Network Working Group P. Nikander
Internet-Draft Ericsson Research Nomadic Lab
Expires: October 30, 2004 J. Laganier
LIP / Sun Microsystems
May 2004
Host Identity Protocol (HIP) Domain Name System (DNS) Extensions
draft-nikander-hip-dns-00
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Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract
This document specifies two new resource records for the Domain Name
System, and how to use them with the Host Identity Protocol. These
records allow a HIP node to store in the DNS its Host Identity (i.e.,
its public key), Host Identity Tag (i.e., a truncated hash of its
public key), and Rendezvous Servers (RVS).
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions used in this document . . . . . . . . . . . . . . 5
3. Usage scenarios . . . . . . . . . . . . . . . . . . . . . . . 6
3.1 Simple static singly homed end-host . . . . . . . . . . . 7
3.2 Mobile end-host . . . . . . . . . . . . . . . . . . . . . 7
3.3 Multi-homed end-host . . . . . . . . . . . . . . . . . . . 7
3.4 Multi-homed site . . . . . . . . . . . . . . . . . . . . . 7
3.5 Site with a HAA . . . . . . . . . . . . . . . . . . . . . 7
4. Overview of using the DNS with HIP . . . . . . . . . . . . . . 8
4.1 Different types of HITs . . . . . . . . . . . . . . . . . 8
4.1.1 Host Assigning Authority (HAA) field . . . . . . . . . 8
4.1.2 Reverse lookup based on Type 2 (HAA-based) HITs . . . 9
4.2 Storing HI and HIT in DNS . . . . . . . . . . . . . . . . 9
4.3 Storing HAA in DNS . . . . . . . . . . . . . . . . . . . . 9
4.4 Providing multiple IP addresses . . . . . . . . . . . . . 9
4.4.1 Storing Rendezvous Servers in the DNS . . . . . . . . 10
4.5 Initiating connections based on DNS names . . . . . . . . 10
4.6 Address verification . . . . . . . . . . . . . . . . . . . 10
5. Storage Format . . . . . . . . . . . . . . . . . . . . . . . . 11
5.1 HIPHI RDATA format . . . . . . . . . . . . . . . . . . . . 11
5.1.1 RDATA format HIT type . . . . . . . . . . . . . . . . 11
5.1.2 RDATA format algorithm type . . . . . . . . . . . . . 11
5.1.3 RDATA format HIT . . . . . . . . . . . . . . . . . . . 11
5.1.4 RDATA format public key . . . . . . . . . . . . . . . 12
5.2 HIPRVS RDATA format . . . . . . . . . . . . . . . . . . . 12
5.2.1 RDATA format precedence . . . . . . . . . . . . . . . 13
5.2.2 RDATA format Rendezvous server type . . . . . . . . . 13
5.2.3 RDATA format Rendezvous server . . . . . . . . . . . . 13
6. Policy considerations . . . . . . . . . . . . . . . . . . . . 14
7. Conjunction of multiple HIs with mutiple IPs . . . . . . . . . 15
8. Security Considerations . . . . . . . . . . . . . . . . . . . 16
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 18
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
11.1 Normative references . . . . . . . . . . . . . . . . . . . . 19
11.2 Informative references . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 20
Intellectual Property and Copyright Statements . . . . . . . . 21
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1. Introduction
This document specifies two new resource records (RRs) for the Domain
Name System (DNS) [8], and how to use them with the Host Identity
Protocol (HIP) [10]. These records allow a HIP node to store in the
DNS its Host Identity (i.e., its public key), Host Identity Tag
(i.e., a truncated hash of its public key), and Rendezvous Servers
(RVS) [13].
The current Internet architecture defines two global namespaces: IP
addresses and domain names. The Domain Name System provides a two way
lookup between these two namespaces.
The HIP architecture [11] defines a new third namespace called Host
Identity Namespace. This namespace is composed of the Host Identity
(HI) of HIP nodes. The Host Identity Tag (HIT) is one local
representation of a HI (the others being the IPv4-compatible and
IPv6-compatible Local Scope Identifiers - LSIs). This local
representation is obtained by taking the output of a secure hash
function applied to the HI, truncated to the IPv6 address size. HITs
are supposed to be used instead of IP addresses in some ULPs and
applications.
The Host Identity Protocol [10] allows two HIP nodes to establish a
pair of unidirectional IPsec Security Association. These SAs are
bound to HI instead of regular IP addresses.
