XEP-0268: Incident Handling

Abstract:This specification defines methods for incident reporting among XMPP server deployments using the IODEF format produced by the IETF's INCH Working Group.
Authors:Artur Hefczyc, Florian Jensen, Mickaël Rémond, Peter Saint-Andre, Matthew Wild
Copyright:© 1999 - 2012 XMPP Standards Foundation. SEE LEGAL NOTICES.
Status:Experimental
Type:Standards Track
Version:0.5
Last Updated:2012-05-16

WARNING: This Standards-Track document is Experimental. Publication as an XMPP Extension Protocol does not imply approval of this proposal by the XMPP Standards Foundation. Implementation of the protocol described herein is encouraged in exploratory implementations, but production systems are advised to carefully consider whether it is appropriate to deploy implementations of this protocol before it advances to a status of Draft.

Table of Contents


1. Introduction
2. Interactions
3. Report Format and Processing
4. Inquiry Format and Processing
5. Request Format and Processing
6. Response Format and Processing
7. Internationalization Considerations
8. Security Considerations
9. IANA Considerations
10. XMPP Registrar Considerations
    10.1. Protocol Namespaces
    10.2. Protocol Versioning
11. XML Schema

Appendices
    A: Document Information
    B: Author Information
    C: Legal Notices
    D: Relation to XMPP
    E: Discussion Venue
    F: Requirements Conformance
    G: Notes
    H: Revision History

1. Introduction

As XMPP technologies have been deployed more widely, the open XMPP network has become a more significant target for attacks. This specification defines ways for XMPP server deployments to share information with each other and therefore to handle such attacks in a more real-time fashion. In particular, it defines a way to use the IODEF format (defined in RFC 5070 [1] and produced by the IETF's INCH Working Group) as the basis for sharing incident reports among XMPP server deployments. (For some related considerations, see RFC 2350 [2] and RFC 3067 [3].)

2. Interactions

This document defines several interactions (similar to those in RID, see RFC 6045 [4]) between XMPP server deployments with respect to incident handling. These interactions are transported using the XMPP <iq/> stanza as described below, where each element (qualified by the 'urn:xmpp:incident:2' namespace) is used as a wrapper for IODEF data.

  1. The <report/> element (contained in an <iq/> stanza of type "set") describes the nature of an incident and also flags the 'status' of the incident as "new", "updated", or "resolved"; it is sent from one server to another for informative purposes but without requesting assistance (for which see the <request/> element). This element is similar to a RID message type of "Report".

  2. The <inquiry/> element (contained in an <iq/> stanza of type "get") asks for information about an incident; it is expected that the reply will contain a <report/> element. This element is similar to a RID message type of "IncidentQuery".

  3. The <request/> element (contained in an <iq/> stanza of type "get") asks for assistance in resolving an incident, e.g., by requesting that the server take some action. This element is similar to a RID message type of "Investigation" or "TraceRequest".

  4. The <response/> element (contained in an <iq/> stanza of type "set") provides assistance in resolving an incident. This element is similar to a RID message type of "Result".

3. Report Format and Processing

When one server wants to send information about an incident, it sends a incident report to another server. The report consists of an XMPP <iq/> stanza of type "set" containing a <report/> element that in turn contains an IODEF document. An example is shown below.

