/*
THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
PARTICULAR PURPOSE.
This is sample code and is freely distributable.
*/
using System;
using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Web;
namespace Wmb.Web {
/// <summary>
/// The StringUtility class holds the extensions and/or helpermethods for the String class.
/// </summary>
public static class EcryptionUtility {
/// <summary>
/// Encrypts the value by password and salt.
/// </summary>
/// <param name="value">The value.</param>
/// <param name="password">The password.</param>
/// <param name="salt">The salt.</param>
/// <returns>The encrypted bytes</returns>
public static byte[] PasswordEncrypt(this byte[] value, string password, string salt) {
if (value == null) {
throw new ArgumentNullException("value");
}
if (string.IsNullOrEmpty(password)) {
throw new ArgumentNullException("password");
}
if (string.IsNullOrEmpty(salt)) {
throw new ArgumentNullException("salt");
}
byte[] retVal = null;
Rijndael rijndaelAlg = CreateRijndael(password, salt);
using (MemoryStream memoryStream = new MemoryStream())
using (CryptoStream cryptoStream = new CryptoStream(memoryStream,
rijndaelAlg.CreateEncryptor(),
CryptoStreamMode.Write)) {
cryptoStream.Write(value, 0, value.Length);
cryptoStream.Close();
retVal = memoryStream.ToArray();
}
return retVal;
}
/// <summary>
/// Decrypts the value by password and salt.
/// </summary>
/// <param name="value">The value.</param>
/// <param name="password">The password.</param>
/// <param name="salt">The salt.</param>
/// <returns>The decrypted bytes</returns>
public static byte[] PasswordDecrypt(this byte[] value, string password, string salt) {
if (value == null) {
throw new ArgumentNullException("value");
}
if (string.IsNullOrEmpty(password)) {
throw new ArgumentNullException("password");
}
if (string.IsNullOrEmpty(salt)) {
throw new ArgumentNullException("salt");
}
byte[] retVal = null;
Rijndael rijndaelAlg = CreateRijndael(password, salt);
using (MemoryStream memoryStream = new MemoryStream())
using (CryptoStream cryptoStream = new CryptoStream(memoryStream,
rijndaelAlg.CreateDecryptor(),
CryptoStreamMode.Write)) {
cryptoStream.Write(value, 0, value.Length);
cryptoStream.Close();
retVal = memoryStream.ToArray();
}
return retVal;
}
/// <summary>
/// Ecrypts the value to a url encoded string.
/// </summary>
/// <param name="value">The value.</param>
/// <param name="password">The password.</param>
/// <param name="salt">The salt.</param>
/// <returns>The encrypted and url encoded string</returns>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1055:UriReturnValuesShouldNotBeStrings", Justification="This method does not return a Uri.")]
public static string UrlEncodedPasswordEncrypt(this string value, string password, string salt) {
if (value == null) {
throw new ArgumentNullException("value");
}
if (string.IsNullOrEmpty(password)) {
throw new ArgumentNullException("password");
}
if (string.IsNullOrEmpty(salt)) {
throw new ArgumentNullException("salt");
}
string retVal = null;
byte[] bytesToEncrypt = Encoding.Unicode.GetBytes(value);
byte[] encryptedValue = bytesToEncrypt.PasswordEncrypt(password, salt);
retVal = HttpServerUtility.UrlTokenEncode(encryptedValue);
return retVal;
}
/// <summary>
/// Decrypts the url encoded value.
/// </summary>
/// <param name="value">The value.</param>
/// <param name="password">The password.</param>
/// <param name="salt">The salt.</param>
/// <returns>The decrypted and url decoded string</returns>
[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1055:UriReturnValuesShouldNotBeStrings", Justification="This method does not return a Uri.")]
public static string UrlEncodedPasswordDecrypt(this string value, string password, string salt) {
if (value == null) {
throw new ArgumentNullException("value");
}
if (string.IsNullOrEmpty(password)) {
throw new ArgumentNullException("password");
}
if (string.IsNullOrEmpty(salt)) {
throw new ArgumentNullException("salt");
}
string retVal = null;
byte[] bytesToDecrypt = HttpServerUtility.UrlTokenDecode(value);
byte[] decryptedValue = bytesToDecrypt.PasswordDecrypt(password, salt);
retVal = Encoding.Unicode.GetString(decryptedValue);
return retVal;
}
private static Rijndael CreateRijndael(string password, string salt) {
byte[] saltBytes = Encoding.Unicode.GetBytes(salt);
PasswordDeriveBytes passwordDeriveBytes = new PasswordDeriveBytes(password,
saltBytes);
Rijndael rijndael = Rijndael.Create();
rijndael.Key = passwordDeriveBytes.GetBytes(32);
rijndael.IV = passwordDeriveBytes.GetBytes(16);
return rijndael;
}
}
}
Security
Provides the Unix crypt() encryption algorithm.
// <copyright file="UnixCrypt.cs" company="Cédric Belin">
// This sourcecode is a port from Java to C#.
// The original (Java) version was made by John Dumas and can be found at: http://www.dynamic.net.au/christos/crypt/UnixCrypt.txt
// </copyright>
// <summary>
// Implémentation de la classe <c>DigiWar.Security.Cryptography.UnixCrypt</c>.
// </summary>
// <author>$Author: cedx $</author>
// <date>$Date: 2009-09-10 19:44:34 +0200 (jeu. 10 sept. 2009) $</date>
// <version>$Revision: 1827 $</version>
using System;
using System.Linq;
using System.Text;
////
/// <summary>
/// Provides the Unix crypt() encryption algorithm.
/// </summary>
/// <remarks>
/// This class is a port from Java source. I do not understand the underlying algorithms, I just converted it to C# and it works.
/// Because I do not understand the underlying algorithms I cannot give most of the variables useful names. I have no clue what their
/// significance is. I tried to give the variable names as much meaning as possible, but the original source just called them a, b, c , etc...
///
/// A very important thing to note is that all ints in this code are UNSIGNED ints! Do not change this, ever!!! It will seriously fuckup the working
/// of this class. It uses major bitshifting and while Java gives you the >>> operator to signify a right bitshift WITHOUT setting the MSB for
/// a signed int, C# does not have this operator and will just set the new MSB for you if it happened to be set the moment you bitshifted it.
/// This is undesirable for most bitshifts and in the cases it did matter, I casted the variable back to an int. This was only required where
/// a variable was on the right-side of a bitshift operator.
/// </remarks>
internal static class UnixCrypt
{
/// <value>
/// The list with characters allowed in a Unix encrypted password.
/// It is used to randomly chose two characters for use in the encryption.
/// </value>
private const string m_encryptionSaltCharacters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789./";
/// <value>
/// A lookup-table, presumably filled with some sort of encryption key.
/// It is used to calculate the index to the m_SPTranslationTable lookup-table.
/// </value>
private static readonly uint[] m_saltTranslation =
{
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
0x0A, 0x0B, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A,
0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10, 0x11, 0x12,
0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1A,
0x1B, 0x1C, 0x1D, 0x1E, 0x1F, 0x20, 0x21, 0x22,
0x23, 0x24, 0x25, 0x20, 0x21, 0x22, 0x23, 0x24,
0x25, 0x26, 0x27, 0x28, 0x29, 0x2A, 0x2B, 0x2C,
0x2D, 0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34,
0x35, 0x36, 0x37, 0x38, 0x39, 0x3A, 0x3B, 0x3C,
0x3D, 0x3E, 0x3F, 0x00, 0x00, 0x00, 0x00, 0x00,
};
/// <value>
/// A lookup-table.
/// It is used to calculate the index to the m_skb lookup-table.
/// </value>
private static readonly bool[] m_shifts =
{
false, false, true, true, true, true, true, true,
false, true, true, true, true, true, true, false
};
/// <value>
/// A lookup-table.
/// It is used the dynamically create the schedule lookup-table.
