draft-ietf-hip-rfc4423-bis-01.txt   draft-ietf-hip-rfc4423-bis-02.txt 
Network Working Group R. Moskowitz Network Working Group R. Moskowitz
Internet-Draft ICSA labs Internet-Draft Verizon
Obsoletes: 4423 (if approved) August 24, 2010 Obsoletes: 4423 (if approved) February 25, 2011
Intended status: Standards Track Intended status: Standards Track
Expires: February 25, 2011 Expires: August 29, 2011
Host Identity Protocol Architecture Host Identity Protocol Architecture
draft-ietf-hip-rfc4423-bis-01 draft-ietf-hip-rfc4423-bis-02
Abstract Abstract
This memo describes a new namespace, the Host Identity namespace, and This memo describes a new namespace, the Host Identity namespace, and
a new protocol layer, the Host Identity Protocol, between the a new protocol layer, the Host Identity Protocol, between the
internetworking and transport layers. Herein are presented the internetworking and transport layers. Herein are presented the
basics of the current namespaces, their strengths and weaknesses, and basics of the current namespaces, their strengths and weaknesses, and
how a new namespace will add completeness to them. The roles of this how a new namespace will add completeness to them. The roles of this
new namespace in the protocols are defined. new namespace in the protocols are defined.
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 25, 2011. This Internet-Draft will expire on August 29, 2011.
Copyright Notice Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
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1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1. Terms common to other documents . . . . . . . . . . . . . . 5 2.1. Terms common to other documents . . . . . . . . . . . . . . 5
2.2. Terms specific to this and other HIP documents . . . . . . . 5 2.2. Terms specific to this and other HIP documents . . . . . . . 5
3. Background . . . . . . . . . . . . . . . . . . . . . . . . . 7 3. Background . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.1. A desire for a namespace for computing platforms . . . . . . 7 3.1. A desire for a namespace for computing platforms . . . . . . 7
4. Host Identity namespace . . . . . . . . . . . . . . . . . . 9 4. Host Identity namespace . . . . . . . . . . . . . . . . . . 9
4.1. Host Identifiers . . . . . . . . . . . . . . . . . . . . . . 10 4.1. Host Identifiers . . . . . . . . . . . . . . . . . . . . . . 10
4.2. Storing Host Identifiers in DNS . . . . . . . . . . . . . . 10 4.2. Storing Host Identifiers in DNS . . . . . . . . . . . . . . 10
4.3. Host Identity Tag (HIT) . . . . . . . . . . . . . . . . . . 11 4.3. Host Identity Tag (HIT) . . . . . . . . . . . . . . . . . . 11
4.4. Local Scope Identifier (LSI) . . . . . . . . . . . . . . . . 11 4.4. Host Identity Hash (HIH) . . . . . . . . . . . . . . . . . . 11
5. New stack architecture . . . . . . . . . . . . . . . . . . . 11 4.5. Local Scope Identifier (LSI) . . . . . . . . . . . . . . . . 11
5.1. Transport associations and end-points . . . . . . . . . . . 12 5. New stack architecture . . . . . . . . . . . . . . . . . . . 12
5.1. Transport associations and end-points . . . . . . . . . . . 13
6. End-host mobility and multi-homing . . . . . . . . . . . . . 13 6. End-host mobility and multi-homing . . . . . . . . . . . . . 13
6.1. Rendezvous mechanism . . . . . . . . . . . . . . . . . . . . 13 6.1. Rendezvous mechanism . . . . . . . . . . . . . . . . . . . . 14
6.2. Protection against flooding attacks . . . . . . . . . . . . 14 6.2. Protection against flooding attacks . . . . . . . . . . . . 14
7. HIP and IPsec . . . . . . . . . . . . . . . . . . . . . . . 14 7. HIP and IPsec . . . . . . . . . . . . . . . . . . . . . . . 15
8. HIP and NATs . . . . . . . . . . . . . . . . . . . . . . . . 15 8. HIP and MAC Security . . . . . . . . . . . . . . . . . . . . 16
8.1. HIP and TCP checksums . . . . . . . . . . . . . . . . . . . 16 9. HIP and NATs . . . . . . . . . . . . . . . . . . . . . . . . 16
9. Multicast . . . . . . . . . . . . . . . . . . . . . . . . . 16 9.1. HIP and Upper-layer checksums . . . . . . . . . . . . . . . 17
10. HIP policies . . . . . . . . . . . . . . . . . . . . . . . . 16 10. Multicast . . . . . . . . . . . . . . . . . . . . . . . . . 17
11. Benefits of HIP . . . . . . . . . . . . . . . . . . . . . . 17 11. HIP policies . . . . . . . . . . . . . . . . . . . . . . . . 17
11.1. HIP's answers to NSRG questions . . . . . . . . . . . . . . 18 12. Benefits of HIP . . . . . . . . . . . . . . . . . . . . . . 18
12. Changes from RFC 4423 . . . . . . . . . . . . . . . . . . . 20 12.1. HIP's answers to NSRG questions . . . . . . . . . . . . . . 19
13. Security considerations . . . . . . . . . . . . . . . . . . 20 13. Changes from RFC 4423 . . . . . . . . . . . . . . . . . . . 21
13.1. HITs used in ACLs . . . . . . . . . . . . . . . . . . . . . 21 14. Security considerations . . . . . . . . . . . . . . . . . . 21
13.2. Non-security considerations . . . . . . . . . . . . . . . . 22 14.1. HITs used in ACLs . . . . . . . . . . . . . . . . . . . . . 23
14. IANA considerations . . . . . . . . . . . . . . . . . . . . 23 14.2. Non-security considerations . . . . . . . . . . . . . . . . 23
15. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 23 15. IANA considerations . . . . . . . . . . . . . . . . . . . . 24
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 23 16. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 24
16.1. Normative References . . . . . . . . . . . . . . . . . . . . 23 17. References . . . . . . . . . . . . . . . . . . . . . . . . . 25
16.2. Informative references . . . . . . . . . . . . . . . . . . . 23 17.1. Normative References . . . . . . . . . . . . . . . . . . . . 25
Author's Address . . . . . . . . . . . . . . . . . . . . . . 25 17.2. Informative references . . . . . . . . . . . . . . . . . . . 25
Author's Address . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction 1. Introduction
The Internet has two important global namespaces: Internet Protocol The Internet has two important global namespaces: Internet Protocol
(IP) addresses and Domain Name Service (DNS) names. These two (IP) addresses and Domain Name Service (DNS) names. These two
namespaces have a set of features and abstractions that have powered namespaces have a set of features and abstractions that have powered
the Internet to what it is today. They also have a number of the Internet to what it is today. They also have a number of
weaknesses. Basically, since they are all we have, we try and do too weaknesses. Basically, since they are all we have, we try and do too
much with them. Semantic overloading and functionality extensions much with them. Semantic overloading and functionality extensions
have greatly complicated these namespaces. have greatly complicated these namespaces.
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There is a subtle but important difference between Host Identities There is a subtle but important difference between Host Identities
and Host Identifiers. An Identity refers to the abstract entity that and Host Identifiers. An Identity refers to the abstract entity that
is identified. An Identifier, on the other hand, refers to the is identified. An Identifier, on the other hand, refers to the
concrete bit pattern that is used in the identification process. concrete bit pattern that is used in the identification process.
