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EDC15P_checksum.cs
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EDC15P_checksum.cs
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//---------------------------------------------------------------------------
//
// Bosch VAG TDI v4.1 - 2002 Checksum Algorithm Version 1.0
// Bosch VAG TDI v4.1 Checksum Algorithm Version 1.1
//
// Copyright 2007-2012 MTX Electronics
// Web: www.mtx-electronics.com
// Email: [email protected]
//
//---------------------------------------------------------------------------
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
namespace VAGSuite
{
public class EDC15P_checksum
{
public void DumpChecksumLocations(string info, byte[] allBytes)
{
//0x7BFFA & 0x7BFFB
byte b1 = allBytes[0x7BFFA];
byte b2 = allBytes[0x7BFFB];
int checksumAddress = 0;
bool found = true;
while (found)
{
found = false;
checksumAddress = Tools.Instance.findSequence(allBytes, checksumAddress, new byte[2] { b1, b2 }, new byte[2] { 1, 1 });
if (checksumAddress > 0)
{
if ((checksumAddress & 0x000F) == 0x000A)
{
int realAddress = checksumAddress + 2;
//Console.WriteLine(info + " detected checksumAddress: " + realAddress.ToString("X8"));
}
checksumAddress += 2;
found = true;
}
}
}
private UInt16 chk_match = 0;
public UInt16 ChecksumsMatch
{
get { return chk_match; }
set { chk_match = value; }
}
private UInt16 chk_found = 0;
public UInt16 ChecksumsFound
{
get { return chk_found; }
set { chk_found = value; }
}
private UInt16 chk_fixed = 0;
public UInt16 ChecksumsIncorrect
{
get { return chk_fixed; }
set { chk_fixed = value; }
}
private void DumpChecksum(string remark, byte[] allBytes, bool debugInfo)
{
if(debugInfo) Console.WriteLine(remark);//+ " " + allBytes[0x5BFFA].ToString("X2") + " " + allBytes[0x5BFFB].ToString("X2") + " " + allBytes[0x5BFFC].ToString("X2") + " " + allBytes[0x5BFFD].ToString("X2") + " " + allBytes[0x5BFFE].ToString("X2") + " " + allBytes[0x5BFFF].ToString("X2"));
}
// should consider empty banks as "were ok"
// should check for 54000 and 68000 as well?
// VW ARL file with different struct.
public ChecksumResult tdi41_checksum_search(byte[] file_buffer, UInt32 file_size, bool debug)
{
bool first_pass = true;
UInt32 chk_oldvalue, chk_value, chk_start_addr, chk_end_addr;
// 58000 was not there
UInt32[] chk_array = new UInt32[12] { 0x10000, 0x14000, 0x4C000, 0x50000, 0x50B80, 0x5C000, 0x60000, 0x60B80, 0x6C000, 0x70000, 0x70B80, 0x7C000 };
UInt16 seed_a = 0, seed_b = 0;
chk_found = 0;
chk_fixed = 0;
chk_match = 0;
for (; chk_found < chk_array.Length - 1; chk_found++)
{
chk_start_addr = chk_array[chk_found];
chk_end_addr = chk_array[chk_found + 1];
//DumpChecksum("chks " + chk_start_addr.ToString("X8") + "-" + chk_end_addr.ToString("X8"), file_buffer, debug);
if (!first_pass)
{
seed_a |= 0x8631;
seed_b |= 0xEFCD;
}
//if (CheckEmpty(file_buffer, chk_start_addr, chk_end_addr)) continue;
chk_oldvalue = ((UInt32)file_buffer[chk_end_addr - 1] << 24)
+ ((UInt32)file_buffer[chk_end_addr - 2] << 16)
+ ((UInt32)file_buffer[chk_end_addr - 3] << 8)
+ (UInt32)file_buffer[chk_end_addr - 4];
chk_value = tdi41_checksum_calculate(file_buffer, chk_start_addr, chk_end_addr - 4, seed_a, seed_b);
