Does Apple secure enclave support rfc6979 with P256 curve? This RFC defines a deterministic ecdsa with a deterministic k value.

THATS LINK OF THE RFC https://www.rfc-editor.org/rfc/rfc6979

I looked everywhere in their documentation but couldn't find a mention of such usage

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    $\begingroup$ The question is also posted there. It got no answer. No rationale for using deterministic ECDSA is given in either question, and compatibility with a verifier can't be a valid reason, since the verifier can't tell if ECDSA or deterministic ECDSA was used. If I had to place a bet at even odds, make it: no, Apple secure enclave does not support RFC6979, because there is little demand for it. $\endgroup$
    – fgrieu
    Jun 5, 2023 at 16:05
  • $\begingroup$ @fgrieu the reason why I'm asking if deterministic ecdsa is used or not is because I want to use the deterministic signature s on P256 curve as a source of entropy to generate a new pair of keys on secp256k1 curve. $\endgroup$
    – mathcrypto
    Jun 5, 2023 at 19:29
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    $\begingroup$ For a "source of entropy", we need standard (non-deterministic) ECDSA. But I think I get the idea: with a little extra work that can be done publicly, one can turn an RFC6979 signing device and it's corresponding public key into something that, given a public diversifier as message, reproducibly produce an ECDSA public key which corresponding private key remains secret, but is computable with the device's private key and the diversifier. And the signature proposed by the device doubles as a digital certificate. $\endgroup$
    – fgrieu
    Jun 6, 2023 at 5:35
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    $\begingroup$ @fgrieu-onstrike IETF has RFC-8937 that sounds similar, but for an entirely different purpose. $\endgroup$
    – DannyNiu
    Jun 8, 2023 at 13:07
  • $\begingroup$ @mathcrypto Not necessarily. As I said in the comment - [it's] for an entirely different purpose. $\endgroup$
    – DannyNiu
    Jun 12, 2023 at 12:45


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