Internet DRAFT - draft-jiang-dhc-sedhcpv6
draft-jiang-dhc-sedhcpv6
DHC Working Group S. Jiang
Internet-Draft Huawei Technologies Co., Ltd
Intended status: Standards Track S. Shen
Expires: April 19, 2014 CNNIC
October 16, 2013
Secure DHCPv6 with Public Key
draft-jiang-dhc-sedhcpv6-02
Abstract
The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) enables
DHCPv6 servers to pass configuration parameters. It offers
configuration flexibility. If not secured, DHCPv6 is vulnerable to
various attacks, particularly spoofing attacks. This document
analyzes the security issues of DHCPv6 and specifies a Secure DHCPv6
mechanism for communication between DHCPv6 client and server. This
mechanism is based on public/private key pairs. The authority of the
sender may depend on either pre-configuration mechanism or Public Key
Infrastructure.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on April 19, 2014.
Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
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publication of this document. Please review these documents
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carefully, as they describe your rights and restrictions with respect
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Requirements Language and Terminology . . . . . . . . . . . . 3
3. Security Overview of DHCPv6 . . . . . . . . . . . . . . . . . 3
4. Secure DHCPv6 Overview . . . . . . . . . . . . . . . . . . . 4
4.1. New Components . . . . . . . . . . . . . . . . . . . . . 5
4.2. Support for algorithm agility . . . . . . . . . . . . . . 5
5. Extensions for Secure DHCPv6 . . . . . . . . . . . . . . . . 5
5.1. Public Key Option . . . . . . . . . . . . . . . . . . . . 6
5.2. Certificate Option . . . . . . . . . . . . . . . . . . . 6
5.3. Signature Option . . . . . . . . . . . . . . . . . . . . 7
6. Processing Rules and Behaviors . . . . . . . . . . . . . . . 8
6.1. Processing Rules of Sender . . . . . . . . . . . . . . . 8
6.2. Processing Rules of Recipient . . . . . . . . . . . . . . 9
6.3. Processing Rules of Relay Agent . . . . . . . . . . . . . 10
6.4. Timestamp Check . . . . . . . . . . . . . . . . . . . . . 10
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14
10. Change log [RFC Editor: Please remove] . . . . . . . . . . . 14
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
11.1. Normative References . . . . . . . . . . . . . . . . . . 14
11.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction
The Dynamic Host Configuration Protocol for IPv6 (DHCPv6, [RFC3315])
enables DHCPv6 servers to pass configuration parameters. It offers
configuration flexibility. If not secured, DHCPv6 is vulnerable to
various attacks, particularly spoofing attacks.
This document analyzes the security issues of DHCPv6 in details.
This document provides mechanisms for improving the security of
DHCPv6 between client and server:
o the identity of a DHCPv6 message sender, which can be a DHCPv6
server or a client, can be verified by a recipient.
o the integrity of DHCPv6 messages can be checked by the recipient
of the message.
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Note: this secure mechanism in this document does not protect the
relay-relevant options, either added by a relay agent toward a server
or added by a server toward a relay agent, are considered less
vulnerable, because they are only transported within operator
networks. Communication between a server and a relay agent, and
communication between relay agents, may be secured through the use of
IPsec, as described in section 21.1 in [RFC3315].
The security mechanisms specified in this document is based on self-
generated public/private key pairs. It also integrates timestamps
for anti-replay. The authentication procedure defined in this
document may depend on either deployed Public Key Infrastructure
(PKI, [RFC5280]) or pre-configured sender's public key. However, the
deployment of PKI or pre-configuration is out of the scope.
Secure DHCPv6 is applicable in environments where physical security
on the link is not assured (such as over wireless) and attacks on
DHCPv6 are a concern.
2. Requirements Language and Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
[RFC2119] when they appear in ALL CAPS. When these words are not in
ALL CAPS (such as "should" or "Should"), they have their usual
English meanings, and are not to be interpreted as [RFC2119] key
words.