//Console.WriteLine("Checksum at address " + chk_end_addr.ToString("X8") + " - " + chk_end_addr.ToString("X8") + ", file: " + chk_oldvalue.ToString("X8") + " calculated: " + chk_value.ToString("X8"));
if (chk_oldvalue != chk_value && chk_oldvalue != 0xC3C3C3C3)
{
file_buffer[chk_end_addr - 4] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[chk_end_addr - 3] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[chk_end_addr - 2] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[chk_end_addr - 1] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
//Console.WriteLine("Checksum at address " + chk_end_addr.ToString("X8") + " failed, file: " + chk_oldvalue.ToString("X8") + " calculated: " + chk_value.ToString("X8"));
chk_fixed++;
}
if (chk_oldvalue == chk_value)
{
chk_match++;
}
first_pass = false;
}
Console.WriteLine("tdi41_chkfixed: " + chk_fixed.ToString() + " / " + chk_found.ToString());
Console.WriteLine("tdi41_chkmatch: " + chk_match.ToString() + " / " + chk_found.ToString());
//return ChecksumResult.ChecksumTypeError;
if (chk_fixed == 0) return ChecksumResult.ChecksumOK;
else if (chk_match > 3) return ChecksumResult.ChecksumFail;
else if (chk_fixed >= 6) return ChecksumResult.ChecksumTypeError;
return ChecksumResult.ChecksumFail;
}
public ChecksumResult tdi41v2_checksum_search(byte[] file_buffer, UInt32 file_size, bool debug)
{
bool first_pass = true;
UInt32 chk_oldvalue, chk_value, chk_start_addr, chk_end_addr;
//UInt32[] chk_array = new UInt32[8] { 0x10000, 0x14000, 0x4C000, 0x50000, 0x50B80, 0x58000, 0x58B80, 0x5C000, 0x60000, 0x64000, 0x68000, 0x70000, 0x70B80, 0x7C000 };
UInt32[] chk_array = new UInt32[8] { 0x10000, 0x14000, 0x58000, 0x58B80, 0x64000, 0x70000, 0x70B80, 0x7C000 };
UInt16 seed_a = 0, seed_b = 0;
chk_found = 0;
chk_fixed = 0;
chk_match = 0;
for (; chk_found < chk_array.Length - 1; chk_found++)
{
chk_start_addr = chk_array[chk_found];
chk_end_addr = chk_array[chk_found + 1];
// if array is empty, don't check
//DumpChecksum("chks " + chk_start_addr.ToString("X8") + "-" + chk_end_addr.ToString("X8"), file_buffer, debug);
if (!first_pass)
{
seed_a |= 0x8631;
seed_b |= 0xEFCD;
}
if (CheckEmpty(file_buffer, chk_start_addr, chk_end_addr)) continue;
chk_oldvalue = ((UInt32)file_buffer[chk_end_addr - 1] << 24)
+ ((UInt32)file_buffer[chk_end_addr - 2] << 16)
+ ((UInt32)file_buffer[chk_end_addr - 3] << 8)
+ (UInt32)file_buffer[chk_end_addr - 4];
chk_value = tdi41_checksum_calculate(file_buffer, chk_start_addr, chk_end_addr - 4, seed_a, seed_b);
if (chk_oldvalue != chk_value && chk_oldvalue != 0xC3C3C3C3)
{
file_buffer[chk_end_addr - 4] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[chk_end_addr - 3] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[chk_end_addr - 2] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[chk_end_addr - 1] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
//Console.WriteLine("Checksum at address " + chk_end_addr.ToString("X8") + " failed");
chk_fixed++;
}
else if (chk_value == chk_oldvalue)
{
chk_match++;
}
//Console.WriteLine("Checking " + chk_start_addr.ToString("X8") + " - " + chk_end_addr.ToString("X8") + " file " + chk_oldvalue.ToString("X8") + " calc " + chk_value.ToString("X8"));
first_pass = false;
}
Console.WriteLine("tdi41v2_chkfixed: " + chk_fixed.ToString() + " / " + chk_found.ToString());
