--- 1/draft-ietf-mile-rolie-10.txt 2017-10-20 09:13:19.255343831 -0700 +++ 2/draft-ietf-mile-rolie-11.txt 2017-10-20 09:13:19.343345911 -0700 @@ -1,20 +1,20 @@ MILE Working Group J. Field Internet-Draft Pivotal Intended status: Standards Track S. Banghart -Expires: April 1, 2018 D. Waltermire +Expires: April 22, 2018 D. Waltermire NIST - September 28, 2017 + October 19, 2017 Resource-Oriented Lightweight Information Exchange - draft-ietf-mile-rolie-10 + draft-ietf-mile-rolie-11 Abstract This document defines a resource-oriented approach for security automation information publication, discovery, and sharing. Using this approach, producers may publish, share, and exchange representations of software descriptors, security incidents, attack indicators, software vulnerabilities, configuration checklists, and other security automation information as web-addressable resources. Furthermore, consumers and other stakeholders may access and search @@ -39,21 +39,21 @@ 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 April 1, 2018. + This Internet-Draft will expire on April 22, 2018. Copyright Notice Copyright (c) 2017 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 @@ -68,65 +68,65 @@ 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 3. XML-related Conventions . . . . . . . . . . . . . . . . . . . 4 3.1. XML Namespaces . . . . . . . . . . . . . . . . . . . . . 4 3.2. RELAX NG Compact Schema . . . . . . . . . . . . . . . . . 5 4. Background and Motivation . . . . . . . . . . . . . . . . . . 5 5. ROLIE Requirements for the Atom Publishing Protocol . . . . . 6 5.1. AtomPub Service Documents . . . . . . . . . . . . . . . . 7 5.1.1. Use of the "app:workspace" Element . . . . . . . . . 7 5.1.2. Use of the "app:collection" Element . . . . . . . . . 8 - 5.1.3. Service Discovery . . . . . . . . . . . . . . . . . . 9 - 5.2. AtomPub Category Documents . . . . . . . . . . . . . . . 9 - 5.3. Transport Layer Security . . . . . . . . . . . . . . . . 10 - 5.4. User Authentication and Authorization . . . . . . . . . . 11 - 5.5. / (forward slash) Resource URL . . . . . . . . . . . . . 11 - 5.6. HTTP methods . . . . . . . . . . . . . . . . . . . . . . 12 - 6. ROLIE Requirements for the Atom Syndication Format . . . . . 12 - 6.1. Use of the "atom:feed" element . . . . . . . . . . . . . 12 - 6.1.1. Use of the "atom:category" Element . . . . . . . . . 13 - 6.1.2. Use of the "atom:link" Element . . . . . . . . . . . 14 - 6.1.3. Use of the "atom:updated" Element . . . . . . . . . . 15 - 6.2. Use of the "atom:entry" Element . . . . . . . . . . . . 15 - 6.2.1. Use of the "atom:content" Element . . . . . . . . . . 16 - 6.2.2. Use of the "atom:link" Element . . . . . . . . . . . 17 - 6.2.3. Use of the "rolie:format" Element . . . . . . . . . . 17 - 6.2.4. Use of the rolie:property Element . . . . . . . . . . 18 - 6.2.5. Requirements for a Standalone Entry . . . . . . . . . 19 - 7. Available Extension Points Provided by ROLIE . . . . . . . . 20 - 7.1. The Category Extension Point . . . . . . . . . . . . . . 20 - 7.1.1. General Use of the "atom:category" Element . . . . . 21 + 5.1.3. Service Document Discovery . . . . . . . . . . . . . 9 + 5.2. Category Documents . . . . . . . . . . . . . . . . . . . 9 + 5.3. Transport Layer Security . . . . . . . . . . . . . . . . 9 + 5.4. User Authentication and Authorization . . . . . . . . . . 10 + 5.5. / (forward slash) Resource URL . . . . . . . . . . . . . 10 + 5.6. HTTP methods . . . . . . . . . . . . . . . . . . . . . . 11 + 6. ROLIE Requirements for the Atom Syndication Format . . . . . 11 + 6.1. Use of the "atom:feed" element . . . . . . . . . . . . . 11 + 6.1.1. Use of the "atom:category" Element . . . . . . . . . 12 + 6.1.2. Use of the "atom:link" Element . . . . . . . . . . . 13 + 6.1.3. Use of the "atom:updated" Element . . . . . . . . . . 14 + 6.2. Use of the "atom:entry" Element . . . . . . . . . . . . 14 + 6.2.1. Use of the "atom:content" Element . . . . . . . . . . 15 + 6.2.2. Use of the "atom:link" Element . . . . . . . . . . . 16 + 6.2.3. Use of the "rolie:format" Element . . . . . . . . . . 16 + 6.2.4. Use of the rolie:property Element . . . . . . . . . . 17 + 6.2.5. Requirements for a Standalone Entry . . . . . . . . . 18 + 7. Available Extension Points Provided by ROLIE . . . . . . . . 19 + 7.1. The Category Extension Point . . . . . . . . . . . . . . 19 + 7.1.1. General Use of the "atom:category" Element . . . . . 20 7.1.2. Identification of Security Automation Information - Types . . . . . . . . . . . . . . . . . . . . . . . . 21 - 7.2. The "rolie:format" Extension Point . . . . . . . . . . . 22 - 7.3. The Link Relation Extension Point . . . . . . . . . . . . 