bradner, S., "Key words for usesuch a manner as to enable the onboarding and capabilities of the other component roles. The Orchestrator must be enabled with the set of capabilities needed to manage the functions of the ecosystem. With this inRFCsmind, the Orchestrator must first authenticate toIndicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc2119>. [RFC8412] Schmidt, C., Haynes, D., Coffin, C., Waltermire, D., and J. Fitzgerald-McKay, "Software Inventory Message and Attributes (SWIMA) for PA-TNC", RFC 8412, DOI 10.17487/RFC8412, July 2018, <https://www.rfc-editor.org/info/rfc8412>. [RFC8600] Cam-Winget, N., Ed., Appala, S., Pope, S., and P. Saint- Andre, "Using Extensible Messagingthe Integration Service. Once authentication has succeeded, the Orchestrator must establish "service handlers" per the Section 5.2. Once "service handlers" have been established, the Orchestrator is then equipped to handle component registration, onboarding, capability discovery, andPresence Protocol (XMPP)topic subscription policy. The following requirements exist forSecurity Information Exchange", RFC 8600, DOI 10.17487/RFC8600, June 2019, <https://www.rfc-editor.org/info/rfc8600>. 9.2. Informative References [CISCONTROLS] "CIS Controls v7.0", n.d., <https://www.cisecurity.org/controls>. [draft-birkholz-sacm-yang-content] Birkholz, H. and N. Cam-Winget, "YANG subscribed notifications via SACM Statements", n.d., <https://tools.ietf.org/html/draft-birkholz-sacm-yang- content-01>. [HACK100] "IETF 100 Hackathon - Vulnerability Scenario EPCP+XMPP", n.d., <https://www.github.com/sacmwg/vulnerability- scenario/ietf-hackathon>. [HACK101] "IETF 101 Hackathon - Configuration Assessment XMPP", n.d., <https://www.github.com/CISecurity/Integration>. [HACK102] "IETF 102 Hackathon - YANG Collection on Traditional Endpoints", n.d., <https://www.github.com/CISecurity/YANG>. [HACK103] "IETF 103 Hackathon - N/A", n.d., <https://www.ietf.org/how/meetings/103/>. [HACK104] "IETF 104 Hackathon - A simple XMPP client", n.d., <https://github.com/CISecurity/SACM-Architecture>. [HACK105] "IETF 105 Hackathon - A more robust XMPP client including collection extensions", n.d., <https://github.com/CISecurity/SACM-Architecture>. [HACK99] "IETF 99 Hackathonthe Orchestrator to establish "service handlers" supporting the Section 5.2: -Vulnerability Scenario EPCP", n.d., <https://www.github.com/sacmwg/vulnerability-scenario/ ietf-hackathon>. [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-16 (work in progress), December 2018. [NIST800126] Waltermire, D., Quinn, S., Booth, H., Scarfone, K., and D. Prisaca, "SP 800-126 Rev. 3The Orchestrator MUST enable the capability to receive onboarding requests via the "/orchestrator/registration" topic, - TheTechnical Specification forOrchestrator MUST have theSecurity Content Automation Protocol (SCAP) - SCAP Version 1.3", February 2018, <https://csrc.nist.gov/publications/detail/sp/800-126/rev- 3/final>. [NISTIR7694] Halbardier, A., Waltermire, D.,capability to generate, manage, andM. Johnson, "NISTIR 7694 Specificationpersist unique identifiers forAsset Reporting Format 1.1", n.d., <https://csrc.nist.gov/publications/detail/nistir/7694/ final>. [RFC5023] Gregorio, J., Ed. and B. de hOra, Ed., "The Atom Publishing Protocol", RFC 5023, DOI 10.17487/RFC5023, October 2007, <https://www.rfc-editor.org/info/rfc5023>. [RFC7632] Waltermire, D. and D. Harrington, "Endpoint Security Posture Assessment: Enterprise Use Cases", RFC 7632, DOI 10.17487/RFC7632, September 2015, <https://www.rfc-editor.org/info/rfc7632>. [RFC8248] Cam-Winget, N. and L. Lorenzin, "Security Automationall registered components, - The Orchestrator MUST have the capability to inventory andContinuous Monitoring (SACM) Requirements", RFC 8248, DOI 10.17487/RFC8248, September 2017, <https://www.rfc-editor.org/info/rfc8248>. [RFC8322] Field, J., Banghart, S.,manage its "roster" (the list of registered components), - The Orchestrator MUST support making directed requests to registered components over the component's administrative interface, as configured by the "/orchestrator/[component-unique-identifier]" topic. Administrative interface functions are described by their taxonomy, below. 4.2.2. Component Onboarding Component onboarding describes how an individual component becomes part of the ecosystem; registering with the orchestrator, advertising capabilities, establishing its administrative interface, andD. Waltermire, "Resource- Oriented Lightweight Information Exchange (ROLIE)", RFC 8322, DOI 10.17487/RFC8322, February 2018, <https://www.rfc-editor.org/info/rfc8322>. [XMPPEXT] "XMPP Extensions", n.d., <https://xmpp.org/extensions/>. Appendix A. Mappingsubscribing toRFC8248 TODO: Consider removing or placing in a separate solution draft.relevant topics. The component onboarding workflow involves multiple steps: - The component first authenticates to the Integration Service - The component then initiates registration with the Orchestrator, per the Section 5.2 Once the component has onboarded and registered with the Orchestrator, its administrative interface will have been established via the "/orchestrator/[component-unique-identifier]" topic. Thissection provides a mapping of XMPPadministrative interface allows the component to advertise its capabilities to the Orchestrator andXMPP Extensionsin return, allow the Orchestrator to direct capability-specific topic registration to therelevant requirements from [RFC8248]. Incomponent. This is performed using thetableSection 5.3.1 taxonomy. Further described below, theID and Name columns provide"capability advertisement handshake" first assumes theID and Name ofonboarding component has therequirement directly out of [RFC8248]. The Supported By column may contain one of several values: o N/A: The requirement is not applicableability tothis architectural exploration o Architecture: This architecture (possibly assuming some components) should meet the requirement o XMPP: The set