+hazel-networking

1 files changed, 36 insertions, 0 deletions

diff --git a/Tools/Hazel-Networking/Hazel/Crypto/SpanCryptoExtensions.cs b/Tools/Hazel-Networking/Hazel/Crypto/SpanCryptoExtensions.cs
new file mode 100644
index 0000000..03164ec
--- /dev/null
+++ b/Tools/Hazel-Networking/Hazel/Crypto/SpanCryptoExtensions.cs
@@ -0,0 +1,36 @@
+using System;
+using System.Security.Cryptography;
+
+namespace Hazel.Crypto
+{
+    public static class SpanCryptoExtensions
+    {
+        /// <summary>
+        /// Clear a span's contents to zero
+        /// </summary>
+        public static void SecureClear(this ByteSpan span)
+        {
+            if (span.Length > 0)
+            {
+                Array.Clear(span.GetUnderlyingArray(), span.Offset, span.Length);
+            }
+        }
+
+        /// <summary>
+        /// Fill a byte span with random data
+        /// </summary>
+        /// <param name="random">Entropy source</param>
+        public static void FillWithRandom(this ByteSpan span, RandomNumberGenerator random)
+        {
+            if (span.Offset == 0 && span.Length == span.GetUnderlyingArray().Length)
+            {
+                random.GetBytes(span.GetUnderlyingArray());
+                return;
+            }
+
+            byte[] temp = new byte[span.Length];
+            random.GetBytes(temp);
+            new ByteSpan(temp).CopyTo(span);
+        }
+    }
+}