23 - 7.4. The "rolie:property" Extension Point . . . . . . . . . . 23 - 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24 - 8.1. XML Namespaces and Schema URNs . . . . . . . . . . . . . 24 - 8.2. ROLIE URN Sub-namespace . . . . . . . . . . . . . . . . . 25 - 8.3. ROLIE URN Parameters . . . . . . . . . . . . . . . . . . 25 - 8.4. ROLIE Security Resource Information Type Sub-Registry . . 28 - 8.5. Well-Known URI Registrations . . . . . . . . . . . . . . 28 - 9. Security Considerations . . . . . . . . . . . . . . . . . . . 29 - 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 31 - 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 32 - 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 32 - 12.1. Normative References . . . . . . . . . . . . . . . . . . 32 - 12.2. Informative References . . . . . . . . . . . . . . . . . 34 - 12.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 36 - Appendix A. Relax NG Compact Schema for ROLIE . . . . . . . . . 36 - Appendix B. Examples of Use . . . . . . . . . . . . . . . . . . 37 - B.1. Service Discovery . . . . . . . . . . . . . . . . . . . . 37 - B.2. Feed Retrieval . . . . . . . . . . . . . . . . . . . . . 40 - B.3. Entry Retrieval . . . . . . . . . . . . . . . . . . . . . 42 - Appendix C. Change History . . . . . . . . . . . . . . . . . . . 43 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 46 + Types . . . . . . . . . . . . . . . . . . . . . . . . 20 + 7.2. The "rolie:format" Extension Point . . . . . . . . . . . 21 + 7.3. The Link Relation Extension Point . . . . . . . . . . . . 22 + 7.4. The "rolie:property" Extension Point . . . . . . . . . . 22 + 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23 + 8.1. XML Namespaces and Schema URNs . . . . . . . . . . . . . 23 + 8.2. ROLIE URN Sub-namespace . . . . . . . . . . . . . . . . . 24 + 8.3. ROLIE URN Parameters . . . . . . . . . . . . . . . . . . 24 + 8.4. ROLIE Security Resource Information Type Sub-Registry . . 26 + 8.5. Well-Known URI Registrations . . . . . . . . . . . . . . 27 + 9. Security Considerations . . . . . . . . . . . . . . . . . . . 27 + 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 29 + 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 30 + 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 30 + 12.1. Normative References . . . . . . . . . . . . . . . . . . 30 + 12.2. Informative References . . . . . . . . . . . . . . . . . 33 + 12.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 35 + Appendix A. Relax NG Compact Schema for ROLIE . . . . . . . . . 35 + Appendix B. Examples of Use . . . . . . . . . . . . . . . . . . 36 + B.1. Service Discovery . . . . . . . . . . . . . . . . . . . . 36 + B.2. Feed Retrieval . . . . . . . . . . . . . . . . . . . . . 39 + B.3. Entry Retrieval . . . . . . . . . . . . . . . . . . . . . 41 + Appendix C. Change History . . . . . . . . . . . . . . . . . . . 42 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 45 1. Introduction This document defines a resource-oriented approach to security automation information sharing that follows the Representational State Transfer (REST) architectural style [REST]. In this approach, computer security resources are maintained in web-accessible repositories structured as Atom Syndication Format [RFC4287] Feeds. Within a given Feed, which may be requested by the consumer, representations of specific types of security automation information @@ -208,21 +208,21 @@ "http://www.w3.org/2007/app" and "http://www.w3.org/2005/Atom" namespaces appear in RFC5023 appendix B [RFC5023] and RFC4287 appendix B [RFC4287] respectively. A complete informative RELAX NG Compact Schema for the new elements introduced by ROLIE is provided in Appendix A. 4. Background and Motivation In order to automate security process, tools need access to - sufficient sources of structured, security information that can be + sufficient sources of structured security information that can be used to drive security processes. Thus, security information sharing is one of the core components of automating security processes. Vulnerabilities, configurations, software identification, security incidents, and patch data are just a few of the classes of information that are shared today to enable effective security on a wide scale. However, as the scale of defense broadens as networks become larger and more complex, and the volume of information to process makes humans-in-the-loop difficult to scale, the need for automation and machine-to-machine communication becomes increasingly critical. @@ -326,27 +326,25 @@ In AtomPub, a Workspace, represented by the "app:workspace" element, describes a group of one or more Collections. Building on the AtomPub concept of a Workspace, in ROLIE a Workspace represents an aggregation of Collections pertaining to security automation information resources. This specification does not restrict the number of Workspaces that may be in a Service Document or the specific Collections to be provided within a given Workspace. A ROLIE implementation can host Collections containing both public - and private information entries. It is RECOMMENDED that - implementations segregate public and private Collections into - different app:workspace elements. By doing this, Workspaces that - contain private information can be ignored by clients or can be - omitted from the Service Document provided to a client that lacks the - appropriate privilege to access the set of Collections associated - with the Workspace. + and private information entries. It is suggested that + implementations segregate Collections into different app:workspace + elements by their client access requirements. With proper naming of + workspaces, this reduces the amount of trial and error a human user + would need to utilize to discover accessible Collections. 5.1.2. Use of the "app:collection" Element In AtomPub, a Collection in a Service Document, represented by the "app:collection" element, provides metadata that can be used to point to a specific Atom Feed that contains information Entries that may be of interest to a client. The association between a Collection and a Feed is provided by the "href" attribute of the app:collection element. Building on the AtomPub concept of a Collection, in ROLIE a Collection represents a pointer to a group of security automation @@ -387,152 +385,106 @@ Atom Feed resource referenced by the app:collection "href" attribute value. This ensures that the category metadata associated with the Collection and the associated Feed is discoverable in both of these resources. o The app:categories element in an app:collection MAY include additional atom:category elements using a scheme other than "urn:ietf:params:rolie:category:information-type". This allows other category metadata to be included. -5.1.3. Service Discovery +5.1.3. Service Document Discovery - This specification requires that an implementation MUST publish an + ..his specification requires that an implementation MUST publish an Atom Service Document that describes the set of security information Collections provided by the service. The Service Document MUST be retrievable using the standardized URI template "https://{host:port}/.well-known/rolie/servicedocument", where {host:port} is the authority portion of the URI. Dereferencing this URI MAY result in a redirect based on an appropriate HTTP 3xx status code to direct the client to the actual Service Document. This allows clients to have a well-known location to find a ROLIE service document, while giving implementations flexibility over how the service is deployed. This document registers the "rolie/servicedocument" well-known URI as per [RFC5785] in Section 8.5. A mechanism to determine which host and port to use is not specified in this document. Use of a mechanism such as DNS SRV Records [RFC2782] can provide a secure and reliable discovery mechanism for determining a specific host and port to use for retrieving a Service Document for a given DNS domain. -5.2. AtomPub Category Documents +5.2. Category Documents As described in RFC5023 section 7 [RFC5023], a Category Document is an XML-based document format that allows a client to dynamically - discover the Categories used within AtomPub Service Documents, and - Atom Syndication Feed and Entry documents provided by a publisher. A + discover the Categories used within AtomPub Service Documents, Atom + Syndication Feeds, and Entry documents provided by a publisher. A Category Document consists of one app:categories element that contains a number of inline atom:category elements, or a URI referencing a Category Document. - A ROLIE implementation MUST publish a Category Document that - describes the set of atom:category elements and associated terms - currently used by the service. - - The Category Document MUST be retrievable using the standardized URI - template "https://{host:port}/.well-known/rolie/categorydocument", - where {host:port} is the authority portion of the URI. Dereferencing - this URI MAY result in a redirect based on an appropriate HTTP 3xx - status code to direct the client to the actual Category Document. - This allows clients to have a well-known location to find a ROLIE - category document, while giving implementations flexibility over