of XMPP Core specifications and the collection of applicable extensions, deployment, and operational considerations. o XMPP-Core: The requirement is satisfieddescribe its capabilities so they may be understood bya core XMPP feature o XEP-nnnn:the Orchestrator (TBD on capability advertisement methodology). * Therequirement is satisfied bycomponent sends anumbered XMPP extension (see [XMPPEXT]) o Operational: The requirement is an operational concern or can be addressed by anmessage with its operationaldeployment o Implementation:capabilities over the administrative interface: "/orchestrator/[component- unique-identifier]" * Therequirement is an implementation concern If there is no entry inOrchestrator receives theSupported By column, then there is a gap that must be filled. +----------+----------------------------------------+---------------+ | ID | Name | Supported By | +----------+----------------------------------------+---------------+ | G-001 | Solution Extensibility | XMPP-Core | | | | | | G-002 | Interoperability | XMPP | | | | | | G-003 | Scalability | XMPP | | | | | | G-004 | Versatility | XMPP-Core | | | | | | G-005 | Information Extensibility | XMPP-Core | | | | | | G-006 | Data Protection | Operational | | | | | | G-007 | Data Partitioning | Operational | | | | | | G-008 | Versioning and Backward Compatibility | XEP-0115/0030 | | | | | | G-009 | Information Discovery | XEP-0030 | | | | | | G-010 | Target Endpoint Discovery | XMPP-Core | | | | | | G-011 | Push and Pull Access | XEP-0060/0312 | | | | | | G-012 | SACM Component Interface | N/A | | | | | | G-013 | Endpoint Locationcomponent's capabilities, persists them, andNetwork Topology | | | | | | | G-014 | Target Endpoint Identity | XMPP-Core | | | | | | G-015 | Data Access Control | | | | | | | ARCH-001 |responds with the list of topics to which the component should subscribe, in order to receive notifications, instructions, or other directives intended to invoke the component's supported capabilities. * The component subscribes to the topics provided by the Orchestrator 4.3. ComponentFunctions | XMPP | | | | | | ARCH-002 | Scalability | XMPP-Core | | | | | | ARCH-003 | Flexibility | XMPP-Core | | | | | | ARCH-004 | SeparationInteractions Component interactions describe functionality between components relating to collection, evaluation, or other downstream processes. 4.3.1. Initiate Ad-Hoc Collection The Orchestrator supplies a payload ofDatacollection instructions to a topic or set of topics to which Posture Collection Services are subscribed. The receiving PCS components perform the required collection based on their capabilities. The PCS then forms a payload of collected posture attributes (including endpoint identifying information) andManagement | | | | Functions | | | | | | | ARCH-005 | Topology Flexibility | XMPP-Core | | | | | | ARCH-006 | Capability Negotiation | XEP-0115/0030 | | | | | | ARCH-007 | Role-Based Authorization | XMPP-Core | | | | | | ARCH-008 | Context-Based Authorization | | | | | | | ARCH-009 | Time Synchronization | Operational | | | | | | IM-001 | Extensiblepublishes that payload to the topic(s) to which the Posture Attribute Repository is subscribed, for persistence. 4.3.2. Coordinate Periodic Collection Similar to ad-hoc collection, the Orchestrator supplies a payload of collection instructions containing additional information regarding collection periodicity, to the topic or topics to which Posture Collection Services are subscribed. 4.3.2.1. Schedule Periodic Collection Collection instructions include information regarding the schedule for collection, for example, every day at Noon, or every hour at 32 minutes past the hour. 4.3.2.2. Cancel Periodic Collection The Orchestrator supplies a payload of instructions to a topic or set of topics to which Posture Collection Services are subscribed. The receiving PCS components cancel the identified periodic collection executing on that PCS. 4.3.3. Coordinate Observational/Event-based Collection In these scenarios, the "observer" acts as the Posture Collection Service. Interactions with the observer could specify a time period of observation and potentially information intended to filter observed posture attributes to aid the PCS in determining those attributes that are applicable for collection and persistence to the Posture AttributeVocabulary | N/A | | | | | | IM-002 |Repository. 4.3.3.1. Initiate Observational/Event-based Collection The Orchestrator supplies a payload of instructions to a topic or set of topics to which PostureData Publication | N/A | | | | | | IM-003 | Data Model Negotiation | N/A | | | | | | IM-004 | Data Model Identification | N/A | | | | | | IM-005 | Data Lifetime Management | N/A | | | | | | IM-006 | SingularityCollection Services (observers) are subscribed. This payload could include specific instructions based on the observer's capabilities to determine specific posture attributes to observe andModularity | N/A | | | | | | DM-001 | Element Association | N/A | | | | | | DM-002 | Data Model Structure | N/A | | | | | | DM-003 | Search Flexibility | N/A | | | | | | DM-004 | Full vs. Partial Updates | N/A | | | | | | DM-005 | Loose Coupling | N/A | | | | | | DM-006 | Data Cardinality | N/A | | | | | | DM-007 | Data Model Negotiation | N/A | | | | | | DM-008 | Data Origin | N/A | | | | | | DM-009 | Origination Time | N/A | | | | | | DM-010 | Data Generation | N/A | | | | | | DM-011 | Data Source | N/A | | | | | | DM-012 | Data Updates |collect. 4.3.3.2. Cancel Observational/Event-based Collection The Orchestrator supplies a payload of instructions to a topic or set of topics to which Posture Collection Services are subscribed. The receiving PCS components cancel the identified observational/event- based collection executing on that PCS. 4.3.4. Persist Collected Posture Attributes [TBD] Normalization? 