--- 1/draft-ietf-sacm-arch-03.txt 2019-10-29 14:13:09.984489052 -0700 +++ 2/draft-ietf-sacm-arch-04.txt 2019-10-29 14:13:10.052490781 -0700 @@ -1,23 +1,23 @@ SACM Working Group A. Montville Internet-Draft B. Munyan Intended status: Standards Track CIS -Expires: March 9, 2020 September 06, 2019 +Expires: May 1, 2020 October 29, 2019 Security Automation and Continuous Monitoring (SACM) Architecture - draft-ietf-sacm-arch-03 + draft-ietf-sacm-arch-04 Abstract - This memo defines a Security Automation and Continuous Monitoring - (SACM) architecture. This work is built upon [RFC8600], and is + 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 @@ -28,21 +28,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on March 9, 2020. + This Internet-Draft will expire on May 1, 2020. Copyright Notice Copyright (c) 2019 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -51,62 +51,55 @@ 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 . . . . . . . . . . . . . . . . . . . 3 - 3.1. Architectural Components . . . . . . . . . . . . . . . . 4 - 3.1.1. Orchestrator . . . . . . . . . . . . . . . . . . . . 5 - 3.1.2. Repositories/CMDBs . . . . . . . . . . . . . . . . . 5 - 3.1.3. Component Integration Service . . . . . . . . . . . . 5 - 3.2. Sub-Architectures . . . . . . . . . . . . . . . . . . . . 6 + 3.1. SACM Role-based Architecture . . . . . . . . . . . . . . 4 + 3.2. Architectural Roles/Components . . . . . . . . . . . . . 5 + 3.2.1. Orchestrator(s) . . . . . . . . . . . . . . . . . . . 5 + 3.2.2. Repositories/CMDBs . . . . . . . . . . . . . . . . . 5 + 3.2.3. Integration Service . . . . . . . . . . . . . . . . . 5 3.3. Downstream Uses . . . . . . . . . . . . . . . . . . . . . 6 3.3.1. Reporting . . . . . . . . . . . . . . . . . . . . . . 6 - 3.3.2. Analytics . . . . . . . . . . . . . . . . . . . . . . 7 - 4. Sub-Architectural Components . . . . . . . . . . . . . . . . 7 - 4.1. Collection Sub-Architecture . . . . . . . . . . . . . . . 7 - 4.1.1. Posture Collection Service . . . . . . . . . . . . . 8 - 4.1.2. Endpoint . . . . . . . . . . . . . . . . . . . . . . 9 - 4.1.3. Posture Attribute Repository . . . . . . . . . . . . 9 - 4.2. Evaluation Sub-Architecture . . . . . . . . . . . . . . . 9 - 4.2.1. Posture Evaluation Service . . . . . . . . . . . . . 10 - 4.2.2. Policy Repository . . . . . . . . . . . . . . . . . . 10 - 4.2.3. Evaluation Results Repository . . . . . . . . . . . . 11 - 5. Interactions . . . . . . . . . . . . . . . . . . . . . . . . 11 - 6. Security Domain Workflows . . . . . . . . . . . . . . . . . . 12 - 6.1. IT Asset Management . . . . . . . . . . . . . . . . . . . 12 - 6.2. Vulnerability Management . . . . . . . . . . . . . . . . 13 - 6.3. Configuration Management . . . . . . . . . . . . . . . . 13 - 7. Configuration Management Components and Capabilities . . . . 14 - 7.1. Components . . . . . . . . . . . . . . . . . . . . . . . 15 - 7.2. Capabilities . . . . . . . . . . . . . . . . . . . . . . 15 - 8. Configuration Assessment Workflow . . . . . . . . . . . . . . 15 - 9. Privacy Considerations . . . . . . . . . . . . . . . . . . . 17 - 10. Security Considerations . . . . . . . . . . . . . . . . . . . 17 - 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 - 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 18 - 12.1. Normative References . . . . . . . . . . . . . . . . . . 18 - 12.2. Informative References . . . . . . . . . . . . . . . . . 18 - Appendix A. Mapping to RFC8248 . . . . . . . . . . . . . . . . . 20 - Appendix B. Example Components . . . . . . . . . . . . . . . . . 23 - B.1. Policy Services . . . . . . . . . . . . . . . . . . . . . 23 - B.2. Software Inventory . . . . . . . . . . . . . . . . . . . 24 - B.3. Datastream Collection . . . . . . . . . . . . . . . . . . 25 - B.4. Network Configuration Collection . . . . . . . . . . . . 25 - Appendix C. Exploring An XMPP-based Solution . . . . . . . . . . 25 + 3.3.2. Analytics . . . . . . . . . . . . . . . . . . . . . . 6 + 3.4. Sub-Architectures . . . . . . . . . . . . . . . . . . . . 7 + 3.4.1. Collection Sub-Architecture . . . . . . . . . . . . . 7 + 3.4.2. Evaluation Sub-Architecture . . . . . . . . . . . . . 9 + 4. Interactions . . . . . . . . . . . . . . . . . . . . . . . . 11 + 5. Security Domain Workflows . . . . . . . . . . . . . . . . . . 12 + 5.1. IT Asset Management . . . . . . . . . . . . . . . . . . . 12 + 5.1.1. Components, Capabilities and Workflow(s) . . . . . . 13 + 5.2. Vulnerability Management . . . . . . . . . . . . . . . . 13 + 5.2.1. Components, Capabilities and Workflow(s) . . . . . . 14 + 5.3. Configuration Management . . . . . . . . . . . . . . . . 15 + 5.3.1. Components, Capabilities and Workflow(s) . . . . . . 16 + 6. Privacy Considerations . . . . . . . . . . . . . . . . . . . 