/// </value>
private static readonly uint[,] m_skb =
{
{
/* for C bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
0x00000000, 0x00000010, 0x20000000, 0x20000010,
0x00010000, 0x00010010, 0x20010000, 0x20010010,
0x00000800, 0x00000810, 0x20000800, 0x20000810,
0x00010800, 0x00010810, 0x20010800, 0x20010810,
0x00000020, 0x00000030, 0x20000020, 0x20000030,
0x00010020, 0x00010030, 0x20010020, 0x20010030,
0x00000820, 0x00000830, 0x20000820, 0x20000830,
0x00010820, 0x00010830, 0x20010820, 0x20010830,
0x00080000, 0x00080010, 0x20080000, 0x20080010,
0x00090000, 0x00090010, 0x20090000, 0x20090010,
0x00080800, 0x00080810, 0x20080800, 0x20080810,
0x00090800, 0x00090810, 0x20090800, 0x20090810,
0x00080020, 0x00080030, 0x20080020, 0x20080030,
0x00090020, 0x00090030, 0x20090020, 0x20090030,
0x00080820, 0x00080830, 0x20080820, 0x20080830,
0x00090820, 0x00090830, 0x20090820, 0x20090830,
},
{
/* for C bits (numbered as per FIPS 46) 7 8 10 11 12 13 */
0x00000000, 0x02000000, 0x00002000, 0x02002000,
0x00200000, 0x02200000, 0x00202000, 0x02202000,
0x00000004, 0x02000004, 0x00002004, 0x02002004,
0x00200004, 0x02200004, 0x00202004, 0x02202004,
0x00000400, 0x02000400, 0x00002400, 0x02002400,
0x00200400, 0x02200400, 0x00202400, 0x02202400,
0x00000404, 0x02000404, 0x00002404, 0x02002404,
0x00200404, 0x02200404, 0x00202404, 0x02202404,
0x10000000, 0x12000000, 0x10002000, 0x12002000,
0x10200000, 0x12200000, 0x10202000, 0x12202000,
0x10000004, 0x12000004, 0x10002004, 0x12002004,
0x10200004, 0x12200004, 0x10202004, 0x12202004,
0x10000400, 0x12000400, 0x10002400, 0x12002400,
0x10200400, 0x12200400, 0x10202400, 0x12202400,
0x10000404, 0x12000404, 0x10002404, 0x12002404,
0x10200404, 0x12200404, 0x10202404, 0x12202404,
},
{
/* for C bits (numbered as per FIPS 46) 14 15 16 17 19 20 */
0x00000000, 0x00000001, 0x00040000, 0x00040001,
0x01000000, 0x01000001, 0x01040000, 0x01040001,
0x00000002, 0x00000003, 0x00040002, 0x00040003,
0x01000002, 0x01000003, 0x01040002, 0x01040003,
0x00000200, 0x00000201, 0x00040200, 0x00040201,
0x01000200, 0x01000201, 0x01040200, 0x01040201,
0x00000202, 0x00000203, 0x00040202, 0x00040203,
0x01000202, 0x01000203, 0x01040202, 0x01040203,
0x08000000, 0x08000001, 0x08040000, 0x08040001,
0x09000000, 0x09000001, 0x09040000, 0x09040001,
0x08000002, 0x08000003, 0x08040002, 0x08040003,
0x09000002, 0x09000003, 0x09040002, 0x09040003,
0x08000200, 0x08000201, 0x08040200, 0x08040201,
0x09000200, 0x09000201, 0x09040200, 0x09040201,
0x08000202, 0x08000203, 0x08040202, 0x08040203,
0x09000202, 0x09000203, 0x09040202, 0x09040203,
},
{
/* for C bits (numbered as per FIPS 46) 21 23 24 26 27 28 */
0x00000000, 0x00100000, 0x00000100, 0x00100100,
0x00000008, 0x00100008, 0x00000108, 0x00100108,
0x00001000, 0x00101000, 0x00001100, 0x00101100,
0x00001008, 0x00101008, 0x00001108, 0x00101108,
0x04000000, 0x04100000, 0x04000100, 0x04100100,
0x04000008, 0x04100008, 0x04000108, 0x04100108,
0x04001000, 0x04101000, 0x04001100, 0x04101100,
0x04001008, 0x04101008, 0x04001108, 0x04101108,
0x00020000, 0x00120000, 0x00020100, 0x00120100,
0x00020008, 0x00120008, 0x00020108, 0x00120108,
0x00021000, 0x00121000, 0x00021100, 0x00121100,
0x00021008, 0x00121008, 0x00021108, 0x00121108,
0x04020000, 0x04120000, 0x04020100, 0x04120100,
0x04020008, 0x04120008, 0x04020108, 0x04120108,
0x04021000, 0x04121000, 0x04021100, 0x04121100,
0x04021008, 0x04121008, 0x04021108, 0x04121108,
},
{
/* for D bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
0x00000000, 0x10000000, 0x00010000, 0x10010000,
0x00000004, 0x10000004, 0x00010004, 0x10010004,
0x20000000, 0x30000000, 0x20010000, 0x30010000,
0x20000004, 0x30000004, 0x20010004, 0x30010004,
0x00100000, 0x10100000, 0x00110000, 0x10110000,
0x00100004, 0x10100004, 0x00110004, 0x10110004,
0x20100000, 0x30100000, 0x20110000, 0x30110000,
0x20100004, 0x30100004, 0x20110004, 0x30110004,
0x00001000, 0x10001000, 0x00011000, 0x10011000,
0x00001004, 0x10001004, 0x00011004, 0x10011004,
0x20001000, 0x30001000, 0x20011000, 0x30011000,
0x20001004, 0x30001004, 0x20011004, 0x30011004,
0x00101000, 0x10101000, 0x00111000, 0x10111000,
0x00101004, 0x10101004, 0x00111004, 0x10111004,
0x20101000, 0x30101000, 0x20111000, 0x30111000,
0x20101004, 0x30101004, 0x20111004, 0x30111004,
},
{
/* for D bits (numbered as per FIPS 46) 8 9 11 12 13 14 */
0x00000000, 0x08000000, 0x00000008, 0x08000008,
0x00000400, 0x08000400, 0x00000408, 0x08000408,
0x00020000, 0x08020000, 0x00020008, 0x08020008,
0x00020400, 0x08020400, 0x00020408, 0x08020408,
0x00000001, 0x08000001, 0x00000009, 0x08000009,
0x00000401, 0x08000401, 0x00000409, 0x08000409,
0x00020001, 0x08020001, 0x00020009, 0x08020009,
0x00020401, 0x08020401, 0x00020409, 0x08020409,
0x02000000, 0x0A000000, 0x02000008, 0x0A000008,
0x02000400, 0x0A000400, 0x02000408, 0x0A000408,
0x02020000, 0x0A020000, 0x02020008, 0x0A020008,
0x02020400, 0x0A020400, 0x02020408, 0x0A020408,
0x02000001, 0x0A000001, 0x02000009, 0x0A000009,
0x02000401, 0x0A000401, 0x02000409, 0x0A000409,
0x02020001, 0x0A020001, 0x02020009, 0x0A020009,
0x02020401, 0x0A020401, 0x02020409, 0x0A020409,
},
{
/* for D bits (numbered as per FIPS 46) 16 17 18 19 20 21 */
0x00000000, 0x00000100, 0x00080000, 0x00080100,
0x01000000, 0x01000100, 0x01080000, 0x01080100,
0x00000010, 0x00000110, 0x00080010, 0x00080110,
0x01000010, 0x01000110, 0x01080010, 0x01080110,
0x00200000, 0x00200100, 0x00280000, 0x00280100,
0x01200000, 0x01200100, 0x01280000, 0x01280100,
0x00200010, 0x00200110, 0x00280010, 0x00280110,
0x01200010, 0x01200110, 0x01280010, 0x01280110,
0x00000200, 0x00000300, 0x00080200, 0x00080300,
0x01000200, 0x01000300, 0x01080200, 0x01080300,
0x00000210, 0x00000310, 0x00080210, 0x00080310,
0x01000210, 0x01000310, 0x01080210, 0x01080310,
0x00200200, 0x00200300, 0x00280200, 0x00280300,
0x01200200, 0x01200300, 0x01280200, 0x01280300,
0x00200210, 0x00200310, 0x00280210, 0x00280310,
0x01200210, 0x01200310, 0x01280210, 0x01280310,
},
{
/* for D bits (numbered as per FIPS 46) 22 23 24 25 27 28 */
0x00000000, 0x04000000, 0x00040000, 0x04040000,
0x00000002, 0x04000002, 0x00040002, 0x04040002,
0x00002000, 0x04002000, 0x00042000, 0x04042000,
0x00002002, 0x04002002, 0x00042002, 0x04042002,
0x00000020, 0x04000020, 0x00040020, 0x04040020,
0x00000022, 0x04000022, 0x00040022, 0x04040022,
0x00002020, 0x04002020, 0x00042020, 0x04042020,
0x00002022, 0x04002022, 0x00042022, 0x04042022,
0x00000800, 0x04000800, 0x00040800, 0x04040800,
0x00000802, 0x04000802, 0x00040802, 0x04040802,
0x00002800, 0x04002800, 0x00042800, 0x04042800,
0x00002802, 0x04002802, 0x00042802, 0x04042802,
0x00000820, 0x04000820, 0x00040820, 0x04040820,
0x00000822, 0x04000822, 0x00040822, 0x04040822,
0x00002820, 0x04002820, 0x00042820, 0x04042820,
0x00002822, 0x04002822, 0x00042822, 0x04042822,
}
};
/// <value>
/// A lookup-table.
