SACM Working Group A. Montville
Internet-Draft B. Munyan
Intended status: Standards Track CIS
Expires: September 29, 2018 March 28, 2018
Security Automation and Continuous Monitoring (SACM) Architecture
draft-mandm-sacm-architecture-01
Abstract
This memo documents an exploration of a possible Security Automation
and Continuous Monitoring (SACM) architecture. This work is built
upon [I-D.ietf-mile-xmpp-grid], and 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].
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
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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 September 29, 2018.
Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
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include Simplified BSD License text as described in Section 4.e of
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the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Open Questions . . . . . . . . . . . . . . . . . . . . . 3
1.2. Requirements notation . . . . . . . . . . . . . . . . . . 3
2. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 4
3. Architectural Discovery . . . . . . . . . . . . . . . . . . . 4
3.1. SACM Roles . . . . . . . . . . . . . . . . . . . . . . . 5
3.2. Exploring An XMPP-based Solution . . . . . . . . . . . . 5
4. Components, Capabilities, Interfaces, and Workflows . . . . . 7
4.1. Components . . . . . . . . . . . . . . . . . . . . . . . 7
4.2. Capabilities . . . . . . . . . . . . . . . . . . . . . . 8
4.3. Interfaces . . . . . . . . . . . . . . . . . . . . . . . 9
4.4. (Candidate) Workflows . . . . . . . . . . . . . . . . . . 9
4.4.1. Vulnerability Management . . . . . . . . . . . . . . 9
4.4.2. Configuration Management . . . . . . . . . . . . . . 9
4.4.3. IT Asset Management . . . . . . . . . . . . . . . . . 9
5. Privacy Considerations . . . . . . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
8.1. Normative References . . . . . . . . . . . . . . . . . . 10
8.2. Informative References . . . . . . . . . . . . . . . . . 10
Appendix A. Mapping to RFC8248 . . . . . . . . . . . . . . . . . 12
Appendix B. Example Components . . . . . . . . . . . . . . . . . 15
B.1. Policy Services . . . . . . . . . . . . . . . . . . . . . 15
B.2. Software Inventory . . . . . . . . . . . . . . . . . . . 16
B.3. Datastream Collection . . . . . . . . . . . . . . . . . . 17
B.4. Network Configuration Collection . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
The purpose of this draft is to document and track the outcome of
solution discovery, with the intent of eventually describing an
emerged architecture. We have initially built our partial solution
upon [I-D.ietf-mile-xmpp-grid] and [I-D.ietf-sacm-ecp], and believe
these approaches complement each other to more completely meet the
spirit of [RFC7632] and requirements found in [RFC8248].
This solution gains the most advantage by supporting a variety of
collection mechanisms. In this sense, our solution ideally intends
to enable a cooperative ecosystem of tools from disparate sources
with minimal operator configuration. The solution described in this
document seeks to accommodate these recognitions by first defining a
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generic abstract architecture, then making that solution somewhat
more concrete.
Keep in mind that, at this point, the draft is tracking ongoing work
being performed primarily around and during IETF hackathons. The
list of hackathon efforts follows:
o [HACK99]: TODO: Provide description.
o [HACK100]: TODO: Provide description.
o [HACK101]: TODO: Provide description.
1.1. Open Questions
The following is a list of open questions we still have about the
path forward with this exploration:
o What are the specific components participating in a SACM Domain?
o What are the capabilities we can expect these components to
contain?
* How can we classify these capabilities?
* How do we define an extensible capability taxonomy (perhaps
using IANA tables)?
o What are the present-day workflows we expect an operational
enterprise to carry out?
* Can we prioritize these workflows in some way that helps us
progress sensibly?
* How can these workflows be improved?
* Is it a straight path to improvement?
o Should workflows be documented in this draft or separate drafts?
o Should interfaces be documented in workflow drafts or separate
drafts (or even this draft)?
1.2. Requirements notation
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
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"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 Discovery
The generic approach proposed herein recognizes the need to pull
information from existing state collection mechanisms, 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.
+----------+ +------+ +------------+
|Repository| |Policy| |Orchestrator|
+----^-----+ +--^---+ +----^-------+ +----------------+
A | B | C | | Downstream Uses|
| | | | +-----------+ |
+----v---------------v------------v-------+ | |Evaluations| |
| Message Transfer <-------> +-----------+ |
+----------------^------------------------+ D | +---------+ |
| | |Analytics| |
| | +---------+ |
+-------v--------- | +---------+ |
| Transfer System | | |Reporting| |
| Connector | | +---------+ |
+-------^---------+ +----------------+
|
|
+-------v-------+
| Collection |
| System |
+---------------+
Figure 1: Notional Architecture
As shown in Figure 1, the notional SACM architecture consists of some
basic SACM Components using a message transfer system to communicate.