how - the service is deployed. - - This document registers the "rolie/categorydocument" well-known URI - as per [RFC5785] in Section 8.5. - 5.3. Transport Layer Security - ROLIE is intended to be handled with TLS. The following requirements - have been in part derived from [RFC7589]. - - TLS version 1.2 MUST be supported. TLS 1.2 SHOULD be implemented - according to all recommendations and best practices present in - [RFC7525]. + ROLIE is intended to be handled with TLS. TLS version 1.2 MUST be + supported. TLS 1.2 SHOULD be implemented according to all + recommendations and best practices present in [RFC7525]. It is RECOMMENDED that the most recent published version of TLS is supported. If this version is TLS 1.3 [I-D.ietf-tls-tls13], it is recommended that 0-RTT (Zero Round Trip Time Resumption) is not used, as there is a replay attack that is possible with that option. - The server MUST support certificate-based client authentication. An - implementation MUST support the set of TLS cipher suites that are - REQUIRED by the latest published version of the TLS specification. - An implementation MUST also support the TLS cipher suites that - provide support for mutual authentication of clients and servers. - - During the TLS negotiation, the client MUST carefully examine the - certificate presented by the server to determine if it meets the - client's expectations. Particularly, the client MUST check its - understanding of the server hostname against the server's identity as - presented in the server Certificate message, in order to prevent man- - in-the-middle attacks. Matching is performed according to the rules - laid out in the Security Considerations section of [RFC4642]. If the - match fails, the client MUST either ask for explicit user - confirmation or terminate the connection and indicate the server's - identity is suspect. If the client has external information as to - the expected identity of the server, the hostname check MAY be - omitted. - - Clients MUST verify the binding between the identity of the servers - to which they connect and the public keys presented by those servers. - - Client implementations SHOULD support a certificate validation - approach based on section 6 of [RFC5280]. - - The server MUST be capable of verifying the identity of the client - with certificate-based authentication according to local policy to - ensure that the incoming client request is legitimate before any - configuration or state data is sent to or received from the client. + The server MUST implement certificate-based client authentication. + This MAY be enabled on a workspace by workspace basis. 5.4. User Authentication and Authorization Implementations MUST support user authentication. However, a given - implementation MAY allow user authentication to be disabled on a feed - by feed basis. + implementation MAY allow user authentication to be disabled on a Feed + by Feed, or Workspace by Workspace basis. Servers participating in an information sharing consortium and supporting interactive user logins by members of the consortium SHOULD support client authentication via a federated identity scheme. This document does not mandate the use of any specific user authorization mechanisms. However, service implementers SHOULD - provide appropriate authorization checking for all resource accesses, + support appropriate authorization checking for all resource accesses, including individual Atom Entries, Atom Feeds, and Atom Service Documents. 5.5. / (forward slash) Resource URL The "/" resource MAY be supported for compatibility with existing deployments that are using Transport of Real-time Inter-network Defense (RID) Messages over HTTP/TLS [RFC6546]. - The following additional requirements apply for implementations - supporting handling of the "/" resource:: + The following additional requirements only apply if a implementation + is supporting the "/" resource as described above: o Consistent with RFC6546 errata, a client requesting a GET on the "/" resource SHOULD receive an HTTP status code 405 Method Not Allowed. o An implementation MAY provide full support for [RFC6546] such that a POST to the "/" resource containing a recognized RID message is handled correctly as a RID request. Alternatively, a client requesting a POST to "/" MAY receive an HTTP status code 307 Temporary Redirect. In this case, the location header in the HTTP response will provide the URL of the appropriate RID endpoint, and the client may repeat the POST method at the indicated location. If the "/" resource is unsupported, then a request for this resource - MUST provide a 404 HTTP status code. + MAY be handled as deemed appropriate by the server. 