Here's what I remember from the original discussion of h= and k= in
the key record.
First, part of the idea was to have them both there, to make things
parallel: "This key is used for this crypto suite."
[...]
I'm neutral on either keeping or removing this one. It seems to me an RSA key
is invalid input to any other crypto mechanism, so those functions will do the
validation implicitly.
Since "h=" doesn't have the same benefit, I'd rather keep it.
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