Although the Host Identifiers could be used in many authentication Although the Host Identifiers could be used in many authentication
systems, such as IKEv2 [RFC4306], the presented architecture systems, such as IKEv2 [RFC4306], the presented architecture
introduces a new protocol, called the Host Identity Protocol (HIP), introduces a new protocol, called the Host Identity Protocol (HIP),
and a cryptographic exchange, called the HIP base exchange; see also and a cryptographic exchange, called the HIP base exchange; see also
Section 7. The HIP protocols under development provide for limited Section 7. The HIP protocols provide for limited forms of trust
forms of trust between systems, enhance mobility, multi-homing and between systems, enhance mobility, multi-homing and dynamic IP
dynamic IP renumbering, aid in protocol translation / transition, and renumbering, aid in protocol translation / transition, and reduce
reduce certain types of denial-of-service (DoS) attacks. certain types of denial-of-service (DoS) attacks.
When HIP is used, the actual payload traffic between two HIP hosts is When HIP is used, the actual payload traffic between two HIP hosts is
typically, but not necessarily, protected with IPsec. The Host typically, but not necessarily, protected with IPsec. The Host
Identities are used to create the needed IPsec Security Associations Identities are used to create the needed IPsec Security Associations
(SAs) and to authenticate the hosts. When IPsec is used, the actual (SAs) and to authenticate the hosts. When IPsec is used, the actual
payload IP packets do not differ in any way from standard IPsec payload IP packets do not differ in any way from standard IPsec
protected IP packets. protected IP packets.
Much has been learned about HIP since [RFC4423] was published. This Much has been learned about HIP since [RFC4423] was published. This
document expands Host Identities beyond use to enable IP connectivity document expands Host Identities beyond use to enable IP connectivity
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| End-point | A communicating entity. For historical reasons, | | End-point | A communicating entity. For historical reasons, |
| | the term 'computing platform' is used in this | | | the term 'computing platform' is used in this |
| | document as a (rough) synonym for end-point. | | | document as a (rough) synonym for end-point. |
+---------------+---------------------------------------------------+ +---------------+---------------------------------------------------+
2.2. Terms specific to this and other HIP documents 2.2. Terms specific to this and other HIP documents
It should be noted that many of the terms defined herein are It should be noted that many of the terms defined herein are
tautologous, self-referential or defined through circular reference tautologous, self-referential or defined through circular reference
to other terms. This is due to the succinct nature of the to other terms. This is due to the succinct nature of the
definitions. See the text elsewhere in this document for more definitions. See the text elsewhere in this document and in RFC 5201
elaborate explanations. [RFC5201-bis] for more elaborate explanations.
+---------------+---------------------------------------------------+ +---------------+---------------------------------------------------+
| Term | Explanation | | Term | Explanation |
+---------------+---------------------------------------------------+ +---------------+---------------------------------------------------+
| Computing | An entity capable of communicating and computing, | | Computing | An entity capable of communicating and computing, |
| platform | for example, a computer. See the definition of | | platform | for example, a computer. See the definition of |
| | 'End-point', above. | | | 'End-point', above. |
| | | | | |
| HIP base | A cryptographic protocol; see also Section 7. | | HIP base | A cryptographic protocol; see also Section 7. |
| exchange | | | exchange | |
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| | | | | |
| Host Identity | A name space formed by all possible Host | | Host Identity | A name space formed by all possible Host |
| namespace | Identifiers. | | namespace | Identifiers. |
| | | | | |
| Host Identity | A protocol used to carry and authenticate Host | | Host Identity | A protocol used to carry and authenticate Host |
| Protocol | Identifiers and other information. | | Protocol | Identifiers and other information. |
| | | | | |
| Host Identity | A 128-bit datum created by taking a cryptographic | | Host Identity | A 128-bit datum created by taking a cryptographic |
| Tag | hash over a Host Identifier. | | Tag | hash over a Host Identifier. |
| | | | | |
| Host Identity | The cryptograhic hash used in creating the Host |
| Hash | Identity Tag from the Host Identity. |
| | |
| Host | A public key used as a name for a Host Identity. | | Host | A public key used as a name for a Host Identity. |
| Identifier | | | Identifier | |
| | | | | |
| Local Scope | A 32-bit datum denoting a Host Identity. | | Local Scope | A 32-bit datum denoting a Host Identity. |
| Identifier | | | Identifier | |
| | | | | |
| Public Host | A published or publicly known Host Identfier used | | Public Host | A published or publicly known Host Identfier used |
| Identifier | as a public name for a Host Identity, and the | | Identifier | as a public name for a Host Identity, and the |
| and Identity | corresponding Identity. | | and Identity | corresponding Identity. |
| | | | | |
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'well known', some unpublished or 'anonymous'. A system may self- 'well known', some unpublished or 'anonymous'. A system may self-
assert its own identity, or may use a third-party authenticator like assert its own identity, or may use a third-party authenticator like
DNSSEC [RFC2535], PGP, or X.509 to 'notarize' the identity assertion. DNSSEC [RFC2535], PGP, or X.509 to 'notarize' the identity assertion.
It is expected that the Host Identifiers will initially be It is expected that the Host Identifiers will initially be
authenticated with DNSSEC and that all implementations will support authenticated with DNSSEC and that all implementations will support
DNSSEC as a minimal baseline. DNSSEC as a minimal baseline.
In theory, any name that can claim to be 'statistically globally In theory, any name that can claim to be 'statistically globally
unique' may serve as a Host Identifier. However, in the authors' unique' may serve as a Host Identifier. However, in the authors'
opinion, a public key of a 'public key pair' makes the best Host opinion, a public key of a 'public key pair' makes the best Host
Identifier. As will be specified in the Host Identity Protocol Identifier. As will be specified in the Host Identity Protocol Base
specification, a public-key-based HI can authenticate the HIP packets EXchange (BEX) [RFC5201-bis] specification, a public-key-based HI can
and protect them for man-in-the-middle attacks. Since authenticated authenticate the HIP packets and protect them for man-in-the-middle
datagrams are mandatory to provide much of HIP's denial-of-service attacks. Since authenticated datagrams are mandatory to provide much
protection, the Diffie-Hellman exchange in HIP has to be of HIP's denial-of-service protection, the Diffie-Hellman exchange in
authenticated. Thus, only public-key HI and authenticated HIP HIP BEX has to be authenticated. Thus, only public-key HI and
messages are supported in practice. In this document, the non- authenticated HIP messages are supported in practice.
cryptographic forms of HI and HIP are presented to complete the
theory of HI, but they should not be implemented as they could In this document, the non-cryptographic forms of HI and HIP are
produce worse denial-of-service attacks than the Internet has without presented to complete the theory of HI, but they should not be
Host Identity. implemented as they could produce worse denial-of-service attacks
than the Internet has without Host Identity. There is on-going
research in challenge puzzles to use non-cryptographic HI, like
RFIDs, in an HIP exchange tailored to the workings of such
challenges.