Example 1. A report of trouble

<iq from='jabber.org' id='vk2x91g47' to='im.flosoft.biz' type='set'>
  <report xmlns='urn:xmpp:incident:2'>
    <Incident xmlns='urn:ietf:params:xml:ns:iodef-1.0'
              purpose='reporting'>
      <IncidentID name='jabber.org'>4BF5D2CE-7C90-4860-BEF2-43A7D777D5FF</IncidentID>
      <StartTime>2009-04-13T19:05:20Z</StartTime>
      <EndTime>2009-04-13T19:27:22Z</EndTime>
      <ReportTime>2009-04-13T19:31:07Z</ReportTime>
      <Description xml:lang='en'>lots of MUC spammers from clueless.lit!</Description>
      <Contact role='admin' type='person'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:incident:2'>stpeter@jabber.org</jid>
        </AdditionalData>
      </Contact>
      <Contact role='admin' type='person'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:jid:0'>stpeter@jabber.org</jid>
        </AdditionalData>
      </Contact>
      <Contact role='ext-type' ext-type='chatroom'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:jid:0'>operators@muc.xmpp.org</jid>
        </AdditionalData>
      </Contact>
      <RelatedActivity>
        <IncidentID name='im.example.com'>133BCE2E-E669-4ECE-B0F8-766B9E65630D</IncidentID>
      </RelatedActivity>
      <Assessment>
        <Impact lang='en' severity='medium' completion='succeeded' type='dos'/>
      </Assessment>
      <EventData>
        <Flow>
          <System category='source'>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>abuser@clueless.lit</Address>
              <Counter type='ext-type' ext-type='xmpp-presence'>123</Counter>
            </Node>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>luser27@clueless.lit</Address>
              <Counter type='ext-type' ext-type='xmpp-presence'>47</Counter>
            </Node>
          </System>
          <System category='target'>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>jdev@conference.jabber.org</Address>
              <Address category='ext-category' ext-category='xmpp'>jabber@conference.jabber.org</Address>
              <NodeRole category='ext-category' ext-category='xmpp-muc'/>
            </Node>
          </System>
        </Flow>
      </EventData>
    </Incident>
  </report>
</iq>

If the recipient is able to process the report, it MUST return an <iq/> stanza of type "result"; if not, it MUST return an <iq/> stanza of type "error" (error handling will be defined in a future version of this specification).

4. Inquiry Format and Processing

When one server wants to find out more information about an incident, it sends an inquiry to another server (not necessarily the server where the incident occurred).

Example 2. An inquiry about an incident

<iq from='tigase.org' id='br6a31m9' to='im.flosoft.biz' type='get'>
  <inquiry xmlns='urn:xmpp:incident:2'>
    <Incident xmlns='urn:ietf:params:xml:ns:iodef-1.0'
              purpose='traceback'>
      <IncidentID name='jabber.org'>4BF5D2CE-7C90-4860-BEF2-43A7D777D5FF</IncidentID>
    </Incident>
  </inquiry>
</iq>

If the recipient is able to process the inquiry, it MUST return an <iq/> stanza of type "result" and then send a report about the incident using an <iq/> stanza of type "set" as defined above; if not, it MUST return an <iq/> stanza of type "error" (error handling will be defined in a future version of this specification).

5. Request Format and Processing

When one server wants to ask for assistance in resolving an incident, it sends a request to another server (not necessarily the server where the incident occurred).

Here, the server where the attack occurred requests that the server where the attack originated will disable the offending accounts (via the "block-host" value for the 'action' attribute of the IODEF <Expectation/> element).

Example 3. A request for assistance

<iq from='jabber.org' id='kq62vx31' to='clueless.lit' type='get'>
  <request xmlns='urn:xmpp:incident:2'>
    <Incident xmlns='urn:ietf:params:xml:ns:iodef-1.0'
              purpose='mitigation'>
      <IncidentID name='jabber.org'>4BF5D2CE-7C90-4860-BEF2-43A7D777D5FF</IncidentID>
      <StartTime>2009-04-13T19:05:20Z</StartTime>
      <EndTime>2009-04-13T19:27:22Z</EndTime>
      <ReportTime>2009-04-13T19:31:07Z</ReportTime>
      <Description xml:lang='en'>lots of MUC spammers from clueless.lit!</Description>
      <Contact role='admin' type='person'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:incident:2'>stpeter@jabber.org</jid>
        </AdditionalData>
      </Contact>
      <Contact role='admin' type='person'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:jid:0'>stpeter@jabber.org</jid>
        </AdditionalData>
      </Contact>
      <Contact role='ext-type' ext-type='chatroom'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:jid:0'>operators@muc.xmpp.org</jid>
        </AdditionalData>
      </Contact>
      <RelatedActivity>
        <IncidentID name='im.example.com'>133BCE2E-E669-4ECE-B0F8-766B9E65630D</IncidentID>
      </RelatedActivity>
      <Assessment>
        <Impact lang='en' severity='medium' completion='succeeded' type='dos'/>
      </Assessment>
      <EventData>
        <Flow>
          <System category='source'>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>abuser@clueless.lit</Address>
              <Counter type='ext-type' ext-type='xmpp-presence'>123</Counter>
            </Node>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>luser27@clueless.lit</Address>
              <Counter type='ext-type' ext-type='xmpp-presence'>47</Counter>
            </Node>
          </System>
          <System category='target'>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>jdev@conference.jabber.org</Address>
              <Address category='ext-category' ext-category='xmpp'>jabber@conference.jabber.org</Address>
              <NodeRole category='ext-category' ext-category='xmpp-muc'/>
            </Node>
          </System>
        </Flow>
        <Expectation action='block-host'/>
      </EventData>
    </Incident>
  </request>
</iq>

If the recipient is able to process the report, it MUST return an <iq/> stanza of type "result"; if not, it MUST return an <iq/> stanza of type "error" (error handling will be defined in a future version of this specification).

