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Security Transport Layer Security§ ML-DSA FIPS204 This memo specifies how the post-quantum signature scheme ML-DSA (FIPS 204) is used for authentication in TLS 1.3. About This Document The latest revision of this draft can be found at . Status information for this document may be found at . Discussion of this document takes place on the Transport Layer Security Working Group mailing list (), which is archived at . Subscribe at . Source for this draft and an issue tracker can be found at .

Introduction ML-DSA is a post-quantum module-lattice based digital signature algorothm standardised by NIST in . This memo specifies how ML-DSA can be negotiated for authentication in TLS 1.3 via the "signature_algorithms" and "signature_algorithms_cert" extensions.

Conventions and Definitions 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 when, and only when, they appear in all capitals, as shown here.

ML-DSA SignatureSchemes Types As defined in , the SignatureScheme namespace is used for the negotiation of signature scheme for authentication via the "signature_algorithms" and "signature_algorithms_cert" extensions. This document adds three new SignatureSchemes types for the three ML-DSA parameter sets as follows. These correspond to ML-DSA-44, ML-DSA-65, and ML-DSA-87 defined in respectively. Note that these are different from the HashML-DSA pre-hashed variantsadefined in Section 5.4 of . The signature MUST be computed and verified as specified in . The context parameter defined in Algorithm 2 and 3 MUST be the empty string. The corresponding end-entity certificate when negotiated MUST use id-ML-DSA-44, id-ML-DSA-65, id-ML-DSA-87 respectively as defined in . The schemes defined in this document MUST NOT be used in TLS 1.2 . A peer that receives ServerKeyExchange or CertificateVerify message in a TLS 1.2 connection with schemes defined in this document MUST abort the connection with an illegal_parameter alert.

Security Considerations TODO Security

IANA Considerations This document requests new entries to the TLS SignatureScheme registry, according to the procedures in .

Value	Description	Recommended	Reference
0x0904 (please)	mldsa44	N	This document.
0x0905 (please)	mldsa65	N	This document.
0x0906 (please)	mldsa87	N	This document.

References Normative References National Institute of Standards and Technology (U.S.) In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. Informative References This document specifies Version 1.2 of the Transport Layer Security (TLS) protocol. The TLS protocol provides communications security over the Internet. The protocol allows client/server applications to communicate in a way that is designed to prevent eavesdropping, tampering, or message forgery. [STANDARDS-TRACK] This document specifies version 1.3 of the Transport Layer Security (TLS) protocol. TLS allows client/server applications to communicate over the Internet in a way that is designed to prevent eavesdropping, tampering, and message forgery. This document updates RFCs 5705 and 6066, and obsoletes RFCs 5077, 5246, and 6961. This document also specifies new requirements for TLS 1.2 implementations. Venafi sn3rd This document updates the changes to TLS and DTLS IANA registries made in RFC 8447. It adds a new value "D" for discouraged to the Recommended column of the selected TLS registries and adds a "Comments" column to all active registries that do not already have a "Comments" column. This document updates the following RFCs: 3749, 5077, 4680, 5246, 5705, 5878, 6520, 7301, and 8447. AWS AWS sn3rd Cloudflare Digital signatures are used within X.509 certificates, Certificate Revocation Lists (CRLs), and to sign messages. This document describes the conventions for using FIPS 204, the Module-Lattice- Based Digital Signature Algorithm (ML-DSA) in Internet X.509 certificates and certificate revocation lists. The conventions for the associated signatures, subject public keys, and private key are also described.

Acknowledgments Thanks to Alicja Kario, John Mattsson, and Rebecca Guthrie for their review and feedback.