4.3.5. Initiate Ad-Hoc Evaluation [TBD] ### Coordinate Periodic Evaluation [TBD] #### Schedule [TBD] #### Cancel [TBD] ### Coordinate Change-based Evaluation [TBD] i.e. if a posture attribute in the repository is changed, trigger an evaluation of particular policy items 4.3.6. Queries [TBD] Queries should allow for a "freshness" time period, allowing the requesting entity to determine if/when posture attributes must be re-collected prior to performing evaluation. This freshness time period can be "zeroed out" for the purpose of automatically triggering re-collection regardless of the most recent collection. 5. Taxonomy 5.1. Orchestrator Registration The Orchestrator Registration taxonomy describes how an Orchestrator onboards to the ecosystem, or how it returns from a non-operational state. 5.1.1. Topic N/A| | | | | | DM-013 | Multiple Collectors |5.1.2. Interaction Type Directed (Request/Response) 5.1.3. Initiator Orchestrator 5.1.4. Request Payload N/A| | | | | | DM-014 | Attribute Extensibility |5.1.5. Receiver N/A| | | | | | DM-015 | Solicited vs. Unsolicited Updates |5.1.6. Process Description Once the Orchestrator has authenticated to the Integration Service, it must establish (or re-establish) any service handlers interacting with administrative interfaces and/or general operational interfaces. For initial registration, the Orchestrator MUST enable capabilities to: * Receive onboarding requests via the "/orchestrator/registration" topic, * Generate, manage, and persist unique identifiers for all registered components, * Inventory and manage its "roster" (the list of registered components), and * Support making directed requests to registered components over the component's administrative interface, as configured by the "/orchestrator/[component-unique-identifier]" topic. Administrative interfaces are to be re-established through the inventory of previously registered components, such as Posture Collection Services, Repositories, or Posture Evaluation Services. 5.1.7. Response Payload N/A| | | | | | DM-016 | Transfer Agnostic |5.1.8. Response Processing N/A| | | | | | OP-001 | Time Synchronization | | | | | | | OP-002 | Collection Abstraction | | | | | | | OP-003 | Collection Composition | | | | | | | OP-004 | Attribute-Based Query | | | | | | | OP-005 | Information-Based Query5.2. Component Registration Component onboarding describes how an individual component becomes part of the ecosystem; registering withFiltering | | | | | | | OP-006 | Operation Scalability | | | | | | | OP-007 | Data Abstraction | | | | | | | OP-008 | Provider Restriction | | | | | | | T-001 | Multiple Transfer Protocol Support | Architecture | | | | | | T-002 | Data Integrity | Operational | | | | | | T-003 | Data Confidentiality | Operational | | | | | | T-004 | Transfer Protection | | | | | | | T-005 | Transfer Reliability | | | | | | | T-006 | Transfer-Layer Requirements | | | | | | | T-007 | Transfer Protocol Adoption | Architecture | +----------+----------------------------------------+---------------+ Appendix B. Example Components TODO: Consider removing. B.1. Policythe orchestrator, advertising capabilities, establishing its administrative interface, and subscribing to relevant topics. 5.2.1. Topic "/orchestrator/registration" "[component-type]" includes "pcs", "repository", "pes", and MORE TBD 5.2.2. Interaction Type Directed (Request/Response) 5.2.3. Initiator Any component wishing to join the ecosystem, such as Posture Collection Services, Repositories (policy, collection content, posture attribute, etc), Posture Evaluation ServicesConsiderand more. 5.2.4. Request Payload [TBD] Information Elements, such as - identifying-information - component-type (pcs, pes, repository, etc) - name - description 5.2.5. Receiver Orchestrator 5.2.6. Process Description When the Orchestrator receives the component's request for onboarding, it will: - Generate a unique identifier, "[component- unique-identifier]", for the onboarding component, - Persist required information (TBD probably need more specifics), including the "[component-unique-identifier]" to its component inventory, enabling an up-to-date roster of components being orchestrated, - Establish the administrative interface via the "/orchestrator/[component- unique-identifier]" topic. 5.2.7. Response Payload [TBD] Information Elements - component-unique-identifier 5.2.8. Response Processing Successful receipt of the Orchestrator's response, including the "[component-unique-identifier]" indicates the component is onboarded to the ecosystem. Using the response payload, the component can then establish its end of the administrative interface with the Orchestrator, using the "/orchestrator/[component-unique-identifier]" topic. Given this administrative interface, the component can then initiate the Section 5.3.1 5.3. Orchestrator-to-Component Administrative Interface A number of functions may take place which, instead of being published to a multi-subscriber topic, may require direct interaction between an Orchestrator and a registered component. During component onboarding, this direct channel is established first by the Orchestrator and subsequently complemented by the onboarding component. 5.3.1. Capability Advertisement Handshake Capability advertisement, otherwise known as service discovery, is necessary to establish and maintain a cooperative ecosystem of tools. Using this capability advertisement "handshake", the Orchestrator becomes knowledgeable of apolicy server conforming to [RFC8322]. [RFC8322] describescomponent's operational capabilities, the endpoints/services with which the component interacts, and establishes aRESTful way based ondirect mode of contact for invoking those capabilities. 