3. Security Overview of DHCPv6
DHCPv6 is a client/server protocol that provides managed
configuration of devices. It enables DHCPv6 server to automatically
configure relevant network parameters on clients. In the basic
DHCPv6 specification [RFC3315], security of DHCPv6 message can be
improved.
The basic DHCPv6 specifications can optionally authenticate the
origin of messages and validate the integrity of messages using an
authentication option with a symmetric key pair. [RFC3315] relies
on pre-established secret keys. For any kind of meaningful
security, each DHCPv6 client would need to be configured with its
own secret key; [RFC3315] provides no mechanism for doing this.
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For the key of the hash function, there are two key management
mechanisms. Firstly, the key management is done out of band,
usually through some manual process. For example, operators can
set up a key database for both servers and clients which the
client obtains a key before running DHCPv6.
Manual key distribution runs counter to the goal of minimizing the
configuration data needed at each host. [RFC3315] provides an
additional mechanism for preventing off-network timing attacks
using the Reconfigure message: the Reconfigure Key authentication
method. However, this method provides no message integrity or
source integrity check. This key is transmitted in plaintext.
In comparison, the public/private key security mechanism allows
the keys to be generated by the sender, and allows the public key
database on the recipient to be populated opportunistically or
manually, depending on the degree of confidence desired in a
specific application. PKI security mechanism is simpler in the
local key management respect.
4. Secure DHCPv6 Overview
To solve the above mentioned security issues, this document
introduces the use of public/private key pair mechanism into DHCPv6,
also with timestamp. The authority of the sender may depend on
either pre-configuration mechanism or PKI. By combining with the
signatures, sender identity can be verified and messages protected.
This document introduces a Secure DHCPv6 mechanism that uses a public
/private key pair to secure the DHCPv6 protocol. It has two modes;
in both modes, the sender has a public/private key pair. In the
first mode, the public key of the sender is pre-shared with the
recipient, either opportunistically or through a manual process. In
the second mode, the sender has a certificate for its public key,
signed by a Certificate Authority that is trusted by the recipient.
It is possible for the same public key to be used with different
recipients in both modes.
In this document, we introduce a public key option, a certificate
option and a signature options with a corresponding verification
mechanism. Timestamp is integrated into signature options. A DHCPv6
message (from a server or a client), with either a public key or
certificate option, and carrying a digital signature, can be verified
by the recipient for both the timestamp and authentication, then
process the payload of the DHCPv6 message only if the validation is
successful. Because the sender can be a DHCPv6 server or a client,
the end-to-end security protection can be from DHCPv6 servers to or
clients, or from clients to DHCPv6 servers.
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This improves communication security of DHCPv6 messages. The
authentication options [RFC3315] may also be used for replay
protection.
4.1. New Components
The components of the solution specified in this document are as
follows:
o The node generates a public/private key pair. A DHCPv6 option is
defined that carries the public key.
The node may also obtain a certificate from a Certificate
Authority that can be used to establish the trustworthiness of the
node. A second option is defined to carry the certificate.
Because the certificate contains the public key, there is never a
need to send both options at the same time.
o A signature generated using the private key that protects the
integrity of the DHCPv6 messages and authenticates the identity of
the sender.
o A timestamp, to detect and prevent packet replay. The secure
DHCPv6 nodes need to meet some accuracy requirements and be synced
to global time, while the timestamp checking mechanism allows a
configurable time value for clock drift.
4.2. Support for algorithm agility
Hash functions are used to provide message integrity checks. In
order to provide a means of addressing problems that may emerge in
the future with existing hash algorithms, as recommended in
[RFC4270], this document provides a mechanism for negotiating the use
of more secure hashes in the future.
In addition to hash algorithm agility, this document also provides a
mechanism for signature algorithm agility.
The support for algorithm agility in this document is mainly a
unilateral notification mechanism from sender to recipient. If the
recipient does not support the algorithm used by the sender, it
cannot authenticate the message. Senders in a same administrative
domain are not required to upgrade to a new algorithm simultaneously.
5. Extensions for Secure DHCPv6
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This section extends DHCPv6. Three new options have been defined.
