Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data/System/Data/SqlClient/SqlAes256CbcAlgorithm.cs

@@ -0,0 +1,65 @@
+//------------------------------------------------------------------------------
+// <copyright file="SqlAes256CbcAlgorithm.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;
+    using System.Collections.Generic;
+    using System.Data.SqlClient;
+    using System.Diagnostics;
+    using System.IO;
+    using System.Runtime.CompilerServices;
+    using System.Security.Cryptography;
+
+    /// <summary>
+    /// This class implements AES_256_CBC algorithm.
+    /// </summary>
+    internal class SqlAes256CbcAlgorithm : SqlAeadAes256CbcHmac256Algorithm
+    {
+        /// <summary>
+        /// Algorithm Name
+        /// </summary>
+        internal new const string AlgorithmName = @"AES_256_CBC";
+
+        /// <summary>
+        /// Initializes a new instance of SqlAes256CbcAlgorithm algorithm with a given key and encryption type
+        /// </summary>
+        /// <param name="encryptionKey">
+        /// Root encryption key from which three other keys will be derived
+        /// </param>
+        /// <param name="encryptionType">Encryption Type, accepted values are Deterministic and Randomized. 
+        /// For Deterministic encryption, a synthetic IV will be genenrated during encryption
+        /// For Randomized encryption, a random IV will be generated during encryption.
+        /// </param>
+        /// <param name="algorithmVersion">
+        /// Algorithm version
+        /// </param>
+        internal SqlAes256CbcAlgorithm(SqlAeadAes256CbcHmac256EncryptionKey encryptionKey, SqlClientEncryptionType encryptionType, byte algorithmVersion)
+            :base(encryptionKey, encryptionType, algorithmVersion)
+        { }
+
+        /// <summary>
+        /// Encryption Algorithm
+        /// Simply call the base class, indicating we don't need an authentication tag.
+        /// </summary>
+        /// <param name="plainText">Plaintext data to be encrypted</param>
+        /// <returns>Returns the ciphertext corresponding to the plaintext.</returns>
+        internal override byte[] EncryptData(byte[] plainText) {
+            return EncryptData(plainText, hasAuthenticationTag: false);
+        }
+
+        /// <summary>
+        /// Decryption Algorithm
+        /// Simply call the base class, indicating we don't have an authentication tag.
+        /// </summary>
+        /// <param name="cipherText"></param>
+        /// <returns></returns>
+        internal override byte[] DecryptData(byte[] cipherText) {
+            return base.DecryptData(cipherText, hasAuthenticationTag: false);
+        }
+    }
+}