1 files changed, 33 insertions, 0 deletions
diff --git a/crypto/src/util/io/compression/Zip.cs b/crypto/src/util/io/compression/Zip.cs
new file mode 100644
index 000000000..f2773d63b
--- /dev/null
+++ b/crypto/src/util/io/compression/Zip.cs
@@ -0,0 +1,33 @@
+using System.IO;
+
+#if NET6_0_OR_GREATER
+using System.IO.Compression;
+#else
+using Org.BouncyCastle.Utilities.Zlib;
+#endif
+
+namespace Org.BouncyCastle.Utilities.IO.Compression
+{
+    internal static class Zip
+    {
+        internal static Stream CompressOutput(Stream stream, int zlibCompressionLevel, bool leaveOpen = false)
+        {
+#if NET6_0_OR_GREATER
+            return new DeflateStream(stream, ZLib.GetCompressionLevel(zlibCompressionLevel), leaveOpen);
+#else
+            return leaveOpen
+                ?   new ZOutputStreamLeaveOpen(stream, zlibCompressionLevel, true)
+                :   new ZOutputStream(stream, zlibCompressionLevel, true);
+#endif
+        }
+
+        internal static Stream DecompressInput(Stream stream)
+        {
+#if NET6_0_OR_GREATER
+            return new DeflateStream(stream, CompressionMode.Decompress, leaveOpen: false);
+#else
+            return new ZInputStream(stream, true);
+#endif
+        }
+    }
+}