The new options MUST be supported in the Secure DHCPv6 message
exchange.
5.1. Public Key Option
The Public Key option carries the public key of the sender. The
format of the Public Key option is described as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OPTION_Public_Key | option-len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. Public Key (variable length) .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
option-code OPTION_PK_PARAMETER (TBA1).
option-len Length of public key in octets.
Public Key A variable-length field containing public key. The
key MUST be represented as a lower-case hexadecimal
string with the most significant octet of the key
first.
5.2. Certificate Option
The Certificate option carries the certificate of the sender. The
format of the Certificate option is described as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OPTION_Certificate | option-len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. Certificate (variable length) .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
option-code OPTION_CERT_PARAMETER (TBA2).
option-len Length of certificate in octets.
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Certificate A variable-length field containing certificate. The
encoding of certificate and certificate data MUST
be in format as defined in Section 3.6, [RFC5996].
5.3. Signature Option
The Signature option allows public key-based signatures to be
attached to a DHCPv6 message. The Signature option could be any
place within the DHCPv6 message. It protects the entire DHCPv6
header and options, except for the Authentication Option. The format
of the Signature option is described as follows:
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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| OPTION_SIGNATURE | option-len |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| HA-id | SA-id |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Timestamp (64-bit) |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
. Signature (variable length) .
. .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
option-code OPTION_SIGNATURE (TBA3).
option-len 12 + Length of Signature field in octets.
HA-id Hash Algorithm id. The hash algorithm is used for
computing the signature result. This design is
adopted in order to provide hash algorithm agility.
The value is from the Hash Algorithm for Secure
DHCPv6 registry in IANA. The initial values are
assigned for SHA-1 is 0x0001.
SA-id Signature Algorithm id. The signature algorithm is
used for computing the signature result. This
design is adopted in order to provide signature
algorithm agility. The value is from the Signature
Algorithm for Secure DHCPv6 registry in IANA. The
initial values are assigned for RSASSA-PKCS1-v1_5
is 0x0001.
Timestamp The current time of day (NTP-format timestamp
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[RFC5905] in UTC (Coordinated Universal Time), a
64-bit unsigned fixed-point number, in seconds
relative to 0h on 1 January 1900.). It can reduce
the danger of replay attacks.
Signature A variable-length field containing a digital
signature. The signature value is computed with
the hash algorithm and the signature algorithm,
as described in HA-id and SA-id. The signature
constructed by using the sender's private key
protects the following sequence of octets:
1. The DHCPv6 message header.
2. All DHCPv6 options including the Signature
option (fill the signature field with zeroes)
except for the Authentication Option.
The signature filed MUST be padded, with all 0, to
the next octet boundary if its size is not an even
multiple of 8 bits. The padding length depends on
the signature algorithm, which is indicated in the
SA-id field.
Note: if both signature and authentication option are presented,
signature option does not protect authentication option. It is
because both needs to apply hash algorithm to whole message, so there
must be a clear order and there could be only one last-created
option. In order to avoid update RFC3315 because of changing auth
option, the authors chose not include authentication option in the
signature.
6. Processing Rules and Behaviors
6.1. Processing Rules of Sender
The sender of a Secure DHCPv6 message could be a DHCPv6 server or a
DHCPv6 client.
The node must have a public/private key pair in order to create
Secure DHCPv6 messages. The node may have a certificate which is
signed by a CA trusted by both sender and recipient.
To support Secure DHCPv6, the Secure DHCPv6 enabled sender MUST
construct the DHCPv6 message following the rules defined in
[RFC3315].
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A Secure DHCPv6 message, except for Relay-forward and Relay-reply
messages, MUST contain either a the Public Key or Certificate option,
which MUST contructed as explained in Section 5.1 or Section 5.2.
A Secure DHCPv6 message, except for Relay-forward and Relay-reply
messages, MUST contain the Signature option, which MUST be
constructed as explained in Section 5.3. It protects the message
header and the message payload and all DHCPv6 options except for the
Signature option itself and the Authentication Option. Within the
Signature option the Timestamp field SHOULD be set to the current
time, according to sender's real time clock.
