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diff --git a/contrib/bind9/doc/rfc/rfc2539.txt b/contrib/bind9/doc/rfc/rfc2539.txt deleted file mode 100644 index cf32523..0000000 --- a/contrib/bind9/doc/rfc/rfc2539.txt +++ /dev/null @@ -1,395 +0,0 @@ - - - - - - -Network Working Group D. Eastlake -Request for Comments: 2539 IBM -Category: Standards Track March 1999 - - - Storage of Diffie-Hellman Keys in the Domain Name System (DNS) - -Status of this Memo - - This document specifies an Internet standards track protocol for the - Internet community, and requests discussion and suggestions for - improvements. Please refer to the current edition of the "Internet - Official Protocol Standards" (STD 1) for the standardization state - and status of this protocol. Distribution of this memo is unlimited. - -Copyright Notice - - Copyright (C) The Internet Society (1999). All Rights Reserved. - -Abstract - - A standard method for storing Diffie-Hellman keys in the Domain Name - System is described which utilizes DNS KEY resource records. - -Acknowledgements - - Part of the format for Diffie-Hellman keys and the description - thereof was taken from a work in progress by: - - Ashar Aziz <ashar.aziz@eng.sun.com> - Tom Markson <markson@incog.com> - Hemma Prafullchandra <hemma@eng.sun.com> - - In addition, the following person provided useful comments that have - been incorporated: - - Ran Atkinson <rja@inet.org> - Thomas Narten <narten@raleigh.ibm.com> - - - - - - - - - - - - - -Eastlake Standards Track [Page 1] - -RFC 2539 Diffie-Hellman Keys in the DNS March 1999 - - -Table of Contents - - Abstract...................................................1 - Acknowledgements...........................................1 - 1. Introduction............................................2 - 1.1 About This Document....................................2 - 1.2 About Diffie-Hellman...................................2 - 2. Diffie-Hellman KEY Resource Records.....................3 - 3. Performance Considerations..............................4 - 4. IANA Considerations.....................................4 - 5. Security Considerations.................................4 - References.................................................5 - Author's Address...........................................5 - Appendix A: Well known prime/generator pairs...............6 - A.1. Well-Known Group 1: A 768 bit prime..................6 - A.2. Well-Known Group 2: A 1024 bit prime.................6 - Full Copyright Notice......................................7 - -1. Introduction - - The Domain Name System (DNS) is the current global hierarchical - replicated distributed database system for Internet addressing, mail - proxy, and similar information. The DNS has been extended to include - digital signatures and cryptographic keys as described in [RFC 2535]. - Thus the DNS can now be used for secure key distribution. - -1.1 About This Document - - This document describes how to store Diffie-Hellman keys in the DNS. - Familiarity with the Diffie-Hellman key exchange algorithm is assumed - [Schneier]. - -1.2 About Diffie-Hellman - - Diffie-Hellman requires two parties to interact to derive keying - information which can then be used for authentication. Since DNS SIG - RRs are primarily used as stored authenticators of zone information - for many different resolvers, no Diffie-Hellman algorithm SIG RR is - defined. For example, assume that two parties have local secrets "i" - and "j". Assume they each respectively calculate X and Y as follows: - - X = g**i ( mod p ) Y = g**j ( mod p ) - - They exchange these quantities and then each calculates a Z as - follows: - - Zi = Y**i ( mod p ) Zj = X**j ( mod p ) - - - - -Eastlake Standards Track [Page 2] - -RFC 2539 Diffie-Hellman Keys in the DNS March 1999 - - - shared secret between the two parties that an adversary who does not - know i or j will not be able to learn from the exchanged messages - (unless the adversary can derive i or j by performing a discrete - logarithm mod p which is hard for strong p and g). - - The private key for each party is their secret i (or j). The public - key is the pair p and g, which must be the same for the parties, and - their individual X (or Y). - -2. Diffie-Hellman KEY Resource Records - - Diffie-Hellman keys are stored in the DNS as KEY RRs using algorithm - number 2. The structure of the RDATA portion of this RR is as shown - below. The first 4 octets, including the flags, protocol, and - algorithm fields are common to all KEY RRs as described in [RFC - 2535]. The remainder, from prime length through public value is the - "public key" part of the KEY RR. The period of key validity is not in - the KEY RR but is indicated by the SIG RR(s) which signs and - authenticates the KEY RR(s) at that domain name. - - 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 - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | KEY flags | protocol | algorithm=2 | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | prime length (or flag) | prime (p) (or special) / - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - / prime (p) (variable length) | generator length | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | generator (g) (variable length) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | public value length | public value (variable length)/ - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - / public value (g^i mod p) (variable length) | - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - - Prime length is length of the Diffie-Hellman prime (p) in bytes if it - is 16 or greater. Prime contains the binary representation of 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" - field is actually an unsigned index into a table of 65,536 - prime/generator pairs and the generator length SHOULD be zero. See - Appedix A for defined table entries and Section 4 for information on - allocating additional table entries. The meaning of a zero or 3 - through 15 value for "prime length" is reserved. - - - - - - -Eastlake Standards Track [Page 3] - -RFC 2539 Diffie-Hellman Keys in the DNS March 1999 - - - Generator length is the length of the generator (g) in bytes. - Generator is the binary representation of generator with most - significant byte first. PublicValueLen is the Length of the Public - Value (g**i (mod p)) in bytes. PublicValue is the binary - representation of the DH public value with most significant byte - first. - - The corresponding algorithm=2 SIG resource record is not used so no - format for it is defined. - -3. Performance Considerations - - Current DNS implementations are optimized for small transfers, - typically less than 512 bytes including overhead. While larger - transfers will perform correctly and work is underway to make larger - transfers more efficient, it is still advisable to make reasonable - efforts to minimize the size of KEY RR sets stored within the DNS - consistent with adequate security. Keep in mind that in a secure - zone, an authenticating SIG RR will also be returned. - -4. IANA Considerations - - Assignment of meaning to Prime Lengths of 0 and 3 through 15 requires - an IETF consensus. - - Well known prime/generator pairs number 0x0000 through 0x07FF can - only be assigned by an IETF standards action and this Proposed - Standard assigns 0x0001 through 0x0002. Pairs number 0s0800 through - 0xBFFF can be assigned based on RFC documentation. Pairs number - 0xC000 through 0xFFFF are available for private use and are not - centrally coordinated. Use of such private pairs outside of a closed - environment may result in conflicts. - -5. Security Considerations - - Many of the general security consideration in [RFC 2535] apply. Keys - retrieved from the DNS should not be trusted unless (1) they have - been securely obtained from a secure resolver or independently - verified by the user and (2) this secure resolver and secure - obtainment or independent verification conform to security policies - acceptable to the user. As with all cryptographic algorithms, - evaluating the necessary strength of the key is important and - dependent on local policy. - - In addition, the usual Diffie-Hellman key strength considerations - apply. (p-1)/2 should also be prime, g should be primitive mod p, p - should be "large", etc. [Schneier] - - - - -Eastlake Standards Track [Page 4] - -RFC 2539 Diffie-Hellman Keys in the DNS March 1999 - - -References - - [RFC 1034] Mockapetris, P., "Domain Names - Concepts and - Facilities", STD 13, RFC 1034, November 1987. - - [RFC 1035] Mockapetris, P., "Domain Names - Implementation and - Specification", STD 13, RFC 1035, November 1987. - - [RFC 2535] Eastlake, D., "Domain Name System Security Extensions", - RFC 2535, March 1999. - - [Schneier] Bruce Schneier, "Applied Cryptography: Protocols, - Algorithms, and Source Code in C", 1996, John Wiley and - Sons - -Author's Address - - Donald E. Eastlake 3rd - IBM - 65 Shindegan Hill Road, RR #1 - Carmel, NY 10512 - - Phone: +1-914-276-2668(h) - +1-914-784-7913(w) - Fax: +1-914-784-3833(w) - EMail: dee3@us.ibm.com - - - - - - - - - - - - - - - - - - - - - - - - - -Eastlake Standards Track [Page 5] - -RFC 2539 Diffie-Hellman Keys in the DNS March 1999 - - -Appendix A: Well known prime/generator pairs - - These numbers are copied from the IPSEC effort where the derivation - of these values is more fully explained and additional information is - available. Richard Schroeppel performed all the mathematical and - computational work for this appendix. - -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 - decimal value is - 155251809230070893513091813125848175563133404943451431320235 - 119490296623994910210725866945387659164244291000768028886422 - 915080371891804634263272761303128298374438082089019628850917 - 0691316593175367469551763119843371637221007210577919 - - Prime modulus: Length (32 bit words): 24, Data (hex): - FFFFFFFF FFFFFFFF C90FDAA2 2168C234 C4C6628B 80DC1CD1 - 29024E08 8A67CC74 020BBEA6 3B139B22 514A0879 8E3404DD - EF9519B3 CD3A431B 302B0A6D F25F1437 4FE1356D 6D51C245 - E485B576 625E7EC6 F44C42E9 A63A3620 FFFFFFFF FFFFFFFF - - Generator: Length (32 bit words): 1, Data (hex): 2 - -A.2. Well-Known Group 2: A 1024 bit prime - - The prime is 2^1024 - 2^960 - 1 + 2^64 * { [2^894 pi] + 129093 }. - Its decimal value is - 179769313486231590770839156793787453197860296048756011706444 - 423684197180216158519368947833795864925541502180565485980503 - 646440548199239100050792877003355816639229553136239076508735 - 759914822574862575007425302077447712589550957937778424442426 - 617334727629299387668709205606050270810842907692932019128194 - 467627007 - - Prime modulus: Length (32 bit words): 32, Data (hex): - FFFFFFFF FFFFFFFF C90FDAA2 2168C234 C4C6628B 80DC1CD1 - 29024E08 8A67CC74 020BBEA6 3B139B22 514A0879 8E3404DD - EF9519B3 CD3A431B 302B0A6D F25F1437 4FE1356D 6D51C245 - E485B576 625E7EC6 F44C42E9 A637ED6B 0BFF5CB6 F406B7ED - EE386BFB 5A899FA5 AE9F2411 7C4B1FE6 49286651 ECE65381 - FFFFFFFF FFFFFFFF - - Generator: Length (32 bit words): 1, Data (hex): 2 - - - - - - - -Eastlake Standards Track [Page 6] - -RFC 2539 Diffie-Hellman Keys in the DNS March 1999 - - -Full Copyright Statement - - Copyright (C) The Internet Society (1999). All Rights Reserved. - - This document and translations of it may be copied and furnished to - others, and derivative works that comment on or otherwise explain it - or assist in its implementation may be prepared, copied, published - and distributed, in whole or in part, without restriction of any - kind, provided that the above copyright notice and this paragraph are - included on all such copies and derivative works. However, this - document itself may not be modified in any way, such as by removing - the copyright notice or references to the Internet Society or other - Internet organizations, except as needed for the purpose of - developing Internet standards in which case the procedures for - copyrights defined in the Internet Standards process must be - followed, or as required to translate it into languages other than - English. - - The limited permissions granted above are perpetual and will not be - revoked by the Internet Society or its successors or assigns. - - This document and the information contained herein is provided on an - "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING - TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING - BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION - HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF - MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. - - - - - - - - - - - - - - - - - - - - - - - - -Eastlake Standards Track [Page 7] - |