6. Response Format and Processing

When one server provides assistance in resolving an incident, it sends a response to another server (not necessarily the server where the incident occurred).

Here, the server where the attack originated informs the server where the attack occurred that it has disabled the offending accounts (via the IODEF <HistoryItem/> element).

Example 4. A response to a request for assistance

<iq from='clueless.list' id='ic1fa53v' to='jabber.org' type='set'>
  <response xmlns='urn:xmpp:incident:2'>
    <Incident xmlns='urn:ietf:params:xml:ns:iodef-1.0'
              purpose='mitigation'>
      <IncidentID name='jabber.org'>4BF5D2CE-7C90-4860-BEF2-43A7D777D5FF</IncidentID>
      <StartTime>2009-04-13T19:05:20Z</StartTime>
      <EndTime>2009-04-13T19:27:22Z</EndTime>
      <ReportTime>2009-04-13T19:31:07Z</ReportTime>
      <Description xml:lang='en'>lots of MUC spammers from clueless.lit!</Description>
      <Contact role='admin' type='person'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:incident:2'>stpeter@jabber.org</jid>
        </AdditionalData>
      </Contact>
      <Contact role='admin' type='person'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:jid:0'>stpeter@jabber.org</jid>
        </AdditionalData>
      </Contact>
      <Contact role='ext-type' ext-type='chatroom'>
        <AdditionalData>
          <jid xmlns='urn:xmpp:jid:0'>operators@muc.xmpp.org</jid>
        </AdditionalData>
      </Contact>
      <RelatedActivity>
        <IncidentID name='im.example.com'>133BCE2E-E669-4ECE-B0F8-766B9E65630D</IncidentID>
      </RelatedActivity>
      <Assessment>
        <Impact lang='en' severity='medium' completion='succeeded' type='dos'/>
      </Assessment>
      <EventData>
        <Flow>
          <System category='source'>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>abuser@clueless.lit</Address>
              <Counter type='ext-type' ext-type='xmpp-presence'>123</Counter>
            </Node>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>luser27@clueless.lit</Address>
              <Counter type='ext-type' ext-type='xmpp-presence'>47</Counter>
            </Node>
          </System>
          <System category='target'>
            <Node>
              <Address category='ext-category' ext-category='xmpp'>jdev@conference.jabber.org</Address>
              <Address category='ext-category' ext-category='xmpp'>jabber@conference.jabber.org</Address>
              <NodeRole category='ext-category' ext-category='xmpp-muc'/>
            </Node>
          </System>
        </Flow>
        <Expectation action='block-host'/>
      </EventData>
      <History>
        <HistoryItem action='blockquote'>
          <DateTime>2009-04-13T19:47:11Z</DateTime>
          <Description>Account disabled</Description>
        </HistoryItem>
      </History>
    </Incident>
  </response>
</iq>

If the recipient is able to process the report, it MUST return an <iq/> stanza of type "result"; if not, it MUST return an <iq/> stanza of type "error" (error handling will be defined in a future version of this specification).

7. Internationalization Considerations

The <jid/> element qualified by the 'urn:xmpp:incident:2' namespace is a "JID slot" as described in rfc6122bis [5].

8. Security Considerations

It is RECOMMENDED for a server deployment to exchange incident reports only with peer servers that it trusts, for example peers that are in its "server roster" as described in Server Buddies [6].

This technology is designed to help mitigate attacks on the XMPP network. However, incident reporting is itself vulnerable to the following attacks:

Use of the XMPP channel is convenient for communication among XMPP servers; however, if a denial of service attack is severe enough then that channel itself might be unusable.

Unless explicitly configured to do so, a receiving server SHOULD NOT automatically modify its configuration based on receipt of an incident report, even from a trusted server, but instead SHOULD prompt the human administrators so that they can take appropriate action.

