Independent submission M. Richardson Internet-Draft SSW Expires: February 8, 2003 August 10, 2002 A method for storing IPsec keying material in DNS. draft-richardson-ipsec-rr-00.txt Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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 as "work in progress." The list of current Internet-Drafts can be accessed at http:// www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on February 8, 2003. Copyright Notice Copyright (C) The Internet Society (2002). All Rights Reserved. Abstract This document describes a new resource record for DNS. This record may be used to store public keys for use in IPsec systems. This record replaces the functionality of the sub-type #1 of the KEY Resource Record, which has been proposed to be obsoleted by [1]. Richardson Expires February 8, 2003 [Page 1] Internet-Draft ipsecrr August 2002 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Storage formats . . . . . . . . . . . . . . . . . . . . . . . 4 2.1 IPSECKEY RDATA format . . . . . . . . . . . . . . . . . . . . 4 2.2 priority of this entry . . . . . . . . . . . . . . . . . . . . 5 2.3 IPv4 address of the gateway . . . . . . . . . . . . . . . . . 5 2.4 IPv6 address of the gateway . . . . . . . . . . . . . . . . . 5 2.5 FQDN of the gateway . . . . . . . . . . . . . . . . . . . . . 5 2.6 RSA public of the gateway . . . . . . . . . . . . . . . . . . 5 3. Presentation formats . . . . . . . . . . . . . . . . . . . . . 7 3.1 File Representation of IPSECKEY RRs . . . . . . . . . . . . . 7 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9 Normative references . . . . . . . . . . . . . . . . . . . . . 10 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 10 Full Copyright Statement . . . . . . . . . . . . . . . . . . . 11 1. Introduction 1.1 Overview A 2. Storage formats The IPSECKEY resource record (RR) is used to document a key that is associated with a Domain Name System (DNS) name. It will be a public key as only public keys are stored in the DNS. This can be the public key of a host, network, or application (in the case of per- port keying). An IPSECKEY RR is, like any other RR, authenticated by a SIG RR. Security aware DNS implementations MUST be designed to handle at least two simultaneously valid keys of the same type associated with a name. The type number for the IPSECKEY RR is TBD. 2.1 IPSECKEY RDATA format The RDATA for an IPSECKEY RR consists of a series of type/length/ Richardson Expires February 8, 2003 [Page 2] Internet-Draft ipsecrr August 2002 value and type/value records. The canonical ordering of the fields is by increasing ordinal values of the type field. A type may not occur more than once. Each field consistsa reserved field, a field type octet, and a length of that field. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | field type | reserved | length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | / / data / / / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-| (XXX - Do we really need a 16-bit length? 8-bits will not suffice for public keys. Or should we for for 11 or 12 bits with a 4 or 5 bit field type?) The meaning of the IPSECKEY RR field type are described in the following sections. The length field is the number of the octets in this field type, and includes the size of the common header. Definitions for field types: 0 no more fields 1 priority of this entry 2 IPv4 address of the gateway for this host 3 IPv6 address of the gateway for this host 4 FQDN of the gateway for this host 5 RSA public key for the gateway 2.2 priority of this entry This is a 16-bit preference for this record. This is interpreted in a similar way to the PREFERENCE field described in section 3.3.9 of [3]. 2.3 IPv4 address of the gateway Richardson Expires February 8, 2003 [Page 3] Internet-Draft ipsecrr August 2002 The data portion is an IPv4 address as described in section 3.4.1 of [3]. This is a 32-bit number in network byte order. The presence of this value indicates the end point for an IPsec tunnel. This record is mutually exclusive with types 3 and 4. 2.4 IPv6 address of the gateway The data portion is an IPv6 address as described in section 3.2 of [4]. This is a 128-bit number in network byte order. The presence of this value indicates the end point for an IPsec tunnel. This record is mutually exclusive with types 2 and 4. 2.5 FQDN of the gateway The data portion is a %lt;domain-name%gt; encoded as described in section 3.3 of [4]. The presence of this value indicates the end point for an IPsec tunnel. This record is mutually exclusive with types 2 and 3. 2.6 RSA public of the gateway The data portion of the field contains an RSA public key, encoded as described in secion 2 of [6], and repeated here: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | pub exp length| public key exponent / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | / +- modulus / | / +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-/ RFC2065 limited the exponent and modulus to 2552 bits in length, and RFC3110 to 4096 bits. No such limit is specified here for the purposes of encoding and decoding. The length in octets of the public exponent length is represented as one octet if it is in the range of 1 to 255 and by a zero octet followed by a two octet unsigned length if it is longer than 255 bytes. The public key modulus field is a multiprecision unsigned integer. The length of the modulus can be determined from the RDLENGTH and the preceding RDATA fields including the exponent. Leading zero bytes are prohibited in the exponent and modulus. Richardson Expires February 8, 2003 [Page 4] Internet-Draft ipsecrr August 2002 3. Presentation formats 3.1 File Representation of IPSECKEY RRs IPSECKEY RRs may appear as lines in a zone data master file. The preference and at least one key are mandatory. As the IPv4, IPv6 and FQDN references to the gateway are mutually exclusive, they can share a position. If no gateway is to be indicated, then the special tokens of either "-" or "none" may be used. 38.46.139.192.in-addr.arpa. 7200 IN IPSECKEY ( 10 192.139.46.38 RSA: AQOrXJxB56Q28iOO43Va36elIFFKc/QB2orIeL94BdC5X4idFQZjSpsZ Th48wKVXUE9xjwUkwR4R4/+1vjNN7KFp9fcqa2OxgjsoGqCn+3OPR8La 9uyvZg0OBuSTj3qkbh/2HacAUJ7vqvjQ3W8Wj6sMXtTueR8NNcdSzJh1 49ch3zqfiXrxxna8+8UEDQaRR9KOPiSvXb2KjnuDan6hDKOT4qTZRRRC MWwnNQ9zPIMNbLBp0rNcZ+ZGFg2ckWtWh5yhv1iXYLV2vmd9DB6d4Dv8 cW7scc3rPmDXpYR6APqPBRHlcbenfHCt+oCkEWse8OQhMM56KODIVQq3 fejrfi1H ) 4. IANA Considerations Additional field types must be assigned by IANA. A document must detail the format of the field. 5. Acknowledgments People who pushed me to write this. Normative references [1] Massey, D. and S. Rose, "Limiting the Scope of the KEY Resource Record", ID internet-draft (draft-ietf-dnsext-restrict-key-for- dnssec-02) (normative), March 2002. [2] Mockapetris, P., "Domain names - concepts and facilities", STD 13, RFC 1034, November 1987. [3] Mockapetris, P., "Domain names - implementation and specification", STD 13, RFC 1035, November 1987. [4] Thomson, S. and C. Huitema, "DNS Extensions to support IP version 6", RFC 1886, December 1995. [5] Eastlake, D., "Domain Name System Security Extensions", RFC 2535, March 1999. [6] Eastlake, D., "RSA/SHA-1 SIGs and RSA KEYs in the Domain Name Richardson Expires February 8, 2003 [Page 5] Internet-Draft ipsecrr August 2002 System (DNS)", RFC 3110, May 2001. Author's Address Michael C. Richardson Sandelman Software Works 470 Dawson Avenue Ottawa, ON K1Z 5V7 CA EMail: mcr@sandelman.ottawa.on.ca URI: http://www.sandelman.ottawa.on.ca/ Full Copyright Statement Copyright (C) The Internet Society (2002). All Rights Reserved. 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