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diff --git a/contrib/bind9/doc/draft/draft-ietf-dnsext-rfc2536bis-dsa-06.txt b/contrib/bind9/doc/draft/draft-ietf-dnsext-rfc2536bis-dsa-06.txt deleted file mode 100644 index 5b6d655..0000000 --- a/contrib/bind9/doc/draft/draft-ietf-dnsext-rfc2536bis-dsa-06.txt +++ /dev/null @@ -1,464 +0,0 @@ - -INTERNET-DRAFT DSA Information in the DNS -OBSOLETES: RFC 2536 Donald E. Eastlake 3rd - Motorola Laboratories -Expires: January 2006 July 2005 - - - DSA Keying and Signature Information in the DNS - --- ------ --- --------- ----------- -- --- --- - <draft-ietf-dnsext-rfc2536bis-dsa-06.txt> - Donald E. Eastlake 3rd - - -Status of This Document - - By submitting this Internet-Draft, each author represents that any - applicable patent or other IPR claims of which he or she is aware - have been or will be disclosed, and any of which he or she becomes - aware will be disclosed, in accordance with Section 6 of BCP 79. - - Distribution of this document is unlimited. Comments should be sent - to the DNS extensions working group mailing list - <namedroppers@ops.ietf.org>. - - Internet-Drafts are working documents of the Internet Engineering - Task Force (IETF), its areas, and its working groups. Note that - other groups may also distribute working documents as Internet- - Drafts. - - Internet-Drafts are draft documents valid for a maximum of six months - and may be updated, replaced, or obsoleted by other documents at any - time. It is inappropriate to use Internet-Drafts as reference - material or to cite them other than a "work in progress." - - The list of current Internet-Drafts can be accessed at - http://www.ietf.org/1id-abstracts.html - - The list of Internet-Draft Shadow Directories can be accessed at - http://www.ietf.org/shadow.html - - -Abstract - - The standard method of encoding US Government Digital Signature - Algorithm keying and signature information for use in the Domain Name - System is specified. - - -Copyright Notice - - Copyright (C) The Internet Society 2005. All Rights Reserved. - - - - - -D. Eastlake 3rd [Page 1] - - -INTERNET-DRAFT DSA Information in the DNS - - -Table of Contents - - Status of This Document....................................1 - Abstract...................................................1 - Copyright Notice...........................................1 - - Table of Contents..........................................2 - - 1. Introduction............................................3 - 2. DSA Keying Information..................................3 - 3. DSA Signature Information...............................4 - 4. Performance Considerations..............................4 - 5. Security Considerations.................................5 - 6. IANA Considerations.....................................5 - Copyright and Disclaimer...................................5 - - Normative References.......................................7 - Informative References.....................................7 - - Authors Address............................................8 - Expiration and File Name...................................8 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -D. Eastlake 3rd [Page 2] - - -INTERNET-DRAFT DSA Information in the DNS - - -1. Introduction - - The Domain Name System (DNS) is the global hierarchical replicated - distributed database system for Internet addressing, mail proxy, and - other information [RFC 1034, 1035]. The DNS has been extended to - include digital signatures and cryptographic keys as described in - [RFC 4033, 4034, 4035] and additional work is underway which would - require the storage of keying and signature information in the DNS. - - This document describes how to encode US Government Digital Signature - Algorithm (DSA) keys and signatures in the DNS. Familiarity with the - US Digital Signature Algorithm is assumed [FIPS 186-2, Schneier]. - - - -2. DSA Keying Information - - When DSA public keys are stored in the DNS, the structure of the - relevant part of the RDATA part of the RR being used is the fields - listed below in the order given. - - The period of key validity is not included in this data but is - indicated separately, for example by an RR such as RRSIG which signs - and authenticates the RR containing the keying information. - - Field Size - ----- ---- - T 1 octet - Q 20 octets - P 64 + T*8 octets - G 64 + T*8 octets - Y 64 + T*8 octets - - As described in [FIPS 186-2] and [Schneier], T is a key size - parameter chosen such that 0 <= T <= 8. (The meaning if the T octet - is greater than 8 is reserved and the remainder of the data may have - a different format in that case.) Q is a prime number selected at - key generation time such that 2**159 < Q < 2**160. Thus Q is always - 20 octets long and, as with all other fields, is stored in "big- - endian" network order. P, G, and Y are calculated as directed by the - [FIPS 186-2] key generation algorithm [Schneier]. P is in the range - 2**(511+64T) < P < 2**(512+64T) and thus is 64 + 8*T octets long. G - and Y are quantities modulo P and so can be up to the same length as - P and are allocated fixed size fields with the same number of octets - as P. - - During the key generation process, a random number X must be - generated such that 1 <= X <= Q-1. X is the private key and is used - in the final step of public key generation where Y is computed as - - - -D. Eastlake 3rd [Page 3] - - -INTERNET-DRAFT DSA Information in the DNS - - - Y = G**X mod P - - - -3. DSA Signature Information - - The portion of the RDATA area used for US Digital Signature Algorithm - signature information is shown below with