A receiving server MAY accept incident reports from peers that are not on its "trust list", but SHOULD treat such reports with caution and provide them to the human administrator(s) of the server.

A receiving server MAY forward reports that it receives to other servers it trusts.

9. IANA Considerations

This document might require interaction with the Internet Assigned Numbers Authority (IANA) [8] to register various IODEF extension attributes.

10. XMPP Registrar Considerations

10.1 Protocol Namespaces

This specification defines the following XML namespace:

Upon advancement of this specification from a status of Experimental to a status of Draft, the XMPP Registrar [9] shall add the foregoing namespace to the registry located at <http://xmpp.org/registrar/namespaces.html>, as described in Section 4 of XMPP Registrar Function [10].

10.2 Protocol Versioning

If the protocol defined in this specification undergoes a revision that is not fully backwards-compatible with an older version, the XMPP Registrar shall increment the protocol version number found at the end of the XML namespaces defined herein, as described in Section 4 of XEP-0053.

11. XML Schema

<?xml version='1.0' encoding='UTF-8'?>

<xs:schema
    xmlns:xs='http://www.w3.org/2001/XMLSchema'
    targetNamespace='urn:xmpp:incident:2'
    xmlns='urn:xmpp:incident:2'
    elementFormDefault='qualified'>

  <xs:import namespace='urn:ietf:params:xml:ns:iodef-1.0'/>

  <xs:element name='jid' type='xs:string'/>

  <xs:element name='inquiry' type='IODEFContainerType'/>
  <xs:element name='report' type='IODEFContainerType'/>
  <xs:element name='request' type='IODEFContainerType'/>
  <xs:element name='response' type='IODEFContainerType'/>

  <xs:complexType name="IODEFContainerType">
    <xs:sequence xmlns:i='urn:ietf:params:xml:ns:iodef-1.0'>
      <xs:element ref='i:Incident' minOccurs='1' maxOccurs='1'/>
    </xs:sequence>
  </xs:complexType>

</xs:schema>

Appendices

Appendix A: Document Information

Series: XEP
Number: 0268
Publisher: XMPP Standards Foundation
Status: Experimental
Type: Standards Track
Version: 0.5
Last Updated: 2012-05-16
Approving Body: XMPP Council
Dependencies: XMPP Core
Supersedes: None
Superseded By: None
Short Name: NOT_YET_ASSIGNED
Source Control: HTML
This document in other formats: XML  PDF

Appendix B: Author Information

Artur Hefczyc

Email: artur.hefczyc@gmail.com
JabberID: artur.hefczyc@tigase.org

Florian Jensen

Email: admin@flosoft.biz
JabberID: admin@im.flosoft.biz

Mickaël Rémond

Email: mickael.remond@process-one.net
JabberID: mremond@process-one.net

Peter Saint-Andre

Email: stpeter@jabber.org
JabberID: stpeter@jabber.org
URI: https://stpeter.im/

Matthew Wild

Email: mwild1@gmail.com
JabberID: me@matthewwild.co.uk

Appendix C: Legal Notices

Copyright

This XMPP Extension Protocol is copyright © 1999 - 2012 by the XMPP Standards Foundation (XSF).

Permissions

Permission is hereby granted, free of charge, to any person obtaining a copy of this specification (the "Specification"), to make use of the Specification without restriction, including without limitation the rights to implement the Specification in a software program, deploy the Specification in a network service, and copy, modify, merge, publish, translate, distribute, sublicense, or sell copies of the Specification, and to permit persons to whom the Specification is furnished to do so, subject to the condition that the foregoing copyright notice and this permission notice shall be included in all copies or substantial portions of the Specification. Unless separate permission is granted, modified works that are redistributed shall not contain misleading information regarding the authors, title, number, or publisher of the Specification, and shall not claim endorsement of the modified works by the authors, any organization or project to which the authors belong, or the XMPP Standards Foundation.

Disclaimer of Warranty

## NOTE WELL: This Specification is provided on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. ##

Limitation of Liability

In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall the XMPP Standards Foundation or any author of this Specification be liable for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising from, out of, or in connection with the Specification or the implementation, deployment, or other use of the Specification (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if the XMPP Standards Foundation or such author has been advised of the possibility of such damages.