The proposed HIP multi-homing mechanisms [12] allow a node to
dynamically change its set of underlying IP addresses while
maintaining transport layer session survivability.
The HIP rendezvous extensions [13] proposal allows a HIP node to
maintain HIP reachability while not relying on dynamic DNS updates to
make its peers aware of its current location (i.e., its set of IP
address(es)).
Although a HIP node can initiate a HIP communication
"opportunistically" (i.e., without a priori knowledge of its peer's
HI), doing so expose both endpoints to Man-in-the-Middle attacks on
the HIP handshake. Hence, there is a desire to gain knowledge of
peers' HI before applications and ULPs initiate communication.
Currently, most of the Internet applications which need to
communicate with a remote host first translate a domain name (often
obtained via user input) into one or more IP address(es). This step
occurs prior to communication with the remote host, and relies on a
DNS lookup.
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With HIP, IP addresses are expected to be used mostly for on-the-wire
communication between end hosts, while most ULPs and applications
uses HIs or HITs instead (ICMP might be an example of an ULP not
using them). Consequently, we need a means to translate a domain name
into an HI. Using the DNS for this translation is pretty
straightforward: We define a new HIPHI (HIP HI) resource record. Upon
query by an application or ULP for a FQDN -> IP lookup, the resolver
would then additionaly perform an FQDN -> HI lookup, and use it to
construct the resulting HI -> IP mapping (which is internal to the
HIP layer). The HIP layer uses the HI -> IP mapping to translate HIs
and their local representations (HITs, IPv4 and IPv6-compatible LSIs)
into IP addresses and vice versa.
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2. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC2119 [2].
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3. Usage scenarios
In this section we briefly introduce a number of usage scenarios
where the DNS is useful with the Host Identity Protocol.
With HIP, most application and ULPs are unaware of the IP addresses
used to carry packets on the wire. Consequently, a HIP node could
take advantage of having multiple IP addresses for fail-over,
redundancy, mobility or renumbering, in a manner which is transparent
to most ULPs and applications (because they are bound to HIs, hence
they are agnostic to these IP address(es) changes).
In these situations, a node wishing to be reachable by reference to
its FQDN MAY store the following informations in the DNS:
o Its set of IP address(es).
o Its Host Identity (HI) and/or Host Identity Tag (HIT).
o Its Host Assigning Authority (HAA).
o The IP address(es) or DNS name(s) of its Rendezvous Server(s)
(RVS).
When a HIP node wants to initiate a communication with another HIP
node, it first needs to perform a HIP base exchange to set-up a HIP
association towards its peer. Although such an exchange can be
initiated opportunistically, i.e., without a priori knowledge of the
responder's HI, by doing so both nodes knowingly risk
man-in-the-middle attacks on the HIP exchange. To prevent these
attacks, it is recommended that the initiator first obtain the HI of
the responder, and then initiate the exchange. This can be done
through manual configuration, or DNS lookups, hence the introduction
of the new HIPHI RR.
When a HIP node is frequently changing its IP address(es), the
dynamic DNS update latency may prevent it from publishing globally
its new IP address(es). For solving this problem, the HIP
architecture introduce Rendezvous Servers (RVS). A HIP responder uses
a Rendezvous Server as a Rendezvous point, to maintain reachability
with possible HIP initiators. Such a HIP node would publish in the
DNS its RVS' IP address or DNS name in a HIPRVS RR, while keeping its
RVS up-to-date with its current set of IP addresses.
Then, when some HIP node wants to initiate an HIP exchange with such
a responder, it retrieves its RVS IP address by looking up a HIPRVS
RR at the FQDN of the responder, and sends an I1 to this IP address.
The I1 will then be relayed by the RVS to the responder, which will
then complete the HIP exchange, either directly or via the RVS [13].
Note that storing HIP RR informations in the DNS at a FQDN which is
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assigned to a non-HIP node might have very bad effects on its
reachability by HIP nodes.
3.1 Simple static singly homed end-host
A HIP node having a single static network attachment, wishing to be
reachable by reference to its FQDN, would store in the DNS, in
addition to its IP address(es), its Host Identity (HI) in a HIPHI
resource record.
3.2 Mobile end-host
A mobile HIP node wishing to be reachable by reference to its FQDN
would store in the DNS, instead of its IP address(es), its HI in a
HIPHI RR, and the IP address(es) of its Rendezvous Server(s) in
HIPRVS resource record(s). The mobile HIP node also need to notify
its Rendezvous Servers of any change in its set of IP address(es).
