Simple String Hashing in .NET

   1:  // MIT license   2:  // Copyright 2005-2008 Ken Egozi   3:  //    4:  // Permission is hereby granted, free of charge, to any person obtaining a copy   5:  // of this software and associated documentation files (the "Software"), to deal   6:  // in the Software without restriction, including without limitation the rights   7:  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell   8:  // copies of the Software, and to permit persons to whom the Software is   9:  // furnished to do so, subject to the following conditions:  10:  //   11:  // The above copyright notice and this permission notice shall be included in  12:  // all copies or substantial portions of the Software.  13:  //   14:  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR  15:  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,  16:  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE  17:  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER  18:  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,  19:  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN  20:  // THE SOFTWARE.  21:    22:  using System;  23:  using System.Collections.Generic;  24:  using System.Text;  25:  using System.Security.Cryptography;  26:  using System.Collections;  27:    28:  namespace KenEgozi.CryptographicServices  29:  {  30:  publicstaticclass Hashing  31:      {  32:  privatestatic Hashtable hashAlgorithms = Hashtable.Synchronized(new Hashtable());  33:    34:  /// <summary>  35:  /// Hashing a given string with SHA2.  36:  /// </summary>  37:  /// <param name="data">Data to hash</param>  38:  /// <returns>Hashed data</returns>  39:  publicstaticstring HashData(string data)  40:          {  41:  return HashData(data, HashType.SHA256);  42:          }  43:    44:  /// <summary>  45:  /// Hashing a given string with any of the supported hash algorithms.  46:  /// </summary>  47:  /// <param name="data">Data to hash</param>  48:  /// <param name="hashType">Hashing algorithm to use</param>  49:  /// <returns>Hashed data</returns>  50:  publicstaticstring HashData(string data, HashType hashType)  51:          {  52:              HashAlgorithm hash = GetHash(hashType);  53:  byte[] bytes = (new UnicodeEncoding()).GetBytes(data);  54:  byte[] hashed = hash.ComputeHash(bytes);  55:              StringBuilder sb = new StringBuilder(64);  56:  foreach (byte b in hashed)  57:                  sb.AppendFormat("{0:x2}", b);  58:  return sb.ToString();  59:          }  60:    61:  privatestatic HashAlgorithm GetHash(HashType hashType)  62:          {  63:  if (!hashAlgorithms.ContainsKey(hashType))  64:                  hashAlgorithms.Add(hashType, CreateaHashAlgorithm(hashType));  65:  return hashAlgorithms[hashType] as HashAlgorithm;  66:          }  67:    68:  privatestatic HashAlgorithm CreateaHashAlgorithm(HashType hashType)  69:          {  70:  switch (hashType)  71:              {  72:  case HashType.MD5:  73:  returnnew MD5CryptoServiceProvider();  74:  case HashType.SHA1:  75:  returnnew SHA1Managed();  76:  case HashType.SHA256:  77:  returnnew SHA256Managed();  78:  case HashType.SHA384:  79:  returnnew SHA384Managed();  80:  case HashType.SHA512:  81:  returnnew SHA512Managed();  82:  default:  83:  thrownew NotImplementedException();  84:              }  85:          }  86:      }  87:    88:  publicenum HashType  89:      {  90:          MD5,  91:          SHA1,  92:          SHA256,  93:          SHA384,  94:          SHA512  95:      }  96:  }