Implement scalar arithmetic via Barrett reduction #56
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| /// Parses the given byte array as hashed message. | ||
| /// | ||
| /// Subtracts the modulus when the byte array is larger than the modulus. | ||
| pub fn from_hash(bytes: [u8; 32]) -> Self { |
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I would expect a from_hash method to accept a Digest instance. How about naming it from_bytes_mod_order instead?
| pub fn from_hash(bytes: [u8; 32]) -> Self { | |
| pub fn from_bytes_mod_order(bytes: [u8; 32]) -> Self { |
You could then add a from_hash method that does accept a Digest instance (gated on a digest feature)
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I'm not sure what the right name is. Thinking generically, this is tied to "Let z be the leftmost bits of
, where
is the bit length of the group order n.", which for p256 is just reduction but for other curves can involve right-shifts. So I'd like a method and name that captures this requirement. Ideas/prior art?
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I think from_hash is fine if the argument is a Digest instance. There's a bit of a rationale for why e.g. signature::DigestSigner takes one (as opposed to a byte array) here:
https://docs.rs/signature/1.1.0/signature/trait.DigestSigner.html#notes
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Sure, I'll follow along if/when #76 is merged 👍
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To make #54 more concrete.