4.1. Host Identifiers 4.1. Host Identifiers
Host Identity adds two main features to Internet protocols. The Host Identity adds two main features to Internet protocols. The
first is a decoupling of the internetworking and transport layers; first is a decoupling of the internetworking and transport layers;
see Section 5. This decoupling will allow for independent evolution see Section 5. This decoupling will allow for independent evolution
of the two layers. Additionally, it can provide end-to-end services of the two layers. Additionally, it can provide end-to-end services
over multiple internetworking realms. The second feature is host over multiple internetworking realms. The second feature is host
authentication. Because the Host Identifier is a public key, this authentication. Because the Host Identifier is a public key, this
key can be used for authentication in security protocols like IPsec. key can be used for authentication in security protocols like IPsec.
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stored in various DNS or LDAP directories as identified elsewhere in stored in various DNS or LDAP directories as identified elsewhere in
this document, and they are passed in the HIP base exchange. A Host this document, and they are passed in the HIP base exchange. A Host
Identity Tag (HIT) is used in other protocols to represent the Host Identity Tag (HIT) is used in other protocols to represent the Host
Identity. Another representation of the Host Identities, the Local Identity. Another representation of the Host Identities, the Local
Scope Identifier (LSI), can also be used in protocols and APIs. Scope Identifier (LSI), can also be used in protocols and APIs.
4.2. Storing Host Identifiers in DNS 4.2. Storing Host Identifiers in DNS
The public Host Identifiers should be stored in DNS; the unpublished The public Host Identifiers should be stored in DNS; the unpublished
Host Identifiers should not be stored anywhere (besides the Host Identifiers should not be stored anywhere (besides the
communicating hosts themselves). The (public) HI is stored in a new communicating hosts themselves). The (public) HI along with the
RR type. This RR type is defined in HIP DNS Extension [RFC5205]. supported HIHs are stored in a new RR type. This RR type is defined
in HIP DNS Extension [I-D.ietf-hip-rfc5205-bis].
Alternatively, or in addition to storing Host Identifiers in the DNS, Alternatively, or in addition to storing Host Identifiers in the DNS,
they may be stored in various kinds of Public Key Infrastructure they may be stored in various kinds of Public Key Infrastructure
(PKI). Such a practice may allow them to be used for purposes other (PKI). Such a practice may allow them to be used for purposes other
than pure host identification. than pure host identification.
4.3. Host Identity Tag (HIT) 4.3. Host Identity Tag (HIT)
A Host Identity Tag is a 128-bit representation for a Host Identity. A Host Identity Tag is a 128-bit representation for a Host Identity.
It is created by taking a cryptographic hash over the corresponding It is created by taking a cryptographic hash over the corresponding
Host Identifier. There are two advantages of using a hash over using Host Identifier. There are two advantages of using a hash over using
the Host Identifier in protocols. Firstly, its fixed length makes the Host Identifier in protocols. Firstly, its fixed length makes
for easier protocol coding and also better manages the packet size for easier protocol coding and also better manages the packet size
cost of this technology. Secondly, it presents the identity in a cost of this technology. Secondly, it presents the identity in a
consistent format to the protocol independent of the cryptographic consistent format to the protocol independent of the cryptographic
algorithms used. algorithms used.
There can be multiple HITs per Host Identifier when multiple hashes
are supported. An Initator may have to initially guess which HIT to
use for the Responder, typically based on what it perfers, until it
learns the appropriate HIT through the HIP exchange.
In the HIP packets, the HITs identify the sender and recipient of a In the HIP packets, the HITs identify the sender and recipient of a
packet. Consequently, a HIT should be unique in the whole IP packet. Consequently, a HIT should be unique in the whole IP
universe as long as it is being used. In the extremely rare case of universe as long as it is being used. In the extremely rare case of
a single HIT mapping to more than one Host Identity, the Host a single HIT mapping to more than one Host Identity, the Host
Identifiers (public keys) will make the final difference. If there Identifiers (public keys) will make the final difference. If there
is more than one public key for a given node, the HIT acts as a hint is more than one public key for a given node, the HIT acts as a hint
for the correct public key to use. for the correct public key to use.
4.4. Local Scope Identifier (LSI) 4.4. Host Identity Hash (HIH)
The Host Identity Hash is the cryptographic hash used in producing
the HIT from the HI. It is also the hash used through out the HIP
protocol for consistancy and simplicity. It is possible to for the
two Hosts in the HIP exchange to use different hashes.
Multiple HIHs within HIP are needed to address the moving target of
creation and eventual compromise of cryptographic hashes. This
significantly complicates HIP and offers an attacker an additional
downgrade attack that is mitigated in the HIP protocol.
4.5. Local Scope Identifier (LSI)
An LSI is a 32-bit localized representation for a Host Identity. The An LSI is a 32-bit localized representation for a Host Identity. The
purpose of an LSI is to facilitate using Host Identities in existing purpose of an LSI is to facilitate using Host Identities in existing
protocols and APIs. LSI's advantage over HIT is its size; its protocols and APIs. LSI's advantage over HIT is its size; its
disadvantage is its local scope. disadvantage is its local scope.
Examples of how LSIs can be used include: as the address in an FTP Examples of how LSIs can be used include: as the address in an FTP
command and as the address in a socket call. Thus, LSIs act as a command and as the address in a socket call. Thus, LSIs act as a
bridge for Host Identities into IPv4-based protocols and APIs. LSIs bridge for Host Identities into IPv4-based protocols and APIs. LSIs
also make it possible for some IPv4 applications to run over an IPv6 also make it possible for some IPv4 applications to run over an IPv6
network. network.
5. New stack architecture 5. New stack architecture
One way to characterize Host Identity is to compare the proposed new One way to characterize Host Identity is to compare the proposed new
architecture with the current one. As discussed above, the IP architecture with the current one. As discussed above, the IP
addresses can be seen to be a confounding of routing direction addresses can be seen to be a confounding of routing direction
vectors and interface names. Using the terminology from the IRTF vectors and interface names. Using the terminology from the IRTF
Name Space Research Group Report [I-D.irtf-nsrg-report] and, e.g., Name Space Research Group Report [nsrg-report] and, e.g., the
the unpublished Internet-Draft Endpoints and Endpoint Names unpublished Internet-Draft Endpoints and Endpoint Names
[chiappa-endpoints], the IP addresses currently embody the dual role [chiappa-endpoints], the IP addresses currently embody the dual role
of locators and end-point identifiers. That is, each IP address of locators and end-point identifiers. That is, each IP address
names a topological location in the Internet, thereby acting as a names a topological location in the Internet, thereby acting as a
routing direction vector, or locator. At the same time, the IP routing direction vector, or locator. At the same time, the IP
address names the physical network interface currently located at the address names the physical network interface currently located at the
point-of-attachment, thereby acting as a end-point name. point-of-attachment, thereby acting as a end-point name.
In the HIP architecture, the end-point names and locators are In the HIP architecture, the end-point names and locators are
separated from each other. IP addresses continue to act as locators. separated from each other. IP addresses continue to act as locators.
The Host Identifiers take the role of end-point identifiers. It is The Host Identifiers take the role of end-point identifiers. It is
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The mobile node keeps the rendezvous infrastructure continuously The mobile node keeps the rendezvous infrastructure continuously
updated with its current IP address(es). The mobile nodes must trust updated with its current IP address(es). The mobile nodes must trust
the rendezvous mechanism to properly maintain their HIT and IP the rendezvous mechanism to properly maintain their HIT and IP
address mappings. address mappings.