fields in the order they - are listed and the contents of each multi-octet field in "big-endian" - network order. - - Field Size - ----- ---- - T 1 octet - R 20 octets - S 20 octets - - First, the data signed must be determined. Then the following steps - are taken, as specified in [FIPS 186-2], where Q, P, G, and Y are as - specified in the public key [Schneier]: - - hash = SHA-1 ( data ) - - Generate a random K such that 0 < K < Q. - - R = ( G**K mod P ) mod Q - - S = ( K**(-1) * (hash + X*R) ) mod Q - - For information on the SHA-1 hash function see [FIPS 180-2] and [RFC - 3174]. - - Since Q is 160 bits long, R and S can not be larger than 20 octets, - which is the space allocated. - - T is copied from the public key. It is not logically necessary in - the SIG but is present so that values of T > 8 can more conveniently - be used as an escape for extended versions of DSA or other algorithms - as later standardized. - - - -4. Performance Considerations - - General signature generation speeds are roughly the same for RSA [RFC - 3110] and DSA. With sufficient pre-computation, signature generation - with DSA is faster than RSA. Key generation is also faster for DSA. - However, signature verification is an order of magnitude slower than - RSA when the RSA public exponent is chosen to be small, as is - recommended for some applications. - - -D. Eastlake 3rd [Page 4] - - -INTERNET-DRAFT DSA Information in the DNS - - - Current DNS implementations are optimized for small transfers, - typically less than 512 bytes including DNS overhead. Larger - transfers will perform correctly and extensions have been - standardized [RFC 2671] to make larger transfers more efficient, it - is still advisable at this time to make reasonable efforts to - minimize the size of RR sets containing keying and/or signature - inforamtion consistent with adequate security. - - - -5. Security Considerations - - 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 essential and - dependent on local policy. - - The key size limitation of a maximum of 1024 bits ( T = 8 ) in the - current DSA standard may limit the security of DSA. For particular - applications, implementors are encouraged to consider the range of - available algorithms and key sizes. - - DSA assumes the ability to frequently generate high quality random - numbers. See [random] for guidance. DSA is designed so that if - biased rather than random numbers are used, high bandwidth covert - channels are possible. See [Schneier] and more recent research. The - leakage of an entire DSA private key in only two DSA signatures has - been demonstrated. DSA provides security only if trusted - implementations, including trusted random number generation, are - used. - - - -6. IANA Considerations - - Allocation of meaning to values of the T parameter that are not - defined herein (i.e., > 8 ) requires an IETF standards actions. It - is intended that values unallocated herein be used to cover future - extensions of the DSS standard. - - - -Copyright and Disclaimer - - Copyright (C) The Internet Society (2005). This document is subject to - the rights, licenses and restrictions contained in BCP 78, and except - as set forth therein, the authors retain all their rights. - - -D. Eastlake 3rd [Page 5] - - -INTERNET-DRAFT DSA Information in the DNS - - - This document and the information contained herein are provided on an - "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS - OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET - ENGINEERING TASK FORCE DISCLAIM 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. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -D. Eastlake 3rd [Page 6] - - -INTERNET-DRAFT DSA Information in the DNS - - -Normative References - - [FIPS 186-2] - U.S. Federal Information Processing Standard: Digital - Signature Standard, 27 January 2000. - - [RFC 4034] - Arends, R., Austein, R., Larson, M., Massey, D., and S. - Rose, "Resource Records for the DNS Security Extensions", RFC 4034, - March 2005. - - - -Informative References - - [RFC 1034] - "Domain names - concepts and facilities", P. - Mockapetris, 11/01/1987. - - [RFC 1035] - "Domain names - implementation and specification", P. - Mockapetris, 11/01/1987. - - [RFC 2671] - "Extension Mechanisms for DNS (EDNS0)", P. Vixie, August - 1999. - - [RFC 3110] - "RSA/SHA-1 SIGs and RSA KEYs in the Domain Name System - (DNS)", D. Eastlake 3rd. May 2001. - - [RFC 3174] - "US Secure Hash Algorithm 1 (SHA1)", D. Eastlake, P. - Jones, September 2001. - - [RFC 4033] - Arends, R., Austein, R., Larson, M., Massey, D., and S. - Rose, "DNS Security Introduction and Requirements", RFC 4033, March - 2005. - - [RFC 4035] - Arends, R., Austein, R., Larson, M., Massey, D., and S. - Rose, "Protocol Modifications for the DNS Security Extensions", RFC - 4035, March 2005. - - [RFC 4086] - Eastlake, D., 3rd, Schiller, J., and S. Crocker, - "Randomness Requirements for Security", BCP 106, RFC 4086, June 2005. - - [Schneier] - "Applied Cryptography Second Edition: protocols, - algorithms, and source code in C" (second edition), Bruce Schneier, - 1996, John Wiley and Sons, ISBN 0-471-11709-9. - - - - - - - - - - -D. Eastlake 3rd [Page 7] - - -INTERNET-DRAFT DSA Information in the DNS - - -Authors Address - - Donald E. Eastlake 3rd - Motorola Labortories - 155 Beaver Street - Milford, MA 01757 USA - - Telephone: +1-508-786-7554(w) - EMail: Donald.Eastlake@motorola.com - - - -Expiration and File Name - - This draft expires in January 2006. - - Its file name is draft-ietf-dnsext-rfc2536bis-dsa-06.txt. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -D. Eastlake 3rd [Page 8] - |