(chocolatey#1144) Add HashConverter class

This class provides a method to convert base64 hashes into hex form,
returning the input if it is already in hex. It also returns the type
of the hash. Both are based on the length of the input hash. Sha1,
Sha256 and Sha512 are supported.

src/chocolatey/chocolatey.csproj

@@ -270,6 +270,7 @@
     <Compile Include="infrastructure.app\utility\ArgumentsUtility.cs" />
     <Compile Include="infrastructure.app\utility\PackageUtility.cs" />
     <Compile Include="infrastructure.app\validations\SystemStateValidation.cs" />
+    <Compile Include="infrastructure\cryptography\HashConverter.cs" />
     <Compile Include="infrastructure\filesystem\FileSystem.cs" />
     <Compile Include="FileSystemExtensions.cs" />
     <Compile Include="infrastructure\information\ExtensionInformation.cs" />

src/chocolatey/infrastructure/cryptography/HashConverter.cs

@@ -0,0 +1,65 @@
+// Copyright © 2017 - 2021 Chocolatey Software, Inc
+// Copyright © 2011 - 2017 RealDimensions Software, LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+//
+// You may obtain a copy of the License at
+//
+// 	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+using System;
+
+namespace chocolatey.infrastructure.cryptography
+{
+    public static class HashConverter
+    {
+        public static (string convertedHash, CryptoHashProviderType hashType) ConvertHashToHex(string hash)
+        {
+            // Sha 1 in base64
+            if (hash.Length.Equals(28))
+            {
+                return (BitConverter.ToString(Convert.FromBase64String(hash)).Replace("-", string.Empty), CryptoHashProviderType.Sha1);
+            }
+
+            // Sha 1 in hex
+            if (hash.Length.Equals(40))
+            {
+                return (hash, CryptoHashProviderType.Sha1);
+            }
+
+            // Sha 256 in base64
+            if (hash.Length.Equals(44))
+            {
+                return (BitConverter.ToString(Convert.FromBase64String(hash)).Replace("-", string.Empty), CryptoHashProviderType.Sha256);
+            }
+
+            // Sha 256 in hex
+            if (hash.Length.Equals(64))
+            {
+                return (hash, CryptoHashProviderType.Sha256);
+            }
+
+            // Sha 512 in base64
+            if (hash.Length.Equals(88))
+            {
+                return (BitConverter.ToString(Convert.FromBase64String(hash)).Replace("-", string.Empty), CryptoHashProviderType.Sha512);
+            }
+
+            // Sha 512 in hex
+            if (hash.Length.Equals(128))
+            {
+                return (hash, CryptoHashProviderType.Sha512);
+            }
+
+            "chocolatey".Log().Warn("Unknown Hash type, Length '{0}', Hash '{1}'".FormatWith(hash, hash.Length));
+            return (hash, CryptoHashProviderType.Unknown);
+        }
+    }
+}