5.3.1.1. Topic "/orchestrator/[component-unique-identifier]" 5.3.1.2. Interaction Type Directed (Request/Response) 5.3.1.3. Initiator Any ecosystem component (minus theATOM Publishing Protocol ([RFC5023])Orchestrator) 5.3.1.4. Request Payload [TBD] Information Elements - component-type - component-unique- identifier - interaction-type (capability-advertisement): - list of capabilities - list of endpoints/services 5.3.1.5. Receiver Orchestrator 5.3.1.6. Process Description Upon receipt of the component's capability advertisement, it SHOULD: - Persist the component's capabilities tofind specific data collections. While this represents a specific binding (i.e. RESTful APIthe Orchestrator's inventory - Coordinate, based on[RFC5023]),the supplied capabilities, a list of topics to which the component should subscribe 5.3.1.7. Response Payload [TBD] Information Elements - list of topics to subscribe 5.3.1.8. Response Processing Once the component has received the response to its capability advertisement, it should subscribe to the Orchestrator-provided topics. 5.3.2. Directed Collection ### Directed Evaluation ### Heartbeat 5.4. [Taxonomy Name] DESCRIPTION OF TAXONOMY 5.4.1. Topic "/name/of/topic" ### Interaction Type [Directed (Request/Response) -or- Publish/Subscribe] ### Initiator [Component sending/publishing the payload] ### Request Payload DESCRIPTION OF INFORMATION MODEL OF REQUEST PAYLOAD; i.e. what elements need to be in whatever format in the payload. ### Receiver [Component receiving/subscribed-to the payload] ### Process Description [What the receiver does with the payload] ### Response Payload DESCRIPTION OF INFORMATION MODEL OF RESPONSE PAYLOAD; i.e. what elements need to be in whatever format in the payload. ### Response Processing [What the initiator does with any response, if there is one] 6. Privacy Considerations [TBD] 7. Security Considerations [TBD] 8. IANA Considerations [TBD] Revamp this section after the configuration assessment workflow is fleshed out. IANA tables can probably be used to make life amore abstract waylittle easier. We would like a place tolook at ROLIE. ROLIE provides notional workspacesenumerate: * Capability/operation semantics * SACM Component implementation identifiers * SACM Component versions * Associations of SACM Components (and versions) to specific Capabilities * Collection sub-architecture Identification 9. References 9.1. Normative References [I-D.ietf-sacm-ecp] Haynes, D., Fitzgerald-McKay, J., and L. Lorenzin, "Endpoint Posture Collection Profile", draft-ietf-sacm- ecp-05 (work in progress), 21 June 2019, <http://www.ietf.org/internet-drafts/draft-ietf-sacm-ecp- 05.txt>. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc-editor.org/info/rfc2119>. [RFC8412] Schmidt, C., Haynes, D., Coffin, C., Waltermire, D., andcollections,J. Fitzgerald-McKay, "Software Inventory Message andprovides the concept of information categoriesAttributes (SWIMA) for PA-TNC", RFC 8412, DOI 10.17487/RFC8412, July 2018, <https://www.rfc-editor.org/info/rfc8412>. [RFC8600] Cam-Winget, N., Ed., Appala, S., Pope, S., andlinks. Strictly speaking, these are logical concepts independent of the RESTful binding ROLIE specifies. In other words, ROLIE binds a logical interface (i.e. GET workspace, GET collection, SET entry,P. Saint- Andre, "Using Extensible Messaging andso on) to a specific mechanism (namely an ATOM PublicationPresence Protocolextension). It is not inconceivable to believe there could be a different interface mechanism, or a connector, providing these same operations using XMPP-Grid as the transfer mechanism. Even if a [RFC8322] server were external to an organization, there would be a need(XMPP) fora policy source inside the organization as well,Security Information Exchange", RFC 8600, DOI 10.17487/RFC8600, June 2019, <https://www.rfc-editor.org/info/rfc8600>. 9.2. Informative References [CISCONTROLS] "CIS Controls v7.0", May 2020, <https://www.cisecurity.org/controls>. [draft-birkholz-sacm-yang-content] Birkholz, H. andit may be preferred for such a policy source to be connected directly to the ecosystem's communication infrastructure. B.2. Software InventoryN. Cam-Winget, "YANG subscribed notifications via SACM Statements", May 2020, <https://tools.ietf.org/html/draft-birkholz-sacm-yang- content-01>. [HACK100] "IETF 100 Hackathon - Vulnerability Scenario EPCP+XMPP", May 2020, <https://www.github.com/sacmwg/vulnerability-scenario/ ietf-hackathon>. [HACK101] "IETF 101 Hackathon - Configuration Assessment XMPP", May 2020, <https://www.github.com/CISecurity/Integration>. [HACK102] "IETF 102 Hackathon - YANG Collection on Traditional Endpoints", May 2020, <https://www.github.com/CISecurity/YANG>. [HACK103] "IETF 103 Hackathon - N/A", May 2020, <https://www.ietf.org/how/meetings/103/>. [HACK104] "IETF 104 Hackathon - A simple XMPP client", May 2020, <https://github.com/CISecurity/SACM-Architecture>. [HACK105] "IETF 105 Hackathon - A more robust XMPP client including collection extensions", May 2020, <https://github.com/CISecurity/SACM-Architecture>. [HACK99] "IETF 99 Hackathon - Vulnerability Scenario EPCP", May 2020, <https://www.github.com/sacmwg/vulnerability-scenario/ ietf-hackathon>. [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-16 (work in progress), 14 December 2018, <http://www.ietf.org/internet-drafts/draft-ietf-sacm- terminology-16.txt>. [NIST800126] Waltermire, D., Quinn, S., Booth, H., Scarfone, K., and D. Prisaca, "SP 800-126 Rev. 3 - TheSACM working group has accepted work onTechnical Specification for theEndpoint Posture Collection Profile [I-D.ietf-sacm-ecp], which describes a collection architectureSecurity Content Automation Protocol (SCAP) - SCAP Version 1.3", February 2018, <https://csrc.nist.gov/publications/detail/sp/800-126/rev- 3/final>. [NISTIR7694] Halbardier, A., Waltermire, D., andmay be viewed as a collector coupled with a collection-specific repository. Posture Manager Endpoint Orchestrator +---------------+ +---------------+ +--------+ | | | | | | | +-----------+ | | +-----------+ | | |<---->| | Posture | | | | Posture | | | | pub/ | | Validator | | | | Collector | | | | sub | +-----------+ | | +-----------+ | +--------+ | | | | | | | | | | | | Evaluator Repository | | | | | | +------+ +--------+ | +-----------+ |<-------| +-----------+ | | | | | | | Posture | | report | |M. Johnson, "NISTIR 