A Simple Secure Addressing Generation Scheme for IPv6 AutoConfiguration (SSAS)

Abstract

   The default method for IPv6 address generation uses two unique
   manufacturer IDs that are assigned by the IEEE Standards Association
   [1] (section 2.5.1 RFC-4291) [RFC4291]. This means that a node will
   always have the same Interface ID (IID) whenever it connects to a new
   network. Because the node's IP address does not change, the node is
   vulnerable to privacy related attacks. To address this issue, there
   are currently two mechanisms in use to randomize the IID,
   Cryptographically Generated Addresses (CGA) [RFC3972] and Privacy
   Extension [RFC4941]. The problem with the former approach is the
   computational cost involved for the IID generation. The problem with
   the latter approach is that it lacks security. This document offers a
   new algorithm for use in the generation of the IID while, at the same
   time, securing the node against some types of attack, such as IP
   spoofing. These attacks are prevented with the addition of a
   signature to the Neighbor Discovery messages (NDP).




1.  Introduction

   IPv6 addresses consist of two parts; the subnet prefix, which is the
   64 leftmost bits of the IPv6 address, and the Interface ID (IID),
   which is the 64 rightmost bits of IPv6 address. The IEEE Standards
   Association [1] (section 2.5.1 RFC-4291) [RFC4291] offered a standard
   for the generation of the IPv6 Interface IDs (IID). They are
   generated by the concatenation of an Extended Unique Identifier
   (EUI-64) with an Organizationally Unique Identifier (OUI), both of
   which are assigned by the IEEE Registration Authority (IEEE RA). For
   example, if a manufacturer's OUI-36 hexadecimal value is
   00-5A-D1-02-3, and the manufacture hexadecimal value for the
   extension identifier for a given component is 4-42-61-71, then the
   EUI-64 value generated from these two numbers will be
   00-5A-D1-02-34-42-61-71. There are two mechanisms used to randomize
   the IID; CGA [RFC3972] and Privacy Extension [RFC4941]. In this
   document we discuss the problem inherent with using the current
   mechanisms and then we propose our solution to the problem which is
   to randomize the IID, while, at the same time, providing security to
   Neighbor Discovery Protocol (NDP) messages.