MD5加密算法(16位,32位)的C#的实现

以下为MD5算法用c#的实现
//MD5.cs
//MD5 16-bit,32-bits algorithm implemented in C#

using System;
using System.Text;

namespace Encrypter
{
///

/// Summary description for MD5.
///

public class MD5
{
const int BITS_TO_A_BYTE = 8;
const int BYTES_TO_A_WORD = 4;
const int BITS_TO_A_WORD = 32;
private static long[] m_lOnBits = new long[30 + 1];
private static long[] m_l2Power = new long[30 + 1];

private static long LShift(long lValue, long iShiftBits)
{
long LShift = 0;
if (iShiftBits == 0)
{
LShift = lValue;
return LShift;
}
else
{
if( iShiftBits == 31)
{
if (Convert.ToBoolean(lValue & 1))
{
LShift = 0x80000000;
}
else
{
LShift = 0;
}
return LShift;
}
else
{
if( iShiftBits < 0 || iShiftBits > 31)
{
// Err.Raise 6;
}
}
}

if (Convert.ToBoolean((lValue & m_l2Power[31 - iShiftBits])))
{
LShift = ((lValue & m_lOnBits[31 - (iShiftBits + 1)]) * m_l2Power[iShiftBits]) | 0x80000000;
}
else
{
LShift = ((lValue & m_lOnBits[31 - iShiftBits]) * m_l2Power[iShiftBits]);
}

return LShift;
}

private static long RShift(long lValue, long iShiftBits)
{
long RShift = 0;
if (iShiftBits == 0)
{
RShift = lValue;
return RShift;
}
else
{
if( iShiftBits == 31)
{
if (Convert.ToBoolean(lValue & 0x80000000))
{
RShift = 1;
}
else
{
RShift = 0;
}
return RShift;
}
else
{
if( iShiftBits < 0 || iShiftBits > 31)
{
// Err.Raise 6;
}
}
}

RShift = (lValue & 0x7FFFFFFE) / m_l2Power[iShiftBits];

if (Convert.ToBoolean((lValue & 0x80000000)))
{
RShift = (RShift | (0x40000000 / m_l2Power[iShiftBits - 1]));
}

return RShift;
}

private static long RotateLeft(long lValue, long iShiftBits)
{
long RotateLeft = 0;
RotateLeft = LShift(lValue, iShiftBits) | RShift(lValue, (32 - iShiftBits));
return RotateLeft;
}

private static long AddUnsigned(long lX, long lY)
{
long AddUnsigned = 0;
long lX4 = 0;
long lY4 = 0;
long lX8 = 0;
long lY8 = 0;
long lResult = 0;

lX8 = lX & 0x80000000;
lY8 = lY & 0x80000000;
lX4 = lX & 0x40000000;
lY4 = lY & 0x40000000;

lResult = (lX & 0x3FFFFFFF) + (lY & 0x3FFFFFFF);
if (Convert.ToBoolean(lX4 & lY4))
{
lResult = lResult ^ 0x80000000 ^ lX8 ^ lY8;
}
else if( Convert.ToBoolean(lX4 | lY4))
{
if (Convert.ToBoolean(lResult & 0x40000000))
{
lResult = lResult ^ 0xC0000000 ^ lX8 ^ lY8;
}
else
{
lResult = lResult ^ 0x40000000 ^ lX8 ^ lY8;
}
}
else
{
lResult = lResu

lt ^ lX8 ^ lY8;
}
AddUnsigned = lResult;
return AddUnsigned;
}

private static long md5_F(long x, long y, long z)
{
long md5_F = 0;
md5_F = (x & y) | (( ~x) & z);
return md5_F;
}

private static long md5_G(long x, long y, long z)
{
long md5_G = 0;
md5_G = (x & z) | (y & ( ~z));
return md5_G;
}

private static long md5_H(long x, long y, long z)
{
long md5_H = 0;
md5_H = (x ^ y ^ z);
return md5_H;
}

private static long md5_I(long x, long y, long z)
{
long md5_I = 0;
md5_I = (y ^ (x | (~z)));
return md5_I;
}

private static void md5_FF(ref long a, long b, long c, long d, long x, long s, long ac)
{
a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_F(b, c, d), x), ac));
a = RotateLeft(a, s);
a = AddUnsigned(a, b);
}

private static void md5_GG(ref long a, long b, long c, long d, long x, long s, long ac)
{
a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_G(b, c, d), x), ac));
a = RotateLeft(a, s);
a = AddUnsigned(a, b);
}

private static void md5_HH(ref long a, long b, long c, long d, long x, long s, long ac)
{
a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_H(b, c, d), x), ac));
a = RotateLeft(a, s);
a = AddUnsigned(a, b);
}

private static void md5_II(ref long a, long b, long c, long d, long x, long s, long ac)
{
a = AddUnsigned(a, AddUnsigned(AddUnsigned(md5_I(b, c, d), x), ac));
a = RotateLeft(a, s);
a = AddUnsigned(a, b);
}