/// It is used to calculate two ints that are used to encrypt the password.
/// </value>
private static readonly uint[,] m_SPTranslationTable =
{
{
/* nibble 0 */
0x00820200, 0x00020000, 0x80800000, 0x80820200,
0x00800000, 0x80020200, 0x80020000, 0x80800000,
0x80020200, 0x00820200, 0x00820000, 0x80000200,
0x80800200, 0x00800000, 0x00000000, 0x80020000,
0x00020000, 0x80000000, 0x00800200, 0x00020200,
0x80820200, 0x00820000, 0x80000200, 0x00800200,
0x80000000, 0x00000200, 0x00020200, 0x80820000,
0x00000200, 0x80800200, 0x80820000, 0x00000000,
0x00000000, 0x80820200, 0x00800200, 0x80020000,
0x00820200, 0x00020000, 0x80000200, 0x00800200,
0x80820000, 0x00000200, 0x00020200, 0x80800000,
0x80020200, 0x80000000, 0x80800000, 0x00820000,
0x80820200, 0x00020200, 0x00820000, 0x80800200,
0x00800000, 0x80000200, 0x80020000, 0x00000000,
0x00020000, 0x00800000, 0x80800200, 0x00820200,
0x80000000, 0x80820000, 0x00000200, 0x80020200,
},
{
/* nibble 1 */
0x10042004, 0x00000000, 0x00042000, 0x10040000,
0x10000004, 0x00002004, 0x10002000, 0x00042000,
0x00002000, 0x10040004, 0x00000004, 0x10002000,
0x00040004, 0x10042000, 0x10040000, 0x00000004,
0x00040000, 0x10002004, 0x10040004, 0x00002000,
0x00042004, 0x10000000, 0x00000000, 0x00040004,
0x10002004, 0x00042004, 0x10042000, 0x10000004,
0x10000000, 0x00040000, 0x00002004, 0x10042004,
0x00040004, 0x10042000, 0x10002000, 0x00042004,
0x10042004, 0x00040004, 0x10000004, 0x00000000,
0x10000000, 0x00002004, 0x00040000, 0x10040004,
0x00002000, 0x10000000, 0x00042004, 0x10002004,
0x10042000, 0x00002000, 0x00000000, 0x10000004,
0x00000004, 0x10042004, 0x00042000, 0x10040000,
0x10040004, 0x00040000, 0x00002004, 0x10002000,
0x10002004, 0x00000004, 0x10040000, 0x00042000,
},
{
/* nibble 2 */
0x41000000, 0x01010040, 0x00000040, 0x41000040,
0x40010000, 0x01000000, 0x41000040, 0x00010040,
0x01000040, 0x00010000, 0x01010000, 0x40000000,
0x41010040, 0x40000040, 0x40000000, 0x41010000,
0x00000000, 0x40010000, 0x01010040, 0x00000040,
0x40000040, 0x41010040, 0x00010000, 0x41000000,
0x41010000, 0x01000040, 0x40010040, 0x01010000,
0x00010040, 0x00000000, 0x01000000, 0x40010040,
0x01010040, 0x00000040, 0x40000000, 0x00010000,
0x40000040, 0x40010000, 0x01010000, 0x41000040,
0x00000000, 0x01010040, 0x00010040, 0x41010000,
0x40010000, 0x01000000, 0x41010040, 0x40000000,
0x40010040, 0x41000000, 0x01000000, 0x41010040,
0x00010000, 0x01000040, 0x41000040, 0x00010040,
0x01000040, 0x00000000, 0x41010000, 0x40000040,
0x41000000, 0x40010040, 0x00000040, 0x01010000,
},
{
/* nibble 3 */
0x00100402, 0x04000400, 0x00000002, 0x04100402,
0x00000000, 0x04100000, 0x04000402, 0x00100002,
0x04100400, 0x04000002, 0x04000000, 0x00000402,
0x04000002, 0x00100402, 0x00100000, 0x04000000,
0x04100002, 0x00100400, 0x00000400, 0x00000002,
0x00100400, 0x04000402, 0x04100000, 0x00000400,
0x00000402, 0x00000000, 0x00100002, 0x04100400,
0x04000400, 0x04100002, 0x04100402, 0x00100000,
0x04100002, 0x00000402, 0x00100000, 0x04000002,
0x00100400, 0x04000400, 0x00000002, 0x04100000,
0x04000402, 0x00000000, 0x00000400, 0x00100002,
0x00000000, 0x04100002, 0x04100400, 0x00000400,
0x04000000, 0x04100402, 0x00100402, 0x00100000,
0x04100402, 0x00000002, 0x04000400, 0x00100402,
0x00100002, 0x00100400, 0x04100000, 0x04000402,
0x00000402, 0x04000000, 0x04000002, 0x04100400,
},
{
/* nibble 4 */
0x02000000, 0x00004000, 0x00000100, 0x02004108,
0x02004008, 0x02000100, 0x00004108, 0x02004000,
0x00004000, 0x00000008, 0x02000008, 0x00004100,
0x02000108, 0x02004008, 0x02004100, 0x00000000,
0x00004100, 0x02000000, 0x00004008, 0x00000108,
0x02000100, 0x00004108, 0x00000000, 0x02000008,
0x00000008, 0x02000108, 0x02004108, 0x00004008,
0x02004000, 0x00000100, 0x00000108, 0x02004100,
0x02004100, 0x02000108, 0x00004008, 0x02004000,
0x00004000, 0x00000008, 0x02000008, 0x02000100,
0x02000000, 0x00004100, 0x02004108, 0x00000000,
0x00004108, 0x02000000, 0x00000100, 0x00004008,
0x02000108, 0x00000100, 0x00000000, 0x02004108,
0x02004008, 0x02004100, 0x00000108, 0x00004000,
0x00004100, 0x02004008, 0x02000100, 0x00000108,
0x00000008, 0x00004108, 0x02004000, 0x02000008,
},
{
/* nibble 5 */
0x20000010, 0x00080010, 0x00000000, 0x20080800,
0x00080010, 0x00000800, 0x20000810, 0x00080000,
0x00000810, 0x20080810, 0x00080800, 0x20000000,
0x20000800, 0x20000010, 0x20080000, 0x00080810,
0x00080000, 0x20000810, 0x20080010, 0x00000000,
0x00000800, 0x00000010, 0x20080800, 0x20080010,
0x20080810, 0x20080000, 0x20000000, 0x00000810,
0x00000010, 0x00080800, 0x00080810, 0x20000800,
0x00000810, 0x20000000, 0x20000800, 0x00080810,
0x20080800, 0x00080010, 0x00000000, 0x20000800,
0x20000000, 0x00000800, 0x20080010, 0x00080000,
0x00080010, 0x20080810, 0x00080800, 0x00000010,
0x20080810, 0x00080800, 0x00080000, 0x20000810,
0x20000010, 0x20080000, 0x00080810, 0x00000000,
0x00000800, 0x20000010, 0x20000810, 0x20080800,
0x20080000, 0x00000810, 0x00000010, 0x20080010,
},
{
/* nibble 6 */
0x00001000, 0x00000080, 0x00400080, 0x00400001,
0x00401081, 0x00001001, 0x00001080, 0x00000000,
0x00400000, 0x00400081, 0x00000081, 0x00401000,
0x00000001, 0x00401080, 0x00401000, 0x00000081,
0x00400081, 0x00001000, 0x00001001, 0x00401081,
0x00000000, 0x00400080, 0x00400001, 0x00001080,
0x00401001, 0x00001081, 0x00401080, 0x00000001,
0x00001081, 0x00401001, 0x00000080, 0x00400000,
0x00001081, 0x00401000, 0x00401001, 0x00000081,
0x00001000, 0x00000080, 0x00400000, 0x00401001,
0x00400081, 0x00001081, 0x00001080, 0x00000000,
0x00000080, 0x00400001, 0x00000001, 0x00400080,
0x00000000, 0x00400081, 0x00400080, 0x00001080,
0x00000081, 0x00001000, 0x00401081, 0x00400000,
0x00401080, 0x00000001, 0x00001001, 0x00401081,
0x00400001, 0x00401080, 0x00401000, 0x00001001,
},
{
/* nibble 7 */
0x08200020, 0x08208000, 0x00008020, 0x00000000,
0x08008000, 0x00200020, 0x08200000, 0x08208020,
0x00000020, 0x08000000, 0x00208000, 0x00008020,
0x00208020, 0x08008020, 0x08000020, 0x08200000,
0x00008000, 0x00208020, 0x00200020, 0x08008000,
0x08208020, 0x08000020, 0x00000000, 0x00208000,
0x08000000, 0x00200000, 0x08008020, 0x08200020,
0x00200000, 0x00008000, 0x08208000, 0x00000020,
0x00200000, 0x00008000, 0x08000020, 0x08208020,
0x00008020, 0x08000000, 0x00000000, 0x00208000,
0x08200020, 0x08008020, 0x08008000, 0x00200020,
0x08208000, 0x00000020, 0x00200020, 0x08008000,
0x08208020, 0x00200000, 0x08200000, 0x08000020,
0x00208000, 0x00008020, 0x08008020, 0x08200000,
0x00000020, 0x08208000, 0x00208020, 0x00000000,
0x08000000, 0x08200020, 0x00008000, 0x00208020
}
};
/// <value>
/// A lookup-table filled with printable characters.
