ASCU_ALL/PrintPDF/PdfSharp/Pdf.Security/MD5Managed.cs
2021-05-25 17:00:45 +05:00

426 lines
17 KiB
C#

#region PDFsharp - A .NET library for processing PDF
//
// Authors:
// Stefan Lange
//
// Copyright (c) 2005-2017 empira Software GmbH, Cologne Area (Germany)
//
// http://www.pdfsharp.com
// http://sourceforge.net/projects/pdfsharp
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
#endregion
// Based on code from here:
// http://archive.msdn.microsoft.com/SilverlightMD5/Release/ProjectReleases.aspx?ReleaseId=2206
//
// **************************************************************
// * Raw implementation of the MD5 hash algorithm
// * from RFC 1321.
// *
// * Written By: Reid Borsuk and Jenny Zheng
// * Copyright (c) Microsoft Corporation. All rights reserved.
// **************************************************************
using System;
using System.Diagnostics;
#if !NETFX_CORE && !UWP
using System.Security.Cryptography;
#endif
// ReSharper disable InconsistentNaming
#if SILVERLIGHT || WINDOWS_PHONE || UWP || (GDI && DEBUG)
namespace PdfSharp.Pdf.Security
{
#if UWP
class HashAlgorithm
{
public int HashSizeValue { get; set; }
public virtual void Initialize()
{ }
protected virtual void HashCore(byte[] array, int ibStart, int cbSize)
{ }
protected virtual byte[] HashFinal()
{
return null;
}
public byte[] HashValue { get; set; }
public void TransformBlock(byte[] a, int b, int c, byte[] d, int e)
{ }
public void TransformFinalBlock(byte[] a, int b, int c)
{ }
public byte[] ComputeHash(byte[] a)
{
return null;
}
public byte[] Hash
{
get { return null; }
}
}
#endif
/// <summary>
/// A managed implementation of the MD5 algorithm.
/// Necessary because MD5 is not part of the framework in Silverlight and WP.
/// </summary>
class MD5Managed
//#if !UWP
: HashAlgorithm // TODO: WinRT has not even a HashAlgorithm base class.
//#endif
{
// Intitial values as defined in RFC 1321.
const uint A = 0x67452301;
const uint B = 0xefcdab89;
const uint C = 0x98badcfe;
const uint D = 0x10325476;
public MD5Managed()
{
HashSizeValue = 128;
Initialize();
}
public sealed override void Initialize()
{
_data = new byte[64];
_dataSize = 0;
_totalLength = 0;
_abcd = new MD5Core.ABCDStruct();
// Intitial values as defined in RFC 1321.
_abcd.A = A;
_abcd.B = B;
_abcd.C = C;
_abcd.D = D;
}
protected override void HashCore(byte[] array, int ibStart, int cbSize)
{
int startIndex = ibStart;
int totalArrayLength = _dataSize + cbSize;
if (totalArrayLength >= 64)
{
Array.Copy(array, startIndex, _data, _dataSize, 64 - _dataSize);
// Process message of 64 bytes (512 bits)
MD5Core.GetHashBlock(_data, ref _abcd, 0);
startIndex += 64 - _dataSize;
totalArrayLength -= 64;
while (totalArrayLength >= 64)
{
Array.Copy(array, startIndex, _data, 0, 64);
MD5Core.GetHashBlock(array, ref _abcd, startIndex);
totalArrayLength -= 64;
startIndex += 64;
}
_dataSize = totalArrayLength;
Array.Copy(array, startIndex, _data, 0, totalArrayLength);
}
else
{
Array.Copy(array, startIndex, _data, _dataSize, cbSize);
_dataSize = totalArrayLength;
}
_totalLength += cbSize;
}
protected override byte[] HashFinal()
{
HashValue = MD5Core.GetHashFinalBlock(_data, 0, _dataSize, _abcd, _totalLength * 8);
return HashValue;
}
byte[] _data;
MD5Core.ABCDStruct _abcd;
Int64 _totalLength;
int _dataSize;
static class MD5Core
{
#if true
public static byte[] GetHash(byte[] input)
{
if (null == input)
throw new ArgumentNullException("input");
// Intitial values defined in RFC 1321.