Console.WriteLine("tdi41v2_chkmatch: " + chk_match.ToString() + " / " + chk_found.ToString());
if (chk_fixed == 0) return ChecksumResult.ChecksumOK;
else if (chk_match > 3) return ChecksumResult.ChecksumFail;
else if (chk_fixed >= 4) return ChecksumResult.ChecksumTypeError;
return ChecksumResult.ChecksumFail;
}
private bool CheckEmpty(byte[] file_buffer, uint chk_start_addr, uint chk_end_addr)
{
for (uint i = chk_start_addr; i < chk_end_addr - 4; i++)
{
if (file_buffer[i] != 0xC3) return false;
}
return true;
}
UInt32 tdi41_checksum_calculate(byte[] file_buffer, UInt32 chk_start_addr, UInt32 chk_end_addr, UInt16 seed_a, UInt16 seed_b)
{
UInt16 var_1;
byte var_2;
do
{
var_2 = 0;
seed_a ^= Convert.ToUInt16((((UInt16)file_buffer[chk_start_addr + 1] << 8) + (UInt16)file_buffer[chk_start_addr]));
chk_start_addr += 2;
if ((seed_b & 0xF) > 0)
{
var_1 = Convert.ToUInt16(seed_a >> (16 - (seed_b & 0xF)));
seed_a <<= (seed_b & 0xF);
seed_a |= var_1;
var_2 = Convert.ToByte(seed_a & 1);
}
seed_b -= Convert.ToUInt16((((UInt16)file_buffer[chk_start_addr + 1] << 8) + (UInt16)file_buffer[chk_start_addr]));
seed_b -= var_2;
chk_start_addr += 2;
seed_b ^= seed_a;
if (chk_start_addr == chk_end_addr)
break;
seed_a -= Convert.ToUInt16((((UInt16)file_buffer[chk_start_addr + 1] << 8) + (UInt16)file_buffer[chk_start_addr]));
chk_start_addr += 2;
seed_a += 0xDAAC;
seed_b ^= Convert.ToUInt16((((UInt16)file_buffer[chk_start_addr + 1] << 8) + (UInt16)file_buffer[chk_start_addr]));
chk_start_addr += 2;
if ((seed_a & 0xF) > 0)
{
var_1 = Convert.ToUInt16((seed_b << (16 - (seed_a & 0xF))) & 0xffff);
seed_b >>= (seed_a & 0xF);
seed_b |= var_1;
}
}
while (chk_start_addr != chk_end_addr);
seed_a -= 0x8631;
seed_a += 0xDAAC;
seed_b ^= 0xDF9B;
return (((UInt32)seed_b << 16) + seed_a);
}
public ChecksumResult tdi41_2002_checksum_search(byte[] file_buffer, UInt32 file_size, bool debug)
{
UInt32 seed_1, seed_2;
UInt16 seed_1_msb, seed_1_lsb, seed_2_lsb, seed_2_msb;
UInt32 chk_oldvalue, chk_value, chk_start_addr, chk_end_addr, chk_store_addr;
chk_found = 2;
chk_fixed = 0;
chk_match = 0;
// Find seed 1
seed_1 = tdi41_2002_checksum_calculate(file_buffer, 0x14000, 0x4bffe, 0x8631, 0xefcd, 0, 0, true);
seed_1_msb = (UInt16)(seed_1 >> 16);
seed_1_lsb = (UInt16)seed_1;
// Find seed 2
seed_2 = tdi41_2002_checksum_calculate(file_buffer, 0, 0x7ffe, 0, 0, 0, 0, true);
seed_2_msb = (UInt16)(seed_2 >> 16);
seed_2_lsb = (UInt16)seed_2;
// checksum 1
chk_oldvalue = ((UInt32)file_buffer[0xffff] << 24)
+ ((UInt32)file_buffer[0xfffe] << 16)
+ ((UInt32)file_buffer[0xfffd] << 8)
+ (UInt32)file_buffer[0xfffc];
chk_value = tdi41_2002_checksum_calculate(file_buffer, 0x8000, 0xfffb, seed_2_lsb, seed_2_msb, 0x4531, 0x3550, false);
if (chk_oldvalue != chk_value)
{
file_buffer[0xfffc] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[0xfffd] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[0xfffe] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[0xffff] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
chk_fixed++;
}
else chk_match++;
// Checksum 2
chk_oldvalue = ((UInt32)file_buffer[0x13fff] << 24)
+ ((UInt32)file_buffer[0x13ffe] << 16)
+ ((UInt32)file_buffer[0x13ffd] << 8)
+ (UInt32)file_buffer[0x13ffc];