A Relay-forward and relay-reply message MUST NOT contain any Public
Key or Certificate option or Signature Option.
6.2. Processing Rules of Recipient
When receiving a DHCPv6 message, except for Relay-Forward and Relay-
Reply messages, a Secure DHCPv6 enabled recipient SHOULD discard the
DHCPv6 message if the Signature option is absent, or both the Public
Key and Certificate option is absent, or both the Public Key and
Certificate option are presented. If all three options are absent,
the recipient MAY fall back the unsecure DHCPv6 model.
The recipient SHOULD first check the authority of this sender. If
the sender uses a public key, the recipient SHOULD validate it by
finding a match public key from the local trust public key list,
which is pre-configured or recorded from previous communications. A
local trust public key list is a data table maintained by the
recipient. It restores public keys from all trustworthy senders. A
fast search index may be created for this data table. If the sender
uses certificate, the recipient SHOULD validate the sender's
certificate following the rules defined in [RFC5280]. An
implementation may then create a local trust certificate record.
The recipient may choose to further process the message from a sender
for which no authorization information exists. By recording the key
that was used by the sender, when the first time it is seen, the
recipient can make a leap of faith that the sender is trustworthy.
If no evidence to the contrary surfaces, the recipient can then
validate the sender as trustworthy when it subsequently sees the same
key used to sign messages from the same server.
At this point, the recipient has either recognized the authorization
of the sender, or decided to attempt a leap of faith. The recipient
MUST now authenticate the sender by verifying the Signature and
checking timestamp. The order of two procedures is left as an
implementation decision. It is RECOMMENDED to check timestamp first,
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because signature verification is much more computationally
expensive.
The signature field verification MUST show that the signature has
been calculated as specified in Section 5.3. Only the messages that
get through both the signature verifications and timestamp check are
accepted as secured DHCPv6 messages and continue to be handled for
their contained DHCPv6 options as defined in [RFC3315]. Messages
that do not pass the above tests MUST be discarded or treated as
unsecure messages.
The recipient MAY record the verified public key or certificate for
future authentications.
Furthermore, the node that supports the verification of the Secure
DHCPv6 messages MAY record the following information:
Minbits The minimum acceptable key length for public keys. An upper
limit MAY also be set for the amount of computation needed when
verifying packets that use these security associations. The
appropriate lengths SHOULD be set according to the signature
algorithm and also following prudent cryptographic practice. For
example, minimum length 1024 and upper limit 2048 may be used for
RSA [RSA].
A Relay-forward or Relay-reply message with any Public Key,
Certificate or the Signature option is invilad. The message SHOULD
be discarded silently.
6.3. Processing Rules of Relay Agent
To support Secure DHCPv6, relay agents just need to follow the same
processing rules defined in [RFC3315]. There is nothing more the
relay agents have to do, either verify the messages from client or
server, or add any secure DHCPv6 options. Actually, be definition in
this document, relay agents MUST NOT add any secure DHCPv6 options.
6.4. Timestamp Check
Recipients SHOULD be configured with an allowed timestamp Delta
value, a "fuzz factor" for comparisons, and an allowed clock drift
parameter. The recommended default value for the allowed Delta is
300 seconds (5 minutes); for fuzz factor 1 second; and for clock
drift, 0.01 second.
Note: the Timestamp mechanism is based on the assumption that
communication peers have rough synchronized clocks, with certain
allowed clock drift. So, accurate clock is not necessary. If one
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has a clock too far from the current time, the timestamp mechanism
would not work.
To facilitate timestamp checking, each recipient SHOULD store the
following information for each sender, from which at least one
accepted secure DHCPv6 message is successfully verified (for both
timestamp check and signature verification):
o The receive time of the last received and accepted DHCPv6 message.
This is called RDlast.
o The time stamp in the last received and accepted DHCPv6 message.
This is called TSlast.
