DOTS                                                   K. Nishizuka, Ed.
Internet-Draft                                        NTT Communications
Intended status: Standards Track                               T. Nagata
Expires: May 25, 2019                                            Lepidum
                                                           T. Reddy, Ed.
                                                                  McAfee
                                                            M. Boucadair
                                                                  Orange
                                                       November 21, 2018


         Controlling Filtering Rules Using DOTS Signal Channel
            draft-nishizuka-dots-signal-control-filtering-00

Abstract

   This document specifies an extension to the DOTS signal channel to
   control the filtering rules during attack mitigation.

   This extension allows a DOTS client to activate or de-activate
   filtering rules during a DDoS attack.  The characterization of these
   filters is supposed to be conveyed by a DOTS client during peace time
   by means of DOTS data channel.

Editorial Note (To be removed by RFC Editor)

   Please update these statements within the document with the RFC
   number to be assigned to this document:

   o  "This version of this YANG module is part of RFC XXXX;"

   o  "RFC XXXX: Controlling Filtering Rules Using DOTS Signal Channel";

   o  reference: RFC XXXX

   o  [RFCXXXX]

   Please update these statements with the RFC number to be assigned to
   the following documents:

   o  "RFC SSSS: Distributed Denial-of-Service Open Threat Signaling
      (DOTS) Signal Channel Specification" (used to be
      [I-D.ietf-dots-signal-channel])

   o  "RFC DDDD: Distributed Denial-of-Service Open Threat Signaling
      (DOTS) Data Channel Specification" (used to be
      [I-D.ietf-dots-data-channel])




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   Please update the "revision" date of the YANG module.

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
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   Internet-Drafts are draft documents valid for a maximum of six months
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   This Internet-Draft will expire on May 25, 2019.

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
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  The Problem . . . . . . . . . . . . . . . . . . . . . . .   3
     1.2.  The Solution  . . . . . . . . . . . . . . . . . . . . . .   4
   2.  Notational Conventions and Terminology  . . . . . . . . . . .   4
   3.  Controlling Filtering Rules . . . . . . . . . . . . . . . . .   4
     3.1.  Binding of the Data Channel and Signal Channel  . . . . .   4
     3.2.  DOTS Signal Channel Extension . . . . . . . . . . . . . .   5
       3.2.1.  Filtering Control . . . . . . . . . . . . . . . . . .   5
       3.2.2.  DOTS Signal Filtering Control Module  . . . . . . . .   6
         3.2.2.1.  Tree Structure  . . . . . . . . . . . . . . . . .   6
         3.2.2.2.  YANG Module . . . . . . . . . . . . . . . . . . .   6
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   9



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     4.1.  DOTS Signal Channel CBOR Mappings Registry  . . . . . . .   9
     4.2.  DOTS Signal Control Filtering YANG Module . . . . . . . .   9
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  10
   6.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  10
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  10
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  10
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  11
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  11

1.  Introduction

1.1.  The Problem

   The DOTS data channel protocol [I-D.ietf-dots-data-channel] is used
   for bulk data exchange between DOTS agents to improve the
   coordination of all the parties involved in the response to the DDoS
   attack.  Filter management is one of its tasks which enables a DOTS
   client to retrieve DOTS server filtering capabilities and to manage
   filtering rules.  Filtering rules are used for dropping or rate-
   limiting unwanted traffic, and permitting accept-listed traffic.

   Unlike the signal channel, the data channel is not expected to deal
   with attack conditions.  As such, an issue that might be encountered
   in some deployments is when filters installed by means of DOTS data
   channel protocol may not function as expected during DDoS attacks or
   exacerbate an ongoing DDoS attack.  The DOTS data channel cannot be
   used then to change these filters, which may complicate DDoS
   mitigation operations.

   A typical case is a DOTS client which configures during peace time
   filtering rules using data channel to permit traffic from accept-
   listed sources, but during the volumetric DDoS attack the DDoS
   mitigator identifies the source addresses/prefixes in the accept-
   listed filtering rules are attacking the target.  For example, an
   attacker can spoof the IP addresses of accept-listed sources to
   generate attack traffic or the attacker can compromise the accept-
   listed sources and program them to launch DDoS attack.