/// It is used to make sure the encrypted password contains only printable characters. It is filled with
/// ASCII characters 46 - 122 (from the dot (.) untill (including) the lowercase 'z').
/// </value>
private static readonly uint[] m_characterConversionTable =
{
0x2E, 0x2F, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35,
0x36, 0x37, 0x38, 0x39, 0x41, 0x42, 0x43, 0x44,
0x45, 0x46, 0x47, 0x48, 0x49, 0x4A, 0x4B, 0x4C,
0x4D, 0x4E, 0x4F, 0x50, 0x51, 0x52, 0x53, 0x54,
0x55, 0x56, 0x57, 0x58, 0x59, 0x5A, 0x61, 0x62,
0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6A,
0x6B, 0x6C, 0x6D, 0x6E, 0x6F, 0x70, 0x71, 0x72,
0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7A
};
/// <value>
/// Marks the size of the dynamically created schedule lookup-table.
/// </value>
private const int m_desIterations = 16;
/// <summary>
/// Converts four seperate bytes into one uint.
/// </summary>
/// <param name="inputBytes">The bytes to use for the conversion.</param>
/// <param name="offset">The offset at which to start in the inputBytes buffer.</param>
/// <returns></returns>
private static uint FourBytesToInt(byte[] inputBytes, uint offset)
{
// I used an int here because the compiler would complain the stuff below would require a cast from int to uint.
// To keep the code cleaner I opted to use an int and cast it when I returned it.
int resultValue = 0;
resultValue = (inputBytes[offset++] & 0xFF);
resultValue |= (inputBytes[offset++] & 0xFF) << 8;
resultValue |= (inputBytes[offset++] & 0xFF) << 16;
resultValue |= (inputBytes[offset++]& 0xFF) << 24;
return (uint)resultValue;
}
/// <summary>
/// Converts an uint into 4 seperate bytes.
/// </summary>
/// <param name="inputInt">The uint to convert.</param>
/// <param name="outputBytes">The byte buffer into which to store the result.</param>
/// <param name="offset">The offset to start storing at in the outputBytes buffer.</param>
private static void IntToFourBytes(uint inputInt, byte[] outputBytes, uint offset)
{
outputBytes[offset++] = (byte)(inputInt & 0xFF);
outputBytes[offset++] = (byte)((inputInt >> 8) & 0xFF);
outputBytes[offset++] = (byte)((inputInt >> 16) & 0xFF);
outputBytes[offset++] = (byte)((inputInt >> 24) & 0xFF);
}
/// <summary>
/// Performs some operation on 4 uints. It's labeled PERM_OP in the original source.
/// </summary>
/// <param name="firstInt">The first uint to use.</param>
/// <param name="secondInt">The second uint to use.</param>
/// <param name="thirdInt">The third uint to use.</param>
/// <param name="fourthInt">The fourth uint to use.</param>
/// <param name="operationResults">An array of 2 uints that are the result of this operation.</param>
private static void PermOperation(uint firstInt, uint secondInt, uint thirdInt, uint fourthInt, uint[] operationResults)
{
// Because here an uint variable is at the right side of a bitshift, I needed to cast it to int. See the remarks of the class itself
// for more details.
uint tempInt = ((firstInt >> (int)thirdInt) ^ secondInt) & fourthInt;
firstInt ^= tempInt << (int)thirdInt;
secondInt ^= tempInt;
operationResults[0] = firstInt;
operationResults[1] = secondInt;
}
/// <summary>
/// Performs some operation on 3 uints. It's labeled HPERM_OP in the original source.
/// </summary>
/// <param name="firstInt">The first uint to use.</param>
/// <param name="secondInt">The second int to use.</param>
/// <param name="thirdInt">The third uint to use.</param>
/// <returns>An int that is the result of this operation.</returns>
private static uint HPermOperation(uint firstInt, int secondInt, uint thirdInt)
{
// The variable secondInt is always used to calculate the number at the right side of a
// bitshift. It is not used anywhere else, so I made the method parameter an int, to avoid
// unnecessary casting.
uint tempInt = ((firstInt << (16 - secondInt)) ^ firstInt) & thirdInt;
uint returnInt = firstInt ^ tempInt ^ (tempInt >> (16 - secondInt));
return returnInt;
}
/// <summary>
/// This method does some very complex bit manipulations.
/// </summary>
/// <param name="encryptionKey">The input data to use for the bit manipulations.</param>
/// <returns>m_desIterations * 2 number of uints that are the result of the manipulations.</returns>
private static uint[] SetDESKey(byte[] encryptionKey)
{
uint[] schedule = new uint[m_desIterations * 2];
uint firstInt = FourBytesToInt(encryptionKey, 0);
uint secondInt = FourBytesToInt(encryptionKey, 4);
uint[] operationResults = new uint[2];
PermOperation(secondInt, firstInt, 4, 0x0F0F0F0F, operationResults);
secondInt = operationResults[0];
firstInt = operationResults[1];
firstInt = HPermOperation(firstInt, -2, 0xCCCC0000);
secondInt = HPermOperation(secondInt, -2, 0xCCCC0000);
PermOperation(secondInt, firstInt, 1, 0x55555555, operationResults);
secondInt = operationResults[0];
firstInt = operationResults[1];
PermOperation(firstInt, secondInt, 8, 0x00FF00FF, operationResults);
firstInt = operationResults[0];
secondInt = operationResults[1];
PermOperation(secondInt, firstInt, 1, 0x55555555, operationResults);
secondInt = operationResults[0];
firstInt = operationResults[1];
secondInt = (((secondInt & 0xFF) << 16) | (secondInt & 0xFF00) |
((secondInt & 0xFF0000) >> 16) | ((firstInt & 0xF0000000) >> 4));
firstInt &= 0x0FFFFFFF;
bool needToShift;
uint firstSkbValue, secondSkbValue;
uint scheduleIndex = 0;
for(int index = 0; index < m_desIterations; index++)
{
needToShift = m_shifts[index];
if(needToShift)
{
firstInt = (firstInt >> 2) | (firstInt << 26);
secondInt = (secondInt >> 2) | (secondInt << 26);
}
else
{
firstInt = (firstInt >> 1) | (firstInt << 27);
secondInt = (secondInt >> 1) | (secondInt << 27);
}
firstInt &= 0x0FFFFFFF;
secondInt &= 0xFFFFFFF;
firstSkbValue = m_skb[0, firstInt & 0x3F] |
m_skb[1, ((firstInt >> 6) & 0x03) | ((firstInt >> 7) & 0x3C)] |
m_skb[2, ((firstInt >> 13) & 0x0F) | ((firstInt >> 14) & 0x30)] |
m_skb[3, ((firstInt >> 20) & 0x01) | ((firstInt >> 21) & 0x06) | ((firstInt >> 22) & 0x38)];
secondSkbValue = m_skb[4, secondInt & 0x3F] |
m_skb[5, ((secondInt >> 7) & 0x03) | ((secondInt >> 8) & 0x3C)] |
m_skb[6, (secondInt >> 15) & 0x3F] |
m_skb[7, ((secondInt >> 21) & 0x0F) | ((secondInt >> 22) & 0x30)];
schedule[scheduleIndex++] = ((secondSkbValue << 16) | (firstSkbValue & 0xFFFF)) & 0xFFFFFFFF;
firstSkbValue = ((firstSkbValue >> 16) | (secondSkbValue & 0xFFFF0000));
firstSkbValue = (firstSkbValue << 4) | (firstSkbValue >> 28);
schedule[scheduleIndex++] = firstSkbValue & 0xFFFFFFFF;
}
return schedule;
}
/// <summary>
/// This method does some bit manipulations.