A host wanting to reach this mobile host would then send an I1 to one
of its RVS. Following, the RVS will relay the I1 up to the mobile
node, which will complete the HIP exchange.
3.3 Multi-homed end-host
A HIP node having several distinct network attachments is
multi-homed. Such a HIP node might also be reachable via several
distinct Rendezvous Servers. In addition to its set of IP
address(es), a multi-homed end-host would store in the DNS its HI in
a HIPHI RR, and possibly the IP address(es) of its RVS(s) in HIPRVS
RRs.
3.4 Multi-homed site
A HIP node being attached to the network of a multi-homed site will
possibly have multiple prefixes and addresses. This site might also
be reachable via several distinct Rendezvous Servers. In addition to
its set of IP address(es), a multi-homed end-host would store in the
DNS its HI in a HIPHI RR, and possibly the IP address(es) of its site
RVS(s) in HIPRVS RRs.
3.5 Site with a HAA
A site which has an assigned HAA might store this HAA in a HIPHI RR.
This might be useful to verify that a HIP node with a given "Type 2"
HIT belongs to a site referenced by a given HAA.
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4. Overview of using the DNS with HIP
4.1 Different types of HITs
There are _currently_ two types of HITs. HITs of the first type
consists just of the SHA-1 hash of the public key. HITs of the second
type consist of a 63 bits Host Assigning Authority (HAA) field, and
only the last 64 bits come from a SHA-1 hash of the Host Identity.
This latter format for HIT is recommended for 'well known' systems.
It is possible to support a resolution mechanism for these names in
directories like DNS. Another use of HAA is in policy controls, see
Section 6.
The first bit of a HIT is used to differentiate between Type 1 and
Type 2 format. If the first bit is 0 then the rest of a HIT is the
127 upper bits of a SHA-1 hash of the Host Identity. If the first bit
is 1 then the next 63 bits is the HAA field, and only the last 64
bits come from the hash of the Host Identity.
Additionnaly, this document defines an internal IPv6-compatible LSI
representation format, to be used within the legacy IPv6-compatible
API (e.g., socket over AF_INET6). The format of these IPv6-compatible
LSIs is designed to avoid the most commonly occurring IPv6 addresses
in RFC3596 [9]. An IPv6-compatible LSI representation is easily
computed by replacing in the corresponding HIT the Bit 1 with NOT(Bit
0). That way if Bit 0 is zero and Bit 1 is one, then the rest of the
LSI is a 126 bits of a SHA-1 hash of the Host Identity. If Bit 0 is
one and Bit 1 is zero, then the next 62 bits come from the HAA field,
and only the last 64 bits come from the hash of the Host Identity.
The figure belows shows how the specified IPv6-compatible LSI format
tries to avoid collision:
Allocation Prefix Fraction of IPv6
(binary) Address Space
------------------------ -------- -------------
IPv6 Address space 00 1/4
Type 1 IPv6-compatible LSI 01 1/4
Type 2 IPv6-compatible LSI 10 1/4
IPv6 Address space 11 1/4
4.1.1 Host Assigning Authority (HAA) field
The 63 bits of HAA supports two levels of delegation. The first is a
registered assigning authority (RAA). The second is a registered
identity (RI, commonly a company). The RAA is 23 bits with values
assign sequentially by ICANN. The RI is 40 bits, also assigned
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sequentially but by the RAA.
As IPv6 "global site-local" addresses were proposed in the IPv6 WG to
replace IPv6 site-local address, it is questionable if HIP needs a
kind of "global site-local" HAA, which would be generated by a given
site by setting the RAA field to 0 while the RI field is filled by
either random or EUI-48 bits.
4.1.2 Reverse lookup based on Type 2 (HAA-based) HITs
This can be used to create a resolution mechanism in the DNS. For
example if FOO is RAA number 100 and BAR is FOO's 50th registered
identity, and if 1385D17FC63961F5 is the hash of the Host Identity
for www.bar.com, then by using DNS Binary Labels [5] there could be a
reverse lookup record like:
\[x1385D17FC63961F5/64].\[x32/40].\[x64/23].HIT.int IN PTR
www.bar.com.
(Note that RFC2673 [5] is Experimental, and that there are some bad
experiences with binary DNS labels. [7])
4.2 Storing HI and HIT in DNS
Any conforming implementation might store Host Identifiers in a DNS
HIPHI RDATA format. An implementation may also store a HIT along with
its associated HI. If a particular form of a HI or HIT does not
already have a specified RDATA format, a new RDATA-like format SHOULD
be defined for the HI or HIT.
