- Initial commit

Runtime/3rdParty/BouncyCastle/crypto/prng/CryptoApiEntropySourceProvider.cs

@@ -0,0 +1,80 @@
+#if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
+#pragma warning disable
+using System;
+using System.Security.Cryptography;
+
+namespace Best.HTTP.SecureProtocol.Org.BouncyCastle.Crypto.Prng
+{
+    public class CryptoApiEntropySourceProvider
+        :   IEntropySourceProvider
+    {
+        private readonly RandomNumberGenerator mRng;
+        private readonly bool mPredictionResistant;
+
+        public CryptoApiEntropySourceProvider()
+            : this(RandomNumberGenerator.Create(), true)
+        {
+        }
+
+        public CryptoApiEntropySourceProvider(RandomNumberGenerator rng, bool isPredictionResistant)
+        {
+            if (rng == null)
+                throw new ArgumentNullException("rng");
+
+            mRng = rng;
+            mPredictionResistant = isPredictionResistant;
+        }
+
+        public IEntropySource Get(int bitsRequired)
+        {
+            return new CryptoApiEntropySource(mRng, mPredictionResistant, bitsRequired);
+        }
+
+        private class CryptoApiEntropySource
+            :   IEntropySource
+        {
+            private readonly RandomNumberGenerator mRng;
+            private readonly bool mPredictionResistant;
+            private readonly int mEntropySize;
+
+            internal CryptoApiEntropySource(RandomNumberGenerator rng, bool predictionResistant, int entropySize)
+            {
+                this.mRng = rng;
+                this.mPredictionResistant = predictionResistant;
+                this.mEntropySize = entropySize;
+            }
+
+            #region IEntropySource Members
+
+            bool IEntropySource.IsPredictionResistant
+            {
+                get { return mPredictionResistant; }
+            }
+
+            byte[] IEntropySource.GetEntropy()
+            {
+                byte[] result = new byte[(mEntropySize + 7) / 8];
+                mRng.GetBytes(result);
+                return result;
+            }
+
+#if NETCOREAPP2_1_OR_GREATER || NETSTANDARD2_1_OR_GREATER || UNITY_2021_2_OR_NEWER
+            int IEntropySource.GetEntropy(Span<byte> output)
+            {
+                int length = (mEntropySize + 7) / 8;
+                mRng.GetBytes(output[..length]);
+                return length;
+            }
+#endif
+
+            int IEntropySource.EntropySize
+            {
+                get { return mEntropySize; }
+            }
+
+            #endregion
+        }
+    }
+}
+#pragma warning restore
+#endif