/// </summary>
/// <param name="left">An input that is manipulated and then used for output.</param>
/// <param name="right">This is used for the bit manipulation.</param>
/// <param name="scheduleIndex">The index of an uint to use from the schedule array.</param>
/// <param name="firstSaltTranslator">The translated salt for the first salt character.</param>
/// <param name="secondSaltTranslator">The translated salt for the second salt character.</param>
/// <param name="schedule">The schedule arrray calculated before.</param>
/// <returns>The result of these manipulations.</returns>
private static uint DEncrypt(uint left, uint right, uint scheduleIndex, uint firstSaltTranslator, uint secondSaltTranslator, uint[] schedule)
{
uint firstInt, secondInt, thirdInt;
thirdInt = right ^ (right >> 16);
secondInt = thirdInt & firstSaltTranslator;
thirdInt = thirdInt & secondSaltTranslator;
secondInt = (secondInt ^ (secondInt << 16)) ^ right ^ schedule[scheduleIndex];
firstInt = (thirdInt ^ (thirdInt << 16)) ^ right ^ schedule[scheduleIndex+1];
firstInt = (firstInt >> 4) | (firstInt << 28);
left ^= (m_SPTranslationTable[1, firstInt & 0x3F] |
m_SPTranslationTable[3, (firstInt >> 8) & 0x3F] |
m_SPTranslationTable[5, (firstInt >> 16) & 0x3F] |
m_SPTranslationTable[7, (firstInt >> 24) & 0x3F] |
m_SPTranslationTable[0, secondInt & 0x3F] |
m_SPTranslationTable[2, (secondInt >> 8) & 0x3F] |
m_SPTranslationTable[4, (secondInt >> 16) & 0x3F] |
m_SPTranslationTable[6, (secondInt >> 24) & 0x3F]);
return left;
}
/// <summary>
/// Calculates two uints that are used to encrypt the password.
/// </summary>
/// <param name="schedule">The schedule table calculated earlier.</param>
/// <param name="firstSaltTranslator">The first translated salt character.</param>
/// <param name="secondSaltTranslator">The second translated salt character.</param>
/// <returns>2 uints in an array.</returns>
private static uint[] Body(uint[] schedule, uint firstSaltTranslator, uint secondSaltTranslator)
{
uint left = 0;
uint right = 0;
uint tempInt;
for(int index = 0; index < 25; index++)
{
for(uint secondIndex = 0; secondIndex < m_desIterations * 2; secondIndex += 4)
{
left = DEncrypt(left, right, secondIndex, firstSaltTranslator, secondSaltTranslator, schedule);
right = DEncrypt(right, left, secondIndex + 2, firstSaltTranslator, secondSaltTranslator, schedule);
}
tempInt = left;
left = right;
right = tempInt;
}
tempInt = right;
right = (left >> 1) | (left << 31);
left = (tempInt >> 1) | (tempInt << 31);
left &= 0xFFFFFFFF;
right &= 0xFFFFFFFF;
uint[] operationResults = new uint[2];
PermOperation(right, left, 1, 0x55555555, operationResults);
right = operationResults[0];
left = operationResults[1];
PermOperation(left, right, 8, 0x00FF00FF, operationResults);
left = operationResults[0];
right = operationResults[1];
PermOperation(right, left, 2, 0x33333333, operationResults);
right = operationResults[0];
left = operationResults[1];
PermOperation(left, right, 16, 0xFFFF, operationResults);
left = operationResults[0];
right = operationResults[1];
PermOperation(right, left, 4, 0x0F0F0F0F, operationResults);
right = operationResults[0];
left = operationResults[1];
uint[] singleOutputKey = new uint[2];
singleOutputKey[0] = left;
singleOutputKey[1] = right;
return singleOutputKey;
}
/// <summary>
/// Automatically generate the encryption salt (2 random printable characters for use in the encryption) and call the Crypt() method.
/// </summary>
/// <param name="textToEncrypt">The text that must be encrypted.</param>
/// <returns>The encrypted text.</returns>
public static string Crypt(string textToEncrypt)
{
Random randomGenerator = new Random();
int maxGeneratedNumber = m_encryptionSaltCharacters.Length;
int randomIndex;
StringBuilder encryptionSaltBuilder = new StringBuilder();
for(int index = 0; index < 2; index++)
{
randomIndex = randomGenerator.Next(maxGeneratedNumber);
encryptionSaltBuilder.Append(m_encryptionSaltCharacters[randomIndex]);
}
string encryptionSalt = encryptionSaltBuilder.ToString();
string encryptedString = Crypt(encryptionSalt, textToEncrypt);
return encryptedString;
}
/// <summary>
/// Encrypts the specified string using the Unix crypt algorithm.
/// </summary>
/// <param name="encryptionSalt">2 random printable characters that are used to randomize the encryption.</param>
/// <param name="textToEncrypt">The text that must be encrypted.</param>
/// <returns>The encrypted text.</returns>
public static string Crypt(string encryptionSalt, string textToEncrypt)
{
if(encryptionSalt==null) throw new ArgumentNullException("encryptionSalt");
if(textToEncrypt==null) throw new ArgumentNullException("textToEncrypt");
bool isSaltTooSmall = (encryptionSalt.Length < 2);
if(isSaltTooSmall)
{
throw new ArgumentException("The encryptionSalt must be 2 characters big.");
}
char firstSaltCharacter = encryptionSalt[0];
char secondSaltCharacter = encryptionSalt[1];
// Make sure the string builder is big enough AND filled with 13 characters (the length of the encrypted password).
// We will use the index operator to set them, but when the characters are not present, even though the string builder
// has enough capacity, it will throw an exception.
StringBuilder encryptionBuffer = new StringBuilder("*************");
encryptionBuffer[0] = firstSaltCharacter;
encryptionBuffer[1] = secondSaltCharacter;
// Use the ASCII value of the salt characters to lookup a number in the salt translation table.
uint firstSaltTranslator = m_saltTranslation[Convert.ToUInt32(firstSaltCharacter)];
uint secondSaltTranslator = m_saltTranslation[Convert.ToUInt32(secondSaltCharacter)] << 4;
// Build the first encryption key table by taking the ASCII value of every character in the text to encrypt and
// multiplying it by two. Note how the cast will not lose any information. The highest possible ASCII character
// in a password is the tilde (~), which has ASCII value 126, so the highest possible value after the
// multiplication would be 252.
byte[] encryptionKey = new byte[8];
for(int index = 0; index < encryptionKey.Length && index < textToEncrypt.Length; index++)
{
int shiftedCharacter = Convert.ToInt32(textToEncrypt[index]);
encryptionKey[index] = (byte)(shiftedCharacter << 1);
}
uint[] schedule = SetDESKey(encryptionKey);
uint[] singleOutputKey = Body(schedule, firstSaltTranslator, secondSaltTranslator);
byte[] binaryBuffer = new byte[9];
IntToFourBytes(singleOutputKey[0], binaryBuffer, 0);
IntToFourBytes(singleOutputKey[1], binaryBuffer, 4);
binaryBuffer[8] = 0;
uint binaryBufferIndex = 0;
uint passwordCharacter;
uint bitChecker = 0x80;
bool isAnyBitSet, bitCheckerOverflow;
for(int index = 2; index < 13; index++)
{
passwordCharacter = 0;
for(int secondIndex = 0; secondIndex < 6; secondIndex++)
{
passwordCharacter <<= 1;
isAnyBitSet = ((binaryBuffer[binaryBufferIndex] & bitChecker) != 0);
if(isAnyBitSet)
{
passwordCharacter |= 1;
}
bitChecker >>= 1;
bitCheckerOverflow = (bitChecker == 0);
if(bitCheckerOverflow)
{
binaryBufferIndex++;
bitChecker = 0x80;
}
// The original source had the line below, I moved it outside the compound signs, because it will overwrite the value
// a few times before incrementing the index. Where it is now it will be written only once.
