maui-linux/Xamarin.Forms.Platform.WP8/MD5CryptoServiceProvider.cs

444 строки
10 KiB
C#

using System;
namespace Xamarin.Forms.Platform.WinPhone
{
internal sealed class MD5CryptoServiceProvider : MD5
{
const int BlockSizeBytes = 64;
static readonly uint[] K =
{
0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee, 0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501, 0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be, 0x6b901122,
0xfd987193, 0xa679438e, 0x49b40821, 0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa, 0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8, 0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed, 0xa9e3e905,
0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a, 0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c, 0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70, 0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05, 0xd9d4d039,
0xe6db99e5, 0x1fa27cf8, 0xc4ac5665, 0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039, 0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1, 0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1, 0xf7537e82,
0xbd3af235, 0x2ad7d2bb, 0xeb86d391
};
uint[] _buff;
ulong _count;
uint[] _h;
byte[] _processingBuffer; // Used to start data when passed less than a block worth.
int _processingBufferCount; // Counts how much data we have stored that still needs processed.
public MD5CryptoServiceProvider()
{
_h = new uint[4];
_buff = new uint[16];
_processingBuffer = new byte[BlockSizeBytes];
Initialize();
}
public override void Initialize()
{
_count = 0;
_processingBufferCount = 0;
_h[0] = 0x67452301;
_h[1] = 0xefcdab89;
_h[2] = 0x98badcfe;
_h[3] = 0x10325476;
}
protected override void Dispose(bool disposing)
{
if (_processingBuffer != null)
{
Array.Clear(_processingBuffer, 0, _processingBuffer.Length);
_processingBuffer = null;
}
if (_h != null)
{
Array.Clear(_h, 0, _h.Length);
_h = null;
}
if (_buff != null)
{
Array.Clear(_buff, 0, _buff.Length);
_buff = null;
}
}
protected override void HashCore(byte[] rgb, int ibStart, int cbSize)
{
int i;
State = 1;
if (_processingBufferCount != 0)
{
if (cbSize < BlockSizeBytes - _processingBufferCount)
{
Buffer.BlockCopy(rgb, ibStart, _processingBuffer, _processingBufferCount, cbSize);
_processingBufferCount += cbSize;
return;
}
i = BlockSizeBytes - _processingBufferCount;
Buffer.BlockCopy(rgb, ibStart, _processingBuffer, _processingBufferCount, i);
ProcessBlock(_processingBuffer, 0);
_processingBufferCount = 0;
ibStart += i;
cbSize -= i;
}
for (i = 0; i < cbSize - cbSize % BlockSizeBytes; i += BlockSizeBytes)
ProcessBlock(rgb, ibStart + i);
if (cbSize % BlockSizeBytes != 0)
{
Buffer.BlockCopy(rgb, cbSize - cbSize % BlockSizeBytes + ibStart, _processingBuffer, 0, cbSize % BlockSizeBytes);
_processingBufferCount = cbSize % BlockSizeBytes;
}
}
protected override byte[] HashFinal()
{
var hash = new byte[16];
int i, j;
ProcessFinalBlock(_processingBuffer, 0, _processingBufferCount);
for (i = 0; i < 4; i++)
{
for (j = 0; j < 4; j++)
hash[i * 4 + j] = (byte)(_h[i] >> j * 8);
}
return hash;
}
internal void AddLength(ulong length, byte[] buffer, int position)
{
buffer[position++] = (byte)length;
buffer[position++] = (byte)(length >> 8);
buffer[position++] = (byte)(length >> 16);
buffer[position++] = (byte)(length >> 24);
buffer[position++] = (byte)(length >> 32);
buffer[position++] = (byte)(length >> 40);
buffer[position++] = (byte)(length >> 48);
buffer[position] = (byte)(length >> 56);
}
void ProcessBlock(byte[] inputBuffer, int inputOffset)
{
uint a, b, c, d;
int i;
_count += BlockSizeBytes;
for (i = 0; i < 16; i++)
{
_buff[i] = inputBuffer[inputOffset + 4 * i] | ((uint)inputBuffer[inputOffset + 4 * i + 1] << 8) | ((uint)inputBuffer[inputOffset + 4 * i + 2] << 16) |
((uint)inputBuffer[inputOffset + 4 * i + 3] << 24);
}
a = _h[0];
b = _h[1];
c = _h[2];
d = _h[3];
// This function was unrolled because it seems to be doubling our performance with current compiler/VM.
// Possibly roll up if this changes.
