1 files changed, 89 insertions, 0 deletions

diff --git a/src/WixToolset.Core/Uuid.cs b/src/WixToolset.Core/Uuid.cs
new file mode 100644
index 00000000..2e599793
--- /dev/null
+++ b/src/WixToolset.Core/Uuid.cs
@@ -0,0 +1,89 @@
+// Copyright (c) .NET Foundation and contributors. All rights reserved. Licensed under the Microsoft Reciprocal License. See LICENSE.TXT file in the project root for full license information.
+
+namespace WixToolset
+{
+    using System;
+    using System.Net;
+    using System.Security.Cryptography;
+    using System.Text;
+
+    /// <summary>
+    /// Implementation of RFC 4122 - A Universally Unique Identifier (UUID) URN Namespace.
+    /// </summary>
+    internal sealed class Uuid
+    {
+        /// <summary>
+        /// Protect the constructor.
+        /// </summary>
+        private Uuid()
+        {
+        }
+
+        /// <summary>
+        /// Creates a version 3 name-based UUID.
+        /// </summary>
+        /// <param name="namespaceGuid">The namespace UUID.</param>
+        /// <param name="value">The value.</param>
+        /// <param name="backwardsCompatible">Flag to say to use MD5 instead of better SHA1.</param>
+        /// <returns>The UUID for the given namespace and value.</returns>
+        public static Guid NewUuid(Guid namespaceGuid, string value)
+        {
+            byte[] namespaceBytes = namespaceGuid.ToByteArray();
+            short uuidVersion = (short)0x5000;
+
+            // get the fields of the guid which are in host byte ordering
+            int timeLow = BitConverter.ToInt32(namespaceBytes, 0);
+            short timeMid = BitConverter.ToInt16(namespaceBytes, 4);
+            short timeHiAndVersion = BitConverter.ToInt16(namespaceBytes, 6);
+
+            // convert to network byte ordering
+            timeLow = IPAddress.HostToNetworkOrder(timeLow);
+            timeMid = IPAddress.HostToNetworkOrder(timeMid);
+            timeHiAndVersion = IPAddress.HostToNetworkOrder(timeHiAndVersion);
+
+            // get the bytes from the value
+            byte[] valueBytes = Encoding.Unicode.GetBytes(value);
+
+            // fill-in the hash input buffer
+            byte[] buffer = new byte[namespaceBytes.Length + valueBytes.Length];
+            Buffer.BlockCopy(BitConverter.GetBytes(timeLow), 0, buffer, 0, 4);
+            Buffer.BlockCopy(BitConverter.GetBytes(timeMid), 0, buffer, 4, 2);
+            Buffer.BlockCopy(BitConverter.GetBytes(timeHiAndVersion), 0, buffer, 6, 2);
+            Buffer.BlockCopy(namespaceBytes, 8, buffer, 8, 8);
+            Buffer.BlockCopy(valueBytes, 0, buffer, 16, valueBytes.Length);
+
+            // perform the appropriate hash of the namespace and value
+            byte[] hash;
+            using (SHA1 sha1 = SHA1.Create())
+            {
+                hash = sha1.ComputeHash(buffer);
+            }
+
+            // get the fields of the hash which are in network byte ordering
+            timeLow = BitConverter.ToInt32(hash, 0);
+            timeMid = BitConverter.ToInt16(hash, 4);
+            timeHiAndVersion = BitConverter.ToInt16(hash, 6);
+
+            // convert to network byte ordering
+            timeLow = IPAddress.NetworkToHostOrder(timeLow);
+            timeMid = IPAddress.NetworkToHostOrder(timeMid);
+            timeHiAndVersion = IPAddress.NetworkToHostOrder(timeHiAndVersion);
+
+            // set the version and variant bits
+            timeHiAndVersion &= 0x0FFF;
+            timeHiAndVersion += uuidVersion;
+            hash[8] &= 0x3F;
+            hash[8] |= 0x80;
+
+            // put back the converted values into a 128-bit value
+            byte[] guidBits = new byte[16];
+            Buffer.BlockCopy(hash, 0, guidBits, 0, 16);
+
+            Buffer.BlockCopy(BitConverter.GetBytes(timeLow), 0, guidBits, 0, 4);
+            Buffer.BlockCopy(BitConverter.GetBytes(timeMid), 0, guidBits, 4, 2);
+            Buffer.BlockCopy(BitConverter.GetBytes(timeHiAndVersion), 0, guidBits, 6, 2);
+
+            return new Guid(guidBits);
+        }
+    }
+}