// Just to be on the safe side, I keep the original line here, so I know where it originally was.
//encryptionBuffer[index] = Convert.ToChar(m_characterConversionTable[passwordCharacter]);
}
encryptionBuffer[index] = Convert.ToChar(m_characterConversionTable[passwordCharacter]);
}
return encryptionBuffer.ToString();
}
}
Decrypt Utils
///////////////////////////////////////////////////////////////////////////////////////////////
//
// This File is Part of the CallButler Open Source PBX (http://www.codeplex.com/callbutler
//
// Copyright (c) 2005-2008, Jim Heising
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation and/or
// other materials provided with the distribution.
//
// * Neither the name of Jim Heising nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific prior
// written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
///////////////////////////////////////////////////////////////////////////////////////////////
using System;
using System.Security.Cryptography;
using System.Text;
using System.Globalization;
using System.IO;
namespace WOSI.Utilities
{
/// <summary>
/// Summary description for CryptoUtils.
/// </summary>
public class CryptoUtils
{
private CryptoUtils()
{
//
// TODO: Add constructor logic here
//
}
// Decrypt a byte array into a byte array using a key and an IV
public static byte[] Decrypt(byte[] cipherData,
byte[] Key, byte[] IV)
{
try
{
// Create a MemoryStream that is going to accept the
// decrypted bytes
MemoryStream ms = new MemoryStream();
// Create a symmetric algorithm.
// We are going to use Rijndael because it is strong and
// available on all platforms.
// You can use other algorithms, to do so substitute the next
// line with something like
// TripleDES alg = TripleDES.Create();
Rijndael alg = Rijndael.Create();
// Now set the key and the IV.
// We need the IV (Initialization Vector) because the algorithm
// is operating in its default
// mode called CBC (Cipher Block Chaining). The IV is XORed with
// the first block (8 byte)
// of the data after it is decrypted, and then each decrypted
// block is XORed with the previous
// cipher block. This is done to make encryption more secure.
// There is also a mode called ECB which does not need an IV,
// but it is much less secure.
alg.Key = Key;
alg.IV = IV;
// Create a CryptoStream through which we are going to be
// pumping our data.
// CryptoStreamMode.Write means that we are going to be
// writing data to the stream
// and the output will be written in the MemoryStream
// we have provided.
CryptoStream cs = new CryptoStream(ms,
alg.CreateDecryptor(), CryptoStreamMode.Write);
// Write the data and make it do the decryption
cs.Write(cipherData, 0, cipherData.Length);
// Close the crypto stream (or do FlushFinalBlock).
// This will tell it that we have done our decryption
// and there is no more data coming in,
// and it is now a good time to remove the padding
// and finalize the decryption process.
cs.Close();
// Now get the decrypted data from the MemoryStream.
// Some people make a mistake of using GetBuffer() here,
// which is not the right way.
byte[] decryptedData = ms.ToArray();
return decryptedData;
}
catch
{
return null;
}
}
// Decrypt a string into a string using a password
// Uses Decrypt(byte[], byte[], byte[])
public static string Decrypt(string cipherText, string Password)
{
try
{
// First we need to turn the input string into a byte array.
// We presume that Base64 encoding was used
byte[] cipherBytes = Convert.FromBase64String(cipherText);
// Then, we need to turn the password into Key and IV
// We are using salt to make it harder to guess our key
// using a dictionary attack -
// trying to guess a password by enumerating all possible words.
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password,
new byte[] {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65,
0x64, 0x76, 0x65, 0x64, 0x65, 0x76});
// Now get the key/IV and do the decryption using
// the function that accepts byte arrays.
// Using PasswordDeriveBytes object we are first
// getting 32 bytes for the Key
// (the default Rijndael key length is 256bit = 32bytes)
// and then 16 bytes for the IV.
// IV should always be the block size, which is by
// default 16 bytes (128 bit) for Rijndael.
// If you are using DES/TripleDES/RC2 the block size is
// 8 bytes and so should be the IV size.
// You can also read KeySize/BlockSize properties off
// the algorithm to find out the sizes.
byte[] decryptedData = Decrypt(cipherBytes,
pdb.GetBytes(32), pdb.GetBytes(16));
// Now we need to turn the resulting byte array into a string.
// A common mistake would be to use an Encoding class for that.
// It does not work
// because not all byte values can be represented by characters.
// We are going to be using Base64 encoding that is
// designed exactly for what we are trying to do.
return System.Text.Encoding.Unicode.GetString(decryptedData);
}
catch
{
return null;
}
}
// Decrypt bytes into bytes using a password
// Uses Decrypt(byte[], byte[], byte[])
public static byte[] Decrypt(byte[] cipherData, string Password)
{
// We need to turn the password into Key and IV.
// We are using salt to make it harder to guess our key
// using a dictionary attack -
// trying to guess a password by enumerating all possible words.
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password,
new byte[] {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d,
0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76});
// Now get the key/IV and do the Decryption using the
//function that accepts byte arrays.
// Using PasswordDeriveBytes object we are first getting
// 32 bytes for the Key
// (the default Rijndael key length is 256bit = 32bytes)
// and then 16 bytes for the IV.
// IV should always be the block size, which is by default
// 16 bytes (128 bit) for Rijndael.
// If you are using DES/TripleDES/RC2 the block size is
// 8 bytes and so should be the IV size.
// You can also read KeySize/BlockSize properties off the
// algorithm to find out the sizes.
return Decrypt(cipherData, pdb.GetBytes(32), pdb.GetBytes(16));
}
// Decrypt a file into another file using a password
public static void Decrypt(string fileIn,
string fileOut, string Password)
{
try
{
// First we are going to open the file streams
FileStream fsIn = new FileStream(fileIn,
FileMode.Open, FileAccess.Read);
FileStream fsOut = new FileStream(fileOut,
FileMode.OpenOrCreate, FileAccess.Write);
// Then we are going to derive a Key and an IV from
// the Password and create an algorithm
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password,
new byte[] {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d,
0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76});
Rijndael alg = Rijndael.Create();
alg.Key = pdb.GetBytes(32);
alg.IV = pdb.GetBytes(16);
// Now create a crypto stream through which we are going
// to be pumping data.
// Our fileOut is going to be receiving the Decrypted bytes.
CryptoStream cs = new CryptoStream(fsOut,
alg.CreateDecryptor(), CryptoStreamMode.Write);
// Now will will initialize a buffer and will be
// processing the input file in chunks.
// This is done to avoid reading the whole file (which can be
// huge) into memory.
int bufferLen = 4096;
byte[] buffer = new byte[bufferLen];
int bytesRead;
do
{
// read a chunk of data from the input file
bytesRead = fsIn.Read(buffer, 0, bufferLen);
// Decrypt it
cs.Write(buffer, 0, bytesRead);
} while (bytesRead != 0);
// close everything
cs.Close(); // this will also close the unrelying fsOut stream
fsIn.Close();
}
catch
{
}
}
}
}
Encrypt Utils
///////////////////////////////////////////////////////////////////////////////////////////////
//
// This File is Part of the CallButler Open Source PBX (http://www.codeplex.com/callbutler
//
// Copyright (c) 2005-2008, Jim Heising
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation and/or
// other materials provided with the distribution.
//
// * Neither the name of Jim Heising nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific prior
// written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
///////////////////////////////////////////////////////////////////////////////////////////////
using System;
using System.Security.Cryptography;
using System.Text;
using System.Globalization;
using System.IO;
namespace WOSI.Utilities
{
/// <summary>
/// Summary description for CryptoUtils.