ABCDStruct abcd = new ABCDStruct();
abcd.A = A;
abcd.B = B;
abcd.C = C;
abcd.D = D;
// We pass in the input array by block, the final block of data must be handled specially for padding & length embeding.
int startIndex = 0;
while (startIndex <= input.Length - 64)
{
GetHashBlock(input, ref abcd, startIndex);
startIndex += 64;
}
// The final data block.
return GetHashFinalBlock(input, startIndex, input.Length - startIndex, abcd, (Int64)input.Length * 8);
}
#endif
internal static byte[] GetHashFinalBlock(byte[] input, int ibStart, int cbSize, ABCDStruct abcd, Int64 len)
{
byte[] working = new byte[64];
byte[] length = BitConverter.GetBytes(len);
// Padding is a single bit 1, followed by the number of 0s required to make size congruent to 448 modulo 512. Step 1 of RFC 1321
// The CLR ensures that our buffer is 0-assigned, we don't need to explicitly set it. This is why it ends up being quicker to just
// use a temporary array rather then doing in-place assignment (5% for small inputs)
Array.Copy(input, ibStart, working, 0, cbSize);
working[cbSize] = 0x80;
// We have enough room to store the length in this chunk.
if (cbSize <= 56)
{
Array.Copy(length, 0, working, 56, 8);
GetHashBlock(working, ref abcd, 0);
}
else // We need an aditional chunk to store the length.
{
GetHashBlock(working, ref abcd, 0);
// Create an entirely new chunk due to the 0-assigned trick mentioned above, to avoid an extra function call clearing the array.
working = new byte[64];
Array.Copy(length, 0, working, 56, 8);
GetHashBlock(working, ref abcd, 0);
}
byte[] output = new byte[16];
Array.Copy(BitConverter.GetBytes(abcd.A), 0, output, 0, 4);
Array.Copy(BitConverter.GetBytes(abcd.B), 0, output, 4, 4);
Array.Copy(BitConverter.GetBytes(abcd.C), 0, output, 8, 4);
Array.Copy(BitConverter.GetBytes(abcd.D), 0, output, 12, 4);
return output;
}
internal static void GetHashBlock(byte[] input, ref ABCDStruct ABCDValue, int ibStart)
{
uint[] temp = Converter(input, ibStart);
uint a = ABCDValue.A;
uint b = ABCDValue.B;
uint c = ABCDValue.C;
uint d = ABCDValue.D;
a = r1(a, b, c, d, temp[0], 7, 0xd76aa478);
d = r1(d, a, b, c, temp[1], 12, 0xe8c7b756);
c = r1(c, d, a, b, temp[2], 17, 0x242070db);
b = r1(b, c, d, a, temp[3], 22, 0xc1bdceee);
a = r1(a, b, c, d, temp[4], 7, 0xf57c0faf);
d = r1(d, a, b, c, temp[5], 12, 0x4787c62a);
c = r1(c, d, a, b, temp[6], 17, 0xa8304613);
b = r1(b, c, d, a, temp[7], 22, 0xfd469501);
a = r1(a, b, c, d, temp[8], 7, 0x698098d8);
d = r1(d, a, b, c, temp[9], 12, 0x8b44f7af);
c = r1(c, d, a, b, temp[10], 17, 0xffff5bb1);
b = r1(b, c, d, a, temp[11], 22, 0x895cd7be);
a = r1(a, b, c, d, temp[12], 7, 0x6b901122);
d = r1(d, a, b, c, temp[13], 12, 0xfd987193);
c = r1(c, d, a, b, temp[14], 17, 0xa679438e);
b = r1(b, c, d, a, temp[15], 22, 0x49b40821);