The rendezvous mechanism is also needed if both of the nodes happen The rendezvous mechanism is also needed if both of the nodes happen
to change their address at the same time, either because they are to change their address at the same time, either because they are
mobile and happen to move at the same time, because one of them is mobile and happen to move at the same time, because one of them is
off-line for a while, or because of some other reason. In such a off-line for a while, or because of some other reason. In such a
case, the HIP readdress packets will cross each other in the network case, the HIP UPDATE packets will cross each other in the network and
and never reach the peer node. never reach the peer node.
The HIP rendezvous mechanism is defined in HIP Rendezvous [RFC5204]. The HIP rendezvous mechanism is defined in HIP Rendezvous
[I-D.ietf-hip-rfc5204-bis].
6.2. Protection against flooding attacks 6.2. Protection against flooding attacks
Although the idea of informing about address changes by simply Although the idea of informing about address changes by simply
sending packets with a new source address appears appealing, it is sending packets with a new source address appears appealing, it is
not secure enough. That is, even if HIP does not rely on the source not secure enough. That is, even if HIP does not rely on the source
address for anything (once the base exchange has been completed), it address for anything (once the base exchange has been completed), it
appears to be necessary to check a mobile node's reachability at the appears to be necessary to check a mobile node's reachability at the
new address before actually sending any larger amounts of traffic to new address before actually sending any larger amounts of traffic to
the new address. the new address.
Blindly accepting new addresses would potentially lead to flooding Blindly accepting new addresses would potentially lead to flooding
Denial-of-Service attacks against third parties [RFC4225]. In a Denial-of-Service attacks against third parties [RFC4225]. In a
distributed flooding attack an attacker opens high volume HIP distributed flooding attack an attacker opens high volume HIP
connections with a large number of hosts (using unpublished HIs), and connections with a large number of hosts (using unpublished HIs), and
then claims to all of these hosts that it has moved to a target then claims to all of these hosts that it has moved to a target
node's IP address. If the peer hosts were to simply accept the move, node's IP address. If the peer hosts were to simply accept the move,
the result would be a packet flood to the target node's address. To the result would be a packet flood to the target node's address. To
close this attack, HIP includes an address check mechanism where the prevent this type of attack, HIP includes an address check mechanism
reachability of a node is separately checked at each address before where the reachability of a node is separately checked at each
using the address for larger amounts of traffic. address before using the address for larger amounts of traffic.
Whenever HIP is used between two hosts that fully trust each other, A credit-based authorization approach Host Mobility with the Host
the hosts may optionally decide to skip the address tests. However, Identity Protocol [I-D.ietf-hip-rfc5206-bis] can be used between
such performance optimization must be restricted to peers that are hosts for sending data prior to completing the address tests.
known to be trustworthy and capable of protecting themselves from Otherwise, if HIP is used between two hosts that fully trust each
malicious software. other, the hosts may optionally decide to skip the address tests.
However, such performance optimization must be restricted to peers
that are known to be trustworthy and capable of protecting themselves
from malicious software.
7. HIP and IPsec 7. HIP and IPsec
The preferred way of implementing HIP is to use IPsec to carry the The preferred way of implementing HIP is to use IPsec to carry the
actual data traffic. As of today, the only completely defined method actual data traffic. As of today, the only completely defined method
is to use IPsec Encapsulated Security Payload (ESP) to carry the data is to use IPsec Encapsulated Security Payload (ESP) to carry the data
packets [RFC5202]. In the future, other ways of transporting payload packets [I-D.ietf-hip-rfc5202-bis]. In the future, other ways of
data may be developed, including ones that do not use cryptographic transporting payload data may be developed, including ones that do
protection. not use cryptographic protection.
In practice, the HIP base exchange uses the cryptographic Host In practice, the HIP base exchange uses the cryptographic Host
Identifiers to set up a pair of ESP Security Associations (SAs) to Identifiers to set up a pair of ESP Security Associations (SAs) to
enable ESP in an end-to-end manner. This is implemented in a way enable ESP in an end-to-end manner. This is implemented in a way
that can span addressing realms. that can span addressing realms.
While it would be possible, at least in theory, to use some existing While it would be possible, at least in theory, to use some existing
cryptographic protocol, such as IKEv2 together with Host Identifiers, cryptographic protocol, such as IKEv2 together with Host Identifiers,
to establish the needed SAs, HIP defines a new protocol. There are a to establish the needed SAs, HIP defines a new protocol. There are a
number of historical reasons for this, and there are also a few number of historical reasons for this, and there are also a few
architectural reasons. First, IKE (and IKEv2) were not designed with architectural reasons. First, IKE (and IKEv2) were not designed with
middle boxes in mind. As adding a new naming layer allows one to middle boxes in mind. As adding a new naming layer allows one to
potentially add a new forwarding layer (see Section 8, below), it is potentially add a new forwarding layer (see Section 9, below), it is
very important that the HIP protocols are friendly towards any middle very important that the HIP protocols are friendly towards any middle
boxes. boxes.
Second, from a conceptual point of view, the IPsec Security Parameter Second, from a conceptual point of view, the IPsec Security Parameter
Index (SPI) in ESP provides a simple compression of the HITs. This Index (SPI) in ESP provides a simple compression of the HITs. This
does require per-HIT-pair SAs (and SPIs), and a decrease of policy does require per-HIT-pair SAs (and SPIs), and a decrease of policy
granularity over other Key Management Protocols, such as IKE and granularity over other Key Management Protocols, such as IKE and
IKEv2. In particular, the current thinking is limited to a situation IKEv2. In particular, the current thinking is limited to a situation
where, conceptually, there is only one pair of SAs between any given where, conceptually, there is only one pair of SAs between any given
pair of HITs. In other words, from an architectural point of view, pair of HITs. In other words, from an architectural point of view,
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like loss of a PPP connection and its re-establishment or a mobile like loss of a PPP connection and its re-establishment or a mobile
handover will not require a HIP negotiation or disruption of handover will not require a HIP negotiation or disruption of
transport services [Bel1998]. transport services [Bel1998].
Since HIP does not negotiate any SA lifetimes, all lifetimes are Since HIP does not negotiate any SA lifetimes, all lifetimes are
local policy. The only lifetimes a HIP implementation must support local policy. The only lifetimes a HIP implementation must support
are sequence number rollover (for replay protection), and SA timeout. are sequence number rollover (for replay protection), and SA timeout.
An SA times out if no packets are received using that SA. An SA times out if no packets are received using that SA.
Implementations may support lifetimes for the various ESP transforms. Implementations may support lifetimes for the various ESP transforms.
8. HIP and NATs 8. HIP and MAC Security
The IEEE 802 standards have been defining MAC layered security. Many
of these standards use EAP [RFC3748] as a Key Management System (KMS)
transport, but some like IEEE 802.15.4 [IEEE.802-15-4.2006] leave the
KMS and its transport as "Out of Scope".
