One document matched: draft-jiang-dhc-sedhcpv6-02.xml
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<rfc category="std" docName="draft-jiang-dhc-sedhcpv6-02" ipr="trust200902">
<front>
<title abbrev="SeDHCPv6">Secure DHCPv6 with Public Key</title>
<author fullname="Sheng Jiang" initials="S." surname="Jiang">
<organization>Huawei Technologies Co., Ltd</organization>
<address>
<postal>
<street>Q14, Huawei Campus, No.156 Beiqing Road</street>
<city>Hai-Dian District, Beijing, 100095</city>
<country>P.R. China</country>
</postal>
<email>jiangsheng@huawei.com</email>
</address>
</author>
<author fullname="Sean Shen" initials="S." surname="Shen">
<organization>CNNIC</organization>
<address>
<postal>
<street>4, South 4th Street, Zhongguancun</street>
<city>Beijing</city>
<code>100190</code>
<country>P.R. China</country>
</postal>
<email>shenshuo@cnnic.cn</email>
</address>
</author>
<date month="" year="2013" />
<area>Internet Area</area>
<workgroup>DHC Working Group</workgroup>
<keyword>Secure</keyword>
<keyword>DHCPv6</keyword>
<keyword>Public Key</keyword>
<abstract>
<t>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.</t>
</abstract>
</front>
<middle>
<section title="Introduction">
<t>The Dynamic Host Configuration Protocol for IPv6 (DHCPv6, <xref
target="RFC3315"></xref>) enables DHCPv6 servers to pass configuration
parameters. It offers configuration flexibility. If not secured, DHCPv6
is vulnerable to various attacks, particularly spoofing attacks.</t>
<t>This document analyzes the security issues of DHCPv6 in details. This
document provides mechanisms for improving the security of DHCPv6
between client and server:<list style="symbols">
<t>the identity of a DHCPv6 message sender, which can be a DHCPv6
server or a client, can be verified by a recipient.</t>
<t>the integrity of DHCPv6 messages can be checked by the recipient
of the message.</t>
</list></t>
<t>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 <xref target="RFC3315"></xref>.</t>
<t>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, <xref
target="RFC5280"></xref>) or pre-configured sender's public key.
However, the deployment of PKI or pre-configuration is out of the
scope.</t>
<t>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.</t>
</section>
<section title="Requirements Language and Terminology">
<t>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 <xref
target="RFC2119"></xref> 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 <xref
target="RFC2119"></xref> key words.</t>
</section>
<section title="Security Overview of DHCPv6">
<t>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 <xref target="RFC3315"></xref>, security of DHCPv6 message
can be improved.</t>
<t><list style="empty">
<t>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. <xref
target="RFC3315"></xref> 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; <xref target="RFC3315"></xref>
provides no mechanism for doing this. <vspace blankLines="1" />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. <vspace blankLines="1" />Manual key
distribution runs counter to the goal of minimizing the
configuration data needed at each host. <xref
target="RFC3315"></xref> 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. <vspace blankLines="1" />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.</t>
</list></t>
</section>
<section title="Secure DHCPv6 Overview">
<t>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.</t>
<t>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.</t>
<t>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.</t>
<t>This improves communication security of DHCPv6 messages. The
authentication options [RFC3315] may also be used for replay
protection.</t>
<section title="New Components">
<t>The components of the solution specified in this document are as
follows:</t>
<t><list style="symbols">
<t>The node generates a public/private key pair. A DHCPv6 option
is defined that carries the public key. <vspace
blankLines="1" />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.</t>
<t>A signature generated using the private key that protects the
integrity of the DHCPv6 messages and authenticates the identity of
the sender.</t>
<t>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.</t>
</list></t>
</section>
<section title="Support for algorithm agility">
<t>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 <xref
target="RFC4270"></xref>, this document provides a mechanism for
negotiating the use of more secure hashes in the future.</t>
<t>In addition to hash algorithm agility, this document also provides
a mechanism for signature algorithm agility.</t>
<t>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.</t>
</section>
</section>
<section title="Extensions for Secure DHCPv6">
<t>This section extends DHCPv6. Three new options have been defined. The
new options MUST be supported in the Secure DHCPv6 message exchange.</t>
<section anchor="PKOption" title="Public Key Option">
<t>The Public Key option carries the public key of the sender. The
format of the Public Key option is described as follows:</t>
<t><figure align="center">
<artwork><![CDATA[ 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.
]]></artwork>
</figure></t>
</section>
<section anchor="CertOption" title="Certificate Option">
<t>The Certificate option carries the certificate of the sender. The
format of the Certificate option is described as follows:</t>
<t><figure align="center">
<artwork><![CDATA[ 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.
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].
]]></artwork>
</figure></t>
</section>
<section anchor="SigOption" title="Signature Option">
<t>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:</t>
<t><figure align="center">
<artwork><![CDATA[ 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
[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.
