/*
* Outputs the specific XOR key for the given version.
*
* @param version The pack file version
* @param key The outputted key block
*
*/
public static void GetXorKey(PackVersion version, out byte[] key)
{
switch (version)
{
case PackVersion.MS2F:
key = MS2F_XOR.Value;
break;
case PackVersion.NS2F:
key = NS2F_XOR.Value;
break;
case PackVersion.OS2F:
key = OS2F_XOR.Value;
break;
case PackVersion.PS2F:
key = PS2F_XOR.Value;
break;
default:
{
// Nexon always defaults to MS2F here.
key = MS2F_XOR.Value;
break;
}
}
}
public PackFileHeaderVer3(PackVersion version, BinaryReader reader) : this(version) {
this.BufferFlag = (Encryption)reader.ReadUInt32(); //[ecx+8]
this.FileIndex = reader.ReadInt32(); //[ecx+12]
this.EncodedFileSize = reader.ReadUInt32(); //[ecx+16]
this.reserved[0] = reader.ReadInt32(); //[ecx+20]
this.CompressedFileSize = reader.ReadUInt64(); //[ecx+24] | [ecx+28]
this.FileSize = reader.ReadUInt64(); //[ecx+32] | [ecx+36]
this.Offset = reader.ReadUInt64(); //[ecx+40] | [ecx+44]
}
public static PackStreamVer3 ParseHeader(BinaryReader reader, PackVersion version)
{
return(new PackStreamVer3(version)
{
FileListCount = reader.ReadUInt32(),
reserved = reader.ReadUInt32(),
CompressedDataSize = reader.ReadUInt64(),
EncodedDataSize = reader.ReadUInt64(),
CompressedHeaderSize = reader.ReadUInt64(),
EncodedHeaderSize = reader.ReadUInt64(),
DataSize = reader.ReadUInt64(),
HeaderSize = reader.ReadUInt64()
});
}
public static PackFileHeaderVer3 CreateHeader(PackVersion version, int index, Encryption flag, ulong offset, byte[] data)
{
CryptoManager.Encrypt(version, data, flag, out uint size, out uint compressedSize, out uint encodedSize);
return(new PackFileHeaderVer3(version)
{
BufferFlag = flag,
FileIndex = index,
EncodedFileSize = encodedSize,
CompressedFileSize = compressedSize,
FileSize = size,
Offset = offset
});
}
/*
* Outputs the Key and IV blocks for the specified version.
*
* @param version The pack file version
* @param uKeyOffset The key index to output (this is compressedSize)
* @param userKey The outputted Key block
* @param ivChain The outputted IV (CTR) block
*
*/
public static void GetKeyAndIV(PackVersion version, uint keyOffset, out byte[] userKey, out byte[] ivChain)
{
IMultiArray key;
IMultiArray iv;
switch (version)
{
case PackVersion.MS2F:
key = MS2F_KEY;
iv = MS2F_IV;
break;
case PackVersion.NS2F:
key = NS2F_KEY;
iv = NS2F_IV;
break;
case PackVersion.OS2F:
key = OS2F_KEY;
iv = OS2F_IV;
break;
case PackVersion.PS2F:
key = PS2F_KEY;
iv = PS2F_IV;
break;
default:
{
throw new Exception("ERROR generating Key/IV: the specified package version does not exist!");
}
}
userKey = new byte[KEY_LEN];
ivChain = new byte[IV_LEN];
for (int i = 0; i < KEY_LEN; i++)
{
userKey[i] = key[(keyOffset & 0x7F)][i];
if (i < IV_LEN)
{
ivChain[i] = iv[(keyOffset & 0x7F)][i];
}
}
}
private static byte[] EncryptXor(PackVersion version, byte[] src, uint size, uint sizeCompressed)
{
CipherKeys.GetXorKey(version, out byte[] key);
uint uBlock = size >> 2;
uint uBlockOffset = 0;
int nKeyOffset = 0;
if (uBlock != 0)
{
while (uBlockOffset < uBlock)
{
uint pBlockData = BitConverter.ToUInt32(src, (int)(4 * uBlockOffset)) ^
BitConverter.ToUInt32(key, 4 * nKeyOffset);
Buffer.BlockCopy(BitConverter.GetBytes(pBlockData), 0, src, (int)(4 * uBlockOffset),
sizeof(uint));
nKeyOffset = ((ushort)nKeyOffset + 1) & 0x1FF;
uBlockOffset++;
}
}
uBlock = (size & 3);
if (uBlock != 0)
{
int nStart = (int)(4 * uBlockOffset);
uBlockOffset = 0;
nKeyOffset = 0;
while (uBlockOffset < uBlock)
{
src[nStart + uBlockOffset++] ^= (byte)(key[nKeyOffset]);
nKeyOffset = ((ushort)nKeyOffset + 1) & 0x7FF;
}
}
return(src);
}
// Decryption Routine: Base64 -> AES -> Zlib
private static byte[] Decrypt(PackVersion version, uint size, uint sizeCompressed, Encryption flag, byte[] src)
{
if (flag.HasFlag(Encryption.Aes))
{
// Get the AES Key/IV for transformation
CipherKeys.GetKeyAndIV(version, sizeCompressed, out byte[] key, out byte[] iv);
// Decode the base64 encoded string
src = Convert.FromBase64String(Encoding.UTF8.GetString(src));
// Decrypt the AES encrypted block
AESCipher pCipher = new AESCipher(key, iv);
pCipher.TransformBlock(src, 0, size, src, 0);
}
else if (flag.HasFlag(Encryption.Xor))
{
// Decrypt the XOR encrypted block
src = EncryptXor(version, src, size, sizeCompressed);
}
return(flag.HasFlag(Encryption.Zlib) ? ZlibStream.UncompressBuffer(src) : src);
}
// Encryption Routine: Zlib -> AES -> Base64
public static byte[] Encrypt(PackVersion version, byte[] src, Encryption flag, out uint size,
out uint sizeCompressed, out uint sizeEncoded)
{
byte[] pEncrypted;
if (flag.HasFlag(Encryption.Zlib))
{
pEncrypted = ZlibStream.CompressBuffer(src);
}
else
{
pEncrypted = new byte[src.Length];
Buffer.BlockCopy(src, 0, pEncrypted, 0, src.Length);
}
size = (uint)src.Length;
sizeCompressed = (uint)pEncrypted.Length;
if (flag.HasFlag(Encryption.Aes))
{
// Get the AES Key/IV for transformation
CipherKeys.GetKeyAndIV(version, sizeCompressed, out byte[] key, out byte[] iv);
// Perform AES block encryption
var pCipher = new AESCipher(key, iv);
pCipher.TransformBlock(pEncrypted, 0, size, pEncrypted, 0);
// Encode the encrypted data into a base64 encoded string
pEncrypted = Encoding.UTF8.GetBytes(Convert.ToBase64String(pEncrypted));
}
else if (flag.HasFlag(Encryption.Xor))
{
// Perform XOR block encryption
pEncrypted = EncryptXor(version, pEncrypted, size, sizeCompressed);
}
sizeEncoded = (uint)pEncrypted.Length;
return(pEncrypted);
}
private PackFileHeaderVer3(PackVersion version)
{
this.Version = version;
this.reserved = new int[1];
}
private PackStreamVer3(PackVersion version)
{
this.Version = version;
this.FileList = new List <PackFileEntry>();
}
private PackFileHeaderVer3(PackVersion version)
{
Version = version;
Reserved = new int[1];
}