HIP is well suited as a KMS in these environments.
o HIP is independent of IP addressing and can be directly
transported over any network protocol.
o Master Keys in 802 protocols are strictly pair-based with group
keys transported from the group controller using pair-wise keys.
o AdHoc 802 networks can be better served by a peer-to-peer KMS than
the EAP client/server model.
o Some devices are very memory constrained and a common KMS for both
MAC and IP security represents a considerable code savings.
9. HIP and NATs
Passing packets between different IP addressing realms requires Passing packets between different IP addressing realms requires
changing IP addresses in the packet header. This may happen, for changing IP addresses in the packet header. This may happen, for
example, when a packet is passed between the public Internet and a example, when a packet is passed between the public Internet and a
private address space, or between IPv4 and IPv6 networks. The private address space, or between IPv4 and IPv6 networks. The
address translation is usually implemented as Network Address address translation is usually implemented as Network Address
Translation (NAT) [RFC3022] or NAT Protocol translation (NAT-PT) Translation (NAT) [RFC3022] or NAT Protocol translation (NAT-PT)
[RFC2766]. [RFC2766].
In a network environment where identification is based on the IP In a network environment where identification is based on the IP
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IP addresses. Many HITs (and SPIs) can map to a single IP address on IP addresses. Many HITs (and SPIs) can map to a single IP address on
a NAT, simplifying connections on address poor NAT interfaces. The a NAT, simplifying connections on address poor NAT interfaces. The
NAT can gain much of its knowledge from the HIP packets themselves; NAT can gain much of its knowledge from the HIP packets themselves;
however, some NAT configuration may be necessary. however, some NAT configuration may be necessary.
NAT systems cannot touch the datagrams within the IPsec envelope, NAT systems cannot touch the datagrams within the IPsec envelope,
thus application-specific address translation must be done in the end thus application-specific address translation must be done in the end
systems. HIP provides for 'Distributed NAT', and uses the HIT or the systems. HIP provides for 'Distributed NAT', and uses the HIT or the
LSI as a placeholder for embedded IP addresses. LSI as a placeholder for embedded IP addresses.
8.1. HIP and TCP checksums HIP and NAT interaction is defined in [RFC5770].
9.1. HIP and Upper-layer checksums
There is no way for a host to know if any of the IP addresses in an There is no way for a host to know if any of the IP addresses in an
IP header are the addresses used to calculate the TCP checksum. That IP header are the addresses used to calculate the TCP checksum. That
is, it is not feasible to calculate the TCP checksum using the actual is, it is not feasible to calculate the TCP checksum using the actual
IP addresses in the pseudo header; the addresses received in the IP addresses in the pseudo header; the addresses received in the
incoming packet are not necessarily the same as they were on the incoming packet are not necessarily the same as they were on the
sending host. Furthermore, it is not possible to recompute the sending host. Furthermore, it is not possible to recompute the
upper-layer checksums in the NAT/NAT-PT system, since the traffic is upper-layer checksums in the NAT/NAT-PT system, since the traffic is
IPsec protected. Consequently, the TCP and UDP checksums are IPsec protected. Consequently, the TCP and UDP checksums are
calculated using the HITs in the place of the IP addresses in the calculated using the HITs in the place of the IP addresses in the
pseudo header. Furthermore, only the IPv6 pseudo header format is pseudo header. Furthermore, only the IPv6 pseudo header format is
used. This provides for IPv4 / IPv6 protocol translation. used. This provides for IPv4 / IPv6 protocol translation.
9. Multicast 10. Multicast
There was little if any concrete thoughts about how HIP might affect Few concrete thoughts exist about how HIP might affect IP-layer or
IP-layer or application-layer multicast. application-layer multicast.
10. HIP policies 11. HIP policies
There are a number of variables that will influence the HIP exchanges There are a number of variables that will influence the HIP exchanges
that each host must support. All HIP implementations should support that each host must support. All HIP implementations should support
at least 2 HIs, one to publish in DNS and an unpublished one for at least 2 HIs, one to publish in DNS and an unpublished one for
anonymous usage. Although unpublished HIs will be rarely used as anonymous usage. Although unpublished HIs will be rarely used as
responder HIs, they are likely be common for initiators. Support for responder HIs, they are likely be common for initiators. Support for
multiple HIs is recommended. multiple HIs is recommended.
Many initiators would want to use a different HI for different Many initiators would want to use a different HI for different
responders. The implementations should provide for a policy of responders. The implementations should provide for a policy of
initiator HIT to responder HIT. This policy should also include initiator HIT to responder HIT. This policy should also include
preferred transforms and local lifetimes. preferred transforms and local lifetimes.
Responders would need a similar policy, describing the hosts allowed Responders would need a similar policy, describing the hosts allowed
to participate in HIP exchanges, and the preferred transforms and to participate in HIP exchanges, and the preferred transforms and
local lifetimes. local lifetimes.
11. Benefits of HIP 12. Benefits of HIP
In the beginning, the network layer protocol (i.e., IP) had the In the beginning, the network layer protocol (i.e., IP) had the
following four "classic" invariants: following four "classic" invariants:
o Non-mutable: The address sent is the address received. o Non-mutable: The address sent is the address received.
o Non-mobile: The address doesn't change during the course of an o Non-mobile: The address doesn't change during the course of an
"association". "association".
o Reversible: A return header can always be formed by reversing the o Reversible: A return header can always be formed by reversing the
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IP and DNS namespaces. An interesting thing about the HI is that it IP and DNS namespaces. An interesting thing about the HI is that it
actually allows one to give up all but the 3rd network-layer actually allows one to give up all but the 3rd network-layer
invariant. That is to say, as long as the source and destination invariant. That is to say, as long as the source and destination
addresses in the network-layer protocol are reversible, then things addresses in the network-layer protocol are reversible, then things
work ok because HIP takes care of host identification, and work ok because HIP takes care of host identification, and
reversibility allows one to get a packet back to one's partner host. reversibility allows one to get a packet back to one's partner host.
You do not care if the network-layer address changes in transit You do not care if the network-layer address changes in transit
(mutable) and you don't care what network-layer address the partner (mutable) and you don't care what network-layer address the partner
is using (non-omniscient). is using (non-omniscient).
11.1. HIP's answers to NSRG questions 12.1. HIP's answers to NSRG questions
The IRTF Name Space Research Group has posed a number of evaluating The IRTF Name Space Research Group has posed a number of evaluating
questions in their report [I-D.irtf-nsrg-report]. In this section, questions in their report [nsrg-report]. In this section, we provide
we provide answers to these questions. answers to these questions.
1. How would a stack name improve the overall functionality of the 1. How would a stack name improve the overall functionality of the
Internet? Internet?
HIP decouples the internetworking layer from the transport HIP decouples the internetworking layer from the transport
layer, allowing each to evolve separately. The decoupling layer, allowing each to evolve separately. The decoupling
makes end-host mobility and multi-homing easier, also across makes end-host mobility and multi-homing easier, also across
IPv4 and IPv6 networks. HIs make network renumbering easier, IPv4 and IPv6 networks. HIs make network renumbering easier,
and they also make process migration and clustered servers and they also make process migration and clustered servers
easier to implement. Furthermore, being cryptographic in easier to implement. Furthermore, being cryptographic in
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HIP provides both stable and temporary Host Identifiers. HIP provides both stable and temporary Host Identifiers.
