Internet Engineering Task Force SC. Chin, Ed. Internet-Draft D3 Global Inc Intended status: Standards Track 11 August 2025 Expires: 12 February 2026 DNS to Web3 Wallet Mapping draft-chins-dnsop-web3-wallet-mapping-03 Abstract This document proposes an implementation standard for mapping wallets to domain names using the new WALLET RRType, allowing for TXT record fallback while the WALLET RRType propagates through DNS providers. The goal is to provide a secure and scalable and unbiased way to associate wallets with domain names, enabling seamless lookup as well as suggesting required authentication mechanism. The proposal relies on DNSSEC or security successors to ensure trust and security. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on 12 February 2026. Copyright Notice Copyright (c) 2025 IETF Trust and the persons identified as the document authors. All rights reserved. Chin Expires 12 February 2026 [Page 1] Internet-Draft Abbreviated Title August 2025 This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. Domain to Wallet Mapping . . . . . . . . . . . . . . . . . . 3 3.1. Record Format . . . . . . . . . . . . . . . . . . . . . . 3 3.2. Grammar for the record in EBNF format . . . . . . . . . . 4 3.3. Example . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.4. TXT Record Example . . . . . . . . . . . . . . . . . . . 5 3.5. Multiple Records . . . . . . . . . . . . . . . . . . . . 5 3.6. Implementation . . . . . . . . . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . 6 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 6 6.1. Normative References . . . . . . . . . . . . . . . . . . 6 6.2. Informational References . . . . . . . . . . . . . . . . 7 Appendix A. Example code . . . . . . . . . . . . . . . . . . . . 7 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 8 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction There is fragmentation in the mapping of Web3 Wallets to Domain Names [RFC1034]. This document puts forth an implementation standard to map Web3 Wallet addresses to Domain Names, as well as investigates the associated security and technical concerns. As the use of digital wallets and online services grows, the need for a standardized way to lookup wallet addresses in an human readable format becomes increasingly important. This proposal aims to provide a solution that is easy to implement, scalable, unbiased, standardized and secure. The proposed notational implementation involves using the DNS WALLET RRtype [WALLET-IANA-RRTYPE] to map a domain name on the Global DNS system to wallet address information. The WALLET record will contain a object that maps the wallet address to a registered Namespace Chin Expires 12 February 2026 [Page 2] Internet-Draft Abbreviated Title August 2025 [CHAIN-AGNOSTIC-NAMESPACES] and the registered coin type token [SLIP-0044] or [CAIP-2]. This implementation will handle multiple wallet addresses and chains, defaults, as well as defining a heirarchy to deterministicly be able to find the appropriate wallet address. It is assumed that the record will be part of a DNSSEC [RFC4033] [RFC9364] signed zonefile or its security successors, and that users of this service will verify the signatures to ensure that the record has been returned without alteration in flight. This implementation proposal is evolutionary to the the description in [WALLET-IANA-RRTYPE] because it defines standards for coin names, defaults, and conditions for rejection, in order to have consistant usages. We also propose a fallback TXT record "_w3addr" which will be a backup for the WALLET RRtype and CAN duplicate the WALLET RRtype entries. This is intended to be a temporary measure while DNS Provider's UIs support this RRType [RFC3597]. 1.1. Requirements Language 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 BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 2. Terminology This document will refer to Domain Name terminology [RFC9499]. 3. Domain to Wallet Mapping 3.1. Record Format The WALLET or TXT record SHALL have the following format: @ IN WALLET "namespace:reference:address1" @ IN TXT "namespace:reference:address1" @ is the address IN is the class of the record WALLET / TXT is the type of the record Chin Expires 12 February 2026 [Page 3] Internet-Draft Abbreviated Title August 2025 namespace:reference:address1 is the value of the record 3.2. Grammar for the record in EBNF format item = namespace ":" (coin_name | reference) ":" address namespace = (letter | digit | "-"){3,8} coin_name = (letter | digit | "_"){1,32} address = ( letter | digit | "-" | "." | "%" ){1,128} letter = "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" | "J" | "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" | "S" | "T" | "U" | "V" | "W" | "X" | "Y" | "Z" | "a" | "b" | "c" | "d" | "e" | "f" | "g" | "h" | "i" | "j" | "k" | "l" | "m" | "n" | "o" | "p" | "q" | "r" | "s" | "t" | "u" | "v" | "w" | "x" | "y" | "z" digit = "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" item represents a namespace-reference-address tuple namespace covers a class