Imported Upstream version 5.18.0.142

Former-commit-id: 7467d4b717762eeaf652d77f1486dd11ffb1ff1f

mcs/class/corlib/corefx/Interop.GetRandomBytes.Mono.cs

@@ -0,0 +1,36 @@
+using System;
+using System.Diagnostics;
+using System.Security.Cryptography;
+using System.Runtime.InteropServices;
+
+internal partial class Interop
+{
+	static class MonoGetRandomBytesFallback
+	{
+		static object _rngAccess = new object ();
+		static RNGCryptoServiceProvider _rng;
+
+		internal static void GetRandomBytes (byte[] buffer)
+		{
+			lock (_rngAccess) {
+				if (_rng == null)
+					_rng = new RNGCryptoServiceProvider ();
+				_rng.GetBytes (buffer);
+			}
+		}
+
+		internal static unsafe void GetRandomBytes (byte* buffer, int length)
+		{
+			lock (_rngAccess) {
+				if (_rng == null)
+					_rng = new RNGCryptoServiceProvider ();
+				_rng.GetBytes (buffer, (IntPtr)length);
+			}
+		}
+	}
+
+	internal static unsafe void GetRandomBytes (byte* buffer, int length)
+	{
+		MonoGetRandomBytesFallback.GetRandomBytes (buffer, length);
+	}
+}