wip frost signing

Author: aakselrod

btcec/schnorr/threshold/frost/errors.go

@@ -0,0 +1,42 @@
+package frost
+
+type ContributionType uint8
+
+const (
+	ContributionTypePubNonce ContributionType = iota
+	ContributionTypeAggNonce
+	ContributionTypeAggOtherNonce
+	ContributionTypePSig
+)
+
+func (c ContributionType) String() string {
+	switch c {
+	case ContributionTypePubNonce:
+		return "pubnonce"
+
+	case ContributionTypeAggOtherNonce:
+		return "aggothernonce"
+
+	case ContributionTypeAggNonce:
+		return "aggnonce"
+
+	case ContributionTypePSig:
+		return "psig"
+
+	default:
+		return "unknown"
+	}
+}
+
+type ErrInvalidContribution struct {
+	// SignerIndex is the signer index when the error is due to a known
+	// signer, or -1 when there's an error due to an aggregated value.
+	SignerIndex int
+
+	// ContributionType is the type of invalid contribution.
+	ContributionType
+}
+
+func (e ErrInvalidContribution) Error() string {
+	return "Invalid contribution"
+}