Get-AuthenticodeSignature: Add embedded cert opt

src/Microsoft.PowerShell.Security/security/SignatureCommands.cs

@@ -263,6 +263,14 @@ protected override void ProcessRecord()
     [OutputType(typeof(Signature))]
     public sealed class GetAuthenticodeSignatureCommand : SignatureCommandsBase
     {
+        /// <summary>
+        /// Property that sets the switch parameter that decides whether to retrieve embedded signatures only or
+        /// also signatures inside a catalogue file.
+        /// </summary>
+        [Parameter(ParameterSetName = "ByPath")]
+        [Parameter(ParameterSetName = "ByLiteralPath")]
+        public SwitchParameter EmbeddedSignature { get; set; }
+
         /// <summary>
         /// Initializes a new instance of the GetSignatureCommand class.
         /// </summary>
@@ -279,7 +287,7 @@ public sealed class GetAuthenticodeSignatureCommand : SignatureCommandsBase
         /// </returns>
         protected override Signature PerformAction(string filePath)
         {
-            return SignatureHelper.GetSignature(filePath, null);
+            return SignatureHelper.GetSignature(filePath, null, embeddedSignatureOnly: EmbeddedSignature);
         }
 
         /// <summary>

src/System.Management.Automation/security/Authenticode.cs

@@ -265,6 +265,9 @@ internal static class SignatureHelper
         /// </summary>
         /// <param name="fileName">Name of file to check.</param>
         /// <param name="fileContent">Content of file to check.</param>
+        /// <param name="embeddedSignatureOnly">
+        /// Get the embedded signature in the provided file rather than one inside a .cat file.
+        /// </param>
         /// <returns>Signature object.</returns>
         /// <exception cref="System.ArgumentException">
         /// Thrown if argument fileName is empty.
@@ -275,11 +278,14 @@ internal static class SignatureHelper
         /// <exception cref="System.IO.FileNotFoundException">
         /// Thrown if the file specified by argument fileName is not found.
         /// </exception>
-        internal static Signature GetSignature(string fileName, byte[] fileContent)
+        internal static Signature GetSignature(
+            string fileName,
+            byte[] fileContent,
+            bool embeddedSignatureOnly = false)
         {
             Signature signature = null;
 
-            if (fileContent == null)
+            if (!embeddedSignatureOnly && fileContent == null)
             {
                 // First, try to get the signature from the latest dotNet signing API.
                 signature = GetSignatureFromMSSecurityExtensions(fileName);