Stable HIs are typically long lived, with a lifetime of years Stable HIs are typically long lived, with a lifetime of years
or more. The lifetime of temporary HIs depends on how long or more. The lifetime of temporary HIs depends on how long
the upper-layer connections and applications need them, and the upper-layer connections and applications need them, and
can range from a few seconds to years. can range from a few seconds to years.
4. Where does it live in the stack? 4. Where does it live in the stack?
The HIs live between the transport and internetworking layers. The HIs live between the transport and internetworking layers.
5. How is it used on the end points 5. How is it used on the end points?
The Host Identifiers may be used directly or indirectly (in The Host Identifiers may be used directly or indirectly (in
the form of HITs or LSIs) by applications when they access the form of HITs or LSIs) by applications when they access
network services. Additionally, the Host Identifiers, as network services. Additionally, the Host Identifiers, as
public keys, are used in the built in key agreement protocol, public keys, are used in the built in key agreement protocol,
called the HIP base exchange, to authenticate the hosts to called the HIP base exchange, to authenticate the hosts to
each other. each other.
6. What administrative infrastructure is needed to support it? 6. What administrative infrastructure is needed to support it?
In some environments, it is possible to use HIP In some environments, it is possible to use HIP
opportunistically, without any infrastructure. However, to opportunistically, without any infrastructure. However, to
gain full benefit from HIP, the HIs must be stored in the DNS gain full benefit from HIP, the HIs must be stored in the DNS
or a PKI, and a new rendezvous mechanism is needed[RFC5205]. or a PKI, and a new rendezvous mechanism is needed
[I-D.ietf-hip-rfc5205-bis].
7. If we add an additional layer would it make the address list in 7. If we add an additional layer would it make the address list in
SCTP unnecessary? SCTP unnecessary?
Yes Yes
8. What additional security benefits would a new naming scheme 8. What additional security benefits would a new naming scheme
offer? offer?
HIP reduces dependency on IP addresses, making the so called HIP reduces dependency on IP addresses, making the so called
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practice, HIP provides security for end-host mobility and practice, HIP provides security for end-host mobility and
multi-homing. Furthermore, since HIP Host Identifiers are multi-homing. Furthermore, since HIP Host Identifiers are
public keys, standard public key certificate infrastructures public keys, standard public key certificate infrastructures
can be applied on the top of HIP. can be applied on the top of HIP.
9. What would the resolution mechanisms be, or what characteristics 9. What would the resolution mechanisms be, or what characteristics
of a resolution mechanisms would be required? of a resolution mechanisms would be required?
For most purposes, an approach where DNS names are resolved For most purposes, an approach where DNS names are resolved
simultaneously to HIs and IP addresses is sufficient. simultaneously to HIs and IP addresses is sufficient.
However, if it becomes necessary to resolve HIs into IP However, if it becomes necessary to resolve HIs into IP
addresses or back to DNS names, a flat resolution addresses or back to DNS names, a flat resolution
infrastructure is needed. Such an infrastructure could be infrastructure is needed. Such an infrastructure could be
based on the ideas of Distributed Hash Tables, but would based on the ideas of Distributed Hash Tables, but would
require significant new development and deployment. require significant new development and deployment.
12. Changes from RFC 4423 13. Changes from RFC 4423
This section will summarize the changes made from [RFC4423]. This section summarizes the changes made from [RFC4423].
13. Security considerations 14. Security considerations
HIP takes advantage of the new Host Identity paradigm to provide HIP takes advantage of the new Host Identity paradigm to provide
secure authentication of hosts and to provide a fast key exchange for secure authentication of hosts and to provide a fast key exchange for
IPsec. HIP also attempts to limit the exposure of the host to IPsec. HIP also attempts to limit the exposure of the host to
various denial-of-service (DoS) and man-in-the-middle (MitM) attacks. various denial-of-service (DoS) and man-in-the-middle (MitM) attacks.
In so doing, HIP itself is subject to its own DoS and MitM attacks In so doing, HIP itself is subject to its own DoS and MitM attacks
that potentially could be more damaging to a host's ability to that potentially could be more damaging to a host's ability to
conduct business as usual. conduct business as usual.
Resource exhausting denial-of-service attacks take advantage of the Resource exhausting denial-of-service attacks take advantage of the
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if it has just started a connection to the responder. if it has just started a connection to the responder.
Man-in-the-middle attacks are difficult to defend against, without Man-in-the-middle attacks are difficult to defend against, without
third-party authentication. A skillful MitM could easily handle all third-party authentication. A skillful MitM could easily handle all
parts of the HIP base exchange, but HIP indirectly provides the parts of the HIP base exchange, but HIP indirectly provides the
following protection from a MitM attack. If the responder's HI is following protection from a MitM attack. If the responder's HI is
retrieved from a signed DNS zone or secured by some other means, the retrieved from a signed DNS zone or secured by some other means, the
initiator can use this to authenticate the signed HIP packets. initiator can use this to authenticate the signed HIP packets.
Likewise, if the initiator's HI is in a secure DNS zone, the Likewise, if the initiator's HI is in a secure DNS zone, the
responder can retrieve it and validate the signed HIP packets. responder can retrieve it and validate the signed HIP packets.
However, since an initiator may choose to use an unpublished HI, it However, since an initiator may choose to use an unpublished HI, it
knowingly risks a MitM attack. The responder may choose not to knowingly risks a MitM attack. The responder may choose not to
accept a HIP exchange with an initiator using an unknown HI. accept a HIP exchange with an initiator using an unknown HI.
The need to support multiple hashes for generating the HIT from the
HI affords the MitM a potentially powerful downgrade attack due to
the a-priori need of the HIT in the HIP base exchange. The base
exchange has been augmented to deal with such an attack by restarting
on detecting the attack. At worst this would only lead to a
situation in which the base exchange would never finish (or would be
aborted after some retries). As a drawback, this leads to an 6-way
base exchange which may seem bad at first. However, since this only
happens in an attack scenario and since the attack can be handled (so
it is not interesting to mount anymore), we assume the additional
messages are not a problem at all. Since the MitM cannot be
successful with a downgrade attack, these sorts of attacks will only
occur as 'nuisance' attacks. So, the base exchange would still be
usually just four packets even though implementations must be
prepared to protect themselves against the downgrade attack.
In HIP, the Security Association for IPsec is indexed by the SPI; the In HIP, the Security Association for IPsec is indexed by the SPI; the
source address is always ignored, and the destination address may be source address is always ignored, and the destination address may be
ignored as well. Therefore, HIP-enabled IPsec Encapsulated Security ignored as well. Therefore, HIP-enabled IPsec Encapsulated Security
Payload (ESP) is IP address independent. This might seem to make it Payload (ESP) is IP address independent. This might seem to make it
easier for an attacker, but ESP with replay protection is already as easier for an attacker, but ESP with replay protection is already as
well protected as possible, and the removal of the IP address as a well protected as possible, and the removal of the IP address as a
check should not increase the exposure of IPsec ESP to DoS attacks. check should not increase the exposure of IPsec ESP to DoS attacks.
