Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/Security/CookieProtection.cs

@@ -0,0 +1,95 @@
+//------------------------------------------------------------------------------
+// <copyright file="CookieProtection.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+namespace System.Web.Security 
+{
+    using System;
+    using System.Web.Configuration;
+    using System.Web.Security.Cryptography;
+    
+
+    public enum CookieProtection
+    {
+
+        None, Validation, Encryption, All
+    }
+
+    internal class CookieProtectionHelper
+    {
+        internal static string Encode (CookieProtection cookieProtection, byte [] buf, Purpose purpose)
+        {
+            if (AspNetCryptoServiceProvider.Instance.IsDefaultProvider) {
+                // If we're configured to go through the new crypto routines, do so.
+                ICryptoService cryptoService = AspNetCryptoServiceProvider.Instance.GetCryptoService(purpose);
+                return HttpServerUtility.UrlTokenEncode(cryptoService.Protect(buf));
+            }
+
+#pragma warning disable 618 // calling obsolete methods
+            // Otherwise fall back to using MachineKeySection.
+            int count = buf.Length;
+            if (cookieProtection == CookieProtection.All || cookieProtection == CookieProtection.Validation)
+            {
+                byte[] bMac = MachineKeySection.HashData (buf, null, 0, count);
+
+                if (bMac == null)
+                    return null;
+                if (buf.Length >= count + bMac.Length)
+                {
+                    Buffer.BlockCopy (bMac, 0, buf, count, bMac.Length);
+                }
+                else
+                {
+                    byte[] bTemp = buf;
+                    buf = new byte[count + bMac.Length];
+                    Buffer.BlockCopy (bTemp, 0, buf, 0, count);
+                    Buffer.BlockCopy (bMac, 0, buf, count, bMac.Length);
+                }
+                count += bMac.Length;
+            }
+
+            if (cookieProtection == CookieProtection.All || cookieProtection == CookieProtection.Encryption)
+            {
+                buf = MachineKeySection.EncryptOrDecryptData (true, buf, null, 0, count);
+                count = buf.Length;
+            }
+            if (count < buf.Length)
+            {
+                byte[] bTemp = buf;
+                buf = new byte[count];
+                Buffer.BlockCopy (bTemp, 0, buf, 0, count);
+            }
+#pragma warning restore 618 // calling obsolete methods
+
+            return HttpServerUtility.UrlTokenEncode(buf);
+        }
+
+        internal static byte[] Decode (CookieProtection cookieProtection, string data, Purpose purpose)
+        {
+            byte[] buf = HttpServerUtility.UrlTokenDecode(data);
+            if (AspNetCryptoServiceProvider.Instance.IsDefaultProvider) {
+                // If we're configured to go through the new crypto routines, do so.
+                ICryptoService cryptoService = AspNetCryptoServiceProvider.Instance.GetCryptoService(purpose);
+                return cryptoService.Unprotect(buf);
+            }
+
+#pragma warning disable 618 // calling obsolete methods
+            // Otherwise fall back to using MachineKeySection.
+            if (buf == null || cookieProtection == CookieProtection.None)
+                return buf;
+            if (cookieProtection == CookieProtection.All || cookieProtection == CookieProtection.Encryption)
+            {
+                buf = MachineKeySection.EncryptOrDecryptData (false, buf, null, 0, buf.Length);
+                if (buf == null)
+                    return null;
+            }
+
+            if (cookieProtection == CookieProtection.All || cookieProtection == CookieProtection.Validation)
+                return MachineKeySection.GetUnHashedData(buf);
+            return buf;
+#pragma warning restore 618 // calling obsolete methods
+        }
+    }
+}