init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/X509/Extension/X509ExtensionUtilities.cs

@@ -0,0 +1,77 @@
+using System;
+using System.Collections;
+using System.IO;
+using Org.BouncyCastle.Asn1;
+using Org.BouncyCastle.Asn1.X509;
+using Org.BouncyCastle.Security.Certificates;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.X509.Extension;
+
+public class X509ExtensionUtilities
+{
+	public static Asn1Object FromExtensionValue(Asn1OctetString extensionValue)
+	{
+		return Asn1Object.FromByteArray(extensionValue.GetOctets());
+	}
+
+	public static ICollection GetIssuerAlternativeNames(X509Certificate cert)
+	{
+		Asn1OctetString extensionValue = cert.GetExtensionValue(X509Extensions.IssuerAlternativeName);
+		return GetAlternativeName(extensionValue);
+	}
+
+	public static ICollection GetSubjectAlternativeNames(X509Certificate cert)
+	{
+		Asn1OctetString extensionValue = cert.GetExtensionValue(X509Extensions.SubjectAlternativeName);
+		return GetAlternativeName(extensionValue);
+	}
+
+	private static ICollection GetAlternativeName(Asn1OctetString extVal)
+	{
+		IList list = Platform.CreateArrayList();
+		if (extVal != null)
+		{
+			try
+			{
+				Asn1Sequence instance = Asn1Sequence.GetInstance(FromExtensionValue(extVal));
+				foreach (Asn1Encodable item in instance)
+				{
+					IList list2 = Platform.CreateArrayList();
+					GeneralName instance2 = GeneralName.GetInstance(item);
+					list2.Add(instance2.TagNo);
+					switch (instance2.TagNo)
+					{
+					case 0:
+					case 3:
+					case 5:
+						list2.Add(instance2.Name.ToAsn1Object());
+						break;
+					case 4:
+						list2.Add(X509Name.GetInstance(instance2.Name).ToString());
+						break;
+					case 1:
+					case 2:
+					case 6:
+						list2.Add(((IAsn1String)instance2.Name).GetString());
+						break;
+					case 8:
+						list2.Add(DerObjectIdentifier.GetInstance(instance2.Name).Id);
+						break;
+					case 7:
+						list2.Add(Asn1OctetString.GetInstance(instance2.Name).GetOctets());
+						break;
+					default:
+						throw new IOException("Bad tag number: " + instance2.TagNo);
+					}
+					list.Add(list2);
+				}
+			}
+			catch (Exception ex)
+			{
+				throw new CertificateParsingException(ex.Message);
+			}
+		}
+		return list;
+	}
+}