18 + 7. Security Considerations . . . . . . . . . . . . . . . . . . . 18 + 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 + 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 19 + 9.1. Normative References . . . . . . . . . . . . . . . . . . 19 + 9.2. Informative References . . . . . . . . . . . . . . . . . 19 + Appendix A. Mapping to RFC8248 . . . . . . . . . . . . . . . . . 21 + Appendix B. Example Components . . . . . . . . . . . . . . . . . 24 + B.1. Policy Services . . . . . . . . . . . . . . . . . . . . . 24 + B.2. Software Inventory . . . . . . . . . . . . . . . . . . . 25 + B.3. Datastream Collection . . . . . . . . . . . . . . . . . . 26 + B.4. Network Configuration Collection . . . . . . . . . . . . 26 + Appendix C. Exploring An XMPP-based Solution . . . . . . . . . . 27 C.1. Example Architecture using XMPP-Grid and Endpoint Posture - Collection Protocol . . . . . . . . . . . . . . . . . . . 29 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 31 + Collection Protocol . . . . . . . . . . . . . . . . . . . 30 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 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. @@ -125,408 +118,461 @@ 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 | +---------+----------+ - + -****************************************************** Enterprise Boundary *** - + - +--------------+ | +--------------------+ - | Orchestrator | | | Repositories/CMDBs | - +------^-------+ | +----------^---------+ + | +******************************************* Boundary of Responsibility ****** + | + +-----------------+ | +--------------------+ + | Orchestrator(s) | | | Repositories/CMDBs | + +---------^-------+ | +----------^---------+ | | | +--------------------+ | | | | Downstream Uses | | | | | +----------------+ | +-----------v----------v-------------v------+ | | Analytics | | - | Component Integration Service <------> +----------------+ | - +----- -----^--------------------------^----+ | +----------------+ | + | Integration Service <------> +----------------+ | + +-----------^--------------------------^----+ | +----------------+ | | | | | Reporting | | | | | +----------------+ | +-----------v-------------------+ | +--------------------+ | Collection Sub-Architecture | | +-------------------------------+ | - +---------------------v---------+ + +---------------v---------------+ | Evaluation Sub-Architecture | +-------------------------------+ - Figure 1: Notional Architecture + Figure 2: Notional Role-based Architecture - As shown in Figure 1, the SACM architecture consists of some basic - SACM Components communicating using a component integration service. - The component integration service is expected to maximally align with + 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 - component integration service will support brokered (i.e. point-to- - point) and proxied data exchange. + integration service will support brokered (i.e. point-to-point) and + proxied data exchange. - The enterprise boundary is not intended to imply a physical boundary. - Rather, the enterprise boundary is intended to be inclusive of - various cloud environments and vendor-provided services in addition - to any physical systems the enterprise operates. + 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. -3.1. Architectural Components +3.2. Architectural Roles/Components This document suggests a variety of players in a cooperative - ecosystem - we call these players 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. - Generally each role is either a consumer of information or a provider - of information. The Figure 1 diagram illustrates a number of SACM - components which are architecturally significant and therefore - warrant discussion and clarification. + 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. -3.1.1. Orchestrator +3.2.1. Orchestrator(s) - An Orchestration component exists to aid in the automation of + 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. -3.1.2. Repositories/CMDBs - - The Figure 1 diagram 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). - -3.1.3. Component Integration Service - - If each SACM component represents a set of services, capabilities, - and/or functions, the Component Integration Service represents the - "fabric" by which all those services, capabilities and functions are - woven together. The Component Integration Service acts as a message - broker, combining a canonical data model, a common command set, and a - messaging infrastructure to allow other SACM components to - communicate using a shared set of interfaces. The Component - Integration Service's brokering capabilities enable the exchange of - information, the orchestration of