Reject small-order Ed25519 public keys in Validate - #36
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…#1352) ed25519PublicKey::Validate checked public-key canonicality but did not reject small-order points. That left the identity-point case from #1352 accepted by Validate even though it is not a valid Ed25519 public key for strict validation. Wire the existing HasSmallOrder helper into ed25519PublicKey::Validate at level >= 2. Canonical encoding checks still run at all validation levels; small-order rejection is part of the stricter validation path. validat7.cpp covers the validation-level boundary: the identity key is accepted at level 0, rejected at level 2, and a fresh keypair remains accepted at level 2. validat9.cpp keeps the non-canonical public-key test scoped to canonicality by running it at level 1. Its baseline pk_id and pk_pminus1 values are also small-order points, so level 2 would test two properties at once.
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Summary
This closes the remaining small-order public key part of upstream issue
weidai11/cryptopp#1352.ed25519PublicKey::Validatenow rejects small-order Ed25519 public keys at validation level 2 and above. The existing canonical encoding check still runs at all validation levels, so level 0 behaviour is unchanged.What changed
ed25519PublicKey::Validatenow uses the existingHasSmallOrderhelper at level 2 and above.validat7.cppadds coverage for the level boundary: identity accepted at level 0, identity rejected at level 2, fresh keypair accepted at level 2.validat9.cppnow runs the non-canonical public-key test at level 1 so it stays scoped to canonicality.This follows upstream commit
weidai11/cryptopp@4775a166.