Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data/System/Data/SqlClient/SqlClientEncryptionAlgorithm.cs

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+//------------------------------------------------------------------------------
+// <copyright file="SqlException.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+// <owner current="true" primary="true">balnee</owner>
+// <owner current="true" primary="false">krishnib</owner>
+//------------------------------------------------------------------------------
+namespace System.Data.SqlClient
+{
+    using System;
+
+    /// <summary>
+    /// Abstract base class for all TCE encryption algorithms. It exposes two functions
+    ///		1. Encrypt - This function is used by SqlClient under the covers to transparently encrypt TCE enabled column data.
+    ///		2. Decrypt - This function is used by SqlClient under the covers to transparently decrypt TCE enabled column data.
+    /// </summary>
+    internal abstract class SqlClientEncryptionAlgorithm
+    {
+        /// <summary>
+        /// Encrypts the plainText with a column encryption key
+        /// </summary>
+        /// <param name="plainText">Plain text value to be encrypted</param>
+        /// <returns></returns>
+        internal abstract byte[] EncryptData(byte[] plainText);
+
+        /// <summary>
+        /// Decrypts the cipherText with a column encryption key
+        /// </summary>
+        /// <param name="cipherText">Ciphertext value to be decrypted</param>
+        /// <returns></returns>
+        internal abstract byte[] DecryptData(byte[] cipherText);
+    }
+}