5.6. HTTP methods Servers MAY accept request methods beyond those specified in this document. Clients MUST be capable of recognizing and processing any standard HTTP status code, as defined in [RFC5023] Section 5. 6. ROLIE Requirements for the Atom Syndication Format @@ -607,22 +559,22 @@ & atomTitle & atomUpdated & extensionElement*), atomEntry* } The following subsections contain requirements for a ROLIE Feed. 6.1.1. Use of the "atom:category" Element - An atom:feed can contain zero or more atom:category elements. In - Atom the naming scheme and the semantic meaning of the terms used to + An atom:feed can contain one or more atom:category elements. In Atom + the naming scheme and the semantic meaning of the terms used to identify an Atom category are application-defined. The following are additional requirements on the use of the atom:category element when used in a ROLIE Feed: o All member Entries in the Feed MUST represent security automation information records of the provided information type category. o An atom:feed MAY include additional atom:category elements using a scheme other than "urn:ietf:params:rolie:category:information- @@ -695,27 +647,26 @@ An atom:feed MAY include additional link relationships not specified in this document. If a client encounters an unknown link relationship type, the client MUST ignore the unrecognized link and continue processing as if the unrecognized link element did not appear. The definition of new Link relations that provide additional state transition extensions is discussed in section 7.3. 6.1.3. Use of the "atom:updated" Element - The atom:updated element identifies the date and time that an Entry - was last updated. + The atom:updated element identifies the date and time that a Feed was + last updated. The atom:updated element MUST be populated with the current time at - the instant the Feed representation was last updated by adding, - updating, or deleting an Entry; or changing any metadata for the - Feed. + the instant the Feed was last updated by adding, updating, or + deleting an Entry; or changing any metadata for the Feed. 6.2. Use of the "atom:entry" Element Each Entry in an Atom Feed, represented by the atom:entry element, describes a single referenced information record, along with descriptive information about its format, media type, and other publication metadata. The following atom:entry schema definition represents a stricter representation of the atom:entry element defined in [RFC4287] for use in a ROLIE-based Atom Feed as defined in section 6.1.1. @@ -733,40 +684,46 @@ & atomRights? & atomSource? & atomSummary? & atomTitle & atomUpdated & rolieFormat & rolieProperty* & extensionElement*) } + The notable changes from [RFC4287] are the addition of rolieFormat + and rolieProperty, and atomContent no longer being optional. + The following subsections contain requirements for Entries in a ROLIE Feed. 6.2.1. Use of the "atom:content" Element An atom:content element associates its containing Entry with a content resource identified by the src attribute. There MUST be exactly one atom:content element in the Entry. The content element MUST adhere to this definition, which is a stricter representation of the atom:content element defined in [RFC4287]: atomContent = element atom:content { atomCommonAttributes, attribute type { atomMediaType }, attribute src { atomUri }, empty } + This restricts atomContent in ROLIE to the atomOutofLine forumulation + presented in[RFC4287]. + The type attribute MUST identify the serialization type of the content, for example, application/xml or application/json. A prefixed media type MAY be used to reflect a specific model used with a given serialization approach (e.g., application/rdf+xml). The src attribute MUST be an IRI that can be dereferenced to retrieve the related content data. 6.2.2. Use of the "atom:link" Element Link relations can be included in an atom:entry to represent state @@ -936,26 +893,24 @@ ROLIE further defines the use of the existing Atom extension category mechanism by allowing ROLIE specific category extensions to be registered with IANA, and additionally has assigned the "urn:ietf:params:rolie:category:information-type" category scheme that has special meaning for implementations of ROLIE. This allows category scheme namespaces to be managed in a more consistent way, allowing for greater interoperability between content producers and consumers. - The namespace "urn:ietf:params:rolie:category:local" has been - reserved in the IANA ROLIE Parameters table for private use as - defined in [RFC8126]. Any category whose "scheme" attribute uses - this as a prefix MUST be considered private use. Implementations - encountering such a category MUST parse the content without error, - but MAY otherwise ignore the element. + Any category whose "scheme" attribute uses an unregistered scheme + MUST be considered private use. Implementations encountering such a + category MUST parse the content without error, but MAY otherwise + ignore the element. Use of the "atom:category" element is discussed in the following subsections. 