Since not all hosts will ever support HIP, ICMPv4 'Destination Since not all hosts will ever support HIP, ICMPv4 'Destination
Unreachable, Protocol Unreachable' and ICMPv6 'Parameter Problem, Unreachable, Protocol Unreachable' and ICMPv6 'Parameter Problem,
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not used because it would either have to have unique content, and not used because it would either have to have unique content, and
thus difficult to generate, resulting in yet another DoS attack, or thus difficult to generate, resulting in yet another DoS attack, or
just as spoofable as the ICMP message. Like in the previous case, just as spoofable as the ICMP message. Like in the previous case,
the defense against this attack is for the initiator to wait a the defense against this attack is for the initiator to wait a
reasonable time period to get a valid HIP packet. If one does not reasonable time period to get a valid HIP packet. If one does not
come, then the initiator has to assume that the ICMP message is come, then the initiator has to assume that the ICMP message is
valid. Since this is the only point in the HIP base exchange where valid. Since this is the only point in the HIP base exchange where
this ICMP message is appropriate, it can be ignored at any other this ICMP message is appropriate, it can be ignored at any other
point in the exchange. point in the exchange.
13.1. HITs used in ACLs 14.1. HITs used in ACLs
It is expected that HITs will be used in ACLs. Future firewalls can It is expected that HITs will be used in ACLs. Future firewalls can
use HITs to control egress and ingress to networks, with an assurance use HITs to control egress and ingress to networks, with an assurance
level difficult to achieve today. As discussed above in Section 7, level difficult to achieve today. As discussed above in Section 7,
once a HIP session has been established, the SPI value in an IPsec once a HIP session has been established, the SPI value in an IPsec
packet may be used as an index, indicating the HITs. In practice, packet may be used as an index, indicating the HITs. In practice,
firewalls can inspect HIP packets to learn of the bindings between firewalls can inspect HIP packets to learn of the bindings between
HITs, SPI values, and IP addresses. They can even explicitly control HITs, SPI values, and IP addresses. They can even explicitly control
IPsec usage, dynamically opening IPsec ESP only for specific SPI IPsec usage, dynamically opening IPsec ESP only for specific SPI
values and IP addresses. The signatures in HIP packets allow a values and IP addresses. The signatures in HIP packets allow a
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HIP-aware NATs, however, are transparent to the HIP aware systems by HIP-aware NATs, however, are transparent to the HIP aware systems by
design. Thus, the host may find it difficult to notify any NAT that design. Thus, the host may find it difficult to notify any NAT that
is using a HIT in an ACL. Since most systems will know of the NATs is using a HIT in an ACL. Since most systems will know of the NATs
for their network, there should be a process by which they can notify for their network, there should be a process by which they can notify
these NATs of the change of the HIT. This is mandatory for systems these NATs of the change of the HIT. This is mandatory for systems
that function as responders behind a NAT. In a similar vein, if a that function as responders behind a NAT. In a similar vein, if a
host is notified of a change in a HIT of an initiator, it should host is notified of a change in a HIT of an initiator, it should
notify its NAT of the change. In this manner, NATs will get updated notify its NAT of the change. In this manner, NATs will get updated
with the HIT change. with the HIT change.
13.2. Non-security considerations 14.2. Non-security considerations
The definition of the Host Identifier states that the HI need not be The definition of the Host Identifier states that the HI need not be
a public key. It implies that the HI could be any value; for example a public key. It implies that the HI could be any value; for example
a FQDN. This document does not describe how to support such a non- a FQDN. This document does not describe how to support such a non-
cryptographic HI. A non-cryptographic HI would still offer the cryptographic HI. A non-cryptographic HI would still offer the
services of the HIT or LSI for NAT traversal. It would be possible services of the HIT or LSI for NAT traversal. It would be possible
to carry HITs in HIP packets that had neither privacy nor to carry HITs in HIP packets that had neither privacy nor
authentication. Since such a mode would offer so little additional authentication. Since such a mode would offer so little additional
functionality for so much addition to the IP kernel, it has not been functionality for so much addition to the IP kernel, it has not been
defined. Given how little public key cryptography HIP requires, HIP defined. Given how little public key cryptography HIP requires, HIP
should only be implemented using public key Host Identities. should only be implemented using public key Host Identities.
If it is desirable to use HIP in a low security situation where If it is desirable to use HIP in a low security situation where
public key computations are considered expensive, HIP can be used public key computations are considered expensive, HIP can be used
with very short Diffie-Hellman and Host Identity keys. Such use with very short Diffie-Hellman and Host Identity keys. Such use
makes the participating hosts vulnerable to MitM and connection makes the participating hosts vulnerable to MitM and connection
hijacking attacks. However, it does not cause flooding dangers, hijacking attacks. However, it does not cause flooding dangers,
since the address check mechanism relies on the routing system and since the address check mechanism relies on the routing system and
not on cryptographic strength. not on cryptographic strength.
14. IANA considerations 15. IANA considerations
This document has no actions for IANA. This document has no actions for IANA.
15. Acknowledgments 16. Acknowledgments
For the people historically involved in the early stages of HIP, see For the people historically involved in the early stages of HIP, see
the Acknowledgements section in the Host Identity Protocol the Acknowledgements section in the Host Identity Protocol
specification. specification.
During the later stages of this document, when the editing baton was During the later stages of this document, when the editing baton was
transfered to Pekka Nikander, the comments from the early transfered to Pekka Nikander, the comments from the early
implementors and others, including Jari Arkko, Tom Henderson, Petri implementors and others, including Jari Arkko, Tom Henderson, Petri
Jokela, Miika Komu, Mika Kousa, Andrew McGregor, Jan Melen, Tim Jokela, Miika Komu, Mika Kousa, Andrew McGregor, Jan Melen, Tim
Shepard, Jukka Ylitalo, and Jorma Wall, were invaluable. Finally, Shepard, Jukka Ylitalo, and Jorma Wall, were invaluable. Finally,
Lars Eggert, Spencer Dawkins and Dave Crocker provided valuable input Lars Eggert, Spencer Dawkins and Dave Crocker provided valuable input
during the final stages of publication, most of which was during the final stages of publication, most of which was
incorporated but some of which the authors decided to ignore in order incorporated but some of which the authors decided to ignore in order
to get this document published in the first place. to get this document published in the first place.
The authors want to express their special thanks to Tom Henderson, The authors want to express their special thanks to Tom Henderson,
who took the burden of editing the document in response to IESG who took the burden of editing the document in response to IESG
comments at the time when both of the authors were busy doing other comments at the time when both of the authors were busy doing other
things. Without his perseverance this document might have never made things. Without his perseverance original document might have never
it into an RFC form. made it as RFC4423.
16. References This latest effort to update and move HIP forward within the IETF
process owes its impetuous to the three HIP development teams:
Boeing, HIIT (Helsinki Institute for Information Technology), and
NomadicLab of Ericsson. Without their collective efforts HIP would
have withered as on the IETF vine as a nice concept.
16.1. Normative References 17. References
[RFC5202] Jokela, P., Moskowitz, R., and P. Nikander, "Using the 17.1. Normative References
Encapsulating Security Payload (ESP) Transport Format with
the Host Identity Protocol (HIP)", RFC 5202, April 2008.