During a transition period, instead of storing the HI or HIT in a
HIPHI RR, the HIT MAY be stored in an AAAA RR. If a HIT is stored in
an AAAA RR, it MUST be returned as the last item in the set of AAAA
RRs returned to avoid as most as possible conflicts with non-HIP IPv6
nodes.
4.3 Storing HAA in DNS
Any conforming implementation might store a site's Host Assigning
Authority in a DNS HIPHI RDATA format. A HAA MUST be stored similarly
to a Type 2 HIT, while the least significant 64-bit are set to 0. If
a particular form of a HAA does not already have an associated HIT
specified RDATA format, a new RDATA-like format SHOULD be defined for
the HIT/HAA.
4.4 Providing multiple IP addresses
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4.4.1 Storing Rendezvous Servers in the DNS
The Rendezvous server (RVS) resource record indicates an address (or
a FQDN resolvable into an address) towards which a HIP I1 packet
might be sent to trigger the establishment of an association with the
entity named by this resource record.
An RVS receiving such an I1 would then forward it to the appropriate
responder (i.e., the owner of the destination HIT in this I1). The
responder will then complete the exchange with the initiator,
possibly without ongoing help from the RVS.
Any conforming implementation may store Rendezvous Server's IP
address(es) or DNS name in a DNS HIPRVS RDATA format. If a particular
form of a RVS reference does not already have a specified RDATA
format, a new RDATA-like format SHOULD be defined for the RVS.
During a transition period, similarly to what may happen with HITs,
the RVS's IP address might be stored in an A or AAAA RR instead of a
HIPRVS RR. If a RVS IP address is stored in an A or AAAA RR, it MUST
be returned as the last item in the set of returned RRs to avoid as
most as possible conflicts with non-HIP IPv6 nodes.
4.5 Initiating connections based on DNS names
A Host Identity Protocol exchange SHOULD be initiated whenever the
DNS lookup returns HIPHI resource records. Furthermore, if the DNS
lookups also returns HIPRVS resource records, the addresses of these
RVS SHOULD be put in the destination IP addresses list while
initiating the afore mentioned HIP exchange. Since some hosts may
choose not to have HIPHI information in DNS, hosts MAY implement
support opportunistic HIP.
4.6 Address verification
Upon return of an HIPHI RR, a host MUST always calculate the
HI-derivative HIT to be used in the HIP exchange, as specified in the
HIP architecture [11], while the HIT possibly embedded along SHOULD
only be used as an optimisation (e.g., table lookup).
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5. Storage Format
5.1 HIPHI RDATA format
The RDATA for a HIPHI RR consists of a HIT type, an algorithm type, a
HIT and a public key.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| HIT type | algorithm | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ HIT |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| /
/ public key /
/ /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-|
5.1.1 RDATA format HIT type
The algorithm type indicates the Host Identity Tag (HIT) type and the
implied HIT format.
The following values are defined:
0 No HIT is present.
1 A 128-bit Type 1 HIT is present.
2 A 128-bit Type 2 HIT is present.
3 A 128-bit HAA is present.
5.1.2 RDATA format algorithm type
The algorithm type indicates the public key cryptographic algorithm
and the implied public key field format.
The following values are defined:
0 No key is present.
1 A DSA key is present, in the format defined in RFC2536 [4].
2 A RSA key is present, in the format defined in RFC3110 [6].
5.1.3 RDATA format HIT
There's currently two types of HITs, both 128-bit long, and a single
type of HAA. Both of them are stored within a a single RDATA format.
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This Field contain either:
o A *Type 1* HIT: binary prefix 0 concatenated with least
significant 127-bit of the hash (e.g., SHA1) of the public key
(Host Identity), which is possibly following in the HIPHI RR.
o A *Type 2* HIT: binary prefix 1 concatenated with a 63-bit HAA,
and the least significant 64-bit of the hash (e.g., SHA1) of the
public key (Host Identity), which is possibly following in the
HIPHI RR.
o A HAA: binary prefix 1 concatenated with a 63-bit HAA, and the
remaining 64-bit are set to 0.
5.1.4 RDATA format public key
Both of the public key types defined in this document (RSA and DSA)
inherit their public key formats from the corresponding KEY RR
formats. The public key field contains the algorithm-specific portion
of the KEY RR RDATA (i.e., all of the KEY RR DATA after the first
four octets, corresponding to the same portion of the KEY RR that
must be specified by documents that define a DNSSEC algorithm).