7.1.1. General Use of the "atom:category" Element The atom:category element can be used for characterizing a ROLIE Resource. As discussed earlier in this document, an atom:category element has a "term" attribute that indicates the assigned category value, and a "scheme" attribute that provides an identifier for the @@ -996,21 +951,23 @@ For example, the notional security automation information type "incident" would be identified as follows: A security automation information type represents a class of information that represents the same or similar information model - [RFC3444]. Notional examples of information types include: + [RFC3444]. Note that this document does not register any information + types, but offers the following as examples of potential information + types: indicator: Computing device- or network-related "observable features and phenomenon that aid in the forensic or proactive detection of malicious activity; and associated meta-data" (from [RFC7970]). incident: Information pertaining to and "derived analysis from security incidents" (from [RFC7970]). vulnerability reports: Information identifying and describing a vulnerability in hardware or software. @@ -1085,21 +1042,23 @@ encountering such a property MUST parse the content without error, but MAY otherwise ignore the element. This document also registers a number of general use properties that can be used to expose content information in any ROLIE use case. The following are descriptions of how to use these registered properties: urn:ietf:params:rolie:property:content-author-name The "value" attribute of this property is a text representation indicating the individual or organization that authored the content referenced by - the "src" attribute of the entry's atom:content element. + the "src" attribute of the entry's atom:content element. This + author may differ from the atom:author when the author of the + content and the entry are different people or entities. urn:ietf:params:rolie:property:content-id The "value" attribute of this property is a text representation of an identifier pertaining to or extracted from the content referenced by the "src" attribute of the entry's atom:content element. urn:ietf:params:rolie:property:content-published-date The "value" attribute of this property is a text representation indicating the original publication date of the content referenced by the "src" attribute of the entry's atom:content element. This date may @@ -1215,26 +1175,20 @@ | | | Secti | following location: htt | | | | on | ps://www.iana.org/assig | | | | 8.4 | nments/rolie/category | | | | | /information-type] | | property:l | urn:ietf:params:ro | This | None | | ocal | lie:property:local | docum | | | | | ent, | | | | | Secti | | | | | on | | | | | 7.4 | | - | category:l | urn:ietf:params:ro | This | None | - | ocal | lie:category:local | docum | | - | | | ent, | | - | | | Secti | | - | | | on | | - | | | 7.1 | | | property | urn:ietf:params:ro | This | None | | :content- | lie:property | docum | | | author- | :content-author- | ent, | | | name | name | Secti | | | | | on | | | | | 7.4 | | | property | urn:ietf:params:ro | This | None | | :content- | lie:property | docum | | | id | :content-id | ent, | | | | | Secti | | @@ -1261,22 +1215,23 @@ Name of Registry: "ROLIE Information Types" Location of Registry: https://www.iana.org/assignments/rolie/category/information-type Fields to record in the registry: name: The full name of the security resource information type as a string from the printable ASCII character set [RFC0020] - with individual embedded spaces allowed. The ABNF [RFC5234] - syntax for this field is: + with individual embedded spaces allowed. This value must be + unique in the context of this table. The ABNF [RFC5234] syntax + for this field is: 1*VCHAR *(SP 1*VCHAR) index: This is an IANA-assigned positive integer that identifies the registration. The first entry added to this registry uses the value 1, and this value is incremented for each subsequent entry added to the registry. reference: A list of one or more URIs [RFC3986] from which the registered specification can be obtained. The