An verified (for both timestamp check and signature verification)
secure DHCPv6 message initiates the update of the above variables in
the recipient's record.
Recipients MUST check the Timestamp field as follows:
o When a message is received from a new peer (i.e., one that is not
stored in the cache), the received timestamp, TSnew, is checked,
and the message is accepted if the timestamp is recent enough to
the reception time of the packet, RDnew:
-Delta < (RDnew - TSnew) < +Delta
After the signature verification also successes, the RDnew and
TSnew values SHOULD be stored in the cache as RDlast and TSlast.
o When a message is received from a known peer (i.e., one that
already has an entry in the cache), the timestamp is checked
against the previously received Secure DHCPv6 message:
TSnew + fuzz > TSlast + (RDnew - RDlast) x (1 - drift) - fuzz
If this inequality does not hold, the recipient SHOULD silently
discard the message. If, on the other hand, the inequality holds,
the recipient SHOULD process the message.
Moreover, if the above inequality holds and TSnew > TSlast, the
recipient SHOULD update RDlast and TSlast after the signature
verification also successes. Otherwise, the recipient MUST NOT
update RDlast or TSlast.
An implementation MAY use some mechanism such as a timestamp cache to
strengthen resistance to replay attacks. When there is a very large
number of nodes on the same link, or when a cache filling attack is
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in progress, it is possible that the cache holding the most recent
timestamp per sender will become full. In this case, the node MUST
remove some entries from the cache or refuse some new requested
entries. The specific policy as to which entries are preferred over
others is left as an implementation decision.
7. Security Considerations
This document provides new security features to the DHCPv6 protocol.
Using public key based security mechanism and its verification
mechanism in DHCPv6 message exchanging provides the authentication
and data integrity protection. Timestamp mechanism provides anti-
replay function.
The Secure DHCPv6 mechanism is based on the pre-condition that the
recipient knows the public key of senders or the sender's certificate
can be verified through a trust CA. It prevents DHCPv6 server
spoofing. The clients may decline the DHCPv6 messages from unknown/
unverified servers, which may be fake servers; or may prefer DHCPv6
messages from known/verified servers over unsigned messages or
messages from unknown/unverified servers. The pre-configuration
operation also needs to be protected, which is out of scope. The
deployment of PKI is also out of scope.
However, when a DHCPv6 client first encounters a new public key or
new unverified certificate, it can make a leap of faith. If the
DHCPv6 server that used that public key or certificate is in fact
legitimate, then all future communication with that DHCPv6 server can
be protected by caching the public key. This does not provide
complete security, but it limits the opportunity to mount an attack
on a specific DHCPv6 client to the first time it communicates with a
new DHCPv6 server.
Downgrade attacks cannot be avoided if nodes are configured to accept
both secured and unsecured messages. A future specification may
provide a mechanism on how to treat unsecured DHCPv6 messages.
[RFC6273] has analyzed possible threats to the hash algorithms used
in SEND. Since the Secure DHCPv6 defined in this document uses the
same hash algorithms in similar way to SEND, analysis results could
be applied as well: current attacks on hash functions do not
constitute any practical threat to the digital signatures used in the
signature algorithm in the Secure DHCPv6.
A window of vulnerability for replay attacks exists until the
timestamp expires. Secure DHCPv6 nodes are protected against replay
attacks as long as they cache the state created by the message
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containing the timestamp. The cached state allows the node to
protect itself against replayed messages. However, once the node
flushes the state for whatever reason, an attacker can re-create the
state by replaying an old message while the timestamp is still valid.
Attacks against time synchronization protocols such as NTP [RFC5905]
may cause Secure DHCPv6 nodes to have an incorrect timestamp value.
This can be used to launch replay attacks, even outside the normal
window of vulnerability. To protect against these attacks, it is
recommended that Secure DHCPv6 nodes keep independently maintained
clocks or apply suitable security measures for the time
synchronization protocols.
