[Acme] 回复：Proof-of-Possession for HQC KEM

[皮皮猪 <[e-mail]>]

Hi Alexandre,


This is an interesting direction, especially as some still favor keeping the CSR workflow. I also think it is a complementary approach that can coexist with draft-ietf-acme-pop and give the community more options for integrating KEM certificates into ACME.


Happy to discuss further.


Best regards,
Feng Geng


         原始邮件
         
       
发件人：Alexandre Augusto <[e-mail]&gt;
发件时间：2026年9月9日 09:48
收件人：acme <[e-mail]&gt;
抄送：Mukul Kulkarni <[e-mail]&gt;, Slim Bettaieb <[e-mail]&gt;, Marco Palumbi <[e-mail]&gt;
主题：[Acme] Proof-of-Possession for HQC KEM



Dear ACME community,

In collaboration with Slim Bettaieb, Mukul Kulkarni, and Marco Palumbi at TII/UAE, we would like to share that we want to propose an I-D for an approach which we call "HQC-PoP". Such an approach is based on the VOLEith paradigm and allows us to build a Proof-of-Possession of the secret key for HQC. It has the following features:

1. Compatibility with CSR-like enrollment processes, easing integration into the ACME protocol
2. No need for new challenges or new messages to the ACME protocol, it only requires CSR processing (validate the proof)
3. Shorter proofs when compared to similar approaches based on non-interactive proofs for lattice-based cryptography
4. Compatibility with the upcoming HQC NIST standard, since our approach does not require any modification to key generation algorithms, we simply consume the generated key as input.

In short terms, the key holder or an ACME client could compute a proof with ZKP <- HQCPoP.prove(sk, H(CSR)), where H is a hash function over the CSR contents. This ZKP, in the non-interactive setting, can serve the purpose of a signature. The client sends this CSR to the server; finally, the server computes HQCPoP.verify(pk, H(CSR). In the end, the client would download a KEM certificate (HQC public key) signed by the CA.

Our work will be available on preprint soon. We will be more than happy to contribute to the WG if the community sees this proposal valuable.


Best regards,
--
Alexandre Augusto Giron
Federal University of Technology - Parana (UTFPR)