aaru-dps/Aaru.Checksums
1
0
Fork 0
mirror of https://github.com/aaru-dps/Aaru.Checksums.git synced 2025-12-16 19:24:29 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add native checksums.

Browse Source
This commit is contained in:
Natalia Portillo
2021-10-14 01:38:59 +01:00
parent c398a3ef39
commit 3145e0a2f9
8 changed files with 858 additions and 78 deletions
Download Patch File Download Diff File Expand all files Collapse all files

113
CRC32Context.cs
View File

@@ -32,6 +32,7 @@
using System;
using System.IO;
using System.Runtime.InteropServices;
using System.Runtime.Intrinsics.Arm;
using System.Runtime.Intrinsics.X86;
using System.Text;
@@ -333,8 +334,10 @@ namespace Aaru.Checksums
};
readonly uint _finalSeed;
readonly IntPtr _nativeContext;
readonly uint[][] _table;
readonly bool _useIso;
readonly bool _useNative;
uint _hashInt;
/// <summary>Initializes the CRC32 table and seed as CRC32-ISO</summary>
@@ -344,6 +347,12 @@ namespace Aaru.Checksums
_finalSeed = CRC32_ISO_SEED;
_table = _isoCrc32Table;
_useIso = true;
if(!Native.IsSupported)
return;
_nativeContext = crc32_init();
_useNative = _nativeContext != IntPtr.Zero;
}
/// <summary>Initializes the CRC32 table with a custom polynomial and seed</summary>
@@ -353,14 +362,21 @@ namespace Aaru.Checksums
_finalSeed = seed;
_useIso = polynomial == CRC32_ISO_POLY && seed == CRC32_ISO_SEED;
_table = GenerateTable(polynomial);
if(Native.IsSupported && _useIso)
{
_nativeContext = crc32_init();
_useNative = _nativeContext != IntPtr.Zero;
}
else
_table = GenerateTable(polynomial);
}
/// <inheritdoc />
/// <summary>Updates the hash with data.</summary>
/// <param name="data">Data buffer.</param>
/// <param name="len">Length of buffer to hash.</param>
public void Update(byte[] data, uint len) => Step(ref _hashInt, _table, data, len, _useIso);
public void Update(byte[] data, uint len) =>
Step(ref _hashInt, _table, data, len, _useIso, _useNative, _nativeContext);
/// <inheritdoc />
/// <summary>Updates the hash with data.</summary>
@@ -369,20 +385,52 @@ namespace Aaru.Checksums
/// <inheritdoc />
/// <summary>Returns a byte array of the hash value.</summary>
public byte[] Final() => BigEndianBitConverter.GetBytes(_hashInt ^ _finalSeed);
public byte[] Final()
{
uint crc = _hashInt ^ _finalSeed;
if(!_useNative ||
!_useIso)
return BigEndianBitConverter.GetBytes(crc);
crc32_final(_nativeContext, ref crc);
crc32_free(_nativeContext);
return BigEndianBitConverter.GetBytes(crc);
}
/// <inheritdoc />
/// <summary>Returns a hexadecimal representation of the hash value.</summary>
public string End()
{
uint crc = _hashInt ^ _finalSeed;
var crc32Output = new StringBuilder();
for(int i = 0; i < BigEndianBitConverter.GetBytes(_hashInt ^ _finalSeed).Length; i++)
crc32Output.Append(BigEndianBitConverter.GetBytes(_hashInt ^ _finalSeed)[i].ToString("x2"));
if(_useNative && _useIso)
{
crc32_final(_nativeContext, ref crc);
crc32_free(_nativeContext);
}
for(int i = 0; i < BigEndianBitConverter.GetBytes(crc).Length; i++)
crc32Output.Append(BigEndianBitConverter.GetBytes(crc)[i].ToString("x2"));
return crc32Output.ToString();
}
[DllImport("libAaru.Checksums.Native", SetLastError = true)]