IPR Conformance

This XMPP Extension Protocol has been contributed in full conformance with the XSF's Intellectual Property Rights Policy (a copy of which can be found at <http://xmpp.org/about-xmpp/xsf/xsf-ipr-policy/> or obtained by writing to XMPP Standards Foundation, 1899 Wynkoop Street, Suite 600, Denver, CO 80202 USA).

Appendix D: Relation to XMPP

The Extensible Messaging and Presence Protocol (XMPP) is defined in the XMPP Core (RFC 3920) and XMPP IM (RFC 3921) specifications contributed by the XMPP Standards Foundation to the Internet Standards Process, which is managed by the Internet Engineering Task Force in accordance with RFC 2026. Any protocol defined in this document has been developed outside the Internet Standards Process and is to be understood as an extension to XMPP rather than as an evolution, development, or modification of XMPP itself.

Appendix E: Discussion Venue

There exists a special venue for discussion related to the technology described in this document: the <operators@xmpp.org> mailing list.

The primary venue for discussion of XMPP Extension Protocols is the <standards@xmpp.org> discussion list.

Discussion on other xmpp.org discussion lists might also be appropriate; see <http://xmpp.org/about/discuss.shtml> for a complete list.

Errata can be sent to <editor@xmpp.org>.

Appendix F: Requirements Conformance

The following requirements keywords as used in this document are to be interpreted as described in RFC 2119: "MUST", "SHALL", "REQUIRED"; "MUST NOT", "SHALL NOT"; "SHOULD", "RECOMMENDED"; "SHOULD NOT", "NOT RECOMMENDED"; "MAY", "OPTIONAL".

Appendix G: Notes

1. RFC 5070: The Incident Object Description Exchange Format <http://tools.ietf.org/html/rfc5070>.

2. RFC 2350: Expectations for Computer Security Incident Response <http://tools.ietf.org/html/rfc2350>.

3. RFC 3067: TERENA's Incident Object Description and Exchange Format Requirements <http://tools.ietf.org/html/rfc3067>.

4. RFC 6045: Real-time Inter-network Defense (RID) <http://tools.ietf.org/html/rfc6045>.

5. Extensible Messaging and Presence Protocol (XMPP): Address Format <https://datatracker.ietf.org/doc/draft-ietf-xmpp-6122bis/>. Work in progress.

6. XEP-0267: Server Buddies <http://xmpp.org/extensions/xep-0267.html>.

7. XEP-0205: Best Practices to Discourage Denial of Service Attacks <http://xmpp.org/extensions/xep-0205.html>.

8. The Internet Assigned Numbers Authority (IANA) is the central coordinator for the assignment of unique parameter values for Internet protocols, such as port numbers and URI schemes. For further information, see <http://www.iana.org/>.

9. The XMPP Registrar maintains a list of reserved protocol namespaces as well as registries of parameters used in the context of XMPP extension protocols approved by the XMPP Standards Foundation. For further information, see <http://xmpp.org/registrar/>.

10. XEP-0053: XMPP Registrar Function <http://xmpp.org/extensions/xep-0053.html>.

Appendix H: Revision History

Note: Older versions of this specification might be available at http://xmpp.org/extensions/attic/

Version 0.5 (2012-05-16)

Simplified the processing model to send reports only in IQ-sets (not in IQ-results); filled out the sections on inquiries, requests, and responses; corrected the schema and examples.

(psa)

Version 0.4 (2012-04-17)

Changed the XML format from a custom schema to IODEF (RFC 5070); incremented namespace version from 1 to 2.

(psa)

Version 0.3 (2009-11-17)

Added security considerations; defined schema.

(psa)

Version 0.2 (2009-06-05)

Added more detailed information about the solution element; removed the suggestion element since the solution element can be used by both reporting entities and receiving entities; added notes about processing of incident reports by receiving entities.

(mw/psa)

Version 0.1 (2009-04-30)

Initial published version.

(psa)

Version 0.0.3 (2009-04-30)

Per Council feedback, moved server rosters to a separate specification.

(psa)

Version 0.0.2 (2009-04-27)

Refactored XML format; added elements for sub-categories, locations, related incidents, solutions, and suggestions.

(psa/fj)

Version 0.0.1 (2009-04-13)

First draft.

(ah/fj/psa/mr/mw)

END