1 files changed, 79 insertions, 0 deletions
diff --git a/crypto/src/asn1/x509/KeyUsage.cs b/crypto/src/asn1/x509/KeyUsage.cs
new file mode 100644
index 000000000..fef04e8b9
--- /dev/null
+++ b/crypto/src/asn1/x509/KeyUsage.cs
@@ -0,0 +1,79 @@
+namespace Org.BouncyCastle.Asn1.X509
+{
+    /**
+     * The KeyUsage object.
+     * <pre>
+     *    id-ce-keyUsage OBJECT IDENTIFIER ::=  { id-ce 15 }
+     *
+     *    KeyUsage ::= BIT STRING {
+     *         digitalSignature        (0),
+     *         nonRepudiation          (1),
+     *         keyEncipherment         (2),
+     *         dataEncipherment        (3),
+     *         keyAgreement            (4),
+     *         keyCertSign             (5),
+     *         cRLSign                 (6),
+     *         encipherOnly            (7),
+     *         decipherOnly            (8) }
+     * </pre>
+     */
+    public class KeyUsage
+        : DerBitString
+    {
+        public const int DigitalSignature = (1 << 7);
+        public const int NonRepudiation   = (1 << 6);
+        public const int KeyEncipherment  = (1 << 5);
+        public const int DataEncipherment = (1 << 4);
+        public const int KeyAgreement     = (1 << 3);
+        public const int KeyCertSign      = (1 << 2);
+        public const int CrlSign          = (1 << 1);
+        public const int EncipherOnly     = (1 << 0);
+        public const int DecipherOnly     = (1 << 15);
+
+		public static new KeyUsage GetInstance(
+			object obj)
+		{
+			if (obj is KeyUsage)
+			{
+				return (KeyUsage)obj;
+			}
+
+			if (obj is X509Extension)
+			{
+				return GetInstance(X509Extension.ConvertValueToObject((X509Extension) obj));
+			}
+
+			return new KeyUsage(DerBitString.GetInstance(obj));
+		}
+
+		/**
+         * Basic constructor.
+         *
+         * @param usage - the bitwise OR of the Key Usage flags giving the
+         * allowed uses for the key.
+         * e.g. (KeyUsage.keyEncipherment | KeyUsage.dataEncipherment)
+         */
+        public KeyUsage(
+			int usage)
+			: base(GetBytes(usage), GetPadBits(usage))
+        {
+        }
+
+		private KeyUsage(
+			DerBitString usage)
+			: base(usage.GetBytes(), usage.PadBits)
+        {
+        }
+
+		public override string ToString()
+        {
+			byte[] data = GetBytes();
+            if (data.Length == 1)
+            {
+				return "KeyUsage: 0x" + (data[0] & 0xff).ToString("X");
+            }
+
+			return "KeyUsage: 0x" + ((data[1] & 0xff) << 8 | (data[0] & 0xff)).ToString("X");
+        }
+    }
+}