static extern IntPtr crc32_init();
[DllImport("libAaru.Checksums.Native", SetLastError = true)]
static extern int crc32_update(IntPtr ctx, byte[] data, uint len);
[DllImport("libAaru.Checksums.Native", SetLastError = true)]
static extern int crc32_final(IntPtr ctx, ref uint crc);
[DllImport("libAaru.Checksums.Native", SetLastError = true)]
static extern void crc32_free(IntPtr ctx);
static uint[][] GenerateTable(uint polynomial)
{
uint[][] table = new uint[8][];
@@ -410,8 +458,16 @@ namespace Aaru.Checksums
return table;
}
static void Step(ref uint previousCrc, uint[][] table, byte[] data, uint len, bool useIso)
static void Step(ref uint previousCrc, uint[][] table, byte[] data, uint len, bool useIso, bool useNative,
IntPtr nativeContext)
{
if(useNative && useIso)
{
crc32_update(nativeContext, data, len);
return;
}
int currentPos = 0;
if(useIso)
@@ -426,7 +482,7 @@ namespace Aaru.Checksums
if(blocks > 0)
{
previousCrc = ~Clmul.Step(data, blocks * 64, ~previousCrc);
previousCrc = ~CRC32.Clmul.Step(data, blocks * 64, ~previousCrc);
currentPos = (int)(blocks * 64);
len -= blocks * 64;
@@ -505,6 +561,16 @@ namespace Aaru.Checksums
/// <param name="seed">CRC seed</param>
public static string File(string filename, out byte[] hash, uint polynomial, uint seed)
{
bool useIso = polynomial == CRC32_ISO_POLY && seed == CRC32_ISO_SEED;
bool useNative = Native.IsSupported;
IntPtr nativeContext = IntPtr.Zero;
if(useNative && useIso)
{
nativeContext = crc32_init();
useNative = nativeContext != IntPtr.Zero;
}
var fileStream = new FileStream(filename, FileMode.Open);
uint localHashInt = seed;
@@ -516,14 +582,20 @@ namespace Aaru.Checksums
while(read > 0)
{
Step(ref localHashInt, localTable, buffer, (uint)read,
polynomial == CRC32_ISO_POLY && seed == CRC32_ISO_SEED);
Step(ref localHashInt, localTable, buffer, (uint)read, useIso, useNative, nativeContext);
read = fileStream.Read(buffer, 0, 65536);
}
localHashInt ^= seed;
hash = BigEndianBitConverter.GetBytes(localHashInt);
if(useNative && useIso)
{
crc32_final(nativeContext, ref localHashInt);
crc32_free(nativeContext);
}
hash = BigEndianBitConverter.GetBytes(localHashInt);
var crc32Output = new StringBuilder();
@@ -550,14 +622,31 @@ namespace Aaru.Checksums
/// <param name="seed">CRC seed</param>
public static string Data(byte[] data, uint len, out byte[] hash, uint polynomial, uint seed)
{
bool useIso = polynomial == CRC32_ISO_POLY && seed == CRC32_ISO_SEED;
bool useNative = Native.IsSupported;
IntPtr nativeContext = IntPtr.Zero;
if(useNative && useIso)
{
nativeContext = crc32_init();
useNative = nativeContext != IntPtr.Zero;
}
uint localHashInt = seed;
uint[][] localTable = GenerateTable(polynomial);
Step(ref localHashInt, localTable, data, len, polynomial == CRC32_ISO_POLY && seed == CRC32_ISO_SEED);
Step(ref localHashInt, localTable, data, len, useIso, useNative, nativeContext);
localHashInt ^= seed;
hash = BigEndianBitConverter.GetBytes(localHashInt);
if(useNative && useIso)
{
crc32_final(nativeContext, ref localHashInt);
crc32_free(nativeContext);
}
hash = BigEndianBitConverter.GetBytes(localHashInt);
var crc32Output = new StringBuilder();