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zeekayandHanzo Dev
3685ebea4c
Both protocol adapters shipped a Verify that returned false unconditionally — cggmp21 with "For now, return false", frost with "doesn't support ECDSA". That is not a safe default dressed up as one. A verifier that always fails is indistinguishable from a verifier that works and was handed a bad signature, so a caller using it as a signing-path health check sees a permanent, unexplained failure, and a caller treating "unsupported" as skippable gets no verification at all. Both now verify. FROST is Schnorr rather than ECDSA, but its group key is still a secp256k1 point and *ecdsa.PublicKey is only how this package's interface carries one, so the point is recovered and handed to the FROST verifier. pkg/protocol/curvekey.go holds the conversion both adapters need, replacing two hand-rolled decompressions (a Tonelli-Shanks square root in cggmp21, a separate helper in frost). CurvePoint goes the other way, and it validates rather than assumes: an (X, Y) that is not on the curve is REJECTED, not silently corrected. Compression keeps only the parity of Y, so a conversion that trusts X and parity alone will happily turn an inconsistent key into a valid point and then verify signatures against a key the caller never named. X=1 is a real X coordinate on secp256k1, which is how the test that found this was written. X is left-padded with FillBytes; big.Int drops leading zeros, so about one key in 256 would otherwise encode short and fail to convert at all. Bumps luxfi/threshold to v1.12.5 for pkg/quorum. Co-authored-by: Hanzo Dev <[email protected]>