]]></artwork>
</figure>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.</t>
</section>
</section>
<section title="Processing Rules and Behaviors">
<t></t>
<section title="Processing Rules of Sender">
<t>The sender of a Secure DHCPv6 message could be a DHCPv6 server or a
DHCPv6 client.</t>
<t>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.</t>
<t>To support Secure DHCPv6, the Secure DHCPv6 enabled sender MUST
construct the DHCPv6 message following the rules defined in <xref
target="RFC3315"></xref>.</t>
<t>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 <xref target="PKOption"></xref>
or <xref target="CertOption"></xref>.</t>
<t>A Secure DHCPv6 message, except for Relay-forward and Relay-reply
messages, MUST contain the Signature option, which MUST be constructed
as explained in <xref target="SigOption"></xref>. 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.</t>
<t>A Relay-forward and relay-reply message MUST NOT contain any Public
Key or Certificate option or Signature Option.</t>
</section>
<section anchor="RuleRecipient" title="Processing Rules of Recipient ">
<t>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.</t>
<t>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 <xref target="RFC5280"></xref>. An implementation may
then create a local trust certificate record.</t>
<t>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.</t>
<t>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, because signature verification is much more computationally
expensive.</t>
<t>The signature field verification MUST show that the signature has
been calculated as specified in <xref target="SigOption"></xref>. 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 <xref
target="RFC3315"></xref>. Messages that do not pass the above tests
MUST be discarded or treated as unsecure messages.</t>
<t>The recipient MAY record the verified public key or certificate for
future authentications.</t>
<t>Furthermore, the node that supports the verification of the Secure
DHCPv6 messages MAY record the following information:</t>
<t><list style="hanging">
<t hangText="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 <xref target="RSA"></xref>.</t>
</list>A Relay-forward or Relay-reply message with any Public Key,
Certificate or the Signature option is invilad. The message SHOULD be
discarded silently.</t>
</section>
<section title="Processing Rules of Relay Agent">
<t>To support Secure DHCPv6, relay agents just need to follow the same
processing rules defined in <xref target="RFC3315"></xref>. 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.</t>
</section>
<section title="Timestamp Check">
<t>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.</t>
<t>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 has a
clock too far from the current time, the timestamp mechanism would not
work.</t>
<t>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):</t>
<t><list style="symbols">
<t>The receive time of the last received and accepted DHCPv6
message. This is called RDlast.</t>
<t>The time stamp in the last received and accepted DHCPv6
message. This is called TSlast.</t>
</list>An verified (for both timestamp check and signature
verification) secure DHCPv6 message initiates the update of the above
variables in the recipient's record.</t>
<t>Recipients MUST check the Timestamp field as follows:</t>
<t><list style="symbols">
<t>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:<list
style="empty">
<t>-Delta < (RDnew - TSnew) < +Delta</t>
</list><vspace blankLines="1" />After the signature verification
also successes, the RDnew and TSnew values SHOULD be stored in the
cache as RDlast and TSlast.</t>
<t>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:<list
style="empty">
<t>TSnew + fuzz > TSlast + (RDnew - RDlast) x (1 - drift) -
fuzz</t>
</list><vspace blankLines="1" />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. <vspace blankLines="1" />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.</t>
</list>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 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.</t>
</section>
</section>
<section anchor="Security" title="Security Considerations">
<t>This document provides new security features to the DHCPv6
protocol.</t>
<t>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.</t>
<t>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.</t>
<t>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.</t>
<t>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.</t>
<t><xref target="RFC6273"></xref> 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.</t>
<t>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
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.</t>
<t>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.</t>
</section>
<section anchor="IANA" title="IANA Considerations">
<t>This document defines three new DHCPv6 <xref target="RFC3315"></xref>
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:</t>
<t><list style="empty">
<t>The Public Key Option (TBA1), described in <xref
target="PKOption"></xref>.</t>
<t>The Certificate Option (TBA2), described in <xref
target="CertOption"></xref>.</t>
<t>The Signature Option (TBA3), described in <xref
target="SigOption"></xref>.</t>
</list>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.</t>
<t>Initial values for these registries are given below. Future
assignments are to be made through Standards Action <xref
target="RFC5226"></xref>. Assignments for each registry consist of a
name, a value and a RFC number where the registry is defined.</t>
<t>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:</t>
<t><figure>
<artwork><![CDATA[ Name | Value | RFCs
-------------------+---------+------------
Reserved | 0x0000 | this document
SHA-1 | 0x0001 | this document
SHA-256 | 0x0002 | this document
]]></artwork>
</figure>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:</t>
<t><figure>
<artwork><![CDATA[ Name | Value | RFCs
-------------------+---------+------------
Reserved | 0x0000 | this document
RSASSA-PKCS1-v1_5 | 0x0001 | this document
]]></artwork>
</figure></t>
</section>
<section anchor="Acknowledgements" title="Acknowledgements">
<t>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.</t>
<t>This document was produced using the xml2rfc tool <xref
target="RFC2629"></xref>.</t>
</section>
<section anchor="changes" title="Change log [RFC Editor: Please remove]">
<t>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.</t>
<t>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.</t>
<t>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.</t>
</section>
</middle>
<back>
<references title="Normative References">
&RFC2119;
<?rfc include='reference.RFC.3315'?>
<?rfc include='reference.RFC.5280'?>
<?rfc include='reference.RFC.5905'?>
<?rfc include='reference.RFC.5996'?>
</references>
<references title="Informative References">
<reference anchor="RSA">
<front>
<title>RSA Encryption Standard, Version 2.1, PKCS 1</title>
<author fullname="">
<organization>RSA Laboratories</organization>
</author>
<date month="November" year="2002" />
</front>
</reference>
<?rfc include='reference.RFC.2629'?>
<?rfc include='reference.RFC.4270'?>
<?rfc include='reference.RFC.5226'?>
<?rfc include='reference.RFC.6273'?>
</references>
</back>
</rfc>
| PAFTECH AB 2003-2026 | 2026-04-23 11:00:27 |