| /* |
| * |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| |
| using System; |
| using System.Security.Cryptography; |
| |
| namespace Apache.Qpid.Sasl |
| { |
| /// <summary> |
| /// Rough HMAC MD5 implementation as presented in |
| /// RFC 2104. Used because the HMACMD5 class in the |
| /// .NET framework is not available in v1.1. |
| /// </summary> |
| public sealed class MD5HMAC : IDisposable |
| { |
| private const int BLOCK_LEN = 64; |
| private MD5 _hash; |
| private byte[] _key; |
| private byte[] _ipad; |
| private byte[] _opad; |
| |
| public MD5HMAC(byte[] key) |
| { |
| if ( key == null || key.Length == 0 ) |
| throw new ArgumentNullException("key"); |
| |
| _hash = new MD5CryptoServiceProvider(); |
| |
| byte[] theKey = key; |
| if ( theKey.Length > BLOCK_LEN ) |
| { |
| theKey = _hash.ComputeHash(theKey); |
| } |
| // pad key with 0's up to BLOCK_LEN |
| _key = new byte[BLOCK_LEN]; |
| Array.Copy(theKey, _key, theKey.Length); |
| |
| CreatePads(); |
| } |
| |
| public byte[] ComputeHash(byte[] input) |
| { |
| // H(K XOR opad, H(K XOR ipad, text)) |
| return H(_opad, H(_ipad, input)); |
| } |
| |
| public void Dispose() |
| { |
| if ( _hash != null ) |
| { |
| ((IDisposable)_hash).Dispose(); |
| _hash = null; |
| } |
| } |
| |
| #region Private Methods |
| // |
| // Private Methods |
| // |
| |
| private void CreatePads() |
| { |
| _ipad = new byte[BLOCK_LEN]; |
| _opad = new byte[BLOCK_LEN]; |
| for ( int i = 0; i < BLOCK_LEN; i++ ) |
| { |
| _ipad[i] = 0x36; |
| _opad[i] = 0x5c; |
| } |
| |
| XOR(_ipad, _key); |
| XOR(_opad, _key); |
| } |
| |
| private static void XOR(byte[] dest, byte[] other) |
| { |
| // assume both are same size |
| for ( int i = 0; i < dest.Length; i++ ) |
| { |
| dest[i] ^= other[i]; |
| } |
| } |
| |
| private byte[] H(byte[] v1, byte[] v2) |
| { |
| byte[] total = new byte[v1.Length + v2.Length]; |
| Array.Copy(v1, total, v1.Length); |
| Array.Copy(v2, 0, total, v1.Length, v2.Length); |
| |
| return _hash.ComputeHash(total); |
| } |
| |
| #endregion // Private Methods |
| |
| } // class MD5HMAC |
| |
| } // namespace Apache.Qpid.Sasl |