// ---- Round 1 --------
a += (((c ^ d) & b) ^ d) + K[0] + _buff[0];
a = (a << 7) | (a >> 25);
a += b;
d += (((b ^ c) & a) ^ c) + K[1] + _buff[1];
d = (d << 12) | (d >> 20);
d += a;
c += (((a ^ b) & d) ^ b) + K[2] + _buff[2];
c = (c << 17) | (c >> 15);
c += d;
b += (((d ^ a) & c) ^ a) + K[3] + _buff[3];
b = (b << 22) | (b >> 10);
b += c;
a += (((c ^ d) & b) ^ d) + K[4] + _buff[4];
a = (a << 7) | (a >> 25);
a += b;
d += (((b ^ c) & a) ^ c) + K[5] + _buff[5];
d = (d << 12) | (d >> 20);
d += a;
c += (((a ^ b) & d) ^ b) + K[6] + _buff[6];
c = (c << 17) | (c >> 15);
c += d;
b += (((d ^ a) & c) ^ a) + K[7] + _buff[7];
b = (b << 22) | (b >> 10);
b += c;
a += (((c ^ d) & b) ^ d) + K[8] + _buff[8];
a = (a << 7) | (a >> 25);
a += b;
d += (((b ^ c) & a) ^ c) + K[9] + _buff[9];
d = (d << 12) | (d >> 20);
d += a;
c += (((a ^ b) & d) ^ b) + K[10] + _buff[10];
c = (c << 17) | (c >> 15);
c += d;
b += (((d ^ a) & c) ^ a) + K[11] + _buff[11];
b = (b << 22) | (b >> 10);
b += c;
a += (((c ^ d) & b) ^ d) + K[12] + _buff[12];
a = (a << 7) | (a >> 25);
a += b;
d += (((b ^ c) & a) ^ c) + K[13] + _buff[13];
d = (d << 12) | (d >> 20);
d += a;
c += (((a ^ b) & d) ^ b) + K[14] + _buff[14];
c = (c << 17) | (c >> 15);
c += d;
b += (((d ^ a) & c) ^ a) + K[15] + _buff[15];
b = (b << 22) | (b >> 10);
b += c;
// ---- Round 2 --------
a += (((b ^ c) & d) ^ c) + K[16] + _buff[1];
a = (a << 5) | (a >> 27);
a += b;
d += (((a ^ b) & c) ^ b) + K[17] + _buff[6];
d = (d << 9) | (d >> 23);
d += a;
c += (((d ^ a) & b) ^ a) + K[18] + _buff[11];
c = (c << 14) | (c >> 18);
c += d;
b += (((c ^ d) & a) ^ d) + K[19] + _buff[0];
b = (b << 20) | (b >> 12);
b += c;
a += (((b ^ c) & d) ^ c) + K[20] + _buff[5];
a = (a << 5) | (a >> 27);
a += b;
d += (((a ^ b) & c) ^ b) + K[21] + _buff[10];
d = (d << 9) | (d >> 23);
d += a;
c += (((d ^ a) & b) ^ a) + K[22] + _buff[15];
c = (c << 14) | (c >> 18);
c += d;
b += (((c ^ d) & a) ^ d) + K[23] + _buff[4];
b = (b << 20) | (b >> 12);
b += c;
a += (((b ^ c) & d) ^ c) + K[24] + _buff[9];
a = (a << 5) | (a >> 27);
a += b;
d += (((a ^ b) & c) ^ b) + K[25] + _buff[14];
d = (d << 9) | (d >> 23);
d += a;
c += (((d ^ a) & b) ^ a) + K[26] + _buff[3];
c = (c << 14) | (c >> 18);
c += d;
b += (((c ^ d) & a) ^ d) + K[27] + _buff[8];
b = (b << 20) | (b >> 12);
b += c;
a += (((b ^ c) & d) ^ c) + K[28] + _buff[13];
a = (a << 5) | (a >> 27);
a += b;
d += (((a ^ b) & c) ^ b) + K[29] + _buff[2];
d = (d << 9) | (d >> 23);
d += a;
c += (((d ^ a) & b) ^ a) + K[30] + _buff[7];
c = (c << 14) | (c >> 18);
c += d;
b += (((c ^ d) & a) ^ d) + K[31] + _buff[12];
b = (b << 20) | (b >> 12);
b += c;
// ---- Round 3 --------
a += (b ^ c ^ d) + K[32] + _buff[5];
a = (a << 4) | (a >> 28);
a += b;
d += (a ^ b ^ c) + K[33] + _buff[8];
d = (d << 11) | (d >> 21);
d += a;
c += (d ^ a ^ b) + K[34] + _buff[11];
c = (c << 16) | (c >> 16);
c += d;
b += (c ^ d ^ a) + K[35] + _buff[14];
b = (b << 23) | (b >> 9);
