MAYO in openssl-oqs

[hugomayer57]

Hello,

We are working with the MAYO1 post-quantum algorithm using OpenSSL-OQS and have a scenario where we only have access to the private key. Our goal is to understand whether it would be straightforward to derive the corresponding public key from the private key for MAYO1 for recreate the key pair, similar to how it can be done with other algorithms (such as ED448) using OpenSSL's EVP_PKEY_new_raw_private_key() function.

Specifically, for ED448, we can use:

EVP_PKEY *key = EVP_PKEY_new_raw_private_key(EVP_PKEY_ED448, NULL, private_key, len_key);

This function creates the private key structure and internally also handles the generation of the corresponding public key. We are wondering if there is a similar solution available within OpenSSL-OQS for MAYO1. Is there a method or function in OpenSSL-OQS that would allow us to generate the MAYO1 public key from just the private key in a similar way, or is this something that OpenSSL-OQS does not support natively?

Additionally, if deriving the public key directly from the private key is not feasible, is there any alternative approach within the OpenSSL-OQS framework to handle this scenario?

[SWilson4]

Hi @hugomayer57, thanks for the question and sorry it has taken so long for us to get back to you. In general, oqs-provider doesn't support deriving (raw) public keys from (raw) private keys, as this is not a standard API in liboqs, and oqs-provider does not (currently) implement algorithm-specific code. See a related issue for ML-KEM: #637. However, public keys are included by default in private key structures.