While not depicted, the message transfer system is expected to
maximally align with the requirements described in [RFC8248], which
means that the message transfer system will support brokered (i.e.
point-to-point) and proxied data exchange.
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Additionally, component-specific interfaces (i.e. such as A, B, C,
and D in Figure 1) are expected to be specified logically then bound
to one or more specific implementations. This should be done for
each capability related to the given SACM Component.
3.1. SACM Roles
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 of several roles relevant to the ecosystem. Generally each
role is either a consumer of information or a provider of
information. The "Components, Capabilities, Interfaces, and
Workflows" section provides more details about SACM Components that
play these types of roles.
3.2. Exploring An XMPP-based Solution
In Figure 2, we have a more detailed view of the architecture - one
that fosters the development of a pluggable ecosystem of cooperative
tools. Existing collection mechanisms (ECP/SWIMA included) 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 2, this
architecture does allows point-to-point interfaces. In fact,
[I-D.ietf-mile-xmpp-grid] provides brokering capabilities to
facilitate such point-to-point data transfers). Additionally, each
of the SACM Components depicted in Figure 2 may be a provider, a
consumer, or both, depending on the workflow in context.
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+----------+ +------+ +------------+
|Repository| |Policy| |Orchestrator|
+----^-----+ +--^---+ +----^-------+
| | |
| | |
+----v---------------v------------v-----------------+ +-----------------+
| XMPP-Grid+ <-----> Downstream Uses |
+-----^-------------^-------------^-------------^---+ +-----------------+
| | | |
| | | |
+----v----+ +----v----+ +----v----+ +----v----+
|XMPP-Grid| |XMPP-Grid| |XMPP-Grid| |XMPP-Grid|
/~~|Connector|~~~|Connector|~~~|Connector|~~~|Connector|~~\
| +----^----+ +----^----+ +----^----+ +----^----+ |
| | | | | |
| +----v----+ +----v-----+ +----v----+ +----v----+ |
| |ECP/SWIMA| |Datastream| |YANG Push| | IPFIX | |
| +---------+ +----------+ +---------+ +---------+ |
| Collectors |
\~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~/
Figure 2: Detailed Architecture
At this point, [I-D.ietf-mile-xmpp-grid] 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 2 we therefore use "XMPP-Grid+" to indicate something more
than [I-D.ietf-mile-xmpp-grid] 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)
[I-D.ietf-mile-xmpp-grid] to include additional XEPs - possibly the
following:
o Entity Capabilities (XEP-0115): May be used to express the
specific capabilities that a particular client embodies.
o Form Discovery and Publishing (XEP-0346): May be used for
datastream examples requiring some expression of a request
followed by an expected response.
o Ad Hoc Commands (XEP-0050): May be usable for simple orchestration
(i.e. "do assessment").
o File Repository and Sharing (XEP-0214): Appears to be needed for
handling large amounts of data (if not fragmenting).
o Publishing Stream Initiation Requests (XEP-0137): Provides ability
to stream information between two XMPP entities.
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o PubSub Collection Nodes (XEP-0248): Nested topics for
specialization to the leaf node level.
o Security Labels In Pub/Sub (XEP-0314): Enables tagging data with
classification categories.
o PubSub Since (XEP-0312): Persists published items, which may be
useful in intermittent connection scenarios
o PubSub Chaining (XEP-0253): Federation of publishing nodes
enabling a publish node of one server to be a subscriber to a
publishing node of another server
o Easy User Onboarding (XEP-401): Simplified client registration
4. Components, Capabilities, Interfaces, and Workflows
The SACM Architecture consists of a variety of SACM Components, and
named components are intended to embody one or more specific
capabilities. Interacting with these capabilities will require at
least two levels of interface specification. The first is a logical
interface specification, and the second is at least one binding to a
specific transfer mechanism. At this point, we have been
experimenting with XMPP as a transfer mechanism.
The following subsections describe some of the components,
capabilities, and interfaces we may expect to see participating in a
SACM Domain.
4.1. Components
The following is a list of suggested SACM Component classes and
specializations.
o Repository
* Vulnerability Information Repository
* Asset Inventory Repository
+ Software Inventory Repository
+ Device Inventory Repository
* Configuration Policy Repository
* Configuration State Repository
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o Collector
* Vulnerability State Collector
* Asset Inventory Collector
+ Software Inventory Collector
+ Device Inventory Collector
* Configuration State Collector
o Evaluator
* Vulnerability State Evaluator
* Asset Inventory Evaluator
+ Software Inventory Evaluator
+ Device Inventory Evaluator
* Configuration State Evaluator
o Orchestrator
* Vulnerability Management Orchestrator
* Asset Management Orchestrator
+ Software Inventory Evaluator
+ Device Inventory Evaluator
* Configuration Management Orchestrator
4.2. Capabilities
Repositories will have a need for fairly standard CRUD operations and
query by attribute operations. Collector interfaces may enable ad
hoc assessment (on-demand processing), state item watch actions (i.e.
watch a particular item for particular change), persisting other
behaviors (i.e. setting some mandatory reporting period). Evaluators
may have their own set of interfaces, and an Assessor would represent
both Collector and Evaluation interfaces, and may have additional
concerns added to an Assessor Interface.