chk_value = tdi41_2002_checksum_calculate(file_buffer, 0x10000, 0x13ffb, 0, 0, 0x8631, 0xefcd, false);
if (chk_oldvalue != chk_value)
{
file_buffer[0x13ffc] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[0x13ffd] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[0x13ffe] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[0x13fff] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
chk_fixed++;
}
else chk_match++;
// Checksum blocks loop
chk_store_addr = 0x4fffb;
do
{
if ((file_buffer[chk_store_addr + 13] == 0x56) &&
(file_buffer[chk_store_addr + 14] == 0x34) &&
(file_buffer[chk_store_addr + 15] == 0x2e) &&
(file_buffer[chk_store_addr + 16] == 0x31))
{
// Checksum
chk_start_addr = chk_store_addr - 0x3ffb;
chk_end_addr = chk_store_addr;
chk_oldvalue = ((UInt32)file_buffer[chk_store_addr + 4] << 24)
+ ((UInt32)file_buffer[chk_store_addr + 3] << 16)
+ ((UInt32)file_buffer[chk_store_addr + 2] << 8)
+ (UInt32)file_buffer[chk_store_addr + 1];
chk_value = tdi41_2002_checksum_calculate(file_buffer, chk_start_addr, chk_end_addr, seed_1_lsb, seed_1_msb, seed_1_lsb, seed_1_msb, false);
if (chk_oldvalue != chk_value)
{
file_buffer[chk_store_addr + 1] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[chk_store_addr + 2] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[chk_store_addr + 3] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[chk_store_addr + 4] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
chk_fixed++;
}
else chk_match++;
//Console.WriteLine("2002 start " + chk_start_addr.ToString("X8") + " - " + chk_end_addr.ToString("X8") + " store " + chk_store_addr.ToString("X8") + " file " + chk_oldvalue.ToString("X8") + " calc " + chk_value.ToString("X8"));
// Checksum
chk_start_addr = chk_store_addr + 5;
chk_end_addr = chk_store_addr + 0xb80;
chk_oldvalue = ((UInt32)file_buffer[chk_store_addr + 2948] << 24)
+ ((UInt32)file_buffer[chk_store_addr + 2947] << 16)
+ ((UInt32)file_buffer[chk_store_addr + 2946] << 8)
+ (UInt32)file_buffer[chk_store_addr + 2945];
chk_value = tdi41_2002_checksum_calculate(file_buffer, chk_start_addr, chk_end_addr, seed_1_lsb, seed_1_msb, seed_1_lsb, seed_1_msb, false);
if (chk_oldvalue != chk_value)
{
file_buffer[chk_store_addr + 2945] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[chk_store_addr + 2946] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[chk_store_addr + 2947] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[chk_store_addr + 2948] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
chk_fixed++;
}
else chk_match++;
//Console.WriteLine("2002 start " + chk_start_addr.ToString("X8") + " - " + chk_end_addr.ToString("X8") + " store " + chk_store_addr.ToString("X8") + " file " + chk_oldvalue.ToString("X8") + " calc " + chk_value.ToString("X8"));
// Checksum
chk_start_addr = chk_store_addr + 0xb85;
chk_end_addr = chk_store_addr + 0xc000;
chk_oldvalue = ((UInt32)file_buffer[chk_store_addr + 49156] << 24)
+ ((UInt32)file_buffer[chk_store_addr + 49155] << 16)
+ ((UInt32)file_buffer[chk_store_addr + 49154] << 8)
+ (UInt32)file_buffer[chk_store_addr + 49153];
chk_value = tdi41_2002_checksum_calculate(file_buffer, chk_start_addr, chk_end_addr, seed_1_lsb, seed_1_msb, seed_1_lsb, seed_1_msb, false);
if (chk_oldvalue != chk_value)