7694 Specification for Asset Reporting Format 1.1", May 2020, <https://csrc.nist.gov/publications/detail/nistir/7694/ final>. [RFC5023] Gregorio, J., Ed. and B. de hOra, Ed., "The Atom Publishing Protocol", RFC 5023, DOI 10.17487/RFC5023, October 2007, <https://www.rfc-editor.org/info/rfc5023>. [RFC7632] Waltermire, D. and D. Harrington, "Endpoint Security Posture| | | | | | | | Collection| | | | Collection| | | |<-----> | |<-----| | Manager | | query | | Engine | | | |request/| | store| +-----------+ |------->| +-----------+ | | |respond | | | | | | | | | | | | | | +------+ +--------+ +---------------+ +---------------+ Figure 6: EPCP Collection Architecture In Figure 6, anyAssessment: Enterprise Use Cases", RFC 7632, DOI 10.17487/RFC7632, September 2015, <https://www.rfc-editor.org/info/rfc7632>. [RFC8248] Cam-Winget, N. and L. Lorenzin, "Security Automation and Continuous Monitoring (SACM) Requirements", RFC 8248, DOI 10.17487/RFC8248, September 2017, <https://www.rfc-editor.org/info/rfc8248>. [RFC8322] Field, J., Banghart, S., and D. Waltermire, "Resource- Oriented Lightweight Information Exchange (ROLIE)", RFC 8322, DOI 10.17487/RFC8322, February 2018, <https://www.rfc-editor.org/info/rfc8322>. [XMPPEXT] "XMPP Extensions", May 2020, <https://xmpp.org/extensions/>. Appendix A. Security Domain Workflows This section describes three primary information security domains from which workflows may be derived: IT Asset Management, Vulnerability Management, and Configuration Management. A.1. IT Asset Management Information Technology asset management is easier said than done. The [CISCONTROLS] have two controls dealing with IT asset management. Control 1, Inventory and Control ofthe communications between the Posture ManagerHardware Assets, states, "Actively manage (inventory, track, andEPCP components to its left could be performed directly or indirectly using a given message transfer mechanism. For example,correct) all hardware devices on thepub/sub interface betweennetwork so that only authorized devices are given access, and unauthorized and unmanaged devices are found and prevented from gaining access." Control 2, Inventory and Control of Software Assets, states, "Actively manage (inventory, track, and correct) all software on theOrchestratornetwork so that only authorized software is installed and can execute, and that unauthorized and unmanaged software is found and prevented from installation or execution." In spirit, this covers all of thePosture Manager could be using a proprietary methodprocessing entities on your network (as opposed to things like network cables, dongles, adapters, etc.), whether physical orusing [RFC8600]virtual, on-premises orsome other pub/sub mechanism. Similarly, the store connection fromin thePosture Managercloud. A.1.1. Components, Capabilities and Workflow(s) TBD A.1.1.1. Components TBD A.1.1.2. Capabilities An IT asset management capability needs tothe Repository couldbeperformed internally to a given implementation, via a RESTful API invocation over HTTPS, or even overable to: * Identify and catalog new assets by executing Target Endpoint Discovery Tasks * Provide information about its managed assets, including uniquely identifying information (for that enterprise) * Handle software and/or hardware (including virtual assets) * Represent cloud hybrid environments A.1.1.3. Workflow(s) TBD A.2. Vulnerability Management Vulnerability management is apub/sub mechanism. Our assertionrelatively established process. To paraphrase the [CISCONTROLS], continuous vulnerability management isthattheEvaluator, Repository, Orchestrator,act of continuously acquiring, assessing, andPosture Manager all have the potential to represent SACM Components with specific capability interfaces that can be logically specified, then boundtaking subsequent action on new information in order toone or more specific transfer mechanisms (i.e. RESTful API, [RFC8322], [RFC8600],identify andso on). B.3. Datastream Collection [NIST800126], also known as SCAP 1.3, providesremediate vulnerabilities, therefore minimizing thetechnical specificationswindow of opportunity fora "datastream collection". The specification describesattackers. A vulnerability assessment (i.e. vulnerability detection) is performed in two steps: * Endpoint information collected by the endpoint management capabilities is examined by the vulnerability management capabilities through Evaluation Tasks. * If the"datastream collection" as being "composed of SCAPdatastreams and SCAP source components". A "datastream" provides an encapsulation ofpossessed by theSCAP source components required to, for example, perform configuration assessment onendpoint management capabilities is insufficient, agiven endpoint. These source components include XCCDF checklists, OVAL Definitions, and CPE Dictionary information. A single "datastream collection" may encapsulate multiple "datastreams",Collection Task is triggered andreference any number of SCAP components. Datastream collections were intended to provide an envelope enabling transfer of SCAP data more easily. The [NIST800126] specification also definesthe"SCAP resultnecessary datastream" as being conformant to the Asset Reporting Format specification, defined in [NISTIR7694]. The Asset Reporting Format provides an encapsulation of the SCAP source components, Asset Information, and SCAP result components, such as system characteristics and state evaluation results. What [NIST800126]did not doisspecifycollected from theinterface for finding or acquiring source datastream information, nor an interface for publishing result information. Discoveringtarget endpoint. Vulnerability detection relies on theactual resources for thisexamination of different endpoint informationcould be done via ROLIE, as described independing on thePolicy Services section above, but other repositoriesnature ofSCAP data exist as well. B.4. Network Configuration Collection [draft-birkholz-sacm-yang-content] illustratesaSACM