public static RSAParameters DecryptRsaKey(byte[] encryptedKey, byte[] kek)
{
var counter = new byte[0x10];
Array.Copy(encryptedKey, counter, 0x10);
var body = new byte[0x230];
Array.Copy(encryptedKey, 0x10, body, 0, 0x230);
var dec = new byte[0x230];
using (var storageDec = new Aes128CtrStorage(new MemoryStorage(body), kek, counter, false))
{
storageDec.Read(dec, 0);
}
var d = new byte[0x100];
var n = new byte[0x100];
var e = new byte[4];
Array.Copy(dec, 0, d, 0, 0x100);
Array.Copy(dec, 0x100, n, 0, 0x100);
Array.Copy(dec, 0x200, e, 0, 4);
BigInteger dInt = GetBigInteger(d);
BigInteger nInt = GetBigInteger(n);
BigInteger eInt = GetBigInteger(e);
RSAParameters rsaParams = RecoverRsaParameters(nInt, eInt, dInt);
TestRsaKey(rsaParams);
return(rsaParams);
}
private void DecryptKeyblobs(IProgressReport logger = null)
{
var cmac = new byte[0x10];
var expectedCmac = new byte[0x10];
var counter = new byte[0x10];
for (int i = 0; i < UsedKeyblobCount; i++)
{
if (KeyblobKeys[i].IsEmpty() || KeyblobMacKeys[i].IsEmpty() || EncryptedKeyblobs[i].IsEmpty())
{
continue;
}
Array.Copy(EncryptedKeyblobs[i], expectedCmac, 0x10);
Crypto.CalculateAesCmac(KeyblobMacKeys[i], EncryptedKeyblobs[i], 0x10, cmac, 0, 0xa0);
if (!Util.ArraysEqual(cmac, expectedCmac))
{
logger?.LogMessage($"Warning: Keyblob MAC {i:x2} is invalid. Are SBK/TSEC key correct?");
}
Array.Copy(EncryptedKeyblobs[i], 0x10, counter, 0, 0x10);
using (var keyblobDec = new Aes128CtrStorage(
new MemoryStorage(EncryptedKeyblobs[i], 0x20, Keyblobs[i].Length), KeyblobKeys[i], counter, false))
{
keyblobDec.Read(Keyblobs[i], 0);
}
}
}
private int FindKeyGeneration(Keyset keyset, IStorage storage)
{
var counter = new byte[0x10];
var decBuffer = new byte[0x10];
storage.Read(0x100, counter).ThrowIfFailure();
for (int i = 0; i < 0x20; i++)
{
var dec = new Aes128CtrStorage(storage.Slice(0x100), keyset.Package2Keys[i], counter, false);
dec.Read(0x50, decBuffer).ThrowIfFailure();
if (BitConverter.ToUInt32(decBuffer, 0) == Pk21Magic)
{
return(i);
}
}
throw new InvalidDataException("Failed to decrypt package2! Is the correct key present?");
}
public Package1(KeySet keySet, IStorage storage)
{
Storage = storage;
var reader = new BinaryReader(storage.AsStream());
BuildHash = reader.ReadBytes(0x10);
BuildDate = reader.ReadAscii(0xE);
Field1E = reader.ReadUInt16();
reader.BaseStream.Position = 0x3FE0;
Pk11Size = reader.ReadInt32();
reader.BaseStream.Position += 0xC;
Counter = reader.ReadBytes(0x10);
// Try decrypting the PK11 blob with all known package1 keys
IStorage encStorage = Storage.Slice(0x4000, Pk11Size);
byte[] decBuffer = new byte[0x10];
for (int i = 0; i < 0x20; i++)
{
var dec = new Aes128CtrStorage(encStorage, keySet.Package1Keys[i].DataRo.ToArray(), Counter, true);
dec.Read(0, decBuffer).ThrowIfFailure();
if (BitConverter.ToUInt32(decBuffer, 0) == Pk11Magic)
{
KeyRevision = i;
Pk11 = new Pk11(new CachedStorage(dec, 4, true));
return;
}
}
throw new InvalidDataException("Failed to decrypt PK11! Is the correct key present?");
}
