Merge pull request #3 from fystack/revert

Restore Security Checks Removed in EdDSA CKD Commits

Author: vietddude

crypto/mta/range_proof.go

@@ -141,6 +141,15 @@ func (pf *RangeProofAlice) Verify(ec elliptic.Curve, pk *paillier.PublicKey, NTi
 	if pf.S2.Cmp(q) == -1 {
 		return false
 	}
+	if pf.S.Cmp(one) == 0 {
+		return false
+	}
+	if pf.Z.Cmp(one) == 0 {
+		return false
+	}
+	if pf.S1.Cmp(pf.S2) == 0 {
+		return false
+	}
 
 	// 3.
 	if pf.S1.Cmp(q3) == 1 {

crypto/vss/feldman_vss.go

@@ -93,7 +93,7 @@ func Create(ec elliptic.Curve, threshold int, secret *big.Int, indexes []*big.In
 }
 
 func (share *Share) Verify(ec elliptic.Curve, threshold int, vs Vs) bool {
-	if share.Threshold != threshold || vs == nil {
+	if share.Threshold != threshold || vs == nil || len(vs) != threshold+1 {
 		return false
 	}
 	var err error