capabilities, message routing and - reliable delivery. The Component Integration Service minimizes the - dependencies from one system to another through the loose coupling of - applications through messaging. - - The Component 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 Component Integration Service to coordinate and - manage the sending and receiving of messages. The Component - 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. - - A number of pieces come together to form the Component Integration - Service: +3.2.2. Repositories/CMDBs - 1. Common communication infrastructure: The physical communications - infrastructure, providing a cross-platform, cross-language - universal adapter between SACM components. This infrastructure - commonly includes message routing capabilities to facilitate the - correct routing of messages from SACM component to SACM - component, as well as using Publish/Subscribe functionality to - facilitate sending messages to all receivers. + 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). - 2. Adapters: The use of a standard, canonical data model will likely - require SACM components to translate component-specific - information into the canonical format used by the message broker. +3.2.3. Integration Service - 3. Common command/interaction structure: Just as PC architectures - have a common set of commands to represent the different - operations possible on a physical bus, there must be common - interactions that all SACM components can understand. + 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. -3.2. Sub-Architectures + 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 Figure 1 shows two components representing the architectural - workflows involved in a cooperative ecosystem of SACM components: - Collection and Evaluation. The following section, Architectural - Workflows (TBD - ADD LINK) further expands on these components/ - workflows. + 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 1, a number of downstream uses exist in the + 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 - component integration services, using interactions described in this - draft. + integration services, using interactions described in this draft. 3.3.1. Reporting - The Reporting component represents the capabilities of the SACM - architecture dealing with the query and retrieval of collected + 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 the capabilities of the SACM - architecture dealing with the discovery, interpretation, and + 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. -4. Sub-Architectural Components +3.4. Sub-Architectures - This section describes the workflows derived from the interactions - with the two sub-architectures depicted in the Figure 1: Collection + Figure 2 shows two components representing sub-architectural roles + involved in a cooperative ecosystem of SACM components: Collection and Evaluation. -4.1. Collection Sub-Architecture +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 Component 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. + 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 | + | Orchestrator(s) | +-----------+----------------------------------------------+ | +------------------------------+ | | Posture Attribute Repository | | +--------------^---------------+ - | | - | | + Perform | + Collection | | Collected Data | ^ | | +-----------v------------------------------+---------------+ - | Component Integration Service | + | Integration Service | +----+------------------^-----------+------------------^---+ | | | | - | | | | v | v | Perform Collected Perform Collected Collection Data Collection Data | ^ | ^ | | | | - | | | | - +----v------------------+----+ +----v------------------+----+ - | Posture Collection Service | | Posture Collection Service | - +---^------------------------+ | | - | | | +------------------------+ | - | v | | Endpoint | | - Events Queries | +------------------------+ | - ^ | +----------------------------+ + +----v-----------------------+ +----v------------------+------+ + | Posture Collection Service | | Endpoint | + +---^------------------------+ | +--------------------------+ | + | | | |Posture Collection Service| | + | v | +--------------------------+ | + Events Queries +------------------------------+ + ^ | | | +---+-------------------v----+ | Endpoint | +----------------------------+ - Figure 2: Collection Sub-Architecture + Figure 3: Decomposed Collection Sub-Architecture -4.1.1. Posture Collection Service +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 Component Integration Service to receive collection + 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 Component 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 