Add SharedFramework MSI Authoring

scripts/dotnet-cli-build/Utils/Utils.cs

@@ -1,6 +1,7 @@
 using System;
 using System.IO;
 using System.Runtime.InteropServices;
+using System.Security.Cryptography;
 
 namespace Microsoft.DotNet.Cli.Build
 {
@@ -34,5 +35,55 @@ namespace Microsoft.DotNet.Cli.Build
                 throw new PlatformNotSupportedException();
             }
         }
+
+        // Generate a Version 5 (SHA1 Name Based) Guid from a name.
+        public static Guid GenerateGuidFromName(string name)
+        {
+            // Any fixed GUID will do for a namespace.
+            Guid namespaceId = new Guid("28F1468D-672B-489A-8E0C-7C5B3030630C");
+
+            using (SHA1 hasher = SHA1.Create())
+            {
+                var nameBytes = System.Text.Encoding.UTF8.GetBytes(name ?? string.Empty);
+                var namespaceBytes = namespaceId.ToByteArray();
+
+                SwapGuidByteOrder(namespaceBytes);
+
+                var streamToHash = new byte[namespaceBytes.Length + nameBytes.Length];
+
+                Array.Copy(namespaceBytes, streamToHash, namespaceBytes.Length);
+                Array.Copy(nameBytes, 0, streamToHash, namespaceBytes.Length, nameBytes.Length);
+
+                var hashResult = hasher.ComputeHash(streamToHash);
+
+                var res = new byte[16];
+
+                Array.Copy(hashResult, res, res.Length);
+
+                unchecked { res[6] = (byte)(0x50 | (res[6] & 0x0F)); }
+                unchecked { res[8] = (byte)(0x40 | (res[8] & 0x3F)); }
+
+                SwapGuidByteOrder(res);
+
+                return new Guid(res);
+            }
+        }
+
+        // Do a byte order swap, .NET GUIDs store multi byte components in little
+        // endian.
+        private static void SwapGuidByteOrder(byte[] b)
+        {
+            Swap(b, 0, 3);
+            Swap(b, 1, 2);
+            Swap(b, 5, 6);
+            Swap(b, 7, 8);
+        }
+
+        private static void Swap(byte[] b, int x, int y)
+        {
+            byte t = b[x];
+            b[x] = b[y];
+            b[y] = t;
+        }
     }
 }