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Not to be overlooked, whatever solution at which we arrive must, per
[RFC8248], MUST support capability negotiation. While not explicitly
treated here, each interface will understand specific serializations,
and other component needs to express those serializations to other
components.
4.3. Interfaces
Interfaces should be derived directly from identified workflows,
several of which are described in this document.
4.4. (Candidate) Workflows
The workflows described in this document should be considered as
candidate workflows - informational for the purpose of discovering
the necessary components and specifying their interfaces.
4.4.1. Vulnerability Management
TODO: Pull in some vulnerability management scenario text.
4.4.2. Configuration Management
TODO: Describe configuration management workflow (from policy
creation to implementation to routine assessment).
4.4.3. IT Asset Management
TODO: Describe some ideas surrounding the notion of managing
technology assets. For example, we may consider software inventory
for:
o Agent-based devices
o Non-agent based devices
o Virtual/Cloud environments (public/private) including containers
o Mobile devices
o Devices that are intermittently connected
Ideally, this would provide hardware identification as well.
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5. Privacy Considerations
TODO
6. Security Considerations
TODO
7. IANA Considerations
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
8. References
8.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, <https://www.rfc-
editor.org/info/rfc2119>.
8.2. Informative References
[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 ECP+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>.
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[HACK99] "IETF 99 Hackathon - Vulnerability Scenario ECP", n.d.,
<https://www.github.com/sacmwg/vulnerability-scenario/
ietf-hackathon>.
[I-D.ietf-mile-rolie]
Field, J., Banghart, S., and D. Waltermire, "Resource-
Oriented Lightweight Information Exchange", draft-ietf-
mile-rolie-16 (work in progress), December 2017.
[I-D.ietf-mile-xmpp-grid]
Cam-Winget, N., Appala, S., Pope, S., and P. Saint-Andre,
"Using XMPP for Security Information Exchange", draft-
ietf-mile-xmpp-grid-05 (work in progress), February 2018.
[I-D.ietf-sacm-ecp]
Haynes, D., Fitzgerald-McKay, J., and L. Lorenzin,
"Endpoint Compliance Profile", draft-ietf-sacm-ecp-01
(work in progress), January 2018.
[I-D.ietf-sacm-nea-swid-patnc]
Schmidt, C., Haynes, D., Coffin, C., Waltermire, D., and
J. Fitzgerald-McKay, "Software Inventory Message and
Attributes (SWIMA) for PA-TNC", draft-ietf-sacm-nea-swid-
patnc-01 (work in progress), March 2017.
[I-D.ietf-sacm-terminology]
Birkholz, H., Lu, J., Strassner, J., Cam-Winget, N., and
A. Montville, "Security Automation and Continuous
Monitoring (SACM) Terminology", draft-ietf-sacm-
terminology-14 (work in progress), December 2017.
[NIST800126]
Waltermire, D., Quinn, S., Booth, H., Scarfone, K., and D.
Prisaca, "SP 800-126 Rev. 3 - The Technical Specification
for the Security 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., and M. Johnson, "NISTIR
7694 Specification for Asset 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>.
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[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 Automation and
Continuous Monitoring (SACM) Requirements", RFC 8248,
DOI 10.17487/RFC8248, September 2017, <https://www.rfc-
editor.org/info/rfc8248>.
[XMPPEXT] "XMPP Extensions", n.d., <https://xmpp.org/extensions/>.
