Initial Commit

iTechSharp/srcbc/crypto/paddings/ISO10126d2Padding.cs

@@ -0,0 +1,76 @@
+using System;
+using Org.BouncyCastle.Crypto;
+using Org.BouncyCastle.Security;
+
+
+namespace Org.BouncyCastle.Crypto.Paddings
+{
+
+    /**
+    * A padder that adds ISO10126-2 padding to a block.
+    */
+    public class ISO10126d2Padding: IBlockCipherPadding
+    {
+        private SecureRandom random;
+
+        /**
+        * Initialise the padder.
+        *
+        * @param random a SecureRandom if available.
+        */
+        public void Init(
+			SecureRandom random)
+            //throws ArgumentException
+        {
+			this.random = (random != null) ? random : new SecureRandom();
+        }
+
+		/**
+        * Return the name of the algorithm the cipher implements.
+        *
+        * @return the name of the algorithm the cipher implements.
+        */
+        public string PaddingName
+        {
+            get { return "ISO10126-2"; }
+        }
+
+		/**
+        * add the pad bytes to the passed in block, returning the
+        * number of bytes added.
+        */
+        public int AddPadding(
+            byte[]	input,
+            int		inOff)
+        {
+            byte code = (byte)(input.Length - inOff);
+
+            while (inOff < (input.Length - 1))
+            {
+                input[inOff] = (byte)random.NextInt();
+                inOff++;
+            }
+
+            input[inOff] = code;
+
+            return code;
+        }
+
+        /**
+        * return the number of pad bytes present in the block.
+        */
+        public int PadCount(byte[] input)
+            //throws InvalidCipherTextException
+        {
+            int count = input[input.Length - 1] & 0xff;
+
+            if (count > input.Length)
+            {
+                throw new InvalidCipherTextException("pad block corrupted");
+            }
+
+            return count;
+        }
+    }
+
+}