draft-ietf-dnsext-rfc2539bis-dhk-04.txt   draft-ietf-dnsext-rfc2539bis-dhk-05.txt 
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
OBSOLETES: RFC 2539 Donald E. Eastlake 3rd OBSOLETES: RFC 2539 Donald E. Eastlake 3rd
Motorola Laboratories Motorola Laboratories
Expires: February 2005 August 2004 Expires: September 2005 March 2005
Storage of Diffie-Hellman Keying Information in the DNS Storage of Diffie-Hellman Keying Information in the DNS
------- -- -------------- ------ ----------- -- --- --- ------- -- -------------- ------ ----------- -- --- ---
<draft-ietf-dnsext-rfc2539bis-dhk-04.txt> <draft-ietf-dnsext-rfc2539bis-dhk-05.txt>
Status of This Document Status of This Document
By submitting this Internet-Draft, I certify that any applicable By submitting this Internet-Draft, I certify that any applicable
patent or other IPR claims of which I am aware have been disclosed, patent or other IPR claims of which I am aware have been disclosed,
or will be disclosed, and any of which I become aware will be or will be disclosed, and any of which I become aware will be
disclosed, in accordance with RFC 3668. disclosed, in accordance with RFC 3668.
Distribution of this document is unlimited. Comments should be sent Distribution of this document is unlimited. Comments should be sent
to the DNS extensions working group mailing list to the DNS extensions working group mailing list
skipping to change at page 1, line 46 skipping to change at page 1, line 46
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html http://www.ietf.org/shadow.html
Abstract Abstract
The standard method for encoding Diffie-Hellman keys in the Domain The standard method for encoding Diffie-Hellman keys in the Domain
Name System is specified. Name System is specified.
Copyright Copyright
Copyright (C) The Internet Society 2004. Copyright (C) The Internet Society 2005.
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
Acknowledgements Acknowledgements
Part of the format for Diffie-Hellman keys and the description Part of the format for Diffie-Hellman keys and the description
thereof was taken from a work in progress by Ashar Aziz, Tom Markson, thereof was taken from a work in progress by Ashar Aziz, Tom Markson,
and Hemma Prafullchandra. In addition, the following persons and Hemma Prafullchandra. In addition, the following persons
provided useful comments that were incorporated into the predecessor provided useful comments that were incorporated into the predecessor
of this document: Ran Atkinson, Thomas Narten. of this document: Ran Atkinson, Thomas Narten.
skipping to change at page 4, line 15 skipping to change at page 4, line 15
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
in deciding on a p and g, see [RFC 2631]. in deciding on a p and g, see [RFC 2631].
2. Encoding Diffie-Hellman Keying Information 2. Encoding Diffie-Hellman Keying Information
When Diffie-Hellman keys appear within the RDATA portion of a RR, When Diffie-Hellman keys appear within the RDATA portion of a RR,
they are encoded as shown below. they are encoded as shown below.
The period of key validity is not included in this data but is The period of key validity is not included in this data but is
indicated separately, for example by an RR which signs and indicated separately, for example by an RR such as RRSIG which signs
authenticates the RR containing the keying information. and authenticates the RR containing the keying information.
1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 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 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| KEY flags | protocol | algorithm=2 | | KEY flags | protocol | algorithm=2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| prime length (or flag) | prime (p) (or special) / | prime length (or flag) | prime (p) (or special) /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ prime (p) (variable length) | generator length | / prime (p) (variable length) | generator length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| generator (g) (variable length) | | generator (g) (variable length) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| public value length | public value (variable length)/ | public value length | public value (variable length)/
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ public value (g^i mod p) (variable length) | / public value (g^i mod p) (variable length) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Prime length is length of the Diffie-Hellman prime (p) in bytes if it Prime length is the length of the Diffie-Hellman prime (p) in bytes
is 16 or greater. Prime contains the binary representation of the if it is 16 or greater. Prime contains the binary representation of
Diffie-Hellman prime with most significant byte first (i.e., in the Diffie-Hellman prime with most significant byte first (i.e., in
network order). If "prime length" field is 1 or 2, then the "prime" network order). If "prime length" field is 1 or 2, then the "prime"
field is actually an unsigned index into a table of 65,536 field is actually an unsigned index into a table of 65,536
prime/generator pairs and the generator length SHOULD be zero. See prime/generator pairs and the generator length SHOULD be zero. See
Appedix A for defined table entries and Section 4 for information on Appedix A for defined table entries and Section 4 for information on
allocating additional table entries. The meaning of a zero or 3 allocating additional table entries. The meaning of a zero or 3
through 15 value for "prime length" is reserved. through 15 value for "prime length" is reserved.
Generator length is the length of the generator (g) in bytes. Generator length is the length of the generator (g) in bytes.
Generator is the binary representation of generator with most Generator is the binary representation of generator with most
significant byte first. PublicValueLen is the Length of the Public significant byte first. PublicValueLen is the Length of the Public
skipping to change at page 5, line 12 skipping to change at page 5, line 12
representation of the DH public value with most significant byte representation of the DH public value with most significant byte
first. first.
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
3. Performance Considerations 3. Performance Considerations
Current DNS implementations are optimized for small transfers, Current DNS implementations are optimized for small transfers,
typically less than 512 bytes including DNS overhead. Larger typically less than 512 bytes including DNS overhead. Larger
transfers will perform correctly and extensions have been transfers will perform correctly and extensions have been
standardized [RFC 2671] to make larger transfers more efficient, it standardized [RFC 2671] to make larger transfers more efficient. But
is still advisable at this time to make reasonable efforts to it is still advisable at this time to make reasonable efforts to
minimize the size of RR sets containing keying information consistent minimize the size of RR sets containing keying information consistent
with adequate security. with adequate security.