In the future, if a new algorithm is to be used both by DNSSEC's KEY
RR and HIPHI RR, it would probably use the same public key encodings
for both RRs. Unless specified otherwise, the HIPHI public key field
would contain the algorithm-specific portion of the KEY RR RDATA for
the corresponding algorithm. Such an algorithm must still be
designated for use with the HIP protocol and an algorithm type number
must be assigned to it. Similarly to what happened with public key
encodings, this algorithm type number is likely to be the same than
the one used in DNSSEC, though it might not always be the case.
The DSA key format is defined in RFC2536 [4].
The RSA key format is defined in RFC3110 [6].
5.2 HIPRVS RDATA format
The RDATA for a HIPRVS RR consists of a preference value, a
Rendezvous server type and a Rendezvous server address.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| preference | type | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Rendezvous server |
~ ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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5.2.1 RDATA format precedence
This is an 8-bit preference order for this record. This used to
specify the preference given to this RR amongst others at the same
owner. Lower values are preferred, and if there is a tie with some
RRs, the order should be non-deterministic (e.g., round-robin).
5.2.2 RDATA format Rendezvous server type
The Rendezvous server type indicates the format of the information
stored in the Rendezvous server field.
The following values are defined:
0 Reserved.
1 A 4-byte IPv4 address in network byte order is present.
2 A 16-byte IPv6 address in network byte order is present.
3 A variable length wire-encoded domain name as described in
section 3.3 of RFC1035 [1]. The domain name MUST NOT be
compressed.
5.2.3 RDATA format Rendezvous server
The Rendezvous server field indicates an address (or a FQDN
resolvable into an address) towards which a HIP I1 packet might be
send in order to reach the entity named by this resource record.
There are three different formats for the data portion of the
Rendezvous server field:
o A 32-bit IPv4 address in network byte order.
o A 128-bit IPv6 address in network byte order.
o A variable length wire-encoded domain name as described in section
3.3 of RFC1035 [1]. The domain name MUST NOT be compressed.
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6. Policy considerations
There are a number of variables that will influence the HIP exchanges
that each host must support. All HIP implementations MUST support at
least 2 HIs, one to publish in the DNS and one for anonymous usage.
Although anonymous HIs will be rarely used as responder HIs, they
will be common for initiators. Support for multiple HIs is
RECOMMENDED.
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7. Conjunction of multiple HIs with mutiple IPs
The RRs defined in this document are "flat", in the sense that the IP
addresses and HIs are associated to an FQDN on an equality basis. In
the case where an FQDN is resolved into multiple HIs (HIPHI RRs) and
IP addresses (A, AAAA or HIPRVS RRs), the requester cannot associate
an IP address with a specific HI, nor the opposite.
Considering the following DNS-IP load balancing model: Multiple
initiators are querying a DNS server with A or AAAA RRs at a given
FQDN. The DNS server replies with a round-robin ordered set of IP
addresses, causing each initiator to connect to a different address
(the first address of the set they received from the DNS). This model
can be extended to HIP by having the DNS returning a round-robin
ordered set of HIs, and IP addresses. But then the problem is that
the initiator would need to map each of these HIs to a subset of the
returned set of IP addresses. Hence, perhaps there is a need for
having a "hierarchical" model for these RRs, which will allows to tie
an HI to a specific subset of IP addresses, as illustrated in the
figure below:
FQDN FQDN
| / \
+-----+-----+-----+ HI1 HI2
/ / \ \ \ / \ \
IP1 IP2 IP3 HI1 HI2 IP1 IP2 IP3
"Flat" model Vs. "Hierarchical" model
However, as HIs and Type 1 HITs are not yet resolvable using the DNS,
implementing such a model would certainly prove to be difficult. The
use of Distributed Hash Tables (DHTs) might help to resolve HIs, but
at this point the whole story isn't known. In the absence of HI
resolvability, a solution might be to index each IP addresses and HIs
with a descriptor. This descriptor might be the HIT, or more
efficiently, an additional 8-bit field. That way each HIPHI, HIPRVS,
and HIPLOC (a new to-be-defined RR carrying the IP address of a HIP
node) would contain an additionnal HI index field allowing to link a
HI with a subset of IP addresses and vice versa.
