[corlib] Implements CryptoConfig::AddAlgorithm on all profiles

mcs/class/corlib/System.Security.Cryptography/CryptoConfig.Mobile.cs

@@ -38,17 +38,13 @@
 
 using System.Runtime.InteropServices;
 using System.Security.Permissions;
+using System.Collections.Generic;
 
 namespace System.Security.Cryptography {
 
 	[ComVisible (true)]
 	public partial class CryptoConfig {
 
-		public static void AddAlgorithm (Type algorithm, params string[] names)
-		{
-			throw new PlatformNotSupportedException ();
-		}
-
 		public static void AddOID (string oid, params string[] names)
 		{
 			throw new PlatformNotSupportedException ();
@@ -204,6 +200,16 @@ public static object CreateFromName (string name, params object[] args)
 				break;
 			}
 
+			lock (lockObject) {
+				Type algoClass = null;
+				if (algorithms?.TryGetValue (name, out algoClass) == true) {
+					try {
+						return Activator.CreateInstance (algoClass, args);
+					} catch {
+					}
+				}
+			}
+
 			try {
 				// last resort, the request type might be available (if care is taken for the type not to be linked 
 				// away) and that can allow some 3rd party code to work (e.g. extra algorithms) and make a few more
@@ -271,6 +277,11 @@ public static string MapNameToOID (string name)
 				return null;
 			}
 		}
+
+		static void Initialize ()
+		{
+			algorithms = new Dictionary<string, Type> (StringComparer.OrdinalIgnoreCase);
+		}
 	}
 }
 

mcs/class/corlib/System.Security.Cryptography/CryptoConfig.common.cs

@@ -29,9 +29,43 @@
 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 //
 
+using System.Collections.Generic;
+
 namespace System.Security.Cryptography {
 
-	public partial class CryptoConfig {
+	public partial class CryptoConfig
+	{
+		static readonly object lockObject = new object ();
+		static Dictionary<string,Type> algorithms;
+
+		public static void AddAlgorithm (Type algorithm, params string[] names)
+		{
+			if (algorithm == null)
+				throw new ArgumentNullException (nameof (algorithm));
+			if (!algorithm.IsVisible)
+				throw new ArgumentException ("Algorithms added to CryptoConfig must be accessable from outside their assembly.", nameof (algorithm));
+			if (names == null)
+				throw new ArgumentNullException (nameof (names));
+
+			var algorithmNames = new string [names.Length];
+			Array.Copy (names, algorithmNames, algorithmNames.Length);
+
+			foreach (string name in algorithmNames) {
+				if (string.IsNullOrEmpty (name)) {
+					throw new ArgumentException ("CryptoConfig cannot add a mapping for a null or empty name.");
+				}
+			}
+
+			lock (lockObject) {
+				if (algorithms == null) {
+					Initialize ();
+				}
+
+				foreach (string name in algorithmNames) {
+					algorithms [name] = algorithm;
+				}
+			}
+		}
 
 		public static byte[] EncodeOID (string str)
 		{

mcs/class/corlib/System.Security.Cryptography/CryptoConfig.cs

@@ -50,8 +50,6 @@ namespace System.Security.Cryptography {
 [ComVisible (true)]
 public partial class CryptoConfig {
 
-	static private object lockObject;
-	static private Dictionary<string,Type> algorithms;
 	static private Dictionary<string,string> unresolved_algorithms;
 	static private Dictionary<string,string> oids;
 
@@ -281,12 +279,6 @@ public partial class CryptoConfig {
 	// SHA512 provider
 	const string nameSHA512Provider = "System.Security.Cryptography.SHA512CryptoServiceProvider";
 	const string defaultSHA512Provider = "System.Security.Cryptography.SHA512CryptoServiceProvider" + system_core_assembly;
-	static CryptoConfig () 
-	{
-		// lock(this) is bad
-		// http://msdn.microsoft.com/library/en-us/dnaskdr/html/askgui06032003.asp?frame=true
-		lockObject = new object ();
-	}
 
 	private static void Initialize () 
 	{
@@ -562,20 +554,6 @@ public static string MapNameToOID (string name)
 		return result;
 	}
 
-	public static void AddAlgorithm (Type algorithm, params string[] names)
-	{
-		if (algorithm == null)
-				throw new ArgumentNullException ("algorithm");
-		if (names  == null)
-				throw new ArgumentNullException ("names");
-
-		foreach (string name in names) {
-				if (String.IsNullOrWhiteSpace (name))
-					throw new ArithmeticException ("names");
-				algorithms [name] = algorithm;
-		}
-	}
-
 	public static void AddOID (string oid, params string[] names)
 	{
 		if (oid == null)

mcs/class/corlib/Test/System.Security.Cryptography/CryptoConfigTest.cs

@@ -37,6 +37,10 @@ namespace MonoTests.System.Security.Cryptography {
 [TestFixture]
 public class CryptoConfigTest {
 
+	public class FakeAlgorithm
+	{
+	}
+
 	void CreateFromName (string name, string objectname)
 	{
 		object o = CryptoConfig.CreateFromName (name);
@@ -402,6 +406,14 @@ public void CCToString ()
 		CryptoConfig cc = new CryptoConfig ();
 		Assert.AreEqual ("System.Security.Cryptography.CryptoConfig", cc.ToString ());
 	}
+
+	[Test]
+	public void AddAlgorithm ()
+	{
+		CryptoConfig.AddAlgorithm (typeof (FakeAlgorithm), "test");
+		Assert.IsNotNull (CryptoConfig.CreateFromName ("test"));
+
+	}
 }
 
 }