Source Address Validation Improvement (SAVI) Threat Scope
RFC 6959

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 05
• 06
• 07
• 08

Internet Engineering Task Force (IETF)                      D. McPherson
Request for Comments: 6959                                VeriSign, Inc.
Category: Informational                                         F. Baker
ISSN: 2070-1721                                            Cisco Systems
                                                              J. Halpern
                                                                Ericsson
                                                                May 2013

       Source Address Validation Improvement (SAVI) Threat Scope

Abstract

   The Source Address Validation Improvement (SAVI) effort aims to
   complement ingress filtering with finer-grained, standardized IP
   source address validation.  This document describes threats enabled
   by IP source address spoofing both in the global and finer-grained
   context, describes currently available solutions and challenges, and
   provides a starting point analysis for finer-grained (host
   granularity) anti-spoofing work.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Not all documents
   approved by the IESG are a candidate for any level of Internet
   Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6959.

McPherson, et al.             Informational                     [Page 1]
RFC 6959                    SAVI Threat Scope                   May 2013

Copyright Notice

   Copyright (c) 2013 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. Overview ........................................................3
   2. Glossary of Terms ...............................................5
   3. Spoof-Based Attack Vectors ......................................6
      3.1. Blind Attacks ..............................................6
           3.1.1. Single-Packet Attacks ...............................6
           3.1.2. Flood-Based DoS .....................................7
           3.1.3. Poisoning Attacks ...................................8
           3.1.4. Spoof-Based Worm/Malware Propagation ................8
           3.1.5. Reflective Attacks ..................................8
           3.1.6. Accounting Subversion ...............................9
           3.1.7. Other Blind Spoofing Attacks ........................9
      3.2. Non-blind Attacks ..........................................9
           3.2.1. Man in the Middle (MITM) ............................9
           3.2.2. Third-Party Recon ..................................10
           3.2.3. Other Non-blind Spoofing Attacks ...................10
   4. Current Anti-spoofing Solutions ................................11
      4.1. Topological Locations for Enforcement .....................13
           4.1.1. Host to Link-Layer Neighbor via Switch .............13
           4.1.2. Upstream Switches ..................................13
           4.1.3. Upstream Routers ...................................14
           4.1.4. ISP Edge PE Router .................................14
           4.1.5. ISP NNI Router to ISP NNI Router ...................15
           4.1.6. Cable Modem Subscriber Access ......................15
           4.1.7. DSL Subscriber Access ..............................15
      4.2. Currently Available Tools .................................16
           4.2.1. BCP 38 .............................................16
           4.2.2. Unicast RPF ........................................16
           4.2.3. Port-Based Address Binding .........................16
           4.2.4. Cryptographic Techniques ...........................17
           4.2.5. Residual Attacks ...................................18

McPherson, et al.             Informational                     [Page 2]
RFC 6959                    SAVI Threat Scope                   May 2013

   5. Topological Challenges Facing SAVI .............................18