[RFC5204] Laganier, J. and L. Eggert, "Host Identity Protocol (HIP) [RFC5201-bis]
Rendezvous Extension", RFC 5204, April 2008. Moskowitz, R., Jokela, P., Henderson, T., and T. Heer,
"Host Identity Protocol", draft-ietf-hip-rfc5201-bis-04
(work in progress), January 2011.
[RFC5205] Nikander, P. and J. Laganier, "Host Identity Protocol [I-D.ietf-hip-rfc5202-bis]
(HIP) Domain Name System (DNS) Extensions", RFC 5205, Jokela, P., Moskowitz, R., Nikander, P., and J. Melen,
April 2008. "Using the Encapsulating Security Payload (ESP) Transport
Format with the Host Identity Protocol (HIP)",
draft-ietf-hip-rfc5202-bis-00 (work in progress),
September 2010.
16.2. Informative references [I-D.ietf-hip-rfc5204-bis]
Laganier, J. and L. Eggert, "Host Identity Protocol (HIP)
Rendezvous Extension", draft-ietf-hip-rfc5204-bis-00 (work
in progress), August 2010.
[I-D.ietf-hip-rfc5205-bis]
Laganier, J., "Host Identity Protocol (HIP) Domain Name
System (DNS) Extension", draft-ietf-hip-rfc5205-bis-00
(work in progress), August 2010.
[I-D.ietf-hip-rfc5206-bis]
Nikander, P., Henderson, T., Vogt, C., and J. Arkko, "Host
Mobility with the Host Identity Protocol",
draft-ietf-hip-rfc5206-bis-01 (work in progress),
October 2010.
17.2. Informative references
[RFC2136] Vixie, P., Thomson, S., Rekhter, Y., and J. Bound, [RFC2136] Vixie, P., Thomson, S., Rekhter, Y., and J. Bound,
"Dynamic Updates in the Domain Name System (DNS UPDATE)", "Dynamic Updates in the Domain Name System (DNS UPDATE)",
RFC 2136, April 1997. RFC 2136, April 1997.
[RFC2535] Eastlake, D., "Domain Name System Security Extensions", [RFC2535] Eastlake, D., "Domain Name System Security Extensions",
RFC 2535, March 1999. RFC 2535, March 1999.
[RFC2766] Tsirtsis, G. and P. Srisuresh, "Network Address [RFC2766] Tsirtsis, G. and P. Srisuresh, "Network Address
Translation - Protocol Translation (NAT-PT)", RFC 2766, Translation - Protocol Translation (NAT-PT)", RFC 2766,
February 2000. February 2000.
[RFC3022] Srisuresh, P. and K. Egevang, "Traditional IP Network [RFC3022] Srisuresh, P. and K. Egevang, "Traditional IP Network
Address Translator (Traditional NAT)", RFC 3022, Address Translator (Traditional NAT)", RFC 3022,
January 2001. January 2001.
[RFC3102] Borella, M., Lo, J., Grabelsky, D., and G. Montenegro, [RFC3102] Borella, M., Lo, J., Grabelsky, D., and G. Montenegro,
"Realm Specific IP: Framework", RFC 3102, October 2001. "Realm Specific IP: Framework", RFC 3102, October 2001.
[RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J., and H.
Levkowetz, "Extensible Authentication Protocol (EAP)",
RFC 3748, June 2004.
[RFC4025] Richardson, M., "A Method for Storing IPsec Keying [RFC4025] Richardson, M., "A Method for Storing IPsec Keying
Material in DNS", RFC 4025, March 2005. Material in DNS", RFC 4025, March 2005.
[RFC4225] Nikander, P., Arkko, J., Aura, T., Montenegro, G., and E. [RFC4225] Nikander, P., Arkko, J., Aura, T., Montenegro, G., and E.
Nordmark, "Mobile IP Version 6 Route Optimization Security Nordmark, "Mobile IP Version 6 Route Optimization Security
Design Background", RFC 4225, December 2005. Design Background", RFC 4225, December 2005.
[RFC4306] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", [RFC4306] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol",
RFC 4306, December 2005. RFC 4306, December 2005.
[RFC4423] Moskowitz, R. and P. Nikander, "Host Identity Protocol [RFC4423] Moskowitz, R. and P. Nikander, "Host Identity Protocol
(HIP) Architecture", RFC 4423, May 2006. (HIP) Architecture", RFC 4423, May 2006.
[I-D.irtf-nsrg-report] [RFC5770] Komu, M., Henderson, T., Tschofenig, H., Melen, J., and A.
Keranen, "Basic Host Identity Protocol (HIP) Extensions
for Traversal of Network Address Translators", RFC 5770,
April 2010.
[nsrg-report]
Lear, E. and R. Droms, "What's In A Name:Thoughts from the Lear, E. and R. Droms, "What's In A Name:Thoughts from the
NSRG", draft-irtf-nsrg-report-10 (work in progress), NSRG", draft-irtf-nsrg-report-10 (work in progress),
September 2003. September 2003.
[IEEE.802-15-4.2006]
"Information technology - Telecommunications and
information exchange between systems - Local and
metropolitan area networks - Specific requirements - Part
15.4: Wireless Medium Access Control (MAC) and Physical
Layer (PHY) Specifications for Low-Rate Wireless Personal
Area Networks (WPANs)", IEEE Standard 802.15.4,
September 2006, <http://standards.ieee.org/getieee802/
download/802.15.4-2006.pdf>.
[chiappa-endpoints] [chiappa-endpoints]
Chiappa, J., "Endpoints and Endpoint Names: A Proposed Chiappa, J., "Endpoints and Endpoint Names: A Proposed
Enhancement to the Internet Architecture", Enhancement to the Internet Architecture",
URL http://www.chiappa.net/~jnc/tech/endpoints.txt, 1999. URL http://www.chiappa.net/~jnc/tech/endpoints.txt, 1999.
[Nik2001] Nikander, P., "Denial-of-Service, Address Ownership, and [Nik2001] Nikander, P., "Denial-of-Service, Address Ownership, and
Early Authentication in the IPv6 World", in Proceesings Early Authentication in the IPv6 World", in Proceesings
of Security Protocols, 9th International Workshop, of Security Protocols, 9th International Workshop,
Cambridge, UK, April 25-27 2001, LNCS 2467, pp. 12-26, Cambridge, UK, April 25-27 2001, LNCS 2467, pp. 12-26,
Springer, 2002. Springer, 2002.
[Bel1998] Bellovin, S., "EIDs, IPsec, and HostNAT", in Proceedings [Bel1998] Bellovin, S., "EIDs, IPsec, and HostNAT", in Proceedings
of 41th IETF, Los Angeles, CA, of 41th IETF, Los Angeles, CA,
URL http://www1.cs.columbia.edu/~smb/talks/hostnat.pdf, URL http://www1.cs.columbia.edu/~smb/talks/hostnat.pdf,
March 1998. March 1998.
Author's Address Author's Address
Robert Moskowitz Robert Moskowitz
ICSA labs, An Independent Division of Verizon Business Verizon Telcom and Business
1000 Bent Creek Blvd, Suite 200 1000 Bent Creek Blvd, Suite 200
Mechanicsburg, PA Mechanicsburg, PA
USA USA
Email: robert.moskowitz@icsalabs.com Email: robert.moskowitz@verizonbusiness.com
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