private static long[] ConvertToWordArray(string sMessage)
{
long[] ConvertToWordArray = null;
int lMessageLength = 0;
int lNumberOfWords = 0;
long[] lWordArray = null;
int lBytePosition = 0;
int lByteCount = 0;
int lWordCount = 0;

const int MODULUS_BITS = 512;
const int CONGRUENT_BITS = 448;

lMessageLength = sMessage.Length;
lNumberOfWords = (((lMessageLength + ((MODULUS_BITS - CONGRUENT_BITS) / BITS_TO_A_BYTE)) / (MODULUS_BITS / BITS_TO_A_BYTE)) + 1) * (MODULUS_BITS / BITS_TO_A_WORD);
lWordArray = new long[lNumberOfWords];

lBytePosition = 0;
lByteCount = 0;

while(lByteCount < lMessageLength)
{
lWordCount = lByteCount / BYTES_TO_A_WORD;
lBytePosition = (lByteCount % BYTES_TO_A_WORD) * BITS_TO_A_BYTE;
lWordArray[lWordCount] = lWordArray[lWordCount] | LShift(Convert.ToByte(sMessage.Substring(lByteCount, 1).ToCharArray()[0]), lBytePosition);
lByteCount = lByteCount + 1;
}

lWordCount = lByteCount / BYTES_TO_A_WORD;
lBytePosition = (lByteCount % BYTES_TO_A_WORD) * BITS_TO_A_BYTE;
lWordArray[lWordCount] = lWordArray[lWordCount] | LShift(0x80, lBytePosition);
lWordArray[lNumberOfWords - 2] = LShift(lMessageLength, 3);
lWordArray[lNumberOfWords - 1] = RShift(lMessageLength, 29);
ConvertToWordArray = lWordArray;

return ConvertToWordArray;

}

private static string WordToHex(long lValue)
{
string WordToHex = "";
long lByte = 0;
int lCount = 0;
for(lCount = 0; lCount <= 3; lCount++)
{
lByte = RShift(lValue, lCount * BITS_TO_A_BYTE) & m_lOnBits[BITS_TO_A_BYTE - 1];
WordToHex = WordToHex + (("0" + ToHex(lByte)).Substring(("0" + ToHex(lByte)).Length - 2));
}
return WordToHex;
}

private static string ToHex(long dec)
{
string strhex = "";
while(dec > 0)
{
strhex = tohex(dec % 16) + strhex;
dec = dec / 16;
}
return strhex;
}

private static string tohex(long hex)
{
string strhex = "";
switch(hex)
{
case 10: strhex = "a"; break;
case 11: strhex = "b"; break;
case 12: strhex = "c"; break;
case 13: strhex = "d"; break;
case 14: strhex = "e"; break;
case 15: strhex = "f"; break;
default : strhex = hex.ToString(); break;
}
return strhex;
}

public static string Encrypt(string sMessage, int stype)
{
string MD5 = "";

for(int i=0; i<=30; i++)
{
m_lOnBits[i] = Convert.ToInt64(Math.Pow(2, i+1) -1);
m_l2Power[i] = Convert.ToInt64(Math.Pow(2, i));
}

long[] x = null;
int k = 0;
long AA = 0;
long BB = 0;
long CC = 0;
long DD = 0;
long a = 0;
long b = 0;
long c = 0;
long d = 0;

const int S11 = 7;
const int S12 = 12;
const int S13 = 17;
const int S14 = 22;
const int S21 = 5;
const int S22 = 9;
const int S23 = 14;
const int S24 = 20;
const int S31 = 4;
const int S32 = 11;
const int S33 = 16;
const int S34 = 23;
const int S41 = 6;
const int S42 = 10;
const int S43 = 15;
const int S44 = 21;

x = ConvertToWordArray(sMessage);

a = 0x67452301;
b = 0xEFCDAB89;
c = 0x98BADCFE;
d = 0x10325476;

for(k = 0; k < x.Length; k += 16)
{
AA = a;
BB = b;
CC = c;
DD = d;

md5_FF(ref a, b, c, d, x[k + 0], S11, 0xD76AA478);
md5_FF(ref d, a, b, c, x[k + 1], S12, 0xE8C7B756);
md5_FF(ref c, d, a, b, x[k + 2], S13, 0x242070DB);
md5_FF(ref b, c, d, a, x[k + 3], S14, 0xC1BDCEEE);
md5_FF(ref a, b, c, d, x[k + 4], S11, 0xF57C0FAF);
md5_FF(ref d, a, b, c, x[k + 5], S12, 0x4787C62A);
md5_FF(ref c, d, a, b, x[k + 6], S13, 0xA8304613);
md5_FF(ref b, c, d, a, x[k + 7], S14, 0xFD469501);
md5_FF(ref a, b, c, d, x[k + 8], S11, 0x698098D8);
md5_FF(ref d, a, b, c, x[k + 9], S12, 0x8B44F7AF);
md5_FF(ref c, d, a, b, x[k + 10], S13, 0xFFFF5BB1);
md5_FF(ref b, c, d, a, x[k + 11], S14, 0x895CD7BE);
md5_FF(ref a, b, c, d, x[k + 12], S11, 0x6B901122);
md5_FF(ref d, a, b, c, x[k + 13], S12, 0xFD987193);
md5_FF(ref c, d, a, b, x[k + 14], S13, 0xA679438E);
md5_FF(ref b, c, d, a, x[k + 15], S14, 0x49B40821);
md5_GG(ref a, b, c,