4. IANA Considerations 4. IANA Considerations
Assignment of meaning to Prime Lengths of 0 and 3 through 15 requires Assignment of meaning to Prime Lengths of 0 and 3 through 15 requires
an IETF consensus as defined in [RFC 2434]. an IETF consensus as defined in [RFC 2434].
Well known prime/generator pairs number 0x0000 through 0x07FF can Well known prime/generator pairs number 0x0000 through 0x07FF can
only be assigned by an IETF standards action. [RFC 2539], the only be assigned by an IETF standards action. [RFC 2539], the
Proposed Standard predecessor of this document, assigned 0x0001 Proposed Standard predecessor of this document, assigned 0x0001
through 0x0002. This document assigns 0x0003. Pairs number 0s0800 through 0x0002. This document additionally assigns 0x0003. Pairs
through 0xBFFF can be assigned based on RFC documentation. Pairs number 0s0800 through 0xBFFF can be assigned based on RFC
number 0xC000 through 0xFFFF are available for private use and are documentation. Pairs number 0xC000 through 0xFFFF are available for
not centrally coordinated. Use of such private pairs outside of a private use and are not centrally coordinated. Use of such private
closed environment may result in conflicts and/or security failures. pairs outside of a closed environment may result in conflicts and/or
security failures.
5. Security Considerations 5. Security Considerations
Keying information retrieved from the DNS should not be trusted Keying information retrieved from the DNS should not be trusted
unless (1) it has been securely obtained from a secure resolver or unless (1) it has been securely obtained from a secure resolver or
independently verified by the user and (2) this secure resolver and independently verified by the user and (2) this secure resolver and
secure obtainment or independent verification conform to security secure obtainment or independent verification conform to security
policies acceptable to the user. As with all cryptographic policies acceptable to the user. As with all cryptographic
algorithms, evaluating the necessary strength of the key is important algorithms, evaluating the necessary strength of the key is important
and dependent on security policy. and dependent on security policy.
In addition, the usual Diffie-Hellman key strength considerations In addition, the usual Diffie-Hellman key strength considerations
apply. (p-1)/2 should also be prime, g should be primitive mod p, p apply. (p-1)/2 should also be prime, g should be primitive mod p, p
should be "large", etc. [RFC 2631, Schneier] should be "large", etc. See [RFC 2631, Schneier].
Copyright and Disclaimer Copyright and Disclaimer
Copyright (C) The Internet Society 2004. This document is subject to Copyright (C) The Internet Society 2005. This document is subject to
the rights, licenses and restrictions contained in BCP 78 and except the rights, licenses and restrictions contained in BCP 78 and except
as set forth therein, the authors retain all their rights. as set forth therein, the authors retain all their rights.
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
This document and the information contained herein are provided on an This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
skipping to change at page 7, line 52 skipping to change at page 7, line 52
Algorithms, and Source Code in C" (Second Edition), 1996, John Wiley Algorithms, and Source Code in C" (Second Edition), 1996, John Wiley
and Sons. and Sons.
Author Address Author Address
Donald E. Eastlake 3rd Donald E. Eastlake 3rd
Motorola Laboratories Motorola Laboratories
155 Beaver Street 155 Beaver Street
Milford, MA 01757 USA Milford, MA 01757 USA
Telephone: +1-508-786-7554 (w) Telephone: +1-508-786-7554
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
+1-508-634-2066 (h)
EMail: Donald.Eastlake@motorola.com EMail: Donald.Eastlake@motorola.com
Expiration and File Name Expiration and File Name
This draft expires in February 2005. This draft expires in September 2005.
Its file name is draft-ietf-dnsext-rfc2539bis-dhk-04.txt. Its file name is draft-ietf-dnsext-rfc2539bis-dhk-05.txt.
INTERNET-DRAFT Diffie-Hellman Information in the DNS INTERNET-DRAFT Diffie-Hellman Information in the DNS
Appendix A: Well known prime/generator pairs Appendix A: Well known prime/generator pairs
These numbers are copied from the IPSEC effort where the derivation of These numbers are copied from the IPSEC effort where the derivation of
these values is more fully explained and additional information is available. these values is more fully explained and additional information is
available.
Richard Schroeppel performed all the mathematical and computational Richard Schroeppel performed all the mathematical and computational
work for this appendix. work for this appendix.
A.1. Well-Known Group 1: A 768 bit prime A.1. Well-Known Group 1: A 768 bit prime
The prime is 2^768 - 2^704 - 1 + 2^64 * { [2^638 pi] + 149686 }. Its The prime is 2^768 - 2^704 - 1 + 2^64 * { [2^638 pi] + 149686 }. Its
decimal value is decimal value is
155251809230070893513091813125848175563133404943451431320235 155251809230070893513091813125848175563133404943451431320235
119490296623994910210725866945387659164244291000768028886422 119490296623994910210725866945387659164244291000768028886422
915080371891804634263272761303128298374438082089019628850917 915080371891804634263272761303128298374438082089019628850917
 End of changes. 

This html diff was produced by rfcdiff 1.23, available from http://www.levkowetz.com/ietf/tools/rfcdiff/