Component - Integration Service via similar channels. The various interaction - types are discussed later in this draft (TBD). + 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). -4.1.2. Endpoint +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. -4.1.3. Posture Attribute Repository +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. -4.2. Evaluation Sub-Architecture +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. -+---------------------------------------+ -| Orchestrator | -+-------------------+-------------------+ - | - | - | -+-------------------v-------------------+ -| Component Integration Service | -+--------+------------^--------^--------+ + +------------------+ + | Collection | +-------------------------------+ + | Sub-Architecture | | Evaluation Results Repository | ++--------------+ +--------^---------+ +-----------------^-------------+ +| Orchestrator | | | ++------+-------+ | | + | Perform Store Evaluation Results + Perform Collection | + Evaluation | | | | | ++------v----------------------v--------------------------------+-------------+ +| Integration Service | ++--------+----------------------------^----------------------^---------------+ | | | - v | Retrieve +--------------------------------+ - Perform | Posture <-------+ Posture Attribute Repository | - Evaluation | Attributes +--------------------------------+ - | | - | | - | | +--------------------------------+ - | +-----Retrieve <------+ Policy Repository | - | Policy +--------------------------------+ - | -+--------v------------------------------+ -| Posture Evaluation Service | -+----------------------------+----------+ - | - v - Evaluation - Results - | - | - +--------------------v----------+ - | Evaluation Results Repository | - +-------------------------------+ + | | | + Perform Retrieve Posture | + Evaluation Attributes Retrieve Policy + | | | + | | | ++--------v-------------------+ +-----v------+ +------v-----+ +| Posture Evaluation Service | | Posture | | Policy | ++----------------------------+ | Attribute | | Repository | + | Repository | +------------+ + +------------+ - Figure 3: Evaluation Sub-Architecture + Figure 4: Decomposed Evaluation Sub-Architecture -4.2.1. Posture Evaluation Service +3.4.2.1. Posture Evaluation Service - The Posture Evaluation Service represents the SACM component + 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. -4.2.2. Policy Repository +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 be Vulnerability Definition Data or configuration recommendations as part of a CIS Benchmark or DISA STIG. -4.2.3. Evaluation Results Repository +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 configuration attribute indicates a correct configuration of the endpoint, whereas meeting an expected state for a vulnerable software version indicates an incorrect and therefore vulnerable configuration. -5. Interactions +3.4.2.4. Posture Evaluation Workflow - SACM Components are intended to interact with other SACM Components. - These interactions can be thought of, at the level of this - architectural approach, as the combination of interfaces with their - supported operations. Each interaction will convey a payload of - information. The payload information is expected to contain sub- - domain-specific characteristics and instructions. + Posture evaluation is orchestrated through the Integration Service to + the appropriate Posture Evaluation Service. The PES will, through + coordination with the 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 use and + analysis. - o *Publish/Subscribe*: A component publishes information to a - messaging system and a set of other components, subscribed to that - information type, receive the published information. +4. Interactions - o *Request/Response*: A request/response interaction can take a - number of forms, but will always be synchronous operations - involving the requesting component waiting/blocking until a - response is received from the requested component or a timeout - occurs. + SACM Components are intended to interact with other SACM Components. + These interactions can be thought of, at the architectural level, as + the combination of interfaces with their supported operations. Each + interaction will convey a payload of information. The payload + information is expected to contain sub-domain-specific + characteristics and instructions. - * *Information Request*: An information request is simply one - component requesting information from another component, such - as an Orchestrator requesting collection capabilities from a - Posture Collection Service. + Two categories of interactions SHOULD be supported by the Integration + Service; broadcast interactions, and