a = r2(a, b, c, d, temp[1], 5, 0xf61e2562);
d = r2(d, a, b, c, temp[6], 9, 0xc040b340);
c = r2(c, d, a, b, temp[11], 14, 0x265e5a51);
b = r2(b, c, d, a, temp[0], 20, 0xe9b6c7aa);
a = r2(a, b, c, d, temp[5], 5, 0xd62f105d);
d = r2(d, a, b, c, temp[10], 9, 0x02441453);
c = r2(c, d, a, b, temp[15], 14, 0xd8a1e681);
b = r2(b, c, d, a, temp[4], 20, 0xe7d3fbc8);
a = r2(a, b, c, d, temp[9], 5, 0x21e1cde6);
d = r2(d, a, b, c, temp[14], 9, 0xc33707d6);
c = r2(c, d, a, b, temp[3], 14, 0xf4d50d87);
b = r2(b, c, d, a, temp[8], 20, 0x455a14ed);
a = r2(a, b, c, d, temp[13], 5, 0xa9e3e905);
d = r2(d, a, b, c, temp[2], 9, 0xfcefa3f8);
c = r2(c, d, a, b, temp[7], 14, 0x676f02d9);
b = r2(b, c, d, a, temp[12], 20, 0x8d2a4c8a);
a = r3(a, b, c, d, temp[5], 4, 0xfffa3942);
d = r3(d, a, b, c, temp[8], 11, 0x8771f681);
c = r3(c, d, a, b, temp[11], 16, 0x6d9d6122);
b = r3(b, c, d, a, temp[14], 23, 0xfde5380c);
a = r3(a, b, c, d, temp[1], 4, 0xa4beea44);
d = r3(d, a, b, c, temp[4], 11, 0x4bdecfa9);
c = r3(c, d, a, b, temp[7], 16, 0xf6bb4b60);
b = r3(b, c, d, a, temp[10], 23, 0xbebfbc70);
a = r3(a, b, c, d, temp[13], 4, 0x289b7ec6);
d = r3(d, a, b, c, temp[0], 11, 0xeaa127fa);
c = r3(c, d, a, b, temp[3], 16, 0xd4ef3085);
b = r3(b, c, d, a, temp[6], 23, 0x04881d05);
a = r3(a, b, c, d, temp[9], 4, 0xd9d4d039);
d = r3(d, a, b, c, temp[12], 11, 0xe6db99e5);
c = r3(c, d, a, b, temp[15], 16, 0x1fa27cf8);
b = r3(b, c, d, a, temp[2], 23, 0xc4ac5665);
a = r4(a, b, c, d, temp[0], 6, 0xf4292244);
d = r4(d, a, b, c, temp[7], 10, 0x432aff97);
c = r4(c, d, a, b, temp[14], 15, 0xab9423a7);
b = r4(b, c, d, a, temp[5], 21, 0xfc93a039);
a = r4(a, b, c, d, temp[12], 6, 0x655b59c3);
d = r4(d, a, b, c, temp[3], 10, 0x8f0ccc92);
c = r4(c, d, a, b, temp[10], 15, 0xffeff47d);
b = r4(b, c, d, a, temp[1], 21, 0x85845dd1);
a = r4(a, b, c, d, temp[8], 6, 0x6fa87e4f);
d = r4(d, a, b, c, temp[15], 10, 0xfe2ce6e0);
c = r4(c, d, a, b, temp[6], 15, 0xa3014314);
b = r4(b, c, d, a, temp[13], 21, 0x4e0811a1);
a = r4(a, b, c, d, temp[4], 6, 0xf7537e82);
d = r4(d, a, b, c, temp[11], 10, 0xbd3af235);
c = r4(c, d, a, b, temp[2], 15, 0x2ad7d2bb);
b = r4(b, c, d, a, temp[9], 21, 0xeb86d391);
ABCDValue.A = unchecked(a + ABCDValue.A);
ABCDValue.B = unchecked(b + ABCDValue.B);
ABCDValue.C = unchecked(c + ABCDValue.C);
ABCDValue.D = unchecked(d + ABCDValue.D);
}
// Manually unrolling these equations nets us a 20% performance improvement
private static uint r1(uint a, uint b, uint c, uint d, uint x, int s, uint t)
{
// (b + LSR((a + F(b, c, d) + x + t), s))
// F(x, y, z) ((x & y) | ((x ^ 0xFFFFFFFF) & z))
return unchecked(b + LSR((a + ((b & c) | ((b ^ 0xFFFFFFFF) & d)) + x + t), s));
}
private static uint r2(uint a, uint b, uint c, uint d, uint x, int s, uint t)
{