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8. Security Considerations
The security considerations of the HIP DNS extensions still need to
be investigated and documented.
Man-in-the-middle attacks are difficult to defend against, without
third-party authentication. A skillful MitM could easily handle all
parts of HIP; but HIP indirectly provides the following protection
from a MitM attack. If the responder's HI is retrieved from a signed
DNS zone by the initiator, the initiator can use this to validate the
R1 HIP packet.
Likewise, if the initiator's HI is in a secure DNS zone, the
responder can retrieve it after it gets the I2 HIP packet and
validate that. However, since an initiator may choose to use an
anonymous HI, it knowingly risks a MitM attack. The responder may
choose not to accept a HIP exchange with an anonymous initiator.
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9. IANA Considerations
IANA needs to allocate two new RR type code for HIPHI and HIPRVS from
the standard RR type space.
IANA needs to open a new registry for the HIPHI RR type for public
key algorithms. Defined types are:
0 is reserved
1 is RSA
2 is DSA
Adding new reservations requires IETF consensus RFC2434 [1].
IANA needs to open a new registry for the HIPHI RR HIT type. Defined
types are:
0 No HIT is present
1 A 128-bit Type 1 HIT is present
2 A 128-bit Type 2 HIT is present
3 A 128-bit HAA is present
Adding new reservations requires IETF consensus RFC2434 [1].
IANA needs to open a new registry for the HIPRVS RR Rendezvous server
type. Defined types are:
0 is reserved
1 is IPv4
2 is IPv6
3 is a wire-encoded uncompressed domain name
Adding new reservations requires IETF consensus RFC2434 [1].
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10. Acknowledgments
Some parts of this draft stem from [10]. This work is heavily
influenced by [15], which serves as a model for this document.
The authors would like to thanks the following people, who have
provided thoughtful and helpful discussions and/or suggestions, that
have improved this document: Rob Austein, Hannu Flinck, Miika Komu,
Gabriel Montenegro.
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11. References
11.1 Normative references
[1] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987.
[2] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
[3] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA
Considerations Section in RFCs", BCP 26, RFC 2434, October
1998.
[4] Eastlake, D., "DSA KEYs and SIGs in the Domain Name System
(DNS)", RFC 2536, March 1999.
[5] Crawford, M., "Binary Labels in the Domain Name System", RFC
2673, August 1999.
[6] Eastlake, D., "RSA/SHA-1 SIGs and RSA KEYs in the Domain Name
System (DNS)", RFC 3110, May 2001.
[7] Bush, R., Durand, A., Fink, B., Gudmundsson, O. and T. Hain,
"Representing Internet Protocol version 6 (IPv6) Addresses in
the Domain Name System (DNS)", RFC 3363, August 2002.
[8] Klensin, J., "Role of the Domain Name System (DNS)", RFC 3467,
February 2003.
[9] Thomson, S., Huitema, C., Ksinant, V. and M. Souissi, "DNS
Extensions to Support IP Version 6", RFC 3596, October 2003.
[10] Moskowitz, R., Nikander, P. and P. Jokela, "Host Identity
Protocol", draft-moskowitz-hip-09 (work in progress), February
2004.
[11] Moskowitz, R., "Host Identity Protocol Architecture",
draft-moskowitz-hip-arch-05 (work in progress), October 2003.
[12] Nikander, P., "End-Host Mobility and Multi-Homing with Host
Identity Protocol", draft-nikander-hip-mm-01 (work in
progress), January 2004.
[13] Eggert, L. and J. Laganier, "Host Identity Protocol (HIP)
Rendezvous Extensions", draft-eggert-hip-rvs-00 (work in
progress), July 2004.
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11.2 Informative references
[14] Rescorla, E. and B. Korver, "Guidelines for Writing RFC Text on
Security Considerations", draft-iab-sec-cons-00 (work in
progress), August 2002.
[15] Richardson, M., "A method for storing IPsec keying material in
DNS", draft-ietf-ipseckey-rr-09 (work in progress), February
2004.
Authors' Addresses
Pekka Nikander
Ericsson Research Nomadic Lab
JORVAS FIN-02420
FINLAND
Phone: +358 9 299 1
EMail: pekka.nikander@nomadiclab.com
Julien Laganier
LIP (CNRS-INRIA-ENSL-UCBL) & Sun Labs (Sun Microsystems)
180, Avenue de l'Europe
Saint Ismier CEDEX 38334
France
Phone: +33 476 188 815
EMail: ju@sun.com
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