of similar blockchains such as "Solana" or "eip155" specified by Chain Agnostic Namespaces [CHAIN-AGNOSTIC-NAMESPACES]. This is NOT case sensitive. coin_name represents the Symbol of a Coin Type represented in [SLIP-0044]. This is NOT case sensitive. reference a way to identify a blockchain within a namespace. As an example this would be chain ID within eip155 ecosystem as referenced by [CAIP-2]. This is NOT case sensitive. address represents the public wallet address associated with a coin (e.g., "0xabcdefg", "0x12345", etc). This CAN be case sensitive as required by the wallet addressing scheme This grammar can be used to parse the input string and extract the chain identifier and addresses. Chin Expires 12 February 2026 [Page 4] Internet-Draft Abbreviated Title August 2025 3.3. Example Suppose a user wants to map their wallet with the public keys to the domain "example.com" using the registered coin type tokens BTC, SOL and and Ethereum mainnet chain id. The WALLET record in the zone would be: @ IN WALLET "bip122:BTC:0x1234567890abcd" @ IN WALLET "solana:SOL:0x567890123456789" @ IN WALLET "eip155:1:0x987654321098765" 3.4. TXT Record Example Suppose a user wants to map their wallet with the public keys to the domain "example.com" using the registered coin type tokens BTC, SOL and Ethereum mainnet chain id using a TXT record. The TXT record in the zone would be: _waddr IN TXT "bip122:BTC:0x1234567890abcd" _waddr IN TXT "solana:SOL:0x567890123456789" _waddr IN TXT "eip155:1:0x987654321098765" 3.5. Multiple Records To support multiple coins, multiple coin:address pairs will each be represented by their own WALLET record. There is no guarantees on ordering the records so overlapping records MAY be ordered at the resolver's discretion. In the event of duplicate coin types it is RECOMMENDED that multiple records be returned deduplicated for identical addresses. 3.6. Implementation Wallet resolver implementations of this RFC SHALL: 1. Support the creation and retrieval of WALLET records for any given level of the DNS system. 2. Validate the records as being properly signed by DNSSEC or its successors. 3. Provide the wallet's address for a human readable domain name. 4. Provide an authoritative NXADDR if no address can be found. Chin Expires 12 February 2026 [Page 5] Internet-Draft Abbreviated Title August 2025 4. Security Considerations To ensure the security of the mapping, the following measures will be taken: 1. The WALLET RRtype record SHALL BE stored in a secure location, such as a DNSSEC-signed zone. 2. The implementation SHALL validate the DNSSEC record or its IETF approved successors. 3. The wallet record SHALL be protected from replay attacks via DNSSEC time invalidation (or approved successors). The WALLET RRtype might not be available throughout entire end to end DNS infrastructure. In the event that DNSSEC is not supported end to end, a wallet resolver MUST indicate that the wallet address is informational only and CANNOT be trusted. If the source of the DNS zone is compromised, the wallet address mapping is compromised. It is imperative that this not occur for both DNS stability, as well as wallet mapping Notationaly using DNS. 5. IANA Considerations This proposal does not require IANA changes. 6. References 6.1. Normative References [RFC1034] Mockapetris, P., "Domain names - concepts and facilities", STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC3597] Gustafsson, A., "Handling of Unknown DNS Resource Record (RR) Types", RFC 3597, DOI 10.17487/RFC3597, September 2003, . [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S. Rose, "DNS Security Introduction and Requirements", RFC 4033, DOI 10.17487/RFC4033, March 2005, . Chin Expires 12 February 2026 [Page 6] Internet-Draft Abbreviated Title August 2025 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC9364] Hoffman, P., "DNS Security Extensions (DNSSEC)", BCP 237, RFC 9364, DOI 10.17487/RFC9364, February 2023, . [RFC9499] Hoffman, P. and K. Fujiwara, "DNS Terminology", BCP 219, RFC 9499, DOI 10.17487/RFC9499, March 2024, . 6.2. Informational References [SLIP-0044] "Registered coin types for BIP-0044", . [CAIP-2] Warta, S., , Gomes, P., and A. Herzog, "CAIP-2: Blockchain ID Specification", December 2019, . [CHAIN-AGNOSTIC-NAMESPACES] "Chain Agnostic Namespaces", . [WALLET-IANA-RRTYPE] "Wallet Completed Template", 2024-06-24, . Appendix A. Example code Here is an example of how to create and retrieve a WALLET records using the domain name: import dns.resolver.wallet # Retrieve the WALLET record record = dns.resolveWallet("example.com", "BTC") print(record.value) # Output: "0x1234567890abcdef" xs Chin Expires 12 February 2026 [Page 7] Internet-Draft Abbreviated Title August 2025 Contributors Thanks to all of the contributors for contributions to security and clarity. Yevhenii Andrushchak Email: yevhenii@d3.com Kai Sung Email: kai@d3.com Acknowledgements Reviewed by: Jothan Frakes Email: jothan@frakes.com Author's Address Shay Chin (editor) D3 Global Inc Email: shay@d3.com Chin Expires 12 February 2026 [Page 8]