Component incorporatingspecific vulnerability. Common endpoint information used to detect aYANG Push client function andvulnerability includes: * A specific software version is installed on the endpoint * File system attributes * Specific state attributes In some cases, the endpoint information needed to determine anXMPP-grid publisher function. [draft-birkholz-sacm-yang-content] further states "the output ofendpoint's vulnerability status will have been previously collected by theYANG Push client function is encapsulatedendpoint management capabilities and available in aSACM Content Element envelope, which is again encapsulatedRepository. However, ina SACM statement envelope" which are published, essentially, via an XMPP- Grid Connector for SACM Components also part ofother cases, theXMPP-Grid. This isnecessary endpoint information will not be readily available in aspecific example of an existingRepository and a Collection Task will be triggered to perform collectionmechanism being adaptedfrom the target endpoint. Of course, some implementations of endpoint management capabilities may prefer to enable operators to perform this collection even when sufficient information can be provided by theXMPP-Grid message transfer system. Appendix C. Exploring An XMPP-based Solution TODO: Consider removing or placing in a separate draft. Ongoing work has been taking place aroundendpoint management capabilities (e.g. there may be freshness requirements for information). A.2.1. Components, Capabilities andduring IETF hackathons.Workflow(s) TBD A.2.1.1. Components TBD A.2.1.2. Capabilities TBD A.2.1.3. Workflow(s) TBD A.3. Configuration Management Configuration management involves configuration assessment, which requires state assessment. Thelist of hackathon efforts follows: o [HACK99]: A partial implementation of a vulnerability assessment scenario involving[CISCONTROLS] specify two high-level controls concerning configuration management (Control 5 for non- network devices and Control 11 for network devices). As an[I-D.ietf-sacm-ecp] implementation, a [RFC8322] implementation,aside, these controls are listed separately because many enterprises have different organizations for managing network infrastructure anda proprietary evaluator to pullworkload endpoints. Merging the two controls results in thepieces together. o [HACK100]: Work to combinefollowing paraphrasing: Establish, implement, and actively manage (track, report on, correct) thevulnerability assessment scenario from [HACK99] with an XMPP-based YANG push model. o [HACK101]: A fully automatedsecurity configurationassessment implementationof systems usingXMPP (specifically Publish/Subscribe capabilities) asacommunication mechanism. o [HACK102]: An exploration of how we might model assessment, collection,rigorous configuration management andevaluation abstractly,change control process in order to prevent attackers from exploiting vulnerable services andthen rely on YANG expressions for the attributes of traditional endpoints. o [HACK103]: No SACM participation at the Bangkok hackathon. o [HACK104]: Basic XMPP-to-Concise MAP - Createdsettings. Typically, anXMPP adapter that can accept basic posture attributesenterprise will use configuration guidance from a reputable source, andtranslate themfrom time toConcise MAP. This hackathon only provedtime they may tailor theconceptguidance from thatsystem characteristics information can be transported via XMPP and translatedsource prior toa (very basic) concise MAP implementation. o [HACK105]: Advanced XMPP-to-Concise MAP: Full orchestrationadopting it as part ofcollection capabilities using XMPP. Collector implementations extend the core XMPP structure to allow OVAL collection instructions (OVAL objects) to inform posture attribute collection. Collected system characteristics can betheir enterprise standard. The enterprise standard is then provided to theConcise MAP XMPP adapter using all 3 available XMPP capabilities: Publish/Subscribe, Information Query (iq - request/ response) stanzas,appropriate configuration assessment tools and they assess endpoints and/or appropriate endpoint information. A preferred flow follows: * Reputable source publishes new ordirect Message stanzas. CDDL was created to map collected posture attributesupdated configuration guidance * Enterprise configuration assessment capability retrieves configuration guidance from reputable source * Optional: Configuration guidance is tailored for enterprise- specific needs * Configuration assessment tool queries asset inventory repository toConcise MAP structure. The XMPP adapter translates the incoming system characteristics and stores the information in the MAP. Figure 7 depicts a slightly more detailed view of the architecture (within the enterprise boundary) - one that fosters the development ofretrieve apluggable ecosystemlist ofcooperative tools. Existing collection mechanisms can be brought into thisaffected endpoints * Configuration assessment tool queries configuration state repository to evaluate compliance * If information is stale or unavailable, configuration assessment tool triggers an ad hoc assessment The SACM architectureby specifyingneeds to support varying deployment models to accommodate theinterfacecurrent state of thecollectorindustry, but should strongly encourage event-driven approaches to monitoring configuration. A.3.1. Components, Capabilities andcreating the XMPP-Grid Connector binding for that interface. Additionally, while not directly depicted in Figure 7, this architecture does allow point-to-point interfaces. In fact, [RFC8600]Workflow(s) This section providesbrokeringmore detail about the components and capabilitiesto facilitate such point- to-point data transfers). Additionally, each ofrequired when considering theSACMaforementioned configuration management workflow. A.3.1.1. Componentsdepicted in Figure 7 may be a provider, a consumer, or both, depending on the workflow