directed interactions. - * *Query*: A query interaction can take one of two forms, - "selection" or "storage". + o *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 Integration Service, + all subscribers to that topic are alerted and may consume the + message payload. A broadcast interaction may also simulate a + "directed" interaction when a topic only has a single subscriber. + An example of a broadcast interaction could be to publish to a + topic that new configuration assessment content is available. + Subscribing consumers receive the notification, and proceed to + collect endpoint configuration posture based on the new content. - + _Selection_: A component requests data from a repository. + o *Directed*: The intent of a directed interaction is to enable + point-to-point communications between a producer and consumer, + through the standard interfaces provided by the Integration + Service. The provider component indicates which consumer is + intended to receive the payload, and the Integration Service + routes the payload directly to that consumer. Two "styles" of + directed interaction exist, differing only by the response from + the payload consumer: - + _Storage_: A component provides data to be persisted in a - repository. + * *Synchronous (Request/Response)*: Synchronous, request/response + style interaction requires that the requesting component block + and wait for the receiving component to respond, or to time out + when that response is delayed past a given time threshold. A + synchronous interaction example may be querying a CMDB for + posture attribute information in order to perform an + evaluation. - o *Directive*: Commonly referred to as "Send-and-Forget", a - directive is an asynchronous interaction whereby a component - requests information from another component but does not wait/ - block for a response. The receiving component may reply later via - callbacks or further interactions, but it is not mandatory. + * *Asynchronous (Fire-and-Forget)*: An asynchronous interaction + involves the payload producer directing the message to a + consumer, but not blocking or waiting for a response. This + style of interaction allows the producer to continue on to + other activities without the need to wait for responses. This + style is particularly useful when the interaction payload + invokes a potentially 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. Each interaction will convey a payload of information. The payload - information is expected to contain sub-domain-specific - characteristics and instructions. + is expected to contain specific characteristics and instructions to + be interpreted by receiving components. -6. Security Domain Workflows +5. 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. -6.1. IT Asset Management +5.1. 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 of Hardware Assets, states, "Actively manage (inventory, track, and correct) all hardware devices on the network 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 the network 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 the processing entities on your network (as opposed to things like network cables, dongles, adapters, etc.), - whether physical or virtual. + whether physical or virtual, on-premises or in the cloud. + +5.1.1. Components, Capabilities and Workflow(s) + + TBD + +5.1.1.1. Components + + TBD + +5.1.1.2. Capabilities An IT asset management capability needs to be able to: o Identify and catalog 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 -6.2. Vulnerability Management +5.1.1.3. Workflow(s) + + TBD + +5.2. Vulnerability Management Vulnerability management is a relatively established process. To paraphrase the [CISCONTROLS], continuous vulnerability management is the act of continuously acquiring, assessing, and taking subsequent action on new information in order to identify and remediate vulnerabilities, therefore minimizing the window of opportunity for attackers. A vulnerability assessment (i.e. vulnerability detection) is performed in two steps: @@ -555,21 +601,37 @@ by the endpoint management capabilities and available in a Repository. However, in other cases, the necessary endpoint information will not be readily available in a Repository and a Collection Task will be triggered to perform collection from 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 the endpoint management capabilities (e.g. there may be freshness requirements for information). -6.3. Configuration Management +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 11 for network devices). As an aside, these controls are listed separately because many enterprises have different organizations for managing network infrastructure and