/// </summary>
public class CryptoUtils
{
public static byte[] Encrypt(byte[] clearData, byte[] Key, byte[] IV)
{
// Create a MemoryStream to accept the encrypted bytes
MemoryStream ms = new MemoryStream();
// Create a symmetric algorithm.
// We are going to use Rijndael because it is strong and
// available on all platforms.
// You can use other algorithms, to do so substitute the
// next line with something like
// TripleDES alg = TripleDES.Create();
Rijndael alg = Rijndael.Create();
// Now set the key and the IV.
// We need the IV (Initialization Vector) because
// the algorithm is operating in its default
// mode called CBC (Cipher Block Chaining).
// The IV is XORed with the first block (8 byte)
// of the data before it is encrypted, and then each
// encrypted block is XORed with the
// following block of plaintext.
// This is done to make encryption more secure.
// There is also a mode called ECB which does not need an IV,
// but it is much less secure.
alg.Key = Key;
alg.IV = IV;
// Create a CryptoStream through which we are going to be
// pumping our data.
// CryptoStreamMode.Write means that we are going to be
// writing data to the stream and the output will be written
// in the MemoryStream we have provided.
CryptoStream cs = new CryptoStream(ms,
alg.CreateEncryptor(), CryptoStreamMode.Write);
// Write the data and make it do the encryption
cs.Write(clearData, 0, clearData.Length);
// Close the crypto stream (or do FlushFinalBlock).
// This will tell it that we have done our encryption and
// there is no more data coming in,
// and it is now a good time to apply the padding and
// finalize the encryption process.
cs.Close();
// Now get the encrypted data from the MemoryStream.
// Some people make a mistake of using GetBuffer() here,
// which is not the right way.
byte[] encryptedData = ms.ToArray();
return encryptedData;
}
// Encrypt a string into a string using a password
// Uses Encrypt(byte[], byte[], byte[])
public static string Encrypt(string clearText, string Password)
{
// First we need to turn the input string into a byte array.
byte[] clearBytes =
System.Text.Encoding.Unicode.GetBytes(clearText);
// Then, we need to turn the password into Key and IV
// We are using salt to make it harder to guess our key
// using a dictionary attack -
// trying to guess a password by enumerating all possible words.
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password,
new byte[] {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d,
0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76});
// Now get the key/IV and do the encryption using the
// function that accepts byte arrays.
// Using PasswordDeriveBytes object we are first getting
// 32 bytes for the Key
// (the default Rijndael key length is 256bit = 32bytes)
// and then 16 bytes for the IV.
// IV should always be the block size, which is by default
// 16 bytes (128 bit) for Rijndael.
// If you are using DES/TripleDES/RC2 the block size is
// 8 bytes and so should be the IV size.
// You can also read KeySize/BlockSize properties off
// the algorithm to find out the sizes.
byte[] encryptedData = Encrypt(clearBytes,
pdb.GetBytes(32), pdb.GetBytes(16));
// Now we need to turn the resulting byte array into a string.
// A common mistake would be to use an Encoding class for that.
//It does not work because not all byte values can be
// represented by characters.
// We are going to be using Base64 encoding that is designed
//exactly for what we are trying to do.
return Convert.ToBase64String(encryptedData);
}
// Encrypt bytes into bytes using a password
// Uses Encrypt(byte[], byte[], byte[])
public static byte[] Encrypt(byte[] clearData, string Password)
{
// We need to turn the password into Key and IV.
// We are using salt to make it harder to guess our key
// using a dictionary attack -
// trying to guess a password by enumerating all possible words.
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password,
new byte[] {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d,
0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76});
// Now get the key/IV and do the encryption using the function
// that accepts byte arrays.
// Using PasswordDeriveBytes object we are first getting
// 32 bytes for the Key
// (the default Rijndael key length is 256bit = 32bytes)
// and then 16 bytes for the IV.
// IV should always be the block size, which is by default
// 16 bytes (128 bit) for Rijndael.
// If you are using DES/TripleDES/RC2 the block size is 8
// bytes and so should be the IV size.
// You can also read KeySize/BlockSize properties off the
// algorithm to find out the sizes.
return Encrypt(clearData, pdb.GetBytes(32), pdb.GetBytes(16));
}
// Encrypt a file into another file using a password
public static void Encrypt(string fileIn,
string fileOut, string Password)
{
// First we are going to open the file streams
FileStream fsIn = new FileStream(fileIn,
FileMode.Open, FileAccess.Read);
FileStream fsOut = new FileStream(fileOut,
FileMode.OpenOrCreate, FileAccess.Write);
// Then we are going to derive a Key and an IV from the
// Password and create an algorithm
PasswordDeriveBytes pdb = new PasswordDeriveBytes(Password,
new byte[] {0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d,
0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76});
Rijndael alg = Rijndael.Create();
alg.Key = pdb.GetBytes(32);
alg.IV = pdb.GetBytes(16);
// Now create a crypto stream through which we are going
// to be pumping data.
// Our fileOut is going to be receiving the encrypted bytes.
CryptoStream cs = new CryptoStream(fsOut,
alg.CreateEncryptor(), CryptoStreamMode.Write);
// Now will will initialize a buffer and will be processing
// the input file in chunks.
// This is done to avoid reading the whole file (which can
// be huge) into memory.
int bufferLen = 4096;
byte[] buffer = new byte[bufferLen];
int bytesRead;
do
{
// read a chunk of data from the input file
bytesRead = fsIn.Read(buffer, 0, bufferLen);
// encrypt it
cs.Write(buffer, 0, bytesRead);
} while(bytesRead != 0);
// close everything
// this will also close the unrelying fsOut stream
cs.Close();
fsIn.Close();
}
}
}
Do CRC32 hashing.
/* --------------------------------------------------------------------------
*
* License
*
* The contents of this file are subject to the Jabber Open Source License
* Version 1.0 (the "License"). You may not copy or use this file, in either
* source code or executable form, except in compliance with the License. You
* may obtain a copy of the License at http://www.jabber.com/license/ or at
* http://www.opensource.org/.
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* Copyrights
*
* Portions created by or assigned to Cursive Systems, Inc. are
* Copyright (c) 2002 Cursive Systems, Inc. All Rights Reserved. Contact
* information for Cursive Systems, Inc. is available at http://www.cursive.net/.
*
* Portions Copyright (c) 2002 Joe Hildebrand.
*
* Acknowledgements
*
* Special thanks to the Jabber Open Source Contributors for their
* suggestions and support of Jabber.
*
* --------------------------------------------------------------------------*/
using System;
using System.Security.Cryptography;
namespace bedrock.util
{
/// <summary>
/// Do CRC32 hashing. Note: just use SHA1, or MD5, from System.Security.Cryptography.
/// </summary>
public class CRC32
{
private const int WIDTH = 32;
private const ulong POLY = 0x04C11DB7;
private const ulong INIT = 0xFFFFFFFF;
private const ulong XOROUT = 0xFFFFFFFF;
private static readonly uint[] crctable =
{
0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA,
0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,
0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940,
0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116,
0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A,
0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818,
0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C,
0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086,
0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4,
0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE,
0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252,
0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60,
0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04,
0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A,
0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E,
0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0,
0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6,
0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
};
/// <summary>
/// Hash a block of bytes.
/// </summary>
/// <param name="block"></param>
/// <returns></returns>
public static uint compute(byte[] block)
{
ulong c = INIT;
int len = block.Length;
int i = 0;
while (len-- > 0)
{
c = crctable[(c ^ block[i++]) & 0xFFL] ^ (c >> 8);
}
return (uint)(c ^ XOROUT);
}
/// <summary>
/// Hash a string
/// </summary>
/// <param name="s"></param>
/// <returns></returns>
public static uint compute(string s)
{
return compute(System.Text.Encoding.ASCII.GetBytes(s));
}
}
}
Calculates a 32 bit Cyclic Redundancy Checksum (CRC) using the same polynomial used by Zip.
// Crc32.cs
//
// Implements the CRC algorithm, which is used in zip files. The zip format calls for
// the zipfile to contain a CRC for the unencrypted byte stream of each file.
//
// It is based on example source code published at
// http://www.vbaccelerator.com/home/net/code/libraries/CRC32/Crc32_zip_CRC32_CRC32_cs.asp
//
// This implementation adds a tweak of that code for use within zip creation. While
// computing the CRC we also compress the byte stream, in the same read loop. This
// avoids the need to read through the uncompressed stream twice - once to computer CRC
// and another time to compress.