registered @@ -1294,64 +1249,49 @@ Service Document registration: URI suffix: rolie/servicedocument Change controller: IETF Specification document: This document, Section 5.1.3 Related information: None - Category Document registration: - - URI suffix: rolie/categorydocument - - Change controller: IETF - - Specification document: This document, Section 5.2 - - Related information: None - 9. Security Considerations This document defines a resource-oriented approach for lightweight information exchange using HTTP over TLS, the Atom Syndication Format, and the Atom Publishing Protocol. As such, implementers must understand the security considerations described in those specifications. All that follows is guidance, more specific instruction is out of scope for this document. To protect the confidentiality of a given resource provided by a ROLIE implementation, requests for retrieval of the resource need to be authenticated to prevent unauthorized users from accessing the resource (see section 5.4). It can also be useful to log and audit access to sensitive resources to verify that proper access controls remain in place over time. - The approach described herein is based upon all policy enforcements - being implemented at the point when a resource representation is - created. As such, producers sharing cyber security information using - this specification must take care to authenticate their HTTP clients - using a suitably strong user authentication mechanism. Sharing - communities that are exchanging information on well-known indicators - and incidents for purposes of public education may choose to rely - upon HTTP Authentication or similar. A number of authentication - schemes are defined in the HTTP Authentication Schemes Registry [3]. - Of these, HOBA [RFC7486] and SCRAM-SHA-256 [RFC7804] provide improved - security properties over HTTP Basic [RFC7617]and Digest [RFC7616] - Authentication Schemes. However, sharing communities that are - engaged in sensitive collaborative analysis and/or operational - response for indicators and incidents targeting high value - information systems should adopt a suitably stronger user - authentication solution, such as a risk-based or multi-factor - approach. In general, trust in the sharing consortium will depend - upon the members maintaining adequate user authentication mechanisms. + Access control to information published using ROLIE should use + mechanisms that are appropriate to the sensitivity of the + information. Primitive authentication mechanisms like HTTP Basic + Authentication [RFC7617] are rarely appropriate for sensitive + information. A number of authentication schemes are defined in the + HTTP Authentication Schemes Registry [3]. Of these, HOBA [RFC7486] + and SCRAM-SHA-256 [RFC7804] provide improved security properties over + HTTP Basic [RFC7617]and Digest [RFC7616] Authentication Schemes. + However, sharing communities that are engaged in sensitive + collaborative analysis and/or operational response for indicators and + incidents targeting high value information systems should adopt a + suitably stronger user authentication solution, such as a risk-based + or multi-factor approach. Collaborating consortiums may benefit from the adoption of a federated identity solution, such as those based upon OAuth [RFC6749] with JWT [RFC7797], or SAML-core [SAML-core], SAML-bind [SAML-bind], and SAML-prof [SAML-prof] for Web-based authentication and cross- organizational single sign-on. Dependency on a trusted third party identity provider implies that appropriate care must be exercised to sufficiently secure the Identity provider. Any attacks on the federated identity system would present a risk to the consortium, as a relying party. Potential mitigations include deployment of a @@ -1373,83 +1313,80 @@ policy enforcement requirements relevant to their consortium and/or organization. Additional security requirements such as enforcing message-level security at the destination system could supplement the security enforcements performed at the source system, however these destination-provided policy enforcements are out of scope for this specification. Implementers requiring this capability should consider leveraging, e.g. the element in the RID schema. Refer to RFC6545 section 9 for more information. Additionally, the - underlying serialization approach used in the message (e.g., XML, - JSON) can offer encryption and message authentication capabilities. - For example, XMLDSig [RFC3275] for XML, and JSON Web Encryption - [RFC7516] and JSON Web Signature[RFC7515] for JSON can provide such - mechanisms. + underlying serialization