The functions are currently unused, but Stef pointed out that the xeddsa and vxeddsa verify strictness check had a return value incompatible with the verify function's return value, causing a strictness check failure to be interpreted as a signature verification success.

This change also removes some other old/vestigial code.

Author: Trolldemorted

curve25519-dotnet/csharp/fe_isreduced.cs

@@ -0,0 +1,23 @@
+using org.whispersystems.curve25519.csharp;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace curve25519_dotnet.csharp
+{
+    public class Fe_isreduced
+    {
+        public static bool fe_isreduced(byte[] curve25519_pubkey)
+        {
+            int[] fe = new int[10];
+            byte[] strict = new byte[32];
+
+            Fe_frombytes.fe_frombytes(fe, curve25519_pubkey);
+            if (Crypto_verify_32.crypto_verify_32(strict, curve25519_pubkey) != 0)
+                return false;
+            return true;
+        }
+    }
+}