#region
/* -----------------------------------------------------------------------
*
*
* Copyright 2011-2012 GRNET S.A. All rights reserved.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. 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.
*
*
* THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``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 GRNET S.A 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.
*
* The views and conclusions contained in the software and
* documentation are those of the authors and should not be
* interpreted as representing official policies, either expressed
* or implied, of GRNET S.A.
*
* -----------------------------------------------------------------------
*/
#endregion
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Diagnostics.Contracts;
using System.IO;
using System.Reflection;
using System.Runtime.Remoting.Metadata.W3cXsd2001;
using System.Security.Cryptography;
using System.Threading.Tasks;
using System.Linq;
namespace Pithos.Network
{
public static class Signature
{
private static readonly log4net.ILog Log = log4net.LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
public static string CalculateMD5(FileInfo info)
{
if (info==null)
throw new ArgumentNullException("info");
if (String.IsNullOrWhiteSpace(info.FullName))
throw new ArgumentException("info.FullName is empty","info");
Contract.EndContractBlock();
return CalculateMD5(info.FullName);
}
public static string CalculateMD5(string path)
{
if (String.IsNullOrWhiteSpace(path))
throw new ArgumentNullException("path");
Contract.EndContractBlock();
//DON'T calculate hashes for folders
if (Directory.Exists(path))
return "";
string hash;
using (var hasher = MD5.Create())
using (var stream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read, 65536, true))
{
var hashBytes = hasher.ComputeHash(stream);
hash = hashBytes.ToHashString();
}
return hash;
}
/*
public static string BytesToString(byte[] hashBytes)
{
var shb=new SoapHexBinary(hashBytes);
return shb.ToString();
}
public static byte[] StringToBytes(string hash)
{
var shb=SoapHexBinary.Parse(hash);
return shb.Value;
}
*/
public static byte[] ToBytes(this string hash)
{
var shb = SoapHexBinary.Parse(hash);
return shb.Value;
}
public static string ToHashString(this byte[] hashBytes)
{
var shb = new SoapHexBinary(hashBytes);
return shb.ToString().ToLower();
}
public static TreeHash CalculateTreeHash(FileSystemInfo fileInfo, int blockSize, string algorithm)
{
if (fileInfo == null)
throw new ArgumentNullException("fileInfo");
if (String.IsNullOrWhiteSpace(fileInfo.FullName))
throw new ArgumentException("fileInfo.FullName is empty", "fileInfo");
if (blockSize <= 0)
throw new ArgumentOutOfRangeException("blockSize", "blockSize must be a value greater than zero ");
if (String.IsNullOrWhiteSpace(algorithm))
throw new ArgumentNullException("algorithm");
Contract.EndContractBlock();
if (fileInfo is DirectoryInfo || !fileInfo.Exists)
return TreeHash.Empty;
return CalculateTreeHash(fileInfo.FullName, blockSize, algorithm);
}
///
/// Calculates a file's tree hash synchronously, using the specified block size
///
/// Path to an existing file
/// Block size used to calculate leaf hashes
///
/// A with the block hashes and top hash
public static TreeHash CalculateTreeHash(string filePath, int blockSize, string algorithm)
{
if (String.IsNullOrWhiteSpace(filePath))
throw new ArgumentNullException("filePath");
if (blockSize<=0)
throw new ArgumentOutOfRangeException("blockSize","blockSize must be a value greater than zero ");
if (String.IsNullOrWhiteSpace(algorithm))
throw new ArgumentNullException("algorithm");
Contract.EndContractBlock();
var hash=CalculateTreeHashAsync(filePath, blockSize, algorithm, 2);
return hash.Result;
}
public static async Task CalculateTreeHashAsync(FileInfo fileInfo, int blockSize, string algorithm, byte parallelism)