Appendix A. Mapping to RFC8248
This section provides a mapping of XMPP and XMPP Extensions to the
relevant requirements from [RFC8248]. In the table below, the ID and
Name columns provide the ID and Name of the requirement directly out
of [RFC8248]. The Supported By column may contain one of several
values:
o N/A: The requirement is not applicable to this 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 satisfied by a core XMPP feature
o XEP-nnnn: The requirement is satisfied by a numbered XMPP
extension (see [XMPPEXT])
o Operational: The requirement is an operational concern or can be
addressed by an operational deployment
o Implementation: The requirement is an implementation concern
If there is no entry in the Supported 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 |
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| | | |
| 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 Location and Network Topology | |
| | | |
| G-014 | Target Endpoint Identity | XMPP-Core |
| | | |
| G-015 | Data Access Control | |
| | | |
| ARCH-001 | Component Functions | XMPP |
| | | |
| ARCH-002 | Scalability | XMPP-Core |
| | | |
| ARCH-003 | Flexibility | XMPP-Core |
| | | |
| ARCH-004 | Separation of Data and Management | |
| | 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 | Extensible Attribute Vocabulary | N/A |
| | | |
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| IM-002 | Posture Data 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 | Singularity and Modularity | 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 | N/A |
| | | |
| DM-013 | Multiple Collectors | N/A |
| | | |
| DM-014 | Attribute Extensibility | N/A |
| | | |
| DM-015 | Solicited vs. Unsolicited Updates | N/A |
| | | |
| DM-016 | Transfer Agnostic | N/A |
| | | |
| OP-001 | Time Synchronization | |
| | | |
| OP-002 | Collection Abstraction | |
| | | |
| OP-003 | Collection Composition | |
| | | |
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| OP-004 | Attribute-Based Query | |
| | | |
| OP-005 | Information-Based Query with Filtering | |
| | | |
| 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
B.1. Policy Services
Consider a policy server conforming to [I-D.ietf-mile-rolie].
[I-D.ietf-mile-rolie] describes a RESTful way based on the ATOM
Publishing Protocol ([RFC5023]) to find specific data collections.
While this represents a specific binding (i.e. RESTful API based on
[RFC5023]), there is a more abstract way to look at ROLIE.
ROLIE provides notional workspaces and collections, and provides the
concept of information categories and links. 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, and so on) to a specific
mechanism (namely an ATOM Publication Protocol extension).
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 [I-D.ietf-mile-rolie] server were external to an
organization, there would be a need for a policy source inside the
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organization as well, and it may be preferred for such a policy
source to be connected directly to the ecosystem's communication
infrastructure.
B.2. Software Inventory
The SACM working group has accepted work on the Endpoint Compliance
Profile [I-D.ietf-sacm-ecp], which describes a collection
architecture and may 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 | | Posture | |
| | | | | | Collection| | | | Collection| |
| |<-----> | |<-----| | Manager | | query | | Engine | |
| |request/| | store| +-----------+ |------->| +-----------+ |
| |respond | | | | | |
| | | | | | | |
+------+ +--------+ +---------------+ +---------------+
Figure 3: ECP Collection Architecture
In Figure 3, any of the communications between the Posture Manager
and ECP 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
[I-D.ietf-mile-xmpp-grid] 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
Posture Manager all have the potential to represent SACM Components
with specific capability interfaces that can be logically specified,
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then bound to one or more specific transfer mechanisms (i.e. RESTful
API, [I-D.ietf-mile-rolie], [I-D.ietf-mile-xmpp-grid], and so on).
B.3. Datastream Collection
[NIST800126], also known as SCAP 1.3, provides the technical
specifications for a "datastream collection". The specification
describes the "datastream collection" as being "composed of SCAP data
streams and SCAP source components". A "datastream" provides an
encapsulation of the SCAP source components required to, for example,
perform configuration assessment on a given endpoint. These source
components include XCCDF checklists, OVAL Definitions, and CPE
Dictionary information. A single "datastream collection" may
encapsulate multiple "datastreams", and reference any number of SCAP
components. Datastream collections were intended to provide an
envelope enabling transfer of SCAP data more easily.
The [NIST800126] specification also defines the "SCAP result data
stream" 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 do is specify the interface for finding or
acquiring source datastream information, nor an interface for
publishing result information. Discovering the actual resources for
this information could be done via ROLIE, as described in the Policy
Services section above, but other repositories of SCAP data exist as
well.
B.4. Network Configuration Collection
[draft-birkholz-sacm-yang-content] illustrates a SACM Component
incorporating a YANG Push client function and an XMPP-grid publisher
function. [draft-birkholz-sacm-yang-content] further states "the
output of the YANG Push client function is encapsulated in a SACM
Content Element envelope, which is again encapsulated in a SACM
statement envelope" which are published, essentially, via an XMPP-
Grid Connector for SACM Components also part of the XMPP-Grid.
This is a specific example of an existing collection mechanism being
adapted to the XMPP-Grid message transfer system.
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Authors' Addresses
Adam W. Montville
Center for Internet Security
31 Tech Valley Drive
East Greenbush, NY 12061
USA
Email: adam.w.montville@gmail.com
Bill Munyan
Center for Internet Security
31 Tech Valley Drive
East Greenbush, NY 12061
USA
Email: bill.munyan.ietf@gmail.com
Montville & Munyan Expires September 29, 2018 [Page 18]