in context. +--------------+ +--------------+ | Orchestrator | | Repositories | +------^-------+ +------^-------+ | | | | +-------v--------------------------v--------+ +-----------------+ | XMPP-Grid+ <-----> Downstream Uses | +------------------------^------------------+ +-----------------+ | | +-------v------+ | XMPP-Grid | | Connector(s) | +------^-------+ | +------v-------+ | Collector(s) | +--------------+ Figure 7: XMPP-based Architecture [RFC8600] detailsThe following is anumberminimal list ofXMPP extensions (XEPs) that MUST be utilizedSACM Components required tomeetimplement theneedsaforementioned configuration assessment workflow. * Configuration Policy Feed: An external source of authoritative configuration recommendations. * Configuration Policy Repository: An internal repository of enterprise standard configurations. * Configuration Assessment Orchestrator: A component responsible for orchestrating assessments. * Posture Attribute Collection Subsystem: A component responsible for collection of posture attributes from systems. * Posture Attribute Repository: A component used for storing system posture attribute values. * Configuration Assessment Evaluator: A component responsible for evaluating system posture attribute values against expected posture attribute values. * Configuration Assessment Results Repository: A component used for storing evaluation results. A.3.1.2. Capabilities Per [RFC8248], solutions MUST support capability negotiation. Components implementing specific interfaces and operations (i.e. interactions) will need a method of[RFC7632] and [RFC8248]: o Service Discovery (XEP-0030): Service Discovery allows XMPP entitiesdescribing their capabilities todiscover information aboutotherXMPP entities. Two kinds of informationcomponents participating in the ecosystem; for example, "As a component in the ecosystem, I canbe discovered:assess theidentity and capabilitiesconfiguration ofan entity, such as supported features, and items associated with an entity. o Publish-Subscribe (XEP-0060): The PubSub extension enables entities to create nodes (topics) at a PubSub serviceWindows, MacOS, andpublish information at those nodes. Once published, an event notification is broadcast to all entities that have subscribed to that node. At this point, [RFC8600] specifies fewer features than SACM requires,AWS using OVAL". A.3.1.3. Configuration Assessment Workflow This section describes the components andthereinteractions in a basic configuration assessment workflow. For simplicity, error conditions areother XMPP extensions (XEPs) we need to consider to meet the needs of [RFC7632]recognized as being necessary and[RFC8248]. In Figure 7 we therefore use "XMPP-Grid+" to indicate something more than [RFC8600] alone, even though weare notyet fully confident in the exact set of XMPP- related extensions we will require. The authors propose work to extend (or modify) [RFC8600] to include additional XEPs - possibly the following: o Entity Capabilities (XEP-0115): This extension definesdepicted. When one component messages another component, themethods for broadcasting and dynamically discovering an entities' capabilities. This informationmessage istransported via standard XMPP presence. Example capabilities that could be discovered could include support for posture attribute collection, support for specific types of posture attribute collection such as EPCP, SWIMA, OVAL, or YANG. Other capabilities are stillexpected to bedetermined. o Ad Hoc Commands (XEP-0050): This extension allowshandled appropriately unless there is anXMPP entity to advertise and execute application-specific commands. Typically the commands contain data forms (XEP-0004)error condition, or other notification, messaged inorder to structure the information exchange. This extension may be usable for simple orchestration (i.e. "do assessment"). o HTTP File Upload (XEP-0363): The HTTP File Upload extension allows for large data sets to be published to a specific path on an HTTP server,return. +-------------+ +----------------+ +------------------+ +------------+ | Policy Feed | | Orchestrator | | Evaluation | | Evaluation | +------+------+ +-------+--------+ | Sub-Architecture | | Results | | | +---^----------+---+ | Repository | | | | | +------^-----+ | | | | | 1.| 3.| 8.| 9.| 10.| | | | | | | | | | | +------v-----------------v---------------+----------v-------------+-----+ | Integration Service | +-----+----------------------------------+----------^---------+------^--+ | | | | | | | | | | 2.| 4.| 5.| 6.| 7.| | | | | | | | | | | +-----v------+ +---v----------+---+ +--v------+--+ | Policy | | Collection | | Posture | | Repository | | Sub-Architecture | | Attribute | +------------+ +------------------+ | Repository | +------------+ Figure 5: Configuration Assessment Component Interactions Figure 5 depicts configuration assessment components andreceive a URL fromtheir interactions, whichthat file can later be downloaded again. XMPP messages and IQsaremeant to be compact, and large data sets, such as collected posture attributes, may exceedfurther described below. 1. A policy feed provides amessage size threshold. Usage of this XEP allows those larger data setsconfiguration assessment policy payload tobe persisted, thus necessitating onlythedownload URL to be passed via XMPP messages. o Personal Eventing Protocol (XEP-0163):Integration Service. 2. ThePersonal Eventing Protocol can be thought of asPolicy Repository, avirtual PubSub service, allowing an XMPP account to publish events only to their roster insteadconsumer ofa generic PubSub topic. This XEP may be useful inPolicy Feed information, receives and persists thecases when collection requestsPolicy Feed's payload. 