approach used in the representation (e.g., + XML, JSON) can offer encryption and message authentication + capabilities. For example, XMLDSig [RFC3275] for XML, and JSON Web + Encryption [RFC7516] and JSON Web Signature[RFC7515] for JSON can + provide such mechanisms. When security policies relevant to the source system are to be enforced at both the source and destination systems, implementers must take care to avoid unintended interactions of the separately enforced policies. Potential risks will include unintended denial of service and/or unintended information leakage. These problems may be mitigated by avoiding any dependence upon enforcements performed at the destination system. When distributed enforcement is unavoidable, the usage of a standard language (e.g. XACML) for the expression of authorization policies will enable the source and destination systems to better coordinate and align their respective policy expressions. A service discovery mechanism is not explicitly specified in this document, and there are several approaches available for implementers. When selecting this mechanism, implementations need to ensure that their choice provides a means for authenticating the server. As described in the discovery section, DNS SRV Records are a - possible secure solution to discovery. + possible solution to discovery. 10. Privacy Considerations The optional author field may provide an identification privacy issue if populated without the author's consent. This information may become public if posted to a public feed. Special care should be taken when aggregating or sharing entries from other feeds, or when programmatically generating ROLIE entries from some data source that the author's personal info is not shared without their consent. When using the Atom Publishing Protocol to POST entries to a feed, attackers may use correlating techniques to profile the user. The request time can be compared to the generated "updated" field of the entry in order to build out information about a given user. This correlation attempt can be mitigated by not using HTTP requests to POST entries when profiling is a risk, and rather use backend control - of the feeds. + of the Feeds. Adoption of the information sharing approach described in this document will enable users to more easily perform correlations across separate, and potentially unrelated, cyber security information providers. A client may succeed in assembling a data set that would not have been permitted within the context of the authorization policies of either provider when considered individually. Thus, providers may face a risk of an attacker obtaining an access that constitutes an undetected separation of duties (SOD) violation. It is important to note that this risk is not unique to this specification, and a similar potential for abuse exists with any other cyber security information sharing protocol. However, the wide availability of tools for HTTP clients and Atom Feed handling implies that the resources and technical skills required for a successful exploit may be less than it was previously. This risk can be best mitigated through appropriate vetting of the client at account provisioning time. In addition, any increase in the risk of this type of abuse should be offset by the corresponding increase in effectiveness that this specification affords to the defenders. - Proper usage of TLS as described in Section 5.3 will in many cases - aid in the mitigation of these issues. - Overall, ROLIE introduces few privacy concerns above and beyond those present in any other HTTP protocol. Those that exist can be mitigated by following security considerations and carefully using the optional identifying elements. 11. Acknowledgements The authors gratefully acknowledge the valuable contributions of Tom Maguire, Kathleen Moriarty, and Vijayanand Bharadwaj. These individuals provided detailed review comments on earlier drafts, and @@ -1927,20 +1864,25 @@ src="http://www.example.org/provider/vulns/123456/data"> The example response above shows an XML document referenced by the "src" attribute of the atom:content element. The client may retrieve the document using this URL. Appendix C. Change History + Changes in draft-ietf-mile-rolie-11 since draft-ietf-mile-rolie-09 + revision: + + Incorporated ART last call review and AD review changes + Changes in draft-ietf-mile-rolie-09 since draft-ietf-mile-rolie-08 revision: TLS requirements changed to clarify TLS versioning and recommendations Informative references and textual discussion added to Security Considerations around HTTP Authentication and content Signing/ Encryption.