Fix ed25519 key type in ca_util

[rculpepper]

This PR is to address the error described in issue #26089 with ed25519 keys

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[victorr]

👍

Is there maybe a unit test we can augment to cover this case?

[stevendpclark]

Unit test would be welcome, there's also a similar error within GetPrivateKeyTypeFromPublicKey.

Would you mind addressing that one as well as part of this? Also what are your thoughts on just adding both the pointer and non-pointer types to all the case statements?

[rculpepper]

Also what are your thoughts on just adding both the pointer and non-pointer types to all the case statements?

I don't have a problem with it, but I don't know how useful it would be. I don't see anywhere that we expect an ed25519 key to be a pointer (except the case here)

[stevendpclark]

Suggested change

	pki: Fix error in cross-signing using ed25519 keys
	secrets/pki: Fix error in cross-signing using ed25519 keys

[stevendpclark]

I don't have a problem with it, but I don't know how useful it would be. I don't see anywhere that we expect an ed25519 key to be a pointer (except the case here)

Fair, lets not bother for now.