{
file_buffer[chk_store_addr + 49153] = Convert.ToByte(chk_value & 0x000000ff);
file_buffer[chk_store_addr + 49154] = Convert.ToByte((chk_value >> 8) & 0x000000ff);
file_buffer[chk_store_addr + 49155] = Convert.ToByte((chk_value >> 16) & 0x000000ff);
file_buffer[chk_store_addr + 49156] = Convert.ToByte((chk_value >> 24) & 0x000000ff);
chk_fixed++;
}
else chk_match++;
//Console.WriteLine("2002 start " + chk_start_addr.ToString("X8") + " - " + chk_end_addr.ToString("X8") + " store " + chk_store_addr.ToString("X8") + " file " + chk_oldvalue.ToString("X8") + " calc " + chk_value.ToString("X8"));
chk_found += 3;
}
chk_store_addr += 0x10000;
} while (chk_store_addr + 5 < file_size);
Console.WriteLine("tdi41v2002_chkfixed: " + chk_fixed.ToString() + " / " + chk_found.ToString());
Console.WriteLine("tdi41v2002_chkmatch: " + chk_match.ToString() + " / " + chk_found.ToString());
if (chk_fixed == 0) return ChecksumResult.ChecksumOK;
else if (chk_match > 3) return ChecksumResult.ChecksumFail;
else if (chk_fixed >= chk_found-1) return ChecksumResult.ChecksumTypeError;
return ChecksumResult.ChecksumFail;
}
UInt32 tdi41_2002_checksum_calculate(byte[] file_buffer, UInt32 chk_start_addr, UInt32 chk_end_addr, UInt16 seed_a, UInt16 seed_b, UInt16 seed_c, UInt16 seed_d, bool first_pass)
{
UInt32 count = chk_start_addr / 2;
UInt32 end_count = chk_end_addr / 2;
UInt32 buffer_addr = chk_start_addr;
UInt32 checksum, var_6, var_7 = 0;
UInt16 var_1 = 0, var_2 = 0, var_3, var_4, var_5;
if (count != end_count)
{
var_1 = seed_a;
var_2 = seed_b;
if (chk_start_addr == 0x8000)
{
var_1 = Convert.ToUInt16(var_1 ^ 0xD565);
var_2 += 0x308a;
}
do
{
var_1 ^= Convert.ToUInt16(((UInt16)file_buffer[buffer_addr + 1] << 8) + (UInt16)file_buffer[buffer_addr]);
var_3 = Convert.ToUInt16(var_2 & 0xf);
++count;
buffer_addr += 2;
var_4 = 0;
if ((var_2 & 0xf) > 0)
{
do
{
var_4 = (UInt16)(var_1 >> 15);
var_1 = (UInt16)(((var_1 * 2) + var_4));
--var_3;
} while (var_3 > 0);
}
var_2 -= (UInt16)((var_4 + ((UInt16)file_buffer[buffer_addr + 1] << 8) + (UInt16)file_buffer[buffer_addr]));
var_2 = (UInt16)(var_1 ^ var_2);
buffer_addr += 2;
++count;
if (count > end_count)
break;
var_5 = (UInt16)(((UInt16)file_buffer[buffer_addr + 1] << 8) + (UInt16)file_buffer[buffer_addr]);
buffer_addr += 4;
var_1 += (UInt16)((0xffff - var_5 + 0xdaad));
var_6 = (UInt32)((UInt16)file_buffer[buffer_addr - 1] << 8);
var_2 ^= (UInt16)((UInt16)var_6 + (UInt16)file_buffer[buffer_addr - 2]);
var_4 = (UInt16)(var_1 & 0xf);
count += 2;
if ((var_1 & 0xf) > 0)
{
do
{
var_6 = (var_6 | 0xffff) & var_2;
var_6 <<= 15;
var_2 = (UInt16)(((var_2 >> 1) + var_6));
--var_4;
} while (var_4 > 0);
}
} while (count <= end_count);
}
if (chk_start_addr == 0)
{
var_1 -= 0x79cf;
var_2 -= 0x1033;
}
if (!first_pass)
{
var_5 = seed_d;
var_1 -= seed_c;
var_6 = (UInt16)((seed_c | 0xffff) & 0xdaad);
var_1 += (UInt16)(var_6 - 1);
var_7 = var_7 & 0xffff;
for (count = (UInt32)(seed_c & 0xf); count > 0; var_5 = (UInt16)((((UInt32)var_5 >> 15) + var_7)))
{
--count;
var_7 = (var_7 | 0xffff) & var_5;
var_7 *= 2;
}
checksum = (UInt32)(((UInt32)var_1 + (((UInt32)var_5 ^ (UInt32)var_2) << 16)));
}
else
{
checksum = (UInt32)(((UInt32)var_1 + ((UInt32)var_2 << 16)));
}
return (checksum);
}
}
}