workload endpoints. Merging the two controls results in the following paraphrasing: Establish, implement, and actively manage (track, report on, correct) the security configuration of systems @@ -600,27 +662,27 @@ o Configuration assessment tool queries configuration state repository to evaluate compliance o If information is stale or unavailable, configuration assessment tool triggers an ad hoc assessment The SACM architecture needs to support varying deployment models to accommodate the current state of the industry, but should strongly encourage event-driven approaches to monitoring configuration. -7. Configuration Management Components and Capabilities +5.3.1. Components, Capabilities and Workflow(s) This section provides more detail about the components and capabilities required when considering the aforementioned configuration management workflow. -7.1. Components +5.3.1.1. Components The following is a minimal list of SACM Components required to implement the aforementioned configuration assessment workflow. o Configuration Policy Feed: An external source of authoritative configuration recommendations. o Configuration Policy Repository: An internal repository of enterprise standard configurations. @@ -633,114 +695,121 @@ o Posture Attribute 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. -7.2. Capabilities +5.3.1.2. Capabilities Per [RFC8248], solutions MUST support capability negotiation. Components implementing specific interfaces and operations (i.e. interactions) will need a method of describing their capabilities to other components participating in the ecosystem; for example, "As a component in the ecosystem, I can assess the configuration of Windows, MacOS, and AWS using OVAL". -8. Configuration Assessment Workflow +5.3.1.3. Configuration Assessment Workflow This section describes the components and interactions in a basic configuration assessment workflow. For simplicity, error conditions are recognized as being necessary and are not depicted. When one component messages another component, the message is expected to be handled appropriately unless there is an error condition, or other notification, messaged in return. -+-------------+ -| Policy Feed | -+-----+-------+ - | 5.1 - 1 | +----------------------------------------+ - | | | -+-----v------+ 2 +----------------+ 5 +-----v-----+ 6 +------------+ -| Policy +------> Orchestrator +-----> Evaluator +------> Evaluation | -| Repository | +-------+--------+ +-----^-----+ | Results | -+------------+ | | | Repository | - | 3 | +------------+ - | | 5.2 - +----------|--------+ | - | +--------v------+ | | - | | Collector | | | - | +-------+-------+ | 4 +------------+ - | | +-------> Posture | - | +-------+-------+ | | Attribute | - | | Target System | | | Repository | - | +---------------+ | +------------+ - +-------------------+ - Collection Sub-Architecture ++-------------+ +----------------+ +------------------+ +------------+ +| 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 4: Configuration Assessment Component Interactions + Figure 5: Configuration Assessment Component Interactions - Figure 4 depicts configuration assessment components and their + Figure 5 depicts configuration assessment components and their interactions, which are further described below. - 1. Policy is stored in the Policy Repository: TODO - add specific - interaction options here. + 1. A policy feed provides a configuration assessment policy payload + to the Integration Service. - 2. The Orchestrator obtains collection information from the Policy - Repository: TODO - add specific interaction options here. + 2. The Policy Repository, a consumer of Policy Feed information, + receives and persists the Policy Feed's payload. - 3. The Orchestrator initiates collection to be performed by the - Collection Sub-Architecture: TODO - add specific interaction - options here. + 3. Orchestration component(s), either manually invoked, scheduled, + or event-based, publish a payload to begin the configuration + assessment process. - 4. Collected posture attributes are stored n the Posture Attribute - Repository: TODO - add specific interaction options here. + 4. If necessary, Collection Sub-Architecture components may be + invoked to collect neeeded posture attribute information. - 5. The Orchestrator initiates the Evaluator (optionally with - evaluation information gathered from the Policy Repository): TODO - - add specific interaction options here + 5. If necessary, the Collection Sub-Architecture will provide + collected posture attributes to the Integration Service for + persistence to the Posture Attribute Repository. - 1. The Evaluator obtains evaluation information from the Policy - Repository (optionally): TODO - add