   [I-D.ietf-dots-signal-channel] is designed so that the DDoS server
   notifies the conflict to the DOTS client ('conflict-cause' set to 2
   (Conflicts with an existing accept list)), but the DOTS client may
   not be able to withdraw the accept-listed filtering rules during the
   attack period due to the high-volume attack traffic saturating the
   inbound link.  In other words, the DOTS client cannot use the DOTS
   data channel to withdraw the accept-listed filters when the DDoS
   attack is in progress.  This assumes that this DOTS client is the
   owner of the filtering rule.




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1.2.  The Solution

   This specification addresses the problems discussed in Section 1.1 by
   adding the capability of managing filtering rules using the DOTS
   signal channel, which enables a DOTS client to request the activation
   or de-activation of filtering rules during a DDoS attack.

   The DOTS signal channel protocol [I-D.ietf-dots-signal-channel] is
   designed to enable a DOTS client to contact a DOTS server for help
   even under severe network congestion conditions.  Therefore,
   extending the DOTS signal channel protocol to manage the filtering
   rules during a attack will enhance the protection capability offered
   by DOTS protocols.

      Note: The experiment at the IETF103 hackathon showed that even
      when the incoming link is saturated by DDoS attack traffic, the
      DOTS client can signal mitigation requests using the DOTS signal
      channel over the saturated link.

   Conflicts that are induced by filters installed by other DOTS clients
   of the same domain are not discussed in this specification.

2.  Notational Conventions and Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   The reader should be familiar with the terms defined in
   [I-D.ietf-dots-requirements].

3.  Controlling Filtering Rules

3.1.  Binding of the Data Channel and Signal Channel

   The filtering rules eventually managed using the DOTS signal channel
   must be created a priori by the same DOTS client using the DOTS data
   channel.  Managing conflicts with filters installed by other DOTS
   clients of the same domain is out of scope.

   As discussed in Section 4.4.1 of [I-D.ietf-dots-signal-channel], a
   DOTS client must use the same 'cuid' for both the signal and data
   channels.  This requirement is meant to facilitate binding channels
   used by the same DOTS client.





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   The DOTS signal and data channels from a DOTS client may or may not
   use the same DOTS server.  Nevertheless, the scope of the mitigation
   request, alias, and filtering rules are not restricted to the DOTS
   server but to the DOTS server administrative domain.  To that aim,
   DOTS servers within a domain are assumed to have a mechanism to
   coordinate the mitigation requests, aliases, and filtering rules to
   coordinate their decisions for better mitigation operation
   efficiency.  The exact details about such mechanism is out of scope
   of this document.

   A filtering rule controlled by the DOTS signal channel is identified
   by its Access Control List (ACL) name.  Note that an ACL name
   unambiguously identifies an ACL bound to a DOTS client, but the same
   name may be used by distinct DOTS clients.

   The activation or de-activation of an ACL by the signal channel
   overrides the 'activation-type' (defined in Section 7.2
   [I-D.ietf-dots-data-channel]) a priori conveyed with the filtering
   rules using the DOTS data channel.

3.2.  DOTS Signal Channel Extension

3.2.1.  Filtering Control

   This specification extends the mitigation request defined in
   [I-D.ietf-dots-signal-channel] to convey the intended control of the
   configured filtering rules.  The DOTS client conveys the following
   parameters in the CBOR body of the mitigation request:

   acl-name:  A name of an access list defined in the data channel.

      As a reminder, an ACL is an ordered list of Access Control Entries
      (ACE).  Each Access Control Entry has a list of match criteria and
      a list of actions.  The list of configured ACLs can be retrieved
      using the DOTS data channel during peace time.

      This is an optional attribute.

   activation-type:  Indicates the activation type of an ACL overriding
      the existing 'activation-type' installed by the DOTS data channel.
      This attribute can be set to 'deactivate', 'immediate', or
      'activate-when-mitigating' defined [I-D.ietf-dots-data-channel].
      Note that 'immediate' or 'activate-when-mitigating' are equivalent
      when a mitigation request is being processed by the server.

      If this attribute is not provided, the DOTS server MUST use
      'activate-when-mitigating' as the default value.




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      This is an optional attribute.

