1 files changed, 23 insertions, 0 deletions
diff --git a/crypto/src/crypto/IStreamCalculator.cs b/crypto/src/crypto/IStreamCalculator.cs
new file mode 100644
index 000000000..19a542845
--- /dev/null
+++ b/crypto/src/crypto/IStreamCalculator.cs
@@ -0,0 +1,23 @@
+using System;
+using System.IO;
+
+namespace Org.BouncyCastle.Crypto
+{
+    /// <summary>
+    /// Base interface for cryptographic operations such as Hashes, MACs, and Signatures which reduce a stream of data
+    /// to a single value.
+    /// </summary>
+    public interface IStreamCalculator
+    {
+        /// <summary>Return a "sink" stream which only exists to update the implementing object.</summary>
+        /// <returns>A stream to write to in order to update the implementing object.</returns>
+        Stream Stream { get; }
+
+        /// <summary>
+        /// Return the result of processing the stream. This value is only available once the stream
+        /// has been closed.
+        /// </summary>
+        /// <returns>The result of processing the stream.</returns>
+        Object GetResult();
+    }
+}