// (b + LSR((a + G(b, c, d) + x + t), s))
// G(x, y, z) ((x & z) | (y & (z ^ 0xFFFFFFFF)))
return unchecked(b + LSR((a + ((b & d) | (c & (d ^ 0xFFFFFFFF))) + x + t), s));
}
private static uint r3(uint a, uint b, uint c, uint d, uint x, int s, uint t)
{
// (b + LSR((a + H(b, c, d) + k + i), s))
// H(x, y, z) (x ^ y ^ z)
return unchecked(b + LSR((a + (b ^ c ^ d) + x + t), s));
}
private static uint r4(uint a, uint b, uint c, uint d, uint x, int s, uint t)
{
// (b + LSR((a + I(b, c, d) + k + i), s))
// I(x, y, z) (y ^ (x | (z ^ 0xFFFFFFFF)))
return unchecked(b + LSR((a + (c ^ (b | (d ^ 0xFFFFFFFF))) + x + t), s));
}
// Implementation of left rotate
// s is an int instead of a uint becuase the CLR requires the argument passed to >>/<< is of
// type int. Doing the demoting inside this function would add overhead.
private static uint LSR(uint i, int s)
{
return (i << s) | (i >> (32 - s));
}
// Convert input array into array of UInts.
static uint[] Converter(byte[] input, int ibStart)
{
if (null == input)
throw new ArgumentNullException("input");
uint[] result = new uint[16];
for (int idx = 0; idx < 16; idx++)
{
result[idx] = (uint)input[ibStart + idx * 4];
result[idx] += (uint)input[ibStart + idx * 4 + 1] << 8;
result[idx] += (uint)input[ibStart + idx * 4 + 2] << 16;
result[idx] += (uint)input[ibStart + idx * 4 + 3] << 24;
Debug.Assert(result[idx] ==
(input[ibStart + idx * 4]) +
((uint)input[ibStart + idx * 4 + 1] << 8) +
((uint)input[ibStart + idx * 4 + 2] << 16) +
((uint)input[ibStart + idx * 4 + 3] << 24));
}
return result;
}
// Simple struct for the (a,b,c,d) which is used to compute the mesage digest.
public struct ABCDStruct
{
public uint A;
public uint B;
public uint C;
public uint D;
}
}
}
#if GDI && DEBUG && true_
// See here for details: http://archive.msdn.microsoft.com/SilverlightMD5/WorkItem/View.aspx?WorkItemId=3
public static class TestMD5
{
public static void Test()
{
Random rnd = new Random();
for (int i = 0; i < 10000; i++)
{
int count = rnd.Next(1000) + 1;
Console.WriteLine(String.Format("{0}: {1}", i, count));
Test2(count);
}
}
static void Test2(int count)
{
byte[] bytes = new byte[count];
for (int idx = 0; idx < count; idx += 16)
Array.Copy(Guid.NewGuid().ToByteArray(), 0, bytes, idx, Math.Min(16, count - idx));
MD5 md5dotNet = new MD5CryptoServiceProvider();
md5dotNet.Initialize();
MD5Managed md5m = new MD5Managed();
md5m.Initialize();
byte[] result1 = md5dotNet.ComputeHash(bytes);
byte[] result2 = md5m.ComputeHash(bytes);
if (!CompareBytes(result1, result2))
{
count.GetType();
//throw new Exception("Bug in MD5Managed...");
}
}
static bool CompareBytes(byte[] bytes1, byte[] bytes2)
{
for (int idx = 0; idx < bytes1.Length; idx++)
{
if (bytes1[idx] != bytes2[idx])
return false;
}
return true;
}
}
#endif
}
#endif