   If the DOTS server does not find the ACL name conveyed in the
   mitigation request in its configuration data for this DOTS client, it
   MUST respond with a "4.04 (Not Found)" error response code.

3.2.2.  DOTS Signal Filtering Control Module

3.2.2.1.  Tree Structure

   This document augments the "dots-signal-channel" DOTS signal YANG
   module defined in [I-D.ietf-dots-signal-channel] for managing the
   filtering rules.

   This document defines the YANG module "ietf-dots-signal-control-
   filter", which has the following tree structure:

   module: ietf-dots-signal-control-filter
     augment /ietf-signal:dots-signal/ietf-signal:message-type
              /ietf-signal:mitigation-scope/ietf-signal:scope:
       +--rw acl-list* [acl-name] {control-filtering}?
          +--rw acl-name
          |    -> /ietf-data:dots-data/dots-client/acls/acl/name
          +--rw activation-type?    enumeration

3.2.2.2.  YANG Module

 <CODE BEGINS> file "ietf-dots-signal-control-filter@2018-11-20.yang"

 module ietf-dots-signal-control-filter {
   yang-version 1.1;
   namespace
      "urn:ietf:params:xml:ns:yang:ietf-dots-signal-control-filter";
   prefix signal-control-filter;

   import ietf-dots-signal-channel {
     prefix ietf-signal;
     reference
       "RFC SSSS: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Signal Channel Specification";
     }
   import ietf-dots-data-channel {
     prefix ietf-data;
     reference
       "RFC DDDD: Distributed Denial-of-Service Open Threat
                  Signaling (DOTS) Data Channel Specification";
   }




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   organization
     "IETF DDoS Open Threat Signaling (DOTS) Working Group";
   contact
     "WG Web:   <https://datatracker.ietf.org/wg/dots/>
      WG List:  <mailto:dots@ietf.org>

      Author:  Konda, Tirumaleswar Reddy
               <mailto:TirumaleswarReddy_Konda@McAfee.com>;

      Author:  Kaname Nishizuka
               <mailto:kaname@nttv6.jp>;

      Author:  Takahiko Nagata
                  <mailto:nagata@lepidum.co.jp>

      Author:  Mohamed Boucadair
               <mailto:mohamed.boucadair@orange.com>;";

      description
        "This module contains YANG definition for the signaling
         messages exchanged between a DOTS client and a DOTS server
         for the DOTS signal channel controlling the filtering rules
         configured using the DOTS data channel.

         Copyright (c) 2018 IETF Trust and the persons identified as
         authors of the code.  All rights reserved.

         Redistribution and use in source and binary forms, with or
         without modification, is permitted pursuant to, and subject
         to the license terms contained in, the Simplified BSD License
         set forth in Section 4.c of the IETF Trust's Legal Provisions
         Relating to IETF Documents
         (http://trustee.ietf.org/license-info).

         This version of this YANG module is part of RFC XXXX; see
         the RFC itself for full legal notices.";

       revision 2018-11-20 {
         description
           "Initial revision.";
         reference
           "RFC XXXX: Controlling Filtering Rules Using DOTS Signal
                      Channel ";
       }

       feature control-filtering {
         description
           "This feature means that DOTS signal channel is able to



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            manage the filtering rules created by the same DOTS
            client using the DOTS data channel.";
       }

       augment "/ietf-signal:dots-signal/ietf-signal:message-type/" +
               "ietf-signal:mitigation-scope/ietf-signal:scope" {
         if-feature control-filtering;

         description "ACL name and activation type";

         list acl-list {
           key "acl-name";
           description
             "List of ACLs as defined in the DOTS data
              channel.  These ACLs are uniquely defined by
              cuid and name.";
           leaf acl-name {
             type leafref {
               path "/ietf-data:dots-data/ietf-data:dots-client/" +
                    "ietf-data:acls/ietf-data:acl/ietf-data:name";
             }
             description
               "Reference to the ACL name bound to
                a DOTS client.";
           }
           leaf activation-type {
             type enumeration {
               enum "activate-when-mitigating" {
               value 1;
               description
                 "The ACL is installed only when a mitigation is active.
                  The ACL is specific to this DOTS client.";
               }
               enum "immediate" {
                 value 2;
                 description
                   "The ACL is immediately activated.";
               }
               enum "deactivate" {
                 value 3;
                 description
                  "The ACL is maintained by the server, but it is
                   deactivated.";
               }
             }
             description
               "Set the activation type of an ACL.";
           }



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         }
       }
 }
 <CODE ENDS>

4.  IANA Considerations

4.1.  DOTS Signal Channel CBOR Mappings Registry

   This specification registers the 'activation-type' parameter in the
   IANA "DOTS Signal Channel CBOR Mappings" registry established by
   [I-D.ietf-dots-signal-channel].

