public void Open(string UpdateDat_Path)
{
IsValid = false;
FileStream fsin = null;
try
{
fsin = File.OpenRead(UpdateDat_Path);
}
catch
{
if (fsin != null)
{
fsin.Close();
}
throw new Exception("Error opening file " + UpdateDat_Path);
}
if (fsin.Length != UPDATE_DAT_SIZE)
{
fsin.Close();
throw new Exception(UpdateDat_Path + "\nFile size error!");
}
byte[] inbuffer = new byte[fsin.Length + 1];
fsin.Read(inbuffer, 0, (int)fsin.Length);
fsin.Close();
m_eraseA = inbuffer[9];
m_eraseCS = inbuffer[17];
Version = inbuffer[0];
//Decrypt firmwares (stage 1)
m_firmwareA = new byte[ENCRYPTED_FIRMWARE_SIZE];
m_firmwareCS = new byte[ENCRYPTED_FIRMWARE_SIZE];
for (uint i = 0; i < ENCRYPTED_FIRMWARE_SIZE; i++)
{
m_firmwareA[i] = (byte)(inbuffer[0xA1C + i] ^
inbuffer[
0x118 +
((BitConverter.ToInt32(inbuffer, 0x14) + i) & 0x3FF)] ^
inbuffer[0x18 + ((i / 80) & 0xFF)]);
m_firmwareCS[i] = (byte)(inbuffer[0x2671C + i] ^
inbuffer[
0x61C +
((BitConverter.ToInt32(inbuffer, 0x518) + i) & 0x3FF)] ^
inbuffer[0x51C + ((i / 80) & 0xFF)]);
}
//Check if decryption was O.K.
CRC32 crc32 = new CRC32();
uint crca = ~crc32.GetCRC32(m_firmwareA, 0xFFFFFFFF);
uint crccs = ~crc32.GetCRC32(m_firmwareCS, 0xFFFFFFFF);
if (crca != BitConverter.ToUInt32(inbuffer, 4) || crccs != BitConverter.ToUInt32(inbuffer, 12))
{
throw new Exception(UpdateDat_Path + "\nData CRC error!");
}
//Check if decrypted firmware signatures are O.K.
if (BitConverter.ToUInt32(GetUnencryptedFirmware((int)FIRMWARE_TYPE.FIRMWARE_A),
FIRMWARE_SIGNATURE_OFFSET) != FIRMWARE_SIGNATURE ||
BitConverter.ToUInt32(GetUnencryptedFirmware((int)FIRMWARE_TYPE.FIRMWARE_CS),
FIRMWARE_SIGNATURE_OFFSET) != FIRMWARE_SIGNATURE)
{
throw new Exception("Firmware decryption error!");
}
IsValid = true;
}