b += c;
a += (b ^ c ^ d) + K[36] + _buff[1];
a = (a << 4) | (a >> 28);
a += b;
d += (a ^ b ^ c) + K[37] + _buff[4];
d = (d << 11) | (d >> 21);
d += a;
c += (d ^ a ^ b) + K[38] + _buff[7];
c = (c << 16) | (c >> 16);
c += d;
b += (c ^ d ^ a) + K[39] + _buff[10];
b = (b << 23) | (b >> 9);
b += c;
a += (b ^ c ^ d) + K[40] + _buff[13];
a = (a << 4) | (a >> 28);
a += b;
d += (a ^ b ^ c) + K[41] + _buff[0];
d = (d << 11) | (d >> 21);
d += a;
c += (d ^ a ^ b) + K[42] + _buff[3];
c = (c << 16) | (c >> 16);
c += d;
b += (c ^ d ^ a) + K[43] + _buff[6];
b = (b << 23) | (b >> 9);
b += c;
a += (b ^ c ^ d) + K[44] + _buff[9];
a = (a << 4) | (a >> 28);
a += b;
d += (a ^ b ^ c) + K[45] + _buff[12];
d = (d << 11) | (d >> 21);
d += a;
c += (d ^ a ^ b) + K[46] + _buff[15];
c = (c << 16) | (c >> 16);
c += d;
b += (c ^ d ^ a) + K[47] + _buff[2];
b = (b << 23) | (b >> 9);
b += c;
// ---- Round 4 --------
a += ((~d | b) ^ c) + K[48] + _buff[0];
a = (a << 6) | (a >> 26);
a += b;
d += ((~c | a) ^ b) + K[49] + _buff[7];
d = (d << 10) | (d >> 22);
d += a;
c += ((~b | d) ^ a) + K[50] + _buff[14];
c = (c << 15) | (c >> 17);
c += d;
b += ((~a | c) ^ d) + K[51] + _buff[5];
b = (b << 21) | (b >> 11);
b += c;
a += ((~d | b) ^ c) + K[52] + _buff[12];
a = (a << 6) | (a >> 26);
a += b;
d += ((~c | a) ^ b) + K[53] + _buff[3];
d = (d << 10) | (d >> 22);
d += a;
c += ((~b | d) ^ a) + K[54] + _buff[10];
c = (c << 15) | (c >> 17);
c += d;
b += ((~a | c) ^ d) + K[55] + _buff[1];
b = (b << 21) | (b >> 11);
b += c;
a += ((~d | b) ^ c) + K[56] + _buff[8];
a = (a << 6) | (a >> 26);
a += b;
d += ((~c | a) ^ b) + K[57] + _buff[15];
d = (d << 10) | (d >> 22);
d += a;
c += ((~b | d) ^ a) + K[58] + _buff[6];
c = (c << 15) | (c >> 17);
c += d;
b += ((~a | c) ^ d) + K[59] + _buff[13];
b = (b << 21) | (b >> 11);
b += c;
a += ((~d | b) ^ c) + K[60] + _buff[4];
a = (a << 6) | (a >> 26);
a += b;
d += ((~c | a) ^ b) + K[61] + _buff[11];
d = (d << 10) | (d >> 22);
d += a;
c += ((~b | d) ^ a) + K[62] + _buff[2];
c = (c << 15) | (c >> 17);
c += d;
b += ((~a | c) ^ d) + K[63] + _buff[9];
b = (b << 21) | (b >> 11);
b += c;
_h[0] += a;
_h[1] += b;
_h[2] += c;
_h[3] += d;
}
void ProcessFinalBlock(byte[] inputBuffer, int inputOffset, int inputCount)
{
ulong total = _count + (ulong)inputCount;
var paddingSize = (int)(56 - total % BlockSizeBytes);
if (paddingSize < 1)
paddingSize += BlockSizeBytes;
var fooBuffer = new byte[inputCount + paddingSize + 8];
for (var i = 0; i < inputCount; i++)
fooBuffer[i] = inputBuffer[i + inputOffset];
fooBuffer[inputCount] = 0x80;
for (int i = inputCount + 1; i < inputCount + paddingSize; i++)
fooBuffer[i] = 0x00;
// I deal in bytes. The algorithm deals in bits.
ulong size = total << 3;
AddLength(size, fooBuffer, inputCount + paddingSize);
ProcessBlock(fooBuffer, 0);
if (inputCount + paddingSize + 8 == 128)
ProcessBlock(fooBuffer, 64);
}
~MD5CryptoServiceProvider()
{
Dispose(false);
}
}
}