   The 'activation-type' is a comprehension-required parameter.  The
   'acl-list' and 'acl-name' parameters are defined as comprehension-
   required parameters in Table 6 in [I-D.ietf-dots-signal-channel].
   Following the rules in [I-D.ietf-dots-signal-channel], if the DOTS
   server does not understand the 'acl-list' or 'acl-name' or
   'activation-type' attributes, it responds with a "4.00 (Bad Request)"
   error response code.

   o  Note to the RFC Editor: Please delete (TBD1) once the CBOR key is
      assigned from the 0x8000 - 0xBFFF range.

   +-------------------+------------+--------+---------------+--------+
   | Parameter Name    | YANG       | CBOR   | CBOR Major    | JSON   |
   |                   | Type       | Key    |    Type &     | Type   |
   |                   |            |        | Information   |        |
   +-------------------+------------+--------+---------------+--------+
   | activation-type   | enumeration| 0x0031 | 0 unsigned    | String |
   |                   |            | (TBD1) |               |        |
   +-------------------+------------+--------+---------------+--------+

4.2.  DOTS Signal Control Filtering YANG Module

   This document requests IANA to register the following URI in the
   "IETF XML Registry" [RFC3688]:

      URI: urn:ietf:params:xml:ns:yang:ietf-dots-signal-control-filter
      Registrant Contact: The IESG.
      XML: N/A; the requested URI is an XML namespace.


   This document requests IANA to register the following YANG module in
   the "YANG Module Names" registry [RFC7950].






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  name: ietf-dots-signal-control-filter
  namespace: urn:ietf:params:xml:ns:yang:ietf-dots-signal-control-filter
  prefix: signal-control-filter
  reference: RFC XXXX


5.  Security Considerations

   The security considerations discussed in
   [I-D.ietf-dots-signal-channel] and [I-D.ietf-dots-data-channel] need
   to be taken into account.

6.  Acknowledgements

   TBD

7.  References

7.1.  Normative References

   [I-D.ietf-dots-data-channel]
              Boucadair, M., K, R., Nishizuka, K., Xia, L., Patil, P.,
              Mortensen, A., and N. Teague, "Distributed Denial-of-
              Service Open Threat Signaling (DOTS) Data Channel
              Specification", draft-ietf-dots-data-channel-22 (work in
              progress), September 2018.

   [I-D.ietf-dots-signal-channel]
              K, R., Boucadair, M., Patil, P., Mortensen, A., and N.
              Teague, "Distributed Denial-of-Service Open Threat
              Signaling (DOTS) Signal Channel Specification", draft-
              ietf-dots-signal-channel-25 (work in progress), September
              2018.

   [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>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004, <https://www.rfc-
              editor.org/info/rfc3688>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.





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   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

7.2.  Informative References

   [I-D.ietf-dots-requirements]
              Mortensen, A., Moskowitz, R., and R. K, "Distributed
              Denial of Service (DDoS) Open Threat Signaling
              Requirements", draft-ietf-dots-requirements-16 (work in
              progress), October 2018.

Authors' Addresses

   Kaname Nishizuka (editor)
   NTT Communications
   GranPark 16F 3-4-1 Shibaura, Minato-ku
   Tokyo  108-8118
   Japan

   Email: kaname@nttv6.jp


   Takahiko Nagata
   Lepidum
   Japan

   Email: nagata@lepidum.co.jp


   Tirumaleswar Reddy (editor)
   McAfee, Inc.
   Embassy Golf Link Business Park
   Bangalore, Karnataka  560071
   India

   Email: kondtir@gmail.com


   Mohamed Boucadair
   Orange
   Rennes  35000
   France

   Email: mohamed.boucadair@orange.com






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