specific interaction - options here + 6. The Posture Attribute Repository will consume a payload querying + for relevant posture attribute information. - 2. The Evaluator obtains relevant posture attributes from the - Posture Attribute Repository: TODO - add specific interaction - options here + 7. The Posture Attribute Repository will provide the requested + information to the Integration Service, allowing further + orchestration payloads requesting the Evaluation Sub- + Architecture perform evaluation tasks. - 6. Evaluation results are stored in the Evaluation Results - Repository: TODO - add specific interaction options here + 8. The Evaluation Sub-Architecture consumes the evaluation payload + and performs component-specific state comparison operations to + produce evaluation results. + + 9. A payload containing evaluation results are provided by the + Evaluation Sub-Architecture to the Integration Service + + 10. Evaluation results are consumed by/persisted to the Evaluation + Results Repository In the above flow, the payload information is expected to convey the context required by the receiving component for the action being - taken under different circumstances. For example, the Tell message + taken under different circumstances. For example, a directed message sent from an Orchestrator to a Collection sub-architecture might be telling that Collector to watch a specific posture attribute and report only specific detected changes to the Posture Attribute Repository, or it might be telling the Collector to gather that posture attribute immediately. Such details are expected to be handled as part of that payload, not as part of the architecture described herein. -9. Privacy Considerations +6. Privacy Considerations TODO -10. Security Considerations +7. Security Considerations TODO -11. IANA Considerations +8. IANA Considerations TODO: Revamp this section after the configuration assessment workflow is fleshed out. IANA tables can probably be used to make life a little easier. We would like a place to enumerate: o Capability/operation semantics o SACM Component implementation identifiers @@ -737,31 +806,30 @@ TODO: Revamp this section after the configuration assessment workflow is fleshed out. IANA tables can probably be used to make life a little easier. We would like a place to enumerate: o Capability/operation semantics o SACM Component implementation identifiers - o SACM Component versions o Associations of SACM Components (and versions) to specific Capabilities o Collection sub-architecture Identification -12. References +9. References -12.1. Normative 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), June 2019. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . @@ -771,31 +839,31 @@ Attributes (SWIMA) for PA-TNC", RFC 8412, DOI 10.17487/RFC8412, July 2018, . [RFC8600] Cam-Winget, N., Ed., Appala, S., Pope, S., and P. Saint- Andre, "Using Extensible Messaging and Presence Protocol (XMPP) for Security Information Exchange", RFC 8600, DOI 10.17487/RFC8600, June 2019, . -12.2. Informative References +9.2. Informative References [CISCONTROLS] "CIS Controls v7.0", n.d., . [draft-birkholz-sacm-yang-content] Birkholz, H. and N. Cam-Winget, "YANG subscribed notifications via SACM Statements", n.d., - . + . [HACK100] "IETF 100 Hackathon - Vulnerability Scenario EPCP+XMPP", n.d., . [HACK101] "IETF 101 Hackathon - Configuration Assessment XMPP", n.d., . [HACK102] "IETF 102 Hackathon - YANG Collection on Traditional Endpoints", n.d., @@ -1062,23 +1131,23 @@ Evaluator Repository | | | | | | +------+ +--------+ | +-----------+ |<-------| +-----------+ | | | | | | | Posture | | report | | Posture | | | | | | | | Collection| | | | Collection| | | |<-----> | |<-----| | Manager | | query | | Engine | | | |request/| | store| +-----------+ |------->| +-----------+ | | |respond | | | | | | | | | | | | | | +------+ +--------+ +---------------+ +---------------+ - Figure 5: EPCP Collection Architecture + Figure 6: EPCP Collection Architecture - In Figure 5, any of the communications between the Posture Manager + In Figure 6, any of the communications between the Posture Manager and EPCP components to its left could be performed directly or indirectly using a given message transfer mechanism. For example, the pub/sub interface between the Orchestrator and the Posture Manager could be using a proprietary method or using [RFC8600] or some other pub/sub mechanism. Similarly, the store connection from the Posture Manager to the Repository could be performed internally to a given implementation, via a RESTful API invocation over HTTPS, or even over a pub/sub mechanism. Our assertion is that the Evaluator, Repository, Orchestrator, and @@ -1164,32 +1233,32 @@ extend