8. IANA Considerations
This document defines three new DHCPv6 [RFC3315] options. The IANA
is requested to assign values for these three options from the DHCP
Option Codes table of the DHCPv6 Parameters registry. The three
options are:
The Public Key Option (TBA1), described in Section 5.1.
The Certificate Option (TBA2), described in Section 5.2.
The Signature Option (TBA3), described in Section 5.3.
The IANA is also requested to add two new registry tables to the
DHCPv6 Parameters registry. The two tables are the Hash Algorithm
for Secure DHCPv6 table and the Signature Algorithm for Secure DHCPv6
table.
Initial values for these registries are given below. Future
assignments are to be made through Standards Action [RFC5226].
Assignments for each registry consist of a name, a value and a RFC
number where the registry is defined.
Hash Algorithm for Secure DHCPv6. The values in this table are
16-bit unsigned integers. The following initial values are assigned
for Hash Algorithm for Secure DHCPv6 in this document:
Name | Value | RFCs
-------------------+---------+------------
Reserved | 0x0000 | this document
SHA-1 | 0x0001 | this document
SHA-256 | 0x0002 | this document
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Signature Algorithm for Secure DHCPv6. The values in this table are
16-bit unsigned integers. The following initial values are assigned
for Signature Algorithm for Secure DHCPv6 in this document:
Name | Value | RFCs
-------------------+---------+------------
Reserved | 0x0000 | this document
RSASSA-PKCS1-v1_5 | 0x0001 | this document
9. Acknowledgements
The authors would like to thank Bernie Volz, Ted Lemon, Ralph Droms,
Jari Arkko, Sean Turner, Stephen Kent, Thomas Huth, David Schumacher,
Dacheng Zhang, Francis Dupont and other members of the IETF DHC
working groups for their valuable comments.
This document was produced using the xml2rfc tool [RFC2629].
10. Change log [RFC Editor: Please remove]
draft-jiang-dhc-sedhcpv6-01: removed protection between relay agent
and server due to complexity, following the comments from Ted Lemon,
Bernie Volz. 2013-10-16.
draft-jiang-dhc-sedhcpv6-01: update according to review comments from
Ted Lemon, Bernie Volz, Ralph Droms. Separated Public Key/
Certificate option into two options. Refined many detailed
processes. 2013-10-08.
draft-jiang-dhc-sedhcpv6-00: original version, this draft is a
replacement of draft-ietf-dhc-secure-dhcpv6, which reached IESG and
dead because of consideration regarding to CGA. The authors followed
the suggestion from IESG making a general public key based mechanism.
2013-06-29.
11. References
11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
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[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, May 2008.
[RFC5905] Mills, D., Martin, J., Burbank, J., and W. Kasch, "Network
Time Protocol Version 4: Protocol and Algorithms
Specification", RFC 5905, June 2010.
[RFC5996] Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen,
"Internet Key Exchange Protocol Version 2 (IKEv2)", RFC
5996, September 2010.
11.2. Informative References
[RFC2629] Rose, M., "Writing I-Ds and RFCs using XML", RFC 2629,
June 1999.
[RFC4270] Hoffman, P. and B. Schneier, "Attacks on Cryptographic
Hashes in Internet Protocols", RFC 4270, November 2005.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
[RFC6273] Kukec, A., Krishnan, S., and S. Jiang, "The Secure
Neighbor Discovery (SEND) Hash Threat Analysis", RFC 6273,
June 2011.
[RSA] RSA Laboratories, "RSA Encryption Standard, Version 2.1,
PKCS 1", November 2002.
Authors' Addresses
Sheng Jiang
Huawei Technologies Co., Ltd
Q14, Huawei Campus, No.156 Beiqing Road
Hai-Dian District, Beijing, 100095
P.R. China
Email: jiangsheng@huawei.com
Jiang & Shen Expires April 19, 2014 [Page 15]
Internet-Draft SeDHCPv6 October 2013
Sean Shen
CNNIC
4, South 4th Street, Zhongguancun
Beijing 100190
P.R. China
Email: shenshuo@cnnic.cn
Jiang & Shen Expires April 19, 2014 [Page 16]