//
//
// Thu, 30 Mar 2006 13:58
//
using System;
namespace ionic.utils.zip
{
/// <summary>
/// Calculates a 32bit Cyclic Redundancy Checksum (CRC) using the
/// same polynomial used by Zip.
/// </summary>
public class CRC32
{
private UInt32[] crc32Table;
private const int BUFFER_SIZE = 8192;
private Int32 _TotalBytesRead = 0;
public Int32 TotalBytesRead
{
get
{
return _TotalBytesRead;
}
}
/// <summary>
/// Returns the CRC32 for the specified stream.
/// </summary>
/// <param name="input">The stream over which to calculate the CRC32</param>
/// <returns>the CRC32 calculation</returns>
public UInt32 GetCrc32(System.IO.Stream input)
{
return GetCrc32AndCopy(input, null);
}
/// <summary>
/// Returns the CRC32 for the specified stream, and writes the input into the output stream.
/// </summary>
/// <param name="input">The stream over which to calculate the CRC32</param>
/// <param name="output">The stream into which to deflate the input</param>
/// <returns>the CRC32 calculation</returns>
public UInt32 GetCrc32AndCopy(System.IO.Stream input, System.IO.Stream output)
{
unchecked
{
UInt32 crc32Result;
crc32Result = 0xFFFFFFFF;
byte[] buffer = new byte[BUFFER_SIZE];
int readSize = BUFFER_SIZE;
_TotalBytesRead = 0;
int count = input.Read(buffer, 0, readSize);
if (output != null) output.Write(buffer, 0, count);
_TotalBytesRead += count;
while (count > 0)
{
for (int i = 0; i < count; i++)
{
crc32Result = ((crc32Result) >> 8) ^ crc32Table[(buffer[i]) ^ ((crc32Result) & 0x000000FF)];
}
count = input.Read(buffer, 0, readSize);
if (output != null) output.Write(buffer, 0, count);
_TotalBytesRead += count;
}
return ~crc32Result;
}
}
/// <summary>
/// Construct an instance of the CRC32 class, pre-initialising the table
/// for speed of lookup.
/// </summary>
public CRC32()
{
unchecked
{
// This is the official polynomial used by CRC32 in PKZip.
// Often the polynomial is shown reversed as 0x04C11DB7.
UInt32 dwPolynomial = 0xEDB88320;
UInt32 i, j;
crc32Table = new UInt32[256];
UInt32 dwCrc;
for (i = 0; i < 256; i++)
{
dwCrc = i;
for (j = 8; j > 0; j--)
{
if ((dwCrc & 1) == 1)
{
dwCrc = (dwCrc >> 1) ^ dwPolynomial;
}
else
{
dwCrc >>= 1;
}
}
crc32Table[i] = dwCrc;
}
}
}
}
}
Generate a table for a byte-wise 32-bit CRC calculation on the polynomial: x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
// CRC32.cs - Computes CRC32 data checksum of a data stream
// Copyright (C) 2001 Mike Krueger
//
// This file was translated from java, it was part of the GNU Classpath
// Copyright (C) 1999, 2000, 2001 Free Software Foundation, Inc.
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// Linking this library statically or dynamically with other modules is
// making a combined work based on this library. Thus, the terms and
// conditions of the GNU General Public License cover the whole
// combination.
//
// As a special exception, the copyright holders of this library give you
// permission to link this library with independent modules to produce an
// executable, regardless of the license terms of these independent
// modules, and to copy and distribute the resulting executable under
// terms of your choice, provided that you also meet, for each linked
// independent module, the terms and conditions of the license of that
// module. An independent module is a module which is not derived from
// or based on this library. If you modify this library, you may extend
// this exception to your version of the library, but you are not
// obligated to do so. If you do not wish to do so, delete this
// exception statement from your version.
using System;
namespace ICSharpCode.SharpZipLib.Checksums
{
/// <summary>
/// Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
/// x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
///
/// Polynomials over GF(2) are represented in binary, one bit per coefficient,
/// with the lowest powers in the most significant bit. Then adding polynomials
/// is just exclusive-or, and multiplying a polynomial by x is a right shift by
/// one. If we call the above polynomial p, and represent a byte as the
/// polynomial q, also with the lowest power in the most significant bit (so the
/// byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
/// where a mod b means the remainder after dividing a by b.
///
/// This calculation is done using the shift-register method of multiplying and
/// taking the remainder. The register is initialized to zero, and for each
/// incoming bit, x^32 is added mod p to the register if the bit is a one (where
/// x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
/// x (which is shifting right by one and adding x^32 mod p if the bit shifted
/// out is a one). We start with the highest power (least significant bit) of
/// q and repeat for all eight bits of q.
///
/// The table is simply the CRC of all possible eight bit values. This is all
/// the information needed to generate CRC's on data a byte at a time for all
/// combinations of CRC register values and incoming bytes.
/// </summary>
public sealed class Crc32
{
const uint CrcSeed = 0xFFFFFFFF;
readonly static uint[] CrcTable = new uint[] {
0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419,
0x706AF48F, 0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4,
0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07,
0x90BF1D91, 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 0x136C9856,
0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9,
0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4,
0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3,
0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 0x26D930AC, 0x51DE003A,
0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599,
0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190,
0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F,
0x9FBFE4A5, 0xE8B8D433, 0x7807C9A2, 0x0F00F934, 0x9609A88E,
0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED,
0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950,
0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3,
0xFBD44C65, 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A,
0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5,
0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA, 0xBE0B1010,
0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17,
0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6,
0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615,
0x73DC1683, 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 0xF00F9344,
0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB,
0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A,
0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1,
0xA6BC5767, 0x3FB506DD, 0x48B2364B, 0xD80D2BDA, 0xAF0A1B4C,
0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF,
0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE,
0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31,
0x2CD99E8B, 0x5BDEAE1D, 0x9B64C2B0, 0xEC63F226, 0x756AA39C,
0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B,
0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242,
0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1,
0x18B74777, 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 0xA00AE278,
0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7,
0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66,
0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605,
0xCDD70693, 0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8,
0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B,
0x2D02EF8D
};
internal static uint ComputeCrc32(uint oldCrc, byte value)
{
return (uint)(Crc32.CrcTable[(oldCrc ^ value) & 0xFF] ^ (oldCrc >> 8));
}
/// <summary>
/// The crc data checksum so far.
/// </summary>
uint crc;
/// <summary>
/// Returns the CRC32 data checksum computed so far.
/// </summary>
public long Value {
get {
return (long)crc;
}
set {
crc = (uint)value;
}
}
/// <summary>
/// Resets the CRC32 data checksum as if no update was ever called.
/// </summary>
public void Reset()
{
crc = 0;
}
/// <summary>
/// Updates the checksum with the int bval.
/// </summary>
/// <param name = "value">
/// the byte is taken as the lower 8 bits of value
/// </param>
public void Update(int value)
{
crc ^= CrcSeed;
crc = CrcTable[(crc ^ value) & 0xFF] ^ (crc >> 8);
crc ^= CrcSeed;
}
/// <summary>
/// Updates the checksum with the bytes taken from the array.
/// </summary>
/// <param name="buffer">
/// buffer an array of bytes
/// </param>
public void Update(byte[] buffer)
{
if (buffer == null) {
throw new ArgumentNullException("buffer");
}
Update(buffer, 0, buffer.Length);
}
/// <summary>
/// Adds the byte array to the data checksum.
/// </summary>
/// <param name = "buffer">
/// The buffer which contains the data
/// </param>
/// <param name = "offset">
/// The offset in the buffer where the data starts
/// </param>
/// <param name = "count">
/// The number of data bytes to update the CRC with.
/// </param>
public void Update(byte[] buffer, int offset, int count)
{
if (buffer == null) {
throw new ArgumentNullException("buffer");
}
if ( count < 0 ) {
#if NETCF_1_0
throw new ArgumentOutOfRangeException("count");
#else
throw new ArgumentOutOfRangeException("count", "Count cannot be less than zero");
#endif
}
if (offset < 0 || offset + count > buffer.Length) {
throw new ArgumentOutOfRangeException("offset");
}
crc ^= CrcSeed;
while (--count >= 0) {
crc = CrcTable[(crc ^ buffer[offset++]) & 0xFF] ^ (crc >> 8);
}
crc ^= CrcSeed;
}
}
}