the core XMPP structure to allow OVAL collection instructions (OVAL objects) to inform posture attribute collection. Collected system characteristics can be provided to the Concise MAP XMPP adapter using all 3 available XMPP capabilities: Publish/Subscribe, Information Query (iq - request/ response) stanzas, or direct Message stanzas. CDDL was created to map collected posture attributes to Concise MAP structure. The XMPP adapter translates the incoming system characteristics and stores the information in the MAP. - Figure 6 depicts a slightly more detailed view of the architecture + Figure 7 depicts a slightly more detailed view of the architecture (within the enterprise boundary) - one that fosters the development of a pluggable ecosystem of cooperative tools. Existing collection mechanisms can be brought into this architecture by specifying the interface of the collector and creating the XMPP-Grid Connector binding for that interface. - Additionally, while not directly depicted in Figure 6, this + Additionally, while not directly depicted in Figure 7, this architecture does allow point-to-point interfaces. In fact, [RFC8600] provides brokering capabilities to facilitate such point- to-point data transfers). Additionally, each of the SACM Components - depicted in Figure 6 may be a provider, a consumer, or both, + depicted 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 | +------------------------^------------------+ +-----------------+ @@ -1197,39 +1266,39 @@ | +-------v------+ | XMPP-Grid | | Connector(s) | +------^-------+ | +------v-------+ | Collector(s) | +--------------+ - Figure 6: XMPP-based Architecture + Figure 7: XMPP-based Architecture [RFC8600] details a number of XMPP extensions (XEPs) that MUST be utilized to meet the needs of [RFC7632] and [RFC8248]: o Service Discovery (XEP-0030): Service Discovery allows XMPP entities to discover information about other XMPP entities. Two kinds of information can be discovered: the identity and capabilities of an 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 service and publish 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, and there are other XMPP extensions (XEPs) we need to consider to - meet the needs of [RFC7632] and [RFC8248]. In Figure 6 we therefore + meet the needs of [RFC7632] and [RFC8248]. In Figure 7 we therefore use "XMPP-Grid+" to indicate something more than [RFC8600] alone, even though we are not yet 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 defines the methods for broadcasting and dynamically discovering an entities' capabilities. This information is transported via standard XMPP presence. Example capabilities that could be discovered could @@ -1295,31 +1364,31 @@ useful in intermittent connection scenarios, or when entities disconnect and reconnect to the ecosystem. o PubSub Chaining (XEP-0253): This extension describes the federation of publishing nodes, enabling a publish node of one server to be a subscriber to a publishing node of another server. C.1. Example Architecture using XMPP-Grid and Endpoint Posture Collection Protocol - Figure 7 depicts a further detailed view of the architecture + Figure 8 depicts a further detailed view of the architecture including 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************************* Enterprise Boundary ************ +********************v*********************** Boundary of Responsibility ******* * | * * +--------------+ | +-------------------+ +-------------+ * * | Orchestrator | | | Posture Attr Repo | | Policy Repo | * * +------^-------+ | +---------^---------+ +---^---------+ * * | | | | +----------------+ * * | | | | | Downstream Uses| * * | | | | | +-----------+ | * * +------v---------v-----------v---------------v--+ | |Evaluations| | * * | XMPP-Grid <-------> +-----------+ | * * +----------------^-------------------^----------+ | +-----------+ | * @@ -1343,21 +1412,21 @@ * | | | * * | +-----------|-------------------------Endpoint or Endpoint Proxy-------+| * * | |+----------v------------+ +----------------+ +----------------------+ || * * | || Communications Client | | Posture Client | | Posture Collector(s) | || * * | |+-----------------------+ +----------------+ +----------------------+ || * * | +----------------------------------------------------------------------+| * * +-----------------Endpoint Posture Collection Profile---------------------+ * * * ******************************************************************************* - Figure 7: XMPP-based Architecture including EPCP + Figure 8: XMPP-based Architecture including EPCP Authors' Addresses Adam W. Montville Center for Internet Security 31 Tech Valley Drive East Greenbush, NY 12061 USA Email: adam.montville.sdo@gmail.com