{
if (fileInfo == null)
throw new ArgumentNullException("fileInfo");
if (String.IsNullOrWhiteSpace(fileInfo.FullName))
throw new ArgumentNullException("fileInfo.FullName is empty","fileInfo");
if (blockSize <= 0)
throw new ArgumentOutOfRangeException("blockSize", "blockSize must be a value greater than zero ");
if (String.IsNullOrWhiteSpace(algorithm))
throw new ArgumentNullException("algorithm");
Contract.EndContractBlock();
return await CalculateTreeHashAsync(fileInfo.FullName, blockSize, algorithm, parallelism);
}
public static async Task CalculateTreeHashAsync(string filePath, int blockSize,string algorithm, int parallelism)
{
if (String.IsNullOrWhiteSpace(filePath))
throw new ArgumentNullException("filePath");
if (blockSize <= 0)
throw new ArgumentOutOfRangeException("blockSize", "blockSize must be a value greater than zero ");
if (String.IsNullOrWhiteSpace(algorithm))
throw new ArgumentNullException("algorithm");
Contract.EndContractBlock();
if (Log.IsDebugEnabled)
Log.DebugFormat("Calc Signature [{0}]",filePath);
//DON'T calculate hashes for folders
if (Directory.Exists(filePath))
return new TreeHash(algorithm);
//The hash of a non-existent file is the empty hash
if (!File.Exists(filePath))
return new TreeHash(algorithm);
//Calculate the hash of all blocks using a blockhash iterator
using (var stream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite, blockSize, true))
{
//Calculate the blocks asyncrhonously
var hashes = await BlockHashAlgorithms.CalculateBlockHashesInPlacePFor(stream, blockSize, algorithm, parallelism);
//And then proceed with creating and returning a TreeHash
var length = stream.Length;
var list = hashes.OrderBy(pair => pair.Key).Select(pair => pair.Value).ToList();
var treeHash = new TreeHash(algorithm)
{
Bytes = length,
BlockSize = blockSize,
Hashes = list
};
return treeHash;
}
}
public static byte[] CalculateTopHash(IList hashMap, string algorithm)
{
if (hashMap == null)
throw new ArgumentNullException("hashMap");
if (String.IsNullOrWhiteSpace(algorithm))
throw new ArgumentNullException("algorithm");
Contract.EndContractBlock();
var hashCount = hashMap.Count;
//The tophash of an empty hashmap is an empty array
if (hashCount == 0)
return new byte[0];
//The tophash of a one-item hashmap is the hash itself
if (hashCount == 1)
return hashMap[0];
//Calculate the required number of leaf nodes
var leafs =(int)Math.Pow(2, Math.Ceiling(Math.Log(hashCount,2)));
//The size of all nodes is the same and equal to the size of the input hashes
var hashSize = hashMap[0].Length;
//If the hashmap containes fewer nodes than the required leaf count, we need to fill
//the rest with empty blocks
byte[] empty=null;
if (hashCount < leafs)
empty = new byte[hashSize];
//New hashes will be stored in a dictionary keyed by their step to preserve order
var newHashes=new ConcurrentDictionary();
Parallel.For(0, leafs/2,
(step, state) =>
{
using (var hasher = HashAlgorithm.Create(algorithm))
{
var i = step*2;
var block1 = i <= hashCount - 1 ? hashMap[i] : empty;
var block2 = i <= hashCount - 2 ? hashMap[i + 1] : empty;
hasher.TransformBlock(block1, 0, block1.Length, null, 0);
hasher.TransformFinalBlock(block2, 0, block2.Length);
var finalHash = hasher.Hash;
//Store the final value in its proper place
newHashes[step] = finalHash;
}
});
//Extract the hashes to a list ordered by their step
var hashes = newHashes.OrderBy(pair => pair.Key).Select(pair => pair.Value).ToList();
return CalculateTopHash(hashes, algorithm);
}
public static byte[] CalculateHash(byte[] buffer,string algorithm)
{
if (buffer == null)
throw new ArgumentNullException("buffer");
if (String.IsNullOrWhiteSpace(algorithm))
throw new ArgumentNullException("algorithm");
Contract.EndContractBlock();
using (var hasher = HashAlgorithm.Create(algorithm))
{
var hash = hasher.ComputeHash(buffer, 0, buffer.Length);
return hash;
}
}
}
}