d, x[k + 1], S21, 0xF61E2562);
md5_GG(ref d, a, b, c, x[k + 6], S22, 0xC040B340);
md5_GG(ref c, d, a, b, x[k + 11], S23, 0x265E5A51);
md5_GG(ref b, c, d, a, x[k + 0], S24, 0xE9B6C7AA);
md5_GG(ref a, b, c, d, x[k + 5], S21, 0xD62F105D);
md5_GG(ref d, a, b, c, x[k + 10], S22, 0x2441453);
md5_GG(ref c, d, a, b, x[k + 15], S23, 0xD8A1E681);
md5_GG(ref b, c, d, a, x[k + 4], S24, 0xE7D3FBC8);
md5_GG(ref a, b, c, d, x[k + 9], S21, 0x21E1CDE6);
md5_GG(ref d, a, b, c, x[k + 14], S22, 0xC33707D6);
md5_GG(ref c, d, a, b, x[k + 3], S23, 0xF4D50D87);
md5_GG(ref b, c, d, a, x[k + 8], S24, 0x455A14ED);
md5_GG(ref a, b, c, d, x[k + 13], S21, 0xA9E3E905);
md5_GG(ref d, a, b, c, x[k + 2], S22, 0xFCEFA3F8);
md5_GG(ref c, d, a, b, x[k + 7], S23, 0x676F02D9);
md5_GG(ref b, c, d, a, x[k + 12], S24, 0x8D2A4C8A);
md5_HH(ref a, b, c, d, x[k + 5], S31, 0xFFFA3942);
md5_HH(ref d, a, b, c, x[k + 8], S32, 0x8771F681);
md5_HH(ref c, d, a, b, x[k + 11], S33, 0x6D9D6122);
md5_HH(ref b, c, d, a, x[k + 14], S34, 0xFDE5380C);
md5_HH(ref a, b, c, d, x[k + 1], S31, 0xA4BEEA44);
md5_HH(ref d, a, b, c, x[k + 4], S32, 0x4BDECFA9);
md5_HH(ref c, d, a, b, x[k + 7], S33, 0xF6BB4B60);
md5_HH(ref b, c, d, a, x[k + 10], S34, 0xBEBFBC70);
md5_HH(ref a, b, c, d, x[k + 13], S31, 0x289B7EC6);
md5_HH(ref d, a, b, c, x[k + 0], S32, 0xEAA127FA);
md5_HH(ref c, d, a, b, x[k + 3], S33, 0xD4EF3085);
md5_HH(ref b, c, d, a, x[k + 6], S34, 0x4881D05);
md5_HH(ref a, b, c, d, x[k + 9], S31, 0xD9D4D039);
md5_HH(ref d, a, b, c, x[k + 12], S32, 0xE6DB99E5);
md5_HH(ref c, d, a, b, x[k + 15], S33, 0x1FA27CF8);
md5_HH(ref b, c, d, a, x[k + 2], S34, 0xC4AC5665);
md5_II(ref a, b, c, d, x[k + 0], S41, 0xF4292244);
md5_II(ref d, a, b, c, x[k + 7], S42, 0x432AFF97);
md5_II(ref c, d, a, b, x[k + 14], S43, 0xAB9423A7);
md5_II(ref b, c, d, a, x[k + 5], S44, 0xFC93A039);
md5_II(ref a, b, c, d, x[k + 12], S41, 0x655B59C3);
md5_II(ref d, a, b, c, x[k + 3], S42, 0x8F0CCC92);
md5_II(ref c, d, a, b, x[k + 10], S43, 0xFFEFF47D);
md5_II(ref b, c, d, a, x[k + 1], S44, 0x85845DD1);
md5_II(ref a, b, c, d, x[k + 8], S41, 0x6FA87E4F);
md5_II(ref d, a, b, c, x[k + 15], S42, 0xFE2CE6E0);
md5_II(ref c, d, a, b, x[k + 6], S43, 0xA3014314);
md5_II(ref b, c, d, a, x[k + 13], S44, 0x4E0811A1);
md5_II(ref a, b, c, d, x[k + 4], S41, 0xF7537E82);
md5_II(ref d, a, b, c, x[k + 11], S42, 0xBD3AF235);
md5_II(ref c, d, a, b, x[k + 2], S43, 0x2AD7D2BB);
md5_II(ref b, c, d, a, x[k + 9], S44, 0xEB86D391);

a = AddUnsigned(a, AA);
b = AddUnsigned(b, BB);
c = AddUnsigned(c, CC);
d = AddUnsigned(d, DD);
}

if (stype == 32)
{
MD5 = ((((WordToHex(a)) + (WordToHex(b))) + (WordToHex(c))) + (WordToHex(d))).ToLower();
}
else

{
MD5 = ((WordToHex(b)) + (WordToHex(c))).ToLower();
}
return MD5;
}
}
}