3. Orchestration component(s), either manually invoked, scheduled, orqueries are only intended for a subset of endpoints and not an entire subscriber set. o File Repository and Sharing (XEP-0214): This extension definesevent-based, publish amethod for XMPP entitiespayload todesignate a set of file available for retrieval by other users of their choosing, and is based on PubSub Collections. o Easy User Onboarding (XEP-401): The goal of this extension is simplified client registration, andbegin the configuration assessment process. 4. If necessary, Collection Sub-Architecture components may beuseful when adding new endpoints or SACM componentsinvoked to collect neeeded posture attribute information. 5. If necessary, theecosystem. o Bidirectional-streams Over Synchronous HTTP (BOSH) (XEP-0124): BOSH emulatesCollection Sub-Architecture will provide collected posture attributes to thesemantics of a long-lived, bidirectional TCP connection between two entities (aka "long polling"). Consider a SACM component that is updated dynamically, i.e. an internal vulnerability definition repository ingesting data from a Feed/Integration Service for persistence to the Posture Attribute Repository. 6. The Posture Attribute Repositoryof External Data, andwill consume asecond SACM component such as an Orchestrator. Using BOSH,payload querying for relevant posture attribute information. 7. The Posture Attribute Repository will provide theOrchestrator can effectively continuously pollrequested information to thevulnerability definition repository for changes/updates. o PubSub Collection Nodes (XEP-0248): Effectively an extensionIntegration Service, allowing further orchestration payloads requesting the Evaluation Sub- Architecture perform evaluation tasks. 8. The Evaluation Sub-Architecture consumes the evaluation payload and performs component-specific state comparison operations toXEP-0060 (Publish-Subscribe), PubSub Collections aimproduce evaluation results. 9. A payload containing evaluation results are provided by the Evaluation Sub-Architecture tosimplify an entities' subscriptionthe Integration Service 10. Evaluation results are consumed by/persisted tomultiple related topics, and establishes a "node graph" relating parent nodesthe Evaluation Results Repository In the above flow, the payload information is expected toits descendents. An example "node graph" could be rooted in a "vulnerability definitions" topic, and contain descendent topics for OS family-level vulnerability definitions (i.e. Windows), and furtherconvey the context required by the receiving component forOS family version-level definitions (i.e. Windows 10 or Windows Server 2016). o PubSub Since (XEP-0312): This extension enablesthe action being taken under different circumstances. For example, asubscriberdirected message sent from an Orchestrator toautomatically receive PubSub and Personal Eventing Protocol (PEP) notifications since its last logout time. This extension maya Collection sub-architecture might beuseful in intermittent connection scenarios, or when entities disconnect and reconnecttelling that Collector tothe ecosystem. o PubSub Chaining (XEP-0253): This extension describes the federation of publishing nodes, enablingwatch apublish node of one serverspecific posture attribute and report only specific detected changes to the Posture Attribute Repository, or it might bea subscribertelling the Collector toa publishing nodegather that posture attribute immediately. Such details are expected to be handled as part ofanother server. C.1. Example Architecture using XMPP-Grid and Endpoint Posture Collection Protocol Figure 8 depicts a further detailed viewthat payload, not as part of the architectureincluding the Endpoint Posture Collection Protocol as the collection subsystem, illustrating the idea of a pluggable ecosystem of cooperative tools. +--------------------+ | Feeds/Repositories | | of External Data | +--------------------+ | ********************v*********************** Boundary of Responsibility ******* * | * * +--------------+ | +-------------------+ +-------------+ * * | Orchestrator | | | Posture Attr Repo | | Policy Repo | * * +------^-------+ | +---------^---------+ +---^---------+ * * | | | | +----------------+ * * | | | | | Downstream Uses| * * | | | | | +-----------+ | * * +------v---------v-----------v---------------v--+ | |Evaluations| | * * | XMPP-Grid <-------> +-----------+ | * * +----------------^-------------------^----------+ | +-----------+ | * * | | | | Analytics | | * * | | | +-----------+ | * * | +-----v--------+ | +-----------+ | * * | | Results Repo | | | Reporting | | * * | +--------------+ | +-----------+ | * * | +----------------+ * * +---------v-----------+ * * | XMPP-Grid Connector | * * +---------^-----------+ * * | * * +-----------------v-------------------------------------------------------+ * * | | * * | +--Posture Collection Manager------------------------------------------+| * * | |+-----------------------+ +----------------+ +----------------------+ || * * | || Communications Server | | Posture Server | | Posture Validator(s) | || * * | |+----------^------------+ +----------------+ +----------------------+ || * * | +-----------|----------------------------------------------------------+| * * | | | * * | +-----------|-------------------------Endpoint or Endpoint Proxy-------+| * * | |+----------v------------+ +----------------+ +----------------------+ || * * | || Communications Client | | Posture Client | | Posture Collector(s) | || * * | |+-----------------------+ +----------------+ +----------------------+ || * * | +----------------------------------------------------------------------+| * * +-----------------Endpoint Posture Collection Profile---------------------+ * * * ******************************************************************************* Figure 8: XMPP-based Architecture including EPCPdescribed herein. Authors' Addresses Adam W. Montville Center for Internet Security 31 Tech Valley Drive East Greenbush, NY 12061USAUnited States of America Email: adam.montville.sdo@gmail.com Bill Munyan Center for Internet Security 31 Tech Valley Drive East Greenbush, NY 12061USAUnited States of America Email: bill.munyan.ietf@gmail.com